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Dehghani MH Mahvi AH Jahed GR Sheikhi R 《Journal of Zhejiang University. Science. B》2007,8(7):493-497
The objective of the investigation was to study the application of ultrasound reactor technology (USRT) as a disinfectant for reduction of fungi from sewage effluent. Fungi are carbon heterotrophs that require preformed organic compounds as carbon sources. USRT is an attractive means to improve water quality because of the system simplicity and no production of toxic by-products. An ultrasound reactor produces strong cavitation in aqueous solution causing shock waves and reactive free radicals by the violent collapse of the cavitation bubble. These effects should contribute to the physical disruption of microbial structures and inactivation of organisms. There was significant reduction in fungal growth, with decreased fungal growth with increasing USRT. In this study, ultrasound irradiation at a frequency of 42 kHz was used to expose suspensions of fungi to evaluate the disinfection efficacy of the ultrasound reactor. Also, this study showed that in this system more than 99% reduction of sewage fungi was achieved after 60 min. 相似文献
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Hossein Motamedi Esmaeil Darabpour Mahnaz Gholipour Seyyed Mansour Seyyed Nejad 《Journal of Zhejiang University. Science. B》2010,11(7):506-511
Brucellosis, a zoonosis caused by four species of brucella, has a high morbidity. Brucella melitensis is the main causative agent of brucellosis in both human and small ruminants. As an alternative to conventional antibiotics,
medicinal plants are valuable resources for new agents against antibiotic-resistant strains. The aim of this study was to
investigate the usage of native plants for brucellosis treatment. For this purpose, the anti-brucella activities of ethanolic
and methanolic extracts of Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, Plantago ovata, Cordia myxa, and Crocus sativus were assessed. The activity against a resistant Br. melitensis strain was determined by disc diffusion method at various concentrations from 50–400 mg/ml. Antibiotic discs were also used
as a control. Among the evaluated herbs, six plant (Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, and Crocus sativus) showed anti-brucella activity. Oliveria decumbens was chosen as the most effective plant for further studies. A tested isolate exhibited resistance to tetracycline, nafcillin,
oxacillin, methicillin, and colistin. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)
values for Oliveria decumbens against resistant Br. melitensis were the same (5 mg/ml), and for gentamicin they were both 2 mg/ml. Time-kill kinetics for a methanolic extract of Oliveria decumbens was 7 h whereas for an ethanolic extract it was 28 h. Also, Oliveria decumbens extracts showed a synergistic effect in combination with doxycycline and tetracycline. In general, the similar values of
MIC and MBC for Oliveria decumbens suggest that these extracts could act as bactericidal agents against Br. melitensis. In addition to Oliveria decumbens, Crocus sativus and Salvia sclarea also had good anti-brucella activity and these should be considered for further study. 相似文献
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E-Government and E-Government development project studies have been conducted in most industrialized societies, as well as in Iran. Due to their nature and structure, E-Government development projects have numerous political, social, and economic impacts on society. Given the incorporation of significant capital, human resources, information, and political commitments, these projects are considered quite vital to society. Following the systematic pre-implementation activities of E-Government development projects is critical for the success of such projects; ignoring such issues leads to various problems during E-Government project implementation. This research aims to explore and detect the success indicators for pre-implementation activities of E-Government development projects, evaluate the validity of these indicators, and investigate the indicators' status in the Fuel Smart Card Project. The researcher has also provided some suggestions on the successful implementation of E-Government development projects. 相似文献
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Abdorrahim Absalan Javad Mohiti-Ardakani Hossein Hadinedoushan Mohammad Ali Khalili 《Indian journal of clinical biochemistry : IJCB》2012,27(4):351-356
Cinnamon has been used as an anti-diabetic agent for centuries but only in recent few years its mechanism of action has been under investigation. Previous studies showed that cinnamon might exert its anti-diabetic effect via increasing glucose transporter isotype-4 (GLUT4) gene and glycoprotein contents in fat cells. To study if hydro-alcoholic cinnamon extract (HACE) enhances GLUT4 translocation from intracellular compartments of nuclear or endoplasmic reticulum membranes (N/ER) into the cytoplasmic membrane (CM). C2C12 myoblastic cell line were seeded in DMEM plus 20 % FBS and differentiated to myotubes using 2 % horse serum. After myotubes formation, 100 or 1,000 μg/ml HACE, as intervention, and as control 1 % DMSO were added for 3 h. Cells were washed and homogenized followed by ultracentrifuge fractionation, protein separation by SDS-PAGE and GLUT4 detection using semi-quantitative Western blotting. Data analysis was done by two-independent samples t test for comparison of mean ± SD of GLUT4 percent in categories. GLUT4 contents were higher in CM of groups 100 and 1,000 μg/ml HACE and lower in 1 % DMSO treated myotubes (CI = 0.95, P < 0.05). For N/ER reverse results were obtained (CI = 0.95, P < 0.05). As our results have shown HACE induces GLUT4 translocation from intra-cell into cell surface. We conclude that cinnamon maybe a choice of type-2 diabetes mellitus treatment because its extract enhances GLUT4 contents in CM where it facilitates glucose entrance into the cell. However it is necessary to trace the signaling pathways which are activated by HACE in muscular tissue. 相似文献
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Whether screening tests or teacher ratings best predict children at risk for reading failure continues to be an area of disagreement in the early identification literature. Our early studies confirmed low positive identification rates (30%) when kindergarten teachers were asked to predict future reading achievement using a traditional rating scale, while a project-developed, theory-based screening battery correctly identified 81% of poor readers. Construction of a teacher rating scale of current skill levels on research-validated precursors to reading improved prediction in the current study, although results were still inferior to the screening test (64% and 80% valid positives, respectively). Combining test results and teacher ratings resulted in 88% identification of those who failed in first, second, or third grade, suggesting that both teacher ratings and screening tests should be used to identify the largest number of those who will later fail in reading. © 1998 John Wiley & Sons, Inc. 相似文献
28.
Amir D. Aczel 《Science & Education》2004,13(7-8):675-687
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Implantable drug delivery devices are becoming attractive due to their abilities of targeted and controlled dose release. Currently, two important issues are functional lifetime and non-controlled drug diffusion. In this work, we present a drug delivery device combining an electrolytic pump and a thermo-responsive valve, which are both remotely controlled by an electromagnetic field (40.5 mT and 450 kHz). Our proposed device exhibits a novel operation mechanism for long-term therapeutic treatments using a solid drug in reservoir approach. Our device also prevents undesired drug liquid diffusions. When the electromagnetic field is on, the electrolysis-induced bubble drives the drug liquid towards the Poly (N-Isopropylacrylamide) (PNIPAM) valve that consists of PNIPAM and iron micro-particles. The heat generated by the iron micro-particles causes the PNIPAM to shrink, resulting in an open valve. When the electromagnetic field is turned off, the PNIPAM starts to swell. In the meantime, the bubbles are catalytically recombined into water, reducing the pressure inside the pumping chamber, which leads to the refilling of the fresh liquid from outside the device. A catalytic reformer is included, allowing more liquid refilling during the limited valve''s closing time. The amount of body liquid that refills the drug reservoir can further dissolve the solid drug, forming a reproducible drug solution for the next dose. By repeatedly turning on and off the electromagnetic field, the drug dose can be cyclically released, and the exit port of the device is effectively controlled. 相似文献