Relationship between female body size and demographic parameters inBactrocera Malaysian A (Diptera: Tephritidae)

Summary The effect of body size, as measured by the head width, of the femaleBactrocera sp. Malaysian A (kept separately in sexual pairs) on the demographic parameters was investigated in the laboratory under ambient conditions of 28–30°C, 78–85% RH and natural photoperiod. Body size was shown to influence significantly all the demographic parameters. The expectation of life of females at eclosion from pupae was respectively for head widths of 1.6, 1.8, 1.9, 2.0 and 2.1 mm: 76.2, 73.4, 73.8, 102.4 and 115.2 days. The mean number of eggs laid per female in its life time was respectively: 86.4±48.7, 181.8±56.1, 229.7±72.6, 364.3±69.4 and 477.5±109.3 which was significantly different from one another (F=3.73,P<0.05) especially the two smaller sizes from the two larger sizes. The regression line for total eggs laid (Y) against head width (X) wasY=785.2X−1208.7 (R ²=0.35,P<0.001). The net reproductive rate (R ₀) was respectively 15.8, 34.0, 43.5, 66.9 and 88.8 eggs, while the intrinsic rate of increase (r) was respectivley 0.0435, 0.0538, 0.0670, 0.0665 and 0.0711. The results confirm that for mass rearing purposes, larger females which produce more offspring are to be preferred.     

Large gaps in the quality of healthcare experienced by Swedish mothers during the COVID-19 pandemic: A cross-sectional study based on WHO standards

Background and ProblemExisting healthcare systems have been put under immense pressure during the COVID-19 pandemic. Disruptions in essential maternal and newborn services have come from even high-income countries within the World Health Organization (WHO) European Region.AimTo describe the quality of care during pregnancy and childbirth, as reported by the women themselves, during the COVID-19 pandemic in Sweden, using the WHO ‘Standards for improving quality of maternal and newborn care in health facilities’.MethodsUsing an anonymous, online questionnaire, women ≥18 years were invited to participate if they had given birth in Sweden from March 1, 2020 to June 30, 2021. The quality of maternal and newborn care was measured using 40 questions across four domains: provision of care, experience of care, availability of human/physical resources, and organisational changes due to COVID-19.FindingsOf the 5003 women included, n = 4528 experienced labour. Of these, 46.7% perceived a poorer quality of maternal and newborn care due to the COVID-19. Fundal pressure was applied in 22.2% of instrumental vaginal births, 36.8% received inadequate breastfeeding support and 6.9% reported some form of abuse. Findings were worse in women undergoing prelabour Caesarean section (CS) (n = 475). Multivariate analysis showed significant associations of the quality of maternal and newborn care to year of birth (P < 0.001), parity (P < 0.001), no pharmacological pain relief (P < 0.001), prelabour CS (P < 0.001), emergency CS (P < 0.001) and overall satisfaction (P < 0.001).ConclusionConsiderable gaps over many key quality measures and deviations from women-centred care were noted. Findings were worse in women with prelabour CS. Actions to promote high-quality, evidence-based and respectful care during childbirth for all mothers are urgently needed.     

A comparative study of the searching efficiencies of a parasite and a hyperparasite

Summary The searching efficiencies of a primary parasite (Diaeretiella rapae (McIntosh)) and a hyperparasite (Alloxysta brassicae (Ash.)) were investigated and compared. In both species, at all parasite densities, there was a curvilinear relationship (P<0.001) between the number of hosts parasitised and the host density. A linear regression (loga=logQ−m logP) was fitted for log area of discovery against log parasite density (P<0.001). The area of discovery for its immediate (i.e. primary) host (viz.Diaeretiella for the hyperparasite and aphid forDiaeretiella) is lower in the hyperparasite than in the primary parasite. InDiaeretialla both the searching efficiency and the mutual interference constant increased (but not significantly,P>0.05) in the presence of its males.     

