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991.
Wheat is a major crop worldwide, mainly cultivated for human consumption and animal feed. Grain quality is paramount in determining its value and downstream use. While we know that climate change threatens global crop yields, a better understanding of impacts on wheat end-use quality is also critical. Combining quantitative genetics with climate model outputs, we investigated UK-wide trends in genotypic adaptation for wheat quality traits. In our approach, we augmented genomic prediction models with environmental characterisation of field trials to predict trait values and climate effects in historical field trial data between 2001 and 2020. Addition of environmental covariates, such as temperature and rainfall, successfully enabled prediction of genotype by environment interactions (G × E), and increased prediction accuracy of most traits for new genotypes in new year cross validation. We then extended predictions from these models to much larger numbers of simulated environments using climate scenarios projected under Representative Concentration Pathways 8.5 for 2050–2069. We found geographically varying climate change impacts on wheat quality due to contrasting associations between specific weather covariables and quality traits across the UK. Notably, negative impacts on quality traits were predicted in the East of the UK due to increased summer temperatures while the climate in the North and South-west may become more favourable with increased summer temperatures. Furthermore, by projecting 167,040 simulated future genotype–environment combinations, we found only limited potential for breeding to exploit predictable G × E to mitigate year-to-year environmental variability for most traits except Hagberg falling number. This suggests low adaptability of current UK wheat germplasm across future UK climates. More generally, approaches demonstrated here will be critical to enable adaptation of global crops to near-term climate change.  相似文献   
992.
993.
To improve the utilization efficiency of precious metals, metal‐supported materials provide a direction for fabricating highly active and stable heterogeneous catalysts. Herein, carbon cloth (CC)‐supported Earth‐abundant CoS2 nanosheet arrays (CoS2/CC) are presented as ideal substrates for ultrafine Pt deposition (Pt‐CoS2/CC) to achieve remarkable performance toward the hydrogen and oxygen evolution reactions (HER/OER) in alkaline solutions. Notably, the Pt‐CoS2/CC hybrid delivers an overpotential of 24 mV at 10 mA cm?2 and a mass activity of 3.89 A Ptmg?1, which is 4.7 times higher than that of commercial Pt/C, at an overpotential of 130 mV for catalyzing the HER. An alkali‐electrolyzer using Pt‐CoS2/CC as a bifunctional electrode enables a water‐splitting current density of 10 mA cm?2 at a low voltage of 1.55 V and can sustain for more than 20 h, which is superior to that of the state‐of‐the‐art Pt/C+RuO2 catalyst. Further experimental and theoretical simulation studies demonstrate that strong electronic interaction between Pt and CoS2 synergistically optimize hydrogen adsorption/desorption behaviors and facilitate the in situ generation of OER active species, enhancing the overall water‐splitting performance. This work highlights the regulation of interfacial and electronic synergy in pursuit of highly efficient and durable supported catalysts for hydrogen and oxygen electrocatalytic applications.  相似文献   
994.
Abstract The neural gland complex of Ascidia interrupta consists of three parts: dorsal tubercle, ciliated duct, and neural gland. The dorsal tubercle protrudes above the pharyngeal lining and bears a ciliated funnel. The funnel opens into a ciliated duct which opens into the neural gland, a blind sac in a blood sinus below the brain. Funnel and duct cells are joined by adhaerens junctions and, apically, by putative tight junctions. The neural gland wall is a loose, irregular, non-ciliated epithelium of phagocytes. Adhaerens, but not tight, junctions join the cells. Secretory cells were not observed. Tracers delivered onto the dorsal tubercle and dissolved in seawater around undissected animals are transported unidirectionally inward into the neural gland. The continuous ciliary incurrent moves the tracers across the wall of the neural gland and into the pharyngeal blood vessels. Small particulates and large macromolecules, however, are removed from the water stream by endocytosis on neural gland cells. Large particulates delivered onto the dorsal tubercle do not enter the system but rather are rejected by cilia on the surface of the tubercle. The neural gland complex is interpreted as an organ of blood volume regulation that consists of a pump (cilia) and coarse (tubercle) and fine (gland) filters. Analogous and homologous systems are discussed.  相似文献   
995.
