494 research outputs found
The ethics of uncertainty for data subjects
Modern health data practices come with many practical uncertainties. In this paper, I argue that data subjects’ trust in the institutions and organizations that control their data, and their ability to know their own moral obligations in relation to their data, are undermined by significant uncertainties regarding the what, how, and who of mass data collection and analysis. I conclude by considering how proposals for managing situations of high uncertainty might be applied to this problem. These emphasize increasing organizational flexibility, knowledge, and capacity, and reducing hazard
STROBE-X: X-ray Timing & Spectroscopy on Dynamical Timescales from Milliseconds to Years
We describe a probe-class mission concept that provides an unprecedented view of the X-ray sky, performing timing and 0.2-30 keV spectroscopy over timescales from microseconds to years. The Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X) comprises three primary instruments. The first uses an array of lightweight optics (3-m focal length) that concentrate incident photons onto solid state detectors with CCD-level (85-130 eV) energy resolution, 100 ns time resolution, and low background rates to cover the 0.2-12 keV band. This technology is scaled up from NICER [1], with enhanced optics to take advantage of the longer focal length of STROBE-X. The second uses large-area collimated silicon drift detectors, developed for ESA's LOFT [2], to cover the 2-30 keV band. These two instruments each provide an order of magnitude improvement in effective area compared with its predecessor (NICER and RXTE, respectively). Finally, a sensitive sky monitor triggers pointed observations, provides high duty cycle, high time resolution, high spectral resolution monitoring of the X-ray sky with approx. 20 times the sensitivity of the RXTE ASM, and enables multi-wavelength and multi-messenger studies on a continuous, rather than scanning basis. For the first time, the broad coverage provides simultaneous study of thermal components, non-thermal components, iron lines, and reflection features from a single platform for accreting black holes at all scales. The enormous collecting area allows detailed studies of the dense matter equation of state using both thermal emission from rotation-powered pulsars and harder emission from X-ray burst oscillations. The combination of the wide-field monitor and the sensitive pointed instruments enables observations of potential electromagnetic counterparts to LIGO and neutrino events. Additional extragalactic science, such as high quality spectroscopy of clusters of galaxies and unprecedented timing investigations of active galactic nuclei, is also obtaine
Suv4-20h Histone Methyltransferases Promote Neuroectodermal Differentiation by Silencing the Pluripotency-Associated Oct-25 Gene
Post-translational modifications (PTMs) of histones exert fundamental roles in regulating gene expression. During development, groups of PTMs are constrained by unknown mechanisms into combinatorial patterns, which facilitate transitions from uncommitted embryonic cells into differentiated somatic cell lineages. Repressive histone modifications such as H3K9me3 or H3K27me3 have been investigated in detail, but the role of H4K20me3 in development is currently unknown. Here we show that Xenopus laevis Suv4-20h1 and h2 histone methyltransferases (HMTases) are essential for induction and differentiation of the neuroectoderm. Morpholino-mediated knockdown of the two HMTases leads to a selective and specific downregulation of genes controlling neural induction, thereby effectively blocking differentiation of the neuroectoderm. Global transcriptome analysis supports the notion that these effects arise from the transcriptional deregulation of specific genes rather than widespread, pleiotropic effects. Interestingly, morphant embryos fail to repress the Oct4-related Xenopus gene Oct-25. We validate Oct-25 as a direct target of xSu4-20h enzyme mediated gene repression, showing by chromatin immunoprecipitaton that it is decorated with the H4K20me3 mark downstream of the promoter in normal, but not in double-morphant, embryos. Since knockdown of Oct-25 protein significantly rescues the neural differentiation defect in xSuv4-20h double-morphant embryos, we conclude that the epistatic relationship between Suv4-20h enzymes and Oct-25 controls the transit from pluripotent to differentiation-competent neural cells. Consistent with these results in Xenopus, murine Suv4-20h1/h2 double-knockout embryonic stem (DKO ES) cells exhibit increased Oct4 protein levels before and during EB formation, and reveal a compromised and biased capacity for in vitro differentiation, when compared to normal ES cells. Together, these results suggest a regulatory mechanism, conserved between amphibians and mammals, in which H4K20me3-dependent restriction of specific POU-V genes directs cell fate decisions, when embryonic cells exit the pluripotent state
Rethinking justice beyond human rights. Anti-colonialism and intersectionality in the politics of the Palestinian Youth Movement
This article discusses the politics of the Palestinian Youth Movement (PYM) – a contemporary social movement operating across a number of Arab and western countries. Unlike analysis on the Arab Uprisings which focused on the national dimension of youth activism, we explore how the PYM politics fosters and upholds an explicitly transnational anti-colonial and intersectional solidarity framework, which foregrounds a radical critique of conventional notions of self-determination based on state-framed human rights discourses and international law paradigms. The struggle becomes instead framed as an issue of justice, freedom and liberation from interlocking forms and hierarchies of oppression.
