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亲子关系与CLOCK基因rs1801260多态性对学前儿童亲社会行为的交互影响:性别的调节作用
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作者 刘倩文 高晗晶 王振宏 《心理发展与教育》 CSSCI 北大核心 2024年第5期625-635,共11页
研究探讨了亲子关系与CLOCK基因rs1801260多态性对学前儿童亲社会行为的交互影响及性别的调节作用。以694名学前儿童(M_(年龄)=5.06岁,SD=0.87)及其父母为测试对象,收集儿童的唾液样本进行基因分型,由儿童父母填写亲子关系和儿童亲社会... 研究探讨了亲子关系与CLOCK基因rs1801260多态性对学前儿童亲社会行为的交互影响及性别的调节作用。以694名学前儿童(M_(年龄)=5.06岁,SD=0.87)及其父母为测试对象,收集儿童的唾液样本进行基因分型,由儿童父母填写亲子关系和儿童亲社会行为量表。研究结果发现,亲子亲密与亲子冲突对亲社会行为的主效应显著。亲子冲突、CLOCK基因rs1801260多态性和性别三重交互影响儿童的亲社会行为,即与携带C等位基因的男孩相比,携带TT基因型的男孩在低亲子冲突下会表现出更多的亲社会行为,在高亲子冲突下则表现出更少的亲社会行为。但亲子冲突与CLOCK基因rs1801260多态性对女孩亲社会行为的交互作用不显著。研究结果为深入理解学前儿童亲社会行为形成的基因-环境交互作用机制提供了证据。 展开更多
关键词 学前儿童 亲子冲突 clock基因rs1801260多态性 亲社会行为 个体(基因)-环境交互
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Novel umami peptides from two Termitomyces mushrooms and molecular docking to the taste receptor T1R1/T1R3 被引量:4
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作者 Lanyun Zhang Li Zhang +3 位作者 Jesus Pérez-Moreno Lu Bin Fengming Zhang Fuqiang Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1055-1064,共10页
Wild edible Termitomyces mushrooms are popular in Southwest China and umami is important flavor qualities of edible mushrooms.This study aimed to understand the umami taste of Termitomyces intermedius and Termitomyces... Wild edible Termitomyces mushrooms are popular in Southwest China and umami is important flavor qualities of edible mushrooms.This study aimed to understand the umami taste of Termitomyces intermedius and Termitomyces aff.bulborhizus.Ten umami peptides from aqueous extracts were separated using a Sephadex G-15 gel filtration chromatography.The intense umami fraction was evaluated by both sensory evaluation and electronic tongue.They were identified as KLNDAQAPK,DSTDEKFLR,VGKGAHLSGEH,MLKKKKLA,SLGFGGPPGY,TVATFSSSTKPDD,AMDDDEADLLLLAM,VEDEDEKPKEK,SPEEKKEEET and PEGADKPNK.Seven peptides,except VEDEDEKPKEK,SPEEKKEEET and PEGADKPNK were selectively synthesized to verify their taste characteristics.All these 10 peptides had umami or salt taste.The 10 peptides were conducted by molecular docking to study their interaction with identified peptides and the umami taste receptor T1R1/T1R3.All these 10 peptides perfectly docked the active residues in the T1R3 subunit.Our results provide theoretical basis for the umami taste and address the umami mechanism of two wild edible Termitomyces mushrooms. 展开更多
关键词 TERMITOMYCES Non-volatile flavor compounds Umami peptides Taste characteristics molecular docking
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Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants 被引量:1
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作者 Su Shuo Long Jun +2 位作者 Duan Qinghua Zhou Han Zhao Yi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期135-145,共11页
To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular me... To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular simulations.Calculation results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen peroxide.Based on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur atoms.Experimental results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions. 展开更多
关键词 lubricating oil ANTIOXIDANT molecular mechanism molecular design antioxidant performance
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A frequency servo SoC with output power stabilization loop technology for miniaturized atomic clocks 被引量:1
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作者 Hongyang Zhang Xinlin Geng +3 位作者 Zonglin Ye Kailei Wang Qian Xie Zheng Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期13-22,共10页
A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL... A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL)technique,incorporating an off-chip power detector(PD),ensures that the output power of the FS-SoC remains stable,mitigating the impact of power fluctuations on the atomic clock's stability.Additionally,a one-pulse-per-second(1PPS)is employed to syn-chronize the clock with GPS.Fabricated using 65 nm CMOS technology,the measured phase noise of the FS-SoC stands at-69.5 dBc/Hz@100 Hz offset and-83.9 dBc/Hz@1 kHz offset,accompanied by a power dissipation of 19.7 mW.The Cs atomic clock employing the proposed FS-SoC and PSL obtains an Allan deviation of 1.7×10^(-11) with 1-s averaging time. 展开更多
关键词 CMOS technology atomic clock phase-locked loop output power stabilization 1PPS
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Molecular mechanisms underlying microglial sensing and phagocytosis in synaptic pruning 被引量:2
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作者 Anran Huo Jiali Wang +6 位作者 Qi Li Mengqi Li Yuwan Qi Qiao Yin Weifeng Luo Jijun Shi Qifei Cong 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1284-1290,共7页
