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反向Northern Blotting对小梅山猪下丘脑发育差异表达ESTs的鉴定 被引量:1
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作者 周春宝 潘孝青 +1 位作者 李霖 丁家桐 《江苏农业科学》 CSCD 北大核心 2009年第3期22-24,共3页
用mRNA差异显示技术从小梅山猪下丘脑不同发育阶段,分离并筛选出3个差异表达ESTs,分别命名为MS01、MS02、MS03。利用地高辛DNA标记与检测技术反向Northern斑点杂交,对分离出来的ESTs进行鉴定结果理想。此法避免了同位素放射性污染,操作... 用mRNA差异显示技术从小梅山猪下丘脑不同发育阶段,分离并筛选出3个差异表达ESTs,分别命名为MS01、MS02、MS03。利用地高辛DNA标记与检测技术反向Northern斑点杂交,对分离出来的ESTs进行鉴定结果理想。此法避免了同位素放射性污染,操作简单,可防止DDRT-PCR过程中假阳性的出现,提高了试验准确性,是一种鉴定差异显示ESTs简单而有效的方法。 展开更多
关键词 小梅山猪 反向northern blotting 下丘脑 ESTS 鉴定
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低温诱导甜菜(Beta vulgaris L.)Ty7Br600基因的Northern blotting和Southern blotting分析 被引量:1
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作者 戴建军 程大友 +3 位作者 常缨 李彩凤 闫桂萍 马凤鸣 《东北农业大学学报》 CAS CSCD 北大核心 2012年第4期80-83,共4页
以低温诱导甜菜幼苗为试验材料,以未进行低温诱导的甜菜幼苗为对照,采用α-32P-ATP放射标记按随机引物标记法标记本实验室克隆的Ty7Br600基因,进行Northern杂交。Northern杂交试验结果显示,在低温诱导培养的甜菜幼苗的RNA群体中,出现较... 以低温诱导甜菜幼苗为试验材料,以未进行低温诱导的甜菜幼苗为对照,采用α-32P-ATP放射标记按随机引物标记法标记本实验室克隆的Ty7Br600基因,进行Northern杂交。Northern杂交试验结果显示,在低温诱导培养的甜菜幼苗的RNA群体中,出现较强的杂交条带,而在未诱导培养的甜菜幼苗的RNA群体中,则几乎没有阳性杂交条带出现。因此,Ty7Br600这一序列有可能是二年生甜菜幼苗经低温诱导处理之后被诱导表达的与抽薹相关的新基因序列。Southern杂交结果发现,在每一组酶切中至少有2~3条条带,表明Ty7Br600确为甜菜基因组片段,也同时表明该基因在甜菜基因组中以2个拷贝或低拷贝形式存在。 展开更多
关键词 甜菜(Beta VULGARIS L.) 低温诱导 northern杂交 SOUTHERN杂交
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A Comparison Between Northern Blotting and Quantitative Real-Time PCR as a Means of Detecting the Nutritional Regulation of Genes Expressed in Roots of Arabidopsis thaliana 被引量:4
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作者 GAN Yin-bo ZHOU Zhong-jing +2 位作者 AN Li-jun BAO Sheng-jie Brian G Forde 《Agricultural Sciences in China》 CAS CSCD 2011年第3期335-342,共8页
Quantitative real-time PCR (qRT-PCR) has become a routine and robust technique for measuring the expression of genes of interest, validating microarray experiments and monitoring biomarkers. However, concerns have b... Quantitative real-time PCR (qRT-PCR) has become a routine and robust technique for measuring the expression of genes of interest, validating microarray experiments and monitoring biomarkers. However, concerns have been raised over the accuracy of qRT-PCR in China as well as in the rest of the world. We have previously used qRT-PCR to study the response of ANR1 and other root-expressed MADS-box genes to fluctuations in the supply of nitrate, phosphate and sulphate under hydroponic growth conditions. In this study, we have used both Northern blotting and qRT-PCR analyses to confirm the nutritional regulation of MADS-box genes in Arabidopsis thaliana and test whether both technologies produce the same results. The information obtained indicated that the qRT-PCR results are consistent with those obtained by Northern blotting hybridization for all the tested root-expressed MADS-box genes, in response to different nitrate, phosphate and sulphate growth conditions. Furthermore, our novel results showed that the expressions of AGL12, AGL18, and AGL19 were all down regulated in response to S and P re-supply in both qRT-PCR and Northern blotting analyses. 展开更多
关键词 Arabidopsis thaliana MADS-BOX nutrient regulation northern blotting quantitative real-time PCR
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反向 Northern Blotting 对绵羊卵巢组织差异表达ESTs的鉴定
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作者 朱靖 杨娜娜 +1 位作者 柳淑芳 杜立新 《生物技术通报》 CAS CSCD 2005年第2期44-46,共3页
利用地高辛DNA标记与检测技术反向Northern斑点杂交,对小尾寒羊和滩羊卵巢组织差异显示ESTs进行鉴定,避免同位素放射性污染,安全性很高且操作简单,提高了实验的准确性,一种鉴定差异显示ESTs简单而有效的方法。在研究基因表达、比较不同... 利用地高辛DNA标记与检测技术反向Northern斑点杂交,对小尾寒羊和滩羊卵巢组织差异显示ESTs进行鉴定,避免同位素放射性污染,安全性很高且操作简单,提高了实验的准确性,一种鉴定差异显示ESTs简单而有效的方法。在研究基因表达、比较不同环境条件下动物组织的mRNA差异表达等方面具有广阔的应用前景。 展开更多
关键词 northern ESTS 差异表达 鉴定 反向 卵巢 绵羊 差异显示 DNA标记 放射性污染 斑点杂交 检测技术 小尾寒羊 基因表达 mRNA 动物组织 环境条件 地高辛 同位素 安全性 准确性
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Coral records of Mid-Holocene sea-level highstands and climate responses in the northern South China Sea 被引量:1
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作者 Yuanfu Yue Lichao Tang +1 位作者 Kefu Yu Rongyong Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期43-57,共15页
High-resolution sea-level data and high-precision dating of corals in the northern South China Sea(SCS)during the Holocene provide a reference and historical background for current and future sea-level changes and a b... High-resolution sea-level data and high-precision dating of corals in the northern South China Sea(SCS)during the Holocene provide a reference and historical background for current and future sea-level changes and a basis for scientific assessment of the evolutionary trend of coral reefs in the SCS.Although sporadic studies have been performed around Hainan Island in the northern SCS,the reconstructed sea level presents different values or is controversial because the indicative meaning of the sea-level indicators were neither quantified nor uniform criteria.Here,we determined the quantitative relationship between modern living coral and sea level by measuring the top surfaces of 27 live Porites corals from the inner reef flat