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Cost-Effectiveness Analysis of Combined Chemotherapy Regimen Containing Bedaquiline in the Treatment of Multidrug-Resistant Tuberculosis in China 被引量:1
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作者 XU Cai Hong QIU Ying Peng +5 位作者 HE Zi Long HU Dong Mei YUE Xiao CHEN Zhong Dan XU Yuan Yuan ZHAO Yan Lin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第6期501-509,共9页
Objective This study aims to estimate the cost-effectiveness of the combined chemotherapy regimen containing Bedaquiline(BR)and the conventional treatment regimen(CR,not containing Bedaquiline)for the treatment of adu... Objective This study aims to estimate the cost-effectiveness of the combined chemotherapy regimen containing Bedaquiline(BR)and the conventional treatment regimen(CR,not containing Bedaquiline)for the treatment of adults with multidrug-resistant tuberculosis(MDR-TB)in China.Methods A combination of a decision tree and a Markov model was developed to estimate the cost and effects of MDR patients in BR and CR within ten years.The model parameter data were synthesized from the literature,the national TB surveillance information system,and consultation with experts.The incremental cost-effectiveness ratio(ICER)of BR vs.CR was determined.Results BR(vs.CR)had a higher sputum culture conversion rate and cure rate and prevented many premature deaths(decreased by 12.8%),thereby obtaining more quality-adjusted life years(QALYs)(increased by 2.31 years).The per capita cost in BR was as high as 138,000 yuan,roughly double that of CR.The ICER for BR was 33,700 yuan/QALY,which was lower than China's 1×per capita Gross Domestic Product(GDP)in 2020(72,400 yuan).Conclusion BR is shown to be cost effective.When the unit price of Bedaquiline reaches or falls below57.21 yuan per unit,BR is expected to be the dominant strategy in China over CR. 展开更多
关键词 Bedaquiline COST-EFFECTIVENESS Multidrug-resistant tuberculosis China
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Discursive Construction of Chinese Military Image in the British Media
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作者 AN Xue-ying ZHI Yong-bi 《Journal of Literature and Art Studies》 2023年第5期362-371,共10页
This study takes the image of China’s military as c onstructed in the British media’s military coverage of China as an object of study,and creates two reference corpora for comparative research.It is used to better ... This study takes the image of China’s military as c onstructed in the British media’s military coverage of China as an object of study,and creates two reference corpora for comparative research.It is used to better analyse and compare the ideologies hidden in the British media’s coverage of China’s milita ry.From the analysis of the corpus,it is concluded that due to China’s rapid military and economic development,Western countries have developed a sense of crisis and have used media reports to instigate China’s foreign relations and mislead public think ing. 展开更多
关键词 discursive construction Chinese military image CORPUS British media
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Electromagnetic Performance Analysis of Variable Flux Memory Machines with Series-magnetic-circuit and Different Rotor Topologies
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作者 Qiang Wei Z.Q.Zhu +4 位作者 Yan Jia Jianghua Feng Shuying Guo Yifeng Li Shouzhi Feng 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期3-11,共9页
In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor topologies.Based on a V-type VFM machine,five topologies... In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor topologies.Based on a V-type VFM machine,five topologies with different interior permanent magnet(IPM)arrangements are evolved and optimized under same constrains.Based on two-dimensional(2-D)finite element(FE)method,their electromagnetic performance at magnetization and demagnetization states is evaluated.It reveals that the iron bridge and rotor lamination region between constant PM(CPM)and variable PM(VPM)play an important role in torque density and flux regulation(FR)capabilities.Besides,the global efficiency can be improved in VFM machines by adjusting magnetization state(MS)under different operating conditions. 展开更多
关键词 Memory machine Permanent magnet Rotor topologies Series magnetic circuit Variable flux
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Coupling coordination analysis of Mazu culture,socio-economy and ecological environment of Meizhou Island
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作者 FU Wei-jia WU Ying-qi +2 位作者 LUO Zi-xuan YAO Jun-bing FU Li-jun 《Ecological Economy》 2024年第1期85-100,共16页
