Fluctuating survival selection explains variation in avian group size.

Most animal groups vary extensively in size. Because individuals in certain sizes of groups often have higher apparent fitness than those in other groups, why wide group size variation persists in most populations remains unexplained. We used a 30-y mark-recapture study of colonially breeding cliff swallows (Petrochelidon pyrrhonota) to show that the survival advantages of different colony sizes fluctuated among years. Colony size was under both stabilizing and directional selection in different years, and reversals in the sign of directional selection regularly occurred. Directional selection was predicted in part by drought conditions: birds in larger colonies tended to be favored in cooler and wetter years, and birds in smaller colonies in hotter and drier years. Oscillating selection on colony size likely reflected annual differences in food availability and the consequent importance of information transfer, and/or the level of ectoparasitism, with the net benefit of sociality varying under these different conditions. Averaged across years, there was no net directional change in selection on colony size. The wide range in cliff swallow group size is probably maintained by fluctuating survival selection and represents the first case, to our knowledge, in which fitness advantages of different group sizes regularly oscillate over time in a natural vertebrate population.

Costs and benefits of late nesting in cliff swallows.

Many organisms of temperate latitudes exhibit declines in reproductive success as the breeding season advances. Experiments can delay the onset of reproduction for early breeders to investigate the consequences of late nesting, but it is rarely possible to observe a distinct second round of nesting in species that normally nest only once. The colonial cliff swallow (Petrochelidon pyrrhonota) is a migratory songbird that has a relatively short breeding season in the western Great Plains, USA, with birds rarely nesting late in the summer. Previous work suggested that ectoparasitism is a primary reason why reproductive success in this species declines over the summer. At colony sites where nests were fumigated to remove ectoparasitic swallow bugs (Oeciacus vicarius), cliff swallows frequently undertook a distinct round of late nesting after previously fledging young that year. Mark-recapture revealed that late-nesting pairs at these colonies produced fewer offspring that survived to the next breeding season, and that survival of late-nesting adults was lower during the next year, relative to pairs nesting earlier in the season. These reproductive costs applied in the absence of ectoparasites and likely reflect other environmental costs of late nesting such as seasonal declines in food availability or a delayed start of fall migration. Despite the costs, the estimated fitness for perennial early-and-late nesters in the absence of ectoparasites was equivalent to that of birds that nested only early in the season. The collective disadvantages of late nesting likely constrain most cliff swallows to raising a single brood in the middle latitudes of North America.

Variation in age composition among colony sizes in Cliff Swallows.

Variation in group size is characteristic of most social species. The extent to which individuals sort among group sizes based on age may yield insight into why groups vary in size and the age-specific costs and benefits of different social environments. We investigated the age composition of Cliff Swallow (Petrochelidon pyrrhonota) colonies of different sizes over 18 years at a long-term study site in western Nebraska, USA. Using years elapsed since banding as a relative measure of age for over 194,000 birds, we found that the proportion of age-class-1 swallows (birds banded as nestlings or juveniles or adults in the year of banding) of both sexes increased in larger colonies and at colony sites becoming active later in the summer. Age composition was unrelated to how often a particular colony site was used. The effect of colony size most likely reflected the fact that older birds return to the same colony site in successive years even when the colony size there decreases, and that yearlings and immigrants benefit more from larger colonies than do older, more experienced individuals. The date effect probably resulted in part from later spring arrival by younger and/or immigrant swallows. At fumigated sites where ectoparasitic swallow bugs (Oeciacus vicarius) had been removed, age composition did not vary with either colony size or colony initiation date. The patterns reported here appear to be driven partially by the presence of ectoparasites and suggest that the hematophagous bugs influence variation in Cliff Swallow group composition. Our results are consistent with the hypothesis that variation in colony size reflects, in part, age-based sorting of individuals among groups.

Sampling tomorrow's lunch today: Examining the effect of sampling a vegetable-focused entrée on school lunch participation, a pilot study.

