Innovative plasticization technique for talc-powder reinforced wheat-starch biomass composite plastics with enhanced mechanical strength

N-methyl-morpholine-N-oxide (NMMO) was initially created as a plasticizer for starch to produce thermoplastic wheat starch. Subsequently, talc powder was used as a reinforcing filler to enhance the mechanical strength of thermoplastic biomass-based composite plastics. The chemical structure, crystal structure, and microscopic morphology were analyzed using Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Additionally, the thermal properties were explored through thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. The hydrated NMMO plasticizer demonstrated an outstanding plasticizing effect on starch, resulting in a composite with remarkable mechanical properties. In fact, the pure thermoplastic wheat starch plasticized with hydrated NMMO exhibited the highest mechanical strength recorded so far, with a tensile strength of up to 9.4 MPa. In addition, talcum powder displayed a noticeable reinforcing effect. When the talcum powder content reached 30 wt%, the targeted composite achieved a tensile strength of 20.5 MPa and a Young's modulus of 177.9 MPa. These values were 118 % and 48 % higher, respectively, than those of the pure thermoplastic starch sample. This innovative plasticizing method opens up a new avenue for the development of high-mechanical-strength thermoplastic biomass-based composite plastics with promising potential applications.

Clinical Value of Different Test Methods in Diagnosing Mycoplasma pneumoniae Infection in Children

This research aimed to investigate the diagnostic value of passive particle agglutination test, Mycoplasma pneumoniae (MP) culture, cold agglutination test (CAT), enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction-capillary electrophoresis fragment analysis (PCR-CEFA) for MP infection. Children with respiratory tract infections suspected to be MP infection were subjected to passive particle agglutination test, MP culture, CAT, ELISA, and PCR-CEFA. A total of 146 children (81 males, 65 females, mean age: 5.74 ± 3.32 years, and mean course of disease: 9.07 ± 5.18 days) met the inclusion criteria. The positivity rate of MP detection by MP culture was 69.18% (101/146). Using the MP culture method as the standard, higher sensitivity and positive predictive value were found in the PCR-CEFA compared with the other 3 methods. Appropriate methods are selected following the advantages and disadvantages of pathogen detection, and pediatric MP infection is analyzed by integrating various test results.

Preparation of Edible Colorant Lake Using Calcium Carbonate and β-Carotene: Structural Characterization and Formation Mechanism Study

This study prepared a novel β-carotene colorant lake using calcium carbonate (CaCO3) and investigated the lake formation process and its basic characteristics. Kinetic adsorption analysis confirmed that medium pH (9.3) and medium temperature (40 °C) were more suitable for lake preparation, while desorption occurred, possibly due to crystalline transformation of CaCO3. The isothermal analysis and model fitting results suggested that the β-carotene and CaCO3 particles combined via a monolayer adsorption process driven by physical force. Electrostatic attraction likely participated in the process due to the net negative surface charges of β-carotene dispersion and positively charged groups on the CaCO3 particle surfaces. Ethanol, ultrasonic treatment, and drying method significantly influenced the immobilization efficiency (IE) of β-carotene in the lake and light stability of the lake, without affecting its crystal form. The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) curves confirmed absorption of β-carotene onto CaCO3. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses indicated no obvious chemical bonds between β-carotene and CaCO3. Energy-dispersive spectroscopy (EDS) confirmed the presence of β-carotene on surfaces but not in the interior of the CaCO3 particles. The adsorption of β-carotene by calcium carbonate was further confirmed to be a physical adsorption on surface.

[Structural changes of the frontal cortex in depressed mice are associated with decreased expression of brain-derived neurotrophic factor]

OBJECTIVE

To investigate the changes in gray matter volume in depressive-like mice and explore the possible mechanism.

METHODS

Twenty-four 6-week-old C57 mice were randomized equally into control group and model group, and the mice in the model group were subjected to chronic unpredictable mild stimulation (CUMS) for 35 days. Magnetic resonance imaging was performed to examine structural changes of the grey matter volume in depressive-like mice. The expression of brain-derived neurotrophic factor (BDNF) in the grey matter of the mice was detected using Western blotting and immunofluorescence staining.

RESULTS

Compared with the control mice, the mice with CUMS showed significantly decreased central walking distance in the open field test (P < 0.05) and increased immobile time in forced swimming test (P < 0.05). Magnetic resonance imaging showed that the volume of the frontal cortex was significantly decreased in CUMS mice (P < 0.001, when the mass level was greater than or equal to 10 756, the FDRc was corrected with P=0.05). Western blotting showed that the expression of mature BDNF in the frontal cortex was significantly decreased in CUMS mice (P < 0.05), and its expression began to decrease after the exposure to CUMS as shown by immunofluorescence staining. The volume of different clusters obtained by voxel-based morphometry (VBM) analysis was correlated with the expression level of mature BDNF detected by Western blotting (P < 0.05).

CONCLUSION

The decrease of frontal cortex volume after CUMS is related with the reduction of mature BDNF expression in the frontal cortex.

A novel edible colorant lake prepared with CaCO3 and Monascus pigments: Lake characterization and mechanism study

Monascus pigments (MPs) were adsorbed using calcium carbonate to produce CaCO₃-MPs lakes. The fundamental properties and formation mechanism of the lakes were investigated. Results indicated that CaCO₃ displayed a high enough affinity for the MPs to form colorant lakes, while the MPs tended to transform the CaCO₃ crystals from calcite to vaterite. The adsorption of MPs by CaCO₃ followed the Freundlich isothermal model with n value higher than 1, confirming it as physical adsorption. The ΔG⁰ (-29 to ∼-33 kJ/mol) and ΔH⁰(30-55 kJ/mol) indicated that lake formation was a spontaneous and endothermic process. UV/Vis spectroscopic analysis verified the complex formation between Ca²⁺ and MPs via physical bonding, suggesting a possible attraction between the Ca²⁺ and glutamate residues of the MPs. EDS showed that the MPs were trapped inside the particles. FTIR spectroscopy and XPS further confirmed that the physical bonding was the primary driving force behind the lake formation.

