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1.
S A Nagra 《Archivos latinoamericanos de nutrición》1989,39(1):9-16
A longitudinal study during the first year of life was conducted in Pakistani infants, to investigate the effect of feeding regimes on body weight. On an average, breast-fed infants showed better weight gain in the first six months. In the last six months of their first year, however, bottle-fed infants grew better. Breast-fed infants doubled their birth weight earlier than bottle- or combined-fed infants. 相似文献
2.
Central nervous system (CNS) damage occurs during retroviral infection in both man and animals. As a model of human disease, we studied the distribution and extent of CNS damage during retroviral infection with two molecularly cloned, neurotropic murine leukemia viruses. Both viruses mediate a spongiform encephalopathy involving predominantly the brainstem and spinal cord. During the course of disease, immune reactivity for synaptophysin (SYN) (to identify presynaptic elements) and microtubule-associated protein-2 (MAP-2) (to identify postsynaptic elements) were quantified using confocal laser microscopy. Immunostaining of SYN in the cerebral cortex (an area not exhibiting spongiform lesions) was similar in viral infected and age-matched control mice. However, compared to age matched controls, SYN staining in the brainstem (an area exhibiting spongiform lesions) of viral infected mice progressively declined during the course of disease. Quantitative analysis showed greater reduction of MAP-2 immunostaining in viral-infected mice compared to age-matched controls. In infected mice, both regions with and without spongiform lesions showed diminished MAP-2 staining. Widely distributed microscopic vacuolation of dendritic processes was observed in confocal preparations. These findings suggest primary dendritic damage in murine retroviral infection of the CNS similar to what has been described in human immunodeficiency virus-1 encephalitis. 相似文献
3.
The results of an experiment to measure digital signal forward echo impairment are compared with the calculated impairment obtained from measured cable characteristics. Modified theory gave good agreement in three out of four cases. 相似文献
4.
ABSTRACTFeature selection is an important task to improve the classifier’s accuracy and to decrease the problem size. A number of methodologies have been presented for feature selection problems using metaheuristic algorithms. In this paper, an improved self-adaptive inertia weight particle swarm optimisation with local search and combined with C4.5 classifiers for feature selection algorithm is proposed. In this proposed algorithm, the gradient base local search with its capacity of helping to explore the feature space and an improved self-adaptive inertia weight particle swarm optimisation with its ability to converge a best global solution in the search space. Experimental results have verified that the SIW-APSO-LS performed well compared with other state of art feature selection techniques on a suit of 16 standard data sets. 相似文献
5.
RM Nagra B Becher WW Tourtellotte JP Antel D Gold T Paladino RA Smith JR Nelson WF Reynolds 《Canadian Metallurgical Quarterly》1997,78(1-2):97-107
The influence of sampling time on the frequencies of micronuclei, centromere-positive micronuclei and chromosome nondisjunction was investigated in binucleated lymphocytes following treatment with a known clastogen (mitomycin C) or an aneuploidy-inducing agent (vincristine sulfate). Cytochalasin B (6 micrograms/ml) was added 44 h after mitogen stimulation and cultures were harvested 12, 28, 36 and 48 h thereafter. Micronucleated cells and micronuclei were significantly induced by the two treatments at all sampling times. Furthermore, in situ hybridization with an 'all centromeres' probe showed that vincristine-induced micronuclei were prevalently centromere-positive whereas in mitomycin C-treated cultures only a minor fraction of induced micronuclei contained the hybridization signals. Chromosome nondisjunction rates, as measured by in situ hybridization with chromosome 7- and 11-specific alphoid probes, significantly increased following vincristine treatment. Chromosome nondisjunction and total micronucleus frequencies were found to increase with time both in controls and in mutagen-treated cultures, whereas the percentage of centromere-positive micronuclei in the different treatments was not influenced by the sampling time. Our data suggest that even in the presence of 6 micrograms/ml cytochalasin B, the abnormal segregation of binucleated cells may contribute to the baseline level of micronuclei and influence the results obtained. The introduction of a short cytochalasin B treatment (between 12 and 28 h) in the cytokinesis-blocked micronucleus assay may avoid the cytochalasin B effect on micronucleus frequencies. 相似文献
6.
