Humanin is a potential therapeutic agent for Alzheimer’s disease, and its derivative, S14G-humanin, is 1 000-fold stronger in its neuroprotective effect against Alzheimer’s disease-relevant insults. Alt-hough effect...Humanin is a potential therapeutic agent for Alzheimer’s disease, and its derivative, S14G-humanin, is 1 000-fold stronger in its neuroprotective effect against Alzheimer’s disease-relevant insults. Alt-hough effective, the detailed molecular mechanism through which S14G-humanin exerts its effects remains unclear. Data from this study showed that fibril ar amyloid-beta 40 disturbed cel ular ho-meostasis through the cel membrane, increasing intracel ular calcium, generating reactive oxygen species, and decreasing the mitochondrial membrane potential. S14G-humanin restored these re-sponses. The results suggested that S14G-humanin blocked the effects of amyloid-beta 40 on the neuronal cel membrane, and restored the disturbed cel ular homeostasis, thereby exerting a neuroprotective effect on hippocampal neurons.展开更多
Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus ...Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus while performing any particular activity whether it is physical or mental and this decreases one’s motivation to complete the task at hand efficiently and successfully. In the same line of thought, myriads of research studies posited the negative effects of fatigue on mental performance, and most techniques to induce fatigue to require normally long-time and repetitive visual search tasks. In this study, a visual search algorithm task was devised and customized using performance measures such as <em>d</em>’ (<strong>d-prime</strong>) and Speed Accuracy Trade-Off (<strong>SATF</strong>) as well as <strong>ROC</strong> analysis for classifier performance. The visual search algorithm consisted of distractors (<strong>L</strong>) and a target (<strong>T</strong>) whereby human participants had to press the appropriate keyboard button as fast as possible if they notice a target or not upon presentation of a visual stimulus. It was administered to human participants under laboratory conditions, and the reaction times, as well as accuracy of the participants, were monitored. It was found that the test image Size35Int255 was the best image to be used in terms of sensitivity and AUC (Area under Curve). Therefore, ongoing researches can use these findings to create their visual stimuli in such a way that the target and distractor images follow the size and intensity characteristics as found in this research.展开更多
直接乙醇燃料电池的效率与阳极乙醇氧化反应(EOR)C1路径选择性密切相关,然而C-C键断裂的能垒较高,使得C1路径产物选择性低,从而限制了直接乙醇燃料电池效率的提升.设计具有高C-C裂解效率的电催化剂,对于构建高效直接乙醇燃料电池具有重...直接乙醇燃料电池的效率与阳极乙醇氧化反应(EOR)C1路径选择性密切相关,然而C-C键断裂的能垒较高,使得C1路径产物选择性低,从而限制了直接乙醇燃料电池效率的提升.设计具有高C-C裂解效率的电催化剂,对于构建高效直接乙醇燃料电池具有重要意义.本文报道了一种Mott-Schottky异质结调节催化活性中心电子状态从而促进EOR过程中C-C裂解的新策略.我们以PdAu合金纳米颗粒(NPs)为模型催化剂,制备了PdAu@N_(x)C金属-碳Mott-Schottky异质结构.PdAu NPs(15.9±1.9 nm)均匀地分散在N掺杂的碳载体上.我们通过在宽范围内调节N掺杂量,调控异质结界面电势,形成了不同程度的电荷分离.通过催化剂结构与性能研究,建立了反应活性与催化剂功函数之间的线性关系,表明金属/碳界面电子转移可以有效促进EOR.优化的催化剂PdAu@N10.69C,显示出高C1产物选择性(FE=51.1%),质量活性(MA=9.7 A mg Pd^(-1))和比活性(SA=13.2 mA cm^(-2)),优于PdAu@C和大多数报道的Pd基EOR催化剂.实验结果和理论计算表明,N的引入促进了电子由碳层向PdAu转移,加强了对*CH_(3)CO的吸附,从而提高了C-C键的断裂效率.这项工作为整流策略提高EOR性能提供了一种新的研究思路.展开更多
A dating of two biotite samples taken from the meso- and low-temperature myloniteswithin the Shangyi-Chicheng fault belt on the north of the North China Craton yields 40Ar/39Ar iso-topic ages of (399 1) Ma and (263 2)...A dating of two biotite samples taken from the meso- and low-temperature myloniteswithin the Shangyi-Chicheng fault belt on the north of the North China Craton yields 40Ar/39Ar iso-topic ages of (399 1) Ma and (263 2) Ma, respectively. These data reflect an Early Devonian deformation and a Late Carboniferous retrograde metamorphism event along the fault, suggesting that the tectonic activities of the North China Craton in Paleozoic should be reconsidered.展开更多
gHighly optically active 4-substituted-2(5H)-furanones 6a—6j were obtained in good yields with de≥98% by the tandem Michael addition/elimination reaction of chiral 3-bromo-2(5H)-furanone (4a), which was conveniently...gHighly optically active 4-substituted-2(5H)-furanones 6a—6j were obtained in good yields with de≥98% by the tandem Michael addition/elimination reaction of chiral 3-bromo-2(5H)-furanone (4a), which was conveniently prepared starting from 2-furaldehyde under mild conditions. The products were identified on the basis of their sat-isfactory elemental analysis and spectroscopic data of IR, UV, 1H NMR, 13C NMR and mass spectra. The stereo-chemistry and absolute configuration of this type of compounds were established by the X-ray crystallographic study. The reaction provided a short and efficient synthesis of the interesting highly optically active 4-substituted-2(5H)-furanones containing an active pyrimidine and a purine base group.展开更多
基金supported by grants from Henan Medical Technologies R&D Program in China,No.200703023,201203130Henan Key Science and Technology Project in China,No.112102310684
文摘Humanin is a potential therapeutic agent for Alzheimer’s disease, and its derivative, S14G-humanin, is 1 000-fold stronger in its neuroprotective effect against Alzheimer’s disease-relevant insults. Alt-hough effective, the detailed molecular mechanism through which S14G-humanin exerts its effects remains unclear. Data from this study showed that fibril ar amyloid-beta 40 disturbed cel ular ho-meostasis through the cel membrane, increasing intracel ular calcium, generating reactive oxygen species, and decreasing the mitochondrial membrane potential. S14G-humanin restored these re-sponses. The results suggested that S14G-humanin blocked the effects of amyloid-beta 40 on the neuronal cel membrane, and restored the disturbed cel ular homeostasis, thereby exerting a neuroprotective effect on hippocampal neurons.