Potential cerebrovascular protective functions of lycium barbarum polysaccharide in alleviating hyperglycemia-aggravated cerebral ischemia/reperfusion injury in hyperglycemic rats

OBJECTIVE

Lycium barbarum polysaccharide (LBP) is the efficient primary compound of Lycium barbarum and has been shown to alleviate hyperglycemia-aggravated cerebral ischemia/reperfusion (I/R) injury. However, the cerebrovascular changes related to diabetes mellitus (DM) and the potential cerebrovascular protective effects of LBP are still unknown. This study aimed to explore the cerebrovascular protective functions of LBP on cerebral I/R injury in diabetic rats and its potential mechanisms.

MATERIALS AND METHODS

Sprague Dawley (SD) rats were separated into three groups: the normoglycemic (NG), diabetic hyperglycemic (HG), and HG + LBP (50 mg/kg) treatment groups. A 30 min transient middle cerebral artery occlusion (tMCAO) with 24 h reperfusion was established. The neurological deficits, cerebral water content, infarct volume, and cerebrovascular permeability were assessed to evaluate the extent of cerebral injury. Histopathological alterations were assessed by hematoxylin and eosin, Nissl, immunohistochemical, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining. A transmission electron microscope was used to detect ultrastructural alterations, and a western blot was used to examine protein expression.

RESULTS

The HG rats exhibited a significant increase in neurological deficits, cerebral water content, infarct volume, cerebrovascular permeability, neural cell death, and apoptosis compared with the NG rats, and the LBP treatment alleviated these effects. Cerebrovascular structure analysis showed that the cross-sectional area (CSA) and wall thickness were remarkably altered in the HG rats compared with the NG rats. The LBP treatment protected the cerebrovascular structure and vasoreactivity by decreasing the wall thickness and increasing the CSA, α-smooth muscle actin, and endothelial nitric oxide synthase expression of cerebral vessels.

CONCLUSIONS

The intake of LBP benefits the cerebrovascular structure and vasoreactivity in diabetic rats. Our research provides a possible new strategy for treating stroke in patients with DM.

Respiratory pandemic and indoor aeraulics of classrooms

Respiratory pandemics, such as COVID19, may be transmitted by several modes. The present work focuses on the transmission through small droplets released by people from their mouth by breathing, speaking, coughing, sneering, and possibly aspirated by other people around through their respiration. An analysis of droplet evolution in simplified situations shows that the droplets reach very quickly a quasi-equilibrium temperature before encompassing an isothermal evaporation process. The removal of droplets from suspension is thus piloted by balance between evaporation and sedimentation. It is shown that ambient relative humidity is a major factor influencing the lifetime of droplets and the distance they may travel. As a consequence, and independently of any other health consideration linked to ambient humidity, it is seen that a dry air is a favourable factor for limiting risk of contamination from COVID19. Further investigation is made using computational fluid dynamics (CFD) in a classroom geometry. Several ventilation strategies are investigated: classical regulatory mechanical ventilation, open window natural ventilation and displacement natural ventilation. Ventilation has several effects which influence contamination risk: by introducing fresh air, it reduces droplet concentration; humidity released by human occupants is also limited. However, these effects are not uniform in space, and depend on ventilation strategy. Application of a dose-effect model calibrated for COVID19 to CFD results allows to estimate contamination risk. It is shown that contamination risk is higher for regulatory mechanical ventilation, and may be reduced, using natural ventilation in the absence of wind, by a factor 2.3 to nearly 3 when the teacher is sick, and by a factor 6 to 500 when a student is sick. In the presence of wind, the reduction factor is as high as 13 when the teacher is sick and 17 when a student is sick.

A pH-independent electrochemical aptamer-based biosensor supports quantitative, real-time measurement in vivo

An electrochemical aptamer-based sensor, enabling in vivo measurements of drug concentrations directly in the bladder of living rats under pH-variable conditions, was developed employing a π-extended tetrathiafulvalene (exTTF) as redox reported.

Effect of Li+/Na+ exchange on mechanical behavior and biological activity of lithium disilicate glass-ceramic

Lithium disilicate (LD) glass-ceramics with a stoichiometric composition were ion-exchanged in pure NaNO₃ or mixed NaNO₃ + KNO₃ molten salt baths below the glass transition temperature (T_g). The microstructures, surface morphologies, mechanical properties and bioactivities of the ion-exchanged glass-ceramics were studied in detail. It was found that the strength and toughness of LD glass-ceramic could be enhanced from 175 MPa to 0.96 MPa m^1/2 before ion-exchange to 546 MPa and 4.31 MPa m^1/2 respectively under a lowered ion-exchange temperature because the less stress relaxation. In addition, a gradient of Na⁺ rich layer in the surface of glass-ceramic was induced by Li⁺/Na⁺ exchange, which could be beneficial to the formation of HA (Hydroxyapatite) with nano-size porous after soaking in SBF (Simulated Body Fluid) solution and exhibited better bioactivity compared with the original LD glass-ceramic. The results might provide a reference for the strengthening and biological activation of LD glass-ceramics in bone restoration applications.

The Influence of Climate Warming and Humidity on Plant Diversity and Soil Bacteria and Fungi Diversity in Desert Grassland

Our study, which was conducted in the desert grassland of Ningxia in China (E 107.285, N 37.763), involved an experiment with five levels of annual precipitation 33% (R33), 66% (R66), 100% (CK), 133% (R133), 166% (R166) and two temperature levels (inside Open-Top Chamber (OTC) and outside OTC). Our objective was to determine how plant, soil bacteria, and fungi diversity respond to climate change. Our study suggested that plant α-diversity in CK and TCK were significantly higher than that of other treatments. Increased precipitation promoted root biomass (RB) growth more than aboveground living biomass (ALB). R166 promoted the biomass of Agropyron mongolicum the most. In the fungi communities, temperature and precipitation interaction promoted α-diversity. In the fungi communities, the combination of increased temperature and natural precipitation (TCK) promoted β-diversity the most, whose distance was determined to be 25,124 according to PCA. In the bacteria communities, β-diversity in CK was significantly higher than in other treatments, and the distance was determined to be 3010 according to PCA. Soil bacteria and fungi α- and β-diversity, and ALB promoted plant diversity the most. The interactive effects of temperature and precipitation on C, N, and P contents of plants were larger than their independent effects.

