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Paleoclimate,paleoenvironment and source rock development model of Eocene in Shunde Sag,Pearl River Mouth Basin,China 被引量:1
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作者 PEI Jianxiang JIN Qiuyue +1 位作者 FAN Daijun LEI Mingzhu 《Petroleum Exploration and Development》 2025年第2期346-360,共15页
Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions... Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions,and modeling of the source rocks in the second member of the Eocene Wenchang Formation(Wen 2 Member)in the Northern Shunde Subsag at the southwestern margin of the Pearl River Mouth Basin.The Wen 2 Member hosts excellent,thick lacustrine source rocks with strong longitudinal heterogeneity and an average total organic carbon(TOC)content of over 4.9%.The Wen 2 Member can be divided into three units(I,II,III)from bottom to top.Unit I features excellent source rocks with Type I organic matters(average TOC of 5.9%)primarily sourced from lake organisms;Unit II hosts source rocks dominated by Type II2 organic matters(average TOC of 2.2%),which are originated from mixed sources dominated by terrestrial input.Unit III contains good to excellent source rocks dominated by Type II1 organic matters(average TOC of 4.9%),which are mainly contributed by lake organisms and partially by terrestrial input.Under the background of rapid subsidence and limited source supply during intense rifting period in the Eocene,excellent source rocks were developed in Wen 2 Member in the Northern Shunde Subsag under the coordinated control of warm and humid climate,volcanic activity,and deep-water reducing conditions.During the deposition of Unit I,the warm and humid climate and volcanic activity promoted the proliferation of lake algaes,primarily Granodiscus,resulting in high initial productivity,and deep-water reducing conditions enabled satisfactory preservation of organic matters.These factors jointly controlled the development and occurrence of excellent source rocks.During the deposition of Unit II,a transition from warm to cool and semi-arid paleoclimatic conditions led to a decrease in lake algaes and initial productivity.Additionally,enhanced terrestrial input and shallow-water,weakly oxidizing water conditions caused a significant dilution and decomposition of organic matters,degrading the quality of source rocks.During the deposition of Unit III,when the paleoclimatic conditions are cool and humid,Pediastrum and Botryococcus began to thrive,leading to an increase in productivity.Meanwhile,the reducing environment of semi-deep water facilitated the preservation of excellent source rocks,albeit slightly inferior to those in Unit I.The study results clarify the differential origins and development models of various source rocks in the Shunde Sag,offering valuable guidance for evaluating source rocks and selecting petroleum exploration targets in similar marginal sags. 展开更多
关键词 Pearl River Mouth Basin Shunde Sag Northern Shunde Subsag marginal sag Paleogene Eocene Wenchang Formation PALAEOCLIMATE PALAEOENVIRONMENT source rock development model
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Marginal Selenium Deficiency Alternates Inflammatory Response through NF-κB Pathway in LPS-induced Mouse Mastitis Model
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作者 Zhang Yixin Sun Qiaochu +3 位作者 Luo Tianning Zhang Huayu Wang Fucheng Zhang Wen 《Journal of Northeast Agricultural University(English Edition)》 2025年第2期37-46,共10页
The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se ... The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se deficiency accusers more frequently in low-Se regions.Therefore,to investigate the Se status and inflammatory response of the mammary gland under marginal dietary Se levels,an lipopolysaccharide(LPS)induced mouse mastitis model was established.Mice were fed with moderate Se diet(0.087 mg•kg^(-1) Se),adequate Se diet(0.15 mg•kg^(-1) Se)or excessive Se diet(1.5 mg•kg^(-1) Se)for 60 days.Se status and inflammatory factors were investigated.Results showed that the Se status of mammary gland correlated with dietary Se levels.Marginal Se deficiency exacerbated mammary tissue histopathology;increased the mRNA level of inflammatory genes tumor necrosis factor alpha(TNF-α),interleukin-1β(IL-1β)and cyclooxygenase-2(COX-2);and enhanced the phosphorylation of NF-κB p65 in mammary gland tissues.Supplementation of Se in diet higher than recommended levels reduced the inflammatory reaction of mammary glands in LPS-induced mastitis model and provided a protective effect. 展开更多
关键词 MARGINAL selenium deficiency MASTITIS INFLAMMATION NF-κB signal pathway
