203 research outputs found

    Climate, abiotic factors, and the evolution of subterranean life

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    Climate, and more generally the physical conditions in caves and other subterranean habitats have a profound influence on the biota. At longer time scale (centuries), climate change can force and/or isolate species in subterranean habitats. Not only Pleistocene climate changes, but earlier ones as well, suchas the Messinian salinity crisis were important in this regard. While many speleobiologists assume that caves are nearly constant environmentally and withscarce organic carbon, this is not the case, especially in non-cave subterranean habitats. Many shal­low subterranean habitats, suchas epikarst, seepage springs, and talus harbor highly modified organisms, ones without eyes and pigment and withelongated appendages. Yet these habi­tats are highly variable withrespect to temperature and other environmental factors, and often have highlevels of organic carbon. Overall, the role of these shallow subterranean habitats in the evolution and biogeography of subterranean species may be crucial. On smaller spatial scales, environmental differences, suchas differences in chemistry of epikarst water, may be im­portant in allowing large numbers of species to coexist

    Organic Carbon in Shallow Subterranean Habitats

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    subterranean habitatsOrganic carbon is likely to be a limiting factor in shallow subterranean habitats (SSHs). Data on dissolved organic carbon (DOC) in three SSHs are reviewed: (1) hypotelminorheic and associated seepage springs (Nanos Mountain, Slovenia), (2) hyporheic zones (Rhône River, France and seepage streams on Nanos Mountain, Slovenia), and (3) epikarst (China, Slovenia, and USA). Hypotelminorheic habitats are superficial groundwater sites less than 1 m below the surface that exit from seepage springs. Hyporheic habitats are the underflow of streams and rivers. Epikarst is the uppermost zone of karst with extensive small cavities and channels. Nanos hypotelminorheic sites that harbored stygobiotic species had organic carbon values averaging 3.4 mg C L−1, and temporal variability was high. For hypoheic sites in the Rhône River basin and on Nanos Mountain, mean values ranged from 1.4 to 3.5 mg C L−1. In the more extensively studied Rhône River basin sites, temporal variability was low. Epikarst DOC ranged from 0.70 to 1.10 mg C L−1 in three caves in China (Shihua Cave), Slovenia (Postojna Planina Cave System) and United States (Organ Cave, West Virginia). These results suggest that organic carbon in aquatic SSHs is lowest in epikarst.Keywords: dissolved organic carbon, epikarst, hyporheic, hypotelminorheic, seepage spring.DOI: 10.3986/ac.v42i2.60

    What Does the Distribution of Stygobiotic Copepoda (Crustacea) Tell Us About Their Age?

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    Geographic distribution of stygobionts is often used to estimate age of a group by assuming vicariant speciation with little or no subsequent dispersal. We investigated the utility of using distributional data for Slovenian stygobiotic copepods by assuming that dispersal is a way to measure age of a species. We list some species of Copepoda that, on the basis of their range and frequency of occupancy within their range, should be older. Body size is not predictor either of range or frequency of occupancy

    Influenza molecular diagnostic testing in a 1000-bed academic Italian hospital during the 2018\u201319 influenza season

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    Aim: The aims of this study were to examine the requests for influenza molecular tests processed by the Virology Laboratory of the University Hospital of Udine during the 2018\u201319 influenza season and to assess the test results and to estimate costs. Subjects and methods: We analyzed various administrative databases of the hospital health information system, which can be deterministically linked at the individual level through an anonymous stochastic key. Requests for influenza molecular tests from November 1, 2018, to April 15, 2019, and test results were described by week and, for hospitalized patients, hospital ward. Previous vaccination status of tested patients, outcomes and estimated test costs were assessed. Results: In the 2018\u201319 influenza season, 979 influenza A and B virologic tests were processed by the laboratory, corresponding to 758 patients. Requests had more than doubled compared with the previous influenza season. Rapid real-time PCR tests, routinely available at the University Hospital of Udine since January 2019, represented 17% of requests. Six hundred forty-eight patients were hospitalized. Medical wards requested the test after a median of 1 day after admission, whereas requests were delayed for surgical and oncologic patients. The number of tests, proportion of positivity and consumption of rapid tests varied by medical specialty. Overall consumption of oseltamivir was similar to that of the previous influenza season. Conclusions: This analysis, benefiting from the availability of integrated health administrative databases, provided useful information to support public health decision-making and managing the supply and demand for diagnostic tests

    Morphological Differences Among Eyeless Amphipods in the Genus Stygobromus Dwelling in Different Subterranean Habitats

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    The amphipod genus Stygobromus occurs in a variety of subterranean habitats in North America, including caves, phreatic (groundwater) lakes, and superficial subterranean habitats (seeps and epikarst). The habitats share the absence of light but differ in other features, such as pore size of the habitat, available food, and degree of seasonality. Measurements of body size, antennal size, and antennal segment number of type specimens were compared for 56 species occurring in the eastern United States. Except for differences in body size, differences among species in the four different habitats were not significant. Body size was related to relative pore size of the habitat, e.g., epikarst, with the smallest spaces, had the smallest species. However, in all habitats, there was one very large species (\u3e 15mm); these enigmatic species apparently occupy a distinct ecological niche, perhaps being more predatory. Differences in relative antennal size showed no significant differences among habitats, and differences in number of antennal segments were marginally significant (P = 0.06) among habitat types and not in the predicted pattern. Differences among habitats in seasonality and available food seemed to be a minor part of the selective environment; absence of light seemed to be a major part of the selective environment

    Fifty Years of the Hypotelminorheic: What Have We Learned?

