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基于SMR-RCNN网络的隧道衬砌缺陷智能识别研究
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作者 徐秋朗 罗伟斌 +2 位作者 刘斌 李涛 朱培民 《工程地球物理学报》 2024年第4期541-554,共14页
脱空和不密实是隧道衬砌最常见的两种病害。在这两种病害长期作用下会导致隧道出现破裂、渗漏水、钢筋锈蚀,最终造成隧道塌方等问题,严重威胁行车安全。采用探地雷达对隧道进行无损探测是发现这些病害或缺陷的常见方式,但大量雷达数据... 脱空和不密实是隧道衬砌最常见的两种病害。在这两种病害长期作用下会导致隧道出现破裂、渗漏水、钢筋锈蚀,最终造成隧道塌方等问题,严重威胁行车安全。采用探地雷达对隧道进行无损探测是发现这些病害或缺陷的常见方式,但大量雷达数据的人工识别存在着工作量大、效率低、强烈依赖人员的专业素养等问题。本文提出一种基于深度学习的隧道衬砌缺陷的自动检测方法——自监督多尺度池化区域卷积神经网络方法(Self-monitoring Multi-scale ROI Align Region Convolutional Neural Network,SMR-RCNN),以提高缺陷识别的效率,并减少主观因素的影响。在雷达探测隧道衬砌的实践中,数据量巨大,但缺陷样本却很少,这对训练神经网络是一个相当大的挑战。为此,设计了一种数据增强的方法来增加缺陷的样本数量,且使用一种自监督对比学习的网络模型来提取雷达数据的特征,然后将其迁移到改进后的Faster-RCNN网络模型中;最后,使用有标签的样本对改进的Faster-RCNN网络进行细调训练。实验结果表明,相较于传统的Faster-RCNN方法,本文提出的算法增强了神经网络对脱空和不密实两类缺陷的自动识别能力,在检测精度上得到了显著提高,mAP值提升了12%。 展开更多
关键词 隧道衬砌 缺陷特征 smr-RCNN 对比学习 Faster-RCNN
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Effect of Wearing a Maxillofacial Prosthesis on Masticatory Rhythm Improvement in Mandibulectomy Patients
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作者 Xuewei Han Mihoko Haraguchi +2 位作者 Yuka I. Sumita Marwa Ahmed Aboelez Noriyuki Wakabayashi 《Health》 2024年第7期717-729,共13页
Background: Recording jaw movement rhythms in patients with jaw defects is challenging using conventional tracking devices. However, masticatory rhythm is crucial for masticatory performance and nutritional intake. Th... Background: Recording jaw movement rhythms in patients with jaw defects is challenging using conventional tracking devices. However, masticatory rhythm is crucial for masticatory performance and nutritional intake. This study aimed to explore the impact of using a maxillofacial prosthesis to restore masticatory rhythm in mandibulectomy patients with a novel wearable device. Methods: Twelve patients who underwent mandibulectomy and were rehabilitated with maxillofacial prosthesis were recruited. Chewing rate, cycle durations, coefficient of variation of cycle durations (CV), changing times of skin morphology on the back of the ear pinna area (SM), and masticatory performance were measured during gum chewing without and with a denture using a wearable jaw movement rhythm tracking device. A paired t-test and the Pearson correlation coefficient were used for statistical analysis. Results: The chewing rate increased by 8.6 cycles/min with dentures (P P = 0.01). The CV and SM decreased with dentures (P = 0.004 and P = 0.01, respectively). Significant correlations were found between the CV and SM without dentures (P = 0.004). Conclusion: 1. Wearing maxillofacial prostheses can improve masticatory rhythm in patients who undergo mandibulectomy with Eichner B2 occlusal supports. 2. The wearable device is available for measuring masticatory rhythm in patients with jaw defects in clinics. 3. Changing times of the skin morphology on the back of the ear pinna indicate jaw movement stability through a simpler process than the coefficient of variation of cycle durations. 展开更多
关键词 Masticatory rhythm Jaw Movement rhythm Tracking Device Maxillofacial Prosthesis Head and Neck Tumor Mandibulectomy
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Probiotics administration alleviates cognitive impairment and circadian rhythm disturbance induced by sleep deprivation
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作者 Peijun Tian Yunfei Hou +6 位作者 Zheng Wang Jiaona Jiang Xin Qian Zhihao Qu Jianxin Zhao Gang Wang Wei Chen 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1951-1961,共11页
