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Late Cretaceous non-avian dinosaurs from the James Ross Basin,Antarctica:description of new material,updated synthesis,biostratigraphy,and paleobiogeography 预览
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作者 Matthew CLAMANNA Judd ACASE +7 位作者 Eric MROBERTS Victoria MARBOUR Ricardo CELY Steven WSALISBURY Julia ACLARKE DEdward MALINZAK Abagael RWEST Patrick MO’CONNOR 《极地科学进展:英文版》 CSCD 2019年第3期228-250,共23页
Although the fossil record of non-avian dinosaurs from the Cretaceous of Antarctica is the poorest of any continent,fossils representing at least five major taxonomic groups(Ankylosauria,early-diverging Ornithopoda,Ha... Although the fossil record of non-avian dinosaurs from the Cretaceous of Antarctica is the poorest of any continent,fossils representing at least five major taxonomic groups(Ankylosauria,early-diverging Ornithopoda,Hadrosauridae,Titanosauria,and Theropoda)have been recovered.All come from Upper Cretaceous(Coniacian–Maastrichtian)marine and nearshore deposits belonging to the Gustav and Marambio groups of the James Ross Basin at the northern tip of the Antarctic Peninsula.The majority of these finds have come from the Campanian–Maastrichtian Snow Hill Island and López de Bertodano formations of James Ross and Vega islands.Given the rarity of Antarctic Cretaceous non-avian dinosaurs,discoveries of any fossils of these archosaurs,no matter how meager,are of significance.Here we describe fragmentary new ornithischian(ankylosaur and ornithopod)material from the upper Campanian–lower Maastrichtian Cape Lamb Member of the Snow Hill Island Formation and the Maastrichtian Sandwich Bluff Member of the López de Bertodano Formation.One of these specimens is considered to probably pertain to the holotypic individual of the early-diverging ornithopod Morrosaurus antarcticus.We also provide an up-to-date synthesis of the Late Cretaceous non-avian dinosaur record of the James Ross Basin and analyze the biostratigraphic occurrences of the various finds,demonstrating that most(including all named taxa and all reasonably complete skeletons discovered to date)occur within a relatively condensed temporal interval of the late Campanian to early Maastrichtian.Most or all James Ross Basin dinosaurs share close affinities with penecontemporaneous taxa from Patagonia,indicating that at least some continental vertebrates could disperse between southern South America and Antarctica during the final stages of the Mesozoic. 展开更多
关键词 Dinosauria ANTARCTICA Cretaceous JAMES ROSS BASIN BIOSTRATIGRAPHY PALEOBIOGEOGRAPHY
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The enhanced X-ray Timing and Polarimetry mission eXTP
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作者 ShuangNan Zhang Andrea Santangelo +112 位作者 Marco Feroci YuPeng Xu FangJun Lu Yong Chen Hua Feng Shu Zhang S?ren Brandt Margarita Hernanz Luca Baldini Enrico Bozzo Riccardo Campana Alessandra De Rosa YongWei Dong Yuri Evangelista Vladimir Karas Norbert Meidinger Aline Meuris Kirpal Nandra Teng Pan Giovanni Pareschi Piotr Orleanski QiuShi Huang Stephane Schanne Giorgia Sironi Daniele Spiga Jiri Svoboda Gianpiero Tagliaferri Christoph Tenzer Andrea Vacchi Silvia Zane Dave Walton ZhanShan Wang Berend Winter Xin Wu Jean J. M. in 't Zand Mahdi Ahangarianabhari Giovanni Ambrosi Filippo Ambrosino Marco Barbera Stefano Basso Jorn Bayer Ronaldo Bellazzini Pierluigi Bellutti Bruna Bertucci Giuseppe Bertuccio Giacomo Borghi XueLei Cao Franck Cadoux Francesco Ceraudo TianXiang Chen YuPeng Chen Jerome Chevenez Marta Civitani Wei Cui WeiWei Cui Thomas Dauser Ettore Del Monte Sergio Di Cosimo Sebastian Diebold Victor Doroshenko Michal Dovciak YuanYuan Du Lorenzo Ducci QingMei Fan Yannick Favre Fabio Fuschino José Luis Gálvez Min Gao MingYu Ge Olivier Gevin Marco Grassi QuanYing Gu YuDong Gu DaWei Han Bin Hong Wei Hu Long Ji ShuMei Jia WeiChun Jiang Thomas Kennedy Ingo Kreykenbohm Irfan Kuvvetli Claudio Labanti Luca Latronico Gang Li MaoShun Li Xian Li Wei Li ZhengWei Li Olivier Limousin HongWei Liu XiaoJing Liu Bo Lu Tao Luo Daniele Macera Piero Malcovati Adrian Martindale Malgorzata Michalska Bin Meng Massimo Minuti Alfredo Morbidini Fabio Muleri Stephane Paltani Emanuele Perinati Antonino Picciotto Claudio Piemonte JinLu Qu Alexandre Rachevski Irina Rashevskaya Jerome Rodriguez Thomas Schanz ZhengXiang Shen LiZhi Sheng 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第2期3-27,共25页
