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Research on the Behavior and Egg Fertilization Rate of Dwarf Layers and White Leghorn Chickens Fed in Floor-Rearing System
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作者 Long Liu Aiqiao Liu +3 位作者 Baogui Zhou Shoushan Du Peng Hai ZhonghuaNing 《Journal of Agricultural Science and Technology(A)》 2014年第1期86-92,共7页
Influenced by animal welfare requirements and expensive labor cost, producers tend to feed layers in non-cage system such as floor rearing. With the development of commercial lines of dwarf layers, the property of dwa... Influenced by animal welfare requirements and expensive labor cost, producers tend to feed layers in non-cage system such as floor rearing. With the development of commercial lines of dwarf layers, the property of dwarf layers' natural mating is drawing more and more attention. In this study, the authors hybridized Nongda Ill dwarf layers with White Leghorn chickens in floor-rearing system to research whether dwarf layers had defect in natural mating. Two steps of experiments were performed. The authors detected the fertilization rate of collected eggs, observed chickens' behavior in step I when a hen from other group was suddenly put into and recorded copulation number of every group in step II from 7:30 to 19:30. The results indicated that drawf cocks were as good as Leghorn cocks in natrual mating under floor-rearing system while drawf hens were better than Leghorn hens. Observation results showed no difference on reaction to intermixed hens between drawf layers and Leghorn layers. The best proportion of male to female for drawf layers was 1:8 in this experiment and dwarf cocks tended to mate dwarf hens rather than Leghorn hens. 展开更多
关键词 Dwarf layer BEHAVIOR natural mating fertilization rate floor-rearing.
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Response of Saline-alkali Cropland Soil CO_(2)Fluxes to Nitrogen Fertilization,Irrigation and Temperature via DAYCENT Modeling
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作者 Peng ZHANG Hanxiao FENG +2 位作者 Liming LAI Haiwei WANG Yang YANG 《Agricultural Biotechnology》 2025年第3期56-63,共8页
A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying sc... A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying scenarios including nitrogen fertilization rates,irrigation rates,and air temperatures in the Hetao Irrigation District(HID)over the 38-year period.DAYCENT model was used to predict carbon dioxide(CO_(2))fluxes from cultivated soils in the HID,Inner Mongolia from^(2)023 to 2060(the year of achieving the"carbon neutrality"goal)in this study.Results showed that mean soil CO_(2)fluxes in the sunflower field[1035.13 g/(m^(2).yr)]were significantly lower than those in the maize field[1405.54 g/(m^(2).yr)].An increase in nitrogen fertilization rate led to a significant escalation in soil CO_(2)fluxes.Moreover,elevating irrigation rates for washing salts by irrigation(WSBI)diminished soil CO_(2)fluxes in the sunflower field while amplifying them in the maize field.A rise in air temperature resulted in an increase in soil CO_(2)fluxes from the maize field,with annual increases observed,but a reduction in soil CO_(2)fluxes from the sunflower field.The sunflower fields in the HID have a more substantial advantage than the corn fields in mitigating soil CO_(2)emissions. 展开更多
关键词 Soil CO_(2)flux Nitrogen fertilization rate SUNFLOWER Washing salts by irrigation Rising temperature DAYCENT model Hetao Irrigation District
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Nitrogen and Phosphorus Runoff Losses from Orchard Soils in South China as Affected by Fertilization Depths and Rates 被引量:26
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作者 ZENG Shu-Cai SU Zhi-Yao +2 位作者 CHEN Bei-Guang WU Qi-Tang OUYANG Ying 《Pedosphere》 SCIE CAS CSCD 2008年第1期45-53,共9页
Fertilizers are heavily applied in orchards of the hilly and mountainous topography of South China and may increase nutrient loadings to receiving waters.A simple runoff collecting system was used to measure the effec... Fertilizers are heavily applied in orchards of the hilly and mountainous topography of South China and may increase nutrient loadings to receiving waters.A simple runoff collecting system was used to measure the effects of different fertilization treatments on total N and P concentrations of surface runoff in a Chinese chestnut (Castanea mollissima Blume) orchard in Dongyuan County,Guangdong Province,China.In such orchards,fertilizer was typically applied in two short furrows or pits on either side of each tree.Treatments included three application depths (surface,10cm and 20 cm),and three application rates (low,median and high).Results showed that 90.5% of the runoff water samples had a total N concentration higher than 0.35 mgL^(-1) and 54.2% had a total P concentration higher