排序方式: 共有41条查询结果,搜索用时 15 毫秒
21.
Sadegh Fattahi Mohammad Karimi Alivije Farhang Babamahmoodi Masomeh Bayani Mahmoud Sadeghi Haddad Zavareh Mohsen Asouri Maryam Lotfi Galia Amirbozorgi Haleh Akhavan-Niaki 《Indian journal of clinical biochemistry : IJCB》2018,33(4):467-472
Hepatitis B virus (HBV) infection is a worldwide health concern which is associated with significant morbidity and mortality. Both viral and host factors have a significant effect on infection, replication and pathogenesis of HBV. The aim of this study was to investigate the effect of CYP2E1 and CYP1A1 genetic variants on susceptibility to HBV. 143 individuals including 54 chronic HBV patients and 89 healthy controls were enrolled in the genotyping procedure. rs2031920 and rs3813867 at CYP2E1 as well as rs4646421 and rs2198843 at CYP1A1 loci were studied in all subjects using PCR–RFLP (restriction fragment length polymorphism) analysis. Both variants at CYP2E1 locus were monomorphic in all studied subjects. Genotype frequency of rs4646421 was significantly different between chronic HBV patients and healthy blood donors (P = 0.04, OR 4.31; 95% CI 1.04–17.7). Furthermore, individuals carrying at least one C allele (CC or CT genotypes) for rs4646421 seemed to have a decrease risk of hepatitis in comparison with TT genotype (P = 0.039). Our results showed a relationship between rs4646421 TT genotype (rare genotype) and the risk for developing chronic HBV infection (four times higher). Further studies are needed to examine the role of CYP1A1 polymorphism in susceptibility to chronic HBV infection. 相似文献
22.
In this paper, we propose a technique for lowering the latency of the communication in a NoC (network on chip). The technique, which can support two qualities of service (QoS), i.e., the guaranteed throughput (GT) and best effort (BE), is based on splitting a wider link into narrower links to increase throughput and decrease latency in the NoC. In addition, to ease the synchronization and reduce the crosstalk, we use the l-of-4 encoding for the smaller buses. The use of the encoding in the proposed NoC architecture considerably lowers the latency for both BE and GT packets. In addition, the bandwidth is increased while the power consumption of the links is reduced. 相似文献
23.
The interaction of two identical polar neutral molecules is modeled by two equal but oppositely charged point particles at a fixed distance of separation. The total Coulomb potential energy of this system is calculated as a function of this distance, x, and the distance, y, between their centers of mass. We find that when the y/x ratio is less than about 3.1619, the linear configuration has the lower energy, whereas when this ratio exceeds 3.1619, a stacked structure is more stable. Interestingly, when two real polar molecules, such as HF interact, neither of these structures are formed. It is ‘hydrogen bonded’. The NaF dimer on the other hand, has a global minimum as stacked structure at a y/x ratio of about 1, significantly smaller than 3.1619! 相似文献
24.
提出一种在车辆自组织网络(VANET)中应用的无线多跳视频传输实验系统的设计和实现方案及其对应的传输控制和路由选择协议.该系统将嵌入式Linux与IEEE 802.11n传输协议集成到ARM内核,由S3C6410主控模块、无线局域网网卡及LCD屏等构成.针对VANET的无线多跳视频传输场景,对视频编译码分别采用H.264和JPEG两种标准实现并对它们的压缩比、时延、传输丢包率等性能进行了理论分析和实验比较,进行了室内室外多种不同场景的实际测试.结果表明:所设计的多跳视频传输实验系统方案能够适应VANET等多种场景的应用,所提出的传输控制和路由选择协议能够保证视频传输的多跳和实时性要求. 相似文献
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26.