In this paper we present the enhanced X-ray Timing and Polarimetry mission----eXTP,eXTP is a space science mission designed to study fundamental physics under extreme conditions of density,gravity and magnetism.The mi... In this paper we present the enhanced X-ray Timing and Polarimetry mission----eXTP,eXTP is a space science mission designed to study fundamental physics under extreme conditions of density,gravity and magnetism.The mission aims at determining the equation of state of matter at supra-nuclear density,measuring effects of QED,and understanding the dynamics of matter in strong-field gravity.In addition to investigating fundamental physics,eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects.In particular,its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources. The paper provides a detailed description of:(1)the technological and technical aspects,and the expected performance of the instruments of the scientific payload;(2)the elements and functions of the mission,from the spacecraft to the ground segment. 展开更多
关键词 X-RAY INSTRUMENTATION X-RAY POLARIMETRY X-RAY TIMING space mission:eXTP
Inhibition of immune checkpoints prevents injury-induced heterotopic ossification 预览
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作者 Chen Kan Jiazhao Yang +9 位作者 Ding Na Yuanhong Xu Baixia Yang Haodong Zhao Huadong Lu Yuyun Li Keqin Zhang Tammy LMcGuire John AKessler Lixin Kan 《骨研究:英文版》 SCIE CAS CSCD 2019年第4期437-444,共8页
Heterotopic ossification(HO),true bone formation in soft tissue,is closely associated with abnormal injury/immune responses.We hypothesized that a key underlying mechanism of HO might be injury-induced dysregulation o... Heterotopic ossification(HO),true bone formation in soft tissue,is closely associated with abnormal injury/immune responses.We hypothesized that a key underlying mechanism of HO might be injury-induced dysregulation of immune checkpoint proteins(ICs).We found that the earliest stages of HO are characterized by enhanced infiltration of polarized macrophages into sites of minor injuries in an animal model of HO.The non-specific immune suppressants,Rapamycin and Ebselen,prevented HO providing evidence of the central role of the immune responses.We examined the expression pattern of ICs and found that they are dysregulated in HO lesions.More importantly,loss of function of inhibitory ICs(including PD1,PD-L1,and CD152)markedly inhibited HO,whereas loss of function of stimulatory ICs(including CD40L and OX-40L)facilitated HO.These findings suggest that IC inhibitors may provide a therapeutic approach to prevent or limit the extent of HO. 展开更多
关键词 PD1 INJURIES inhibited
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The circadian clock contributes to diurnal patterns of plant indirect defense in nature
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作者 Youngsung Joo Jay K.Goldberg +3 位作者 Lucille T.S.Chretien Sang-Gyu Kim Ian T.Baldwin Meredith C.Schuman 《植物学报:英文版》 SCIE CAS CSCD 2019年第8期924-928,共5页
The plant circadian clock regulates the rhythms of plant metabolism.Many herbivore-induced plant volatiles(HIPVs)fluctuate,diurnally,but the role of the circadian clock in the emission of HIPVs and their ecological co... The plant circadian clock regulates the rhythms of plant metabolism.Many herbivore-induced plant volatiles(HIPVs)fluctuate,diurnally,but the role of the circadian clock in the emission of HIPVs and their ecological consequences remains largely unknown.Here,we show that the timing of herbivore attack can alter the outcome of tri-trophic interactions,and this is mediated by the circadian clock,under both field and glasshouse conditions.Although most HIPV emissions did not have a circadian rhythm,the circadian clock modulated HIPV emissions in a time-dependent manner.HIPVs mediate tri-trophic interactions,and the circadian clock may affect these interactions by modulating HIPV emission in nature. 展开更多
关键词 HERBIVORE GLASSHOUSE CIRCADIAN RHYTHM
Coping Strategies Adopted by Construction Employees to Deal with the Causes and Effects of Occupational Psychological Disorders: A Study in Ghana 预览
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作者 Genevieve Ataa Fordjour Albert P. C. Chan +1 位作者 Peter Amoah Louis Tuffour-Kwarteng 《健康(英文)》 2019年第6期755-782,共28页
