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Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin
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作者 Wen-Yang Wang Xiong-Qi Pang +3 位作者 Ya-Ping Wang Zhang-Xin Chen Fu-Jie Jiang Ying Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期115-124,共10页
With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can b... With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum geology.Since it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the DLOA.Hence,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the depth.In this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained collectively.The depth corresponding to a dry layer ratio of 100%is the DLOA.Based on this,a quantitative prediction model for the DLOA was finally built.The results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep layer.The critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the reservoir.The depth of the DLOA was 9,000 m.This study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling. 展开更多
关键词 Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model
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Regulation of different light conditions for efficient biomass production and protein accumulation of Spirulina platensis
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作者 Yufei ZHANG Xianjun LI +9 位作者 Yuhui LI Shiqi LIU Yanrui CHEN Miao JIA Xin WANG Lu ZHANG Qiping GAO Liang ZHANG Daoyong YU Baosheng GE 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期174-186,共13页
Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.I... Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.In this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically characterized.Under different colored lights,S.platensis all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light intensities.At the same light intensity,different colored lights show different growth rate of S.platensis following the sequence of red>white>green>yellow>blue.The maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red LED.The energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>yellow.Transcriptomic analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism pathways.This study provides a conducive and efficient way to promote biomass production and protein accumulation of S.platensis by regulating light conditions. 展开更多
关键词 MICROALGAE light emitting diode protein accumulation biomass production transcriptomic analysis
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Accumulation of Heavy Metals in Maga-Pouss Rice Fields (Far-North Region, Cameroon) and Transfer to Rice Grains
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作者 Diane Madomguia Gilbert Bello Basokdou +3 位作者 Kalieu W. Appoline Isabelle Patrice Kuitekam Dongo Edouard Nya Serge Hubert Zebaze Togouet 《Agricultural Sciences》 2024年第3期311-326,共16页
Monitoring of heavy metals contamination of agricultural products and their transfer and bioaccumulation in crops like rice has become a hot topic worldwide over the last two decades. The present study was carried out... Monitoring of heavy metals contamination of agricultural products and their transfer and bioaccumulation in crops like rice has become a hot topic worldwide over the last two decades. The present study was carried out to determine the accumulation of heavy metals in rice fields and their transfer to rice grains. Soil, irrigation water and rice grains samples were gathered in Maga-Pouss, Far-North, Cameroon. Concentrations of six heavy metals (lead, cadmium, zinc, copper, iron and mercury) were evaluated by Atomic Absorption Spectrophotometer (AAS). Mercury was not detected in this study. Average concentrations of metals were in this order (in mg/kg): Fe (188.60 ± 97.06) > Pb (63.63 ± 7.11) > Cd (2.59 ± 0.29) > Zn (1.10 ± 1.05) > Cu (0.80 ± 0.73) in water and Pb (105.50 ± 31.11) > Fe (105.50 ± 31.11) > Cu (45.93 ± 14.39) > Zn (22.52 ± 6.40) > Cd (3.15 ± 0.49) in soil. Water in Maga-Pouss rice fields appears to be more harmful than the soil, notably for lead, cadmium and copper. In rice grains, heavy metals were found in this order (mg/kg): Fe (188.01 ± 82.62) > Cu (27.20 ± 0.00) > Zn (23.61 ± 12.42) > Pb (19.50 ± 19.91) > Cd (2.02 ± 1.05). The mean bioconcentration factor (BCF) of metals from soil to rice grains was in the following order: Fe (2.60) > Zn (1.05) > Cd (0.64) > Cu (0.59) > Pb (0.18). From water to rice grains, the order is: Cu (37.26) > Zn (22.49) > Cd (6.97) > Pb (2.74) > Fe (1.94). Rice field pH and electrical conductivity favored the uptake of lead, copper and cadmium by rice grains. The findings of this study will be good documentation for risk assessment, and decision-making by environmental managers in this region. 展开更多
关键词 Heavy Metals Rice Field Bioconcenration Factor Maga-Pouss accumulation
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Acceptance and Experience of HIV-Infected Adolescents in Two Hospitals in Yaoundé
