404 research outputs found

    Nonlinear wave interaction and spin models in the MHD regime

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    Here we consider the influence on the electron spin in the MHD regime. Recently developed models which include spin-velocity correlations are taken as a starting point. A theoretical argument is presented, suggesting that in the MHD regime a single fluid electron model with spin correlations is equivalent to a model with spin-up and spin-down electrons constituting different fluids, but where the spin-velocity correlations are omitted. Three wave interaction of 2 shear Alfven waves and a compressional Alfven wave is then taken as a model problem to evaluate the asserted equivalence. The theoretical argument turns out to be supported, as the predictions of the two models agree completely. Furthermore, the three wave coupling coefficients obey the Manley-Rowe relations, which give further support to the soundness of the models and the validity of the assumptions made in the derivation. Finally we point out that the proposed two-fluid model can be incorporated in standard Particle-In-Cell schemes with only minor modifications.Comment: 8 page

    Fluid moment hierarchy equations derived from gauge invariant quantum kinetic theory

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    The gauge invariant electromagnetic Wigner equation is taken as the basis for a fluid-like system describing quantum plasmas, derived from the moments of the gauge invariant Wigner function. The use of the standard, gauge dependent Wigner function is shown to produce inconsistencies, if a direct correspondence principle is applied. The propagation of linear transverse waves is considered and shown to be in agreement with the kinetic theory in the long wavelength approximation, provided an adequate closure is chosen for the macroscopic equations. A general recipe to solve the closure problem is suggested.Comment: 12 pages, 1 figur

    Morphine Suppository versus Indomethacin Suppository in the Management of Renal Colic: Randomized Clinical Trial

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    Background. Renal colic is a medical emergency due to the rapid onset and devastating nature of its pain. Opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) are both used as first-line choices in its management. Aim. This study aimed to compare the efficacy and safety of opioids and NSAIDs in the management of acute renal colic. Methods. One hundred and fifty-eight patients were divided into two groups (n=79) and received either 10 mg morphine or 100 mg indomethacin suppositories. The severity of pain was measured using verbal numeric rating scale at baseline and 20, 40, 60, and 90 minutes after the administration of analgesics. Drug side effects as well as patients' vital signs were also recorded. Results. The mean decrease in the pain score during the first 20 minutes was significantly higher among those who received morphine suppository. However, no significant difference was observed between the two groups regarding the mean decrease in pain score during the first 40, 60, and 90 minutes after the admission. Prevalence of drug side effects or changes in the vital signs was not significantly different between the two groups. Conclusions. Morphine suppositories seem to be more efficient in achieving rapid pain relief comparing to indomethacin. © 2016 Forough Zamanian et al

    Fluid moment hierarchy equations derived from quantum kinetic theory

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    A set of quantum hydrodynamic equations are derived from the moments of the electrostatic mean-field Wigner kinetic equation. No assumptions are made on the particular local equilibrium or on the statistical ensemble wave functions. Quantum diffraction effects appear explicitly only in the transport equation for the heat flux triad, which is the third-order moment of the Wigner pseudo-distribution. The general linear dispersion relation is derived, from which a quantum modified Bohm-Gross relation is recovered in the long wave-length limit. Nonlinear, traveling wave solutions are numerically found in the one-dimensional case. The results shed light on the relation between quantum kinetic theory, the Bohm-de Broglie-Madelung eikonal approach, and quantum fluid transport around given equilibrium distribution functions.Comment: 5 pages, three figures, uses elsarticle.cl

    Spin and magnetization effects in plasmas

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    We give a short review of a number of different models for treating magnetization effects in plasmas. In particular, the transition between kinetic models and fluid models is discussed. We also give examples of applications of such theories. Some future aspects are discussed.Comment: 18 pages, 1 figure. To appear in Plasma Physics and Controlled Fusion, Special Issue for the 37th ICPP, Santiago, Chil

    Exploring conserved mRNA-miRNA interactions in colon and lung cancers

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    Aim: The main goal of this analysis was prioritization of co-expressed genes and miRNAs that are thought to have important influences in the pathogenesis of colon and lung cancers. Background: MicroRNAs (miRNAs) as small and endogenous noncoding RNAs which regulate gene expression by repressing mRNA translation or decreasing stability of mRNAs; they have proven pivotal roles in different types of cancers. Accumulating evidence indicates the role of miRNAs in a wide range of biological processes from oncogenesis and tumor suppressors to contribution to tumor progression. Colon and lung cancers are frequently encountered challenging types of cancers; therefore, exploring trade-off among underlying biological units such as miRNA with mRNAs will probably lead to identification of promising biomarkers involved in these malignancies. Methods: Colon cancer and lung cancer expression data were downloaded from Firehose and TCGA databases and varied genes extracted by DCGL software were subjected to build two gene regulatory networks by parmigene R package. Afterwards, a network-driven integrative analysis was performed to explore prognosticates genes, miRNAs and underlying pathways. Results: A total of 192 differentially expressed miRNAs and their target genes within gene regulatory networks were derived by ARACNE algorithm. BTF3, TP53, MYC, CALR, NEM2, miR-29b-3p and miR-145 were identified as bottleneck nodes and enriched via biological gene ontology (GO) terms and pathways chiefly in biosynthesis and signaling pathways by further screening. Conclusion: Our study uncovered correlated alterations in gene expression that may relate with colon and lung cancers and highlighted the potent common biomarker candidates for the two diseases

    Differences in and correlates of sexual function in infertile women with and without polycystic ovary syndrome