Ecological and Motivational Determinants of Activation: Studying Compared to Sports and Watching TV

How can we enhance activation? Studying shouldbe a challenging, yet rewarding activity forstudents who intend to graduate. The Flowtheory (Csikszentmihalyi, 1990, 1997) predictsthat differential levels of perceived challengeand skill (flow) are related to optimizedmental states and increased activation.However, the influence of concurrent mentalstates and specific environmental cues for thisstate of optimal experience is unknown. In thisstudy we explore the contextual and subjectivedeterminants of flow in relation to activationin studying, and compare this with sports andwatching TV or listening to the radio. Method: 43 undergraduate students at theUniversity of Maastricht were assessed with theExperience Sampling Method for one week(Delespaul, 1995). At random moments 10 timeseach day subjects evaluated the social context,activities, and mood states. Analyses were donewith multilevel random regression techniques.Results: We replicated the predictedflow-related patterns in activation andemotions. While overall activation wasincreased in high challenging moments(β = 0.51; 95% CI: 0.36, 0.19), thiseffect was less pronounced during study(β = ?0.16; 95% CI: ?0.25, ?0.07). Skillslevels did not affect activation(β = ?0.01; 95% CI: ?0.06, 0.05).Concurrent emotions were independently andadditionally related to activation(Δχ² ₍₄₎ = 117.12,p < 0.0001). Unexpectedly, activation increasedwith demotivation (β = ?0.12; 95% CI:0.16, 0.07). We found highly significant andadditional effects of context for all theactivities (study: χ² = 732.63;p < 0.0001; R² = 0.30; active leisure:χ² = 753.40; p < 0.0001; R² = 0.31;and passive leisure: χ² = 555.86;p < 0.0001; R² = 0.24). Conclusions. TheFlow theory is a valuable model leading topredictions of optimal experience as well asactivation. However, the dynamics of activityengagement are more complex and related toconcurrent emotions and context. In the Dutchstudent culture, escaping boredom or compulsoryduties seems to drive individuals more thanpursuing flow.     

Health-Related Quality of Life Among Abused Women One Year After Leaving a Violent Partner

This is the first follow up study measuring quality of life among abused women who have left their abusive partner. The women (n = 22) answered a questionnaire while staying at women’s shelter and one year later. The aim was to examine long-term effects of intimate partner violence against women on health-related quality of life. Health-related quality of life was measured using the SF-36 Health Survey and the WHOQOL-BREF. The meantime for living in a violent partnership was 11 years, most of the women had children under 10 years living with them, low income and were on sickness absence or disability pension. About half of the women had experienced threats of violence and 6 had experienced violent acts after leaving their partner. SF-36 scores after one year were significantly better in vitality (t-test, P < 0.001), mental health (t-test P < 0.001) and social domains (t-test, P < 0.04). WHOQOL-BREF scores did not change significantly from baseline, showing that the SF-36 showed more responsiveness in this population. Regression analysis showed that serious physical violence reported at baseline predicted significantly less improvement in physical and mental health and role-emotional in the SF-36 and in social relationships and environmental health in the WHOQOL-BREF. High psychological violence at baseline predicted significantly less improvement in mental health in the SF-36 and in social relationships and environmental health in the WHOQOL-BREF.     

Relationship between surplus energy and body weight in fish populations

Summary This paper theoretically analyses the relationship between surplus energy, which is available for either somatic growth or reproduction, and body weight. From the data of metabolism and growth of the biwamasu,Oncorhynchus rhodurus, obtained by Miura et al., a Bernoulli's differential equation is induced to represent the relationship between body weight and the sum of surplus energy and active metabolic rate. Solving this equation gives the amount of surplus energy,f(W_x), as follows:f(W_x) = (αW _x ^1−γ +β^1−γ)^1/(1−γ)−W_x, in which α, β and γ are constants andW _x is body weight at agex. The function is applied to ten fish populations and consequently it is found to be useful for a wider age range and a wider variety of fishes than the conventional function.     