School lunch programs are important pillars in the food system, as they impact children's health, local agriculture, and community food security. When offering a new lunch entrée that contains vegetables, schools must consider whether students will choose the new entrée to avoid low participation rates and decreased revenue. Previous research in marketing suggests that sampling (i.e. taste testing) can positively impact consumer choice. In terms of encouraging students to eat school lunch and particularly items that include vegetables, it is often assumed that sampling will help direct food choice to healthier items, but little research has investigated the impact of sampling on food choice in a school lunch environment. The objective of this research was to investigate in a pilot study whether providing samples of a vegetable-focused lunch entrée the day before it appeared on the school lunch menu increased National School Lunch Program (NSLP) participation. The study took place at a Vermont middle school in 2015. Four new vegetable-focused entrées were supplied over three consecutive months. During month two, the entrées were sampled at a middle school the day before they were offered for sale, and NSLP participation, as well as revenue was tracked over three months. Our results suggest that sampling may have a positive impact on NSLP participation rates and food service revenue, but that more research is needed to better assess how sampling can be utilized in the most efficacious way to promote NSLP participation and healthy eating patterns.

Why come back home? Breeding-site fidelity varies with group size and parasite load in a colonial bird.

Fidelity to a past breeding site is widespread among animals and may confer both costs and benefits. Colonial species occur at specific sites that can accommodate multiple breeders, and the choice of whether to return to last year's site or disperse elsewhere can affect colony site use, the colony size distribution and individual fitness. For the colonial cliff swallow, Petrochelidon pyrrhonota, which occupies colonies of widely different sizes, we used a 30-year field study in western Nebraska to investigate how the extent of infestation by ectoparasites and colony size affected breeders' colony site fidelity between years. We compared philopatry at colonies where parasitic swallow bugs, Oeciacus vicarius, had been removed by fumigation with that at nonfumigated sites exposed to natural levels of ectoparasites. About 25% of birds at nonfumigated colonies returned to their previous year's site, whereas about 69% of birds at fumigated colonies did so. Site fidelity was greatest at nonfumigated sites that changed the least in size between years. Birds were less likely to return to a nonfumigated site as the colony there became increasingly larger. Individuals philopatric to both nonfumigated and fumigated sites resided in colonies more similar in size between years than did dispersing birds. Most cliff swallows settled within 6 km of their previous year's site, indicating that many nonphilopatric birds still may have had some familiarity with the local landscape surrounding the site to which they moved. Removal of ectoparasites at a site allows large colonies to persist there perennially, probably contributing to higher philopatry because such large colonies are rare and would have been difficult to find had the residents dispersed. Cliff swallows are likely to be sensitive to both colony size and general familiarity with a given site or landscape region, and probably integrate these with other cues to select breeding colonies.

Endovascular management of acute deep vein thrombosis.

The goals of successful management of deep vein thrombosis (DVT) include relief of acute symptoms with restoration of venous patency, prevention of clot propagation and subsequent pulmonary embolism, and maintenance of venous valvular function. Valvular incompetence is the leading cause of postthrombotic syndrome (PTS), which is characterized by chronic leg heaviness and aching, lower extremity edema, and impaired viability of subcutaneous tissues, which may lead to chronic trophic skin changes and venous ulceration. Anticoagulation with unfractionated or low-molecular-weight heparin followed by warfarin is recognized as the standard therapy for acute DVT. Although this approach may effectively prevent recurrent thrombosis, it often fails to meet the other treatment goals. Recent studies have demonstrated that early clot lysis through the use of catheter-directed thrombolytic therapy and other adjunctive endovascular techniques rapidly restores venous patency, more effectively preserves valvular function, and improves quality of life. When used in conjunction with anticoagulation, these minimally invasive endovascular techniques have the potential to lead to improved long-term outcomes in patients with DVT.

Comorbidity of bipolar disorder and substance abuse in Costa Rica: pedigree- and population-based studies.

