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Lipoprotein(a)and Benefit of PCSK9 Inhibition in Emergency Complex Higher-risk and Indicated Patients 被引量:1
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作者 Zhi-li JIN Tao HE +7 位作者 Li PENG Xiao-yan WU Di FAN Ming CHEN Yong-zhen FAN Yuan-lin GUO Zhi-bing LU Hai-rong WANG 《Current Medical Science》 SCIE CAS 2023年第6期1206-1212,共7页
Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially whe... Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially when acute cardiac events occur,such as acute coronary syndrome(ACS)or heart failure.Pharmacotherapy and some mechanical circulatory support(MCS)therapeutic devices can provide stable hemodynamic support for CHIPs-percutaneous coronary intervention(PCI).LDL-C is an important pathogenic factor in atherosclerosis,and the target of blood lipid control.Recent studies have revealed that lipoprotein(a)[Lp(a)],which is formed when a covalent bond between apolipoprotein(a)and apolipoprotein B-100 is made,produces an LDL-like particle.This particle is an independent risk factor for the development of atherosclerosis,and is closely correlated to stent thrombosis and restenosis.Furthermore,this requires active intervention.PCSK9 inhibitors have been used in lipid-lowering treatment,and preventing atherosclerosis.The present study explores the efficacy of PCSK9 inhibitors in CHIPs-ACS,and the association between the change in Lp(a)and survival after 2 years of follow-up.Methods The present real-world,prospective control study enrolled 321 CHIPs-ACS who underwent emergency PCI from August 2019 to November 2020,and these patients were followed up for 2 years.These patients were divided into two groups:PCSK9 group(n=161)given the combined PCSK9 inhibitor(140 mg of evolocumab every 2 weeks)and statins-based therapy,and SOC group(n=160)treated with statin-based lipid-lowering therapy alone.Then,the change in lipid index was measured,and the cardiovascular(CV)event recurrence rate was evaluated after one month and 2 years.Afterwards,the contribution of serum lipid parameters,especially the Lp(a)alteration,in patients with earlier initiation of the PCSK9 inhibitor to the CV outcome was analyzed.Results The LDL-C level was significantly reduced in both groups:52.3%in the PCSK9 group and 32.3%(P<0.001)in the SOC group.It is noteworthy that the Lp(a)level decreased by 13.2%in the PCSK9 group,but increased by 30.3%in the SOC group(P<0.001).Furthermore,the number of CV events was not significantly different between the PCSK9 and SOC groups after the 2-year follow-up period.In the PCSK9 group,the Lp(a)reduction was associated with the baseline Lp(a)levels of the patients(r2=−0.315,P<0.001).Moreover,the decrease in Lp(a)contributed to the decline in CV events in patients who received ACS CHIPs-PCI,and the decrease in Lp(a)level was independent of the LDL-C level reduction.Conclusion The early initiation of PCSK9 inhibitors can significantly reduce the LDL-C and Lp(a)levels in ACS CHIPs-PCI.However,further studies are needed to confirm whether PCSK9 inhibitors can reduce the incidence of CV disease in CHIPs. 展开更多
关键词 PCSK9 inhibitor complex higher-risk and indicated patients lipoprotein(a)level low-density lipoprotein cholesterol level 2-year cardiovascular event rate
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Complementary research in mammals and fish indicates MMP-2 as a pleiotropic contributor to optic nerve regeneration 被引量:3
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作者 Kim Lemmens Inge Van Hove Lieve Moons 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第5期740-742,共3页
Matrix metalloproteinases(MMPs)are members of the metzincin superfamily named after the zinc ion and the conserved methionine residue at the active site.In addition to their role in extracellular matrix(ECM)remode... Matrix metalloproteinases(MMPs)are members of the metzincin superfamily named after the zinc ion and the conserved methionine residue at the active site.In addition to their role in extracellular matrix(ECM)remodeling,these proteinases(in)activate many signaling molecules such as growth factors. 展开更多
关键词 MMP Complementary research in mammals and fish indicates MMP-2 as a pleiotropic contributor to optic nerve regeneration MMPs
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DECADAL CIMATIC VARIATIONS INDICATED BY DULAN TREE RING AND COMPARISON WITH OTHER PROXY DATA IN CHINA OF THE LAST 2000 YEARS
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《Chinese Geographical Science》 SCIE CSCD 2000年第3期2-10,共2页
关键词 Lake DECADAL CIMATIC VARIATIONS indicateD BY DULAN TREE RING AND COMPARISON WITH OTHER PROXY DATA IN CHINA OF THE LAST 2000 YEARS than tree
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Comparison of Perinatal Outcomes in Late Preterm Spontaneous and Indicated Preterm Birth Neonates
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作者 Dasom Chun Eun Hye Yoo +4 位作者 Ji Young Lee Hyun Mi Kim Mi Ju Kim Won Joon Seong Hyun-Hwa Cha 《Open Journal of Obstetrics and Gynecology》 2016年第12期661-668,共8页
