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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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Deep learning to estimate ocean subsurface salinity structure in the Indian Ocean using satellite observations
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作者 Jifeng QI Guimin SUN +2 位作者 Bowen XIE Delei LI Baoshu YIN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期377-389,共13页
Accurately estimating the ocean subsurface salinity structure(OSSS)is crucial for understanding ocean dynamics and predicting climate variations.We present a convolutional neural network(CNN)model to estimate the OSSS... Accurately estimating the ocean subsurface salinity structure(OSSS)is crucial for understanding ocean dynamics and predicting climate variations.We present a convolutional neural network(CNN)model to estimate the OSSS in the Indian Ocean using satellite data and Argo observations.We evaluated the performance of the CNN model in terms of its vertical and spatial distribution,as well as seasonal variation of OSSS estimation.Results demonstrate that the CNN model accurately estimates the most significant salinity features in the Indian Ocean using sea surface data with no significant differences from Argo-derived OSSS.However,the estimation accuracy of the CNN model varies with depth,with the most challenging depth being approximately 70 m,corresponding to the halocline layer.Validations of the CNN model’s accuracy in estimating OSSS in the Indian Ocean are also conducted by comparing Argo observations and CNN model estimations along two selected sections and four selected boxes.The results show that the CNN model effectively captures the seasonal variability of salinity,demonstrating its high performance in salinity estimation using sea surface data.Our analysis reveals that sea surface salinity has the strongest correlation with OSSS in shallow layers,while sea surface height anomaly plays a more significant role in deeper layers.These preliminary results provide valuable insights into the feasibility of estimating OSSS using satellite observations and have implications for studying upper ocean dynamics using machine learning techniques. 展开更多
关键词 machine learning convolutional neural network(CNN) ocean subsurface salinity structure(OSSS) indian Ocean satellite observations
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Chronic Hepatitis B in Indian Americans: Lack of Screening and Poor Linkage to Care
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作者 Chul Hyun Soonsik Kim +4 位作者 Emily Li Minhee Lee Mitchell K. Spinnell Joseph McMenamin Dohyun Cho 《International Journal of Clinical Medicine》 CAS 2024年第4期197-209,共13页
Background: Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality in the United States (US) and globally. CHB disproportionately affects Asian Americans and many other immigrant minority ... Background: Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality in the United States (US) and globally. CHB disproportionately affects Asian Americans and many other immigrant minority populations, primarily owing to the high prevalence of CHB in their countries of origin. India is a country with a medium-to-high prevalence of hepatitis B (HB) (>2%) and has over 40 million people infected with hepatitis B virus (HBV), with more than 115,000 deaths annually from HBV-related complications. Indian Americans are one of the largest immigrant populations in the US but remain underdiagnosed and poorly linked to clinical care. We, therefore, assessed the HBV prevalence and evaluated the linkage-to-care (LTC) among Indian Americans to develop strategic plans to reduce the impact of HBV in the US. Methods: Between April 2022 and January 2024, serologic screening and surveys were provided to 328 Indian American adults (age 20 - 80) in New York City. All participants were tested for a triple panel consisting of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core IgG antibody (anti-HBc). A survey was conducted on the subjects chronically infected with HBV regarding their histories of infection. Self-administered questionnaires were employed to evaluate demographic and epidemiologic characteristics. Results: Of 328 screened and evaluated (246 males and 82 females), 10 (3.0%) were HBV-infected, 222 (67.7%) were susceptible to HBV, and 96 (29.3%) were immune. The prevalence of chronic HBV varied between the age groups: 4.6% (age 20 - 40), 3.4% (age 41 - 60), and 1.7% (age 61 - 80). Of 10 chronically infected, only two subjects had been previously diagnosed but were not engaged in care. Conclusion: HBV disproportionately affects Asian Americans, primarily owing to immigration from parts of the world where the disease is endemic. Indian Americans belong to an intermediate-risk group, with an HBV prevalence of >2%, but remain underdiagnosed and poorly linked to care. Our pilot study on Indian American populations, the first of its kind, demonstrates a 3% prevalence of CHB, none of whom are linked to care. In addition, this population has a high percentage of unimmune subjects, creating a large reservoir for future infection. With the growing population of Indian Americans, our findings can be used to develop community-based strategies for HBV screenings and LTC that target high-risk groups. 展开更多
