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Studies have reported a sex bias in case fatalities of COVID-19 patients. Moreover, it is observed that men have a higher risk of developing a severe form of the disease compared to women, highlighting the importance of disaggregated data of male and female COVID-19 patients. On the other hand, other factors (eg, hormonal levels and immune functions) also need to be addressed due to the effects of sex differences on the outcomes of COVID-19 patients. An insight into the underlying causes of sex differences in COVID-19 patients may provide an opportunity for better care of the patients or prevention of the disease. The current study reviews the reports concerning with the sex differences in COVID-19 patients. It is explained how sex can affect angiotensin converting enzyme-2 (ACE2), that is a key component for the pathogenesis of COVID-19, and summarized the gender differences in immune responses and how sex hormones are involved in immune processes. Furthermore, the available data about the impact of sex hormones on the immune functions of COVID-19 cases are looked into.
The purpose of this study is comparing attentional bias in patients with obsessive - compulsive disorder (OCD) with matched healthy individuals. In this cross - sectional study 46 patients with obsessive-compulsive disorder are compared with 46 healthy individual by means of convenient sampling. Emotional Stroop test is used for evaluation. Data were analyzed through Student t-test. Finding shows significance difference between two groups (P value < 0.05). Correct response is more in healthy groups that patient (p = .04). Attention bias in OCD patient might be caused difficulties in disengagement and inhibition of attention to threaten stimuli.
The purpose of the current research was to study the relationship of life skills and self-esteem development with test anxiety and school performance in female students in the schools of Babol city in Mazandaran province. The sample size of the research involved 150 students selected by random cluster sampling.
Participants were asked to answer Questionnaire on Life Skills and Self-Esteem Inventory by Cooper Smith and Test Anxiety Inventory by Sarrason while their previous term average(mean scores) was considered as a criterion for their school performance. Results of the research showed that there was a significant correlation between part of the factors embedded in Life Skills and Test Anxiety Inventory. Also, significant correlations between self-esteem and test anxiety and self-esteem and life skills were observed. However, no significant link was found between self-esteem and school performance. Furthermore, results from step by step regression testing revealed that only self-esteem made a significant contribution as a predicting factor to test anxiety as compared to another variable, namely life skills.
The present research will examine the effectiveness of music on social skills in male students who are mentally retarded but educable.
This research applied an experimental method with pre-test and post-test tools. Therefore, to carry out the research, 40 eligible students were chosen from three especial schools in such cities as Amol (Bahmand school), Babol (Kusha school) and Noor (Tulo-e-Noor school) in Mazandaran province in Iran. Afterwards, they were randomly divided into two groups, namely control and experimental ones. Both Demographic Data Collection and Social Skill Development (by Vineland) Questionnaires were used to pile up the data. in addition to being provided by teachers' teaching, the experimental groups were exposed to rhythmic -melodious music for 12 sessions weekly, 10 minutes per session, as compared to the control groups who have been educated without the dependent variable (i.e. absent of rhythmic -melodious music).
Results from covariance analysis revealed that after the scores of pre-test and other variables related to social skills had been checked, there existed a significant difference between the mean of remained scores in control and experimental groups. That is, the mean score of experimental group was significantly higher than that of control group (P=0).Eta square root equaling 1 explained 58% of covariance of remained scores (personal differences) in regard to musical effects.
Results of the research indicate that rhythmic -melodious music can be considered as one of the factors affecting socially developmental skills in especial children.
This study aims to compare the extent of mental stress between mentally retarded and normal children’s parents.
The study had a post-event survey design (causal- comparative one). The sample size including 120parents with mentally retarded children and 120 parents with normal kids was selected through clustering multi-stage sampling method. Questionnaire on Resources and Stress (QRS) developed by Friedrich et al was used to examine the degree of parental stress. Accordingly, by applying statistical t-tests for independent samp and Pearson correlation coefficient, the research data were analyzed.
Results from this study showed that a significant difference was found at stress level between parents with mentally retarded children and those with healthy kids. in fact, the degree of mental stress amongst parents with mentally retarded children was turned out to be much more than that of in parents with normal children (P< 0.01).No significant difference was observed between mothers and fathers having children with mental retardation in terms of mental stress. That is, both fathers and mothers with mentally retarded kids suffered from the same degree of mental stress. Despite the fact that parents’ stress had nothing to do with child’s gender, it significantly increased with mentally retarded child’s age(P=0.01). On the other hand, the more the age of the mentally disabled child was, the more the stress of parents would be. Also, the relationship of parents’ literacy level with degree of stress was significantly different (P< 0.01).
