1,088 research outputs found
Evaluating irreversible social harms
In this paper we investigate how irreversible social harms should be evaluated from an ethical perspective. First, we define a general notion of irreversibility, drawing on discussions in ecology and economics. This notion is relational in the sense that 'irreversibility' is always 'irreversibility for a certain party'. We also note that a change may be more or less difficult to reverse, with full reversibility and irreversibility as two extremes. Second, we examine what can make an irreversible change a harm, and why these kinds of harms have particular ethical significance. Here we draw on discussions from ethics, particularly regarding the Capability Approach. We also show how our notion of irreversibility connects to, and can add to, discussions in the fields of development studies and disaster management, particularly on the concept of resilience. Third, we suggest how potentially irreversible harms can be recognised and dealt with in policy-making. Finally, we show how our framework can be applied by evaluating the land acquisition process of two biofuel producers in Tanzania
Ageing effects around the glass and melting transitions in poly(dimethylsiloxane) visualized by resistance measurements
The process of ageing in rubbers requires monitoring over long periods (days
to years). To do so in non-conducting rubbers, small amounts of carbon-black
particles were dispersed in a fractal network through the rubber matrix, to
make the rubber conducting without modifying its properties. Continuous
monitoring of the resistance reveals the structural changes around the glass
and melting transitions and especially details about the hysteresis and ageing
processes. We illustrate the method for the semicrystalline polymer
poly(dimethylsiloxane) (PDMS).Comment: 4 pages, 4 figure
How to assess the external validity of therapeutic trials: a conceptual approach
Background External validity of study results is an important issue from a clinical point of view. From a methodological point of view, however, the concept of external validity is more complex than it seems to be at first glance. Methods Methodological review to address the concept of external validity. Results External validity refers to the question whether results are generalizable to persons other than the population in the original study. The only formal way to establish the external validity would be to repeat the study for that specific target population. We propose a three-way approach for assessing the external validity for specified target populations. (i) The study population might not be representative for the eligibility criteria that were intended. It should be addressed whether the study population differs from the intended source population with respect to characteristics that influence outcome. (ii) The target population will, by definition, differ from the study population with respect to geographical, temporal and ethnical conditions. Pondering external validity means asking the question whether these differences may influence study results. (iii) It should be assessed whether the study's conclusions can be generalized to target populations that do not meet all the eligibility criteria. Conclusion Judging the external validity of study results cannot be done by applying given eligibility criteria to a single target population. Rather, it is a complex reflection in which prior knowledge, statistical considerations, biological plausibility and eligibility criteria all have plac
Lipolytic sensitivity to catecholamines in patients with human immunodeficiency virus infection
Lipolysis is higher in patients with acquired immunodeficiency syndrome (AIDS) than in healthy control subjects. To evaluate whether this increase in lipolysis is related to increased beta-adrenergic sensitivity, we compared the lipolytic response to epinephrine (approximately 15 ng x kg(-1) x min(-1)) of six AIDS patients with that of six matched control subjects. Lipolysis was measured by infusion of [2H2]glycerol and [2H2]palmitate. The baseline rates of appearance of palmitate (2.06 +/- 0.21 compared with 1.45 +/- 0.07 micromol x kg(-1) x min(-1)) and glycerol (2.35 +/- 0.16 compared with 1.35 +/- 0.06 micromol x kg(-1) x min(-1)) were higher in AIDS patients (P <0.05). The absolute increase in lipolysis, an indicator of the responsiveness to epinephrine, was not different between groups for the rate of appearance of palmitate (86 +/- 14 compared with 75 +/- 7 micromol x L(-1) x min(-1)) or glycerol (79 +/- 13 compared with 59 +/- 6 micromol x L(-1) x min(-1)). Plasma concentrations of epinephrine were not different between groups. Lipolysis was higher whereas the lipolytic response to epinephrine was normal in AIDS patients. Increased lipolytic sensitivity to catecholamines is not the cause of increased lipolysis in AID
Dissolution of metal precipitates in multicrystalline silicon during annealing and the protective effect of phosphorus emitters
The degradation of the carrier lifetime in multicrystalline silicon due to the dissolution of metal precipitates during high temperature annealing is well known. This letter presents evidence indicating that the presence of phosphorus emitters during annealing can help reduce this recontamination. Part of the degradation observed is due to increased interstitial iron concentrations caused by the dissolution of iron precipitates during annealing. However, dissolution of other metals also seems to contribute to the reduced carrier lifetimes observed.The authors would like to acknowledge the Australian
Research Council for funding this work
An impact assessment methodology for small scale renewable energy projects in developing countries funded under Dutch policies defined to contribute to the millennium development goals
Vulnerable groups, such as poor people in developing countries, are often hit
hard by the effects of climate change since they lack the resources needed to
