57 research outputs found

    Hard-wall Potential Function for Transport Properties of Alkali Metals Vapor

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    This study demonstrates that the transport properties of alkali metals are determined principally by the repulsive wall of the pair interaction potential function. The (hard-wall) Lennard-Jones(15-6) effective pair potential function is used to calculate transport collision integrals. Accordingly, reduced collision integrals of K, Rb, and Cs metal vapors are obtained from Chapman-Enskog solution of the Boltzman equation. The law of corresponding states based on the experimental-transport reduced collision integral is used to verify the validity of a LJ(15-6) hybrid potential in describing the transport properties. LJ(8.5-4) potential function and a simple thermodynamic argument with the input PVT data of liquid metals provide the required molecular potential parameters. Values of the predicted viscosity of monatomic alkali metals vapor are in agreement with typical experimental data with the average absolute deviation 2.97% for K in the range 700-1500 K, 1.69% for Rb, and 1.75% for Cs in the range 700-2000 K. In the same way, the values of predicted thermal conductivity are in agreement with experiment within 2.78%, 3.25%, and 3.63% for K, Rb, and Cs, respectively. The LJ(15-6) hybrid potential with a hard-wall repulsion character conclusively predicts best transport properties of the three alkali metals vapor.Comment: 21 pages, 5 figures, 41 reference

    Use of an orthovoltage X-ray treatment unit as a radiation research system in a small-animal cancer model

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    <p>Abstract</p> <p>Background</p> <p>We explore the use of a clinical orthovoltage X-ray treatment unit as a small-animal radiation therapy system in a tumoral model of cervical cancer.</p> <p>Methods</p> <p>Nude mice were subcutaneously inoculated with 5 × 10<sup>6 </sup>HeLa cells in both lower limbs. When tumor volume approximated 200 mm<sup>3 </sup>treatment was initiated. Animals received four 2 mg/kg intraperitoneal cycles (1/week) of cisplatin and/or 6.25 mg/kg of gemcitabine, concomitant with radiotherapy. Tumors were exposed to 2.5 Gy/day nominal surface doses (20 days) of 150 kV X-rays. Lead collimators with circular apertures (0.5 to 1.5 cm diameter) were manufactured and mounted on the applicator cone to restrict the X-ray beam onto tumors. X-ray penetration and conformality were evaluated by measuring dose at the surface and behind the tumor lobe by using HS GafChromic film. Relative changes in tumor volume (RTV) and a clonogenic assay were used to evaluate the therapeutic response of the tumor, and relative weight loss was used to assess toxicity of the treatments.</p> <p>Results</p> <p>No measurable dose was delivered outside of the collimator apertures. The analysis suggests that dose inhomogeneities in the tumor reach up to ± 11.5% around the mean tumor dose value, which was estimated as 2.2 Gy/day. Evaluation of the RTV showed a significant reduction of the tumor volume as consequence of the chemoradiotherapy treatment; results also show that toxicity was well tolerated by the animals.</p> <p>Conclusion</p> <p>Results and procedures described in the present work have shown the usefulness and convenience of the orthovoltage X-ray system for animal model radiotherapy protocols.</p

    Serum homocysteine level in gestational diabetes: a prospective study

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    &quot;n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Increased total plasma homocysteine (Hcy) is an accepted risk factor of cardiovascular disease (CVD), stroke, preclampsia, recurrent abortion and diabetes type I and II. The aim of the current study was to assess serum homocysteine and its relation with serum folat, vitamine B12 and lipid profile in gestational diabetes mellitus and to compare these with those of pregnant women.&quot;n&quot;n Methods: In a prospective controlled survey 80 pregnant women (24-28 weeks) with uncomplicated pregnancies were evaluated. They were assigned to one of two groups according to the results of 100g-OGTT. In the case group there were pregnant women with gestational diabetes mellitus according to the OGTT and in the control group women who had normal OGTT results were put. Levels of fasting glucose, homocysteine, vit B12, and folic acid, uric acid, total cholesterol, triglyceride, Low Density Lipoprotein cholesterol (LDL) and High Density Lipoprotein cholesterol (HDL) were measured in both groups.&quot;n&quot;nResults: The mean level of homocysteine in GDM group was significantly higher than control group (p=0.000). The mean level of folic acid and vit B12 was significantly lower than the level in control group (p=0.001, p=0.004 respectively). Body mass index (BMI) in GDM group was higher (p=0.000) and HDL level was lower (p=0.006) than control group. There were no significant differences among the groups with respect to levels of total cholesterol and triglyceride.&quot;n&quot;n Conclusion: We found that patients with gestational diabetes have higher homocysteine level than normal pregnant women. This increased level seems to be related to an abnormal OGTT. Further investigations are needed to follow up these patients in the postpartum period and later on

