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Readmission rate and early complications in patients undergoing total knee arthroplasty:A retrospective study
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作者 Tushar Jethi Deepak Jain +1 位作者 Rajnish Garg Harpal Singh Selhi 《World Journal of Orthopedics》 2024年第8期713-721,共9页
BACKGROUND Total knee arthroplasty(TKA)can improve pain,quality of life,and functional outcomes.Although uncommon,postoperative complications are extremely consequential and thus must be carefully tracked and communic... BACKGROUND Total knee arthroplasty(TKA)can improve pain,quality of life,and functional outcomes.Although uncommon,postoperative complications are extremely consequential and thus must be carefully tracked and communicated to patients to assist their decision-making before surgery.Identification of the risk factors for complications and readmissions after TKA,taking into account common causes,temporal trends,and risk variables that can be changed or left unmodified,will benefit this process.AIM To assess readmission rates,early complications and their causes after TKA at 30 days and 90 days post-surgery.METHODS This was a prospective and retrospective study of 633 patients who underwent TKA at our hospital between January 1,2017,and February 28,2022.Of the 633 patients,28 were not contactable,leaving 609 who met the inclusion criteria.Both inpatient and outpatient hospital records were retrieved,and observations were noted in the data collection forms.RESULTS Following TKA,the 30-day and 90-day readmission rates were determined to be 1.1%(n=7)and 1.8%(n=11),respectively.The unplanned visit rate at 30 days following TKA was 2.6%(n=16)and at 90 days was 4.6%(n=28).At 90 days,the unplanned readmission rate was 1.4%(n=9).Reasons for readmissions included medical(27.2%,n=3)and surgical(72.7%,n=8).Unplanned readmissions and visits within 90 days of follow-up did not substantially differ by age group(P=0.922),body mass index(BMI)(P=0.633),unilateral vs bilateral TKA(P=0.696),or patient comorbidity status(30-day P=0.171 and 90-day P=0.813).Reoperation rates after TKA were 0.66%(n=4)at 30 days and 1.15%(n=8)at 90 days.The average length of stay was 6.53 days.CONCLUSION In this study,there was a low readmission rate following TKA.There was no significant correlation between readmission rate and patient factors such as age,BMI,and co-morbidity status. 展开更多
关键词 total knee arthroplasty Length of stay READMISSION rates CAUSES Risk factors PROSPECTIVE RETROSPECTIVE FOLLOW-UP REOPERATION
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Human circBOULE RNAs as potential biomarkers for sperm quality and male infertility
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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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Effects of Different Decolorants on Retention Rate of Total Triterpenes in Fruit and Rattan Stems of Schisandra chinensis(Turcz.) Baill
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作者 刘俊霞 金银萍 +2 位作者 窦凤鸣 王玉帅 王英平 《Agricultural Science & Technology》 CAS 2015年第12期2600-2603,共4页
This study was to investigate the decoloration effects of activated clay, activated carbon, diatomite, Ca group bentonite, kaolin, activated aluminum oxide, magnesium oxide and attapulgite. Ultraviolet-visible spectro... This study was to investigate the decoloration effects of activated clay, activated carbon, diatomite, Ca group bentonite, kaolin, activated aluminum oxide, magnesium oxide and attapulgite. Ultraviolet-visible spectroscopywas adopted to de- tect the absorbanees of the extracts of Schisandra chinensis fruit and rattan stems, the contents of total triterpenoids in S. chinensis fruit and rattan stems were deter- mined, and the decoloration rate and the retention rate of total triterpenoids of S. chi- nensis fruit and rattan stems were