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Enhancing the thermal performance of parabolic trough collectors (PTC) is of major interest to maximize solar energy absorption. In common PTCs, solar irradiation is focused on the lower part of the absorber tube which causes high temperatures, thermal stress, and tube deformation. To overcome these problems, it is suggested to rotate the absorber tube with a specified frequency to reduce the high surface temperature and increase the solar energy absorption. In addition, a nanofluid (Al₂O₃-Therminol) is utilized as the heat-carrying fluid. Effects of various parameters, including the rotational speed, absorber tube material, flow rate, and nanoparticles concentration on the collector efficiency were studied. An approximate 2D-transient model of PTC is proposed and a steady-laminar numerical simulation is conducted for the 3D cases. Results indicate that the aluminum is the best choice among the other materials used for the absorber tube, providing about 16 K higher output temperature which is nearly 5% higher than that of the steel. Also, a more uniform surface temperature distribution and a higher collector thermal efficiency could be met. Accordingly, an average increase of 15% in the thermal efficiency of the collector and a maximum decrease of 64 K in the absorber tube temperature are reachable. © 2019 Elsevier Ltd

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The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a destructive pest of tomato that can cause up to 100% yield loss. The predatory bug Nabis pseudoferus (Remane) (Hemiptera: Nabidae) and the parasitoid Trichogramma brassicae (Bezdenko) (Hymenoptera: Trichogrammatidae) are natural enemies of this pest. Since the interaction between predators and parasitoids in different trophic levels including intraguild predation (IGP) can decrease or increase the efficiency of natural enemies, the effects of age-dependent parasitism of host eggs on IGP between these two species were investigated under laboratory conditions. In no-choice and choice preference tests, the predatory bug was exposed to 40 parasitized and nonparasitized eggs of different ages (24, 48, and 72 h old). Investigation of switching behavior was conducted using various combinations of tomato leafminer eggs (30:90, 45:75, 60:60, 75:45, and 90:30 nonparasitized:parasitized eggs) using eggs of different ages (24, 48, and 72 h old). In no-choice tests, the highest feeding rate of the predatory bug was 39.21 ± 0.36 eggs on 24-h-old nonparasitized eggs and the lowest feeding rate was 1.4 ± 0.80 eggs on 72-h-old parasitized eggs. In choice tests, comparison of the Manly's β indices indicated that the predatory bug preferred to feed on nonparasitized eggs with 48- and 72-h-old eggs, but there was no significant preference for the 24-h-old eggs. Results of switching test showed that the linear regression between Manly's β index and different ratios of nonparasitized eggs to parasitized and nonparasitized eggs was not significant in 72-h-old eggs. However, this regression was significant with 24- and 48-h-old eggs and the predator's preference was dependent upon the ratio of nonparasitized and parasitized tomato leafminer eggs. Results of the current study showed that the increasing age of parasitized egg decreased intensity of IGP between N. pseudoferus and T. brassicae.

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Falling is a significant problem in patients with multiple sclerosis (MS) and the majority of falls occur during dynamic activities. Recently, there have been evidences focusing on falls and local stability of walking based on dynamic system theory in the elderly as well as patients with cerebral concussion. However, in patient with MS, this relationship has not been fully investigated. The aim of this study was to investigate local stability of walking as a risk factor for falling in patients with MS.Seventy patients were assessed while walking at their preferred speed on a treadmill under single and dual task conditions. A cognitive task (backward counting) was used to assess the importance of dual tasking to fall risk. Trunk kinematics were collected using a cluster marker over the level of T30 (43%) participants recorded ≥1 falls and were classified as fallers. The results of multiple logistic regression analysis revealed that short-term local dynamic stability in the single task condition (P<0.05, odds ratio=2.214 (1.037-4.726)) was the significant fall predictor.The results may indicate that the assessment of local stability of walking can identify patients who would benefit from gait retraining and fall prevention programs.

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This study involved coating of ostrich meat pieces (30 × 30 × 20 mm) with tragacanth gum (0.25%, 0.5%, and 1%) and salep gum (1%, 2%, and 3%) before osmotic treatment with salt solution (5, 15, and 27%) with the immersing duration of 1, 2, 4, 12, and 24 h to accelerate the transfer of moisture and minimize solid gain. This study also involved the investigation of the efficiency of the Peleg's model, Azuara's model, and diffusion equation in modeling water gain/loss and solid gain in meat pieces. Water gain/loss and solid gain were significantly affected by osmotic and coating concentrations during osmotic treatment. The Peleg's model had the best efficiency in the prediction of water loss at 5% and 27% concentrations and solid gain at 27% concentration. Diffusion model showed a favorable performance in the prediction of water loss and solid gain at 27% and 15% concentrations, respectively. It can be concluded that coating pre-treatment could control solid gain and facilitate water loss/gain.

