235 research outputs found

    Numerical Solution of Piecewise Constant Delay Systems Based on a Hybrid Framework

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    An efficient numerical scheme for solving delay differential equations with a piecewise constant delay function is developed in this paper. The proposed approach is based on a hybrid of block-pulse functions and Taylor’s polynomials. The operational matrix of delay corresponding to the proposed hybrid functions is introduced. The sparsity of this matrix significantly reduces the computation time and memory requirement. The operational matrices of integration, delay, and product are employed to transform the problem under consideration into a system of algebraic equations. It is shown that the developed approach is also applicable to a special class of nonlinear piecewise constant delay differential equations. Several numerical experiments are examined to verify the validity and applicability of the presented technique

    Alteration of the dopamine receptors� expression in the cerebellum of the lysosomal acid phosphatase 2 mutant (Naked�ataxia (nax)) mouse

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    A spontaneous mutation in the lysosomal acid phosphatase (Acp2) enzyme (nax: Naked� ataxia) in experimental mice results in delayed hair appearance and severe cytoarchitectural impairments of the cerebellum, such as a Purkinje cell (PC) migration defect. In our previous investigation, our team showed that Acp2 expression plans a significant role in cerebellar development. On the other hand, the dopaminergic system is also a player in central nervous system (CNS) development, including cerebellar structure and function. In the current investigation, we have explored how Acp2 can be involved in the regulation of the dopaminergic pathway in the cerebellum via the regulation of dopamine receptor expression and patterning. We provided evidence about the distribution of different dopamine receptors in the developing cerebellum by comparing the expression of dopamine receptors on postnatal days (P) 5 and 17 between nax mice and wild�type (wt) littermates. To this aim, immunohistochemistry and Western blot analysis were conducted using five antibodies against dopamine receptors (DRD1, �2, �3, �4, and �5) accompanied by RNAseq data. Our results revealed that DRD1, �3, and �4 gene expressions significantly increased in nax cerebella but not in wt, while gene expressions of all 5 receptors were evident in PCs of both wt and nax cerebella. DRD3 was strongly expressed in the PCs� somata and cerebellar nuclei neurons at P17 in nax mice, which was comparable to the expression levels in the cerebella of wt littermates. In addition, DRD3 was expressed in scattered cells in a granular layer reminiscent of Golgi cells and was observed in the wt cerebella but not in nax mice. DRD4 was expressed in a subset of PCs and appeared to align with the unique parasagittal stripes pattern. This study contributes to our understanding of alterations in the expression pattern of DRDs in the cerebellum of nax mice in comparison to their wt littermates, and it highlights the role of Acp2 in regulating the dopaminergic system. © 2020 by the authors. Licensee MDPI, Basel, Switzerland

    Biological and reproduction behaviour of Eleuthronema tetradactylum

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    In this study spawning season, brood stocks live place and biological behaviour of Eleutheronema tetradactylum (rashgoo) was identified in the coastal waters of Bushehr province, Persian Gulf from July. 2005 to Sep. 2006. During this time fish samples were collected by the gillnet or set net. With the mesh size of 9 and 25 Cm. A total of 93 fishes were examined in the fishery Research Centre laboratory, Standard length, total weight, gonad and hepatic weight were measured and histological studies on gonads were conducted in this period. Gonadosomatic index was calculated in the different seasons we showed significant differences between research seasons (P<0.05) the Maximum GSI was in winter and spring with (1-1/2 %) and minimum was in summer and autumn (/15-/22 %). In histological study of ovary had observed five stages in sections: IMMATURE, INITIAL MATURATION, ADVANCED MATURATION, MATURED and SPAWNED. And testicular tissues were showed three stages of the sperm development: Spermatogonia, Spermatocytes and Spermatides or sperm. This study had showed that Higher quantities of brood stock were caught in DAYER region of Bushehr province. The stomach contents observed that small fishes, shrimp and crab were feed by the caught fishes, it means that Eleutheronema tetradactylum (rashgoo).is a carnivorous fish. The results were obtained from this research showed that reproductive season in Four finger thread fine (Eleutheronema tetradactylum) (rashgoo) in the coastal waters of Bushehr was in the could seasons

    One-loop Vilkovisky-DeWitt Counterterms for 2D Gravity plus Scalar Field Theory

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    The divergent part of the one-loop off-shell effective action is computed for a single scalar field coupled to the Ricci curvature of 2D gravity (cϕRc \phi R), and self interacting by an arbitrary potential term V(ϕ)V(\phi). The Vilkovisky-DeWitt effective action is used to compute gauge-fixing independent results. In our background field/covariant gauge we find that the Liouville theory is finite on shell. Off-shell, we find a large class of renormalizable potentials which include the Liouville potential. We also find that for backgrounds satisfying R=0R=0, the Liouville theory is finite off shell, as well.Comment: 19 pages, OKHEP 92-00

    Using STROBE checklist to assess the reporting quality of observational studies affiliated with Shiraz University of Medical Sciences, and its correlates: a scientometric study from Iran