Taking the pilgrimage,tourism and cultural island of Meizhou Island as an example,the evaluation index system of the coupling and coordinated development of“Mazu culture,socio-economy,eco-environment”(MSE)compound s... Taking the pilgrimage,tourism and cultural island of Meizhou Island as an example,the evaluation index system of the coupling and coordinated development of“Mazu culture,socio-economy,eco-environment”(MSE)compound system was constructed.The index weights were determined by AHP-entropy method,and the coupling degree,coordinated degree,comprehensive evaluation index and grey correlation degree of MSE system of Mazu Island from 2012 to 2022 were measure.The results showed that:(1)the comprehensive evaluation indexes of the three subsystems was on the rise in general,but the evaluation index of the ecological subsystems increased relatively slowly.(2)The coupling degree was only in the running-in stage in 2012,and the other years were in the coordinated coupling stage.(3)The coupling coordination degree increased from 0.35 in 2012 to 0.82 in 2022,the coupling coordination level was changed from mild imbalance to good coordination.(4)Through the comparison of grey correlation degree,the 24 indexes in the evaluation index system had great influence on the coupling coordination degree of MSE system.The coupling coordination degree was closely related to the development of socio-economy and the spread of Mazu culture.With the rapid development of tourism brought about by the spread of Mazu culture,the pressure on the ecological environment will be increasing.Compared with the rapid growth of tourism and economy,it is equally important to strengthen environmental protection and pay attention to the quality of ecological environment development. 展开更多
关键词 Meizhou Island Mazu culture socio-economy ecological environment comprehensive evaluation index coupling coordination degree
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Multiple lines of evidence confirm that the critically endangered Blue-crowned Laughingthrush(Garrulax courtoisi)is an independent species 被引量:2
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作者 Tao Liu Yongtao Xu +5 位作者 Canwei Xia David Edwards Xiaolong Hu Yingyu Su Jinsheng Xie Weiwei Zhang 《Avian Research》 SCIE CSCD 2022年第3期256-264,共9页
The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully el... The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully elucidated.So the taxonomic status and system evolution of the three taxa G.courtoisi,G.galbanus and G.c.simaoensis need to be reclarified.Two gene sequences myoglobin(MYO)and the mitochondrial cytochrome coxidase subunit I(COI)were combined to investigate the phylogenetic relationships among courtoisi,simaoensis and galbanus,genetic data,combining with morphological,ecological and acoustic data were used to comb out the classification status and divergence level of the three taxa.Significant genetic and morphological differentiations(body size and plumage coloration)were detected between courtoisi and galbanus.However,no notable and reliable differences between the courtoisi and simaoensis were detected.The courtoisi,simaoensis and galbanus are clearly isolated in geographical distribution as a result of differing altitudes,climate conditions and habitats.The courtoisi has characteristic preference for nest location compared with galbanus.In addition,the results of song analysis also indicated that there are differences in maximum frequency between courtoisi and galbanus.G.courtoisi was confirmed to be an independent species based on genetic,morphological,geographical,ecological and vocal characteristics,and the validity of simaoensis as a subspecies still need more evidence.This study further confirmed the high conservation value of Blue-crowned Laughingthrush.In addition,due to the genetic differences between Simao and Wuyuan populations,this should be fully considered in future protection strategies. 展开更多
关键词 Garrulax courtoisi Garrulax galbanus GENETICS Morphology Taxonomy Vocalization
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eHealth,telehealth,and telemedicine in the management of the COVID-19 pandemic and beyond:Lessons learned and future perspectives 被引量:1
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作者 Andrea Giacalone Luca Marin +2 位作者 Massimiliano Febbi Thomas Franchi Marcos Roberto Tovani-Palone 《World Journal of Clinical Cases》 SCIE 2022年第8期2363-2368,共6页
In this article,we discuss evidence supporting the effective implementation of e Health,telehealth,and telemedicine during the coronavirus disease 2019 pandemic,with a view towards its permanent future integration in ... In this article,we discuss evidence supporting the effective implementation of e Health,telehealth,and telemedicine during the coronavirus disease 2019 pandemic,with a view towards its permanent future integration in healthcare.We performed a literature search for articles describing the use of telehealth/telemedicine in the pandemic context using five databases.The articles selected describe the use of telemedicine as its advantages in terms of practicality and costeffectiveness.This synthesis of articles is applicable to high-,middle-and lowincome countries.Some of the notable benefits include breaking down geographical and time barriers,reducing waiting lists and crowding in healthcare facilities,and saving on national healthcare expenditure.However,there are a number of difficulties with the widespread implementation of telemedicine services that mainly relate to bureaucratic and regulatory concerns.Moreover,it is also important to make healthcare professionals and providers aware of the limits of this tool to avoid potential cases of negligence.Patients in turn will have to be made aware of and be educated on the use of this new healthcare modality before it is accepted by them.In the current socio-economic climate,it is therefore essential to implement a telehealth model aimed at efficiency and continuity of healthcare,as well as leading to an improvement in the quality of life of patients,whilst optimising existing resources and reducing costs.In that regard,the adoption of e Health,telehealth,and telemedicine services should be considered highly timely,despite current existing limitations. 展开更多
