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61.
OBJECTIVES: To determine age-specific prevalence of hypertension and blood pressure (BP) levels in relation to diet and lifestyle factors in North Indians. DESIGN AND SETTING: Cross-sectional survey in 20 randomly selected streets in Moradabad, North India. SUBJECTS AND METHODS: A total of 1806 subjects from North India (904 males and 902 females) age range 25-64 years. The survey methods were as follows: dietary diaries for 7 days food intake record; BP measurements; physician administered questionnaire and anthropometric measurements. Diagnosis of hypertension was based on new World Health Organization/International Society of Hypertension (WHO/ISH) criteria. Risk factors were assessed based on WHO guidelines. RESULTS: The prevalence of hypertension according to WHO/ISH criteria was 23.7% and by old WHO criteria 13.3%. In the WHO/ISH hypertensive group, isolated diastolic hypertension was present in 47.3% males and 40.6% females. Males have a slightly higher prevalence than females in the young age group, however, the prevalence rates are comparable in the older age groups. In both sexes, the prevalence rates and BP level increased with older age. Multivariate analysis revealed that age, higher body mass index, central obesity and higher socioeconomic status were independently and strongly associated with hypertension in both sexes. Higher dietary fat and salt intake and lower physical activity were weakly but significantly associated with hypertension. CONCLUSION: Association of higher socioeconmic status, higher body mass index and central obesity in North Indian adults with higher fat intake, lower physical activity and higher prevalence and level of hypertension indicate that these populations may benefit by decreasing the dietary fat intake and increasing physical activity, with an aim to decrease central obesity for decreasing hypertension in North Indians.  相似文献   
62.
The 3D Underwater Sensor Network (USNs) has become the most optimistic medium for tracking and monitoring underwater environment. Energy and collision are two most critical factors in USNs for both sparse and dense regions. Due to harsh ocean environment, it is a challenge to design a reliable energy efficient with collision free protocol. Diversity in link qualities may cause collision and frequent communication lead to energy loss; that effects the network performance. To overcome these challenges a novel protocol Forwarder Selection Energy Efficient Routing (FSE2R) is proposed. Our proposal’s key idea is based on computation of node distance from the sink, Residual Energy (RE) of each node and Signal to Interference Noise Ratio (SINR). The node distance from sink and RE is computed for reliable forwarder node selection and SINR is used for analysis of collision. The novel proposal compares with existing protocols like H2AB, DEEP, and E2LR to achieve Quality of Service (QoS) in terms of throughput, packet delivery ratio and energy consumption. The comparative analysis shows that FSE2R gives on an average 30% less energy consumption, 24.62% better PDR and 48.31% less end-to-end delay compared to other protocols.  相似文献   
63.
Pulse compression is an important and burning issue in radar signal processing. In the recent past, many adaptive and neural network based methods have been proposed to achieve effective pulse compression performance for real coded transmitted waveforms. Even though the radar signal is complex, it is mostly processed as real-valued in-phase and quadrature components. Hence it is desirable that for processing complex radar signal for pulse compression both the structure as well as the learning algorithm associated with it need to be complex in nature. Accordingly in this paper a novel adaptive method is proposed by employing a complex valued fully connected cascaded (CFCC) neural network. For training this network, a new complex Levenberg–Marquardt (CLM) algorithm is derived and used for imparting effective training of its weights. The new CLM based CFCC (CFCC-CLM) model offers superior convergence performance with the least residual mean squared error during training phase compared to those provided by the multilayer perceptron (MLP) trained with complex domain backpropagation (CDBP) and CLM based methods. Further the comparison of peak signal-to-sidelobe ratio (PSR) under noisy and Doppler shift conditions of the proposed method exhibits best performance compared to those offered by the MLP-CDBP, MLP-CLM and the matched filter (MF) based methods.  相似文献   
64.
Structure of alpha-lytic protease complexed with its pro region   总被引:1,自引:0,他引:1  
While the majority of proteins fold rapidly and spontaneously to their native states, the extracellular bacterial protease alpha-lytic protease (alphaLP) has a t(1/2) for folding of approximately 2,000 years, corresponding to a folding barrier of 30 kcal mol(-1). AlphaLP is synthesized as a pro-enzyme where its pro region (Pro) acts as a foldase to stabilize the transition state for the folding reaction. Pro also functions as a potent folding catalyst when supplied as a separate polypeptide chain, accelerating the rate of alphaLP folding by a factor of 3 x 10(9). In the absence of Pro, alphaLP folds only partially to a stable molten globule-like intermediate state. Addition of Pro to this intermediate leads to rapid formation of native alphaLP. Here we report the crystal structures of Pro and of the non-covalent inhibitory complex between Pro and native alphaLP. The C-shaped Pro surrounds the C-terminal beta-barrel domain of the folded protease, forming a large complementary interface. Regions of extensive hydration in the interface explain how Pro binds tightly to the native state, yet even more tightly to the folding transition state. Based on structural and functional data we propose that a specific structural element in alphaLP is largely responsible for the folding barrier and suggest how Pro can overcome this barrier.  相似文献   
65.
Journal of Computer Science and Technology - The Slingshot interconnect designed by HPE/Cray is becoming more relevant in high-performance computing with its deployment on the upcoming exascale...  相似文献   
66.
Conventional derivative based learning rule poses stability problem when used in adaptive identification of infinite impulse response (IIR) systems. In addition the performance of these methods substantially deteriorates when reduced order adaptive models are used for such identification. In this paper the IIR system identification task is formulated as an optimization problem and a recently introduced cat swarm optimization (CSO) is used to develop a new population based learning rule for the model. Both actual and reduced order identification of few benchmarked IIR plants is carried out through simulation study. The results demonstrate superior identification performance of the new method compared to that achieved by genetic algorithm (GA) and particle swarm optimization (PSO) based identification.  相似文献   
67.
We had reported that a double-strand gap (ca. 300 bp long) in a duplex DNA is repaired through gene conversion copying a homologous duplex in a recB21 recC22 sbcA23 strain of Escherichia coli, as predicted on the basis of the double-strand break repair models. We have now examined various mutants for this repair capacity. (i) The recE159 mutation abolishes the reaction in the recB21C22 sbcA23 background. This result is consistent with the hypothesis that exonuclease VIII exposes a 3'-ended single strand from a double-strand break. (ii) Two recA alleles, including a complete deletion, fail to block the repair in this recBC sbcA background. (iii) Mutations in two more SOS-inducible genes, recN and recQ, do not decrease the repair. In addition, a lexA (Ind-) mutation, which blocks SOS induction, does not block the reaction. (iv) The recJ, recF, recO, and recR gene functions are nonessential in this background. (v) The RecBCD enzyme does not abolish the gap repair. We then examined genetic backgrounds other than recBC sbcA, in which the RecE pathway is not active. We failed to detect the double-strand gap repair in a rec+, a recA1, or a recB21 C22 strain, nor did we find the gap repair activity in a recD mutant or in a recB21 C22 sbcB15 sbcC201 mutant. We also failed to detect conservative repair of a simple double-strand break, which was made by restriction cleavage of an inserted linker oligonucleotide, in these backgrounds. We conclude that the RecBCD, RecBCD-, and RecF pathways cannot promote conservative double-strand break repair as the RecE and lambda Red pathways can.  相似文献   
68.