Objective: We aimed to compare the perinatal outcomes in late preterm spontaneous and indicated birth neonates. Methods: We studied 289 late preterm births, classified as either aspontaneous late preterm birth (sLPTB)... Objective: We aimed to compare the perinatal outcomes in late preterm spontaneous and indicated birth neonates. Methods: We studied 289 late preterm births, classified as either aspontaneous late preterm birth (sLPTB) group (preterm labor with intact membranes and preterm premature rupture of membranes) or an indicated late preterm birth (iLPTB) group (hypertensive disorder in pregnancy, placental causes, and maternal diseases), according to the delivery indication. We then compared the maternal and neonatal characteristics and perinatal outcomes, including the Apgar score, admission to the neonatal intensive care unit (NICU) or special care nursery (SCN), duration of NICU stay, and the rate of composite morbidity (antibiotic use, hypoglycemia, hypocalcemia, hyperbilirubinemia requiring phototherapy, respiratory support, and respiratory distress syndrome). Results: A total of 198 neonates were in the sLPTB group and 91 were in the iLPTB group. In spite of greater gestational age at the time of delivery in the iLPTB group, the mean birth weight was lower than that in the sLPTB group. Additionally, the iLPTB group showed lower Apgar scores, and higher rates of NICU or SCN admission, respiratory support, and hypoglycemia, but there was no difference in the rate of composite morbidity between the two groups. Conclusion: iLPTB neonates had lower birth weights despite greater gestational age than those in the sLPTB group, but there was no difference in the rate of composite morbidity between the two groups. 展开更多
关键词 Composite Morbidity indicated Preterm Birth Late Preterm Birth Perinatal Outcomes Spontaneous Preterm Birth
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THE SIGNS THAT INDICATE PHYSICAL DECAY IN TIBETAN CULTURE
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作者 THUBEN PHUNTSOG 《China's Tibet》 2007年第2期32-39,共8页
At each and every moment the things of our universe are subject to change. The human body too,from the very moment it is born, begins the process that will ultimately lead to death.
关键词 THE SIGNS THAT indicate PHYSICAL DECAY IN TIBETAN CULTURE
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Industrial Carbon Emission Distribution and Regional Joint Emission Reduction:A Case Study of Cities in the Pearl River Basin,China 被引量:2
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作者 JIANG Hongtao YIN Jian +4 位作者 ZHANG Bin WEI Danqi LUO Xinyuan DING Yi XIA Ruici 《Chinese Geographical Science》 SCIE CSCD 2024年第2期210-229,共20页
China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exi... China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exists an imbalance in the distribution of car-bon emissions.Therefore,regional cooperation serves as an effective means to attain low-carbon development.This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intens-ity(ICEI)as a crucial factor.We utilized social network analysis and Local Indicators of Spatial Association(LISA)space-time trans-ition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin(PRB),China from 2010 to 2020.The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression.The results were as follows:1)the overall ICEI in the Pearl River Basin is showing a downward trend,and there is a significant spatial imbalance.2)There are numerous network connections between cities regarding the ICEI,but the network structure is relatively fragile and unstable.3)Economically developed cities such as Guangzhou,Foshan,and Dongguan are in the center of the network while playing an intermediary role.4)Energy consumption,industrialization,per capita GDP,urbanization,science and techno-logy,and productivity are found to be the most influential variables in the spatial differentiation of ICEI,and their combination in-creased the explanatory power of the geographic variation of ICEI.Finally,through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI,the study suggests joint carbon reduction strategies,which are centered on carbon transfer,financial support,and technological assistance among cities. 展开更多
关键词 industrial carbon emission intensity carbon emission social network analysis Location Indicators of Spatial Association(LISA) geographical detector multi-scale geographically weighted regression Pearl River Basin(PRB) China
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Comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation 被引量:1
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作者 Chuan Li Hong-Xia Chen Yan-Hua Lai 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期143-154,共12页
BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplan... BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplant outcomes.AIM To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation(LT).METHODS A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from December 2019 to June 2022.RESULTS This study identified several independent risk factors associated with 30-d mor-tality,including blood loss,the prognostic nutritional index(PNI),the nutritional risk index(NRI),and the control nutritional status.The 30-d mortality rate was 8.6%.Blood loss,the NRI,and the PNI were found to be independent risk factors for the occurrence of severe postoperative complications.The NRI achieved the highest prediction values for 30-d mortality[area under the curve(AUC)=0.861,P<0.001]and severe complications(AUC=0.643,P=0.011).Compared to those in the high NRI group,the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels,as well as higher alanine aminotransferase and total bilirubin levels,Model for End-stage Liver Disease scores and prothrombin time(P<0.05).Furthermore,the group with a low NRI exhibited significantly greater incidences of intraabdominal bleeding,primary graft nonfunction,and mortality.CONCLUSION The NRI has good predictive value for 30-d mortality and severe complications following LT.The NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy. 展开更多
关键词 Liver transplantation Nutritional indicator COMPLICATIONS PROGNOSIS Nutrition assessment
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Contemporary management of complex higher-risk and indicated patients: perspectives from China 被引量:3
