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Pedosphere 2021年第2期31卷 342-352页

作者： Emma m.DOCHERTY Andrew D.THOmAS Department of Geography and Earth Sciences Aberystwyth UniversityAberystwyth SY233DB(UK) School of Geography University of LeedsLeeds LS29JT(UK)

Seasonally flooded várzea forests of Western Amazonia are one of the most productive and biodiverse wetland forests in the ***,data on their soil CO_(2)emissions,soil organic matter decomposition rates,and soil C stocks are *** is a concern because hydrological changes are predicted to lead to increases in the height,extent,and duration of seasonal floods,which are likely to have a significant effect on soil C stocks and ***,with no empirical data,the impact of altered flood regimes on várzea soil C cycles remains *** study quantified the effects of maximum annual flood height and soil moisture on soil CO_(2)efflux rate(R_(s))and soil organic matter decomposition rate(k)in the várzea forests of Pacaya Samiria National Reserve,*** study was conducted between may and August *** results showed that R_(s)(10.6–182.7 mg C m^(-2)h^(-1))and k(0.016–0.078)varied between and within sites,and were considerably lower than the values reported for other tropical *** addition,R_(s)was negatively affected by flood height(Pmoisture(Pmentioned *** moisture was the dominant factor influencing R_(s),and it was significantly affected by maximum flood height,even after the floods had subsided(Pmain unchanged but with decomposition processes becoming more anaerobic.

关键词： C cycle climate change greenhouse gas soil CO_(2)emissions soil moisture soil organic matter decomposition rate tropical forest

Al–TiO_2–Gr powder metallurgy hybrid composites with cold upset forging

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Rare metals 2014年第6期33卷 686-696页

作者： m.Ravichandran A.Naveen Sait V.Anandakrishnan Department of mechanical Engineering Chendhuran College of Engineering and Technology Department of Production Engineering National Institute of Technology

The cold upsetting studies were carried out for the aluminium metal matrix hybrid composites in the present study. Aluminium metal matrix hybrid composites were synthesised through powder metallurgy route from ball-milled powders to yield the following compositions：Al ＋ 2.5 wt% TiO2＋ 2 wt% Gr, Al ＋ 2.5 wt% TiO2＋ 4 wt% Gr, Al ＋ 5.0 wt% TiO2＋ 2 wt% Gr and Al ＋ 5.0 wt% TiO2＋ 4 wt% Gr. The compaction process was carried out using suitable punch and die in 40 k N hydraulic press, and sintering was done in an electric muffle furnace at the temperature of 590 °C for 3 h. The sintered preforms were subjected to incremental compressive loading of 10 k N until the cracks were found at the free surface. The true axial stress, true hoop stress, true hydrostatic stress and true effective stress were calculated for all the preforms, and all these stresses are correlated with the true axial strain. The stress ratio parameters（rz/reff, rh/reff, rz/rmand rh/rm） of the all preforms were correlated with true axial strain. The maximum true axial stress, true hoop stress, true effective stress and hydrostatic static stress are obtained for the composite containing5 wt% of TiO2 and 4 wt% of graphite and the minimum ones are obtained for composite containing 2.5 wt% of TiO2 and 2 wt% of graphite.

关键词： metal matrix composites Cold upsetting Powder metallurgy

HEALTHCARE: A COmPLEX SERVICE SYSTEm

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Journal of Systems Science and Systems Engineering 2009年第3期18卷 257-282页

作者： James m. TIEN Pascal J. GOLDSCHmIDT-CLERmONT Dean College of Engineering University of Miami Coral GablesFlorida USA Dean Miller School of Medicine University of Miami Coral GablesFlorida USA

Healthcare is indeed a complex service system, one requiring the technobiology approach of systems engineering to underpin its development as an integrated and adaptive system. In general, healthcare services are carried out with knowledge-intensive agents or components which work together as providers and consumers to create or co-produce value. Indeed, the engineering design of a healthcare system must recognize the fact that it is actually a complex integration of human-centered activities that is increasingly dependent on information technology and knowledge. Like any service system, healthcare can be considered to be a combination or recombination of three essential components - people （characterized by behaviors, values, knowledge, etc.）, processes （characterized by collaboration, customization, etc.） and products （characterized by software, hardware, infrastructures, etc.）. Thus, a healthcare system is an integrated and adaptive set of people, processes and products. It is, in essence, a system of systems which objectives are to enhance its efficiency （leading to greater interdependency） and effectiveness （leading to improved health）. Integration occurs over the physical, temporal, organizational and functional dimensions, while adaptation occurs over the monitoring, feedback, cybernetic and learning dimensions. In sum, such service systems as healthcare are indeed complex, especially due to the uncertainties associated with the human-centered aspects of these systems. moreover, the system complexities can only be dealt with methods that enhance system integration and adaptation.

