942 research outputs found

    mapping the suitability for ice core drilling of glaciers in the european alps and the asian high mountains

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    ABSTRACTIce cores from mid-latitude mountain glaciers provide detailed information on past climate conditions and regional environmental changes, which is essential for placing current climate change into a longer term perspective. In this context, it is important to define guidelines and create dedicated maps to identify suitable areas for future ice-core drillings. In this study, the suitability for ice-core drilling (SICD) of a mountain glacier is defined as the possibility of extracting an ice core with preserved stratigraphy suitable for reconstructing past climate. Morphometric and climatic variables related to SICD are selected through literature review and characterization of previously drilled sites. A quantitative Weight of Evidence method is proposed to combine selected variables (i.e. slope, local relief, temperature and direct solar radiation) to map the potential drilling sites in mid-latitude mountain glaciers. The method was first developed in the European Alps and then applied to the Asian High Mountains. Model performances and limitations are discussed and first indications of new potential drilling sites in the Asian High Mountains are provided. Results presented here can facilitate the selection of future drilling sites especially on unexplored Asian mountain glaciers towards the understanding of climate and environmental changes

    Effects of secukinumab on serum adipocytokines: preliminary data

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    Psoriatic arthritis (PsA) is a chronic inflammatory disease that affects joints, connective tissues and the axial skeleton. Metabolic syndrome is an independent risk factor for psoriasis (Pso) development and is associated with more severe forms of Pso. Adipocytokines are secreted by white adipose tissue and are thought to link obesity with the development of metabolic and cardiovascular diseases. Secukinumab is a new monoclonal antibody with a different mechanism of action. This antibody selectively binds to and neutralizes interleukin-17 (IL-17) and it has shown efficacy in the treatment of PsA. The aim of this study was to evaluate the possible interferences of secukinumab on different adipocytokines. We enrolled 28 patients with PsA, classified with the CASPAR criteria. Serum samples were stored at baseline and then at the first, the third and the sixth month of therapy. Resistin, chemerin, adiponectin and C-reactive protein (CRP) were dosed. When tested globally, none of the adipokine tested showed any statistically significant variation. However, when the male group was tested, both resistin and chemerin at M6 showed a significant decrease from baseline. CRP did not show any variation at any time point. Our study demonstrated that treatment with secukinumab has little influence on the levels of adipokines tested within the first six months of treatment even though it might exert different influence between males and females from a metabolic perspective. Further studies with greater numbers of patients are needed to determine whether these preliminary results have clinical relevance

    Mapping surface features of an Alpine glacier through multispectral and thermal drone surveys

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    Glacier surfaces are highly heterogeneous mixtures of ice, snow, light-absorbing impurities and debris material. The spatial and temporal variability of these components affects ice surface characteristics and strongly influences glacier energy and mass balance. Remote sensing offers a unique opportunity to characterize glacier optical and thermal properties, enabling a better understanding of different processes occurring at the glacial surface. In this study, we evaluate the potential of optical and thermal data collected from field and drone platforms to map the abundances of predominant glacier surfaces (i.e., snow, clean ice, melting ice, dark ice, cryoconite, dusty snow and debris cover) on the Zebrù glacier in the Italian Alps. The drone surveys were conducted on the ablation zone of the glacier on 29 and 30 July 2020, corresponding to the middle of the ablation season. We identified very high heterogeneity of surface types dominated by melting ice (30% of the investigated area), dark ice (24%), clean ice (19%) and debris cover (17%). The surface temperature of debris cover was inversely related to debris-cover thickness. This relation is influenced by the petrology of debris cover, suggesting the importance of lithology when considering the role of debris over glaciers. Multispectral and thermal drone surveys can thus provide accurate high-resolution maps of different snow and ice types and their temperature, which are critical elements to better understand the glacier’s energy budget and melt rates

    Impact of impurities and cryoconite on the optical properties of the Morteratsch Glacier (Swiss Alps)

