Behavioral adaptations and the minimization of reproductive costs in the male red-sided garter snake, Thamnophis sirtalis parietalis.

The benefits of reproduction are clear, but there are also costs. Much is known about the costs of reproduction in females, but only recently have male costs been investigated in any depth. These costs of reproduction may be minimized by appropriately modifying behavior, but there has been little research on such behavioral minimization, especially in males. Male red-sided garter snakes, Thamnophis sirtalis parietalis, are an excellent model for the study of reproductive behavior because they form large breeding aggregations and tolerate human observation and manipulation. They are particularly useful for the study of reproductive costs because their investment in reproduction ends at copulation, and thus all reproductive effort is spatially and temporally constrained to the breeding sites during the breeding season. We investigated two ways in which male garter snakes use behavior to minimize reproductive costs. First, we investigated whether male garter snakes can discriminate between the pheromone trails of mated and unmated females. After mating, females are unable to remate for two to four days due to a mating plug that occludes their cloaca. As males search for females by following their pheromone trails, they are exposed to high costs in terms of energetics, risk of predation, and lost opportunities with other females. Males discriminated between the pheromone trails of mated and unmated females, and they preferentially followed the trails of unmated females. They followed mated females once the mating plug had disintegrated and the female was able to remate. These results suggest that by discriminating between the trails of mated and unmated females, males can minimize the costs associated with searching for females by preferentially following females that provide a mating opportunity over those with which mating is not possible. Second, we investigated seasonal anorexia in male garter snakes. Despite high daily energy expenditure in the breeding season and eight months of aphagia preceding the breeding season, males are never found with prey items in their stomachs at the dens. This aphagia has been attributed to extrinsic causes (a lack of prey at the dens) and to intrinsic causes (seasonal anorexia). We determined that males at the breeding grounds exhibit a seasonal anorexia, whereby they show no interest in feeding during the breeding season. This anorexia appears to be adaptive in light of the high cost of searching for prey during the breeding season. We conclude that male garter snakes adjust their behavior to minimize the costs of reproduction. However, at this point our understanding of the nature of these costs is primarily qualitative. Future work should expand our knowledge of the costs associated with reproduction, especially in quantifying costs experienced by the male. Historically these costs have been neglected.Keywords: mate choice, reproduction, pheromone, Red-sided garter snake (Thamnophis sirtalis parietalis), feeding, behavio

Surface and electronic structure of MOCVD-grown Ga(0.92)In(0.08)N investigated by UV and X-ray photoelectron spectroscopies

The surface and electronic structure of MOCVD-grown layers of Ga(0.92)In(0.08)N have been investigated by means of photoemission. An additional feature at the valence band edge, which can be ascribed to the presence of In in the layer, has been revealed. A clean (0001)-(1x1) surface was prepared by argon ion sputtering and annealing. Stability of chemical composition of the investigated surface subjected to similar ion etching was proven by means of X-ray photoemission spectroscopy.Comment: 13 pages, 6 figure

911 Calls for Emergency Medical Services in Heart Failure: A Descriptive Qualitative Study

Background Heart failure (HF) is a common condition leading to activation of emergency medical services (EMS). Objective The aim of this study was to describe reasons given by persons with HF, family members, or other caregivers for requesting EMS activation during 911 calls. Methods In this descriptive qualitative study, a content analysis was performed on transcribed audio files of 383 EMS requests involving 383 persons with HF in the community. Results One hundred forty-seven calls (38.4%) were placed by the family members, 75 (19.6%) were placed by the patients, 56 (14.6%) were placed by healthcare workers or personnel from living facilities, and the remaining calls (n = 105, 27.4%) were placed by others (eg, friends, neighbors, officers). Three broad categories of symptoms, signs, and events were identified as the reasons for an EMS request. Frequently reported symptoms were breathing problems (55.4%), chest pain (18.3%), and other pain (eg, head, extremities) (16.7%). Signs included decreased consciousness (15.4%), swelling (5.7%), and bleeding (5.0%). The reported events involved falls (8.1%), heart attack (6.3%), hypoxic episodes (6.0%), stroke (5.2%), and post–hospital-discharge complications (4.7%). In most calls (74.9%), multiple reasons were reported and a combination of symptoms, signs, and events were identified. Heart failure diagnosis was mentioned in fewer than 10% of the calls. Conclusions Overall, symptoms and signs of HF exacerbation were common reasons to activate 911 calls. Falls were frequently reported. Under the duress of the emergent situations surrounding the 911 call, callers rarely mentioned the existence of HF. Interventions are needed to guide patients with HF and their family members to promote the management of HF to reduce EMS activation as well as to activate EMS quickly for acute changes in HF conditions

Ward Identities, B-> \rho Form Factors and |V_ub|

The exclusive FCNC beauty semileptonic decay B-> \rho is studied using Ward identities in a general vector meson dominance framework, predicting vector meson couplings involved. The long distance contributions are discussed which results to obtain form factors and |V_ub|. A detailed comparison is given with other approaches.Comment: 30 pages+four postscript figures, an Appendix adde