Microglia are the main non-neuronal cells in the central nervous system that have important roles in brain development and functional connectivity of neural circuits.In brain physiology,highly dynamic microglial proce... Microglia are the main non-neuronal cells in the central nervous system that have important roles in brain development and functional connectivity of neural circuits.In brain physiology,highly dynamic microglial processes are facilitated to sense the surrounding environment and stimuli.Once the brain switches its functional states,microglia are recruited to specific sites to exert their immune functions,including the release of cytokines and phagocytosis of cellular debris.The crosstalk of microglia between neurons,neural stem cells,endothelial cells,oligodendrocytes,and astrocytes contributes to their functions in synapse pruning,neurogenesis,vascularization,myelination,and blood-brain barrier permeability.In this review,we highlight the neuron-derived“find-me,”“eat-me,”and“don't eat-me”molecular signals that drive microglia in response to changes in neuronal activity for synapse refinement during brain development.This review reveals the molecular mechanism of neuron-microglia interaction in synaptic pruning and presents novel ideas for the synaptic pruning of microglia in disease,thereby providing important clues for discovery of target drugs and development of nervous system disease treatment methods targeting synaptic dysfunction. 展开更多
关键词 COMPLEMENT immune signals microglia molecular signal synapse elimination synapse formation synapse refinement synaptic pruning
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Analysis of CH_(4) and H_(2) Adsorption on Heterogeneous Shale Surfaces Using aMolecular Dynamics Approach 被引量:1
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作者 Surajudeen Sikiru Hassan Soleimani +2 位作者 Amir Rostami Mohammed Falalu Hamza Lukmon Owolabi Afolabi 《Fluid Dynamics & Materials Processing》 EI 2024年第1期31-44,共14页
Determining the adsorption of shale gas on complex surfaces remains a challenge in molecular simulation studies.Difficulties essentially stem from the need to create a realistic shale structure model in terms of miner... Determining the adsorption of shale gas on complex surfaces remains a challenge in molecular simulation studies.Difficulties essentially stem from the need to create a realistic shale structure model in terms of mineral heterogeneityand multiplicity.Moreover,precise characterization of the competitive adsorption of hydrogen andmethane in shale generally requires the experimental determination of the related adsorptive capacity.In thisstudy,the adsorption of adsorbates,methane(CH_(4)),and hydrogen(H_(2))on heterogeneous shale surface modelsof Kaolinite,Orthoclase,Muscovite,Mica,C_(60),and Butane has been simulated in the frame of a moleculardynamic’s numerical technique.The results show that these behaviors are influenced by pressure and potentialenergy.On increasing the pressure from 500 to 2000 psi,the sorption effect for CH_(4)significantly increasesbut shows a decline at a certain stage(if compared to H_(2)).The research findings also indicate that raw shalehas a higher capacity to adsorb CH_(4)compared to hydrogen.However,in shale,this difference is negligible. 展开更多
关键词 Shale gas ADSORPTION METHANE hydrogen molecular dynamic SORPTION
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Facile synthesis of Cu-doped manganese oxide octahedral molecular sieve for the efficient degradation of sulfamethoxazole via peroxymonosulfate activation 被引量:1
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作者 Yuhua Qiu Yingping Huang +2 位作者 Yanlan Wang Xiang Liu Di Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2770-2780,共11页
Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive speci... Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive species,including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radical(·O_(2)^(-)),and singlet oxygen(1O_(2)),which can induce the degradation of organic contaminants.In this work,we synthesized a variety of M-OMS-2 nanorods(M=Co,Ni,Cu,Fe)by doping Co^(2+),Ni^(2+),Cu^(2+),or Fe^(3+)into manganese oxide oc-tahedral molecular sieve(OMS-2)to efficiently remove sulfamethoxazole(SMX)via PMS activation.The catalytic performance of M-OMS-2 in SMX elimination via PMS activation was assessed.The nanorods obtained in decreasing order of SMX removal rate were Cu-OMS-2(96.40%),Co-OMS-2(88.00%),Ni-OMS-2(87.20%),Fe-OMS-2(35.00%),and OMS-2(33.50%).Then,the kinetics and struc-ture-activity relationship of the M-OMS-2 nanorods during the elimination of SMX were investigated.The feasible mechanism underly-ing SMX degradation by the Cu-OMS-2/PMS system was further investigated with a quenching experiment,high-resolution mass spec-troscopy,and electron paramagnetic resonance.Results showed that SMX degradation efficiency was enhanced in seawater and tap water,demonstrating the potential application of Cu-OMS-2/PMS system in sewage treatment. 展开更多