关键词 Hepatitis B Virus Chronic Hepatitis B indian Americans Health Disparity Community-Based Screening Linkage-to-Care
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Indian: Textile industry perspectives from 2023 and hopes for 2024
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《China Textile》 2024年第1期19-21,共3页
The year gone by has been one of the most challenging years for the Indian textile industry.The major challenges have been the fluctuating cotton prices,diminishing demand,capacity under-utilization and dumping of imp... The year gone by has been one of the most challenging years for the Indian textile industry.The major challenges have been the fluctuating cotton prices,diminishing demand,capacity under-utilization and dumping of imported fabrics and garments from China and Bangladesh.The buying by the US and EU has remained quite low and that too for an unusually longer period,which has affected the exports badly. 展开更多
关键词 indian INDUSTRY fluctuating
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Impact of Tropical Indian Ocean Temperature on the Ozone Layer in East Asia
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作者 Mengkun TIAN Yiran GUO +2 位作者 Xiuying WANG Yan CHEN Shichang GUO 《Meteorological and Environmental Research》 2023年第6期1-7,15,共8页
Based on the reanalysis data of monthly mean sea surface temperature (SST) from British Hadley Center and ozone mass mixing ratio from National Aeronautics and Space Administration (NASA) during 1980-2015, two indexes... Based on the reanalysis data of monthly mean sea surface temperature (SST) from British Hadley Center and ozone mass mixing ratio from National Aeronautics and Space Administration (NASA) during 1980-2015, two indexes IOBI and IODI of the main modes characterizing SST changes in the tropical Indian Ocean——Indian Ocean Basin (IOB) and Indian Ocean Dipole (IOD) were calculated firstly, and then the correlation of SST anomaly (SSTA) in the tropical Indian Ocean and ozone mass mixing ratio in the stratosphere over East Asia from 1980 to 2015 was analyzed. Besides, the impact of SST changes in the tropical Indian Ocean on the distribution of ozone layer in East Asia was discussed. The results show that SST changes in the tropical Indian Ocean had significant effects on stratospheric ozone distribution in East Asia, and it was consistent with the temporal changes of IOB and IOD. IOBI and IODI had a certain correlation with stratospheric ozone changes in East Asia, with a particularly significant correlation in the lower stratosphere (70 hPa) and middle stratosphere (40 hPa) especially during spring and autumn. 展开更多
关键词 Tropical indian Ocean East Asia indian Ocean Basin indian Ocean Dipole Stratospheric ozone
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Circulation Patterns Linked to the Positive Sub-Tropical Indian Ocean Dipole 被引量:1
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作者 Chibuike Chiedozie IBEBUCHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期110-128,共19页
The positive phase of the subtropical Indian Ocean dipole(SIOD)is one of the climatic modes in the subtropical southern Indian Ocean that influences the austral summer inter-annual rainfall variability in parts of sou... The positive phase of the subtropical Indian Ocean dipole(SIOD)is one of the climatic modes in the subtropical southern Indian Ocean that influences the austral summer inter-annual rainfall variability in parts of southern Africa.This paper examines austral summer rain-bearing circulation types(CTs)in Africa south of the equator that are related to the positive SIOD and the dynamics through which specific rainfall regions in southern Africa can be influenced by this relationship.Four austral summer rain-bearing CTs were obtained.Among the four CTs,the CT that featured(i)enhanced cyclonic activity in the southwest Indian Ocean;(ii)positive widespread rainfall anomaly in the southwest Indian Ocean;and(iii)low-level convergence of moisture fluxes from the tropical South Atlantic Ocean,tropical Indian Ocean,and the southwest Indian Ocean,over the south-central landmass of Africa,was found to be related to the positive SIOD climatic mode.The relationship also implies that positive SIOD can be expected to increase the amplitude and frequency of occurrence of the aforementioned CT.The linkage between the CT related to the positive SIOD and austral summer homogeneous regions of rainfall anomalies in Africa south of the equator showed that it is the principal CT that is related to the inter-annual rainfall variability of the south-central regions of Africa,where the SIOD is already known to significantly influence its rainfall variability.Hence,through the large-scale patterns of atmospheric circulation associated with the CT,the SIOD can influence the spatial distribution and intensity of rainfall over the preferred landmass through enhanced moisture convergence. 展开更多
