The intermolecular interactions of branching onto collagen chains and its effects on the formation of nanocomposite fibres

Collagen is an important biomimetic material. Several attempts to electrospin this biopolymer have proved difficult due to significant denaturation and degradation occurring while being dissolved in a solvent and spun. Acid soluble collagen (ASC) was successfully pre-treated by grafting Methyl Methacrylate-coEthyl Acrylate onto its chains leading to ASC-g-poly(methyl methacrylate-co-ethyl acrylate) (CME). This was not only to add stability to its structure but also allowed electrospinning of the material which would otherwise have a deteriorating effect on its degradation rate and would have required post treatment. Experimental relations depending on monomer feed ratios and physiochemical properties of side chains that affect fibre formation, diameter, and distribution were investigated. Increasing the number of branching onto ASC chains can significantly reduce the deteriorative impact of electrospinning conditions along with improving its stability in high humidity conditions. The short chain branching onto ASC chains can effectively influence the fibre thermal stability while long chain branching provides a higher density of chain entanglements that improves fibre uniformity. The study has shown how to process a composite fibre which can consist of CME with a structurally and electrically incompatible polymer, by using coaxial electrospinning. Nylon 66 has been taken as an example of this methodology. By tailoring the intensity of the electric field, different fibre content was achieved from the core and shell components, leading to varied physical properties; thermal, mechanical and degradability. The effect of chain orientation and intermolecular interactions between two structurally different polymer chains were investigated; custom-built electrostatics and supplementary bonding e.g. hydrogen bonds were identified the major factors for the design of reinforced CME/nylon 66 core-shell fibres. Finally, a functionalisation methodology has been successfully established in which SMART nanofillers, such as graphene oxide (GO) is attached to CME. By increasing the GO content, significantly increases were achieved in the performance of polymerisation onto ASC. This nanofiller can improve the physiochemical properties of ASC chains, the same as the grafted side chains. It was found that humidity and temperature play key roles in the degradation rate of GO-CME composite; above 50 oC, GO is not as stable as branches on the surface of collagen chains. The impact of this research is in the ability of collagen to be used in a variety of applications by making it more stable via grafting from new end groups. In consequence, new methodologies in electrospinning of nanofibres; composite fibres and smart nanofillers become possible, imparting new properties and new possibilities of this biopolymer for numerous end uses

Validity and Reliability of Adult ADHD Self-Report Scale Persian Version (ASRS-V1.1-Persian)

Background: Attention-deficit/hyperactivity disorder (ADHD) is a common mental disorder in adults. The objective of this study was to develop a valid Persian version of the 18-question ASRS-V1.1 according to WHO translation protocol and report its psychometric properties. Methods: In the first step, we translated the original 18-question ASRS-V1.1 version into Persian under the supervision of the WMH-CIDI advisory committee. The process of adaptation was consisting of forward-translation, expert panel evaluation, back translation, cross-cultural adaptation, pre-testing, and final adjustment. In the second step, we conducted a cross-sectional study with 734 students were studied in Shahroud in 2013. A sub-sample of subjects consists of 99 students were clinically interviewed according to DSM-IV-TR criteria by a well-trained physician. Results: The ASRS-V1.1-P had satisfactory internal consistency (Cronbach’s alpha = 0.85). Sensitivity and specificity for the first six questions of ASRS-V1.1-P were 50.0% (95% CI: 30.3-69.6) and 80.5% (95%CI: 70.7-88.3), respectively. Finally, 43 subjects (5.5%) were confirmed for adult ADHD. There was not sex predominance in the prevalence of ADHD. Conclusion: Totally, it may be concluded that adult ADHD is a common problem among students and prevention of this disorder is crucial to reduce the probable subsequent social, educational, and job problems in future. The 18-question ASRS-V1.1-P is a psychometrically reliable and valid measure for screening ADHD in adults.  Keywords:  Attention-deficit/hyperactivity disorder, Screening, Adult, Validity

Application of inclusive multiple model for the prediction of saffron water footprint

Applying new approaches in the management of water resources is a vital issue, especially in arid and semi-arid regions. The water footprint is a key index in water management. Therefore, it is necessary to predict its changes for future durations. The soft computing model is one of the most widely used models in predicting and estimating agroclimatic variables. The purpose of this study is to predict the green and blue water footprints of saffron product using the soft computing model. In order to select the most effective variables in prediction water footprints, the individual input was eliminated one by one and the effect of each on the residual mean square error (RMSE) was measured. In the first stage, the Group Method of Data Handling (GMDH) and evolutionary algorithms have been applied. In the next stage, the output of individual models was incorporated into the Inclusive Multiple Model (IMM) as the input variables in order to predict the blue and green water footprints of saffron product in three homogenous agroclimatic regions. Finally, the uncertainty of the model caused by the input and parameters was evaluated. The contributions of this research are introducing optimized GMDH and new ensemble models for predicting BWF, and GWF, uncertainty analysis and investigating effective inputs on the GWF and BWF. The results indicated that the most important variables affecting green and blue water footprints are plant transpiration, evapotranspiration, and yield, since removing these variables significantly increased the RMSE (range=11–25). Among the GMDH models, the best performance belonged to NMRA (Naked Mole Ranked Algorithm) due to the fast convergence and high accuracy of the outputs. In this regard, the IMM has a better performance (FSD=0.76, NSE=0.95, MAE) = 8, PBIAS= 8) than the alternatives due to applying the outputs of several individual models and the lowest uncertainty based on the parameters and inputs of the model (p = 0.98, r = 0.08)