[Pulmonary mucormycosis after lung transplantation:3 cases report with literature review]

Objective: To report the risk factors, clinical characteristics and treatment courses of pulmonary mucormycosis after lung transplantation(LT). Methods: We included 3 cases with pulmonary mucormycosis after LT from March 2017 to July 2020 in the centre for lung transplantation of China-Japan Friendship Hospital. Twelve cases from Chinese and English literature from China National Knowledge Infrastructure (CNKI), China Biomedical Literature Service System and Pubmed Database from March 1980 to July 2020 were added. The risk factors, clinical characteristics and treatment courses of all cases were summarized and analyzed. Results: Pulmonary mucormycosis occurred in 1.06% (3/284) in our centre. A total of 15 cases with 12 cases from literature included 10 males and 5 females with a mean age of(47±20)years. Thirteen cases occurred after LT, and 2 cases occurred after heart-lung transplantation (HLT). Nine probable cases were diagnosed by positive isolation of the pathogen from bronchoalveolar lavage fluid or sputum. Three proven cases were diagnosed by transbronchial lung biopsy. Meanwhile, the other 3 proven cases diagnosed by CT-guided percutaneous lung biopsy, autopsy and surgical operation respectively. Ten cases (66.7%) were diagnosed with pulmonary mucormycosis within 90 days after lung transplantation. The mortality was as high as 46.67% (7/15), but if it occurred within 90 days, the mortality reached 70% (7/10). The average interval between transplantation and positive isolation of the pathogen was 112.3 (5-378) days. Conclusions: The clinical and radiographic features of pulmonary mucormycosis after LT were nonspecific. It had a high mortality, especially in those occurred within 90 days after LT. The combination of antifungal therapy and surgical resection may contribute to a better outcome of the disease.

Integrin-mediated interactions with a laminin-presenting substrate modulate biosynthesis and phenotypic expression for cells of the human nucleus pulposus

With aging and pathology, cells of the nucleus pulposus (NP) de-differentiate towards a fibroblast-like phenotype, a change that contributes to degeneration of the intervertebral disc (IVD). Laminin isoforms are a component of the NP extracellular matrix during development but largely disappear in the adult NP tissue. Exposing human adult NP cells to hydrogels made from PEGylated-laminin-111 (PEGLM) has been shown to regulate NP cell behaviors and promote cells to assume a biosynthetically active state with gene/protein expression and morphology consistent with those observed in juvenile NP cells. However, the mechanism regulating this effect has remained unknown. In the present study, the integrin subunits that promote adult degenerative NP cell interactions with laminin-111 are identified by performing integrin blocking studies along with assays of intracellular signaling and cell phenotype. The findings indicate that integrin α3 is a primary regulator of cell attachment to laminin and is associated with phosphorylation of signaling molecules downstream of integrin engagement (ERK 1/2 and GSK3β). Sustained effects of blocking integrin α3 were also demonstrated including decreased expression of phenotypic markers, reduced biosynthesis, and altered cytoskeletal organization. Furthermore, blocking both integrin α3 and additional integrin subunits elicited changes in cell clustering, but did not alter the phenotype of single cells. These findings reveal that integrin- mediated interactions through integrin α3 are critical in the process by which NP cells sense and alter phenotype in response to culture upon laminin and further suggest that targeting integrin α3 has potential for reversing or slowing degenerative changes to the NP cell.

Synovial mesenchymal stem cells effectively alleviate osteoarthritis through promoting the proliferation and differentiation of meniscus chondrocytes

OBJECTIVE

To investigate the relationship between the meniscal defect area and OA progression and explore the effect and mechanism of SMSCs cell therapy in knee osteoarthritis (OA) rat model.

MATERIALS AND METHODS

For animal experiments, knee osteoarthritis (OA) model was constructed in Sprague Dawley (SD) rats by removing the medial meniscus of the right knee. Synovial mesenchymal stem cells (SMSCs) were engrafted by injecting into the right knee cavity. For in vitro experiments, CCK-8 assay was performed to evaluate the proliferation and differentiation of BMSCs and ATDC5 cells after co-cultured with SMSCs. qRT-PCR analysis was performed to detect the expressions of chondrogenic genes in BMSCs and ATDC5 cells after co-cultured with SMSCs. Western blot analysis was conducted to detect the phosphorylations of c-Jun N-terminal kinase (JNK) and extracellular regulated protein kinases (ERK) in MAPK signaling of BMSCs and ATDC5 cells. Enzyme-linked immunosorbent assay (ELISA) was performed to detect the serum levels of interleukin (IL)-1β, IL-1β, IL-6, IL-18 and C-reactive protein (CRP).

RESULTS

Results showed that meniscus damaged area is positively correlated to serum inflammatory factor levels. In vitro study showed that the proliferation and differentiation of BMSCs and ATDC5 cells were promoted after co-cultured with SMSCs. By co-culturing with SMSCs, the MAPK signaling pathway was activated and the expression of chondrogenic markers such as aggrecan (acan), SRY-related high mobility group-box gene 9 (sox9) and Type II collagen a1 (col2a1), was up-regulated both in BMSCs and ATDC5 cells. In vivo study showed SMSCs cell therapy significantly decreased serum inflammatory factor levels and protected cartilage by upregulating the expression of chondrogenic genes of meniscus chondrocytes derived from OA rats.

CONCLUSIONS

For the first time, we found the positive correlation between meniscal defect area and OA progression and demonstrated the effect and mechanism of SMSCs cell therapy in knee osteoarthritis (OA) treatment.

Increased precipitation enhances soil respiration in a semi-arid grassland on the Loess Plateau, China

Background

Precipitation influences the vulnerability of grassland ecosystems, especially upland grasslands, and soil respiration is critical for carbon cycling in arid grassland ecosystems which typically experience more droughty conditions.

Methods

We used three precipitation treatments to understand the effect of precipitation on soil respiration of a typical arid steppe in the Loess Plateau in north-western China. Precipitation was captured and relocated to simulate precipitation rates of 50%, 100%, and 150% of ambient precipitation.

Results and Discussion

Soil moisture was influenced by all precipitation treatments. Shoot biomass was greater, though non-significantly, as precipitation increased. However, both increase and decrease of precipitation significantly reduced root biomass. There was a positive linear relationship between soil moisture and soil respiration in the study area during the summer (July and August), when most precipitation fell. Soil moisture, soil root biomass, pH, and fungal diversity were predictors of soil respiration based on partial least squares regression, and soil moisture was the best of these.

Conclusion

Our study highlights the importance of increased precipitation on soil respiration in drylands. Precipitation changes can cause significant alterations in soil properties, microbial fungi, and root biomass, and any surplus or transpired moisture is fed back into the climate, thereby affecting the rate of soil respiration in the future.

