Thesis (M.S.)--Texas State University-San Marcos, 2007. / Vita. Includes bibliographical references (leaves 56-59).

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At the heart of long term sustainable soil management is chemical fertility through the retention of exchangeable cations. Many current concepts of cation exchange and its relationship with base cation availability remain unchanged over the past century. Despite considerable advancements in analytical techniques many methods used today would be familiar to our forefathers. Comparative studies were undertaken in this thesis to understand how techniques to measure exchangeable soil ions could be enhanced and matched to defined scenarios. The total amount of cations that can be retained electrostatically on soil surfaces is termed the cation exchange capacity (CEC). An ability to systematically and consistently measure CEC is an essential step in soil characterisation. Compulsive exchange methods (using either 1.0 M NH4OAc or 0.05 M BaCl2) at a fixed pH value for determining CEC were scrutinised but acknowledged to be prone to systematic artefacts. The relationship between soil pH, soil texture and CEC was soil specific. When the batch method was compared with the column leach method, the former was more consistent for all soils. For calcareous soils BaCl2 was more suitable but NH4OAc was more generally applicable. The CEC was consistently significantly greater by the compulsive technique when compared with the effective method. The NH4OAc extraction method was applied to soils contaminated with potentially toxic elements (PTEs). The exchangeable concentration of PTEs correlated with total PTE loading. However, the exchangeable Ca decreased with amendment rate confirming an exchange of sites by PTEs. The compulsive technique extracted PTEs that were significantly 2 negatively correlated with soil basal respiration, phosphatase activity, potential nitrification rate (PNR) and the soil microbial biomass carbon. This confirms that of this method is evaluating the bioavailable/bioreactive fraction. Soil cation exchange capacity and exchangeable base cations increased commensurate with the amendment loading of bentonite and charcoal. The exchange capacity was also soil specific. Following amendments, the exchange capacity was higher after six weeks than after thirty weeks. This means that the amendment performance became impaired with time perhaps as the fine soil particles coated the ameliorant causing a decline in CEC. The difference between the effective and compulsive CEC was described as the calculated CEC. This was very sensitive to soil pH and was confirmed in a detailed study at a site where pH plots were amended over a five decade period. As pH rose, so did the exchangeable fraction of Ca, Mg and K. As the pH declined, Al, Fe and Mn exchangeability increased. Extraction techniques must be sympathetic of the soil pH value. The quantification and characterisation of exchangeable cations remains as fundamental a component of soil science today as it was a century ago.

Background: The influence of religion on demographic behaviors has been extensively studied mainly for Abrahamic religions. Although Buddhism is the world´s fourth largest religion and is dominant in several Asian nations experiencing very low fertility, the impact of Buddhism on childbearing has received comparatively little research attention. Objective: This paper draws upon a variety of data sources in different countries in Asia in order to test our hypothesis that Buddhism is related to low fertility. Methods: Religious differentials in terms of period fertility in three nations (India, Cambodia and Nepal) and cohort fertility in three case studies (Mongolia, Thailand and Japan) are analyzed. The analyses are divided into two parts: descriptive and multivariate analyses. Results: Our results suggest that Buddhist affiliation tends to be negatively or not associated with childbearing outcomes, controlling for education, region of residence, age and marital status. Although the results vary between the highly diverse contextual and institutional settings investigated, we find evidence that Buddhist affiliation or devotion is not related to elevated fertility across these very different cultural settings. Conclusions: Across the highly diverse cultural and developmental contexts under which the different strains of Buddhism dominate, the effect of Buddhism is consistently negatively or insignificantly related to fertility. These findings stand in contrast to studies of Abrahamic religions that tend to identify a positive link between religiosity and fertility.

BACKGROUND Consanguinity - or marriage between close blood relatives, in particular first cousins - is widely practised and even socially encouraged in many countries. However, in the face of fertility transition where the number of cousins eligible to marry declines, how might such constraints on consanguinity develop in the future? OBJECTIVE Numerous studies have stated that the practice cannot continue at present levels and in its present form in the face of fertility transition. However, the future impact of fertility transition on availability of cousins to marry has not yet been quantified. METHODS We perform a simulation exercise using past and projected net reproduction rates (NRRs) derived from the UN. We calculate the average number of cousins of the opposite sex as a function of the average number of children, the average probability of an individual having at least one eligible paternal cousin of the opposite sex, and conclude with an examination of constraints on consanguineous marriage in selected countries under different fertility assumptions. RESULTS Current and projected fertility levels in Middle Eastern countries will create challenging constraints on the custom once today's birth cohorts reach marriageable age. CONCLUSIONS Either consanguinity prevalence will diminish significantly, or the institution will be forced to adapt by becoming more coercive in the face of reduced choice or at the expense of other social preferences (such as for an older groom wedding a younger bride). Fertility decline affects prospects for social change not only through its well-known consequences for mothers but also through shaping marriage conditions for the next generation.