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Gastrointestinal bleeding after pancreatoduodenectomy:Report of four cases
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作者 Zi-Jin Liu Jia-Yi Hong +2 位作者 Chao Zhang Jing She Hui-Hong Zhai 《World Journal of Gastrointestinal Surgery》 2025年第1期290-297,共8页
BACKGROUND Postpancreatectomy hemorrhage is one of the most severe and life-threatening complications after pancreaticoduodenectomy.We present four cases of gastrointestinal bleeding patients to clarify its appropriat... BACKGROUND Postpancreatectomy hemorrhage is one of the most severe and life-threatening complications after pancreaticoduodenectomy.We present four cases of gastrointestinal bleeding patients to clarify its appropriate treatment and prevention.CASE SUMMARY The main symptoms included black stool,hematochezia,haematemesis,blood in the nasogastric tube,and hemorrhagic shock.The mean age was 66.25 years old and the median onset time was 340 d after the surgery.The bleeding location comprised gastrointestinal anastomosis,bile duct-jejunum anastomosis,and extraluminal bleeding.The possible causes included marginal ulcer,jejunal varix,and abdominal infection.Endoscopic hemostatic clips,as well as a covered stent using angiography,were utilized to stop the bleeding and three patients survived.Only one patient died of gastrointestinal bleeding,abdominal bleeding,abdominal infection,hypovolemic shock,and disseminated intravascular coagulation.CONCLUSION Early and effective endoscopic intervention is the key to successful hemostasis in patients with gastrointestinal bleeding after pancreatoduodenectomy. 展开更多
关键词 Postpancreatectomy hemorrhage PANCREATICODUODENECTOMY Marginal ulcer Gastrointestinal bleeding Case report
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Deep-water Natural Gas Differential Migration and Enrichment in East African Transform Continental Marginal Basins
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作者 CAI Jun HE Youbin +1 位作者 LIANG Jianshe GUO Rong 《Acta Geologica Sinica(English Edition)》 2025年第4期1105-1118,共14页
Compared to discrete continental marginal basins,the mechanisms of hydrocarbon migration and enrichment in transform continental marginal basins are poorly understood.In this study,we conducted a comprehensive analysi... Compared to discrete continental marginal basins,the mechanisms of hydrocarbon migration and enrichment in transform continental marginal basins are poorly understood.In this study,we conducted a comprehensive analysis of the main source rocks,reservoirs,and vertical migration pathways within the Rovuma(RB)and Tanzania(TB)basins in East Africa utilizing drilling,logging,seismic,and geochemical data.The results indicate that the enhanced preservation conditions of the Lower Jurassic source rocks in the southwest could lead to the discovery of large natural gas fields in the southern TB and RB.The primary reservoir is a deep-water turbidite sandstone.Due to topographic differences,the expanse of the turbidite sandstones in the RB is significantly larger than those in Tanzania.The main vertical migration pathways are the western boundary fault zone of the Kerimbas Graben(WBFZ)and the Seagap fault zone(SFZ).In the RB,natural gas migrates vertically along the WBFZ and preferentially accumulates in the deep-water turbidite sandstones of the footwall under the control of the fluid potential.Conversely,in the southern TB,the deep natural gas first migrates upward along the SFZ,then moves along the shallow branch faults in the sandstones on both sides of the SFZ. 展开更多
关键词 upstream exploration natural gas differential enrichment transform continental marginal basin fault activity DEEP-WATER Mozambique-Tanzania
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Quantum algorithm for marginal Fisher analysis
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作者 Jing Li Yanqi Song +2 位作者 Sujuan Qin Wenmin Li Fei Gao 《Chinese Physics B》 2025年第12期40-51,共12页