Long noncoding RNA LSINCT5 is upregulated and promotes the progression of esophageal squamous cell carcinoma

OBJECTIVE

Long stress-induced noncoding transcripts 5 (LSINCT5) has been reported to be upregulated in several human cancers and related to poor prognosis. However, its involvement in esophageal squamous cell carcinoma (ESCC) remains largely unknown. We aim to evaluate the expression and putative role of LSINCT5 on the progression of ESCC.

MATERIALS AND METHODS

LSINCT5 expression was first examined in the ESCC cell lines using RT-qPCR, and the next-generation RNA-Seq technology was employed to analyze and functionally annotate the differential gene expression before and after LSINCT5 knockdown in ESCC was made. Based on the functional annotation results, the effects of LSINCT5 knockdown on cell growth, migration, invasion, and epithelial-to-mesenchymal transition (EMT) were assessed in the ESCC cell lines. Finally, the expression and clinicopathological significance of LSINCT5 in ESCC and corresponding nontumor tissues were further explored using RT-qPCR.

RESULTS

The RT-qPCR results showed that LSINCT5 expression was significantly upregulated in the ESCC cell lines. The differential gene expression analysis by next-generation RNA-Seq showed that 138 genes were up-regulated, and 227 genes were downregulated after LSINCT5 was knocked down in the ECA 109 cells. In addition, the functional annotation revealed that the differentially expressed genes were mainly functionally involved in tight junctions, ECM-receptor interactions, and MAPK signaling pathway. Further in vitro studies indicated that the knockdown of LSINCT5 significantly suppressed proliferation, migration, invasion, and EMT in ESCC cells. Finally, a comparative study of paired ESCC and corresponding nontumor tissues showed that LSINCT5 was upregulated in the ESCC tissues, and the increased LSINCT5 expression was related to late clinical stages, large tumor sizes, and lymph node metastasis.

CONCLUSIONS

The results indicate that LSINCT5 is upregulated in ESCC and may act as an oncogene promoting the progression of ESCC.

53BP1 regulates cell cycle arrest in esophageal cancer model

OBJECTIVE

This study aims to investigate effects of checkpoint kinase, mediator of DNA damage checkpoint 1 (MDC1) and p53-binding protein 1 (53BP1) silencing on p53, checkpoint kinase 1 and 2 (CHK1 and CHK2), and CHK2-T68 expression.

MATERIALS AND METHODS

Eca109 cells were divided into untransfected Eca109, Blank-vector, MDC1-RNAi transfection, and 53BP1-RNAi transfection group. Streptavidin-peroxidase (SP) immunohistochemical assay was used to examine CHK2-T68 expression. About 4 groups were used to establish esophageal carcinoma nude-mouse models, and assigned as Eca-109 control (or Eca-109 plus 15 Gy γ-rays irradiation, Eca-109+IR), Blank-vector (or Blank-vecor+IR), 53BP1-RNAi (or 53BP1-RNAi+IR), and MDC1-RNAi group (or MDC1-RNAi+IR group) by injecting. The expression of p53, CHK1, CHK2 were evaluated using SP immunohistochemical assay.

RESULTS

53BP1 and MDC1 down-regulation significantly inhibited expression of CHK2-T68 in Eca-109 cells compared to untreated group (p<0.05). There were significant differences for CHK2-T68 expressions in different time and groups (p<0.05). 53BP1 down-regulation significantly reduced p53 and enhanced CHK1 and CHK2 expression compared to that of Eca-109 control group (p<0.05) in Eca-109 cells. 53BP1 down-regulation significantly regulated CHK1, CHK2, and p53 in xenograft nude mice models exposed to γ-ray irradiation compared to that of untreated group (p<0.05). p53 was negatively correlated with CHK1 and CHK2 in xenograft nude mice models.

CONCLUSIONS

53BP1 regulated the cell cycle arrest by modulating p53, CHK1, and CHK2 expression in both Eca-109 cells and xenograft nude mice models.

Rebuilding soil organic C stocks in degraded grassland by grazing exclusion: a linked decline in soil inorganic C

Background

Our study evaluated how soil organic carbon (SOC) and soil inorganic carbon (SIC) recovered over time in deep loessial soil as overgrazed grassland was fenced and restored.

Methods

The study was conducted in the Yunwu Mountain Nature Reserve in the Ningxia Autonomous Region of China. In it we compared soil data from three grazed grassland (G) sites, three sites that were fenced for 15 years (F15), and three sites that were fenced for 30 years (F30) as a so-called ‘space for time series’.

Results and Discussion

We compared SOC accumulation in soil up to 200 cm below the surface in G, F15, and F30 plots. An increase in SOC correlated with a decrease in soil pH, and decreased soil bulk density. However, SOC sequestration in fenced plots was largely offset by a decrease in SIC, which was closely correlated (r = 0.713, p = 0.001) with SOC-driven soil pH decline. We observed no significant increase in soil total carbon in the F15 or F30 sites after comparing them to G.

Conclusions

Our data indicate that fencing causes the slow diffusion processes to intensify the soil property changes from increased litter return, and this slow diffusion process is still active 30 years after fencing at 100–200 cm soil depths in the studied deep loessial soil. These findings are likely applicable to similar sites.

MRI Signal Intensity and Electron Ultrastructure Classification Predict the Long-Term Outcome of Skull Base Chordomas

BACKGROUND AND PURPOSE

MR imaging is a useful and widely used evaluation for chordomas. Prior studies have classified chordomas into cell-dense type and matrix-rich type according to the ultrastructural features. However, the relationship between the MR imaging signal intensity and ultrastructural classification is unknown. We hypothesized that MR imaging signal intensity may predict both tumor ultrastructural classification and prognosis.

MATERIALS AND METHODS

Seventy-nine patients with skull base chordomas who underwent 95 operations were included in this retrospective single-center series. Preoperative tumor-to-pons MR imaging signal intensity ratios were calculated and designated as ratio on T1 FLAIR sequence (R_T1), ratio on T2 sequence (R_T2), and ratio on enhanced T1 FLAIR sequence (R_EN), respectively. We assessed the relationships among signal intensity ratios, ultrastructural classification, and survival.