关键词 subtropical indian Ocean dipole circulation types RAINFALL South indian Ocean moisture convergence
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The Subsurface and Surface Indian Ocean Dipoles and Their Association with ENSO in CMIP6 models
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作者 Ge SONG Rongcai REN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期975-987,共13页
This study assesses the reproducibility of 31 historical simulations from 1850 to 2014 in the Coupled Model Intercomparison Project phase 6(CMIP6) for the subsurface(Sub-IOD) and surface Indian Ocean Dipole(IOD) and t... This study assesses the reproducibility of 31 historical simulations from 1850 to 2014 in the Coupled Model Intercomparison Project phase 6(CMIP6) for the subsurface(Sub-IOD) and surface Indian Ocean Dipole(IOD) and their association with El Ni?o-Southern Oscillation(ENSO). Most CMIP6 models can reproduce the leading east-west dipole oscillation mode of heat content anomalies in the tropical Indian Ocean(TIO) but largely overestimate the amplitude and the dominant period of the Sub-IOD. Associated with the much steeper west-to-east thermocline tilt of the TIO, the vertical coupling between the Sub-IOD and IOD is overly strong in most CMIP6 models compared to that in the Ocean Reanalysis System 4(ORAS4). Related to this, most models also show a much tighter association of Sub-IOD and IOD events with the canonical ENSO than observations. This explains the more(less) regular Sub-IOD and IOD events in autumn in those models with stronger(weaker) surface-subsurface coupling in TIO. Though all model simulations feature a consistently low bias regarding the percentage of the winter–spring Sub-IOD events co-occurring with a Central Pacific(CP) ENSO, the linkage between a westward-centered CP-ENSO and the Sub-IOD that occurs in winter–spring, independent of the IOD, is well reproduced. 展开更多
关键词 CMIP6 subsurface indian Ocean Dipole surface indian Ocean Dipole El Niño-Southern Oscillation
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Impact of COVID-19 Pandemic on Mental Health of Healthcare Workers–A Perception of Indian Hospital Administrators
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作者 Anahita Ali Santosh Kumar 《International Journal of Mental Health Promotion》 2023年第7期833-845,共13页
Since the coronavirus pandemic,many factors led to the change in the mental well-being of hospital administrators and their staff.The pandemic negatively impacted the availability and capability of health professional... Since the coronavirus pandemic,many factors led to the change in the mental well-being of hospital administrators and their staff.The pandemic negatively impacted the availability and capability of health professionals to deliver essential services and meet rising demand.Therefore,this study aimed to understand the perspective of hospital administrators about issues and challenges that negatively impacted their staff’s mental health and hospital administrators’coping response to mitigate those challenges and issues.An exploratory qualitative study was conducted with 17 hospital administrators(superintendents,deputy superintendents,nursing in charge and hospital in charge)working in a government district hospital of Rajasthan state during September 2022 and October 2022.This study revealed various emerging themes on mental health-related issues,challenges and coping strategies reported by the administrators.Themes and sub-themes that emerged from this study were 1)Perceived mental health of HCWs-perceived importance of mental health,2)Impact of COVID-19 on the mental health of HCWs–common mental health issues,changes in mental health pre and post-pandemic,3)Impact of COVID-19 on health behavior of HCWs-increased self-care and awareness,4)Challenges responsible for poor mental health of HCWs-organizational,ethical and societal challenges and 5)Strategies to retain mental health of HCWs-effective coping strategies.The most common problems were increased levels of stress,feeling fatigued,tiredness,weak and anxiety among the HCWs.Keeping their staff motivated was the biggest challenge reported.Social support,counseling through professionals and demystifying myths were the most effective coping strategies adopted by the participants.In conclusion,this study reported poor mental health-related issues,challenges faced by the HCWs and effective strategies adopted by hospital administrators during tough situations.This study will assist hospital administrators in developing interventions such as regular training programs and workshops to teach effective coping skills to address poor mental health during crises. 展开更多