along the east coast of Hainan Island and assessed the accuracy of results obtained using coral as sea-level indicators.Additionally,three in situ fossil Porites corals were analyzed based on elevation measurements,digital X-ray radiography,and U-Th dating.The survey results showed that the indicative meanings for the modern live Porites corals is(146.09±8.35)cm below the mean tide level(MTL).It suggested that their upward growth limit is constrained by the sea level,and the lowest low water is the highest level of survival for the modern live Porites corals.Based on the newly defined indicative meanings,6 new sea-level index points(SLIPs)were obtained and 19 published SLIPs were recalculated.Those SLIPs indicated a relative sea level fluctuation between(227.7±9.8)cm to(154.88±9.8)cm MTL between(5393±25)cal a BP and(3390±12)cal a BP,providing evidences of the Mid-Holocene sea-level highstand in the northern SCS.Besides that,our analysis demonstrated that different sea-level histories may be produced based on different indicative meanings or criteria.The dataset of 276 coral U-Th ages indicates that coral reef development in the northern SCS comprised the initial development,boom growth,decline,and flourishing development again.A comparison with regional records indicated that synergistic effects of climatic and environmental factors were involved in the development of coral reefs in the northern SCS.Thus,the cessation of coral reef development during the Holocene in the northern SCS was probably associated with the dry and cold climate in South China,as reflected in the synchronous weakening of the ENSO and East Asian summer monsoon induced by the reduction of the 65°N summer insolation,which forced the migration of the Intertropical Convergence Zone. 展开更多
关键词 northern South China Sea Middle Holocene sea-level highstand Porites corals climate response
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Zooplankton community response to eddy during dinoflagellate Noctiluca scintillans blooms off Pakistan,northern Arabian Sea
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作者 Mahugnon Boris DEDO Xiping LIAN +2 位作者 Kaizhi LI Chenhui XIANG Yehui TAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1557-1570,共14页
Eddies are major elements of ocean dynamics that affect ocean production.Understanding their effects on plankton distribution may help understand the dynamics of harmful phytoplankton blooms.Previous studies on the ef... Eddies are major elements of ocean dynamics that affect ocean production.Understanding their effects on plankton distribution may help understand the dynamics of harmful phytoplankton blooms.Previous studies on the effects of eddies in the northern Arabian Sea have primarily focused on the zooplankton community,and few have observed zooplankton dynamics during winter blooms of Noctiluca scintillans.We investigated zooplankton community structure and the related environmental variability during a N.scintillans bloom that was affected by an eddy in February 2018.The sampling stations were deployed at eddy core and eddy edge distinguished in salinity,temperature,and velocity.Results show that N.scintillans bloomed at the eddy core with high-velocity currents induced by warm eddies that moved from eddy core to eddy edge.As a result,blooms significantly changed the zooplankton community structure.Non-bloom stations had higher zooplankton diversity than bloom stations.Zooplankton at non-bloom stations were dominated by either tunicates or copepods,such as Thalia democratica and Pleuromamma gracilis.In addition to the influence of N.scintillans blooms,the velocity of eddy currents was a crucial factor on the similarities in the zooplankton community composition between eddy edge and eddy core.Moreover,the lower abiotic factors in bloom area contribute to the structuring of the zooplankton community during N.scintillans blooms. 展开更多
关键词 EDDY zooplankton community Noctiluca scintillans northern Arabian Sea
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Assessment of desertification sensitivity using an improved MEDALUS model in Northern China
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作者 NingJing Tan CaiXia Zhang +1 位作者 YingYing Wu ZhenTing Wang 《Research in Cold and Arid Regions》 CSCD 2024年第3期141-148,共8页
Assessment of land sensitivity to desertification is an important step to support desertification monitoring and control.Based on the Mediterranean Desertification and Land Use(MEDALUS)model,we defined four quality in... Assessment of land sensitivity to desertification is an important step to support desertification monitoring and control.Based on the Mediterranean Desertification and Land Use(MEDALUS)model,we defined four quality indicators(soil,climate,vegetation and management)to evaluate the sensitivity of land in northern China to desertification.We improved MEDALUS via excluding cities from the areas at risk of desertification by means of defining a threshold value for population density.The framework,validated in northern China,further optimizes the model to link priority areas and