关键词 EHEALTH TELEHEALTH TELEMEDICINE Coronavirus disease 2019 Pandemics Delivery of healthcare
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The Study of the Impact of Mercury Sample Magnetization Prior to Detection by Emission Spectroscopy 被引量:1
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作者 Wameath S. Abdul-Majeed William B. Zimmerman 《Journal of Environmental Science and Engineering(A)》 2012年第3期380-387,共8页
Experimental investigations were conducted in this study to explore the effect of magnetization on water sample properties and to envisage whether the effect is beneficial for mercury detection in a sample of water or... Experimental investigations were conducted in this study to explore the effect of magnetization on water sample properties and to envisage whether the effect is beneficial for mercury detection in a sample of water or not. Subjecting the water sample to 0.3 Tesla magnetic field for 14 hours led to instantaneous effects on the examined water properties, where a reduction in the values of pH (7%) and interfacial tension (0.2%) was observed, whereas an increase (8%) in water electrical conductivity was recorded. Similar behaviours with slight changes in trend were observed after storing the samples for six days, which indicates a creation of permanent effects. Other experiments were conducted to explore the impact of magnetizing water sample containing inorganic mercury prior to detection by emission spectroscopy. Samples were prepared with different mercury concentrations and derivatized by using tin chloride (SnCI2). The generated mercury vapour species were transported with aid of carrier gas into a dielectric barrier discharge plasma atomizer, in which the mercury signal at 253.65 nm was recorded. The results have shown 3.5%-7.5% increase in the signal intensities recorded for the magnetized samples, mostly attributed to a reduction in the sample surface tension and other reasons, which facilitates analyte derivatization. 展开更多
关键词 Water magnetization DBD plasma atomic emission spectroscopy heavy metals.
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Noninvasive stiffness assessment of the human lens nucleus in patients with anisometropia using an ultrasound elastography system 被引量:1
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作者 Hai-Yan Zhou Hong Yan +2 位作者 Wei-Jia Yan Xin-Chuan Wang Qiao-Ying Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第3期399-405,共7页
AIM:To investigate the significance of ultrasound elastography for evaluating stiffness of the human lens nucleus in patients with anisometropia.METHODS:A total of 14 patients(28 eyes)with anisometropia were enrolled.... AIM:To investigate the significance of ultrasound elastography for evaluating stiffness of the human lens nucleus in patients with anisometropia.METHODS:A total of 14 patients(28 eyes)with anisometropia were enrolled.The difference in refractive status between two eyes≥-4.0 diopters(D)and the difference in axial length(AL)of the eyes was≥3 mm.There were 5 males and 9 females with an average age of 62±3.3 y.The test data of the long AL eye of each patient was included in group A(14 eyes),and test data of the eye with relative short AL was included in group B.Lens nuclear stiffness was measured with free-hand qualitative elastography by independent operators.Strain gray scale and color-coded elastography maps were recorded.In each case,three consecutive measurements were performed and strain ratio was used for statistical analysis.Photograph and sectional view of the lens were analyzed and archived by anterior segment image.RESULTS:In the long AL group,the strain rate in the nucleus of the lens was 0.16%±0.08%;in the short AL group,the strain rate in the nucleus of the lens was 0.54%±0.16%.Independent sample t-test analyses showed that the long AL group lens had a significantly smaller nuclear strain rate than the relatively short AL group,P<0.05.CONCLUSION:The relationship between human lens stiffness and different AL is demonstrated by ultrasound elastography.The long AL is associated with lower strain ratio and less resilience of the lens. 展开更多
关键词 ULTRASOUND ELASTOGRAPHY human lensnucleus STIFFNESS ANISOMETROPIA
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Computational Modelling of the Hydride Generation Reaction in a Tubular Reactor and Atomization in a Quartz Cell Atomizer 被引量:1
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作者 Wameath S. Abdul-Majeed William B. Zimmerman 《Journal of Analytical Sciences, Methods and Instrumentation》 2012年第3期126-139,共14页
