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Striving for the development of biology——The celebration of Biomagnelism formally changed into Progress in Modem Biomedicine 被引量:2
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作者 Editorial Department of Progress in Modern Biomedicine 《现代生物医学进展》 CAS 2006年第6期F0002-F0002,共1页
关键词 Striving for the development of biology The celebration of Biomagnelism formally changed into Progress in Modem Biomedicine
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Both ABO and MN blood groups have changed after Allo-PBSCT
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《中国输血杂志》 CAS CSCD 2001年第S1期379-,共1页
关键词 ABO Both ABO and MN blood groups have changed after Allo-PBSCT
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A CHANGED FACE OF GUANGZHOU TRADE FAIR
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《大经贸》 北大核心 1996年第11期91-91,共1页
FAMOUS-BRAND PRODUCTS ARE WARMLY WELCOMEUPGRADING TECHNOLOGIES ARE HIGHLY CHERISHEDEXQUISITE FINE-ART PRODUCTS RECEIVE SPECIAL ATTENTION.
关键词 HIGH ARE A changed FACE OF GUANGZHOU TRADE FAIR
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Words That Changed a Life
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作者 Bob Greene 方陵生 《语言教育》 1999年第7期24-26,共3页
“Are you too stupid to do anything right?”These words—said by a woman to a little boy who was evidently her son—were spoken because he had walked away from her.Andthey were said at a volume high enough that all th... “Are you too stupid to do anything right?”These words—said by a woman to a little boy who was evidently her son—were spoken because he had walked away from her.Andthey were said at a volume high enough that all the strangersin the vicinity could hear.Chastised,the boy returned quiet-ly to the woman’s side,his eyes downcast.Not a big moment,perhaps.Yet small moments some- 展开更多
关键词 Words That changed a Life
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It was love that changed me
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作者 于莹莹 《疯狂英语(初中天地)》 2002年第47期26-26,共1页
Once I was a conceited girl.I would neveraccept the advice of others.I was never readyto help others.Sometimes when someone wasin trouble,I liked to play a joke on him orher.So many classmates disliked me.My teach-ers... Once I was a conceited girl.I would neveraccept the advice of others.I was never readyto help others.Sometimes when someone wasin trouble,I liked to play a joke on him orher.So many classmates disliked me.My teach-ers often tried to change me,but I wouldn’tlisten. 展开更多
关键词 It was love that changed me
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Non-alcoholic fatty liver disease: What has changed in the treatment since the beginning? 被引量:11
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作者 Bülent Baran Filiz Akyüz 《World Journal of Gastroenterology》 SCIE CAS 2014年第39期14219-14229,共11页
Non-alcoholic fatty liver disease(NAFLD) is an umbrella term to describe the entire spectrum of this common liver disease. In patients with NAFLD, especially those with non-alcoholic steatohepatitis(NASH), most often ... Non-alcoholic fatty liver disease(NAFLD) is an umbrella term to describe the entire spectrum of this common liver disease. In patients with NAFLD, especially those with non-alcoholic steatohepatitis(NASH), most often have one or more components of the metabolic syndrome, but this is not universal. Although most patients with NAFLD share many clinical features, only a subset of patients develops significant liver inflammation and progressive fibrosis. On the other hand, not all patients with NASH exhibit insulin resistance. NASH can be seen in patients who are lean and have no identifiable risk factors. Many clinical studies have tried numerous drugs and alternative medicine, however, investigators have failed to identify a safe and effective therapy for patients with NASH. As summarized, the heterogeneity of pathogenic pathways in individual patients with NASH may warrant the development of an individualized treatment according to the underlying pathogenic pathway. The differentiation of pathogenetic targets may require the development of diagnostic and prognostic biomarkers, and the identification of genetic susceptibilities. At present, evidence-based medicine provides only a few options including life-style modifications targeting weight loss, pioglitazone and vitamin E in non-diabetic patients with biopsy-proven NASH. 展开更多
关键词 Non-alcoholic steatohepatitis PATHOGENESIS INFLAMMATION FIBROSIS Life-style changes Pharmacologic treatment
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Simulation of the mixing process in a straight tube with sudden changed cross-section 被引量:3
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作者 Yangcheng LU Shan Zhu +1 位作者 Kai Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第6期711-718,共8页
