197 research outputs found

    Expansion of magnetic clouds in the outer heliosphere

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    A large amount of magnetized plasma is frequently ejected from the Sun as coronal mass ejections (CMEs). Some of these ejections are detected in the solar wind as magnetic clouds (MCs) that have flux rope signatures. Magnetic clouds are structures that typically expand in the inner heliosphere. We derive the expansion properties of MCs in the outer heliosphere from one to five astronomical units to compare them with those in the inner heliosphere. We analyze MCs observed by the Ulysses spacecraft using insitu magnetic field and plasma measurements. The MC boundaries are defined in the MC frame after defining the MC axis with a minimum variance method applied only to the flux rope structure. As in the inner heliosphere, a large fraction of the velocity profile within MCs is close to a linear function of time. This is indicative of} a self-similar expansion and a MC size that locally follows a power-law of the solar distance with an exponent called zeta. We derive the value of zeta from the insitu velocity data. We analyze separately the non-perturbed MCs (cases showing a linear velocity profile almost for the full event), and perturbed MCs (cases showing a strongly distorted velocity profile). We find that non-perturbed MCs expand with a similar non-dimensional expansion rate (zeta=1.05+-0.34), i.e. slightly faster than at the solar distance and in the inner heliosphere (zeta=0.91+-0.23). The subset of perturbed MCs expands, as in the inner heliosphere, at a significantly lower rate and with a larger dispersion (zeta=0.28+-0.52) as expected from the temporal evolution found in numerical simulations. This local measure of the expansion also agrees with the distribution with distance of MC size,mean magnetic field, and plasma parameters. The MCs interacting with a strong field region, e.g. another MC, have the most variable expansion rate (ranging from compression to over-expansion)

    Role of angiotensin-converting enzyme and vitamin D receptor gene polymorphisms in cancer anorexia-cachexia syndrome

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    The ubiquitin-proteasome pathway is a crucial connection between aberrant immune system activation, systemic inflammation and Cancer Anorexia-Cachexia Syndrome (CACS), a syndrome that culminates in hyper-activation of the ubiquitin-proteasome pathway. Angiotensin directly up-regulates this pathway, while vitamin D down-regulates it indirectly through the insulin-like growth factor-1 pathway. We investigated the genetic predisposition towards CACS in a cancer population, examining Insertion/Deletion (I/D) polymorphism of angiotensin-converting enzyme gene and FokI and BsmI polymorphisms of vitamin D receptor gene. Sixty-two cancer patients were recruited and divided into three groups: primary cachectic (C1, n = 14; dysmetabolic body weight loss ≥5% in 6 months); secondary cachectic (C2, n = 34; similar weight loss, mechanic or iatrogenic origin); and non-cachectic (NC, n = 16). C2+NC were merged in the control group. The three groups showed significant differences in average prognostic inflammatory nutritional index (C1: 26.4±23.4; C2: 5.4±5.6; NC: 0.37±0.5), C-reactive protein serum levels (C1: 6.6±2.1; C2: 2.4±2.2; NC: 1.0±2.0 mg/dL), albumin serum levels (C1: 3.1±0.6; C2: 3.5±0.4; NC 3.7±0.6 g/dL), weight loss (C1: 22±8; C2: 15±6.7; NC 5±6%) and life expectancy (C1: 6.4±3.3; C2: 25±28; NC: 45±25 months). However, none of the chosen polymorphisms showed any statistically significant correlation with CACS. The complexity of the changes of the immune system in the chronic inflammation state associated with CACS is far greater than expected and further studies are required to identify genetic independent markers of progression toward CACS.

    Low-Cost Heaving Single-Buoy Wave-Energy Point Absorber Optimization for Sardinia West Coast

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    This work presents the Water Energy Point Absorber (WEPA), which is a heaving single-buoy point absorber optimized for a specific site off the west coast of Sardinia Island. The aim of the study is to present the optimization process undertaken to identify the best configuration in terms of performance and cost. The optimization is carried out thanks to a simulation tool developed in Matlab-Simulink environment and verified through to the commercial software Orcaflex. Simulations are performed in the time domain with the installation site’s waves as input. The hydrodynamics parameters are computed thanks to the commercial software Ansys Aqwa and given to the model as input. The yearly energy production is computed as output for each configuration. Several parametric analyses are performed to identify the optimal Power Take Off (PTO) and buoy size. Among the main findings, it shall be mentioned that the PTO-rated torque has a strong influence on the energy production, higher PTO-rated torque proved to have better performance. The optimal hull size is strictly related to the incoming waves, and for the given site the smaller hulls are performing better than larger ones. The hull height, hull mass and hull draft have little impact on productivity. Finally, a comprehensive techno–economic analysis is performed, showing that the best configuration can be identified only after a detailed feasibility study and rigorous cost analysis

    Phase II study of lonidamine in metastatic breast cancer.