In this study, we present a model whereby the centre of the atomization channel is shown to be the optimal location for the spectrometric data acquisition in a quartz cell atomizer. The study aims to explore the hydri... In this study, we present a model whereby the centre of the atomization channel is shown to be the optimal location for the spectrometric data acquisition in a quartz cell atomizer. The study aims to explore the hydride generation technique which is normally coupled with efficient thermal source to apply determination of heavy metals in water samples via spectrometric analysis. The arsenic hydride generation process and the atomization of the generated hydride in a quartz cell atomizer were studied analytically as model case studies. The hydride generation (HG) process was analyzed by adopting two hypotheses, the nascent hydrogen and formation of intermediate hydroboron species, where the results based on the second hypothesis are found to be more realistic for design purposes. Moreover, the release of the generated hydride from the liquid phase and their transport to the gas phase is simulated in a helical tubular section, in which the actual tubular section length required for separation is deduced. The analytical results have been verified experimentally by measuring the signal intensity for the free arsenic atoms against several reaction tube lengths, in which increasing the tubular section length from 12 cm to 100 cm results in signal amelioration by no more than 6.6%. Furthermore, the atomization of the hydride and the distribution of the generated free atoms are deduced in two configurations of tubular quartz atomizers. The results obtained from both studied cases illustrate that a high concentration of the free analyte atoms is generated in the first part of the atomization channel, saturates to a maximum in a position at the atomizer centre, and dissipates at the inside wall of the tubular atomizer before reaching the atomizer outlet edge, which is found to be in total agreement with the current understanding of atomization mechanism in tubular atomizer and emphasizes the fact that the centre of the quartz cell atomizer is the best location for the spectrometric data acquisition. 展开更多
关键词 HYDRIDE Generation Process TUBULAR Reactor QUARTZ CELL ATOMIZER Emission Spectroscopy
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The biomechanical role of periodontal ligament in bonded and replanted vertically fractured teeth under cyclic biting forces 被引量:1
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作者 Ya-Nan Zhu Wei-Dong Yang +5 位作者 Paul V Abbott Nicolas Martin Wen-Jia Wei Jing-Jing Li Zhi Chen Wen-Mei Wang 《International Journal of Oral Science》 SCIE CAS CSCD 2015年第2期125-130,共6页
After teeth are replanted,there are two possible healing responses:periodontal ligament healing or ankylosis with subsequent replacement resorption.The purpose of this study was to compare the fatigue resistance of v... After teeth are replanted,there are two possible healing responses:periodontal ligament healing or ankylosis with subsequent replacement resorption.The purpose of this study was to compare the fatigue resistance of vertically fractured teeth after bonding the fragments under conditions simulating both healing modes.Thirty-two human premolars were vertically fractured and the fragments were bonded together with Super-Bond C&B.They were then randomly distributed into four groups(BP,CP,CA,BA).The BP and CP groups were used to investigate the periodontal ligament healing mode whilst the BA and CA groups simulated ankylosis.All teeth had root canal treatment performed.Metal crowns were constructed for the CP and CA groups.The BP and BA groups only had composite resin restorations in the access cavities.All specimens were subjected to a 260 N load at 4 Hz until failure of the bond or until 2 x 106 cycles had been reached if no fracture occurred.Cracks were detected by stereomicroscope imaging and also assessed via dye penetration tests.Finally,interfaces of the resin luting agent were examined by scanning electron microscope.The results confirmed that the fatigue resistance was higher in the groups with simulated periodontal ligament healing.Periodontal reattachment showed important biomechanical role in bonded and replanted vertically fractured teeth. 展开更多
关键词 fractured vertically teeth periodontal ligament bonding bonded resin subsequent restoration
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“Data Hegemony”: Reflections for the Application and Development Direction of Metaverse Technology in Urban Design based on Digital 被引量:1
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作者 Qinyu Feng Renjie Cai 《Journal of World Architecture》 2021年第6期52-61,共10页
