Nanofibers with genotyped Bacillus strains exhibiting antibacterial and immunomodulatory activity

Biofilm-associated diseases such as periodontitis are widespread and challenging to treat which calls for new strategies for their effective management. Probiotics represent a promising approach for targeted treatment of dysbiosis in biofilm and modulation of host immune response. In this interdisciplinary study, nanofibers with two autochthonous Bacillus strains 27.3.Z and 25.2.M were developed. The strains were isolated from the oral microbiota of healthy individuals, and their genomes were sequenced and screened for genes associated with antimicrobial and immunomodulatory activities, virulence factors, and transferability of resistance to antibiotics. Spores of two Bacillus strains were incorporated individually or in combination into hydrophilic poly(ethylene oxide) (PEO) and composite PEO/alginate nanofibers. The nanofiber mats were characterised by a high loading of viable spores (> 7 log CFU/mg) and they maintained viability during electrospinning and 6 months of storage at room temperature. Spores were rapidly released from PEO nanofibers, while presence of alginate in the nanofibers prolonged their release. All formulations exhibited swelling, followed by transformation of the nanofiber mat into a hydrogel and polymer erosion mediating spore release kinetics. The investigated Bacillus strains released metabolites, which were not cytotoxic to peripheral blood mononuclear cells (PBMCs) in vitro. Moreover, their metabolites exhibited antibacterial activity against two periodontopathogens, an antiproliferative effect on PBMCs, and inhibition of PBMC expression of proinflammatory cytokines. In summary, the developed nanofiber-based delivery system represents a promising therapeutic approach to combat biofilm-associated disease on two fronts, namely via modulation of the local microbiota with probiotic bacteria and host immune response with their metabolites.

Statistical analysis of shoreline change reveals erosion and baseline are increasing off the northern Tamil Nadu Coasts of India

Many tourists have been recently attracted towards the coasts around the world, especially to the large urban centres and economically significant areas. In the last four decades, there is a significant increase in the key coastal developments and tourist's attractions like major ports, minor ports, fishing harbours, desalination plants, shore protection structures, and many more along the southeast coasts of India, in particular, northern Tami Nadu coastal stretches. The shoreline change study of these regions were carried out using the geospatial technologies (satellite remote sensing and geographical information system) to examine potential modifications occurred during the last 32 years between March 1990 and May 2022. This study used Landsat satellite images of spatial resolution 30 m to track the shoreline changes which was extracted using the Digital Image Processing software and techniques. In addition, the United States Geological Survey (USGS) developed Digital Shoreline Analysis System (DSAS) v5.2 software, an add-on tool to ArcGIS used for the statistical analysis to compute the shoreline rate of change. The linear regression rate (LRR) and end point rate (EPR) statistics were used to identify the eroding, accreting, and stable shoreline between Kattupalli coast and Kalpakkam coast of the northern Tamil Nadu coasts. This shoreline study of 106 km was carried out by dividing it into six zones (zone 1 to zone 6), and the DSAS analysis conveys that the shoreline of zone 1 (Kattupalli) and zone 2 (Ennore) shows erosion compared to other four zones. In locations where the coast is vulnerable, national mitigation measures must be implemented.

Remineralization effect of three different agents on initial caries and erosive lesions: a micro-computed tomography and scanning electron microscopy analysis

BACKGROUND

This study aimed to investigate the remineralization efficiency of Sensodyne Promine containing Sodium flouride (NaF), GC Tooth Mousse containing CPP-ACP, and Agarta herbal toothpaste on initial caries and erosion using micro-computed tomography (CT) and scanning electron microscopy (SEM).

METHODS

Forty-five third-molar teeth for micro-CT were divided into three main groups after initial scans (T₁) were completed. Artificial caries lesions were created with the demineralization cycle (group 1, n = 15) and artificial erosion lesions were created with orange juice (group 2, n = 15) and Cola (group 3, n = 15), and second scans (T₂) were performed. The groups were divided into three subgroups within themselves. Sensodyne Promine toothpaste (subgroup 1a, 2a, 3a), GC Tooth Mousse topical cream (subgroup 1b, 2b, 3b), and Agarta herbal toothpaste (subgroup 1c, 2c, 3c) were applied using soft-tipped brushes for 2 min, twice per day for 15 days, and then a third scan (T₃) was performed. Mineral density, surface area, and lesion volume and depth were calculated using micro-CT. Changes in the surface morphology of the teeth were examined using SEM in 13 samples representing each group, subgroup, and healthy enamel. In the analysis of the data obtained from the scans performed at three different times (T₁, T₂, T₃), one-way analysis of variance (ANOVA) with the post-hoc Tukey test, repeated measures ANOVA with the post-hoc Bonferroni test, and paired sample t-test analyses were used.

RESULTS

All three agents caused a statistically significant increase in mineral density, and a decrease in surface area and lesion volume and depth (p < 0.05). There was no statistically significant difference between the groups in remineralization efficiency (p > 0.05). A statistically significant difference was found between the groups regarding the mineral density of the tissue that increased after remineralization (NaF > CPP-ACP > He; p < 0.05).

CONCLUSION

The remineralization efficacy of herbal toothpaste as an alternative to NaF and CPP-ACP was found to be successful.

Improved Surface Layer Erosion of Pit and Fissure Caries Lesions in Preparation for Resin Infiltration

The penetration of a low-viscosity resin (infiltrant) into caries lesions depends on the erosion of the relatively impermeable surface layer (SL) that covers the lesion body. The present study aimed to evaluate the effect of different abrasive pretreatments on erosion of the SL and on penetration of an infiltrant into occlusal caries lesions, simultaneously. Sixty extracted human molars showing International Caries Detection and Assessment System (ICDAS-2) lesions were randomly allocated to 5 groups. A small area of each lesion was covered with resin before etching. Twelve lesions each were etched with either 15% HCl-gel (H120) or 37% H3PO4-gel (P120) for 120 s. Furthermore, the standard 15% HCl-gel or either one of two experimental etchants (HCl-gel or H3PO4-gel, each including abrasives) were applied for either 120 s or 30 s using a brush (surface pressure 150 g) (H30B, P120BA, H30BA). After rinsing and drying, all lesions were infiltrated for 180 s (Icon; DMG). From each tooth sections were prepared and visualized using confocal microscopy. SL of unetched areas and the lesion depth were 33 (23/51) μm and 537 (274/876) μm, respectively, both not differing significantly between groups. H120, H30B, and H30BA showed significantly higher SL reduction compared with P120 or P120BA, but only for H30BA SL was eroded almost completely (p < 0.05; Mann-Whitney test). Compared to other groups, occlusal lesions were significantly more infiltrated in H30BA (p < 0.05; Mann-Whitney test). HCl-gel including abrasives that was rubbed onto the enamel surface with a brush seems to be most effective to erode SLs of caries lesion situated in fissures and enable an almost complete subsequent resin infiltration.

Effects of gastric acid and mechanical toothbrushing in CAD-CAM restorative materials: Mechanical properties, surface topography, and biofilm adhesion

OBJECTIVE

To evaluate the effects of simulated gastric acid erosion combined with mechanical toothbrushing abrasion on the mechanical properties, surface topography, and biofilm adhesion of different CAD/CAM materials.

MATERIAL AND METHODS

Specimens of zirconia-reinforced lithium silicate glass-ceramic (ZLS), polymer-infiltrated ceramic network (PICN), feldspathic glass-ceramic (FE), and two nanoceramic resins (RK, RG), were submitted to the following challenges: erosion (E), abrasion (A), erosion combined with abrasion (E + A), or remained untreated (control - C). After challenges, flexural strength was evaluated, while microhardness (KHN) and surface roughness (Ra) were tested before and after treatments. The biofilm adhesion (Streptococcus mutans ATCC 700610, Streptococcus sanguinis ATCC 10556 e Candida albicans MYA 2876) was determined by the counting of colonies forming units per milliliters (UFC/mL) after erosive and abrasive challenges.

RESULTS

FE showed the lowest flexural strengths, while ZLS and RG exhibited the highest, while PICN and RK, had intermediate values. PICN, ZLS, and FE showed lower microhardness after E and E + A challenges than polymer-based materials (RG and RK). FE surface roughness increased after E and E + A challenges and after A and E + A challenges for RK. Biofilm formation after erosive/abrasive challenges was higher on ZLS than FE, RK, and RG, but no different than PICN. RK and RG exhibited the lowest biofilm formation among the groups. Furthermore, E + A challenges held significant changes in the surface of the materials, which were more severe on the surface of glass ceramics and hybrid materials.

CONCLUSION

Erosive challenges combined with abrasion negatively influenced the mechanical properties and surface topography of most CAD/CAM materials and increased the biofilm adhesion on ZLS. Besides, the severity of the damage is related to the type and composition of each material.

