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روش‌های فیزیکی و شیمیایی مورد استفاده برای پاک‌سازی آلاینده‎های نفتی، روش‌هایی بسیار دشوار، خطرناک و پرهزینه هستند. ولی بیوتکنولوژی، بسیاری از اوقات راهکارهای موثرتری را برای آلودگی زدایی از محل‌های آلوده فراهم می‌آورد. هدف از این پژوهش، ارزیابی تکنیک زیست فزونی در حذف آلاینده‌های نفتی می‌باشد. در این پژوهش خاک‌های آلوده به گازوییل به مدت 100 روز در ستون‌های مکعب مستطیل به ابعاد m 1×1×1 در دمای محیط و رطوبت نسبی 50% تحت عمل زیست فزونی با میکروب‌ها قرار گرفت و با نمونه خاک آغشته به گازوییل بدون تلقیح میکروبی مقایسه گردید و در نهایت جدایه به‌دست آمده توسط تست‌های بیوشیمیایی و مولکولی شناسایی شد. نتایج شمارش کلی میکروارگانیسم‌ها و آنالیز گاز کروموتوگرافی بیان‌گر این واقعیت است که در مدت 100 روز پس از تلقیح میکروبی ستون‌های خاک مورد نظر، جمعیت میکروبی خاک از 6 10 × 2 به cfu 10 10× 6/2 افزایش داشته است که با توجه به نتایج تست‌های بیوشیمیایی و مولکولی، مشخص شد که در این بین باسیل‌های گرم منفی اکسیداز مثبت (پسودوموناس آئروژینوزا)، جمعیت غالب را تشکیل می‌دهند. آنالیز کیفی و کمی به کمک دستگاه گاز کروموتوگرافی نشان می‌دهد که برخی از اجزاء موجود در نمونه تحت درمان، توسط زیست فزونی از بین رفته یا کاهش یافته‌اند. بررسی‌های انجام شده روی نمونه‌های آغشته به گازوییل توسط دستگاه گاز کروموتوگرافی نشان‌دهنده پاک‌سازی زیستی آلاینده گازوییل توسط میکروب‌های به‌دست آمده از مرحله غربال‌گری می‌باشد.

در این مقاله، یک روش جدید برای حل مسئله تخصیص افزونگی در سیستم‌های سری ـ موازی با اجزای تعمیرپذیر ارائه شده است. در سیستم‌های تعمیرپذیر مفهوم دسترس‌پذیری از اهمیت بسیار بالایی برخوردار است. هدف اصلی این مقاله، بهینه‌سازی دو هدف دسترس‌پذیری و هزینه‌ی سیستم است. با توجه به این که دسترس‌پذیری به دلیل غیرنمایی بودن توزیع نرخ خرابی و تعمیر به صورت ریاضی به سختی قابل برآورد است، برای هر کدام از زیرسیستم‌های دارای اجزای موازی مقدار دسترس‌پذیری با استفاده از شبیه‌سازی جداگانه محاسبه شده و به صورت آرشیو در الگوریتم حل استفاده می‌شود. در این تحقیق، الگوریتم ژنتیک چندهدفه مبتنی بر شبیه‌سازی تبرید برای حل مسئله استفاده می‌شود. الگوریتم ارائه شده بر روی مثال‌های طراحی شده آزمایش شد و بعد از به دست آوردن نتایج از لحاظ آماری با الگوریتم‌های M‌O‌P‌S‌O و N‌S‌G‌A-I‌I مقایسه شدند که برتری S‌A‌M‌O‌G‌A نشان داده شده است.

