Reproductive compatibility between populations of the citrus red mite,Panonychus citri (McGregor ) (Acarina: Tetranychidae)

Summary Reproductive compatibility was studied among populations of different types of the citrus red mite,Panonychus citri (McGregor), i.e., the diapausing type from pear (DP), the non-diapausing type from citrus (C) and that from pear (NP). Copulation was also observed between mates of different types (DP and C). Only in crosses between C ♀ and DP ♂, was copulation occasionally broken off prematurely; duration of copulation varied considerably between pairs and the average duration was much shorter than that between DP ♀ and C ♂ and than that in crosses between mates of the same types. No F₁ adult females were produced at all from crosses between DP and C, showing that there was a complete reproductive isolation between the two types. There was a significant reciprocal difference in the egg hatchability and survival rate of immatures in the F₁ progeny; mortality in the eggs and that in the immature stage were significantly higher in crosses between DP ♀ and C ♂, as compared to those in the reciprocal cross. This suggested that fertilization may have occurred in the former cross, whereas it seemed that eggs were not fertilized in crosses between the C ♀ and DP ♂. The NP was compatible with the C, whereas it was completely incompatible with the DP. Thus, there was a complete reproductive incompatibility between the diapausing and non-diapausing type ofP. citri. This work was supported in part by Grant-in-Aid No. 60560049 from the Ministry of Education, Science and Culture, Japan.     

Kinship and Population Subdivision

The coefficient of kinship between two diploid organisms describes their overall genetic similarity to each other relative to some base population. For example, kinship between parent and offspring of 1/4 describes gene sharing in excess of random sharing in a random mating population. In a subdivided population the statistic F _st describes gene sharing within subdivisions in the same way. Since F _st among human populations on a world scale is reliably 10 to 15%, kinship between two individuals of the same human population is equivalent to kinship between grandparent and grandchild or between half siblings. The widespread assertion that this is small and insignificant should be reexamined.     

The association between husbands’ and wives’ labor market positions in the Netherlands

This study describes (1) the association between husbands’ and wives’ employment statuses and occupations in the Netherlands, (2) establishes possible trends in the association, and (3) explores to what extent the association can be attributed to educational homogamy. We use 12 waves of the Dutch Labor Force Survey (1994–2006), and use log-linear models to analyze the associations between the labor market positions of spouses. Overall, we find positive associations, implying that favorable positions are accumulated within households. For couples with children, the association between spouses’ employment status is negative, which means that they divide paid labor. Over birth cohorts, the association between spouses’ employment statuses becomes stronger, and between spouses’ occupational success remains stable. Education is an important contributor to the occupational association, but still half of the association between spouses’ success cannot be attributed to spouses’ education.     

Comparison of male adult population densities of the oriental and artocarpus fruit flies,Dacus spp. (Diptera: Tephritidae), in two nearby villages in Penang, Malaysia

Summary The populations of native male adult oriental fruit flyDacus dorsalis (Hendel) and artocarpus fruit flyD. umbrosus (F.) in two selected site (BU and SD) were estimated weekly by the capture-recapture technique using live traps baited with methyl eugenol. In BU where many varieties of fruit trees were grown, the estimated population densities ofD. dorsalis were between 980 and 3100 male flies per ha between May and July, 1984. During the same period, in SD where there were fewer number and varieties of fruit trees, the estimated population densities were between 300 and 1000 flies per ha. The estimated population densities ofD. umbrosus over the same period were between 570 and 1290 flies per ha in BU; and between 5 and 95 flies per ha in SD. Of a total 6828 markedD. dorsalis flies released only one fly (released 6 weeks earlier in BU) was caught in a different site.     

Internalized homophobia, lesbian identity development, and self-esteem in undergraduate women

This study examined the relationship between internalized homophobia, self-esteem, and lesbian identity development in 35 undergraduate women. Results indicated evidence of a strong relationship between the two identity development measures, the Stage Allocation Measure (SAM; Cass, 1984) and the Gay Identity Questionnaire (GIQ; Brady & Busse, 1994), and moderate relationships between identity development and internalized homophobia, between identity development and self-esteem, and between internalized homophobia and self-esteem. Implications for research and clinical practice are discussed.     