关键词 Coping strategies indian administrators indian healthcare workers qualitative study COVID-19 mental health
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The Coordinated Influence of Indian Ocean Sea Surface Temperature and Arctic Sea Ice on Anomalous Northeast China Cold Vortex Activities with Different Paths during Late Summer 被引量:1
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作者 Yitong LIN Yihe FANG +3 位作者 Chunyu ZHAO Zhiqiang GONG Siqi YANG Yiqiu YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期62-77,共16页
The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NC... The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NCCV intensity with atmospheric circulations in late summer,the sea surface temperature(SST),and Arctic sea ice concentration(SIC)in the preceding months,are analyzed.The sensitivity tests by the Community Atmosphere Model version 5.3(CAM5.3)are used to verify the statistical results.The results show that the coordination pattern of East Asia-Pacific(EAP)and Lake Baikal high pressure forced by SST anomalies in the North Indian Ocean dipole mode(NIOD)during the preceding April and SIC anomalies in the Nansen Basin during the preceding June results in an intensity anomaly for the first type of NCCV.While the pattern of high pressure over the Urals and Okhotsk Sea and low pressure over Lake Baikal during late summer-which is forced by SST anomalies in the South Indian Ocean dipole mode(SIOD)in the preceding June and SIC anomalies in the Barents Sea in the preceding April-causes the intensity anomaly of the second type.The third type is atypical and is not analyzed in detail.Sensitivity tests,jointly forced by the SST and SIC in the preceding period,can well reproduce the observations.In contrast,the results forced separately by the SST and SIC are poor,indicating that the NCCV during late summer is likely influenced by the coordinated effects of both SST and SIC in the preceding months. 展开更多
关键词 machine learning method Northeast China cold vortex path classification indian Ocean sea surface temperature Arctic sea ice model sensitivity test
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Assessment of Sea Surface Temperature Warming in the Tropical Indian Ocean Simulated by CMIP Models
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作者 ZHANG Xinyou LUO Yulan +1 位作者 LIU Lin SUN Xuguang 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期897-909,共13页
The tropical Indian Ocean is an important region that affects local and remote climate systems,and the simulation of longterm trends in sea surface temperature(SST)is a major focus of climate research.This study prese... The tropical Indian Ocean is an important region that affects local and remote climate systems,and the simulation of longterm trends in sea surface temperature(SST)is a major focus of climate research.This study presents a preliminary assessment of multiple model simulations of tropical Indian Ocean SST warming from 1950 to 1999 based on outputs from the 20 Coupled Model Intercomparison Project(CMIP)Phase 5(CMIP5)models and the 36 CMIP 6(CMIP6)models to analyze and compare the warming patterns in historical simulations.Results indicate large discrepancies in the simulations of tropical Indian Ocean SST warming,especially for the eastern equatorial Indian Ocean.The multimodel ensemble mean and most of the individual models generally perform well in reproducing basin-wide SST warming.However,the strength of the SST warming trends simulated by the CMIP5 and CMIP6 models are weaker than those observed,especially for the CMIP6 models.In addition to the general warming trend analysis,decadal trends are also assessed,and a statistical method is introduced to measure the near-term variability in an SST time series.The simulations indicate large decadal variability over the entire tropical Indian Ocean,differing from observations in which significant decadal trend variability is observed only in the southeastern Indian Ocean.In the CMIP model simulations,maximum decadal variability occurs in boreal autumn,but the observations display the minimum and maximum variability in boreal autumn and spring,respectively. 展开更多
关键词 indian Ocean CMIP5 CMIP6 SST warming trend
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Assessment of Atmospheric Reanalysis Data Based on Buoy Observations over the Tropical Western Indian Ocean in 2019