land restoration programmed to support desertification control.We found that the four indicators influenced and restricted each other,which jointly affected the distribution of desertification sensitivity in northern China.The spatial distribution of sensitivity in northern China showed large regional differences,with clear boundaries and concentrated distributions of regions with high and low sensitivity;the overall sensitivity decreased,with some areas rated as having moderate,severe,and extremely severe sensitivity changing to slight sensitivity;and the influence weight was much higher for the management quality index than for the climate,vegetation,and soil indexes.This suggests that management was the main factor that affected desertification sensitivity in northern China,and that climate factors exacerbated sensitivity,but the factors that are driving the spatial heterogeneity of the influencing factors need further study。 展开更多
关键词 DESERTIFICATION Sensitivity MEDALUS Factor analysis northern China
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Evaluation of Medical Prescribers’ Theoretical Knowledge on Medical Imaging in the Northern Region of Burkina Faso
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作者 Some Milckisédek Judicaël Marouruana Ouedraogo Pakisba Ali +5 位作者 Tankoano Aïda Ida Savadogo Habibou Kindo Bassirou Ouedraogo Nina-Astrid Bamouni Yomboé Abel Diallo Ousseini 《Open Journal of Radiology》 2024年第2期33-41,共9页
Introduction: Medical imaging is a medical specialty that involves producing images of the human body and interpreting them for diagnostic, therapeutic purposes, and for monitoring the progress of pathologies. We aime... Introduction: Medical imaging is a medical specialty that involves producing images of the human body and interpreting them for diagnostic, therapeutic purposes, and for monitoring the progress of pathologies. We aimed to assess the theoretical knowledge of doctors and interns in medical imaging in the northern region of Burkina Faso. Methodology: This was a descriptive cross-sectional survey based on a self-administered questionnaire. Prescribers knowledge was estimated based on scores derived from questionnaire responses. Results: We collected 106 questionnaires out of 163, i.e. a participation rate of 65.03%. The average knowledge score was 81.71% for the contribution of medical imaging to patient management. It was 60.02% for the indications/counter-indications of radiological examinations and 72.56% for the risks associated with exposure to radiation during these examinations. The score was 59.83% for the methods used to select the appropriate radiological examination. As regards the completeness of the clinical and biological information on the forms requesting imaging examinations, the score was 96.65%. Specialist doctors had the highest overall level of knowledge (74.68%). Conclusion: Improved technical facilities, good initial and in-service training, and interdisciplinary collaboration will help to ensure that imaging tests are properly prescribed, leading to better patient care. 展开更多
关键词 Theoretical Knowledge Medical Imaging northern Region Burkina Faso
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Satellite observations of coastal upwelling in the northern Arafura Sea
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作者 Zheyuan YU Zhanjiu HAO +4 位作者 Zhenhua XU Peiwen ZHANG Jia YOU Baoshu YIN Hongwei YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期361-376,共16页
Coastal upwelling is significant for marine ecosystems by lifting nutrient-rich deep waters into the euphotic zone,thereby increasing primary and secondary productivity.The satellite observations show that the norther... Coastal upwelling is significant for marine ecosystems by lifting nutrient-rich deep waters into the euphotic zone,thereby increasing primary and secondary productivity.The satellite observations show that the northern Arafura Sea(NAS),especially in the coastal region,features high chlorophyll-a(chl-a)concentrations,implying a strong coastal upwelling.However,coastal upwelling in the NAS has not received much attention.Based on a semi-automatic image processing technology,the seasonal and interannual variability of coastal upwelling in the NAS are investigated in this study using satellite-observed sea surface temperature(SST)and wind data.The results suggest that there are seasonal coastal upwelling events in the NAS modulated by upwelling-favorable southeast monsoon(SEM).The annual mean days,mean area,and annual mean intensity of coastal upwelling events during the SEM season are 92 days,6514 km^(2),and-5.31×10^(5),respectively,while the corresponding values during the northwest monsoon(NWM)season are 32 days,5569 km^(2),and-1.41×10^(5).It is also found that the SEM coastal upwelling in the NAS displays prominent interannual variability.The strong upwelling events are found in 2010,2013,2016,and 2017 when the southeast monsoon winds were weaker.Further analysis suggests that at the interannual scale,the upwelling index(UI)averaged in the SEM season is negatively correlated with that of three upwelling indicators.This can be attributed to the limitation of onshore geostrophic flow which is evidenced by the negative correlation between the UI and the alongshore difference in sea surface height.This study highlights the important role of the southeast monsoon in the temporal variability of coastal upwelling in the NAS. 展开更多