Estimating the impact of change in pre-pregnancy body mass index on development of Gestational Diabetes Mellitus: An Australian population-based cohort

BackgroundInternational studies examining maternal overweight and obesity have found GDM risk increases with increasing weight gain between pregnancies.AimThe study aimed to estimate the association between pre-pregnancy maternal body mass index (BMI), change in BMI between pregnancies and Gestational Diabetes Mellitus (GDM) amongst women with consecutive births in an Australian cohort.MethodsWe used a population cohort of women who had at least two consecutive singleton births between 2010 and 2017 in one NSW health district to investigate the risk of GDM in the pregnancy after the index pregnancy, BMI change between pregnancies and the impact of BMI change on risk of GDM.FindingsOf 10,074 women 1987 (16.7%) had no GDM in the index pregnancy but GDM in the subsequent one while 823 (8.2%) had GDM in both pregnancies. No change in BMI between pregnancies occurred in 47% of women, while 12% had a decrease and 41% an increase. After adjusting for socio-demographic characteristics and selected maternal and perinatal confounders, a reduction in BMI between births in women without GDM in the index pregnancy was associated with a 36% lower risk in GDM (aRR: 0.64; 95% CI: 0.49?0.85), while an increase in BMI was associated with increased risk of GDM with the greatest risk amongst those who gained 4+ kg/m² (aRR 2.27; 95%CI: 1.88–2.75).ConclusionInterpregnancy weight change is an important modifiable risk factor for the risk of GDM in a subsequent pregnancy. Clinical guidelines and health messages about interpregnancy weight change are important for all women.     

Safety and Home–School Relations as Indicators of Children Well Being: Whose Perspective Counts?

Recent attention to children’s well being has generated research showing that safety and home–school relations are two of the most important indicators of children’s well being. Recent studies have also demonstrated the consistent differences in perspectives between children and teachers and between parents and teachers in regard to home–school relations and between children and parents in regard to children safety. This paper reports findings from an exploratory study, conducted as part of the “Strong Communities” initiative in South Carolina, comparing between the three perspectives of children, parents, and teachers in regard to children both home–school relations and safety. The findings show significant differences regarding almost all items between the three groups. For example, teachers felt school and the way to and back from school were safer for children than how the children themselves felt. However, other patterns were found with regard to home–school relations. The article concludes with a discussion of the apparent weight given to each of these perspectives, possible explanations for the gaps found and its practical implications for social indicators usage.     

Religion as a determinant of marital fertility

This paper develops hypotheses about the effects of husbands‘ and wives‘ religious affiliations on fertility. The hypotheses are based on two central ideas. First, religions differ in their fertility norms and corresponding tradeoffs between the quality and quantity of children; differences in religious beliefs between husband and wife may thus lead to conflict regarding fertility decisions and possible resolution through bargaining. Second, a low level of religious compatibility between the spouses may raise the expected probability of marital dissolution and thereby decrease the optimal amount of investments in spouse-specific human capital. Analyses of data from the 1987–1988 National Survey of Families and Households conducted in the United States suggest that both of these effects play important roles in explaining the observed linkages between the religious composition of unions and fertility behavior. JEL classification: J1, J11, J13 Received February 17, 1995 / Accepted February 15, 1996     

Declines in Health and Support Between Parents and Adult Children: Insights from Diabetes

Population Research and Policy Review - We investigate associations between a diabetes diagnosis and financial and instrumental transfers between parents and adult children. Data are from...     

Economic Theory and Subjective Well-being: Mexico

Several studies have been conducted on the topic of well-being. Most of them, however, have been done in industrialized countries where income is distributed relatively more equitatively and the population tends to be more homogeneous. This paper studies the relationship between subjective and economic well-being in Mexico, a country where the economic differences among the population are more clearly marked.

According to the economic definition of well-being, higher levels of income are associated with higher levels of well-being through greater levels of material consumption. Taking into consideration this definition, it is worth asking just how important income is for an individual's happiness?Existing studies in psychology have found a positive correlation between economic well-being (socioeconomic status) and subjective well-being (happiness). However, this positive relationship is weak and a large percentage of human happiness remains unexplained.