RESULTS

Compared with the matrix-rich type group, the cell-dense type chordomas showed lower R_T2 (cell-dense type: 1.90 ± 0.38; matrix-rich type: 2.61 ± 0.60 P < .001). The model of predicting cell-dense type based on R_T2 had an area under the curve of 0.83 (95% CI, 0.75-0.92). In patients without radiation therapy, both progression-free survival (P = .003) and overall survival (P = .002) were longer in the matrix-rich type group than in the cell-dense type group. R_EN was a risk factor for progression-free survival (hazard ratio = 10.24; 95% CI, 1.73-60.79); R_T2 was a protective factor for overall survival (hazard ratio  = 0.33; 95% CI, 0.12-0.87); and R_EN was a risk factor for overall survival (hazard ratio = 4.76; 95% CI, 1.51-15.01).

CONCLUSIONS

The difference in MR imaging signal intensity in chordomas can be explained by electron microscopic features. Both signal intensity ratios and electron microscopic features may be prognostic factors.

[Prevalence and risk factors of ischemic stroke in rural areas of Liaoning province]

Objective: To explore the prevalence and risk factors of ischemic stroke in rural areas of Liaoning province. Methods: The study was a cross-sectional survey. From September 2017 to May 2018, a total of 10 926 rural residents aged ≥40 years were investigated in Chaoyang county, Lingyuan, Liaoyang county and Donggang city of Liaoning province. The investigation included questionnaire survey, physical examination and laboratory examination.Univariate and multivariate logistic regression models were used to analyze the risk factors of ischemic stroke. Results: The prevalence of ischemic stroke in the rural areas of Liaoning province was 5.51% (602/10 926), and the standardized prevalence rate was 4.04%. The standardized prevalence rate of male (5.05%) is higher than that of female (3.44%). The prevalence of ischemic stroke increased with age in both males (P<0.01) and females (P<0.01). Multivariate logistic regression analysis showed that age increase(compared with 40-49 years old group, 50-59 years old, OR=2.08, 95%CI 1.31-3.30, P=0.02; 60-69 years old, OR=3.90, 95%CI 2.51-6.05, P<0.01; 70-79 years old, OR=5.32, 95%CI 3.37-8.34, P<0.01; ≥80 years old, OR=3.64, 95%CI 2.00-6.62, P<0.01), male(OR=2.35, 95%CI 1.95-2.84, P<0.01),family history of stroke(OR=2.18, 95%CI 1.83-2.60, P<0.01),coronary heart disease (OR=2.01, 95%CI 1.52-2.66, P<0.01), hypertension (OR=2.82, 95%CI 2.21-3.60, P<0.01), diabetes mellitus (OR=1.36, 95%CI 1.11-1.67, P=0.03) and overweight/obese (OR=1.22, 95%CI 1.02-1.47, P=0.03) were the major risk factors of ischemic stroke. Conclusions: The prevalence of ischemic stroke in rural areas of Liaoning province is high. Age, male, family history of stroke, coronary heart disease, hypertension, diabetes mellitus, overweight/obesity are the risk factors of ischemic stroke in rural areas of Liaoning province.

[The correlation between left atrial sphericity and thromboembolic events in patients with atrial fibrillation]

Objective: To study the correlation between left atrial sphericity (LASP) and thromboembolic events (TE) in patients with atrial fibrillation (AF). Methods: This study was conducted in patients with AF underwent radiofrequency ablation in the Department of Cardiology of First Affiliated Hospital of Zhengzhou University from January 2011 to October 2018. The AF patients with TE (study group, n=157) and the AF patients without TE (control group, n=157) were matched for age and gender. The differences of LASP and other related indexes between the two groups were compared, and the correlation between LASP and TE was analyzed by conditional logistic regression. The receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic value of LASP for TE. Results: (1) The LASP in the study group was significantly higher than that in the control group [ (87.5±7.1) % vs. (82.8±6.1) %, P=0.001]. (2) Conditional logistic regression analyses showed that LASP (OR=1.10, 95%CI 1.05-1.16, P=0.001), left atrial volume index (OR=1.01, 95%CI 1.00-1.02, P=0.016) and CHA(2)D-VASc score (OR=1.77, 95%CI 1.30-2.41, P=0.001) were independently and positively correlated with TE. (3) The ROC curve analysis showed that the area under the curve (AUC) of left atrial sphericity (AUC=0.712, 95%CI 0.656-0.768, P=0.001) was larger than the AUC of either left atrial volume index (AUC=0.650, 95%CI 0.589-0.710, P=0.001) or CHA(2)D-VASc score (AUC=0.612, 95%CI 0.550-0.674, P=0.001). (4) CHA(2)D-VASc-LASP(2) score was positively correlated with TE (OR=1.95, 95%CI 1.55-2.42, P=0.001). Conclusion: LASP is independently and positively correlated with TE in patients with AF.

Human resource management in China (in the financial sector)

Systematically carried out over the past forty years economic reforms have given impetus to the development of the financial industry in China. Any changes suggest new approaches in the management system. Despite the results obtained there are some problems in the financial industry of China. In modern China there is a synthesis of Western and Eastern management theories, but it is necessary to pay tribute to traditional values, that influence on the thinking of leaders. The problems of human resource management in China in the financial industry have been considered in the article. The areas, where the most revolutionary changes are currently taking place, such as cross-border e-commerce, also have been indicated. In China, the proliferation of the Internet finance industry has been made possible by the surge in e-commerce. The fundamental factor in the psychology of the Chinese is Confucianism, on which they rely in all spheres of life. Despite the fact that in modern China there is a synthesis of the Western and Eastern theories of governance, it is necessary to pay tribute to the traditional values, which influence the thinking of the leaders of Chinese organizations. But new areas of activity require other, more advanced approaches to personnel training. The advantages and disadvantages of human resources management in the banking sector of China have been considered in the article. As a result of the analysis of indicators and problems of personnel management in the financial sphere, the main conclusions and recommendations on the structure of human resource management at this stage of improving society in China have been presented.

Therapeutic effect of transforaminal endoscopic spine system in the treatment of prolapse of lumbar intervertebral disc

OBJECTIVE

To investigate the clinical efficacy and safety of transforaminal endoscopic spine system (TESSYS) in treating the prolapse of lumbar intervertebral disc.

