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171.
Visual area V4 is a midtier cortical area in the ventral visual pathway. It is crucial for visual object recognition and has been a focus of many studies on visual attention. However, there is no unifying view of V4's role in visual processing. Neither is there an understanding of how its role in feature processing interfaces with its role in visual attention. This review captures our current knowledge of V4, largely derived from electrophysiological and imaging studies in the macaque monkey. Based on recent discovery of functionally specific domains in V4, we propose that the unifying function of V4 circuitry is to enable selective extraction of specific functional domain-based networks, whether it be by bottom-up specification of object features or by top-down attentionally driven selection. 相似文献
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Hyun-Myung Oh Yong-Joon Cho Byung Kwon Kim Jung-Hye Roe Sa-Ouk Kang Baek Hie Nahm Gajin Jeong Hong-Ui Han Jongsik Chun 《Journal of bacteriology》2010,192(14):3844-3845
Leuconostoc kimchii IMSNU 11154, isolated from kimchi, a traditional Korean fermented food, is known to be an important antimicrobial lactic acid bacterium with probiotic potential. Here we announce the complete genome sequence of L. kimchii IMSNU 11154 consisting of a 2,101,787-bp chromosome and five plasmids. The strain has genes for dextran formation from sucrose and for mannitol formation from fructose. Antimicrobial and antioxidative functions of L. kimchii IMSNU 11154 could be attributed to a leucosin B-like peptide and multiple enzymes to reduce hydrogen peroxide and oxidized thiols, respectively.Kimchi is a traditional Korean pickled vegetable dish with varied seasonings, and it is known to be an important source of vitamins, minerals, and dietary fiber as well as a good dietary source of lactic acid bacteria (LAB) for humans (2, 3). An exopolysaccharide (EPS)-producing LAB, designated IMSNU 11154, was isolated from kimchi made of cabbage and subsequently classified as a novel species, Leuconostoc kimchii (6). The strain and its culture broth showed antimicrobial activities against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Bacillus cepacia, Candida albicans, and Aspergillus niger. Here we report the genome sequence of Leuconostoc kimchii IMSNU 11154 using a whole-genome shotgun sequencing strategy (4). The complete sequences of one chromosome and five plasmids were obtained. The circular chromosome of strain IMSNU 11154 was 2,101,787 bp in length (37.9% G+C), and the five plasmids were LkipL48 (3,196 bp; 37.1% G+C), LkipL4701 (21,055 bp; 34.3% G+C), LkipL4704 (23,285 bp; 35.6% G+C), LkipL4719 (21,924 bp; 39.1% G+C), and LkipL4726 (29,616 bp; 35.5% G+C). The number of predicted open reading frames (ORFs) is 2,205, covering 89.5% (1,880,952 bp) of the genome. Noncoding RNA regions were identified as 68 tRNAs and 4 copies of rRNA operons. A small gene encoding a leucosin B-like peptide was identified.Strain IMSNU 11154 was missing the fructose 1,6-bisphosphatase enzyme of the Embden-Meyerhof-Parnas pathway and transaldolase of the 6-phosphogluconate/phosphoketolase pathway. Tricarboxylic cycle enzymes were also absent, except for cytochrome oxidase bd-I subunits. The strain metabolized sucrose by invertase, sucrose phosphorylase, and dextransucrase. Formation of EPS and fructose from sucrose by dextransucrase could enhance the probiotic function as well as improve the taste and flavor of kimchi. Strain IMSNU 11154 had a mannitol dehydrogenase gene (mdh) identical to mdh of Leuconostoc mesenteroides (1). By producing mannitol, it maintains its turgor and stabilizes membrane lipids and proteins at low water activity as well as scavenges free reactive oxygen radicals as previously observed for mannitol fermenters (10). Like other Leuconostoc spp., strain IMSNU 11154 does not bear any catalase or superoxide dismutase (SOD) enzymes but has six thioredoxins and four thioredoxin reductases that were shown to be important in coping with acid and oxidative stress (9, 11). Harboring thioredoxin systems on plasmids is a common feature for both L. kimchii IMSNU 11154 and Leuconostoc citreum KM20 (7). Glutathione protected some lactic acid bacteria against oxidative stress (8), but gamma-glutamylcysteine (γ-GC) is the major low-molecular-weight thiol in Leuconostoc spp., including IMSNU 11154 (5). Genes for γ-GC synthesis and reduction are present in strain IMSNU 11154 (5), and there are genes for putative peroxiredoxins that can reduce hydrogen peroxide via small thiols or thioredoxins. Thus, multiple antioxidative systems reduce thiols in strain IMSNU 11154.In conclusion, the genome of Leuconostoc kimchii IMSNU 11154 revealed that its carbohydrate metabolism has adapted to the formation of dextran, fructose, and mannitol from sucrose. The antimicrobial activity of strain IMSNU 11154 could be due to a leucosin B-like peptide, and it contains multiple antioxidative systems to manage acid and oxidative stresses independent of SOD and catalase. 相似文献
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Tanja V.E. Kral April C. Kabay Liane S. Roe Barbara J. Rolls 《Obesity (Silver Spring, Md.)》2010,18(3):521-527
Increasing the portion size of energy‐dense entrées has been shown to increase children's energy intake during a meal. It remains to be investigated whether serving larger portions to children can be used to promote intake of more healthful foods, such as fruits and vegetables (F&V). The aim of the present study was to examine the effects of increasing the portion size of F&V side dishes on children's intake. Forty‐three children (22 boys, 21 girls), aged 5–6 years, were served dinner once a week for 2 weeks. Each dinner consisted of pasta with tomato sauce, three F&V side dishes (broccoli, carrots, and applesauce), and milk. The portion size of the F&V was doubled between experimental conditions whereas the size of the pasta remained constant. Doubling the portion size of the side dishes resulted in a 43% increase in children's intake of the fruit side dish (P = 0.001), but did not affect children's intake of the two vegetable side dishes (P > 0.60). Further, when the portion size of F&V side dishes was doubled, children ate significantly less of the pasta (P = 0.04). The difference in meal energy intake between portion size conditions (19.5 ± 16.3 kcal) was not significant (P = 0.24). Although more studies are needed to understand whether increases in portion size can influence vegetable intake, children did eat more in response to a large quantity of a preferred low energy‐dense fruit side dish at meals. Thus variations in portion size can be used strategically to help children achieve the recommended intake of fruits. 相似文献
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Land-use practices surrounding a wetland may be as important for maintaining wildlife populations as the wetland itself. Although imperiled species may appear to be more impacted than ubiquitous species from changes in the landscape surrounding wetlands, studies of common wetland species are useful for conservation because they provide insight into why some species persist despite landscape changes. We therefore investigated the relationship between connectivity, measured as the wetland distance to other wetlands; connectivity quality, implied by wetland distance to roads and forest area within 30, 125, 250, 500 and 1000 m buffer zones around the wetland; and patch size as indicated by wetland size with northern watersnake Nerodia sipedon sipedon abundance. Our results suggest that both upland and wetland characteristics influence the abundance of N. s. sipedon , as wetland size and wetland connectivity to other wetlands were significantly associated with abundance. Abundance was positively correlated with increasing wetland size and wetland connectivity. We were not able to find a significant relationship between abundance and connectivity quality, and wetland distance to road or forest area within 30, 125, 250, 500 and 1000 m buffer zones. We conclude that wetland conservation should focus on wetland complexes as well as individual wetlands. In addition, common wetland species such as the northern watersnake do not appear to be negatively impacted by modifications to nearby terrestrial habitats, such as deforestation and roads, and may benefit from the creation of larger, permanent wetlands. 相似文献
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