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作者 Isabelle Mekone Nkwele Nelly Kamgaing +7 位作者 Pierrette Amanda Emah Manga Jeannette Épée Ngoué Hélène Kamo Sélangai Claude Audrey Meguieze Nsoh Ndeh-Fofang Serge Tchoukoua Jean-Baptiste Fotso Djemo Paul Koki Ndombo 《Open Journal of Pediatrics》 2024年第2期435-443,共9页
Introduction: Access to antiretroviral drugs has improved the survival of children infected with the Human Immunodeficiency Virus (HIV). As they reach adolescence, they are confronted with various constraints related ... Introduction: Access to antiretroviral drugs has improved the survival of children infected with the Human Immunodeficiency Virus (HIV). As they reach adolescence, they are confronted with various constraints related to the infection and its treatment, in addition to those of the growth period they are going through. The main aim of the study was to assess the acceptance and describe the experience of HIV infection by infected adolescents but also to investigate the factors associated with good acceptance and a positive experience. Methodology: The cross-sectional analytic study concerned HIV-infected adolescents aged 15 to 19 followed up at the Chantal Biya Foundation-Mother and Child Centre (CME-FCB) and the Yaoundé University Hospital Centre (CHUY) between February 2020 and June 2020. The study saw participants complete a questionnaire containing socio-demographic data and assessing acceptance and experience with the infection. Data analysis was accomplished using Epi info software version 7.2.2.6. Results: One hundred and thirteen HIV-infected adolescents were included in the study. The sex ratio was 0.68 and the mean age was 17 years. More than half of the adolescents had a good acceptance and positive experience with the infection. Related factors were the adolescent’s perception of good health and participation in an association with other infected adolescents. Conclusion: Emphasizing the psychological and educational follow-up of infected adolescents and encouraging their participation in associations for adolescents living with HIV could reduce the consequences of poor acceptance and ensure a better transition to adulthood. . 展开更多
关键词 HIV ADOLESCENT ACCEPTANCE experience
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Finding biomarkers of experience in animals
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作者 Sarah Babington Alan J.Tilbrook +9 位作者 Shane K.Maloney Jill N.Fernandes Tamsyn M.Crowley Luoyang Ding Archa H.Fox Song Zhang Elise A.Kho Daniel Cozzolino Timothy J.Mahony Dominique Blache 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期925-944,共20页
At a time when there is a growing public interest in animal welfare,it is critical to have objective means to assess the way that an animal experiences a situation.Objectivity is critical to ensure appropriate animal ... At a time when there is a growing public interest in animal welfare,it is critical to have objective means to assess the way that an animal experiences a situation.Objectivity is critical to ensure appropriate animal welfare outcomes.Existing behavioural,physiological,and neurobiological indicators that are used to assess animal welfare can verify the absence of extremely negative outcomes.But welfare is more than an absence of negative outcomes and an appropriate indicator should reflect the full spectrum of experience of an animal,from negative to positive.In this review,we draw from the knowledge of human biomedical science to propose a list of candidate biological markers(biomarkers)that should reflect the experiential state of non-human animals.The proposed biomarkers can be classified on their main function as endocrine,oxidative stress,non-coding molecular,and thermobiological markers.We also discuss practical challenges that must be addressed before any of these biomarkers can become useful to assess the experience of an animal in real-life. 展开更多
关键词 Animal experience Animal welfare BIOMARKER STRESS Welfare assessment
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Psychological experience of breastfeeding among primiparous women with lactating mastitis:A qualitative research
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作者 Ye LI Jingjin XU Ling TANG 《Journal of Integrative Nursing》 2024年第3期155-161,共7页
Objective:The objective of this study is to comprehensively understand the psychological experience of primiparous women during breastfeeding while dealing with lactating mastitis and to establish a reliable foundatio... Objective:The objective of this study is to comprehensively understand the psychological experience of primiparous women during breastfeeding while dealing with lactating mastitis and to establish a reliable foundation for tailored support measures.Methods:Twenty primiparous mothers from a tertiary hospital in Beijing between January and March 2023 were chosen using purposive sampling for semi-structured interviews.After conducting 20 interviews,data saturation was achieved.The Colaizzi’s seven-step analytical approach was employed to analyze,summarize,and refine the identified themes.Results:Among primiparous women afflicted by lactating mastitis,the primary themes regarding breastfeeding attitudes included three key aspects:(1)uncertainty during the initial diagnosis phase,(2)intricate emotional journey during treatment,and(3)positive psychological outlook during the recovery stage.Conclusion:Primiparous women undergoing lactating mastitis experience substantial physical and psychological strain.It is crucial for medical personnel,family caregivers,and society at large to be attuned to the emotions of these patients.Tailored support measures should be offered to enhance patients’physical and mental well-being and facilitate disease recovery. 展开更多
