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Distributional Aspects of Microcredit Expansions
Various poverty reduction strategies are being implemented in the pursuit of eliminating extreme poverty. One such strategy is increased access to microcredit in poor areas around the world. Microcredit, typically defined as the supply of small loans to underserved entrepreneurs that originally aimed at displacing expensive local money-lenders, has been both praised and criticized as a development tool Banerjee et al. (2015c). This paper presents an analysis of heterogeneous impacts from increased access to microcredit using data from three randomised trials. In the spirit of recognising that in general the impact of a policy intervention varies conditional on an unknown set of factors, particular, we investigate whether heterogeneity presents itself as groups of winners and losers, and whether such subgroups share characteristics across RCTs. We find no evidence of impacts, neither average nor distributional, from increased access to microcredit on consumption levels. In contrast, the lack of average effects on profits seems to mask heterogeneous impacts. The findings are, however, not robust to the specific machine learning algorithm applied. Switching from the better performing Elastic Net to the worse performing Random Forest leads to a sharp increase in the variance of the estimates. In this context, methods to evaluate the relative performing machine learning algorithm developed by Chernozhukov et al. (2019) provide a disciplined way for the analyst to counter the uncertainty as to which algorithm to deploy
The shape of equality: discourses around the Section 28 repeal in Scotland
This article focuses on conceptualizations of equality in the discourses deployed in the campaign to repeal Section 28 in Scotland. I use the parliamentary debates and two newspapers: the Daily Record, which supported the campaign to Keep the Clause, and The Guardian, which supported repeal, to exemplify the different discursive articulations around equality and citizenship. I suggest that the Scottish example provides further evidence of the ways in which liberalism naturalizes heterosexuality as the standard for citizenship and thus bequeaths a hierarchy of 'equality' and citizenship in the realm of sexuality, wherein lesbian and gay citizenship is either rendered invalid or characterized as 'special rights'. However, within the narrow confines of the parliamentary debates, more expansive and differentiated notions of citizenship and equality are evident. Whilst I conclude that the 'shape' of equality achieved through the repeal has been moulded to support institutionalized heterosexuality - with Section 28 replaced by statutory guidelines on sex education which advocate marriage - I also suggest equality is contested, both through the recognition of transformations in heterosexual family forms and the appeal to non-discrimination as a democratic principle. It is possible, therefore, that current destabilizations of the heterosexual social order simultaneously destabilize the precepts of liberal democracy
Vortex jamming in superconductors and granular rheology
We demonstrate that a highly frustrated anisotropic Josephson junction
array(JJA) on a square lattice exhibits a zero-temperature jamming transition,
which shares much in common with those in granular systems. Anisotropy of the
Josephson couplings along the horizontal and vertical directions plays roles
similar to normal load or density in granular systems. We studied numerically
static and dynamic response of the system against shear, i. e. injection of
external electric current at zero temperature. Current-voltage curves at
various strength of the anisotropy exhibit universal scaling features around
the jamming point much as do the flow curves in granular rheology, shear-stress
vs shear-rate. It turns out that at zero temperature the jamming transition
occurs right at the isotropic coupling and anisotropic JJA behaves as an exotic
fragile vortex matter : it behaves as superconductor (vortex glass) into one
direction while normal conductor (vortex liquid) into the other direction even
at zero temperature. Furthermore we find a variant of the theoretical model for
the anisotropic JJA quantitatively reproduces universal master flow-curves of
the granular systems. Our results suggest an unexpected common paradigm
stretching over seemingly unrelated fields - the rheology of soft materials and
superconductivity.Comment: 10 pages, 5 figures. To appear in New Journal of Physic
Segue Between Favorable and Unfavorable Solvation
Solvation of small and large clusters are studied by simulation, considering
a range of solvent-solute attractive energy strengths. Over a wide range of
conditions, both for solvation in the Lennard-Jones liquid and in the SPC model
of water, it is shown that the mean solvent density varies linearly with
changes in solvent-solute adhesion or attractive energy strength. This behavior
is understood from the perspective of Weeks' theory of solvation [Ann. Rev.