    Comparison of Saffron versus Fluoxetine in Treatment of Mild to Moderate Postpartum Depression: A Double-Blind, Randomized Clinical Trial

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    Introduction: Postpartum depression is a common mental health problem that is associated with maternal suffering. The aim of this double-blind clinical trial was to compare safety and efficacy of saffron and fluoxetine in treatment of mild to moderate postpartum depression. Methods: This was a 6-week, double-blind, randomized clinical trial. Subjects were women aged 18�45 years with mild to moderate postpartum depression who had Hamilton Depression Rating Scale (HDRS 17-item) score�18. Eligible participants were randomized to receive either a capsule of saffron (15 mg capsule) or fluoxetine (20 mg capsule) twice daily for 6 weeks. The primary outcome measure was to evaluate efficacy of saffron compared to fluoxetine in improving depressive symptoms (HDRS score). Results: There was no significant effect for time�treatment interaction on HDRS score F (4.90, 292.50)=1.04, p=0.37 between the 2 groups. 13 (40.60%) patients in the saffron group experienced complete response (�50% reduction in HDRS score) compared with 16 (50%) in the fluoxetine group and the difference between the 2 groups was not significant in this regard (p=0.61). Frequency of adverse events was not significantly different between the treatment groups. Discussion: The results of this study may suggest that saffron is a safe alternative medication for improving depressive symptoms of postpartum depression. Nevertheless, it should be mentioned that the trial is not well powered and should be considered a preliminary study. Therefore, large clinical trials with longer treatment periods and comparison with placebo group would be appropriate for future studies. Copyright © 2016, Georg Thieme Verlag KG. All rights reserved

    Isolation of high yield and quality RNA from human precision-cut lung slices for RNA-sequencing and computational integration with larger patient cohorts

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    Precision-cut lung slices (PCLS) have gained increasing interest as a model to study lung biology/disease and screening novel therapeutics. In particular, PCLS derived from human tissue can better recapitulate some aspects of lung biology/disease as compared to animal models. Several experimental readouts have been established for use with PCLS, but obtaining high yield and quality RNA for downstream analysis has remained challenging. This is particularly problematic for utilizing the power of next-generation sequencing techniques, such as RNA-sequencing (RNA-seq), for non-biased and high through-put analysis of PCLS human cohorts. In the current study, we present a novel approach for isolating high quality RNA from a small amount of tissue, including diseased human tissue, such as idiopathic pulmonary fibrosis (IPF). We show that the RNA isolated using this method has sufficient quality for RT-qPCR and RNA-seq analysis. Furthermore, the RNA-seq data from human PCLS could be used in several established computational pipelines, including deconvolution of bulk RNA-seq data using publicly available single-cell RNA-seq data. Deconvolution using Bisque revealed a diversity of cell populations in human PCLS, including several immune cell populations, which correlated with cell populations known to be present and aberrant in human disease

    Electrophysiological characteristics and outcome in patients with idiopathic right ventricular arrhythmia compared with arrhythmogenic right ventricular dysplasia

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    Background: Idiopathic right ventricular arrhythmias (IRVA) are responsive to medical and ablative treatment and have a benign prognosis. Arrhythmias caused by right ventricular dysplasia (ARVD) are refractory to treatment and may cause sudden death. It is difficult to distinguish between these two types of arrhythmia. Objective: To differentiate patients with IRVA and ARVD by a conventional electrophysiological study. Methods: 56 patients with a right ventricular arrhythmia were studied. They had no history or signs of any cardiac disease other than right ventricular dysplasia. They were classified as having IRVA (n = 41) or ARVD (n = 15) on the basis of family history, ECG characteristics, and various imaging techniques. They were further investigated by standard diagnostic electrophysiology. Results: The two groups were clearly distinguished by the electrophysiological study in the following ways: inducibility of ventricular tachycardia by programmed electrical stimulation with ventricular extrastimuli (IRVA 3% v ARVD 93%, p < 0.0001); presence of more than one ECG morphology during tachycardia (IRVA 0% v ARVD 73%, p < 0.0001); and fragmented diastolic potentials during ventricular arrhythmia (IRVA 0% v ARVD 93%, p < 0.0001). Data from the clinical follow up in these patients supported the diagnosis derived from the electrophysiological study. Conclusions: Patients with IRVA or ARVD can be distinguished by specific electrophysiological criteria. A diagnosis of ARVD can be made reliably on the basis of clinical presentation, imaging techniques, and an electrophysiological study
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