calculated. The results indicated that, attapulgite exhibited the best decoloration effect on the extract of S. chinensis fruit, with a de- coloration rate up to 60.47%, activated carbon exhibited a better decoloration effect on the extract of S. chinensis rattan stems, with a decoloration rate up to 69.24%, and they had relatively higher retention rates of total triterpenoids. In the eight de- colorants, attapulgite showed the best decoloration effect on the extract of S. chi- nensis fruit, and activated carbon exhibited the best decoloration effect on the ex- tract of S. chinensisrattan stems. 展开更多
关键词 Schisandra chinensis (Turcz.) Baill total triterpenoids DECELERATION At- tapulgite Activated carbon Retention rate
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Estimating time-based instantaneous total mortality rate based on the age-structured abundance index 被引量:1
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作者 王迎宾 JIAO Yan 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期559-576,共18页
The instantaneous total mortality rate(Z) of a fish population is one of the important parameters in fisheries stock assessment. The estimation of Z is crucial to fish population dynamics analysis,abundance and catch ... The instantaneous total mortality rate(Z) of a fish population is one of the important parameters in fisheries stock assessment. The estimation of Z is crucial to fish population dynamics analysis,abundance and catch forecast,and fisheries management. A catch curve-based method for estimating time-based Z and its change trend from catch per unit effort(CPUE) data of multiple cohorts is developed. Unlike the traditional catch-curve method,the method developed here does not need the assumption of constant Z throughout the time,but the Z values in n continuous years are assumed constant,and then the Z values in different n continuous years are estimated using the age-based CPUE data within these years. The results of the simulation analyses show that the trends of the estimated time-based Z are consistent with the trends of the true Z,and the estimated rates of change from this approach are close to the true change rates(the relative differences between the change rates of the estimated Z and the true Z are smaller than 10%). Variations of both Z and recruitment can affect the estimates of Z value and the trend of Z. The most appropriate value of n can be different given the effects of different factors. Therefore,the appropriate value of n for different fisheries should be determined through a simulation analysis as we demonstrated in this study. Further analyses suggested that selectivity and age estimation are also two factors that can affect the estimated Z values if there is error in either of them,but the estimated change rates of Z are still close to the true change rates. We also applied this approach to the Atlantic cod(G adus morhua) fishery of eastern Newfoundland and Labrador from 1983 to 1997,and obtained reasonable estimates of time-based Z. 展开更多
关键词 instantaneous total mortality rate (Z) catch per unit effort (CPUE) time-based change trend SIMULATION SELECTIVITY incorrect age estimation
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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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Influence of the total gas flow rate on high rate growth microcrystalline silicon films and solar cells
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作者 韩晓艳 侯国付 +8 位作者 张晓丹 魏长春 李贵君 张德坤 陈新亮 孙健 张建军 赵颖 耿新华 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3563-3567,共5页