Although the mentioned studies make a good approximation of the existing relationship between income and happiness, the characteristics or specification of the function that generates the relationship between these two variables is often assumed to be linear and positive. The main objective of this paper is to investigate further the relationship between subjective and economic well-being. In this study different specifications and approaches are used to approximate the relationship between these variables.

An empirical analysis is made from the results of a survey conducted in two Mexican cities. The investigation studies the impact of demographic, social, and economic variables on subjective well-being in Mexico. Several hypotheses are tested to identify the relationship between household income and individual well-being. It is found that income does not have a strong influence on neither well-being nor on the probability of happiness. However, people tend to overstress the impact that additional income would have on their subjective well-being. This fact could explain the importance that people place on increasing their income level, and it could possibly explain the relative sense of dissatisfaction once a higher income level is achieved.

The relationship between income and the sense of basic need satisfaction is also explored. A main assumption in economic theory suggests the existence of a direct relationship between these variables; however, empirical results show this relationship to be extremely weak. Results indicate that subjective well-being is positively related to the sense of basic need satisfaction but not to income.

     

The distinction between affect and cognition

The distinction between affect and cognition was studied in a sample of early breast cancer patients. As assumed by Mckennell (1978) the change experienced led to a level of affect that was lower than the level of cognition and an increased discrepancy between these two components of quality of life within the first year after surgery. Cognition was stable over time, whereas affect improved (p<0.05). The relation between concommitants of disease and treatment and the types of affect-cognition combination were explored.     

On testing Easterlin's hypothesis using relative cohort size as a proxy for relative income

Measures of Canadian fertility (total fertility rate and fifteen-year age-specific fertility rate F_15–29) and relative cohort size (population aged 30–64 years divided by population aged 15–29 years) show a close co-movement between 1940 and 1976 but record a marked departure since then. The application of cointegration techniques to these series (1921–1988) shows that they do not form an equilibrium relationship even over the period 1940–1976. Contrary to the expected relationship between relative cohort size and relative income, income data by age groups show that there is no tight relationship between them. The absence of an equilibrium relationship between relative cohort size and fertility, therefore, does not necessarily imply that Easterlin's hypothesis is false.I would like to thank Paul Maxim for allowing me to use his data set for this analysis. My thanks are also due to Peter Smith and three anonymous referees for their constructive comments on this work.     

It’s Not Me,It’s You: Perceptions of Partner Body Image Preferences Associated With Eating Disorder Symptoms in Gay and Heterosexual Men

This study explored perceptions of partner body image preferences and symptoms of disordered eating in gay and heterosexual men. Participants were male college students (n = 201; M age = 20.46), and over one third identified as gay. We compared discrepancies between participants’ current and ideal body type and participants’ current body type and the body type they believed they should have to attract a dating partner. For gay men, the discrepancy between their current body and the body they believed they should have to attract a dating partner was significantly greater than the discrepancy between their current and ideal body types. In gay and heterosexual men, the discrepancy between current body and the body they believed they should have to attract a dating partner predicted eating, shape, and weight concern. Results suggest that perceptions of partner body image preferences may contribute to eating disorder pathology in men.     

Do Measured and Unmeasured Family Factors Bias the Association Between Education and Self-Assessed Health?

The association between educational attainment and self-assessed health is well established but the mechanisms that explain this association are not fully understood yet. It is likely that part of the association is spurious because (genetic and non-genetic) characteristics of a person’s family of origin simultaneously affect one’s educational attainment and one’s adult health. In order to obtain an unbiased estimate of the association between education and health, we have to control for all relevant family factors. In practice, however, it is impossible to measure all relevant family factors. Sibling models are particularly appropriate in this case, because they control for the total impact of family factors, even if not all relevant aspects can be measured. I use data on siblings from a US study (MIDUS) and Dutch study (NKPS) to assess the total family impact on self-assessed health and, more importantly, to assess whether there is a family bias in the association between educational attainment and self-assessed health. The results suggest that there is a substantial family effect; about 20% of the variation in self-assessed health between siblings can be ascribed to (measured and unmeasured) family factors. Measured family factors, such as parental education and father’s occupation, could account only for a small part of the family effect. Furthermore, the results imply that it is unlikely that there is substantial bias due to family effects in the association between education and self-assessed health. This strengthens the conclusions from prior studies on the association between education and self-assessed health.     

