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Paddy and Water Environment - In this article, we examined the value of the traditional Japanese flood control measure that uses a discontinuous levee (kasumitei). By avoiding the use of...  相似文献   
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Background: The present study investigated the functional maturity of oligodendrocyte derived from rat bone marrow stromal cells (BMSC). Methods: The BMSC were isolated from female Sprague-Dawley rats and evaluated for different markers, such as fibronectin, CD106, CD90, Oct-4 and CD45. Transdifferentiation of OLC from BMSC was obtained by exposing the BMSC to DMSO and 1 µM all-trans-retinoic acid during the pre-induction stage and then induced by heregulin (HRG), platelet-derived growth factor AA (PDGFR-α), fibroblast growth factor and T3. The neuroprogenitor cells (NPC) were evaluated for nestin, neurofilament 68, neurofilament 160 and glial fibrillary acidic protein gene expression using immunocytochemistry. The OLC were assessed by immunocytochemistry for O4, oligo2, O1 and MBP marker and gene expression of PDGFR-α was examined by RT-PCR. Results: Our results showed that the fibronectin, CD106, CD90, CD45 and Oct-4 were expressed after the fourth passage. Also, the yield of OLC differentiation was about 71% when using the O1, O4 and oligo2 markers. Likewise, the expression of PDGFR-α in pre-oligodendrocytes was noticed, while MBP expression was detected in oligodendrocyte after 6 days of the induction. Conclusion: The conclusion of the study showed that BMSC can be induced to transdifferentiate into mature OLC. Key Words: Bone marrow stromal cell, Triiodothyronine, Platelet-derived growth factor α  相似文献   
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Background: The primary phase of traumatic spinal cord injury (SCI) starts by a complex local inflammatory reaction such as secretion of pro-inflammatory cytokines from microglia and injured cells that substantially contribute to exacerbating pathogenic events in secondary phase. Valproic acid (VPA) is a histone deacetylase inhibitor. Acetylation of histones is critical to cellular inflammatory and repair processes. Methods: In this study, rats were randomly assigned to five experimental groups (laminectomy, untreated, and three VPA-treated groups). For SCI, severe contusion was used. In treated groups, VPA was administered intraperitoneally at doses of 100, 200 and 400 mg/kg daily three hours after injury for 7 days. To compare locomotor improvement among experimental groups, behavioral assessments were performed by the Basso, Beattie and Bresnahan (BBB) rating scale. The expression of neurotrophins was evaluated by RT-PCR and real-time PCR. Results: VPA administration increased regional brain-derived neurotrophic factor and glial cell-derived neurotrophic factor mRNA levels. Local inflammation and the expression of the lysosomal marker ED1 by activated macrophages/microglial cells were reduced by VPA and immunoreactivity of acetylated histone and microtubule-associated protein were increased. Conclusion: The results showed a reduction in the development of secondary damage in rat spinal cord trauma with an improvement in the open field test (BBB scale) with rapid recovery.Key Words: Inflammation, Epigenetics, Valproic acid (VPA)  相似文献   
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Feeding systems such as grazing affect the fatty acid profile of bovine milk fat. In addition, milk fat is formed as the product of fatty acid metabolism in cow bodies before being secreted into milk. However, how grazing influences milk fatty acid profile through the metabolism has not been completely characterized. When fatty acid concentrations in Holstein milk were compared between grazing and non‐grazing periods, α‐linolenic acid was significantly higher in the grazing period than in the non‐grazing period. This could be explained with an increase in α‐linolenic acid feeding with grazing. α‐linolenic acid had a linear positive correlation with conjugated linoleic acid (9c,11t‐18:2) (CLA) and vaccenic acid (VA) during the grazing period, whereas CLA had higher correlation with linoleic acid rather than with α‐linolenic acid during the non‐grazing period. These data indicate that the high content of dietary α‐linolenic acid affects CLA and VA formation in milk of grazing periods via α‐linolenic acid metabolism into VA.  相似文献   
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We derived a formula for estimating the relationship between stem carbon weight and stem volume, which was calculated from DBH and tree height using a combination of stem analysis and soft X-ray densitometry. The results indicate carbon weight in a 33-year-old coastal Japanese black pine (Pinus thunbergii) forest is approximately 68,186 kg ha?1 in Yamagata Prefecture and 38,253 kg ha?1in a 42-year-old black pine forest in Hokkaido Prefecture, Japan. Also, age-related changes in the stem density following oven-drying of samples of black pine trees are small: the oven-dried density (hereafter “density”) of black pine trees in the two locations mentioned above were 425.6 (kg m?3) and 523.2 (kg m?3) respectively, which is comparable to the density (converted from basic density) of black pine of Land Use, Land-Use Change and Forestry (LULUCF) (533 kg m?3). When compared with the carbon weight by the oven-dried density of LULUCF, the carbon weights calculated from each density were 27 % lower in Yamagata and 6 % lower in Hokkaido. This difference directly affects carbon weight for large-scale estimation and thus can create an error at a regional scale. This methodology can contribute to the management of forests acting as carbon sinks.  相似文献   
