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1. chinaXiv:202104.00021 [pdf]

“One-to-three” droplet generation-based digital microfluidics for parallel immunoassay.docx

Kai, Jin; Chenxuan, Hu; Siyi, Hu; Jinhua, Li; Hanbin, Ma
Subjects: Biology >> Bioengineering

In digital microfluidics, droplet generation is the fun, as the basis for a series of droplet manipulations including mixing, separation, dispensing, etc., has always been the focus in the field of digital microfluidics. Currently, the performance of DMF-based droplet splitting is highly influenced by the ratio of electrode size and the gap between the upper and lower plates. Here we propose a "one to three" droplet splitting method. In "one to three" spitting method, a pair of opposite electrowetting forces are applied to the droplet. As the electrowetting force is applied on the splitting position, a middle child droplet and two mother liquid droplets generate. The aspect ratio of child droplet is close to 1:2. "One to three" spitting method is then applied to magnetic beads immunoassay. Magnetic beads are retained in child droplets under small magnetic force with high magnetic bead washing efficiency. Simultaneous detection of five B-type natriuretic peptide analyte samples are performed on a single chip within 10 minutes. Correlation coefficient (R2) of the calibration curve was 0.9942, and the detection limit was less than 5pg/mL. This unique method of digital microfluidic droplet splitting has great potential in other application fields.

submitted time 2021-04-07 Hits66Downloads28 Comment 0

2. chinaXiv:202104.00005 [pdf]

Taxonomic revision of the holotype of Proboselaphus watasei Matsumoto, 1915 (Bovidae, Artiodactyla) from Chuanyu area, China

NISHIOKA Yuichiro; KOHNO Naoki; KUDO Yuichiro
Subjects: Biology >> Zoology

A taxonomic revision of Proboselaphus watasei Matsumoto, 1915 (Bovidae, Artiodactyla) from the Pleistocene of Chuanyu area, China demonstrates that this genus and species names are invalid. The holotype with a skull and mandibles was recently rediscovered in the fossil collection by Nobuo Naora, which is housed in the National Museum of Japanese History, Chiba Prefecture, Japan. Proboselaphus watasei was described as a closely-related species to living nilgai, or Boselaphus tragocamelus, in South Asia, based on general characteristics of pecorans, such as small bony horn-cores and hypsodont cheek teeth. However, the cranial and dental morphologies re-examined in the present study clearly show that the holotype has cervid-specific characteristics: e.g., the fronto-parietal surface curving dorsally, the basioccipital with a triangular outline, and molars with isolated anterior and posterior lobes. The molars of the holotype are comparable to those of Cervus unicolor, in having strong accessary structures (or spurs, cingulums/cingulids, and styles/stylids), and are as large as those of Cervus cf. C. unicolor from the Pleistocene deposits in southern China. This taxonomic change suggests that any crown-boselaphins had not dispersed into East Asia since the Pleistocene.

submitted time 2021-04-02 From cooperative journals:《古脊椎动物学报》 Hits110Downloads48 Comment 0

3. chinaXiv:202104.00006 [pdf]

Climate change and evolution of early lagomorphs (Mammalia): a study perspective based on new materials of Ordolagus from Nei Mongol (northern China)

Subjects: Biology >> Zoology

The Early Oligocene is a critical time for global climate changes in the Cenozoic. This epoch witnessed severe mammalian faunal turnovers known as “Grande Coupure” in Europe and “Mongolian Remodelling” in Asia. However, insights about morphological changes in Oligocene mammal lineages have not been explored in detail. One of the least diversified groups of recent mammals, lagomorpha, is globally common in the fossil records, especially in Asia. During the Oligocene, many Eocene archaic lagomorph taxa died out and were replaced by more advanced forms. New findings from Nei Mongol and re-examination of the specimens from older collections enabled a revision of a common Asian lagomorph genus, Ordolagus, which possibly has a close affinity with the Middle–Late Eocene genus Gobiolagus. In Nei Mongol, we recognized the presence of Ordolagus during the basal Early Oligocene. Comparisons with coeval and slightly older lagomorph taxa from Asia and North America show that Ordolagus attained some salient tooth morphological characters (i.e., development of anteroconid on p3, full hypselodonty of cheek teeth, and lingual connection of trigonid and talonid on p4–m2), which are also the key features of modern leporids. The appearance of those morphologic features in Ordolagus is coeval to major global or regional climatic changes. Further investigations on Asian early lagomorphs compared with the study of other small mammals and local climatic factors will be essential to refine the role of lagomorphs as palaeoclimatic proxies.

submitted time 2021-04-02 From cooperative journals:《古脊椎动物学报》 Hits110Downloads47 Comment 0

4. chinaXiv:202104.00007 [pdf]

An Upper Miocene “Hipparion fauna” locality sandwiched by basalts in Hanjiaying, Nei Mongol

