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The paper deals with assortment optimization when customers purchase products using a nonparametric choice model. Each customer is presented with a preference list and will buy an available highest‐ranked offered product on the preference list. The paper presents a novel bi‐objective integer programming model for assortment optimization following a ranking‐based consumer choice model. The objectives are maximizing the expected revenue and maximizing customer satisfaction. This problem is recognized as an NP‐hard problem. After developing the bi‐objective model, an improved version of the augmented ε$\varepsilon $‐constraint method is proposed to solve the problem and retrieve the Pareto‐optimal solutions. In each iteration, this algorithm solves a single‐objective linear integer programming sub‐problem. Our approach aims to obtain a complete set of Pareto‐optimal solutions. Finally, we present computational experiments on synthetic data. Several numerical illustrations are provided at the end to demonstrate the application of the proposed methodology. The computational results provide the decision‐makers with valuable information regarding the factors that mainly affect the solutions. [ABSTRACT FROM AUTHOR]

This article presents an empirical evaluation to investigate the distributional semantic power of abstract, body and full-text, as different text levels, in predicting the semantic similarity using a collection of open access articles from PubMed. The semantic similarity is measured based on two criteria namely, linear MeSH terms intersection and hierarchical MeSH terms distance. As such, a random sample of 200 queries and 20000 documents are selected from a test collection built on CITREC open source code. Sim Pack Java Library is used to calculate the textual and semantic similarities. The nDCG value corresponding to two of the semantic similarity criteria is calculated at three precision points. Finally, the nDCG values are compared by using the Friedman test to determine the power of each text level in predicting the semantic similarity. The results showed the effectiveness of the text in representing the semantic similarity in such a way that texts with maximum textual similarity are also shown to be 77% and 67% semantically similar in terms of linear and hierarchical criteria, respectively. Furthermore, the text length is found to be more effective in representing the hierarchical semantic compared to the linear one. Based on the findings, it is concluded that when the subjects are homogenous in the tree of knowledge, abstracts provide effective semantic capabilities, while in heterogeneous milieus, full-texts processing or knowledge bases is needed to acquire IR effectiveness. [ABSTRACT FROM AUTHOR]

Background: Multiple sclerosis (MS) is the most common neuroinflammatory disease in young adults. Anxiety and depression may predispose individuals to MS and flare-ups. Serotonin transmission is modified in some brain regions of patients with MS, and these changes may contribute to their psychiatric abnormalities. We studied the frequencies of common polymorphisms of the serotonin reuptake transporter (SERT) gene in patients with MS according to their psychological status. Methods: The 5-HTTLPR, rs25531, and STin2VNTR polymorphisms of the SERT gene were genotyped by polymerase chain reaction (PCR)-based methods in 100 patients with MS and 100 healthy controls. Results: There were no remarkable differences in SERT gene polymorphisms between patients with MS and healthy controls. Unlike the control group, 41% of the patients showed some degree of depression based on Beck Depression Inventory (BDI), but no association was observed between SERT gene polymorphisms after the patients were stratified by depression status. Conclusion: In addition to SERT gene polymorphisms, modulation of serotonin at the synapses may also be regulated by genetic variations in tryptophan hydroxylase type 2 and serotonin receptors. Further studies with functional brain imaging of the serotonergic system in patients with MS can provide information on the role of serotonin in this disease. [ABSTRACT FROM AUTHOR]

Semantics and accessibility are naturally part of HTML by design. Therefore, there is a must to significantly leverage the standard markup language and write the cleanest code possible. The purpose of this work is performing HTML validity check in terms of compliance with W3C standards for home pages of Iranian digital and electronic libraries in order to pave way for applying semantic technologies in Iranian Library websites. This is a comparative survey. 82 library software-based digital libraries and 68 electronic libraries were identified via Google search in the domains of .ir, .ac.ir, .org and .com. Data collected via an automatic tool developed by authors in which W3C Markup Validation Service is used for validation tests. Besides, total tags of URLs are counted through it to be able to normalize HTML error frequencies for each home page. Data were analyzed using nonparametric tests via IBM SPSS Statistics 20. Validation test results in about 50 percent failure rate. 38 out of 70 valid libraries are digital libraries and 32 are electronic ones. Mean of HTML error has dramatically decreased in 2017 in comparison with 2015; however Standard Deviation has increased sharply. Moreover, the distribution of HTML error scores is similar across digital and electronic libraries. Regarding conformance to HTML standards, it seems essential to revise the web design of Iranian digital and electronic libraries to fulfill semantic web potentialities. [ABSTRACT FROM AUTHOR]