BACKGROUND: The purpose of this study was to determine the prevalence of substance use disorders (substance abuse or substance dependence: SA/SD) in a large sample of Bipolar Type I (BPI) patients drawn from the Costa Rican population and to describe the effects of SA/SD on the course of their bipolar disorder. METHOD: 110 subjects from two high-risk (for BPI) Costa Rican pedigrees and 205 unrelated Costa Rican BPI subjects were assessed using structured interviews and a best estimate process. Chi(2) and survival analyses were performed to assess the effect of gender on comorbidity risk, and the effect of comorbidity on the clinical course of BPI. RESULTS: SA/SD (primarily alcohol dependence) occurred in 17% of the BPI patients from the population sample and 35% of the BPI patients from the pedigree sample. Comorbid SA/SD was strongly associated with gender chi(2) = 16.84, P = 0.00004). In comorbid subjects, alcohol dependence tended to predate the first manic episode (chi(2) = 6.54, P < 0.025). History of SA/SD did not significantly alter the prevalence of psychosis or age of onset of mania in BPI subjects. CONCLUSIONS: These results suggest that SA/SD comorbidity rates are lower in this type of population than in BPI patient populations in the US. Gender is a strong predictor of comorbidity prevalence in BPI patients from this population. Although SA/SD may be a risk factor for precipitating BPI in those at risk, in this population comorbid BPI subjects do not have a different onset or course of BPI in comparison to BPI patients without comorbidity.

Technological and Organizational Context around Immunization Reporting and Interoperability in Minnesota.

BACKGROUND: Immunization information systems (IIS) operate in an evolving health care landscape with technology changes driven by initiatives such as the Centers for Medicare and Medicaid Services EHR incentive program, promoting adoption and use of electronic health record (EHR) systems, including standards-based public health reporting. There is flux in organizational affiliations to support models such as accountable care organizations (ACO). These impact institutional structure of how reporting of immunizations occurs and the methods adopted. OBJECTIVES: To evaluate the technical and organizational characteristics of healthcare provider reporting of immunizations to public health in Minnesota and to assess the adoption of standardized codes, formats and transport. METHODS: Data on organizations and reporting status was obtained from Minnesota IIS (Minnesota Immunization Information Connection: MIIC) by collating information from existing lists, specialized queries and review of annual reports. EHR adoption data of clinics was obtained in collaboration with informatics office supporting the Minnesota e-Health Initiative. These data from various sources were merged, checked for quality to create a current state assessment of immunization reporting and results validated with subject matter experts. RESULTS: Standards-based reporting of immunizations to MIIC increased to 708 sites over the last 3 years. A growth in automated real-time reporting occurred in 2013 with 143 new sites adopting the method. Though the uptake of message standards (HL7) has increased, the adoption of current version of HL7 and web services transport remains low. The EHR landscape is dominated by a single vendor (used by 40% of clinics) in the state. There is trend towards centralized reporting of immunizations with an organizational unit reporting for many sites ranging from 4 to 140 sites. CONCLUSION: High EHR adoption in Minnesota, predominance of a vendor in the market, and centralized reporting models present opportunities for better interoperability and also adaptation of strategies to fit this landscape. It is essential for IIS managers to have a good understanding of their constituent landscape for technical assistance and program planning purposes.

Recapture heterogeneity in cliff swallows: increased exposure to mist nets leads to net avoidance.

Ecologists often use mark-recapture to estimate demographic variables such as abundance, growth rate, or survival for samples of wild animal populations. A common assumption underlying mark-recapture is that all animals have an equal probability of detection, and failure to meet or correct for this assumption-as when certain members of the population are either easier or more difficult to capture than other animals-can lead to biased and inaccurate demographic estimates. We built within-year and among-years Cormack-Jolly-Seber recaptures-only models to identify causes of capture heterogeneity for a population of colonially nesting cliff swallows (Petrochelidon pyrrhonota) caught using mist-netting as a part of a 20-year mark-recapture study in southwestern Nebraska, U.S.A. Daily detection of cliff swallows caught in stationary mist nets at their colony sites declined as the birds got older and as the frequency of netting at a site within a season increased. Experienced birds' avoidance of the net could be countered by sudden disturbances that startled them into a net, such as when we dropped a net over the side of a bridge or flushed nesting cliff swallows into a stationary net positioned at a colony entrance. Our results support the widely held, but seldom tested, belief that birds learn to avoid stationary mist nets over time, but also show that modifications of traditional field methods can reduce this source of recapture heterogeneity.

