118 research outputs found
Corruption in migration management: a network perspective
This paper explores the relation between networks as an emerging mode of public governance and corruption. Adopting the theoretical lens of actor-network theory (ANT), the paper investigates an Italian episode of corruption related to the awarding of government contracts for the management of the Mineo’s CARA, the Europe's largest reception centre for migrants. The analysis shows that a governance network may turn corruption itself into a network where abuse of power can proliferate thanks to the opacity resulting from the multiplicity of actors, interactions, and fragmentation characterizing the governance system
Characterization of materials used in the manufacture of ceramic tile with incorporation of ornamental rock waste
The production of ceramic tiles, such as tiles, has a great environmental impact, either in
the extraction of natural raw materials or gas emissions in the burning stages. The use of industrial
solid waste in ceramic materials can contribute to the reduction of these impacts, according to the
characteristics of solid waste and its interaction with ceramic materials in the processing steps. Thus,
this study aimed to characterize the materials needed to make a ceramic tile with incorporation of
ornamental rock waste (ORW), thus evaluating its main characteristics regarding the feasibility of this
incorporation. The physical characterization of the clays used in the production of ceramic artifacts
was performed, and for the waste the mineralogical analyzes were performed, through x-ray diffraction
(XRD), microstructure analysis from confocal optical microscopy, after sintering the prototypes and
chemical analysis by X-ray spectroscopy (EDX). Soon after the raw materials went through the step
of conformation and preparation of the prismatic specimens by the process of extrusion of the ceramic
mass, with an incorporation of the ORW in 0% and 15% of the ceramic mass, for its subsequent The
prototypes were sintered at three different temperatures (850 °C, 950 °C and 1,050 °C). The specimens
were submitted to technological tests of mechanical resistance, water absorption, firing shrinkage and
porosity to evaluate the incorporation viability. The results indicated the presence of quartz particles
in all raw materials, and also that the clays of the study region are predominantly kaolinitic. The
presence of these materials in the ceramic masses directly influences the micrographs, because they
result in the formation of liquid phase, inert particles that can turn the site into a stress concentration
point and when incorporated in the ORW the specimens met the technical specifications of the
Brazilian standard for application on ceramic tiles. The results found in the technological tests carried
out, that the incorporation of 15% of ornamental rock waste in both clays did not affect the tile
properties, indicating the feasibility of incorporating this waste in civil construction, minimizing the
impacts generated
AWAKE, the advanced proton driven plasma wakefield acceleration experiment at CERN
The Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) aims at studying plasma wakefield generation and electron acceleration driven by proton bunches. It is a proof-of-principle R&D experiment at CERN and the world׳s first proton driven plasma wakefield acceleration experiment. The AWAKE experiment will be installed in the former CNGS facility and uses the 400 GeV/c proton beam bunches from the SPS. The first experiments will focus on the self-modulation instability of the long (rms ~12 cm) proton bunch in the plasma. These experiments are planned for the end of 2016. Later, in 2017/2018, low energy (~15 MeV) electrons will be externally injected into the sample wakefields and be accelerated beyond 1 GeV. The main goals of the experiment will be summarized. A summary of the AWAKE design and construction status will be presented
Inhibition of Enterovirus 71 (EV-71) Infections by a Novel Antiviral Peptide Derived from EV-71 Capsid Protein VP1
Enterovirus 71 (EV-71) is the main causative agent of hand, foot and mouth disease (HFMD). In recent years, EV-71 infections were reported to cause high fatalities and severe neurological complications in Asia. Currently, no effective antiviral or vaccine is available to treat or prevent EV-71 infection. In this study, we have discovered a synthetic peptide which could be developed as a potential antiviral for inhibition of EV-71. Ninety five synthetic peptides (15-mers) overlapping the entire EV-71 capsid protein, VP1, were chemically synthesized and tested for antiviral properties against EV-71 in human Rhabdomyosarcoma (RD) cells. One peptide, SP40, was found to significantly reduce cytopathic effects of all representative EV-71 strains from genotypes A, B and C tested, with IC50 values ranging from 6–9.3 µM in RD cells. The in vitro inhibitory effect of SP40 exhibited a dose dependent concentration corresponding to a decrease in infectious viral particles, total viral RNA and the levels of VP1 protein. The antiviral activity of SP40 peptide was not restricted to a specific cell line as inhibition of EV-71 was observed in RD, HeLa, HT-29 and Vero cells. Besides inhibition of EV-71, it also had antiviral activities against CV-A16 and poliovirus type 1 in cell culture. Mechanism of action studies suggested that the SP40 peptide was not virucidal but was able to block viral attachment to the RD cells. Substitutions of arginine and lysine residues with alanine in the SP40 peptide at positions R3A, R4A, K5A and R13A were found to significantly decrease antiviral activities, implying the importance of positively charged amino acids for the antiviral activities. The data demonstrated the potential and feasibility of SP40 as a broad spectrum antiviral agent against EV-71