Marginal Fisher analysis(MFA)stands out as a prominent dimensionality reduction algorithm,striving to minimize within-class scatter while maximizing the separability between marginal data points.However,MFA and its va... Marginal Fisher analysis(MFA)stands out as a prominent dimensionality reduction algorithm,striving to minimize within-class scatter while maximizing the separability between marginal data points.However,MFA and its variants require substantial computational resources when dealing with large-scale data.To address this,we propose quantum algorithms for MFA(called QMFA).QMFA is composed of two core processes:the first is the efficient construction of the weight matrices for the intrinsic and penalty graphs,and the second is solving the generalized eigenvalue problem(GEP)using the block-encoding technique.Compared to classical MFA,the proposed QMFA achieves a polynomial acceleration in the number of samples and exponential acceleration in the dimensionality.Additionally,we investigate quantum algorithms for different variants of MFA.Specifically,for enhanced MFA and multiple MFA,we address the construction of the related weight matrix,which differs from that in standard MFA.For kernel MFA,we solve the GEP associated with the corresponding kernel matrix.The proposed quantum algorithms achieve a speedup equivalent to that of QMFA. 展开更多
关键词 quantum machine learning block-encoding dimensionality reduction marginal Fisher analysis graph construction
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Folic acid ameliorates the immunogenicity of PEGylated liposomes
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作者 Xiying Wu Anze Liu +2 位作者 Yuzhong Yan Ying Lu Huan Wang 《Chinese Chemical Letters》 2025年第6期310-313,共4页
As PEGylated liposomes have witnessed remarkable advancements in drug delivery,their immunogenicity has emerged as a notable challenge.In this study,we discovered that a simple pre-injection of folic acid(FA)effective... As PEGylated liposomes have witnessed remarkable advancements in drug delivery,their immunogenicity has emerged as a notable challenge.In this study,we discovered that a simple pre-injection of folic acid(FA)effectively mitigated the immunogenicity of PEGylated liposomes and enhanced their in vivo performance by tolerating splenic marginal zone B cells.FA specifically inhibited the internalization of PEGylated liposomes by splenic marginal zone B cells,thereby reducing splenic lymphocyte proliferation and specific IgM secretion.This modulation alleviated Ig M-mediated accelerated blood clearance and adverse accumulation of the PEGylated liposomes in the skin.These findings provide new insights into the immunomodulatory effects of FA and promising avenues to enhance the efficacy and safety of PEGylated liposomal nanomedicines. 展开更多
关键词 Folic acid Pegylated liposomes IMMUNOGENICITY Marginal zone B cells Accelerated blood clearance
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Predictors of survival in gastric mucosa-associated lymphoid tissue lymphoma:An updated surveillance,epidemiology,and end resultsbased analysis of age and gender disparities
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作者 Ayrton I Bangolo Khaled Sharaan +16 位作者 Behzad Amoozgar Shruti Wadhwani Lili Zhang Nikita Wadhwani Vignesh K Nagesh Jay Mehta Rishabh Goyal Gia DeRose Sarvarinder Gill Courtney Christoforo Swapnika Mallipeddi Selbin Boban Shubham Madan Budoor Alqinai Timophyll YH Fong Simcha Weissman Pierre Fwelo 《World Journal of Clinical Oncology》 2025年第6期153-163,共11页
BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma is a subtype of extranodal marginal zone lymphoma,typically occurring in mucosal sites such as the stomach,salivary glands,and lungs.This study aims to analyz... BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma is a subtype of extranodal marginal zone lymphoma,typically occurring in mucosal sites such as the stomach,salivary glands,and lungs.This study aims to analyze the demographic and clinicopathologic characteristics of patients with gastric MALT lymphoma in the United States and evaluate the interaction between age and gender on survival outcomes.AIM To analyze the demographic and clinicopathologic characteristics of patients with gastric MALT lymphoma in the United States and evaluate the interaction between age and gender on survival outcomes.METHODS A retrospective cohort study was conducted using the Surveillance,Epidemiology,and End Results(SEER)database,which included 2453 patients diagnosed with MALT lymphoma from 2010 to 2021.Data were analyzed for demographic factors,tumor characteristics,treatment modalities,and survival outcomes.A Cox proportional hazards regression model was used to identify predictors of overall mortality and cancer-specific mortality.RESULTS The study predominantly included Non-Hispanic White patients(62.78%),with nearly equal gender distribution(50.31%females,49.69%males),and most diagnoses occurring in individuals aged 60-79 years.The majority of tumors were localized(80.07%).Multivariate analysis identified older age,male gender,advanced tumor stage,and socioeconomic factors—such as annual income and marital status—as independent predictors of mortality.No significant interaction between age and gender on mortality outcomes was observed.CONCLUSION Sociodemographic factors,including advanced age,male gender,annual income,and marital status,as well as advanced tumor stage,significantly impacted survival outcomes in patients with MALT lymphoma.Radiotherapy was associated with a reduction in overall mortality.Early detection is crucial for optimizing outcomes,as localized disease responds well to available treatment modalities. 展开更多