关键词 coastal upwelling the northern Arafura Sea southeast monsoon interannual variability
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Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China
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作者 HU Bo WEN Qingke +3 位作者 XI Fengjiang LI Mengyao WANG Libing REN Yuejuan 《Chinese Geographical Science》 SCIE CSCD 2024年第1期67-78,共12页
Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local ... Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local governments.However,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration policies.Therefore,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to 2021.The results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland growth.Using the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to 2021.Compared to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 t.The livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in 2015.During the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown steadily.Per capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in 2021.Relying on grassland resources to develop the pastoral ecology also broadens the potential economic development space.Overall,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s development from both an ecological and economic perspective.With the support of scientific evidence,enclosure policy can be extended to more than 110 000 km~2 of grasslands in northern China with similar precipitation and temperature conditions,enhancing the productive and ecological potential of grasslands.The above research results will contribute to the scientific formulation of grassland pasture quality improvement plans in northern China. 展开更多
关键词 ENCLOSURE GRASSLAND ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China
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Human impact gradients via anthropogenic pollen indicators:insights gleaned from a case study in the Rif Mountains(Northern Morocco)
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作者 Aboubakr BOUTAHAR Paloma Cariñanos GONZALEZ +1 位作者 Zouhaire LAMRANI Abderrahmane MERZOUKI 《Journal of Mountain Science》 SCIE CSCD 2024年第12期4223-4235,共13页
Understanding the relationship between modern pollen and vegetation is crucial for interpreting fossil pollen records and assessing human impact on the environment,both of which are essential for effective environment... Understanding the relationship between modern pollen and vegetation is crucial for interpreting fossil pollen records and assessing human impact on the environment,both of which are essential for effective environmental management strategies.Despite numerous studies on fossil pollen records in the Rif landscape,research specifically focusing on modern pollen and its implications for understanding human impact on the natural landscape is notably lacking.This paper presents novel anthropogenic pollen indicators for the Rif Mountains and seeks to evaluate the gradients of human impact on the southern Mediterranean landscape.We employed a combination of modern pollen analysis,vegetation survey,and ordination techniques,incorporating various environmental and land-use variables.Canonical correspondence analysis(CCA)allowed us to evaluate the relationships between pollen types and environmental variables,helping us identify key anthropogenic pollen indicators associated with land use and human activities:Poaceae,Cannabist,Olea-t,and Asteraceae for cultivation;Brassicaceae,Genista-t,Poaceae,Asteraceae and Plantago-t,for grazing;Apiaceae,Urtica-t and Genista-t for slashing and burning.Additionally,an anthropogenic index score(AIS)was calculated for each sampled location.Correspondence analysis(CA)was then used to correlate each specific pollen type with levels of human impact as follows(a)low(e.g.,Cedrus atlantica-t,Quercus canariensis-t),(b)moderate(e.g.,Erica-t,Arbutus unedo-t,Eucalyptus-t),and(c)high(e.g.,Cannabis-t,Brassicaceae,Olea-t,Nicotiana-t).This paper enhances our comprehension of land-use dynamics and impact levels,providing essential insights for evaluating anthropogenic impact trends and human-induced changes in the Rif Mountains landscape. 展开更多
关键词 Modern Pollen analysis Rif mountains Pollen indicators Human impact northern Morocco Anthropogenic index score
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Spatiotemporal patterns and drivers of cultivated land conversion in Inner Mongolia Autonomous Region,northern China
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作者 Xijiri ZHOU Ruiping +1 位作者 BAO Baorong Burenjirigala 《Journal of Arid Land》 SCIE CSCD 2024年第9期1197-1213,共17页
Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and ... Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and urbanization of society.However,the assessment of cultivated land conversion in this area is insufficient,posing a potential risk to cultivated land resources.This study evaluated the evolution and spatiotemporal patterns of cultivated land conversion in Inner Mongolia Autonomous Region,China,and the driving factors to improve rational utilization and to protect cultivated land resources.The spatiotemporal patterns of cultivated land conversion in Inner Mongolia were analyzed using the cultivated land conversion index,kernel density analysis,a standard deviation ellipse model,and a geographic detector.Results showed that from 2000 to 2020,the trends in cultivated land conversion area and rate in Inner Mongolia exhibited fluctuating growth,with the total area of cultivated land conversion reaching 7307.59 km^(2) at a rate of 6.69%.Spatial distribution of cultivated land conversion was primarily concentrated in the Hetao Plain,Nengjiang Plain,Liaohe Plain,and the Hohhot-Baotou-Ordos urban agglomeration.Moreover,the standard deviational ellipse of cultivated land conversion in Inner Mongolia exhibited a directional southwest-northeast-southwest-northeast distribution,with the northeast-southwest direction identified as the main driving force of spatial change in cultivated land conversion.Meanwhile,cultivated land conversion exhibited an increase-decrease-increase change process,indicating that spatial distribution of cultivated land conversion in Inner Mongolia became gradually apparent within the study period.The geographic detector results further revealed that the main driving factors of cultivated land conversion in Inner Mongolia were the share of secondary and tertiary industries and per-unit area yield of grain,with explanatory rates of 57.00%,55.00%,and 51.00%,respectively.Additionally,improved agricultural production efficiency and the coordinated development of population urbanization and industry resulted in cultivated land conversion.Collectively,the findings of this study indicated that,from 2000 to 2020,the cultivated land conversion in Inner Mongolia was significant and fluctuated in time,and had strong spatial heterogeneity.The primary drivers of these events included the effects of agriculture,population,and social economy. 展开更多
关键词 cultivated land conversion spatiotemporal variation standard deviation elliptical models geographic detector northern China
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A Multi-Strategy-Improved Northern Goshawk Optimization Algorithm for Global Optimization and Engineering Design
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作者 Liang Zeng Mai Hu +2 位作者 Chenning Zhang Quan Yuan Shanshan Wang 《Computers, Materials & Continua》 SCIE EI 2024年第7期1677-1709,共33页
Optimization algorithms play a pivotal role in enhancing the performance and efficiency of systems across various scientific and engineering disciplines.To enhance the performance and alleviate the limitations of the ... Optimization algorithms play a pivotal role in enhancing the performance and efficiency of systems across various scientific and engineering disciplines.To enhance the performance and alleviate the limitations of the Northern Goshawk Optimization(NGO)algorithm,particularly its tendency towards premature convergence and entrapment in local optima during function optimization processes,this study introduces an advanced Improved Northern Goshawk Optimization(INGO)algorithm.This algorithm incorporates a multifaceted enhancement strategy to boost operational efficiency.Initially,a tent chaotic map is employed in the initialization phase to generate a diverse initial population,providing high-quality feasible solutions.Subsequently,after the first phase of the NGO’s iterative process,a whale fall strategy is introduced to prevent premature convergence into local optima.This is followed by the integration of T-distributionmutation strategies and the State Transition Algorithm(STA)after the second phase of the NGO,achieving a balanced synergy between the algorithm’s exploitation and exploration.This research evaluates the performance of INGO using 23 benchmark functions alongside the IEEE CEC 2017 benchmark functions,accompanied by a statistical analysis of the results.The experimental outcomes demonstrate INGO’s superior achievements in function optimization tasks.Furthermore,its applicability in solving engineering design problems was verified through simulations on Unmanned Aerial Vehicle(UAV)trajectory planning issues,establishing INGO’s capability in addressing complex optimization challenges. 展开更多
关键词 northern Goshawk Optimization tent chaotic map T-distribution disturbance state transition algorithm UAV path planning
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Analysis on characteristics of extreme precipitation indices and atmospheric circulation in Northern Shanxi
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作者 Xia Cai Yan Song +3 位作者 Lin Cai Xin Su GuiHua Liang YanMing Xu 《Research in Cold and Arid Regions》 CSCD 2024年第2期84-97,共14页
