Effect of rare-earth oxide (Eu2O3) on the physical, mechanical, acoustic and radiation shielding properties of the CaO-Gd2O3-SiO2-B2O3 glasses

In this study, we examined the effectiveness of europium-doped calcium gadolinium silicoborate glasses for determining their physical, mechanical, acoustic and radiation shielding properties with compositions of 25Gd2O3-10CaO-10SiO2-xEu2O3 -(55-x) B2O3 (where, x is 0.1, 0.2, 0.3, and 0.4 mol%). These glasses were theoretically analyzed using the Geant4 toolkit and Phy-X PSD software to calculate their performance for x-ray energies ranging from 0.2 to 1.2 MeV. The physical, acoustic and mechanical properties were determined using the Makishima-Mackenzie (MM) model. As the content of Eu2O3 increases, the density of the glasses also increases. As the amount of Eu2O3 increases, the mechanical properties decrease. This means that certain mechanical properties of the material may be negatively affected, resulting in a decreased ability to maintain structural integrity and resist deformation when exposed to radiation. The elastic modulus reflects the material's stiffness or rigidity, and a lower value indicates that the material is more prone to deformation when subjected to mechanical stress. Bulk and Young's moduli show a decreasing trend from 255.49 to 253.10 GPa and 368.20 to 366.50 GPa with increasing Eu+3 concentration in the glass samples. The LAC values of EuGd4 glass is much smaller when compared to the other glasses. The presence of gadolinium and europium compounds in the glass increases its ability to absorb radiation due to the elements of high atomic numbers. This is because the higher effective atomic number (Zeff) of these compounds enhances the glass of shielding capabilities against neutron and gamma rays, resulting in improved radiation protection.

Metronidazole degradation mechanism by sono-photo-Fenton processes using a spinel ferrite cobalt on activated carbon catalyst

A heterogeneous catalyst was prepared by anchoring spinel cobalt ferrite nanoparticles on porous activated carbon (SCF@AC). The catalyst was tested to activate hydrogen peroxide (HP) in the Fenton degradation of metronidazole (MTZ). SCF nanoparticles were produced through the co-precipitation of iron and cobalt metal salts in an alkaline condition. Elemental mapping, physico-chemical, morphological, structural, and magnetic properties of the as-fabricated catalyst were analyzed utilizing EDX mapping, FESEM-EDS, TEM, BET, XRD, EDS, and VSM techniques. The porous structure of AC enhanced the catalytic activity of SCF by a significant decrease in the agglomeration of SCF nanoparticles. The effectiveness of SCF@AC in Fenton degradation improved substantially when UV light and ultrasound (US) irradiations was induced, most likely due to the strong synergistic effect between the catalyst and these irradiation sources. The photo-Fenton system was more efficient than the Fenton, sono-, and sono-photo-Fenton processes eliminating both MTZ and TOC. It was found that AC not only dispersed SCF nanoparticles and improved the stability of the catalyst, but also provided a high adsorption capacity of MTZ, resulting in a faster degradation. After 60 min of the photo-Fenton reaction, the elimination efficiencies of MTZ (30 mg L-1) and TOC were 97 and 42.1% under optimum operational conditions (pH=3.0, HP=4.0 mM, SCF@AC=0.3 g L-1, and UV=6 W). SCF@AC showed excellent stability with low leaching of metal ions during reaction. Radical and non-radical (O2•-, OH•, and 1O2 species), alongside adsorption and photocatalysis mechanisms, were responsible for MTZ decontamination over the SCF@AC/HP/UV system. A comprehensive study on the HP activation mechanism and MTZ degradation pathway was obtained through scavenging tests. The findings demonstrate that SCF@AC is an effective, reusable, and environmentally sustainable catalyst for advanced oxidation processes that can effectively remove organic pollutants from wastewater. This study offers valuable insights into the feasibility of employing SCF@AC catalysts in Fenton-based processes for the degradation of MTZ.

The epidemiology of neck and low back pain in Iran: a national and sub-national analysis from 1990 to 2019

Background

Neck pain (NP) is a condition influenced by multiple factors. It places a significant burden on individuals suffering from NP and on social and economic systems. On a global scale, low back pain (LBP) stands out as a significant contributor to years lost to disability, and this burden is on the rise due to population growth and aging.

Methods

The Global Burden of Disease database was used to collect data on the prevalence, incidence, and years lived with disability (YLD) of NP and LBP between 1990 and 2019. Various factors, including age group, gender, Iran, and its 31 provinces, were used to classify the data.

Results

Iran accounted for 0.86 million incident cases of NP in 2019, with age-standardized incident rate per 100 000 population of 934.1. Tehran has the maximum age-standardized prevalence, incidence, and YLD. Iran accounted for the age-standardized incidence rate for LBP per 100 000 population of 3492.9, and it reduced to -8.35% from 1990. Mazandaran exhibits the highest levels of prevalence, incidence, and YLD for LBP in 2019. In Iran, the point prevalence of NP in 2019 was higher in females and increased with age up to 50-54 years for females and 70-74 years for males. However, there is only a slight difference between females and males in Iran regarding LBP prevalence.

Conclusions

In this study, the authors report the prevalence, incidence, YLD, and age-standardized rates for NP and LBP in the world's general population and Iran's population based on its sub-nations in 1990 and 2019.

Enrichment of set yoghurt with flaxseed oil, flaxseed mucilage and free or encapsulated Lacticaseibacillus casei: Effect on probiotic survival and yoghurt quality attributes

This study was intended to develop yoghurt products incorporated with flaxseed mucilage (FM), flaxseed oil (FO) and free or encapsulated Lacticaseibacillus casei probiotics. FM (0.9%) and sodium alginate (2%) were used as wall materials for encapsulating L. casei. Different physicochemical and sensory properties of the yoghurt, as well as the L. casei survival, were determined during 21 days of storage at 4 °C. Based on the results, FM showed a stimulatory effect on the growth of probiotics and thus, significantly decreased the Log reduction of the probiotics during storage (P < 0.05). Moreover, encapsulating probiotics significantly decreased the Log reduction during storage in comparison with the free bacteria (P < 0.05). Incorporating FM and free probiotics significantly increased the acidity and decreased the pH of the samples; while encapsulating L. casei successfully prevented the acidity increment in probiotic fortified yoghurt products (P < 0.05). The addition of FM significantly improved the water holding capacity of the yoghurt (P < 0.05). Incorporating either free L. casei, FO or FM significantly reduced the flavor and overall acceptance scores; while, the addition of L. casei in the encapsulated form did not significantly alter the overall acceptance scores of the yoghurt samples (P < 0.05).