Phys. Chem. 2002, 53, 533] and supports theories based upon that perspective.Comment: 8 pages, 7 figure
Structural relaxation of E' gamma centers in amorphous silica
We report experimental evidence of the existence of two variants of the E'
gamma centers induced in silica by gamma rays at room temperature. The two
variants are distinguishable by the fine features of their line shapes in
paramagnetic resonance spectra. These features suggest that the two E' gamma
differ for their topology. We find a thermally induced interconversion between
the centers with an activation energy of about 34 meV. Hints are also found for
the existence of a structural configuration of minimum energy and of a
metastable state.Comment: 4 pages, 2 figures, submitted to Phys. Rev. Let
Nature of phase transition(s) in striped phase of triangular-lattice Ising antiferromagnet
Different scenarios of the fluctuation-induced disordering of the striped
phase which is formed at low temperatures in the triangular-lattice Ising model
with the antiferromagnetic interaction of nearest and next-to-nearest neighbors
are analyzed and compared. The dominant mechanism of the disordering is related
to the formation of a network of domain walls, which is characterized by an
extensive number of zero modes and has to appear via the first-order phase
transition. In principle, this first-order transition can be preceded by a
continuous one, related to the spontaneous formation of double domain walls and
a partial restoration of the broken symmetry, but the realization of such a
scenario requires the fulfillment of rather special relations between the
coupling constants.Comment: 10 pages, 7 figures, ReVTeX
SHAPE-directed RNA secondary structure prediction
The diverse functional roles of RNA are determined by its underlying structure. Accurate and comprehensive knowledge of RNA structure would inform a broader understanding of RNA biology and facilitate exploiting RNA as a biotechnological tool and therapeutic target. Determining the pattern of base pairing, or secondary structure, of RNA is a first step in these endeavors. Advances in experimental, computational, and comparative analysis approaches for analyzing secondary structure have yielded accurate structures for many small RNAs, but only a few large (>500 nts) RNAs. In addition, most current methods for determining a secondary structure require considerable effort, analytical expertise, and technical ingenuity. In this review, we outline an efficient strategy for developing accurate secondary structure models for RNAs of arbitrary length. This approach melds structural information obtained using SHAPE chemistry with structure prediction using nearest-neighbor rules and the dynamic programming algorithm implemented in the RNAstructure program. Prediction accuracies reach ≥95% for RNAs on the kilobase scale. This approach facilitates both development of new models and refinement of existing RNA structure models, which we illustrate using the Gag-Pol frameshift element in an HIV-1 M-group genome. Most promisingly, integrated experimental and computational refinement brings closer the ultimate goal of efficiently and accurately establishing the secondary structure for any RNA sequence
An Exploratory Discussion of Online Game as Computing Entertainment: Esport Perspectives Using Mobile Gaming Devices
This study aims to develop implications for the future development of Japanese eSports. A mixed method was applied including survey data and in-depth interview data collected from Japanese online game stakeholders. The greatest contribution of this research is an in-depth study of the future prospects of eSports in Japan using primary data. This has been lacking in previous discussions, which have not been able to submit clear proposals. This study also suggests a different development path for media entertainment towards a trinity that includes players, spectators and viewers on virtual video sharing platforms, as is the case in the advanced eSports countries of Europe, the US, China and Korea. In terms of strategy development, there is clear indication that a Japanese-style model should be pursued, drawing on Japan’s unique background and strengths
Are Bone and Muscle Changes from POWER PE, an 8-month In-school Jumping Intervention, Maintained at Three Years?
Our aim was to determine if the musculoskeletal benefits of a twice-weekly, school-based, jumping regime in healthy adolescent boys and girls were maintained three years later. Subjects of the original POWER PE trial (n = 99) were contacted and asked to undergo retesting three years after cessation of the intervention. All original measures were completed including: sitting height, standing height, weight, calcaneal broadband ultrasound attenuation (BUA), whole body, hip and spine bone mineral content (BMC), lean tissue mass, and fat mass. Physical activity was recorded with the bone-specific physical activity questionnaire (BPAQ) and calcium intake was estimated with a calcium-focussed food questionnaire. Maturity was determined by Tanner staging and estimation of the age of peak height velocity (PHV). Twenty-nine adolescents aged 17.3±0.4 years agreed to participate. Three years after the intervention, there were no differences in subject characteristics between control and intervention groups (p>0.05). Three-year change in weight, lean mass, and fat mass were similar between groups (p>0.05). There were no significant group differences in three-year change in BUA or BMC at any site (p>0.05), although the between-group difference in femoral neck BMC at follow-up exceeded the least significant change. While significant group differences were not observed three years after cessation of the intervention, changes in bone parameters occurred in parallel for intervention and control groups such that the original benefits of the intervention observed within the treatment group were sustained
Roughening Transition of Interfaces in Disordered Systems
The behavior of interfaces in the presence of both lattice pinning and random
field (RF) or random bond (RB) disorder is studied using scaling arguments and
functional renormalization techniques. For the first time we show that there is
a continuous disorder driven roughening transition from a flat to a rough state
for internal interface dimensions 2<D<4. The critical exponents are calculated
in an \epsilon-expansion. At the transition the interface shows a
superuniversal logarithmic roughness for both RF and RB systems. A transition
does not exist at the upper critical dimension D_c=4. The transition is
expected to be observable in systems with dipolar interactions by tuning the
temperature.Comment: 4 pages, RevTeX, 1 postscript figur
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