Gut microbiome is indispensable for maintaining normal brain function.Specifically,gut microbiota plays a causal role in sleep deprivation(SD)-induced cognitive impairment.In this study,neurobehavioral effects of the ... Gut microbiome is indispensable for maintaining normal brain function.Specifically,gut microbiota plays a causal role in sleep deprivation(SD)-induced cognitive impairment.In this study,neurobehavioral effects of the Bifidobacterium breve strain(CCFM1025)were assessed in sleep-deprived mice.CCFM1025 improved the body weight and food and water intake of the mice.It also alleviated SD-induced cognitive behavioural abnormalities(in the novel object recognition test),but did not show beneficial effects on mood-and spatial memory-related behaviours.CCFM1025 significantly altered the gut microbial composition and genome function.Key microbial metabolites that may regulate sleep function were also identified,such as isovaleric acid andγ-aminobutyric acid in the gut and purine metabolites in the serum.Those metabolites may participate in gutbrain communication by acting on the striatal melatonin system,for example to increase melatonin levels,and by regulating the expression of circadian clock genes such as those encoding the adenosine A2A receptor and period circadian regulator 1.Collectively,administration of probiotics alleviated cognitive impairment and circadian rhythm disturbance induced by SD via modulation of gut microbiome and its metabolites.These findings may help guide the treatment of insomnia or other sleep disorders via dietary strategies. 展开更多
关键词 BIFIDOBACTERIUM SLEEP Circadian rhythm PURINE Gut microbiome
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Autophagy and circadian rhythms:interactions and clinical implications
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作者 TIANKAI DI ZHIFEI ZHOU +2 位作者 FEN LIU YUJIANG CHEN LULU WANG 《BIOCELL》 SCIE 2024年第1期33-45,共13页
Autophagy is a widespread biological process that controls cellular growth,survival,development,and death.Circadian rhythm is a recurring reaction of living organisms and behaviors to variations in surrounding brightn... Autophagy is a widespread biological process that controls cellular growth,survival,development,and death.Circadian rhythm is a recurring reaction of living organisms and behaviors to variations in surrounding brightness and obscurity.Most of the fundamental physiological processes in mammals,such as the sleep-wake pattern and the rhythm of nutrition and energy metabolism,are governed by circadian rhythms.Research has indicated that autophagy exhibits a specific circadian pattern in both normal and abnormal conditions.Autophagy can modulate circadian rhythms by breaking down proteins that regulate the circadian clock.The potential regulatory connection between the two has been a popular subject of clinical and fundamental research.Understanding the interaction between circadian rhythm and autophagy could potentially lead to the development of novel approaches for disease treatment in the future.The present analysis presented a summary of the molecular processes implicated in the interplay between autophagy and circadian rhythm,as well as the pathological importance of the disrupted regulatory association between these two phenomena. 展开更多
关键词 AUTOPHAGY Circadian rhythms MECHANISM APPLICATION
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Circadian rhythm disruption and retinal dysfunction:a bidirectional link in Alzheimer’s disease?