Coping strategies adopted to deal with psychological health issues could have influences on the general health, productivity and task performance of the employee. This study sought to investigate the coping strategies... Coping strategies adopted to deal with psychological health issues could have influences on the general health, productivity and task performance of the employee. This study sought to investigate the coping strategies adopted by construction employees to deal with the causes and effects of occupational psychological disorders such as burnout and workaholism. To achieve this aim, the methods of focus group discussions were first employed. A total of 16 semi-structured focus group discussions were held in Ghana, with 90 construction employees. The focus group study revealed 25 coping strategies adopted as efforts to mitigate the causes and 22 coping strategies adopted as responses to moderate the effects of occupational psychological disorders. A quantitative study involving 150 construction professionals and 150 construction trade workers were also conducted in Ghana to investigate the coping strategies that were highly adopted by the two construction working groups. The findings from the study revealed that the construction professionals adopted delegating complicated tasks and seeking medical attention as the most common coping strategies to manage the causes and effects respectively. The construction trade workers were also revealed to adopt withdrawing from work duties or changing jobs and taking in more caffeinated drinks as the most common coping strategies to manage the causes and effects respectively. Exploratory factor analysis was employed, and the findings were put into the main constructs. The causes focused coping strategies were categorized under avoidance, alteration, adaptation, and acceptance. The effects focused coping strategies were also categorized under healthy and unhealthy coping strategies. This study recommends appropriate coping strategies and interventions in the construction industry such as education of construction personnel on the consequences of various coping strategies. 展开更多
关键词 OCCUPATIONAL PSYCHOLOGY Psychological Disorders COPING Strategies CONSTRUCTION EMPLOYEES Ghana
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Influence of polyolefin fibers on the strength and deformability properties of road pavement concrete
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作者 Olga Smirnova Alexey Kharitonov Yuriy Belentsov 《交通运输工程学报(英文版)》 CSCD 2019年第4期407-417,共11页
Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson... Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the paper.The ways of fibers introduction into fresh concrete were investigated. It was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m~3 was 23% and 29%;for macrofibers in quantity of 3 kg/m~3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete. 展开更多
关键词 Road PAVEMENT CONCRETE POLYOLEFIN fibers STRENGTH Elastic MODULUS Abrasion Water-to-cement ratio
5D Model Theory for the Creating of Life Forms 预览
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作者 K. W. Wong Peter C. W. Fung W. K. Chow 《现代物理(英文)》 2019年第13期1548-1565,共18页
Based on the Fermat’s Last Theorem and the Po, P1 projections from the 4th space coordinate to the time variable for Po and to the remaining 3D space variables for P1, the carbon 12 nucleus is shown explicitly as giv... Based on the Fermat’s Last Theorem and the Po, P1 projections from the 4th space coordinate to the time variable for Po and to the remaining 3D space variables for P1, the carbon 12 nucleus is shown explicitly as given by the hard-sphere dense packing model that also satisfies the Gell-Mann standard model. It is through these that C12 is a vital element in all biomaterials, and all proteins as well as the Nitrogenous bases in DNAs, are of hexagon geometric structures. Furthermore, the unique presence of a 3D × 1D space void within the C12 nucleus provides for the monopole Boson field tunneling to occur, giving rise to the enormous variety spectra in the DNA of life forms. In addition, on the surface of the bio cells, the carbon valence band p electron excitation into the empty conduction band separated by a bandgap G, can result in HTC Excitonic induced superconductivity binding gaps from the Excitonic spectra, which match part of those of the DNA and thus produce the self-grow mechanism of numerous different cells in a life form. 展开更多
关键词 5D PROJECTION Nitrogenous BASES DNA SPECTRA Cell Growth GENOME Protein Effect Excitonic SUPERCONDUCTIVITY in Cells FRACTAL Hexagon Carbon Representation
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To compute or not to compute?
