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1.
There are few reliable data sets to inspire confidence in policymakers that soil organic carbon (SOC) can be measured on farms. We worked with farmers in the Tamar Valley region of southwest England to select sampling sites under similar conditions (soil type, aspect and slope) and management types. Topsoils (2–15 cm) were sampled in autumn 2015, and percentage soil organic matter (%SOM) was determined by loss on ignition and used to calculate %SOC. We also used the stability of macroaggregates in cold water (WSA) (‘soil slaking’) as a measure of ‘soil health’ and investigated its relationship with SOC in the clay‐rich soils. %SOM was significantly different between management types in the order woodland (11.1%) = permanent pasture (9.5%) > ley‐arable rotation (7.7%) = arable (7.3%). This related directly to SOC stocks that were larger in fields under permanent pasture and woodland compared with those under arable or ley‐arable rotation whether corrected for clay content (F = 8.500, p < .0001) or not (F = 8.516, p < .0001). WSA scores were strongly correlated with SOC content whether corrected for clay content (SOCadj R2 = .571, p < .0001) or not (SOCunadj R2 = 0.490, p = .002). Time since tillage controlled SOC stocks and WSA scores, accounting for 75.5% and 51.3% of the total variation, respectively. We conclude that (1) SOC can be reliably measured in farmed soils using accepted protocols and related to land management and (2) WSA scores can be rapidly measured in clay soils and related to SOC stocks and soil management.  相似文献   
2.
Myoblast differentiation is an essential process during skeletal muscle development. C2 C12 myoblast is a commonly used experimental model to study muscle cell differentiation in vitro. Dehydrogenase/reductase(SDR family) member 3(DHRS3) is a highly conserved member in short-chain alcohol dehydrogenase/reductase superfamily and has been shown to be involved in the metabolism of retinol. Previous experimental results showed that the expression of DHRS3 increased significantly during the differentiation of myoblasts differentiation. However, the effect of DHRS3 on mouse muscle cell differentiation was unclear. The objective of current study was to determine if DHRS3 affected muscle cell differentiation, and if DHRS3 was involved in muscle regeneration. Protein expression was determined by western blot and immunofluorescence analysis. The activation and inhibition of DHRS3 increased and decreased C2 C12 myoblast differentiation respectively, which indicated that DHRS3 could affect C2 C12 myoblast differentiation. DHRS3 expression was significantly changed during muscle regeneration, with the regeneration of muscle injury, the expression of DHRS3 tended to increase first and then decrease. It suggested that DHRS3 might be involved in muscle regeneration. In summary, this study confirmed the involvement of DHRS3 in C2 C12 myoblast differentiation and mouse skeletal muscle regeneration and provided a theoretical basis for further elucidating the molecular mechanism of muscle development.  相似文献   
3.
为研究树脂对改性材性能的影响,采用2种不同工艺合成三聚氰胺-脲醛树脂(MUF),测试了树脂的相关性能。结果表明,不同合成工艺路线下制备的 MUF 树脂在固体含量、粘度、固化时间、游离甲醛含量间存在显著差异。最终树脂的分子结构类型相似性极高,但相同结构组分在不同树脂中所占比例各有差异。羟甲基基团在MUF2中所占比例高,而亚甲基桥键及醚键在MUF1中含量高。MUF1改性材的增重率(weight percent gain,WPG)值更大,但MUF2改性材的抗溶胀性(anti-swelling efficiency,ASE)和体积膨胀率(bulking rates,B)更高,MUF2改性材的尺寸稳定性更好。  相似文献   
4.
为研究不同品种余甘子果实维生素C含量差异和余甘子果实维生素C积累规律,本研究以6个品种余甘子果实为试材,比较不同时期余甘子果实维生素C含量的差异,描绘维生素C积累动态曲线。结果表明,余甘子果实维生素C含量丰富,适宜作为食品加工和保健品的开发利用;其中秋白品种维生素C含量最高,适宜作为加工和遗传育种的原材料;余甘子果实作为加工原材料适宜采收期为10月20日左右;维生素C 的积累分为快速积累阶段,缓慢积累阶段,下降阶段,稳定阶段4个阶段。  相似文献   
5.
AIM: To investigate the expression and roles of family with sequence similarity 3, member C (FAM3C) in oral squamous-cell carcinoma cells. METHODS: The mRNA and protein expression levels of FAM3C in dysplastic oral keratinocyte (DOK) and oral squamous-cell carcinoma WSU-HN6 cells were detected by RT-qPCR and Western blot. The WSU-HN6 cells were treated with siFAM3C or FAM3C antibody. After 24, 48 and 72 h, the viability of WSU-HN6 cells was measured by CCK-8 assay, and the activation of protein kinase B (Akt) was detected by Western blot. Adenovirus was used to mediate over-expression of FAM3C in the DOK cells. The DOK cell viability was measured by CCK-8 assay after adenovirus infection for 24, 48 and 72 h, and the activation of Akt was detected by Western blot. RESULTS: Compared with the DOK cells, the mRNA and protein levels of FAM3C were significantly increased in the WSU-HN6 cells (P<0.05). The viability of WSU-HN6 cells transfected with siFAM3C was significantly inhibited at 48 h and 72 h (P<0.05). siFAM3C treatment inhibited the activation of Akt (P<0.05). FAM3C antibody treatment also suppressed the viability of the WSU-HN6 cells at 48 h and 72 h and the activation of Akt (P<0.05). Over-expression of FAM3C in the DOK cells promoted the cell viability at 48 h and 72 h and activated Akt (P<0.05). CONCLUSION: FAM3C might promote oral squamous-cell carcinoma cell growth by activating Akt.  相似文献   
6.