This paper is based on the phenomenon of Tittytainment and big data control.It discusses the ways in which working youths live and work in their large suburban communities in Beijing as well as their leisure and enter... This paper is based on the phenomenon of Tittytainment and big data control.It discusses the ways in which working youths live and work in their large suburban communities in Beijing as well as their leisure and entertainment activities.Then develops a problem statement and research questions.In addition,the project explores this reality phenomenon dialectically through the analysis and speculation of the new virtual reality technology“Metaverse.”Based on a critical design approach,the phenomenon is explored through a detailed description and examination of reality,before critically suggesting the possibility of future social control by big data companies through the“metaverse”space.Furthermore,this paper alerts to the neoliberalism that dominates globalization through anti-utopian expressions,waking up young people who are compromised by big data control and addicted to Tittytainment. 展开更多
关键词 Urban design Metaverse technology Big data Neoliberalism
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Review of a direct epitaxial approach to achieving micro-LEDs 被引量:1
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作者 蔡月飞 白洁 王涛 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期22-29,共8页
There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabri... There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabricated by dry-etching technologies, unavoidably leading to a severe degradation in optical performance as a result of dry-etching induced damages. This becomes a particularly severe issue when the dimension of LEDs is ≤ 10 μm. In order to address the fundamental challenge, the Sheffield team has proposed and then developed a direct epitaxial approach to achievingμLEDs, where the dry-etching technologies for the formation of μLED mesas are not needed anymore. This paper provides a review on this technology and then demonstrates a number of monolithically integrated devices on a single chip using this technology. 展开更多
关键词 micro-LED epitaxial growth gallium nitride DISPLAY
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The dynamic relaxation form finding method aided with advanced recurrent neural network 被引量:1
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作者 Liming Zhao Zhongbo Sun +1 位作者 Keping Liu Jiliang Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第3期635-644,共10页
How to establish a self‐equilibrium configuration is vital for further kinematics and dynamics analyses of tensegrity mechanism.In this study,for investigating tensegrity form‐finding problems,a concise and efficien... How to establish a self‐equilibrium configuration is vital for further kinematics and dynamics analyses of tensegrity mechanism.In this study,for investigating tensegrity form‐finding problems,a concise and efficient dynamic relaxation‐noise tolerant zeroing neural network(DR‐NTZNN)form‐finding algorithm is established through analysing the physical properties of tensegrity structures.In addition,the non‐linear constrained opti-misation problem which transformed from the form‐finding problem is solved by a sequential quadratic programming algorithm.Moreover,the noise may produce in the form‐finding process that includes the round‐off errors which are brought by the approximate matrix and restart point calculating course,disturbance caused by external force and manufacturing error when constructing a tensegrity structure.Hence,for the purpose of suppressing the noise,a noise tolerant zeroing neural network is presented to solve the search direction,which can endow the anti‐noise capability to the form‐finding model and enhance the calculation capability.Besides,the dynamic relaxation method is contributed to seek the nodal coordinates rapidly when the search direction is acquired.The numerical results show the form‐finding model has a huge capability for high‐dimensional free form cable‐strut mechanisms with complicated topology.Eventually,comparing with other existing form‐finding methods,the contrast simulations reveal the excellent anti‐noise performance and calculation capacity of DR‐NTZNN form‐finding algorithm. 展开更多
关键词 dynamic relaxation form‐finding noise‐tolerant zeroing neural network sequential quadratic programming TENSEGRITY
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Special issue on carbon capture in the context of carbon capture, utilisation and storage (CCUS)
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作者 Meihong Wang Eni Oko 《International Journal of Coal Science & Technology》 EI 2017年第1期1-4,共4页
With global energy demand predicted to rise as the world population increases, there is a serious challenge to ensure energy security and also to reduce CO2 emissions. Atmo- spheric CO2 levels will reach about 800 ppm... With global energy demand predicted to rise as the world population increases, there is a serious challenge to ensure energy security and also to reduce CO2 emissions. Atmo- spheric CO2 levels will reach about 800 ppm by 2100 resulting in about 4 ℃ rise in the earth surface temperature if no action is taken (CO2 Earth 2017). At the 21st Con- ference of Parties (COP21) to the United Nations Frame- work Convention on Climate Change (UNFCCC) held in Paris, France from 30th November to 12th December 2015, 195 nations historically agreed to "combat climate change and unleash actions and investment towards a low carbon, resilient and sustainable future" with the aim to ensure global temperature rise is kept well below 2℃ (UNFCCC 2015). To achieve this aim, a portfolio of technologies have been proposed, one of which is carbon capture, utilization and storage (CCUS) (Dixon 2016). 展开更多