زمینه و هدف: مطالعات نشان داده اند که کلستروم یا آغوز گاوی دارای خاصیت ضداکسایشی است اما تاکنون مطالعه ای که اثربخشی آن را بر آسیب ورزشی مورد ارزیابی قرار داده باشد یافت نشد. مطالعه حاضر به منظور بررسی اثرات مصرف مکمل آغوز گاوی بر آسیب عضلانی ناشی از ورزش شدید اجرا گردید. روش تحقیق: 48 سر موش صحرایی نر نژاد ویستار به طور تصادفی به شش گروه مساوی تقسیم شدند گروه 1 (کنترل)، گروه 2 (ورزش هوازی)، گروه 3 (ورزش بی هوازی)، گروه 4 (مکمل بدون ورزش)، گروه 5 (مکمل با ورزش هوازی)، گروه 6 (مکمل با ورزش بی هوازی). پس از انجام 1 هفته ای بارگیری مکمل و تمرین، نمونه گیری خون از تمام موش ها انجام و سطح پلاسمایی آنزیم های LDH و CK توسط کیت های استاندارد و دستگاه اتوآنالایز تعیین گردید. داده ها با آزمون های آماری ANOVA و آزمون تعقیبی توکی در سطح 0/05>p تحلیل شد. یافته ها: مقادیر پلاسمایی LDH (p=0/010) و CK (p=0/006) درگروه ورزش بی هوازی به طور معنی داری در مقایسه با گروه کنترل افزایش یافت. اختلاف معنی داری بین گروه ورزش هوازی و گروه کنترل در متغیرهای CK و LDH (p=0/86) وجود نداشت. موش های دریافت کننده مکمل و ورزش بی هوازی شدید (گروه 6) به طور معنی داری سطح CK و LDH کمتری در مقایسه با گروه ورزش بی هوازی بدون مکمل (گروه 3) داشتند (0/001=p)، نتایج نشان داد که بارگیری 7 روزه مکمل آغوز توانست افزایش سطوح CK و LDH ناشی از تمرین بی هوازی را در موش ها مهار نماید. نتیجه گیری: مکمل آغوز با توجه به خواص ضداکسایشی، می تواند به عنوان یک مکمل ورزشی جهت کاهش آسیب های عضلانی استفاده گردد.

Background and Objective: Reaction time measures have considerable potential to aid neuropsychological assessment in a variety of healthcare settings. One such measure, the intra-individual reaction time variability is of particular interest as it is thought to reflect neurobiological disturbance. The present study aimed to investigate the intra-individual changes in reaction time to visual stimuli in dominant or non-dominant binocular and monocular vision. Methods: This descriptive-analytical study was conducted on 12 volunteers with an average age of 30.08±1.448 years in 2021. The subjects consisted of the students and staff of Golestan University of Medical Sciences (5 female and 7 male). The reaction time was recorded automatically by the hand reaction time device of Danesh Salar Iranian Company based on the time of presentation of visual stimulation on the computer screen and the person's reaction, i.e. pressing the buttons of the handles by each of the two hands. All experiments were performed between 10 and 11 am and following at least 2 hours of fasting. Data collection was done following training trials for correct performance of the 2-choice reaction time test. After completing the reaction time tests for each volunteer, the dominant eye was determined by the hole-in-card method. Results: In 4 volunteers, the dominant eye was left and in the rest of the volunteers, the dominant eye was right. The dominant eye did not differ between men and women. The number of reaction times recorded in right monocular vision left monocular vision and binocular vision were 902, 911 and 893, respectively. The mean reaction time in right monocular vision, left monocular vision and binocular vision was 306.81±3.310, 304.28±3.339 and 312.95±4.569, respectively, and the range of reaction times in these three states was between 194-1750, 178-1587, and 155-1797 ms, respectively. Intraindividual reaction time variability in the dominant left eye and left hand were significantly lower compared to the dominant right eye and right hand, respectively (P<0.05). No difference was observed between the reaction time of the right monocular vision, left monocular vision, and binocular vision. Conclusion: The alignment of the dominant left side in the eye and hand reacts faster than the dominant right side in the eye and hand. The mechanism of this phenomenon may be related to the overall process that determines the dominant left hemisphere in approximately 90% of the population. [ABSTRACT FROM AUTHOR]