Serum Stabilities of Short Tryptophan- and Arginine-Rich Antimicrobial Peptide Analogs
Several short antimicrobial peptides that are rich in tryptophan and arginine residues were designed with a series of simple modifications such as end capping and cyclization. The two sets of hexapeptides are based on the Trp- and Arg-rich primary sequences from the "antimicrobial centre" of bovine lactoferricin as well as an antimicrobial sequence obtained through the screening of a hexapeptide combinatorial library.HPLC, mass spectrometry and antimicrobial assays were carried out to explore the consequences of the modifications on the serum stability and microbicidal activity of the peptides. The results show that C-terminal amidation increases the antimicrobial activity but that it makes little difference to its proteolytic degradation in human serum. On the other hand, N-terminal acetylation decreases the peptide activities but significantly increases their protease resistance. Peptide cyclization of the hexameric peptides was found to be highly effective for both serum stability and antimicrobial activity. However the two cyclization strategies employed have different effects, with disulfide cyclization resulting in more active peptides while backbone cyclization results in more proteolytically stable peptides. However, the benefit of backbone cyclization did not extend to longer 11-mer peptides derived from the same region of lactoferricin. Mass spectrometry data support the serum stability assay results and allowed us to determine preferred proteolysis sites in the peptides. Furthermore, isothermal titration calorimetry experiments showed that the peptides all had weak interactions with albumin, the most abundant protein in human serum.Taken together, the results provide insight into the behavior of the peptides in human serum and will therefore aid in advancing antimicrobial peptide design towards systemic applications
Faculty accountability and faculty workload: A preliminary cost analysis of their relationship as revealed by PhD productivity
General concerns for faculty accountability are examined in the context of faculty workload and costs. Graduating a PhD student is used as the unit for analysis. The unit is compared to instructional productivity. The data came from a 10-year interval at a major graduate university. Six liberal arts departments with a 225-member faculty provide the PhD output and workload information. Work equivalents are determined from institutional and faculty self-reports. Graduating a PhD is found to be equivalent to one-third of a full workload. Implications are given for comparisons between programs within a university and between types of institutions in the larger system of higher education. Concerns also emerge for improved personnel practices with respect to faculty work assignments.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43583/1/11162_2004_Article_BF00991561.pd
Women and power: a theoretical approach using the example of copreneurial businesses
Despite the gradual recognition of strategic issues related to the integration of women into the economy, female entrepreneurship continues to receive little attention. Family business research attributes this situation to a lack of recognition given to the (decisive) role of women in these organizations. However, there is one type of family governance that formally acknowledges the man/woman combination: the copreneurial company. Copreneurs are couples who run a business together. This theoretical article highlights the role of women in the copreneurial context by distinguishing between formal and informal power- the latter being primarily held by women, but which is no less influential. The distribution of power reduces opposition costs between partners and the social costs of non-compliance, and improves the clarity of the entrepreneurial structure. Moreover, it increases satisfaction and a feeling of equality between the partners. These results can be generalized and shed light on the role of women in other entrepreneurial and social contexts. This article is published as part as part of a collection on the role of women in management and business
Évaluation de la qualité des soudures vis-à-vis de la résistance à la fatigue
Dans le cas d'un assemblage soudé, le niveau de contrainte admissible,
vis-à-vis de la fatigue, dépend de la présence d'imperfections
apportées par l'opération de soudage.
L'augmentation de ce niveau de contrainte passe par une amélioration de
la qualité de la soudure, en particulier, en limitant les défauts
présents et en jouant sur la géométrie du cordon de soudure.
Dans ces conditions, des gains supérieurs à 50 % sur la
résistance à la fatigue peuvent être obtenus.
Dans ce contexte, cet article a pour objectif, tout d'abord, de préciser
les types d'imperfections à améliorer, ensuite, d'indiquer les
méthodes d'évaluation de ces imperfections et de proposer des voies
d'amélioration, enfin, de proposer des méthodes analytiques ou
numériques, afin de prendre en compte la qualité de la soudure au
stade de la conception des composants soudés.
L'application de cette démarche de qualité conduit à la fois
à des gains de fabrication, résultant d'une augmentation des niveaux
de contraintes admissibles et à une meilleure maîtrise du
procédé de soudage et donc à un accroissement de la
fiabilité des produits
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