1,670 research outputs found

### Initialization Strategy for Nonlinear Systems

The Study Group was asked to provide some hints concerning a choice of initial values to be used for nonlinear algebraic systems. The group has considered the available options and outlined the pros and cons of various methods and provided some recommendations

### A Medical Waste Sterilizer

Sterilization of medical waste is very important for the environment, as the exposition may result in various diseases because of viral or bacterial content of the waste. There are devices developed for this purpose aiming to sterilize the waste in a form called batch process, meaning that a certain amount of waste is placed into the system and subjected to a sterilization procedure for a while and removed from the system afterwards. The procedure is repeated by the next set of waste till the whole set is sterilized. Our aim, however, is to design a device, a rotating cylindrical container having tubular lights attached to the walls inside, through which the waste is exposed to ultraviolet light as it gets rotated and moved towards the exit. The process will continue till the whole set is fed into the system. Such a device would be more effective as compared to batch processing types. The study group is asked to develop a mathematical model to analyse the effect of the number and location of tubes which will lead to maximal exposure during certain amount of time, which also needs an estimate, the sample will reside in the device before it gets discharged

### A Tate cohomology sequence for generalized Burnside rings

Cataloged from PDF version of article.We generalize the fundamental theorem for Burnside rings to the mark morphism of plus constructions defined by Boltje. The main observation is the following: If D is a restriction functor for a finite group G, then the mark morphism Ï : D+ â D+ is the same as the norm map of the Tate cohomology sequence (over conjugation algebra for G) after composing with a suitable isomorphism of D+. As a consequence, we obtain an exact sequence of Mackey functors 0 â over(Ext, Ì)Îł- 1 (Ï, D) â D+ over({long rightwards arrow}, Ï) D+ â over(Ext, Ì)Îł0 (Ï, D) â 0 where Ï denotes the restriction algebra and Îł denotes the conjugation algebra for G. Then, we show how one can calculate these Tate groups explicitly using group cohomology and give some applications to integrality conditions. Â© 2008 Elsevier B.V. All rights reserved

### The effect of vascular graft and human umbilical cord blood-derived CD34+ stem cell on peripheral nerve healing

AIM: There are many trials concerning peripheral nerve damage causes and treatment options. Unfortunately, nerve damage is still a major problem regarding health, social and economic issues. On this study, we used vascular graft and human cord blood derived stem cells to find an alternative treatment solution to this problem. MATERIAL AND METHODS: We used 21 female Wistar rats on our study. They were anesthetized with ketamine and we studied right hind limbs. On Group 1, we did a full layer cut on the right sciatic nerve. On Group 2, we did a full layer cut on the right sciatic nerve, and we covered synthetic vascular graft on cut area. On Group 3, we did a full layer cut on right sciatic nerve, and we covered the area with stem cell applied vascular graft. RESULTS: At the end of postoperative 8. weeks, we performed EMG on the rats. When we compared healthy and degenerated areas as a result of EMG, we found significant amplitude differences between the groups on healthy areas whereas there was no significant difference on degenerated areas between the groups. Then we re-opened the operated area again to reveal the sciatic nerve cut area, and we performed electron microscope evaluation. On the stem cell group, we observed that both the axon and the myelin sheet prevented degeneration. CONCLUSION: This study is a first on using synthetic vascular graft and cord blood derived CD34+ cells in peripheral nerve degeneration. On the tissues that were examined with electron microscope, we observed that CD34+ cells prevented both axonal and myelin sheath degeneration. Nerve tissue showed similar results to the control group, and the damage was minimal. Â© 2018 Ali Yilmaz, Abdullah Topcu, Cagdas Erdogan, Levent Sinan Bir, Barbaros Sahin, Gulcin Abban, Erdal Coskun, Ayca Ozkul

### Oxidative Stress and Mitochondrial Dysfunction in Down's Syndrome: Relevance to Aging and Dementia

Genome-wide gene deregulation and oxidative stress appear to be critical factors determining the high variability of phenotypes in Down's syndrome (DS). Even though individuals with trisomy 21 exhibit a higher survival rate compared to other aneuploidies, most of them die in utero or early during postnatal life. While the survivors are currently predicted to live past 60 years, they suffer higher incidence of age-related conditions including Alzheimer's disease (AD). This paper is centered on the mechanisms by which mitochondrial factors and oxidative stress may orchestrate an adaptive response directed to maintain basic cellular functions and survival in DS. In this context, the timing of therapeutic interventions should be carefully considered for the successful treatment of chronic disorders in the DS population