The Relationship between Country of Residence, Gender and the Quality of Life in Australian and Taiwanese Midlife Residents

A growing global aging population is presenting more opportunities for health professionals to interact with other cultures. The specific aims of this study were to: (1) compare the quality of life of midlife men and women in Australian and Taiwan; and (2) to explore the impact of country of residence and gender on quality of life. A cross-sectional survey was conducted using census data and a probability proportional sampling (PPS) strategy on a general population of men and women aged 40–59 years-old who live permanently in Taiwan and Australia. The sample consisted of 278 Australians and 398 Taiwanese men and women. Analysis showed that country of residence does have an impact on quality of life with significant differences seen between midlife Australian and Taiwanese men and women (F 4, 666 = 59.31, p < 0.001). The results suggest that midlife Australian men and women have a better quality of life than midlife Taiwanese men and women. The mean score for the four domains of quality of life by gender indicated that midlife women consider that they have a better quality of life than midlife men in both Australia and Taiwan. Midlife Australian men in this study reported they are more dissatisfied with their sleep and rest (χ ² = 10.57, df = 4, p = 0.03) and more dissatisfied with their sexual activities (χ ² = 9.42, df = 4, p = 0.05) in contrast to midlife Australian women. This study has addressed and contributed to the assessment of multi-cultural quality of life research and has important implications for both health providers and policy makers of both countries.     

A distance measure of spatial pattern in a biological population

Summary Suppose thatn individuals locate independently and randomly on a segment of line of finite length (habitat). Let the theoretical and observed ranges of the sites of the individuals on the segment be μ _n-1 andr _n-1, respectively. Then, the degree of dispersion of the individual sites is measured by the ratio, T _n =n _n-1/μ _n-1, as follows: A random spatial pattern forI _r−1 =1 An aggregated spatial pattern for 0≤I _r <1 A uniform spatial pattern for (n+1)/(n−1)≥I _r >1. Another method was derived. Let the probability that an observed range is less thanr _n−1 beI _p , under the hypothesis of a Beta distribution. Then indicates A random spatial pattern forI _p =1/2 An aggregated spatial pattern forI _p <1/2 A uniform spatial pattern forI _p >1/2. The first index can be used for comparing populations having the same number of individuals, whereas the second one can be used for comparing populations with different numbers of individuals.     

The influence of urine from asymptotic laboratory populations on sexual maturation in prairie deermice

Summary Male and female prairie deermice housed singly from weaning (21 days) until 40 days of age had urine from one of the following sources applied daily to their nostrils: sexually mature laboratory population males or females, and sexually mature breeder males or females from our laboratory colony. Other males and females were treated with water. Records were obtained of the weights of the tests, seminal vesicles and bacula of males and the ovaries and uteri of females at 40 days of age. The major results of this study were as follow: Female urine from sexually mature and inhibited population or isolated mice stimulated the development of the male reproductive organs significantly more than water or male urine. Male urine applied to young males did not differentially affect the weights of their reproductive organs compared with water and thus showed no inhibition effects. The reproductive organs of females treated with male urine did not differ significantly in weight from those of females treated with female urine. Females treated with water developed significantly larger uteri than those treated with urine from sexually mature population females (P≤0.02), inhibited population females (P<0.001) and inhibited population males (P<0.007).     

The influence of pheromones produced by freely growing laboratory populations on the reproductive maturation of prairie deermice following prenatal and postnatal exposure

Summary Significantly more females reared on bedding soiled by different populations reproduced by 100 days of age than those reared on bedding soiled by the same populations (P<.1) or on clean bedding (P<.025) whereas the latter two groups did not differ significantly. Significantly greater percentages of females reproduced in both treatments maintained on soiled bedding than was true in the populations from which the bedding came. There were no significant differences between treatments in the weights of the reproductive organs (testes, seminal vesicles, ovaries, uteri) or in the numbers of corpora lutea or mature follicles in the ovaries of nulliparous females. The data suggest that if there were reproductively inhibiting pheromones influencing the population animals, they were altered or dissipated immediately after removal of the bedding from the population enclosures or that they were nonfunctional in the absence of the population animals. These data further suggest that the reproductive inhibition of population young is due to the presence of the populaton animals and that sociobiological factors within the populations act to prevent the reproductively stimulating influence of materials which may be present.     