【目的】深度学习在图像分类方面效果显著,但对机器的硬件配置要求高,将深度学习的技术应用于作物分类的同时,降低客户端的IT成本,开发基于深度学习服务的遥感影像农作物分类系统。【方法】系统采用C/S架构,服务器端部署Caffe的深度学习框架,通过PaaS提供计算服务,统一处理客户端模型训练、影像分类等任务;客户端提供用户界面,负责数据输入、结果解析和可视化操作;客户端和服务器之间通过异步RPC实现网络通信,利用FTP进行数据的上传和下载;考虑到农作物分类在实际应用中的时效性,系统还提供了一个简化的Alexnet模型,在保证分类精度的前提下加速了模型的收敛速度。【结果】通过对采集的428144个农作物样本数据集的应用表明,服务器训练的时间比单机训练缩短了近3倍,该系统不仅能够快速地完成深度学习模型训练的任务,还能实时准确得到遥感影像的农作物分类结果。【结论】该研究进一步推动了深度学习在农业分类方面的应用,同时为遥感技术在农业应用中的发展、农作物面积统计工作和对农业资源进行优化配置提供了重要的科学指导。  相似文献   
7.
"梦茗"系从安徽省岳西县来榜镇优良地方群体种中采用单株选育法育成的适制绿茶新品种。经安徽省内品比、推广示范和全国区试,发现"梦茗"物候期与福鼎大白茶相当,属早生种。品质优异,全国区试3个点感官审评总分均高于对照;内含物含量高,氨基酸含量4.9%、茶多酚总量26.9%、水浸出物总量40%。产量高,品比试验高于福鼎大白茶26.45%,全国区试产量与对照相当。抗旱能力强,抗寒能力与对照相当。  相似文献   
8.
Intensive vegetable production in greenhouses has rapidly expanded in China since the 1990s and increased to 1.3 million ha of farmland by 2016, which is the highest in the world. We conducted an 11‐year greenhouse vegetable production experiment from 2002 to 2013 to observe soil organic carbon (SOC) dynamics under three management systems, i.e., conventional (CON), integrated (ING), and intensive organic (ORG) farming. Soil samples (0–20 and 20–40 cm depth) were collected in 2002 and 2013 and separated into four particle‐size fractions, i.e., coarse sand (> 250 µm), fine sand (250–53 µm), silt (53–2 µm), and clay (< 2 µm). The SOC contents and δ13C values of the whole soil and the four particle‐size fractions were analyzed. After 11 years of vegetable farming, ORG and ING significantly increased SOC stocks (0–20 cm) by 4008 ± 36.6 and 2880 ± 365 kg C ha?1 y?1, respectively, 8.1‐ and 5.8‐times that of CON (494 ± 42.6 kg C ha?1 y?1). The SOC stock increase in ORG at 20–40 cm depth was 245 ± 66.4 kg C ha?1 y?1, significantly higher than in ING (66 ± 13.4 kg C ha?1 y?1) and CON (109 ± 44.8 kg C ha?1 y?1). Analyses of 13C revealed a significant increase in newly produced SOC in both soil layers in ORG. However, the carbon conversion efficiency (CE: increased organic carbon in soil divided by organic carbon input) was lower in ORG (14.4%–21.7%) than in ING (18.2%–27.4%). Among the four particle‐sizes in the 0–20 cm layer, the silt fraction exhibited the largest proportion of increase in SOC content (57.8% and 55.4% of the SOC increase in ORG and ING, respectively). A similar trend was detected in the 20–40 cm soil layer. Over all, intensive organic (ORG) vegetable production increases soil organic carbon but with a lower carbon conversion efficiency than integrated (ING) management.  相似文献   
9.
AIM:To study the effect of C/EBP homologous protein (CHOP) on the apoptosis of renal tubular epithelial HK2 cells. METHODS:The serum mRNA levels of CHOP in the patients with acute kidney injury and healthy controls were detected by qPCR. In vitro, renal tubular epithelial HK2 cells were divided into control group, negative group (transfected with negative control siRNA), si-CHOP group (transfected with CHOP siRNA), and induced by transforming growth factor-β1 (TGF-β1). The viability of the cells was measured by MTT assay, and the apoptotic rate was analyzed by flow cytometry. The protein levels of nuclear antigen Ki-67, proliferating cell nuclear antigen (PCNA), caspase-3 and cleaved caspase-3 were determined by Western blot. RESULTS:Compared with the healthy controls, the serum mRNA levels of CHOP in the patients with acute kidney injury were increased significantly (P<0.05). Transfection with CHOP siRNA significantly decreased the expression of CHOP in the renal tubular epithelial HK2 cells (P<0.05). Knock-down of CHOP expression by siRNA significantly increased the viability of renal tubular epithelial HK2 cells (P<0.05), decreased the apoptotic rate (P<0.05), increased the expression of Ki-67 and PCNA (P<0.05), and down-regulated the protein level of cleaved caspase-3 (P<0.05). CONCLUSION:The serum mRNA levels of CHOP were increased in the patients with acute kidney injury. Knock-down of CHOP expression inhibits the apoptosis of renal tubular epithelial cells by regulating the expression of proliferation-and apoptosis-related proteins.  相似文献   
10.
Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains unclear.In this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,2016.Results showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 a.Soil organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total variation.Particularly,soil C:N ratio was significantly and positively related with the Shannon-Wiener index.This study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them.  相似文献   
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