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作者 Alessandra Fiore Ivo Vanzi +3 位作者 Camillo Nuti Cristoforo Demartino Rita Greco Bruno Briseghella 《交通运输工程学报(英文版)》 CSCD 2019年第1期85-93,共9页
In a previous paper “to retrofit or not to retrofit?'(Nuti and Vanzi, 2003) a straightforward procedure able to forecast the economic return of seismic structural upgrading was presented. More recently, the autho... In a previous paper “to retrofit or not to retrofit?'(Nuti and Vanzi, 2003) a straightforward procedure able to forecast the economic return of seismic structural upgrading was presented. More recently, the authors realized that the final mathematical results can be much simplified so as to allow back-of-an-envelope computation. The title of this paper tries to highlight precisely this aspect, namely that for many a regular seismic structural upgrading cases, nearly no computation is needed(apart from one subtraction and one multiplication) to assess their economic convenience. These findings are presented and discussed in this paper, together with a state of the art on the cost-studies available in literature and technical codes. The mathematical formulation leading to the proposed approximation is suitably explained, underlining its applicability field and comparing it with the rigorous solution. Also a table and a formula are furnished that alternatively allows to calculate the maximum estimation errors, in order to obtain an upper and lower bound for the maximum amount of money which should be allocated for seismic structural upgrading. 展开更多
关键词 SEISMIC retrofitting STRUCTURAL RELIABILITY Safety OPTIMIZATION COST MINIMIZATION
Identification of anticancer drugs to radiosensitise BRAF-wild-type and mutant colorectal cancer 预览
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作者 Rebecca Carter Azadeh Cheraghchi-Bashi +11 位作者 Adam Westhorpe Sheng Yu Yasmin Shanneik Elena Seraia Djamila Ouaret Yasuhiro Inoue Catherine Koch Jenny Wilding Daniel Ebner Anderson J. Ryan Francesca M. Buffa Ricky A. Sharma 《癌症生物学与医学:英文版》 CAS CSCD 2019年第2期234-246,共13页
Objective: Patients with BRAF-mutant colorectal cancer(CRC) have a poor prognosis. Molecular status is not currently used to select which drug to use in combination with radiotherapy. Our aim was to identify drugs tha... Objective: Patients with BRAF-mutant colorectal cancer(CRC) have a poor prognosis. Molecular status is not currently used to select which drug to use in combination with radiotherapy. Our aim was to identify drugs that radiosensitise CRC cells with known BRAF status.Methods: We screened 298 oncological drugs with and without ionising radiation in colorectal cancer cells isogenic for BRAF. Hits from rank product analysis were validated in a 16-cell line panel of human CRC cell lines, using clonogenic survival assays and xenograft models in vivo.Results: Most consistently identified hits were drugs targeting cell growth/proliferation or DNA damage repair. The most effective class of drugs that radiosensitised wild-type and mutant cell lines was PARP inhibitors. In clonogenic survival assays, talazoparib produced a radiation enhancement ratio of 1.9 in DLD1(BRAF-wildtype) cells and 1.8 in RKO(BRAF V600 E) cells. In DLD1 xenografts, talazoparib significantly increased the inhibitory effect of radiation on tumour growth(P ≤ 0.01).Conclusions: Our method for screening large drug libraries for radiosensitisation has identified PARP inhibitors as promising radiosensitisers of colorectal cancer cells with wild-type and mutant BRAF backgrounds. 展开更多
关键词 RADIOSENSITIZER colorectal cancer PARP inhibitor RADIOTHERAPY
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Prediction of spatial soil loss impacted by long-term land-use/land-cover change in a tropical watershed 预览
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作者 J.H.Abdulkareem B.Pradhan +1 位作者 W.N.A.Sulaiman N.R.Jamil 《地学前缘:英文版》 CAS CSCD 2019年第2期389-403,共15页
The devastating effect of soil erosion is one of the major sources of land degradation that affects human lives in many ways which occur mainly due to deforestation,poor agricultural practices,overgrazing,wildfire and... The devastating effect of soil erosion is one of the major sources of land degradation that affects human lives in many ways which occur mainly due to deforestation,poor agricultural practices,overgrazing,wildfire and urbanization.Soil erosion often leads to soil truncation,loss of fertility,slope instability,etc.which causes irreversible effects on the poorly renewable soil resource.In view of this,a study was conducted in Kelantan River basin to predict soil loss as influenced by long-term land use/land-cover(LULC)changes in the area.The study was conducted with the aim of predicting and assessing soil erosion as it is influenced by long-term LULC changes.The 13,100 km^2 watershed was delineated into four sub-catchments Galas,Pergau,Lebir and Nenggiri for precise result estimation and ease of execution.GIS-based Universal Soil Loss Equation(USLE)model was used to predict soil loss in this study.The model inputs used for the temporal and spatial calculation of soil erosion include rainfall erosivity factor,topographic factor,land cover and