Isolation Virulence genes ETA, OPrL, gyrB in Pseudomonas aeruginosa clinical samples from hospitals in Kerman by Multiplex-PCR

زمینه و هدف: سودوموناس آئروژینوزا یک پاتوژن فرصت طلب و عامل عفونت های بیمارستانی و مرگ و میر به خصوص در بیماران با ضعف سیستم ایمنی می باشد و مقاومت ذاتی به مواد ضد میکروبی منجر به مشکلاتی در درمان عفونت های آن می شود. هدف از این مطالعه بررسی فراوانی ژن های حدت سودوموناس آئروژینوزا به روش Multiplex-PCR می باشد. روش بررسی: 60 نمونه سودوموناس آئروژینوزا شامل 40 نمونه از کلکسیون آزمایشگاه میکروبیولوژی پاسارگاد و 20 نمونه از بیمارستان های استان کرمان جمع آوری و در محیط های اختصاصی کشت داده و با آزمون های بیوشیمیایی تأیید شد. واکنش PCR بر روی تمامی نمونه ها برای شناسایی ژن های حدت gyrB, oprL, ETAو شناسایی جنس و گونه 16SrDNA صورت گرفت. یافته ها: از میان 60 نمونه سودوموناس آئروژینوزا، 38 نمونه (3/63) دارای ژن gyrB و oprL، 37 نمونه (6/61) دارای ژن ETA و هر 60 نمونه (100) دارای ژن 16SrDNA بودند. نتیجه گیری: با توجه به اهمیت تشخیص سریع این باکتری به جهت بروز مقاومت و مشکلات موجود در روش های بیوشیمیایی، شناسایی همزمان چندین ژن با روش Multiplex-PCR به­عنوان روشی حساس و دقیق در شناسایی این باکتری به شمار می رود

Hidden Conformal Symmetry of Kerr-Bolt Spacetimes

We extend the recent proposal of hidden conformal symmetry to the four-dimensional spacetimes with rotational parameter and NUT twist. We consider the wave equation of a massless scalar field in background of Kerr-Bolt spacetimes and show in the "near region", the wave equation can be reproduced by the $SL(2,R)_L \times SL(2,R)_R$ Casimir quadratic operators. Moreover, we compute the microscopic entropy of the dual CFT by Cardy formula and find a perfect match to Bekenstein-Hawking entropy of Kerr-Bolt spacetimes. The absorption cross section of a near region scalar field also matches to microscopic absorption cross section of the dual CFT.Comment: 9 pages, re-organized and re-writtend, typos corrected, main results and conclusion unchange

Real-time Measurement of Stress and Damage Evolution During Initial Lithiation of Crystalline Silicon

Crystalline to amorphous phase transformation during initial lithiation in (100) silicon-wafers is studied in an electrochemical cell with lithium metal as the counter and reference electrode. It is demonstrated that severe stress jumps across the phase boundary lead to fracture and damage, which is an essential consideration in designing silicon based anodes for lithium ion batteries. During initial lithiation, a moving phase boundary advances into the wafer starting from the surface facing the lithium electrode, transforming crystalline silicon into amorphous LixSi. The resulting biaxial compressive stress in the amorphous layer is measured in situ and it was observed to be ca. 0.5 GPa. HRTEM images reveal that the crystalline-amorphous phase boundary is very sharp, with a thickness of ~ 1 nm. Upon delithiation, the stress rapidly reverses, becomes tensile and the amorphous layer begins to deform plastically at around 0.5 GPa. With continued delithiation, the yield stress increases in magnitude, culminating in sudden fracture of the amorphous layer into micro-fragments and the cracks extend into the underlying crystalline silicon.Comment: 12 pages, 5 figure

Cytogenetic study on Artemia from Urmiyah Lake

To determine the chromosome numbers of artemia brine-shrimp in Urmiyah Lake (Azarbaijan-e- Gharhi province), cytogenetic studies were carried out on artemia cysts. In order to identify the collected samples, each sample of cysts, first incubated in sea water (35 ppt salinity) and then to determine the reproduction mode, the cyst samples were feed with Dunaliella tertiolecta, for three generations (F3) up to adult. The results showed that there were two types of anemia in terms of reproduction mode, namely bisexual and parthenogenesis. Chromosome spreads were prepared from freshly hatched nauplius squashing method. The results of counting 100 metaphases plates from bisexual artemia and 35 metaphases plates of parthenogenetic specimen, it was found that the number of chromosomes in these 2 types of artemia were the same, 2n=42. In these population, very small chromosomes with metacentric, submetacentric, telocentric and acrocentric types were observed. Karyotype formulas of bisexual and parthenogenetic artemia were determined as 2n=30 M / SM+12 A/T and 2n=32 M / SM+10 A/T, respectively. All studied samples in Interphase stage lacked and chromocenter. Due to very small size of chromosomes, it was difficult to do precise determination of the type of chromosomes and in this regard various C.banding experiments were performed. Also, since chromosomes in artemia lacked any chromocenter, the differentiation of chromosomes based on the types of C.banding was impossible

Modeling of wind energy conversion system using PSCAD/EMTDC

This paper aims to model a complete wind energy conversion system (WECS) connected to a grid. The motivation comes from the Distributed Generation System (DGS) installed at the Renewable Energy Lab at UMass Lowell. The objective of this work is to develop universal and standardized manufacturer independent textbook models. Manufacturer specific models are more accurate and detailed, but proprietary and non-disclosure agreements become an issue for research purposes. Since the wind turbines installed in the lab are VSWT (Variable Speed Wind Turbine) with Permanent Magnet Synchronous Generators (PMSG), so such a turbine system is modeled to represent them in general. PMSG requires very less maintenance and has high efficiency since it doesn't have rotor current and is used without a gearbox. Further, there are two more advantages: first, it has the capability of variable speed control due to the fact that its rotor speed can change in a large range; second, it's excitation system is independent of the grid and require any other excitation source. In addition to the turbine generator, other main components of WECS are also modeled namely: wind source model, wind turbine, permanent magnet synchronous generator and AC/DC/AC control. The equations governing these models are also discussed. The entire generation system is implemented on PSCAD/EMTDC and integrated to a grid and a basic fault analysis is done under different conditions. The proposed model can be used for research purposes on distributed generation issues. This model provides a good software simulation test bed for further research