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Though bivalve mollusks are keystone species and major species groups in aquaculture production worldwide, gamete biology is still largely unknown. This review aims to provide a synthesis of current knowledge in the field of sperm biology, including spermatozoa motility, flagellar beating, and energy metabolism; and to illustrate cellular signaling controlling spermatozoa motility initiation in bivalves. Serotonin (5-HT) induces hyper-motility in spermatozoa via a 5-HT receptor, suggesting a serotoninergic system in the male reproductive tract that might regulate sperm physiology. Acidic pH and high concentration of K

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Neuromyelitis optica spectrum disease (NMOSD) is a chronic inflammatory and usually relapsing demyelinating disease which mainly involves optic nerve and spinal cord and also other parts of the central nervous system. Rituximab has been used for some neurological disorders with a probable autoimmune basis. Early and aggressive immunosuppression therapy is necessary to prevent clinical relapses and permanent disability in NMOSD. Rituximab, a monoclonal antibody against B cells, has been found effective in several recent studies. The objective of this study is to evaluate the clinical efficacy of Rituximab as a newly introduced treatment to NMOSD in Iran.This is an observational cohort study carried out,on 56 patients who have been diagnosed with NMOSD. The patients' information registered in Kashani Hospital MS clinic. They received the first dose of Rituximab for approximately 6 months before the beginning of study. In the first session, every patient was interviewed and examined based on necessary information for the study. Follow up visits were done as needed in a period of 12 months after the first dose. Patient's age, sex, age of onset, presenting symptom, annual relapse rate, acute attacks, EDSS (primary, 6 and 12 months) were recorded. Comparative aims achieved by within group analysis before and after treatment. AntiAQP4 antibody had been checked before the start of study. patients divided into two groups based on the antibody test results for subgroup analysis. Data were analyzed using the IBM SPSS23 - United States software.56 known cases of NMOSD including 17.85% male and 82.15% female were under study. The Mean disease duration was 87.60±59.65 months and mean duration of treatment was 19.56±8.26. The mean EDSS score was primarily 4.83±1.87 and after treatment it decreased significantly (p-value<0.001) to 3.38±1.57 and 2.87±1.63 (6 months and 12 months later). There was a statistical difference between the annual mean relapse rate before and after treatment (p<0.001). The above mentioned index decreased from 1.43±1.107-0.147±0.27. Also, the mean number of attacks in one year before and after treatment were 1.97±0.57 and 0.28±0.45 with significant statistical difference (p<0.001). In the patients with positive anti AQP4 antibody,the mean EDSS decreased from 4.94±1.83-3.52±1.27 and 2.92±1.54. Annual mean relapse rate also decreased significantly from 1.35±0.85-0.10±0.19. Mean number of attacks in one year before and after treatment were 2.05±0.75-0.27±0.46 (p<0.001) respectively.In the current study, we found that Rituximab can significantly improve disability state and also can markedly reduce relapse rate in NMOSD patients.

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Emotion dysregulation is considered as one of the factors related to suicide in individuals with childhood trauma (CT). However, no research has been performed on the role of emotion dysregulation in the relationship between perception of CT and suicidal ideation in individuals who use heroin. This study aimed to evaluate direct and indirect relationships between perception of CT and suicidal ideation through emotion regulation difficulties (ERD) and cognitive emotion regulation strategies (CERSs) in males with a DSM diagnosis of heroin dependence. In a cross-sectional design, 310 males with a DSM diagnosis of heroin dependence completed the Childhood Trauma Questionnaire-Short Form (CTQ-SF), the Difficulties in Emotion Regulation Scale (DERS), the Cognitive Emotion Regulation Questionnaire-Short version (CERQ-Short), the Obsessive-Compulsive Drug Use Scale-Form Heroin (OCDUS-Form Heroin), and the Depression Anxiety Stress Scales (DASS). The results revealed that perception of CT had no direct relation to suicidal ideation. Perception of CT was indirectly associated with suicidal ideation through some ERD dimensions [e.g., non-acceptance of emotional responses (Non-acceptance), limited access to emotion regulation strategies (Strategies), lack of emotional awareness (Awareness)] and the CERS of positive reappraisal. The findings suggest that high suicidal ideation may stem from a perception of CT and subsequently emotion dysregulation in individuals who use heroin. Also, the findings of this research may have implications for the prevention and treatment of suicidal ideation in individuals using heroin with a perception of CT. The results of the present study require further examination through longitudinal studies.