Objective: Because conservatism in financial statements is applied primarily through the adjustment of accruals, conservative research has largely examined the impact of aspects of this feature on changes in accruals. The role of accruals is primarily to improve cash flow fluctuations. In conservative research based on accruals, typically several economic components of accruals such as sales growth, gross assets, machinery and equipment in the Jones model, and components such as multi-period cash flows in the Dichau and Dicho models Used. Bushman et al. And Allen et al. Improved the two models by combining the above two models. Byzalov and Basu also helped improve these models by breaking down bad news indicators into more detailed components. Therefore, the purpose of this study is to investigate the effect of bad news from other components of company sales, such as product group sales, fourth quarter sales and the company's share of industry, on conditional conservatism in accrual-based models. Methods: To achieve the objectives of this research, data from 144 companies from manufacturing companies listed on the Tehran Stock Exchange for 11 years from 2006 to 2016 using Rahavardnovin software, Kodal site and the site of research, development and Islamic studies of the stock exchange, it was gathered. And the relationships between the research variables were analyzed using panel data and the generalized least squares method. Results: The findings of this study showed that the decrease in sales of the product group and the decrease in sales in the fourth quarter increase conservatism in accruals, because the decrease in these indicators gives signals to the company about the possibility of future sales decline. ; But the decline in the company's share of industry sales has not had a significant effect on the conservative behavior of managers and accountants. Conclusion: In evaluating working capital accruals, managers, in addition to the bad news caused by the decline in the company's overall sales, also pay attention to the analysis of sales decline of each product group in the evaluation of accruals, and if they see a decrease in sales in some product groups, They evaluate their inventory of these products for the next period with more conservatism. Also, if sales are declining for the fourth quarter, it is likely that the decline will continue in the next financial period, resulting in a lack of timely sale of available inventories at the end of the fiscal year, and the company is likely to devalue inventories. On the other hand, it seems that due to the lack of strong competition in the Iranian market and the limited available markets, managers pay more attention to sales changes and do not pay attention to changes in sales share in the industry, as a benchmark and predictive indicator of the future. [ABSTRACT FROM AUTHOR]

Introduction: Breast cancer is the most common type of cancer and the leading cause of cancer death among women. According to estimates in 2018, the most frequency of cancer in Iranian women was related to breast cancer with 13776 (12.5%) new cases. Metastasis is a complication of this disease that occurs in 1%-5% of patients. The aim of this study was to investigate the effect of hormone receptors and Her-2 status on metastasis status in patients with breast cancer using logistic regression. Materials and Methods: In this retrospective study, medical records of 165 breast cancer patients referred to the Ahvaz Shafa Diagnostic and Treatment Center who underwent surgery during 2006-2014 was recorded. Multinomial logistic regression model was applied to identify the related factors to the metastasis status. Results: In the studied patients, 35.2% (58 patients) experienced metastasis. In multinomial logistic model, Her-2 status (P = 0.026) and lymph node involvement (P <0.001) were significant. The odds of metastasis in ER-positive individuals was 2.24 times that of ER-negative individuals (AOR=2.24; CI95%: (0.955-5.275)). Also, the odds of metastasis in patients with lymph node involvement was 5.40 times that of patients without involvement (AOR=5.407; CI95%: (2.180-13.414)). This odds in people with Her-2-positive status was 2.35 times than in those with Her-2-negative status (AOR=0.438; CI95%: (1.109-4.999)). Conclusion: In this study, Her-2-positive status and lymph node involvement were identified as factors associated with metastasis. Early detection of these factors can lead to greater survival of breast cancer patients. [ABSTRACT FROM AUTHOR]

