Search

BackgroundAs the population ages, there has been a growing focus on the decline in fertility. Research has identified age and fertility history as the primary influencing factors. Nevertheless, there is a deficiency in fundamental data regarding the fertility status among different industries. ObjectiveTo investigate the fertility status and influencing factors among female workers aged 22-35 years in different industries. MethodsFrom July 2020 to February 2021, a cross-sectional survey was conducted using a staged sampling approach. This survey specifically targeted 22-35-year-old married female workers with a history of pregnancy in industries such as education, healthcare, finance, and telecommunications, totaling 22903 participants. The survey encompassed industry, demographic characteristics, pregnancy history, time to pregnancy (TTP), and other influencing factors. The influencing factors of decline in fertility were identified by chi-square test and Cox proportional hazards regression. Subsequent industry-specific Cox proportional hazards regression models were used to compared fertility decline patterns across a spectrum of industries after selected influencing factors were adjusted. ResultsAmong the 22903 respondents, 19194 valid questionnaires were collected, with a valid recovery rate of 83.8%. The cumulative pregnancy rates (CRP) of 1-6 months and 1-12 months for the 22-35-year-old female workers were 67.23% and 91.33% respectively. The multivariate analysis showed that region, age, education level, personal annual income, housework time, coping style, gravidity, parity, and spontaneous abortion were influencing factors of fertility decline (P

Copyright of Journal of Sichuan University (Medical Science Edition) is the property of Editorial Board of Journal of Sichuan University (Medical Sciences) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of School Administrators is the property of School Administration Research Association, R.O.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Poyang Lake is the property of Journal of Poyang Lake Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China has ranked first in the total output and use of chemical fertilizers in the world, as the increase of grain production. Generally, the single nutrient element of chemical fertilizer makes the fertilizer effect short and fast. If using for a long time, the fertilizer can cause soil hardening, soil fertility decline, even to decrease the quality of agricultural products. Alternatively, the organic fertilizer can be used to increase the soil organic matter and the permeability of soil, and thereby to ensure the high and stable yield of crops. However, the chemical fertilizer by adding more organic fertilizer behaves a high viscosity and fluidity, which makes it difficult to spread. In this study, a vertical spiral spreading device for the organic fertilizer was designed, in order to automatically crush organic fertilizer, and then to spread it wide. The specific processes were as follows: Firstly, the overall structure of device was preliminarily optimized. The vertical spiral spreading device for the organic fertilizer was mainly composed of the fertilizer spreading disc, spiral axis, beam, balance block, spiral blade, fertilizer spreading and crushing blade. The latter three were the key components of crushing organic fertilizer. Meanwhile, the fertilizer spreading and spiral blade were the key components of spreading organic fertilizer. A kinematic model of organic fertilizer in air was established to determine the influencing factors in the process of fertilizer spreading. The test factors included the rotational speed of spiral axis, inclination angle of fertilizer spreading disc, and screw pitch of spiral blade. The coefficient of variation and the fertilizer spreading width were set as the test indicators to evaluate the operation effect of the device, according to the fertilizer application standards. A field test was conducted at the Northeast Agricultural University in July, 2020. A rectangular area with the size of 10 m×8 m was set on the ground for data collection, and then the whole area was divided into many small squares with the size of 0.5 m×0.5 m for measurement. During the test, the fertilizer spreading width was first measured, and then the organic fertilizer was weighed, finally, where all test dataset was recorded. A Design-Expert 8.0.6 software was used to analyze the influence of each test factor and their interaction on each test indicator, and then a relationship was established between each test indicator and the regression equation of each test factor. An optimal combined range of all test factors was achieved via balancing the stability of the device and its economic considerations. A dataset was selected in the optimal range for the verification test: When the rotational speed of spiral axis was 385 r/min, the inclination angle of fertilizer spreading disc was 16°, and screw pitch of spiral blade was 360 mm, indicating that the coefficient of variation was 14.0%, and the fertilize spreading width was 8.1 m. The values were basically consistent with those of software calculation, indicating that can meet the national standards and the requirements of organic fertilizer application. The vertical spiral spreading device has good performance on spreading organic fertilizer, providing for a sound reference for the design and optimization of organic fertilizer spreader. [ABSTRACT FROM AUTHOR]

The TFR in Taiwan has declined more rapidly and pervasively than was expected. The TFR is a hypothetical measure, which can be influenced by two distinct parts: a 'quantum' component and a 'tempo' component. 'Many countries' 'desired children number' is kept at 2, but the TFR is far below 2. Bongaarts and Fenny criticized the TFR due to the changes in the timing of childbearing. Therefore, they announced the B-F method to shed the timing effect in order to more reliably capture fertility. However the tempo-free TFR method still can't represent the reality of fertility; we have to make use of other measures. We employed Li and Wu's SVD model and Schoen's ACF method to adjust the 1980-2005 TFR in Taiwan. The output of the ACF method was closer to the CFR. Both findings of the B-F method and ACF measure indicated that the TFR in Taiwan was above 1.3, the lowest-low fertility level. But the adjusted TFRs still did not reach 2. [ABSTRACT FROM AUTHOR]