2,126 research outputs found

    Sociotechnical transformation of the livestock market in Tanzania: appropriation of mobile phones by the Maasai and Wasukuma pastoralists

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    This thesis presents findings from a qualitative enquiry into the rapid uptake of the mobile phone by pastoral communities in Tanzania and its use as a tool to tackle marketing constraints. The research design involves an interregional comparative analysis of two key production regions: Arusha and the Lake Zone, and two groups of livestock producers (the Maasai pastoralists and Wasukuma agro-pastoralists respectively). Applying the Social Shaping of Technology (SST) perspective from Science and Technology Studies (STS), and in particular the concept of ‘appropriation’, the study examines the embrace of mobile phones by those producers – who keep livestock under the extensive (pastoralist) and semi-intensive (agro-pastoralist) systems respectively. The thesis examines the extent to which the mobile phone is changing how livestock keepers interact in the livestock market and how this is affecting their livelihoods. The thesis shows that the significance of the mobile phone varies with user groups; for instance, for the Maasai who still lead a nomadic life, the mobile phone is used ‘conservatively’ to communicate about herd management and to coordinate household affairs in ways that do not substantially disrupt traditional social practices and roles. In contrast, the Wasukuma agro-pastoralists use mobile phones to introduce new processes to support production and marketing, one good example being the strategy used to coordinate transportation of cattle to market. The study findings suggest the extension of the “appropriation” (Williams, Stewart, & Slack, 2005) conceptualisation by adding the possibility of a spectrum from shallow to extended according to users’ role and the context of use. Nevertheless, and in more generic terms, it is possible to say that the mobile phone use did not disrupt some of the traditional practices and trade customs amongst the Maasai, and it has reinforced the innovative behaviour of the Wasukuma. The thesis also examines a parallel initiative whereby aid agencies and public bodies in Tanzania supported the development of the Livestock Information Network and Knowledge System (LINKS), as an ICT platform designed to improve the livestock market by sharing market information. However, studies show that LINKS has not had the intended effect, is not trusted and has not been adopted by many pastoralists. The study shows how the concept of trust, which is key in market dynamics and trade relations, has been reshaped, because the mobile phone has supported informal communications that reinforce traditional methods of policing trust in the market. The thesis contributes to ongoing debates surrounding the conceptualisation of Information and Communication Technologies for Development (ICT4D). The failure of early ICT4D initiatives was attributed to a failure to address users’ specific requirements, due to gaps in the translation process, as well as to socio-political and technical fragilities such as the lack of adequate infrastructure, and a deficient social learning process. The initial reworking of ICT4D highlighted the need to design technology as a specific solution appropriate to particular contexts/user groups. These were seen as finished solutions (corresponding to the idea of a ‘technical fix’). Focusing upon ‘appropriation’, in line with the Social Shaping of Technology – Mark 2 approach – allows scope for a further rethinking of ICT4D which addresses not just design but the active role of users in shaping technological innovation to the context and purposes of communities in developing countries

    Fingerprinting the Type-Z three Higgs doublet models

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    There has been great interest in a model with three Higgs doublets in which fermions with a particular charge couple to a single and distinct Higgs field. We study the phenomenological differences between the two common incarnations of this so-called Type-Z 3HDM. We point out that the differences between the two models arise from the scalar potential only. Thus we focus on observables that involve the scalar self-couplings. We find it difficult to uncover features that can uniquely set apart the Z3Z_3 variant of the model. However, by studying the dependence of the trilinear Higgs couplings on the nonstandard masses, we have been able to isolate some of the exclusive indicators for the Z2×Z2Z_2\times Z_2 version of the Type-Z 3HDM. This highlights the importance of precision measurements of the trilinear Higgs couplings.Comment: 15 pages, 4 captioned figure

    SLaMA-URM method for the seismic vulnerability assessment of UnReinforced Masonry structures: Formulation and validation for a substructure

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    An analytical procedure based on the SLaMA (Simplified Lateral Mechanism Analysis) method is proposed for the seismic vulnerability assessment of UnReinforced Masonry (URM) structures. The procedure considers an equivalent frame discretization for the structure (pier, spandrel, and joint elements) and includes: (i) the evaluation of moment‒rotation capacity curves at each pier-spandrel subassembly; (ii) the assessment of the hierarchy of strength in each subassembly; and (iii) the calculation of the structure capacity curve according to the expected failure mechanism. Validation of the proposed SLaMA-URM procedure is achieved in a one-story URM substructure tested under lateral cyclic loading. The analytical predictions are compared with numerical ones from a 2D continuous finite element (FE) model based on a macro-modelling strategy. The flexural capacity of the components is estimated using a monolithic beam analogy, and the results compared with those from traditional sectional analysis. The influence of the substructure geometry on the hierarchy of strength at the subassembly and global levels is investigated. An analytical formulation of the pier-spandrel joint strength is also proposed to be considered in the assessment of the hierarchy of strength. The method is validated for a one-story substructure subjected to lateral in-plane loading. Results, in terms of crack patterns and capacity curves, are in relatively good agreement with the experimental and FE results, even when a bilinear curve approximation is used. The potential of the SLaMA-URM method for the seismic assessment of URM buildings is demonstrated, whose application to a larger URM structure is planned as a subsequent study