Burden of ischemic heart disease in the Middle East and North Africa (MENA) and attributable risk factors: An epidemiological analysis from 1990 to 2019

Introduction

Despite the burden of ischemic heart disease (IHD), there remains a paucity of research on the incidence, mortality, and burden of this condition in the Middle East and North Africa (MENA) regions. This study aimed to evaluate the epidemiology and the risk factors associated with IHD in the MENA region.

Methods

This study was performed based on the GBD study 2019 data. We retrieved the data related to the epidemiology and burden of IHD, including prevalence, incidence, years of life lost due to premature death (YLLs), years lived with disability (YLDs), and mortality at the global level and in MENA countries across years and sexes.

Results

IHD accounted for approximately 2.55 million (95 % UI 2.29-2.83) incident cases in MENA in 2019, with an age-standardized incidence rate of 613.87 (95 % UI 555.84-675.16) per 100 000 people, which has decreased by 9 % between 1990 and 2019. IHD accounted for 11.01 % of DALYs causes in MENA in 2019, an increase of 68 % compared to 1990. The DALYs rate from IHD increased with age in both men and women and was higher in men than in women in all age groups, except 85-89 years age-group, in 2019.

Conclusion

The age-standardized prevalence and incidence of IHD are decreasing in MENA. However, this reduction is lower than the global level, which can be due to a weaker performance of the countries in the region in reducing the prevalence and incidence of the disease compared to the global average.

Ginger intervention on body weight and body composition in adults: a GRADE-assessed systematic review and dose-response meta-analysis of 27 randomized controlled trials

CONTEXT

Ginger consumption may have an inverse relationship with obesity and metabolic syndrome parameters; however, clinical trials have reported contradictory results.

OBJECTIVE

To systematically review and analyze randomized controlled trials (RCTs) assessing the effects of ginger on body weight and body composition parameters.

METHODS

Databases were searched for appropriate articles up to August 20, 2022. All selected RCTs investigated the impact of ginger on glycemic indices in adults. A random effects model was used to conduct a meta-analysis, and heterogeneity was assessed using the I2 statistic. Net changes in body weight, body mass index (BMI), waist circumference (WC), and percent body fat were used to calculate the effect size, which was reported as a weighted mean difference (WMD) and 95% confidence intervals (CIs). The risk of bias was assessed.

RESULTS

A total of 27 RCTs involving 1309 participants were included. The certainty in the evidence was very low for WC and BMI, and low for body weight and percent body fat as assessed by the GRADE evidence profiles. The meta-analysis showed a significant association between ginger supplementation and a reduction in body weight (WMD, -1.52 kg; 95%CI, -2.37, -0.66; P < 0.001), BMI (WMD, -0.58 kg/m2; 95%CI, -0.87, -0.30; P < 0.001), WC (WMD, -1.04 cm; 95%CI: -1.93, -0.15; P = 0.021), and percent body fat consumption (WMD, -0.87%; 95%CI, -1.71, -0.03; P = 0.042). The results of the nonlinear dose-response analysis showed a significant association between the ginger dose with body weight (Pnonlinearity = 0.019) and WC (Pnonlinearity = 0.042). The effective dose of ginger intervention for body mass reduction was determined to be 2 g/d in dose-response analysis. The duration of ginger intervention had a significant nonlinear relationship with body weight (Pnonlinearity = 0.028) with an effective duration of longer than 8 weeks.

CONCLUSIONS

Our findings provide evidence that ginger consumption may significantly affect body composition parameters nonlinearly. More, well-constructed RCTs are needed.

Effects of flaxseed supplementation on weight loss, lipid profiles, glucose, and high-sensitivity C-reactive protein in patients with coronary artery disease: A systematic review and meta-analysis of randomized controlled trials

This meta-analysis aimed to evaluate the effects of flaxseed supplementation on weight loss, lipid profiles, high-sensitivity C-reactive protein (hs-CRP), and glucose levels in patients with coronary artery disease (CAD). A systematic search was performed using various online databases, including Scopus, PubMed, Web of Science, EMBASE, and Cochrane Library, to identify relevant randomized controlled trials (RCTs) until June 2023. To evaluate heterogeneity among the selected studies, the Q-test and I2 statistics were employed. Data were combined using either a fixed- or random-effects model and presented as a weighted mean difference (WMD) with a 95% confidence interval (CI). Of the 428 citations, six RCTs were included. The pooled results did not show significant changes in the WMD of lipid factors (high-density lipoprotein cholesterol, triglycerides (TG), low-density lipoprotein cholesterol, and total cholesterol) following flaxseed intake. However, after performing a sensitivity analysis to determine the source of heterogeneity, flaxseed supplementation resulted in a significant decrease in TG levels (WMD = -18.39 mg/dL; 95% CI: -35.02, -1.75). Moreover, no significant differences were observed in either weight or BMI following flaxseed intake. However, the circulating levels of fasting blood glucose (WMD = -8.35 mg/dL; 95% CI: -15.01, -1.69, p = .01) and hs-CRP (WMD = -1.35 mg/L; 95% CI: -1.93, -0.77, p < .01) significantly decreased after the intervention. Flaxseed supplementation was associated with lowering FBS, hs-CRP, and TG levels but did not affect weight loss parameters and other lipid markers in CAD.

Comparison of Anaheal Plus and Ibuprofen's Analgesic Effect after Root Canal Treatment in Patients Referred to Amol Private Clinic: a Clinical Trial Study

Background and purpose: Since pain control in dental treatments, including root canal treatment, is challenging, and no study has measured the appropriate pattern of Anaheal Plus drug consumption in reducing pain after root canal treatment, in this study the appropriate pattern of taking Anaheal Plus drug in reducing pain after root canal treatment was evaluated. Material and methods:The present study examined maxillary and mandibular molar teeth with irreversible pulpitis. Patients were divided into three groups: A) Anaheal Plus capsule; B) control; and C) ibuprofen. Teeth were treated in two sessions, pulpectomy treatment was performed and drugs were used between sessions. A visual analog scale questionnaire was used to assess pain. Patients were asked to record the pain score before the root canal treatment as well as eight hours, 48 hours and five days after root canal treatment. All procedures were done in Amol's private clinic, where root canal treatment was administered by a dentist, and the teeth were obturated after a week. Findings: This study examined 90 patients with an average age of 33.94 years. Rescue doses were reported only in the control group, and there was a significant difference between groups (p-value < 0.001). In all groups, pain had decreased significantly (p-value<0.001), but the average pain in groups A and C was lower than that of group B at all times, and there was no difference between them. Conclusion:Anaheal Plus significantly reduced pain after root canal treatment compared to the control group.