In this work, we revised the expression of mixing intensity to describe the mixing output through a cross section in a flow system by considering heterogeneity of flow field, and carefully investigated the mixing proc... In this work, we revised the expression of mixing intensity to describe the mixing output through a cross section in a flow system by considering heterogeneity of flow field, and carefully investigated the mixing process along a straight tube with expanding/contracting cross section by simulation method. The simulation results show that a sudden expansion of cross section has remarkable mixing intensification effect within a limited period(on the sub-second scale) or tube-length(on the millimeter scale), corresponding to the generation of considerable local vortices determined by both the flow capacity and the ratio of cross section change; a sudden contraction of cross section has instantaneous but weak mixing intensification effect; through introducing a local expansion structure with proper length, as the combination of sudden expansion and sudden contraction, their mixing intensification effects could be superposed. Besides, the rationality and importance are experimentally verified to explore the time profile of mixing intensity and carry out the vortex analysis by simulation for enhancing the selectivity of a complicated reaction system. These progresses may lead to more meaningful quantitative description of mixing process in a flow microreactor for some specific chemical processes. 展开更多
关键词 MixingIntensificationSimulationSudden change in cross-sectionVortex
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Prediction of Changed Faces with HSCNN
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作者 Jinho Han 《Computers, Materials & Continua》 SCIE EI 2022年第5期3747-3759,共13页
Convolutional Neural Networks(CNN)have been successfully employed in the field of image classification.However,CNN trained using images from several years ago may be unable to identify how such images have changed ove... Convolutional Neural Networks(CNN)have been successfully employed in the field of image classification.However,CNN trained using images from several years ago may be unable to identify how such images have changed over time.Cross-age face recognition is,therefore,a substantial challenge.Several efforts have been made to resolve facial changes over time utilizing recurrent neural networks(RNN)with CNN.The structure of RNN contains hidden contextual information in a hidden state to transfer a state in the previous step to the next step.This paper proposes a novel model called Hidden State-CNN(HSCNN).This adds to CNN a convolution layer of the hidden state saved as a parameter in the previous step and requires no more computing resources than CNN.The previous CNN-RNN models perform CNN and RNN,separately and then merge the results.Therefore,their systems consume twice the memory resources and CPU time,compared with the HSCNN system,which works the same as CNN only.HSCNN consists of 3 types of models.All models load hidden state ht−1 from parameters of the previous step and save ht as a parameter for the next step.In addition,modelB adds ht−1 to x,which is the previous output.The summation of ht−1 and x is multiplied by weight W.In model-C the convolution layer has two weights:W1 and W2.Training HSCNN with faces of the previous step is for testing faces of the next step in the experiment.That is,HSCNN trained with past facial data is then used to verify future data.It has been found to exhibit 10 percent greater accuracy than traditional CNN with a celeb face database. 展开更多
关键词 CNN-RNN HSCNN hidden state changing faces
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REDEFINING ENSO EPISODES BASED ON CHANGED CLIMATE REFERENCES
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作者 李晓燕 翟盘茂 任福民 《Journal of Tropical Meteorology》 SCIE 2005年第1期97-103,共7页
Through studying changes in ENSO indices relative to change of climate reference from 1961~1990 to 1971~2000, the study generated new standards to define ENSO episodes and their intensities. Then according to the new ... Through studying changes in ENSO indices relative to change of climate reference from 1961~1990 to 1971~2000, the study generated new standards to define ENSO episodes and their intensities. Then according to the new climate references and new index standards, ENSO episodes and their intensities for the period 1951 -2003 have been classified. Finally, an analysis has been performed comparing the new characteristics with the old ones for ENSO period, peak values and intensities. 展开更多
关键词 change of climate REFERENCE ENSO episodes INDICATORS
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A Study of Soil Nutrients in the Terrace Field Changed from Mountain Slope in Three Gorges Reservoir Region
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作者 Guojian CHEN Chunjuan LI +3 位作者 Chunli LI Juanjuan LI Jie WEI Hongwei DONG 《Asian Agricultural Research》 2016年第8期77-80,共4页