than 0.1 mgL^(-1).Fertilizer application at all depths and at all but the lowest rate significantly increased total N and P concentrations in runoff water.Fertilization with chemical compound fertilizer at a soil depth of 20cm produced significantly lower (P<0.05) total N concentration in runoff than both surface and 10-cm depth fertilization,and significantly lower (P<0.05) total P concentration in runoff than surface fertilization.Total N and P concentrations in runoff significantly increased with the application rate of organic fertilizers.With the exception of total P concentrations,which were not significantly different between the control and fertilization at a rate of 119 kg P ha-1 in organic form,all the other fertilization treatments produced significantly higher total N and total P concentrations in runoff than the control.A fertilization depth≥20cm and an application rate≤72 kg N ha^(-1) or 119 kg P ha^(-1) for compound organic fertilizer was suggested to substantially reduce N and P runoff losses from hillslope orchards and to protect receiving waters in South China. 展开更多
关键词 fertilization depth fertilization rate RUNOFF total N total P
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Intracytoplasmic Sperm Injection Fertilization Rate Does Not-Depend on the Proportion of Round-headed Sperm, Small acrosomal Sperm, or Morphologically Normal Sperm in Patients with Partial Globozoospermia 被引量:3
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作者 Ling-Ying Jiang Ling-Yun Yang Xiao-Mei Tong Hai-Yan Zhu Ya-Mei Xue Wen-Zhi Xu Yang Yang Song-Ying Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第12期1590-1595,共6页
Background:Generally,intracytoplasmic sperm injection (ICSI) may be the preferable method to treat partial globozoospermia,but whether there exist some correlations between ICSI fertilization rate and the proportio... Background:Generally,intracytoplasmic sperm injection (ICSI) may be the preferable method to treat partial globozoospermia,but whether there exist some correlations between ICSI fertilization rate and the proportion of round-headed sperm or morphologically normal sperm remains open.This study was to explore the correlation between ICSI fertilization rate and the sperm morphology in patients with partial globozoospermia.Methods:Thirty-four patients diagnosed with partial globozoospermia accepted the following assisted fertilization treatments-2 cases accepted in-vitro fertilization (IvF) alone,26 cases accepted ICSI alone,and 6 accepted split IVF/ICSI.Detailed morphological characteristics were described using Diff-Quik rapid staining.Sixty cases accepting IVF or ICSI treatment in our reproductive center were considered as the control group after being matched by relevant criteria.Fertilization rate,embryo quality,embryo implantation rate and clinical pregnancy rate were calculated.Results:Besides very high proportion of round-headed sperm,partial globozoospermia also showed very high proportion of small-acrosomal sperm and very low proportion of morphologically normal sperm.Fertilization rate of IVF (IVF alone plus split IVF) was very low in partial globozoospermia (25.4% ± 17.4%),but ICSI (ICSI alone plus split ICSI) achieved satisfying fertilization rate compared with the control group (66.2% ± 22.5% vs.68.8% ± 29.4%,P 〉 0.05).In patients with partial globozoospermia,there were no correlations between ICSI fertilization rate and the proportion of round-headed sperm,small-acrosomal sperm,or morphologically normal sperm.Conclusions:There was high proportion of small-acrosomal sperm in partial globozoospermia.For patients with partial globozoospermia,ICSI is more preferable than IVF.ICSI fertilization rate does not depend on the proportion of round-headed sperm,small-acrosomal sperm,or morphologically normal sperm. 展开更多
关键词 fertilization rate GLOBOZOOSPERMIA Intracytoplasmic Sperm Injection In-vitro fertilization Sperm Acrosome
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Grain Crop Fertilization Status and Factors Influencing Farmers' Decision Making on Fertilizer Use: China Case Study 被引量:5
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作者 闫湘 金继运 梁鸣早 《Agricultural Science & Technology》 CAS 2016年第10期2394-2398,2440,共6页
