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Recent changes in marital and extramarital fertility according to ethnicity in Kazakhstan Saule Dyussupova Abstract Contemporary Kazakhstan has experienced different social and political changes since being an independent country. These changes influenced demographic processes such as fertility. The number of live births per one woman has altered, but what were the changes among ethnicities and what type of fertility has changed more: marital or extramarital? To answer these questions more sizable ethnicities in Kazakhstan, which are Kazakhs, Russians, Ukrainians and Uzbeks were chosen. After examining the trends for the above mentioned ethnicities, their demographic positions in marital and extramarital fertility were explained. Meanwhile, despite the fact that the social-cultural attitudes of each ethnicity differ from each other, the tendency in marital fertility was going up among all ethnicities and in case of extramarital fertility, mostly among non and mixed traditional ethnicities was going down. Thus, based on the results of the research, the author has concluded the following: after the stabilization of economic and political conditions in the country the number of marital births increased, whereas traditional ethnicity (Uzbek) has experienced the fastest increase in the proportion of extramarital...

Ten two hectare forest plots were established on two distinct reserves, one mainly on volcanic deposits and the other on sedimentary and alluvial soils. These were investigated for their site carrying capacity and species diversity in relation to edaphic factors, using accumulated basal area as the growth indicator. A soil survey was conducted in each reserve to classify the soil types at the series level. Five two hectare sites each reflecting different soil types were chosen from each reserve. All trees of 10 cm dbh and over were enumerated on each soil type and identified to species level. Fourteen tree species were selected for foliage sampling. A representative soil pit was dug for each soil type and the different horizons were sampled. In addition, ten composite samples were randomly selected to represent soil depths 0-15 cm and 15-30 cm. A complete physical and chemical analysis was carried out on the samples. The results clearly exhibited the influence of parent material on particle size distribution, soil colour, bulk density, porosity, moisture retention and soil chemical compositions. In addition the phosphate fixation problem was discussed. Soil fertility is governed by the parent material from which the soil is derived and is parallelled by the site carrying capacity of the tropical rain forest. Reserve of K was demonstrated to be the main growth limiting nutrient. This was well supported by both soil and foliage analyses data. The nutrients N and P also influence growth but in these cases consistent relationships with basal area were only established after removing some out-lying points. The available and exchangeable soil nutrients were found to be poor indicators of growth. There appears a possibility of using Shorea leprosula as indicator species for foliar analysis in order to assess site fertility. Certain physical properties such as bulk density, clay content, site gradient and available water also exerted some influence on the growth of the trees. Fertile sites contained less species than nutritionally poorer sites. The competition-domination-suppression phenomenon is put forward in explanation. The geological body from which soil is derived is more dominant in determining species diversity than is the soil series per se. On poor sites dipterocarp species are more diverse and they also grow better on lower gradients. Chance factor plays more of an indirect role in species diversity and is believed to be very critical (especially on fertile sites) in the regeneration of dipterocarp species.

A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science (Geographical Information Sciences and Remote Sensing) Johannesburg, 2017 / Soil organic carbon is considered as the most determining indicator of soil fertility. The purpose of this research was to predict the soil organic carbon in the Mokhotlong region, eastern of Lesotho using in situ spectral measurements and random forest regression. Soil reflectance spectra were acquired by a portable field spectrometer. The performance of random forest regression was assessed by comparing it with one of the most popular models in spectroscopy, partial least square regression. Laboratory spectroscopy measurements of the soil samples were analysed for assessing the accuracy of in situ spectroscopy based-models. The effect of the Savitzky−Golay first derivative in improving partial least square regression and random forest regression in both spectral data was also assessed. The results indicated that the random forest regression could accurately predict the soil organic carbon contents on an independent dataset using in situ spectroscopy data (RPD = 3.77, Rp2= 0.88, RMSEP = 0.64%). The overall best predictive model was achieved with the derivative laboratory spectral data using random forest with the optimum number of key wavelengths (RPD = 3.77, Rp2= 0.88, RMSEP = 0.64%). In contrast, partial least square regression was likely to overfit the calibration dataset. Important wavelengths to predict soil organic contents were localised around the visible range (400-700 nm). An implication of this research is that soil organic carbon can accurately be estimated using derivative in situ spectroscopy measurements and random forest regression with key wavelengths. / MT 2017

"Will highly educated women have more children in the future?" In this contribution, I address this question by looking at both fertility and fertility intentions; i.e., the number of children people plan to have over their reproductive lives. Intended births are highly correlated with actual births, and in low-fertility settings, childbearing has become associated with the couple's agency. On the other hand, education, which is a marker of income and social status, has remained an important driver of fertility choices. Hence, understanding the reproductive decision-making of women and men with low, medium, and high levels of education is crucial when seeking to determine whether - and if so, to what extent - there is scope for additional policy interventions aimed at raising fertility levels.

Thesis (Ph.D.)--The Catholic University of America, 1992. / Major Adviser: Che-fu Lee. Includes bibliographical references.