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作者 Hua Shen Yu Du Yu-Jie Zhou 《Chinese Medical Journal》 SCIE CAS CSCD 2019年第12期1387-1389,共3页
Complex higher-risk and indicated patients (CHIPs) refers to patients with severe coronary artery disease (CAD) needing revascularization. However, these patients are at an increased risk for this procedure.[1] The CH... Complex higher-risk and indicated patients (CHIPs) refers to patients with severe coronary artery disease (CAD) needing revascularization. However, these patients are at an increased risk for this procedure.[1] The CHIP population is attracting much interest in the field of interventional cardiology, since it was introduced in 2016 by Kirtane et al,[1] and the optimal treatment strategies for this population were fiercely discussed in almost every interventional forum at home and abroad. First of all, a comprehensive risk assessment must be conducted to determine which patients with CAD should undergo revascularization based on clinical presentation, functional tests, and anatomic characteristics. Percutaneous coronary intervention (PCI) might be a beneficial option when complete revascularization can be achieved, especially for patients are either inoperable or at higher surgical risk.[2,3] To treat these high-risk patients safely and effectively with PCI, well-trained interventionalists exhibiting both technical and cognitive skills are needed. 展开更多
关键词 CONTEMPORARY MANAGEMENT COMPLEX higher-risk indicateD patients
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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture
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作者 Maria Kaleem Erum Bashir +2 位作者 Shahid Naseem Tahir Rafique Bushra Shahab 《Acta Geochimica》 EI CAS CSCD 2024年第2期214-234,共21页
This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by mu... This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical data.The outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the region.Twenty-five soil samples were collected,mainly from the arable land of the Porali Plain.After drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric analysis.Esti-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial distribution.The granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt type.Weathering indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of alteration.These indices reflect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr ratios.Assessment of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the soils.The correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type mineralization.Weathering may result in the undesirable accumulation of certain trace elements which adversely affects crops. 展开更多
关键词 Weathering indices Pollution indices ACCUMULATION Repercussions Trace elements Multivariate analyses Porali Plain BALOCHISTAN
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Community perspectives on the effectiveness of watershed management institutions in the Himalayas
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作者 Nisha SILWAL Nabin DHUNGANA +2 位作者 Rajan SUBEDI Suraj UPADHAYA Chun-Hung LEE 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1119-1139,共21页
The sustainability of environmental management initiatives,such as watershed management programs,relies on the presence of effective institutions at the watershed level.However,there needs to be more empirical evidenc... The sustainability of environmental management initiatives,such as watershed management programs,relies on the presence of effective institutions at the watershed level.However,there needs to be more empirical evidence from evaluating the effectiveness of watershed-level institutions.Therefore,this study presents a pioneering effort to evaluate the effectiveness of Nepal’s first watershed conservation committee at the watershed scale,focusing on the case of the Khageri Khola watershed in Central Nepal.The study involved conducting a household survey,key informant interviews,focus group discussions,and field observations to collect and analyze the data.Descriptive analysis,index value calculation,and chi-square statistics were then employed to summarize the results regarding local respondents’perceptions of twelve institutional characteristics,their rationalities,and their association with socio-demographic variables.The results reveal that the watershed conservation committee was perceived as performing well in managing the watershed.Specifically,good interaction,appropriate scale,technical,environmental,social,organizational,and government rationality were perceived as highly effective,with an average index value of less than 0.36.In contrast,clarity of objectives and economic rationality showed moderate effectiveness,with an average index value ranging from 0.36 to 0.65.However,the results suggested that adaptiveness,compliance capacity,and financial rationality merit increased attention,intending to improve their performance.Further,the results showed the association of socio-demographics with respondents’perceptions of various indicators of institutional characteristics and their rationalities.Therefore,the study provides valuable insights for policymakers,researchers,and development practitioners charged with designing sustainable and effective programs and institutions.To enhance the effectiveness and sustainability of watershed management programs,we recommend establishing a policy-guided institutional mechanism at the watershed scale.This mechanism should be based on various institutional characteristics and rationalities and should consider the extant variability in the socio-demographic and topographic characteristics of the watershed. 展开更多
关键词 WATERSHED Watershed institutions INDICATORS Institutional characteristics Rationalities Nepal.