关键词 Lactation mastitis NURSING patient experience psychological experience
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Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation
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作者 Lichao Zhai Lihua Zhang +7 位作者 Yongzeng Cui Lifang Zhai Mengjing Zheng Yanrong Yao Jingting Zhang Wanbin Hou Liyong Wu Xiuling Jia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1179-1194,共16页
Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CA... Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity. 展开更多
关键词 chemical fertilizer dry mater accumulation kernel position effect N uptake organic fertilizer
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Effects of low molecular weight polysaccharide from Sargassum thunbergii against palmitic acid-induced intracellular lipid accumulation in 3T3-L1 adipocyte and HepG2 cells
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作者 Hyo-Geun Lee D.P.Nagahawatta +4 位作者 M.J.M.S.Kurera Kyung-Mo Song Yun-Sang Choi You-Jin Jeon Min-Cheol Kang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2244-2252,共9页
Low molecular weight polysaccharides can be isolated from Sargassum thunbergii(LMPST)and in vitro experiments were conducted to evaluate the inhibitory effects on lipids.Two natures of LMPST were attained from S.thunb... Low molecular weight polysaccharides can be isolated from Sargassum thunbergii(LMPST)and in vitro experiments were conducted to evaluate the inhibitory effects on lipids.Two natures of LMPST were attained from S.thunbergii and appraised their LMPST on palmitic acid(PA)induced lipid accretion in Hep G2,and 3T3-L1 cells.LMPST treatment lessened lipid deposition and intracellular free fatty acid and triglyceride intensities in PA-treated above mentioned cells.The mechanistic study publicized that LMPST2 significantly suppressed adipogenesis and stimulated the PA-treated 3T3-L1 cells occupied in the lipolysis pathway.Furthermore,in PA-treated Hep G2 cells,the free fatty acid oxidation was significantly increased by LMPST2.Given these constructive properties of LMPST2 from S.thunbergii,is a potential candidate for diminishing the intracellular lipids,and for a therapeutic agent in those conditions. 展开更多
关键词 Sargassum thunbergii Low molecular weight polysaccharide Lipid accumulation OBESITY Liver steatosis
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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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Paleoenvironmental reconstruction and organic matter accumulation of the paleogene shahejie oil shale in the Zhanhua Sag, Bohai Bay Basin, Eastern China
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作者 Xiao-Lin Wang Xiao-Min Zhu +5 位作者 Jin Lai Xing-Yue Lin Xiang Wang Yu-Shan Du Chao Huang Yu-Rui Zhu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1552-1568,共17页
The controlling factors of organic-rich shale accumulation is essential for the exploration and development of shale oil and gas resources.The sedimentary environment plays a vital role in the formation of organic-ric... The controlling factors of organic-rich shale accumulation is essential for the exploration and development of shale oil and gas resources.The sedimentary environment plays a vital role in the formation of organic-rich sediments in lacustrine facies.This article unravels the mineralogy,geochemistry,and paleoenvironmental evolution during the deposition of the Paleogene Shahejie Formation(Es_(3)^(L)).It discusses the effects of paleoclimate,paleosalinity,paleoredox conditions,paleowater depth,and paleoproductivity on organic matter(OM)enrichment.Finally,the OM enrichment model was established.The results show that the mineralogical compositions are mainly composed of calcite(avg.40.13%),quartz(avg.21.64%)and clay minerals(avg.24.07%),accompanied by dolomite(avg.7.07%),feldspar(avg.6.36%)and pyrite(avg.2.95%).The Es_(3)^(L) shale has a high abundance of OM,with total organic carbon(TOC)ranging from 1.07%to 5.12%.The organic matter type is mainly composed of type I-II_(1) kerogen,which is generally considered a good-quality source rock.The source of OM is a mixture of lower bacteria,algae,and plants.During the early sedimentary period,the paleoclimate was dry and cold,with high salinity,intense