Sustained VWF‐ADAMTS‐13 axis imbalance and endotheliopathy in long COVID syndrome is related to immune dysfunction

Background Prolonged recovery is common after acute SARS-CoV-2 infection; however, the pathophysiological mechanisms underpinning Long COVID syndrome remain unknown. VWF/ADAMTS-13 imbalance, dysregulated angiogenesis, and immunothrombosis are hallmarks of acute COVID-19. We hypothesized that VWF/ADAMTS-13 imbalance persists in convalescence together with endothelial cell (EC) activation and angiogenic disturbance. Additionally, we postulate that ongoing immune cell dysfunction may be linked to sustained EC and coagulation activation. Patients and methods Fifty patients were reviewed at a minimum of 6 weeks following acute COVID-19. ADAMTS-13, Weibel Palade Body (WPB) proteins, and angiogenesis-related proteins were assessed and clinical evaluation and immunophenotyping performed. Comparisons were made with healthy controls (n = 20) and acute COVID-19 patients (n = 36). Results ADAMTS-13 levels were reduced (p = 0.009) and the VWF-ADAMTS-13 ratio was increased in convalescence (p = 0.0004). Levels of platelet factor 4 (PF4), a putative protector of VWF, were also elevated (p = 0.0001). A non-significant increase in WPB proteins Angiopoietin-2 (Ang-2) and Osteoprotegerin (OPG) was observed in convalescent patients and WPB markers correlated with EC parameters. Enhanced expression of 21 angiogenesis-related proteins was observed in convalescent COVID-19. Finally, immunophenotyping revealed significantly elevated intermediate monocytes and activated CD4+ and CD8+ T cells in convalescence, which correlated with thrombin generation and endotheliopathy markers, respectively. Conclusion Our data provide insights into sustained EC activation, dysregulated angiogenesis, and VWF/ADAMTS-13 axis imbalance in convalescent COVID-19. In keeping with the pivotal role of immunothrombosis in acute COVID-19, our findings support the hypothesis that abnormal T cell and monocyte populations may be important in the context of persistent EC activation and hemostatic dysfunction during convalescence

Bronchiectasis insanity:Doing the same thing over and over again and expecting different results?

Bronchiectasis is an increasingly common disease with a significant impact on quality of life and morbidity of affected patients. It is also a very heterogeneous disease with numerous different underlying etiologies and presentations. Most treatments for bronchiectasis are based on low-quality evidence; consequently, no treatments have been approved by the US Food and Drug Administration or the European Medicines Agency for the treatment of bronchiectasis. The last several years have seen numerous clinical trials in which the investigational agent, thought to hold great promise, did not demonstrate a clinically or statistically significant benefit. This commentary will review the likely reasons for these disappointing results and a potential approach that may have a greater likelihood of defining evidence-based treatment for bronchiectasis

Bone defects following curettage do not necessarily need augmentation: A retrospective study of 146 patients

Background and purpose The natural pattern of bone healing in large bony defects following curettage alone as treatment of benign bone tumors around the knee is not well reported. We analyzed the outcome in 146 patients

Molecular Biomarkers of Vascular Dysfunction in Obstructive Sleep Apnea

Untreated and long-lasting obstructive sleep apnea (OSA) may lead to important vascular abnormalities, including endothelial cell (EC) dysfunction, hypertension, and atherosclerosis. We observed a correlation between microcirculatory reactivity and endothelium-dependent release of nitric oxide in OSA patients. Therefore, we hypothesized that OSA affects (micro)vasculature and we aimed to identify vascular gene targets of OSA that could possibly serve as reliable biomarkers of severity of the disease and possibly of vascular risk. Using quantitative RT-PCR, we evaluated gene expression in skin biopsies of OSA patients, mouse aortas from animals exposed to 4-week intermittent hypoxia (IH; rapid oscillations in oxygen desaturation and reoxygenation), and human dermal microvascular (HMVEC) and coronary artery endothelial cells (HCAEC) cultured under IH. We demonstrate a significant upregulation of endothelial nitric oxide synthase (eNOS), tumor necrosis factor-alpha-induced protein 3 (TNFAIP3; A20), hypoxia-inducible factor 1 alpha (HIF-1α?? and vascular endothelial growth factor (VEGF) expression in skin biopsies obtained from OSA patients with severe nocturnal hypoxemia (nadir saturated oxygen levels [SaO2]<75%) compared to mildly hypoxemic OSA patients (SaO2 75%–90%) and a significant upregulation of vascular cell adhesion molecule 1 (VCAM-1) expression compared to control subjects. Gene expression profile in aortas of mice exposed to IH demonstrated a significant upregulation of eNOS and VEGF. In an in vitro model of OSA, IH increased expression of A20 and decreased eNOS and HIF-1α expression in HMVEC, while increased A20, VCAM-1 and HIF-1αexpression in HCAEC, indicating that EC in culture originating from distinct vascular beds respond differently to IH stress. We conclude that gene expression profiles in skin of OSA patients may correlate with disease severity and, if validated by further studies, could possibly predict vascular risk in OSA patients