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Exploring groundwater quality in semi-arid areas of Algeria:Impacts on potable water supply and agricultural sustainability
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作者 Noua ALLAOUA Hinda HAFID Haroun CHENCHOUNI 《Journal of Arid Land》 SCIE CSCD 2024年第2期147-167,共21页
Groundwater quality assessment is important to assure safe and durable water use.In semi-arid areas of Algeria,groundwater represents the main water resource for drinking water supply of the rural population as well a... Groundwater quality assessment is important to assure safe and durable water use.In semi-arid areas of Algeria,groundwater represents the main water resource for drinking water supply of the rural population as well as for irrigation of agricultural lands.Groundwater samples from wells and springs were collected from the Gargaat Tarf and Annk Djemel sub-watersheds of the Oum El Bouaghi,Algeria,and were analyzed and compared with the World Health Organization(WHO)standards.Results showed that most of the measured physical and chemical parameters exceeded the quality limits according to the WHO standards.Groundwater had a slightly alkaline water pH(7.00-7.79),electrical conductivity>1500μS/cm,chloride>500 mg/L,calcium>250 mg/L,and magnesium>155 mg/L.Water quality index(WQI)results showed that 68%of the area had excellent water quality,24%of the samples fell into good category,and only 8%were of poor quality and unsuitable for human consumption.Six wells in the area showed bacterial contamination.Total coliforms(453.9(±180.3)CFU(colony-forming units)/100 mL),fecal coliforms(243.2(±99.2)CFU/100 mL),and fecal streptococci(77.9(±32.0)CFU/100 mL)loads were above the standard limits set by the WHO.These results confirmed that water resources in the study area were strongly influenced by anthropogenic activities and were not recommended for consumption as drinking water. 展开更多
关键词 bacteriological indicator GROUNDWATER WATERSHED physical-chemical parameter water quality index
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Spatio-temporal Variation Characteristics of Extreme Climate Events and Their Teleconnections to Large-scale Ocean-atmospheric Circulation Patterns in Huaihe River Basin,China During 1959–2019
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作者 YAO Tian ZHAO Qiang +6 位作者 WU Chuanhao HU Xiaonong XIA Chuan'an WANG Xuan SANG Guoqiang LIU Jian WANG Haijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期118-134,共17页
Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of... Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB. 展开更多
关键词 extreme climate indices Sen’s slope variation mutation test atmospheric circulation indices Pearson’s correlation analysis Huaihe River Basin(HRB) China
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A review of rock macro-indentation:Theories,experiments,simulations,and applications
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作者 Weiqiang Xie Xiaoli Liu +2 位作者 Xiaoping Zhang Xinmei Yang Xiaoxiong Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2351-2374,共24页
Rock macro-indentation plays a fundamental role in mechanical rock breaking for various rock engineering application,such as drilling,tunneling,cutting,and sawing.Over the past decades,extensive research has been cond... Rock macro-indentation plays a fundamental role in mechanical rock breaking for various rock engineering application,such as drilling,tunneling,cutting,and sawing.Over the past decades,extensive research has been conducted to understand the indentation mechanisms and responses through various approaches.This review aims to provide an overview of the current status and recent advancements in theories,experiments,numerical simulations,and applications of macro-indentation in rock engineering.It starts with elaborating on the mechanisms of macro-indentation,followed by a discussion of the merits and limitations of commonly used models.Influence factors and their effects on indentation test results are then summarized.Various numerical simulation methods for rock macro-indentation are highlighted,along with their advantages and disadvantages.Subsequently,the applications of indentation tests and indentation indices in characterizing rock properties are explored.It reveals that compression-tension,compression-shear,and composite models are widely employed in rock macroindentation.While the compression-tension model is straightforward to use,it may overlook the anisotropic properties of rocks.On the other hand,the composite model provides a more comprehensive description of rock indentation but requires complex calculations.Additionally,factors,such as indentation rate,indenter geometry,rock type,specimen size,and confining pressure,can significantly influence the indentation results.Simulation methods for macro-indentation encompass continuous medium,discontinuous medium,and continuous-discontinuous medium methods,with selection based on their differences in principle.Furthermore,rock macro-indentation can be practically applied to mining engineering,tunneling engineering,and petroleum drilling engineering.Indentation indices serve as valuable tools for characterizing rock strength,brittleness,and drillability.This review sheds light on the development of rock macro-indentation and its extensive application in engineering practice.Specialists in the field can gain a comprehensive understanding of the indentation process and its potential in various rock engineering endeavors. 展开更多
