Search results for "Spar"

Experiments with an adaptive Bayesian restoration method

1989

Abstract This paper describes a Bayesian restoration method applied to two-dimensional measured images, whose detector response function is not completely known. The response function is assumed Gaussian with standard deviation depending on the estimate of the local density of the image. The convex hull of the K -nearest neighbours ( K NN) of each ‘on’ pixel is used to compute the local density. The method has been tested on ‘sparse’ images, with and without noise background.

Effect of current on the sintering of pre-oxidized copper powders by SPS

2017

Abstract As mentioned in the literature, SPS (Spark Plasma Sintering) technology combines uniaxial charge and pulsed currents to achieve the rapid sintering of powders. Although the utilization of current is often reported, an understanding of its role in the sintering mechanisms is still a subject of controversy. In fact, the oxide layer around metal particles is sometimes considered to be a dielectric gap in which discharges may occur: these discharges can clean the surface of particles and enhance densification. In this paper, an oxide layer was grown on the particle surface of a copper powder, and the growth enabled the study of the role of current on such dielectric layers. The powders…

Steroidal glycosides from the Vietnamese cultivar Cordyline fruticosa “Fairchild red”

2021

Abstract A phytochemical study of Cordyline fruticosa “Fairchild red” (Asparagaceae) from Vietnam, led to the isolation of fourteen steroidal glycosides, including twelve previously undescribed along with two known ones. Ten compounds were obtained by successive solid/liquid chromatographic methods from an aqueous-ethanolic extract of the roots, and four from the aerial parts. Their structures were elucidated mainly by spectroscopic analysis 2D NMR and mass spectroscopy (ESI-MS), as spirostanol glycosides, 5α-spirost-25(27)-ene-1β,3β,4α-triol 1-O-β-D-fucopyranoside, 5α-spirost-(25)27-ene-1β,3β,4α-triol 1-O-β-D-xylopyranoside, 5α-spirost-(25)27-ene-1β,3β,4α-triol 1-O-α-L-rhamnopyranosyl-(1 →…

Why is COVID-19 especially impacting the African American population?

2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for the ongoing coronavirus disease 2019 (COVID-19) pandemic, penetrates human cells through direct binding with ...

The Role of Institutions in the Migration of Corporate Governance Practice into Emerging Economies The Case of Africa

2016

This study examines the role of institutional environment in influencing the migration of corporate governance best practice into 22 emerging African economies. Using a unique and comprehensive sample hand-collected sample of 202 IPO firms from across the continent we adopt a novel institutional logics perspective in studying the diffusion of CEO salary disclosure – a central element of corporate transparency. Our findings reveal that the adoption of CEO salary disclosure by firms is more likely in more homogenous informal institutional contexts. Complementarities arising from disclosure originating from an Anglo-American shareholder value governance framework and indigenous formal institut…

El principio de buena administración y la gobernanza en la contratación pública

2020

Las exigencias de la sociedad sobre la administración pública pasan por profundizar en el comportamiento y en la dedicación profesional, sobre todo, de los administradores y gestores públicos. Todo ello no es más que trasunto del principio de buena administración que, como ya he destacado, es hoy un derecho de los ciudadanos, que reclama mayor objetividad en la toma de decisiones, mayor intensidad en la defensa de los derechos de los ciudadanos, más transparencia, más control y, sobre todo una más proactiva rendición de cuentas. Se trata, en definitiva, de imbuir a los gestores públicos y a los ciudadanos que más frecuente y estrechamente se relacionan con ellos, de sentimientos de ética, d…

Importance of social and sustainability reporting in ensuring transparency and disclosure

2014

Tra ambiguità e malinteso: schermaglie di una «battaglia per l’identità» in una conversazione tra mafiosi

2015

Gli scambi comunicativi tra membri di Cosa Nostra sono regolati dalla duplice restrizione della legge del silenzio verso il mondo esterno e dall'obbligo di dire la verità all'interno del sodalizio. A tal fine, il linguaggio mafioso ricorre all’obliquità semantica che fornisce ai parlanti un ampio margine di libertà consentendo loro di non esplicitare le proprie reali intenzioni. È questa la ragione per la quale Tommaso Buscetta ha definito Cosa Nostra come "il regno dei discorsi incompleti". L'ordine del discorso mafioso si basa spesso sulla pratica di quello che Jankélévitch ha definito il "malinteso doppiamente beninteso” uno scambio che si fonda non tanto su una falsa relazione quanto su…

Structural modelling and mechanical tests supporting the design of the ATHENA X-IFU thermal filters and WFI optical blocking filter

2018

Copyright 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. ATHENA is a Large high energy astrophysics space mission selected by ESA in the Cosmic Vision 2015-2025 Science Program. It will be equipped with two interchangeable focal plane detectors: the X-Ray Integral Field Unit (X-IFU) and the Wide Field Imager (WFI). Both detectors require x-ray transparent filters to fully exploit their sensitivity. In order to maximize the X-ray tra…

Reproducible research practices, openness and transparency in health economic evaluations: study protocol for a cross-sectional comparative analysis

2020

INTRODUCTION: There has been a growing awareness of the need for rigorously and transparent reported health research, to ensure the reproducibility of studies by future researchers. Health economic evaluations, the comparative analysis of alternative interventions in terms of their costs and consequences, have been promoted as an important tool to inform decision-making. The objective of this study will be to investigate the extent to which articles of economic evaluations of healthcare interventions indexed in MEDLINE incorporate research practices that promote transparency, openness and reproducibility. METHODS AND ANALYSIS: This is the study protocol for a cross-sectional comparative ana…