Van-Quang-Binh Ngo Mohsen Latifi Rabeh Abbassi Houssem Jerbi Kentaro Ohshima Mehrdad khaksar 《Journal of The Franklin Institute》2021,358(7):3491-3511
In recent years, Photovoltaic (PV) systems have been received great attention all over the words as they are sustainable, unlimited and environmentally friendly energy. However, it is required for the PV system to apply a tracking controller to guarantee efficient operation by extracting the maximum power, which named maximum power point tracking (MPPT) method. Due to the simple structure, the conventional perturb and observe (P&O) MPPT algorithm is very popular in the literature. Nevertheless, conventional methods show inaccurate performance, particularly when high variations occur in irradiance, resulting in fluctuations around the MPP. To deal with these challenges, a novel technique on the basis of the variable-step size of P&O MPPT and sliding mode controller (SMC) adjusted by the θ-modified krill herd (θ-MKH) algorithm is presented. The θ-MKH algorithm is utilized to fine-tune the optimal SMC parameters to drive the variable step of the classical P&O algorithm. Simulations are prepared to compare the performance of the suggested scheme with conventional methods by considering simultaneous fast changes of irradiance and temperature. The results show that the suggested scheme have proper performance in both transient and steady-state, particularly under quickly varying climate circumstances. 相似文献
27.
Alireza Nakhaee Mohammad Bokaeian Mohsen Saravani Ali Farhangi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2009,24(4):419-425
In traditional medicine, Eucalyptus globulus (eucalyptus) was used for the treatment of diabetes mellitus. Hyperglycemia in
diabetes has been associated with increased formation of reactive oxygen species (ROS) and oxidative damage to tissue compounds.
The aim of this study was to evaluate the effects of eucalyptus in the diet (20 g/Kg) and drinking water (2.5 g/L) on lipid
peroxidation, protein oxidation and antioxidant power in plasma and liver homogenate, as well as glycated-Hb (HbA1C) of blood in streptozotocin-induced diabetic rats for a period of 4 weeks. Diabetes induced in rats by a single intraperitoneal
injection of streptozotocin (STZ, 65 mg/Kg). At the end of the treatment period, the level of plasma glucose, plasma and liver
malondialdehyde (MDA, the main product of lipid peroxidation), protein carbonyl (PC, one of the protein oxidation products)
and HbA1C increased and ferric reducing antioxidant power (FRAP) decreased in diabetic rats compared to normal rats. Eucalyptus administration
for 4 weeks caused a significant decrease in the plasma glucose levels, plasma and liver MDA, PC and HbA1C, also a concomitant increase in the levels of FRAP in diabetic treated rats. In conclusion, the present study showed that
eucalyptus posses antioxidant activities. Eucalyptus probably restores antioxidant power, due to the improved hyperglycemia
in streptozotocin-induced diabetic rats. 相似文献
28.
Some two-microphone noise reduction techniques that work in the frequency domain exploit coherence function between two noisy signals. They have shown good results when noise signals on two sensors are uncorrelated, but their performance decreases with correlated noises. Coherence based methods can be improved when the cross power spectral density (CPSD) of correlated noise signals is available. In this paper, we propose a new method for estimation of the CPSD of the noise, which is based on the minimum tracking technique. Despite the fact that the proposed estimator does not need to implement a voice activity detector (VAD), its performance is comparable to a CPSD estimator that uses an ideal VAD. 相似文献
29.
This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) are the utilized FACTS devices. Our objectives are active power loss reduction, newly introduced FACTS devices cost reduction, voltage deviation reduction, and increase on the robustness of the security margin against voltage collapse. The operational and controlling constraints, as well as load constraints, were considered in the optimum allocation. A goal attainment method based on the genetic algorithm (GA) was used to approach the global optimum. The estimated annual load profile was utilized in a sequential quadratic programming (SQP) optimization sub-problem to the optimum siting and sizing of FACTS devices. Fars Regional Electric Network was selected as a practical system to validate the performance and effectiveness of the proposed method. The entire investment of the FACTS devices was paid offand an additional 2.4% savings was made. The cost reduction of peak point power generation implies that power plant expansion can be postponed. 相似文献
30.
Mir Mohammad Sadeghi Mohsen Azad Manjir Fatemeh Fahimifar Mohammad Javad 《Learning Environments Research》2020,23(1):117-128
Learning Environments Research - The purpose of present study was to examine the effect of friendship and relationship dimensions of the classroom environment on general and academic selfconcept.... 相似文献