[Objective] China is the world's largest fertilizer consumer. Fertilizer plays an important role in maintaining China's food security. Along with population and economic growth, overuse of fertilizers has caused ser... [Objective] China is the world's largest fertilizer consumer. Fertilizer plays an important role in maintaining China's food security. Along with population and economic growth, overuse of fertilizers has caused serious environmental problems, such as soil acidification, decline in soil organic carbon, and agricultural non-point source pollution. This study aimed to analyze the factors influencing farmers" decision making on fertilizer use, and provide policy recommendations on ways to affect fertilization. [Method] An econometric model reflecting fertilization of rural households was estimated from a survey distributed to 1 043 households randomly selected from 19 provinces in China. [Result] Results of the study showed that education years of fertilizer decision maker, fertilizer quality, organic fertilizer application, fertilizer price, and agricultural product price had significant effects on the fertilizer application rate at 1% level. Soil nutrient affected the fertilizer application rate at 10% level. [Conclusion] Policies aimed at improving the reasonable use of fertilizer should focus on the regulation of chemical fertilizer price, foundation of the organic-inorganic fertilizer system, soil testing, formulated fertilization, and agricultural extension service. 展开更多
关键词 FARMERS Fertilizer application rate Influencing factors Double logarith- mic model
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Effects of Different Nitrogen Fertilizer Rates on Soluble Sugar,Starch and Root Tissue Structure of the Peach Trees
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作者 潘春香 肖艳辉 +1 位作者 新居直祐 中尾義則 《Agricultural Science & Technology》 CAS 2011年第12期1861-1863,共3页
[Objective] The research aimed to provide theoretical basis for the cultivation and production of peach.[Method] The three-year-old seedling peach tree was used as the materials,and NH4NO3 was used as the experimental... [Objective] The research aimed to provide theoretical basis for the cultivation and production of peach.[Method] The three-year-old seedling peach tree was used as the materials,and NH4NO3 was used as the experimental nitrogen fertilizer.Three nitrogen levels,0,3,6 g per pot respectively were set to study the effects of different nitrogen fertilizer on the contents of soluble sugar,starch and internal structure of the root of the peaches.[Result] The contents of soluble sugar of roots and leaves increased with the increase of nitrogen fertilizer level,and the level of 6 g per pot was the highest,which showed extreme differences between the level of 3 g per pot and the control.However,starch contents showed opposite results,which decreased as the level of nitrogen fertilizer increased.Compared with the 3 g per pot level of nitrogen fertilizer and the control,the internal structure of root applied with nitrogen fertilizer of 6 g per pot level had larger fibrovascularcylinder,advanced vascular bundle,small-spaced thin-walled cells,smooth and full cells with smooth cell wall.[Conclusion]Appropriate nitrogen levels can accelerate the accumulation of soluble sugar and the growth of root tissue structure. 展开更多
关键词 PEACH Nitrogen fertilizer rate Soluble sugar STARCH Root tissue structure
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Ensuring Long-Term Human Resources in the 21st Century With Adherence to Human Rights Standards
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作者 Gábor Kertész 《Economics World》 2025年第2期87-94,共8页
The longstanding debate persists:is the economy for the people,or are people for the economy?Technological advancements have increasingly reduced the need for physical human labor in economic activities.However,the de... The longstanding debate persists:is the economy for the people,or are people for the economy?Technological advancements have increasingly reduced the need for physical human labor in economic activities.However,the demand for human resources is expected to persist at some level.Historically,the necessary human resources for national economies have been sustained through birth rates or immigration.This study explores whether maintaining a stable fertility rate of 2.1 in modern EU member states can be achieved in the long term while adhering to constitutional and human rights standards. 展开更多
关键词 human resources fertility rate state-founded child
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Impact of Blood Clot in Oocyte-Corona-Cumulus Complex during in vitro Fertilization and Embryo Transfer
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作者 Yu-ling HUANG Xiao-ling LONG +2 位作者 Yong FAN Wen-hong ZHANG Hong-zi DU 《Journal of Reproduction and Contraception》 CAS 2012年第1期57-63,共7页