Liver fibrosis in pars cohort study: A large-scale study on the prevalence and correlated factors

BACKGROUNDS AND STUDY AIMS

The fibrosis-4 (FIB-4) is a non-invasive scoring system for estimating liver fibrosis severity as a biomarker of chronic liver disease. We aimed to estimate the prevalence and severity of chronic liver disease at the community level using FIB-4.

PATIENTS AND METHODS

This cross-sectional study was conducted using the Pars Cohort database collected in Valashar, Fars province, Iran. Participants were divided into three groups based on their FIB-4 scores: low risk of liver fibrosis (FIB < 1.45), intermediate cases (1.45 ≤ FIB-4 ≤ 3.25), and high risk of liver fibrosis (FIB-4 > 3.25).

RESULTS

In total, 9269 individuals with a mean age of 52.65 years were enrolled in the study, of which 4278 (46.2 %) were male. Among all participants, 7853 (84.7 %) were in the low-risk, and 65 (0.7 %) were in the high-risk groups. In the final ordinal regression model, male gender, being a farmer or rancher, living in rural areas, history of opioid use, history of jaundice, no history of diabetes, history of depression, and positive HBs Ag were independently associated with higher FIB-4 scores.

CONCLUSION

Our study revealed that males, individuals residing in rural areas, and those engaged in farming and ranching occupations face a heightened risk of liver fibrosis. These findings emphasize the need for future programs for early detection and effective management of liver fibrosis in these at-risk populations.

Investigating the effect of type of fish and different cooking methods on the residual amount of polycyclic aromatic hydrocarbons (PAHs) in some Iranian fish: A health risk assessment

The aim of this study was to assess the level of PAHs and associated health risks in different types of fish cooked with different methods, using the MSPE-GC/MS technique (magnetic solid phase extraction with gas chromatography/mass spectrometry). The limits of detection (LODs), limits of quantification (LOQs) and recovery percentages ranged from 0.1 to 0.63 μg/kg, 0.3-1.89 μg/kg, and 93.7 to 102.6%, respectively. The results showed that the mean of ƩPAHs in all samples was 20.31 ± 6.60 µg/kg. Additionally, PAH4 and BaP levels in all samples were 4.58 ± 1.40 and 1.08 ± 0.36 µg/kg, respectively, which were below the European Union (EU) standard level (12 and 2 µg/kg, respectively). The results showed that among 5 types of fish, starry sturgeon had highest average total PAHs (13.24 ± 1.84 µg/kg), while Caspian Sea sprat had the lowest average total PAHs (1.24 ± 0.8 µg/kg). In terms of cooking methods (charcoal-grilled fish, fried fish and oven-grilled fish), charcoal-grilled fish had the highest average total PAH level at 25.41 ± 7.31 µg/kg, while the lowest average total PAH was found in the raw fish sample at 16.44 ± 4.63 µg/kg. The Monte Carlo Simulation was used to determine the 95% ILCRs (Incremental Lifetime Cancer Risk) due to ingestion of fish. The results showed that the ILCR for adults was 2.85E-9, while for children it was 1.32E-8. Therefore, based on these findings, it can be concluded that the consumption of fish cooked with different methods does not pose a risk to human health in terms of the amount of PAHs (ILCR < 1 × 10-4).

Comprehensive study of moiré deflectometry based on diffraction order filtering of fringes

This paper presents a detailed investigation of the theory of moiré deflectometry through a comprehensive analysis of the higher-order diffraction of moiré fringes. We demonstrate the possibility of achieving always-high-resolution moiré fringes regardless of Ronchi grating positions and Talbot distance by filtering out the even diffraction orders of moiré fringes. Our theoretical studies lead to a comprehensive formulation of this technique, revealing the high potential of moiré deflectometry towards more precise measurement.

High yield expression and purification of Aspergillus flavus uricase cloned in Pichia pink™ expression system

In this research, for the first time, A. flavus uricase gene was cloned in pPink-UOX plasmid under strong alcohol oxidase promoter of Pichia pink expression system after codon optimization. After selecting the best uricase producing clone with an activity of 0.7 U/ml at the Flask level, a 5-L fermenter was used to increase the expression of the enzyme. Within 60 h, the fermentation process produced 1500 g of biomass from 4 L of semi defined culture media and expressed 2.5 g/L of the enzyme. The purity of recombinant uricase production using three consecutive DEAE Sepharose, CM Sepharose and Phenyl Sepharose columns was above 99%, which was confirmed by SDS-PAGE and RP-HPLC analyses. Size exclusion chromatography analysis showed that the purified enzyme has comparable heterogeneity to the Rasburicase. The yield of recombinant uricase production in this study was 63% and its specific activity was 24 U/mg. The high expression of recombinant uricase in the Pichia pink strain and the increased enzyme activity compared to the standard sample indicate the potential of therapeutic and diagnostic applications of recombinant uricase in the present study.

Barriers and enablers of vigorous intermittent lifestyle physical activity (VILPA) in physically inactive adults: a focus group study

BACKGROUND

Vigorous Intermittent Lifestyle Physical Activity (VILPA) refers to brief bouts of vigorous intensity physical activity performed as part of daily living. VILPA has been proposed as a novel concept to expand physical activity options among the least active. As a nascent area of research, factors which impede or encourage VILPA in physically inactive adults are yet to be explored. Such information is pertinent in the design of future interventions. We examined the barriers and enablers of VILPA among physically inactive adults using the Capability, Opportunity, Motivation, Behavior (COM-B) model as a conceptual framework.

METHODS

We recruited a sample of self-identified physically inactive middle-aged and older adults (N = 78) based in Australia to take part in 19 online focus groups across three age groups: young-middle (age 35-44), middle (age 45-59) and old (age 60-76). We analyzed interviews using a critical realist approach to thematic analysis. Identified barriers and enablers were subsequently mapped onto the COM-B model components.

RESULTS

The data generated 6 barriers and 10 enablers of VILPA that corresponded to COM-B concepts. Barriers included physical limitations (physical capability), perceptions of aging, need for knowledge (psychological capability), environmental constraints (physical opportunity), perceptions of effort and energy, and fear (automatic motivation). Enablers included convenience, reframing physical activity as purposeful movement, use of prompts and reminders (physical opportunity), normalization of taking the active option, gamification (social opportunity), sense of achievement, health improvements, personally salient rewards (reflective motivation), identity fit, and changing from effortful deliberation to habitual action (automatic motivation).