As an evolutionary computing technique, particle swarm optimization (PSO) has good global search ability, but the swarm can easily lose its diversity, leading to premature convergence. To solve this problem, an improved self-inertia weight adaptive particle swarm optimization algorithm with a gradient-based local search strategy (SIW-APSO-LS) is proposed. This new algorithm balances the exploration capabilities of the improved inertia weight adaptive particle swarm optimization and the exploitation of the gradient-based local search strategy. The self-inertia weight adaptive particle swarm optimization (SIW-APSO) is used to search the solution. The SIW-APSO is updated with an evolutionary process in such a way that each particle iteratively improves its velocities and positions. The gradient-based local search focuses on the exploitation ability because it performs an accurate search following SIW-APSO. Experimental results verified that the proposed algorithm performed well compared with other PSO variants on a suite of benchmark optimization functions. 相似文献
7.
Mariano Ceccato Mila Dalla Preda Jasvir Nagra Christian Collberg Paolo Tonella 《Automated Software Engineering》2009,16(2):235-261
Network applications often require that a trust relationship is established between a trusted host (e.g., the server) and
an untrusted host (e.g., the client). The remote entrusting problem is the problem of ensuring the trusted host that whenever
a request from an untrusted host is served, the requester is in a genuine state, unaffected by malicious modifications or
attacks.
Barrier slicing helps solve the remote entrusting problem. The computation of the sensitive client state is sliced and moved
to the server, where it is not possible to tamper with it. However, this solution might involve unacceptable computation and
communication costs for the server, especially when the slice to be moved is large. In this paper, we investigate the trade-off
between security loss and performance overhead associated with moving only a portion of the barrier slice to the server and
we show that this trade-off can be reduced to a multi-objective optimization problem. We describe how to make decisions in
practice with reference to a case study, for which we show how to choose among the alternative options. 相似文献
8.
The study was conducted to improve the nutritional value of Mung (Vigna radiata) by supplementation with different kinds of meat. Diets were prepared using raw and cooked Mung and then cooked Mung was supplemented with poultry, mutton and beef at 10, 15, and 20 percent levels. Nutritional value of Mung was determined by chemical analysis as well as by rat assay. Mung had 25 percent protein and minor losses were observed during cooking. It had 1.21 percent lysine which was reduced by 43 percent on cooking. Other amino acids also showed losses during cooking. The Protein Efficiency Ratio (PER) of diet containing Mung was significantly reduced on cooking (1.86 vs 1.40). On the contrary cooking resulted in some improvement of Net Protein utilization (NPU) and True Digestibility (TD) of the Mung based diets. Twenty percent level of different meats showed better results in terms of PER, NPU and TD. 相似文献
9.
An explicit finite-difference time-domain (FDTD) scheme for wave propagation in certain kinds of nonlinear media such as saturable absorbers and gain layers in lasers is proposed here. This scheme is an extension of the auxiliary differential equation FDTD approach and incorporates rate equations that govern the time-domain dynamics of the atomic populations in the medium. For small signal intensities and slowly varying pulses, this method gives the same results as frequency-domain methods using the linear susceptibility function. Population dynamics for large signal intensities and the transient response for rapidly varying pulses in two-level (absorber) and four-level (gain) atomic media are calculated to demonstrate the advantages of this approach 相似文献
10.
Energy utilization was studied in human volunteers using different diets containing wheat flour supplemented by groundnut (Arachis hypogaea), "masur" (Lens culinaris), mung (Phaseolus aureus) and gram (Cicer arietinum) flour. Digestible and metabolizable energies were determined for all the experimental diets. An improved energy digestibility was observed when wheat flour was supplemented with groundnut flour, and groundnut flour plus gram flour, i.e. 93.35 and 89.48%, respectively. Percent digestibility of energy for the other two experimental diets was 81.07% when wheat flour was supplemented with groundnut and "masur" flour. It was further depressed to 77.87% when wheat flour was supplemented with groundnut and mung flour. 相似文献