关键词 SULFAMETHOXAZOLE manganese oxide octahedral molecular sieve PEROXYMONOSULFATE sewage treatment COPPER
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Exploring the taste presentation and receptor perception mechanism of salty peptides from Stropharia rugosoannulata based on molecular dynamics and thermodynamics simulation 被引量:1
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作者 Wen Li Shuai Sun +6 位作者 Wanchao Chen Haile Ma Tingzhao Li Zhong Zhang Di Wu Mengqiu Yan Yan Yang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2277-2288,共12页
The taste presentation and receptor perception mechanism of the salty peptide of Stropharia rugosoannulata were predicted and verified using peptide omics and molecular interaction techniques.The combination of aspart... The taste presentation and receptor perception mechanism of the salty peptide of Stropharia rugosoannulata were predicted and verified using peptide omics and molecular interaction techniques.The combination of aspartic acid(D)and glutamic acid(E),or peptide fragments composed of arginine(R),constitute the characteristic taste structural basis of salty peptides of S.rugosoannulata.The taste intensity of the salty peptide positively correlates with its concentration within a specific concentration range(0.25–1.0 mg/mL).The receptor more easily recognizes the first amino acid residue at the N-terminal of salty peptides and the aspartic acid residue in the peptides.GLU513,ASP707,and VAL508 are the critical amino acid residues for the receptor to recognize salty peptides.TRPV1 is specifically the receptor for recognizing salty peptides.Hydrogen bonds and electrostatic interactions are the main driving forces for the interactions between salty peptides and TRPV1 receptors.KSWDDFFTR has the most potent binding capacity with the receptor and has tremendous potential for application in sodium salt substitution.This study confirmed the taste receptor that specifically recognizes salty peptides,analyzed the receptor-peptide binding interaction,and provided a new idea for understanding the taste receptor perception of salty peptides. 展开更多
关键词 Salty peptide molecular docking Biolayer interferometry Isothermal titration calorimetry
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Hypothalamic circuits and aging:keeping the circadian clock updated 被引量:1
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作者 Rosa Vázquez-Lizarraga Lucia Mendoza-Viveros +3 位作者 Carolina Cid-Castro Sareni Ruiz-Montoya Erick Carreño-Vázquez Ricardo Orozco-Solis 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1919-1928,共10页
Over the past century,age-related diseases,such as cancer,type-2 diabetes,obesity,and mental illness,have shown a significant increase,negatively impacting overall quality of life.Studies on aged animal models have un... Over the past century,age-related diseases,such as cancer,type-2 diabetes,obesity,and mental illness,have shown a significant increase,negatively impacting overall quality of life.Studies on aged animal models have unveiled a progressive discoordination at multiple regulatory levels,including transcriptional,translational,and post-translational processes,resulting from cellular stress and circadian derangements.The circadian clock emerges as a key regulator,sustaining physiological homeostasis and promoting healthy aging through timely molecular coordination of pivotal cellular processes,such as stem-cell function,cellular stress responses,and inter-tissue communication,which become disrupted during aging.Given the crucial role of hypothalamic circuits in regulating organismal physiology,metabolic control,sleep homeostasis,and circadian rhythms,and their dependence on these processes,strategies aimed at enhancing hypothalamic and circadian function,including pharmacological and non-pharmacological approaches,offer systemic benefits for healthy aging.Intranasal brain-directed drug administration represents a promising avenue for effectively targeting specific brain regions,like the hypothalamus,while reducing side effects associated with systemic drug delivery,thereby presenting new therapeutic possibilities for diverse age-related conditions. 展开更多
关键词 AGING ASTROCYTES cellular stress responses circadian clock HYPOTHALAMUS intranasal drug administration metabolic control nutrient sensor SIRT1 sleep homeostasis
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Risk stratification for radioactive iodine refractoriness using molecular alterations in distant metastatic differentiated thyroid cancer 被引量:1
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作者 Zhuanzhuan Mu Xin Zhang +9 位作者 Dongquan Liang Jugao Fang Ge Chen Wenting Guo Di Sun Yuqing Sun Zhentian Kai Lisha Huang Jun Liang Yansong Lin 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第1期25-35,共11页