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Crusting and hardsetting phenomena are major problems in the emergence of delicate seedlings through weak structured soils. When a hard layer develops on the surface, it can retard seedling emergence and the trapped seedlings may perish unless the hard layer is broken or weakened. The development of natural desiccation cracks on the soil surface creates a route by which seedlings can emerge. The work conducted by the same authors suggested that the compaction of soil strips over the seed rows creates longitudinal cracks along the planting lines to improve seedling emergence. This study is an attempt to develop an alternative method to create the linear cracks using the effect of surface micro‐relief. Preliminary experiments showed that the creation of small furrows (50 mm deep) on the soil surface caused the appearance of cracks mainly at the bottom of the furrows. Monitoring the movement of aggregates during drainage, where small depressions are formed on the soil surface, revealed that the aggregates on either side of the turning point of the depression move in opposite directions as a result of the greater water tension developed in the ridges causing development of cracks at the turning point. Laboratory experiments indicated that the radius of curvature at the turning point of the depression, the spacing between depressions and the shape of ridges either side of the depressions are key factors influencing crack development at the bottom of depressions. A field experiment in semi‐arid central Iran confirmed the feasibility of the technique by the use of a backward raked shaper to develop small ridge and furrows on the surface of the seedbed which resulted in the creation of longitudinal cracks in the furrow bottoms, coincident with the seed row. An outline design of a press wheel is given.  相似文献   
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Sonmez  Fatih  Gunesli  Zuhal  Demir  Taki  Cıkrıkcı  Kubra  Ergun  Adem  Gencer  Nahit  Arslan  Oktay 《Erwerbs-Obstbau》2022,64(2):145-153

Total anthocyanins were extracted from eleven sweet cherry cultivars grown in Sakarya, Turkey. In vitro inhibition effects of extracted total anthocyanins on purified carbonic anhydrase I and II were investigated by using CO2 as a substrate. The results showed that all extracted total anthocyanins inhibited the hCA I and hCA II enzyme activities. Among all cultivars, ‘Merton Premier’ was found to be the most active one against both hCA I (IC50?=?0.83?µg/mL) and hCA II (IC50?=?1.16?µg/mL). Additionally, the DPPH activities of the extracts were investigated as antioxidant properties. The results exhibited that ‘Churchill’ and ‘Merton Premier’ have high antioxidant activity with 74.102% and 73.503% DPPH activity, respectively.

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ABSTRACT: BACKGROUND: The positive relationship between habitat area and species number is considered a fundamental rule in ecology. This relationship predicts that the link number of species interactions increases with habitat area, and structure is related to habitat area. Biological invasions can affect species interactions and area relationships. However, how these relationships change at different spatial scales has remained unexplored. We analysed understory plant-pollinator networks in seven temperate forest sites at 20 spatial scales (radius 120-2020 m) to clarify scale-associated relationships between forest area and plant-pollinator networks. RESULTS: The pooled data described interactions between 18 plant (including an exotic) and 89 pollinator (including an exotic) species. The total number of species and the number of interaction links between plant and pollinator species were negatively correlated with forest area, with the highest correlation coefficient at radii of 1520 and 1620 m, respectively. These results are not concordant with the pattern predicted by species-area relationships. However, when associations with exotic species were excluded, the total number of species and the number of interaction links were positively correlated with forest area (the highest correlation coefficient at a radius of 820 m). The network structure, i.e., connectance and nestedness, was also related to forest area (the highest correlation coefficients at radii of 720-820 m), when associations with exotics were excluded. In the study area, the exotic plant species Alliaria petiolata, which has invaded relatively small forest patches surrounded by agricultural fields, may have supported more native pollinator species than initially expected. Therefore, this invasive plant may have altered the original relationships between forest area and plant-pollinator networks. CONCLUSIONS: Our results demonstrate scale-dependent effects of forest area on the size and structure of plant-pollinator networks. We also suggest that a single exotic plant species can impact plant-pollinator networks, even in temperate continental habitats.  相似文献   
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