Objective To study the impact of blood clots in the oocyte-corona-cumulus complexes (OCCC) during in vitro fertilization and embryo transfer (IVF-ET).Methods The OCCCs were harvested from the patients undergoing l... Objective To study the impact of blood clots in the oocyte-corona-cumulus complexes (OCCC) during in vitro fertilization and embryo transfer (IVF-ET).Methods The OCCCs were harvested from the patients undergoing long protocol ovarian hyperstimulation. The OCCCs with blood clots removed or not, were randomly grouped into A or B. The OCCCs without blood clots were group C (the control).Results The patient's age, infertility duration, the average GN consumption, the average days of superovulation and an average number of harvested oocytes showed no significant difference in the 3 groups. The fertilization rate and 2PN rate in group A were the highest, which were 85.4% and 71.1%, respectively, followed by group C, which were 77.5% and 64.9%, respectively. The lowest fertilization rate and 2PN rate were in group B, 75.8% and 62.2%, respectively. Those in group A were significantly higher than those in groups B and C (P〈0.01), while there was no significant difference between group B and group C. The implantation rates and pregnancy rates showed no significant difference in the 3 groups after transplantation, even if group A got the highest rate among the 3 groups. Conclusion Removing the blood clots in OCCC can improve the outcome of IVF-ET without increasing the cost and complexity of the operation. 展开更多
关键词 in vitro fertilization and embryo transfer (IVF-ET) blood clot fertilization rate PREGNANCY
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Chemical fertilizer rate, use efficiency and reduction of cereal crops in China, 1998–2018 被引量:9
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作者 XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2022年第1期65-78,共14页
This paper studied the fertilizer rate(FR), fertilizer use efficiency(FUE) and fertilizer overuse rate(FOR) of rice, corn and wheat in China from 1998 to 2018 and briefly analysed the reasons why farmers were willing ... This paper studied the fertilizer rate(FR), fertilizer use efficiency(FUE) and fertilizer overuse rate(FOR) of rice, corn and wheat in China from 1998 to 2018 and briefly analysed the reasons why farmers were willing to apply more fertilizers.(1) The FR of grain in China reached 373.7 kg/ha in 2018, an increase of 26.8% compared to that in 1998. In 2018, the FR for corn was the highest, at 411.2 kg/ha, compared to the values of 338.3 kg/ha for rice and 371.7 kg/ha for wheat.(2) In recent years, the FUE of grain in China has obviously improved, with values of 32.9% in 1998, 36.7% in 2008, and 39.3% in 2018. In 2018, the FUE for rice was the highest(41.2%), followed by that for corn(39.9%), and the FUE for wheat was the lowest(36.0%).(3) By 2018, fertilizer was overused in all zones of rice, corn and wheat. In 2018, the average FOR for wheat reached 69.0%, which was 35.9% higher than that for corn and 42.8% higher than that for rice.(4) The lower price of chemical fertilizers was the main reason leading to overapplication.(5) Establishing market mechanisms and adjusting regional planting structures can be effective in reducing the application of chemical fertilizers. 展开更多
关键词 fertilizer rate(FR) fertilizer use efficiency(FUE) fertilizer overuse rate(FOR) China 1998–2018 three main grain crops
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Response of Tomato on Calcareous Soils to Different Seedbed Phosphorus Application Rates 被引量:8
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作者 ZHANG Xiao-Sheng LIAO Hong +3 位作者 CHEN Qing P. CHRISTIE LI Xiao-Lin ZHANG Fu-Suo 《Pedosphere》 SCIE CAS CSCD 2007年第1期70-76,共7页
Field experiments were conducted with five rates (0, 75, 150, 225, and 450 kg P205 ha^-1) of seedbed P fertilizer application to investigate the yield of tomato in response to fertilizer P rate on calcareous soils w... Field experiments were conducted with five rates (0, 75, 150, 225, and 450 kg P205 ha^-1) of seedbed P fertilizer application to investigate the yield of tomato in response to fertilizer P rate on calcareous soils with widely different levels of Olsen P (13-142 mg kg^-1) at 15 sites in some suburban counties of Beijing in 1999. Under the condition of no P fertilizer application, tomato yield generally increased with an increase in soil test P levels, and the agronomic level for soil testing P measured with Olsen method was 50 or 82 mg kg^-1 soil to achieve 85% or 95% of maximum tomato yield, respectively. With regard to marketable yield, in the fields where Olsen-P levels were 〈 50 mg kg^-1, noticeable responses to applied P were observed. On the basis of a linear plateau regression, the optimum seedbed P application rate in the P-insufflcient fields was 125 kg P205 ha^-1 or about 1.5-2 times the P removal from harvested tomato plants. In contrast, in fields with moderate (50 〈 Olsen P 〈 90 mg kg^-1) or high (Olsen P 〉 90 mg kg^-1) available P, there was no marked effect on tomato fruit yield. Field survey data indicated that in most fields with conventional P management, a P surplus typically occurred. Thus, once the soil test P level reached the optimum for crop yield, it was recommended that P fertilizer application be restricted or eliminated to minimize negative environmental effects. 展开更多
关键词 calcareous soils fertilizer P rate soil test P tomato yield vegetable fields