reducibility,and relatively low productivity.During the late sedimentary period,the climate became warmer and more humid.As a result,the salinity decreased to a level that was suitable for biological reproduction,and productivity increased gradually due to the input of terrigenous plants.Paleosalinity and paleoclimate determined the environment of the sedimentary period,in addition,paleoproductivity and paleoredox condition indicated the formation and preservation conditions of OM.The warm and humid climate,brackish water,suitable reduction conditions and high productivity are the favorable conditions for the generation and preservation of organic matter.The research results may have implications for the genetic mechanisms of organic matter accumulation.They will provide theoretical and technical insights into the exploration and development of shale oil. 展开更多
关键词 Elemental geochemical PALEOENVIRONMENT Organic matter accumulation Paleogene shahejie formation Zhanhua Sag Bohai Bay Basin
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Genetic source,migration and accumulation of helium under deep thermal fluid activities:A case study of Ledong diapir area in Yinggehai Basin,South China Sea
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作者 FENG Ziqi HAO Fang +7 位作者 HU Lin HU Gaowei ZHANG Yazhen LI Yangming WANG Wei LI Hao XIAO Junjie TIAN Jinqiang 《Petroleum Exploration and Development》 SCIE 2024年第3期753-766,共14页
Based on the geochemical parameters and analytical data,the heat conservation equation,mass balance law,Rayleigh fractionation model and other methods were used to quantify the in-situ yield and external flux of crust... Based on the geochemical parameters and analytical data,the heat conservation equation,mass balance law,Rayleigh fractionation model and other methods were used to quantify the in-situ yield and external flux of crust-derived helium,and the initial He concentration and thermal driving mechanism of mantle-derived helium,in the Ledong Diapir area,the Yinggehai Basin,in order to understand the genetic source,migration and accumulation mechanisms of helium under deep thermal fluid activities.The average content of mantle-derived He is only 0.0014%,the ^(3)He/^(4)He value is(0.002–2.190)×10^(−6),and the R/Ra value ranges from 0.01 to 1.52,indicating the contribution of mantle-derived He is 0.09%–19.84%,while the proportion of crust-derived helium can reach over 80%.Quantitative analysis indicates that the crust-derived helium is dominated by external input,followed by in-situ production,in the Ledong diapir area.The crust-derived helium exhibits an in-situ 4 He yield rate of(7.66–7.95)×10^(−13)cm^(3)/(a·g),an in-situ 4 He yield of(4.10–4.25)×10^(−4)cm^(3)/g,and an external 4 He influx of(5.84–9.06)×10^(−2)cm^(3)/g.These results may be related to atmospheric recharge into formation fluid and deep rock-water interactions.The ratio of initial mole volume of 3 He to enthalpy(W)is(0.004–0.018)×10^(−11) cm^(3)/J,and the heat contribution from the deep mantle(X_(M))accounts for 7.63%–36.18%,indicating that deep hot fluid activities drive the migration of mantle-derived 3 He.The primary helium migration depends on advection,while the secondary migration is controlled by hydrothermal degassing and gas-liquid separation.From deep to shallow layers,the CO_(2/3) He value rises from 1.34×10^(9)to 486×10^(9),indicating large amount of CO_(2)has escaped.Under the influence of deep thermal fluid,helium migration and accumulation mechanisms include:deep heat driven diffusion,advection release,vertical hydrothermal degassing,shallow lateral migration,accumulation in traps far from faults,partial pressure balance and sealing capability. 展开更多
关键词 deep thermal fluid HELIUM genetic source migration and accumulation mechanism Yinggehai Basin
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Stability analysis of loose accumulation slopes under rainfall:case study of a high‑speed railway in Southwest China
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作者 Xin Wang Qian Su +2 位作者 Zongyu Zhang Feihu Huang Chenfang He 《Railway Engineering Science》 EI 2024年第1期95-106,共12页
The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce... The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce adverse geological disasters under rainfall conditions.To ensure the smooth construction of the high-speed railway and the subsequent safe operation,it is necessary to master the stability evolution process of the loose accumulation slope under rainfall.This article simulates rainfall using the finite element analysis software’s hydromechanical coupling module.The slope stability under various rainfall situations is calculated and analysed based on the strength reduction method.To validate the simulation results,a field monitoring system is established to study the deformation characteristics of the slope under rainfall.The results show that rainfall duration is the key factor affecting slope stability.Given a constant amount of rainfall,the stability of the slope decreases with increasing duration of rainfall.Moreover,when the amount and duration of rainfall are constant,continuous rainfall has a greater impact on slope stability than intermittent rainfall.The setting of the field retaining structures has a significant role in improving slope stability.The field monitoring data show that the slope is in the initial deformation stage and has good stability,which verifies the rationality of the numerical simulation method.The research results can provide some references for understanding the influence of rainfall on the stability of loose accumulation slopes along high-speed railways and establishing a monitoring system. 展开更多