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作者 LUO Yulan LIU Lin +6 位作者 PAUL Oloo PHILIP Sagero LI Kuiping YANG Yang SU Qinglei LI Qiuchi MIAO Zichen 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期863-873,共11页
Atmospheric reanalysis data are an important data source for studying weather and climate systems.The sea surface wind and sea level pressure observations measured from a real-time buoy system deployed in Kenya’s off... Atmospheric reanalysis data are an important data source for studying weather and climate systems.The sea surface wind and sea level pressure observations measured from a real-time buoy system deployed in Kenya’s offshore area in 2019 conducted jointly by Chinese and Kenyan scientists were used to evaluate the performance of the major high-frequency atmospheric reanalysis products in the western Indian Ocean region.Compared with observations,the sea level pressure field could be accurately simulated using the atmospheric reanalysis data.However,significant discrepancies existed between the surface wind reanalysis data,especially between meridional wind and the observational data.Most of the data provide a complete understanding of sea level pressure,except for the Japanese 55-year Reanalysis data,which hold a significant system bias.The Modern-Era Reanalysis for Research and Applications,Version-2,provides an improved description of all datasets.All the reanalysis datasets for zonal wind underestimate the strength during the study period.Among reanalysis data,NCEP-DOE Atmospheric Model Intercomparison Project reanalysis data presents an inaccurate description due to the worst correlation with the observations.For meridional wind,most reanalysis datasets underestimate the variance,while the European Centre for Medium-Range Weather Forecasts Atmospheric Composition Reanalysis 4 has a larger variance than the observations.In addition to the original data comparison,the diurnal variability of sea level pressure and surface wind are also assessed,and the result indicates that the diurnal variations have a significant gap between observation and reanalysis data.This study indicates that the current high-frequency reanalysis data still have disadvantages when describing the atmospheric parameters in the Western Indian Ocean region. 展开更多
关键词 Bailong buoy REANALYSIS indian Ocean sea level pressure surface wind
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Chemical and physical studies of metallic alloy-based old Indian coins with LIBS coupled with multivariate analysis
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作者 Vikas GUPTA Abhishekh Kumar RAI +3 位作者 Tejmani KUMAR Rajendhar JUNJURI G Manoj KUMAR A K RAI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第9期91-103,共13页
The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various ... The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various alloys.Thirteen old Indian coins in different years of circulation,(1922–1986)were selected for the study.The concentrations were determined by Calibration free LIBS(CF-LIBS)method.The concentration of cuprum(Cu)is negligible,and aluminum(Al)is maximum in the first five coins,and vice-versa in the remaining eight coins.Two different multivariate methods,Principal Component Analysis(PCA)and Soft Independent Modelling of Class Analogy(SIMCA)have been used to classify and identify the coins.PCA classified all thirteen samples into four main alloy categories.The discernment of unknown samples to their probable class membership of alloy was performed using SIMCA.The surface hardness(Brinell hardness number)is linearly correlated with the plasma temperature and LIBS intensity ratios.The sample surface of the first and fifth coin belongs to Al-alloy,having the least surface hardness,and it became harder for Cu–Ni alloy,Ni-brass alloy,and bronze alloy.The hardness of the surface is more for bronze sample twelve.It is also observed that the plasma temperature increases monotonically with the Brinell hardness number.This analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins. 展开更多
关键词 LIBS metallic alloy stoichiometric ablation PCA SIMCA old indian coins surface hardness
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Spatial Distribution and Seasonal Variation of Hypoxic Zone in the Eastern Equatorial Indian Ocean
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作者 XIE Linping WANG Baodong +5 位作者 XIN Ming WANG Ying SUN Xia WEI Qinsheng LIU Lin YUAN Chao 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期918-929,共12页