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Abundance and Community Composition of Ammonia-Oxidizers in Paddy Soil at Different Nitrogen Fertilizer Rates 被引量:6
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作者 SONG Ya-na LIN Zhi-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期870-880,共11页
Ammonia oxidation, the first and rate-limiting step of nitrification, is carried out by both ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). However, the relative importance of AOB and AOA to... Ammonia oxidation, the first and rate-limiting step of nitrification, is carried out by both ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). However, the relative importance of AOB and AOA to nitrification in terrestrial ecosystems is not well understood. The aim of this study was to investigate the effect of the nitrogen input amount on abundance and community composition of AOB and AOA in red paddy soil. Soil samples of 10-20 cm (root layer soil) and 0-5 cm (surface soil) depths were taken from a red paddy. Rice in the paddy was fertilized with different rates of N as urea of N1 (75 kg N ha" yr-1), N2 (150 kg N ha~ yrl), N3 (225 kg N ha1 yrl) and CK (without fertilizers) in 2009, 2010 and 2011. Abundance and community composition of ammonia oxidizers was analyzed by real-time PCR and denaturing gradient gel electrophoresis (DGGE) based on amoA (the unit A of ammonia monooxygenase) gene. Archaeal amoA copies in N3 and N2 were significantly (P〈0.05) higher than those in CK and N1 in root layer soil or in surface soil under tillering and heading stages of rice, while the enhancement in bacterial amoA gene copies with increasing of N fertilizer rates only took on in root layer soil. N availability and soil NO3--N content increased but soil NH4+-N content didn't change with increasing of N fertilizer rates. Otherwise, the copy numbers of archaeal amoA gene were higher (P〈0.05) than those of bacterial amoA gene in root lary soil or in surface soil. Redundancy discriminate analysis based on DGGE bands showed that there were no obvious differs in composition of AOA or AOB communities in the field among different N fertilizer rates. Results of this study suggested that the abundance of ammonia-oxidizers had active response to N fertilizer rates and the response of AOA was more obvious than that of AOB. Similarity in the community composition of AOA or AOB among different N fertilizer rates indicate that the community composition of ammonia-oxidizers was relatively stable in the paddy soil at least in short term for three years. 展开更多
关键词 ammonia-oxidizing bacteria ammonia-oxidizing archaea nitrogen fertilizer rates paddy soil
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Net energy yield and carbon footprint of summer corn under different N fertilizer rates in the North China Plain 被引量:4
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作者 WANG Zhan-biao WEN Xin-ya +2 位作者 ZHANG Hai-lin LU Xiao-hong CHEN Fu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第8期1534-1541,共8页
Excessive use of N fertilizer in intensive agriculture can increase crop yield and at the same time cause high carbon(C) emissions.This study was conducted to determine optimized N fertilizer application for high gr... Excessive use of N fertilizer in intensive agriculture can increase crop yield and at the same time cause high carbon(C) emissions.This study was conducted to determine optimized N fertilizer application for high grain yield and lower C emissions in summer corn(Zea mays L.).A field experiment, including 0(N0), 75(N75), 150(N150), 225(N225), and 300(N300) kg N ha–1 treatments, was carried out during 2010–2012 in the North China Plain(NCP).The results showed that grain yield, input energy, greenhouse gas(GHG) emissions, and carbon footprint(CF) were all increased with the increase of N rate, except net energy yield(NEY).The treatment of N225 had the highest grain yield(10 364.7 kg ha–1) and NEY(6.8%), but the CF(0.25) was lower than that of N300, which indicates that a rate of 225 kg N ha–1 can be optimal for summer corn in NCP.Comparing GHG emision compontents, N fertilizer(0–51.1%) was the highest and followed by electricity for irrigation(19.73–49.35%).We conclude that optimazing N fertilizer application rate and reducing electricity for irrigation are the two key measures to increase crop yield, improve energy efficiency and decrease GHG emissions in corn production. 展开更多
关键词 MAIZE nitrogen fertilizer rate grain yield net energy ratio greenhouse gas emissions
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Magnetic-activated cell sorting of nonapoptotic spermatozoa with a high DNA fragmentation index improves the live birth rate and decreases transfer cycles of IVF/ICSI 被引量:4
