First-generation Females Research Articles

Emergence of college students’ John Henryism during schoolwork: an exploratory study

John Henryism (JH), named after the American folk hero John Henry, is a construct characterised by a behavioural predisposition for high-effort coping with psychosocial stressors. While it has been rigorously studied in the health sciences, little empirical research has focused on how JH emerges within educational contexts, specifically during schoolwork. This exploratory study investigated factors related to JH—race/ethnicity, gender, first-generation college student status, and high-effort coping—on school-based cognitive and emotional engagement. Results revealed that high JH scores predicted positive cognitive and emotional momentary engagement, particularly for racial/ethnic minorities and first-generation college students. Furthermore, in comparing our subsample of first-generation females with our overall sample of female students, we learned that JH had a greater positive influence on first-generation females’ momentary engagement than on that of the overall sample of female students. Findings suggest that historically marginalised groups may regularly rely on JH to cope with systemic inequality in school activities.

Fish-breeding, biological and production characteristics of first- and second-generation carp hybrids of breeding

A comparative analysis of the fish-breeding and production characteristics of first- and second-generation carp hybrids obtained from crossing local mongrel females with males of the intra-breed type of the Moscow scaly pair carp was carried out. As a result of parallel cultivation of five variants of crossing carp to their puberty with further verification of breeding value for offspring, a promising hybrid (♀Me × M♂) was selected, with which breeding work was carried out for two generations. A comparison of the fish-breeding biological and production characteristics of twogeneration carp hybrids revealed the best indicators for all the parameters studied in the first generation, which, apparently, is associated with the phenomenon of heterosis. Producers of carp hybrids for three years of work with them (4–6-yearolds) had a more pronounced fertility in the production of oocytes in first-generation females, both in terms of working and relative fertility. As for males, there were no significant differences in the one-time volume of ejaculate, concentration and degree of sperm motility in hybrid individuals of two generations of carp in studies. The exterior indicators of carp hybrids according to the high-spin index in the first generation exceeded the same indicator in the second generation. The additional calculation carried out for the variation of the analyzed indicators revealed slightly lower values of the coefficient of variation in the second generation among different age groups of carp. This situation of the emerging tendency to decrease the spread of the analyzed indicators in relation to their average values can be explained by the effect of stabilizing selection in the second generation of the hybrid carp. According to the results of the study of the fish-breeding, biological and productive characteristics of two generations of carp hybrids, a return crossing with an improver breed (Moscow scaly) was performed.

Gender, Generation, and Multiracial Identification in the United States.

Multiracial self-identification is frequently portrayed as a disproportionately female tendency, but previous research has not probed the conditions under which this relationship might occur. Using the 2015 Pew Survey of Multiracial Adults, we offer a more comprehensive analysis that considers gender differences at two distinct stages: reporting multiple races in one's ancestry and selecting multiple races to describe oneself. We also examine self-identification patterns by the generational locus of multiracial ancestry. We find that females are more likely to be aware of multiracial ancestry overall, but only first-generation females are more likely than their male counterparts to self-identify as multiracial. Finally, we explore the role of racial ancestry combination, finding that multiracial awareness and self-identification are likely gendered differently for different segments of the mixed-race population. This offers a more nuanced picture of how gender interacts with other social processes to shape racial identification in the United States.

Exploring Factors that Predict STEM Persistence at a Large, Public Research University

The present study explores demographics, pre-college characteristics and multi-year (2003-2013) tracking of a census of 53,077 students who initially declared a STEM major upon entering a research university in Texas and seeks to predict graduation with a STEM and non-STEM degree. Guided by QuantCrit theory, we use multilevel models to determine factors that predicted persistence in any major and factors that predicted persistence in STEM, as well as use marginal effects to explore the intersection of ethnicity, sex, and first-generation status. Results highlight the disparity that exist amongst Black students and their White counterparts with regards to persistence in any major. We also highlight the gap between first-generation White and Black first-generation females and their Asian and International counterparts with regards to persistence in STEM. Implications for future research and practitioners suggest further attention needs to be paid to Black first-generation students.