PATIENTS AND METHODS

462 patients with prolapse of lumbar intervertebral disc who were treated in our hospital from June 2012 to May 2016 were enrolled. All patients were randomly divided into 2 groups: the study group (n=231) and the control group (n=231). Patients in the study group received TESSYS, while those in the control group received conventional surgical treatment with posterior approach. Venous blood was collected before the surgery and 6 h, 12 h, 24 h, and 48 h after surgery. C reactive protein (CRP), interleukin-6 (IL-6), creatine phosphokinase (CPK) and white blood cell (WBC) in each patient were measured. The operation time, intraoperative blood loss, length of stay, postoperative ambulation time and complications were compared between the two groups. Clinical efficacy before and after surgery (1st day, 1st month, 3rd month, and 6th month after surgery) was evaluated according to visual analogue scale (VAS), Oswestry disability index (ODI) and modified MacNab criteria.

RESULTS

The operation time, intraoperative blood loss, length of stay, postoperative ambulation time and complications of patients in the study group were less than those of the control group (p<0.05). There were no significant differences in VAS score and ODI score on the 1st day before surgery, 1st day, 1st, 3rd, and 6th month after surgery (p>0.05). According to the improved MacNab standard, the excellent and good rate was 87.88% in the study group and 84.85% in the control group, the difference was not statistically significant (p>0.05). There were no significant differences in CRP, IL-6, CPK and WBC between the two groups before surgery (p>0.05). Postoperative levels of CRP, IL-6, CPK, and WBC in study group were better than those in control group, the differences were statistically significant (p<0.05).

CONCLUSIONS

TESSYS has the advantages of less bleeding, less traumatic reactions, fewer complications, rapid postoperative recovery, and exact short-term effect in treatment for prolapse of lumbar intervertebral disc.

Novel Models for Identification of the Ruptured Aneurysm in Patients with Subarachnoid Hemorrhage with Multiple Aneurysms

BACKGROUND AND PURPOSE

In patients with SAH with multiple intracranial aneurysms, often the hemorrhage pattern does not indicate the rupture source. Angiographic findings (intracranial aneurysm size and shape) could help but may not be reliable. Our purpose was to test whether existing parameters could identify the ruptured intracranial aneurysm in patients with multiple intracranial aneurysms and whether composite predictive models could improve the identification.

MATERIALS AND METHODS

We retrospectively collected angiographic and medical records of 93 patients with SAH with at least 2 intracranial aneurysms (total of 206 saccular intracranial aneurysms, 93 ruptured), in which the ruptured intracranial aneurysm was confirmed through surgery or definitive hemorrhage patterns. We calculated 13 morphologic and 10 hemodynamic parameters along with location and type (sidewall/bifurcation) and tested their ability to identify rupture in the 93 patients. To build predictive models, we randomly assigned 70 patients to training and 23 to holdout testing cohorts. Using a linear regression model with a customized cost function and 10-fold cross-validation, we trained 2 rupture identification models: RIM_C using all parameters and RIM_M excluding hemodynamics.

RESULTS

The 25 study parameters had vastly different positive predictive values (31%-87%) for identifying rupture, the highest being size ratio at 87%. RIM_C incorporated size ratio, undulation index, relative residence time, and type; RIM_M had only size ratio, undulation index, and type. During cross-validation, positive predictive values for size ratio, RIM_M, and RIM_C were 86% ± 4%, 90% ± 4%, and 93% ± 4%, respectively. In testing, size ratio and RIM_M had positive predictive values of 85%, while RIM_C had 92%.

CONCLUSIONS

Size ratio was the best individual factor for identifying the ruptured aneurysm; however, RIM_C, followed by RIM_M, outperformed existing parameters.

Janus particles: design, preparation, and biomedical applications

Janus particles with an anisotropic structure have emerged as a focus of intensive research due to their diverse composition and surface chemistry, which show excellent performance in various fields, especially in biomedical applications. In this review, we briefly introduce the structures, composition, and properties of Janus particles, followed by a summary of their biomedical applications. Then we review several design strategies including morphology, particle size, composition, and surface modification, that will affect the performance of Janus particles. Subsequently, we explore the synthetic methodologies of Janus particles, with an emphasis on the most prevalent synthetic method (surface nucleation and seeded growth). Following this, we highlight Janus particles in biomedical applications, especially in drug delivery, bio-imaging, and bio-sensing. Finally, we will consider the current challenges the materials face with perspectives in the future directions.

IL-37- and IL-35/IL-37-Producing Plasma Cells in Chronic Periodontitis

Periodontitis is one of the most prevalent chronic inflammatory diseases and is induced by the interaction between oral microorganisms and the host immune system. Plasma cells are of special interest in chronic periodontitis (CP), as they represent ~50% of infiltrated immune cells in periodontal lesions. Plasma cells constitute the only known cell type capable of antibody production; however, recent evidence supports an emerging role for distinct sets of plasma cells in cytokine production. However, the presence of cytokine-producing plasma cells in CP is unknown. In this study, we used immunohistochemistry to detect significantly elevated levels of IL-35 and IL-37 (2 recently identified anti-inflammatory cytokines) in CP gingival tissue as compared with healthy tissue. Remarkably, we demonstrate that CD138⁺ CD38⁺ plasma cells are the major immune cell type in CP gingival tissues and that these cells produce IL-35 and IL-37. We used immunofluorescence and confocal microscopy analysis to identify a subset of plasma cells with robust cytoplasmic expression of IL-37-we denote this subset as IL-37-producing plasma cells (CD138⁺CD38⁺P_IL-37). Another subset of plasma cells coproduces IL-35 and IL-37 and is denoted as IL-37/IL-35-coproducing plasma cells (CD138⁺CD38⁺P_IL-35/IL-37). We determined that these 2 plasma cell subsets are IgG⁺plasma cells. Moreover, we show that human recombinant IL-35 and IL-37 exhibit a dose-dependent inhibition of osteoclast formation in vitro (~78.9% and 97.7% inhibition in 300 ng/mL of IL-35 and IL-37, respectively, P < 0.05). Overall, our findings suggest that P_IL-37 and P_IL-35/IL-37 exist as subsets of plasma cells in CP lesions and that these 2 new types of plasma cells may regulate periodontitis pathogenesis by inhibiting alveolar bone loss through directly blocking osteoclast formation. Importantly, these data suggest a novel role of plasma cells and offer potential new mechanistic and regulatory targets to be investigated in the context of periodontal health and disease.

Dexmedetomidine attenuation of renal ischaemia-reperfusion injury requires sirtuin 3 activation

BACKGROUND

Dexmedetomidine attenuates renal ischaemia and reperfusion (I/R) injury, but its mechanism of action is unclear. As sirtuin 3 (SIRT3) activation can alleviate acute kidney injury, we investigated whether dexmedetomidine acts through SIRT3 to reduce renal I/R injury.

