215 research outputs found

    Birds use individually consistent temperature cues to time their migration departure

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    A fundamental question in migration biology is how birds decide when to start their journey, given that arriving too early or too late in a variable environment reduces individual fitness. Internal circannual regulation, and predictable cues such as photoperiod, prepare birds for migration, while variable external cues such as temperature and wind are thought to fine-tune departure times; however, this has not been demonstrated at the key point where an individual animal decides to start its migration. In theory, environmental cues correlated between departure and arrival sites allow informed departure decisions. For 48 satellite-tracked Asian houbara Chlamydotis macqueenii, a medium-distance migrant with climatic connectivity between wintering and breeding areas, each tracked across multiple years, spring departure was under individually-consistent temperature conditions, with greater individual repeatability than for photoperiod or wind. Individuals occupied a range of wintering sites latitudinally spanning 1,200 km, but departed from more northerly latitudes at lower temperatures. These individual departure decisions produced earlier mean population-level departure and arrival dates in warmer springs. Phenological adjustments were fully compensatory, as individuals arrived on the breeding grounds under similar temperature conditions each year. Individuals’ autumn departure decisions were also highly repeatable relative to temperature, but were less distinct than for spring, likely due to relaxed time constraints to leave breeding grounds or reach wintering sites, and use of autumn wind as a supplementary departure cue. Here we have shown that individual-level departure decisions informed by local temperatures can pre-adapt a population to adjust its population-level phenology in response to annual variability in springs timings without genetic change in reaction thresholds

    Botulism Type E Outbreak Associated with Eating a Beached Whale, Alaska

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    We report an outbreak of botulism that occurred in July 2002 in a group of 12 Alaskan Yu'pik Eskimos who ate blubber and skin from a beached beluga whale. Botulism death rates among Alaska Natives have declined in the last 20 years, yet incidence has increased

    Placement, survival and predator identity of Eurasian Curlew Numenius arquata nests on lowland grass-heath

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    Capsule: Within the UK’s largest lowland Eurasian Curlew Numenius arquata population, curlew preferentially nested on physically disturbed (treated) than undisturbed (control) grassland, and low nest survival rates were primarily attributable to predation by Red Fox Vulpes vulpes. Aims: To inform conservation interventions for Curlew within semi-natural lowland dry-grassland landscapes. Methods: Across a 3700 ha lowland dry-grassland landscape, over two years, effects of ground-disturbance management on Curlew nest placement (n = 41) were examined using generalized linear models controlling for vegetation strata. The effects of site and management on nest survival (n = 44) were also examined, controlling for lay date and year. Nest predator identity was investigated using temperature sensors (n = 28) and nest cameras (n = 10). Results: Curlews were five times more likely to nest on physically disturbed than undisturbed grassland. Nest survival (overall mean ± se = 0.24 ± 0.07) was not influenced by year or ground-disturbance but declined with lay date and differed markedly between the two sites, consistent with predator control. Predation accounted for 29/32 failed nests and was predominantly at night (17/23 cases where timing was known), consistent with mammalian predators. Cameras indicated Red Foxes to be the main predator (4/5 cases). Overall breeding productivity was 0.16 ± 0.01 (SE) chicks per nesting attempt. Conclusion: Curlew suffered from unsustainably high rates of nest predation primarily attributable to Red Foxes. A combination of perimeter fencing and lethal predator control appeared to improve nest success at one site. Ground-disturbance treatment could encourage nesting attempts in areas managed to minimize predator density