Genomic evidence of recent hybridization between sea turtles at Abrolhos Archipelago and its association to low reproductive output

Hybridization between sea turtle species occurs with particularly high frequency at two adjacent nesting areas in northeastern Brazil. To understand the outcomes of hybridization and their consequences for sea turtle conservation, we need to evaluate the extent of hybridization occurrence and possible deleterious effects in the hybrid progeny. Thus, we investigated the hypothesis of the existence of a new hybrid spot offshore of Brazil’s northeastern coast. The Abrolhos Archipelago is surrounded by the largest and richest coral reefs in the South Atlantic and is known to be a nesting site for loggerhead turtles (Carettacaretta). In this study, we performed a multidisciplinary investigation into levels of hybridization in sea turtles and their reproductive output in the Abrolhos beaches. Genetic data from mitochondrial DNA (mtDNA) and six autosomal markers showed that there are first-generation hybrid females nesting in Abrolhos, resulting from crossings between hawksbill males (Eretmochelysimbricata) and loggerhead females, and backcrossed hatchlings from both parental species. The type and extent of hybridization were characterized using genomic data obtained with the 3RAD method, which confirmed backcrossing between F1 hybrids and loggerhead turtles. The reproductive output data of Abrolhos nests suggests a disadvantage of hybrids when compared to loggerheads. For the first time, we have shown the association between hybridization and low reproductive success, which may represent a threat to sea turtle conservation.

What determines the occurrence of fertilized females in hibernating populations of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) in Central Europe?

The current climate warming is associated with the development of a second generation in populations of species such as Pyrrhocoris apterus (L.) (Heteroptera: Pyrrhocoridae), which, in Central Europe, were univoltine in the 1980s. Females of the first generation that develop in spring either enter diapause immediately following the adult moult or after a period of oviposition that gives rise to a second generation. In 2005-2010, in overwintering populations, 3 ± 0.6% of females were fertilized. We explored the possibility that the females that overwintered in a fertilized state were those that had oviposited in the previous season. To test this hypothesis, we reared females of the first generation that moulted to the adult stage in June-August under natural conditions. For these females, we recorded oviposition, mortality and overwintering in the fertilized state. In 2004-2007, the majority (78%) of the first-generation females that oviposited in summer also died before winter and the rest entered dormancy and overwintered. Most of the overwintering females that had laid eggs before overwintering were fertilized. However, the majority (63%) of females that overwintered in the fertilized state had not laid eggs in the previous season; they only copulated and stored the sperm until the next spring. The presence of fertilized females in a hibernating population thus indicates pre-winter sexual activity but not the percentage of first-generation females that oviposit before overwintering.

Steinernema bertusi n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from South Africa

Summary Two isolates of Steinernema bertusi n. sp. were separately recovered from Tito, Mpumalanga, and Port Edward, Kwa Zulu Natal, South Africa. In this paper, we describe the isolates as a new entomopathogenic nematode (EPN) species using molecular and morphological methodologies. The new species belongs to the cameroonense-clade, which consists of nematodes only isolated from the African continent. Steinernema bertusi n. sp. is characterised by having the longest infective juvenile (IJ) for this clade at 716 (628-814) μm. The IJ is further characterised by a body diam. of 32 (28-36) μm and the pattern for the arrangement of the lateral ridges from head to tail is 2, 4, 5, 4, 2. The first-generation male spicule and gubernaculum length is 82 (72-88) μm and 63 (54-72) μm, respectively. Only 25% of the second-generation males possess a mucron. The first-generation females of S. bertusi n. sp. have a slightly protruding vulva, with double-flapped epiptygmata and a mucron at the posterior end. The new EPN species is most closely related to S. sacchari and is the sixth species to be included in the cameroonense-clade.