Subjects: Biology >> Zoology

Here we report a Hipparion fauna locality discovered in between two basalt layers near Hanjiaying Village, Jining District, Wulanchabu City, Nei Mongol. K-Ar isotopic dating of the lower and upper level of the basalt constrains the age of the fauna from 7.2 to 6.8 Ma. Compared with classical Hipparion fauna from northern China, the Hanjiaying fauna is closer to those from Baode of Shanxi, Siziwang Banner of Nei Mongol and the Linxia Basin of Gansu. It is similar to the Loc. 43, 44 and 49 from Baode by faunal composition, confirming their age to be ~7.0 Ma rather than 5.5 Ma. The high similarity with the fossils from Wulanhua, Siziwang Banner, Nei Mongol, verified the age of Wulanhua fauna at about 7 Ma. Compared with faunas from the Linxia Basin, Gansu, it is more similar to those from the upper part of the Liushu Formation, especially the Yangjiashan fauna. Based on the faunal composition and their tooth morphology, the Hanjiaying fauna could be included in the “Gazella dorcadoides” fauna, which is supposed to be at the west paleobiome in northern China during the Late Miocene.

submitted time 2021-04-02 From cooperative journals:《古脊椎动物学报》 Hits68Downloads26 Comment 0

5. chinaXiv:202104.00008 [pdf]


林红玲; 梁士楚; 姚义鹏; 姜勇; 包含; 农彩汪; 宋静; 黄佳; 甘鑫梅
Subjects: Biology >> Botany >> Applied botany

落叶阔叶林是亚热带岩溶石山典型的森林植被类型之一,为了了解此类森林植被的群落类型和组成结构,本研究在桂林阳朔县和灵川县岩溶生境典型的落叶阔叶林内设置了 49 个 20 m× 20 m 的随机样方,在野外调查的基础上进行群落数量分类和排序,对其群落类型进行划分。在此基础上对不同类型的群落种类组成、结构及其分布与环境因子的耦合关系进行深入分析。结果表明:(1)桂林岩溶石山落叶阔叶林可划分 3 个群丛组类型,即群丛组 A:南酸枣-喜树+巴豆群丛组(ASS. Choerospondias axillaris-Camptotheca acuminata+Croton tiglium),群丛组 B:光皮梾木-喜树群丛组(ASS. Swida wilsoniana-Camptotheca acuminata),群丛组 C:麻栎-檵木群丛组(ASS. Quercus acutissima-Loropetalum chinense)。(2)不同群落类型中常绿和落叶物种的丰富度、多度、胸高断面积及重要值的变化:在乔木层中,3 个群丛组均为落叶物种占优势;在灌木层中,群丛组 A、B 以落叶物种占优势,群丛组 C 以常绿物种占优势。(3)在 1~5 cm 和5~10 cm 径级内,群丛组 A 和 B 的落叶物种在 4 个度量指标上均大于常绿物种,群丛组 C 除了物种丰富度以外,均为常绿物种大于落叶物种;在 ≥10 cm 径级中,除了群丛组 B 的物种丰富度外,3 个群丛组中的各项指标均为落叶物种占主导地位。(4)岩石裸露率、海拔、坡向、土壤含水量、土壤 pH、土壤有机质、全氮、速效氮、速效钾、林冠开阔度和人为干扰是影响研究区不同类型群落分布的主要环境因子。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits90Downloads53 Comment 0

6. chinaXiv:202104.00009 [pdf]


王琦; 严靖
Subjects: Biology >> Botany >> Applied botany

在进行多肉植物资源调查时,在我国山东发现一仙人掌科仙人掌属新记录种——匍地仙人掌[Opuntia humifusa (Raf.) Raf.]。该种具有独特的匍匐生长习性,叶状茎深绿色,无白霜,无针状刺,花黄色,与国内分布的仙人掌属其他物种区别明显。匍地仙人掌原产于北美洲,是仙人掌科为数不多的耐寒种类之一,现归化于中国山东省日照市五莲县,系目前发现的在我国野外分布最北的仙人掌科植物。该种可能于? 20 世纪? 50 年代在国家推广中药材时期引入种植,人类活动致使其种群逐渐扩散。同时,对匍地仙人掌与江苏报道的二色仙人掌之间的分类学问题进行了论述,并对将来匍地仙人掌在我国暖温带地区合理的开发利用进行了展望。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits70Downloads31 Comment 0

7. chinaXiv:202104.00010 [pdf]


秦佳双; 顾大形; 倪隆康; 何文; 阮杨春; 黄玉清; 王权
Subjects: Biology >> Botany >> Applied botany

叶片水分状况是反映植被生理状况的重要指标,构建高普适性的植物叶片含水率高光谱反演模型对准确评价岩溶和非岩溶植被生态功能具有重要意义。以我国西南典型区域内岩溶区与非岩溶区共 17 种植物 694 个样品为研究对象,同步测量叶片含水率和反射光谱,采用单波段、差值型、比值型、归一化型等四类光谱指数模型,对反射光谱及一阶导数光谱进行全波段搜索分析。结果表明:光谱指数 D 2048 -D 1733 的建模与验证结果均最好,为岩溶植物叶 片 含 水 率 的 最 佳 估 计 光 谱 指 数 ; 对 于 非 岩 溶 植 物 , 光 谱 指 数 D 2356 /D 1885 和(D 2356 -D 1885 )/(D 2356 +D 1885 )建模与验证结果均相差很小,均可作为叶片含水率最佳估计模型;该研究结果还表明叶片绒毛对岩溶植物叶片含水率反演光谱指数构建影响不大。总体上,新构建的最优光谱指数对岩溶区与非岩溶区植物叶片含水率的拟合效果优于传统指数,具有较好的普适性,可为精准评估桂北地区植被水分状态提供科学依据。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits55Downloads25 Comment 0