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作者 Laura Carrero DesireéAntequera +1 位作者 Cristina Municio Eva Carro 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1967-1972,共6页
Dysfunction in circadian rhythms is a common occurrence in patients with Alzheimer’s disease.A predominant function of the retina is circadian synchronization,carrying information to the brain through the retinohypot... Dysfunction in circadian rhythms is a common occurrence in patients with Alzheimer’s disease.A predominant function of the retina is circadian synchronization,carrying information to the brain through the retinohypothalamic tract,which projects to the suprachiasmatic nucleus.Notably,Alzheimer’s disease hallmarks,including amyloid-β,are present in the retinas of Alzheimer’s disease patients,followed/associated by structural and functional disturbances.However,the mechanistic link between circadian dysfunction and the pathological changes affecting the retina in Alzheimer’s disease is not fully understood,although some studies point to the possibility that retinal dysfunction could be considered an early pathological process that directly modulates the circadian rhythm. 展开更多
关键词 Alzheimer’s disease AMYLOID circadian rhythm NEURODEGENERATION RETINA
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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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Interaction between adolescent sleep rhythms and gender in an obese population
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作者 Nan-Nan Wu Guo-Li Yan +3 位作者 Hong-Yu Zhang Ling Sun Min Hou Guang-Ming Xu 《World Journal of Clinical Cases》 SCIE 2024年第1期86-94,共9页
BACKGROUND The obesity rate of adolescents is gradually increasing,which seriously affects their mental health,and sleep plays an important role in adolescent obesity.AIM To investigate the relationship between sleep ... BACKGROUND The obesity rate of adolescents is gradually increasing,which seriously affects their mental health,and sleep plays an important role in adolescent obesity.AIM To investigate the relationship between sleep rhythm and obesity among adolescents and further explores the interactive effect of sleep rhythm and gender on adolescent obesity,providing a theoretical basis for developing interventions for adolescent obesity.METHODS Research data source Tianjin Mental Health Promotion Program for Students.From April to June 2022,this study selected 14201 students from 13 middle schools in a certain district of Tianjin as the research subject using the convenient cluster sampling method.Among these students,13374 accepted and completed the survey,with an effective rate of 94.2%.The demographic data and basic information of adolescents,such as height and weight,were collected through a general situation questionnaire.The sleep rhythm of adolescents was evaluated using the reduced version of the morningness-eveningness questionnaire.RESULTS A total of 13374 participants(6629 females,accounting for 49.56%;the average age is 15.21±1.433 years)were analyzed.Among them,the survey showed that 2942 adolescent were obesity,accounting for 22%and 2104 adolescent were overweight,accounting for 15.7%.Among them,1692 male adolescents are obese,with an obesity rate of 25.1%,higher than 18.9%of female adolescents.There is a statistically significant difference between the three groups(χ2=231.522,P<0.000).The obesity group has the smallest age(14.94±1.442 years),and there is a statistical difference in age among the three groups(F=69.996,P<0.000).Obesity rates are higher among individuals who are not-only-child,have residential experience within six months,have family economic poverty,and have evening-type sleep(P<0.05).Logistic regression analysis shows a correlation between sleep rhythm and adolescent obesity.Evening-type sleep rhythm can increase the risk of obesity in male adolescents[1.250(1.067-1.468)],but the effect on female obesity is not remarkable.Further logistic regression analysis in the overall population demonstrates that the interaction between evening-type sleep rhythm and the male gender poses a risk of adolescent obesity[1.122(1.043-1.208)].CONCLUSION Among adolescents,the incidence of obesity in males is higher than in females.Evening-type sleep rhythm plays an important role in male obesity but has no significant effect on female obesity.Progressive analysis suggests an interactive effect of sleep rhythm and gender on adolescent obesity,and the combination of evening-type sleep and the male gender promotes the development of adolescent obesity.In formulating precautions against adolescent obesity,obesity in male adolescents with evening-type sleep should be a critical concern. 展开更多