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作者 Jie Mei Lin-Jun Chen +5 位作者 Xin-Xin Zhu Wen Yu Qing-Qiang Gao Hai-Xiang Sun Li-Jun Ding Jun-Xia Wang 《Asian Journal of Andrology》 SCIE CAS CSCD 2022年第4期367-372,共6页
The present study aimed to evaluate the clinical outcomes of magnetic-activated cell sorting(MACS)in sperm preparation for male subjects with a sperm DNA fragmentation index(DFI)≥30%.A total of 86 patients who had un... The present study aimed to evaluate the clinical outcomes of magnetic-activated cell sorting(MACS)in sperm preparation for male subjects with a sperm DNA fragmentation index(DFI)≥30%.A total of 86 patients who had undergone their first long-term long protocol were selected.The protocol involved in vitro fertilization(IVF)and intracytoplasmic sperm injection(ICSI)cycles,and the patients were divided into the MACS or control groups.The MACS group included sperm samples analyzed with MACS that were combined with density gradient centrifugation(DGC)and the swim-up(SU)technique(n=39),and the control group included sperm samples prepared using standard techniques(DGC and SU;n=41).No differences were noted with regard to basic clinical characteristics,number of oocytes retrieved,normal fertilization rate,cleavage rate,or transplantable embryo rate between the two groups in IVF/ICSI.In addition,the clinical pregnancy and implantation rates of the first embryo transfer cycles indicated no significant differences between the two groups.However,there was a tendency to improve the live birth rate(LBR)of the first embryo transfer cycle(63.2%vs 53.9%)and the cumulative LBR(79.5%vs 70.7%)in the MACS group compared with the control group.Moreover,the number of transferred embryos(mean±standard deviation[s.d.]:1.7±0.7 vs 2.3±1.6)and the transfer number of each retrieved cycle(mean±s.d.:1.2±0.5 vs 1.6±0.8)were significantly lower in the MACS group than those in the control group.Thus,the selection of nonapoptotic spermatozoa by MACS for higher sperm DFI could improve assisted reproductive clinical outcomes. 展开更多
关键词 cumulative live birth rate fertility rate intracytoplasmic sperm injection sperm DNA fragmentation index sperm DNA integrity
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Use of Several Plant Materials and Chemicals to inhibit Soil Urease Activity and Increase Nitrogen Recovery Rate of Urea by Plant 被引量:6
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作者 XU WEIHONG, WANG ZHENGYIN, JIA ZHONGYUAN, HUANG YUN, YUAN LUJIANG and WANG JUANMEICollege of Resources and Environmental Science, Southwest Agricultural University, Chongqing 400716 (China) 《Pedosphere》 SCIE CAS CSCD 2002年第3期275-282,共8页
Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Li... Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Linn.) O. Ktze. f., P_4), oleander (Nerium indicum Mill,P_5), rape (Brassica campestris L., P_g), Chinese tallow tree (Sapium sebiferum L., P_7), tung(Vernicia fordii (Hemsl.), P_8), and croton (Croton tiglium L., P_9), 7 chemicals, boric acid (C_1),borax (C_2), oxalic acid (C_3), sodium oxalite (C_4), sodium dihydrogen phosphate (C_6), sodiumsilicate (C_7) and sodium citrate (C_8), and a natural organic substance, humic acid (C_5), onurease activity of a neutral purple soil and recovery of urea nitrogen by maize were studied throughincubation and pot experiments. Hydroquinone (HQ) was applied as the reference inhibitor. Afterincubation at 37℃ for 24 h, 7 inhibitors with higher ability to inhibit urease activity wereselected and then incubated for 14 days at 25℃. Results of the incubation experiments showed thatsoil urease activity was greatly inhibited by them, and the inhibition effect followed an order ofP_2>P_4>C_3>C_2>P_3>C_1>HQ>P_1. The 7 selected materials reduced the accumulative amounts of Nreleased from urea and the maximum urease activity by 11.7%~28.4% and 26.7%~39.7%, respectively,and postponed the N release peak by 2~4 days in the incubation period of 14 days under constanttemperature, as compared to the control (no inhibitor). In the pot experiment with the 7 materialsat two levels of addition, low (L) and high (H), the C_1 (H), C_3 (H), C_1 (L), P_4 (L) and C_2 (L)treatments could significantly increase the dry weights of the aboveground parts and the totalbiomass of the maize plants and the apparent recovery rate of urea-N was increased by 6.3%~32.4% ascompared to the control (no hibitor). 展开更多
关键词 CHEMICALS plant materials recovery rate of fertilizer nitrogen ureaseactivity
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Effects of supplying silicon nutrient on utilization rate of nitrogen and phosphorus nutrients by rice and its soil ecological mechanism in a hybrid rice double-cropping system 被引量:7
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作者 Min LIAO Zhi-ping FANG +6 位作者 Yu-qi LIANG Xiao-hui HUANG Xu YANG Shu-sen CHEN Xiao-mei XIE Chang-xu XU Jia-wen GUO 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2020年第6期474-484,共11页