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    The reporting quality of Observational Studies (OSs) is an important measure of their overall quality. We aim to assess the reporting quality of OSs of Shiraz University of Medical Sciences (SUMS) in Iran in the years 2012–2015, using Strengthening the Reporting of Observational Studies checklist. Systematic online search was performed. A random sample of SUMS affiliated published articles was selected. Articles were appraised and scored by two reviewers. Variables such as the study design, publication year, journals’ impact factor etc. were retrieved and their correlation with the articles’ scores was assessed. Out of 4297 published articles during 2012–2015, 1742 (40.5%) were OSs of which we assessed 171 (~ 10%) studies. Among these, 87 (50.9%), 74 (43.3%) and 10 (5.8%) articles had a cross-sectional, case–control and cohort design, respectively. Overall score of the reporting quality was 79% ± 0.01. It was at 81% ± 0.1, 77% ± 0.01 and 83% ± 0.02 for cross-sectional, case–control and cohort studies, respectively. A significant correlation was observed between the study design and the score for the reporting quality (P = 0.015). Reporting of “flow-diagram” (5%), “sources of bias” (28%) and “study size calculation” (30%) were the most missed items. Although the overall reporting quality of OSs was found to be at an acceptable rate, there are points of concern regarding some of the most important items that deserve the attention of authors as well as reviewers and editors

    Multiple Locus Variable Number Tandem Repeat Analysis (MLVA) for Typing Pseudomonas Aeruginosa Isolated from Urine Samples of Different Patients

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    BACKGROUND AND OBJECTIVE: Pseudomonas aeruginosa is considered as one of the important causes of urinary infections in hospitals. The aim of the current study is the genetic typing for the number of bacterial strains isolated from patients using MLVA technique. METHODS: In this study, 70 isolates were collected from different hospitals located in Tehran city. First, DNA extraction was conducted for genotyping analysis by MLVA method. Subsequently, VNTR sequences located in several genes of bacterial genomes such as MS-214, MS-215, MS-217, MS-222, MS-223, MS-142 and MS-173 were amplified by specific primers using PCR technique. After confirming the PCR amplification using electrophoresis and visualization of their bonds on agarose gel, relationship evolutionary graph for the different strains was constructed based on MLVA technique. FINDINGS: After the electrophoresis of PCR products and determination of VNTR copy-numbers, 70 strains were classified as 39 types and genetic evolutionary tree was also constructed based on VNTRs Data. According to the MST algorithm, 70 clinical strains divided into 11 clonal complexes which these criteria is interpreted as genetic distance based on the difference of VNTR copy numbers for each group. CONCLUSION: The present study showed that MLVA could be helpful for typing clinical strains of P. aeruginosa. The results also showed that this method had great potential to differentiate those strains with high phenotypic similarity

    Lithium attenuated the depressant and anxiogenic effect of juvenile social stress through mitigating the negative impact of interlukin-1β and nitric oxide on hypothala...

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    Abstract—The neuroimmune-endocrine dysfunction has been accepted as one of fundamental mechanisms contributing to the pathophysiology of psychiatric disorders including depression and anxiety. In this study, we aimed to evaluate the involvement of hypothalamic–pituitary–adre nal (HPA) axis, interleukin-1b, and nitrergic system in mediating the negative behavioral impacts of juvenile social isolation stress (SIS) in male mice. We also investigated the possible protective effects of lithium on behavioral and neurochemical changes in socially isolated animals. Results showed that experiencing 4-weeks of juvenile SIS provoked depressive and anxiety-like behaviors that were associated with hyper responsiveness of HPA axis, upregulation of interleukin-1b, and nitric oxide (NO) overproduction in the pre-frontal cortex and hippocampus. Administration of lithium (10 mg/kg) significantly attenuated the depressant and anxiogenic effects of SIS in behavioral tests. Lithium also restored the negative effects of SIS on cortical and hippocampal interleukin-1b and NO as well as HPA axis deregulation. Unlike the neutralizing effects of L-arginine (NO precursor), administration of L-NAME (3 mg/kg) and aminoguanidine (20 mg/kg) potentiated the positive effects of lithium on the behavioral and neurochemical profile of isolated mice. In conclusion, our results revealed that juvenile SIS-induced behavioral deficits are associated with abnormalities in HPA-immune function. Also, we suggest that alleviating effects of lithium on behavioral profile of isolated mice may be partly mediated by mitigating the negative impact of NO on HPA-immune function. � 2015 IBRO. Published by Elsevier Ltd. All rights reserve

    Universally Coupled Massive Gravity, II: Densitized Tetrad and Cotetrad Theories

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    Einstein's equations in a tetrad formulation are derived from a linear theory in flat spacetime with an asymmetric potential using free field gauge invariance, local Lorentz invariance and universal coupling. The gravitational potential can be either covariant or contravariant and of almost any density weight. These results are adapted to produce universally coupled massive variants of Einstein's equations, yielding two one-parameter families of distinct theories with spin 2 and spin 0. The theories derived, upon fixing the local Lorentz gauge freedom, are seen to be a subset of those found by Ogievetsky and Polubarinov some time ago using a spin limitation principle. In view of the stability question for massive gravities, the proven non-necessity of positive energy for stability in applied mathematics in some contexts is recalled. Massive tetrad gravities permit the mass of the spin 0 to be heavier than that of the spin 2, as well as lighter than or equal to it, and so provide phenomenological flexibility that might be of astrophysical or cosmological use.Comment: 2 figures. Forthcoming in General Relativity and Gravitatio
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