CONCLUSION

The barriers and enablers of VILPA span capability, opportunity, and motivation beliefs. Promoting the time-efficient nature and simplicity of VILPA requiring no equipment or special gym sessions, the use of prompts and reminders at opportune times, and habit formation strategies could capitalize on the enablers. Addressing the suitability of the small bouts, the development of specific guidelines, addressing safety concerns, and explicating the potential benefits of, and opportunities to do, VILPA could ameliorate some of the barriers identified. Future VILPA interventions may require limited age customization, speaking to the potential for such interventions to be delivered at scale.

Spinel cobalt ferrite-based porous activated carbon in conjunction with UV light irradiation for boosting peroxymonosulfate oxidation of bisphenol A

Developing heterogeneous catalysts with high performance for peroxymonosulfate (PMS) activation to decontaminate organic pollutants from wastewater is of prominent importance. In this study, spinel cobalt ferrite (CoFe₂O₄) materials were coated on the surface of powdered activated carbon (CoFe₂O₄@PAC) via the facile co-precipitation method. The high specific surface area of PAC was beneficial for the adsorption of both bisphenol A (BP-A) and PMS molecules. The CoFe₂O₄@PAC-mediated PMS activation process under UV light could effectively eliminate 99.4% of the BP-A within 60 min of reaction. A significant synergy effect was attained between CoFe₂O₄ and PAC towards PMS activation and subsequent elimination of BP-A. Comparative tests demonstrated that the heterogeneous CoFe₂O₄@PAC catalyst had a better degradation performance in comparison with its components and homogeneous catalysts (Fe, Co, and, Fe + Co ions). The formed by-products and intermediates during BP-A decontamination were evaluated using LC/MS analysis, and then a possible degradation pathway was proposed. Moreover, the prepared catalyst exhibited excellent performance in recyclability with slight leaching amounts of Co and Fe ions. A TOC conversion of 38% was obtained after five consecutive reaction cycles. It can be concluded that the PMS photo-activation process via the CoFe₂O₄@PAC catalyst can be utilized as an effective and promising method for the degradation of organic contaminants from polluted-water resources.

In vitro anti-Toxoplasma gondii activity of Ganoderma lucidum extracts

OBJECTIVE

Ganoderma extracts have the potential to be used as anti-cancer, anti-inflammatory, immunomodulator, and antimicrobial agents, as evaluated in numerous studies. This study was aimed to determine the lethal and inhibitory effects of aqueous, hydroalcoholic, and alcoholic extracts of Ganoderma lucidum on Toxoplasma gondii RH strain tachyzoites, in vitro.

RESULTS

All three types of extracts showed toxoplasmacidal effects. The highest percentage of mortality was related to hydroalcoholic extract. The EC50 of Ganoderma extracts for tachyzoites were 76.32, 3.274, and 40.18 for aqueous, hydroalcoholic and alcoholic extracts, respectively. The selectivity index obtained for hydroalcoholic extract was 71.22, showing the highest activity compared to other extracts. According to our findings, the hydroalcoholic part was the most effective substance among the extracts. This basic study showed obvious anti-toxoplasma effect of Ganoderma lucidum extracts. These extracts can be used as candidates for further in-depth and comprehensive studies especially In vivo experiments to prevent toxoplasmosis.

Effect of voluntary wheel running on autophagy status in lung tissue of high-fat diet-fed rats

Here, we aimed to explore the therapeutic effect of voluntary wheel running (VWR) in high-fat diet-fed rats on pulmonary tissue injury via the modulation of autophagic response. Thirty-two rats were allocated into four groups; normal diet (Control); VWR; high-fat-diet (HFD), and HFD + VWR. After three months, pathological effect of HFD on pulmonary tissue was investigated. The levels of tumour necrosis factor (TNF)-α were detected in the bronchoalveolar lavage fluid (BALF). We monitored the expression of interleukin (IL)-6 and autophagy-related genes in lung tissues. H&E staining showed pathological changes in HFD group coincided with the increase of TNF-α levels in the bronchoalveolar fluid compared to the normal rats. Our results showed the up-regulation of IL-6, becline-1, LC3 and P62 in the HFD group compared to the Control group. VWR inhibited HFD-induced changes and could decrease HFD-induced changes via the regulation of autophagy status.

Innovative Diagnostic Peptide-Based Technologies for Cancer Diagnosis: Focus on EGFR-Targeting Peptides

Active targeting using biological ligands has emerged as a novel strategy for the targeted delivery of diagnostic agents to tumor cells. Conjugating functional targeting moieties with diagnostic probes can increase their accumulation in tumor cells and tissues, enhancing signal detection and, thus, the sensitivity of diagnosis. Due to their small size, ease of chemical synthesis and site-specific modification, high tissue penetration, low immunogenicity, rapid blood clearance, low cost, and biosafety, peptides offer several advantages over antibodies and proteins in diagnostic applications. Epidermal growth factor receptor (EGFR) is one of the most promising cancer biomarkers for actively targeting diagnostic and therapeutic agents to tumor cells due to its active involvement and overexpression in various cancers. Several peptides for EGFR-targeting have been identified in the last decades, which have been obtained by multiple means including derivation from natural proteins, phage display screening, positional scanning synthetic combinatorial library, and in silico screening. Many studies have used these peptides as a targeting moiety for diagnosing different cancers in vitro, in vivo, and in clinical trials. This review summarizes the progress of EGFR-targeting peptide-based assays in the molecular diagnosis of cancer.

A Comparison of Weighted Stochastic Simulation Methods for the Analysis of Genetic Circuits

Rare events are of particular interest in synthetic biology because rare biochemical events may be catastrophic to a biological system by, for example, triggering irreversible events such as off-target drug delivery. To estimate the probability of rare events efficiently, several weighted stochastic simulation methods have been developed. Under optimal parameters and model conditions, these methods can greatly improve simulation efficiency in comparison to traditional stochastic simulation. Unfortunately, the optimal parameters and conditions cannot be deduced a priori. This paper presents a critical survey of weighted stochastic simulation methods. It shows that the methods considered here cannot consistently, efficiently, and exactly accomplish the task of rare event simulation without resorting to a computationally expensive calibration procedure, which undermines their overall efficiency. The results suggest that further development is needed before these methods can be deployed for general use in biological simulations.

