325 research outputs found

    Temporal Adaptive Changes in Contractility and Fatigability of Diaphragm Muscles from Streptozotocin-Diabetic Rats

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    Diabetes is characterized by ventilatory depression due to decreased diaphragm (DPH) function. This study investigated the changes in contractile properties of rat DPH muscles over a time interval encompassing from 4 days to 14 weeks after the onset of streptozotocin-induced diabetes, with and without insulin treatment for 2 weeks. Maximum tetanic force in intact DPH muscle strips and recovery from fatiguing stimulation were measured. An early (4-day) depression in contractile function in diabetic DPH was followed by gradual improvement in muscle function and fatigue recovery (8 weeks). DPH contractile function deteriorated again at 14 weeks, a process that was completely reversed by insulin treatment. Maximal contractile force and calcium sensitivity assessed in Triton-skinned DPH fibers showed a similar bimodal pattern and the same beneficial effect of insulin treatment. While an extensive analysis of the isoforms of the contractile and regulatory proteins was not conducted, Western blot analysis of tropomyosin suggests that the changes in diabetic DPH response depended, at least in part, on a switch in fiber type

    Experimental confirmation of the low B isotope coefficient in MgB2

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    Recent investigations have shown that the first proposed explanations of the disagreement between experimental and theoretical value of isotope coefficient in MgB2 need to be reconsidered. Considering that in samples with residual resistivity of few mu-Ohm cm critical temperature variations produced by disorder effects can be comparable with variations due to the isotopic effect, we adopt a procedure in evaluating the B isotope coefficient which take account of these effects, obtaining a value which is in agreement with previous results and then confirming that there is something still unclear in the physics of MgB2.Comment: 8 pages, 3 figures Title has been changed A statement has been added in page 7 of the pdf file "Finally we would..." Reference 21 has been added Figure 1 anf Figure 2 have been change

    Certifying forest-based ecosystem services: results from the world-first application of the FSC ecosystem service procedure in Italy

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    In recent years, several mechanisms have been put in practice to value forest-based ecosystem services in order to maintain or enhance their provision. Mechanisms range from more traditional - e.g. regulation of land use, taxes and subsidies - to more innovative market-based ones such as Payments for Ecosystem Services (PES). More recently, the use of voluntary third-party forest certification schemes based on standards and procedures specifically aimed at considering the provision of ecosystem services has gained interests. Certification schemes have already been established for specific ecosystem services, in particular focusing on carbon, in some cases including biodiversity conservation as a co-benefit. The Forest Stewardship Council\uae (FSC) is currently the only scheme promoting the certification of multiple ecosystem services by demonstrating the positive impacts of FSC-certified forest management practices on five regulating and cultural services. A dedicated procedure has been developed, that allows the assessment of the impact of forest management on carbon sequestration and storage, biodiversity conservation, watershed services, soil conservation and recreational services, by means of specific methodologies and indicators. We critically analyzed the world-first application of the FSC ecosystem services certification procedure with reference to the forest certification group Waldplus and Associazione Forestale di Pianura (Lowland Forest Association) in northern Italy. The case study includes 1,043 hectares of different forest types, from semi-natural productive forests to conservation forests, traditionally managed to deliver multiple benefits. Our objective is to give insights that could inform and improve future developments in the field of certification, promotion and marketing of ecosystem services

    Intraband versus interband scattering rate effects in neutron irradiated MgB2

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    One of the most important predictions of the two-gap theory of superconductivity concerns the role of interband scattering (IBS) by impurities. IBS is expected to decrease the critical temperature, Tc, of MgB2 to a saturation value of about 20 K, where the two gaps merge to a single one. These predictions have been partially contradicted by experiments. In fact, Tc does not saturate in irradiated samples, but decreases linearly with residual resistivity and the merging of the gaps has been observed at a much lower Tc (11 K). In this paper we argue that, while at low level of disorder IBS is the leading mechanism that suppresses superconductivity, at higher disorder the experimental results can only be understood if the smearing of the density of states due to intraband electron lifetime effects is considered.Comment: 3 figure