The purpose of this study is comparing executive functions in patients with obsessive - compulsive disorder (OCD) and matched healthy individual. In this cross - sectional study were evaluated 46 patients with obsessive-compulsive disorder are compared with 46 healthy individual by means of convenient sampling. In this retrospective, causal-comparative study, Stroop test, Wisconsin card sorting test (WCST) and continuous performance test (CPT) were used as the research tools. Data were analyzed through Student t-test. Finding show that reaction time significantly lower in OCD group ( p< 0.5). In continuous performance test omission error in OCD more than healthy group (p < 0.5); but to groups was similar in commission and reaction time. In WCST healthy group have better performance in preservation error and correct response (p < 0.5). OCD could be considered as dysfunction of executive functions.
The aim of this study was to determine the relationship between dietary total antioxidant capacity (dTAC) and risk of breast cancer among Iranian women.
In this hospital-based case–control study, dietary intake of participants was collected using a 168-item validated FFQ. Dietary TAC was assessed using FRAP assay considering. Logistic regression was used to obtain ORs for breast cancer across quartiles of dTAC.
Cancer Institute, Iran.
We included 412 women with pathologically confirmed breast cancer and 456 apparently healthy controls.
Mean dTAC was 11·3 ± 5·8 for cases and 12·1 ± 7·9 for controls. A trend towards significant inverse association was seen between dTAC and odds of breast cancer in the whole population; such that after controlling for several potential confounders, individuals in the highest quartile of dTAC were 0·39 times less likely to have breast cancer than those in the lowest quartile (0·61; 95 % CI: 0·38, 0·99, P < 0·05). In the stratified analysis by menopausal status, we found that postmenopausal women with the greatest dTAC had lower odds for breast cancer, compared with those with the lowest dTAC (0·47; 95 % CI: 0·24, 0·93, P < 0·05). This association strengthened after additional adjustment for BMI (0·28; 95 % CI: 0·11, 0·72, P < 0·05). No significant association was seen between dTAC and odds of breast cancer in premenopausal women.
We found that dietary TAC was inversely associated with risk of breast cancer, in particular among postmenopausal women. Prospective cohort studies are needed to confirm these findings.
The aims of the current study were to investigate the effect of drought stress on phenological and morphological traits of sunflower genotypes and to determine the important traits for identifying drought-tolerant and drought-sensitive cultivars. For this purpose, a lattice square-design experiment was conducted with 64 sunflower genotypes in an 8 × 8 pattern with two replications under non-stress and moisture-stress conditions (irrigation holding at the flowering stage) during 2 years 2016 and 2017. Measured and recorded traits were included the some phenological and morphological traits seeds. Sil-96 genotype showed the highest yield under both non-stress and moisture-stress conditions. Among the morphological traits, the head and stem diameters were highly significant to determine the final yield. In comparing the genotypes, it was concluded that the number of seeds per head was the most influential component affecting the yield. Furthermore, 1000-seed weight was the most important factor affecting grain yield under moisture-stress conditions. The result of association analysis study shows that 45 of inter-simple sequence repeat markers in a general linear model are associated with yield and yield component traits and 23 of them were verified in a mixed linear model (MLM) association approach. Also, 32 markers were informative for morpho-physiological traits and 24 of them verified using the MLM. Finally, 19 informative markers were identified for phenological traits and 10 of them were verified by the MLM.
Asian Houbara Chlamydotis macqueenii is a vulnerable flagship species specific to steppe, desert and semi-desert habitats of the Middle East and Central Asia. Iran provides a critical corridor in the middle of Asian Houbara’s migratory route and also hosts a relatively large proportion of wintering and breeding populations. The aim of this study was to assess the distribution and habitat suitability of both wintering and breeding populations of Asian Houbara in Iran and evaluate the effectiveness of the existing protected area network for long-term protection of the species. For this purpose, 644 occurrence points for wintering and 216 points for breeding birds were collected from 17 Iranian provinces during 2015 to 2017. We then used a consensus species distribution modelling (SDM) approach using 11 uncorrelated environmental variables to explore the distribution of Asian Houbara habitats. Results showed that climatic and topographic variations have the most significant influence on the regional-scale distribution of Asian Houbara. Of the suitable habitats recognised for the wintering and breeding populations, 40.6% and 29.6% respectively overlapped with the extent of the protected network. A high level of spatial niche similarity (78%) was observed between wintering and breeding populations. The central, eastern and south-central Iranian semi-arid regions and desert landscapes hosted the majority of both wintering and breeding houbara occurrences. Results of this study could be used for adopting direct management planning and raising the protection level of important no-hunting areas.