关键词： Services healthcare system integration system adaptation system complexity system of systems customization co-production decision informatics real-time decision making

material Research Related to Structural Pavement Failure on motorway A32 in the Netherlands

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武汉理工大学学报 2010年第17期32卷 8-17页

作者： HOUBEN L J m mOLENAAR A A A ERKENS S m J G Faculty Civil Engineering and Geosciences Delft University of Technology ministry of Traffic Public Works and Water ManagementCentre for Transport and Navigation

In 2008 structural failures occurred on the asphalt pavement,with a hydraulic blast furnace slag base,of the motorway A32 (constructed in 1986～1988) in the Netherlands. Within a few weeks serious depressions occurred,in which the asphalt pavement was full of cracks and the base had a very low stiffness. In 2008 and 2009 the pavement including the base was rehabilitated over a length of 10 *** Dutch ministry of Public Works has initiated an extensive research into the risks of occurrence of this type of unexpected structural damages on the main road network in the Netherlands. Among many other things this research includes material research into the base material of the A32 to find the cause of the structural *** total 130 cores,divided over 26 cross-sections,were drilled from the A32. The cross-sections were divided over 3 areas,with a high and low base stiffness respectively and also at heaves that had grown into the pavement since 1998. In areas with high base stiffness the cores mainly contained bound base material,in areas with low base stiffness mainly granular material and at the heaves it was a mix thereof. Standard (static) and dynamic crushing tests were done on the granular material. Dynamic and monotonic indirect tensile tests and compression tests were performed on the bound material. In all cases no systematic difference was found between the mechanical properties of the blast furnace slag base material from the heavily loaded right traffic lane and the material from the other *** is concluded that the pavement failure on the A32 is introduced by the occurrence of full depth asphalt fatigue cracks in the pavement that was originally designed for 12 years (but was never strengthened) in areas where the base stiffness always has been low or became low through crushing (that also has resulted in the heaves). Penetrated rainwater then has weakened the base and pumping has occurred,resulting into loss of bearing capacity and decrease of vo

关键词： structural failure blast furnace slags base laboratory testing

Exact identities for sessile drops

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Applied mathematics and mechanics(English Edition) 2015年第3期36卷 293-302页

作者： m.HAJIRAHImI F.mOKHTARI A.H.FATOLLAHI Physics Group South Tehran BranchIslamic Azad University Department of Physics Alzahra University

By direct integration of the are presented for the axisymmetric sessile geometrical parameters, including the apex Young-Laplace relation, a set of identities drops on fiat and curved substrates. The curvature, the apex height, and the contact radius, are related by the identities. The validity of the identities is checked by various numerical solutions for drops on flat and curved substrates.

关键词： drop hydrostatics surface tension identity

Effects of variable retention harvesting on canopy transpiration in a red pine plantation forest

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Ecological Processes 2022年第1期11卷 374-385页

作者： Alanna V.Bodo m.Altaf Arain School of Earth Environment and SocietyMcMaster University1280 Main Street WestHamiltonON L8S 4K1Canada mcmaster Centre for Climate Change McMaster University1280 Main Street WestHamiltonON L8S 4K1Canada

Background:Variable Retention Harvesting(VRH)is a forest management practice applied to enhance forest growth,improve biodiversity,preserve ecosystem function and provide economic revenue from harvested *** are many different forms and compositions in which VRH is applied in forest *** this study,the impacts of four different VRH treatments on transpiration were evaluated in an 83-year-old red pine(Pinus Pinus resinosa)plantation forest in the Great Lakes region in *** VRH treatments included 55%aggregated crown retention(55A),55%dispersed crown retention(55D),33%aggregated crown retention(33A),33%dispersed crown retention(33D)and unharvested control(CN)*** VRH treatments were implemented in 1-ha plots in the winter of 2014,while sap flow measurements were conducted from 2018 to ***:Study results showed that tree-level transpiration was highest among trees in the 55D treatment,followed by 33D,55A,33A and CN *** found that photosynthetically active radiation(PAR)and vapor pressure deficit(VPD)were major controls or drivers of transpiration in all VRH *** study suggests that dispersed or distributed retention of 55%basal area(55D)is the ideal forest management technique to enhance transpiration and forest ***:This study will help researchers,forest managers and decision-makers to improve their understanding of water cycling in forest ecosystem and adopt the best forest management regimes to enhance forest growth,health and resiliency to climate change.

关键词： Variable Retention Harvesting Forest management Transpiration Sap flow Red pine Great Lakes region

Chitosan/Nanocrystalline Cellulose Biocomposites Based on Date Palm (Phoenix Dactylifera L.) Sheath Fibers

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Journal of Renewable materials 2019年第6期7卷 567-582页

作者： Abeer m.Adel Amira m.El-Shafei Atef A.Ibrahim mona T.Al-Shemy Cellulose and Paper Department National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt Textile Research Division National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt

In this study,nanocrystalline celluloses were used to enhance physical,mechanical and water vapor barrier properties of chitosan films for potential food packaging *** different mineral acids(sulfuric and phosphoric)were used to extract nanocrystalline cellulose from date palm sheath *** influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses(e.g.,yield,energy and length of intra-and intermolecular hydrogen bonds,and degree of substitution)were studied *** characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline *** showed that besides cellulose polymorphism,the ionic ester groups on the surface of nanocrystalline cellulose is one of the factors influencing the physical,chemical,mechanical,and water vapor barrier properties in chitosan/nanocrystalline cellulose biocomposites.