    Sindbad: A new operational service for a safer leisure and boating navigation

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    The SINDBAD- Leisure and Boating Safety Navigation - project goal is the development of an advanced operational service to support navigation in a specific area. The first prototype covers the Ligurian Sea (a very busy touristic area in the North Mediterranean Sea) It develops an ICT Service Infrastructure to provide innovative intelligent automation functions and to develop customized services, accessible by your mobile device, for conducting a boat and avoiding any kind of risk ensuring the best degree of comfort

    Nonequilibrium superconducting thin films with sub-gap and pair-breaking photon illumination

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    We calculate nonequilibrium quasiparticle and phonon distributions for a number of widely-used low transition temperature thin-film superconductors under constant, uniform illumination by sub-gap probe and pair-breaking signal photons simultaneously. From these distributions we calculate material-characteristic parameters that allow rapid evaluation of an effective quasiparticle temperature using a simple analytical expression, for all materials studied (Mo, Al, Ta, Nb, and NbN) for all photon energies. We also explore the temperature and energy-dependence of the low-energy quasiparticle generation efficiency η\eta by pair-breaking signal photons finding η0.6\eta \approx 0.6 in the limit of thick films at low bath temperatures that is material-independent. Taking the energy distribution of excess quasiparticles into account, we find η1\eta \to 1 as the bath temperature approaches the transition temperature in agreement with the assumption of the two-temperature model of the nonequilibrium response that is appropriate in that regime. The behaviour of η\eta with signal frequency scaled by the superconducting energy gap is also shown to be material-independent, and is in qualitative agreement with recent experimental results. An enhancement of η\eta in the presence of sub-gap (probe) photons is shown to be most significant at signal frequencies near the superconducting gap frequency and arises due to multiple photon absorption events that increase the average energy of excess quasiparticles above that in the absence of the probe.This is the author accepted manuscript. The final version is available via IOP Science at http://iopscience.iop.org/0953-2048/28/5/054002/

    Correspondence Between Cognitive and Audiological Evaluations Among the Elderly: A Preliminary Report of an Audiological Screening Model of Subjects at Risk of Cognitive Decline With Slight to Moderate Hearing Loss

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    Epidemiological studies show increasing prevalence rates of cognitive decline and hearing loss with age, particularly after the age of 65 years. These conditions are reported to be associated, although conclusive evidence of causality and implications is lacking. Nevertheless, audiological and cognitive assessment among elderly people is a key target for comprehensive and multidisciplinary evaluation of the subject's frailty status. To evaluate the use of tools for identifying older adults at risk of hearing loss and cognitive decline and to compare skills and abilities in terms of hearing and cognitive performances between older adults and young subjects, we performed a prospective cross-sectional study using supraliminal auditory tests. The relationship between cognitive assessment results and audiometric results was investigated, and reference ranges for different ages or stages of disease were determined. Patients older than 65 years with different degrees of hearing function were enrolled. Each subject underwent an extensive audiological assessment, including tonal and speech audiometry, Italian Matrix Sentence Test, and speech audiometry with logatomes in quiet. Cognitive function was screened and then verified by experienced clinicians using the Montreal Cognitive Assessment Score, the Geriatric Depression Scale, and further investigations in some. One hundred twenty-three subjects were finally enrolled during 2016-2019: 103 were >65 years of age and 20 were younger participants (as controls). Cognitive functions showed a correlation with the audiological results in post-lingual hearing-impaired patients, in particular in those affected by slight to moderate hearing loss and aged more than 70 years. Audiological testing can thus be useful in clinical assessment and identification of patients at risk of cognitive impairment. The study was limited by its sample size (CI 95%; CL 10%), strict dependence on language, and hearing threshold. Further investigations should be conducted to confirm the reported results and to verify similar screening models
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