Rapid evolution of larval development time during mass-rearing in the melon fly, Bactrocera cucurbitae

A quantitative genetic analysis of rapid evolution of a life history trait has been conducted on the first 24 generations of mass-rearing in the melon fly Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). The phenotypic variance of larval development time in each generation was divided into genetic and residual components. Mean and phenotypic coefficients of variation of larval development time decreased gradually as generations proceeded as a result of artificial selection for shorter larval period in the mass-rearing procedure. There was a trend that additive genetic coefficients of variation in larval development time decreased with generations. These changes are entirely attributed to genetic responses to laboratory selection under the mass-rearing environment because the population was maintained at a very large size so as to exclude random genetic drift and inbreeding depression, which would be other factors responsible for the observed genetic changes. The residual coefficients of variation in larval development time did not change with generations. Realized heritability of larval development time was low. The heritabilities for larval development time estimated from parent–offspring regression at generations 60 and 70, when the evolutionary plateau was asymptotically reached, were not significantly larger than 0. Received: April 22, 1999 / Accepted: September 20, 1999     

Life Satisfaction of Older Adults in Hong Kong: The Role of Social Support from Grandchildren

This study explores the relationship between the life satisfaction of older adults and the social support from grandchildren in Hong Kong. Two hundred and fifteen older people (from the ages of 64 to 101, mean age 79.3), whose youngest grandchild was aged 12 or older, were recruited from elderly service agencies to participate in the study. Face-to-face interviews were conducted by trained interviewers using a standardized questionnaire, which included the Life Satisfaction Scale for Chinese, the Lubben Social Network Scale, the Chinese Tradition Scale, grandchildren social support measures, self-rated health, self-rated financial adequacy, and demographic variables. Hierarchical regression showed that the life satisfaction of older adults benefitted significantly from the social support from grandchildren (R ² change = .05, F _change = 7.15, p < .001); while controlling demographic characteristics, general social support, attitude towards Chinese tradition, self-rated health, and self-rated financial adequacy. The total explained variance was 51%. Emotional support and appraisal support from grandchildren were identified as significant contributing factors. The policy and practice implications for active aging policies are discussed in a Chinese context.     

A genetic perspective on mating systems and sex ratios of parasitoid wasps

Parasitoid sex ratios are influenced by mating systems, whether complete inbreeding, partial inbreeding, complete inbreeding avoidance, or production of all-male broods by unmated females. Population genetic theory demonstrates that inbreeding is possible in haplodiploids because the purging of deleterious and lethal mutations through haploid males reduces inbreeding depression. However, this purging does not act quickly for deleterious mutations or female-limited traits (e.g., fecundity, host searching, sex ratio). The relationship between sex ratio, inbreeding, and inbreeding depression has not been explored in depth in parasitoids. The gregarious egg parasitoid, Trichogramma pretiosum Riley, collected from Riverside, CA (USA) produced a female-biased sex ratio of 0.24 (proportion of males). Six generations of sibling mating in the laboratory uncovered considerable inbreeding depression (∼ 20%) in fecundity and sex ratio. A population genetic study (based upon allozymes) showed the population was inbred (F _it = 0.246), which corresponds to 56.6% sib-mating. However, average relatedness among females emerging from the same host egg was only 0.646, which is less than expected (0.75) if ovipositing females mate randomly. This lower relatedness could arise from inbreeding avoidance, multiple mating by females, or superparasitism. A review of the literature in general shows relatively low inbreeding depression in haplodiploid species, but indicates that inbreeding depression can be as high as that found in Drosophila. Finally, mating systems and inbreeding depression are thought to evolve in concert (in plants), but similar dynamic models of the joint evolution of sex ratio, mating systems, and inbreeding depression have not been developed for parasitoid wasps. Received: November 13, 1998 /Accepted: January 8, 1999     