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Twenty-seven samples of infant formulae and follow-on formulae and fifteen samples of baby food from Iranian markets were analyzed for concentrations of four polycyclic aromatic hydrocarbons (PAH4) determined by use of gas chromatography coupled to mass spectrophotometry. An assessment of risks posed to infants and toddlers was conducted by calculating the margin of exposure and incremental lifetime cancer risk (ILCR) by use of the Monte Carlo Simulation Method. Benzo (a) anthracene, was not detected in any of the samples, while approximately 64.3% samples contained detectable amounts of benzo (a) pyrene, while chrysene was observed in three samples and benzo (b) fluoranthene was detected in one sample. One of the samples contained 1.43 μg PAH4/kg, which was greater than the maximum tolerable limit (MTL; 1 μg/kg) stated in Commission Regulation (EU) 2015/1125. Accordingly, the 95% ILCRs in the infants/toddlers due to ingestion of milk powder and baby foods were determined to be 1.3 × 10

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In this study, the possible use of anthocyanins of black carrot (ABC) as a chemo-responsive dye to fabricate a colorimetric pH indicator in a cellulose-chitosan matrix was investigated in order to the monitoring of spoilage in pasteurized milk. Cellulose paper was impregnated with a chitosan solution prepared by a sol-gel method containing ABC (total anthocyanins content of 10 mg/100 mL) and characterized. The swelling and water solubility increased by incorporation of ABC into the chitosan-cellulose film. The colorimetric pH indicator showed an obvious color variation from pink to khaki at different pH values (pH 2-11). Stability tests revealed that the indicator had acceptable color stability during one-month storage at 20 °C. The results also confirmed the immobilization of ABC into the matrix of the polymeric indicator with no significant effect on the chemical and super-molecular structure of the samples. In food trial, fresh pasteurized milk was entirely discerned through a perceptible color change from blue to violet rose color after 48 h storage at 20 °C, which was comfortably observable by the naked eye. The results proved that the fabricated indicator could be used as food grade biomaterials to monitor freshness/spoilage of milk.

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Alzheimer's disease (AD) is the most common neurodegenerative disorder characterized by progressive cognitive decline. According to the critical role of inflammation in pathogenesis of AD and memory deficits, a cytokine with anti-inflammatory properties like interferon beta (IFNβ), currently used to slow down disease progression and protect against cognitive disturbance in multiple sclerosis, might be also an effective treatment in AD condition. This study aimed to answer if the intranasal (IN) administration of IFNβ with high CNS accessibility can alleviate memory impairments in a mutant APP-overexpressing rat model of AD through modulating inflammatory responses. To address this question, the lentiviruses carrying human amyloid protein precursor (APP) with the Swedish and Indiana mutations (LV-APP

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Colorectal cancer (CRC) is one of the most common gastrointestinal malignancies. Despite recent advances in the treatment of CRC, resistance to chemotherapy drugs and recurrence of the tumor are among the main problems for treatment in this cancer. The MTT assay was performed to assess the cytotoxic effects of drugs on CRC cell lines (SW742 and SW480) and normal colon cells. Three-dimensional culture (spheroid) was also used to evaluate the effect of drugs on tumor cell masses. The rate of expression of genes was also evaluated using Real Time PCR. The analysis of the results demonstrated that Aspirin and LGK974 have cytotoxic effects on CRC cell lines, and in the IC50 dose, they disintegrate the cancerous cell masses. These drugs reduce the invasion and increase apoptosis in SW742 and SW480 cell lines. Expression of genes revealed a decrease in the expression of WNT, AXIN, TCF, APC genes and increased expression of β-catenin gene in the WNT signaling pathway. The genes involved in the MAPK signaling pathway such as ERK, JNK, KRAS, MEK showed a decrease in expression and increased expression of RAF gene. In the apoptotic pathway, increased expression of BAX and decreased expression of BCL-2 were reported. Also, decreased expression of P53, Cyclin D1 and COX-2 were observed. This study demonstrates that Aspirin and LGK974 could be effective in inhibiting the signaling pathways of WNT and MAPK, arresting cell cycle, and inducing apoptosis in CRC cell lines. This article is protected by copyright. All rights reserved.