Belief in the Afterlife,Death Anxiety,and Life Satisfaction of Buddhists and Christians in Thailand: Comparisons Between Different Religiosity

This research studied belief in the afterlife, death anxiety, and life satisfaction, of Buddhists and Christians in Thailand. The aim of this research was to compare the variables of interest between high and low religiosity within their religion. There were two studies of 800 participants. Study 1 compared between Buddhists and meditated Buddhists in terms of the above and related variables. Study 1 had 577 participants, comprised 532 Buddhists and 45 meditated Buddhists who had already been meditating for 6 months and just finished 1-h meditation. Study 2 compared between Christians and meditated Christians who had intense involvement in religious discipline and just finished religious attendance. Study 2 had 223 participants, comprised 175 Christians and 48 meditated Christians. The results show that meditated Buddhists had more belief in the afterlife and more frequency of going to temple than Buddhists (p < .001 and p = .001, respectively). However, life satisfaction and death anxiety between Buddhists and meditated Buddhists were not significantly different (p = .349 and p = .121, respectively). Meditated Christians had less death anxiety than Christians (p < .001). Meditated Christians had more belief in the afterlife and more frequency of going to church than Christians (p < .001). However, life satisfaction between Christians and mediated Christians was not significantly different (p = .607).

     

Interannual fluctuations in recruitment and growth of the sardine,Sardinops melanostictus, in the sea of Japan and adjacent waters

Recruitment and growth of the sardineSardinops melanostictus fluctuated markedly in the Sea of Japan and adjacent waters between 1978 and 1993. Stock size was calculated using Virtual Population Analysis and average body length in each age class was determined by the number of annual rings on the scales. There is an inverse correlation between average water temperature at a depth of 50 m in the coastal area of the mainland of Japan in winter (January to March) and recruitmentR defined as the number of individuals at 1 year old. There is also an inverse correlation between spawning stock sizeE and reproductive success in (R/E). A multiple regression model using spawning stock size and water temperature in winter as independent variables can explain 73% of variance in reproductive success. It suggests that both density-dependent and density-independent factors perform important roles determining reproductive success. There is an inverse correlation between body length and stock size and this suggests that there is a density-dependent effect on the growth of the sardine.     

Xena and the Warrior Poets: Audre Lorde,Monique Wittig,and the myths of lesbian origins

This paper explores the connections between the television show Xena: Warrior Princess, and the myths of lesbian origins which were created by a loose collection of writers known as warrior poets. It argues that the show contains significant components of those myths as imagined by Audre Lorde and Monique Wittig. In particular, both show and myths share the presence of irresponsible gods; ideas of destiny; and women-centredness, which includes parthenogenesis, love, desire, and rivalry between women. The paper suggests that the transformative power of the show comes largely from the erotic connection between women that is at the core of these lesbian origin myths.     

The Interrelationship between Fosterage,Schooling, and Children’s Labor Force Participation in Ghana

This paper examines the interrelationship between fosterage, school attendance, and children’s employment in Ghana. Using the 1991/1992 Living Standards Survey data on children aged 7–17 years and a trivariate probit model, the paper demonstrates that ignoring the linkages between these outcomes leads to downward-biased estimates of the impact of fosterage on schooling and upward-biased estimates of the impact of fosterage on work. Gender and age are important considerations in family decisions regarding children’s activities. Joint decision-making is more common for girls aged 12–17 than for boys of a similar age. A significant negative correlation is also observed between the likelihood of employment and the likelihood of school attendance among adolescent girls.     

The relationship between leisure and life satisfaction: application of activity and need theory

The purpose of this study was to better understand the complex relationship between leisure and life satisfaction. Components of two distinct, but potentially integrative, theoretical frameworks (i.e., activity theory and need theory) predicting the relationship between leisure and life satisfaction were tested with a sample of residents from a Midwestern community (n = 633). Findings provided support for both theoretical perspectives, but stronger relationships were found between satisfied needs than with participated activities. In spite of these findings, the various inconsistencies within the two theoretical frameworks suggest that future research is needed.