Introduction: Offspring born to preeclamptic mothers are prone to obesity, diabetes, and hypertension in later life, but still, studies investigating the underlying mechanism are still limited. Here, we aimed to investigate the impact of the reduced uteroplacental perfusion (RUPP) rat preeclampsia model on offspring metabolic outcomes. Methods and Materials: Timed pregnant Wistar rats underwent RUPP or sham surgeries on day 14 of gestation. Glucometabolic parameters were evaluated on postnatal days (PND), 14 (childhood), and 60 (young adult). In addition, intraperitoneal glucose tolerance test (IPGTT), homeostatic model assessment of insulin resistance (HOMAIR), immunohistochemical staining for insulin in pancreatic islets, arterial blood pressure and 24-h urine protein (24hUP) excretion were performed at PND60. Results: Male, but not female, young adult rats (PND60) of RUPP dams exhibited an impaired IPGTT, decreased circulatory insulin, and weakened pancreatic insulin immunoreactivity. Compared to the male offspring of the sham group, the body mass of male RUPP offspring significantly caught up after PND42, but it was not sex-specific. RUPP pups also exhibited upregulations in glucagon (only males) and ghrelin (both sexes with a more significant increase in males) during PND14–PND60. However, in sham offspring (both sexes), glucagon levels were downregulated and ghrelin levels were unchanged during PND14–PND60. The blood pressure, HOMA-IR, and 24hUP values did not alter in RUPP pups. Conclusions: The overall results suggest that maternal RUPP has negative and sex-specific impacts on insulin, glucagon, and ghrelin regulations in offspring and that, as young adults, male RUPP rats may be more prone to develop obesity and diabetes. [ABSTRACT FROM AUTHOR]

Background and Objective: Although suction is an important nursing intervention in neonates under ventilation, it can lead to complications such as pain, respiratory distress, hypoxemia, bronchospasm and hospital infection. The purpose of this study was to determine the relationship between pain score and its effective indices in neonatal endotracheal open suction under ventilator in the neonatal intensive care unit of Hamadan hospitals. Materials and Methods: This descriptive correlational study was performed on 120 preterm infants under ventilation in Neonatal intensive care unit of Hamadan hospitals. First, 5 minutes before the patient suction, the respiratory rate and oxygen saturation of the neonatal arterial blood were recorded by the researcher in three shifts based on the findings of the direct monitoring of the infant. During and 5 minutes after suction, the respiratory rate and oxygen saturation index was re-recorded. Data were analyzed using descriptive and regression tests. Results: According on the results of the applied linear regression model, there was a statistically significant relationship between the pressure of the suction device, the duration of suction and the number of suctions with the pain score(P =0.000) but there was no statistically significant relationship between the size of the suction catheter and the pain score (P =0.235). Conclusion: Endotracheal open suction in premature infants can greatly affect the number of respiration and oxygen saturation in the arterial blood and increase the pain score in these infants. [ABSTRACT FROM AUTHOR]

Background and Objective: Parkinson disease (PD) is the second most common neurologic disorder that results following degeneration of dopaminergic neurons in the pars compacta of substintia nigra (SNc). The 1-methyl-1,2,3,6-tetrahydropiridine (MPTP) is a chemical neurotoxin that widely used in animal models of PD. This study was carried out to evaluate the numerical density of dark neurons (DNs) in the SNc in mice subjected to intraperitoneal and intranasal injection of different doses of MPTP. Methods: In this experimental study, 90 male adult BALB/c mice were randomly allocated into four experimental groups including: group 1 (MPTP was injected via i.p. at the dose of 20mg/kg per 2 hours for 4 times), group 2 (MPTP was injected via i.p. at the dose of 30mg/kg for 5 consecutive days), group 3 (MPTP was injected via i.n. at a single dose of 1mg/kg), group 4 (MPTP was injected via i.n. at a single dose of 1mg/kg), four sham and one normal groups. 20 days after the final injection, the animal's brain were removed and stained by toluidine blue. Numerical density of DNs was counted. Results: Intranasal injection of MPTP significantly increased density of dark neurons in the pars compacta of substintia nigra in compare to intraperitoneally injection of MPTP (P<0.05). Conclusion: Intranasal injection of MPTP is more effective manner to induce degeneration of neurons in substintia nigra in animal model of Parkinson's disease. [ABSTRACT FROM AUTHOR]