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    Thirty patients with previously treated metastatic breast cancer were entered in a phase II study with oral lonidamine. Twenty-eight patients are evaluable for toxicity and 25 for response. A partial remission was obtained in four patients (16%) and disease stability in 11 (44%): 10 patients progressed (40%). Toxicity was acceptable, consisting mainly of myalgias (39% of patients) and asthenia (21.4%). No myelotoxicity was observed. The drug is active in previously treated metastatic breast cancer and, because of its peculiar pattern of action and toxicity, deserves to be evaluated in combination with cytotoxic chemotherapy

    Intrusion Detection in Industrial Networks via Data Streaming

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    Given the increasing threat surface of industrial networks due to distributed, Internet-of-Things (IoT) based system architectures, detecting intrusions in\ua0 Industrial IoT (IIoT) systems is all the more important, due to the safety implications of potential threats. The continuously generated data in such systems form both a challenge but also a possibility: data volumes/rates are high and require processing and communication capacity but they contain information useful for system operation and for detection of unwanted situations.In this chapter we explain that\ua0 stream processing (a.k.a. data streaming) is an emerging useful approach both for general applications and for intrusion detection in particular, especially since it can enable data analysis to be carried out in the continuum of edge-fog-cloud distributed architectures of industrial networks, thus reducing communication latency and gradually filtering and aggregating data volumes. We argue that usefulness stems also due to\ua0 facilitating provisioning of agile responses, i.e. due to potentially smaller latency for intrusion detection and hence also improved possibilities for intrusion mitigation. In the chapter we outline architectural features of IIoT networks, potential threats and examples of state-of-the art intrusion detection methodologies. Moreover, we give an overview of how leveraging distributed and parallel execution of streaming applications in industrial setups can influence the possibilities of protecting these systems. In these contexts, we give examples using electricity networks (a.k.a. Smart Grid systems).We conclude that future industrial networks, especially their Intrusion Detection Systems (IDSs), should take advantage of data streaming concept by decoupling semantics from the deployment

    Meta-analysis of genes in commercially available nutrigenomic tests denotes lack of association with dietary intake and nutrient-related pathologies

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    Nutrigenomics is an emerging discipline that aims to investigate how individual genetic composition correlates with dietary intake, as well as how nutrition influences gene expression. Herein, the fundamental question relates to the value of nutrigenomics testing on the basis of the currently available scientific evidence. A thorough literature search has been conducted in PubMed scientific literature database for nutrigenomics research studies on 38 genes included in nutrigenomics tests provided by various private genetic testing laboratories. Data were subsequently meta-analyzed to identify possible associations between the genes of interest and dietary intake and/or nutrient-related pathologies. Data analysis occurred according to four different models due to data sparsity and inconsistency. Data from 524,592 individuals (361,153 cases and 163,439 controls) in a total of 1,170 entries were obtained. Conflicting findings indicated that there was a great incompatibility regarding the associations (or their absence) identified. No specific-and statistically significant-association was identified for any of the 38 genes of interest. In those cases, where a weak association was demonstrated, evidence was based on a limited number of studies. As solid scientific evidence is currently lacking, commercially available nutrigenomics tests cannot be presently recommended. Notwithstanding, the need for a thorough and continuous nutrigenomics research is evident as it is a highly promising tool towards precision medicine

    Antagonizing α7 nicotinic receptors with methyllycaconitine (MLA) potentiates receptor activity and memory acquisition

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    Abstract α7 nicotinic acetylcholine receptors (α7nAChRs) have been targeted to improve cognition in different neurological and psychiatric disorders. Nevertheless, no α7nAChR activating ligand has been clinically approved. Here, we investigated the effects of antagonizing α7nAChRs using the selective antagonist methyllycaconitine (MLA) on receptor activity in vitro and cognitive functioning in vivo. Picomolar concentrations of MLA significantly potentiated receptor responses in electrophysiological experiments mimicking the in vivo situation. Furthermore, microdialysis studies showed that MLA administration substantially increased hippocampal glutamate efflux which is related to memory processes. Accordingly, pre-tetanus administration of low MLA concentrations produced longer lasting potentiation (long-term potentiation, LTP) in studies examining hippocampal plasticity. Moreover, low doses of MLA improved acquisition, but not consolidation memory processes in rats. While the focus to enhance cognition by modulating α7nAChRs lies on agonists and positive modulators, antagonists at low doses should provide a novel approach to improve cognition in neurological and psychiatric disorders

    The Cerebellar Dopaminergic System

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    In the central nervous system (CNS), dopamine (DA) is involved in motor and cognitive functions. Although the cerebellum is not been considered an elective dopaminergic region, studies attributed to it a critical role in dopamine deficit-related neurological and psychiatric disorders [e.g., Parkinson's disease (PD) and schizophrenia (SCZ)]. Data on the cerebellar dopaminergic neuronal system are still lacking. Nevertheless, biochemical studies detected in the mammalians cerebellum high dopamine levels, while chemical neuroanatomy studies revealed the presence of midbrain dopaminergic afferents to the cerebellum as well as wide distribution of the dopaminergic receptor subtypes (DRD1-DRD5). The present review summarizes the data on the cerebellar dopaminergic system including its involvement in associative and projective circuits. Furthermore, this study also briefly discusses the role of the cerebellar dopaminergic system in some neurologic and psychiatric disorders and suggests its potential involvement as a target in pharmacologic and non-pharmacologic treatments
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