Objective: Patients with radioactive iodine-refractory differentiated thyroid cancer(RAIR-DTC) are often diagnosed with delay and constrained to limited treatment options. The correlation between RAI refractoriness an... Objective: Patients with radioactive iodine-refractory differentiated thyroid cancer(RAIR-DTC) are often diagnosed with delay and constrained to limited treatment options. The correlation between RAI refractoriness and the underlying genetic characteristics has not been extensively studied.Methods: Adult patients with distant metastatic DTC were enrolled and assigned to undergo next-generation sequencing of a customized 26-gene panel(Thyro Lead). Patients were classified into RAIR-DTC or non-RAIR groups to determine the differences in clinicopathological and molecular characteristics. Molecular risk stratification(MRS) was constructed based on the association between molecular alterations identified and RAI refractoriness, and the results were classified as high, intermediate or low MRS.Results: A total of 220 patients with distant metastases were included, 63.2% of whom were identified as RAIRDTC. Genetic alterations were identified in 90% of all the patients, with BRAF(59.7% vs. 17.3%), TERT promoter(43.9% vs. 7.4%), and TP53 mutations(11.5% vs. 3.7%) being more prevalent in the RAIR-DTC group than in the non-RAIR group, except for RET fusions(15.8% vs. 39.5%), which had the opposite pattern. BRAF and TERT promoter are independent predictors of RAIR-DTC, accounting for 67.6% of patients with RAIR-DTC. MRS was strongly associated with RAI refractoriness(P<0.001), with an odds ratio(OR) of high to low MRS of 7.52 [95%confidence interval(95% CI), 3.96-14.28;P<0.001] and an OR of intermediate to low MRS of 3.20(95% CI,1.01-10.14;P=0.041).Conclusions: Molecular alterations were associated with RAI refractoriness, with BRAF and TERT promoter mutations being the predominant contributors, followed by TP53 and DICER1 mutations. MRS might serve as a valuable tool for both prognosticating clinical outcomes and directing precision-based therapeutic interventions. 展开更多
关键词 Differentiated thyroid cancer distant metastases genetic alterations RAI refractoriness molecular risk stratification
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Development of in situ characterization techniques in molecular beam epitaxy 被引量:1
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作者 Chao Shen Wenkang Zhan +7 位作者 Manyang Li Zhenyu Sun Jian Tang Zhaofeng Wu Chi Xu Bo Xu Chao Zhao Zhanguo Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期9-32,共24页
Ex situ characterization techniques in molecular beam epitaxy(MBE)have inherent limitations,such as being prone to sample contamination and unstable surfaces during sample transfer from the MBE chamber.In recent years... Ex situ characterization techniques in molecular beam epitaxy(MBE)have inherent limitations,such as being prone to sample contamination and unstable surfaces during sample transfer from the MBE chamber.In recent years,the need for improved accuracy and reliability in measurement has driven the increasing adoption of in situ characterization techniques.These techniques,such as reflection high-energy electron diffraction,scanning tunneling microscopy,and X-ray photoelectron spectroscopy,allow direct observation of film growth processes in real time without exposing the sample to air,hence offering insights into the growth mechanisms of epitaxial films with controlled properties.By combining multiple in situ characterization techniques with MBE,researchers can better understand film growth processes,realizing novel materials with customized properties and extensive applications.This review aims to overview the benefits and achievements of in situ characterization techniques in MBE and their applications for material science research.In addition,through further analysis of these techniques regarding their challenges and potential solutions,particularly highlighting the assistance of machine learning to correlate in situ characterization with other material information,we hope to provide a guideline for future efforts in the development of novel monitoring and control schemes for MBE growth processes with improved material properties. 展开更多
关键词 epitaxial growth thin film in situ characterization molecular beam epitaxy(MBE)
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MEMS Huygens Clock Based on Synchronized Micromechanical Resonators
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作者 Xueyong Wei Mingke Xu +6 位作者 Qiqi Yang Liu Xu a Yonghong Qi Ziming Ren Juan Ren Ronghua Huan Zhuangde Jiang 《Engineering》 SCIE EI CAS CSCD 2024年第5期124-131,共8页