METHODS

The potential involvement of SIRT3 in dexmedetomidine attenuation of renal I/R injury was tested in HK2 cells subjected to hypoxia/reoxygenation and C57BL/6J mice subjected to renal I/R. A short interfering RNA targeting SIRT3 was used in some experiments to examine the potential role of SIRT3. Cell death and mitochondrial membrane potential (Δψm) were analysed in cultured cells. Mitochondrial damage in mice was assessed using electron microscopy and markers for renal function. Expression of cyclophilin D, cytochrome c, and SIRT3, and the level of cyclophilin D acetylation were determined.

RESULTS

Hypoxia/reoxygenation of HK2 cells increased cell death, cytochrome C expression, and cyclophilin D acetylation, and decreased Δψm and SIRT3 expression (P<0.05). Dexmedetomidine attenuated these changes. The dexmedetomidine effects were enhanced by SIRT3 overexpression and eliminated by SIRT3 knockdown. I/R in mice damaged renal function, and increased histological lesions, mitochondrial damage, cytochrome c expression, and cyclophilin D acetylation, while SIRT3 activity was decreased by 51% (P<0.05). Dexmedetomidine inhibited these changes in mice expressing normal levels of SIRT3, but not in SIRT3-knockdown mice.

CONCLUSIONS

Dexmedetomidine appears to act, at least in part, by up-regulating SIRT3 to inhibit mitochondrial damage and cell apoptosis and thereby protect against renal I/R injury.

Rapid Detection of Rongalite via a Sandwich Lateral Flow Strip Assay Using a Pair of Aptamers

A sandwich lateral flow strip assay (LFSA) using a couple of aptamers functionalized with gold nanoparticles (AuNPs) was designed to assess the presence of rongalite in agrifood products. More specifically, a biotin-labeled primary A09 aptamer immobilized on a streptavidin-coated membrane and a secondary B09 aptamer conjugated with AuNPs were developed as capturing and signaling probes, respectively. This system allows the successful and direct detection of rongalite in food samples with concentrations as low as 1 μg/mL, simply by observing the color change of LFSA control and test line.

Susceptibility of dairy cows to subacute ruminal acidosis is reflected in milk fatty acid proportions, with C18:1 trans-10 as primary and C15:0 and C18:1 trans-11 as secondary indicators

The current study was carried out to assess 2 hypotheses: (1) cows differ in susceptibility to a subacute ruminal acidosis (SARA) challenge, and (2) the milk fatty acid (FA) pattern can be used to differentiate susceptible from nonsusceptible cows. For this, 2 consecutive experiments were performed. During experiment 1, the milk FA pattern was determined on 125 cows fed an increasing amount of concentrate during the first 4 wk in milk (WIM). The coefficient of variation of several SARA indicative milk FA (i.e., C15:0, C18:1 trans-10, C18:2 cis-9,trans-11, and C18:1 trans-10 to C18:1 trans-11 ratio) increased, indicating that cows reacted differently upon the concentrate build-up. A first grouping was based on the milk fat C18:1 trans-10 proportion in the third WIM. Fifteen cows with the highest proportion of the latter FA (HT10) and their counterparts with low C18:1 trans-10 and equal parity distribution (LT10) were compared, which revealed that milk fat content and milk fat to protein ratio were lower for the HT10 group. From each of the HT10 and LT10 groups, 5 animals were selected for experiment 2. The subselection of the HT10 group, referred to as HT10s, showed a high proportion of C18:1 trans-10 at 3 WIM (>0.31 g/100 g of FA), a high level of C15:0 (on average ≥1.18 g/100 g of FA over the 4 WIM), and a sharp decrease of C18:1 trans-11 (Δ ≥ 0.25 g/100 g of FA during the 4 WIM). Their counterparts (LT10s) had a low milk fat C18:1 trans-10 proportion at 3 WIM (<0.23 g/100 g of FA), an average C15:0 proportion of 0.99 g/100 g of FA or lower, and a rather stable C18:1 trans-11 proportion. The HT10s group was hypothesized to be more susceptible to a SARA challenge, achieved by increasing amounts of rapidly fermentable carbohydrates in experiment 2. The HT10s cows had a lower nadir, mean, and maximum reticulo-ruminal pH; longer period of reticulo-ruminal pH below 6.0; and higher daily reticulo-ruminal pH variation compared with LT10s cows. Throughout experiment 2, HT10s and LT10s cows differed in levels of SARA indicative milk FA. Five animals, including one LT10s and 4 HT10s cows, experienced SARA, defined as reticulo-ruminal pH <6.0 for more than 360 min/d. These results indicate that it is possible to distinguish cows with different susceptibility to a SARA challenge within a herd by monitoring the milk FA composition when cows receive the same diet.

Combining the randomized response technique and the network scale-up method to estimate the female sex worker population size: an exploratory study

OBJECTIVES

Recall bias, barrier effects, transmission error, and response bias affecting the network scale-up method (NSUM) led the Joint United Nations Programme on HIV/AIDS and the World Health Organization to designate NSUM as a developing method for estimating the size of high-risk populations in 2010. The method has subsequently been adjusted for three of these biases. The present study, therefore, aimed to explore the combination of the randomized response technique (RRT) and NSUM to adjust the last remaining bias.

STUDY DESIGN

RRT was used in an NSUM survey to estimate the population proportion of female sex workers (FSWs) in Taiyuan, China, in 2012.

METHODS

Multiplier method estimates and national-level estimates of the population proportion of FSWs were used as criteria to assess the aforementioned results.

RESULTS

Successful interviews were completed with 96.4% of the respondents selected for the NSUM survey. The NSUM estimate fell within the range of the national-level estimates of the population proportion of FSWs in Asia and was close to the estimate yielded by the multiplier method.

CONCLUSIONS

In the present study, the combination of RRT and NSUM obtained a high response rate and produced a reliable estimate of the size of a high-risk population.