This paper presents an adaptive Improved Recycling Folded Cascode (IRFC) amplifier with improved gain, high slew rate, high phase margin and reduced power consumption. The proposed design is implemented using 180 nm technology with a supply voltage of 1.8 V and a capacitive load of 1 pF. The proposed design is compared with basic two stage op-amp, cascode amplifier and conventional recycling folded cascode amplifier (RFC). Analysis demonstrates that the flexible structure of IRFC with adaptive biasing shows an improvement in gain to 87.74 dB, approximately three times enhancement in slew rate to 53.8 V/µs when compared with the design specifications. The phase margin was observed to be 64.86°. The design also reports an increase in output swing. The gain increases to 109 dB when a cascode stage is added to the IRFC structure.

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69.
The effect of a chemical reaction on a free convection flow through a porous medium bounded by a vertical infinite surface has been studied. Velocity, temperature, and concentration profiles have been obtained for different values of parameters like the Grashof number, Prandtl number, and the chemical reaction parameter in the presence of homogeneous chemical reaction of first order. It is observed that the velocity and concentration increase during a generative reaction and decrease in a destructive reaction. The same is true for the behavior of the fluid temperature. The presence of the porous media diminishes the temperature.  相似文献   
70.

BaZrO3 doped (Na0.52K0.48)(Nb0.95Sb0.05)O3 ceramics were prepared using solid state route. The optimization of processing parameters like calcination temperature (800 °C), sintering temperature (1140 °C) and poling parameters (3 kV/mm at 120 °C/60 min) was carried out on base composition. Optimized parameters yielded a piezoelectric charge coefficient of 171 pC/N in composition having 4 mol% BaZrO3. Low temperature dielectric measurements and high temperature X-ray diffraction studies, along with structural refinement using Rietveld method were performed to ascertain the new found phenomenon. A castling-like phenomenon was observed in (1-x)(Na0.52K0.48)(Nb0.95Sb0.05)O3xBaZO3 (0.00?≤?x?≤?0.08) ceramics, where two phases interchanged their position. Also, BaZrO3 led to negative ageing behavior in these ceramics. Doping of BaZrO3 improved the electrical fatigue behavior and degraded the ferroelectric and thermal stability of ceramics.

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