De novo genome assembly and comparative genomics for the colonial ascidian Botrylloides violaceus.

Ascidians have the potential to reveal fundamental biological insights related to coloniality, regeneration, immune function, and the evolution of these traits. This study implements a hybrid assembly technique to produce a genome assembly and annotation for the botryllid ascidian, Botrylloides violaceus. A hybrid genome assembly was produced using Illumina, Inc. short and Oxford Nanopore Technologies long-read sequencing technologies. The resulting assembly is comprised of 831 contigs, has a total length of 121 Mbp, N50 of 1 Mbp, and a BUSCO score of 96.1%. Genome annotation identified 13 K protein-coding genes. Comparative genomic analysis with other tunicates reveals patterns of conservation and divergence within orthologous gene families even among closely related species. Characterization of the Wnt gene family, encoding signaling ligands involved in development and regeneration, reveals conserved patterns of subfamily presence and gene copy number among botryllids. This supports the use of genomic data from nonmodel organisms in the investigation of biological phenomena.

Sex Attractant Pheromones of Virgin Queens of Sympatric Slave-Making Ant Species in the Genus Polyergus, and their Possible Roles in Reproductive Isolation.

Species of the ant genus Polyergus are social parasites that steal brood from colonies of their hosts in the closely related genus Formica. Upon emergence as adults in a mixed population, host Formica workers carry out all the normal worker functions within the Polyergus colony, including foraging, feeding, grooming, and rearing brood of the parasitic Polyergus ants. Some unmated Polyergus gynes (queens) run in the raiding columns of their colonies and attract males by releasing a pheromone from their mandibular glands. There are two Polyergus species groups in North America: an eastern P. lucidus group and a western P. breviceps group. One species of each of these groups, P. lucidus Mayr and P. mexicanus Emery, are sympatric in Missouri. In this study, we characterized the sex pheromones of virgin queens of two species of the P. lucidus group (P. lucidus sensu stricto and P. sanwaldi) and one species of the P. breviceps group (P. mexicanus), and compared these with the previously identified sex pheromone of P. topoffi of the P. breviceps group. We then used sex pheromone blends reconstructed from synthesized components of the two groups to test their efficacy at reproductively isolating these species. We found that methyl 6-methylsalicylate is conserved as the major component of the pheromone blends for both Polyergus species groups; however, methyl (R)-3-ethyl-4-methylpentanoate is the species-specific minor component produced by P. lucidus group queens, and (R)-3-ethyl-4-methylpentan-1-ol is the crucial minor component for P. breviceps group queens. The optimal ratio of the major and minor components for P. lucidus group queens was about 100:1 salicylate to ester. In concurrent field trials in Missouri, males of P. lucidus sensu stricto and P. mexicanus (a member of the P. breviceps group) were attracted almost exclusively to their particular blends of sex pheromone components. To our knowledge, this is the first example of a possible sex-pheromone-based reproductive isolating mechanism in ants.

Attitudes Toward Divorce, Commitment, and Divorce Proneness in First Marriages and Remarriages.

A random multistate sample of married individuals (N = 1,931) was used to explore whether more positive attitudes toward divorce and weaker commitment to marriage may contribute to the greater instability of remarriages than first marriages. Remarried adults, whether or not they brought children from a previous union into the remarriage, reported marital quality (happiness and conflict) equal to those in first marriages. They also reported more positive attitudes toward divorce, which were associated with higher divorce proneness (i.e., thinking about and taking actions toward divorce). Marriage type interacted with marital quality to predict divorce proneness, such that the association between low marital quality and divorce proneness was stronger for remarried individuals than for those in first marriages. This suggests that remarried adults may be more likely than adults in first marriages to take steps toward divorce when experiencing marital distress, possibly reflecting a weaker commitment to marriage.

The Timing of Cohabitation and Engagement: Impact on First and Second Marriages.

Using a multi-state sample of marriages that took place in the 1990s, this study examined associations between premarital cohabitation history and marital quality in first (N = 437) and second marriages (N = 200), and marital instability in first marriages (intact N = 521, divorced N = 124). For first marriages, cohabiting with the spouse without first being engaged or married was associated with more negative interaction, higher self-reported divorce proneness, and a greater probability of divorce compared to cohabiting after engagement or marriage (with patterns in the same direction for marital positivity). In contrast, there was a general risk associated with premarital cohabitation for second marriages on self-reported indices of marital quality, with or without engagement when cohabitation began.