关键词 二氧化碳排放量 联合国气候变化框架公约 捕获 大气CO2浓度 上下文 存储 捕捉 温度上升
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A Social Intervention Approach to Rehabilitate the Health Psychology of Leftbehind Children with Psychological Problems in Healthcare Settings
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作者 Qijie Jiang Chi Zhang +1 位作者 Xiaoli Duan Siyi Pei 《International Journal of Mental Health Promotion》 2022年第3期415-423,共9页
Background:Left-behind children are more inclined to generate psychological problems relative to non-leftbehind children,thus how to rehabilitate their health psychology and promote the psychological health developmen... Background:Left-behind children are more inclined to generate psychological problems relative to non-leftbehind children,thus how to rehabilitate their health psychology and promote the psychological health development of this special disadvantaged group in healthcare settings should be paid more attention to.Objective:This paper attempts to present a social intervention approach and explore its impact on the rehabilitation of rural leftbehind children’s psychological problems in healthcare settings.Methods:This study firstly designed a social intervention program based on the health psychology theory and the generation causes of left-behind children’s psychological problems,and then three groups were applied to test the effectiveness of the program with comparison analysis.Results:Compared with the control left-behind children(group 2),the left-behind children in the experimental group 1 had positive changes in learning anxiety,physical symptoms,anxiety about people,loneliness tendency,self-blame tendency,allergy tendency,terror tendency and impulse tendency.And their mental health can be rehabilitated to the level of non-left-behind children in group 3.Conclusion:This study revealed positive effects of specially designed social intervention program on the rehabilitation of left-behind children’s psychological problems in healthcare settings.The results have both theoretical and practical implications. 展开更多
关键词 Health psychology left-behind children REHABILITATION healthcare settings EXPERIMENT
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Ultrasound elastography for evaluating stiffness of the human lens nucleus with aging:a feasibility study
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作者 Hai-Yan Zhou Hong Yan +1 位作者 Wei-Jia Yan Xin-Chuan Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第2期240-244,共5页
AIM:To investigate the significance of ultrasound elastography for evaluating stiffness of the human lens nucleus in volunteers with different ages.METHODS:A total of 90 volunteers(lens transparency,uncorrected visual... AIM:To investigate the significance of ultrasound elastography for evaluating stiffness of the human lens nucleus in volunteers with different ages.METHODS:A total of 90 volunteers(lens transparency,uncorrected visual acuity≥0.5,intraocular pressure:14-19 mm Hg)were divided into 3 groups according to age:Group A(30 people,median age:82±3.5 y,mean axial lengths 23.7±0.5 mm);Group B(30 people,median age:46±2.1 y,mean axial lengths 23.9±0.4 mm);and Group C(30 people,median age:22±3.5 y,mean axial lengths 24.0±0.4 mm).Lens nuclear stiffness was measured by Free-hand qualitative elastography by independent operators.Strain gray scale and color-coded elastography maps were recorded.In each case,three consecutive detections were performed and strain ratio was used for statistical analysis.RESULTS:Elastography analysis showed excellent diagnostic performance for lens sclerosis.Lens strain ratio was lowest(0.03±0.01)%in Group A and highest(2.03±0.43)%in Group C.Lens strain ratio was moderate(0.64±0.10)%in Group B.There were significant differences between these three groups(P<0.05).The lens nucleus strain rate changes with age.With aging,the lens nucleus strain rate and resilience decrease,demonstrating harder texture.CONCLUSION:The relationship between human lens stiffness and age is demonstrated by ultrasound elastography.Older age is associated with lower strain ratio and less resilience of the lens. 展开更多
关键词 ultrasound elastography human lens nucleus STIFFNESS
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Internet Technology in Startup Businesses and Their Contribution to the Development of Entrepreneurship in Greece
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作者 Nikolaos Raptis Vasiliki Delitheou Charalampos Trasanidis 《International Relations and Diplomacy》 2020年第3期110-119,共10页
