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1. chinaXiv:201906.00025 [pdf]

The tetrapod fauna of the upper Permian Naobaogou Formation of China— 4. the diversity of dicynodonts

LIU Jun
Subjects: Biology >> Zoology

The Permian dicynodont records were previously rare in North China, but many dicynodont specimens have been collected from the Naobaogou Formation in Daqingshan area, Nei Mongol since 2009. Among these specimens, seven morphotypes have been identified, and they may represent seven different species: two of them are closely related to Daqingshanodon limbus, three or four are closely related to Jimusaria sinkianensis, and one may be closely related to Turfanodon. This study shows the dicynodonts also have a high diversity at the species level in North China.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits8Downloads2 Comment 0

2. chinaXiv:201906.00026 [pdf]

Molecular clock dating using MrBayes

ZHANG Chi
Subjects: Biology >> Zoology

This paper provides an overview and a protocol of molecular clock dating using MrBayes. Two modern approaches, total-evidence dating and node dating, are demonstrated using a truncated dataset of Hymenoptera with molecular sequences and morphological characters. The similarity and difference of the two methods are compared and discussed. Besides, a non-clock analysis is performed on the same dataset to compare with the molecular clock dating analyses.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits10Downloads3 Comment 0

3. chinaXiv:201906.00027 [pdf]

Metatarsal II osteohistology of Xixianykus zhangi (Theropoda: Alvarezsauria) and its implications for the development of the arctometatarsalian pes

QIN Zi-Chuan; ZHAO Qi; XU Xing
Subjects: Biology >> Zoology

The late-branching alvarezsaurian Xixianykus zhangi is among the smallest known non-avialan theropods. With great similarity to its close relatives, it is highly cursorial as indicated by proportionally long lower segments of the hindlimbs and the presence of an arctometatarsalian pes–a highly modified structure that has been suggested to improve cursorial capability in theropods. Here we describe the osteohistology of the metatarsal II of the holotype of X. zhangi (XMDFEC V 0011). Two rarely reported histological features, radial vascular canals and Sharpey’s fibers, are presented in this study. We suggest that both features are related to the development of the arctometatarsalian pes; however, further investigations of metatarsal osteohistology in theropods are required for the validation of our interpretation.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits9Downloads3 Comment 0

4. chinaXiv:201906.00028 [pdf]

Cladistic approach on chronological relationship of the Pleistocene mammalian faunas from China

DONG Wei; LIU Wen-Hui; BAI Wei-Peng
Subjects: Biology >> Zoology

There are many localities yielding the Pleistocene mammalian faunas in China. It offers excellent material for the study of mammalian evolution, biochronology,paleoecology,paleoenvironment, paleozoogeography, etc. Faunal assemblage characters and taxonomic extinction rates were widely used for determining the faunal ages in biochronology. Faunal binary similarity coefficients sequenced according to Brainerd-Robinson’s rule and antiquity coefficients were further developed methods in biochronology for dating the faunal ages. The faunal binary similarity coefficients are based on the presence or absence of a taxon in a fauna. It is similar to the presence or absence of a character of a species in cladistic analyses for phylogeny, and all faunas have a special ancestor-descendant relationship. The present work is an attempt to find the relationship of the faunas with cladistic methods by selecting three groups of faunas sequenced by faunal binary similarity coefficients according to Brainerd-Robinson’s rule and antiquity coefficients, to compare the results with different methods, and then to estimate the ages of the faunas not yet dated by physical or chemical methods. The estimations are as follow: Gulongshan in Dalian, Liaoning Province: 16–20 ka; Shanchengzi at Benxi, Liaoning Province: 20–30 ka; Hualongdong at Dongzhi Man site, Anhui Province: 150–400 ka; Xinghuashan at Nanzhao Man site, Henan Province: 150–400 ka; Donghe at Luonan Man site, Shaanxi Province: 500–700 ka; Bailongdong at Yunxi Man site, Hubei Province: 500–850 ka; Meipu at Yunxian, Hubei Province: 500–850 ka; Mohui at Tiandong Man site, Guangxi Autonomous Region: 1.2–1.8 Ma; Juyuandong at Liucheng, Guangxi Autonomous Region: 1.2–1.5 Ma; Chutoulang at Chifeng, Nei Mongol Autonomous Region: 1.6–1.9 Ma; Renzidong at Fanchang, Anhui Province: 1.9–2.4 Ma.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits12Downloads4 Comment 0

5. chinaXiv:201901.00103 [pdf]