8. chinaXiv:202104.00011 [pdf]


张玉仙; 唐 辉; 黄夕洋; 刘宝玉; 李文兰
Subjects: Biology >> Botany >> Applied botany

为探索黄花倒水莲春梢生理生化特性的差异以及不同内源激素的变化规律,该文对黄花倒水莲春梢的生长动态进行监测,采用间接酶联免疫吸附法(ELISA)测定脱落酸(ABA)、生长素(IAA)、赤霉素(GA)、乙烯(ETH)和玉米素核苷(ZR)五种内源激素含量的动态变化,并对两者间的相关性进行分析。结果表明:黄花倒水莲春梢生长发育过程可分为快速增长期(0~12 d)、生长转折期(16~20 d)和缓慢增长期(24~32 d)三个阶段。内源激素 ABA、GA、ETH 和 ZR 含量在缓慢增长期显著高于快速增长期和生长转折期,IAA 含量各时期差异较小。相关性研究结果发现,春梢长、底部叶长和叶宽在快速增长期与 ABA、GA、ETH 和 ZR 含量呈负相关,且与 ZR 含量具有一定显著性,与 IAA 含量呈正相关;生长转折期,各指标与 GA、ETH 和 ZR 含量呈正相关,与 GA 含量具有一定显著性,与 ABA 含量呈负相关;缓慢增长期,各指标与五种内源激素含量均呈正相关,与IAA 和 ZR 含量具有一定显著性。该研究结果为生产上利用外源激素调控黄花倒水莲春梢抽出以及生长提供了理论基础。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits49Downloads22 Comment 0

9. chinaXiv:202104.00012 [pdf]


蒋向辉; 肖龙骞; 杨永平
Subjects: Biology >> Botany >> Applied botany

黄褐毛忍冬具有消炎、抗菌、免疫调节等多种功效,但容易与忍冬属其他物种混淆,通过生药学研究将为黄褐毛忍冬的鉴定工作和药材标准的制定提供科学依据。该文采用植物学鉴定、显微镜观察、薄层色谱鉴定和分子鉴定的方法从植物学性状、药材显微特征、薄层色谱和 ITS(internal transcribed spacer)序列特征等方面对黄褐毛忍冬进行了专属性特征鉴定。结果表明:(1)黄褐毛忍冬花朵横切面分泌细胞较多,花瓣外表面有黄褐色腺毛;花冠表皮上层细胞为多角形,蚌形花粉囊对开,花粉粒形状规则,有三角形和卵圆形两种,油室椭圆形。(2)粉末显微检测发现中柱鞘纤维呈短棱形;木栓细胞棱角明显,呈浅黄色;木纤维呈粗短的棱形,偶见有弯曲;网纹导管较多,细胞腔密布草酸钙方晶。(3)薄层色谱显示黄褐毛忍冬花中三柰酚含量较高,三柰酚可作为黄褐毛忍冬的检视成分。(4)基于 ITS 序列系统聚类结果显示,ITS 序列可以作为 DNA 条形码将黄褐毛忍冬、灰毡毛忍冬、华南忍冬和金银花准确地区分。上述结果表明黄褐毛忍冬生药学特征明显,本研究为黄褐毛忍冬药材鉴定、成分分析和质量标准制定提供了参考。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits53Downloads31 Comment 0

10. chinaXiv:202104.00013 [pdf]

葡萄 CBF4 生物信息学及对低温和硅酸钾响应分析

张红梅; 王旺田; 张芮; 杨科; 王宝强; 王翠玲
Subjects: Biology >> Botany >> Applied botany

为探究葡萄 CBF4 基因的结构和表达特征,该研究以葡萄为材料,对葡萄 CBF4 基因进行生物信息学及低温和硅酸钾响应分析。结果表明:CBF4 蛋白定位在细胞核,有 5 个磷酸化位点和 14个糖基化位点,无信号肽,是一个亲水的、脂溶性较差的膜外蛋白。二级结构以无规则卷曲为主,比例为 56.88%。该蛋白包含一个 AP2/EREBP 结构域。CBF4 蛋白的多序列和系统进化分析表明酿酒葡萄与美洲葡萄的同源性最高、亲缘关系最近。荧光定量 PCR 分析显示,低温胁迫后 CBF4 基因在葡萄叶片中表达水平上调,说明 CBF4 基因可能参与了葡萄叶片低温胁迫的响应。低温条件下,施加硅酸钾 CBF4 基因表达具有差异性,说明该基因在不同的葡萄组织中对硅酸钾的响应机制可能不同。以上结果为进一步研究葡萄 CBF4 基因的功能和机理奠定了基础。

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