This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020,and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average r... This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020,and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average reanalysis data.The study employs techniques such as empirical orthogonal function(EOF)decomposition,MannKendall mutation and other methods to investigate the spatiotemporal distribution of extreme precipitation index in northern Shanxi and their correlation with atmospheric circulation.The research results show that:the absolute index,relative index,intensity index and sustained dry period index(CDD)in the continuous index appear from southwest to northeast.The spatial distribution characteristics of the central region decrease,while the continuous wet period(CWD)decreases from the central to the east and west.The three indices Rx1day,Rx5day,and CWD mutated in 1978,1975,and 1983 respectively,and other extreme precipitation indices all appeared in a sudden change from a low-value period to a high-value period occurred around 2010.In the high-value years of the summer extreme precipitation index,there is a significant negative anomaly in the height field in the mid-high latitude regions of Eurasia.Northern Shanxi is controlled by a broad low-pressure trough in the Lake Baikal area.Water vapor transported via the east,west,and south routes converges in the northern Shanxi region and encounters cold air from the north.There is a strong upward motion anomaly at 500 hPa in the troposphere,and the dynamic conditions of upper-level divergence and lower-level convergence lead to more summer extreme precipitation in the northern Shanxi region.Conversely,in the low-value years of the summer extreme precipitation index,northern Shanxi is affected by a strong high-pressure ridge north of Lake Baikal.There is a downward motion anomaly at 500 hPa,and the northern Shanxi region lacks water vapor.The cold and warm air cannot converge,and both the water vapor conditions and dynamic conditions are poor,which is not conducive to the production of extreme precipitation in northern Shanxi. 展开更多
关键词 northern Shanxi Extreme precipitation indices Spatio-temporal distribution and evolution MUTATIONS Atmospheric circulation anomaly
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Depression&Anxiety Among Women in Northern Kenya:Sociodemographic Predictors
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作者 Gladys Kabura Mwangi 《Psychology Research》 2024年第2期57-63,共7页
This article documents socio-demographic predictors of anxiety and depression among Maasai women in resource poor settings in Northern Kenya.These findings emerged from the findings of a dissertation research that aim... This article documents socio-demographic predictors of anxiety and depression among Maasai women in resource poor settings in Northern Kenya.These findings emerged from the findings of a dissertation research that aimed to establish the treatment effectiveness of an eclectic model of psychoeducation(PE)in treating depressive and anxiety symptoms among the women.The study adopted a quasi-experimental research design which had an experimental group(EG)and control group(CG).The population for the study was 686 female members of Conservation Enterprise Groups(CEG)in Laikipia County,from which a sample of 200 were recruited for the study(EG,n=100 and CG,n=100),at 80%power and 30%effective size.The Beck’s Depression Inventory(BDI)and Beck’s Anxiety Inventory(BAI)tools were used to assess the symptoms of depression and anxiety,respectively.The PE was provided as an intervention treatment to the EG at the middle and end of the study,after which the respondents were tested for symptoms of depression.The study established the prevalence of depression as 26.7%and 31.3%for anxiety and disorders,among women in the region.Data was analyzed using SPSS Version 21.0. 展开更多
关键词 SOCIODEMOGRAPHIC ANXIETY DEPRESSION PREDICTORS Maasai women northern Kenya
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Earthquake detection probabilities and completeness magnitude in the northern margin of the Ordos Block
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作者 Zhang Fan Yang Xiao-Zhong Cui Feng-Zhi 《Applied Geophysics》 SCIE CSCD 2024年第4期777-793,881,共18页
The assessment of the completeness of earthquake catalogs is a prerequisite for studying the patterns of seismic activity.In traditional approaches,the minimum magnitude of completeness(MC)is employed to evaluate cata... The assessment of the completeness of earthquake catalogs is a prerequisite for studying the patterns of seismic activity.In traditional approaches,the minimum magnitude of completeness(MC)is employed to evaluate catalog completeness,with events below MC being discarded,leading to the underutilization of the data.Detection probability is a more detailed measure of the catalog's completeness than MC;its use results in better model compatibility with data in seismic activity modeling and allows for more comprehensive utilization of seismic observation data across temporal,spatial,and magnitude dimensions.Using