management factor as well as erodibility factor.The results showed that 67.54%of soil loss is located under low erosion potential(reversible soil loss)or 0e1 t ha^-1 yr^-1 soil loss in Galas,59.17%in Pergau,53.32%in Lebir and 56.76%in Nenggiri all under the 2013 LULC condition.Results from the correlation of soil erosion rates with LULC changes indicated that cleared land in all the four catchments and under all LULC conditions(1984-2013)appears to be the dominant with the highest erosion losses.Similarly,grassland and forest were also observed to regulate erosion rates in the area.This is because the vegetation cover provided by these LULC types protects the soil from direct impact of rain drops which invariably reduce soil loss to the barest minimum.Overall,it was concluded that the results have shown the significance of LULC in the control of erosion.Maps generated from the study may be useful to planners and land use managers to take appropriate decisions for soil conserva 展开更多
关键词 Soil EROSION USLE Landuse/cover changes GIS MALAYSIA
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A Proposed Knowledge Management Implementation Framework for the Ghanaian Construction Industry 预览
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作者 Francis Lanme Guribie Callistus Tengan 《房屋建造与规划研究(英文)》 2019年第1期1-10,共10页
This study aims at developing a Knowledge Management Implementation Framework for adoption by firms in the Ghanaian construction industry. Recent developments in the field of Knowledge management in the construction s... This study aims at developing a Knowledge Management Implementation Framework for adoption by firms in the Ghanaian construction industry. Recent developments in the field of Knowledge management in the construction sector have led to a renewed competition in driving organizational performance. However, the construction industry in Ghana lacks a knowledge management implementation framework that addresses the needs of the Ghanaian construction supply chain while a comprehensive approach to managing knowledge remains nebulous. The study adopted an extensive literature review of existing knowledge management models to provide the basis for the development of the proposed framework for Ghana. The proposed knowledge management implementation framework was subjected to testing and validation by project managers drawn from nineteen indigenous construction firms in Ghana. The technology acceptance model (TAM) was used as the criteria to validate the proposed knowledge management implementation framework. The proposed Guribie & Tengan knowledge management implementation framework was perceived to be useful, and easy to use and the intention to adopt and use was high among indigenous Ghanaian construction firms. The study recommends further validation using wider population to enhance the efficacy of the framework for wider industry acceptance to enhance organizational competitiveness and performance delivery. 展开更多
关键词 Construction Ghana IMPLEMENTATION FRAMEWORK KNOWLEDGE Management Technology ACCEPTANCE Model (TAM)
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Analyzing construction safety through time series methods
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作者 Houchen CAO Yang Miang GOH 《工程管理前沿:英文版》 2019年第2期262-274,共13页
The construction industry produces a large amount of data on a daily basis. However, existing data sets have not been fully exploited in analyzing the safety factors of construction projects. Thus, this work describes... The construction industry produces a large amount of data on a daily basis. However, existing data sets have not been fully exploited in analyzing the safety factors of construction projects. Thus, this work describes how temporal analysis techniques can be applied to improve the safety management of construction data. Various time series (TS) methods were adopted for identifying the leading indicators or predictors of construction accidents. The data set used herein was obtained from a large construction company that is based in Singapore and contains safety inspection scores, accident cases, and project-related data collected from 2008 to 2015. Five projects with complete and sufficient data for temporal analysis were selected from the data set. The filtered data set contained 23 potential leading indicators (predictors or input variables) of accidents (output or dependent variable). TS analyses were used to identify suitable accident predictors for each of the five projects. Subsequently, the selected input variables were used to develop three different TS models for predicting accident occurrences, and the vector error correction model was found to be the best model. It had the lowest root mean squared error value for three of the five projects analyzed. This study provides insights into how construction companies can utilize TS data analysis to identify projects with high risk of accidents. 展开更多
关键词 time series TEMPORAL construction safety LEADING INDICATORS ACCIDENT PREVENTION forecasting
Potential strategies offered by animals to implement in buildings' energy performance: Theory and practice