Ultrastructure of the Dentin Pellicle and the Impact of Erosion

While the ultrastructure of the enamel pellicle and its erosion protective properties are well studied, the dentin pellicle is still neglected in dental research. Therefore, the ultrastructure and erosion protective properties of a pellicle formed on bovine dentin specimens were investigated in the present study. The dentin pellicle was formed in situ for 3, 30, 120, and 360 min at buccal or palatal oral sites of 3 subjects and analyzed by transmission electron microscopy. In order to clarify the impact of an erosive challenge to the ultrastructure of the pellicle and the underlying dentin, specimens were exposed to the oral cavity and eroded in vivo with 0.1% or 1% citric acid either immediately or after 30 min of pellicle formation. Specimens that were eroded without exposure to the oral cavity served as control. In another trial, specimens with a 30-min pellicle were exposed to the oral cavity for a further 60 min after the erosive challenge to investigate the effect of saliva on the impaired pellicle and dentin. Transmission electron micrographs reveal a globular and granular structured pellicle layer, which was thicker when the pellicle was formed buccally or with longer formation times. Erosion with citric acid reduced the thickness of the pellicle and interrupted its continuity. The dentin was also affected by erosion, which was represented by a lower electron density and formation of demineralized lacunae. These were infiltrated by a granular structured material when specimens were exposed to the oral cavity. After further intraoral exposure, the infiltration was more pronounced, indicating a significant impact of saliva on the demineralized dentin. A reformation of the dentin pellicle on the other hand did not occur. In conclusion, the dentin pellicle is neither acid-resistant nor able to effectively protect dentin from erosion.

Hydrodynamic and geochemical controls on soil carbon mineralization upon entry into aquatic systems

Erosion is the most widespread form of soil degradation and an important pathway of carbon transfer from land into aquatic systems, with significant impact on water quality and carbon cycle. However, it remains debatable whether erosion induces a carbon source or sink, and the fate of eroded soil carbon in aquatic systems remains poorly constrained. Here, we collect 41 representative soils from seven erosion-influenced basins and conduct microcosm simulation experiments to examine the fate of soil carbon under three different scenarios. We showed that soil carbon mineralization was generally promoted (by up to 10 times) in water under turbulence relative to in soils, but suppressed under static conditions upon entering into aquatic systems. Moreover, the enhancement of mineralization in turbulent systems is primarily related to soil aggregate content, while suppression in static systems positively relates to macromolecule abundance, indicating that soil geochemistry affects the magnitude of hydrodynamic effects on carbon mineralization. Random forest model further predicts that erosion may induce significant carbon sources in basins dominated by turbulent waters and aggregate-rich soils. Our findings demonstrate hydrodynamic and geochemical controls on soil carbon mineralization upon delivery into aquatic systems, which is a non-negligible part of the boundless carbon cycle and must be considered when making region-specific conservation strategies to reduce CO₂ emissions from inland waters.

Influence of cover crops at the four spheres: A review of ecosystem services, potential barriers, and future directions for North America

Cover crops have been studied for over a century, but the recognition of a complex interaction of cover crop on the Earth's biosphere, lithosphere, hydrosphere, and atmosphere is relatively recent. Furthermore, previously published cover crop research has largely focused on evaluating cover crop impacts on subsequent crop yield. Understanding the cover crop-induced benefits on soil organic carbon (SOC) sequestration, nitrous oxide (N₂O) emissions, wind and water erosion, weed control, and soil microbial communities has gained considerable attention in the last few decades, which is crucial to make progress towards developing sustainable agricultural production systems. New research is continuously published to gain a comprehensive understanding of the multiple ecosystem services provided by cover crops. Here, in this review, we aimed to (a) summarize current knowledge related to cover crop impacts on agroecosystem functioning and explore the potential mechanisms responsible for those effects, and (b) identify the key factors limiting the adoption of cover crops into agroecosystems and the conspicuous knowledge gaps in cover crop research. Overall, the review results suggest that cover crops increased subsequent crop yield, increased SOC storage, increased weed suppression, mitigated N₂O emissions, reduced wind and water erosion, suppressed plant pathogens, and increased soil microbial activity and wildlife biodiversity. However, the magnitude of benefits observed with cover crops varied with cover crop type, location, and the duration of cover cropping. Notably, cover crop termination methods, designing crop rotations to fit cover crops, additional costs associated with cover crop integration, and uncertainty related to economic returns with cover crops are some of the major barriers limiting the adoption of cover crops into production systems, particularly in North America. In addition to long-term effects, future research on cover crop agronomy, breeding cover crop cultivars, and interactive effects of cover crops with other sustainable land management practices is needed.

New bone formation after arthroscopic Bankart repair for unstable shoulders with an erosion-type glenoid defect

BACKGROUND

The purpose of the present study was to retrospectively evaluate new bone formation after arthroscopic Bankart repair (ABR) and the influence of new bone formation on recurrence in shoulders with an erosion-type glenoid defect.

METHODS

We analyzed data on shoulders with an erosion-type glenoid defect. Participants were patients who underwent computed tomography to evaluate new bone formation after ABR performed from 2004 to 2021 and were followed for a minimum of 2 years. We investigated the factors influencing new bone formation, in particular the presence of an intraoperative bone fragment, and the influence of new bone formation and its size on postoperative recurrence.

RESULTS

A total of 100 shoulders were included. The mean glenoid defect size was 10.1% ± 6.3% (range, 1.2%-31.5%). New bone formed postoperatively in 15 shoulders (15.0%) and was seen in significantly more shoulders with an intraoperative bone fragment (11 of 18, 61.1%) than in those without a fragment (4 of 82, 4.9%; P < .001). Recurrence occurred in 22 shoulders (22.0%), and the rate of recurrence was not different between shoulders with new bone formation (3 of 15, 20.0%) and without new bone formation (19 of 85, 22.4%; P = .999). Among the 15 shoulders with new bone formation, the size of the new bone fragments relative to glenoid width was <5% in 2 shoulders, 5%-<7.5% in 8 shoulders, 7.5%-<10% in 3 shoulders, and ≥10% in 2 shoulders; in all 3 shoulders with postoperative recurrence, the relative size was <7.5%.

CONCLUSIONS

Even in shoulders with an erosion-type glenoid defect, new bone may form after ABR, especially in shoulders with an intraoperative bone fragment. However, new bone formation does not decrease the rate of postoperative recurrence.

In situ measurement of cavitation damage from single bubble collapse using high-speed chronoamperometry

We quantitatively study cavitation damage non-invasively, in-place and time-resolved at microsecond resolution. A single, laser-induced bubble is generated in an aqueous NaCl solution close to the surface of an aluminum sample. High-speed chronoamperometry is used to record the corrosion current flowing between the sample and an identical aluminum electrode immersed in the same solution. This configuration makes it possible to measure the cavitation damage in the nanometer thin passive layer of the aluminum surface via the corrosion current from the repassivation. Synchronously with the corrosion current, the bubble dynamics is recorded via high-speed imaging. Correlation between the two measurements allows contributing cavitation damage to the respective stages of the bubble dynamics. The largest cavitation-induced currents were observed for the smallest initial bubble-to-surface stand-off distances. As the bubble re-expands and collapses again in several stages, further current peaks were detected implying a sequence of smaller damage. At intermediate stand-offs the bubble was not damaging and at large stand-off distances, the bubble was only damaging during the second collapse which again occurs at the solid surface.

A Brief History of Tooth Wear

Historical publications that have significantly improved the understanding of tooth wear mechanisms are reviewed with a focus on descriptions of the lesions, the evolution of their classification systems, and considerations addressing the main risk factors. Surprisingly, most important advances are often the oldest. Likewise, they are currently only marginally known, which requires a major dissemination effort.

Deep Content Information Retrieval for COVID-19 Detection from Chromatic CT Scans

In this paper, we investigate the role of the chromatic information in CT scans in COVID-19 detection and we aim to confirm the inclusion of the artificial intelligence findings in assisting COVID-19 diagnosis. This paper proposes a freezing-based convolutional neural network learning using a morphological transformation of CT images to classify COVID-19 cohorts to help in prognostication pneumonia disease monitoring. The experiments made on the collected CT images from previous works have proven to be a powerful aid to recognize the lesions in CT images which works at comprehensively greater accuracy and speed. The proposed CNN architecture has reflected the viral proliferation in infected patients and archives an accuracy of 87.56% with an improvement by 3% compared to the baseline method on the available database of CT images.

Surface structure on abandoned upland blanket peatland tracks

Temporary permissions are often granted for track use on peatlands. However, even when peatland track designs attempt to minimise environmental impacts via use of mesh systems, such linear disturbances may have persistent impacts. We evaluated the surface peatland structure of five abandoned tracks (four with a mesh surface, one unsurfaced) with varying past usage frequencies, at an upland site in northern England. Simplification of the surface nanotopography was found on all tracks compared to surrounding control areas, with increased micro-erosion patterns in rutted areas, and invasive species on some treatments. The frequency of previous usage was not found to be a significant factor controlling nano-topographic loss. Edge effects and hillslope position were influential in places, but these effects were not consistent across treatments. Nano-topographic recovery was found to be inhibited when track usage commenced within a short time frame after track construction. Mesh tracks appear to create a spatial constraint leading to poor development of plants and a reduced ability to form characteristic structures which are integral to mire function.

Long term follow-up after minimally invasive sacrocolpopexy

INTRODUCTION AND HYPOTHESIS

Pelvic organ prolapse (POP) is a benign condition that can adversely affect women's quality of life. Minimally invasive mesh sacrocolpopexy is an effective surgical treatment for POP. This study aims to assess the perioperative, postoperative, and long term (10 years) outcome of a single institution cohort undergoing minimally invasive sacrocolpopexy.