Effect of some nanoparticles on the stages biology of the southern cowpea beetle Callosobruchus maculatus (Fab.) (Coleoptera:Bruchidae)

Nano particle of Zinc oxide size (5nm) and (100nm) and silver nano Particle (100 nm) were used in This study at concentrations (100, 250, 500, 750 and 1000) ppm to know their effect on some biological aspects of the southern cowpea beetle Callosobruchus maculatus (Fab.) through treating the food of these insects (chick pea seeds) by these nanoparticles. The study proved that the above Particles had a significant effect on the parentage of eggs hatching as it reached 49.4% compared to 86.9% of control Also, the some treatment led to high at 1000 ppm concentration mortality percentage 98%. Moreover, the treatment had an effect on the pupa stage and on the period of insect development, which was elongated significantly in the treatments of the zinc oxide size (100 nm). The maximum period was 40.60 days at the concentration of 1000 ppm Which differed significantly from its comparative coefficient. The productivity of insect decreased significantly to 16.6%in zinc oxide nano Particle size (5 nm) clearly. This study showed that the treatments effected the vitality of the first-generation females as the percentage of egg hatching decreased to 50% more than that egg retention was observed on these females which reached to 50% at treatment of zinc oxide size (5 nanometer).

Seasonal occurrence and development of three closely related Oligonychus species (Acari: Tetranychidae) and their associated natural enemies on fagaceous trees.

We compared the life cycles and diapause attributes among three closely related spider mites, Oligonychus castaneae on Castanea crenata, and O. gotohi and O. amiensis on Lithocarpus edulis. The lower thermal thresholds from egg to egg were 10.5, 8.5 and 8.9°C, respectively, and the thermal constants were 177.8, 229.5 and 232.5 degree-days, respectively. The cumulative hatching rates of diapause eggs of O. castaneae and O. gotohi increased as the season progressed in and after early-to-mid January, which indicates diapause termination. In contrast, O. amiensis showed higher hatching rates in December and January, but hatchability gradually decreased in and after February because some of the eggs died from the cold. Oligonychus castaneae and O. gotohi females produced diapause eggs in response to the short photoperiod in late September to early October and in early-to-late October, respectively, which corresponded to the times predicted by the critical photoperiods (at 15°C) of 12h 15min and 11h 15min for the respective species. Oligonychus castaneae showed at least a single population peak over the 3-year observation period, but the time of peak population varied from mid-July to mid-September. The population of O. gotohi was higher between November and May when diapause eggs were present on host plants in early winter and the first-generation females laid eggs on leaves in spring. The population of O. amiensis, which is a non-diapause species, was only high between September and December, because eggs were laid on leaves in autumn to winter and then gradually disappeared and/or died during winter. Natural enemies were observed as the number of spider mites declined, and the density suppression effect by natural enemies was confirmed in the field.

The first report of Xenorhabdus indica from Steinernema pakistanense: co-phylogenetic study suggests co-speciation between X. indica and its steinernematid nematodes.

During a survey in agricultural fields of the sub-humid region of Meerut district, India, two strains of entomopathogenic nematodes, labelled CS31 and CS32, were isolated using the Galleria baiting technique. Based on morphological and morphometric studies, and molecular data, the nematodes were identified as Steinernema pakistanense, making this finding the first report of this species from India. For the first time, we performed a molecular and biochemical characterization of the bacterial symbiont of S. pakistanense. Furthermore, a co-phylogenetic analysis of the bacteria from the monophyletic clade containing a symbiont of S. pakistanense, together with their nematode hosts, was conducted, to test the degree of nematode-bacteria co-speciation. Both isolates were also tested in a laboratory assay for pathogenicity against two major pests, Helicoverpa armigera and Spodoptera litura. The morphology of the Indian isolates corresponds mainly to the original description, with the only difference being the absence of a mucron in first-generation females and missing epiptygmata in the second generation. The sequences of bacterial recA and gyrB genes have shown that the symbiont of S. pakistanense is closely related to Xenorhabdus indica, which is associated with some other nematodes from the 'bicornutum' group. Co-phylogenetic analysis has shown a remarkable congruence between the nematode and bacterial phylogenies, suggesting that, in some lineages within the Steinernema / Xenorhabdus complex, the nematodes and bacteria have undergone co-speciation. In the virulence assay, both strains caused a 100% mortality of both tested insects after 48 h, even at the lowest doses of 25 infective juveniles per insect, suggesting that S. pakistanense could be considered for use in the biocontrol of these organisms in India.

