Tactical adjustment of signaling leads to increased mating success and survival

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioral solutions exist for overcoming such environmental variability, including the adjustment of signaling behavior based upon receiver feedback. Few studies have directly examined the relationship between such tactical signaling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following exposure to female receptivity cues, some males increased their signaling on an effective signaling substrate (filter paper) while others decreased signaling on the effective substrate. These groups of males were then run through mating trials, conducted in a heterogeneous environment, to examine the relationship between male signaling adjustments and subsequent mating success. Males that adaptively adjusted their signaling (i.e. increased signaling on a more effective substrate) were (1) more likely to copulate, (2) achieved a copulation more quickly and (3) were less likely to be attacked; thus establishing a positive relationship between tactical adjustments of courtship signaling and male fitness

Tactical adjustment of signaling leads to increased mating success and survival

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioral solutions exist for overcoming such environmental variability, including the adjustment of signaling behavior based upon receiver feedback. Few studies have directly examined the relationship between such tactical signaling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following exposure to female receptivity cues, some males increased their signaling on an effective signaling substrate (filter paper) while others decreased signaling on the effective substrate. These groups of males were then run through mating trials, conducted in a heterogeneous environment, to examine the relationship between male signaling adjustments and subsequent mating success. Males that adaptively adjusted their signaling (i.e. increased signaling on a more effective substrate) were (1) more likely to copulate, (2) achieved a copulation more quickly and (3) were less likely to be attacked; thus establishing a positive relationship between tactical adjustments of courtship signaling and male fitness

Molecular and Clinical Aspects of Targeting the VEGF Pathway in Tumors

Tumor angiogenesis is a complex process resulting from many signals from the tumor microenvironment. From preclinical animal models to clinical trials and practice, targeting tumors with antiangiogenic therapy remains an exciting area of study. Although many scientific advances have been achieved, leading to the development and clinical use of antiangiogenic drugs such as bevacizumab, sorafenib, and sunitinib, these therapies fall short of their anticipated benefits and leave many questions unanswered. Continued research into the complex signaling cascades that promote tumor angiogenesis may yield new targets or improve upon current therapies. In addition, the development of reliable tools to track tumor responses to antiangiogenic therapy will enable a better understanding of current therapeutic efficacy and may elucidate mechanisms to predict patient response to therapy

The complexities of female mate choice and male polymorphisms: Elucidating the role of genetics, age, and mate-choice copying

Genetic, life history, and environmental factors dictate patterns of variation in sexual traits within and across populations, and thus the action and outcome of sexual selection. This study explores patterns of inheritance, diet, age, and mate-choice copying on the expression of male sexual signals and associated female mate choice in a phenotypically diverse group of Schizocosa wolf spiders. Focal spiders exhibit one of two male phenotypes: ‘ornamented’ males possess large black brushes on their forelegs, and ‘non-ornamented’ males possess no brushes. Using a quantitative genetics breeding design in a mixed population of ornamented/non-ornamented males, we found a strong genetic basis to male phenotype and female choice. We also found that some ornamented males produced some sons with large brushes and others with barely visible brushes. Results of diet manipulations and behavioral mating trials showed no influence of diet on male phenotype or female mate choice. Age post maturation, however, influenced mate choice, with younger females being more likely to mate with ornamented males. A mate-choice copying experiment found that, following observations of another female’s mate choice/copulation, virgin mature females tended to match the mate choice (ornamented vs. non-ornamented males) of the females they observed. Finally, analyses of genetic variation across phenotypically pure (only one male phenotype present) vs. mixed (both phenotypes present) populations revealed genetic distinction between phenotypes in phenotypically-pure populations, but no distinction in phenotypically-mixed populations. The difference in patterns of genetic differentiation and mating across geographic locations suggests a complex network of factors contributing to the outcome of sexual selection

Designing Assignments to Establish a Foundation for Evidenceâ Based Practice in an Undergraduate Clinical Nursing Course

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142903/1/wvn12198.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142903/2/wvn12198_am.pd

The complexities of female mate choice and male polymorphisms: Elucidating the role of genetics, age, and mate-choice copying