The spatial distribution and seasonal variations of the hypoxic zone in the eastern equatorial Indian Ocean were investigated using survey data collected from four cruises from 2013 to 2018.Results showed that hypoxic... The spatial distribution and seasonal variations of the hypoxic zone in the eastern equatorial Indian Ocean were investigated using survey data collected from four cruises from 2013 to 2018.Results showed that hypoxic zone occurred all year round in the eastern equatorial Indian Ocean,and it spread southward in the shape of a double tongue at two depths with one at subsurface centered at a depth of 150 m and the other in intermediate water centered at a depth of 800 m.The southward expansion and maximum thickness of the hypoxic zone were greatest in the spring inter-monsoon and least in the summer monsoon.The hypoxic zone originated from the southward expansion of the hypoxic water in the Bay of Bengal and its spatial distribution was driven by southward output flux of mid-deep(100–1000 m)hypoxic water from the Bay of Bengal.The hypoxia southward expansion was blocked near the equator in the subsurface layer,because of mixing with multiple zonal circulations(e.g.,Wyrtki Jets and the equatorial undercurrent),which meant that the hypoxic zone extended over a smaller area than in the intermediate water.These new findings will contribute to an improved understanding of the hypoxic zone and will contribute to circulation research,particularly about intermediate circulation in the eastern equatorial Indian Ocean. 展开更多
关键词 hypoxic zone spatial distribution vertical structure seasonal variation eastern equatorial indian Ocean
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The Origin and Preservation of Suspended Barites near the 90°E Ridge in the Northeastern Indian Ocean
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作者 BU Xuejiao LIU Ming +5 位作者 DING Yi YANG Yadi HUANG Mu SUN Xiaoxia FAN Dejiang YANG Zuosheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期88-98,共11页
Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian Ocean.Four distinct morphological types of marine barites were distinguished:e... Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian Ocean.Four distinct morphological types of marine barites were distinguished:euhedral-subhedral crystals,oval or round crystals,rhombic crystals,and irregular crystals.The barite crystals in the study area are typically fine,with a dominant size of 1–3μm.The vertical distribution of barites is significantly affected by the formation and sedimentation processes.Barites begin to appear at a depth of 30 m and are formed primarily from the surface to the depth of 2000m with a concentration peak at the depth of 200m,where particles are coarser than those in the other layers.The barites begin to settle and dissolve once formed in the water column,resulting in finer barite particles and lower particle concentrations.The formation of barite crystals is related to biological processes associated with the decomposition of barium-rich skeletons in the microenvironment of decaying organic matter that is affected by the primary productivity and dissolved oxygen content in the water column.The dissolving process of barite crystals showed similar variation with the concentration of dissolved barium in ocean water,and the substitution of strontium for barite in crystals promotes the selective dissolution of barite and exerts an important impact on its morphology.It is approximately 33%of barites in the amount and 22%in the concentration to settle to the bottom of the water column compared to that observed in the main barite formation zone. 展开更多
关键词 marine barite indian Ocean origin and sedimentation process dissolution and preservation
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Mixed layer warming by the barrier layer in the southeastern Indian Ocean
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作者 Kaiyue Wang Yisen Zhong Meng Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第12期32-38,共7页
The southeastern Indian Ocean is characterized by the warm barrier layer(BL)underlying the cool mixed layer water in austral winter.This phenomenon lasts almost half a year and thus provides a unique positive effect o... The southeastern Indian Ocean is characterized by the warm barrier layer(BL)underlying the cool mixed layer water in austral winter.This phenomenon lasts almost half a year and thus provides a unique positive effect on the upper mixed layer heat content through the entrainment processes at the base of the mixed layer,which has not been well evaluated due to the lack of proper method and dataset.Among various traditional threshold methods,here it is shown that the 5 m fixed depth difference can produce a reliable and accurate estimate of the entrainment heat flux(EHF)in this BL region.The comparison between the daily and monthly EHF warming indicates that the account for high-frequency EHF variability almost doubles the warming effect in the BL period,which can compensate for or even surpass the surface heat loss.This increased warming is a result of stronger relative rate of the mixed layer deepening and larger temperature differences between the mixed layer and its immediate below in the daily-resolving data.The interannual EHF shows a moderately increasing trend and similar variabilities to the Southern Annular Mode(SAM),likely because the mixed layer deepening under the positive SAM trend is accompanied by enhanced turbulent entrainment and thus increases the BL warming. 展开更多
