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941.
Prussian blue analogs with an open framework are ideal cathodes for Na‐ion batteries. A superior high‐rate and highly stable monoclinic nickel hexacyanoferrate (NiHCF‐3) is synthesized via a facile one‐step crystallization‐controlled co‐precipitation method. It gives a high specific capacity of 85.7 mAh g?1, nearly to its theoretical value. It also exhibits an excellent rate capability with a high capacity retention ratio of 78% at 50 C and a stable cycling performance over 1200 cycles. Through the ex situ X‐ray diffraction and pair distribution function measurements, it is found that the monoclinic structure with distorted framework is greatly related to the high Na content. The electronic structure studies by density functional theory (DFT) calculation demonstrate that NiHCF‐3 deformation promotes the framework conductivity and improves the electrochemical activity of Fe, which results in an ultrahigh‐rate performance of monoclinic phase. Furthermore, the high‐quality monoclinic (NiHCF‐3) exhibits excellent compatibility with both hard carbon and NaTi2(PO4)3 anodes in full cells, which shows great prospects for the application in the large‐scale energy storage systems.  相似文献   
942.
著: 《生物信息学》2019,26(9):119-131
水文系统是区域景观系统的主要组成部分—包括河流、湖泊、海洋以及人工运河。全球大多数城市都临水而建。水对人类健康和幸福感构成了诸多威胁,但也带来了许多(常常只是潜在的)益处。随着城市的扩张和人口的日益密集,优秀的城市规划设计可以创造或改善滨水空间利用,这可能成为改善人类健康和幸福感的宝贵途径。随着工业和港口设施的搬迁,置换出了滨水蓝色空间,对蓝色空间水资源的优化管理能有效减少城市水污染。洪水风险可能会因洪泛区的城市扩张而加剧,因此在汇水区整体层面统一协调水资源管理至关重要。基于已被证实蓝色和绿色空间对健康和幸福感的诸多益处,规划者和设计师应该充分利用蓝绿空间来创造更好的空间。虽然已有许多项目将滨水空间改造成供人使用的娱乐休闲空间,但对它们在健康和幸福感方面的成功因素进行系统评价的很少。“蓝色健康研究项目”(The BlueHealth Research Project)的重点是通过更完善的实例研究,探究如何规划和设计城市蓝色空间来改善大众健康和幸福感。将蓝色空间作为一个新兴的城市景观研究领域进行介绍,并系统梳理了全球蓝色再生项目的一些初步发现,同时总结这些项目成功的关键。  相似文献   
943.
陈梦姣  解廷娜  陈春 《菌物学报》2019,38(3):372-380
光在调控真菌的多种生理过程中发挥着重要作用。为探究光照对新蚜虫疠霉Pandora neoaphidis产孢的影响,本文研究了不同波长光源(蓝光、绿光、白光、红光、黄光)和无光黑暗条件对新蚜虫疠霉分生孢子弹射能力的影响,通过cDNA末端的快速扩增(RACE)对新蚜虫疠霉的蓝光受体蛋白基因pnwc-1进行克隆并对其进行生物信息学分析,利用qRT-PCR对蓝光光源不同照射时长下pnwc-1的表达量进行了定量分析。结果表明,蓝色光源(波长460–465nm)照射后的新蚜虫疠霉菌丝产生的分生孢子数量显著高于其他波长光源,排序为:蓝光>绿光>白光>红光>黄光>无光。另外,分析克隆获得的全长为2 423bp的pnwc-1基因发现,其编码的蛋白具有蓝光受体蛋白典型的保守结构域,同源比对结果显示新蚜虫疠霉与接合菌门真菌归为一类但相对独立。qRT-PCR的定量分析结果表明随着照射时长增加,蓝光处理能显著提高pnwc-1的表达量,而且pnwc-1的相对表达量与累积产孢量存在正相关(R2=0.9798)。本研究为后续蓝光及其受体基因功能的深入研究提供了实验基础,并促进以新蚜虫疠霉为代表的虫霉目真菌在害虫生物防治中的应用。  相似文献   
944.