METHODS

This retrospective study included all cases of laparoscopic sacrocolpopexy performed between 2003 and 2016. Patients were contacted by phone in 2022 for long term follow-up. Data on operative time, length of hospital stay, conversion rate, perioperative injuries, early and late postoperative complications and subjective success rates were collected.

RESULTS

Ninety-five patients were included aged 60±12 years. Most patients (72%) presented grade 3 POP. Grade of prolapse (3±0.4 vs 3±0.5, p<0.01) and hospital stay (3±1.1 vs 3.1±1.7; p<0.01) were significantly higher in patients who developed early postoperative complications (1^st year). At long term follow-up (12±3 years), 48 patients responded. Nine subjects (19%) presented a subjective recurrence with bulge symptoms. Surgery satisfaction was of 79%. The most frequent de novo reported symptom was urge urinary incontinence followed by stress urinary incontinence. Three cases (3%) of mesh erosion were described, all occurred after the 5th postoperative year.

CONCLUSIONS

Laparoscopic mesh sacrocolpopexy is a safe surgical technique that shows satisfying and consistent long-term results despite the occasional onset of new urinary symptoms.

Infection in patients with subcutaneous implantable cardioverter-defibrillator: Results of the S-ICD Post Approval Study

BACKGROUND

Early subcutaneous implantable cardioverter-defibrillator (S-ICD) studies included atypical cohorts of patients who were younger with fewer comorbidities. Recent S-ICD studies included patient populations with more comorbidities.

OBJECTIVES

The goals of this study were to determine the incidence and predictors of S-ICD-related infection over a 3-year follow-up period and to use these results to develop an infection risk score.

METHODS

The S-ICD Post Approval Study is a US prospective registry of 1637 patients. Baseline demographic characteristics and outcomes with 3-year postimplantation follow-up were compared between patients with and without device-related infection. A risk score was derived from multivariable proportional hazards analysis of 22 variables.

RESULTS

Infection was observed in 55 patients (3.3%), with 69% of infections occurring within 90 days and a vast majority (92.7%) within 1 year of implantation. Late infections more likely involved device erosion; no infections occurred after year 2. The annual mortality rate postinfection was 0.6%/y. No lead extraction complications or bacteremia related to infection were observed. An infection risk score was created with diabetes, age, prior transvenous ICD implant, and ejection fraction as predictors. Patients with a risk score of ≥3 had an 8.8 hazard ratio (95% confidence interval 2.8-16.3) of infection compared with a 0 risk score.

CONCLUSION

Infection rates in the S-ICD Post Approval Study were similar to other S-ICD populations and not associated with systemic blood-borne infections. Late infection (>1 year) is uncommon and associated with system erosion. A high-risk infection cohort can be identified that may facilitate preventive measures.

Suprapubic-assisted transurethral excision of eroded transvaginal cerclage suture

AIM OF THE VIDEO/INTRODUCTION

The aim was to demonstrate our minimally invasive technique for excision of eroded transvaginal cervical cerclage suture through the bladder mucosa using a suprapubic-assisted transurethral approach. Transvaginal cervical cerclage is a common treatment for cervical insufficiency in pregnancy. Complications such as erosion are rare, as the duration of treatment is typically several months, with cerclage placement in the second trimester and complete removal prior to the onset of labor. Retained suture can lead to erosion through the vaginal epithelium and into other organs, as seen in our case. Our technique offers a minimally invasive approach to the excision of eroded transvaginal cervical cerclage suture through the bladder mucosa.

METHODS

A narrated, stepwise video demonstration for removal of eroded cervical cerclage through bladder epithelium with suprapubic-assisted transurethral technique in a single patient was carried out. Key strategies for a successful outcome include: use of a Carter-Thomason device for suprapubic assistance in lieu of suprapubic trocar or suprapubic incision, use of rigid biopsy forceps for improved traction on the eroded suture, performing a methylene blue test for evaluation of vesicovaginal fistula after excision procedure.

RESULTS

At her 2-week postoperative evaluation, the patient reported resolution of all symptoms. The Carter-Thomason incision was well healed, and postoperative urinalysis was negative for hematuria.

CONCLUSIONS

A suprapubic-assisted transurethral approach can be used as a minimally invasive technique for excision of eroded transvaginal cervical cerclage suture through the bladder mucosa.

Artificial intelligence for diagnosing gastric lesions under white-light endoscopy

BACKGROUND

The ability of endoscopists to identify gastric lesions is uneven. Even experienced endoscopists may miss or misdiagnose lesions due to heavy workload or fatigue or subtle changes in lesions under white-light endoscopy (WLE). This study aimed to develop an artificial intelligence (AI) system that could diagnose six common gastric lesions under WLE and to explore its role in assisting endoscopists in diagnosis.

METHODS

Images of early gastric cancer, advanced gastric cancer, submucosal tumor, polyp, peptic ulcer, erosion, and lesion-free gastric mucosa were retrospectively collected to train and test the system. The performance of the system was compared with that of 12 endoscopists. The performance of endoscopists with or without referring to the system was also evaluated.

RESULTS

A total of 29,809 images from 8947 patients and 1579 images from 496 patients were used to train and test the system, respectively. For per-lesion analysis, the overall accuracy of the system was 85.7%, which was comparable to that of senior endoscopists (85.1%, P = 0.729) and significantly higher than that of junior endoscopists (78.8%, P < 0.001). With system assistance, the overall accuracies of senior and junior endoscopists increased to 89.3% (4.2%, P < 0.001) and 86.2% (7.4%, P < 0.001), respectively. Senior and junior endoscopists achieved varying degrees of improvement in the diagnostic performance of other types of lesions except for polyp. The diagnostic times of senior (3.8 vs 3.2 s per image, P = 0.500) and junior endoscopists (6.2 vs 4.6 s per image, P = 0.144) assisted by the system were both slightly shortened, despite no significant differences.

CONCLUSIONS

The proposed AI system could be applied as an auxiliary tool to reduce the workload of endoscopists and improve the diagnostic accuracy of gastric lesions.

Historical and projected changes in hydrological and sediment connectivity under climate change in a tropical catchment of Mexico

Hydrological and erosion dynamics are prone to change due to natural factors, human activities, or climate change. These changes are mainly related to modifications of land use and cover and can be assessed through the concept of connectivity, which analyzes how the spatial distribution of the elements facilitates runoff and sediment transport. The objective of this study was to evaluate changes in hydrological and sediment connectivity over 42 years and projected under a climate change scenario in the tropical Santa Cruz catchment in Aquismón, S.L.P., Mexico. The index of connectivity (IC) was computed using SedInConnect version 2.3 and the ArcSWAT model to estimate runoff. Hydrological connectivity and runoff were projected for 2027 using the MPI ECHAM 5 in the A2 climate change scenario. The results indicated that spatio-temporal changes in land use/cover, in conjunction with geomorphological features and expected climate change, would modify hydrological and sediment connectivity, especially in flat areas, where conversion of natural vegetation to cropland was steadily increasing over the years. Under future conditions, runoff and sediment transport are likely to increase, which will impact soil erosion and vulnerability to flooding but will not necessarily be negative. The study shows how spatial-temporal integration of runoff, sediments, landforms, land use cover and change, and connectivity can improve our understanding of catchment dynamics and the importance of analyses that characterize their evolution. The results can subsequently be applied and replicated in other catchments for management and restoration purposes.

Detailing the organic matter in suspended sediments as a tool to assess the impact of land occupation in water bodies: a case of Barigui Watershed (Southern Brazil)

Suspended sediments were collected to examine the organic carbon content and n-alkanes in order to assess the impact on water bodies caused by soil and land occupation. For this, samples from distinct areas based on the level of land occupation of the Barigui Watershed and different areas under the influence of human activities were examined. The number of industries increasing along the river was also considered. Twenty-two sediment samples were collected using a time-integrated sediment sampler. Samples were extracted with dichloromethane:methanol (DCM:methanol) (2:1) in an ultrasound bath, treated and injected using gas chromatography coupled with mass spectrometry (GC-MS) for separation and quantification. Twenty-one n-alkanes were identified and were used to track both biogenic and anthropogenic inputs. The concentration of total n-alkanes varied from 38.72 to 222.76 µg g^-1, due to the impact of urbanization. Diagnostic indexes indicated high numbers of plants, bacteria and petroleum as n-alkanes sources. The following results were obtained using: carbon preference index (CPI), 1.96-2.22 (rainy season) and 2.12-5.80 (summer season); average chain length (ACL), 30.37-31.17 (rainy season) and 30.05-30.50 (summer season) and terrigenous aquatic ratio (TAR), 0.39-5.47 (rainy season) and 2.98-5.06 (summer season); n-alkanes had two main sources: terrestrial plant and petroleum. It is clear that the source of n-alkanes is different in each season (rainy and dry) demonstrated by n-alkanes occurrence. During the rainy season, there was an increase in organic matter of oil origin which was mainly associated with the increased runoff and rain drainage. Finally, the input of organic matter associated with land occupation and erosion can be distinguished by higher concentration in the most urbanized site (PB).

A Quantitative Study on the Ethnobotanical Knowledge about Wild Edible Plants among the Population of Messiwa

Background

The preservation of traditional knowledge of wild edible plants (WEPs) is one of the challenges to the sustainability of natural resources. Therefore, it is crucial to assess the traditional knowledge of WEPs in relation to some socio-demographic and economic factors.