the magnitude-rank method and Maximum Curvature(MAXC)methods,we analyzed temporal variations in earthquake catalog completeness,finding that MC stabilized after 2010,which closely coincides with improvements in monitoring capabilities and the densification of seismic networks.Employing the probability-based magnitude of completeness(PMC)and entire magnitude range(EMR)methods,grounded in distinct foundational assumptions and computational principles,we analyzed the 2010-2023 earthquake catalog for the northern margin of the Ordos Block,aiming to assess the detection probability of earthquakes and the completeness of the earthquake catalog.The PMC method yielded the detection probability distribution for 76 stations in the distance-magnitude space.A scoring metric was designed based on station detection capabilities for small earthquakes in the near field.From the detection probabilities of stations,we inferred detection probabilities of the network for diff erent magnitude ranges and mapped the spatial distribution of the probability-based completeness magnitude.In the EMR method,we employed a segmented model fitted to the observed data to determine the detection probability and completeness magnitude for every grid point in the study region.We discussed the sample dependency and low-magnitude failure phenomena of the PMC method,noting the potential overestimation of detection probabilities for lower magnitudes and the underestimation of MC in areas with weaker monitoring capabilities.The results obtained via the two methods support these hypotheses.The assessment results indicate better monitoring capabilities on the eastern side of the study area but worse on the northwest side.The spatial distribution of network monitoring capabilities is uneven,correlating with the distribution of stations and showing significant diff erences in detection capabilities among diff erent stations.The truncation eff ects of data and station selection aff ected the evaluation results at the edges of the study area.Overall,both methods yielded detailed descriptions of the earthquake catalog,but careful selection of calculation parameters or adjustments based on the strengths of diff erent methods is necessary to correct potential biases. 展开更多
关键词 magnitude of completeness northern margin of the Ordos Block PMC method EMR method earthquake detection probability
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Differential scavenging behavior of anthropogenic Pb revealed by sediment traps in the northern South China Sea basin
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作者 Weiying Li Jingjing Zhang +6 位作者 Hongliang Li Shuh-Ji Kao Zezhou Wu Xingju He Lihua Ran Martin G.Wiesner Jianfang Chen 《Acta Oceanologica Sinica》 CSCD 2024年第11期26-33,共8页
Trace metals emitted from human activities may have penetrated into the deep seas,and the underlying control mechanisms remain poorly understood.Sinking particles collected by moored time-series sediment traps from th... Trace metals emitted from human activities may have penetrated into the deep seas,and the underlying control mechanisms remain poorly understood.Sinking particles collected by moored time-series sediment traps from the northern South China Sea(NSCS)basin showed significant enrichment of anthropogenic aerosol Pb relative to lithogenic Fe.Total mass flux was primarily driven by seasonal primary production,and significant positive correlations were found between Pb/Fe flux and major biogenic components,indicating the crucial role of the biological pump in Pb/Fe scavenging in the water column.Notably,Pb exhibited 30−50 times higher affinity to biogenic components than Fe.A comparison was made between the enrichment factors of Fe and Pb in aerosols,euphotic particles,and sinking particles,which revealed that Pb exhibited significantly higher particle reactivity than Fe.This higher particle reactivity may encompass processes such as adsorption/desorption,bioaccumulation and decomposition release.The differential scavenging behavior of Pb suggested that the majority of Pb was rapidly scavenged in the euphotic zone and was preferentially released for accumulation in the twilight zone.This accumulation may further outflow through the Luzon Strait and result in the high dissolved Pb concentration observed in the subsurface water columns in both the NSCS and western Pacific Ocean.The rest of anthropogenic Pb in sinking particles tended to penetrate into deeper water layers and continue to be released below the twilight zone.These findings provide new insights into the biogeochemical cycling of trace metals originating from anthropogenic aerosols in marginal seas and serve as an example of the fate of other anthropogenic atmospheric pollutants. 展开更多
关键词 anthropogenic aerosol Pb sinking particle biological pump northern South China Sea
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Analysis and prediction of glacier evolution trend(2020-2100)in Northern Xinjiang
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作者 Xi-yong Sun Yang Jiao +5 位作者 Qian-li Ma Jing-hui Fan Xiao-min Du Jia-feng Liu Shao-qiang Wang Wen-chen Hu 《China Geology》 CAS CSCD 2024年第4期661-671,共11页