Anchoring ZnO on spinel cobalt ferrite for highly synergic sono-photo-catalytic, surfactant-assisted PAH degradation from soil washing solutions

In this study, the photocatalytic activity of ZnO was effectively improved via its combination with spinel cobalt ferrite (SCF) nanoparticles. The catalytic performance of ZnO@SCF (ZSCF) was investigated in coupling with UV irradiation and ultrasound (US), as a heterogeneous sono-photocatalytic process, for the decontamination of phenanthrene (PHE) from contaminated soil. Soil washing tests were conducted in a batch environment, after extraction assisted by using Tween 80. Several characterization techniques such as XRD, FESEM-EDS, BET, TEM, UV-vis DRS, PL and VSM were utilized to determine the features of the as-prepared catalysts. ZSCF showed an excellent catalytic activity toward degradation of PHE in the presence of US and UV with a significant synergic effect. It was found that more than 93% of PHE (35 mg/L) and 87.5% of TOC could be eliminated by the integrated ZSCF/US/UV system under optimum operational conditions (pH: 8.0, ZSCF: 1.5 g/L, UV power: 6.0 W and US power: 70 W) within 90 min of reaction. After five times of use, ZSCF illustrated good reusability in the decontamination of PHE (87%) and TOC (79%). Quenching tests revealed the contribution of h⁺, HO^• and e^- species during PHE degradation over ZSCF/UV/US and an S-scheme photocatalytic mechanisms was proposed for the possible charge transfer routes under the ZSCF system. This study provides the important role of SCF in enhancing the ZnO photocatalytic activity due to its high performance, easy recovery and excellent durability, which it make an efficient and promising catalyst in environmental clean-up applications.

Effect of multifactorial free and liposome-coated of bay laurel (Laurus nobilis) and rosemary (Salvia rosmarinus) extracts on the behavior of Listeria monocytogenes and Vibrio parahaemolyticus in silver carp (Hypophthalmichthys molitrix) stored at 4 °C

In this study, the effect of bay laurel (Laurus nobilis) (LE) and rosemary (Salvia rosmarinus) (RE) extracts, in two free forms and loaded with liposome, on the behavior of Listeria monocytogenes and Vibrio parahaemolyticus in silver carp (Hypophthalmichthys molitrix) minced, were examined. After extraction, the extracts were evaluated for phenolic, flavonoid, and antibacterial compounds (determination of MIC and MBC). The treatments studied included control treatment, treatments containing 1 and 1.5% of free extracts, and treatments containing 1 and 1.5% of liposome-coated extracts of LE and RE which were examined at times of 0, 4, 8, and 12 days with 3 replications. The findings indicated that the amount of flavonoid and phenolic compounds and the results of antibacterial tests (MIC and MBC tests) in RE extract were more favorable than LE extract. The aqueous extract of rosemary had higher levels of phenolic (344.66 mg gallic acid/g extract) and flavonoid (245.33 mg Catechin/g extract) compounds compared to the bay laurel extract (257.66 mg gallic acid/g extract) and (151.26 mg Catechin/g extract) respectively. The results of the behavior of L. monocytogenes and V. parahaemolyticus in fish showed that with increasing the storage time at 4 °C, these parameters increased, but in the treatment containing the coated forms of LE and RE extracts (concentration 1.5%), changes were significantly slower than other treatments. According to the obtained results, it can be concluded that in general, adding extracts of bay laurel and rosemary in a concentration of 1.5% reduces the proliferation of bacteria that cause food poisoning.

Assessment of Risk Factors and Clinical Outcomes in Hospitalized COVID-19 Patients with Candida spp. Co-infections: Species Distribution and Antifungal Susceptibility Patterns of Isolates

INTRODUCTION

Fungal co-infections are considered an important complication in hospitalized patients with SARS-CoV-2 that can be attributed to disease aggravation, increased mortality, and poor outcomes. This study was conducted to determine the species distribution and antifungal susceptibility patterns of Candida isolates from hospitalized COVID-19 patients in Shiraz, Iran, in addition to associated risk factors and outcomes of co-infections with Candida species.

MATERIALS AND METHODS

In this single-center study, a total of 106 hospitalized COVID-19 patients were evaluated for clinical characteristics and outcomes. Species identification was performed by ITS1-5.8S-ITS2 gene sequencing. Antifungal susceptibility testing to fluconazole, itraconazole, voriconazole, posaconazole, caspofungin, amphotericin B, and nystatin was determined according to the M27-A3/S4 CLSI protocol.

RESULTS

Candida species were recovered from 48% (51/106) of hospitalized COVID-19 patients. Statistical analysis showed that patients who had heart failure, bacterial co-infection, and were receiving empirical antifungal therapy had a higher risk of developing Candida co-infection. In total, 71 Candida isolates were recovered, of which C. albicans (69%) was the most prevalent isolate. The majority of the Candida isolates were susceptible to all classes of tested antifungal drugs.

DISCUSSION

Our results elucidate a high rate of Candida co-infections among hospitalized COVID-19 patients. Comorbidities such as heart failure, HTN, COPD, bacterial infections as well as therapeutic interventions including catheterization, mechanical ventilation, and ICU admission increased the risk of Candida spp. isolation from the bloodstream, respiratory tract and urine samples, which led to a higher in-hospital mortality rate. Additionally, obtained data clarified that empirical antifungal therapy was not as successful as anticipated.

Assessment of virulence factors and antimicrobial resistance among the Pseudomonas aeruginosa strains isolated from animal meat and carcass samples

BACKGROUND

Pseudomonas aeruginosa bacteria are emerging causes of food spoilage and foodborne diseases. Raw meat of animal species may consider a reservoir of P. aeruginosa strains.

OBJECTIVES

The present survey was done to assess the prevalence, antibiotic resistance properties and distribution of virulence factors among the P. aeruginosa strains isolated from raw meat and carcass surface swab samples of animal species.

METHODS

Five hundred and fifty raw meat and carcass surface swab samples were collected from cattle and sheep species referred to as slaughterhouses. P. aeruginosa bacteria were identified using culture and biochemical tests. The pattern of antibiotic resistance was determined by disk diffusion. The distribution of virulence and antibiotic resistance genes was determined using polymerase chain reaction.

RESULTS

Forty-seven of 550 (8.54%) examined samples were contaminated with P. aeruginosa. The prevalence of P. aeruginosa in raw meat and carcass surface swab samples were 6.57 and 12%, respectively. P. aeruginosa isolates showed the maximum resistance rate toward penicillin (87.23%), ampicillin (85.10%), tetracycline (85.10%), gentamicin (65.95%) and trimethoprim (57.44%). The most commonly detected antibiotic resistance genes were BlaCTX-M (53.19%), blaDHA (42.55%) and blaTEM (27.65%). The most commonly detected virulence factors was ExoS (42.55%), algD (31.91%), lasA (31.91%), plcH (31.91%) and exoU (25.53%).