关键词 ADOLESCENT OBESITY Sleep rhythm GENDER INTERACTION
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The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model
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作者 Ruonan Yan Chi-Tang Ho +3 位作者 Yanan Liu Shengnan Zhan Zufang Wu Xin Zhang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期748-764,共17页
The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)impro... The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state imbalance.After fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic cells.Our results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health. 展开更多
关键词 Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism
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Unraveling links between aging,circadian rhythm and cancer:Insights from evidence-based analysis
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作者 Dechao Feng Yuhan Xiao +10 位作者 Jie Wang Ruicheng Wu Zhouting Tuo Koo Han Yoo Wuran Wei Dilinaer Wusiman Zhipeng Wang Dengxiong Li Yubo Yang William C.Cho Mang Ke 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第3期341-350,共10页
Aging and circadian rhythms have been connected for decades,but their molecular interaction has remained unknown,especially for cancers.In this situation,we summarized the current research actuality and problems in th... Aging and circadian rhythms have been connected for decades,but their molecular interaction has remained unknown,especially for cancers.In this situation,we summarized the current research actuality and problems in this field using the bibliometric analysis.Publications in the PubMed and Web of Science databases were retrieved.Overall,there is a rising trend in the publication volume regarding aging and circadian rhythms in the field of cancer.Researchers from USA,Germany,Italy,China and England have greater studies than others.Top three publication institutions are University of California System,UDICE-French Research Universities and University of Texas System.Current research hotspots include oxidative stress,breast cancer,melatonin,cell cycle,calorie restriction,prostate cancer and NF-κB.In conclusion,results generated by bibliometric analysis indicate that many approaches involve in the complex interactions between aging and circadian rhythm in cancer.These established and emerging research directions guide our exploration of the regulatory mechanisms of aging and circadian rhythms in cancer and provide a reference for developing new research avenues. 展开更多
关键词 AGING circadian rhythm human cancer bibliometric analysis oxidative stress
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Corneal and intraocular pressure changes associated to the circadian rhythms:a narrative review
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作者 Laura Barberán-Bernardos MiguelÁngel Ariza-Gracia David P Piñero 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第10期1921-1928,共8页
AIM:To synthesize the current body of research regarding the diurnal variations in intraocular pressure(IOP)and corneal biomechanical and morphological parameters,highlighting their significance in various eye conditi... AIM:To synthesize the current body of research regarding the diurnal variations in intraocular pressure(IOP)and corneal biomechanical and morphological parameters,highlighting their significance in various eye conditions.METHODS:A comprehensive review of studies on the diurnal variations of IOP and corneal parameters was conducted.Tonometry findings from various studies were assessed,including the Goldmann applanation tonometry(GAT)and non-contact tonometers.Data on the variations in central corneal thickness(CCT),corneal curvature,and corneal biomechanics measured by the Ocular Response Analyzer system across different population groups was extracted and analyzed.RESULTS:In both healthy subjects and those with Fuchs dystrophy,IOP and CCT demonstrate marked diurnal declines.GAT remains the gold standard for tonometry,with the highest reliability.However,its measurements are influenced by CCT.Keratoconus patients and those with pseudoexfoliation showed significant diurnal variations in IOP.The biomechanical parameters,especially corneal hysteresis(CH)and the corneal resistance factor(CRF),largely remain stable throughout the day for most of eye conditions,with some exceptions.Notably,the corneal morphology diurnal variation,particularly curvature,yielded mixed conclusions across studies.CONCLUSION:Circadian rhythms significantly influence various corneal parameters,most notably IOP and CCT.Further studies should emphasize standardized approaches larger sample sizes,and delve deeper into less-explored areas,such as the effects of orthokeratology lenses on diurnal biomechanical shifts. 展开更多
