409 research outputs found
A Unified Scheme for Modular Invariant Partition Functions of WZW Models
We introuduce a unified method which can be applied to any WZW model at
arbitrary level to search systematically for modular invariant physical
partition functions. Our method is based essentially on modding out a known
theory on group manifold by a discrete group .
We apply our method to with , and to
models, and obtain all the known partition functions and some
new ones, and give explicit expressions for all of them.Comment: 30 page ,SUTDP/11/93/72 Department of Physics, Sharif University of
Technolog
Unusual Behaviour of an Earth-Rockhill Dam
The post-construction behaviour of a 47.5 m high and 700 m long earth-rockfill dam, located in northwestern Iran, is described. The embankment dam is founded on Tertiary rock on both abutments, but in the river channel it rests on alluvial deposits of variable composition and thickness. Since the first impoundment, the dam has undergone large deformations, both in vertical and in horizontal directions. These have resulted in unusual differential settlements, visible along the crest, and have produced wide longitudinal cracks in the asphalt pavement of the crest road. The principle features of the dam are described and selected monitoring results of the crest movements for a sixteen year period are presented. Based on the analysis of the available data and taking into account the geotechnical characteristics of the foundation and the fill materials, an interpretation of the unusual behaviour has been attempted
Antidepressant-like Effect of Extracts From Urtica Dioica in Mice Model of Depression
Urtica dioica (Stinging nettle) leaves have been used as a traditional medicine to treatrheumatoid arthritis, to alleviate rheumatic pain benign prostatic hyperplasia (BPH), diuretic and prevention of kidney stones by local people in Middle East region especially in Iran, Turkey and East Europe. Hence, this investigation evaluates the antidepressant effect of selected crude extracts in the forced swimming test (FST) and tail suspension test (TST), two models predictive of antidepressant activity. The acute treatment of mice with extracts by intra-peritoneal (i.p.) route significantly reduced the immobility time in the FST (50 and 100 mg/kg) and TST (50 and 100 mg/kg), as compared to positive controls (haloperidol and fluoxetine) at 1 and 10 mg/kg, respectively. On the third day of experiment, a significant decrease of mobility was observed for chloroform extract (CE I) and butanol extract (BE II) compared to first day. CE I and BE II led to reduction of immobility time, as the selected extracts with two doses administered were different compared to the control, in the FST method by 65.37% and53.92% for 100 mg/kg, respectively. However, CE I showed the best result compared to our positive controls. Similar results of increased antidepressant effect, that was, of immobility time depending on the concentration administered, were obtained with the TST method. Also our data showed that there was no significant differences between doses (50 and 100 mg/kg). The results suggested that the antidepressant action of the butanol extract and of U. dioica its fraction (BE II2) was mediated by an interaction with 5-hydroxytrptamine (5-HT). U. dioica showed a potential source for the isolation of important natural products with antidepressant-like properties. However, further studies are still require
Composite Zero Valent Iron Nanoparticles And Applications Thereof
In one aspect, composite particles are described herein. A composite particle comprises a substrate, composite metallic or metal oxide nanoparticles supported by the substrate and an amphiphilic or hydrophilic component associated with the substrate, wherein the composite metallic or metal oxide nanoparticles comprise iron and at least one additional transition metal
Composite Zero Valent Iron Nanoparticles And Applications Thereof
In one aspect, composite particles are described herein. A composite particle comprises a substrate, composite metallic or metal oxide nanoparticles supported by the substrate and an amphiphilic or hydrophilic component associated with the substrate, wherein the composite metallic or metal oxide nanoparticles comprise iron and at least one additional transition metal
Beating ratio 0.5 for weighted oblivious matching problems
