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1. chinaXiv:202009.00049 [pdf]

New fossils of Late Pleistocene Sus scrofa from Yangjiawan Cave 2, Jiangxi, China

SUN Ji-Jia; ZHANG Bei; CHEN Xi; DENG Li; ?WEN Jun; TONG Hao-Wen
Subjects: Biology >> Zoology

The YJW (Yangjiawan) Cave 2 of Pingxiang in Jiangxi Province is a karst cave that?developed in the Permian limestone of the Changxing Formation, which is filled with clay and?grit of Late Pleistocene age. Six excavations have been conducted at the site since 2015. More?than ten thousand mammalian fossils have been unearthed, and the wild boar fossils account for?approximately 49%, which represents the richest wild boar fossil tooth collection of Pleistocene?age in southern China. This study focuses on the studies of the canine teeth and the third molars,?and mainly compares fossils of Sus peii and S. xiaozhu in South China and the data of extant S.?scrofa respectively in dental morphology and odontometric data analyses which includes scatter?plot analysis, regression analysis, coefficient of variation analysis and linear discriminant analysis.?The typical scrofic type of the male’s lower canine teeth confirmed the identification of the suid?fossils from YJW Cave 2 as S. scrofa. Although the male’s lower canines, the M2s and m3s,?are among the most variable teeth in sizes, they stay in the ranges of S. scrofa; furthermore, the?scatterplots of both the upper and lower third molars form two distinct clusters respectively, which?can probably be attributed to sexual dimorphism rather than resulting from a mixture of different?suid species. The post-Early Pleistocene suid fauna in southern China is almost only composed of?S. scrofa, which is quite different from the adjacent Southeast Asia where the suid fauna is quite?taxonomically diversified and dominated by the verrucosic type.

submitted time 2020-09-15 From cooperative journals:《古脊椎动物学报》 Hits116Downloads57 Comment 0

2. chinaXiv:202005.00090 [pdf]

Spatial and temporal change patterns of net primary productivity and its response to climate change in the Qinghai–Tibet Plateau of China from 2000 to 2015

GUO Bing; ZANG Wenqian6, YANG Fei; HAN Baomin; CHEN Shuting; LIU Yue; YANG Xiao; HE Tianli; CHEN Xi; LIU Chunting; GONG Rui
Subjects: Biology >> Botany >> Applied botany

The vegetation ecosystem of the Qinghai–Tibet Plateau in China, considered to be the ′′natural laboratory′′ of climate change in the world, has undergone profound changes under the stress of global change. Herein, we analyzed and discussed the spatial-temporal change patterns and the driving mechanisms of net primary productivity (NPP) in the Qinghai–Tibet Plateau from 2000 to 2015 based on the gravity center and correlation coefficient models. Subsequently, we quantitatively distinguished the relative effects of climate change (such as precipitation, temperature and evapotranspiration) and human activities (such as grazing and ecological construction) on the NPP changes using scenario analysis and Miami model based on the MOD17A3 and meteorological data. The average annual NPP in the Qinghai–Tibet Plateau showed a decreasing trend from the southeast to the northwest during 2000–2015. With respect to the inter-annual changes, the average annual NPP exhibited a fluctuating upward trend from 2000 to 2015, with a steep increase observed in 2005 and a high fluctuation observed from 2005 to 2015. In the Qinghai–Tibet Plateau, the regions with the increase in NPP (change rate higher than 10%) were mainly concentrated in the Three-River Source Region, the northern Hengduan Mountains, the middle and lower reaches of the Yarlung Zangbo River, and the eastern parts of the North Tibet Plateau, whereas the regions with the decrease in NPP (change rate lower than –10%) were mainly concentrated in the upper reaches of the Yarlung Zangbo River and the Ali Plateau. The gravity center of NPP in the Qinghai–Tibet Plateau has moved southwestward during 2000–2015, indicating that the increment and growth rate of NPP in the southwestern part is greater than those of NPP in the northeastern part.Further, a significant correlation was observed between NPP and climate factors in the Qinghai–Tibet Plateau. The regions exhibiting a significant correlation between NPP and precipitation were mainly located in the central and eastern Qinghai–Tibet Plateau, and the regions exhibiting a significant correlation between NPP and temperature were mainly located in the southern and eastern Qinghai–Tibet Plateau. Furthermore, the relative effects of climate change and human activities on the NPP changes in the Qinghai–Tibet Plateau exhibited significant spatial differences in three types of zones, i.e., the climate change-dominant zone, the human activity-dominant zone, and the climate change and human activity interaction zone. These research results can provide theoretical and methodological supports to reveal the driving mechanisms of the regional ecosystems to the global change in the Qinghai–Tibet Plateau.

submitted time 2020-05-31 From cooperative journals:《Journal of Arid Land》 Hits10584Downloads593 Comment 0

3. chinaXiv:201605.01359 [pdf]

Microcirculation Dysfunction in Age-related Cognitive Impairment

Chen Xi-Xi; Su Tao; Chen Xi-Xi
Subjects: Biology >> Biophysics >> Biochemistry & Molecular Biology

Microcirculation dysfunction is regarded as one of important pathologies of senility, degeneration, immune disorder and many other diseases. Cerebral circulation insufficiency, energetic dysmetabolism, hypoxia-ischemia and metabolites accumulation in Alzheimer's disease (AD) have a close relation with microcirculation dysfunction. Here, we review microcirculation dysfunction playing an important role in hyperphosphorylation of Tau, A beta aggregation and cognitive impairment induced by accumulation of formaldehyde and D-ribose.

submitted time 2016-05-11 Hits971Downloads422 Comment 0

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