关键词 circadian rhythms intraocular pressure corneal thickness corneal biomechanics corneal curvature
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The Regulatory Role and Mechanism of Circadian Rhythm in Hemoglobin Co-cultured Neurovascular Unit
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作者 Fang Xue Wenchao Chen +4 位作者 Xia Lian Guanghui He Jingyuan Tian Yinghong Liu Gaiqing Wang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第7期726-738,共13页
Objective Intracranial hemorrhage(ICH),the second most common subtype of stroke,exacerbates the disruption of the blood-brain barrier(BBB),leading to vasogenic edema,plasma protein extravasation,and infiltration of ne... Objective Intracranial hemorrhage(ICH),the second most common subtype of stroke,exacerbates the disruption of the blood-brain barrier(BBB),leading to vasogenic edema,plasma protein extravasation,and infiltration of neurotoxic substances.The clearance capacity of the brain plays a crucial role in maintaining BBB homeostasis and facilitating patient recovery after hemorrhage.This study aimed to investigate the effect of circadian rhythms on BBB function,neuronal damage,and clearance capabilities.Methods The transwell model and hemoglobin were co-cultured to simulate the BBB environment after ICH.After intervention with different light groups,neuronal apoptosis was determined,glial phagocytosis was analyzed,the expression of endogenous clearing-related proteins aquaporin 4(AQP4)and low-density lipoprotein receptor-related protein 1(LRP1)was detected by western blotting and immunofluorescence dual standard method,and the expression of the tight junction protein occludin and melatonin receptor 1A(MTNR1A)was quantitatively analyzed.Results Circadian rhythms play a key role in maintaining the integrity of the BBB,reducing oxidative stress-induced neuronal damage,and improving microglial phagocytosis.Meanwhile,the expression of occludin and MTNR1A in neurovascular unit(NVU)co-cultured with hemoglobin improved the expression of AQP4 and LRP1,the key proteins in the NVU's endogenous brain clearance system.Conclusion Circadian rhythm(alternating black and white light)protects the NVU BBB function after ICH,promotes the expression of proteins related to the clearance of the hematoma,provides new evidence for the clinical treatment of patients recovering from ICH,and improves the circadian rhythm to promote brain metabolism and hematoma clearance. 展开更多
关键词 Blood-brain barrier Circadian rhythm Neurovascular unit Melatonin receptor 1A AQUAPORIN-4
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NEA的小型模块化反应堆(SMR)战略
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《辐射防护》 CAS CSCD 北大核心 2024年第1期49-49,共1页
小型模块化反应堆(SMR)在功率输出和物理尺寸方面都比传统的千兆瓦级核反应堆小。通常,SMR是功率输出小于300兆瓦电力(MWe)的核反应堆,有些小至1~10兆瓦。SMR专为模块化制造、生产、方便移动性和可扩展部署而设计。SMR利用核裂变反应产... 小型模块化反应堆(SMR)在功率输出和物理尺寸方面都比传统的千兆瓦级核反应堆小。通常,SMR是功率输出小于300兆瓦电力(MWe)的核反应堆,有些小至1~10兆瓦。SMR专为模块化制造、生产、方便移动性和可扩展部署而设计。SMR利用核裂变反应产生可以直接使用的热量,或用于发电。一些小型模块堆基于目前部署的技术,而另一些则基于所谓的“第四代”和先进的反应堆概念。 展开更多
关键词 核反应堆 模块化制造 物理尺寸 核裂变 兆瓦级 smr 移动性 功率输出
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Circadian rhythm disruption and endocrine-related tumors
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作者 Christos Savvidis Efthymia Kallistrou +7 位作者 Eleni Kouroglou Sofia Dionysopoulou Georgios Gavriiloglou Dimitra Ragia Vasiliki Tsiama Stella Proikaki Konstantinos Belis Ioannis Ilias 《World Journal of Clinical Oncology》 2024年第7期818-834,共17页
This review delved into the intricate relationship between circadian clocks and physiological processes,emphasizing their critical role in maintaining homeo-stasis.Orchestrated by interlocked clock genes,the circadian... This review delved into the intricate relationship between circadian clocks and physiological processes,emphasizing their critical role in maintaining homeo-stasis.Orchestrated by interlocked clock genes,the circadian timekeeping system regulates fundamental processes like the sleep-wake cycle,energy metabolism,immune function,and cell proliferation.The central oscillator in the hypothalamic suprachiasmatic nucleus synchronizes with light-dark cycles,while peripheral tissue clocks are influenced by cues such as feeding times.Circadian disruption,linked to modern lifestyle factors like night shift work,correlates with adverse health outcomes,including metabolic syndrome,cardiovascular diseases,infec-tions,and cancer.We explored the molecular mechanisms of circadian clock genes and their impact on metabolic disorders and cancer pathogenesis.Specific associ-ations between circadian disruption and endocrine