Effect of different light regimes on the maturational progress of the whitespotted rabbitfish (Siganus sutor)

In this study, the effects of different light regimes on the reproductive activity of a typical Indo-Pacific coral reef rabbitfish, Siganus sutor, were evaluated. Forty-five adult fish were exposed to nine different photoperiod (8L: 16D, 12L: 12D, 16L: 8D) and light intensity (1000, 2000, 3000 lux) combinations with three replicates and five other fishes reared under indoor light condition (Control). Gonadosomatic Index (GSI) and Hepatosomatic Index (HSI) were calculated after 60 days and compared among different experimental regimes in males and females. In the control group, GSI and HSI mean values were 4.67 and 3.24%, respectively, for females and 10.05 and 2.10%, respectively, for males, and these fish showed differences in comparison with the exposed fish. Females kept under 1000 and 2000 lux light intensities had a higher GSI mean value (9.26 and 10.39%, respectively) and also lower average HSI (2.10 and 2.31%, respectively) in 16L: 8D treatment. A similar result was also obtained for males, whereas the 3000 lux light intensity, 8L: 16D day length combination led to more gonadal development (GSIs of 16.41% in females and 12.03% in males). A comparison of results among different photoperiods also confirmed that maturation was induced better in fish maintained under 16L: 8D in both sexes. This investigation revealed the visible role of both photoperiod and light intensity on inducing maturity in the whitespotted rabbitfish, S. sutor. Thus, rearing of adults exposed to an artificial light regime, including 16L: 8D and 2000 lux light intensity, promotes more gonadal development than that occurring in the wild

Effects of Daphnia magna and Artemia nauplii on growth performance in Persian sturgeon Acipenser persicus larvae

This study was carried out in a completely randomized design 3×3×4 factorial arrangement in three periods of rearing in spring 1997. Density of 300 larvae was assigned for each oval tank with 0.1m2 surface area, 30cm deep, a volume of 20lit and 0.25 lit/min of water flow per minute at Shahid Rajaie fish breeding and culture center in Sari, north of Iran. The fries were divided into three groups according to their feeding regimes and fed with each of Artemia or D. magna separately, and mixture of the two (50% Artemia+50% Daphnia) in ratioes of 80, 100 and 120% of their body weights in the first period and 30,50,70% of their body weights in the second and third period of rearing. Each period lasted 72 hours. The result indicated, significant differences (p<0.005) between food organisms, body weight gain and Food conservation Ratio (FCR) in the first and third period of rearing. The highest body weight gain was found in 120% food ratio in the first period. The best survival rate achieved with fries feeding at 70% body weight of Artemia nauplii and mixed food in the second period of rearing. The highest growth rate, survival rate and the best FCR obtained when Artemia fed as live food to fries. There were no significant differences between Artemia and mixed food in this study. It seems that mixed food (50% Artemia +50% Daphnia) given at 70% of larval body weight results in a better performance

Evaluation of different dietary protein and energy levels on growth performance and body composition of narrow clawed crayfish (Astacus leptodactylus)

Nine practical diets containing increasing percentages of crude protein (CP) and energy (30%, 35%, 40% and 300kcal/100g, 370kcal/100g and 450kcal/100g) were fed to narrow clawed crayfish (mean individual weight=17±2.3 g) during an 8 week feeding trial. Weight Gain, Feed conversion ratio (FCR), Protein Efficiency Ratio (PER), Net Protein Utilization (NPU), Daily Food Consumption (DFC) and body composition of tail-muscle meat of narrow clawed crayfish were determined. At the conclusion of the experiment, comparing the growth parameters in response to interaction between protein and energy levels demonstrated that dietary number 2 (30/370) resulted in higher WG, NPU, PER, and the lowest FCR whereas dietary number 3 (30:450) showed higher SGR and DFC. Comparison of the body composition results indicates the greatest amount of protein absorption in diet number 2 (30/370). Results from this study indicate that narrow clawed crayfish can be fed a practical diet containing 30% protein and 370 Kcal/100gr. Reducing CP levels in narrow clawed crayfish diets may help reduce operating costs and thereby increase producers’ profits

Determination spawning season and changes in reproduction cycle of Schizothorax zarudnyi and condition factor in Hamoon Lake

Schizothorax zarndnyi is one of the most economic and endemic species, which are found in rivers and triple lagoons of Hamoon. In this study, reproduction cycle, type, season and optimum temperature of spawning period was studied from July 1998 to June 1999. The maximum GSI was 7.9-9.6 in March and April with 14-18°C mean temperatures. The minimum GSI was 0.92 in May. Variation in GSI values shows that reproduction has annual cycle which begins in May and ends in April of the next year. From October significant increase of oocyte diameter and GSI were observed in 2 different groups, while oocyte distribution observed only in one group in May. The rate of HSI had flucatuation, during resting period of ovule (from May to September) and from October simultaneously with significant increase of GSI, the HSI increased and continued to January and decreased in March and April. The condition factor, was changed during reproduction cycle and it was minimum in March (0.92). Concerning these investigation, Sch. zarndnyi is a total spawner and showing a synchronous ovary