[Transcystic biliary drainage versus nasobiliary drainage during primary closure of the laparoscopic choledochotomy]

Objective: To compare the clinical efficacy of transcystic biliary drainage with nasobiliary drainage during primary closure following laparoscopic choledochotomy. Methods: The clinical data of 106 patients with cholecystolithiasis and choledocholithiasis treated by laparoscopy at Department of General Surgery, Danyang People's Hospital from May 2014 to June 2017 were analyzed prospectively. The patients were divided into 2 groups by means of random number method: the study group was treated with transcystic biliary drainage, and the control group adopted nasobiliary drainage. The operation time, postoperative drainage volume, postoperative hospital stay and postoperative complications were compared between the 2 groups. Results: All patients in the two groups completed the operation successfully. Compared with nasobiliary drainage, the operation time of transcystic biliary drainage was shortened ((133.9±14.7) minutes vs. (143.3±21.7) minutes, t=-2.617, P<0.05). Postoperative hospital stay ((8.2±1.7) days vs. (7.7±2.5) days), the difference between the two groups was not statistically significant(P>0.05). The quantity of bile drainage was no significant difference in the two groups of patients. There were 1 case of duct obstruction and 2 cases of catheter slippage during transcystic biliary drainage, without causing bile leakage. During nasobiliary drainage, there were 3 cases of catheter obstruction, 1 case of catheter slippage, 2 cases of self extubation, 1 case of bile peritonitis caused by catheter blockage, transferred to laparotomy and T tube drainage. The patients were followed up for 1 month to 17 months, with an average of 8 months. B-ultrasound showed no bile duct stenosis and hepatic function was normal. Conclusions: Transcystic biliary drainage could achieve the same biliary drainage as well as nasobiliary drainage during primary closure following laparoscopic choledochotomy. In addition, transcystic biliary drainage maintain the physiological function of bile duct, it is simple and minimally invasive under certain conditions.

Characterization of a Potential Ripening Regulator, SlNAC3, from Solanum Lycopersicum

NAC (for NAM, ATAF1-2, and CUC2) proteins are one of the largest transcription factor families in plants. They have various functions and are closely related to developmental processes of fruits. Tomato (Solanum lycopersicum) is a model plant for studies of fruit growth patterns. In this study, the functional characteristics and action mechanisms of a new NAC-type transcription factor, SlNAC3 (SGN-U568609), were examined to determine its role in tomato development and ripening. The SlNAC3 protein was produced by prokaryotic expression and used to immunize New Zealand white rabbits to obtain a specific polyclonal antibody against SlNAC3. By co-immunoprecipitation and MALDI-TOF-MS assays, we showed that there was an interaction between the SlNAC3 protein and Polygalacturonase-2 (PG-2), which is related to the ripening and softening of fruit. Chromatin immunoprecipitation assays revealed the genome of the highly stress-tolerant Solanum pennellii chromosome 10 (sequence ID, HG975449.1), further demonstrating that SlNAC3 is a negative regulator of drought and salinity stress resistance in tomato, consistent with previous reports. These results indicate that SlNAC3 is not only involved in abiotic stress, but also plays a necessary role in mediating tomato ripening.

Urinary kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin as early biomarkers for predicting vancomycin-associated acute kidney injury: a prospective study

OBJECTIVE

Previous studies have demonstrated that urinary kidney injury molecule-1 (uKIM-1) and neutrophil gelatinase-associated lipocalin (uNGAL) were superior to serum creatinine (Scr) in detecting acute kidney injury (AKI), but their ability to predict clinical vancomycin-associated AKI has not been investigated. This study aimed to investigate the abilities of uKIM-1 and uNGAL individually and in combination to predict vancomycin-associated AKI.

PATIENTS AND METHODS

Scr, uKIM-1, and uNGAL were measured on the day before and days 1, 2, and 3 of vancomycin therapy in a generalized adult population. Levels of these biomarkers between AKI and non-AKI groups were comparatively analyzed. Predictive performances were evaluated by receiver operating characteristic curve (ROC) analysis.

RESULTS

A total of 87 patients were enrolled, and among them, 11 (12.6%) patients developed AKI. Urinary KIM-1 and NGAL levels in the AKI group were higher than in the non-AKI group at all time points (p < 0.05), and the areas under the receiver operating characteristic curves (AUC) were 0.849 (95% confidence interval [CI] 0.750-0.948) for uKIM-1 and 0.824 (95% CI 0.726-0.922) for uNGAL, with cut-off values of 1.72 ng/mL and 9.07 ng/mL respectively. The AUC of uKIM-1 and uNGAL combined was 0.852 (95% CI 0.754-0.949), and the sensitivity and specificity were 90.9% and 75.0%, respectively.

CONCLUSIONS

Urinary KIM-1 and NGAL could efficiently discriminate patients with or without vancomycin-associated AKI earlier than Scr, and the combined urinary biomarkers showed fair discrimination compared with the individual biomarkers.

Micromechanical Origin of Particle Size Segregation

We computationally study the micromechanics of shear-induced size segregation and propose distinct migration mechanisms for individual large and small particles. While small particles percolate through voids without enduring contacts, large particles climb under shear through their crowded neighborhoods with anisotropic contact network. Particle rotation associated with shear is necessary for the upward migration of large particles. Segregation of large particles can be suppressed with inadequate friction, or with no rotation; increasing interparticle friction promotes the migration of large particles, but has little effect on the percolation of small particles.

One-pot preparation of polylactic acid-ibuprofen conjugates and their performance characterization

Merging esterification modification, carrier preparation, and chemical conjugation into a one-pot reaction as a new strategy for developing the polylactic acid-ibuprofen conjugates is described.

A “hairy” polymer/3D-foam hybrid for flexible high performance thermal gap filling applications in harsh environments

A new polymer/3D-foam-composite is presented for filling large gaps with high conformity and thermal conductivity, while rendering strong mechanical support.

Characterization of base roughness for granular chute flows

Base roughness plays an important role in the dynamics of granular flows but is still poorly understood due to the difficulty of its quantification. For a bumpy base made of spheres, at least two factors should be considered in order to characterize its geometric roughness, namely, the size ratio of flow to base particles and the packing arrangement of base particles. In this paper, we propose an alternative definition of base roughness, R_{a}, as a function of both the size ratio and the distribution of base particles. This definition is generalized for random and regular packings of multilayered spheres. The range of possible values of R_{a} is presented, and optimal arrangements for maximizing base roughness are studied. Our definition is applied to granular chute flows in both two- and three-dimensional configurations, and is shown to successfully predict whether slip occurs at the base. A transition is observed from slip to nonslip conditions as R_{a} increases. Critical values of R_{a} are identified for the construction of a nonslip base at various angles of inclination.