CONCLUSIONS

Meat and carcass surface swab samples may be sources of resistant and virulent P. aeruginosa, which pose a hygienic threat in their consumption. However, further investigations are required to identify additional epidemiological features of P. aeruginosa in meat and carcass surface samples.

Fear of COVID-19 Higher among Food-Insecure Households: A Model-Based Study, Mediated by Perceived Stress among Iranian Populations

Objective: The COVID-19 pandemic is a crisis accompanied by multiple psychological consequences (including fear of COVID-19) and threatens the food security status of millions of people. This study aimed to examine the association between fear of COVID-19 and food insecurity, mediated by perceived stress. Method : This cross-sectional study was conducted among 2871 Iranian participants (18-80 years), recruited through the Social Media during the COVID-19 epidemic. The demographic and socio-economic information questionnaire, Household Food Insecurity Access Scale (HFIAS), COVID-19 fear scale (FCV-19S), Cohen's Perceived Stress Scale (PSS-14) and Perceived Social Support Questionnaire (MSPSS) were used in data gathering. Descriptive and analytical analyses were done using SPSS 22.0 and Amos 22.0 was used for structural equation modeling (SES). Results: Food insecurity has significant positive direct and indirect (mediated by perceived stress) correlations with fear of COVID-19 (P < 0.05). It was also shown that perceived social support could negatively relate to fear of COVID-19 through the pathways of food security status or perceived stress (P < 0.05). Among women, the presence of a child under 5 had a significant direct association with fear of COVID-19 (P < 0.05). Conclusion: Food insecurity was associated with more perceived fear of COVID-19 among the studied population. The crisis caused by COVID-19 highlights the need to increase social resilience through developing and implementing appropriate strategies to prevent and mitigate social costs (whether physical, psychological, or nutritional).

Concept of Food in Persian Medicine

In Persian Medicine (PM), food is considered as a basic concept, the proper understanding of which, will prove beneficial in nutrition of healthy individuals and diet therapy of patients. The objective of this article is to examine the defining attributes of the concept of food in PM. Concept analysis was performed using Walker & Avant's approach, comprising eight stages of 1) selecting a concept; 2) determining the objective of analysis; 3) identifying all uses of the concept; 4) determining the defining attributes of the concept; 5) constructing a model case; 6) constructing borderline, contrary and invented cases; 7) identifying antecedents and consequences; and 8) defining empirical referent. The results showed that, the defining attributes of the concept of food in PM are: 1) replacement of body tissues and organs; 2) resemblance to tissues and organs; 3) adding to body quantity; 4) prerequisites for childbirth; 5) delicious and sweet or tasteless or greasy flavors; and 6) production of blood humors, warmth and moisture. In order to clarify the concept, borderline, contrary and invented cases were also presented. The results of this study can provide an objective and understandable picture of the use of the concept of food for researchers and open new horizons in nutrition and diet therapy.

MicroRNAs and their implications in CD4+ T-cells, oligodendrocytes and dendritic cells in multiple sclerosis pathogenesis

MicroRNAs (miRNAs) have been established as key players in various biological processes regulating differentiation, proliferation, inflammation, and autoimmune disorders. Emerging evidence suggests the critical role of miRNAs in the pathogenesis of multiple sclerosis (M.S.). Here, we provide a comprehensive overview on miRNAs which are differentially expressed in M.S. patients or experimental autoimmune encephalomyelitis (EAE) mice and contribute to M.S. pathogenesis through regulating diverse pathways including CD4+ T cells proliferation, differentiation, and activation in three subtypes of CD4+ T cells including Th1, Th17 and regulatory T cells (Tregs). Moreover, regulation of oligodendrocyte precursor cells (OPC) differentiation as a crucial player of M.S. pathogenesis is also described. Our literature research showed that miR-223 could affect different pathways involved in M.S. pathogenesis, such as promoting Th1 differentiation, activating the M2 phenotype of myeloid cells, and clearing myelin debris. MiR-223 was also identified as a potential biomarker, distinguishing relapsing-remitting multiple sclerosis (RRMS) from progressive multiple sclerosis (PMS), and thus, it may be an attractive target for further investigations. Our overview provides a novel, potential therapeutic targets for the treatment and new insights into miRNAs' role in M.S. pathogenesis.

Effect of clover sprouts protein hydrolysates as an egg substitute on physicochemical and sensory properties of mayonnaise

Mayonnaise is a semi-solid oil-in-water emulsion that in addition to eggs other stabilizers and thickeners are used as emulsifiers for better stability. Although eggs are an important ingredient in the production of mayonnaise, the health problems associated with the use of eggs is increasing due to their high cholesterol content. The aim of this study was to evaluate the feasibility of clover sprout protein hydrolysates (CSPH) to replace eggs for the production mayonnaise. First, CSPH was produced using alcalase and flavourzyme enzyme, and in order to find the best enzyme, the degree of hydrolysis (DH) and protein recovery (PR) were determined. Then four mayonnaise treatments included, T1: control (egg 9%), T2: egg 6%+ CSPH 3%, T3: egg 3%+ CSPH 6%, T4: egg 0%+ CSPH 9% was prepared and the stability, viscosity, physicochemical, textural, and sensory properties of mayonnaise was investigated. The samples containing CSPH showed that CSPH had high essential amino acids, CSPH from alcalase enzyme had higher amounts of protein, DH, PR, and increasing hydrolysis time had a positive effect on these parameters (p < .05); therefore, CSPH from alcalase enzyme was used for the production mayonnaise. The stability, viscosity, firmness, adhesion of texture, and pH increased with increasing CSPH, while the brightness, acidity, and sensory score of the samples decreased (p < .05). In general, T3 had an acceptable quality in terms of the studied characteristics, but sensory score in T4 could not be confirmed. Hence, by replacing eggs with CSPH up to 6%, mayonnaise with appropriate physicochemical and sensory properties can be produced. Therefore, the formulation egg 3%+ CSPH 6% is an appropriate choice to produce mayonnaise for consumers who are on a restricted diet to eat foods containing eggs.

Molecular detection of fowl adenovirus 7 from slaughtered broiler chickens in Iran: the first report

Background

Fowl adenoviruses (FAdVs) are responsible for a variety of clinical symptoms, with an increasing significance in the poultry industry throughout the world. Typical diseases caused by FAdVs include inclusion body hepatitis (IBH), hepatitis-hydropericardium syndrome (HHS), gizzard erosion (GE), respiratory disease, and hemorrhage in muscles and organs.