KEYWORDS: Palestine, transnational social movements, intersectionality, human rights, anti-colonialis
Runoff sources and land cover change in the Amazon : an end-member mixing analysis from small watersheds
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Biogeochemistry 105 (2011): 7-18, doi:10.1007/s10533-011-9597-8.The flowpaths by which water moves from watersheds to streams has important consequences for the runoff dynamics and biogeochemistry of surface waters in the Amazon Basin. The clearing of Amazon forest to cattle pasture has the potential to change runoff sources to streams by shifting runoff to more surficial flow pathways. We applied end member mixing analysis (EMMA) to ten small watersheds throughout the Amazon in which solute composition of streamwater and groundwater, overland flow, soil solution, throughfall and rainwater were measured, largely as part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia. We found a range in the extent to which streamwater samples fell within the mixing space determined by potential flowpath end members, suggesting that some water sources to streams were not sampled. The contribution of overland flow as a source of stream flow was greater in pasture watersheds than in forest watersheds of comparable size. Increases in overland flow contribution to pasture streams ranged in some cases from 0% in forest to 27 to 28% in pasture and were broadly consistent with results from hydrometric sampling of Amazon forest and pasture watersheds that indicate 17- to 18-fold increase in the overland flow contribution to stream flow in pastures. In forest, overland flow was an important contribution to stream flow (45 to 57%) in ephemeral streams where flows were dominated by stormflow. Overland flow contribution to stream flow decreased in importance with increasing watershed area, from 21 to 57% in forest and 60 to 89% in pasture watersheds 100 ha. Soil solution contributions to stream flow were similar across watershed area and groundwater inputs generally increased in proportion to decreases in overland flow. Application of EMMA across multiple watersheds indicated patterns across gradients of stream size and land cover that were consistent with patterns determined by detailed hydrometric sampling.This work was supported by National Science Foundation (DEB-0315656, DEB-0640661), the NASA LBA Program (NCC5-686, NCC5-69, NCC5-705, NNG066E88A) and by grants from Brazilian agencies FAPESP (03/13172-2) and CNPq (20199/2005-5)
STROBE-X: X-ray Timing & Spectroscopy on Dynamical Timescales from Milliseconds to Years
We describe a probe-class mission concept that provides an unprecedented view of the X-ray sky, performing timing and 0.2-30 keV spectroscopy over timescales from microseconds to years. The Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X) has three key science drivers: (1) measuring the spin distribution of accreting black holes, (2) understanding the equation of state of dense matter, and (3) exploring the properties of the precursors and electromagnetic counterparts of gravitational wave sources. To perform these science investigations, STROBE-X comprises three primary instruments. The first uses an array of lightweight optics (3-m focal length) that concentrate incident photons onto solid state detectors with CCD-level (85-130 eV) energy resolution, 100 ns time resolution, and low background rates to cover the 0.2-12 keV band. This technology is scaled up from NICER, with enhanced optics to take advantage of the longer focal length of STROBE-X. The second uses large-area collimated silicon drift detectors, developed for ESA's LOFT, to cover the 2-30 keV band. These two instruments each provide an order of magnitude improvement in effective area compared with its predecessor (NICER and RXTE, respectively). Finally, a sensitive sky monitor triggers pointed observations, provides high duty cycle, high time resolution, high spectral resolution monitoring of the X-ray sky with ~20 times the sensitivity of the RXTE ASM, and enables multi-wavelength and multi-messenger studies on a continuous, rather than scanning basis. The STROBE-X mission concept is a rapidly repointable observatory in low-Earth orbit, similar to RXTE or Swift, and will be presented to the 2020 Astrophysics Decadal Survey for consideration as a probe-class mission
Excess risk of adverse pregnancy outcomes in women with porphyria: a population-based cohort study
The porphyrias comprise a heterogeneous group of rare, primarily hereditary, metabolic diseases caused by a partial deficiency in one of the eight enzymes involved in the heme biosynthesis. Our aim was to assess whether acute or cutaneous porphyria has been associated with excess risks of adverse pregnancy outcomes. A population-based cohort study was designed by record linkage between the Norwegian Porphyria Register, covering 70% of all known porphyria patients in Norway, and the Medical Birth Registry of Norway, based on all births in Norway during 1967–2006. The risks of the adverse pregnancy outcomes preeclampsia, delivery by caesarean section, low birth weight, premature delivery, small for gestational age (SGA), perinatal death, and congenital malformations were compared between porphyric mothers and the rest of the population. The 200 mothers with porphyria had 398 singletons during the study period, whereas the 1,100,391 mothers without porphyria had 2,275,317 singletons. First-time mothers with active acute porphyria had an excess risk of perinatal death [adjusted odds ratio (OR) 4.9, 95% confidence interval (CI) 1.5–16.0], as did mothers with the hereditable form of porphyria cutanea tarda (PCT) (3.0, 1.2–7.7). Sporadic PCT was associated with an excess risk of SGA [adjusted relative risk (RR) 2.0, 1.2–3.4], and for first-time mothers, low birth weight (adjusted OR 3.4, 1.2–10.0) and premature delivery (3.5, 1.2–10.5) in addition. The findings suggest women with porphyria should be monitored closely during pregnancy
Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry
Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry
DOI:
10.1080/00207543.2014.975852
Juan A. Marin-Garciaa* & Tomas Bonaviab
Received: 1 Aug 2013
Accepted: 30 Sep 2014
Published online: 04 Nov 2014
This research aims to empirically test the effect of employee involvement on lean manufacturing (LM), and the effect of LM on production outcomes. Employee involvement is operationalised through four related variables: empowerment, training, contingent remuneration and communication. The effects are tested by recording management perceptions in a different industrial sector from those usually studied in previous research ceramic manufacturers, a highly competitive and internationally successful sector. We obtained data from 101 ceramic tile plants (64% of response rate) in the Valencia region of Spain. This approach is developed using a statistical method called partial least squares. All paths are significant except for contingent remuneration; specifically, relationships were found between empowerment, training, communication and LM, and between LM and performance.This paper has been written with financial support from the Project "Path Dependence and decision-making for selecting LM tools and practices" (PAID-06-12-SP20120717) of the Universitat Politecnica de Valencia.MarÃn GarcÃa, JA.; BonavÃa MartÃn, T. (2015). Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry. International Journal of Production Research. 53(11):3260-3275. https://doi.org/10.1080/00207543.2014.975852S32603275531
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