Interhemispheric subdural hematomas (IHSDHs) are thought to be rare. Surgical management of these lesions presents a challenge as they are in close proximity to the sagittal sinus and bridging veins. IHSDHs are poorly characterized clinically and their exact incidence is unknown. There are also no clear guidelines for the management of IHSDH.
This is a retrospective review of all admitted patients with a diagnosis of traumatic brain injury over a 4-year period at a Level I trauma centre. Clinical characteristics of all patients with subdural hematoma (SDH) and IHSDH were collected.
Of 2165 admissions, 1182 patients had acute traumatic SDHs, 420 patients had IHSDHs (1.9% of admissions and 35.5% of SDH), 35 (8.3% of IHSDH) were ≥8 mm in width. IHSDH was isolated in 16 (3.8%) of the cases. Average age was 61.7 ± 21.5 years for all IHSDHs and 77.1 ± 10.4 for large IHSDH (p < 0.001). For large IHSDH, a transient loss of consciousness (LOC) occurred in 51.5% of individuals, post-traumatic amnesia (PTA) in 47.8% of cases, and motor weakness in 37.9% of patients. Five of the large IHSDH patients presented with motor deficits directly related to the IHSDH, and weakness resolved in four of these five individuals. None were treated surgically. Progression of IHSDH width occurred in one patient.
IHSDHs are often referred to as rare entities. Our results show they are common. Conservative management is appropriate to manage most IHSDHs, as most resolve spontaneously, and their symptoms resolve as well.
LiMnxCoyNi1−x−yO2 (LMCNO) has been broadly investigated and commercialized primarily as lithium ion battery (LIB) cathodes, owing to its high operating voltage, large energy density, and superior electronic conductivity. However, poor cycling stability induced by the rapid structure degradation limits their further development. Coating is regarded as a very effective strategy to address the problem of structure degradation. Regrettably, the coating layers obtained by traditional methods are usually thick, which is not appropriate for delivering of integrated performance. As an emerging coating technology, atomic layer deposition (ALD) demonstrates immeasurable advantages in deposition of ultrathin coating materials because of its atomic-level precision, and has been widely applied in construction of the coating layers on LMCNO substrate materials. Herein, we firstly outline the development and mechanism of ALD technology, and then systematically summarize intrinsic reasons for the enhanced electrochemical performance. Finally, we propose new insights toward designing and preparing the coating structure of LMCNO cathodes by controllable ALD for the next-generation LIBs.
The standard transthoracic echocardiography has some limitations in emergent and community-based situations. The emergence of pocket-sized ultrasound has led to influential advancements.
In this prospective study, in the hospital-based phase, children with suspected structural heart diseases were enrolled. In the school-based phase, healthy children were randomly selected from six schools. All individuals were examined by experienced operators using both the standard and the pocket-sized echocardiography.
A total of 73 individuals with a mean age of 9.9 ± 3.2 years in the hospital-based cohort and 143 individuals with a mean age of 12.8 ± 2.9 years in the school-based cohort were examined. The agreements between the standard and the pocket-sized echocardiography were good or excellent for major CHDs in both cohorts (κ statistics > 0.61). Among valvular pathologies, agreements for tricuspid and pulmonary valves’ regurgitation were moderate among school-based cohorts (0.56 [95% confidence interval 0.12–1] and 0.6 [95% confidence interval 0.28–0.91], respectively). The agreements for tricuspid and pulmonary valves’ regurgitation were excellent (>0.9) among hospital-based population. Other values for valvular findings were good or excellent. The overall sensitivity and specificity were 87.5% (95% confidence interval 47.3–99.7) and 93.8% (95% confidence interval 85–98.3) among the hospital-based individuals, respectively, and those were 88% (95% confidence interval 77.8–94.7) and 68.4% (95% confidence interval 56.7–78.6) among the school-based individuals, respectively. The cost of examination was reduced by approximately 70% for an individual using the pocket-sized device.
When interpreted by experienced operators, the pocket-sized echocardiography can be used as screening tool among school-aged population.