The relationship between hemodialysis patients’ treatment adherence, procrastination, and difficulty in emotion regulation: A cross-sectional study in southeast Iran

BackgroundEnd-stage renal disease is a life-threatening condition in which patients require dialysis or kidney transplant. These patients must adhere to the treatment regimen because treatment non-adherence affects their quality of life and health. We conducted this study to predict hemodialysis patients’ treatment adherence based on procrastination and difficulty in emotion regulation.Materials and methodsWe conducted this descriptive correlational study on 218 hemodialysis patients with chronic kidney disease. We used purposive sampling to select participants from six dialysis centers in Kerman, Sirjan, and Rafsanjan. The measuring tools included the end-stage renal disease adherence questionnaire, general procrastination scale, decisional procrastination scale, and difficulty in emotion regulation scale. We used the correlation coefficient, regression analysis, and SPSS18 to analyze data.ResultsOur study indicated that among the dimensions of treatment adherence, medication use had a significant, weak, and inverse relationship with general and decisional procrastination. We also found a significant, weak, and inverse relationship between attendance and general procrastination (p < 0.05 and p < 0.01). But there is no significant relationship between treatment adherence, general procrastination, and decisional procrastination (p > 0.05). Multivariate regression analysis revealed a relationship between age, the cause of kidney failure, and treatment adherence (p = 0.01 and p = 0.02).ConclusionTreatment non-adherence causes problems and complications in hemodialysis Patients, and disrupts their course of treatment. Therefore, it is necessary to identify the factors influencing non-adherence of patients undergoing hemodialysis and improve their treatment adherence, and thus their quality of life

The Hospitalization Rate of Cerebral Venous Sinus Thrombosis before and during COVID-19 Pandemic Era: A Single-Center Retrospective Cohort Study

Objectives: There are several reports of the association between SARS-CoV-2 infection (COVID-19) and cerebral venous sinus thrombosis (CVST). In this study, we aimed to compare the hospitalization rate of CVST before and during the COVID-19 pandemic (before vaccination program). Materials and methods: In this retrospective cohort study, the hospitalization rate of adult CVST patients in Namazi hospital, a tertiary referral center in the south of Iran, was compared in two periods of time. We defined March 2018 to March 2019 as the pre-COVID-19 period and March 2020 to March 2021 as the COVID-19 period. Results: 50 and 77 adult CVST patients were hospitalized in the pre-COVID-19 and COVID-19 periods, respectively. The crude CVST hospitalization rate increased from 14.33 in the pre-COVID-19 period to 21.7 per million in the COVID-19 era (P = 0.021). However, after age and sex adjustment, the incremental trend in hospitalization rate was not significant (95% CrI: -2.2, 5.14). Patients \u3e 50-year-old were more often hospitalized in the COVID-19 period (P = 0.042). SARS-CoV-2 PCR test was done in 49.3% out of all COVID-19 period patients, which were positive in 6.5%. Modified Rankin Scale (mRS) score ≥3 at three-month follow-up was associated with age (P = 0.015) and malignancy (P = 0.014) in pre-COVID period; and was associated with age (P = 0.025), altered mental status on admission time (P\u3c0.001), malignancy (P = 0.041) and COVID-19 infection (P = 0.008) in COVID-19 period. Conclusion: Since there was a more dismal outcome in COVID-19 associated CVST, a high index of suspicion for CVST among COVID-19 positive is recommended

One-Step Fabrication of Three-Dimensional Fibrous Collagen-Based Macrostructure with High Water Uptake Capability by Coaxial Electrospinning

One step fabrication of the three dimension (3D) fibrous structure of Collagen-g-poly(MMA-co-EA)/Nylon6 was investigated by controlling the experimental conditions during coaxial electrospinning. This 3D fibrous structure is the result of interactions of two polymeric systems with a varied capability to be electrostatically polarized under the influence of the external electric field; the solution with the higher conductivity into the inner spinneret and the solution with the lesser conductivity into the outer capillary of the coaxial needle. This set-up was to obtain bimodal fiber fabrication in micro and nanoscale developing a spatial structure; the branches growing off a trunk. The resultant 3D collagen-based fibrous structure has two distinguished configurations: microfibers of 6.9 ± 2.2 µm diameter gap-filled with nanofibers of 216 ± 49 nm diameter. The 3D fibrous structure can be accumulated at an approximate height of 4 cm within 20 min. The mechanism of the 3D fibrous structure and the effect of experimental conditions, the associated hydration degree, water uptake and degradation rate were also investigated. This highly stable 3D fibrous structure has great potential end-uses benefitting from its large surface area and high water uptake which is caused by the high polarity and spatial orientation of collagen-based macrostructure