379 research outputs found

    Stochastic Interactions of Two Brownian Hard Spheres in the Presence of Depletants

    Full text link
    A quantitative analysis is presented for the stochastic interactions of a pair of Brownian hard spheres in non-adsorbing polymer solutions. The hard spheres are hypothetically trapped by optical tweezers and allowed for random motion near the trapped positions. The investigation focuses on the long-time correlated Brownian motion. The mobility tensor altered by the polymer depletion effect is computed by the boundary integral method, and the corresponding random displacement is determined by the fluctuation-dissipation theorem. From our computations it follows that the presence of depletion layers around the hard spheres has a significant effect on the hydrodynamic interactions and particle dynamics as compared to pure solvent and pure polymer solution (no depletion) cases. The probability distribution functions of random walks of the two interacting hard spheres that are trapped clearly shifts due to the polymer depletion effect. The results show that the reduction of the viscosity in the depletion layers around the spheres and the entropic force due to the overlapping of depletion zones have a significant influence on the correlated Brownian interactions.Comment: 30 pages, 9 figures, 1 appendix, 40 formulas inside the text, 5 formulas in appendi

    Finite element modeling of electrospun nanofibre mesh using microstructure architecture analysis

    Get PDF
    This investigation is aimed at modeling the tensile behavior of electrospun polyurethane (PU) membrane. The PU web is produced with different morphologies and the structural parameters are studied through SEM images. Three-dimensional network is simulated using ABAQUS software. Each fibre is modeled as hyperelastic material and each crosslink is modeled as multi point constrain tie. The stress-strain behavior of PU mat is modeled by finite element method, and the effect of fibre diameter, fibre orientation and thickness of web is investigated. The stress–strain curves of networks at three different morphologies are compared with modeling measurements. The model by using third order reduced polynominal as fibre hyperelastic potential energy function shows good agreement with experimental findings which confirm that the tensile behavior of PU web can be explained entirely by microstructure of the network

    Behavioral feasibility of the clinical nursing information system

    Get PDF
    Background: Analysis of humanitarian issues affecting the implementation time of information systems to increase the acceptance of these systems is essential. Objective: The aim of this study was to assess the behavioral feasibility of the clinical nursing information system. Methods: An applied cross-sectional study was conducted with 348 nurses in 2015. Data were collected by face to face interviews and a questionnaire containing 33 questions, which were rated on a 5-point Likert scale. Face and content validity of the questionnaire was confirmed, and its reliability was estimated 0.90 through Cronbach's alpha coefficient. Data were analyzed using chi-square tests and t-test. Results: An average score of behavioral feasibility was 67.44. The rate of supply provided for implementing the clinical nursing information system was 55.2, which was in a semi-favorable level. The necessity of system deployment in the clinical nursing sector had the highest frequency (88.2) and interference of redesigning structures with the current work had the lowest frequency (43.6). Conclusion: The possibility of implementation of the clinical nursing information system in a behavioral dimension is at a semi-favorable level. To increase the acceptance of the system, presenting a new system as a positive change and further training of the nurses is recommended. © 2019 Jeddi et al

    A geometric proof of the Lelong-Poincaré formula

    Get PDF
    We propose a geometric proof of the fundamental Lelong-Poincaré formula : ddc log |/ | = [/ = 0] where f is any nonzero holomorphic function defined on a complex analytic manifold V and [/ = 0] is the integration current on the divisor of the zeroes of /. Our approach is based, via the local parametrization theorem, on a precise study of the local geometry of the hypersurface given by /. Our proof extends naturally to the meromorphic case

    Epitope Mapping of Tetanus Toxin by Monoclonal Antibodies: Implication for Immunotherapy and Vaccine Design

    Get PDF
    Tetanus as a life-threatening disease is characterized by muscle spasm. The disease is caused by the neurotoxin of Clostridium tetani. Active form of tetanus neurotoxin is composed of the light chain (fragment A) and the heavy chain. Fragment A is a zinc metalloprotease, which cleaves the neuronal soluble N-ethylmaleimide-sensitive attachment receptor (SNARE) protein, leading to the blockade of inhibitory neurotransmitter release and subsequent generalized muscular spasm. Two functional domains of the heavy chain are fragment C, which is required for neuronal cell binding of the toxin and subsequent endocytosis into the vesicles, and fragment B, which is important for fragment A translocation across the vesicular membrane into the neuronal cytosol. Currently, polyclonal immunoglobulins against tetanus neurotoxin obtained from human plasma of hyper-immunized donors are utilized for passive immunotherapy of tetanus; however, these preparations have many disadvantages including high lot-to-lot heterogeneity, possibility of transmitting microbial agents, and the adverse reactions to the other proteins in the plasma. Neutralizing anti-tetanus neurotoxin monoclonal antibodies (MAbs) lack these drawbacks and could be considered as a suitable alternative for passive immunotherapy of tetanus. In this review, we provide an overview of the literature discussing epitope mapping of the published neutralizing MAbs against tetanus toxin. © 2019, Springer Science+Business Media, LLC, part of Springer Nature

    Pneumothorax complicating isolated clavicle fracture

    Get PDF
    Isolated clavicle fractures are among the commonest of traumatic fractures in the emergency department. Complications of isolated clavicle fractures are rare. Pneumothorax has been described as a complication of a fractured clavicle only rarely in English literature. In all the reported cases, the pneumothorax was treated by a thoracostomy and the clavicle fracture was treated conservatively. In our case, the pneumothorax required a chest drain insertion and the clavicle fracture was treated surgically with good result