With the continuous miniaturization of electronic devices,microelectromechanical system(MEMS)oscillators that can be combined with integrated circuits have attracted increasing attention.This study reports a MEMS Huyg... With the continuous miniaturization of electronic devices,microelectromechanical system(MEMS)oscillators that can be combined with integrated circuits have attracted increasing attention.This study reports a MEMS Huygens clock based on the synchronization principle,comprising two synchronized MEMS oscillators and a frequency compensation system.The MEMS Huygens clock improved shorttime stability,improving the Allan deviation by a factor of 3.73 from 19.3 to 5.17 ppb at 1 s.A frequency compensation system based on the MEMS oscillator’s temperature-frequency characteristics was developed to compensate for the frequency shift of the MEMS Huygens clock by controlling the resonator current.This effectively improved the long-term stability of the oscillator,with the Allan deviation improving by 1.6343105 times to 30.9 ppt at 6000 s.The power consumption for compensating both oscillators simultaneously is only 2.85 mW·℃^(-1).Our comprehensive solution scheme provides a novel and precise engineering solution for achieving high-precision MEMS oscillators and extends synchronization applications in MEMS. 展开更多
关键词 Frequency stability Huygens clock MEMS OSCILLATOR SYNCHRONIZATION
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Piperine regulates the circadian rhythms of hepatic clock gene expressions and gut microbiota in high-fat diet-induced obese rats
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作者 Weiyun Zhang Chi-Tang Ho +2 位作者 Wenlian Wei Jie Xiao Muwen Lu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1617-1627,共11页
The interplay between the host circadian clock and microbiota has significant influences on host metabolism processes,and circadian desynchrony triggered by high-fat diet(HFD)is closely related to metabolic disorders.... The interplay between the host circadian clock and microbiota has significant influences on host metabolism processes,and circadian desynchrony triggered by high-fat diet(HFD)is closely related to metabolic disorders.In this study,the modulatory effects of piperine(PIP)on lipid metabolism homeostasis,gut microbiota community and circadian rhythm of hepatic clock gene expressions in obese rats were investigated.The Sprague-Dawley(SD)rats were fed with normal diet(ND),HFD and HFD supplemented with PIP,respectively.After 9 weeks,rats were sacrificed with tissue and fecal samples collected for circadian analysis.Results showed that chronic PIP administration ameliorated the obesity-induced alterations in lipid metabolism and dysregulation of hepatic clock gene expressions in obese rats.The gut microbial communities studied through 16S rRNA sequencing showed that PIP ameliorated the imbalanced nicrobiota and recovered the circadian rhythm of Lactobacillaceae,Desulfovibrionaceae,Paraprevotellaceae,and Lachnospiraceae.The fecal metabolic profiles indicated that 3-dehydroshikimate,cytidine and lithocholyltaurine were altered,which were involved in the amino acid and fatty acid metabolism process.These findings could provide theoretical basis for PIP to work as functional food to alleviate the lipid metabolism disorder,circadian rhythm misalignment,and gut microbiota dysbiosis with wide applications in the food and pharmaceutic industries. 展开更多
关键词 PIPERINE Circadian clock OBESITY Gut microbiota
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A redundant subspace weighting procedure for clock ensemble
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作者 徐海 陈煜 +1 位作者 刘默驰 王玉琢 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期435-442,共8页
A redundant-subspace-weighting(RSW)-based approach is proposed to enhance the frequency stability on a time scale of a clock ensemble.In this method,multiple overlapping subspaces are constructed in the clock ensemble... A redundant-subspace-weighting(RSW)-based approach is proposed to enhance the frequency stability on a time scale of a clock ensemble.In this method,multiple overlapping subspaces are constructed in the clock ensemble,and the weight of each clock in this ensemble is defined by using the spatial covariance matrix.The superimposition average of covariances in different subspaces reduces the correlations between clocks in the same laboratory to some extent.After optimizing the parameters of this weighting procedure,the frequency stabilities of virtual clock ensembles are significantly improved in most cases. 展开更多
关键词 weighting method redundant subspace clock ensemble time scale
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A Yb optical clock with a lattice power enhancement cavity
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作者 王春云 姚远 +3 位作者 师浩森 于洪浮 马龙生 蒋燕义 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期70-74,共5页
