1,270 research outputs found

    Thermophysical Properties of Bi-based High-Tc Superconductors

    Get PDF

    Synthesis and characterization of thermally stable poly(amide-imide)-montmorillonite nanocomposites based on bis(4-carboxyphenyl)-N,N'-pyromellitimide acid

    Get PDF
    Two new poly(amide-imide)-montmorillonite reinforced nanocomposites containing bis(4-carboxyphenyl)-N,N'-pyromellitimide acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) as a source of polymer matrix was synthesized by the direct polycondensation reaction of  bis(4-carboxyphenyl)-N,N'-pyromellitimide acid  with 4,4'-diamino diphenyl sulfone in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films with 10 and 20% silicate particles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-Vis spectroscopy, thermal gravimetry analysis (TGA) and water uptake measurements. KEYWORDS: Bis(4-carboxyphenyl)-N,N'-pyromellitimide acid moiety, Poly(amide-imide)-montmorillonite nanocomposite, Thermal properties Bull. Chem. Soc. Ethiop. 2013, 27(1), 95-104.DOI: http://dx.doi.org/10.4314/bcse.v27i1.1

    The effect of changing position and early ambulation after cardiac catheterization on patients' outcomes: A single-blind randomized controlled trial

    Get PDF
    Background: Cardiac catheterization is the gold standard diagnostic test for coronary heart diseases. In order to minimize the post-procedure complications, patients are restricted to prolonged bed rest that is always accompanied by fatigue and discomfort. Objective: The aim of this study was to assess the effect of changing position and early ambulation on the level of comfort, satisfaction, and fatigue and on the amount of bleeding and hematoma after cardiac catheterization. Participants: A sample of 70 patients, who had undergone a non-emergency 6-French cardiac catheterization via the femoral artery from September to November, 2006. Methods: In a single-blind randomized controlled trial, each patient was randomly assigned to either the control or experimental group. The patients' position in the experimental group was intermittently changed during the first 6 h after catheterization. Seven hours after the procedure, they were allowed to be ambulated and to undertake their self care activities. A pillow was placed under the patients' bodies. Patients in the control group were managed as routine; they were restricted to a 10-24 h bed rest bed rest in supine position with the affected leg straight and immobilized and a sand bag on the puncture site for at least 8 h. The levels of comfort, satisfaction and fatigue, and the amount of bleeding and hematoma were measured at regular intervals after the procedure. Results: The patients in the experimental group had significantly higher comfort and satisfaction and lower fatigue levels than the control group at 3, 6, 8 h and the next morning after catheterization (P 0.05). Conclusion: The results of this study showed that the levels of comfort, satisfaction and fatigue after catheterization are related to the duration of bed rest and patients' position in bed. Changing patients' position accompanied by early ambulation after cardiac catheterization are associated with increasing comfort and satisfaction levels and decreasing the level of fatigue without increasing the amount of bleeding and hematoma. © 2009 Elsevier Ltd. All rights reserved

    Identification of SSR and RAPD markers associated with QTLs of winter survival and related traits in Brassica napus L.

    Get PDF
    Because of importance of winter survival in winter type of Brassica napus, this study was performed to identify the QTLs controlling winter survival and related traits using SSR and RAPD markers. For this,an F2:3 population of 200 families derived from crossing between cv. ‘SLMO46’ (winter type and cold resistant) and cv. ‘Quantum’ (spring type and susceptible to low temperature) were used. Wintersurvival (WS), leaves per plant in rosette stage (L/P), crown wet weight (CWW), crown dry weight (CDW) and crown water content (CWC) were measured in F3 families. 350 SSR primer pairs and 250 RAPDprimers were used to assess the parental polymorphism. The 32 SSR primer pairs and 47 RAPD polymorphic markers between parental lines were used to screen F2 individuals. Linkage map was constructed using polymorphic markers. The markers were assigned into 14 linkage groups with total length of 1199.1 cM and an average distance of 17.13 cM between adjacent markers. The relationship between measured traits and genotypic data was analyzed using CIM method and totally 12 putative QTLs were detected for studied traits. The explained phenotypic variance by identified QTLs ranged between 0.5 and 11%. The identified QTLs had positive and negative additive effects and transferred from both parents to F2 plants and F3 families. Some of these QTLs located in the same genomic regions