Glaciers,as“solid reservoirs”,are precious resources in arid areas.The study of glaciers is of great significance to the sustainable development and management of agriculture and the economy in northern Xinjiang.The... Glaciers,as“solid reservoirs”,are precious resources in arid areas.The study of glaciers is of great significance to the sustainable development and management of agriculture and the economy in northern Xinjiang.The area of glacier distribution on the 1963 topographic map data,1975 MSS data,2000 ETM data,2008 CBERS-2 data,2014 and 2018 ETM+were collected as secondary data.According to the remote sensing survey,the glacier areas in Northern Xinjiang are identified during 1963-2018.Based on the evolution of glacier area in the past 55 years,and using two scenarios,the average annual decrease area of a region during the whole 1963-2018 and the period with the minimum reduction area,the glacier areas of Southern Tianshan Mountains,Western Tianshan Mountains,Eastern Tianshan Mountains,the Sawuer Mountains and Altai Mountains in Northern Xinjiang,and the whole northern Xinjiang in 2030,2040,2050,and 2100 are examined and predicted.In 2100,the glacier area in Northern Xinjiang may decrease by 43%-59%. 展开更多
关键词 Glacial evolution Glacial area Global warm Trend analysis Glacial disappear Environmental change northern Xinjiang Altai Mountains of Central Asia
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Spatial and Temporal Analysis of Maximum and Minimum Temperature Trends in Northern Sudan during (1990-2019)
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作者 Elhag Gamreldin Monzer Hamadalnel 《Journal of Geoscience and Environment Protection》 2024年第5期266-288,共23页
The study addresses an urgent and globally significant issue of climate change by focusing on the detailed spatial and temporal analysis of temperature trends in Northern Sudan. It fills a critical research gap by pro... The study addresses an urgent and globally significant issue of climate change by focusing on the detailed spatial and temporal analysis of temperature trends in Northern Sudan. It fills a critical research gap by providing localized data over a substantial period (1990-2019), which could help in understanding the nuanced impacts of climate change in Sahel regions like Northern Sudan. In addition, the comprehensive coverage of both spatial and temporal dimensions, supported by a substantial dataset from five meteorological stations, provides a thorough understanding of the subject area. The utilization of robust statistical methods (Mann-Kendall test and Sen’s slope analysis) for analyzing temperature trends adds scientific rigor and credibility to the findings. Our results reveal a consistently increasing trend in maximum temperatures across most stations, particularly during the hot season (AMJ). However, the wet season (JAS) shows high maximum temperatures but no significant trend. Moreover, significant increasing trends in minimum temperatures were observed in all stations except Abu Hamed, where the trend, although increasing, did not reach statistical significance during the hot and cold seasons, and the coldest temperatures were observed during the cold season. These findings underscore the complex temperature dynamics in Northern Sudan and highlight the need for continued monitoring and adaptive measures in response to ongoing climate changes in the region. 展开更多
关键词 Climate Change northern Sudan Temperature Trend Seasonal Analysis
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Optimizing Power Flow in Northern Cameroon’s Interconnected Grid: Challenges and Solutions
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作者 Jean Ndoumbe Ivan Basile Kabeina +1 位作者 Michael Koumbou Piembe Martin Ndjock 《Journal of Power and Energy Engineering》 2024年第9期63-83,共21页
This paper presents an analysis of the power flow within the Northern Interconnected Grid of Cameroon. The Newton-Raphson method has been performed, known for its accuracy, under MATLAB software, to model and solve co... This paper presents an analysis of the power flow within the Northern Interconnected Grid of Cameroon. The Newton-Raphson method has been performed, known for its accuracy, under MATLAB software, to model and solve complex power flow equations. This study simulates a series of outage scenarios to evaluate the responsiveness of the grid. The results obtained underline the crucial importance of reactive power management and highlight the urgent need to consolidate the grid infrastructure of North Cameroon. To increase grid resilience and stability, the paper recommends the strategic integration of renewables and the development of interconnections with other power grids. These measures are presented as viable solutions to meet current and future energy distribution challenges, ensuring a reliable and sustainable power supply for Cameroon. 展开更多
关键词 Power Flow northern Interconnected Grid NEWTON-RAPHSON MATLAB Grid Stability
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