关键词： Biocomposite Cellulose I Cellulose II Nanocrystalline cellulose(NCC) physico-mechanical properties Thermal stability

Updates in endocrine therapy for metastatic breast cancer

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Cancer Biology & medicine 2022年第2期19卷 202-212页

作者： Poorni m.manohar Nancy E.Davidson University of Washington/Seattle Cancer Care Alliance Seattle 98109WAUSA Fred Hutchinson Cancer Research Center Seattle 98109WAUSA

Endocrine therapy(ET)remains the mainstay of treatment for steroid hormone receptor-positive,human epidermal growth factor 2(HER2)-negative metastatic breast cancer(mBC).Tumor resistance to hormone therapy has led to the development of novel endocrine drug combinations,transforming the landscape of mBC *** options for ET are expanding,with promising agents in the *** mBC remains incurable,many patients can enjoy years of survival with good quality of life by cycling through the many available *** the plethora of available agents and rapid approvals,clinicians look to evidencebased guidelines to assist in treatment selection to maximize patient *** this review,we provide a contemporary review of the advances in ET and a suggested algorithm to guide clinicians in daily management of patients with hormone receptor-positive,HER2-negative *** will discuss landmark trials and highlight their impact in reshaping treatment ***,we will provide a glimpse into advances on the horizon and the promise they bring to improve outcomes in patients with advanced breast cancer.

关键词： Endocrine therapy metastatic breast cancer

Interplay between genome organization and epigenomic alterations of pericentromeric DNA in cancer

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Journal of Genetics and Genomics 2021年第3期48卷 184-197页

作者： Subhadip Kundu m.D.Ray Ashok Sharma Laboratory of Chromatin and Cancer Epigenetics Department of BiochemistryAll India Institute of Medical SciencesAnsari NagarNew Delhi 110029India Department of Surgical Oncology IRCHAll India Institute of Medical SciencesAnsari NagarNew Delhi 110029India

In eukaryotic genome biology,the genomic organization inside the three-dimensional(3D)nucleus is highly complex,and whether this organization governs gene expression is poorly *** lamina(NL)is a filamentous meshwork of proteins present at the lining of inner nuclear membrane that serves as an anchoring platform for genome *** chromatin domains termed as lamina-associated domains(LADs),play a major role in silencing genes at the nuclear *** interaction of the NL and genome is dynamic and ***,many genes change their positions during developmental processes or under disease conditions such as cancer,to activate certain sorts of genes and/or silence *** heterochromatin(PCH)is mostly in the silenced region within the genome,which localizes at the nuclear *** show that several genes located at the PCH are aberrantly expressed in *** interesting question is that despite being localized in the pericentromeric region,how these genes still manage to overcome pericentromeric *** epigenetic mechanisms control the expression of the pericentromeric region,recent studies about genome organization and genome-nuclear lamina interaction have shed light on a new aspect of pericentromeric gene regulation through a complex and coordinated interplay between epigenomic remodeling and genomic organization in Cancer.

关键词： LADs Pericentromere Heterochromatin Gene regulation Epigenetics Cancer Genome organization

Radial variations in xylem sap flux in a temperate red pine plantation forest

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Ecological Processes 2021年第1期10卷 328-336页

作者： Alanna V.Bodo m.Altaf Arain School of Earth Environment and SocietyMcMaster UniversityHamiltonONCanada mcmaster Centre for Climate Change HamiltonONCanada

Background:Scaling sap flux measurements to whole-tree water use or stand-level transpiration is often done using measurements conducted at a single point in the sapwood of the tree and has the potential to cause significant *** studies have shown that much of this uncertainty is related to(i)measurement of sapwood area and(ii)variations in sap flow at different depths within the tree ***:This study measured sap flux density at three depth intervals in the sapwood of 88-year-old red pine(Pinus resinosa)trees to more accurately estimate water-use at the tree-and stand-level in a plantation forest near Lake Erie in Southern Ontario,*** showed that most of the water transport(65%)occurred in the outermost sapwood,while only 26%and 9%of water was transported in the middle and innermost depths of sapwood,***:These results suggest that failing to consider radial variations in sap flux density within trees can lead to an overestimation of transpiration by as much as 81%,which may cause large uncertainties in water budgets at the ecosystem and catchment *** study will help to improve our understanding of water use dynamics and reduce uncertainties in sap flow measurements in the temperate pine forest ecosystems in the Great Lakes region and help in protecting these forests in the face of climate change.

关键词： Sap flow Transpiration Water use Red pine Temperate forest Great Lakes region