Silver-spoon upbringing improves early-life fitness but promotes reproductive ageing in a wild bird

Early-life conditions can have long-lasting effects and organisms that experience a poor start in life are often expected to age at a faster rate. Alternatively, individuals raised in high-quality environments can overinvest in early-reproduction resulting in rapid ageing. Here we use a long-term experimental manipulation of early-life conditions in a natural population of collared flycatchers (Ficedula albicollis), to show that females raised in a low-competition environment (artificially reduced broods) have higher early-life reproduction but lower late-life reproduction than females raised in high-competition environment (artificially increased broods). Reproductive success of high-competition females peaked in late-life, when low-competition females were already in steep reproductive decline and suffered from a higher mortality rate. Our results demonstrate that ‘silver-spoon’ natal conditions increase female early-life performance at the cost of faster reproductive ageing and increased late-life mortality. These findings demonstrate experimentally that natal environment shapes individual variation in reproductive and actuarial ageing in nature

The innovative aspects of the fishing fleet development in the Russian exclave region

Our country has set a course for the economy modernisation on the basis of innovative development. In the post-war period until 1991, the exclave of Russia — the Kaliningrad region — showed high rates of socioeconomic development due to the establishment of a large- scale sea fishing industry. Such success rested on research and innovative activity. This article analyses the successful innovative development of the fishing fleet in the historical perspective: new vessels, the development of new equipment, introduction of innovative forms of fishing organisation. The authors offer data on the efficiency of such innovative initiatives. This historical experience is of great importance given the revival of industrial fishing in the Kaliningrad region

Stress Urinary Incontinence post-Holmium Laser Enucleation of the Prostate: a Single-Surgeon Experience.

PURPOSE: To identify incidence and predictors of stress urinary incontinence (SUI) following Holmium laser enucleation of the prostate (HoLEP). MATERIALS AND METHODS: We performed a retrospective review of 589 HoLEP patients from 2012-2018. Patients were assessed at pre-operative and post-operative visits. Univariate and multivariate regression analyses were performed to identify predictors of SUI. RESULTS: 52/589 patients (8.8%) developed transient SUI, while 9/589 (1.5%) developed long-term SUI. tSUI resolved for 46 patients (88.5%) within the first six weeks and in 6 patients (11.5%) between 6 weeks to 3 months. Long-term SUI patients required intervention, achieving continence at 16.4 months on average, 44 men (70.9%) with incontinence were catheter dependent preoperatively. Mean prostatic volume was 148.7mL in tSUI patients, 111.6mL in long-term SUI, and 87.9mL in others (p \u3c 0.0001). On univariate analysis, laser energy used (p \u3c 0.0001), laser on time (p=0.0204), resected prostate weight (p \u3c 0.0001), overall International Prostate Symptom Score (IPSS) (p=0.0005), and IPSS QOL (p=0.02) were associated with SUI. On multivariate analysis, resected prostate weight was predictive of any SUI and tSUI, with no risk factors identified for long-term SUI. CONCLUSION: Post-HoLEP SUI occurs in ~10% of patients, with 1.5% continuing beyond six months. Most patients with tSUI recover within the first six weeks. Prostate size \u3e100g and catheter dependency are associated with increased risk tSUI. Larger prostate volume is an independent predictor of any SUI, and tSUI

Can sexual selection theory inform genetic management of captive populations? A review

International audienceCaptive breeding for conservation purposes presents a serious practical challenge because several conflicting genetic processes (i.e., inbreeding depression, random genetic drift and genetic adaptation to captivity) need to be managed in concert to maximize captive population persistence and reintroduction success probability. Because current genetic management is often only partly successful in achieving these goals, it has been suggested that management insights may be found in sexual selection theory (in particular, female mate choice). We review the theoretical and empirical literature and consider how female mate choice might influence captive breeding in the context of current genetic guidelines for different sexual selection theories (i.e., direct benefits, good genes, compatible genes, sexy sons). We show that while mate choice shows promise as a tool in captive breeding under certain conditions, for most species, there is currently too little theoretical and empirical evidence to provide any clear guidelines that would guarantee positive fitness outcomes and avoid conflicts with other genetic goals. The application of female mate choice to captive breeding is in its infancy and requires a goal-oriented framework based on the needs of captive species management, so researchers can make honest assessments of the costs and benefits of such an approach, using simulations, model species and captive animal data

Hrdinové a oběti bez ničemů. Mor v raně novověké Praze

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Mechanisms of Improving Collateral Blood Flow During Ischemic Stroke