Background and purpose: The seeds of Astragalus hamosus L. are prescribed for many therapeutic purposes in Traditional Persian Medicine. The present study aimed to investigate the combined effects of metformin and ethanolic extract of Astragalus hamosus L. (AH) on glucose and reproductive parameters in diabetic male rats. Materials and methods: Ethanolic extract of AH was prepared using maceration method. Diabetic male Wistar rats were orally treated with 500 mg/kg metformin (MET500), 150 mg/kg AH, (AH150), 300 mg/kg AH (AH300), and combination of metformin and AH (MET+AH150 and MET+AH300) for 28 consecutive days. Then, fasting blood glucose (FBG), plasma testosterone, sperm quality (count, motility, and viability), testis histopathology, and testicular lipid peroxidation (MDA) were evaluated. Results: Compared with the untreated diabetic group, AH treatment significantly improved testosterone level, sperm count, motility, and viability and decreased testicular MDA (all P<0.01) but it could not change glucose level (P>0.05). AH co-administration with metformin significantly potentiated the beneficial effects of metformin on testosterone (P<0.01) and testicular lipid peroxidation at both doses (P<0.001). While AH co-therapy with metformin at the maximum dose (300 mg/kg) synergistically improved metformin effects on testis morphology (all P<0.05), it could not show a positive combined effect on sperm parameters. Conclusion: AH has no antidiabetic effect and its co-therapy with metformin does not alter the hypoglycemic effect of metformin. However, this combination therapy has a synergistic effect on regulating lipid peroxidation, testosterone level, and testicular histological alterations in diabetic rats. [ABSTRACT FROM AUTHOR]

Background and purpose: Ghrelin, a natural ligand of the growth hormone secretagogue receptor plays a major role in regulation of appetite, body fat mass, and energy balance in the body. The aim of this study was to evaluate the effects of maternal diabetes on circulatory ghrelin levels in rat newborns. Materials and methods: In this experimental study, female Wistar rats were allocated into diabetic (n=20) and control (n=10) groups and mated with males. After parturition, 16 offspring (8 males) were collected at both postnatal days (P), P7 and P14. The body weight, blood glucose and plasma ghrelin levels were measured. Data were analyzed applying two-way ANOVA using sex and group as the factors in SPSS V22. Results: At both P7 and P14, the body weight of newborns of diabetic mothers (18.49± 0.42g, 22.27± 0.43g respectively) were significantly lower (P<0.0001 each) than those of the control group (22.34± 0.402g, 30.32± 1.45g) while there were no significant differences in blood glucose levels between the two groups. At P7, plasma ghrelin levels showed no significant difference between experimental and control groups, but at P14, experimental group had markedly higher ghrelin levels than that of the control group (29.25± 3.59 pg/ml vs. 14.81± 2.75 pg/ml; P<0.0001). Moreover, at P14, male offspring had significantly higher level of ghrelin than female (29.87± 2.58 pg/ml vs. 22.62±1.68 pg/ml; P<0.0001). Conclusion: Current results clearly demonstrate that diabetes during pregnancy can influence plasma ghrelin levels with male and female offspring responding differently. [ABSTRACT FROM AUTHOR]

Background and purpose: Taurine has many biological functions such as antioxidant and antiinflammatory activities and acts as a neurotransmitter. But its effects on the tau phosphorylated protein levels require further studies. The aim of this study was to evaluate the protective and therapeutic effects of taurine on the level of tau phosphorylated protein in the hippocampus of rats treated with scopolamine. Materials and methods: In this research, 72 male Wistar rats were randomly divided into three groups: control, protection, and treatment groups. Protective and therapeutic groups were treated with different doses of taurine (25, 50, 100 mg/kg/day) for 14 days before or after injection of scopolamine (3 mg/kg). After the end of treatment, the extract of homogenized hippocampus tissue was collected to measure the level of tau phosphorylated protein using ELISA technique. Results: Protective injection of different doses of taurine significantly reduced the level of tau phosphorylated protein in the hippocampus compared to that in the protective sham group (p<0.001). Therapeutic injection of taurine at 50 mg/kg significantly decreased the level of tau phosphorylated protein compared with that of the therapeutic sham group. Conclusion: Protective and therapeutic injection of taurine can reduce the tau phosphoryl protein levels in the hippocampus of rats before or after the injection of scopolamine. [ABSTRACT FROM AUTHOR]