关键词 barrier layer mixed layer entrainment heat flux high-frequency variability southeastern indian Ocean
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Subthermocline eddies carrying the Indonesian Throughflow water observed in the southeastern tropical Indian Ocean
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作者 Guangbing Yang Quanan Zheng Xuejun Xiong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期1-13,共13页
We observed a subthermocline eddy(STE)with a cold and fresh core during an observation cruise along a transect of 10°S in the southeastern tropical Indian Ocean(SETIO)in December 2017.The vertical scale,speed rad... We observed a subthermocline eddy(STE)with a cold and fresh core during an observation cruise along a transect of 10°S in the southeastern tropical Indian Ocean(SETIO)in December 2017.The vertical scale,speed radius,and maximum swirl velocity of the STE were about 200 m,55 km,and 0.5 m/s,respectively.The mean Rossby number and Burger number of the STE were then estimated to be about−0.7 and 2.4,indicating the STE was a submesoscale coherent vortex.The STE core water had characteristics of the Indonesian Throughflow(ITF)water and was distinct from that of surrounding areas.By examining Argo float data,another STE was well captured by five successive profiles of the same Argo float.Both STEs showed significant temperature and salinity anomalies at theσ0=26.0-26.5 kg/m3 surfaces.With the assumption that the low-salinity ITF water parcels could be carried only by surface eddies and the STEs,the Argo profiles,which detected low-salinity ITF water and were located outside a surface eddy,were believed to be inside an STE and were used to analyze the distribution,origin,and generation mechanism of the STE.The results suggested that the STEs carrying ITF water may be generated under topography-current interaction at the eastern coastal waters or under front-induced subduction in the area away from coastal waters.Those STEs may be widely distributed in the SETIO and may play a role in ITF water parcel transport. 展开更多
关键词 subthermocline eddy southeastern tropical indian Ocean Indonesian Throughflow submesoscale coherent vortex
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Seasonal Distribution of Observed Colored Dissolved Organic Matter(CDOM)in the Eastern Indian Ocean
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作者 CAI Xiaoqing MENG Jie +6 位作者 YUAN Chao LIU Rongjie HOU Erhu BI Dayong LI Yaoru QIAN Chengcheng ZHONG Shan 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期886-896,共11页
Colored dissolved organic matter(CDOM)is a crucial constituent that affects the optical absorption properties of seawater.Owing to the relatively limited measured data on the spatial distribution characteristics of CD... Colored dissolved organic matter(CDOM)is a crucial constituent that affects the optical absorption properties of seawater.Owing to the relatively limited measured data on the spatial distribution characteristics of CDOM in the tropical eastern Indian Ocean,this study analyzes the optical absorption characteristics of CDOM in the southeast Indian Ocean using the data collected during four seasons from 2013 to 2017.This work also systematically describes the seasonal horizontal and vertical distribution characteristics of CDOM in this area and conducts a preliminary analysis of the relevant factors affecting CDOM absorption characteristics in this region.Results indicate that the CDOM ag(440)during summer was remarkably lower than that in the coastal waters of Europe and coastal waters of China but slightly higher than that in the western and southeast Pacific.The spatial distribution of surface CDOM shows remarkable seasonal differences,and the spatial distribution characteristics of CDOM in the 5°S,92°E region differ between spring/summer and autumn/winter.The values of ag(400)and ag(440)are weak/strong at a surface/subsurface level of 100 m,with differences found between summer and winter.The correlation of CDOM with temperature,salinity,and chlorophyll-a concentration is relatively low,indicating that CDOM is an independent driving mechanism influenced by phytoplankton degradation,photobleaching,and water mixing. 展开更多
关键词 colored dissolved organic matter tropical eastern indian Ocean distribution characteristics influencing factors
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Deep Convolutional Neural Networks for South Indian Mango Leaf Disease Detection and Classification