Undergraduate Scholarship Competitions Administered by the ASC Honors ProgramMore than 795,000 Americans suffer a stroke annually, and it is the third leading cause of death in the United States1. There are two types of stroke, hemorrhagic and ischemic. Hemorrhagic stroke is caused by the rupture of blood vessels within the brain, as opposed to ischemic strokes, which are caused by a blockage within the vessel. Of all strokes presented clinically, 86% are ischemic by nature1. Currently, there are few treatments for ischemic stroke. The prevailing early treatments include thrombolytic therapy and antiplatelet therapy such as low dose aspirin2,3. These treatments are each flawed. Tissue plasminogen activator (tPA) is currently the only FDA-approved thrombolytic therapy for the acute treatment of ischemic stroke4. This treatment is approved for less than 10% of patients, and is given to less than 4%4. In addition, greater than 65% of hospitals in America have never administered tPA to patients due to low efficacy as well as potential harmful side effects5. Antiplatelets, such as low dose aspirin, are another treatment option. These are drugs, and therefore have negative side effects associated with long-term use such as increased risk of hemorrhagic stroke6, and gastrointestinal bleeding7. As a result, there is a distinct lack of safe therapeutic options for both the early and long-term treatment of ischemic stroke patients. Cerebrovascular collaterals refer to the network of blood vessels that are clinically documented to perfuse stroke-affected tissue during ischemic stroke and reduce brain injury8. While strategies to improve collateral blood flow during stroke are of significant therapeutic interest, mechanisms and a means to improve circulation through these blood vessels during stroke remain unknown. This honors thesis proposal rests on a key in vivo observation that supplementation of a lesser-characterized natural vitamin E, alpha-tocotrienol (TCT), improves cerebrovascular collateral blood flow and attenuates stroke injury8. TCT therefore serves as a powerful tool to study cerebrovascular collateral remodeling during stroke. The overall objective of this honors thesis will be to characterize the effects of TCT on cerebrovascular collateral perfusion during stroke and to identify a mechanistic basis for TCT improvement of cerebrovascular collateral circulation. Many previously identified arteriogenic markers, including Tissue inhibitor of metalloproteinase 1 (TIMP1), will be investigated as a known molecular target of interest for induction of collateral growth in the brain. FITC-lectin tagging of cerebrovascular collaterals will be used for laser capture microdissection experiments and downstream molecular study of arteriogenic targets. This approach will enable the specific collection of perfused cerebrovascular collaterals from stroke-affected tissue for mechanistic study.Funding from research grants awarded to Dr. Cameron RinkNo embargoAcademic Major: Biolog

Photoperiodic Regulation of Cerebral Blood Flow in White-Footed Mice (Peromyscus leucopus)

Individuals living outside the tropics need to adjust their behavioral and physiological repertoires throughout the year to adapt to the changing seasons. White-footed mice (Peromyscus leucopus) reduce hippocampal volumes, hippocampal-dependent memory function, long-term potentiation, and alter neurogenesis in response to short (winter-like) day lengths (photoperiods). During winter, these mice putatively shunt energy away from the brain to maximize peripheral thermogenesis, immune function, and survival. We hypothesized that these changes in brain function are accompanied by alterations in brain vasculature. We maintained white-footed mice in short (8 h light/16 h dark) or long (16 h light/8 h dark) photoperiods for 8-9 weeks. Mice were then perfused with fluorescein isothiocyanate (FITC)-conjugated tomato (Lycopersicon esculentum) lectin to visualize the perfused cerebrovasculature. Short-day mice reduced hippocampal and cortical capillary density (FITC(+) area); vessels isolated from short day-exposed mice expressed higher mRNA levels of the gelatinase matrix metalloproteinase 2 (MMP2). Additionally, short-day mice reduced cerebral blood flow approximately 15% compared with their long-day counterparts, as assessed by laser speckle flowmetry. Immunohistochemistry revealed higher levels of MMP2 in the hippocampus of mice maintained in short days compared with long days, potentially contributing to the observed vascular remodeling. These data demonstrate that a discrete environmental signal (i.e., day length) can substantially alter cerebral blood flow in adult mammals

Dynamics of phenotypic change: wing length declines in a resident farmland passerine despite survival advantage of longer wings

In many taxa, environmental changes that alter resource availability and energetics, such as climate change and land use change, are associated with changes in body size. We use wing length as a proxy for overall structural body size to examine a paradoxical trend of declining wing length within a Yellowhammer Emberiza citrinella population sampled over 21 years, in which it has been previously shown that longer wings are associated with higher survival rates. Higher temperatures during the previous winter (prior to the moult determining current wing length) explained 23% of wing length decrease within our population, but changes may also be correlated with non-climatic environmental variation such as changes in farming mechanisms linked to food availability. We found no evidence for within-individual wing length shrinkage with age, but our data suggested a progressive decline in the sizes of immature birds recruiting to the population. This trend was weaker, although not significantly so, among adults, suggesting that the decline in the sizes of recruits was offset by higher subsequent survival of larger birds post-recruitment. These data suggest that ecological processes can contribute more than selection to observed phenotypic trends and highlight the importance of long-term studies for providing longitudinal insights into population processes

Does recognized genetic management in supportive breeding prevent genetic changes in life-history traits?

International audienceSupportive breeding is one of the last resort conservation strategies to avoid species extinction. Management of captive populations is challenging because several harmful genetic processes need to be avoided. Several recommendations have been proposed to limit these deleterious effects, but empirical assessments of these strategies remain scarce. We investigated the outcome of a genetic management in a supportive breeding for the Houbara Bustard. At the phenotypic level, we found an increase over generations in the mean values of gamete production, body mass and courtship display rate. Using an animal model, we found that phenotypic changes reflected genetic changes as evidenced by an increase in breeding values for all traits. These changes resulted from selection acting on gamete production and to a lesser extent on courtship display. Selection decreased over years for female gametes, emphasizing the effort of managers to increase the contribution of poor breeders to offspring recruited in the captive breeding. Our results shed light on very fast genetic changes in an exemplary captive programme that follows worldwide used recommendations and emphasizes the need of more empirical evidence of the effects of genetic guidelines on the prevention of genetic changes in supportive breeding