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作者 Cesar Martin-Gomez Amaia Zuazua-Ros +3 位作者 Javier Bermejo-Busto Enrique Baquero Rafael Miranda Cristina Sanz 《建筑学研究前沿(英文版)》 CSCD 2019年第1期17-31,共15页
The strategies for thermal regulation and envir on mental control found in nature are countless. In this article, a parallelism between animals and building energy systems is defined in order to identJfy and emphasize... The strategies for thermal regulation and envir on mental control found in nature are countless. In this article, a parallelism between animals and building energy systems is defined in order to identJfy and emphasize the immediate opportunities that biomimicry offers for future research. The motivation was the need to find alternative solutions to tackle problems mainly in the efficiency of heating, ventilation and cooling systems. Due to the wide range of possibilities offered by animals, this study is largely limited to the strategies that cold-blooded animals have developed through evolutionary adaptation to the environment. The method used for the an a lysis is based on a soluti on-based approach. Firstly, differe nt animal thermoregulation strategies are defined (biological domain). Then the strategy is an a lyzed and classified into three categories. This classification is esse ntial in order to formulate the parallelism with building systems (transfer phase). The final step is to identify the potential implementation (technological domain).This approach has been seen to be useful in creating new research opportunities based on biomimicry. In addition, suitable solutions arising from multidisciplinary team research are presented as promising answers to the challenges that building energy systems face no wadays. 展开更多
关键词 Biomimicry Building SERVICES Energy systems PASSIVE design MULTIDISCIPLINARY
Exploring Personal Factors That Might Influence the Vulnerability of Construction Employees to Occupational Psychological Disorders 预览
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作者 Genevieve Ataa Fordjour Albert P. C. Chan Peter Amoah 《健康(英文)》 2019年第5期546-566,共21页
Personal factors could act as intervening variables between the causes and effects of psychological health conditions of employees. This study focused on six personal intervening factors that were associated with the ... Personal factors could act as intervening variables between the causes and effects of psychological health conditions of employees. This study focused on six personal intervening factors that were associated with the risks of occupational psychological disorders namely: low self-esteem, negative personality trait, unproductive core beliefs, poor self-concept evaluation on performance, poor relationship with others and poor time management skills. An investigation on the level of severity of these personal intervening factors was conducted involving 150 construction professionals and 150 construction trade workers, who were purposively selected in Ghana. The personal factors that were found to be prevalent among the construction employees were low self-esteem and poor time management skills. Correlation analysis and regression analysis were used to determine the relationships between the personal intervening factors and demographic factors such as the age, educational levels and marital status of the research participants. The results of the study indicated that the age and marital status of the respondents had no significant relationship with any of the personal intervening factors. Personal factors such as personality trait and relationship with others also had no relation with any of the demographic factors analyzed. The educational level of the respondents, however, had a significant relationship with the factors of self-esteem, productive core beliefs, self-evaluation on performance and time management skills. An independent two-sample T-test was used to compare the means of the factors with significant relations. This study revealed that construction employees who were highly educated had better self-esteem and time management skills than those who were less educated. The findings from this study broaden the view of moderators on influential sources of psychological health conditions of employees. 展开更多
关键词 OCCUPATIONAL PSYCHOLOGY PSYCHOLOGICAL Disorders Personal Factors CONSTRUCTION EMPLOYEES Ghanaian CONSTRUCTION
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A Quantum Representation of the Homogeneous 5D Manifold and the Perelman Mappings of 5D onto Non-Homogeneous Lorentz 4D Manifolds 预览
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作者 Kai Wai Wong Peter Chin Wan Fung Wan Ki Chow 《现代物理(英文)》 2019年第5期557-575,共19页
The expression of the Maxwell magnetic monopole was employed to correlate the space to space projection that gives rise to the Gell-Mann standard model, and space to time projection which gives the leptons;and how doe... The expression of the Maxwell magnetic monopole was employed to correlate the space to space projection that gives rise to the Gell-Mann standard model, and space to time projection which gives the leptons;and how does it correlate to the Perelman mappings from the homogeneous 5D manifold to the Lorentz 4D manifold, together with correlating the physical consequences caused by the breaking of the Diagonal Long Range Order [DLRO] of the monopoles quantum states affected by the motion of massive particles in the Lorentz 4D boundary of the 5D manifold, which leads to gravitons and the gravity field via the General Relativity covariant Riemannian 4D curvatures metric equation. 展开更多