We assessed scarring patterns as evidence of fisheries interactions for three populations of false killer whales in Hawai‘i. Bycatch of the pelagic population in the tuna longline fishery exceeds their Potential Biological Removal level. Scarring was assessed by seven evaluators as consistent, possibly consistent, or not consistent with fisheries interactions, and average scores computed. Scores were highest for scarred main Hawaiian Island (MHI) false killer whales, followed by pelagic and Northwestern Hawaiian Island (NWHI) individuals. Considering only whales for which the majority of evaluators scored scarring as consistent revealed significant differences among populations in the percentage of individuals scarred; MHI: 7.5%, pelagic: 0%, NWHI: 0%. Assessment by social cluster for the MHI population showed that 4.2% of Cluster 1, 7.1% of Cluster 2, and 12.8% of Cluster 3 individuals had such scarring, although differences between clusters were not statistically significant. There was a significant sex bias; all sexed individuals (n = 7) with injuries consistent with fisheries interactions were female. The higher proportion of MHI individuals with fisheries‐related scarring suggests that fisheries interactions are occurring at a higher rate in this population. The bias towards females suggests that fisheries‐related mortality has a disproportionate impact on population dynamics.  相似文献   
945.
Reports of killer whales (Orcinus orca) preying on large whales have been relatively rare, and the ecological significance of these attacks is controversial. Here we report on numerous observations of killer whales preying on neonate humpback whales (Megaptera novaeangliae) off Western Australia (WA) based on reports we compiled and our own observations. Attacking killer whales included at least 19 individuals from three stable social groupings in a highly connected local population; 22 separate attacks with known outcomes resulted in at least 14 (64%) kills of humpback calves. We satellite‐tagged an adult female killer whale and followed her group on the water for 20.3 h over six separate days. During that time, they attacked eight humpback calves, and from the seven known outcomes, at least three calves (43%) were killed. Overall, our observations suggest that humpback calves are a predictable, plentiful, and readily taken prey source for killer whales and scavenging sharks off WA for at least 5 mo/yr. Humpback “escorts” vigorously assisted mothers in protecting their calves from attacking killer whales (and a white shark, Carcharodon carcharias). This expands the purported role of escorts in humpback whale social interactions, although it is not clear how this behavior is adaptive for the escorts.  相似文献   
946.
目的:探讨吲哚菁绿(indocyanine green,ICG)联合亚甲蓝在乳腺癌前哨淋巴结活检(sentinel lymph node biopsy,SLNB)中的临床应用价值。方法:共入组39例乳腺癌患者,在光学分子影像手术导航系统(surgical navigation system,SNS)的引导下,使用ICG联合亚甲蓝实施SLNB。快速冰冻病理证实前哨淋巴结(sentinel lymph node,SLN)转移者,即刻行腋窝淋巴结清扫(axillary lymph node dissection,ALND);SLN阴性者免于ALND。结果:联合法实施SLNB检出率95%,成功检出SLN125个,平均检出3.2个SLN,准确率95.0%,灵敏度100%,假阴性率0%;蓝染法检出率87.2%,成功检出SLN71个,平均检出1.8个SLN,准确率89.7%,灵敏度93.7%,假阴性率为6.3%;统计结果采用x2检验,检验结果具有统计学意义。结论:ICG联合亚甲蓝实施乳腺癌SLNB成功率高,假阴性率低,临床效果不亚于亚甲蓝,是实施SLNB的新方法。  相似文献   
947.