Methods

The survey was conducted among the Messiwapopulationthrough a semi-structured questionnaire. The first part of the questionnaire concerns socio-demographic and economic information, while the second part concerns the plants recognized and used by the informant. The recognition frequency (RF), the use frequency (UF), the general consumption frequency(CF), the recent consumption frequency (RCF), and the correlation between these frequencies were evaluated. A comparison of means was also used to compare informant's knowledge according to their socio-demographic and economic status.

Results

The three species;Foeniculum vulgare, Ziziphus lotus, and Malva sylvestris were the most recognized (FR = 1) and the most used (FU = 1). The consumption frequency (CF) and the recent consumption frequency (RCF) for Foeniculum vulgare were 1 and 0.9, respectively. Taraxacum getulum, Calendula arvensis and Cyperus rotundus were the least recognized (FR= 0.16; 0.16; 0.48) and least used (FU = 0.3; 0.3; 0.4) species, respectively. The informants who showed a high level of traditional knowledge on WEPs were housewives, with a low level of schooling and at least 45 years old.

Conclusion

Despite the decline in traditional knowledge about wild edible plants, some populations preserve this knowledge, especially among the elderly. Therefore, documentation of this knowledge is necessary through ethnobotanical and ethnomedicinal studies.

Assessment of current reservoir sedimentation rate and storage capacity loss: An Italian overview

Sedimentation has a prominent impact on the functionality and lifetime of reservoirs and is a growing concern for stakeholders. Various parameters influence sedimentation caused by soil erosion. Here we have examined fifty Italian reservoirs to determine sedimentation rates and storage capacity loss. The reservoirs studied have an average age of 78 years as of 2021, with the highest loss of capacity observed, equal to 100%, for Ceppo Morelli. For the fifty Italian catchments covering north, south, central and islands of Italy, we found the mean annual sediment yield varying between 17-4000 m³/km². year. Six of fifty reservoirs studied (Quarto, Colombara, Ceppo Morelli, Fusino, Vodo and Valle di Cadore) are already in a very critical situation in terms of storage capacity loss. Out of the fifty reservoirs, half of them will reach their half-life year by 2050. For example, for the Fusino reservoir located in northern Italy, we observed a loss of 90% of the storage volume as of 2020 with respect to its operation year 1974, compared to 6% in 2015 as available in literature. Modelling the sediment delivery ratio (SDR) is an open question, due to the lack of adequate data and uncertainties about the variability in hydrological, geomorphological, climate and landcover parameters. Here, we addressed the issue with a simplified multiple regression approach based on sediment delivery ratio values retrieved by the RUSLE model. We found different multi regressions for reservoirs belonging to the Alpine and Apennine regions. This analysis offers a starting point for the management and prioritization of adaptation and remediation policies necessary to address reservoir sedimentation.

Application of deep learning models to detect coastlines and shorelines

Identifying and monitoring coastlines and shorelines play an important role in coastal erosion assessment around the world. The application of deep learning models was used in this study to detect coastlines and shorelines in Vietnam using high-resolution satellite images and different object segmentation methods. The aims are to (1) propose indicators to identify coastlines and shorelines; (2) build deep learning (DL) models to automatically interpret coastlines and shorelines from high-resolution remote sensing images; and (3) apply DL-trained models to monitor coastal erosion in Vietnam. Eight DL models were trained based on four artificial-intelligent-network structures, including U-Net, U2-Net, U-Net3+, and DexiNed. The high-resolution images collected from Google Earth Pro software were used as input data for training all models. As a result, the U-Net using an input-image size of 512 × 512 provides the highest performance of 98% with a loss function of 0.16. The interpretation results of this model were used effectively for the coastline and shoreline identification in assessing coastal erosion in Vietnam due to sea-level rise in storm events over 20 years. The outcomes proved that while the shoreline is ideal for observing seasonal tidal changes or the immediate motions of current waves, the coastline is suitable to assess coastal erosion caused by the influence of sea-level rise during storms. This paper has provided a broad scope of how the U-Net model can be used to predict the coastal changes over vietnam and the world.

Transport and accumulation of plastic particles on the varying sediment bed cover: Open-channel flow experiment

Contamination of sea bottom sediments by microplastics is widely confirmed, but the reasons for its patchiness remain poorly understood. Laboratory experiments are reported where combined sets of various plastic particles, different by shape, size, density, and flexibility, were transported by the step-wise increasing open-channel flow over the bottom covered with natural sediment of increasing grain size. For every particular flow velocity, observations revealed the recurrent formation of relatively narrow retention areas, where plastic particles lingered for some time in their motion. These areas follow the line of change of the sediment type from finer to coarser grains. It is shown that contact friction drives the retention of a particle at finer sediments, while particle/sediment-grain interaction becomes of importance when particles and sediment grains are of similar sizes. The presence of this effect can be expected for a relatively wide range of natural conditions.

Dual function of quercetin as an MMP inhibitor and crosslinker in preventing dentin erosion and abrasion: An in situ/in vivo study

OBJECTIVE

The aim of the present study was to evaluate the in situ/in vivo effect of quercetin on dentin erosion and abrasion.

METHODS

Human dentin blocks (2 × 2 × 2 mm) were embedded and assigned to 6 groups: 75 μg/mL, 150 μg/mL and 300 μg/mL quercetin (Q75, Q150, Q300); 120 μg/mL chlorhexidine (CHX, positive control); and deionized water and ethanol (the negative controls). The specimens were treated with the respective solutions for 2 min and then subjected to in situ/in vivo erosive/abrasive challenge for 7 d as follows: in vivo erosion 4 times a day and then in vivo toothbrush abrasion after the first and last erosive challenges of each day. Dentin loss was assessed by profilometry. An additional dentin specimen was used to evaluate the penetration depth of quercetin into dentin by tracking the spatial distribution of its characteristic Raman peak. Moreover, dentin blocks (7 × 1.7 × 0.7 mm) were used to detect the impact of quercetin on dentin-derived matrix metalloproteinase (MMP) inhibition by in situ zymography, and the inhibition percentage (%) was calculated. Additionally, the potential collagen crosslinking interactions with quercetin were detected by Raman spectroscopy, and the crosslinking degree was determined with a ninhydrin assay. Fully demineralized dentin beams (0.5 × 0.5 × 10 mm) were used to evaluate the impact of quercetin on the mechanical properties of dentin collagen fibre by the ultimate micro-tensile strength test (μUTS). The data were analysed by one-way analysis of variance and Tukey's test (α = 0.05).

RESULTS

Compared to the negative controls, all treatment solutions significantly reduced dentin loss. The dentin loss of Q150 and Q300 was significantly less than that of CHX (all P < 0.05). The amount of quercetin decreased with increasing dentin depth, and the maximum penetration depth was approximately 25-30 µm. In situ zymography showed that quercetin significantly inhibited the activities of dentin-derived MMPs. The inhibitory percentages of Q75 and Q150 were significantly lower than that of CHX (all P < 0.05), but no significant difference was found between Q300 and CHX (P = 0.58). The collagen crosslinking interactions with quercetin primarily involved hydrogen bonding and the degree of crosslinking increased in a concentration-dependent manner. Statistically significant increases in μUTS values were observed for demineralized dentin beams after quercetin treatment compared with those of the control treatments (all P < 0.05).

SIGNIFICANCE

This study provides the first direct evidence that quercetin could penetrate approximately 25-30 µm into dentin and further prevent dentin erosion and abrasion by inhibiting dentin-derived MMP activity as well as crosslinking collagen of the demineralized organic matrix.

Effect of citric acid erosion on enamel and dentin and possible protection by a novel bioactive borate adhesive system

OBJECTIVES

This study examined the ability of a borate adhesive to protect enamel/dentin surfaces from acidic erosion and its effect on the shear bond strength (SBS) of enamel/dentin to resin composite.

MATERIALS AND METHODS

180 human enamel/dentin specimens were utilized. Enamel buccal surfaces were etched with phosphoric-acid then divided into: (EBG) borate glass adhesive group; (ERS) resin-adhesive system group; (EF) fluoride gel 1.23% group, and enamel control (EC) group; followed by bonding to orthodontic-buttons. The dentin specimens were conditioned by EDTA (Ethylene-diamine-tetra-acetic acid) and divided into: (DBG) borate glass resin, (DRS) resin adhesive; (DDA) group had a dentin-desensitizing agent VivaSens (VivaDent, Liechtenstein) and (DC) control group. The treated enamel/dentin specimens had their SBS to composite. The enamel/dentin specimens were exposed to 1% citric acid (18 min). Enamel/dentin specimens were examined by (SEM/EDS) scanning-electron-microscope equipped with electron-dispersive-spectroscopy and (FTIR/ATR). Analysis-of-Variance (ANOVA) was used to compare the SBS and Wilcoxon-signed-rank test was used to compare the enamel/dentin areas protected by the applied agents before/after erosion (p = 0.05).

RESULTS

There was no significance difference in SBS among all groups except for (DDA) group that showed significant decrease p < 0.05. (EBG) and (DBG) groups were the only groups significantly protected enamel and dentin from erosion p < 0.05. FTIR/ATR showed that erosion altered the chemical structure of (DRS), (DDA), and (DC) groups but did not affect the other enamel/dentin groups. Degree of conversion of the borate-adhesive system was acceptable.