We construct a power enhancement cavity to form an optical lattice in an ytterbium optical clock.It is demonstrated that the intra-cavity lattice power can be increased by about 45 times,and the trap depth can be as l... We construct a power enhancement cavity to form an optical lattice in an ytterbium optical clock.It is demonstrated that the intra-cavity lattice power can be increased by about 45 times,and the trap depth can be as large as 1400Er when laser light with a power of only 0.6 W incident to the lattice cavity.Such high trap depths are the key to accurate evaluation of the lattice-induced light shift with an uncertainty down to~1×10-18.By probing the ytterbium atoms trapped in the power-enhanced optical lattice,we obtain a 4.3 Hz-linewidth Rabi spectrum,which is then used to feedback to the clock laser for the close loop operation of the optical lattice clock.We evaluate the density shift of the Yb optical lattice clock based on interleaving measurements,which is-0.46(62)mHz.This result is smaller compared to the density shift of our first Yb optical clock without lattice power enhancement cavity mainly due to a larger lattice diameter of 344μm. 展开更多
关键词 optical atomic clock optical lattice optical cavity Stark shift
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Flowering-time regulation by the circadian clock:From Arabidopsis to crops
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作者 Mingkang Yang Wenjie Lin +4 位作者 Yarou Xu Biyu Xie Baiyin Yu Liang Chen Wei Huang 《The Crop Journal》 SCIE CSCD 2024年第1期17-27,共11页
Precise timing of flowering in plants is critical for their growth and reproductive processes.One factor controlling flowering time is the cycle of light and darkness within a day,known as the photoperiod.Plants are c... Precise timing of flowering in plants is critical for their growth and reproductive processes.One factor controlling flowering time is the cycle of light and darkness within a day,known as the photoperiod.Plants are classified into long-day,short-day,and day-neutral plants based on light requirements for floral initiation.Although the molecular mechanisms that govern this differentiation remain incompletely understood,studies have consistently shown that the circadian clock plays a central role in regulating photoperiod response across diverse plant species.However,there is a scarcity of reviews describing the regulatory network linking the circadian clock with photoperiodic flowering.This review summarizes that regulatory network,focusing on the distinct roles of clock genes in long-day and short-day plants.We also discuss the strategies of clock gene mutations contributing to geographic variation in longday and short-day crops. 展开更多
关键词 Circadian clock PHOTOPERIOD Short-day plants Long-day plants
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Physics package based on intracavity laser cooling ^(87)Rb atoms for space cold atom microwave clock
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作者 邓思敏达 任伟 +9 位作者 项静峰 赵剑波 李琳 张迪 万金银 孟艳玲 蒋小军 李唐 刘亮 吕德胜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期22-26,共5页
This article proposes a new physics package to enhance the frequency stability of the space cold atom clock with the advantages of a microgravity environment. Clock working processes, including atom cooling, atomic st... This article proposes a new physics package to enhance the frequency stability of the space cold atom clock with the advantages of a microgravity environment. Clock working processes, including atom cooling, atomic state preparation,microwave interrogation, and transition probability detection, are integrated into the cylindrical microwave cavity to achieve a high-performance and compact physics package for the space cold atom clock. We present the detailed design and ground-test results of the cold atom clock physics package in this article, which demonstrates a frequency stability of 1.2×10^(-12) τ^(-1/2) with a Ramsey linewidth of 12.5 Hz, and a better performance is predicted with a 1 Hz or a narrower Ramsey linewidth in microgravity environment. The miniaturized cold atom clock based on intracavity cooling has great potential for achieving space high-precision time-frequency reference in the future. 展开更多
关键词 atomic clock MICROGRAVITY microwave cavity space station frequency stability
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A novel small-animal locomotor activity recording device for biological clock research
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作者 Yi-Long Wu Ming Zhong +5 位作者 Jun Yin Wei-Jie Ou Yu-Bin Zhuang Nan-Wen Zhang Su Lin Yue-Yong Zhu 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期71-76,共6页