为明确黑胸散白蚁Reticulitermes chinensis在绿地取食群体大小与活动范围,选取白蚁活动频繁、数量较多的5个诱集点进行研究。试验采用三重标记重捕法,染色标记物为0.2%耐尔兰滤纸(wt/wt)。经统计和测量发现,诱集点A、B、C和D处的取食个体数量分别为78.8、11.3、21.4和8.3万头,距诱集箱的最大取食直线距离分别为11.8 m(A)、5.5 m(B)和2.3 m(D)。由于C点的3次重捕均在诱集箱处完成,因此未能获得该白蚁群体的活动范围数据。而在诱集点E处,2次释放(诱集箱和7号饵站)均未能在释放点和周围饵站内重捕到标记白蚁。黑胸散白蚁4个群体的取食群体数量为8-79万头,连续监测30 d,其距诱集箱的取食直线距离为0-12 m,而实际群体数量和活动范围均大于试验中所得的数据。  相似文献   
948.
目的探讨大分子葡萄糖酐血瘀模型小鼠偶氮蓝渗出量和血瘀程度的相关性。方法用0.5%偶氮蓝将大分子葡萄糖酐配制成10%、5%、2.5%的浓度,尾静脉注射,0.1mL/10g,分别在注入后0.5、1、2h对造模小鼠耳、舌的颜色进行观察,并用丙酮无水硫酸钠溶液将耳组织中的偶氮蓝提出,在590μm测定各实验组小鼠耳廓偶氮蓝含量。结果实验结果表明,不同浓度的大分子葡萄糖酐所致血瘀模型的血瘀程度明显不同,同单用偶氮蓝组小鼠相比,大分子葡萄糖酐10%、5%、2.5%的浓度造模小鼠的耳、舌的颜色明显呈现蓝色,随着剂量的增加偶氮蓝渗出量明显增加(P<0.05或0.01),在尾静脉注射后0.5h,造模小鼠耳、舌的颜色呈现点状或片状蓝色,在尾静脉注射后1h,造模小鼠耳、舌的颜色明显呈现蓝色,在尾静脉注射后2h,造模小鼠耳、舌的颜色明显消退。结论表明大分子葡萄糖酐所致血瘀模型的血瘀程度和偶氮蓝渗出量明显相关,呈现明显的量效和时效关系。  相似文献   
949.
Histological staining methods commonly used for detecting cellulose and lignin in cell walls were combined with epifluorescence microscopy to visualize differences in lignification between and within cellular elements. We tested our approach on sections of one-year-old branches of Fraxinus ornus L., Myrtus communis L., Olea europaea L., Pistacia lentiscus L. and Rhamnus alaternus L., containing both normal and tension wood. Sections were subjected to various staining techniques, viz. safranin O, safranin O/fast green FCF, and alcoholic solutions of safranin O/astra blue, according to the commonly accepted protocols. Stained and unstained sections were compared using both light and epifluorescence microscopy. Safranin O with or without counterstaining hid the strong fluorescence of vessel walls, cell corners and middle lamellae allowing the secondary wall fibers to fluoresce more clearly. Epifluorescence microscopy applied to stained sections showed more cell wall details than autofluorescence of unstained sections or white light microscopy of counterstained sections. This simple approach proved reliable and valuable for detecting differences in lignification in thick sections without the need for costly equipment.  相似文献   
950.
Xian Y  Hu Y  Liu F  Xian Y  Feng L  Jin L 《Biosensors & bioelectronics》2007,22(12):2827-2833
In this paper, we propose a strategy to form nanoelectrode arrays by electrochemical deposition of the Prussian blue (PB) through highly ordered porous anodic alumina (PAA) membrane. The structure and morphology of the nanoarrays were characterized by scanning electron microscopy (SEM). As the highly ordered PB arrays can behave as an ensemble of closely spaced but isolated nanoelectrodes, the nanostructured PB arrays are successfully applied to improve the analytical performances of glucose by electrocatalytic reduction enzymatically liberated H2O2. The resulting PB based nanoelectrode arrays show a wide linear calibration range over three orders of magnitude of glucose concentrations (5.0 × 10−6 to 8.0 × 10−3 M) and a low detection limit of 1 μM. Moreover, the biosensor exhibits other good characteristics, such as short response time, high selectivity, excellent operation stability. In addition, effects of the glucose oxidase (GOx) loading, applied potential and pH on the biosensor performance were also discussed.  相似文献   
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