关键词 High-speed railway Loose accumulation slope Slope stability analysis Rainfall effect Strength reduction
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Ordovician reservoirs in Fuxian area:Gas accumulation patterns and their implications for the exploration of lower Paleozoic carbonates in the southern Ordos Basin
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作者 Ning Gu Juntao Zhang +2 位作者 Xiaohui Jin Fei Yang Lu Liu 《Energy Geoscience》 EI 2024年第1期63-71,共9页
In recent years,the Fuxian area in the southeastern Ordos Basin has undergone significant exploration,with industrial gas flow tested in wells drilled into the Ordovician marine carbonates.Despite this,the gas accumul... In recent years,the Fuxian area in the southeastern Ordos Basin has undergone significant exploration,with industrial gas flow tested in wells drilled into the Ordovician marine carbonates.Despite this,the gas accumulation patterns of this area are not fully understood,posing challenges for further exploration.Our analysis of geological conditions indicates that the Ordovician Majiagou Formation in this area hosts two gas plays:one found in weathering crusts and the other found in interior of the formation.We investigated various typical gas reservoirs in the area,focusing on differentiating the geological conditions and factors controlling gas accumulation in the weathering-crust and interior gas reservoirs.The results suggest three primary gas accumulation patterns in the Majiagou Formation in the Fuxian area:(1)upper gas accumulation in weathering crusts,present in the high parts of landforms such as residual paleo-hills or buried paleo-platform(Pattern I);(2)the stereoscopic pattern with gas accumulation in both weathering crusts and strata interior,arising in high parts of landforms such as residual paleo-hills or buried paleo-platforms(Pattern II);(3)lower gas accumulation in strata interior,occurring in the upper reaches and on both sides of paleo-trenches(Pattern III).This study will serve as a geological basis for future exploration deployment in the Fuxian area. 展开更多
关键词 Gas accumulation ORDOVICIAN Weathering crust play Interior play Fuxian area The ordos basin
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Experiences of Mothers on the Utilization of Elimination of Mother to Child Transmission of HIV Services at Mtendere Clinic, Lusaka
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作者 Ireen Kasongo Silavwe Patricia Katowa Mukwato +2 位作者 Sebean Mayimbo Febiano Phiri Laura Lubinda 《Journal of Biosciences and Medicines》 2024年第4期298-318,共21页
Introduction: Acquired immunodeficiency syndrome is one of the leading causes of mortality among women of reproductive age and Mother to Child Transmission of Human immunodeficiency virus is still a challenge affectin... Introduction: Acquired immunodeficiency syndrome is one of the leading causes of mortality among women of reproductive age and Mother to Child Transmission of Human immunodeficiency virus is still a challenge affecting many countries. Globally, an estimation of 180,000 children under 15 years acquire the Human immunodeficiency virus every day, and more than 90% of those infections are due to Mother to Child Transmission. The study sought to explore the experiences of mothers on the Elimination of Mother to Child Transmission-HIV services at Mtendere Clinic, Lusaka. Materials and Methods: Qualitative interpretive phenomenology study design was employed using in-depth interviews to collect data from a sample that was selected using purposive sampling technique. Thirteen participants were recruited, and these were HIV-positive mothers at least between the ages of 15 and 49 years and enrolled in the Elimination of Mother To Child Transmission-HIV program. The in-depth interviews were audiotape recorded and transcribed verbatim. Data was analyzed using thematic method. Findings: Three main themes that emerged are;living with HIV, support system and barriers to utilization of Elimination of Mother To Child Transmission-HIV services. Most of the participants expressed having acquired knowledge from the program, and received counselling and support from spouses, family as well as health personnel at Mtendere health facility which culminated into a positive experience and enhanced their uptake of the Elimination of Mother to Child Transmission-HIV services. However, barriers to service utilization were identified and these included fear of stigma, negative attitudes from health workers, long waiting times, lack of support and lack of transport to the health facility. Conclusion: Interventions such as community awareness campaigns on Elimination of Mother To Child Transmission-HIV, male involvement and implementing mother-to-mother peer support strategies in Elimination of Mother To Child Transmission-HIV service utilization should be prioritized so as to alleviate stigma and enhancing a positive experience for these mothers thus reducing on the Mother to Child HIV Transmission burden and mortality rates. 展开更多