tumors,spanning breast,ovarian,testicular,prostate,thyroid,pituitary,and adrenal gland cancers,are highlighted.Shift work is associated with increased breast cancer risk,with PER genes influencing tumor progression and drug resistance.CLOCK gene expression correlates with cisplatin resistance in ovarian cancer,while factors like aging and intermittent fasting affect prostate cancer.Our review underscored the intricate interplay between circadian rhythms and cancer,involving the regulation of the cell cycle,DNA repair,metabolism,immune function,and the tumor microenvir-onment.We advocated for integrating biological timing into clinical consider-ations for personalized healthcare,proposing that understanding these connec-tions could lead to novel therapeutic approaches.Evidence supports circadian rhythm-focused therapies,particularly chronotherapy,for treating endocrine tumors.Our review called for further research to uncover detailed connections between circadian clocks and cancer,providing essential insights for targeted treatments.We emphasized the importance of public health interventions to mitigate lifestyle-related circadian disruptions and underscored the critical role of circadian rhythms in disease mechanisms and therapeutic interventions. 展开更多
关键词 Circadian rhythm Circadian disruption Shift work CLOCK gene CANCER Endocrine tumors CHRONOTHERAPY
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韩公布小堆设计i-SMR并与印尼和约旦签署合作协议
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作者 伍浩松 张焰 《国外核新闻》 2024年第1期8-8,共1页
【韩国经济日报网站2023年12月4日报道】2023年12月4日,在第28次联合国气候变化大会期间,韩国水电核电公司(KHNP)首次公布模块化小型压水堆设计i-SMR,并分别与印尼和约旦相关企业或机构签署协议,将联合研究部署这种小堆的可行性。i-SMR... 【韩国经济日报网站2023年12月4日报道】2023年12月4日,在第28次联合国气候变化大会期间,韩国水电核电公司(KHNP)首次公布模块化小型压水堆设计i-SMR,并分别与印尼和约旦相关企业或机构签署协议,将联合研究部署这种小堆的可行性。i-SMR是一种一体化压水堆,电功率17万千瓦。韩水电核电计划于2025年完成i-SMR标准设计,并于2028年获得监管机构颁发的设计合格证。 展开更多
关键词 核电公司 标准设计 smr 监管机构 合格证 约旦 水电 印尼
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英启动美小堆SMR-300通用设计评审
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作者 伍浩松 孟雨晨 《国外核新闻》 2024年第1期8-8,共1页
【英国核监管办公室网站2023年12月7日报道】英国核监管办公室(ONR)、环境署和威尔士自然资源部近日已根据英国能源安全和净零排放部要求,启动对美国霍尔台克国际公司(Holtec International)模块化小型压水堆设计SMR-300通用设计评审(G... 【英国核监管办公室网站2023年12月7日报道】英国核监管办公室(ONR)、环境署和威尔士自然资源部近日已根据英国能源安全和净零排放部要求,启动对美国霍尔台克国际公司(Holtec International)模块化小型压水堆设计SMR-300通用设计评审(GDA)程序。在GDA评审过程中,英国监管机构将根据“通用厂址”特征评价反应堆设计的环境影响。 展开更多
关键词 评审过程 设计评审 环境署 特征评价 自然资源部 能源安全 smr 监管机构
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美小堆SMR-300通过英第一阶段GDA评审
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作者 张焰 伍浩松 《国外核新闻》 2024年第9期10-10,共1页
【英国核监管办公室网站2024年8月1日报道】英国核监管办公室(ONR)、英国环境署和威尔士自然资源部2024年8月1日宣布,已完成对美国霍尔台克国际公司(Holtec International)模块化小型压水堆设计SMR-300第一阶段通用设计评审(GDA),即将... 【英国核监管办公室网站2024年8月1日报道】英国核监管办公室(ONR)、英国环境署和威尔士自然资源部2024年8月1日宣布,已完成对美国霍尔台克国际公司(Holtec International)模块化小型压水堆设计SMR-300第一阶段通用设计评审(GDA),即将启动可能持续14个月的第二阶段评审。GDA是一个非强制性的、最多分为三个阶段的灵活程序。在评审过程中,英国监管机构将根据“通用厂址”特征评价反应堆设计的环境影响。 展开更多
关键词 评审过程 设计评审 环境署 特征评价 自然资源部 smr 监管机构 环境影响
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Adjusting phosphate feeding regimen according to daily rhythm increases eggshell quality via enhancing medullary bone remodeling in laying hens 被引量:1
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作者 Jiakun Yan Jiajie Wang +7 位作者 Jie Chen Hao Shi Xujie Liao Chong Pan Yanli Liu Xin Yang Zhouzheng Ren Xiaojun Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1274-1286,共13页
Background Body phosphorus metabolism exhibits a circadian rhythm over the 24-h daily cycle.The egg laying behavior makes laying hens a very special model for investigating phosphorus circadian rhythms.There is lack o... Background Body phosphorus metabolism exhibits a circadian rhythm over the 24-h daily cycle.The egg laying behavior makes laying hens a very special model for investigating phosphorus circadian rhythms.There is lack of information about the impact of adjusting phosphate feeding regimen according to daily rhythm on the phosphorus homeostasis and bone remodeling of laying hens.Methods and results Two experiments were conducted.In Exp.1,Hy-Line Brown laying hens(n=45)were sampled according the oviposition cycle(at 0,6,12,and 18 h post-oviposition,and at the next oviposition,respectively;n=9 at each time point).Diurnal rhythms of body calcium/phosphorus ingestions and excretions,serum calcium/phosphorus levels,oviduct uterus calcium transporter expressions,and medullary bone(MB)remodeling were illustrated.In Exp.2,two diets with different phosphorus levels(0.32%and 0.14%non-phytate phosphorus(NPP),respectively)were alternately presented to the laying hens.Briefly,four phosphorus feeding regimens in total(each included 6 replicates of 5 hens):(1)fed 0.32%NPP