Aims

During 2020, broiler chickens from the north of Iran showed ecchymotic and petechial hemorrhages in thigh and breast muscles at the slaughterhouse. Hemorrhages were observed in 10% to 60% (with an average of 20-30%) of chicks per flock. To find out the etiology of these lesions, the present study was conducted.

Methods

Different environmental factors were investigated, and FAdV, infectious bursal disease virus (IBDV), and chicken infectious anemia virus (CIAV) were detected using molecular assays.

Results

Among the viruses tested, FAdV was detected by polymerase chain reaction (PCR), and sequence analysis clustered the virus into species E, serotype 7.

Conclusion

This is the first report on FAdV-7 existence among poultry in Iran. Effective screening of the chicks at slaughtering age should be performed from the whole country.

910 The Value of a Compressive Base Layer Bandaging in Post-Surgical Plaster Application: Reductions in Early Face-To-Face Times and Early Dressing Changes. Improved Patient and Plaster Technician Satisfaction

Aim

Plaster immobilisation alongside wound compression after surgery is often required but not easy to balance. If a plaster is too loose then it may not produce sufficient wound compression but if the cast is too restrictive it may be uncomfortable and lead to complications. Our aim is to provide a technique that addresses these imbalances.

Method

Compressive base layer banding technique involves tightly wrapping the wound dressing with wool and crepe then applying a well-padded plaster on top. The technique was prospectively audited and compared to other practice within our centre. The aims were to show that the technique was safe and to look for potential benefits for patients and healthcare staff. Both groups included trauma and elective patients treated by a similar set of foot and ankle operations. We audited patients on their experiences, concerns and time spent having their cast changed.

Results

Primarily, the results showed that the technique was safe with no severe complications. The time for a plaster change reduced by a third, from 24 minutes (control group n = 28) to 16 minutes (intervention group n = 27). Dressing changes at the same time were reduced by 80%. The intervention group were happier with their casts, had lower levels of concerns regarding their attendance and their risk of infection.

Conclusions

Our audit has shown that the compressive bandaging technique is safe (non-inferior) compared to current practices at our hospital. The technique has the benefit of reducing the time patients spend being face-to-face during plaster change and reduces both their discomfort and concern.

Exposure to waterpipe smoke and blood heavy metal concentrations

Waterpipe (WP) smoking is a global phenomenon, with the most consumers in Middle East countries and China. Heavy metals exposure related to WP smoking has been associated with many adverse health effects. However, the association of lifestyle factors and smoking habits with blood heavy metals concentration in WP smokers is unclear yet. Therefore, we aimed to investigate the relationship of lifestyle factors (i.e., diet and physical activity) and smoking habits (i.e., duration of the use of WP and times of smoking WP per week) with blood concentrations of lead (Pb) and cadmium (Cd). This cross-sectional study was based on 86 WP smokers in Khalkhal, Iran (2018). Graphite furnace atomic absorption spectrometry (GFAAS) was used to measure heavy metals. The median (interquartile range (IQR)) of Pb and Cd concentrations were 39 (24) and 1.3 (1.2) μg/L. The blood Pb and Cd levels were significantly higher in participants with lower education level (P-value = 0.049 and 0.041, respectively). An IQR increase in physical activity per week was associated with -0.12 μg/L (95% confidence interval (CI): -0.23, -0.01, P-value = 0.04) decrease in Pb concentration. An increase in the times of consuming fruit per week was negatively associated with the concentration of Cd. Overall, our findings suggested that physical activity and healthy diet have been associated with lower blood heavy metal concentrations in WP smokers; however, further studies are needed to confirm these findings.

Manufacturing and evaluation of a multi-purpose Iranian head and neck anthropomorphic phantom called MIHAN

A new multi-purpose Iranian head and neck (MIHAN) anthropomorphic phantom was designed and manufactured to be used in diagnostic and therapeutic applications. Geometry of MIHAN phantom was determined based on the average dimensions acquired by CT scans of twenty patients without any medical problems in their head and neck site. Because the phantom was expected to be used with different modalities with a wide range of photon energies, attenuation coefficients of some selected materials were determined using Monte Carlo simulation. Based on analytical and simulation results, acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) were found suitable choices for soft and bony tissues, respectively. They were used in the 3D printer to build the phantom. The suitability of the materials was checked by CT number value comparison between the organs included in the phantom and the corresponding body tissues and also film dosimetry of a typical intensity-modulated radiation therapy (IMRT) plan.. Hounsfield Unit agreement and 95% ± 2% pass rate for the IMRT plan verification proved the suitability of material selection. Also, the film dosimetry showed feasibility of using MIHAN in radiotherapy plan verification workflow. In addition, PLA was introduced as a spongy bone tissue substitute for the first time.

Mathematical analysis of a stochastic model for spread of Coronavirus

This paper is associated to investigate a stochastic SEIAQHR model for transmission of Coronavirus disease 2019 that is a recent great crisis in numerous societies. This stochastic pandemic model is established due to several safety protocols, for instance social-distancing, mask and quarantine. Three white noises are added to three of the main parameters of the system to represent the impact of randomness in the environment on the considered model. Also, the unique solvability of the presented stochastic model is proved. Moreover, a collocation approach based on the Legendre polynomials is presented to obtain the numerical solution of this system. Finally, some simulations are provided to survey the obtained results of this pandemic model and to identify the theoretical findings.

Ibuprofen Protection Against Restrained Chronic Stress-induced Depression in Male Rats

Introduction:

Stress predisposes organisms to depression and cognitive impairments, and seems to interact with metabolic homeostasis. The inflammatory response and the upregulation of proinflammatory cytokines are some of the consequences related to chronic stress. In this study, we investigated the preventive effect of chronic administration of ibuprofen, as an inhibitor of cyclooxygenases, on the cognitive and behavioral alterations and the weight gain reduction induced by simultaneous chronic restraint stress in rats.

Materials and Methods:

Male Wistar rats were subjected to chronic restraint stress and injected daily with the variable doses of ibuprofen or vehicle, for 21 consecutive days. Then, all animals were tested with the forced swim test and passive avoidance conditioning. Also, the weight of the animals was recorded before and after the interventions. Ultimately, plasma interleukin 6 (IL-6) levels were measured.

Results:

Chronic stress increased depressive-like behaviors, impaired learning, and disrupted the normal weight gain. However, the animals that received the highest dose of ibuprofen showed less depressive-like behaviors, a better avoidance memory, and a higher weight gain. However, the level of plasma IL-6 did not differ significantly between the study groups.