关键词 Rock macro-indentation Indentation test Indentation indices MECHANISM Rock breaking
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Influence of edaphic factors on distribution and condition of Himalayan silver birch(Betula utilis D.Don)communities in the northwestern Indian Himalayas
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作者 Khashti DASILA Renu RAWAL +3 位作者 Tanay BARMAN Sher Singh SAMANT Anita PANDEY Veena PANDE 《Journal of Mountain Science》 SCIE CSCD 2024年第2期590-606,共17页
The basic concept of phytosociology is crucial for the assessment of species composition and dynamic ecological succession of forests supporting ecological services,functions,disturbance,and resilience that lead to th... The basic concept of phytosociology is crucial for the assessment of species composition and dynamic ecological succession of forests supporting ecological services,functions,disturbance,and resilience that lead to the development of integrated areas such as ecological niche modeling and contribute to identifying the valuable bio-indicators which can be used in framing conservation and management planning.B.utilis is one of the most dominant tree species of treeline ecotone in the Himalayan Region.The species is also considered as indicator species for monitoring the past and recent climate change impact.The current study was carried out in the natural populations of B.utilis from the sub-alpine zone of North-western Indian Himalaya.The birch dominated forest harbors a total of 305 plant species comprising Angiosperms(51 families,160 genera and 277 species),Gymnosperms(03 families,05 genera and 07 species)and Pteridophytes(07 families,11 genera and 21 species)with Asteraceae,Ranunculaceae and Rosaceae as dominant family.Birch forests are found dominant in shady moist habitat and North West aspect.Geographical characteristics,anthropogenic and developmental activities affect the population structure of B.utilis and associated species.However,the species has fair regeneration status in the study area.The acidic nature of soil pH and spatial variation in edaphic characteristics may be due to geographical differences,rooting patterns and litter accumulation of below and above-ground vegetation.Biomass estimation of a representative population of B.utilis from each site showed that TAGBD,TCD and TBD were found maximum in ST3(Hamta Pass II site).The CCA analysis determined that environmental variables such as altitude,organic matter,available phosphorous,organic carbon,available nitrogen,and electrical conductivity played a significant role in determining tree species composition and distribution in B.utilis dominated forests. 展开更多
关键词 Species composition Indicator species Biomass North-western Indian Himalaya Regeneration Environmental variables
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Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests
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作者 Anthony GUERRA Fressia N.AMES-MARTÍNEZ Ernesto C.RODRÍGUEZ-RAMÍREZ 《Journal of Mountain Science》 SCIE CSCD 2024年第9期2986-3000,共15页
Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate chan... Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate change.Wood anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme climates.Although the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem tissues.To address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric stress.We performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic factors.Specific wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis species.This study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel traits.Our findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna forests.By evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and adaptability. 展开更多
关键词 Carlquist indices Climatic resilience Vessel traits Fiber Functional trait Hydric stress
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Features of sampling stream sediments of large river valleys under cryolithogenesis conditions in the Balygychan-Sugoy trough,North-East of Russia
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作者 Artem S.Makshakov Raisa G.Kravtsova 《Acta Geochimica》 EI CAS CSCD 2024年第4期638-660,共23页
Comprehensive research has been implemented to raise the efficiency of the geochemical survey of stream sediments(SSs)that formed under the cryolithogenesis conditions.The authors analysed the composition,structure an... Comprehensive research has been implemented to raise the efficiency of the geochemical survey of stream sediments(SSs)that formed under the cryolithogenesis conditions.The authors analysed the composition,structure and specific features of the formation of exogenous anomalous geochemical fields(AGFs)identified through SSs of large river valleys of IV order.In our case,these were the valleys of Maly Ken,Ken and Tap Rivers.These rivers are located in the central and southern parts of the Balygychan-Sugoy trough enclosed in the Magadan region,North-East of Russia.The authors proposed a new technique to sample loose alluvium of SSs in the large river valleys along the profiles.The profiles were located