Binomial sampling plans for estimatingBemisia tabaci populations in cantaloupes

Early season infestations of the sweet potato whitefly,Bemisia tabaci (Gennadius), on cantaloupes,Cucumis melo L., were determined by counts of the number of adults per leaf in fields near Yuma, Arizona. We used these data to develop binomial sampling plans based on the relationship between mean densities of whiteflies per leaf,m, and proportion of leaves infested with more thanI whiteflies,P _I, according to the empirical model lnm=a′+b′ ln[−ln(1−P _I)]. The models were developed for the presence-absence approach (I=0) and for a cutoff value of three whiteflies per leaf (I=3). Four independent data sets were used to evaluate the models. Both methods yielded reliable predictions at low infestation levels, but some of the higherm values were overestimated. As the tentative economic threshold forB. tabaci is three adults per leaf, which corresponds to lowP _I values, results of the binomial sampling were satisfactory for pest management purposes.     

Convergent Validity and Test–Retest Reliability of the Authentic Happiness Inventory in Working Adults

This study aimed to test the convergent validity and test–retest reliability of a measure of happiness questionnaire; the authentic happiness inventory questionnaire (AHI), with a convenience sample of working adults (n = 30). Participants completed the AHI on two consecutive days. On the second day, participants also completed the Satisfaction with Life Scale (SWLS) and the positive and negative affect scale (PANAS). Internal consistency was determined using Cronbach alpha coefficients, test–retest reliability using a one-way intraclass correlation coefficient (ICC) model, and convergent validity using Pearson product-moment correlations. A further sample of working adults (n = 192) was included to conduct an exploratory factor analysis using principal component analysis (total n = 222). High internal consistency and overall test–retest reliability for the AHI was found (Cronbach alpha = .92 and ICC = .92, p < .001). There was a strong positive correlation between AHI and SWLS (r = .76, p < .005) and AHI and PANAS positive (r = .82, p < .005). There was a medium negative correlation between AHI and PANAS (r = .48, p < .005). Principal components analysis revealed the presence of five components with eigenvalues exceeding one, with one factor explaining 36.1 % of the variance. Findings confirmed the convergent validity and test retest reliability of the Authentic Happiness Inventory in working adults.

     

International Well-being Index: The Austrian Version

The International Well-being Index (IWI) measures both personal and national well-being. It comprises two subscales: the Personal Well-being Index (PWI) and the National Well-being Index (NWI). The aim of this paper is to test the psychometric properties (validity and reliability) of the translated scale in Austria. Convergent validity is assessed using the Scales of Psychological Well-Being, the Satisfaction with Life Scale and the Positive and Negative Affect Scale. In addition, a Visual–Analog Scales capturing “satisfaction with life as a whole” was applied. The participants were 581 students of the Medical University Innsbruck (female: 47.7%; age: 23.2 ± 3.7). Internal consistency (Cronbach’s α) of the IWI was for both scales > .70 (PWI: .85; NWI: .83). The exploratory factor analysis of the IWI identified a 2-factor-structure identical with the two scales of the IWI explaining 54.2% of the variance. The convergent validity hypotheses were confirmed, construct validity was partly confirmed for the PWI being a deconstruction of a first factor called “satisfaction with life” (38.1% explained variance). Happy participants scored higher on the PWI (84.3 ± 7.9 vs. 68.7 ± 13.7; p < .001) and NWI (64.3 ±  15.8 vs. 57.9 ±  15.1; p < .001) scores than unhappy participants. It is concluded that the Austrian version of the IWI is a reliable and valid instrument to assess personal and national well-being. Further studies including a representative sample should be carried out on a recurring basis to use the IWI as an indicator for social science research in Austria.     