During the selling time horizon of a product category, a number of products may become unavailable sooner than others and the customers may substitute their desired product with another or leave the system without purchase. So, the recorded sales do not show the actual demand of each product. In this paper, a nonparametric algorithm to estimate true demand using censored data is proposed. A customer choice model is employed to model the demand and then a nonlinear least square method is used to estimate the demand model parameters without assuming any distribution on customer's arrival. A simple heuristic approach is applied to make the objective function convex, making the algorithm perform much faster and guaranteeing the convergence. Simulated dataset of different sizes are used to evaluate the proposed method. The results show a 23% improvement in root mean square error between estimated and simulated true demand, in contrast to alternate methods usually used in practice. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is the most common cause of disability after trauma in young adults in Northern Hemisphere; it imposes a major burden on the affected young people. A significant association between MS and demyelinating peripheral neuropathy which might be due to common pathogenesis for the central and peripheral nerves demyelination has been reported in several studies. We aimed to assess if there is any peripheral nervous system involvement in a sample of Iranian MS population. Extensive nerve conduction studies (NCS) were conducted in 20 MS patients according to McDonald criteria, and 20 age and gender matched healthy appearing controls. The F-wave ratio was calculated through placing the minimum amount of F-wave proximal latency after 10 stimuli and median or tibial nerves compound motor action potential (CMAP) proximal latency in the corresponding formula. Data were compared between groups. Finally, we found the significantly lower median and tibial nerves conduction velocities (NCV) in MS patients than healthy controls (P=0.008 and 0.003 respectively, Independent Samples t-test). Also, tibial NCV had a significant statistical correlation with Kurtzke's expanded disability scale score (EDSS) as patients with higher EDSS had lower tibial NCV (Pearson's correlation coefficient, r²=0.8). No statistical relationship was found between MS subtypes and NCS parameters. Although we found some electrodiagnostic abnormalities in Iranian MS patients in comparison to the healthy participants, these differences were small and inconclusive. More extensive well-designed electrodiagnostic studies for evaluation of peripheral nervous system involvement and its probable pattern in these patients seems to be needed. [ABSTRACT FROM AUTHOR]

The differentiation of vasovagal syncope and epileptic seizure is sometimes problematic, since vasovagal syncope may mimic epileptic seizures in many ways. The present report describes a patient who had been diagnosed and treated as having epilepsy with medically-refractory seizures for 16 years. Often, unlike epileptic seizures, tonic-clonic convulsions and postictal confusion are uncommon features of vasovagal syncope, but these may occur. Our patient was subjected to subcutaneous injection of one ml normal saline, which caused asystole leading to hypoxia and consequently a typical tonic-clonic convulsion. This patient was proved to have vasovagal syncope. The findings in the present case suggest that the possibility of vasovagal syncope should always be taken into consideration when. evaluating patients with medically-refractory or unusual pattern of seizures. In such a circumstance, simultaneous video- electroencephalogram/electocardiogram monitoring may help achieve the correct diagnosis. [ABSTRACT FROM AUTHOR]

This article discusses a study which examined the relationship between month of birth (MOB) and season of birth (SOB) and the risk of multiple sclerosis (MS) in life in an Iranian population. The researchers examined a total of 1,558 patients with a definite MS diagnosis according to McDonald's criteria. They found no significant difference between the cases and controls regarding the time of birth in the different seasons of the year.

A letter to the editor is presented in response to the article related to central nervous system disease multiple sclerosis in Iran in the March, 2014 issue.

Background: World Health Organization declared pandemic phase of human infection with novel influenza A (H1N1) in April 2009. There are very few reports about the neurological complications of H INI virus infection in the literature. Occasionally, these complications are severe and even fatal in some individuals. The aims of this study were to report neurological complaints and/or complications associated with H1N1 virus infection. Methods: The medical files of all patients with H INI influenza infection admitted to a specified hospital in the city of Shiraz, Iran from October through November 2009 were reviewed. More information about the patients were obtained by phone calls to the patients or their care givers. All patients had confirmed H1N1 virus infection with real-time PCR assay. Results: Fifty-five patients with H1N1 infection were studied. Twenty-three patients had neurological signs and/or symptoms. Mild neurological complaints may be reported in up to 42% of patients infected by H1N1 virus. Severe neurological complications occurred in 9% of the patients. The most common neurological manifestations were headache, numbness and paresthesia, drowsiness and coma. One patient had a Guil- lain-Barre syndrome-like illness, and died in a few days. Another patient had focal status epilepticus and encephalopathy. Conclusions: The H1N1 infection seems to have been quite mild with a self-limited course in much of the world, yet there appears to be a subset, which is severely affected. We recommend performing diagnostic tests for H INI influenza virus in all patients r with respiratory illness and neurological signs/symptoms. We also recommend initiating treatment with appropriate antiviral drugs as soon as possible in those with any significant neurological presentation accompanied with respiratory illness and flu-like symptoms. [ABSTRACT FROM AUTHOR]

Background: Hemodynamic depression, including bradycardia and hypotension, is among the most common complications of carotid angioplasty and stenting., Methods and Material: A prospective, cross-sectional study was conducted at Shiraz University of Medical Sciences in southern Iran from 2011 to 2013. Consecutive patients undergoing carotid angioplasty and stenting were included. Demographic data, atherosclerotic risk factors, preprocedural blood pressure, the site of stenosis, the degree of stenosis, and data regarding technical factors were recorded. Hemodynamic depression was defined as a systolic blood pressure less than 90 mmHg and/or heart rate less than 50 beat/min., Results: About 170 patients (67% male, mean age: 71+9.8, 55.9% right side, 82.9% symptomatic) were recruited. Mean degree of stenosis was 79.4% in operated side and 40.7% in nonoperated side. Predilation, postdilation, or both were conducted in 18(10.5%), 141(83%), 11(6.5%) patients respectively. Thirteen (7.6%), 41(24%), and 12(7%) of patients developed postprocedural bradycardia, hypotension or both, respectively. Two patients had a stroke after CAS and periprocedural mortality was 0%. Hemodynamic depression after CAS had a significant association with preprocedure blood pressure and the use of an open cell stent design, but not with atherosclerotic risk factors, site and/or degree of stenosis, predilation, or postdilation. Hemodynamic depression significantly increased hospital stay too., Conclusion: Preprocedural hydration and close-cell stents may decrease the risk of poststenting hemodynamic depression.