This paper reports that high-rate-deposition of microcrystalline silicon solar cells was performed by very-highfrequency plasma-enhanced chemical vapor deposition. These solar cells, whose intrinsic μc-Si:H layers w... This paper reports that high-rate-deposition of microcrystalline silicon solar cells was performed by very-highfrequency plasma-enhanced chemical vapor deposition. These solar cells, whose intrinsic μc-Si:H layers were prepared by using a different total gas flow rate (Ftotal), behave much differently in performance, although their intrinsic layers have similar crystalline volume fraction, opto-electronic properties and a deposition rate of - 1.0 nm/s. The influence of Ftotal on the micro-structural properties was analyzed by Raman and Fourier transformed infrared measurements. The results showed that the vertical uniformity and the compact degree of μc-Si:H thin films were improved with increasing Ftotal. The variation of the microstructure was regarded as the main reason for the difference of the J V parameters. Combined with optical emission spectroscopy, we found that the gas temperature plays an important role in determining the microstructure of thin films. With Ftotal of 300 sccm, a conversion efficiency of 8.11% has been obtained for the intrinsic layer deposited at 8.5 A/s (1 A=0.1 nm). 展开更多
关键词 microcrystalline silicon high rate solar cell total gas flow rate
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Optimal use of fielder XT guidewire enhances the success rate of chronic total occlusion percutaneous coronary intervention
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作者 Qian-Cheng Wang Hai-Ruo Lin +8 位作者 Yuan Han Hai Dong Kai Xu Shao-Yi Guan Zhen-Huan Chen Hui-Xin Hao Jian-Ping Bin Yu-Lin Liao Quan-Min Jing 《World Journal of Clinical Cases》 SCIE 2019年第8期928-939,共12页
BACKGROUND Chronic total occlusion(CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-... BACKGROUND Chronic total occlusion(CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-term survival.Although the success rate of CTO percutaneous coronary intervention(CTO-PCI)has improved, CTO-PCI remains technically challenging. The Fielder XT guidewire was designed for CTO lesions. To validate whether the use of the guidewire increases the success rate, we compared the results of CTO-PCI with or without the guidewire. We hypothesized that the use of Fielder XT guidewire can increase the success rate of CTO-PCI.AIM To investigate whether the use of Fielder XT guidewire increases the final procedural success of CTO-PCI via the anterograde approach.METHODS Between January 2013 and December 2015, a retrospective study was conducted on 1230 consecutive patients with CTO who received PCI via the anterograde approach at the General Hospital of Northern Theater Command. The patients were divided into an XT Group(n = 686) and a no-XT Group(n = 544) depending on whether Fielder XT guidewire was used. Both groups were compared for clinical parameters, lesion-related characteristics, procedural outcomes and inhospital complications. The data were statistically analyzed using Pearson's χ~2 test for categorical variables, and Students' t test was used to compare the quantitative data. Significant independent factors and a risk ratio with 95%confidence interval(CI) were assessed by multivariate logistic regression analysis.RESULTS In total, 1230 patients were recruited; 75.4% of the patients were male, and 55.8%of the patients were in the XT group. The overall success rate was 83.9%, with87.8% in the XT group. Based on multivariate logistic regression analysis, factors positively associated with procedural success were the use of Fielder XT guidewire(P = 0.005, 95%CI: 1.172-2.380) and systolic blood pressure(P = 0.011,95%CI: 1.003-1.022), while factors negatively associated with procedural success were blunt stump(P = 0.013, 95%CI: 1.341-11.862), male sex(P = 0.016, 95%CI:0.363-0.902), New York Heart Association(NYHA) class(P = 0.035, 95%CI: 0.553-0.979), contrast amount(P = 0.018, 95%CI: 0.983-0.998) and occlusion time(P =0.009, 95%CI: 0.994-0.999). No significant differences were found between the XT group and the no-XT group with respect