关键词 5D HOMOGENEOUS MANIFOLD Perelman MAPPINGS Magnetic MONOPOLES Space Projections and Topological Symmetries COVARIANT RIEMANNIAN Curvature and Gravity
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Developing Suitable Proportions for the Production of Pineapple Leaf Fibers Reinforced Normal Strength Concrete 预览
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作者 Kayibanda Patrick Richard Ocharo Onchiri Geoffrey N. Mang’uriu 《土木工程期刊(英文)》 2019年第3期185-194,共10页
The present work tried to develop suitable proportions for the production of Pineapple Leaf Fibers (PALF) reinforced Normal Strength Concrete (NSC), an experimental analysis with a mix ratio of 1:1.84:3.27 for cement:... The present work tried to develop suitable proportions for the production of Pineapple Leaf Fibers (PALF) reinforced Normal Strength Concrete (NSC), an experimental analysis with a mix ratio of 1:1.84:3.27 for cement: fine aggregates: coarse aggregates with constant water to cement ratio of 0.54. The total volume per mixing batch was calculated of 9 cubes + 9 cylinders + 3 beams in order to know the number of materials to be used in casting per batch, and the PALF percentage was taken based on cement weight whereby it starts from the lowest to the maximum as follow 0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1%. The tests that were done on fresh concrete were compacting factors and workability using the slump test which was carried out on each fresh mix of concrete. The results showed that PALF can be used to improve the Tensile and Flexural properties of Normal Strength Concrete. 展开更多
关键词 PINEAPPLE Leaf Fibers TENSILE STRENGTH COMPRESSIVE STRENGTH FLEXURAL STRENGTH and Water Absorption
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MapMan4: A Refined Protein Classification and Annotation Framework Applicable to Multi-Omics Data Analysis
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作者 Rainer Schwacke Gabriel Y.Ponce-Soto +7 位作者 Kirsten Krause Anthony M.Bolger Borjana Arsova Asis Hallab Kristina Gruden Mark Stitt Marie E.Bolger Bjorn Usadel 《分子植物:英文版》 SCIE CAS CSCD 2019年第6期879-892,共14页
Genome sequences from over 200 plant species have already been published, with this number expected to increase rapidly due to advances in sequencing technologies. Once a new genome has been assembled and the genes id... Genome sequences from over 200 plant species have already been published, with this number expected to increase rapidly due to advances in sequencing technologies. Once a new genome has been assembled and the genes identified, the functional annotation of their putative translational products, proteins, using ontologies is of key importance as it places the sequencing data in a biological context. Furthermore, to keep pace with rapid production of genome sequences, this functional annotation process must be fully automated. Here we present a redesigned and significantly enhanced MapMan4 framework, together with a revised version of the associated online Mercator annotation tool. Compared with the original MapMan, the new ontology has been expanded almost threefold and enforces stricter assignment rules. This framework was then incorporated into Mercator4, which has been upgraded to reflect current knowledge across the land plant group, providing protein annotations for all embryophytes with a comparably high quality. The annotation process has been optimized to allow a plant genome to be annotated in a matter of minutes. The output results continue to be compatible with the established MapMan desktop application. 展开更多
关键词 Plant GENOMES Functional ANNOTATION MapMan Mercator TRANSCRIPTOMES
The Impact of Marine Water on Different Types of Coarse Aggregate of Geopolymer Concrete 预览
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作者 Shimaa Younis Megahed Abolwafa Mohamad Elthakeb +2 位作者 Walid Alsayed Mohamed Mohammed Taha Nooman Walid Hessian Soufy 《矿物质和材料特性和工程(英文)》 2019年第5期330-353,共24页
This research studies the impact of different types of coarse aggregate on the behavior of geopolymer concrete based on both fly ash (FA) and ground granulated blast furnace slag (GGBFS) in different marine environmen... This research studies the impact of different types of coarse aggregate on the behavior of geopolymer concrete based on both fly ash (FA) and ground granulated blast furnace slag (GGBFS) in different marine environments. Aiming to solve the problems caused by the construction and demolition waste and the depletion of natural aggregates, in the present study coarse recycled aggregates is used to produce new green concrete with a fly ash-slag based geopolymer. By this examination, the research seeks to improve the quality and productivity of concrete used in construction and hydraulic projects. For this research, four mixtures containing different types of coarse aggregate in two different water