    Ursinus College Alumni Journal, March 1964

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    Standing room only ‱ New student facilities building ‱ Campaign receipts reach $285,765 at mid-March ‱ Matching gifts ‱ Mid-year report of 1964 Loyalty Fund campaign ‱ Income while you live . . . benefaction when you die ‱ Cutting campus ‱ John Fitzgerald Kennedy ‱ Eccentricities of our political life ‱ A bitter dramatic example ‱ Crisis of conscience in Dallas ‱ Student reaction to November 22-25 ‱ Two recipients for 1964 alumni award ‱ The class of 1911 ‱ The alumni album: C. Richard Snyder, \u2729; William D. Reimert, \u2724; Wainright E. H. Diehl, \u2751; Marguerite Goldthwaite Godshall, \u2732; Franklin E. Morris, \u2741; J. William Ditter, Jr., \u2743; Robert Poole, III, \u2750; Bain and Edwards\u27 sons: football foes ‱ Nominees for alumni association offices ‱ Class notes ‱ Weddings ‱ Births ‱ Necrology ‱ Regionalshttps://digitalcommons.ursinus.edu/alumnijournal/1079/thumbnail.jp

    T1DBase: integration and presentation of complex data for type 1 diabetes research

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    T1DBase () [Smink et al. (2005) Nucleic Acids Res., 33, D544–D549; Burren et al. (2004) Hum. Genomics, 1, 98–109] is a public website and database that supports the type 1 diabetes (T1D) research community. T1DBase provides a consolidated T1D-oriented view of the complex data world that now confronts medical researchers and enables scientists to navigate from information they know to information that is new to them. Overview pages for genes and markers summarize information for these elements. The Gene Dossier summarizes information for a list of genes. GBrowse [Stein et al. (2002) Genome Res., 10, 1599–1610] displays genes and other features in their genomic context, and Cytoscape [Shannon et al. (2003) Genome Res., 13, 2498–2504] shows genes in the context of interacting proteins and genes. The Beta Cell Gene Atlas shows gene expression in ÎČ cells, islets, and related cell types and lines, and the Tissue Expression Viewer shows expression across other tissues. The Microarray Viewer shows expression from more than 20 array experiments. The Beta Cell Gene Expression Bank contains manually curated gene and pathway annotations for genes expressed in ÎČ cells. T1DMart is a query tool for markers and genotypes. PosterPages are ‘home pages’ about specific topics or datasets. The key challenge, now and in the future, is to provide powerful informatics capabilities to T1D scientists in a form they can use to enhance their research

    Heat stored in the Earth system 1960–2020: where does the energy go?

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    The Earth climate system is out of energy balance, and heat has accumulated continuously over the past decades, warming the ocean, the land, the cryosphere, and the atmosphere. According to the Sixth Assessment Report by Working Group I of the Intergovernmental Panel on Climate Change, this planetary warming over multiple decades is human-driven and results in unprecedented and committed changes to the Earth system, with adverse impacts for ecosystems and human systems. The Earth heat inventory provides a measure of the Earth energy imbalance (EEI) and allows for quantifying how much heat has accumulated in the Earth system, as well as where the heat is stored. Here we show that the Earth system has continued to accumulate heat, with 381±61 ZJ accumulated from 1971 to 2020. This is equivalent to a heating rate (i.e., the EEI) of 0.48±0.1 W m−2. The majority, about 89 %, of this heat is stored in the ocean, followed by about 6 % on land, 1 % in the atmosphere, and about 4 % available for melting the cryosphere. Over the most recent period (2006–2020), the EEI amounts to 0.76±0.2 W m−2. The Earth energy imbalance is the most fundamental global climate indicator that the scientific community and the public can use as the measure of how well the world is doing in the task of bringing anthropogenic climate change under control. Moreover, this indicator is highly complementary to other established ones like global mean surface temperature as it represents a robust measure of the rate of climate change and its future commitment. We call for an implementation of the Earth energy imbalance into the Paris Agreement's Global Stocktake based on best available science. The Earth heat inventory in this study, updated from von Schuckmann et al. (2020), is underpinned by worldwide multidisciplinary collaboration and demonstrates the critical importance of concerted international efforts for climate change monitoring and community-based recommendations and we also call for urgently needed actions for enabling continuity, archiving, rescuing, and calibrating efforts to assure improved and long-term monitoring capacity of the global climate observing system. The data for the Earth heat inventory are publicly available, and more details are provided in Table 4

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
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