to clinical parameters, lesion-related characteristics, coronary artery rupture [3(0.4%) vs 8(1.5%), P = 0.056], inhospital death [2(0.3%) vs 6(1.1%), P = 0.079] or in-hospital target lesion revascularization [3(0.4%) vs 7(1.3%), P < 0.099]. However, there were significant differences between the groups with respect to success rate [602(87.8%) vs 430(79.0%), P < 0.001], procedure time [(74 ± 23) vs(83 ± 21), P < 0.001], stent length[(32.0 ± 15.8) vs(37.3 ± 17.6), P < 0.001], contrast amount [(148 ± 46) vs(166 ± 43),P < 0.001], post-PCI myocardial infarction [43(6.3%) vs 59(10.8%), P = 0.004],major adverse cardiovascular event [44(6.4%) vs 57(10.7%), P = 0.007], side branch loss [31(4.5%) vs 44(8.1%), P = 0.009], contrast-induced nephropathy [29(4.2%) vs 40(7.4%), P = 0.018] and no reflow [8(1.2%) vs 14(2.9%), P = 0.034].CONCLUSION The use of Fielder XT guidewire shortens the Procedure and increases the success rate of CTO-PCI, and is also associated with reduced complication rates. 展开更多
关键词 Chronic total occlusion Percutaneous coronary intervention ANTEROGRADE WIRE ESCALATION Parallel WIRE technique Fielder XT GUIDEWIRE Success rate
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Commissioning and Optimization of a Total Skin Electron Therapy Technique Using a High Dose Rate Electron Facility
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作者 Y. A. M. Yousif Casper A. Willemse 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2015年第3期197-207,共11页
Total skin electron therapy (TSET) is used for the treatment of Mycosis Fungoides. Several tech-niques have been developed, in order to achieve homogeneous dose distribution over the complete body surface. To implemen... Total skin electron therapy (TSET) is used for the treatment of Mycosis Fungoides. Several tech-niques have been developed, in order to achieve homogeneous dose distribution over the complete body surface. To implement a TSET technique, one has to optimize a variety of parameters. Monte Carlo simulation of TSET can facilitate this optimization. The aim of this study was to commission and optimize a TSET technique using the 4 and 6 MeV electron and the high dose rate facility on the Elekta Precise accelerator. The EGS4nrc/BEAMnrc Monte Carlo code was used. The beam data were calculated and measured at two different scoring planes for a single beam. The Model was validated by comparing the simulation with measurements. Two different vertical angles were used to obtain a uniform dose. The angle was optimized for best dose uniformity. The Rando phantom is placed on a rotating platform and rotates 60 degrees apart to facilitate the six patient position orientations. The doses delivered in a phantom by complete treatment were measured with Kodak EDR2 films and TLDs. The dose distribution varied among various scanning directions by 2 - 3 mm and 3 - 4 mm for 4 and 6 MeV respectively. The composite percentage depth dose of all six dual fields for the 4 and 6 MeV yielded an R80 of ~4 mm and ~6 mm, respectively. Dose uniformity was ±6% for 4 MeV and ±5% for 6 MeV. The bremsstrahlung contamination was 0.9% - 1.3%. Good agreements were found with published literature and inline with international protocols. 展开更多
关键词 total SKIN ELECTRON THERAPY MYCOSIS Fungoides High DOSE rate ELECTRON Monte Carlo Simulation
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Frequency of Monthly Ejaculation at Sexual Intercourse, DNA Fragmentation Index and Fertilization Rate among Sperm Donors and Fertility-Challenged Men in Sub-Saharan Africa: Paper 2
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作者 Abayomi B. Ajayi Bamgboye M. Afolabi +6 位作者 Victor D. Ajayi Ifeoluwa O. Oyetunji Adedamilola Atiba Seun Saanu Ayodeji T. Adeoye Joy I. Ehichioya Ibukun I. Ayelehin 《Open Journal of Urology》 2020年第3期60-78,共19页