This paper examines the impact of Internet technology on emerging businesses and its contribution to the development of entrepreneurship in Greece.It emphasizes the importance of start-ups in the business ecosystem an... This paper examines the impact of Internet technology on emerging businesses and its contribution to the development of entrepreneurship in Greece.It emphasizes the importance of start-ups in the business ecosystem and the creation of favorable conditions for the development of innovative business ideas.In addition,a theoretical approach of basic concepts of the ecosystem of the startups is carried out which,in combination with the quantitative research that follows,attempts to answer the question whether the development of Internet technology affects entrepreneurship in Greece currently and in the future. 展开更多
关键词 ENTREPRENEURSHIP INNOVATION Internet startup ecosystem technology
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On the Essentiality of Pre-listening in English Listening Teaching
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作者 Wang Zhengrui 《基础教育外语教学研究》 2011年第1期33-37,共5页
关键词 摘要 编辑部 编辑工作 读者
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The Long-term Survival Chances of Young Massive Star Clusters
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作者 Richard de Grijs Geneviève Parmentier 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第2期155-186,共32页
We review the long-term survival chances of young massive star clusters (YMCs), hallmarks of intense starburst episodes often associated with Violent galaxy interactions. We address the key question as to whether at... We review the long-term survival chances of young massive star clusters (YMCs), hallmarks of intense starburst episodes often associated with Violent galaxy interactions. We address the key question as to whether at least some of these YMCs can be considered protoglobular clusters (GCs), in which case these would be expected to evolve into counterparts of the ubiquitous old GCs believed to be among the oldest galactic building blocks. In the absence of significant external perturbations, the key factor determining a cluster's long-term survival chances is the shape of its stellar initial mass function (IMF). It is, however, not straightforward to assess the IMF shape in unresolved extragalactic YMCs. We discuss in detail the promise of using high-resolution spectroscopy to make progress towards this goal, as well as the numerous pitfalls associated with this approach. We also discuss the latest progress in worldwide efforts to better understand the evolution of entire cluster systems, the disruption processes they are affected by, and whether we can use recently gained insights to determine the nature of at least some of the YMCs observed in extragalactic starbursts as proto-GCs. We conclude that there is an increasing body of evidence that GC formation appears to be continuing until today; their long-term evolution crucially depends on their environmental conditions, however. 展开更多
关键词 stellar dynamics - globular clusters general - galaxies interactions - Magellanic Clouds - galaxies starburst - galaxies star clusters
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Serine and arginine rich splicing factor 1:a potential target for neuroprotection and other diseases
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作者 Ana M.Sandoval-Castellanos Anushka Bhargava +2 位作者 Min Zhao Jun Xu Ke Ning 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1411-1416,共6页
Alternative splicing is the process of producing variably spliced mRNAs by choosing distinct combinations of splice sites within a messenger RNA precursor.This splicing enables mRNA from a single gene to synthesize di... Alternative splicing is the process of producing variably spliced mRNAs by choosing distinct combinations of splice sites within a messenger RNA precursor.This splicing enables mRNA from a single gene to synthesize different proteins,which have different cellular properties and functions and yet arise from the same single gene.A family of splicing factors,Serine-arginine rich proteins,are needed to initiate the assembly and activation of the spliceosome.Serine and arginine rich splicing factor 1,part of the arginine/serine-rich splicing factor protein family,can either activate or inhibit the splicing of mRNAs,depending on the phosphorylation status of the protein and its interaction partners.Considering that serine and arginine rich splicing factor 1 is either an activator or an inhibitor,this protein has been studied widely to identify its various roles in different diseases.Research has found that serine and arginine rich splicing factor 1 is a key target for neuroprotection,showing its promising potential use in therapeutics for neurodegenerative disorders.Furthermore,serine and arginine rich splicing factor 1 might be used to regulate cancer development and autoimmune diseases.In this review,we highlight how serine and arginine rich splicing factor 1 has been studied concerning neuroprotection.In addition,we draw attention to how serine and arginine rich splicing factor 1 is being studied in cancer and immunological disorders,as well as how serine and arginine rich splicing factor 1 acts outside the central or peripheral nervous system. 展开更多
关键词 alternative splicing autoimmune disorders cancer HYPERTENSION mRNA NEUROPROTECTION splicing factors SRSF1
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