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作者 Shaik Thaseentaj S.Sudhakar Ilango 《Computers, Materials & Continua》 SCIE EI 2023年第12期3593-3618,共26页
The South Indian mango industry is confronting severe threats due to various leaf diseases,which significantly impact the yield and quality of the crop.The management and prevention of these diseases depend mainly on ... The South Indian mango industry is confronting severe threats due to various leaf diseases,which significantly impact the yield and quality of the crop.The management and prevention of these diseases depend mainly on their early identification and accurate classification.The central objective of this research is to propose and examine the application of Deep Convolutional Neural Networks(CNNs)as a potential solution for the precise detection and categorization of diseases impacting the leaves of South Indian mango trees.Our study collected a rich dataset of leaf images representing different disease classes,including Anthracnose,Powdery Mildew,and Leaf Blight.To maintain image quality and consistency,pre-processing techniques were employed.We then used a customized deep CNN architecture to analyze the accuracy of South Indian mango leaf disease detection and classification.This proposed CNN model was trained and evaluated using our collected dataset.The customized deep CNN model demonstrated high performance in experiments,achieving an impressive 93.34%classification accuracy.This result outperformed traditional CNN algorithms,indicating the potential of customized deep CNN as a dependable tool for disease diagnosis.Our proposed model showed superior accuracy and computational efficiency performance compared to other basic CNN models.Our research underscores the practical benefits of customized deep CNNs for automated leaf disease detection and classification in South Indian mango trees.These findings support deep CNN as a valuable tool for real-time interventions and improving crop management practices,thereby mitigating the issues currently facing the South Indian mango industry. 展开更多
关键词 South indian mango tree customized deep CNN mango leaf disease CLASSIFICATION ACCURACY
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Record of hydrothermal activity in the Yuhuang hydrothermal field and its implications for the Southwest Indian Ridge:evidence from sulfide chronology
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作者 Weifang Yang Chunhui Tao +6 位作者 Shili Liao Jin Liang Wei Li Teng Ding Ágata Alveirinho Dias Xuefeng Wang Lisheng Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期59-68,共10页
The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previ... The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges. 展开更多
关键词 Southwest indian Ridge seafloor massive sulfides 230Th/U dating hydrothermal activity mass accumulation
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Indian Solar Panel Initiatives in Reducing Carbon Dioxide Emissions
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作者 Manoj K. Khanna Sarika Malik +1 位作者 Hemant Kumar   Suruchi 《Energy and Power Engineering》 CAS 2023年第4期191-203,共13页
Environmental degradation and the emission of greenhouse gases particularly carbon dioxide have expanded problems to human wellness and to the atmosphere. The second-most populated country in the globe, India, is amon... Environmental degradation and the emission of greenhouse gases particularly carbon dioxide have expanded problems to human wellness and to the atmosphere. The second-most populated country in the globe, India, is among the primary users of conventional resources, which leads to global warming. The growth rate is anticipated to raise more before 2050, which will cause the brisk industrial expansion and rising energy demand to both increases. In order to reduce carbon emissions and meet energy requirements, many countries use alternate usage of renewable energy particularly solar energy. In this review we aim to study solar panel schemes initiated by India, mainly focusing on National Solar Mission. This study also reviews the present solar installed capacity, solar panel scheme 2022, and initiatives and outcomes of solar panels in residences and offices. This study reviewed that by using solar panel resources, the (MNRE) Ministry of New and Renewable Energy hopes to help the Indian Government reach its purpose of 100 GW solar installed capacity by end of 2022. Despite having an amazing 40 GW of solar power installed capacity till December 2021, India is still far from reaching its own goal of 100 GW by March 2023 as per NSM. In essence, this means that India will need to change a few of its ongoing plans further. 展开更多
关键词 Renewable Energy Solar Panel Carbon Dioxide Emission Schemes of the indian Government INITIATIVES
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