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Male sterility (induced or natural) is a potential tool for commercial hybrid seed production in different crops. Despite numerous endeavors to understand the physiological, hereditary, and molecular cascade of events governing CMS in cotton, the exact biological process controlling sterility and fertility reconstruction remains obscure. During current study, RNA-Seq using Ion Torrent S5 platform is carried out to identify 'molecular portraits' in floral buds among the Cytoplasmic Genic Male Sterility (CGMS) line, its near-isogenic maintainer, and restorer lines. A total of 300, 438 and 455 genes were differentially expressed in CGMS, Maintainer, and Restorer lines respectively. The functional analysis using AgriGo revealed suppression in the pathways involved in biogenesis and metabolism of secondary metabolites which play an important role in pollen and anther maturation. Enrichment analysis showed dearth related to pollen and anther's development in sterile line, including anomalous expression of genes and transcription factors that have a role in the development of the reproductive organ, abnormal cytoskeleton formation, defects in cell wall formation. The current study found aberrant expression of DYT1, AMS and cytochrome P450 genes involved in tapetum formation, pollen development, pollen exine and anther cuticle formation associated to male sterility as well as fertility restoration of CGMS. In the current study, more numbers of DEGs were found on Chromosome D05 and A05 as compared to other chromosomes. Expression pattern analysis of fourteen randomly selected genes using qRT-PCR showed high concurrence with gene expression profile of RNA-Seq analysis accompanied by a strong correlation of 0.82. The present study provides an important support for future studies in identifying interaction between cyto-nuclear molecular portraits, to accelerate functional genomics and molecular breeding related to cytoplasmic male sterility studies in cotton.

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Immune thrombocytopenic purpura (ITP) is a bleeding disorder characterized by low platelet counts in peripheral blood, impairment of thrombopoiesis in bone marrow, and risk of mild to severe bleedings. ITP can be seen among both sexes in different ages. Although definitive pathogenesis of this disorder is still ambiguous, some of risk factors for ITP are recognized, including human leukocyte antigens (HLAs).Our goal was to evaluate the possible association between HLA-B5, 7, 8, 27, and 51 antigens with ITP for the first time. We were hoping to achieve new hypothetical diagnostic/prognostic biomarkers in order to introduce a new subject for further studies on HLA class I antigens as possible risk factors for ITP.A total of 37 patients with ITP were included in this study. After confirmation of ITP diagnosis, peripheral blood samples were collected from them. The expression of each of HLA antigens was evaluated by standard lymphocytotoxicity technique.Compared with other studied antigens, the expression of HLA-B5 and HLA-B51 was more prevalent among our patients. According to the results, 22% of patients were positive for HLA-B5 and HLA-B51. Furthermore, no significant association was found between HLAs expressions with complete blood count parameters.We conclude that there is an association between HLA-B5 and HLA-B51 with ITP and that they are not likely to be used as diagnostic or prognostic biomarkers. We suggest studying the association between HLA-B antigens and ITP in large-scale studies to determine whether or not there is a significant association.

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Risky behaviors are common in developing countries, especially in adolescence. Moreover, sensation seeking is an important factor in personality. This study was conducted to evaluate the relationship between risky behaviors and sensation-seeking in a sample of Iranian adolescents. This study used a cross-sectional method with 400 high school adolescents (age between 15 and 21 years old) in Kashan city from multistage random sampling. The research instrument consisted of three parts: a socio-demographic questionnaire, the Youth Risk Behavior Surveillance System (YRBSS) and the Zuckerman Sensation-Seeking Scale-V (SSS-V). Data analysis was performed using the t-test, ANOVA, chi-square, regression and Spearman correlation coefficient in SPSS v 11.5. Risky behaviors were found in 51.2% of students, and a significant difference was found between the male and female students in this regard (

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A 29-year old woman presented with 2 small and firm subcutaneous nodules on the anterior aspect of the left inferonasal orbital rim. Orbital computed tomography scan showed small well-circumscribed exophytic masses of bone density on frontal process of maxillary bone. The patient refused any surgical intervention in this stage. After 5 years masses demonstrated a significant growth and she requested to do surgery. Complete surgical excision was performed and histopathological diagnosis was consistent with an ivory-typed osteoma. The patient was tumor-free in a 2-year follow up. Orbital osteoma may present as subcutaneous nodules on orbital rim, which can be eradicated by surgical excision of the tumor.