Reproductive Plasticity of an Invasive Insect Pest, Rice Water Weevil (Coleoptera: Curculionidae)

Reproductive plasticity is a key determinant of species invasiveness. However, there are a limited number of studies addressing this issue in exotic insects. The rice water weevil Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), which is native to North America, is one of the most invasive insect pests in east Asia. In this study, we investigated the reproductive status of first-generation females (progeny of overwintered weevils) from five geographic regions in southern and northern China in the field, and reproductive status and ovipositional features of females provided with suitable host plants in the laboratory after collection. Under field conditions, a proportion of females oviposited, while the rest remained in diapause from all three southern regions investigated, but reproductive development did not take place in females from the two northern regions, where the weevil produces only one generation per year. However, when fed host plants in the laboratory, females from all regions laid eggs. They typically had a very short ovipositional period (3-6 d on average on rice at a temperature of 27°C), laid a low number of eggs, and did not die soon after oviposition; this was different from common reproductive females. We concluded that first-generation L. oryzophilus females, which largely enter diapause after emergence, are highly plastic in their reproductive performance and are ready to reproduce under favorable conditions. Our results indicate the significance of their reproductive plasticity for geographic spread and population development.

Steinernema pwaniensis n. sp., a new entomopathogenic nematode (Nematoda: Steinernematidae) from Tanzania.

A new species of entomopathogenic nematode, Steinernema pwaniensis n. sp., belonging to the glaseri group, is described from Tanzania. The infective juveniles of S. pwaniensis n. sp. are characterized by a body length of 978μm (808-1131), distance from anterior end to excretory pore of 86μm (80-95) and a tail length of 87μm (75-95). The ratios a, c and E% of S. pwaniensis n. sp. are substantially lower than those of all other African 'glaseri' group members. The first-generation males of S. pwaniensis n. sp. can be distinguished by a large spicule length of 92μm (80-97) and by the absence of the caudal mucron, while second-generation males possess a short spine-like mucron. First-generation females have a peg-like tail tip bearing three spine-like projections. Second-generation females can be recognized by a slightly protruding vulva and well-developed post-anal swelling. The new species is further characterized by sequences of the internal transcribed spacer (ITS) and partial 28S regions of the ribosomal DNA. Phylogenetic analyses show that S. pwaniensis n. sp. forms a strongly supported monophyletic clade with two other East African species, S. ethiopiense and S. karii.

Steinernema beitlechemi n. sp., a new entomopathogenic nematode (Nematoda: Steinernematidae) from South Africa

Steinernema beitlechemin. sp. is a new species of entomopathogenic nematode isolated from soil samples collected in Bethlehem, Free State province, South Africa. The infective juveniles ofS. beitlechemin. sp. are characterised by a body length of 696 (606-768) μm, position of nerve ring of 96 (86-105) μm from the head and lateral fields with six ridges (i.e., seven lines) in mid-body. First-generation males ofS. beitlechemin. sp. can be distinguished by a spicule length of 93 (88-100) μm and 12 pairs of genital papillae. First-generation females have a moderately protruding vulva and a rounded tail tip bearing one spine-like projection. The new species is further characterised by sequences of the ITS and partial 28S regions of the ribosomal DNA. Phylogenetic analyses showS. beitlechemin. sp. as a member of a strongly supported monophyletic clade with three other African species:S. sacchari,S. cameroonenseandS. nyetense.

Steinernema jeffreyense n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from South Africa.

During a non-targeted survey for entomopathogenic nematodes in South Africa, a new species of Steinernema was isolated from a soil sample collected from underneath a guava tree, close to the shore at Jeffrey's Bay. The nematode was isolated by means of the insect-baiting technique using last-instar larvae of Galleria mellonella. It is described herein as Steinernema jeffreyense n. sp. The nematode can be separated from other described, closely related species in terms of the morphological and morphometric characteristics of the different life stages, and in terms of the characterization and phylogeny of DNA sequences of the internal transcribed spacer (ITS) rDNA of the 18S gene, and of the D2D3 region of the 28S rDNA gene. The new species is placed molecularly in the arenarium-glaseri-karii-longicaudatum group characterized by the following morphological characters: infective third-stage juvenile with a body length of 926 (784-1043)μm, distance from head to excretory pore of 87 (78-107)μm, tail length of 81 (50-96)μm, with an E% of 109 (86-169), and eight evenly spaced ridges (i.e. nine lines) in the middle of the body. First-generation males have a spicule length of 88 (79-95)μm and gubernaculum length of 57 (51-61)μm. Male mucron is absent in both generations. First-generation females have an asymmetrical protuberance and a short, double-flapped epiptygmata, with both flaps directed to the front. The tail of the first-generation female is shorter than the anal body width, with a mucron on the dorsal tail tip, with D%=78 (59-99). Cross-hybridization with S. khoisanae, S. tophus and S. innovationi showed the new species to isolate reproductively from the others. The analyses of ITS rDNA and D2D3 sequence of the 18S and 28S rDNA genes support the studied nematode isolate to be a valid new species belonging to the 'glaseri' group (Clade V).