CONCLUSION

The Borate adhesive system released calcium and phosphate compounds that decreased the erosive activity of the citric acid resulting in protecting simulated dentin-hypersensitive areas and enamel from erosion without affecting the SBS to resin-composite.

CLINICAL SIGNIFICANCE

A Borate adhesive system can be adopted as a therapeutic agent in a fully integrated program for protecting dentin-hypersensitive areas and in enamel next to orthodontic fixed appliances.

Microplastics in agricultural soils from a semi-arid region and their transport by wind erosion

Despite the importance of agricultural soils, little is known about the fate of microplastics (MPs) in this environment. In the present study, MPs have been determined in soils and wind-eroded sediments from two vegetable-growing fields in the Fars province of Iran, one using plastic mulch for water retention (Field 1) and the other using wastewater for irrigation (Field 2). MPs were heterogeneously distributed in the surface (0-5 cm) and subsurface (5-15 cm) soils of both fields, with a maximum concentration overall of about 1.1 MP g^-1 and no significant differences in concentrations between either fields or depths. Fibres represented the principal shape of MPs, but spherules, presumably from wastewater, also made a significant (∼25%) contribution to MPs in Field 2. Analysis of selected samples by Raman spectroscopy and scanning electron microscopy revealed that polyethylene terephthalate (PET) and nylon were the most abundant polymers and that MPs exhibited varying degrees of weathering. Concentrations of MPs in this study are within the range reported previously for agricultural soils, although the absence of PET observed in earlier studies is attributed to the use of insufficiently dense solutions to isolate plastics. Deployment of a portable wind tunnel revealed threshold wind velocities for soil erosion of up to 7 and 12 m s^-1 and MP erosion rates up to about 0.4 and 1.1 MP m^-2 s^-1 for Fields 1 and 2, respectively. Erosion rates are considerably greater than published depositional rates for MPs and suggest that agricultural soils act as both a temporary sink and dynamic secondary source of MPs that should be considered in risk assessments and global transport budgets.

The anthropogenic fallout radionuclides in soils of Mount Khuko (the Western Caucasus) and their application for determination of sediment redistribution

The purposes of this study are to determine the content and origin of anthropogenic fallout radionuclides (FRN) in soils of Mount Khuko, located in the western sector of the Caucasus Mountains and to assess the possibility to use them for evaluation of sediment redistribution for the alpine grasslands,. The field study was carried out in August 2019 near the top of Mount Khuko, located in the western part of the main Caucasus Mountain Ridge. Integral and incremental soil samples were collected from the different morphological units of the studied area. The content of ¹³⁷Cs and ²⁴¹Am in soil samples was evaluated using laboratory gamma-spectrometry. A part of samples was selected for Pu isotopes extraction and then alpha-spectrometric analysis. It was established that the ¹³⁷Cs contamination of soils in the studied area has at least two sources of origin. The first source is the ¹³⁷Cs bomb-derived fallout after the bomb tests in 1950-60th, which is widespread across the globe. The second source is ¹³⁷Cs Chernobyl-derived fallout High random variability (Cv = 25-42%) was found within reference sites, located at the undisturbed areas on the local flat interfluves due to high variability of soil characteristics (grain size, density, organic matter content etc.). However minimum spatial variability (range 12,2-14,3 kBq/m²) was identified for the mean value of ¹³⁷Cs inventories for all 5 reference sites located in the different parts of the studied area. It is difficult to separate individual peaks of the bomb-derived and Chernobyl-derived ¹³⁷Cs falloutin sediment sinks with low sedimentation rates. Application ^239,240Pu as an additional chronological marker allows to identify the origin of above mention peaks in the soils of alpine grasslands and of dry lake bottom.

Wildfires trigger multi-decadal increases in sedimentation rate and metal loading to subarctic montane lakes

We evaluated how two large wildfires affected the sedimentation rate and accumulation of lead (Pb), mercury (Hg), and cadmium (Cd) in sediment of four subarctic montane lakes in the Yukon, Canada. The wildfires occurred 60 and 20 years (1958, 1998) before sediment collection in 2018. Site-specific fire exposure was inferred from the charcoal accumulation histories in the lake sediments and the burned catchment area was determined from historical fire maps. The two major wildfires caused a two to five-fold increase in sedimentation rates and a two to eight-fold increase in sediment metal accumulation rates in Little Fox Lake. The mass accumulation rates of metals in Little Fox Lake sediment increased by a maximum of 2.7-4.7 mg Pb m^-2 yr^-1, 19-29 μg Hg m^-2 yr^-1 and 37-114 μg Cd m^-2 yr^-1 following wildfires. Modelling using elemental ratios of lithogenic sources suggested a large proportion of the Pb and Hg accumulating in post-fire sediment was from remobilized legacy anthropogenic pollution. In contrast, Cd fluxes were consistent with variation in catchment weathering. Impacts of wildfires were visible but more muted in the sediment of Little Braeburn Lake, whereas Fox Lake and Grayling Lake sediments showed little to no wildfire impact and served as a reference for external (long-range) metal deposition. Major changes to lake sediment geochemistry in Little Fox Lake were caused by the lack of vegetation and soil recovery in the catchment following the severe 1998 fire. Wildfire impacts were persistent in the lake more than 20 years after the last fire, with no sign of a return to pre-fire Pb, Hg, and Cd accumulation rates. This study shows that wildfires in northern montane catchments can significantly increase the rate of metal accumulation in affected lakes, thereby impeding recovery from reductions in anthropogenic air emissions of these metals.

The environmental, economic, and social development impact of desertification in Iraq: a review on desertification control measures and mitigation strategies

The threat of desertification is considered a global concern that occurs in many environments in different parts of the world, where extensive lands are transformed gradually into desert or semi-desert areas, and this causes economic and health issues. Iraq and many other parts of the Middle East are facing desertification threats in the last twenty years. Despite the significance of this issue, relevant reviews are scarce. The removal of vegetation cover, overgrazing, deforestation in times of war, poor irrigation practices and water scarcity are some of the main causes of desertification in Iraq. Fighting desertification requires cooperative efforts including the utilization of innovative practices, biotechnological approaches, restoration of oases, continuous reforestation, and rehabilitation of agricultural lands. The objective of this review article is to discuss the causes of desertification and land degradation in Iraq, highlighting the main natural and human factors involved, and the consequent impact on the national security, economy, society, and health. In addition, it suggests recommendations for policies and actions that can be integrated to mitigate this problem.

The resilience of soil erosion rates under historical land use change in agroecosystems of Southern Spain

Land use change (LUC) is identified as one of the main drivers of soil erosion in the Mediterranean. However, very little information exists regarding the relationship between land use and erosion over longer time periods and on regional scales. We quantified the LUC in Southern Spain between 1956 and 2018, examining its effect on soil erosion and assessing the mitigation role of the permanent grassland (PG). The land use influence on erosion is represented by the RUSLE's C-factor, which was modelled using the Monte Carlo Method (MCM) based on historical LUC. Moreover, future LUC scenarios by 2038 were developed by binary logistic model (scFS) and by a complete conversion of PG to cropland (scPC), permanent crop (scPP) and forest and natural (scFP). Historically, Southern Spain has experienced an impressive intensification of its agricultural system. While soil loss variation is noted within the classes, no big variation is observed in cumulative erosion on a regional scale. The underlying reasons for this resilience are multifold, but mainly attributed to the fact that a small fraction of the total surface (20%), dominates total erosion (67%). The C-factor decrease in this area displays a LUC towards forest and natural area, suggesting an agriculture abandonment. On the other hand, the agricultural intensification that has taken place in the remainder of the area, contributes much less to overall soil erosion. Future LUC scenarios illustrate the importance of PG for erosion mitigation. scFS scenario does not project major changes. However, scCP and scPP, show an abrupt increase in regional erosion by 13% and 14%, while scFP shows a negligible reduction of erosion close to 0%. This allows to quantify the erosion mitigation offered by maintaining the PG and should be taken into account for future agricultural policy.

Mesh plug erosion into the small intestine after inguinal hernia repair: A case report

BACKGROUND

Mesh plug (MP) erosion into the intra-abdominal organs is a rare but serious long-term complication after inguinal hernia repair (IHR), and may lead to aggravation of symptoms if not treated promptly. It is difficult to diagnose MP erosion as there are no obvious specific clinical manifestations, and surgery is often needed for confirmation. In recent years, with the increased understanding of postoperative complications, MP eroding into the intra-abdominal organs has been a cause for concern among surgeons.

CASE SUMMARY

A 50-year-old man was referred to the Department of General Surgery with the complaint of abdominal pain in the right lower quadrant for 2 d. He had a surgical history of right open IHR and partial thyroidectomy performed 20 years and 15 years ago, respectively. Computed tomography revealed a circinate high-density image with short segmental thickening of the ileum stuck to the abdominal wall, and no evidence of recurrent inguinal hernia. Laparoscopic abdominal exploration confirmed adhesion of the middle segmental portion of the ileal loop to the right inguinal abdominal wall; the rest of the small intestine was normal. Further exploration revealed migration of the polypropylene MP into the intraperitoneal cavity and formation of granulation tissue around the plug, which eroded the ileum. Partial resection of the ileum, including the MP and end-to-side anastomosis with an anastomat, was performed.