In order to accurately grasp the soil fertility in Three Gorges Reservoir Region after changing mountain slope into terrace field,we take Wushan County for example,and use the spatio-temporal substitution method to an... In order to accurately grasp the soil fertility in Three Gorges Reservoir Region after changing mountain slope into terrace field,we take Wushan County for example,and use the spatio-temporal substitution method to analyze the soil nutrient status and trend about the terrace field changed from mountain slope under different length of implementation.The results show that the soil fertility is generally low in the study area,and according to the soil nutrient grading standards in the second national land survey,the average content of total nitrogen,available potassium,organic matter and available phosphorus reaches Standard III,Standard III,Standard IV and Standard V,respectively,and the spatial heterogeneity of soil nutrients is small.Compared to the sloping land,the terrace field changed from mountain slope has increasing soil nutrients on the whole with the length of farming.The mean of various indicators about soil nutrients in the terrace field changed from mountain slope for 2 years is lower than in the sloping land,and there is the biggest difference in soil fertility,while the mean of various indicators about soil nutrients in the terrace field changed from mountain slope for 14 years shows a linear upward trend,and the difference in soil fertility decreases. 展开更多
关键词 Changing mountain slope into terrace field Soil nutrients Three Gorges Reservoir Region
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Effects of Changed Climate Conditions on Tropospheric Ozone over Three Centuries
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作者 Gitte Brandt Hedegaard Jesper Heile Christensen +5 位作者 Camilla Geels Allan Gross Kaj Mantzius Hansen Wilhelm May Azimeh Zare Jorgen Brandt 《Atmospheric and Climate Sciences》 2012年第4期546-561,共16页
The ozone chemistry in four decades (1890s, 1990s, 2090s and 2190s) representing the changes over three centuries has been simulated using the chemistry version of the atmospheric long-range transport model: the Danis... The ozone chemistry in four decades (1890s, 1990s, 2090s and 2190s) representing the changes over three centuries has been simulated using the chemistry version of the atmospheric long-range transport model: the Danish Eulerian Hemispheric Model (DEHM) forced with meteorology projected by theECHAM5/MPI-OM coupled Atmosphere-Ocean General Circulation Model. The largest changes in meteorology, ozone and its precursors are found in the 21st century, however, also significant changes are found in the 22nd century. At surface level the ozone concentration is projected to increase due to climate change in the areas where substantial amounts of ozone precursors are emitted. Elsewhere a significant decrease is projected at the surface. In the free troposphere a general increase is found in the entire Northern Hemisphere except in the tropics, where the ozone concentration is decreasing. In the Arctic the ozone concentration will increase in the entire air column, which most likely is due to changes in atmospheric transport. Changes in temperature, humidity and the naturally emitted Volatile Organic Compounds (VOCs) are governing the changes in ozone both in the past, present and future century. 展开更多
关键词 OZONE Climate Change Air Quality MODELLING
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Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease 被引量:6
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作者 Ming-Hui Zeng Qi-Yu Shi +1 位作者 Liang Xu Yu-Qiang Mi 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1393-1404,共12页
BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic burden.To date,no drugs have been approve... BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic burden.To date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of treatment.Identifying patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very important.AIM To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle interventions.METHODS The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently evaluated.Demographic and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 months.The efficacy of the EDAS was evaluated in the initial cohort.Subsequently,the efficacy of the EDAS was internally verified in a validation cohort.RESULTS The EDAS consisted of 33 items in six dimensions,with a total of 165 points.Total EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P<0.05 each),but not with overall weight loss.A total score of 116 was excellent in predicting adherence to daily reduction in calorie intake(>500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,and<97 points were indicative of good,average,and poor adherence,respectively,to diet and exercise recommendations.CONCLUSION The EDAS can reliably assess the adherence of patients with NAFLD to lifestyle interventions and have clinical application in this population. 展开更多
关键词 Fatty liver Lifestyle intervention Behavioral change Patient adherence COMPLIANCE
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uBlock算法的低延迟一阶门限实现方法
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作者 姚富 陈华 范丽敏 《电子学报》 EI CAS CSCD 北大核心 2024年第4期1250-1259,共10页