Conclusion:

The administration of ibuprofen prevents the cognitive and behavioral consequences of chronic stress. During the recovery, the plasma levels of IL-6 were not elevated by stress, and the IL-6 levels did not predict the behavioral performance of the stressed animals. The exact mechanisms of the protective effects of ibuprofen against chronic stress need to be further investigated.

Implementation of Combinational Deep Learning Algorithm for Non-alcoholic Fatty Liver Classification in Ultrasound Images

Background

Nowadays, fatty liver is one of the commonly occurred diseases for the liver which can be observed generally in obese patients. Final results from a variety of exams and imaging methods can help to identify and evaluate people affected by this condition.

Objective

The aim of this study is to present a combined algorithm based on neural networks for the classification of ultrasound ‎images from fatty liver affected patients.

Material and Methods

In experimental research can be categorized as a diagnostic study which focuses on classification of the acquired ultrasonography images for 55 patients with fatty liver. We implemented pre-trained convolutional neural networks of Inception-ResNetv2, GoogleNet, AlexNet, and ResNet101 to extract features from the images and after combining these resulted features, we provided support vector machine (SVM) algorithm to classify the liver images. Then the results are compared with the ones in implementing the algorithms independently.

Results

The area under the receiver operating characteristic curve (AUC) for the introduced combined network resulted in 0.9999, which is a better result compared to any of the other introduced algorithms. The resulted accuracy for the proposed network also caused 0.9864, which seems acceptable accuracy for clinical application.

Conclusion

The proposed network can be used with high accuracy to classify ultrasound images of the liver to normal or fatty. The presented approach besides the high AUC in comparison with other methods have the independence of the method from the ‎user or expert interference.

Identification of Conformational B-cell Epitopes in Diphtheria Toxin at Varying Temperatures Using Molecular Dynamics Simulations

The changes in temperature levels can potentially affect the toxins in terms of stability and immunological properties via alteration of their structures. Diphtheria Toxin (DT) is highly considered by scientists since its mechanism of action is similar to those of most bacterial toxins, such as botulinum, tetanus, and anthrax. The protection of conformational B-cell epitopes is critically important in the process of diphtheria vaccine production. This study aimed to evaluate the conformational changes of the DT structure at three different temperature levels (27˚C, 37˚C, and 47˚C) using molecular dynamic simulations. Secondary structures were analyzed in YASARA software. According to the results, significant decreases were observed in percentages of the &beta;-sheets, turns, and the helices of the DT structure at 47˚C in comparison with those at 27˚C and 37˚C. Furthermore, the tertiary structure of the DT was compared at different temperatures using the contact map. Accordingly, the results showed that the root-mean-square deviation of the DT structure increased upon temperature rising. In addition, amino acids D68, G128, G171, C186, and K534-S535 at 27˚C and 37˚C, as well as amino acids G26, P38, S291, T267, H384, A356, and V518 at 47˚C showed higher root mean square fluctuation values. The finding demonstrated that the stability of the DT structure decreased at high temperature (47˚C). The solvent-accessible surface area diagram showed that the hydrophobicity of the DT structure increased via temperature rising, and the amino acid residues belonging to B-cell epitopes extended through increasing temperature. However, B-cell epitopes belonging to the junction region of chains A and B were only present at 37˚C. The results of this study are expected to be applicable for determining a suitable temperature level for the production process of the diphtheria vaccine.

A mathematical model to examine the effect of quarantine on the spread of coronavirus

In this study, we propose a mathematical model about the spread of novel coronavirus. This model is a system of fractional order differential equations in Caputo's sense. The aim is to explain the virus transmission and to investigate the impact of quarantine on decreasing the prevalence rate of the virus in the environment. The unique solvability of the presented COVID-19 model is proved. Also, the equilibrium points and the reproduction number of the proposed model are discussed in two cases with and without considering the quarantine factor. Using the Adams-Bashforth-Moulton predictor-corrector method, some numerical simulations are implemented to survey the behavior of the considered model.

The risk of malignancies in patients receiving hematopoietic stem cell transplantation: a systematic review and meta-analysis

INTRODUCTION

Hematopoietic stem cell transplantation (HSCT) is widely used in the treatment of malignant and non-malignant diseases. Due to advances in the number of survivors of this treatment, the number of survivors is increasing, but the late complications of this therapeutic approach such as secondary cancers have been long term and have not been fully controlled.

METHODS

The present meta-analysis study was performed by considering English-language articles in the databases including Web of Science, Scopus and PubMed. This meta-analysis included cohort studies that reported an incidence of cancer following stem cell transplantation (SCT). Random/fixed effect size meta-analyses were used to standardize the incidence ratio for different cancers.

RESULTS

22 studies that evaluated patients receiving SCT (n = 270,063) were included in the study. The study found 9233 cases of cancer after transplantation. Meta-analysis showed that the risk of cancer after SCT was SIR = 1.66 (95% CI 1.47-1.86). The most common cancers observed in SCT recipients were bone tissue, head and neck cancers, and melanoma, with SIRs of 10.04 (3.48-16.61), 6.35 (4.76-7.93) and 3.52 (2.65-4.39), respectively.

CONCLUSION

The meta-analysis findings showed that the risk of secondary cancers after HSCT was significantly increased in most types of cancers. Consequently, diagnostic tests for common cancers should be included in the screening program of these patients for the prevention and early detection of high-risk cancers.

A mesoscopic numerical study of shear flow effects on asphaltene self-assembly behavior in organic solvents

A significant amount of research work has been conducted to shed light on the asphaltene aggregation behavior under no-flow conditions. However, their aggregation under shear flow conditions is poorly understood mainly due to the lack of research studies performed on this subject. In this work, we employ the Brownian dynamics simulation to examine the shear flow effects on the self-assembly behavior of asphaltenes. Three volume fractions φ of asphaltene nanoaggregates, ranging from 1 to 7%, are used to investigate the asphaltene aggregation behavior in heptane and heptol (i.e., a solvent containing both heptane and toluene) solvents under shear rates of [small gamma, Greek, dot above] = 0.0-2.5 × 108 s-1. The shear is applied parallel to the x-axis and the shear-gradient is along the y-axis. Under shear flow conditions, the formation of the percolating networks of aggregates is triggered at φ = 3% which is lower than that under the no-flow conditions, i.e., φ = 7%. In both solvent systems, the formed networks mainly percolate along the x- or z-axis to experience less shear-gradient. At all volume fractions, an increase in the shear rate from [small gamma, Greek, dot above] = 0.0 to [small gamma, Greek, dot above] = 2.5 × 108 s-1 resulted in two to three orders of magnitude improvement in the self-diffusion coefficients of colloids.