CONCLUSION

Surgeons should aim to improve their ability to predict patients at high risk for MP erosion after IHR.

Effect of erosive challenge with HCl on restorative materials

OBJECTIVE

Investigate the effect of erosive challenge with hydrochloric acid (HCl) on the surface of five different restorative materials.

MATERIAL AND METHODS

Ten plates of five restorative materials (Admira Fusion, Activa BioActive-Restorative, Charisma, Equia Forte HT Fil/EF, Filtek Universal Restorative/FU) were obtained. Half of the plate surfaces was covered with an adhesive tape, creating a control area, and the other side was submitted to the HCl (0.06 M HCl; pH 1.2; at 37 °C; for 30 h). Plates with control and HCl-treated areas were analyzed regarding the surface roughness (Sa), roughness profile (Rv), surface loss (SL), microhardness (MI), and gloss (GL) (n = 10). Surface morphology was analyzed by SEM and chemical elements were identified by EDX (n = 5). Data were evaluated by ANOVA and Tukey's test (α = 0.05).

RESULTS

Most materials were not affected by HCl. FU showed the lowest Sa and Rv, and the highest GL after HCl. On the other hand, EF presented the highest Sa, Rv, and SL, and the lowest GL. The MI of materials was not changed after HCl. Topographical and chemical alterations were observed after HCl only for EF.

CONCLUSIONS

The composites showed minor surface changes after HCl, which was not observed for the glass ionomer cement (EF). FU presented the best performance regarding the parameters evaluated.

CLINICAL RELEVANCE

The effects of erosive challenge with HCl on composites were minimal, while the glass ionomer cements might not be indicated as restorative material for patients with gastroesophageal reflux disease.

Geochemistry and sedimentary photopigments as proxies to reconstruct past environmental changes in a subtropical reservoir

Sediment cores were used to establish past environmental impacts associated with eutrophication, erosion and metal contamination in the subtropical Atibainha reservoir (São Paulo State, Brazil). We hypothesize that: (1) the levels of nutrients, determined by a spectrophotometric method, reflect the contributions of these elements over time and (2) changes in sedimentation rates, determined by ²¹⁰Pb geochronology, and metal flows, determined by ICP-AEOS, are related to anthropic activities. Stratigraphic changes in the analysed variables were used to divide the sediment cores into three intervals, according to PCA and cluster analysis (Euclidian distances, Ward's method). Interval I, composed by the period prior to operation of the reservoir, was influenced by organic matter levels. Interval II, between 1967 and 1993 (PC2: 14.94% of the total variability), a period of minor impacts, was mainly influenced by Mn (eigenvalue of 0.71) and Zn (0.74). Interval III, which included sediment deposited between 1993 and 2015 (PC1: 60.28% of the total variability), was influenced by the highest levels of the pigments lutein (0.86), zeaxanthin (0.90) and fucoxanthin (0.65), together with total nitrogen (0.78) and sedimentation rate (0.91), suggesting changes in the phytoplankton community composition probably associated to the intensification of eutrophication and erosion processes. Despite the limitations of applying paleolimnological techniques in reservoirs and the use of pigments as proxies in regions with higher temperatures, it was observed that the anoxic conditions and the aphotic environment in the hypolimnion acted to preserve pigments associated with the groups Chlorophyta (lutein), Cyanobacteria (zeaxanthin) and Bacillariophyta (fucoxanthin). The isolated analysis of nutrients was not sufficient to make conclusive inferences regarding the eutrophication history, since the levels of TP tended to decrease over time, in contrast to an increase in the levels of TN. Despite intensification of eutrophication and erosion, associated to anthropic activities, no signs of metal contamination were recorded.

Agroforestry for controlling soil erosion and enhancing system productivity in ravine lands of Western India under climate change scenario

Soil erosion in semi-arid climate leading to the development of ravine lands is the most severe form of land degradation. Ravine lands are formed when soil is not fully covered by the vegetation throughout the year and sporadic vegetation is not able to bind the soil particles from being washed away by rainfall. Throughout the globe, ravine lands have severe limitations for their rehabilitation and sustainable utilization as a consequence of its unique topographical features. Climatic and edaphic stresses make crop production extremely challenging in these lands. Practicing sole cropping promotes erosion, produces low crop yield, utilizes high energy, and emits greenhouse gasses (GHGs). Tree cultivation either sole or in combination with crops (agroforestry) has a strong potential to control erosion, produce sustainable economic yield, reduce energy consumption, and sequester greater amount of atmospheric carbon dioxide in biomass and soil carbon pools besides providing various ecosystem services. Therefore, practicing agroforestry could be a promising approach to obtain the greater environmental and economic benefits in the ravine lands. The present study was conducted on three systems, i.e., sole crop cultivation (cowpea + castor), agroforestry (sapota + cowpea + castor), and sole sapota plantation, to evaluate their impact on soil erosion, runoff, system productivity, profitability, energetics, and carbon sequestration during the 4-year period (2017-2020). The results revealed that agroforestry reduced the total soil loss and runoff by 37.7% and 19.1%, respectively, compared to the sole crop cultivation. Likewise, the highest system productivity as cowpea equivalent yield (CEY) was obtained under agroforestry system that increased the CEY by 162% and 81.9%, compared to sole crop and sole tree plantation, respectively. The climate change mitigation potential in terms of net carbon balance was observed highest in sole tree plantation (8.4 t/ha) followed by agroforestry system (5.9 t/ha) and lowest in sole cropping system (-2.8 t/ha). Therefore, an agroforestry system could be recommended for controlling soil erosion, improving system productivity and profitability, and reducing energy consumption as well as mitigating climate change in ravine lands.

Conjunctival erosion following a PRESERFLO® MicroShunt procedure

Purpose

We describe a case of conjunctival erosion following a PRESERFLO® MicroShunt procedure, and the subsequent revision surgery.

Observations

Conjunctival erosion was noted overlying the MicroShunt implant at postoperative week 11, 8 weeks following a bleb needling procedure for bleb encapsulation. A brisk leak was observed at the site of erosion. The patient underwent a subsequent revision procedure with repositioning of the MicroShunt implant and mitomycin C (MMC) application.

Conclusion and importance

Conjunctival erosion may be a relatively rare but important complication following MicroShunt surgery and may arise from a variety of risk factors. Extra care should be taken during bleb needling in the context of MicroShunt, and needling should be directed posteriorly, beyond the distal tip of the MicroShunt.

Investigating the sources and dynamics of naturally occurring radioactive material (NORM) in the Red Deer River, Alberta, Canada

Distinguishing between natural and anthropogenic controls on the proportions of naturally occurring radioactive materials (NORMs) in the environment is important for water resource management. In this study, the dynamics of uranium (U) and thorium (Th), two of the most prominent NORM elements, were investigated in the Red Deer River basin using monitoring data collected from 2015 to 2018. More than twofold increases in median proportions of total U (from 0.73 to 1.53 µg/L) and Th (from 0.008 to 0.104 µg/L) were observed for sites located downstream of the Steveville badlands, an area of highly erodible bedrock that a ~ 300 km section of the river flows through. Input is highly variable, coinciding mainly with increases in total suspended solids during intense rainstorms in the late summer. In-depth examination of monitoring data through factor analysis, multiple linear regression, mass balance calculations, and land use analysis highlights the importance of erosion and subsequent particle transport along river banks in the badlands area on the distribution of total U and Th, while also revealing that groundwater-surface water interaction affects proportions of dissolved U throughout the river. No significant influence from industry or land use on U and Th export was found, and proportions of U and Th in water and suspended sediment are within the natural ranges expected for surface waters and sediments/soils. Methodology employed in this study provides a basic framework for analysis of environmental monitoring datasets, which can be employed in the absence of radiochemical data to study the fate, transport, and sources of NORMs.

Response of long- to short-term tidal inlet morphodynamics on the ecological ramification of Chilika lake, the tropical Ramsar wetland in India

The long- to short-term morphodynamic response in low-lying coastal wetlands raises serious concerns worldwide about the loss of their biodiversity and ecological ramifications due to change in tidal amplitude and cyclonic events. One such place worth studying is Chilika lake, India, a prominent Ramsar site, the largest brackish water lagoon in Asia, and the second-largest coastal lagoon in the world. It experiences frequent cyclone landfalls and strong littoral drift that tends to open/close the tidal inlet. The goal of this study was to analyze the response of slow onset events such as long- (1952-2020) to short-term (~annual scale from 1989 to 2020) tidal inlet movement, shoreline change (1990-2020 with almost every five-year interval), spit morphodynamics (~annual scale from 1989 to 2020) on ecological ramification in Chilika lake as well as the implications of sudden onset event such as cyclonic landfall. In this study, we used the Digital Shoreline Change Analysis System (DSAS) to compute the statistics of shoreline change rate by calculating end point rate (EPR) values for short-term shoreline change (1990, 1995, 2000, 2005, 2011, 2016, and 2020) and weighted linear regression (WLR) for long-term shoreline change (1990-2020). The results show that Chilika lake experienced both erosion and accretion processes with a remarkably high erosion rate of 19.87 m year^-1 and accretion of 16.91 m year^-1 during a long-term scale (1990-2020). The average erosion and accretion rates were 2.25 m year^-1 and 4.67 m year^-1, respectively, during the past three decades (1990-2020). The short-term analysis suggests that the highest mean erosion of 4.37 m year^-1 occurred during 2005-2011, mainly due to cyclonic storms, reduction in sediment discharge, and lunar eclipse, which induced tide with very high amplitude in August 2008. Overall, the annual scale analysis of tidal inlet shows a shifting trend towards the northward side even after the artificial opening of an inlet in 2000. It can be ascribed mainly to the prevalent direction of longshore drift along this coast. This study observed that the landfall of cyclones significantly affects the spit morphodynamics and opening of the tidal inlet, which defines the inflow of the seawater into the lagoon and further substantial impacts on the ecological ramification. The current study's methodology can be extended to comprehend the response of long- to short-term changes of the tidal inlet, shoreline, and spit morphodynamics on the ecological ramification of coastal lagoons worldwide along with impacts of sudden-onset events caused by cyclonic landfall.

