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101.
This paper proposed a novel bionic selective visual attention mechanism to quickly select regions that contain salient objects to reduce calculations. Firstly, lateral inhibition filtering, inspired by the limulus’ ommateum, is applied to filter low-frequency noises. After the filtering operation, we use Artificial Bee Colony (ABC) algorithm based selective visual attention mechanism to obtain the interested object to carry through the following recognition operation. In order to eliminate the camera motion influence, this paper adopted ABC algorithm, a new optimization method inspired by swarm intelligence, to calculate the motion salience map to integrate with conventional visual attention. To prove the feasibility and effectiveness of our method, several experiments were conducted. First the filtering results of lateral inhibition filter were shown to illustrate its noise reducing effect, then we applied the ABC algorithm to obtain the motion features of the image sequence. The ABC algorithm is proved to be more robust and effective through the comparison between ABC algorithm and popular Particle Swarm Optimization (PSO) algorithm. Except for the above results, we also compared the classic visual attention mechanism and our ABC algorithm based visual attention mechanism, and the experimental results of which further verified the effectiveness of our method.  相似文献   
102.
Alfalfa (Medicago sativa; =M. sativa ssp. sativa) in Lithuania is sown as albuminous forage for cattle due to favourable climatic condition. Over many generations, alfalfa plants have escaped from cultivation fields into natural ecosystems and established wild populations. We collected and analyzed individuals from seventeen wild populations of M. sativa. Using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analyses, 117 RAPD and 64 ISSR reproducible and highly polymorphic (90.8% for RAPD and 86.3% for ISSR) loci were established. AMOVA showed a high genetic differentiation of M. sativa populations for both types of DNA markers utilized. According to RAPD markers, the genetic variability among populations was 63.1% and 57.0% when ISSR markers were used. Taken together, these results demonstrate that wild populations of M. sativa possess a high potential of genetic variability, that could potentially result in colonization of natural ecosystems. The UPGMA cluster analysis also showed that the DNA markers discovered in this study can distinguish between M. sativa and M. falcata (=M. sativa ssp. falcata) populations and therefore may be used to study the genetic impact of M. sativa on the native populations of M. falcata.  相似文献   
103.
104.
Erythropoietin (EPO) has multiple biological functions, including the modulation of glucose metabolism. However, the mechanisms underlying the action of EPO are still obscure. This study is aimed at investigating the potential mechanisms by which EPO improves glucose tolerance in an animal model of type 2 diabetes. Male C57BL/6 mice were fed with high-fat diet (HFD) for 12 weeks and then treated with EPO (HFD-EPO) or vehicle saline (HFD-Con) for two week. The levels of fasting blood glucose, serum insulin and glucose tolerance were measured and the relative levels of insulin-related phosphatidylinositol 3-kinase (PI3K)/Akt, insulin receptor (IR) and IR substrate 1 (IRS1) phosphorylation were determined. The levels of phosphoenolpyruvate carboxykinase (PEPCK), glucose-6- phosphatase (G6Pase), toll like receptor 4 (TLR4), tumor necrosis factor (TNF)-α and IL-6 expression and nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK), extracellular-signal-regulated kinase (ERK) and p38 MAPK activation in the liver were examined. EPO treatment significantly reduced the body weights and the levels of fasting blood glucose and serum insulin and improved the HFD-induced glucose intolerance in mice. EPO treatment significantly enhanced the levels of Akt, but not IR and IRS1, phosphorylation, accompanied by inhibiting the PEPCK and G6Pase expression in the liver. Furthermore, EPO treatment mitigated the HFD-induced inflammatory TNF-α and IL-6 production, TLR4 expression, NF-κB and JNK, but not ERK and p38 MAPK, phosphorylation in the liver. Therefore, our data indicated that EPO treatment improved glucose intolerance by inhibiting gluconeogenesis and inflammation in the livers of HFD-fed mice.  相似文献   
105.
In this study, we describe a novel porcine parechovirus-like virus (tentatively named PLV-CHN) from healthy piglets in China using 454 high-throughput sequencing. The complete genome of the virus comprises 6832 bp, encoding a predicted polyprotein of 2132 amino acids that is most similar to Ljungan virus (32% identity). A similar virus that belongs to a novel Picornaviridae genus, named swine pasivirus 1 (SPaV-1), was reported during the preparation of this paper. Sequence analysis revealed that PLV-CHN and SPaV1 shared 82% nucleotide identity and 89% amino acid identity. Further genomic and phylogenetic analyses suggested that both SPaV1 and PLV-CHN shared similar genomic characteristics and belong to the same novel Picornaviridae genus. A total of 36 (20.0%) fecal samples from 180 healthy piglets were positive for PLV-CHN by RT-PCR, while no fecal samples from 100 healthy children and 100 children with diarrhea, and no cerebrospinal fluid samples from 196 children with suspected viral encephalitis, was positive for the virus. However, Western blot and enzyme-linked immunosorbent assays using recombinant PLV-CHN VP1 polypeptide as an antigen showed a high seroprevalence of 63.5% in the healthy population. When grouped by age, the antibody-positivity rates showed that the majority of children under 12 years of age have been infected by the virus. It was suggested that PLV-CHN, SPaV1, or an as-yet-uncharacterized virus can infect humans early in life. Thus, investigation of the role of this novel virus is vital.  相似文献   
106.