at both 09:00 and 17:00;(2)fed 0.32%NPP at 09:00 and 0.14%NPP at 17:00;(3)fed 0.14%NPP at 09:00 and 0.32%NPP at 17:00;(4)fed 0.14%NPP at both 09:00 and 17:00.As a result,the regimen fed 0.14%NPP at 09:00 and 0.32%NPP at 17:00,which was designed to strengthen intrinsic phosphate circadian rhythms according to the findings in Exp.1,enhanced(P<0.05)MB remodeling(indicated by histological images,serum markers and bone mineralization gene expressions),elevated(P<0.05)oviduct uterus calcium transportation(indicated by transient receptor potential vanilloid 6 protein expression),and subsequently increased(P<0.05)eggshell thickness,eggshell strength,egg specific gravity and eggshell index in laying hens.Conclusions These results underscore the importance of manipulating the sequence of daily phosphorus ingestion,instead of simply controlling dietary phosphate concentrations,in modifying the bone remodeling process.Body phosphorus rhythms will need to be maintained during the daily eggshell calcification cycle. 展开更多
关键词 Body phosphorus rhythm Bone remodeling Eggshell formation Laying hen Phosphorus feeding regimen
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Circadian Rhythm of Childbirths and Maternal and Neonatal Prognosis at the YaoundéCentral Hospital
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作者 Florent Ymele Fouelifack Jufo Donkeng +5 位作者 William Takang Edmond Mesumbe Loic Dongmo Fouelifa Mosman Anyimbi Ofeh Jackson Ndenkeh Jeanne Hortence Fouedjio 《Advances in Reproductive Sciences》 CAS 2023年第1期11-22,共12页
Background: The circadian variation of childbirths has been described by several authors around the globe. De Graaf showed that hospital childbirths at night were associated with increased perinatal mortality and adve... Background: The circadian variation of childbirths has been described by several authors around the globe. De Graaf showed that hospital childbirths at night were associated with increased perinatal mortality and adverse perinatal outcome. To improve obstetric care, we carried out this study to evaluate the circadian rhythm of childbirths and to assess the outcome following variations in the time of childbirths during the day. Methods: It was a cross-sectional descriptive study at the Yaoundé Central Hospital (YCH), over a two years period. We collected data from files of women who delivered from the 1st of January 2017 to 31st December 2018. We included files of women who delivered at least at 28 weeks of pregnancy. We excluded files of those who delivered by elective caesarean section, those whose hour of delivery was not noted and those who delivered before reaching the hospital. Sociodemographic, obstetrical characteristics, and immediate prognosis were recorded. Data were entered into excel, then analysed with SPSS v23 software. Tools used to appreciate our results were means, median, number, percentage, P, and OR with its 95% confidence interval. The difference in p is significant if p is less than 5%. Results: We analyzed 6041 files bearing the time of birth. Childbirths took place at all hours of the day, but the times of the day where the highest numbers of births were recorded were 10, 11, 12, 13 (that’s 1pm), 14 (that’s 2 pm), 15 (that’s 3 pm), 16 (that’s 4 pm), 17 (that’s 5 pm) and 23 (that’s 11 pm) hours, with respectively 224 (3.7%), 277 (4.6%), 256 (4.2%), 265 (4.4%), 207 (3.4%), 255 (4.2%), 228 (3.8%), 216 (3.6%) and 226 (3.7%) births. The peak of births was at 11 am while the time of day where the lowest number of births was recorded was 6 pm, with 175 (2.9%) births. The mean age of participants was 27.34 ± 6.03 years with extremes of 13 and 49, with 87.6% between 20 to 39 years. Sociodemographic characteristics of participants, prematurity and bleeding during delivery, had no dependence on the time of delivery. Perineal tear, duration of observation, Apgar score of the newborn, birthweight, delivery mode, health personnel who performed the delivery, and episiotomyseemed to be influenced by the time of delivery. Daily shifts were not independently associated with the poor Apgar score (0 - 6) at 5 mins, when adjusted for all other factors (p = 0.109). Conclusion: Childbirths were more frequent between 10 am and 5 pm. The period where episiotomy was most performed is the same as when there was macrosomia childbirth. Tears of the perineum are more frequent between 2 pm and 10 pm. There was no independent association between Daily shifts and poor Apgar score. The poor APGAR score would be more related to low birth weight. 展开更多
关键词 Circadian rhythm CHILDBIRTH MATERNAL NEONATAL PROGNOSIS
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Potential Power of the Pyramidal Structure VII: Effects of Pyramid Power and Bio-Entanglement on the Circadian Rhythm of Biosensors