Soil erosion and sediment transport under climate change for Mera River, in Italian Alps of Valchiavenna

Erosion is a main form of soil degradation, with severe consequences on slope stability and productivity, and erosion studies are required to predict possible variations of such phenomena, also under climate change scenarios. Here we estimated distributed soil erosion within Valchiavenna valley in the Rhaetian Alps, drained by Mera river, and covering Italy, and Switzerland. We used a Dynamic-RUSLE (D-RUSLE) model, which provides spatially distributed estimates of soil erosion explicitly considering snow dynamic (accumulation/melting) and snow cover, and vegetation seasonality. The model was tuned here during 2010-2019, and validation was pursued using river turbidity data, used to assess riverine sediment transport. The model parameter R-factor for rainfall erosivity was estimated using a hydrological model Poli-Hydro, properly set up in the study area. C-factor for land cover was assessed against land cover maps, with seasonally variable Normalized Difference Vegetation Index from satellite images, to account for variable vegetation stage, and large leaf cover in summer. The K-factor related to erosion susceptibility was evaluated through soil texture and organic content. LS-factor depending on slope was assessed using a DTM. Poli-Hydro and D-RUSLE models were then used to project forward potential soil erosion under climate change scenarios until 2100. Climate series (temperature, precipitation) were generated using 4 shared socio-economic pathways (SSPs) of the Sixth Assessment Report of the IPCC, with 3 global circulation models, properly downscaled locally. We analysed expected soil erosion during 2051-2060, and 2091-2100. We found increase of potential soil erosion, with exception of the EC-Earth model for the SSP2.6. Erosion would especially increase in winter, in response to smaller snow accumulation, and larger liquid rainfall share thereby, and decrease in summer, as due to decreased precipitation. Our results suggest the need for adaptation strategies to counteract increasing soil loss in the future, and may highlight most critical areas of intervention.

Degrading permafrost river catchments and their impact on Arctic Ocean nearshore processes

Arctic warming is causing ancient perennially frozen ground (permafrost) to thaw, resulting in ground collapse, and reshaping of landscapes. This threatens Arctic peoples' infrastructure, cultural sites, and land-based natural resources. Terrestrial permafrost thaw and ongoing intensification of hydrological cycles also enhance the amount and alter the type of organic carbon (OC) delivered from land to Arctic nearshore environments. These changes may affect coastal processes, food web dynamics and marine resources on which many traditional ways of life rely. Here, we examine how future projected increases in runoff and permafrost thaw from two permafrost-dominated Siberian watersheds-the Kolyma and Lena, may alter carbon turnover rates and OC distributions through river networks. We demonstrate that the unique composition of terrestrial permafrost-derived OC can cause significant increases to aquatic carbon degradation rates (20 to 60% faster rates with 1% permafrost OC). We compile results on aquatic OC degradation and examine how strengthening Arctic hydrological cycles may increase the connectivity between terrestrial landscapes and receiving nearshore ecosystems, with potential ramifications for coastal carbon budgets and ecosystem structure. To address the future challenges Arctic coastal communities will face, we argue that it will become essential to consider how nearshore ecosystems will respond to changing coastal inputs and identify how these may affect the resiliency and availability of essential food resources.

Assessment of impacts to the sequence of the tropical cyclone Nisarga and monsoon events in shoreline changes and vegetation damage in the coastal zone of Maharashtra, India

The tropical cyclones impact both the eastern and western coasts of India, causing severe socio-environmental problems. This study analyzed shoreline changes and vegetation degradation caused by cyclone Nisarga and monsoon events in Maharashtra coastal zone and Mumbai region, India. In this study, the shoreline change was studied using the Net Shoreline Movement (NSM) statistical technique embedded in the digital shoreline analysis system (DSAS) tool. The effects of the cyclone on the vegetation were mapped using the Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and the rainfall distribution from Global Precipitation Measurement (GPM) data. The correlation between rainfall data and vegetation loss was analyzed using geographically weighted regression. The results also show that 90% of the events were concentrated in the 80-300 mm classes, being classified as sudden increases. This cyclone caused erosion in 56.32% of the shoreline; the highest erosion level was observed along the coastal zone of Maharashtra (near Mumbai city). Cyclone Nisarga has also impacted the vegetation loss most prominently in the region, with mean EVI in pre-cyclone equal to 0.4 and post-cyclone equal to 0.2. These eco-physical studies using geospatial technology are needed to understand the behavior of changes in shoreline and vegetation and can also help coastal managers plan for resilient coastal systems after the passage of tropical cyclones.

Evaluation of different irrigation techniques on dentin erosion and smear layer removal: A scanning electron microscopy study

Aim

The purpose of the present study is to evaluate the effectiveness of different irrigation techniques EndoVac, RinsEndo, Canal CleanMax (CCMax), SonicMax, Passive Ultrasonic Irrigation (PUI), and Manual Needle Irrigation (MNI) on dentin erosion and smear layer removal using Scanning electron microscopy (SEM).

Materials and Methods

Seventy extracted single-rooted teeth were instrumented with ProTaper rotary instruments. The roots were randomly divided into six experimental groups (n = 10): EndoVac, RinsEndo, CCMax, SonicMax, PUI, and MNI. Final irrigation was performed with NaOCl followed by ethylenediaminetetraacetic acid and NaOCl. Six roots served as control and were irrigated with only NaOCl. Next, the roots were sectioned in a buccolingual direction and the halves were examined by SEM. Smear layer and erosion scores were recorded in the cervical, middle and apical third of the roots. Data analysis was performed using the Kruskal-Wallis and Mann-Whitney U-tests with a level of significance α = 0.05.

Results

PUI had the greatest amount of smear layer compared to other groups (P < 0.001). However, SonicMax had the greatest degree of erosion compared to RinsEndo, MNI, PUI, and EndoVac groups (P < 0.001) and CCMax group (P < 0.05).

Conclusions

RinsEndo and EndoVac techniques left the least amount of smear layer while causing erosion the least compared to CCMax, PUI, and MNI techniques.

Cover crop and phosphorus fertilizer management impacts on surface water quality from a no-till corn-soybean rotation

Best management practices that reduce potential phosphorus (P) loss and provide flexibility in P fertilizer management are needed to help producers protect water quality while maintaining crop yield. This study examined the impacts of P fertilizer management (no P, fall broadcast P, and spring injected P) and cover crop use on annual concentrations and loads of sediment, total P, and dissolved reactive P (DRP) in edge-of-field runoff from a no-till corn (Zea mays)-soybean (Glycine max) rotation in the Central Great Plains, USA, from September 2015 through September 2019. The spring injected P fertilizer treatment generally had 19% less total P and 33% less DRP loss compared to the fall broadcast treatment, confirming the importance of P fertilizer management as a practice for reducing P loss. The addition of a cover crop had an inconsistent effect on total P loss, with no effect in 2016 and 2017, increasing loss in 2018 by 56%, and decreasing it in 2019 by 40%. The inconsistent impact of cover crops on total P loss was related to cover crop effects on sediment loss. Although cover crop impacts on total P losses were inconsistent, the addition of a cover crop increased DRP loss in three of four years. Cover crop use consistently reduced sediment loss, with greater sediment reduction when P fertilizer was applied. Results from this study highlight the benefit of cover crops for reducing sediment loss and the continued need for proper fertilizer management to reduce P loss from agricultural fields.

Mesh-related complications and recurrence after ventral mesh rectopexy with synthetic versus biologic mesh: a systematic review and meta-analysis

Background

Ventral mesh rectopexy (VMR) is a widely accepted surgical treatment for rectal prolapse. Both synthetic and biologic mesh are used. No consensus exists on the preferred type of mesh material. The aim of this systematic review and meta-analysis was to establish an overview of the current literature on mesh-related complications and recurrence after VMR with synthetic or biologic mesh to aid evidence-based decision making in preferred mesh material.

Methods

A systematic search of the electronic databases of PubMed, Embase and Cochrane was performed (from inception until September 2020). Studies evaluating patients who underwent VMR with synthetic or biologic mesh were eligible. The MINORS score was used for quality assessment.