107.
The effects of drought on plant growth and development are occurring as a result of climate change and the growing scarcity of water resources. Hippophae rhamnoides has been exploited for soil and water conservation for many years. However, the outstanding drought‐resistance mechanisms possessed by this species remain unclear. The protein, physiological, and biochemical responses to medium and severe drought stresses in H. rhamnoides seedlings are analyzed. Linear decreases in photosynthesis rate, transpiration rate, and the content of indole acetic acid in roots, as well as a linear increase in the contents of abscisic acid, superoxide dismutase, glutathione reductase, and zeatin riboside in leaves are observed as water potential decreased. At the same time, cell membrane permeability, malondialdehyde, stomatal conductance, water use efficiency, and contents of zeatin riboside in roots and indole acetic acid in leaves showed nonconsistent changes. DIGE and MS/MS analysis identified 51 differently expressed protein spots in leaves with functions related to epigenetic modification and PTM in addition to normal metabolism, photosynthesis, signal transduction, antioxidative systems, and responses to stimuli. This study provides new insights into the responses and adaptations in this drought‐resistant species and may benefit future agricultural production.  相似文献   
108.
After an extensive vaccination policy, Japanese encephalitis (JE) was nearly eliminated since the mid-1980s in South Korea. Vaccination in children shifted the affected age of JE patients from children to adults. However, an abrupt increase in JE cases occurred in 2010, and this trend has continued. The present study aimed to investigate the prevalence of neutralizing antibodies to the JE virus (JEV) among high-risk age groups (≥40 years) in South Korea. A plaque reduction neutralization test was conducted to evaluate the prevalence of neutralizing antibodies to JEV in 945 subjects within four age groups (30–39, 40–49, 50–59, and 60–69 years) in 10 provinces. Of the 945 enrolled subjects, 927 (98.1%) exhibited antibodies against JEV. No significant differences were found in the prevalence of neutralizing antibodies according to sex, age, or occupation. However, there were significant differences in the plaque reduction rate according to age and occupation; oldest age group had a higher reduction rate, and subjects who were employed in agriculture or forestry also had a higher value than the other occupations. We also found that three provinces (Gangwon, Jeonnam, and Gyeongnam) had a relatively lower plaque reduction rate than the other locations. In addition, enzyme-linked immunosorbent assays were conducted to determine recent viral infections and 12 (2.2%) subjects were found to have been recently infected by the virus. In conclusion, the present study clearly indicated that the prevalence of neutralizing antibodies has been maintained at very high levels among adult age groups owing to vaccination or natural infections, or both. In the future, serosurveillance should be conducted periodically using more representative samples to better understand the population-level immunity to JE in South Korea.  相似文献   
109.
110.
Huntington’s disease (HD) is caused by an expansion of the trinucleotide poly (CAG) tract located in exon 1 of the huntingtin (Htt) gene leading to progressive neurodegeneration in selected brain regions, and associated functional impairments in motor, cognitive, and psychiatric domains. Since the discovery of the gene mutation that causes the disease, mouse models have been developed by different strategies. Recently, a new model, the zQ175 knock-in (KI) line, was developed in an attempt to have the Htt gene in a context and causing a phenotype that more closely mimics HD in humans. The behavioral phenotype was characterized across the independent laboratories and important features reminiscent of human HD are observed in zQ175 mice. In the current study, we characterized the zQ175 model housed in an academic laboratory under reversed dark-light cycle, including motor function, in vivo longitudinal structural MRI imaging for brain volume, MRS for striatal metabolites, neuropathology, as well as a panel of key disease marker proteins in the striatum at different ages. Our results suggest that homozygous zQ175 mice exhibited significant brain atrophy before the motor deficits and brain metabolite changes. Altered striatal medium spiny neuronal marker, postsynaptic marker protein and complement component C1qC also characterized zQ175 mice. Our results confirmed that the zQ175 KI model is valuable in understanding of HD-like pathophysiology and evaluation of potential therapeutics. Our data also provide suggestions to select appropriate outcome measurements in preclinical studies using the zQ175 mice.  相似文献   
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