An Efficient Streaming Algorithm for the Submodular Cover Problem

We initiate the study of the classical Submodular Cover (SC) problem in the data streaming model which we refer to as the Streaming Submodular Cover (SSC). We show that any single pass streaming algorithm using sublinear memory in the size of the stream will fail to provide any non-trivial approximation guarantees for SSC. Hence, we consider a relaxed version of SSC, where we only seek to find a partial cover. We design the first Efficient bicriteria Submodular Cover Streaming (ESC-Streaming) algorithm for this problem, and provide theoretical guarantees for its performance supported by numerical evidence. Our algorithm finds solutions that are competitive with the near-optimal offline greedy algorithm despite requiring only a single pass over the data stream. In our numerical experiments, we evaluate the performance of ESC-Streaming on active set selection and large-scale graph cover problems.Comment: To appear in NIPS'1

Comparison of Activated Charcoal and Industrial Charcoal in Prevention of GI Absorption of Diazepam

BBackground: GI decontamination is required frequently in management of intoxicated patients. Activated charcoal is used for this purpose normally. Is it possible that powdered industrial charcoal is used as a substitute? Present study was conducted to determine efficiency of industrial charcoal in prevention of absorption of diazepam, compared to activated charcoal. Method: 30 Sprague–dawley rats were randomly divided into 3 equal groups. 20 mg/kg diazepam was given orally to all 3 groups. No GI decontamination was performed for the control group. Activated and industrial charcoal (1 g/kg dissolved in 10 ml of water) was administered for other two groups. The urinary concentration of diazepam was used for evaluation of level of the drug absorption in the animals. Results: The mean urine concentration of diazepam was considerably lower in groups taking charcoal, compared control group. However the concentration in the group taking activated charcoal was lower than the concentration in the group taking industrial charcoal. Conclusion: Results of present study suggest that industrial charcoal can be used as a substitute for activated charcoal, though with a little lower efficacy for absorption of drugs and toxins

Incidence of Dentinal Crack Formation Using ProTaper Universal and WaveOne Systems in Straight and Curved Root Canals

Introduction: This study aimed to compare dentinal micro crack formation following root canal instrumentation with ProTaper Universal (PTU) and WaveOne (WO) rotary systems in straight and curved root canals. Methods and Materials: One hundred mesiobuccal (MB) straight and curved canals of mandibular molars meeting inclusion criteria were divided into two control (n=10) and four experimental groups (n=20). After mounting the teeth and simulating the periodontal ligament, all the MB canals were coronally flared using Gates-Glidden drills #3 and 2 respectively. Then, in the experimental groups, the canals were instrumented with either PTU files (Sx, S1, S2, F1, F2), or Primary WO (25/0.08). Afterwards, roots were horizontally sectioned at 2, 4, and 6 mm from the apices, and evaluated under a microscope under 20× magnification. Data were analyzed with the Chi-Square and Kruskal-Wallis tests. The significance level was set at 0.05. Results: The control groups showed no cracks. There was no significant difference between the two systems in the straight root canals (P>0.05). But in the curved root canals, PTU produced significantly more cracks (P<0.05) with the complete crack type which was dominant (P=0.013) compared to WO. Conclusions: This in vitro study showed that in curved root canals, instrumentation with reciprocal WO system may be safer than full rotational PTU instruments regarding crack formation.Keywords: Crack; Dentin; Instrumentation; Reciprocating; Root Canal Preparation

Replacement of fish oil with canola vegetable oil-based diets on growth and survival rate of Caspian trout, Salmo caspius fry

This study was conducted to evaluate the effects of different levels of canola oil on growth performance and survival rate of Caspian trout (Salmo caspius) fry during replacement with canola oil over a period of 60 days. 180 pieces of fish fry (4.6 ± 0.23 g in weight) with a density of 15 individuals were placed in 300-liter fiberglass tanks. Four treatments each with 3 replicates were fed with diets including 100% fish oil (T1), 100% canola oil (T2), 50% fish oil and 50% canola oil (T3), 70% fish oil and 30% canola oil (T4) with the same protein and fat levels of 43% and 14%, respectively. The results showed that the highest weight (26.46 g), final length (13.46 cm) and specific growth rate (2.97%/day) belonged to T3 exhibiting a significant difference with other treatments (p≤0.05). Moreover, the lowest value of feed conversion ratio (1.41) and the highest amount of condition factor (1.17 ± 0.08) were also found in T3. However, these differences were not statistically significant (p>0.05). The highest protein efficiency coefficient of 2.37 was found in T4, exhibiting a significant difference with other treatments (p≤0.05). The survival rate among all treatments was 100% (with no mortality). Based on the results, it can be concluded that the partialy replacement of fish oil with canola oil (50% fish oil with 50% canola oil) in the diet of Caspian trout not only has no negative impact on growth indices and survival rate, but also can enhance these indices and decrease costs by reducing the length of the culture period

