The Intersexual Differences of Sexual Dimorphism,Feeding Habits and Locomotor Performance at Different Temperatures of Southern Grass Lizard(Takydromus sexlineatus) in Zhaoqing,China

通过测量头、尾、体和胃检,研究肇庆南草蜥TAkydrOMuS SEXlInEATuS个体发育过程中两性异形和食性差异。南草蜥成体个体两性大小无显著差异,雄性头部显著大于雌性,两性头部大小异形可能是受到性选择压力的结果。雌雄个体食物生态位重叠度较高,两性生态位差异微弱,食性差异与两性头部异形无明显相关性。通过设计13种不同的环境温度,研究体温变化对南草蜥两性个体运动能力表现的影响。结果显示环境温度通过影响体温而影响南草蜥的运动表现,两性个体疾跑速均具有在低体温范围内随体温升高而加快、在高体温范围内随体温升高而降低的模式。在多数测试温度下,雄体的疾跑速均略大于雌体,但两者平均值在统计上无显著差异。体温对南草蜥的最大持续运动距离和停顿次数的影响显著,两性个体的疾跑速和最大持续运动距离呈显著正相关。雄性和雌性分别在26℃和30℃具有最佳的运动表现。Southern grass lizard( Takydromus sexlineatus) was collected from Zhaoqing,Guandong province to determine the sexual dimorphism and dietary habits by measuring the lengths of head,tail and body,and examining the items in the stomach.The results showed that there was no significant difference in body size.However,male individuals had significantly larger head size than females,which might be due to the divergent sexual selection pressure.A relatively high food niche overlap was observed between the sexes.There was little relationship between food habits and head dimorphism.By designing 13 different ambient temperatures,we determined the relationship between body temperature and locomotor performance of the adults.Ambient temperature affected locomotor performance by influencing the body temperature.Sprint speed increased with increasing body temperature at lower body temperature,while decreasing with increasing body temperatures at higher body temperatures,which was similar between the sexes.However,males ran slightly faster than females in most cases,but intersexual difference of sprint speed was not statistically significant.Body temperature also influenced the maximal move distance and pause times.Sprint speed was positively correlated with the maximal move distance.The optimal temperatures of locomotor performance differed between the sexes: about 26℃ for males and 30 ℃ for females,respectively.国家自然科学基金资助项目(31271124); 广东省自然科学基金(06300177); 广东省高等教育教学改革项目(粤财教[2012]361号); 大学生创新性实验计划项目(DC201316)共同资

The Intersexual Differences of Sexual Dimorphism,Feeding Habits and Locomotor Performance at Different Temperatures of Southern Grass Lizard(Takydromus sexlineatus) in Zhaoqing,China

通过测量头、尾、体和胃检,研究肇庆南草蜥TAkydrOMuS SEXlInEATuS个体发育过程中两性异形和食性差异。南草蜥成体个体两性大小无显著差异,雄性头部显著大于雌性,两性头部大小异形可能是受到性选择压力的结果。雌雄个体食物生态位重叠度较高,两性生态位差异微弱,食性差异与两性头部异形无明显相关性。通过设计13种不同的环境温度,研究体温变化对南草蜥两性个体运动能力表现的影响。结果显示环境温度通过影响体温而影响南草蜥的运动表现,两性个体疾跑速均具有在低体温范围内随体温升高而加快、在高体温范围内随体温升高而降低的模式。在多数测试温度下,雄体的疾跑速均略大于雌体,但两者平均值在统计上无显著差异。体温对南草蜥的最大持续运动距离和停顿次数的影响显著,两性个体的疾跑速和最大持续运动距离呈显著正相关。雄性和雌性分别在26℃和30℃具有最佳的运动表现。Southern grass lizard( Takydromus sexlineatus) was collected from Zhaoqing,Guandong province to determine the sexual dimorphism and dietary habits by measuring the lengths of head,tail and body,and examining the items in the stomach.The results showed that there was no significant difference in body size.However,male individuals had significantly larger head size than females,which might be due to the divergent sexual selection pressure.A relatively high food niche overlap was observed between the sexes.There was little relationship between food habits and head dimorphism.By designing 13 different ambient temperatures,we determined the relationship between body temperature and locomotor performance of the adults.Ambient temperature affected locomotor performance by influencing the body temperature.Sprint speed increased with increasing body temperature at lower body temperature,while decreasing with increasing body temperatures at higher body temperatures,which was similar between the sexes.However,males ran slightly faster than females in most cases,but intersexual difference of sprint speed was not statistically significant.Body temperature also influenced the maximal move distance and pause times.Sprint speed was positively correlated with the maximal move distance.The optimal temperatures of locomotor performance differed between the sexes: about 26℃ for males and 30 ℃ for females,respectively.国家自然科学基金资助项目(31271124); 广东省自然科学基金(06300177); 广东省高等教育教学改革项目(粤财教[2012]361号); 大学生创新性实验计划项目(DC201316)共同资

Probing the edge-related properties of atomically thin MoS2 at nanoscale

层状二维材料具有独特的物理化学性质，使其在光电器件、传感、能源和催化等领域得到了高度关注和广泛应用。二维材料在制备过程中不可避免引入结构缺陷，虽然这些缺陷尺度仅为数纳米甚至单原子，但是会极大地改变材料的结构和电子性质，从而影响其应用。化学化工学院任斌教授课题组在层状二维材料缺陷表征方面取得进展。该工作表明了TERS在原位、高空间分辨表征缺陷位的结构和电子性质方面具有独特的优势，可以进一步推广到其他二维材料，从而有效地指导缺陷设计和材料应用。 该工作通过校内外课题组紧密合作，在任斌教授、谭平恒研究员（中科院半导体研究所）和王翔博士共同指导下完成。实验部分主要由黄腾翔博士（第一作者，已毕业化学系博士生）完成，电子能带结构与光谱理论计算由谭平恒研究员课题组从鑫博士生（共同第一作者）完成，吴思思、林楷强、姚旭、何玉韩、吴江滨、包一凡、黄声超等参与了实验与讨论。【Abstract】Defects can induce drastic changes of the electronic properties of two-dimensional transition metal dichalcogenides and influence their applications. It is still a great challenge to characterize small defects and correlate their structures with properties. Here, we show that tipenhanced Raman spectroscopy (TERS) can obtain distinctly different Raman features of edge defects in atomically thin MoS2, which allows us to probe their unique electronic properties and identify defect types (e.g., armchair and zigzag edges) in ambient. We observed an edgeinduced Raman peak (396 cm−1) activated by the double resonance Raman scattering (DRRS) process and revealed electron–phonon interaction in edges. We further visualize the edge-induced band bending region by using this DRRS peak and electronic transition region using the electron density-sensitive Raman peak at 406 cm−1. The power of TERS demonstrated in MoS2 can also be extended to other 2D materials, which may guide the defect engineering for desired properties.The authors acknowledge the final supports from MOST of China (2016YFA0200601 and 2016YFA0301204), NSFC (21633005, 21790354, 21503181, 21711530704, 21621091, 11874350, 11474277, and 11434010), Natural Science Foundation of Fujian Province (2016J05046), and China Postdoctoral Science Foundation (2017M622062). 研究工作得到科技部、国家自然科学基金委员会、福建省自然科学基金和中国博士后基金资助

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies