939 research outputs found
Dissolution experiments of commercial PWR (52 MWd/kgU) and BWR (53 MWd/kgU) spent nuclear fuel cladded segments in bicarbonate water under oxidizing conditions. Experimental determination of matrix and instant release fraction
The denominated instant release fraction (IRF) is considered in performance assessment (PA) exercises to govern the dose that could arise from the repository. A conservative definition of IRF comprises the total inventory of radionuclides located in the gap, fractures, and the grain boundaries and, if present, in the high burn-up structure (HBS). The values calculated from this theoretical approach correspond to an upper limit that likely does not correspond to what it will be expected to be instantaneously released in the real system. Trying to ascertain this IRF from an experimental point of view, static leaching experiments have been carried out with two commercial UO2 spent nuclear fuels (SNF): one from a pressurized water reactor (PWR), labelled PWR, with an average burn-up (BU) of 52 MWd/kgU and fission gas release (FGR) of 23.1%, and one from a boiling water reactor (BWR), labelled BWR, with an average BU of and 53 MWd/kgU and FGR of 3.9%.; One sample of each SNF, consisting of fuel and cladding, has been leached in bicarbonate water during one year under oxidizing conditions at room temperature (25 +/- 5) degrees C. The behaviour of the concentration measured in solution can be divided in two according to the release rate. All radionuclides presented an initial release rate that after some days levels down to a slower second one, which remains constant until the end of the experiment. Cumulative fraction of inventory in aqueous phase (FIAPc) values has been calculated. Results show faster release in the case of the PWR SNF. In both cases Np, Pu, Am, Cm, Y, Tc, La and Nd dissolve congruently with U, while dissolution of Zr, Ru and Rh is slower. Rb, Sr, Cs and Mo, dissolve faster than U. The IRF of Cs at 10 and 200 days has been calculated, being (3.10 +/- 0.62) and (3.66 +/- 0.73) for PWR fuel, and (035 +/- 0.07) and (0.51 +/- 0.10) for BWR fuel. (C) 2015 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (author's final draft
Physio social reform through restorative architecture: towards the design of a pre-release centre for female offenders in Durban.
Masters Degree. University of KwaZulu-Natal, Durban.This dissertation has been conducted to investigate the need for prison environments to redefine
reform through the introduction of post punishment prisons which cater beyond punishment
and responds to user specific needs. This research will explore the interrelationship between
architecture and its users, through behaviourism, restorative processes, and gender sensitive
design approaches which could redefine the reform of female offenders as a holistic process.
Past and current prison environments have been explored in this dissertation in order to
motivate for a new post-punishment model which would focus on promoting reflection and
initiate offender reintegration, in the hopes of closing the gap between incarceration and
reform, and ultimately reducing the high rates of recidivism in South Africa.
Using an exploratory study that fully relies on a qualitative constructivist methodology, allows
the researcher to gather insightful information regarding the female offenders’ needs, their
experiences within the prison environment as well as their current process for reform. This,
along with the analysis of the existing literature, and various precedent studies, case studies
and a series of in- depth interviews with staff officials from the Westville Female corrections
centre and offender advocates from grass-roots NGO’s, established various themes which
responded to the research concepts of gender sensitive architecture, restorative environments
and post punishment reform.
Furthermore, as a result of the findings from the fieldwork component, this research concludes
that despite the Department of Correctional Services attempts to promote offender reform
within current prison environments, the outdated prison models, along with the lack of
understanding regarding the post punishment phases of reflection and reintegration, has
resulted in the current prison environment not being conducive towards the holistic reform of
offenders.
This dissertation concludes that for prison environments to facilitate the holistic reform of
offender must incorporate the tripartite solution of:
1. Gender sensitive architecture – responds to female offender needs.
2. Restorative environments: facilitates the processes of reflection and reintegration.
3. Post punishment reform – redefines reform so it is physio socially holistic
Staff Perspectives Regarding the Influence of Trauma on the Intimate Partnering Experiences of Adolescent Mothers in Residential Foster Care
Adolescent girls in foster care are disproportionately vulnerable to pregnancy and parenthood. These experiences of motherhood might be partially attributable to experiences of trauma, including sexual trauma. Trauma, particularly related to domestic violence and sexual abuse, have been linked to subsequent struggles in intimate relationships, such as dating violence or engagement in unsafe sexual behaviors. Although some research has begun to investigate experiences of trauma on relationships, there has been a lack of focus on intimate relationships in general and how they have been influenced by past and/or current traumatic experiences. The present study draws on 12 interviews with program staff who work with adolescent mothers at a residential foster care facility. Staff provided perceptions concerning the mothers’ dating and sexual health experiences to provide recommendations for working with this population. Findings present two overarching themes which attend to the nature of the mothers’ lived relationship experiences (e.g., boundaries, expectations) and how those relationships had been influenced by their past experiences of trauma. Findings provide implications for empirically informed and strengths-based, as opposed to deficit-focused, practice. Future research should focus on further developing trauma-informed care for adolescent mothers in foster care
Relational Representation of Uncertain and Imprecise Time Assess-ments: An Application to Artworks Dating.
Imprecision and uncertainty appear together in many situations of real life and thereforesoft computing techniques must be studied to tackle this problem. Imprecise and uncertainvalues are usually expressed by means of linguistic terms, specially when they have beenprovidedbya human being. This is also the case of temporal information where, inaddition to handling time constraints, we may also have both uncertainty and imprecisionin the description, like in the sentence”It is very possible that Giotto’s Crucifix was paintedby 1289”. To manage both uncertainty (very possible) and imprecision (by 1289) in aseparate way would lead to a quite complicated computation and a lack of comprehensionby the users of the system. Because of these reasons, it is very desirable that bothsources of imperfection of time values are combined into a single value which appropriatelydescribes the intended information. In this work, we extend our previous research on thistopic and we study how to adapt it to relational systems in order to be useful. The finalgoal is obtaining normalized fuzzy values that provide an equivalent information about thedescribed temporal fact than the original ones, for making it possible to store and managethem in a fuzzy relational database. On the other hand, there will be some situationswhere more than one expert opinion about a time period must be taken into account andwe need to find a representative value of them all in order to be stored and managed. Forthe sake of simplicity, comprehensibility and the efficiency in computation (when usingtrapezoidal representation), the fuzzy average is used to find such a representative value
Geometrical control of the magnetization direction in high aspect-ratio PdNi ferromagnetic nano-electrodes
We present a study of electron-beam evaporated Pd0.4Ni0.6 alloy thin films by
means of ferromagnetic resonance measurements on extended films of varying
thickness and anisotropic magnetoresistance measurements of lithographically
patterned high aspect-ratio ferromagnetic electrodes, respectively. The results
reveal that the direction of the magnetization strongly depends on the
electrode lateral dimensions, transitioning from in-plane magnetization for
extended films to out-of-the-plane magnetization for electrode widths below 2-3
microns, reaching 58 degrees off-plane for 100 nm-wide nanoelectrodes.Comment: Preprint submitted to PRB (14 pages, 4 figures
A Quantitative Assessment of the Compatibility of Ultra Wideband with Broadband Wireless Access and Radar Services
In July 2008, following a request made by the Radio Spectrum Policy Unit in DG INFSO (Unit B4), a pilot phase of twelve months was agreed with Member States representatives in the Radio Spectrum Committee. During this time the Institute for the Protection and Security of the Citizen of the EC Joint Research Centre (IPSC-JRC) has been mandated to provide testing facilities to support the development of Community spectrum legal measures under the Radio Spectrum Decision (676/2002/EC). In the frame of this pilot phase, IPSC-JRC has successfully completed the implementation and extensive testing of both a state-of-the-art laboratory test-bed and a simulation tool, which have been specifically designed for two different coexistence studies. Firstly, the coexistence between broadband wireless access (BWA) and ultra wideband (UWB) services in the 3.5 GHz frequency band; and secondly, the coexistence between radiolocation (i.e. radar) and UWB services in the 3.1-3.4 GHz frequency band. The selection of these two coexistence scenarios is not casual and has been made based on the fact that they have been considered highly relevant in the CEPT-ECC studies on UWB mandated by the European Commission.JRC.G.6-Security technology assessmen
Scaling-up climate services with users in Latin America
Latin America farmers are highly vulnerable to climate variability, with crop losses observed throughout the region on a virtually annual basis. For instance, as indicated by the United Nations’ Food and Agriculture Organization (FAO) and World Food Program (WFP), the 2014–2017 drought conditions in Central America affected over 3.5 million people in Guatemala, Honduras and El Salvador. At the same time, local stakeholders and farmers generally have limited access to existing climate and forecast information, do not have sufficient capacities to understand the climate information and/or mechanisms to relate this information to the impact that climate variations can generate at a local level. This precludes the translation of information into actionable knowledge, and therefore into action.
In this study, we describe a process through which scientists and strategic partners have co-developed, tested and scaled out an approach to assess, co-produce, translate and transfer climate information to enable agricultural decision making –the Local Technical Agroclimatic Committees (LTAC). LTACs allow open and clear dialogues about climate variations at multiple timescales, how these can affect crops, and the design of measures to reduce crop loss, particularly providing agronomic recommendations to farmers. We systematically describe the process of evidence generation, creation, partner engagement, scaling up, and monitoring of the approach throughout Latin America.
Currently, 35 LTACs exist in 9 Latin American countries, engaging more than 250 public and private institutions, increasing the resilience and food security of an estimated 330,000 farmers, and potentially transforming how Latin American farmers manage climate risk. The study illustrates changes in institutional and farmers' capacities to co-produce, translate and use climate information and explores how better climate and crop prediction models can effectively underpin this process. We show how strategic alliances with farmer organizations, national public, and private and regional climate outlook forums help deliver improved and accurate climate information to users. Finally, we document how LTACs and their integration with other local-scale processes have led to changes in farmers’ management practices to take better advantage of good climatic conditions or avoid losses
The spanish equality law and the gender balance in the evaluation committees: an opportunity for women’s promotion in higher education
Despite advances in gender policy and equality laws in the twenty-first century, women are still a minority in the full professor category in Europe. Some measures establish gender quotas to balance gatekeeper positions, which will supposedly pave the way to make women’s integration into senior higher education positions easier. In Spain, Organic Act 3/20071 of 22 March on effective equality between women and men launched progressive norms governing gender issues, and the Spanish Science and Technology Act (2011) incorporated measures to promote effective equality in academic institutions. This paper evaluates how Spanish evaluation agencies’ compliance with implementing gender balance has affected the composition of evaluation committees and its impact on the advancement of women in science. Findings reveal some positive figures on women’s representation in recent decades, even though gender-balanced committees do not show any clear evidence of causing this effect. There seems to be no correlation between gender-balanced committees and women’s success rates, suggesting intermediate variables affect women’s low participation in competitive submissions. It explores several factors concerning two agencies’ evaluation procedures, such as formality and transparency, direct/multiple gatekeeping processes, the influence of epistemic cultures, cohorts and confidence of female candidates.Postprint (author's final draft
KinMutRF: a random forest classifier of sequence variants in the human protein kinase superfamily
Background: The association between aberrant signal processing by protein kinases and human diseases such as cancer was established long time ago. However, understanding the link between sequence variants in the protein kinase superfamily and the mechanistic complex traits at the molecular level remains challenging: cells tolerate most genomic alterations and only a minor fraction disrupt molecular function sufficiently and drive disease. Results: KinMutRF is a novel random-forest method to automatically identify pathogenic variants in human kinases. Twenty six decision trees implemented as a random forest ponder a battery of features that characterize the variants: a) at the gene level, including membership to a Kinbase group and Gene Ontology terms; b) at the PFAM domain level; and c) at the residue level, the types of amino acids involved, changes in biochemical properties, functional annotations from UniProt, Phospho.ELM and FireDB. KinMutRF identifies disease-associated variants satisfactorily (Acc: 0.88, Prec:0.82, Rec:0.75, F-score:0.78, MCC:0.68) when trained and cross-validated with the 3689 human kinase variants from UniProt that have been annotated as neutral or pathogenic. All unclassified variants were excluded from the training set. Furthermore, KinMutRF is discussed with respect to two independent kinase-specific sets of mutations no included in the training and testing, Kin-Driver (643 variants) and Pon-BTK (1495 variants). Moreover, we provide predictions for the 848 protein kinase variants in UniProt that remained unclassified. A public implementation of KinMutRF, including documentation and examples, is available online (http://kinmut2.bioinfo.cnio.es). The source code for local installation is released under a GPL version 3 license, and can be downloaded from https://github.com/Rbbt-Workflows/KinMut2. Conclusions: KinMutRF is capable of classifying kinase variation with good performance. Predictions by KinMutRF compare favorably in a benchmark with other state-of-the-art methods (i.e. SIFT, Polyphen-2, MutationAssesor, MutationTaster, LRT, CADD, FATHMM, and VEST). Kinase-specific features rank as the most elucidatory in terms of information gain and are likely the improvement in prediction performance. This advocates for the development of family-specific classifiers able to exploit the discriminatory power of features unique to individual protein families
The Wide-Field X and Gamma-Ray Telescope ECLAIRs aboard the Gamma-Ray Burst Multi-Wavelength Space Mission SVOM
The X and Gamma-ray telescope ECLAIRs is foreseen to be launched on a low
Earth orbit (h=630 km, i=30 degrees) aboard the SVOM satellite (Space-based
multi-band astronomical Variable Objects Monitor), a French-Chinese mission
with Italian contribution. Observations are expected to start in 2013. It has
been designed to detect and localize Gamma-Ray Bursts (GRBs) or persistent
sources of the sky, thanks to its wide field of view (about 2 sr) and its
remarkable sensitivity in the 4-250 keV energy range, with enhanced imaging
sensitivity in the 4-70 keV energy band. These characteristics are well suited
to detect highly redshifted GRBs, and consequently to provide fast and accurate
triggers to other onboard or ground-based instruments able to follow-up the
detected events in a very short time from the optical wavelength bands up to
the few MeV Gamma-Ray domain.Comment: Proccedings of the "2008 Nanjing GRB Conference", June 23-27 2008,
Nanjing, Chin
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