关键词 Mucosa-associated lymphoid tissue lymphoma Extranodal marginal zone lymphoma MORTALITY Gastrointestinal cancer
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Fusion of deep learning and machine learning methods for hourly locational marginal price forecast in power systems
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作者 Matin Farhoumandi Sheida Bahramirad +5 位作者 Ahmed Alabdulwahab Mohammad Shahidehpour Farrokh Rahimi Ali Ipakchi Farrokh Albuyeh Sasan Mokhtari 《iEnergy》 2025年第3期193-204,共12页
In this paper,we propose STPLF,which stands for the short-term forecasting of locational marginal price components,including the forecasting of non-conforming hourly net loads.The volatility of transmission-level hour... In this paper,we propose STPLF,which stands for the short-term forecasting of locational marginal price components,including the forecasting of non-conforming hourly net loads.The volatility of transmission-level hourly locational marginal prices(LMPs)is caused by several factors,including weather data,hourly gas prices,historical hourly loads,and market prices.In addition,variations of non-conforming net loads,which are affected by behind-the-meter distributed energy resources(DERs)and retail customer loads,could have a major impact on the volatility of hourly LMPs,as bulk grid operators have limited visibility of such retail-level resources.We propose a fusion forecasting model for the STPLF,which uses machine learning and deep learning methods to forecast non-conforming loads and respective hourly prices.Additionally,data preprocessing and feature extraction are used to increase the accuracy of the STPLF.The proposed STPLF model also includes a post-processing stage for calculating the probability of hourly LMP spikes.We use a practical set of data to analyze the STPLF results and validate the proposed probabilistic method for calculating the LMP spikes. 展开更多
关键词 Locational marginal price forecasting machine learning deep learning non-conforming net loads probability of price spikes
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RDV Protonic Activation for EOR in Active,Mature Reservoirs and Marginal Wells
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作者 William J.Jimenez Carlos A.Rivera +1 位作者 Hector J.Sulvaran Hernan O.Gonzalez 《Journal of Energy and Power Engineering》 2025年第4期133-140,共8页
This study documents pioneering results in marginal wells in Texas,where the application of RDV-00■restored production through delayed protonic activation catalyzed by reservoir energy.The product,based on RDV■(Vaso... This study documents pioneering results in marginal wells in Texas,where the application of RDV-00■restored production through delayed protonic activation catalyzed by reservoir energy.The product,based on RDV■(Vasoactive Dynamic Reactor)technology,operates via:Controlled protonation of molecular structures;Release of energetic carbocations;Autonomous transformation without external inputs.(a)Case 1(Well#E2-Starr County):Certified as“dry”by RRC(2022)after 48 months at 0 BPD;8 months post-injection of 5 gal RDV-00■(Fluid column:37 bbl;Wellhead pressure:80 psi(vs.0 psi initially)).(b)Case 2(Well#P1-Luling Field):Historical stripper well(0.25-0.5 BPD);23 months of immobilization with 15 gal RDV-00■;Critical results:(1)Initial production:42 BPD(8,400%above baseline);(2)Shut-in wellhead pressure:40 psi(neighboring wells=0-3 psi);(3)Current behavior:Continuous recharge from reservoir(well shut-in due to lack of storage).(c)Technically Significant Observations:(1)First case of self-sustaining reactivation in depleted wells;(2)Mechanism validated by Autonomous pressure generation(0→40-80 psi),and Continuous flow without additional stimulation;(3)No documented precedents in SPE/OnePetro literature to our knowledge. 展开更多
关键词 Enhanced recovery marginal wells protonic activation CARBOCATIONS RDV-00■ autogenous pressure viscoactive rheology delayed activation autonomous EOR(enhanced oil recovery)
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Clinicopathologic features of 89 patients with lacrimal gland prolapse