目前已有文献给出了uBlock分组密码算法的侧信道防护方案,但是这些方案不仅延迟较高,难以适用于低延迟高吞吐场景,而且在毛刺探测模型下缺乏可证明安全性.针对这一问题,本文给出了在毛刺探测模型下具有可证明安全性的uBlock算法的低延... 目前已有文献给出了uBlock分组密码算法的侧信道防护方案,但是这些方案不仅延迟较高,难以适用于低延迟高吞吐场景,而且在毛刺探测模型下缺乏可证明安全性.针对这一问题,本文给出了在毛刺探测模型下具有可证明安全性的uBlock算法的低延迟门限实现方案.此外,我们引入了Changing of the Guards技术来避免防护方案在执行过程中需要额外随机数.对于防护方案的安全性,我们用自动化评估工具SILVER验证了S盒的毛刺探测安全性,并用泄露评估技术TVLA(Test Vector Leakage Assessment)验证了防护方案的整个电路的安全性.最后,我们用Design Compiler工具对防护方案的性能消耗情况进行了评估.评估结果显示,与序列化实现方式的uBlock防护方案相比,我们的防护方案的延迟能够减少约95%. 展开更多
关键词 密码芯片 uBlock算法 侧信道攻击与防护 掩码技术 门限实现 Changing of the Guards
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Recent advances in graphene-based phase change composites for thermal energy storage and management 被引量:2
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作者 Qiang Zhu Pin Jin Ong +4 位作者 Si Hui Angela Goh Reuben J.Yeo Suxi Wang Zhiyuan Liu Xian Jun Loh 《Nano Materials Science》 EI CAS CSCD 2024年第2期115-138,共24页
Energy storage and conservation are receiving increased attention due to rising global energy demands.Therefore,the development of energy storage materials is crucial.Thermal energy storage(TES)systems based on phase ... Energy storage and conservation are receiving increased attention due to rising global energy demands.Therefore,the development of energy storage materials is crucial.Thermal energy storage(TES)systems based on phase change materials(PCMs)have increased in prominence over the past two decades,not only because of their outstanding heat storage capacities but also their superior thermal energy regulation capability.However,issues such as leakage and low thermal conductivity limit their applicability in a variety of settings.Carbon-based materials such as graphene and its derivatives can be utilized to surmount these obstacles.This study examines the recent advancements in graphene-based phase change composites(PCCs),where graphene-based nanostructures such as graphene,graphene oxide(GO),functionalized graphene/GO,and graphene aerogel(GA)are incorporated into PCMs to substantially enhance their shape stability and thermal conductivity that could be translated to better storage capacity,durability,and temperature response,thus boosting their attractiveness for TES systems.In addition,the applications of these graphene-based PCCs in various TES disciplines,such as energy conservation in buildings,solar utilization,and battery thermal management,are discussed and summarized. 展开更多
关键词 Phase change material NANOCOMPOSITES Solar energy Sustainable energy Thermo-regulation
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How do neurons age?A focused review on the aging of the microtubular cytoskeleton 被引量:1
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作者 Brad Richardson Thomas Goedert +2 位作者 Shmma Quraishe Katrin Deinhardt Amritpal Mudher 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1899-1907,共9页
Aging is the leading risk factor for Alzheimer’s disease and other neurodegenerative diseases. We now understand that a breakdown in the neuronal cytoskeleton, mainly underpinned by protein modifications leading to t... Aging is the leading risk factor for Alzheimer’s disease and other neurodegenerative diseases. We now understand that a breakdown in the neuronal cytoskeleton, mainly underpinned by protein modifications leading to the destabilization of microtubules, is central to the pathogenesis of Alzheimer’s disease. This is accompanied by morphological defects across the somatodendritic compartment, axon, and synapse. However, knowledge of what occurs to the microtubule cytoskeleton and morphology of the neuron during physiological aging is comparatively poor. Several recent studies have suggested that there is an age-related increase in the phosphorylation of the key microtubule stabilizing protein tau, a modification, which is known to destabilize the cytoskeleton in Alzheimer’s disease. This indicates that the cytoskeleton and potentially other neuronal structures reliant on the cytoskeleton become functionally compromised during normal physiological aging. The current literature shows age-related reductions in synaptic spine density and shifts in synaptic spine conformation which might explain age-related synaptic functional deficits. However, knowledge of what occurs to the microtubular and actin cytoskeleton, with increasing age is extremely limited. When considering the somatodendritic compartment, a regression in dendrites and loss of dendritic length and volume is reported whilst a reduction in soma volume/size is often seen. However, research into cytoskeletal change is limited to a handful of studies demonstrating reductions in and mislocalizations of microtubule-associated proteins with just one study directly exploring the integrity of the microtubules. In the axon, an increase in axonal diameter and age-related appearance of swellings is reported but like the dendrites, just one study investigates the microtubules directly with others reporting loss or mislocalization of microtubule-associated proteins. Though