Differential use of premarital education in first and second marriages.

Although second marriages are more likely to end in divorce than first marriages, and thus represent an important target for intervention, there have been no detailed examinations of the use of premarital education in second marriages. Using random-digit dialing methods, 398 individuals currently in a second marriage and 1,342 individuals currently in a first marriage participated. Compared with those in first marriages, individuals in second marriages were significantly less likely to receive premarital education for their current marriage. This difference was fully mediated by differences between individuals in first and second marriages in pre-engagement cohabitation, education level, having children from a previous relationship, and being married by a religious leader. In both first and second marriages, those couples at most risk for subsequent marital distress and divorce were less likely to receive premarital education. Results suggest that more needs to be done to understand the barriers to the use of premarital education for second marriages.

Impact of parasite sympatry on the geographic mosaic of coevolution.

Slave-making ants are specialized social parasites that steal the young from colonies of their host species to augment their slave supply. The degree of parasite-host specialization has been shown to shape the trajectory along which parasites and hosts coevolve and is a prime contributor to the geographic mosaic of coevolution. However, virtually nothing is known about extrinsic influences on parasite-host dynamics, although the simple addition of a competing slave-maker may significantly alter selection pressures. Here we report the effect of two sympatric slave-makers on a single host. We measured temporal and spatial changes in colonies of the primary host Temnothorax curvispinosus that had been placed in field enclosures along with a single colony of either one or both species of the North American slave-making ants Protomognathus americanus and Temnothorax duloticus. Each slave-maker species alone had a negative impact on its hosts, although one slave-maker species more frequently decimated its host assemblage and then went extinct. Nevertheless, the combined effect in mixed-parasite enclosures was, surprisingly, greatly attenuated. Virulent slave-maker growth and prudent slave-maker decay in these shared enclosures, together with field data showing an inverse proportional relationship between the two slave-makers in natural populations, suggest that their checkered distribution is a consequence of direct asymmetrical antagonism between parasites. Thus, our results imply a tripartite coevolutionary arms race, whereby intraguild interactions among social parasites strongly affect the realized selection pressures on hosts and contribute to the geographic mosaic of coevolution.

Premarital education, marital quality, and marital stability: findings from a large, random household survey.

One of the limitations of experimental studies on the effectiveness of premarital education is the reliance on samples of mostly White, middle-class couples. In contrast, although survey methods allow only weak inferences about causal relations, representative surveys can yield important information about use and estimated effects across a diverse population. Using a large random survey of 4 middle American states, the authors found that participation in premarital education was associated with higher levels of satisfaction and commitment in marriage and lower levels of conflict-and also reduced odds of divorce. These estimated effects were robust across race, income (including among the poor), and education levels, which suggests that participation in premarital education is generally beneficial for a wide range of couples.

Recruitment of healthy participants for studies on risks for alcoholism: effectiveness of random digit dialling.

AIMS: To compare the effectiveness of two strategies for recruiting healthy research volunteers. METHODS: Demographic characteristics and recruitment costs of participants who completed a laboratory study examining risk factors for alcoholism recruited through random digit dialling (N = 11) and community advertisements (N = 102) were compared. RESULTS: Advertisement yielded a more representative sample [76% Caucasian, less well educated (M = 15.2 years, SEM = 0.2; P < 0.05), more equally divided by family history of alcoholism (43% FH- and 57% FH+), and lower in SES (M = 42.8, SEM = 1.3; P < 0.05)] and was more cost effective (72 dollars vs 2272 dollars per participant) than random digit dialling. CONCLUSIONS: Findings are relevant to alcohol researchers trying to determine the recruitment strategy that will yield the most representative sample at the lowest cost.

A diabetes prevention assessment tool for American Indians.

INTRODUCTION: American Indians have a disproportionately higher risk of developing type 2 diabetes. Few data are available about the perceptions of diabetes among American Indians, and no culturally appropriate tools are available for assessment of perceptions related to health and diabetes. METHODS: A diabetes prevention assessment tool was developed to measure perceptions of health and diabetes among American Indians. Predominant themes from qualitative interviews were used to develop the items for the tool. Data were collected at two autumn powwows, or intertribal dances, in Oklahoma. Reliability testing was performed using 185 surveys from American Indian adults not living on reservations. Principal axis factor analysis was performed to identify possible relationships among the items. RESULTS: Five themes, or factors, were found to categorize the perceptions of health: 1) lifestyles, 2) barriers to healthy lifestyles, 3) personal responsibility, 4) self-care behaviors, and 5) culturally defined well-being. Two factors classified the perceptions of diabetes: 1) a cognitive factor, related to personal experience, and 2) an affective factor, related to emotions. CONCLUSION: Our diabetes assessment tool identified factors that should be considered when developing health promotion and diabetes prevention programs for American Indians. A valid assessment tool for the American Indian population could provide valuable, formative data that would increase understanding of the culturally related obstacles to health promotion and diabetes prevention.