This study was conducted to reveal the effects of silicon(Si) application on nutrient utilization efficiency by rice and on soil nutrient availability and soil microorganisms in a hybrid rice double-cropping planting ... This study was conducted to reveal the effects of silicon(Si) application on nutrient utilization efficiency by rice and on soil nutrient availability and soil microorganisms in a hybrid rice double-cropping planting system. A series of field experiments were conducted during 2017 and 2018. The results showed that Si nutrient supply improved grain yield and the utilization rates of nitrogen(N) and phosphorus(P) to an appropriate level for both early and late plantings, reaching a maximum at 23.4 kg/ha Si. The same trends were found for the ratios of available N(AN) to total N(TN) and available P(AP) to total P(TP), the soil microbial biomass carbon(MBC), microbial biomass nitrogen(MBN), microbial biomass phosphorus(MBP), and the ratios of MBN to TN and MBP to TP, at different levels of Si. Statistical analysis further revealed that Si application enhanced rice growth and increased the utilization rate of fertilizer due to an ecological mechanism, i.e., Si supply significantly increased the total amount of soil microorganisms in paddy soil compared to the control. This promoted the mineralization of soil nutrients and improved the availability and reserves of easily mineralized organic nutrients. 展开更多
关键词 Silicon nutrient Utilization rate of fertilizer Ecological mechanism Rice double-cropping system
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The Difficulties in Raising Fertility Rates-The Deficiencies and Improvements of the Maternity Protection System for Women of Childbearing Age 被引量:1
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作者 Jia Yujiao Huang Deyuan 《Contemporary Social Sciences》 2020年第3期143-154,共12页
Fertility policies consist of not only the legal definition of"procreation",but also the"maternity"protection system,the complete set of selfconsistent social relations and policy systems formed ar... Fertility policies consist of not only the legal definition of"procreation",but also the"maternity"protection system,the complete set of selfconsistent social relations and policy systems formed around"fertility".Gender,labor and intergenerational relations are the cornerstones of a fertility policy system.In this framework,we focus on women of childbearing age as the main actors of reproductive behaviors,to research how drastic social changes have altered women,the above-mentioned relations,and policy support and analyze the structural factors that restrict women’s reproductive intentions.The traditional male breadwinner model,which can no longer prevail and the relatively slow development of maternity protection policies and service systems leave women of childbearing age in a dilemma between working hours and birth timing.Therefore,maternity protection policies should focus on improved decommodification of maternity insurance and the construction of women and children’s social welfare systems including childcare social service systems. 展开更多
关键词 reproductive behaviors social support for women fertility policy fertility rate
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Growth Parameters of DK8031 Maize Variety as Affected by Varying Irrigation and Nitrogen Fertilizer Rates in Embu County, Kenya
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作者 Charles Nyambane Onyari Antony Mwangi Kibe Samuel Mwonga 《Journal of Environmental Science and Engineering(A)》 2015年第8期432-444,共13页
Determination of crop growth parameters of maize helps assess the performance of the crop for food security. A study was conducted in two seasons covering 2012 and 2013 to establish optimal irrigation and nitrogen fer... Determination of crop growth parameters of maize helps assess the performance of the crop for food security. A study was conducted in two seasons covering 2012 and 2013 to establish optimal irrigation and nitrogen fertilizer rates for drought tolerant hybrid maize (Zea mays L.), DK8031 variety, in sandy loam soils using furrow irrigation. Four additive irrigation levels (119.05 mm, 238.10 mm, 357.15 mm and 476.2 mm) were allocated the main plots while five nitrogen fertilizer rates (0 kg/ha, 60, 75 kg/ha, 90 kg/ha and 100 kg/ha) were allocated the sub-plots. Both irrigation and nitrogen fertilizer treatments significantly enhanced crop growth parameters under consideration. Stand count per treatment plot, plant height and number of leaves per ranged from 45-59 plants/plot, 215-238 cm and 14-16 leaves respectively. It was concluded that use of supplementary irrigation and phased nitrogen fertilizer rates for maize growing in areas such as Embu can greatly promote crop growth. 展开更多
关键词 MAIZE IRRIGATION nitrogen fertilizer rates plant height leaves per plant.