Results

Thirty-two studies were eligible after qualitative assessment. Eleven studies reported on mesh-related complications including 4001 patients treated with synthetic mesh and 762 treated with biologic mesh. The incidence of mesh-related complications ranged between 0 and 2.4% after synthetic versus 0–0.7% after biologic VMR. Synthetic mesh studies showed a pooled incidence of mesh-related complications of 1.0% (95% CI 0.5–1.7). Data of biologic mesh studies could not be pooled. Twenty-nine studies reported on the risk of recurrence in 2371 synthetic mesh patients and 602 biologic mesh patients. The risk of recurrence varied between 1.1 and 18.8% for synthetic VMR versus 0–15.4% for biologic VMR. Cumulative incidence of recurrence was found to be 6.1% (95% CI 4.3–8.1) and 5.8% (95% CI 2.9–9.6), respectively. The clinical and statistical heterogeneity was high.

Conclusions

No definitive conclusions on preferred mesh type can be made due to the quality of the included studies with high heterogeneity amongst them.

Ecological problems of environment mudflows and their prediction: experience of Georgia

Among the natural disasters on the planet, especially in the mountainous and foothill regions, it is widespread erosive-debris flow events, which have the most significant environmental and economic damage to humanity. Georgia is no exception. This paper aims to develop a new methodology to calculate the predictive quantities of debris flow, essential for implementing anti-debris flow measures. Based on the available data and various calculations, a completely new empirical approach has been adopted to calculate predictive quantities of debris flow spent, predicting debris flow spent in the mountains and foothill regions of Georgia. The suggested methodology reflects the physics of debris-flow processes at a very high level and can be applied to calculate debris flow in various world regions.

Quick and Simultaneous Analysis of Dissolved Active Pharmaceutical Ingredients and Formulation Excipients from the Dissolution Test Utilizing UHPLC and Charged Aerosol Detector

The objective of the study is to develop a quick and simultaneous analysis system for the dissolution of the active pharmaceutical ingredient (API) and the formulation excipient in samples from the dissolution test by UHPLC using the charged aerosol and PDA detectors. The combination of two columns for size-exclusion chromatography (SEC) and the equipment of the charged aerosol detector allowed the quick determination of various water-soluble polymers. Three model sustained-release tablets, each containing a different API of different water solubility (propranolol (soluble), ranitidine (very soluble), and cilostazol (practically insoluble)), were prepared from polyethylene oxide (PEO) matrix to verify the applicability and utility of the analysis system. The dissolution of propranolol was the same as that of PEO, indicating that the diffusion rate of propranolol was consistent with the erosion rate of the PEO and that the dissolution of PRO was based on diffusion. Ranitidine was released faster than PEO, suggesting that ranitidine was diffused through the gel layer of PEO early upon contact with the dissolution medium and before PEO gel erosion. Cilostazol was released slower as compared to PEO, indicating that cilostazol dissolution was based on the polymer's erosion. These results suggested that the analysis system developed in this study is a precise and valid tool to study the dissolution behavior of both APIs and excipients. Optimization of the SEC column for the appropriate separation of APIs and excipients makes the analysis system more efficient and convenient to study the drug release mechanisms and to design formulations.

Adhesion to eroded enamel and dentin: systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to compare the bond strength between eroded and sound permanent enamel and dentin and to assess whether bonding performance (immediate and after aging) differs between etch&rinse and self-etch adhesives and can be improved by surface pretreatment prior to bonding.

METHODS

Electronic databases (PubMed, Scopus, Embase, Web of Science, CENTRAL, LILACS, BBO) were searched by two reviewers. Random-effect meta-analyses were performed to compare bond strength to sound and eroded dental hard tissues without and with surface pretreatment prior to bonding, respectively. The effect of adhesive mode (etch&rinse vs. self-etch) and aging (immediate vs. aged) was compared using subgroup analyses. Statistical heterogeneity was assessed using Cochran's Q and I²-statistic. Funnel plots and Egger's regression intercept tests were used to evaluate publication bias. Quality and risk of bias of included studies were also assessed.

RESULTS

Fourty-seven studies (45 in vitro, 2 in situ) were included in the systematic review and meta-analyses. Erosion impairs bond strength to dentin (p < 0.001; mean difference: -10.2 MPa [95%CI: -11.9 to -8.6 MPa]), but not to enamel (p = 0.260). Surface pretreatment measures removing or stabilizing the collagenous matrix can improve dentin bond strength (maximum mean difference: +12.4 MPa). Etch&rinse and self-etch adhesives did not perform significantly different on eroded enamel (p = 0.208) and dentin (p = 0.353). The majority of studies (32 of 47) presented a medium risk of bias.

SIGNIFICANCE

Data from in vitro and in situ studies showed that erosion impairs dentin bonding of etch&rinse and self-etch adhesives and makes surface pretreatment prior to bonding of composite restorations necessary.

Wear of conventional and pre-polymerized composite materials under erosive/abrasive conditions

The aim of this study was to examine the wear of three different composite materials usable for vertical bite reconstruction under erosive/abrasive conditions and to compare them with the bovine dental hard tissues enamel and dentin in-vitro. The composite materials Filtek Supreme XTE, CeraSmart and Brilliant Crios and bovine enamel and dentin specimens were evenly allocated to five groups (n=10). Samples were firstly exposed to hydrochloric acid for 1 min, then stored for 30 min in artificial saliva. In the second step, the samples were brushed for 1 min with 100 brushing strokes each and an applied force of 2.5 N in an automated brushing device. After 60 of these erosive/abrasive cycles, wear of the samples was determined by contact profilometry. Filtek Supreme XTE showed significantly less wear (mean ± standard deviation; 0.15 ± 0.11 μm) compared to the other two composite materials (p < 0.05). No significant difference (p > 0.05) could be found between CeraSmart (0.25 ± 0.03 μm) and Brilliant Crios (0.24 ± 0.04 μm). The two bovine dental hard tissues, enamel (13.70 ± 0.94 μm) and dentin (50.08 ± 4.46 μm), each showed a significantly higher amount of wear than the three restorative materials (p <0.05). In conclusion, this study exhibited that the three composite materials, Filtek Supreme XTE, CeraSmart and Brilliant Crios, were more resistant under erosive/abrasive conditions compared to bovine enamel and bovine dentin, respectively.

4D microstructural changes in dentinal tubules during acid demineralisation

OBJECTIVE

Dental erosion is a common oral condition caused by chronic exposure to acids from intrinsic/extrinsic sources. Repeated acid exposure can lead to the irreversible loss of dental hard tissues (enamel, dentine, cementum). Dentine can become exposed to acid following severe enamel erosion, crown fracture, or gingival recession. Causing hypersensitivity, poor aesthetics, and potential pulp involvement. Improving treatments that can restore the structural integrity and aesthetics are therefore highly desirable. Such developments require a good understanding of how acid demineralisation progresses where relatively little is known in terms of intertubular dentine (ITD) and peritubular dentine (PTD) microstructure. To obtain further insight, this study proposes a new in vitro method for performing demineralisation studies of dentine.

METHODS

Advanced high-speed synchrotron X-ray microtomography (SXM), with high spatial (0.325 μm) and temporal (15 min) resolution, was used to conduct the first in vitro, time-resolved 3D (4D) study of the microstructural changes in the ITD and PTD phases of human dentine samples (∼0.8 × 0.8 × 5 mm) during 6 h of continuous acid exposure.

RESULTS

Different demineralisation rates of ITD (1.79 μm/min) and PTD (1.94 μm/min) and their progressive width-depth profiles were quantified, which provide insight for understanding the mechanisms of dentine demineralisation.

SIGNIFICANCE

Insights obtained from morphological characterisations and the demineralisation process of ITD and PTD during acid demineralisation would help understand the demineralisation process and potentially aid in developing new therapeutic dentine treatments. This method enables continuous examination of relatively large volumes of dentine during demineralisation and also demonstrates the potential for studying the remineralisation process of proposed therapeutic dentine treatments.

Monitoring and assessment of soil quality based on micronutrients and physicochemical characteristics in semi-arid submountainous Shiwalik ranges of lower Himalayas, India

Lower Shiwalik foothill ranges (Kandi regions) are dominated by different land use systems, varying in fertility status due to soil erosion owing to undulating topographical features. For assessment of soil nutrient status of study area, the soil sampling was conducted to investigate the variation in micronutrient status and physicochemical characteristics of soil. Long-range basis soil sampling was carried out in 11 blocks falling in the entire Shiwalik ranges of lower Himalaya under different land use systems (LUSs), viz., agriculture (AG), horticulture (HR), agri-horticulture (AH), grassland (GL), and agroforestry (AF) systems. A total of 440 soil samples were collected from two depths (0-15, 15-30 cm) for analysis. The results had reported that the soils were slightly acidic to slightly alkaline (6.61 to 8.10) in the whole range. Soil organic carbon (SOC) was found to be varying from very low to very high (2.43 to 10.43 g kg^-1). DTPA-extractable Fe and Mn were found to be in dominant concentrations in the soils whereas, the deficiency of Zn was found under all existing land uses. Interestingly, Fe (r = 0.62*), Cu (r = 0.44), and Mn (r = 0.35) micronutrients were positively correlated with clay content whereas Zn (r = - 0.02) was negatively correlated. Soil quality based on principal component analysis (SQI-PCA) reported clay, SOC, and Zn are major dominating parameters to be considered of soil in Shiwalik ranges.