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作者 Osamu Takagi Masamichi Sakamoto +1 位作者 Kimiko Kawano Mikio Yamamoto 《Natural Science》 CAS 2023年第1期19-38,共20页
We have demonstrated the existence of a pyramid power and have revealed its characteristics by strictly scientific experiments using biosensors. We also revealed the existence of a Bio-Entanglement, an entangled relat... We have demonstrated the existence of a pyramid power and have revealed its characteristics by strictly scientific experiments using biosensors. We also revealed the existence of a Bio-Entanglement, an entangled relationship between biosensors. A parallel study of biosensors (edible cucumber slices) had also been conducted, and we found that the circadian rhythm of gas concentrations emitted from biosensors changes seasonally. The pyramid power and Bio-Entanglement did not change the number of cycles in the periodic approximation curve representing circadian rhythm. Therefore, in this paper we analyzed the influence of the pyramid power and Bio-Entanglement, i.e., their influence on the phase, amplitude, and correlation coefficient of the periodic approximation curve representing the circadian rhythm of emitted gas concentrations. The main results are as follows. 1) The pyramid power shifted the phase of the periodic approximation curve representing the circadian rhythm by 43 minutes. 2) The amplitude of the periodic approximation curve changed with the pyramid power and the Bio-Entanglement. The effect on the lower and upper sections of the biosensors stacked in two layers was different, with a tendency to increase the amplitude of the lower layer and decrease the amplitude of the upper layer. 3) The pyramid power and the Bio-Entanglement affected the correlation coefficient between gas concentration and the periodic approximation curve representing the circadian rhythm of gas concentration. The effect on the lower and upper layers of the biosensors was different, with a tendency for the lower layer correlation coefficient to be larger and the upper layer correlation coefficient to be smaller. Previously we demonstrated that the pyramid power and the Bio-Entanglement affect the ratio of gas concentration, i.e., psi index Ψ. In this paper we demonstrate for the first time that the pyramid power and the Bio-Entanglement affect time, i.e., phase difference. 展开更多
关键词 PYRAMID BIOSENSOR Cucumis sativus Circadian rhythm ENTANGLEMENT Gas SEASON
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Feasibility to Convert the NuScale SMR from UO2 to a Mixed (U, Th)O2 Core: A Parametric Study of Fuel Element—Seed-Blanket Concept
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作者 Giovani Laranjo de Stefani Diego Manoel Enedino Gonçalves +2 位作者 Cesar Raitz Marcelo V. da Silva Caio Július César Miranda Rodrigues da Cunha 《World Journal of Nuclear Science and Technology》 CAS 2023年第2期11-28,共18页
Delays in the construction of nuclear reactors due to licensing issues have been a problem across the world, affecting projects in Finland, France, and the United States. Small Modular Reactors (SMRs) emerge as a tran... Delays in the construction of nuclear reactors due to licensing issues have been a problem across the world, affecting projects in Finland, France, and the United States. Small Modular Reactors (SMRs) emerge as a transition between Generations III+ and IV in order to make nuclear energy more competitive with other energy sources, including renewables. In this study, the SMR NuScale, one of the most promising projects today, is investigated for its conversion into a U-233-producing reactor through the Radkowsky seed-blanket fuel element concept, applied in the Shippingport reactor, in a parametric study. Initially, a validation of the reference reactor (NuScale) was carried out with data from technical documents and papers, thus demonstrating the agreement of the computational model carried out with the SERPENT code. Then, a parametric study is carried out to define the area of the seed and blanket region, proportions of enrichment and pitch length. Finally, a comparison is made between the production of U-233, TRU reduction, burn-up extension and neutronic and thermohydraulic safety parameters. This study demonstrates an improvement in the conversion factor and a considerable reduction in the production of TRU, in addition to the production of U-233 with a low proportion of other uranium isotopes that can lead to the beginning of the thorium cycle with already consolidated technologies. 展开更多
关键词 Thorium smr Seed-Blanket NuScale
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