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作者 Yu-Yao Qu Le Dong +7 位作者 Ya-Guang Hu Ning Gao Jing-Ming Li Qiao-Chu Cheng Shan Gao Ting Wei Jian-Min Ma Wan-Hu Zhang 《International Journal of Ophthalmology(English edition)》 2025年第6期1011-1015,共5页
AIM:To analyze the clinical and pathological features of 89 patients presenting as lacrimal gland prolapse(LGP).METHODS:This retrospective study included 89 patients presenting as LGP.Magnetic resonance imaging(MRI)sc... AIM:To analyze the clinical and pathological features of 89 patients presenting as lacrimal gland prolapse(LGP).METHODS:This retrospective study included 89 patients presenting as LGP.Magnetic resonance imaging(MRI)scan was performed for all patients.Pathology and immunohistochemical staining of prolapsed tissue were performed during the surgery.The histopathological subtype was obtained,and the related clinical manifestations of different subtype were marked.RESULTS:Among the 89 patients involved,the histopathological subtype includes dacryoadenitis(43%;n=38),focal lymphocytes infiltration(20%;n=18),immunoglobulin G4(IgG4)-related lacrimal gland inflammatory disease(15%;n=13),lacrimal gland(13%;n=12),and extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue(9%;n=8).As for manifestations of different subtypes,eyelid swelling was found the most frequent of lymphocytes infiltration(44%,n=8),and palpable lacrimal gland mass of dacryoadenitis(55%,n=21).All the IgG4-related lacrimal gland inflammatory disease(100%,n=13)and most dacryoadenitis(97%,n=37)presented as bilateral.CONCLUSION:LGP has the histopathological subtype most commonly as inflammation,followed by structural and lymphoproliferative changes.Most of patients present as eyelid swelling.Clinical manifestations can be significant to differentiate the diagnosis. 展开更多
关键词 lacrimal gland prolapse clinicopathologic features DACRYOADENITIS IgG4-related lacrimal gland inflammatory disease extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue
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Temporal-Spatial Variances of Holocene Precipitation at the Marginal Area of the East Asian Monsoon Influences from Pollen Evidence 被引量:6
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作者 刘鸿雁 崔海亭 +1 位作者 田育红 徐丽宏 《Acta Botanica Sinica》 CSCD 2002年第7期864-871,共8页
The woodland-steppe ecotone in the. southern Nei Mongol Plateau is located at the northern edge of the east Asian monsoon influences. A marked southeastern - northwestern (SE - NW) precipitation gradient exists in thi... The woodland-steppe ecotone in the. southern Nei Mongol Plateau is located at the northern edge of the east Asian monsoon influences. A marked southeastern - northwestern (SE - NW) precipitation gradient exists in this region. Quantitative reconstruction of palaeo-precipitation of this region is helpful to reveal the development of monsoon climate and to predict die future desertification. Based on modern vegetation and surface pollen studies, a pollen-precipitation transfer function in the study region was established. Pollen data from three sediment sequences within the ecotone were used to reconstruct palaeo-precipitation during the Holocene. The processes of precipitation changes in the three sequences were quite different. There was a tendency of precipitation declined from the onset of the Holocene to 1 100 a BP in Haoluku. But, in Liuzhouwan and Xiaoniuchang, both located south of Haoluku, the annual precipitation reached highest values during 7 800 - 6 200 a BP and 7 200 - 5 000 a BP, respectively. The influences of southwestern (SW) monsoon and the variances of topographical conditions have possibly caused these temporal-spatial variances. 展开更多
关键词 marginal area of the monsoon climate WOODLAND steppe ecotone Nei Mongol Plateau pollen-climate transfer function
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Modeling household car ownership using ordered logistic regression model 被引量:3
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作者 邓一凌 过秀成 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期500-505,共6页
Considering both the discrete and ordered nature of the household car ownership an ordered logistic regression model to predict household car ownership is established by using the data of Nanjing Household Travel Surv... Considering both the discrete and ordered nature of the household car ownership an ordered logistic regression model to predict household car ownership is established by using the data of Nanjing Household Travel Survey in the year 2012. The model results show that some household characteristics such as the number of driver licenses household income and home location are significant.Yet the intersection density indicating the street patterns of home location and the dummy near the subway and the bus stop density indicating the transit accessibility of home location are insignificant.The model estimation obtains a good γ2 the goodness of fit of the model and the model validation also shows a good performance in prediction.The marginal effects of all the significant explanatory variables are calculated to quantify the odds change in the household car ownership following a one-unit change in the explanatory variables. 展开更多