Triticum boeoticum is a valuable gene source for tolerance to drought stress. In order to study the effect of drought stress on this plant, and to understand its adaptive mechanisms at the molecular level, 10 accessions of T. boeoticum were evaluated under non- and drought stress conditions. Evaluation of 31 different phenological, morpho-physiological and root-related traits showed that there were significant differences between accessions. Using the bi-plot resulting from the PCA, the studied traits and accessions were separated in different groups. The most tolerant (B5) and susceptible (B6) accessions to drought stress were identified, so these accessions were used for assessment of changes in the TaNAC2 and TaNAC69-1 transcription factors (TFs) expression. The results showed that in the most tolerant and susceptible accessions, TaNAC2 and TaNAC69-1 expression levels increased between non-stress and stress conditions significantly, but the increased level of these two genes expression in the most tolerant accession was much higher than the most susceptible accession. According to the obtained results, T. boeoticum can be a suitable and promising gene source for improving modern wheat. In addition, the results of TFs expression could improve our understanding about the complex mechanisms associated with drought tolerance in wheat, especially wild wheat.
One of the stereotactic radiosurgery techniques is Gamma Knife radiosurgery, in which intracranial lesions that are inaccessible or inappropriate for surgery are treated using 201 cobalt-60 sources in one treatment session. In this conformal technique, the penumbra width, which results in out-of-field dose in tumour-adjacent normal tissues should be determined accurately. The aim of this study is to calculate the penumbra widths of single and 201 beams for different collimator sizes of Gamma Knife machine model 4C using EGSnrc/BEAMnrc Monte Carlo simulation code and comparison the results with EBT3 film dosimetry data.
Methods and materials
In this study, simulation of Gamma Knife machine model 4C was performed based on the Monte Carlo codes of EGSnrc/BEAMnrc. To investigate the physical penumbra width (80−20%), the single beam and 201 beams profiles were obtained using EGSnrc/DOSXYZnrc code and EBT3 films located at isocentre point in a spherical Plexiglas head phantom.
Based on the results, the single beam penumbra widths obtained from simulation data for 4, 8, 14 and 18 mm collimator sizes along X axis were 0·75, 0·77, 0·90 and 0·92 mm, respectively. The data for 201 beams obtained from simulation were 2·61, 4·80, 7·92 and 9·81 mm along X axis and 1·31, 1·60, 1·91 and 2·14 mm along Z axis and from film dosimetry were 3·21, 4·90, 8·00 and 10·61 mm along X axis and 1·22, 1·69, 2·01 and 2·25 mm along Z axis, respectively.
The differences between measured and simulated penumbra widths are in an acceptable range. However, for more precise measurement in the penumbra region in which dose gradient is high, Monte Carlo simulation is recommended.
Prior research has typically found a negative relationship between chronic pain and memory, and we examined whether cognitive control processes (e.g. reflection and rumination) moderated this relationship in individuals with Chiari malformation Type I (CM). CM is a neurological condition in which the cerebellar tonsils descend into the medullary and upper cervical spine regions potentially resulting in severe headaches and neck pain.
CM patients who had (n = 341) and had not (n = 297) undergone decompression surgery completed the McGill Pain Questionnaire-Short Form-Revised (SF-MPQ-2), the Rey Auditory Verbal Learning Test (RAVLT), and the Rumination-Reflection Questionnaire (RRQ). Immediate recall scores were compared to those of 102 healthy controls, and delayed recall performance was compared across other variables within the CM group.
CM patients performed more poorly on immediate recall than did controls. Within CM patients, we observed main effects for reflection and age, and a pain x reflection x surgical status (surgery v. no surgery) interaction in which non-decompressed individuals with low levels of pain and high levels of reflection showed superior delayed recall relative to non-decompressed individuals with higher pain and all decompressed individuals.
CM patients show an immediate recall deficit relative to controls, regardless of surgical status. High levels of reflection were associated with better delayed recall performance in non-decompressed CM patients with lower pain levels. High levels of chronic pain may overwhelm increased focused attention abilities, but higher levels of reflection partially overcome the distracting effects of pain and this may represent a type of resilience.