    ViolĂȘncia no futebol brasileiro a influencia dos problemas socioculturais e econĂŽmicos da sociedade brasileira na violĂȘncia do futebol local

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    Crescente no futebol brasileiro, a violĂȘncia Ă© um fator preocupante para os que apreciam o esporte mais popular do mundo. NĂŁo presente apenas no jogo em si, a violĂȘncia tem crescido nesse esporte principalmente fora de campo, entre os torcedores. Os nĂșmeros de pessoas feridas e atĂ© mortas durante, antes ou depois a um jogo de futebol, Ă© preocupante. A cada partida entre duas equipes rivais mais torcedores sĂŁo atingidos por essa onda de violĂȘncia que tomou conta do futebol. Muitas pessoas afirmam que essa atitude Ă© causada pelo jogo em si, ou seja, o futebol estimula a violĂȘncia dos torcedores, que refletem as caracterĂ­sticas deste esporte. Uma outra linha afirma que os crescentes casos de violĂȘncia nesta modalidade esportiva sĂŁo frutos dos problemas socioculturais e econĂŽmicos enfrentados pela população brasileira. A violĂȘncia seria um reflexo do que ocorre na sociedade, sendo manifestada no futebol. Nesta monografia procuro analisar ambas vertentes, tentando mostrar como que o futebol nĂŁo Ă© violento por natureza, nĂŁo induz o torcedor a atos de truculĂȘncia. Mostro que os casos de brigas e mortes sĂŁo reflexos do cotidiano e que afloram neste esporte devido Ă  paixĂŁo popular por esta modalidade esportiva

    Follow-up of the air pollution and the human male-to-female ratio analysis in SĂŁo Paulo, Brazil: a times series study

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    Objectives in order to assess if ambient air pollution in urban areas could be related to alterations in male/female ratio this study objectives to evaluate changes in ambient particulate matter (PM10) concentrations after implementation of pollution control programmes in SĂŁo Paulo city and the secondary sex ratio (SRR).Design and methods A time series study was conducted. SĂŁo Paulo's districts were stratified according to the PM10 concentrations levels and were used as a marker of overall air pollution. the male ratio was chosen to represent the secondary sex ratio (SSR=total male birth/total births). the SSR data from each area was analysed according to the time variation and PM10 concentration areas using descriptive statistics. the strength association between annual average of PM10 concentration and SSR was performed through exponential regression, and it was adopted as a statistical significance level of p<0.05.Results the exponential regression showed a negative and significant association between PM10 and SSR. SSR varied from 51.4% to 50.7% in SĂŁo Paulo in the analysed period (2000-2007). Considering the PM10 average concentration in SĂŁo Paulo city of 44.72g/m(3) in the study period, the SSR decline reached almost 4.37%, equivalent to 30934 less male births.Conclusions Ambient levels of PM10 are negatively associated with changes in the SSR. Therefore, we can speculate that higher levels of particulate pollution could be related to increased rates of female births.Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq)Universidade Federal de SĂŁo Paulo UNIFESP, ICAQF, Dept Ciencias Exatas & Terra, SĂŁo Paulo, BrazilUniv SĂŁo Paulo, Sch Med, Dept Pathol, Lab Expt Air Pollut LIM05, SĂŁo Paulo, BrazilUniversidade Federal de SĂŁo Paulo UNIFESP, ICAQF, Dept Ciencias Exatas & Terra, SĂŁo Paulo, BrazilCNPq: 573813/2008-5: FAPESP - 2008/57717-6Web of Scienc

    Spatiotemporal distribution of the seismicity along the Mid-Atlantic Ridge north of the Azores from hydroacoustic data: Insights into seismogenic processes in a ridge-hot spot context

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    The seismicity of the North Atlantic was monitored from May 2002 to September 2003 by the 'SIRENA array' of autonomous hydrophones. The hydroacoustic signals provide a unique data set documenting numerous low-magnitude earthquakes along the section of the Mid-Atlantic Ridge (MAR) located in a ridge-hot spot interaction context. During the experiment, 1696 events were detected along the MAR axis between 40 degrees N and 51 degrees N, with a magnitude of completeness level of m(b) approximate to 2.4. Inside the array, location errors are in the order of 2 km, and errors in the origin time are less than 1 s. From this catalog, 15 clusters were detected. The distribution of source level (SL) versus time within each cluster is used to discriminate clusters occurring in a tectonic context from those attributed to non-tectonic (i.e. volcanic or hydrothermal) processes. The location of tectonic and non-tectonic sequences correlates well with regions with positive and negative Mantle Bouguer Anomalies (MBAs), indicating the presence of thinner/colder and thicker/warmer crust respectively. At the scale of the entire array, both the complete and declustered catalogs derived from the hydroacoustic signals show an increase of the seismicity rate from the Azores up to 43 degrees 30'N suggesting a diminishing influence of the Azores hot spot on the ridge-axis temperature, and well correlated with a similar increase in the along-axis MBAs. The comparison of the MAR seismicity with the Residual MBA (RMBA) at different scales leads us to think that the low-magnitude seismicity rates are directly related to along-axis variations in lithosphere rheology and temperatures.info:eu-repo/semantics/publishedVersio

    Topoisomerase 1 Inhibition in MYC-Driven Cancer Promotes Aberrant R-Loop Accumulation to Induce Synthetic Lethality

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    CRISPR screening reveals topoisomerase 1 as an immediately actionable vulnerability in cancers harboring MYC as a driver oncoprotein that can be targeted with clinically approved inhibitors. MYC is a central regulator of gene transcription and is frequently dysregulated in human cancers. As targeting MYC directly is challenging, an alternative strategy is to identify specific proteins or processes required for MYC to function as a potent cancer driver that can be targeted to result in synthetic lethality. To identify potential targets in MYC-driven cancers, we performed a genome-wide CRISPR knockout screen using an isogenic pair of breast cancer cell lines in which MYC dysregulation is the switch from benign to transformed tumor growth. Proteins that regulate R-loops were identified as a potential class of synthetic lethal targets. Dysregulated MYC elevated global transcription and coincident R-loop accumulation. Topoisomerase 1 (TOP1), a regulator of R-loops by DNA topology, was validated to be a vulnerability in cells with high MYC activity. Genetic knockdown of TOP1 in MYC-transformed cells resulted in reduced colony formation compared with control cells, demonstrating synthetic lethality. Overexpression of RNaseH1, a riboendonuclease that specifically degrades R-loops, rescued the reduction in clonogenicity induced by TOP1 deficiency, demonstrating that this vulnerability is driven by aberrant R-loop accumulation. Genetic and pharmacologic TOP1 inhibition selectively reduced the fitness of MYC-transformed tumors in vivo. Finally, drug response to TOP1 inhibitors (i.e., topotecan) significantly correlated with MYC levels and activity across panels of breast cancer cell lines and patient-derived organoids. Together, these results highlight TOP1 as a promising target for MYC-driven cancers.Significance: CRISPR screening reveals topoisomerase 1 as an immediately actionable vulnerability in cancers harboring MYC as a driver oncoprotein that can be targeted with clinically approved inhibitors

    Performances of Adaptive MultiBLUP, Bayesian regressions, and weighted-GBLUP approaches for genomic predictions in Belgian Blue beef cattle.

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    BACKGROUND: Genomic selection has been successfully implemented in many livestock and crop species. The genomic best linear unbiased predictor (GBLUP) approach, assigning equal variance to all SNP effects, is one of the reference methods. When large-effect variants contribute to complex traits, it has been shown that genomic prediction methods that assign a higher variance to subsets of SNP effects can achieve higher prediction accuracy. We herein compared the efficiency of several such approaches, including the Adaptive MultiBLUP (AM-BLUP) that uses local genomic relationship matrices (GRM) to automatically identify and weight genomic regions with large effects, to predict genetic merit in Belgian Blue beef cattle. RESULTS: We used a population of approximately 10,000 genotyped cows and their phenotypes for 14 traits, mostly related to muscular development and body dimensions. According to the trait, we found that 4 to 25% of the genetic variance could be associated with 2 to 12 genomic regions harbouring large-effect variants. Noteworthy, three previously identified recessive deleterious variants presented heterozygote advantage and were among the most significant SNPs for several traits. The AM-BLUP resulted in increased reliability of genomic predictions compared to GBLUP (+ 2%), but Bayesian methods proved more efficient (+ 3%). Overall, the reliability gains remained thus limited although higher gains were observed for skin thickness, a trait affected by two genomic regions having particularly large effects. Higher accuracies than those from the original AM-BLUP were achieved when applying the Bayesian Sparse Linear Mixed Model to pre-select groups of SNPs with large effects and subsequently use their estimated variance to build a weighted GRM. Finally, the single-step GBLUP performed best and could be further improved (+ 3% prediction accuracy) by using these weighted GRM. CONCLUSIONS: The AM-BLUP is an attractive method to automatically identify and weight genomic regions with large effects on complex traits. However, the method was less accurate than Bayesian methods. Overall, weighted methods achieved modest accuracy gains compared to GBLUP. Nevertheless, the computational efficiency of the AM-BLUP might be valuable at higher marker density, including with whole-genome sequencing data. Furthermore, weighted GRM are particularly useful to account for large variance loci in the single-step GBLUP

    Prothrombin G20210A gene mutation, factor V Leiden and anticardiolipin antibodies do not influence renal graft survival after transplantation

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    INTRODUCTION: Thromboembolic complications are important risk factors for graft failure and worse renal transplantation outcome. Patients with thrombophilic disorders have a higher risk of thromboembolic complications. The prevalence of thrombophilic disorders and the associated risk for graft failure and for intravascular thrombosis were analyzed in renal transplant recipients. METHODS: This is a cohort study of 388 adult recipients investigated regarding the presence of thrombophilia, through the search for anticardiolipin antibodies (aCL) via ELISA and FV G1691A and PT G20210A gene mutations by multiplex PCR. RESULTS: Thrombophilic disorders were identified in 25.8% of the patients. The 2-year graft survival was similar among patients with and without thrombophilic disorder (94% versus 94%, p = 0.53), and so was the survival free of intravascular thrombosis (97% versus 97%, p = 0.83). The prevalence of intravascular thrombosis was similar in both groups (3% versus 3.5%, p = 0.82). Patients with previous kidney transplantation had a higher risk of graft failure (OR 20.8, p < 0.001) and of intravascular thrombosis (OR 6.8, p = 0.008). CONCLUSIONS: The prevalences of FV G1691A and PT G20210A gene mutations in this cohort of patients were similar to those of the general non-transplanted population. The prevalence of aCL antibodies was higher in this cohort than that observed in healthy individuals. The thrombophilic markers studied did not predict the medium-term survival of renal transplant.INTRODUÇÃO: ComplicaçÔes tromboembĂłlicas sĂŁo importantes fatores de risco para perda do enxerto e pior evolução apĂłs o transplante renal. Pacientes com defeito trombofĂ­lico apresentam maior risco de complicaçÔes tromboembĂłlicas. Foram analisados, entre receptores de transplante renal, a prevalĂȘncia de defeito trombofĂ­lico e o risco atribuĂ­do a esta condição para a perda do enxerto e para o desenvolvimento de tromboses intravasculares. MÉTODOS: Estudo do tipo coorte incluindo 388 receptores adultos analisados quanto Ă  presença de trombofilia de acordo com a pesquisa de anticorpos anticardiolipina (aCL) por ELISA e das mutaçÔes G1691A no gene do fator V (FV) e G20210A no gene da protrombina (PT) por PCR multiplex. RESULTADOS: Defeito trombofĂ­lico foi identificado em 25,8% dos pacientes. As taxas de sobrevida de 2 anos do enxerto foram semelhantes entre os pacientes com e sem defeito trombofĂ­lico (94% versus 94%, p = 0,53), bem como a sobrevida dos enxertos livres de tromboses intravasculares (97% versus 97%, p = 0,83). Pacientes com defeito trombofĂ­lico apresentaram prevalĂȘncia de tromboses intravasculares semelhante Ă  do grupo-controle (3% versus 3,5%, p = 0,82). O transplante renal anterior foi associado a maior risco de perda de enxerto (OR 20,8, p < 0,001) e de ocorrĂȘncia de tromboses intravasculares (OR 6,8, p = 0,008). CONCLUSÕES: As prevalĂȘncias das mutaçÔes FV G1691A e PT G20210A na população estudada foram semelhantes Ă s da população geral nĂŁo transplantada, e a prevalĂȘncia de anticorpos aCL superou a observada entre os indivĂ­duos sadios. NĂŁo houve associação entre os marcadores de trombofilia estudados e a sobrevida em mĂ©dio prazo do transplante renal.UNIFESP Departamento de Medicina, Disciplina de HematologiaUNIFESP Departamento de Medicina, Disciplina de NefrologiaUNIFESP Departameto de Medicina, Disciplina de ReumatologiaUNIFESP Departamento de Medicina Preventiva, Disciplina de BioestatĂ­sticaUniversidad de Antofagasta Departamento de Tecnologia MedicaUNIFESP, Depto. de Medicina, Disciplina de HematologiaUNIFESP, Depto. de Medicina, Disciplina de NefrologiaUNIFESP, Departameto de Medicina, Disciplina de ReumatologiaUNIFESP, Depto. de Medicina Preventiva, Disciplina de BioestatĂ­sticaSciEL
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