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The chemokine receptor CXCR3 and its ligands CXCL10 and CXCL11 have been suggested to give rise to the most relevant chemokine axis able to facilitate the entrance of immune cells into inflamed tissues and be activated in different inflammatory disorders, such as celiac disease (CD).The aim of this study was to investigate the expression level of CXCR3, CXCL10, and CXCL11 genes in celiac patients compared to healthy controls. Both cohorts have been recruited from the Iranian population.In this case-control study, biopsy specimens were collected from 71 celiac patients (60.5% female) and 90 control subjects (57% female) during 2016. Total RNA was extracted and mRNA expression levels of CXCR3, CXCL10, and CXCL11 genes were investigated by SYBR green qPCR.Based on qPCR and relative quantification method, the mRNA expression levels of CXCR3, CXCL10, and CXCL11 were significantly higher in duodenal biopsies of celiac patients compared to healthy controls in the study population (P = .038, P = .021, and P = .012 respectively).The result of this study showed that CXCR3/CXCL10/CXCL11 signaling axis is overexpressed in the small intestinal mucosa of CD patients compared to controls. This finding might explain the specific enrollment of the main cell populations that infiltrate the epithelium.

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To evaluate the effect of different dressing methods on the wound healing process after pilonidal sinus surgery.In this clinical trial, 60 patients undergoing pilonidal sinus surgery were randomly assigned to one of three groups. In the first group, hydrogel or alginate and hydrocolloid compounds were used as a standard occlusive dressing method. A modified dressing method was used for the second group, in which transparent hydrocolloid films were replaced by Vaseline gauze. The third group was treated using gauze swabs soaked in normal saline. The length and depth of the studied wounds were recorded once a week for a month. During dressing changes, patient pain was recorded using an 11-point numeric rating scale. The collected data were analyzed by descriptive and inferential statistical methods.There was a significant reduction in wound length after 2 weeks in all three groups (P < .05), and the pain experienced by the first and second groups was significantly lower than the third group. However, the modified method used for the second group was associated with a lower cost.Considering the beneficial results of using modern dressings for wound healing and reducing the severity of associated pain, providers may want to consider using modified wound dressings after pilonidal sinus surgery. Study authors recommend that providers receive training on how to use these products.

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To determine the distribution of keratoconus indices in normal children 6 to 12 years of age.This cross-sectional study was conducted in children living in urban and rural areas of Shahroud, northeast Iran in 2015. After careful optometric examinations, the Pentacam was used for corneal imaging and measurement of keratoconus indices.Of 5,620 students who participated in the study, the data of the right eye of 4,947 children were analyzed after applying the exclusion criteria. The mean age of all children was 9.23±1.71 years (range: 6-12 years). The mean and 95% confidence intervals (in the parentheses) of index of surface variance (ISV), index of vertical asymmetry, keratoconus index (KI), central keratoconus index (CKI), index of height asymmetry, index of height decentration (IHD), and average pachymetric progression index (PPIAve) was 17.770 (17.610-17.930), 0.137 (0.135-0.139), 1.022 (1.022-1.023), 1.010 (1.010-1.010), 3.299 (3.230-3.368), 0.007 (0.007-0.008), and 0.948 (0.943-0.952), respectively. The results of multilevel mixed-effects linear regression analysis showed that ISV, KI, CKI, IHD, and PPIAve were significantly higher in girls. Index of surface variance and CKI were higher in urban students, and PPIAve was higher in rural students. Except for PPIAve, which was increased with increasing age, the mean values of other keratoconus indices were significantly lower in 12-year-old students compared with 6-year-old ones.The results provide valuable information about normal distribution of keratoconus indices in children aged 6 to 12 years. These findings can be used in future research and detection of abnormal cases in the clinical setting.

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It has been experimentally proposed that the discrete regions of articular cartilage, along with different subchondral bone tissues, known as the bone-cartilage unit, are biomechanically altered during osteoarthritis degeneration. However, a computational framework capturing all of the dominant changes in the multiphasic parameters has not yet been developed. This article proposes a new finite element model of the bone-cartilage unit by combining several validated, nonlinear, depth-dependent, fibril-reinforced, and swelling models, which can computationally simulate the variations in the dominant parameters during osteoarthritis degeneration by indentation and unconfined compression tests. The mentioned dominant parameters include the proteoglycan depletion, collagen fibrillar softening, permeability, and fluid fraction increase for approximately non-advanced osteoarthritis. The results depict the importance of subchondral bone tissues in fluid distribution within the bone-cartilage units by decreasing the fluid permeation and pressure (up to a maximum of 100 kPa) during osteoarthritis, supporting the notion that subchondral bones might play a role in the pathogenesis of osteoarthritis. Furthermore, the osteoarthritis composition-based studies shed light on the significant biomechanical role of the calcified cartilage, which experienced a maximum change of 70 kPa in stress, together with relative load contributions of articular cartilage constituents during osteoarthritis, in which the osmotic pressure bore around 70% of the loads after degeneration. To conclude, the new insights provided by the results reveal the significance of the multiphasic osteoarthritis simulation and demonstrate the functionality of the proposed bone-cartilage unit model.