Introduction: Heterogenous sexual intercourse often produces a powerful orgasm that stimulates the pituitary function. Studies have suggested ejaculation frequency based on age. Materials and Methods: Semi-structured ... Introduction: Heterogenous sexual intercourse often produces a powerful orgasm that stimulates the pituitary function. Studies have suggested ejaculation frequency based on age. Materials and Methods: Semi-structured questionnaires were used to collect information from subjects. Semen samples were collected from sperm donors and sub-fertile men who presented for infertility challenges. Processing and analysis of semen samples were done according to World Health Organization (WHO) guidelines. Sperm deoxyribonucleic acid (DNA) fragmentation was evaluated using the Halosperm kit. Results: Among sperm donors, those aged χ2 = 0.09, P-value = 0.81, OR = 3.2, 95% CI: 0.23, 45.19) while among sub-fertile men those aged ≥40 years were approximately 2.3 times more likely to have very low frequency of MESI compared to aged χ2 = 2.11, P-value = 0.51, OR = 2.27, 95% CI: 0.74, 9.92). The frequency of all categories of MESI was highest among sub-fertile men aged χ2 = 0.03, P-value = 0.57, OR = 2.42, 95% CI: 0.41, 14.46). Sub-fertile men aged ≥40 with diastolic hypertension (≥90 mmHg) were approximately 6 times more likely to have a low (6 - 10) frequency of MESI compared to those aged χ2 = 1.97, P-value = 0.16, OR = 6.22, 95% CI: 0.69, 55.77). Overall mean fertilization rate was significantly higher (t-test = 2.44, P-value = 0.01) among sub-fertile men aged Conclusion: Cigarette smoking, more than alcohol consumption, appears to be a major factor that significantly affects the frequency of MESI among sub-fertile men in all age groups. Frequency of MESI negatively but insignificantly correlated with systolic blood pressure. 展开更多
关键词 MONTHLY EJACULATION at Sexual INTERCOURSE Systolic and Diastolic Blood Pressures DNA Fragmentation INDEX Fertilization rates Social Habits Sub-Fertile Males Sub-Sahara Black AFRICANS
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Non-regular Employment of Women,Fertility Rate,and Economic Growth
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作者 Kei Murata 《Economics World》 2018年第3期217-227,共11页
This study analyzes the interaction between non-regular employment of women and economic growth patterns by an overlapping-generations model.Declining Birthrate White Paper-Cabinet Office(2013)shows the ideal number o... This study analyzes the interaction between non-regular employment of women and economic growth patterns by an overlapping-generations model.Declining Birthrate White Paper-Cabinet Office(2013)shows the ideal number of children per household is 2.42 compared to the current number of 2.07,which is the lowest so far in Japan.The main reason households do not have the ideal number of children is“the costs burden of childcare and education”and the ratio amounts to 60.4%.In recent years in Japan,households in which both the husband and the wife work are increasing,whereas those in which only the husband works are decreasing.Additionally,although women have same educational background and abilities as men,most women become non-regular employees after marriage and childbirth,which reduces household income.In such a situation,raising the rate of pension insurance will be a big burden for the household and the declining birthrate may be caused by high levels of educational expenditure and pension insurance.The Japanese government has discussed raising the wages of non-regular employees.This paper finds that a rise in the wage rate of non-regular employment is needed under the public pension policy that raises the rate of pension insurance,and it must be at an adequate level.That is,there is a high risk that this policy will have a negative effect on Japan’s economic growth if an adequate level is not achieved. 展开更多