The associations between sex, immigrant status, immigrant concentration and intimate partner violence: Evidence from the Canadian General Social Survey

Intimate partner violence (IPV) is an important public health concern, yet little is known about the combined effects of individual- and neighbourhood-level characteristics on IPV among immigrants. The aim of this study is to examine: (1) the association between immigrant status and IPV victimisation and whether sex modifies this association, and (2) the association between the neighbourhood concentration of immigrants and IPV victimisation, and whether immigrant status modifies this association. Our sample of 10,964 males and females comes from the 2009 Canadian General Social Survey. After controlling for covariates, immigrant status was not associated with IPV, and sex significantly modified the association between immigrant status and financial and physical/sexual IPV. Compared to males, second-generation females were less likely to report financial IPV and first-generation females were more likely to report physical/sexual IPV. Immigrant status modified the association between the neighbourhood concentration of immigrants and emotional and physical/sexual IPV. Compared to third-generation males, first-generation males living in neighbourhoods with a higher concentration of immigrants were more likely to report emotional IPV, whereas second-generation males in these neighbourhoods were less likely to report physical/sexual IPV. Interventions to reduce IPV should pay equal attention to individual- and neighbourhood-level influences.

Evaluation of Spanish Arundo scale Rhizaspidiotus donacis (Hemiptera; Diaspididae) survival and fecundity on three new world genotypes of Arundo donax (Poaceae; Arundinoideae)

A pre-release evaluation of survival and fecundity of the arundo scale, Rhizaspidiotus donacis, was conducted on three invasive genotypes of the riparian weed, Arundo donax. The three A. donax genotypes were collected from Laredo, Austin and Balmorhea, TX, which represented the majority of the genotypic diversity found in Texas watersheds. Although R. donacis developed on all three genotypes of the plant, the Austin A. donax genotype, followed by the Laredo genotype, were the most suitable in terms of the size of first-generation immature and adult scale populations that developed after crawler release. Both the Laredo and Austin genotypes of A. donax are likely to be of Spanish origin and are close genetic matches with scale's original host plant genotype in Alicante, Spain. In comparison, survival was lowest on the phylogenetically distant genotype of A. donax from Balmorhea, TX. Although the population size of settled, immature second-generation scales varied in a manner similar to that of the first generation, the fecundity of isolated first-generation females was not significantly different across the three plant genotypes, suggesting that R. donacis is not a genotype specialist in terms of nutrient assimilation for reproduction. Rather, differences in genotype suitability affect rates of success of crawler settling. These results indicate that selection of scale genotype from the native range may have a moderate influence on the success of R. donacis and ultimately the biological control programme.

Seasonal variation in the effect of climate on the biology of Rhipicephalus sanguineus in southern Europe

Rhipicephalus sanguineus is the most widespread tick in the world and a vector of many pathogens infecting dogs and humans. To date, there have been no investigations on the biology of R. sanguineus under natural Mediterranean climatic conditions. The biology of R. sanguineus was studied under laboratory and natural climatic conditions in southern Italy. Several biological parameters were compared in different seasons, and their correlation with climatic data was assessed. The life cycle of R. sanguineus lasted for a mean of 101·4 and 116·2 days under laboratory and environmental conditions respectively. Reproductive parameters of wild-collected females kept in the environment in May were significantly different from first-generation females maintained in September-October, and the correlation between reproductive parameters and climate data varied according to season. These results indicate that the Mediterranean climate affects the biology of R. sanguineus, which compensates its losses during the initial phases of its cycle in spring with high feeding and moulting rates of larvae and nymphs during summer as well as with high egg production during autumn. These results advance our knowledge of the biology of R. sanguineus and will be useful for the understanding of the eco-epidemiology of tick-borne diseases that this tick transmits.