Involvement of nitric oxide in granisetron improving effect on scopolamine-induced memory impairment in mice

AbstractGranisetron, a serotonin 5-HT3 receptor antagonist, widely used as an antiemetic drug following chemotherapy, has been found to improve learning and memory. In this study, effects of granisetron on spatial recognition memory and fear memory and the involvement of nitric oxide (NO) have been determined in a Y-maze and passive avoidance test. Granisetron (3, 10mg/kg, intraperitoneally) was administered to scopolamine-induced memory-impaired mice prior to acquisition, consolidation and retrieval phases, either in the presence or in the absence of a non-specific NO synthase inhibitor, l-NAME (3, 10mg/kg, intraperitoneally); a specific inducible NO synthase (iNOS) inhibitor, aminoguanidine (100mg/kg); and a NO precursor, l-arginine (750mg/kg). It is demonstrated that granisetron improved memory acquisition in a dose-dependent manner, but it was ineffective on consolidation and retrieval phases of memory. The beneficial effect of granisetron (10mg/kg) on memory acquisition was significantly reversed by l-NAME (10mg/kg) and aminoguanidine (100mg/kg); however, l-arginine (750mg/kg) did not potentiate the effect of sub-effective dose of granisetron (3mg/kg) in memory acquisition phase. It is concluded that nitric oxide is probably involved in improvement of memory acquisition by granisetron in both spatial recognition memory and fear memory.This article is part of a Special Issue entitled The Cognitive Neuroscience

Effect of general health status on chronicity of low back pain in industrial workers

Recognizing patients at a higher risk of developing chronic low back pain (LBP) is important in industrial medicine. This study aimed to assess the power and quality of General Health Questionnaire (GHQ) for prediction of the odds of chronicity of acute LBP. This study was conducted on industrial workers. All subjects with acute LBP who met the inclusion criteria were enrolled. Demographic characteristics, occupational, physical, and mental parameters and the general health status of subjects were evaluated; they were followed up for developing chronic LBP for one year. Cigarette smoking, high body mass index, job stress, physical load and high GHQ scores were found to be the risk factors for the progression of acute LBP to chronic LBP (P0.05). High GHQ score can be a risk factor for progression of acute LBP to chronic LBP. The GHQ in combination with the Job Content Questionnaire can be used as a quick and simple screening tool for detection of subjects at high risk of chronic LBP when evaluating acute LBP in an occupational setting. © 2016 Tehran University of Medical Sciences. All rights reserved.

Effects of Combining Methylprednisolone with Magnesium Sulfate on Neuropathic Pain and Functional Recovery Following Spinal Cord Injury in Male Rats

Methylprednisolone (MP) has been widely used as a standard therapeutic agent for the treatment of spinal cord injury (SCI). Because of its controversial useful effects, the combination of MP and other pharmacological agents to enhance neuroprotective effects is desirable. Magnesium sulfate (MgSO4) has been shown to have neuroprotective and antihyperalgesic effects. In the present study, we sought to determine the effect of combining MP and MgSO4, on neuropathic pain and functional recovery following spinal cord injury (SCI) in male rats. A total of 48 adult male rats (weight 300-350 g) were used. After laminectomy, complete SCI was achieved by compression of the spinal cord for one minute with aneurysm clips. Single doses of Magnesium sulfate (MgSO4), (600 mg/kg), Methylprednisolone (MP), (30 mg/kg) or combining MgSO4 and MP were injected intraperitoneally. Prior to surgery and during four weeks of study Tail flick latency (TFL) and BBB (Basso-Beattie-Bresnahan) score and the acetone drop test were evaluated. In mean values of BBB score, a significant difference was observed in SCI+veh compared with other groups (P<0.05). Mean TFL also was significantly higher in SCI+veh compared with other groups (P<0.05). Mean acetone drop test score and weight were significantly different in MgSO4, MP and combining MgSO4 and MP  treated groups compared with SCI+veh group (P<0.05). These findings revealed that MP, MgSO4 and combining MgSO4 and MP treatment can attenuate neuropathic pains following SCI in rats include: thermal hyperalgesia and cold allodynia. They also can yield better improvement in motor function and decrease weight loss after SCI in rats compared with the control group