关键词 household car ownership ordered logisticregression model marginal effect household characteristics neighborhood characteristics
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Comparative study of Anaplasma parasites in tick carrying buffaloes and cattle 被引量:2
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作者 RAJPUT Z.I. 胡松华 +2 位作者 ARIJO A.G. HABIB M. KHALID M. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第11期1057-1062,共6页
A comparative study on the prevalence of Anaplasma parasite was conducted on ticks carrying buffaloes and cattle. Five hundred blood samples of both animals (250 of each) were collected during February, March and Apri... A comparative study on the prevalence of Anaplasma parasite was conducted on ticks carrying buffaloes and cattle. Five hundred blood samples of both animals (250 of each) were collected during February, March and April. Thin blood smears on glass slides were made, fixed in 100% methyl alcohol and examined. Microscopic examination revealed that 205 (41%) animals had Anaplasma parasites, out of which 89, 44 and 72 animals had Anaplasma marginale, Anaplasma centrale and mixed infection respectively. Infected buffaloes and cattle were 75 and 130 respectively. The infection in female was 53 and 92 in buffaloes and cattle respectively. Twenty-two and 92 blood samples of male were found positive in buffaloes and cattle respectively. Com- parative study revealed that the cattle were 26.82% more susceptible than buffaloes. The parasite prevailing percentage in female of both animals was slightly higher than that of the male. This investigation was aimed at studying the comparative prevalence of Anaplasma parasite in tick carrying buffaloes and cattle. 展开更多
关键词 Anaplasma marginale Anaplasma centrale BUFFALOES CATTLE TICKS
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海外华人纪录片中的“边缘人” 被引量:2
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作者 江霄 焦道利 《青年记者》 北大核心 2015年第20期56-57,共2页
"边缘人"(marginal man)是美国社会学家帕克在考察芝加哥的城市生态工作时提出的概念,用来指生活在两个不同的世界、对两个世界都陌生的人,他们也是"文化混血儿",是在未完全相融的文化边缘生活的个体。这个概念标示着人们由于文... "边缘人"(marginal man)是美国社会学家帕克在考察芝加哥的城市生态工作时提出的概念,用来指生活在两个不同的世界、对两个世界都陌生的人,他们也是"文化混血儿",是在未完全相融的文化边缘生活的个体。这个概念标示着人们由于文化差异而形成的交流障碍,也标示着某种跨文化关系。有意味的是,从事跨文化传播研究的人大多与某种"边缘人"的经验相关联:或者漫游于各种文化边缘, 展开更多
关键词 边缘人 文化特征 跨文化传播 全相 MARGINAL 城市生态 帕克 文化学家 中国工人 交流障碍
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Effects of Sowing Rate on Marginal Superiority and Yield of Wheat in Wheat-cotton Intercropping System
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作者 王树林 祁虹 +4 位作者 王燕 张谦 冯国艺 林永增 梁青龙 《Agricultural Science & Technology》 CAS 2015年第12期2649-2652,共4页
In the wheat-cotton intercropping system, total 6 sowing rates (187.5, 225.0, 262.5, 300.0, 337.5 and 375.0 kg/hm2) were arranged, and the effects of sowing rate on marginal superiority and yield of wheat were inves... In the wheat-cotton intercropping system, total 6 sowing rates (187.5, 225.0, 262.5, 300.0, 337.5 and 375.0 kg/hm2) were arranged, and the effects of sowing rate on marginal superiority and yield of wheat were investigated. The re- sults showed that the effect of sowing rate on inner-line wheat was greater than that on side-line wheat; with the increased sowing rate, the marginal superiority of panicle number was reduced in overall, and the difference in panicle number be- tween inner and side lines was decreased from 9.0×10^5/hm2 (sowing rate of 187.5 kg/hm2) to 7.8×10^5/hm2 (sowing rate of 375.0 kg/hm2); the marginal superiority of grains per spike was increased first and then reduced, and the largest difference in grains per spike between the inner and side lines reached 4.6 under the sowing rate of 300.0 kg/hm2; the marginal superiority of 1 000-grain weight and yield was gradually increased, and the largest difference in 1 000-grain weight between the inner and side lines reached 3.9 g under the sowing rate of 337.5 kg/hm2, and in yield reached 3 136.5 kg/hm2under the sowing rate of 375.0 kg/hm2. The effects of sowing rate on the three yield factors of intercropped wheat ranked as panicle number 〉 grains per spike 〉 1 000-grain weight. The appropriate sowing rate of wheat was 225.0-262.0 kg/hm2 in the wheat-cotton intercropping system. 展开更多