Depending on whether the global level of fertility is assumed to converge to the current European TFR (~1.5) or that of Southeast Asia or Central America (~2.5), global population will either decline to 2.3-2.9 billion by 2200 or increase to 33-37 billion, if mortality continues to decline. Furthermore, sizeable human populations exist when the 'voluntary chosen' ideal family size is heavily concentrated around one child per woman with TFRs as low as 0.6-0.8. However, the UN population projections to 2300 use a much narrower band of possible future TFRs. If the two-child norm is not necessarily the end-point transition, what would be the consequences of the currently reported low fertility rates being sustained and becoming widespread? We present new projections for 13 IPCC world regions with scenarios calculated on the basis of regular cohort-component projections by age and sex in single-year time steps up to 2300, each based upon a much broader set of fertility assumptions than currently employed. We create three mortality scenarios based upon maximum life expectancies of 90, 100, 110, as well as a series of "Special" scenarios. Even under conditions of further substantial increases in life expectancy, world population size would decline significantly if the world in the longer run followed the examples of Europe and East Asia. In contrast to Malthusian disaster scenarios, our exercise illustrates the distinct possibility of significant population shrinking associated with increasing life expectancy and human well-being.

The role of work-family reconciliation policies in female employment and fertility recuperation in selected EU member states Kamila Utegenova Abstract Currently an increasing number of parents, in particularly women, experience conflict in work-family balance, which significantly affects the level of fertility in developed countries. The European Council is actively involved in solving this problem, since the general welfare of the country may directly depend on the balanced population reproduction. This work is aimed at identifying the effects of the special measures taken to improve women's employment efficiency - in the spheres of childcare arrangements, parental leave and gender equality. Keywords: fertility, employment, work-life balance, European Union member states

Indiana University-Purdue University Indianapolis (IUPUI) / During the last two years, women of reproductive age (WRA) have experienced uncertainty about the COVID-19 vaccine, particularly as it relates to reproductive health (e.g., fertility) due to the COVID-19 infodemic. Because WRA are a pivotal population in pandemic control, it is important to understand how WRA manage vaccine-related uncertainty. Uncertainty management theory (UMT) considers the complexities of uncertainty, acknowledging that individual appraisals of, and responses to, uncertainty may vary from person to person and evolve over time. This study examined factors contributing to WRA’s hesitancy to receive the COVID-19 vaccine, including uncertainty about potential side effects, concern about safety and efficacy, and conflicting information. WRA most frequently felt neutral towards their uncertainty; however, negative emotional responses to uncertainty played an influential role in many WRA’s responses to uncertainty (e.g., avoiding information, seeking information, receiving the COVID-19 vaccine). The findings of this study provided insight on how WRA have experienced uncertainty about the COVID-19 vaccine, including their emotional responses to and subsequent appraisals of their uncertainty which ultimately influenced their responses.

Fertility is classified as one of the most limiting aspects plaguing successful mammalian reproduction. In addition, sequential collaborations between a quality spermatozoon and oocyte are essential for successful fertilization, and key in subsequent embryonic development. Male fertility has been consistently declining in mammals. Currently, cost efficient and reliable methods predicting fertility are lacking. As a result, the objectives of this research were to establish molecular markers to predict male fertility by determining sperm cellular phenotype variability among bulls of varying fertility by focusing on the roles of protein markers, TUBB 2C, HSP10, HXK1 and SOD1; establish expression characteristics of ITGB5 protein in sperm, oocytes and early embryos; and finally; determine expression level variability and functions of miRNAs, miR-214 and miR-25 in sperm from bulls of varying fertility. We found that while no significant differences occurred in the expression levels of our proteins in high and low fertility bulls, correlations were discovered between SOD1, HSPE1 and fertility, and subpopulations consisting of intact, partially damaged and completely damaged acrosomes in flow cytometry and microscopy experiments were identified. Results also showed that expression levels of itgb5 were significantly higher in the 2-cell bovine embryos, followed by the 8-16 cell embryos, however, no significant difference in expression levels were noted for the morula and blastocyst stages as compared to the MII oocytes. Phylogenetic analyses confirmed conservation of itgb5 across multiple species, further indicating its potential importance and functional role(s) in fertilization and potential as a marker of fertility. Micro-RNA studies revealed differential expression levels of miR-25 and miR- 214 for all samples analyzed, yet there was no significant difference in expression of the microRNAs when comparing high fertility and low fertility bulls. Also, processes associated with spermatogenesis, such as cellular growth, transduction, translation and transformation which are necessary for fertility, were shown to be targets of miR-214 and miR-25. These results imply that sperm proteins and sperm-bore miRNAs could potentially be targeted as molecular markers of fertility. The findings are important because they illuminate the molecular and cellular underpinnings of gamete quality that influence successful fertilization and early development.

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