these are the general trends reported, there are clear disparities between model organisms and brain regions that are worthy of further investigation. Additionally, longitudinal studies of neuronal/cytoskeletal aging should also investigate whether these age-related changes contribute not just to vulnerability to disease but also to the decline in nervous system function and behavioral output that all organisms experience. This will highlight the utility, if any, of cytoskeletal fortification for the promotion of healthy neuronal aging and potential protection against age-related neurodegenerative disease. This review seeks to summarize what is currently known about the physiological aging of the neuron and microtubular cytoskeleton in the hope of uncovering mechanisms underpinning age-related risk to disease. 展开更多
关键词 age-related changes AGING CYTOSKELETON MICROTUBULES neuronal morphology
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Global Change in Agricultural Flash Drought over the 21st Century 被引量:1
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作者 Emily BLACK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期209-220,I0002-I0019,共30页
Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop... Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa. 展开更多
关键词 flash drought climate change soil moisture agricultural drought CMIP
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Shikimic acid accelerates phase change and flowering in Chinese jujube 被引量:1
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作者 Xianwei Meng Zhiguo Liu +11 位作者 Li Dai Weiqiang Zhao Jiurui Wang Lili Wang Yuanpei Cui Ying Li Yinshan Cui Yao Zhang Luyao Wang Fengjiao Yu Jin Zhao Mengjun Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期413-424,共12页
The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely un... The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely unknown. Shikimic acid (ShA) pathway is a main metabolic pathway closely related to the synthesis of hormones and many important secondary metabolites participating in plant phase change. So,whether ShA regulates phase change in plants is worth clarifying. Here, the distinct morphological characteristics and the underlying mechanisms of phase change in jujube (Ziziphus jujuba Mill.), an important fruit tree native to China with nutritious fruit and outstanding tolerance abiotic stresses, were clarified. A combined transcriptome and metabolome analysis found that ShA is positively involved in jujube(Yuhong’×Xing 16’) phase change. The genes in the upstream of ShA synthesis pathway (ZjDAHPS, ZjDHQS and ZjSDH), the contents of ShA and the downstream secondary metabolites like phenols were significantly upregulated in the phase change period. Further, the treatment of spraying exogenous ShA verified that ShA at a very low concentration (60 mg·L^(-1)) can substantially speed up the phase change and flowering of jujube and other tested plants including Arabidopsis, tomato and wheat. The exogenous ShA (60 mg·L^(-1)) treatment in jujube seedlings could increase the accumulation of endogenous ShA, enhance leaf photosynthesis and the synthesis of phenols especially flavonoids and phenolic acids, and promote the expression of genes (ZjCOs, ZjNFYs and ZjPHYs) involved in flowering pathway. Basing on above results, we put forward a propose for the underlying mechanism of ShA regulating phase change, and a hypothesis that ShA could be considered a phytohormone-like substance because it is endogenous, ubiquitous, movable and highly efficient at very low concentrations. This study highlights the critical role of ShA in plant phase change and its phytohormone-like properties. 展开更多
关键词 Ziziphus jujuba Mill. Phase change FLOWERING Shikimic acid TRANSCRIPTOME METABOLOME
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Plastid phylogenomics provides new insights into the systematics,diversification,and biogeography of Cymbidium(Orchidaceae) 被引量:1
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作者 Hai-Yao Chen Zhi-Rong Zhang +7 位作者 Xin Yao Ji-Dong Ya Xiao-Hua Jin Lin Wang Lu Lu De-Zhu Li Jun-Bo Yang Wen-Bin Yu 《Plant Diversity》 SCIE CAS CSCD 2024年第4期448-461,共14页
Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,... Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,phylogenetic relationships of Cymbidium have not been well resolved,hampering investigations of species diversification and the biogeographical history of this genus.In this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate analyses.Molecular dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern IndoBurma to the eastern Himalayas during the early Miocene(~21.10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle Miocene.Cymbidium spp.migration to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene period.Our analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon intensity.Favorable hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle Miocene.The transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification rates.This study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia. 展开更多