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    Abstract. The amount of reflected energy by snow and ice plays a fundamental role in their melting processes. Different non-ice materials (carbonaceous particles, mineral dust (MD), microorganisms, algae, etc.) can decrease the reflectance of snow and ice promoting the melt. The object of this paper is to assess the capability of field and satellite (EO-1 Hyperion) hyperspectral data to characterize the impact of light-absorbing impurities (LAIs) on the surface reflectance of ice and snow of the Vadret da Morteratsch, a large valley glacier in the Swiss Alps. The spatial distribution of both narrow-band and broad-band indices derived from Hyperion was analyzed in relation to ice and snow impurities. In situ and laboratory reflectance spectra were acquired to characterize the optical properties of ice and cryoconite samples. The concentrations of elemental carbon (EC), organic carbon (OC) and levoglucosan were also determined to characterize the impurities found in cryoconite. Multi-wavelength absorbance spectra were measured to compare the optical properties of cryoconite samples and local moraine sediments. In situ reflectance spectra showed that the presence of impurities reduced ice reflectance in visible wavelengths by 80–90 %. Satellite data also showed the outcropping of dust during the melting season in the upper parts of the glacier, revealing that seasonal input of atmospheric dust can decrease the reflectance also in the accumulation zone of the glacier. The presence of EC and OC in cryoconite samples suggests a relevant role of carbonaceous and organic material in the darkening of the ablation zone. This darkening effect is added to that caused by fine debris from lateral moraines, which is assumed to represent a large fraction of cryoconite. Possible input of anthropogenic activity cannot be excluded and further research is needed to assess the role of human activities in the darkening process of glaciers observed in recent years

    Prototipo de un sistema de búsqueda de documentos basado en anotado semántico

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    Gran parte del conocimiento presente en las empresas se encuentra almacenado en objetos de conocimiento. Estos objetos deben ser administrados por una plataforma de gestión de conocimiento en su representación original a fin de facilitar su correcto acceso. Para ello, se debe capturar la semántica de su contenido y proveer herramientas para realizar búsquedas inteligentes. En este contexto, se estableció una vinculación entre el CIDISI, la Fundación Sadosky y la empresa Accion Point S.A. para desarrollar una plataforma prototipo que facilite la búsqueda de documentos asociados a los productos que comercializan. Este trabajo describe la experiencia de un proceso de Desarrollo de un Sistema de gestión de documentos basado en una red de ontologías.Sociedad Argentina de Informática e Investigación Operativ

    The assessment of vertebral fractures in elderly women with recent hip fractures: the BREAK Study

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    Summary This study aimed to evaluate the prevalence of vertebral fractures in elderly women with a recent hip fracture. The burden of vertebral fractures expressed by the Spinal Deformity Index (SDI) is more strictly associated with the trochanteric than the cervical localization of hip fracture and may influence short-term functional outcomes. Introduction This study aimed to determine the prevalence and severity of vertebral fractures in elderly women with recent hip fracture and to assess whether the burden of vertebral fractures may be differently associated with trochanteric hip fractures with respect to cervical hip fractures. Methods We studied 689 Italian women aged 60 years or over with a recent low trauma hip fracture and for whom an adequate X-ray evaluation of spine was available. All radiographs were examined centrally for the presence of any vertebral deformities and radiological morphometry was performed. The SDI, which integrates both the number and the severity of fractures, was also calculated. Results Prevalent vertebral fractures were present in 55.7 % of subjects and 95 women (13.7 %) had at least one severe fracture. The women with trochanteric hip fracture showed higher SDI and higher prevalence of diabetes with respect to those with cervical hip fracture, p00.017 and p00.001, respectively. SDI, surgical menopause, family history of fragility fracture, and type2 diabetes mellitus were independently associated with the risk of trochanteric hip fracture. Moreover, a higher SDI was associated with a higher percentage of postsurgery complications (p00.05) and slower recovery (p<0.05). Conclusions Our study suggests that the burden of prevalent vertebral fractures is more strictly associated with the trochanteric than the cervical localisation of hip fracture and that elevated values of SDI negatively influence short term functional outcomes in women with hip fracture