灰蓝姬鹟的孵卵节律   总被引:2,自引:0,他引:2  
贾陈喜  王众  孙悦华 《四川动物》2003,22(4):238-240,F004
2 0 0 2年在莲花山自然保护区使用温度自动记录装置对灰蓝姬的孵卵节律进行了研究。研究表明 ,灰蓝姬雌鸟日平均离巢 31.2 5± 7.5 0次 (n =8天 ) ,平均每次离巢持续时间为 7± 2min (n =2 6 4 ) ,平均在巢持续时间 2 1± 9min (n =2 5 6 )。雌鸟在巢率与环境温度间存在显著的负相关关系 (Spearman相关 ,r =- 0 .30 4 ,P <0 .0 1)。进一步的分析表明 ,灰蓝姬雌鸟每次离巢持续时间与环境温度呈显著的正相关 (Spearman相关 ,r =0 .2 6 1,P <0 .0 1) ,每次在巢时间和离巢次数均与环境温度无关 (在巢时间 ,r =0 .0 2 6 ,P =0 .6 82 ;离巢次数 ,r =0 .0 14 ,P =0 .879)。认为灰蓝姬雌鸟主要通过调节离巢时间的长短来控制孵卵节律  相似文献   
996.
Two series of novel naphthalin-containing pyrazoline derivatives C1C14 and D1–D14 have been synthesized and evaluated for their EGFR/HER-2 inhibitory and anti-proliferation activities. Compound D14 displayed the most potent activity against EGFR and A549 cell line (IC50 = 0.05 μM and GI50 = 0.11 μM), being comparable with the positive control Erlotinib (IC50 = 0.03 μM and GI50 = 0.03 μM) and more potent than our previous compounds C0–A (IC50 = 5.31 μM and GI50 = 33.47 μM) and C0–B (IC50 = 0.09 μM and GI50 = 0.34 μM). Meanwhile, compound C14 displayed the most potent activity against HER-2 and MCF-7 cell line (IC50 = 0.88 μM and GI50 = 0.35 μM), being a little less potent than Erlotinib (IC50 = 0.16 μM and GI50 = 0.08 μM) but far more potent than C0–A (IC50 = 6.58 μM and GI50 = 27.62 μM) and C0–B (IC50 = 2.77 μM and GI50 = 3.79 μM). The docking simulation was performed to analyze the probable binding models and the QSAR models were built for reasonable design of EGFR/HER-2 inhibitors at present and in future. The structural modification of introducing naphthalin moiety reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity. Moreover, the replacement of thiourea skeleton by using benzene ring resulted in the slight diversity of the two series towards specific targets.  相似文献   
997.
998.
Background aimsWe recently showed that co-transplantation of mesenchymal stromal cells (MSCs) improves islet function and revascularization in vivo. Pre-transplant islet culture is associated with the loss of islet cells. MSCs may enhance islet cell survival or function by direct cell contact mechanisms and soluble mediators. We investigated the capacity of MSCs to improve islet cell survival or β-cell function in vitro using direct and indirect contact islet-MSC configurations. We also investigated whether pre-culturing islets with MSCs improves islet transplantation outcome.MethodsThe effect of pre-culturing islets with MSCs on islet function in vitro was investigated by measuring glucose-stimulated insulin secretion. The endothelial cell density of fresh islets and islets cultured with or without MSCs was determined by immunohistochemistry. The efficacy of transplanted islets was tested in vivo using a syngeneic streptozotocin-diabetic minimal islet mass model. Graft function was investigated by monitoring blood glucose concentrations.ResultsIndirect islet-MSC co-culture configurations did not improve islet function in vitro. Pre-culturing islets using a direct contact MSC monolayer configuration improved glucose-stimulated insulin secretion in vitro, which correlated with superior islet graft function in vivo. MSC pre-culture had no effect on islet endothelial cell number in vitro or in vivo.ConclusionsPre-culturing islets with MSCs using a direct contact configuration maintains functional β-cell mass in vitro and the capacity of cultured islets to reverse hyperglycemia in diabetic mice.  相似文献   
999.
1000.
Journal of Mammalian Evolution - Mammalian dental formulae often are highly conserved, at least at a generic level. In walruses (Odobenus rosmarus), the constraints of dentition in light of...  相似文献   
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