关键词 CYMBIDIUM East Asia Asian monsoons Climate change Biogeographical patterns
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A review of methane leakage from abandoned oil and gas wells:A case study in Lubbock,Texas,within the Permian Basin 被引量:2
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作者 Stanley U.Opara Chinedu J.Okere 《Energy Geoscience》 EI 2024年第3期1-12,共12页
In the pursuit of global net zero carbon emissions and climate change mitigation,ongoing research into sustainable energy sources and emission control is paramount.This review examines methane leakage from abandoned o... In the pursuit of global net zero carbon emissions and climate change mitigation,ongoing research into sustainable energy sources and emission control is paramount.This review examines methane leakage from abandoned oil and gas(AOG)wells,focusing particularly on Lubbock,a geographic area situated within the larger region known as the Permian Basin in West Texas,United States.The objective is to assess the extent and environmental implications of methane leakage from these wells.The analysis integrates pertinent literature,governmental and industry data,and prior Lubbock reports.Factors affecting methane leakage,including well integrity,geological characteristics,and human activities,are explored.Our research estimates 1781 drilled wells in Lubbock,forming a foundation for targeted assessments and monitoring due to historical drilling trends.The hierarchy of well statuses in Lubbock highlights the prevalence of“active oil wells,”trailed by“plugged and abandoned oil wells”and“inactive oil wells.”Methane leakage potential aligns with these well types,underscoring the importance of strategic monitoring and mitigation.The analysis notes a zenith in“drilled and completed”wells during 1980-1990.While our study's case analysis and literature review reiterate the critical significance of assessing and mitigating methane emissions from AOG wells,it's important to clarify that the research does not directly provide methane leakage data.Instead,it contextualizes the issue's magnitude and emphasizes the well type and status analysis's role in targeted mitigation efforts.In summary,our research deepens our understanding of methane leakage,aiding informed decision-making and policy formulation for environmental preservation.By clarifying well type implications and historical drilling patterns,we aim to contribute to effective strategies in mitigating methane emissions from AOG wells. 展开更多
关键词 Net zero carbon emissions Climate change mitigation Methane emission control Abandoned oil and gas(AOG)well Permian Basin
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Self‑Assembly of Binderless MXene Aerogel for Multiple‑Scenario and Responsive Phase Change Composites with Ultrahigh Thermal Energy Storage Density and Exceptional Electromagnetic Interference Shielding 被引量:1
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作者 Chuanbiao Zhu Yurong Hao +8 位作者 Hao Wu Mengni Chen Bingqing Quan Shuang Liu Xinpeng Hu Shilong Liu Qinghong Ji Xiang Lu Jinping Qu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期367-382,共16页
The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here... The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here,we introduced metal ions to induce the self-assembly of MXene nanosheets and achieve their ordered arrangement by combining suction filtration and rapid freezing.Subsequently,a series of MXene/K^(+)/paraffin wax(PW)phase change composites(PCCs)were obtained via vacuum impregnation in molten PW.The prepared MXene-based PCCs showed versatile applications from macroscale technologies,successfully transforming solar,electric,and magnetic energy into thermal energy stored as latent heat in the PCCs.Moreover,due to the absence of binder in the MXene-based aerogel,MK3@PW exhibits a prime solar-thermal conversion efficiency(98.4%).Notably,MK3@PW can further convert the collected heat energy into electric energy through thermoelectric equipment and realize favorable solar-thermal-electric conversion(producing 206 mV of voltage with light radiation intensity of 200 mw cm^(−2)).An excellent Joule heat performance(reaching 105℃with an input voltage of 2.5 V)and responsive magnetic-thermal conversion behavior(a charging time of 11.8 s can achieve a thermal insulation effect of 285 s)for contactless thermotherapy were also demonstrated by the MK3@PW.Specifically,as a result of the ordered arrangement of MXene nanosheet self-assembly induced by potassium ions,MK3@PW PCC exhibits a higher electromagnetic shielding efficiency value(57.7 dB)than pure MXene aerogel/PW PCC(29.8 dB)with the same MXene mass.This work presents an opportunity for the multi-scene response and practical application of PCMs that satisfy demand of next-generation multifunctional PCCs. 展开更多
关键词 Self-assembly Multiple-scenario Phase change composites Thermal energy storage Electromagnetic interference shielding
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