cope or adapt to the changing environment. To conduct poverty reduction
without compromising on the environment, the Dutch government defined a
variety of policy measures. One is the soâcalled Daey Ouwens Fund, established
to implement small scale renewable energy projects in the poorest countries of
the world. This Fund aims to contribute to Millennium Developing Goal 1,
eradication of extreme poverty, and MDG 7, ensuring environmental
sustainability. This paper describes the methodology developed to get a better
understanding of the socioeconomic and environmental impact of projects to be
implemented under the Daey Ouwens Fund. This methodology uses the multi level
âStrategic Niche Management (SNM)â framework to systematically assess drivers
and barriers crucial in process of innovation. For three selected projects,
indicators are defined within this SNM framework, based on the MGD 1 and MGD 7
and the local socioâeconomic situation as well as the existing energy system
and the innovative renewable energy technology of the project. These
indicators are translated into sets of questions to be quantified through a
limited number of semiâstructured interviews with key persons and
questionnaire inquiries of a large number of potential endâusers. The data of
the conducted baseline study will be presented in this paper to provide an
overall picture of the current socioâeconomic situation and the energy
consumption in the areas were the three selected project are going to be
implemented. Based on these data and the SNM framework, an overview will be
provided of drivers and barriers for the projects and the expected
contribution to MDG 1 and 7. The methodology will be assessed and adapted for
the impact monitoring assessment that will be held in 2013
Governed by history: Institutional analysis of a contested biofuel innovation system in Tanzania
Initially hailed as a miracle crop for biofuel production, Jatropha has recently attracted criticism for competing with food production, causing adverse biodiversity impacts, and jeopardizing land access by rural populations in tropical countries. This paper analyzes the contested development of Jatropha biofuel sector in Tanzania by anchoring two new concepts of âorganizational modelsâ and âinstitutional arrangementsâ to the sectoral systems of innovation perspective. The notion of âorganizational modelsâ brings into relief the heterogeneity of actors in an innovation system and the ways in which the actors form networks, within and across national borders, to organize innovative activities. The concept of âinstitutional arrangementsâ refers to the ensemble of formal and informal institutions assembled during Tanzaniaâs colonial and post-colonial eras, which directly govern innovative activities in specific organizational models. Based on a location-specific and historically-grounded institutional analysis within the innovation system framework, implications are drawn for the future development of Tanzaniaâs Jatropha sector including its links with European markets and for the regulation of ânext-generationâ biofuels
Purification of Parvalbumin from Carp: A Protocol That Avoids Heat Treatment
Parvalbumin from carp, a major allergen,was purified to homogeneity using ion exchange chromatography and size exclusion chromatography (estimated purity \u3e 95% to 98% based on SDS-PAGE and native PAGE) with a yield of 318 mg, and a number of basic biochemical characteristics were determined. The identity was confirmed by peptide-mass fingerprinting, and IgE-binding was demonstrated. The UV/Vis absorbance spectra were explained using the previously published amino acid sequences. Far UV-CD spectroscopy was used to confirm the folding character of parvalbumin. We conclude that parvalbumin from carp can be purified on a comparatively large (hundreds of milligrams) scale using a purification protocol that does not include denaturing steps. The purified protein resembles biochemical characteristics as were earlier published for carp parvalbumin, that is, a molecular weight of approximately 12 kDa, amino acid sequence identity and a secondary structure containing α-helices and ÎČ-structures. The described method provides a yield sufficient to produce and characterize antibodies to construct immunochemical methods to detect parvalbumin in food as well as for use as a standard calibrator for such assays.
Practical Application: Parvalbumin is a major allergen from fish. Here,we have purified a comparatively large quantity from carp that can be used to develop antisera for use in an assay method to detect fish allergens
Depairing currents in the superconductor/ferromagnet proximity system Nb/Fe
We have investigated the behaviour of the depairing current J_{dp} in
ferromagnet/superconductor/ferromagnet (F/S/F) trilayers as function of the
thickness d_s of the superconducting layers. Theoretically, J_{dp} depends on
the superconducting order parameter or the pair density function, which is not
homogeneous across the film due to the proximity effect. We use a proximity
effect model with two parameters (proximity strength and interface
transparency), which can also describe the dependence of the superconducting
transition temperature T_c on d_s. We compare the computations with the
experimentally determined zero-field critical current J_{c0} of small strips
(typically 5~ \mu m wide) of Fe/Nb/Fe trilayers with varying thickness d_{Nb}
of the Nb layer. Near T_c the temperature dependence J_{c0}(T) is in good
agreement with the expected behaviour, which allows extrapolation to T = 0.
Both the absolute values of J_{c0}(0) and the dependence on d_{Nb} agree with
the expectations for the depairing current. We conclude that J_{dp} is
correctly determined, notwithstanding the fact that the strip width is larger
than both the superconducting penetration depth and the superconducting
coherence length, and that J_{dp}(d_s) is correctly described by the model.Comment: 10 pages, 5 figures, submitted to PR
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