关键词 overlapping-generations EMPLOYMENT of WOMEN fertility rate public PENSION policy human CAPITAL economic growth
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Effects of Different Application Rates of Bioorganic Fertilizer on the Growth of Spinach in a Short Term
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作者 Yanxue DANG Shengqun JIAO +5 位作者 Hongjie TANG Qingfu DU Jihui LI Bushuai ZHONG Kaixuan ZHOU Peng WANG 《Agricultural Biotechnology》 CAS 2023年第3期125-127,共3页
[Objectives]This study was conducted to promote the rational use of bioorganic fertilizers.[Methods]Stanley bioorganic fertilizer was selected to investigate the laws and characteristics of the effects of bioorganic f... [Objectives]This study was conducted to promote the rational use of bioorganic fertilizers.[Methods]Stanley bioorganic fertilizer was selected to investigate the laws and characteristics of the effects of bioorganic fertilizer on spinach growth with different application rates in a short term and found out the precise application rate.[Results]As the application rate of bioorganic fertilizer increasing,the emergence rate of spinach decreased.The total weights and leaf areas of spinach plants treated with different application rates of bioorganic fertilizers were all higher than those of the control check(CK).The total weights and leaf areas of spinach plants applied with bioorganic fertilizer at different rates were all higher than those of the CK.The total weight of spinach plants increased linearly with the application rate of bioorganic fertilizer increasing among treatments,while the leaf area fluctuated with the increase of bioorganic fertilizer concentration among various treatments.The average root volumes and average diameters of treatments applied with bioorganic fertilizer at different rates were all higher than those in the CK,but the average root length showed a different trend.The average root length was higher in the CK than in various bioorganic fertilizer treatments in the early growth period,but the differences of various treatments from the CK gradually decreased in the middle period,and in the later period,the root length of spinach treated with organic fertilizer gradually exceeded the CK.[Conclusions]This study provides a theoretical basis for the rational application of bioorganic fertilizers in spinach production. 展开更多
关键词 SPINACH Bioorganic fertilizer Root system total weight of plants
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An Interconnection between Elevated SCC Levels in Milk around the First Artificial Insemination and Pregnancy Rate in Dairy Cows
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作者 Găvan Constantin 《Open Journal of Animal Sciences》 2023年第4期529-538,共10页
The aim of this study was to evaluate the impact of the somatic cell count (SCC) levels measured at 28-test-day intervals or pregnancy rate at the first artificial insemination of Holstein Friesian cows. All necessary... The aim of this study was to evaluate the impact of the somatic cell count (SCC) levels measured at 28-test-day intervals or pregnancy rate at the first artificial insemination of Holstein Friesian cows. All necessary information was taken from test day and farm records. Levels of SCC in milk, 30 days before, and 30 days after the first artificial insemination (FAI) date were divided into 4 categories and their interconnection with pregnancy rate (PR) at FAI was evaluated by applying logistic models. A SCC threshold of 150.000 cells/ml of milk was used to differentiate uninfected udders and infected udders of Holstein Friesian cows. A level of SCC > 150.000 cells/ml in milk, and a level of SCC < 150.000 cells/ml before and after FAI respectively were considered udders with new infections. A level of SCC > 150.000 cells/ml in milk before FAI as well as after FAI, was considered chronically infected udders or subclinical intramammary infections (IMI). Data from 792 FAIs from farm and test day records over a 4-year period (2019-2022) were evaluated. The outcome of this study revealed that the risk for low PR at the first AI was increased in cows with infected udders (OR = 1.33, CI 0.99 - 1.78), compared with uninfected udders. Increased levels of SCC after FAI had a negative effect on PR, while before FAI was not affected. To achieve a good PR, mastitis control measures must be fully adopted to a large extent around the first AI. 展开更多