across the valleys.The AGFs of Au,Ag,Pb,Zn,Sn,Bi,Mo and W were studied.Correlations between elements have been established.These elements are the main indicator elements of Au-Ag,Ag-Pb,Sn-Ag,Mo-W and Sn-W mineralization occurring on the sites under study.The results obtained were compared with the results of geochemical surveys of SSs.It is concluded that the AGFs recognized along the profiles reflect the composition and structure of eroded and drained ore zones,uncover completely and precisely the pattern of element distribution in loose sediments of large water flows.The alluvium fraction<0.25 mm seems to be most significant in a practical sense,as it concentrated numerous ore elements.Sampling of this fraction in the river valleys of IV order does not cause any difficulty,for this kind of material is plentiful.The developed technique of alluvium sampling within large river valleys is efficient in searching for diverse mineralization at all stages of prognostic prospecting.It is applicable for geochemical survey of SSs performed at different scales both in the North-East of Russia,as well as other regions with similar climatic conditions,where the SSs are formed under the cryolithogenesis conditions. 展开更多
关键词 Stream sediments Large river valleys Geochemical fields MINERALIZATION Indicator elements Geochemical survey
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Impacts of Aggregation Methods and Trophospecies Number on the Structure and Function of Marine Food Webs
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作者 LI Pengcheng ZHANG Chongliang +4 位作者 XU Binduo JI Yupeng LI Fan REN Yiping XUE Ying 《Journal of Ocean University of China》 CAS CSCD 2024年第1期190-198,共9页
Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also th... Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also the accuracy of models’outputs.Selection of aggregation methods and the number of trophospecies are the keys to study the simplification of food web.In this study,three aggregation methods,including taxonomic aggregation(TA),structural equivalence aggregation(SEA),and self-organizing maps(SOM),were analyzed and compared with the linear inverse model–Markov Chain Monte Carlo(LIM-MCMC)model.Impacts of aggregation methods and trophospecies number on food webs were evaluated based on the robustness and unitless of ecological net-work indices.Results showed that aggregation method of SEA performed better than the other two methods in estimating food web structure and function indices.The effects of aggregation methods were driven by the differences in species aggregation principles,which will alter food web structure and function through the redistribution of energy flow.According to the results of mean absolute percentage error(MAPE)which can be applied to evaluate the accuracy of the model,we found that MAPE in food web indices will increase with the reducing trophospecies number,and MAPE in food web function indices were smaller and more stable than those in food web structure indices.Therefore,trade-off between simplifying food webs and reflecting the status of ecosystem should be con-sidered in food web studies.These findings highlight the importance of aggregation methods and trophospecies number in the analy-sis of food web simplification.This study provided a framework to explore the extent to which food web models are affected by dif-ferent species aggregation,and will provide scientific basis for the construction of food webs. 展开更多
关键词 LIM-MCMC model species aggregation trophospecies number aggregation methods food web indices
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Estimating wheat spike-leaf composite indicator(SLI)dynamics by coupling spectral indices and machine learning
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作者 Haiyu Tao Ruiheng Zhou +6 位作者 Yining Tang Wanyu Li Xia Yao Tao Cheng Yan Zhu Weixing Cao Yongchao Tian 《The Crop Journal》 SCIE CSCD 2024年第3期927-937,共11页
The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering s... The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis.Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years,our objectives were to(i)construct a yield-related phenotypic trait(spike–leaf composite indicator,SLI)accounting for the contribution of the spike to photosynthesis,(ii)develop a novel spectral index(enhanced triangle vegetation index,ETVI3)sensitive to SLI,and(iii)establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms.The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index.ETVI3 maintained a strong correlation with SLI throughout the growth stage,whereas the correlations of other spectral indices with SLI were poor after spike emergence.Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI,with the most accurate estimates of SLI showing coefficient of determination,root mean square error(RMSE),and relative RMSE values of 0.71,0.047,and 26.93%,respectively.These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY.This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection. 展开更多
关键词 Wheat spike photosynthesis Yield-related phenotypic trait Spectral indices Machine learning Estimation
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Cut stumps vs broken stumps:Does it make any difference in the maintenance of plant and lichen biodiversity in Central European mountain forests?