关键词 Elimination of Mother-to-Child Transmission experiences Barriers UTILIZATION HIV/AIDS
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Qualitative exploration of home life experiences and care needs among elderly patients with temporary intestinal stomas
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作者 Si-Meng Wang Jian-Ling Jiang +5 位作者 Rui Li Juan-Juan Wang Chun-Hong Gu Jia Zeng Xiao-Hui Wei Mei Chen 《World Journal of Gastroenterology》 SCIE CAS 2024年第22期2893-2901,共9页
BACKGROUND This study employed a phenomenological research approach within qualitative research to explore the challenges encountered by elderly individuals with temporary colostomies in managing their daily lives and... BACKGROUND This study employed a phenomenological research approach within qualitative research to explore the challenges encountered by elderly individuals with temporary colostomies in managing their daily lives and care needs.Protecting the anus surgery combined with temporary colostomy has emerged as a prevalent treatment modality for low rectal cancer.However,the ileostomy is susceptible to peri-stoma skin complications,as well as fluid,electrolyte,and nutritional imbalances,posing challenges to effective management.The successful selfmanagement of patients is intricately linked to their adjustment to temporary colostomy;nonetheless,there remains a dearth of research examining the factors influencing self-care among temporary colostomy patients and the obstacles they confront.AIM To investigate the lived experiences,perceptions,and care requirements of temporary colostomy patients within their home environment,with the ultimate goal of formulating a standardized management protocol.METHODS Over the period of June to August 2023,a purposive sampling technique was utilized to select 12 patients with temporary intestinal stomas from a tertiary hospital in Shanghai,China.Employing a phenomenological research approach,a semi-structured interview guide was developed,and qualitative interviews were conducted using in-depth interview techniques.The acquired data underwent coding,analysis,organization,and summarization following Colaizzi’s seven-step method.RESULTS The findings of this study revealed that the experiences and needs of patients with temporary intestinal stomas can be delineated into four principal themes:Firstly,Temporary colostomy patients bear various burdens and concerns about the uncertainty of disease progression;secondly,patients exhibit limited self-care capabilities and face information deficits,resulting in heightened reliance on healthcare professionals;thirdly,patients demonstrate the potential for internal motivation through proactive self-adjustment;and finally,patients express a significant need for emotional and social support.CONCLUSION Home-living patients with temporary intestinal stomas confront multifaceted challenges encompassing burdens,inadequate self-care abilities,informational deficits,and emotional needs.Identifying factors influencing patients’self-care at home and proposing strategies to mitigate barriers can serve as a foundational framework for developing and implementing nursing interventions tailored to the needs of patients with temporary intestinal stomas. 展开更多
关键词 ELDERLY Temporary intestinal stomas Life experiences Intestinal ostomy complications Qualitative study
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Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast
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作者 Olga Nabochenko Mykola Sysyn +1 位作者 Norman Krumnow Szabolcs Fischer 《Railway Engineering Science》 EI 2024年第3期361-383,共23页
The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance expenses.However,the mechanism of the irregul... The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance expenses.However,the mechanism of the irregularities initiation and development is unclear.The motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted track.The long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional track.However,wide sleepers had higher twist and cross-section level irregularities.The present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper form.The DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional one.Nevertheless,the cross-level differential settlements are almost the same for both sleepers.The particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper ends.Ballast flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level irregularities.The mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper ends.The further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the sleeper.The DEM simulation results support the assumption of the mechanism and agree with the experimental studies. 展开更多