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    Originally described by Meštrov in 1962, hypotelminorheic habitats are superficial subterranean drainages, typically less than a meter or so in depth, that emerge at small seepage springs. These are persistent wet spots, typically with blackened leaves in small depressions. There may be no flow during dry periods, but the underlying clay retains water above. They share the landscape with other small bodies of water (močila in Slovenian), not necessarily connected with groundwater. Hypotelminorheic habitats (mezišča in Slovenian) usually harbor a fauna dominated by species adapted to subterranean life, characteristically without eyes or pigment. The basic chemistry and hydrology of the habitat is described as are the basic faunal elements. The habitat is placed in a more general context by reviewing how species invade the habitat, their morphology, and their possible connection to deeper subterranean habitats

    Curriculum and collective consciousness : speculations on individualism, community and cosmos

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    This study joins the work of a number of contemporary curriculum theorists who are attempting to foster a "language of possibility" for education. The impetus for this study is derived from, and the first chapter addresses, the paradoxical modernist situation where both increasing technological innovation and individualist approaches to development and competence have resulted in a world poised on the brink of catastrophic nuclear war and social disintegration, alienation. This study, then, examines the emergence of modernist, technical rationality; social, political and philosophical frameworks which situate this present historical moment in incommensurable paradigms; and the curricular implications of modernist culture. Curriculum theory, as it is approached in this study, is portrayed as an interpretative science - a critical and expressive endeavor which attempts to promote human understanding and meaningful action in both practical and liberative intents. The second chapter draws upon the recent re-emergence of philosophical hermeneutics as not only a research methodology, but as a sophisticated and systematic interpretation of the normative dimensions of human interests and knowledge

    The harmony of conflict : the cosmology of Heracleitus in D. H. Lawrence's Women in love

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    It was the purpose of this study to relate the world view expressed within Women in Love to a cosmological order devised by the Greek philosopher Heracleitus as expressed in his work "On Nature." Women in Love contains a plethora of bipolar dichotomies which often reveal a world of conflict, tension and oscillating change. When the Heracleitian world order is superimposed on the conflicting forces operating in Lawrence's novel, an underlying unity or logos becomes apparent. Lawrence's strong affinity with Heracleltus' cosmology is traced throughout Women in Love and other selections from his writing. Lawrence's Intentional air of mysticism and choric suggestivity are compared to Heracleltus' oracular, often ambiguous statements. Both Lawrence and Heracleltus share perceptions of a dual plane of experience: one of the phenomenal world of physical, material forces and a second of noumenal, transcendental communion

    The burden of severe cases of Influenza disease: The Friuli Venezia Giulia Region experience

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    IIntroduction. Influenza is a matter of serious concern for clinicians, in both outpatient and in-hospital settings. Worldwide, the 2017-18 epidemic proved to be the most severe since 2003-04. We report a real-world experience regarding the management of patients with influenza admitted to a large teaching hospital in the Friuli Venezia Giulia region during the 2017-2018 influenza season. We also provide a practical guide for the management of hospitalized influenza patients. Methods. A retrospective observational analysis was conducted among all influenza patients requiring admission to our center during the 2017-18 season. Results. Overall, 29 patients were admitted to the University Hospital of Udine during the 2017-18 season with a diagnosis of influenza. B virus was responsible for the majority of cases. More than 65.5% of the subjects presented with a complication. We estimated that 41.4% of the patients admitted were affected by a \u201csevere form\u201d. All these cases required admission to the Intensive Care Unit, with 27.6% and 10.3% needing Orotracheal Intubation and Extracorporeal Membrane Oxygenation, respectively. The fatality rate was 24.1%. Notably, only 9 subjects in our cohort had been vaccinated. Based on the experience acquired during the past season, we propose a practical guide to the management of influenza cases in everyday hospital practice. Conclusion. The cornerstones of the management of all hospitalized influenza patients are the rapid identification and treatment of severe forms. Timely and strict adherence to contact and respiratory precautions are also fundamental to reducing the risk of intra-hospital outbreaks. Despite improvements in antiviral therapies and supportive measures, influenza-related morbidity and mortality remain high. In our opinion, a universal vaccination program is the only safe and effective method of filling the gap
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