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作者 Monika Staniaszek-Kik Jan Zarnowiec Damian Chmura 《Forest Ecosystems》 SCIE CSCD 2024年第4期457-468,共12页
Fxcessive forest exploitation significantly contributes to land degradation and the creation of human-made deadwood.Stumps are sometimes ignored in studies on the biodiversity of coarse woody debris.We investigated wh... Fxcessive forest exploitation significantly contributes to land degradation and the creation of human-made deadwood.Stumps are sometimes ignored in studies on the biodiversity of coarse woody debris.We investigated whether the type of stump,i.e.broken stumps(naturally created)and cut stumps(formed during forestry operations)had an impact on the species composition and species diversity as well as due to this fact they can be characterized by plant indicators.The research covered 728 spruce stumps(287 broken and 441 cut stumps)that were inhabited by lichens,liverworts,mosses and vascular plants in mountain forest belt(Karkonosze Mts.,Poland).The following types of microhabitats were included in the research:the upper surface and the lateral surface of a stump with both bark and wood.There are statistically significant compositional differences between the two types of stumps,which was demonstrated by ordination analyses and indicator species analysis.According to the generalized linear models,the probability of occurrence increases in cut stumps in case of liverworts and vascular plants and also along the decomposition stages.The generalized linear mixed-effects model showed that there was a higher species richness of liverworts,mosses and vascular plants on the cut stumps and less drier but the reverse situation was in lichens.The generalized additive models for their cover showed similar trends.Almost all of the taxonomic groups were affected by altitude both in terms of species composition and total cover on the stumps.We concluded that cut stumps are an important type of deadwood for biodiversity and provide a convenient habitat,especially for many lichens and bryophytes. 展开更多
关键词 Coarse woody debris Spruce stumps Epixylic flora Plant indicators
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Disinfection Byproducts and Their Precursors in Drinking Water Sources:Origins,Influencing Factors,and Environmental Insights
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作者 Rong Xiao Yang Deng +1 位作者 Zuxin Xu Wenhai Chu 《Engineering》 SCIE EI CAS CSCD 2024年第5期36-50,共15页
Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as ... Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as they tend to be laborious,time-consuming,or technically difficult.Disinfection byproducts(DBPs)are a family of well-known secondary pollutants formed by the reactions of chemical disinfectants with DBP precursors during water disinfection treatment.Since DBP precursors have various origins(e.g.,natural,domestic,industrial,and agricultural sources),and since the formation of DBPs from different precursors in the presence of specific disinfectants is distinctive,we argue that DBPs and DBP precursors can serve as alternative indicators to assess the contamination in water sources and identify pollution origins.After providing a retrospective of the origins of DBPs and DBP precursors,as well as the specific formation patterns of DBPs from different precursors,this article presents an overview of the impacts of various natural and anthropogenic factors on DBPs and DBP precursors in drinking water sources.In practice,the DBPs(i.e.,their concentration and speciation)originally present in source water and the DBP precursors determined using DBP formation potential tests—in which water samples are dosed with a stoichiometric excess of specific disinfectants in order to maximize DBP formation under certain reaction conditions—can be considered as alternative metrics.When jointly used with other water quality parameters(e.g.,dissolved organic carbon,dissolved organic nitrogen,fluorescence,and molecular weight distribution)and specific contaminants of emerging concern(e.g.,certain pharmaceuticals and personal care products),DBPs and DBP precursors in drinking water sources can provide a more comprehensive picture of water pollution for better managing water resources and ensuring human health. 展开更多
关键词 Disinfection byproducts Disinfection byproduct precursors Drinking water sources Contamination indicator Natural factors Human factors
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