关键词 Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation
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Hydrocarbon accumulation history in Lower Cretaceous in northern slope of Bongor Basin in Chad,Central Africa
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作者 WANG Li NIE Zhiquan +5 位作者 DU Yebo WANG Lin MENG Fanchao CHEN Yuliu HU Jie DING Ruxin 《Petroleum Exploration and Development》 SCIE 2024年第1期141-151,共11页
Based on the analysis of the fluid inclusion homogenization temperature and apatite fission track on the northern slope zone of the Bongor Basin in Chad,this paper studied the time and stages of hydrocarbon accumulati... Based on the analysis of the fluid inclusion homogenization temperature and apatite fission track on the northern slope zone of the Bongor Basin in Chad,this paper studied the time and stages of hydrocarbon accumulation in the study area.The results show that:(1)The brine inclusions of the samples from the Kubla and Prosopis formations in the Lower Cretaceous coexisting with the hydrocarbon generally present two sets of peak ranges of homogenization temperature,with the peak ranges of low temperature and high temperature being 75–105℃ and 115–135℃,respectively;(2)The samples from the Kubla and Prosopis formations have experienced five tectonic evolution stages,i.e.,rapid subsidence in the Early Cretaceous,tectonic inversion in the Late Cretaceous,small subsidence in the Paleogene,uplift at the turn of the Paleogene and Neogene,and subsidence since the Miocene,in which the denudation thickness of the Late Cretaceous and after the turn of the Paleogene and Neogene are~1.8 km and~0.5 km,respectively.The cumulative denudation thickness of the two periods is about 2.3 km;(3)Using the brine inclusion homogenization temperature coexisting with the hydrocarbon as the capture temperature of the hydrocarbon,and combining with the apatite fission track thermal history modeling,the result shows that the Kubla and Prosopis formations in the Lower Cretaceous on the northern slope of the Bongor Basin have the same hydrocarbon accumulation time and stages,both of which have undergone two stages of hydrocarbon charging at 80–95 Ma and 65–80 Ma.The first stage of charging corresponds to the initial migration of hydrocarbon at the end of the Early Cretaceous rapid sedimentation,while the second stage of charging is in the stage of intense tectonic inversion in the Late Cretaceous. 展开更多
关键词 Central Africa CHAD Bongor Basin Lower Cretaceous hydrocarbon accumulation stages fluid inclusions apatite fission track
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Hydrocarbon accumulation and orderly distribution of whole petroleum system in marine carbonate rocks of Sichuan Basin,SW China
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作者 GUO Xusheng HUANG Renchun +3 位作者 ZHANG Dianwei LI Shuangjian SHEN Baojian LIU Tianjia 《Petroleum Exploration and Development》 SCIE 2024年第4期852-869,共18页
Based on the situation and progress of marine oil/gas exploration in the Sichuan Basin,SW China,the whole petroleum system is divided for marine carbonate rocks of the basin according to the combinations of hydrocarbo... Based on the situation and progress of marine oil/gas exploration in the Sichuan Basin,SW China,the whole petroleum system is divided for marine carbonate rocks of the basin according to the combinations of hydrocarbon accumulation elements,especially the source rock.The hydrocarbon accumulation characteristics of each whole petroleum system are analyzed,the patterns of integrated conventional and unconventional hydrocarbon accumulation are summarized,and the favorable exploration targets are proposed.Under the control of multiple extensional-convergent tectonic cycles,the marine carbonate rocks of the Sichuan Basin contain three sets of regional source rocks and three sets of regional cap rocks,and can be divided into the Cambrian,Silurian and Permian whole petroleum systems.These whole petroleum systems present mainly independent hydrocarbon accumulation,containing natural gas of affinity individually.Locally,large fault zones run through multiple whole petroleum systems,forming a fault-controlled complex whole petroleum system.The hydrocarbon accumulation sequence of continental shelf facies shale gas accumulation,marginal platform facies-controlled gas reservoirs,and intra-platform fault-and facies-controlled gas reservoirs is common in the whole petroleum system,with a stereoscopic accumulation and orderly distribution pattern.High-quality source rock is fundamental to the formation of large gas fields,and natural gas in a whole petroleum system is generally enriched near and within the source rocks.The development and maintenance of large-scale reservoirs are essential for natural gas enrichment,multiple sources,oil and gas transformation,and dynamic adjustment are the characteristics of marine petroleum accumulation,and good preservation conditions are critical to natural gas accumulation.Large-scale marginal-platform reef-bank facies zones,deep shale gas,and large-scale lithological complexes related to source-connected faults are future marine hydrocarbon exploration targets in the Sichuan Basin. 展开更多