environments were used. The utilized mixtures contained natural aggregate concrete (NAC) such as basalt and crushed marble. Also, recycled coarse aggregate concrete (RAC), which totally replaced natural aggregate, was presented in this paper such as crushed concrete and crushed ceramic. For this study, in the sieve analysis;specific and unit weights, was recorded. Furthermore, the mechanical properties were determined, using a compressive test that was conducted on the 7th, 28th, 56th and 90th days at different water environments;potable water (PW) and sea water (SW). Durability test was also performed for total absorption measurement. Results indicated that geopolymer concrete exhibits better strength in marine environments than in those of potable water. Results also showed that crushed marble (CMA) exhibits higher compressive strength and durability. 展开更多
关键词 GEOPOLYMER CONCRETE FLY Ash Ground Granulated Blast FURNACE Slag (GGBFS) Sea WATER Natural AGGREGATE CONCRETE Recycled CONCRETE AGGREGATE Compressive Strength and Durability
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Burnout in the emergency department:Randomized controlled trial of an attention-based training program
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作者 Pádraic J. Dunne Julie Lynch +10 位作者 Lucia Prihodova Caoimhe Oleary Atiyeh Ghoreyshi Sharee A. Basdeo Donal J. Cox Rachel Breen Ali Sheikhi Aine Carroll Cathal Walsh Geraldine McMahon Barry White 《结合医学学报:英文版》 CAS CSCD 2019年第3期173-180,共8页
Background:Burnout(encompassing emotional exhaustion,depersonalization and personal accomplishment)in healthcare professionals is a major issue worldwide.Emergency medicine physicians are particularly affected,potenti... Background:Burnout(encompassing emotional exhaustion,depersonalization and personal accomplishment)in healthcare professionals is a major issue worldwide.Emergency medicine physicians are particularly affected,potentially impacting on quality of care and attrition from the specialty.Objective:The aim of this study was to apply an attention-based training(ABT)program to reduce burnout among emergency multidisciplinary team(MDT)members from a large urban hospital.Design,setting,participants and interventions:Emergency MDT members were randomized to either a notreatment control or an in terve ntion group.In tervention group participa nts engaged in a four sessi on(4 h/sessi on)ABT program over 7 weeks with a practice target of 20 min twice-daily.Practice adhere nee was measured using a smart phone application together with a wearable Charge 2 device.Main outcome measures:The primary outcome was a change in burnout,comprising emotional exhaustion,depersonalization and personal achieveme nt.The sec on dary outcomes were cha nges in other psychological and biometric parameters.Results:The ABT program resulted in a significant reduction(P<0.05;T1|one week before intervention]vs T3[follow-up at two mon ths after intervention])in burnout,specifically,emotional exhaustion,with an effect size(probability of superiority)of 59%.Similar reductions were observed for stress(P<0.05)and anxiety(P<0.05).Furthermore,ABT group participants demonstrated significant improvements in heart rate variability,resting heart rate,sleep as well as an in crease in pro-inflammatory cytokine expression.Conclusion:This study describes a positive impact of ABT on emergency department staff bumout compared to a no-treatment control group.Trial registration:ClinicalTrials.gov identifier NCT02887300. 展开更多
关键词 BURNOUT EMOTIONAL EXHAUSTION MEDITATION Healthcare professional Sleep Stress Cytokines CORTISOL Randomized controlled trial
Review on nanocomposites fabricated by mechanical alloying 预览
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作者 Mohammed A. Taha Rasha A. Youness M.F. Zawrah 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第9期1047-1058,共12页
Composites are composed of multiphase materials, where each phase has specific properties that differ from those of the other phases which can effect on the whole properties of composite. Nanocomposites are class of m... Composites are composed of multiphase materials, where each phase has specific properties that differ from those of the other phases which can effect on the whole properties of composite. Nanocomposites are class of materials that contain at least one phase in the nanometric size range and can be produced by any suitable technique for preparing nanomaterials. Composites are an interesting class of materials that have recently been used in numerous applications, including structural, biomedical, electronics, and environmental applications. In composites, reinforcements might be fibers, particulates, or whiskers. Mechanical alloying(MA) is a promising technique for producing nanocomposite materials that are difficult or impossible to prepare via conventional techniques. In this review, we provide an overview of nanocomposites prepared by the MA process. The mechanism of milling and other milling parameters are overviewed, and insights into sintering categories and parameters are also presented. 展开更多
关键词 NANOCOMPOSITES mechanical ALLOYING FABRICATION SINTERING
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