### Job Analysis System for Civil Engineers in Construction Companies

Job research and analysis studies are the reports that detail the system andenvironmental conditions and performance of each job for obtaining higher efficiency andreducing the unit cost. In order to do the job analysis properly, information and data regardingthe job have to be evaluated accurately and realistically. The originating point of the article isbased on this definition and requirement. In the study, the established job analysis model hasbeen built on system approach. Steps of the model consist of input-preliminary preparation,process-analysis and conclusion phases.In accordance with the model suggested, a job analysis form has been developed to beused in improvement of functions of various human resources and in selection of civil engineersat manager position of construction companies during the study. The form specifies the jobprofile and personal requirements of civil engineers and gives information about time researchstudies aimed at efficiency. Form data has been collected by interviewing 50 (fifty) civilengineers at manager position working at large and medium sized construction firms, in order tobe used in job analysis discipline. In the study, information and data obtained by job analysisform have been analyzed by statistical methods and the results have been compared to similarliterature findings

### Cold Therapy in Migraine Patients: Open-label, Non-controlled, Pilot Study

Some patients with headache report that they have frequently used physical therapies such as application of cold to relieve their headache. There are only a few reported studies related to cold therapies in patients with migraine. In this study, we investigated the effect of cold application on migraine patients. Twenty-eight migraine patients were included. Cold therapy was administered to them by gel cap. Patients used this cap during their two migraine attacks. Before and after the cold therapy, headache severity was recorded by using visual analogue scale (VAS). Patients used this cap for 25 min in each application. They recorded their VAS score just after the therapy and 25 min, 1 h, 2 h and 3 h later. Two patients could not use this therapy due to side effects (one due to cold intolerance and one due to vertigo) in both applications. Therefore, therapeutic efficacy was evaluated in 26 patients. Twenty-five minutes after treatment of the first attack, VAS score was decreased from 7.89 Â± 1.93 to 5.54 Â± 2.96 (P < 0.01). Twenty-five minutes after treatment of the second attack, VAS score was decreased from 7.7 Â± 1.8 to 5.4 Â± 3.55 (P < 0.01). Cold application alone may be effective in some patients suffering from migraine attacks. Its combination with conventional drugs should be investigated in future studies

### Economic burden of ventilator associated pneumonia in a developing country

Ventilator-associated pneumonia (VAP) developed in 96 (60%) of 159 patients with 37.2 cases per 1000 ventilation-days in a medical intensive care unit (MICU). Median time for VAP development was 5.5 days (range: 2-25). The most significant risk factors for VAP were stay in hospital before MICU and length of stay in MICU. The mean length of stay in MICU for VAP patients was 23.8 +/- 19.8 days, which was four-fold higher than for non-VAP patients. The daily cost for VAP patients was half that for non-VAP patients. The total costs for VAP patients were about three-fold higher than for non-VAP patients. (C) 2012 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved

### Infrared renormalons and single meson production in proton-proton collisions

In this article, we investigate the contribution of the higher twist Feynman diagrams to the large-$p_T$ inclusive pion production cross section in proton-proton collisions and present the general formulae for the higher twist differential cross sections in the case of the running coupling and frozen coupling approaches. The structure of infrared renormalon singularities of the higher twist subprocess cross section and the resummed expression (the Borel sum) for it are found. We compared the resummed higher twist cross sections with the ones obtained in the framework of the frozen coupling approximation and leading twist cross section. We obtain, that ratio $R$ for all values of the transverse momentum $p_{T}$ of the pion identical equivalent to ratio $r$. It is shown that the resummed result depends on the choice of the meson wave functions used in calculation. Phenomenological effects of the obtained results are discussed.Comment: 28 pages, 13 figure

### Statistical Theory for Incoherent Light Propagation in Nonlinear Media

A novel statistical approach based on the Wigner transform is proposed for the description of partially incoherent optical wave dynamics in nonlinear media. An evolution equation for the Wigner transform is derived from a nonlinear Schrodinger equation with arbitrary nonlinearity. It is shown that random phase fluctuations of an incoherent plane wave lead to a Landau-like damping effect, which can stabilize the modulational instability. In the limit of the geometrical optics approximation, incoherent, localized, and stationary wave-fields are shown to exist for a wide class of nonlinear media.Comment: 4 pages, REVTeX4. Submitted to Physical Review E. Revised manuscrip
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