Cranial osteology of Beipiaosaurus inexpectus (Theropoda: Therizinosauria)

LIAO Chun-Chi(1,2,3); XU Xing(1,2)
Subjects: Biology >> Zoology

Beipiaosaurus inexpectus, a key taxon for understanding the early evolution of therizinosaurians, has not been fully described since it was briefly reported on by Xu, Tang and Wang in 1999. Here we present a detailed description of the cranial anatomy of the holotype of this theropod dinosaur. B. inexpectus is unique in some of its cranial features such as the postorbital process of the frontal is large and its abrupt transition from the orbital rim, a long and sharp anterior process of the parietal, the elongate ventral ramus of the squamosal process of parietal, and external mandibular fenestra deep dorsoventrally and extremely posteriorly located. A number of plesiomorphic cranial features (such as relatively large dentary and less downturned degree of dentary symphysis) suggest that B. inexpectus is an early-branching Therizinosaurian, as proposed by previous studies. New information derived from our study is not only important for our understanding of the cranial anatomy of B. inexpectus but also significant to the study of the evolution of Therizinosauria.

submitted time 2019-01-16 From cooperative journals:《古脊椎动物学报》 Hits340Downloads5 Comment 0

6. chinaXiv:201812.00640 [pdf]

菊粉的生理功能及其在畜禽生产中的应用

陈佳亿(1); 陈凤鸣(1); 欧淑琦(1); 赵玉蓉(1)
Subjects: Biology >> Zoology

菊粉是一类植物源性的天然果聚糖,具有平衡肠道微生物、调节免疫和脂质代谢以及促进矿物质吸收等作用。作为一种天然的饲料添加剂,菊粉有改善畜禽肠道健康、提高免疫力等功效,具有良好的应用前景。本文综述了菊粉的理化性质、提取工艺、主要生理功能及其在畜禽生产中的应用状况,以期为菊粉在畜禽饲料中的应用提供参考。

submitted time 2018-12-25 From cooperative journals:《动物营养学报》 Hits1361Downloads307 Comment 0

7. chinaXiv:201812.00647 [pdf]

条纹锯鮨(Centropristis striata)幼鱼维生素C需要量

赵亭亭; 陈超; 邵彦翔; 张清雯; 刘玲
Subjects: Biology >> Zoology

本试验旨在研究条纹锯鮨(Centropristis striata)幼鱼维生素C需要量。试验采用单因素试验设计法,选取平均体重为(88.34±24.1) g的条纹锯鮨幼鱼630尾,随机分为7组,每组3个重复,每个重复30尾鱼。各组分别投喂维生素C含量(实测值)分别为10.97(对照)、74.03、148.33、213.64、335.33、618.88和910.98 mg/kg等氮等能饲料。检测饲料维生素C含量对条纹锯鮨幼鱼生长性能、血清生化指标、相关酶活性、各组织中维生素C积累量和肌肉成分的影响。试验期8周。结果表明:1)74.03 mg/kg组的增重率和特定生长率显著高于10.97、618.88和910.98 mg/kg组(P<0.05),74.03 mg/kg组的饲料系数显著低于10.97和910.98 mg/kg组(P<0.05),10.97和910.98 mg/kg组蛋白质效率显著低于74.03和618.88 mg/kg组(P<0.05),335.33 mg/kg组的肥满度显著低于74.03、148.33和213.64 mg/kg组(P<0.05)。2)10.97、74.03 mg/kg组血清总蛋白含量显著低于其他各组(P<0.05),618.88和910.98 mg/kg组血清甘油三酯含量显著低于其他各组(P<0.05),10.97 mg/kg组血清溶菌酶活性显著低于213.64、335.33、618.88、910.98 mg/kg组(P<0.05)。3)335.33 mg/kg组血清超氧化物歧化酶(SOD)活性显著高于10.97、74.03、910.98 mg/kg组(P<0.05),335.33 mg/kg组血清总抗氧化能力(T-AOC)显著高于10.97、618.88、910.98 mg/kg组(P<0.05),335.33 mg/kg组血清丙二醛(MDA)含量显著低于10.97 mg/kg组(P<0.05)。4)10.97 mg/kg组肝脏SOD和过氧化物酶(CAT)活性显著低于其他各组(P<0.05),148.33、335.33和910.98 mg/kg组肝脏MDA含量显著低于10.97 mg/kg(P<0.05)。5)74.03 mg/kg组肌肉SOD活性和T-AOC均显著高于其他各组(P<0.05)。6)213.64、335.33、618.88、910.98 mg/kg组血清谷丙转氨酶(GOT)活性显著低于10.97 mg/kg组(P<0.05),10.97 mg/kg组肝脏GOT活性显著低于其他各组(P<0.05)。10.97、74.03 mg/kg组血清谷草转氨酶(GPT)活性显著高于其他各组(P<0.05)。7)910.98 mg/kg组血清中维生素C积累量显著高于其他各组(P<0.05),910.98 mg/kg组肝脏中维生素C积累量显著高于10.97、74.03、148.33和213.64 mg/kg组(P<0.05),618.88 mg/kg组的肌肉中维生素C积累量显著高于10.97、74.03、148.33和213.64 mg/kg组(P<0.05)。8)74.03 mg/kg组肌肉水分含量显著低于10.97、148.33和213.64 mg/kg组(P<0.05),910.98 mg/kg组肌肉胶原蛋白含量显著高于其他各组(P<0.05)。由此可见,以特定生长率、肝脏中维生素C积累量和血清溶菌酶活性为评价标准,通过折线回归模型得出条纹锯鮨幼鱼饲料维生素C需要量分别为66.66、309.93和345.11 mg/kg

