2,027 research outputs found
Application of Metamaterials for Multifunctional Satellite Bus Enabled via Additive Manufacturing
Space systems require materials with superior stiffness to weight ratios to provide structural integrity while minimizing mass. Additive manufacturing processes enable the design of metamaterials that exceed the performance of naturally occurring materials in addition to allowing the integration of non-structural functions. This research explored the use of a high stiffness, high density, small melt pool track width AM material, Inconel 718, to enable the production of metamaterials with finer features possible than can possibly be created using a lower density aluminum alloy material. Various metamaterials were designed utilizing thin wall triply periodic minimal surface infilled sandwich structures. The performance characteristics of these metamaterials were evaluated through modal analysis; demonstrating a 16-18% greater stiffness-to-weight ratio than 7075-T6 aluminium. These results were successfully applied to a multifunctional, lightweight, 3U CubeSat chassis design, fabricated from Inconel 718; resulting in a structurally mass efficient satellite bus. Additionally, modal analysis was conducted on the CubeSat chassis loaded with representative payload masses to evaluate the dynamic modal response of the final structure. Vibration testing was conducted in accordance with NASA General Environmental Verification Standard qualification standards, demonstrating the survivability of the chassis under launch conditions. It was shown this metamaterial based design approach could provide a lighter, stiffer chassis than manufactured from traditional aluminum alloy components
The employees point of view in the performance measurement system in tuscany health authorities
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Buying happiness in an unequal world: Rank of income more strongly predicts well-being in more unequal countries
Does income rank matter more for well-being in more unequal countries? Using more than 160,000 observations from 24 countries worldwide, we replicate previous studies and show that the ranked position of an individual’s income strongly predicts life evaluation and positive daily emotional experiences, while absolute and reference income generally have weak orno effects. Furthermore, we find the association between income rank and an individual’s well-being to be significantly larger in countries where income inequality, represented by the share of taxable income held by the top 1 %of income earners,is high. These results are robust to using an alternative measure of income inequality and different reference group specifications.Our findingssuggest that people in more unequal societies place greater weight on the pursuit of higher income ranks, which may contribute to enduringincome inequality in places where greater well-beingcan be bought from moving up the income ladder
Thyroid nodules treated with percutaneous radiofrequency thermal ablation: a comparative study
Percutaneous radiofrequency thermal ablation (RTA) was reported as an effective tool for the management of thyroid nodules (TNs). The aim of this study was to investigate the effects of RTA and to establish whether they were treatment-related by comparison with a matched, untreated control group
Assessment of gold bio-functionalization for wide-interface biosensing platforms
The continuous improvement of the technical potential of bioelectronic devices for biosensing applications will provide clinicians with a reliable tool for biomarker quantification down to the single molecule. Eventually, physicians will be able to identify the very moment at which the illness state begins, with a terrific impact on the quality of life along with a reduction of health care expenses. However, in clinical practice, to gather enough information to formulate a diagnosis, multiple biomarkers are normally quantified from the same biological sample simultaneously. Therefore, it is critically important to translate lab-based bioelectronic devices based on electrolyte gated thin-film transistor technology into a cost-effective portable multiplexing array prototype. In this perspective, the assessment of cost-effective manufacturability represents a crucial step, with specific regard to the optimization of the bio-functionalization protocol of the transistor gate module. Hence, we have assessed, using surface plasmon resonance technique, a sustainable and reliable cost-effective process to successfully bio-functionalize a gold surface, suitable as gate electrode for wide-field bioelectronic sensors. The bio-functionalization process herein investigated allows to reduce the biorecognition element concentration to one-tenth, drastically impacting the manufacturing costs while retaining high analytical performance
Cyclosporin A blocks calcium-dependent pathways of gene activation
We have used an interleukin-2 (IL-2) promoter-CAT fusion gene to study activation of IL-2 gene expression by IL-1, phytohemagglutinin (PHA), phorbol myristate acetate (PMA), and calcium ionophore in the murine thymoma line EL4 and the human lymphoma line Jurkat. The two cell lines respond differently to combinations of these stimuli. IL-1 in combination with suboptimal concentration of PMA induced chloramphenicol acetyltransferase (CAT) activity in EL4. In Jurkat cells, IL-1 failed to synergize with PMA or PHA. Cotransfection with the IL-2/CAT gene and a construct capable of expressing murine T-cell type IL-1 receptors converted Jurkat cells to IL-1 responsiveness. IL-1 in combination with PHA but not with PMA resulted in induction of CAT activity in these cells. Induction of IL-2/CAT activity by all stimuli in both cell lines was blocked by the presence of EGTA in the culture medium. EGTA did not inhibit IL-1/PMA activation of an SV40 early promoter-CAT fusion gene in either EL4 or Jurkat cells; therefore, calcium was not required for IL-1 or PMA signal transduction. Jurkat cells were shown to differ from EL4 in their requirement for calcium mobilization. Two different calcium-dependent pathways of gene activation were distinguished, both of which were blocked by the immunosuppressive drug cyclosporin A
Pulmonary arterial hypertension: from the kingdom of the near-dead to multiple clinical trial meta-analyses
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Copper Phosphoramidite Catalyzed Enantioselective Ring-Opening of Oxabicyclic Alkenes: Remarkable Reversal of Stereocontrol
Once daily levocetirizine for the treatment of allergic rhinitis and chronic idiopathic urticaria
Levocetirizine is the pharmacologically active enantiomer of cetirizine. It is a potent histamine H-1 receptor antagonist with anti-inflammatory and antiallergic properties. The review analyses the levocetirizine’s properties in terms of safety and efficacy both in allergic rhinitis and urticarioid syndromes
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