关键词 Somatic Cell Count fertility Pregnant rate Test-Day-Milk Data
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Optimum Application Rate of Nitrogen in Summer Peanut in Southern Shandong Area
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作者 Hongjie TANG 《Asian Agricultural Research》 2023年第3期34-36,共3页
[Objectives]To study the effect of nitrogen(N)on the growth demand of summer peanuts under a certain level of phosphorus and potassium fertilizers,and to carry out experiments on nitrogen fertilizer control of summer ... [Objectives]To study the effect of nitrogen(N)on the growth demand of summer peanuts under a certain level of phosphorus and potassium fertilizers,and to carry out experiments on nitrogen fertilizer control of summer peanuts.[Methods]Four treatments were set up in the experiment:no-nitrogen plot(N 0P_(4)K_(4)),optimized nitrogen plot(N_(7)P_(4)K_(4)),70%optimized nitrogen plot(N_(5)P_(4)K_(4)),130%optimized nitrogen plot(N 9P 4K 4),repeated 3 times,and arranged in random blocks.The area of the plot was 42 m^(2),ridges were set between the plots,and protective rows of more than 1 m were set around the experimental site.The types of fertilizers were urea,superphosphate,and imported potassium chloride,and the variety of peanuts was Linhua 5.Except for the level of fertilization,other agricultural operations were the same,and soil sampling tests,field records,and yield testing were carried out according to the requirements of the plan.[Results]On the basis of 60 kg/ha of phosphorus and potassium fertilizer application,the optimum economical fertilizer application rate and the highest application rate of pure nitrogen were about 115.20 and 131.25 kg/ha,respectively.[Conclusions]This study is expected to provide a certain basis for the high-quality and high-yield summer peanuts in southern Shandong area. 展开更多
关键词 Southern Shandong area Summer peanut Nitrogen fertilizer Optimum application rate
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不同施氮量对春小麦灌浆速率和产量的影响 被引量:1
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作者 高新 汪烨霖 +8 位作者 朱泰武 李剑峰 王重 时佳 王春生 张宏芝 王立红 樊哲儒 张跃强 《新疆农业科学》 CAS CSCD 北大核心 2024年第2期310-317,共8页
【目的】研究不同施氮量对小麦籽粒灌浆进程的调控效应,分析滴灌条件下春小麦产量的提升潜力,为确定不同品质类型小麦品种适宜施氮量提供理论依据。【方法】以11个新疆审定的春小麦常规品种和1个现阶段正在培育的品系为材料,设置4个施... 【目的】研究不同施氮量对小麦籽粒灌浆进程的调控效应,分析滴灌条件下春小麦产量的提升潜力,为确定不同品质类型小麦品种适宜施氮量提供理论依据。【方法】以11个新疆审定的春小麦常规品种和1个现阶段正在培育的品系为材料,设置4个施氮水平处理,研究施氮量对不同春小麦品种(系)籽粒灌浆特性和产量的影响。【结果】不同施氮水平下小麦籽粒灌浆趋势均呈现为“S”型,随着施氮量的增加,小麦籽粒的干物质积累量达到最高籽粒千粒重后,积累的有效籽粒干物质重不增反降,但下降程度有所减缓。新春6号、新春37号、核春137表现为灌浆强势品种,新春11号、新春21号、新春29号表现为灌浆弱势品种。100 kg/hm^(2)低氮水平下,新春17号和核春615产量达最高水平;200 kg/hm^(2)中氮水平下,新春6号、新春11号、新春26号、新春29号、新春37号、新春39号、核春121和核春514共8个春小麦品种产量达最高水平;300 kg/hm^(2)高氮水平下,核春137和新春21号产量达最高水平。【结论】4个施氮水平下,最大灌浆速率V max与平均灌浆速率Vs均呈极显著正相关,平均灌浆速率Vs与灌浆总天数T均呈负相关。公顷产量Y与千粒重A、最大灌浆速率V max、平均灌浆速率Vs、达到最大灌浆速率所用天数T max、灌浆总天数T均呈正相关。 展开更多
关键词 小麦 氮肥 灌浆速率 产量
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人口结构变化、老龄化趋势及延迟退休对经济增长的影响 被引量:3
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作者 邹卫星 王莹 刘砚砚 《大连理工大学学报(社会科学版)》 CSSCI 北大核心 2024年第2期111-122,共12页
检验人口结构对经济增长的影响,预测人口总量及其结构的走势和老龄化的未来趋势,分析人口总量及其结构,尤其是老龄化趋势对经济增长的影响。研究发现:第一,劳动力数量和劳动力占比增加、人口抚养比下降会促进经济增长,在对经济增长的回... 检验人口结构对经济增长的影响,预测人口总量及其结构的走势和老龄化的未来趋势,分析人口总量及其结构,尤其是老龄化趋势对经济增长的影响。研究发现:第一,劳动力数量和劳动力占比增加、人口抚养比下降会促进经济增长,在对经济增长的回归中人口结构的解释力不及劳动力数量,但在预测未来时人口结构变化的影响力更大。第二,总人口会在低方案情况下已步入下降通道,如果总和生育率不快速提升的话,中国的老龄化程度在近50年将持续加深。第三,延迟退休可以减少老龄化对经济增长的负面冲击;提高生育率可以减缓老龄化程度,但在短期会抑制经济增长。延迟退休方案增加劳动人口越多,越能促进经济增长,延迟退休实施的力度越大,法定退休年龄越大,对老龄化的缓冲程度越大。如果男女每年延迟退休递增1年,分别最终延迟到70岁和65岁,在一些年份甚至可以完全抵消老龄化的抑制作用。 展开更多