    Functional and usability assessment of a robotic exoskeleton arm to support activities of daily life

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    An assistive device for upper limb support was developed and evaluated in terms of usability, user satisfaction and motor performance on six end-users affected by neuro-motor disorders (three spinal cord injury; one multiple sclerosis; two Friedreich's ataxia). The system consisted of a lightweight 3-degrees-of-freedom robotic exoskeleton arm for weight relief, equipped with electromagnetic brakes. Users could autonomously control the brakes using a USB-button or residual electromyogram activations. The system functionally supported all of the potential users in performing reaching and drinking tasks. For three of them, time, smoothness, straightness and repeatability were also comparable to healthy subjects. An overall high level of usability (system usability score, median value of 90/100) and user satisfaction (Tele-healthcare Satisfaction Questionnaire - Wearable Technology, median value of 104/120) were obtained for all subject

    Sesquiterpene Lactones with Anti-Hepatitis C Virus Activity Using Molecular Descriptors

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    Hepatitis C is a worldwide public health problem. The available therapies are limited by their partial effectiveness and with meaningful side-effects. Sesquiterpene lactones (SLs) are a group of natural products with a wide variety of chemical structures and biological activities associated. There are few studies about the influence of the molecular structure of SLs for the anti-hepatitis C virus activity. In the present work, SLs are investigated in a subgenomic RNA replicon assay system and were analyzed using multiple linear regression along with self-organizing maps with DRAGON descriptors in order to identify the structural requirements for their biological activity and to predict the inhibitory potency of SLs. Characteristics such as stereochemistry and electronic effects demonstrated to be important for their anti-HCV activity, and the SOM produced a clear separation betwenn active and inactive compounds. Therefore, it is possible to use this map as a filter for virtual screening to predict the anti-HCV activity of SLs.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

    MUNDUS project : MUltimodal neuroprosthesis for daily upper limb support

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    Background: MUNDUS is an assistive framework for recovering direct interaction capability of severely motor impaired people based on arm reaching and hand functions. It aims at achieving personalization, modularity and maximization of the user’s direct involvement in assistive systems. To this, MUNDUS exploits any residual control of the end-user and can be adapted to the level of severity or to the progression of the disease allowing the user to voluntarily interact with the environment. MUNDUS target pathologies are high-level spinal cord injury (SCI) and neurodegenerative and genetic neuromuscular diseases, such as amyotrophic lateral sclerosis, Friedreich ataxia, and multiple sclerosis (MS). The system can be alternatively driven by residual voluntary muscular activation, head/eye motion, and brain signals. MUNDUS modularly combines an antigravity lightweight and non-cumbersome exoskeleton, closed-loop controlled Neuromuscular Electrical Stimulation for arm and hand motion, and potentially a motorized hand orthosis, for grasping interactive objects. Methods: The definition of the requirements and of the interaction tasks were designed by a focus group with experts and a questionnaire with 36 potential end-users. Five end-users (3 SCI and 2 MS) tested the system in the configuration suitable to their specific level of impairment. They performed two exemplary tasks: reaching different points in the working volume and drinking. Three experts evaluated over a 3-level score (from 0, unsuccessful, to 2, completely functional) the execution of each assisted sub-action. Results: The functionality of all modules has been successfully demonstrated. User’s intention was detected with a 100% success. Averaging all subjects and tasks, the minimum evaluation score obtained was 1.13 ± 0.99 for the release of the handle during the drinking task, whilst all the other sub-actions achieved a mean value above 1.6. All users, but one, subjectively perceived the usefulness of the assistance and could easily control the system. Donning time ranged from 6 to 65 minutes, scaled on the configuration complexity. Conclusions: The MUNDUS platform provides functional assistance to daily life activities; the modules integration depends on the user’s need, the functionality of the system have been demonstrated for all the possible configurations, and preliminary assessment of usability and acceptance is promising
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