关键词 Wheat-cotton intercropping WHEAT Sowing rate Marginal superiority YIELD
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Analysis on Marginal Superiority and Yield of Different Wheat Varieties in Wheat-cotton Intercropping System
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作者 王树林 祁虹 +4 位作者 王燕 张谦 冯国艺 林永增 梁青龙 《Agricultural Science & Technology》 CAS 2016年第5期1077-1079,共3页
In wheat-cotton intercropping system,the spike number per unit area,grains per spike,thousand-grain weight and yield of side line and inner line were investigated in six wheat varieties to study the marginal superiori... In wheat-cotton intercropping system,the spike number per unit area,grains per spike,thousand-grain weight and yield of side line and inner line were investigated in six wheat varieties to study the marginal superiority and select suitable wheat varieties intercropped with cotton.The results showed that Xingmai No.4had obvious marginal superiority with the yield of 6 919.0 kg/hm2,so it was the suitable variety for wheat-cotton intercropping system. 展开更多
关键词 Wheat-cotton intercropping Wheat variety Marginal superiority
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Estimation in Nonlinear Models with Random Effects
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作者 宗序平 朱仲义 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期124-129,共6页
A necessary condition for existence of any weakly consistent estimator is presented in nonlinear models with random effects. Under mild regularity conditions, the strong consistency and the asymptotic normality of the... A necessary condition for existence of any weakly consistent estimator is presented in nonlinear models with random effects. Under mild regularity conditions, the strong consistency and the asymptotic normality of the estimator are proved. The results of Breslow and Calyton(1993), Lee and Nelder(1996) are improved. 展开更多
关键词 fixed effects random effects marginal likelihood
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Analyzing our educational resource deployment of compulsory education by marginal utility
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作者 高丽 程宝良 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2006年第S1期353-356,共4页
In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment ... In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment in ourcountry,gave some advice about howtoi mprove our educational resource deployment of compulsory education. 展开更多
关键词 marginal utility educational resource compulsory education
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对西点军校学生培训系统的建模分析
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作者 刘磊 高军 黄天辰 《科学技术与工程》 2006年第5期651-654,共4页
依据系统工程和相关管理原理,对西点军校培训系统进行了研究,从不同侧面构建了多个分析模型,为全面、准确地了解西点军校改革的思路和过程,并为我军军校建设与发展带来启发和借鉴,提供了一条有效的途径。
关键词 西点军校 改革 道斯矩阵 边际效用(Marginal utility) 企业过程再造(BPR)
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Productivity effect and overuse of pesticide in crop production in China 被引量:24
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作者 ZHANG Chao Guanming Shi +1 位作者 SHEN Jian HU Rui-fa 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1903-1910,共8页
Chinese farmers are often accused of overusing pesticides that play a crucial role in enhancing crop yield by reducing losses to crop pests. Pesticide overuse has caused a series of negative health and environmental e... Chinese farmers are often accused of overusing pesticides that play a crucial role in enhancing crop yield by reducing losses to crop pests. Pesticide overuse has caused a series of negative health and environmental externalities. This paper quantiifes the productivity effect and the optimal amount of pesticides in rice, cotton and maize production in China from the economic perspective. Using survey data col ected in 2012 and 2013, both Cobb-Douglas and Weibul damage control speciifcations are used to estimate the production function. Results show that pesticides have statistical y signiifcant pro-ductivity effect on crop yield. On the condition of Weibul damage control speciifcations, the marginal products of 1 kg of the active ingredients of pesticides for rice, cotton and maize are 71.06, 22.73 and 98.45 kg, respectively. However, 57, 64 and 17%of the actual amount of pesticides are overused for rice, cotton and maize, respectively. Moreover, the productivity effect of pesticides would be overestimated using Cobb-Douglas speciifcation without incorporating a damage control agent. 展开更多
关键词 productivity effect damage control agent pesticide overuse marginal product
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