Social cognitive theory as a framework for considering Farm to School programming.

BACKGROUND: Farm to School (FTS) programs are designed, in part, to improve childhood health and nutrition and may be implemented as a strategy to prevent childhood obesity. FTS programs have largely emerged out of grassroots efforts, and theory has not explicitly guided program development or implementation. This research considers the effectiveness of social cognitive theory (SCT) as a framework for FTS programming. METHODS: In 2010, a survey was administered to 632 elementary schoolchildren in Vermont. Six indices were developed from 46 variables that measured personal characteristics and experiences with regard to fruits and vegetables, as described in the SCT. RESULTS: These indices were the basis for cluster analysis, which identified three distinct clusters. Bivariate analysis showed significant differences among the clusters in the children's likelihood of meeting the Dietary Guidelines for Americans (DGA). The significant differences observed among the clusters suggest that SCT is an appropriate framework within which FTS interventions may be considered. CONCLUSIONS: The findings show that there are distinct food-related attitudes and behaviors that differ widely by the SCT informed clusters and that can be used to inform FTS programs.

Heritable choice of colony size in cliff swallows: does experience trump genetics in older birds?

The variation in breeding-colony size seen in populations of most colonial birds may reflect heritable choices made by individuals who are phenotypically specialized for particular social environments. Although a few studies have reported evidence for genetically based choice of group sizes in birds, we know relatively little about the extent to which animals potentially rely on experience versus innate preferences in deciding with how many conspecifics to settle at different times of their lives. We conducted a cross-fostering experiment in 1997-1998 on cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, USA, in which some individuals were reared in colonies different in size from those in which they were born. Breeding-colony sizes chosen by this cohort of birds were monitored by mark-recapture throughout their lives. A multistate mark-recapture analysis revealed that birds in their first breeding year chose colony sizes similar to those of their birth, regardless of their rearing environment, confirming a previous analysis. Beyond the first breeding year, however, cliff swallows' colony choice was less dependent on where they were born. Birds born in small colonies and reared in large colonies showed evidence of a delayed rearing effect, with these birds overwhelmingly choosing large colonies in later years. Heritabilities suggested strong genetic effects on first-year colony choice but not in later years. Cliff swallows' genetically based colony-size preferences their first year could be a way to ensure matching of their phenotype to an appropriate social environment as yearlings. In later years, familiarity with particular colony sites and available information on site quality may override innate group-size preferences when birds choose colonies.

'It's a boy because he's painting a picture': age differences in children's conventional and unconventional gender schemas.

Two studies investigated the development of children's gender knowledge using a procedure designed to tap into children's unconventional gender beliefs. Study 1 revealed a developmental progression with 34 3- to 4-year-old children providing more unconventional reasons than conventional reasons to explain the gender of a series of drawings. By contrast, 39 5- to 6-year-old and 42 7- to 8-year-old children provided more conventional than unconventional reasons. Study 2 found that a second sample of 42 3- to 4-year-old children mastered a close-ended assessment of gender stereotyping, while they relied on unconventional and conventional reasoning equally when explaining the gender of a series of drawings displaying conventional cues only. This research supports the model that children's conventional gender schemas do not develop before their unconventional gender schemas.

Genomewide linkage disequilibrium mapping of severe bipolar disorder in a population isolate.

Genomewide association studies may offer the best promise for genetic mapping of complex traits. Such studies in outbred populations require very densely spaced single-nucleotide polymorphisms. In recently founded population isolates, however, extensive linkage disequilibrium (LD) may make these studies feasible with currently available sets of short tandem repeat markers, spaced at intervals as large as a few centimorgans. We report the results of a genomewide association study of severe bipolar disorder (BP-I), using patients from the isolated population of the central valley of Costa Rica. We observed LD with BP-I on several chromosomes; the most striking results were in proximal 8p, a region that has previously shown linkage to schizophrenia. This region could be important for severe psychiatric disorders, rather than for a specific phenotype.