In the limit of a large yield stress, or equivalently at the initiation of motion, viscoplastic flows can develop narrow boundary layers that provide either surfaces of failure between rigid plugs, the lubrication between a plugged flow and a wall or buffers for regions of predominantly plastic deformation. Oldroyd (Proc. Camb. Phil. Soc., vol. 43, 1947, pp. 383–395) presented the first theoretical discussion of these viscoplastic boundary layers, offering an asymptotic reduction of the governing equations and a discussion of some model flow problems. However, the complicated nonlinear form of Oldroyd’s boundary-layer equations has evidently precluded further discussion of them. In the current paper, we revisit Oldroyd’s viscoplastic boundary-layer analysis and his canonical examples of a jet-like intrusion and flow past a thin plate. We also consider flow down channels with either sudden expansions or wavy walls. In all these examples, we verify that viscoplastic boundary layers form as envisioned by Oldroyd. For each example, we extract the dependence of the boundary-layer thickness and flow profiles on the dimensionless yield-stress parameter (Bingham number). We find that, while Oldroyd’s boundary-layer theory applies to free viscoplastic shear layers, it does not apply when the boundary layer is adjacent to a wall, as has been observed previously for two-dimensional flow around circular obstructions. Instead, the boundary-layer thickness scales in a different fashion with the Bingham number, as suggested by classical solutions for plane-parallel flows, lubrication theory and, for flow around a plate, by Piau (J. Non-Newtonian Fluid Mech., vol. 102, 2002, pp. 193–218); we rationalize this second scaling and provide an alternative boundary-layer theory.
We give an asymptotic formula for the minimum number of edges contained in triangles among graphs with n vertices and e edges. Our main tool is a generalization of Zykov's symmetrization method that can be applied to several graphs simultaneously.
Silica aerogels are unique lightweight, nanostructured materials with extremely high porosity (usually above 90%), making them particularly attractive for thermal insulation, although their mechanical fragility still requires strategies of reinforcement that may compromise some of their most appealing properties. The use of silica aerogels still needs to be matured for a broad range of other high-performance applications, and even improved for insulation application. This can be achieved by intensely exploring their surface chemistry versatility, by relying on the enormous variety of silane precursors and chemical routes that can be used. In this work, we present two examples of using reactive moieties in the silane precursors for the preparation of silica aerogels for multipurpose application. In the first case, an acrylate containing silane (3-(trimethoxysilyl)propyl methacrylate) is used along with tetramethyl orthosilicate to produce an organically-modified silica network, which could be reinforced by adding 1,6-bis(trimethoxysilyl)hexane or 1,4-bis(triethoxysilyl)-benzene as spacers and tris[2-(acryloyloxy)ethyl] isocyanurate as cross-linker. These hybrid aerogels have shown an interesting combination of thermal insulation and mechanical properties. Moreover, they could be chemically doped with silica-functionalized magnetite nanoparticles imparting magnetic behaviour to the aerogels but also improving their thermal insulation performance and mechanical strength. Their magnetic feature can be useful for several applications including magnetic separation and drug delivery. As a second example, amine and thiol-functionalized aerogels were used as adsorbents to capture heavy metals from wastewater by complexation, and the preparation of these materials could be accomplished using a combination of silanes, including hydrophobic moieties for a compromise to ensure material stability and good adsorption capacities. Removal percentages of heavy metals reaching 90% were found for metal concentrations of environmental relevance. The amine functionality in aerogels is also useful for other purposes, for example to improve the rate capability of silica aerogels to remove carbon dioxide from gaseous streams or environments.
Background: There is currently little data on the incidence, clinical outcome and management of traumatic interhemispheric subdural hematomas (IHSDHs). Methods: All patients admitted with an acute subdural hematoma (SDH) over a 5-year period at a Level I trauma center were included. A detailed review of all cases of large IHSDH (≥7 mm) was performed to document clinical presentation, management and outcomes. Results: Of 1182 patients with acute subdural hematomas (SDHs), 420 had IHSDHs (24%), and 50 were large IHSDHs. For patients with large IHSDH, the average age was 76 years (±11) and 44% were female. The average GCS was 12 on presentation (±4), and the average GOSE was 4 (±2). 66% of patients had associated cranial/ intracranial injuries (fracture, subarachnoid/epidural/SDH) and 26% required operations for acute convexity SDH. Three patients required operations for their IHSDH by inter hemispheric approach. By 10 weeks, 82% had a complete resolution of the IHSDHs. Conclusions: IHSDHs are often referred to as rare entities. Our results show they are common. Conservative management is often appropriate to manage even large IHSDHs, as most resolve spontaneously. This study will help document the occurrence of falx syndrome, as well as the management and outcomes of larger IHSDHs.