submitted time 2018-12-25 From cooperative journals:《动物营养学报》 Hits1380Downloads289 Comment 0

8. chinaXiv:201812.00648 [pdf]

胍基乙酸的生理作用和机理及其在肉鸡、猪生产方面的应用

班博; 蒋庆友; 杨泰; 田科雄
Subjects: Biology >> Zoology

胍基乙酸作为一种新型营养性饲料添加剂,对提高肉鸡和猪生产性能、促进能量代谢、加速蛋白质沉积、提高抗氧化能力、改善肉品质等方面具有一定效果。本文综述了胍基乙酸的代谢途径、生理作用及其机理,以及其在肉鸡和猪生产性能、肉品质方面的最新研究进展,以期为胍基乙酸的进一步研究和探索提供参考。

submitted time 2018-12-25 From cooperative journals:《动物营养学报》 Hits1898Downloads970 Comment 0

9. chinaXiv:201812.00649 [pdf]

芳香烃受体调控肠道炎症的研究进展

李成良; 齐广海; 彭鹏; 方热军
Subjects: Biology >> Zoology

芳香烃受体(AhR)是一种需配体激活的转录因子,对环境毒素、机体异物质代谢和免疫调节等具有重要作用。近年研究发现,AhR是参与免疫调控的关键因子,其对炎症性肠道疾病(IBD)的调控已成为当前研究热点。本文综述了AhR结构、配体、信号传导通路及AhR参与调控肠道炎症的最新研究进展,为治疗IBD提供新的思路。

submitted time 2018-12-25 From cooperative journals:《动物营养学报》 Hits1415Downloads238 Comment 0

10. chinaXiv:201812.00650 [pdf]

高产纤维分解酶康氏木霉诱变选育与发酵条件优化

朱玉霞; 高爱琴; 张铁鹰; 刘俊丽; 刘欣彤; 张志鹏; 廖朝勇
Subjects: Biology >> Zoology

本试验旨在研究高产纤维分解酶康氏木霉诱变选育与发酵条件优化。通过对康氏木霉诱变选育(紫外、硫酸二乙酯、紫外-硫酸二乙酯复合诱变),获得产纤维分解酶高的突变菌,并对其产酶发酵条件和水解秸秆能力进行研究。结果表明:康氏木霉原菌经紫外、硫酸二乙酯、紫外-硫酸二乙酯复合诱变筛选出了1株突变菌康氏木霉UH-1;与原菌相比,突变菌木聚糖酶活性提高了42.7%,纤维素酶活性提高了78.5%。康氏木霉UH-1最适固态发酵产酶条件为玉米秸秆:麸皮为7:3、硫酸铵浓度2%、接种量1.1 mL、培养基含水量67%、发酵时间84 h、磷酸二氢钾浓度1%。在此条件下滤纸酶活性达到0.86 U/g,纤维素酶活性达到99.81 U/g,木聚糖酶活性达到1 150.32 U/g;而康氏木霉原菌滤纸酶活性为0.23 U/g,纤维素酶活性为46.38 U/g,木聚糖酶活性为677.86 U/g。本研究表明,紫外-硫酸二乙酯复合诱变可有效对康氏木霉进行诱变育种,改善其产酶能力和秸秆水解能力。

submitted time 2018-12-25 From cooperative journals:《动物营养学报》 Hits1228Downloads191 Comment 0

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