On the mathematical basis of the variance-mean power relationship

The mathematical basis of a widely-known variance-mean power relationship of ecological populations was examined. It is shown that the log variance (S ²)—log mean, (m) plot is virtually delimited by two lines logS ²=logn+2 logm and logS ²=logm, thus increasing the chance that a linear regression line can be successfully fitted, without a profoundly behavioural background. This makes difficult the task of interpreting a successful fit of the power law regression and its parameterb in a biologically meaningful manner. In comparison with the power law regression, Iwao'sm ^*-m regression is structurally less constrained, i.e. has a wider spatial region in which data points can scatter. This suggests that a comparison between the two methods in terms of how good a fit is achieved for a particular data set is largely meaningless, since the power law regression may inherently produce a better fit due to its constrained spatial entity. Furthermore, it could be argued that a successful fit in Iwao's method, when found, is less taxed with mathematical arterfacts and perhaps more clearly linked to some biological mechanisms underlying spatial dispersion of populations.     

Construct and Criterion Validity of a Norwegian Instrument for Health Related Quality of Life Among Elderly Women Living at Home

Purpose of the study: The aim of the current study is to validate an instrument consisting of five items and first used in the Nord-Trondelag Health Survey (HUNT-5), as a measure of health related quality of life (QOL) in a population of elderly women living at home. Design and methods: A random sample of 307 women aged 75 years and over (mean 80.8 years, response rate 74.5%) and living at home were interviewed using the HUNT-5 instrument, the 20-question version of the General Health Questionnaire (GHQ-20) and the respondents’ records of their health status and functional ability. Results: No significant relationships were found between age and the sumscores of GHQ-20 and HUNT-5. Factor analysis indicated that HUNT-5 is primarily unidimensional. The Cronbach α for HUNT-5 was 0.79 and that for GHQ-20 was 0.87. The correlation between the HUNT-5 and the GHQ-20 sumscores was 0.75 (p < 0.001). There were significant correlations between some of the health and function items and the two QOL instruments (ranging from 0.14 to 0.68). Implications: This evaluation supports the psychometric validity of HUNT-5 for elderly women living at home. It is important to take into consideration the women’s own experience of their health and functional ability in planning therapy and in obtaining the best possible QOL for them.     

Safe drinking water and satisfaction with environmental quality of life in some oil and gas industry impacted cities of Nigeria

The availability and safety of drinking water and the environmental quality of life was investigated in five cities located in an oil-producing area of Nigeria using questionnaire-based scales, discussion and laboratory tests. Polythene-packaged sachet water and commercial and non-commercial private boreholes largely met the drinking water requirement of the cities. Consumption of sachet water was high (14.0–20.0 points vs. 25.0 points) but regression analysis indicated strong negative relationships with income group (β = −0.75, P < 0.005) and educational level (β = −0.77, P < 0.005) of respondents (658). Private borehole water was prevalent (18.7–19.9 vs. 20.0) while public water supplies were almost non-existent (4.8–5.6 vs. 20.0) in the cities. Vulnerability to contamination in all water sources was indicated following unacceptable counts of total and faecal coliform bacteria in 10–62.5 and 3–25% of samples, respectfully. Respondents were not satisfied with environmental quality of life indicated by the quality of housing, school, health services, refuse disposal, recreation, streetlight, transport and police (3.43–4.01 vs. 10). It is concluded that modernization and industrialization due to the oil and gas industries, tended to increase individualization to the negligence of common services as evidenced by the preponderance of private boreholes and sachet water.     

Spatial pattern indices based on distances between individuals on a line-segment with finite length

Summary Let us consider a strip-wise habitat of line-segment, like a corridor, to simplify the subject mathematically, and assume that the length of the habitat is γ and there aren individuals. Here, we assume that the spatial pattern of the individuals is random if then distances from the left end of the habitat to each individual follow a uniform distribution on the strip. Under such an assumption, the variance of the distances between any two neighbors is represented by the formulanθ ²(n+1)⁻²(n+2)⁻¹ and the variance betweenn+1 distances betweenn individuals from the left end to the right end to the strip, is represented by the formulanθ ²(n+1)⁻²(n+2)⁻¹. These two kinds of variances can be used for determining (1) the spatial pattern of a population on the strip and (2) the spatial structure within the population, by comparison with the variances calculated from the data. Two examples cited from the literature, a cattle population on a pasture and an aphid population on a sycamore leaf, are presented.