Delayed Fatherhood in Mice Decreases Reproductive Fitness and Longevity of Offspring1

This study aims to analyze, in mice, the long-term effects of delayed fatherhood on reproductive fitness and longevity of offspring. Hybrid parental-generation (F(0)) males, at the age of 12, 70, 100, and 120 wk, were individually housed with a randomly selected 12-wk-old hybrid female. The reproductive fitness of first-generation (F(1)) females was tested from the age of 25 wk until the end of their reproductive life. In F(1) males, the testing period ranged from the age of 52 wk until death. Breeding F(1) females from the 120-wk group displayed interbirth intervals longer than females from the 12-, 70-, and 100-wk groups. Furthermore, F(2) pups begotten by F(1) studs exhibited weaning weights lower than pups from the 12- and 70-wk groups. Offspring from the 120-wk group exhibited shorter survival times associated with lower incidence of tumorigenesis and higher loss of body weight when approaching death when compared to F(1) offspring from younger age-groups. The results indicate that advanced paternal age at conception has negative long-term effects on reproductive fitness and longevity of offspring in the mouse model.

Roles of gender, race, and SES in the college choice process among first-generation and nonfirst-generation students.

The authors examined students’ reports of their college choice process to understand the influence of a set of psychological, personal, and institutional factors. The authors also examined potential moderating influences of generational status, gender, race, and SES on our variables of interest. A diverse sample of college freshmen (N 1,339), including 42% who were the first in their families to attend college, responded to a self-reporting, Web-based survey. Findings indicate that psychosocial factors and academic quality of the college were most influential for first-generation students as compared to their nonfirst-generation peers in the college choice process. However, gender, race, and SES moderated these influences in complex ways. For example, females rated the psychological variables higher than males; Asian American and African American first-generation students rated higher than their parents’ preferences for which college to attend as compared to nonfirst-generation peers. First-generation females, African American in particular, considered academic quality more important than other groups. Our findings should be of value to counselors and other personnel who facilitate students’ college choice process as well as college recruitment, retention, and diversity enhancement programs.

Reproductive Potential of Overwintering, F<SUB>1</SUB>, and F<SUB>2</SUB> Female Boll Weevils (Coleoptera: Curculionidae) in the Lower Rio Grande Valley of Texas

The feeding and oviposition activity of overwintering boll weevils, Anthonomus grandis grandis (Boheman), and seasonal fluctuations in development, survival, and reproduction of progeny of overwintering and first- and second-generation boll weevil females were determined in the laboratory at 27 degrees C, 65% RH, and a photoperiod of 12:12 (L:D) h. During the cotton-free period in the Lower Rio Grande Valley, female boll weevils without access to cotton resorb their unlaid eggs and enter reproductive diapause. However, when they were provided daily with greenhouse-grown cotton squares, commencement of oviposition began after 7, 15, or 20 d, depending on when they were captured. Females captured later in the winter fed longer before laying eggs than those captured in the early fall, suggesting that it may take females longer to terminate diapause the longer they have been dormant. The rate of feeding by females was significantly less during the winter months, and this may have affected the rate of diet-mediated termination of dormancy. Females of the first and second generations after the overwintering generation produced a significantly higher percentage of progeny surviving to adulthood and a higher proportion of these progeny were females. Offspring development time from overwintering female parents was significantly longer than that from first and second generations under the same laboratory conditions. The total number of lifetime eggs produced by females of the second generation during the cotton-growing season were approximately 9.9-fold higher than for overwintering females and 1.5-fold higher than for first-generation females. Life table calculations indicated that the population of second-generation boll weevils increased an average of 1.5-fold higher each generation than for females of the first generation and 22.6-fold higher than for overwintering females. Our data showed variation in boll weevil survival, development, and reproductive potential among the overwintering and first- and second-generation females, suggesting inherent seasonal fluctuations in these parameters.