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Human circBOULE RNAs as potential biomarkers for sperm quality and male infertility 被引量:1
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作者 Liping Cheng He Jin +3 位作者 Tianheng Xiao Xiaoyu Yang Tingting Zhao Eugene Yujun Xu 《Journal of Biomedical Research》 CAS CSCD 2024年第5期473-484,I0003-I0008,共18页
Reliable molecular biomarkers to predict fertility remain scarce.The current study investigated the potential of testis-specific circBOULE RNAs as biomarkers for male infertility and sperm quality.Using reverse transc... Reliable molecular biomarkers to predict fertility remain scarce.The current study investigated the potential of testis-specific circBOULE RNAs as biomarkers for male infertility and sperm quality.Using reverse transcription-PCR and real-time reverse transcription-PCR assays,we identified seven circular RNAs from the human BOULE gene in human sperm.We observed that the expression level of circEx3-6 was significantly reduced in asthenozoospermia,while the expression levels of both circEx2-6 and circEx2-7 were decreased in terato-zoospermia,compared with the controls.Furthermore,we demonstrated that the expression level of circEx2-6 was negatively correlated with the sperm DNA fragmentation index,and the expression level of circEx2-7 was correlated with both fertilization and cleavage rates in those treated with the assisted reproductive technologies.Further functional analyses in a transgenic fly model supported the roles of circBOULE RNAs in sperm development and human male fertility.Collectively,our findings support that sperm circBOULE RNAs may serve as diagnostic biomarkers for assessing sperm motility and DNA quality.Therefore,clinical application and significance of sperm circBOULE RNAs in the assisted reproductive technologies warrant further investigation. 展开更多
关键词 human circBOULE RNAs sperm DNA fragmentation index fertilization rate cleavage rate semen parameters assisted reproductive technology
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Evaluation of Variable Rate Technology for Fertilizer Application in Permanent Pastures
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作者 J. M. Serrano J. M. Peca Shahidian 《Journal of Agricultural Science and Technology(A)》 2011年第4X期489-499,共11页
This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a signifi... This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a significant and systematic difference between the application rates of the two discs (about 20%). This difference had to be corrected by the manufacturer that carried out the necessary changes to the electric actuators. The fertilizer spreader had good distribution homogeneity, considering different working velocities and different positions in the parcel. The pattern distribution curve for 18% super phosphate fertilizer led to an effective working width of 28 meters, with a coefficient of variation of 15%. The longitudinal test, under experimental working conditions led to a machine delay time of 6-7 seconds. The results show an actual fertilization application density between 74%-90% of that determined for each location. These results confirm that the spreader can be used to spread fertilizer differentially in the field. 展开更多
关键词 Calibration centrifugal fertilizer spreader evaluation precision agriculture variable rate technology.
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Sperm acrosin activity may be a useful factor in choosing between ICSI and IVF for infertile male patients
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作者 Ye-Na Hu Liang Hu +5 位作者 Xin-Yu Yin Huan Zhang Yang-Qin Peng Gang Liu Ge Lin Wei-Na Li 《Asian Journal of Andrology》 SCIE CAS CSCD 2024年第1期85-90,共6页
The clinical applications of acrosin activity are limited.We analyzed 61578 male partners in infertile couples who visited the outpatient department of the Reproductive and Genetic Hospital of CITIC-Xiangya(Changsha,C... The clinical applications of acrosin activity are limited.We analyzed 61578 male partners in infertile couples who visited the outpatient department of the Reproductive and Genetic Hospital of CITIC-Xiangya(Changsha,China)between August 2014 and December 2019 to determine the reference ranges and thresholds for acrosin activity in infertile Chinese men;to determine whether correlations exist between acrosin activity and age,sperm concentration,sperm morphology,or sperm motility;and to evaluate whether acrosin activity could serve as an effective prognostic indicator for choosing between in vitro fertilization(IvF)and intracytoplasmic sperm injection(icsl)in the clinic.The cut-off value for the normal reference range of acrosin activity for male partners in infertile couples was 24.78μlU per 106 sperm.There was no significant association between acrosin activity and age,sperm concentration,semen volume,total sperm count,progressive motility,or total motile spermatozoa.A weak positive correlation was found between acrosin activity and normal sperm morphology.There was a statistically significant difference in abnormal acrosome morphology between the group with high acrosin activity(>24.78μlU per 106 sperm)and the group with low acrosin activity(<24.78μlU per 106 sperm).The group with a low IVF fertilization rate had a high index of abnormal acrosomal morphology at 21.2%,while the group with a high IVF fertilization rate had a low index of 0.2%.At an acrosin activity of<24.78μlU per 10 sperm,in one cycle of the same patient,the fertilization rate,normal fertilization rate,and good-quality embryo rate for Icsl were significantly higher than those for IVF.Therefore,the most promising application of acrosin activity could be in the selection of IcsI over IVF for infertile male patients with complete fertilization failure or a low fertilization rate. 展开更多
关键词 acrosin activity fertilization rate ICSI IVF semen parameters
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