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    Background: The aim of this study was to examine sexual function and its correlates among infertile women with polycystic ovary syndrome (PCOS) in comparison with their non-PCOS counterparts. Materials and Methods: In this case-control study, 209 infertile women (116 PCOS and 93 non-PCOS) from Tehran, Iran, were evaluated in February and March 2018. Female sexual function index (FSFI), hormonal status, and documented reports of hyperandrogenic manifestations of the patients were investigated. Results: The mean age of the patients was 32.00 ± 5.00 years old. Eighty-four (40.2) patients including 42.2 of the PCOS patients and 37.6 of the non-PCOS cases (P>0.05), were suspected of female sexual dysfunction (FSD). The most impaired functions in both groups were desire and arousal. Sexual function was not significantly different between the groups. However, PCOS women had more orgasm problems and acne worsened their sexual function. Total FSFI was positively associated with prolactin level but negatively associated with central obesity in the non-PCOS group; it was negatively correlated with marital duration in the PCOS group. Luteinizing hormone (LH) and pain, prolactin level and lubrication, and central obesity and arousal were correlated in the non-PCOS women. Prolactin level and orgasm, marital duration and arousal, and marital duration and the total FSFI were correlated in the PCOS women. Conclusion: Sexual function was similarly low in infertile PCOS and non-PCOS women. However, orgasm problems and the negative effect of acne varied between the two groups. Further investigations may target how hormonal profile may affect sexual function. Practitioners should scrutinize the specific impaired sexual domains and their correlated conditions in PCOS women, notably orgasm, acne, and prolactin level. Interventions should be well tailored based on particular needs of infertile PCOS women. © 2021, Royan Institute (ACECR). All rights reserved

    Protein interaction mapping related to to becker muscular dystrophy

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    Objective Becker Muscular Dystrophy (BMD) is a neuromuscular disorder which is incurable. In this research protein interaction network of most associated proteins with BMD to provide better clarification of disorder underlying mechanism was investigated. Materials & Methods The related genes to BMD were retrieved via string database and conducted by Cytoscape and the related algorithms. The network centrality analysis was performed based on degree, betweenness, closeness, and stress parameters. Gene ontology and clustering were performed via ClueGO analysis. Results DMD as the super-hub as well as other central proteins including UTRN, TTN, DNM2, and RYR1 are important in BMD in terms of interactive features. The impairment of muscular contraction may be vital in BMD disease pathogenesis as it is the highlighted biological process term obtained by ClueGO analysis. Conclusion DMD targeting may be the main concern for dystrophy clinical approaches. However, the other suggested proteins should be evaluated. Targeting these key proteins are required for treatment goals following extensive validation studies. © 2019, Iranian Child Neurology Society. All rights reserved

    Severe pulmonary arterial hypertension is characterized by increased neutrophil elastase and relative elafin deficiency

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    BACKGROUND: Preclinical evidence implicates neutrophil elastase (NE) in PAH pathogenesis, and the NE inhibitor elafin is under early therapeutic investigation. RESEARCH QUESTION: Are circulating NE and elafin levels abnormal in PAH and associated with clinical severity? STUDY DESIGN/METHODS: . In an observational Stanford University PAH cohort (N=249), plasma NE and elafin were measured in comparison to healthy controls (N=106) then related to clinical features and relevant ancillary biomarkers. Cox regression models were fitted with cubic spline functions to associate NE and elafin with survival. To validate prognostic relationships, we analyzed two United Kingdom cohorts (N=75, N=357). Mixed effects models evaluated NE and elafin changes during disease progression. Finally, we studied effects of NE/elafin balance on pulmonary artery endothelial cells (PAECs) from PAH patients. RESULTS: Relative to controls, patients had increased NE (205.1 [123.6-387.3] vs. 97.6 [74.4-126.6] ng/mL, P168.5 ng/mL portended increased mortality risk after adjustment for known clinical predictors (HR 2.52, CI 1.36-4.65, P=0.003) or prognostic cytokines (HR 2.63, CI 1.42-4.87, P=0.001), and NE added incremental value to established PAH risk scores. Similar prognostic thresholds were identified in validation cohorts. Longitudinal NE changes tracked with clinical trends and outcomes. PAH-PAECs exhibited increased apoptosis and attenuated angiogenesis when exposed to NE at the level observed in patients' blood. Elafin rescued PAEC homeostasis, yet the required dose exceeded levels found in patients. INTERPRETATION: NE is increased and elafin deficient across PAH subtypes. NE associates with disease severity and outcomes, and this target-specific biomarker could facilitate therapeutic development of elafin

    Protein-protein interaction network analysis of human fibroblast cells treated with ethanol

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    Introduction: Studies show that ethanol can induce changes in proteomic profile of human fibroblast cells. Some of these proteins are important in promoting cancer. Thus, analyzing function and interaction networks of these proteins are essential for better understanding the carcinogenesis mechanism of ethanol. Materials and Methods: In this study the protein-protein interaction network (PPI) of six significant down-regulated proteins in human fibroblast cells (HFFF2) treated with ethanol were analyzed by using Cytoscape software and its algorithms. Results: PPI network analysis showed that the constructed network consisted of 756 nodes and 1166 edges. Results indicated that Heterogeneous nuclear ribonucleoprotein A1 with degree = 528 and Betweenness Centrality = 0.74 is a hub protein that ethanol can alter its expression. In addition, module evaluation showed that the hub protein has a key role in different overlapped complexes. On the other hand, annotation studies by using DAVID program indicated that this protein is involved in different important biological processes in the cell. Conclusion: The six down-regulated proteins treated with ethanol may become carcinogenic and can impose vast alterations in other vital biological processes of the cell. Among them, Heterogeneous nuclear ribonucleoprotein A1 is the most important one. © 2016, Semnan University of Medical Sciences. All rights reserved
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