Demographic and sociological theories usually do not incorporate biological variable into their explanations. This dissertation addresses this void by examining the influence of age at menarche on age at first birth, the event of a first birth, and the number of children ever born (CEB). I expand on Demographic Transition theory by incorporating biology as one of the effects of modernization that has an effect on reducing fertility. Age at menarche decreases as a society modernizes. I use data from the 1995 Survey of Family Growth, Cycle V for the U.S., and the 1997 China Survey of Population and Reproductive Health. I further stratify the data into five race/ethnic groups: Chinese Han, Chinese minorities, U.S. Non-Hispanic Whites, U.S. Non-Hispanic Blacks, and U.S. Hispanics of Mexican origin. I use four different statistical methods to model my dependent variables: Ordinary Least Squares Regression, Cox Proportional Hazard Analysis, Poisson Regression, and Negative Binominal Regression. My first major finding is that the younger a woman is when reaching menarche, the younger she will be when giving birth to her first child. Second, the younger a woman is when reaching menarche, the longer the duration to a first birth and the less likely she is to experience a first birth. These two results are consistent in all the groups I analyze. Third, the younger a woman when reaching menarche, the fewer children she will produce. The U.S. Mexican-Origin women are an exception in this final outcome. It is well known that as a society modernizes, age at menarche decreases. Analyses in my dissertation indicate that as women’s ages at menarche decrease, their ages at giving birth to the first child also decrease, but their chances of having a first birth also decrease and their waiting time for having the first birth increases. Also, fertility will decline as age at menarche declines.

The goal of this dissertation is to contribute in three ways to the literature on son preference and fertility through a comparative perspective. First, I examine the impact of son preference on fertility in China and South Korea compared with the United States. The impact that a female birth has on the likelihood of a woman having another birth is of the most concern: Women who have one or two daughter(s) as previous child(ren) are expected to be more likely to experience the hazard of having a second or a third birth. Second, my dissertation attempts to examine the effects of women’s status on son preference if women’s education reduces son preference. Third, my dissertation examines son preference and fertility in the U.S. Even though the U.S. has never shown son preference regarding sex ratios at birth, recent research has shown this association to exist among poor Hispanics. My dissertation used data from a national sample, 2002 National Survey of Family Growth. The results showed that women in China and South Korea who had a daughter instead of a son as their first child had a higher hazard of having a second birth as expected. Moreover, the results showed that the hazard ratio of having a third birth for Chinese and South Korean women was almost four and five times more, respectively. As expected, the hazard ratios for the U.S. were not significant and thus did not support the hypothesis. And the more educated women who had a daughter(s) instead of a son(s) as their previous child(ren) were less likely to have a second birth, but not in the third birth. This means women’s education apparently does not reduce son preference in the case of the third birth. Thus, women’s education apparently has limited or no influence on the childbearing decision where son preference is strong. Third, Hispanic women with low socioeconomic status did not have a significant hazard ratio of having a higher order birth. Accordingly, the dissertation does not find any statistical evidence of American son preference at the national level.

A number of genes have been associated with variation in human spermatogenesis related to fertility. One of these, the Deleted in Azoospermia (DAZ) gene, exists as copies on two chromosomes, 3 and Y. The autosomal copy, DAZ-like (DAZL), has one RNA recognition motif (RRM) and is homologous to the DAZL gene found throughout the vertebrate lineage. There are four copies of DAZ on the Y chromosome with a pair at each of two sites. One pair contains a single RRM and the other has three RRMs. Human DAZ is homologous to genes in old world primates and ape Y chromosomes. Both DAZ and DAZL bind messenger RNAs at U-rich sequences near the poly-A tail in a manner that facilitates translation. Both are expressed in spermatogonia during the transition from mitotic cellular expansion through meiotic chromosomal reduction and during spermiogenesis. This study examined genomic variation in DAZ and DAZL, including deletion of DAZ from individuals with various levels of sperm cell production and mutations of DAZL in male partners of infertile couples. Deletions in DAZ are not as common in azoospermic men from central Texas as compared to other reports. Single nucleotide polymorphisms (SNPs) were identified in anonymous infertility patients, but were not located in the exons of the RRM. Proteins produced from transcripts encoded by genes from human DAZL, DAZL with SNPs within and outside the RRM, and a DAZ with single RRM were identified. Binding activity of DAZL to mRNA was confirmed using a microarray method, and mRNA from human testes was screened to identify at least 1,313 mRNA potential targets for DAZL. These targets were involved in ribosome construction, pyruvate metabolism, cell cycle control, and proteasome function. Variations in binding of protein to a high and a low bound target mRNA were demonstrated between protein constructs of DAZL, DAZL with mutations, and DAZ. Binding of DAZL to mRNA was also confirmed using electrophoretic mobility shift assays. With materials and procedures developed during this study, comparisons of genetic variants of DAZ and DAZL can be performed to identify mechanisms responsible for structural and functional differences in control of spermatogenesis.