Pharmacological Profile for the Contribution of NO/cGMP Pathway on Chlorpheniramine Antidepressant-Like Effect in Mice Forced Swim Test

Chlorpheniramine, a first-generation antihistamine, is widely used for allergic reactions. Previous studies showed the interaction between antidepressant activity and nitric oxide and cyclic guanosine monophosphate (NO/cGMP) pathway. Thus, we aimed to assess the possible involvement of NO/cGMP pathway in this effect using forced swim test (FST) in male mice. To evaluate the locomotor activity and immobility time, we performed open field test (OFT) and FST on each mouse. Chlorpheniramine was administered intraperitoneally (i.p.) (0.1, 0.3, 1, 10 mg/kg) 30 minutes before FST. To assess the involvement of NO/cGMP pathway, a non-selective nitric oxide synthase (NOS) inhibitor, L-NAME (10mg/kg, i.p.), a selective inducible NOS (iNOS) inhibitor, aminoguanidine (50 mg/kg, i.p.), a selective neural NOS (nNOS) inhibitor, 7-nitroindazole (7-NI, 30 mg/kg, i.p.), a NO precursor, L-arginine (750 mg/kg, i.p.) and a selective phosphodiesterase-5 (PDE-5) inhibitor, sildenafil (5 mg/kg, i.p.) was co-administered with chlorpheniramine. Chlorpheniramine significantly decreased the immobility time at doses of 1mg/kg (P0.05). Moreover, pretreatment with L-arginine (P<0.01) and sildenafil (P<0.001) significantly reduced the anti-immobility effect of chlorpheniramine. These treatments did not alter the locomotor activity of mice in OFT. Our results revealed that the antidepressant-like effect of chlorpheniramine is mediated through inhibition of NO/cGMP pathway

Pattern design for web-based tutoring based on attendance factor

تا به امروز آموزش مبتنی بر وب روند رو به رشدی را طی نموده است. تعداد بی‌شماری از دوره‌های آموزش مبتنی بر وب توسط مؤسسات آموزشی در سرتاسر دنیا ارائه شده است. برغم افزایش چشم‌گیر دوره‌های مبتنی بر وب و فراگیرانی که در این دوره‌ها ثبت‌نام می‌کنند،  نشانه‌های زیادی مبنی بر اینکه دوره‌های فوق در برآورده سازی نیازهای فراگیران ناموفق بوده و فراگیران تجارب ناموفقی را از چنین دوره‌هایی به یاد دارند،  به چشم می‌خورد. در این بین نتایج بسیاری از تحقیقات نشان می‌دهد عامل حضور، عامل مهمی در پیشرفت و موثر بودن همه آموزش‌ها از جمله آموزش‌های سنتی و از راه دور بوده و همبستگی بالایی با پیشرفت تحصیلی و رضایت فراگیران دارد. بر این اساس، پژوهش حاضر باهدف طراحی الگویی برای آموزش‌های مبتنی بر وب بر اساس عامل حضور انجام شد. روش تحقیق مورد استفاده در این مطالعه، تحلیل محتوای کیفی از نوع قیاسی بود جامعه پژوهش، شامل کلیه منابع و مقالات مرتبط نمایه شده در پایگاه‌های اطلاعاتی پروکوئیست، اسپرینگر، ساینسدایرکت، امرالد، ابسکو، سیج، اریک، و گوگل اسکولار بود. نمونه‌برداری از این منابع با روش نمونه‌گیری هدفمند انجام گرفت، 39 مقاله و کتاب مطابق معیارهای مورد نظر بررسی شد و داده‌های حاصله برای تشکیل چهارچوب پیشنهادی تلفیق گردید