关键词 老龄化 延迟退休 生育率 经济增长
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生育率回升的公共政策:约束、激励和扶持 被引量:5
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作者 王金营 张龙飞 《人口与发展》 CSSCI 北大核心 2024年第1期2-12,共11页
低生育问题成为中国未来面临的社会难题,为了治理低生育率问题,中央政府先后出台了“单独二孩”“全面两孩”和三孩政策,各地政府积极跟进,但收效甚微。如何才能够使生育率得到回升呢?由于生育是关乎亿万家庭和国家发展的大事,既是个体... 低生育问题成为中国未来面临的社会难题,为了治理低生育率问题,中央政府先后出台了“单独二孩”“全面两孩”和三孩政策,各地政府积极跟进,但收效甚微。如何才能够使生育率得到回升呢?由于生育是关乎亿万家庭和国家发展的大事,既是个体民生又是国家兴衰、民族复兴的公共性事务,生育问题也就成为具有公共性的问题。通过梳理国内外应对低生育率的公共政策实践经验,总结分析当前我国推升生育率政策效果不佳的原因。基于公共政策视域研究认为,需要通过制度、文化的建构和形塑,在约束不生“源头”的基础之上与“激励”和“扶持”个体生育需求相结合,系统性多维度协同促进生育率回升到适度水平。 展开更多
关键词 低生育率 生育政策 生育意愿
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我国籽实和饲草大麦土壤有效磷丰缺指标和推荐施磷量 被引量:2
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作者 孙洪仁 杨小可悦 +5 位作者 王显国 张运龙 杜雪燕 李林霞 冯泽娟 陶润志 《西南民族大学学报(自然科学版)》 CAS 2024年第1期1-8,共8页
为了给我国大麦测土施磷提供科学依据,采用“零散实验数据整合法”和“养分平衡-地力差减法新应用公式”,开展了我国大麦土壤有效磷丰缺指标和推荐施磷量研究.结果表明,我国大麦土壤有效磷第1~8级丰缺指标依次为≥40.7、24.2~40.7、14.4... 为了给我国大麦测土施磷提供科学依据,采用“零散实验数据整合法”和“养分平衡-地力差减法新应用公式”,开展了我国大麦土壤有效磷丰缺指标和推荐施磷量研究.结果表明,我国大麦土壤有效磷第1~8级丰缺指标依次为≥40.7、24.2~40.7、14.4~24.2、8.6~14.4、5.1~8.6、3.0~5.1、1.8~3.0和<1.8 mg/kg.当磷肥利用率15%~35%时,目标产量3~7.5 t/hm~2籽实大麦第1~8级土壤推荐施磷量分别为0、9~50、17~100、26~150、34~200、43~250、51~300和60~350 kg/hm~2;目标产量6~15 t/hm~2干草大麦第1~8级土壤推荐施磷量依次为0、9~50、17~100、26~150、34~200、43~250、51~300和60~350 kg/hm~2;目标产量15~45 t/hm~2青贮大麦第1~8级土壤推荐施磷量分别为0、7~51、15~102、22~153、29~204、36~255、44~306和51~357 kg/hm~2.本研究建立了我国籽实和饲草大麦土壤有效磷丰缺指标推荐施肥系统,为我国大麦测土施磷奠定了科学基础. 展开更多
关键词 大麦 测土施肥 土壤养分 有效磷 丰缺指标 施肥量
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生育文化、生育制度与生育率——兼论三孩生育政策及其配套支持措施的可能效果 被引量:3
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作者 陈友华 孙永健 《河海大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第1期12-28,共17页
随着中国少子老龄化程度的不断加深,如何促使生育率回升至适度水平成为政府和学界重点关注的议题,其中以三孩生育政策及其配套支持措施为代表的鼓励型生育制度和以“多子多福”为核心的传统生育文化被寄予厚望,希望借此帮助中国摆脱“... 随着中国少子老龄化程度的不断加深,如何促使生育率回升至适度水平成为政府和学界重点关注的议题,其中以三孩生育政策及其配套支持措施为代表的鼓励型生育制度和以“多子多福”为核心的传统生育文化被寄予厚望,希望借此帮助中国摆脱“低生育率陷阱”。然而,研究发现:中华文化圈国家或地区的生育率远低于其他国家与地区,而海外华人则是所在国生育率最低的族群之一,传统生育文化在现代社会已然发生了嬗变,对促使低生育率回升的作用已十分有限,取而代之的是“晚婚晚育少生优生甚至不婚不育”的现代生育文化,并形塑起一种内生性的低生育率机制。与此同时,欧洲和东亚国家通过构建鼓励型生育制度后依然深陷低生育率陷阱,无法有效刺激低生育率回升至适度水平。中国三孩生育政策及其配套支持措施的预期效果同样不容乐观,而生育文化、生育制度和生育率之间存在着十分复杂的互构关系,亟需从结构性和内生性的“文化—制度”视角去重新审视我国生育率转变的形成机制。 展开更多
关键词 生育文化 生育制度 低生育率 三孩生育政策
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我国籽实和饲草燕麦土壤有效磷丰缺指标与推荐施磷量初步研究 被引量:1
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作者 孙洪仁 王显国 +2 位作者 张运龙 杜雪燕 李林霞 《中国奶牛》 2024年第4期59-65,共7页
为了给我国燕麦测土施磷提供科学依据,本研究采用“零散实验数据整合法”和“养分平衡-地力差减法新应用公式”,开展了我国燕麦土壤有效磷丰缺指标与推荐施磷量研究。结果表明,我国燕麦土壤有效磷第1~8级丰缺指标依次为≥45、24~45、12... 为了给我国燕麦测土施磷提供科学依据,本研究采用“零散实验数据整合法”和“养分平衡-地力差减法新应用公式”,开展了我国燕麦土壤有效磷丰缺指标与推荐施磷量研究。结果表明,我国燕麦土壤有效磷第1~8级丰缺指标依次为≥45、24~45、12~24、6.2~12、3.2~6.2、1.7~3.2、0.9~1.7和<0.9mg/kg。当磷肥当季利用率为15%~35%时,目标产量1.5~6.0t/hm^(2)籽实燕麦第1~8级土壤推荐施磷量分别为0、4~40、9~80、13~120、17~160、21~200、26~240和30~280kg/hm^(2);目标产量4.5~15t/hm^(2)饲草燕麦第1~8级土壤推荐施磷量依次为0、6~50、13~100、19~150、26~200、32~250、39~300和45~350kg/hm^(2)。本研究建立了我国籽实和饲草燕麦土壤有效磷丰缺指标推荐施肥系统,为我国燕麦测土施磷奠定了科学基础。 展开更多
关键词 中国 燕麦 测土施肥 土壤养分 有效磷 丰缺指标 磷肥 施肥量
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基于模糊策略的水肥一体机控制可行性分析 被引量:2
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作者 胡伟强 《农机化研究》 北大核心 2024年第8期226-230,共5页
为进一步提高我国农业水肥一体机的综合作业效率,实现用水量与施肥量的混合浓度最优配置,以模糊策略为设计基点,针对整机控制展开可行性分析研究。以整机作业架构组成为基础,考虑灌溉施肥同步过程的水肥动态平衡,搭建正确的模糊策略模型... 为进一步提高我国农业水肥一体机的综合作业效率,实现用水量与施肥量的混合浓度最优配置,以模糊策略为设计基点,针对整机控制展开可行性分析研究。以整机作业架构组成为基础,考虑灌溉施肥同步过程的水肥动态平衡,搭建正确的模糊策略模型,进行系统的软件设计与硬件匹配。通过升级型水肥一体机实施灌施作业的效果验证,结果表明:基于模糊策略的水肥一体机控制系统整体试验过程顺畅,灌施的肥液均匀度可相对提升8.77%,系统对于各监测参数的响应度与稳定性均保持在90%以上,验证了设计的可行性;试验中节水率和肥料利用率分别较模糊策略应用前提升至91.70%和93.15%,整体灌施效率良好,说明了此模糊策略应用设计的优越性。研究结果对于实现水肥一体装备的智能控制水平向纵深提升具有很好的参考价值。 展开更多
关键词 水肥一体机 模糊策略 动态平衡 肥料利用率 纵深提升
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