Patterns of continuing professional education in registered dietitians and dietetic technicians, registered.

This study compared the continuing professional education (CPE) activities of registered dietitians (RDs) with those of dietetic technicians, registered (DTRs). A descriptive research study was used with data from the baseline survey evaluating the Commission on Dietetic Registration's (CDR) Professional Development Portfolio. The survey was sent to 3,530 randomly selected RDs and DTRs; 1,429 surveys were returned (40.5% response rate), with 41% of RDs contacted responding and 32% of DTRs responding. Guidance used when selecting CPE activities and type of CPE activity selected were measured. DTRs sought more guidance than RDs when selecting CPE activities (P=.001). A significantly higher percentage of RDs than DTRs selected lectures, workshops, journal clubs, satellite courses, exhibits, professional leadership, professional reading, and poster sessions as CPE activities (P<.05). These findings will aid CPE providers in knowing which CPE activities are typically selected by both dietetics credential groups. DTRs may need guidance in selecting CPE activities.

The emergence of collective foraging in the arboreal Gnamptogenys menadensis (Hymenoptera: Formicidae).

Gnamptogenys menadensis is an arboreal nester that forages opportunistically almost exclusively on vegetation, sometimes recruiting others to participate in prey retrieval. The three-dimensional characteristics of vegetation suggest that functions describing recruitment decision thresholds or the pattern of recruitment in arboreal species may differ from those predicted by optimal foraging theory. To examine the effects of prey abundance and distance on the recruitment dynamics of G. menadensis, we baited nests with one termite, five termites or a number of termites between 20 and 40 either near to or far from the entrance and observed the ensuing behaviors. G. menadensis recruited others when encountering multiple termites regardless of the termite pile's distance from the nest, although a few individuals remained at the site and defended the resource. The pattern of arrivals at the site indicates that the majority and sometimes all arrivals were recruited from the branch trails. In combination, these results suggest that the architecture of the foraging habitat, which limits available return routes to the nest and thus increases encounter probabilities with potential recruits, shaped the process of information transfer and generated a collective pattern of foraging and prey retrieval.

Response of Diamond-Blackfan anemia to metoclopramide: evidence for a role for prolactin in erythropoiesis.

A 47-year-old woman with severe macrocytic anemia markedly improved during the second and third trimesters of 3 pregnancies and when breast-feeding her 2 children. Because the serum prolactin level is elevated at these times, we later treated her with metoclopramide (10 mg orally 3 times daily), a medication known to induce prolactin release. Her serum prolactin levels increased from 7 to 133 ng/mL (normal < 20 ng/mL) and hematocrit from 17% to 22% to 35%. With continued therapy (now 10 mg orally daily), her hematocrit has ranged from 30% to 40% for 6 years, although the macrocytosis persists (mean corpuscular volume, 100-112 fL). On the basis of this observation, a pilot study was undertaken of metoclopramide therapy in patients with Diamond-Blackfan anemia who were refractory to low doses of corticosteroids. Fifteen patients were enrolled and 9 completed the planned 16 weeks of therapy. Three individuals responded, suggesting that this therapeutic approach may benefit others. As with the index case, the anemia did not improve until 12 to 15 weeks of therapy had been completed.

Interpretation of fetal hemoglobin only on newborn screening for hemoglobinopathy.

Newborn screening for hemoglobinopathies rarely produces a fetal hemoglobin only result; it is most consistent with beta-thalassemia major, although other diagnoses are possible. The authors describe two unrelated African-American babies born in North Carolina whose newborn screening revealed fetal hemoglobin only. Both had a relatively benign clinical and hematologic picture. Molecular analyses indicated that both children are compound heterozygotes for beta-thalassemia and pancellular (deletional) hereditary persistence of fetal hemoglobin, a rare and apparently benign condition. Accurate interpretation of the fetal hemoglobin only result on newborn screening requires thorough evaluation, including family studies and molecular analysis.