ESA 2016 is organized in collaboration with the European Association for Theoretical Computer Science (EATCS) and is a part of ALGO 2016We prove the first non-trivial performance ratios strictly above 0.5 for weighted versions of the oblivious matching problem. Even for the unweighted version, since Aronson, Dyer, Frieze, and Suen first proved a non-trivial ratio above 0.5 in the mid-1990s, during the next twenty years several attempts have been made to improve this ratio, until Chan, Chen, Wu and Zhao successfully achieved a significant ratio of 0.523 very recently (SODA 2014). To the best of our knowledge, our work is the first in the literature that considers the node-weighted and edge-weighted versions of the problem in arbitrary graphs (as opposed to bipartite graphs). (1) For arbitrary node weights, we prove that a weighted version of the Ranking algorithm has ratio strictly above 0.5. We have discovered a new structural property of the ranking algorithm: if a node has two unmatched neighbors at the end of algorithm, then it will still be matched even when its rank is demoted to the bottom. This property allows us to form LP constraints for both the node-weighted and the unweighted oblivious matching problems. As a result, we prove that the ratio for the node-weighted case is at least 0.501512. Interestingly via the structural property, we can also improve slightly the ratio for the unweighted case to 0.526823 (from the previous best 0.523166 in SODA 2014). (2) For a bounded number of distinct edge weights, we show that ratio strictly above 0.5 can be achieved by partitioning edges carefully according to the weights, and running the (unweighted) Ranking algorithm on each part. Our analysis is based on a new primal-dual framework known as matching coverage, in which dual feasibility is bypassed. Instead, only dual constraints corresponding to edges in an optimal matching are satisfied. Using this framework we also design and analyze an algorithm for the edge-weighted online bipartite matching problem with free disposal. We prove that for the case of bounded online degrees, the ratio is strictly above 0.5.published_or_final_versio
Chitosan-graphene oxide membranes and process of making the same
This invention relates generally to a chitosan-graphene oxide membrane and process of making the same. The nanocomposite membrane can filter water and remove contaminants without fouling like other commercially-available polymer-based water filters. The membrane can be used as a flat sheet filter or can be engineered in a spiral filtration module. The membrane is scalable and tunable for many water contaminants including pharmaceuticals, pesticides, herbicides, and other organic chemicals. The membrane uses chitosan, which is low-cost, renewable biopolymer typically considered to be a waste product and the second most abundant biopolymer on Earth, thus making the membrane an environmentally-friendly product choice
Chitosan-graphene oxide membranes
This invention relates generally to a chitosan-graphene oxide membrane and process of making the same. The nanocomposite membrane can filter water and remove contaminants without fouling like other commercially-available polymer-based water filters. The membrane can be used as a flat sheet filter or can be engineered in a spiral filtration module. The membrane is scalable and tunable for many water contaminants including pharmaceuticals, pesticides, herbicides, and other organic chemicals. The membrane uses chitosan, which is low-cost, renewable biopolymer typically considered to be a waste product and the second most abundant biopolymer on Earth, thus making the membrane an environmentally-friendly product choice
Developing a comprehensive evidence-based service package for toddlers with autism in a low resource setting: Early detection, early intervention, and care coordination
Objective: The number of children with autism, who have many unmet needs, is increasing dramatically. However, the existing evidence shows that early identification and intervention are effective in reducing the later costs and burdens of autism spectrum disorder (ASD). Thus, the present study aimed to develop evidence-based services for children with autism in Iran to reduce its impacts on the affected children and their families and to decrease its burden on the society. Method: A 3-step study was conducted based on a modification of the Replicating Effective Programs (REP) framework (step 1: need assessment and situation analysis; step 2: identifying current evidence-based services; step 3: designing the first draft of the package and its core elements). Each step was conducted by a specific methodology. Results: By considering the obtained data, it was found that a package of services with 4 core components to respond to the perceived needs in Iran was needed: (1) early detection of at-risk children; (2) care coordination and facilitation of access to current services; (3) implementation of an evidence-based early intervention program; and (4) training interventionists using an effective educational framework based on evidence-based material. Conclusion: REP framework was used in the present study, which has been shown to be effective in adapting and implementing health care services. By considering the preconditions of REP, a comprehensive package of services, with 4 components was designed for toddlers with autism in Iran. The next step will be to study this package using a multicenter hybrid effectiveness-implementation randomized control trial. © 2019 Tehran University of Medical Sciences. All rights reserved
- …