文摘Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus while performing any particular activity whether it is physical or mental and this decreases one’s motivation to complete the task at hand efficiently and successfully. In the same line of thought, myriads of research studies posited the negative effects of fatigue on mental performance, and most techniques to induce fatigue to require normally long-time and repetitive visual search tasks. In this study, a visual search algorithm task was devised and customized using performance measures such as <em>d</em>’ (<strong>d-prime</strong>) and Speed Accuracy Trade-Off (<strong>SATF</strong>) as well as <strong>ROC</strong> analysis for classifier performance. The visual search algorithm consisted of distractors (<strong>L</strong>) and a target (<strong>T</strong>) whereby human participants had to press the appropriate keyboard button as fast as possible if they notice a target or not upon presentation of a visual stimulus. It was administered to human participants under laboratory conditions, and the reaction times, as well as accuracy of the participants, were monitored. It was found that the test image Size35Int255 was the best image to be used in terms of sensitivity and AUC (Area under Curve). Therefore, ongoing researches can use these findings to create their visual stimuli in such a way that the target and distractor images follow the size and intensity characteristics as found in this research.
基金supported by the National Natural Science Foundation of China(22278108,22008048)the Hundred Talents Project of Hebei Province(E2019050015)+3 种基金the Natural Science Foundation of Tianjin(22JCYBJC00250)the Natural Science Foundation for Outstanding Youth Scholars of Hebei Province(B2021202061)the Natural Science Foundation of Hebei Province(B2021202010)the State Key Laboratory of Fine Chemicals,Dalian University of Technology(KF 2108)。
文摘直接乙醇燃料电池的效率与阳极乙醇氧化反应(EOR)C1路径选择性密切相关,然而C-C键断裂的能垒较高,使得C1路径产物选择性低,从而限制了直接乙醇燃料电池效率的提升.设计具有高C-C裂解效率的电催化剂,对于构建高效直接乙醇燃料电池具有重要意义.本文报道了一种Mott-Schottky异质结调节催化活性中心电子状态从而促进EOR过程中C-C裂解的新策略.我们以PdAu合金纳米颗粒(NPs)为模型催化剂,制备了PdAu@N_(x)C金属-碳Mott-Schottky异质结构.PdAu NPs(15.9±1.9 nm)均匀地分散在N掺杂的碳载体上.我们通过在宽范围内调节N掺杂量,调控异质结界面电势,形成了不同程度的电荷分离.通过催化剂结构与性能研究,建立了反应活性与催化剂功函数之间的线性关系,表明金属/碳界面电子转移可以有效促进EOR.优化的催化剂PdAu@N10.69C,显示出高C1产物选择性(FE=51.1%),质量活性(MA=9.7 A mg Pd^(-1))和比活性(SA=13.2 mA cm^(-2)),优于PdAu@C和大多数报道的Pd基EOR催化剂.实验结果和理论计算表明,N的引入促进了电子由碳层向PdAu转移,加强了对*CH_(3)CO的吸附,从而提高了C-C键的断裂效率.这项工作为整流策略提高EOR性能提供了一种新的研究思路.
基金the National Natural Science Foundation of China(Grant No.49772148) the Open Lab of the Geo-dynamics(Grant No.dlkf-9802) under the administration of the Ministry of Geology and Mineral Resources of China.
文摘A dating of two biotite samples taken from the meso- and low-temperature myloniteswithin the Shangyi-Chicheng fault belt on the north of the North China Craton yields 40Ar/39Ar iso-topic ages of (399 1) Ma and (263 2) Ma, respectively. These data reflect an Early Devonian deformation and a Late Carboniferous retrograde metamorphism event along the fault, suggesting that the tectonic activities of the North China Craton in Paleozoic should be reconsidered.
基金Project supported by the National Natural Science Foundation of China (No. 29672004).
文摘gHighly optically active 4-substituted-2(5H)-furanones 6a—6j were obtained in good yields with de≥98% by the tandem Michael addition/elimination reaction of chiral 3-bromo-2(5H)-furanone (4a), which was conveniently prepared starting from 2-furaldehyde under mild conditions. The products were identified on the basis of their sat-isfactory elemental analysis and spectroscopic data of IR, UV, 1H NMR, 13C NMR and mass spectra. The stereo-chemistry and absolute configuration of this type of compounds were established by the X-ray crystallographic study. The reaction provided a short and efficient synthesis of the interesting highly optically active 4-substituted-2(5H)-furanones containing an active pyrimidine and a purine base group.