    Patients and Public Involvement in Patient Safety and Treatment Process in Hospitals Affiliated to Kashan University of Medical Sciences, Iran, 2013

    Get PDF
    Background: In the recent decades, healthcare providers had a perspective of benevolent paternalism. Nowadays, the patients’ role has changed and they have a significant obligation to participate in their caring decisions. Objectives: The current study aimed to investigate the involvement of patients and public in the patient safety and treatment process in hospitals affiliated to Kashan University of Medical Sciences, Kashan, Iran, 2013. Patients and Methods: A cross-sectional study was conducted in the hospitals affiliated to Kashan University of Medical Sciences in 2013. Subjects included all of the 18 chief managers, 10% of nurses in each hospital, and 375 patients. Data collection instruments included a questionnaire and a checklist designed according to the research objectives. Data analysis was performed using the SPSS ver. 13. Descriptive statistics, percentage and frequencies, were calculated for all variables and analyzed by Chi-square test. Results: In the treatment process, 81 patients (21.61%), 50 nurses (80.6%) and 15 chief managers (83.3%) had awareness about Patient Bill of Rights. In patient Safety, 19.73% of the patients stated that hospitals received their feedbacks. Management activities were weak in evaluation. All of the six hospitals (100%) had a defined process to perform satisfaction surveys’ quality improvement and patient authentication policy. Conclusions: Patient and public participation in Kashan hospitals are not adhered well. As the patient has an important role in improving the quality of services, more use of mass media especially local newspapers, hospital websites, and training programs are suggested to inform both the patients and public on their rights and roles in improving the healthcare services

    The effect of Setarud (IMOD�) on angiogenesis in transplanted human ovarian tissue to nude mice

    Get PDF
    Background: One of the promising methods in fertility preservation among women with cancer is cryopreservation of ovarian cortex but there are many drawbacks such as apoptosis and considerable reduction of follicular density in the transplanted ovary. One solution to reduce ischemic damage is enhancing angiogenesis after transplantation of ovarian cortex tissue. Objective: The aim of this study was to investigate the effect of Setarud, on angiogenesis in transplanted human ovarian tissue. Materials and Methods: In this case control study, twenty four nude mice were implanted subcutaneously, with human ovarian tissues, from four women. The mice were randomly divided into two groups (n=12): the experimental group was treated with Setarud, while control group received only vehicle. Each group was divided into three subgroups (n=4) based on the graft recovery days post transplantation (PT). The transplanted fragments were removed on days 2, 7, and 30 PT and the expression of Angiopoietin-1, Angiopoietin-2, and Vascular endothelial growth factor at both gene and protein levels and vascular density were studied in the grafted ovarian tissues. Results: On the 2nd and 7th day PT, the level of Angiopoietin-1 gene expression in case group was significantly lower than that in control group, while the opposite results were obtained for Angiopoietin-2 and Vascular endothelial growth factor. These results were also confirmed at the protein level. The density of vessels in Setarud group elevated significantly on day 7 PT compared to pre-treatment state. Conclusion: Our results showed that administration of Setarud may stimulates angiogenesis in transplanted human ovarian tissues, although further researches are needed before a clear judgment is made. � 2015, Research and Clinical Center for Infertitlity. All rights reserved

    A review of the personal health records in selected countries and Iran

    Get PDF
    Personal Health Record (PHR) enables patients to access their health information and improves care quality by supporting self-care. The purpose of this study is to provide a comparative analysis of the concept of PHRs in selected countries and Iran in order to investigate the gaps between Iran and more advanced countries in terms of PHRs. The study was carried out in 2008-2009 using a descriptive-comparative method in Australia, the United States, England and Iran. Data was gathered from articles, books, journals and reputed websites in English and Persian published between 1995 and September 2009. After collecting the data, both advantages and disadvantages of each of concepts were analyzed. In the three countries considered in the present study the concepts of PHR, extracted from the literature, are that; a)patient/person be recognized as the owner of PHR; b)information be disclosed only to those authorized by the patient; c) and that PHR is created upon request and consent of the individual involved. Before PHRs can be profitably used in the health administration of a (developing) country, the necessary knowledge, infrastructures, and rules need to be developed. © Springer Science+Business Media, LLC 2010

    Effects of Chlamydia trachomatis Infection on Fertility; A Case-Control Study.

    Get PDF
    BACKGROUND: Nowadays, Chlamydia trachomatis is known as a causative agent of infertility. Because of, asymptomatic nature of infection, many may suffer from its lasting complications such as infertility. This study was performed in Tehran during April 2007 to April 2008 to compare the prevalence of Chlamydia trachomatis infection in fertile and infertile women using ELISA and PCR methods. METHODS: Overall, 234 infertile and 223 pregnant women, as the fertile group, participated in this hospital-based case-control study. After completing an informed consent form and the questionnaire, first catch urine and blood sample were obtained for PCR and ELISA (IgG, IgM) tests, respectively. Logistic regression analysis was used to control possible confounding factors, and determine adjusted odds ratio of infertility due to the infection. RESULTS: PCR results revealed that 29 (12.4%) of the infertile and 19 (8.5%) of the fertile women were positive for C. trachomatis infection (p = 0.440). IgG was positive in 21 (9.0%) of the infertile and 11 (5.0%) in the fertile group (p = 0.093). IgM assays identified that 2 (0.9%) of the infertile and 4 (1.8%) of the fertile women were positive for the micro-organism (p = 0.375). CONCLUSION: We found no significant differences among fertile and infertile women for Chlamydia trachomatis infection. Nevertheless, molecular techniques which are more sensitive, more specific and non-invasive can be used to detect C. trachomatis infection
    corecore