Genetic, life history, and environmental factors dictate patterns of variation in sexual traits within and across populations, and thus the action and outcome of sexual selection. This study explores patterns of inheritance, diet, age, and mate-choice copying on the expression of male sexual signals and associated female mate choice in a phenotypically diverse group of Schizocosa wolf spiders. Focal spiders exhibit one of two male phenotypes: ‘ornamented’ males possess large black brushes on their forelegs, and ‘non-ornamented’ males possess no brushes. Using a quantitative genetics breeding design in a mixed population of ornamented/non-ornamented males, we found a strong genetic basis to male phenotype and female choice. We also found that some ornamented males produced some sons with large brushes and others with barely visible brushes. Results of diet manipulations and behavioral mating trials showed no influence of diet on male phenotype or female mate choice. Age post maturation, however, influenced mate choice, with younger females being more likely to mate with ornamented males. A mate-choice copying experiment found that, following observations of another female’s mate choice/copulation, virgin mature females tended to match the mate choice (ornamented vs. non-ornamented males) of the females they observed. Finally, analyses of genetic variation across phenotypically pure (only one male phenotype present) vs. mixed (both phenotypes present) populations revealed genetic distinction between phenotypes in phenotypically-pure populations, but no distinction in phenotypically-mixed populations. The difference in patterns of genetic differentiation and mating across geographic locations suggests a complex network of factors contributing to the outcome of sexual selection

Sentinel Lymph Node Biopsy Does Not Improve Disease-Specific Survival in Elderly Patients with Intermediate Thickness Melanoma

Objective: To determine whether sentinel lymph node biopsy (SLNB) is associated with improved disease-specific survival among elderly patients with intermediate-thickness melanoma Design: Retrospective cohort study of prospectively-maintained tumor registry Setting: Single institution tertiary care center. P atients: Adults ≥ 70 years of age, who underwent surgical intervention for melanoma from 2000-2013. Main Outcome Measures: The primary outcomes were overall survival (OS) and disease-free survival (DFS). Other clinicopathologic variables measured included age, gender, anatomic site, histologic type, tumor thickness, presence of adverse features, receipt and result of SLNB, and receipt of completion lymph node dissection (CLND). Results: Ninety-one patients (mean age 80 years, 54% male) underwent wide excision of an intermediate-thickness melanoma. Forty-nine patients (54%) received a SLNB. Seven of these biopsies (14%) were positive, and five patients (71%) went on to receive CLND. Five-year OS was 41% in patients who did not receive SLNB and 52% in patients who did receive SLNB (Fig. 1A). However, 5-year DFS was 79% in patients who did not receive SLNB and 77% in patients who did receive SLNB (Fig. 1B). Conclusions: Among elderly patients with intermediate-thickness melanoma, patients who received SLNB had higher 5-year OS than those who did not receive SLNB. However, the 5-year DFS is similar between the two groups, which suggests that the OS differences are related to non-melanoma factors. Routine SLNB for intermediate-thickness melanoma patients may not significantly change the outcome for this age group, and clinical decision-making should consider individual patient comorbidities and goals of care

Mothers in the Military: Effect of Maternity Leave Policy on Take-Up

DRAFT VersionThe article of record as published may be found at https://doi.org/10.1215/00703370-9816044The United States remains the only OECD nation without national paid maternity leave. This paper exploits changes in paid maternity leave offered by one of its largest employers, the U.S. Department of Defense. Since 2015, the U.S. Marine Corps has shifted their maternity leave policy from six to 18 to 12 weeks. Leave expansions increased leave duration while contractions decreased leave taken by active-duty service members. However, the policy changes crowded out other forms of leave: with an increase in maternity leave available, mothers increased use of maternity leave and stopped supplementing with additional annual leave. Though all mothers used the full six weeks of leave in the early period, it is the less advantaged mothers—in the enlisted ranks, first-time, and single mothers—who disproportionately used more of the additional leave than officers, experienced mothers, and married mothers. Pregnant officers, experienced mothers, and single women use less leave than non-pregnant women in the months leading up to birth, but expecting additional post-birth leave did not change average pre-birth leave-taking. Our results highlight the importance of optimally sizing family leave policies and provide evidence that the true cost of such programs may be lower than the raw count of weeks provided by additional maternity leave allowances