The rodent running-wheel recording apparatus is a reliable approach for studying cir-cadian rhythm.This study demonstrated how to construct a simple and intelligent running-wheel recording system.The running wheel was... The rodent running-wheel recording apparatus is a reliable approach for studying cir-cadian rhythm.This study demonstrated how to construct a simple and intelligent running-wheel recording system.The running wheel was attached to the cage's base,whereas the Hall sensor was attached to the cage's cover.Then,the RJ25 adaptor relayed the running signal to the main control board.Finally,the main control board was connected to the USB port of the computer with the USB connection.Data were collected using the online-accessible,self-created software Magturning.Through Magturning,generated data were saved and exported in real time.Afterward,the device was validated by collecting data on the locomotor activities of mice under dif-ferent light conditions.In conclusion,this new device can record circadian activity of rodents.Our device is appropriate for interdisciplinary investigations related to biological clock research. 展开更多
关键词 biological clock circadian rhythm intelligent equipment locomotor activity running wheel
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Capsaicin alleviates the hepatic clock gene disruption and gut microbiota dysbiosis in circadian rhythm disorder mouse model
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作者 Bolin Lin Chi-Tang Ho +2 位作者 Yawen Wang Jie Xiao Muwen Lu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2947-2958,共12页
As the body’s internal clock,the circadian rhythm regulates the energy expenditure,appetite,and sleep.There exists a close relationship between the host circadian rhythm and gut microbiota.In this work,a circadian di... As the body’s internal clock,the circadian rhythm regulates the energy expenditure,appetite,and sleep.There exists a close relationship between the host circadian rhythm and gut microbiota.In this work,a circadian disorder mouse model induced by constant darkness(CD)was constructed to investigate the regulating effects of capsaicin(CAP)on disturbances of metabolism homeostasis and gut microbiota in the respect of circadian rhythm-related mechanisms.Our results indicated that CAP reduced weight gain induced by circadian rhythm disorder in mice by inhibiting fat accumulation in liver and adipose tissue.The rhythmic expressions of circadian clock genes and lipid-metabolism related genes in liver were also recovered by CAP.Microbial study using 16S rRNA sequencing revealed that CAP modulated the gut microbiota richness,diversity and composition,and restored diurnal oscillations of gut microbes at the phylum and family level.These results indicated that CAP could alleviate CD-induced hepatic clock gene disruption and gut microbiota dysbiosis in mice,providing theoretical basis for CAP to be used as a muti-functional ingredient with great healthpromoting effects. 展开更多
关键词 CAPSAICIN Circadian rhythm Hepatic clock gene Gut microbiota Lipid dysregulation
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Proposal for a realtime Einstein-synchronization-defined satellite virtual clock
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作者 严晨皓 汤雪逸 +4 位作者 王时光 孟李皎悦 孙海媛 何奕彬 王力军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期268-276,共9页
Realization of high performance satellite onboard clock is vital for various positioning, navigation, and timing applications. For further improvement of the synchronization-based satellite time and frequency referenc... Realization of high performance satellite onboard clock is vital for various positioning, navigation, and timing applications. For further improvement of the synchronization-based satellite time and frequency references, we propose a geosynchronous(GEO) satellite virtual clock concept based on ground–satellite synchronization and present a beacon transponder structure for its implementation(scheduled for launch in 2025), which does not require atomic clocks to be mounted on the satellite. Its high performance relies only on minor modifications to the existing transponder structure of GEO satellites. We carefully model the carrier phase link and analyze the factors causing link asymmetry within the special relativity. Considering that performance of such synchronization-based satellite clocks is primarily limited by the link's random phase noise, which cannot be adequately modeled, we design a closed-loop experiment based on commercial GEO satellites for pre-evaluation. This experiment aims at extracting the zero-means random part of the ground-satellite Ku-band carrier phase via a feedback loop. Ultimately, we obtain a 1σ value of 0.633 ps(two-way link), following the Gaussian distribution. From this result, we conclude that the proposed real-time Einstein-synchronization-defined satellite virtual clock can achieve picosecond-level replication of onboard time and frequency. 展开更多
关键词 Einstein synchronization satellite virtual clock geosynchronous satellite carrier phase
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