关键词 Sichuan Basin margin oil/gas whole petroleum system carbonate hydrocarbon accumulation hydrocarbon distribution law hydrocarbon exploration target
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Psychological Experience of Mothers of Children with Sickle Cell Disease Followed at the Pediatric Department of Bouaké University Teaching Hospital
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作者 Akanji Iburaima Alamun Aka-Tanoh Koko Aude Hélène +5 位作者 Yao Kouassi Christian Adou Leioh Romeo Sahi Gnantin Josette Landryse Amani Ehi Alexise Eleonore Boune Aboulaye Asse Kouadio Vincent 《Open Journal of Pediatrics》 2024年第1期149-163,共15页
Introduction: Sickle cell disease has physical and emotional repercussions on the child and his family. The aim of this study was to describe the psychosocial experiences of mothers of children with sickle cell diseas... Introduction: Sickle cell disease has physical and emotional repercussions on the child and his family. The aim of this study was to describe the psychosocial experiences of mothers of children with sickle cell disease in order to improve the overall care of the child. Methods: This was a descriptive cross-sectional study carried out in the pediatrics department of Bouaké University Teaching Hospital from June to September 2023. It focused on mothers of major sickle-cell-affected children followed up in the pediatrics department of the Bouaké University Teaching Hospital. The variables studied were sociodemographic, psychological, social and economic. Results: Of the 40 mothers surveyed, 15% were not in school and 32.5% were unemployed. For them, sickle cell disease was of natural (genetic) origin in 90% and supernatural in 10%. They stated that the child had an average age of 36 months (extremes 7 and 108 months) when the disease was discovered. And 52% of them were satisfied with the way the disease was clearly and completely announced. Following the announcement, the questioned mothers said they had felt shock (35%), sadness (31.7%), guilt (23.3%) and discouragement (10%). Anxiety and depression were experienced by 77.5% and 22.5% respectively. In 60% of cases, they stated that the disease was incurable, and the outcome was fatal in 2.5% of cases. The child’s illness was a source of problems in the home in 25% of cases, represented by arguments in 92% and divorce in 8%. In 97.5% of cases, the mother told her family and friends about the child’s illness. In 90% of cases, the mother and child benefited from psychological support from family and friends. Conclusion: Sickle cell disease is a serious illness with a psychological and social impact on mothers. We recommend psychological support for mothers from the moment of diagnosis and throughout follow-up. 展开更多
关键词 Psychosocial experience Sickle Cell Disease Côte d’Ivoire
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Effects of Slow-release Nitrogen on Dry Matter Accumulation,Translocation and Yield of Summer Maize
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作者 Yongfeng XING Guoli CHEN +6 位作者 Changmin WEI Weimeng XU Wanyou SONG Guizhi LI Yanwei WAN Enzhong ZHOU Weifang LI 《Agricultural Biotechnology》 2024年第3期11-13,共3页
[Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six differen... [Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six different treatment were set up:blank control(CK1),slow-release urea 75 kg/hm^(2)(C1),slow-release urea 150 kg/hm^(2)(C2),slow-release urea 225 kg/hm^(2)(C3),slow-release urea 300 kg/hm^(2)(C4)and ordinary urea 300 kg/hm^(2)(CK2),to study the change law of dry matter accumulation and translocation in summer maize.[Results]Treatment slow-release urea 225 kg/hm^(2)(C4)showed summer maize yield,dry matter translocation between organs,grain contribution rate and proportion of grain dry matter in the full ripe stage higher than other treatments.Considering the weight loss and cost factors,slow-release urea 225 kg/hm^(2)(C3)could be recommended as the fertilizing amount for summer maize.[Conclusions]This study provides theoretical reference for rational selection of fertilizers for reducing fertilizer application and increasing fertilizer efficiency,and for production of summer maize in Shajiang black soil region. 展开更多
关键词 Slow-release nitrogen fertilizer Summer maize Dry matter accumulation TRANSLOCATION
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