    Seasonal Variation in Exposure Level of Types A and B Ultraviolet Radiation: An Environmental Skin Carcinogen

    Get PDF
    Background: The main source of ultraviolet radiation (UVR) is the sun, affecting organs such as the skin, eyes, and immune system. According to American Conference of Governmental Industrial Hygienist (ACGIH) reports, the amount of UVR reaching the Earth’s surface is increasing yearly and is responsible for an increase in solar radiation‑related diseases. Aims: To investigate the amount of UVR reaching the Earth’s surface and understand the risk of UVR on disease among outdoor laborers in one of the central provinces of Iran.Materials and Methods: Arak city was divided into two geographic areas, and the weekly measurement of UVR was done in three locations) asphalt, grass and rooftop). To measure UVR, Hanger UV spectrometer, standard deviation (SD8‑A), and SD8‑B detectors were used. Amounts of UVR for a consecutive year and varying weather conditions were measured. Finally, values obtained were compared to ACGIH standards. Results: The minimum and maximum levels of UV type A radiation occurred in April 1.27 (0.724) W/m2 and September 7.147 (4.128) W/m2, these figures for UV type B were in March–April 0.005 (0.003) and September 0.083 (0.077). The maximum UVR is received between 11 and 15 o’clock.Conclusions: In the central cities of Iran, the minimum and maximum UV type A and B is received in March–April and in September, respectively. Based on the results, the angular position of the sun in the sky, cloud cover, and height from ground level affected the amount of UVR received, but the geographic locations studied did not.  Keywords: Outdoor Job, Skin Cancer, Carcinogen, Ultraviolet radiation, Ultraviolet A, Ultraviolet B, Ira

    Karyological study of the medicinal plant Papaver rhoeas from northwest of Iran

    Get PDF
    Karyotype and morphology of mitotic chromosomes in six populations of the medicinal plant Papaver rhoeas collected from various geographical locations of the northwest of Iran were studied. Chromosome characteristics were measured from 10 complete metaphase cells using micromeasure software. The results showed that P. rhoeas is a diploid species with 2n=2x=14 chromosomes. The karyotype consisted of seven pairs of submetacentric chromosomes with one pairs of SAT chromosome (chromosome 2) having a secondary constriction at the end of its short arm. Karyological characteristics of all the materials studied were similar to each other; however, there were some variations on chromosome arm ratios and relative lengths among the different populations. All of the populations are placed on 4A class of Stebbin’s asymmetry categories.Key words: Biodiversity, chromosome analysis, medicinal plants, Papaveraceae

    Evaluating the effect of a herb on the control of blood glucose and insulin-resistance in patients with advanced type 2 diabetes (a double-blind clinical trial)

    Get PDF
    Background: Different benefits of various herbal medicines in decreasing blood sugar have been reported in different clinical trials so far. Considering the growing tendency toward these combinations and the booming market, inappropriate advice is growing accordingly. Hence, it is necessary to evaluate the effects and possible complications of such combinations on health status and blood glucose control. Methods: Two 38-subject groups were formed and a 12-week treatment program was administered for both groups. The inclusion criteria were failure to control blood glucose with two oral medicines, unwillingness to inject insulin. The medicine was prepared in capsules by Booali Company. Each capsule weighed 750 mg and contained nettle leaf 20 (w/w), berry leaf 10 (w/w), onion and garlic 20 (w/w), fenugreek seed 20 (w/w), walnut leaf 20 (w/w), and cinnamon bark 10 (w/w) all in powder. Results: At the beginning of the study, there was no significant difference between the subjects regarding the evaluated parameters, but after the intervention, the level of glucose was significantly lower in fasting (P=0.0001) and 2-hour postprandial (P=0.002) levels. The level of glycated hemoglobin A1c (HbA1c) (P=0.0001) also decreased from 0.33±9.72 to 0.20±8.39 . Finally, the level of insulin resistance reduced from 1.9±4.1 to 1.4±2.6 (P=0.001) after consuming herbal medicine. Conclusion: According to the results of the current study, the herbal combination was effective in controlling blood sugar, and considering the reduction of HbA1c by 1.31 , it seems that the herbal combination is an effective medicine to treat diabetes. © 2020 Babol University of Medical Sciences. All rights reserved
    • …
    corecore