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Gentian violet for pyoderma gangrenosum: a retrospective chart review
Pyoderma gangrenosum is a rare autoinflammatory skin disease. Treatment is multifactorial, addressing inflammation, pain, underlying disease, if present, and the wound. Gentian violet has been used for hundreds of years in a variety of dermatologic conditions for its anti-inflammatory properties. This study aims to evaluate gentian violet in wound healing for pyoderma gangrenosum. We conducted a retrospective chart review of patients with pyoderma gangrenosum treated with gentian violet at the Wake Forest School of Medicine Department of Dermatology in the last 10 years. The primary outcome was clinical improvement. Of the 34 cases that met inclusion criteria, 70% improved with gentian violet, 24% had no documented change, 3% initially improved then worsened, and 3% had unclear results. Gentian violet is a safe and cheap treatment that may improve resolution of pyoderma gangrenosum lesions in addition to systemic therapy
Measures of genetic diversification in somatic tissues at bulk and single-cell resolution.
Intra-tissue genetic heterogeneity is universal to both healthy and cancerous tissues. It emerges from the stochastic accumulation of somatic mutations throughout development and homeostasis. By combining population genetics theory and genomic information, genetic heterogeneity can be exploited to infer tissue organization and dynamics in vivo. However, many basic quantities, for example the dynamics of tissue-specific stem cells remain difficult to quantify precisely. Here, we show that single-cell and bulk sequencing data inform on different aspects of the underlying stochastic processes. Bulk-derived variant allele frequency spectra (VAF) show transitions from growing to constant stem cell populations with age in samples of healthy esophagus epithelium. Single-cell mutational burden distributions allow a sample size independent measure of mutation and proliferation rates. Mutation rates in adult hematopietic stem cells are higher compared to inferences during development, suggesting additional proliferation-independent effects. Furthermore, single-cell derived VAF spectra contain information on the number of tissue-specific stem cells. In hematopiesis, we find approximately 2 Ă— 105 HSCs, if all stem cells divide symmetrically. However, the single-cell mutational burden distribution is over-dispersed compared to a model of Poisson distributed random mutations. A time-associated model of mutation accumulation with a constant rate alone cannot generate such a pattern. At least one additional source of stochasticity would be needed. Possible candidates for these processes may be occasional bursts of stem cell divisions, potentially in response to injury, or non-constant mutation rates either through environmental exposures or cell-intrinsic variation
SOXE neofunctionalization and elaboration of the neural crest during chordate evolution
During chordate evolution, two genome-wide duplications facilitated acquisition of vertebrate traits, including emergence of neural crest cells (NCCs), in which neofunctionalization of the duplicated genes are thought to have facilitated development of craniofacial structures and the peripheral nervous system. How these duplicated genes evolve and acquire the ability to specify NC and their derivatives are largely unknown. Vertebrate SoxE paralogues, most notably Sox9/10, are essential for NC induction, delamination and lineage specification. In contrast, the basal chordate, amphioxus, has a single SoxE gene and lacks NC-like cells. Here, we test the hypothesis that duplication and divergence of an ancestral SoxE gene may have facilitated elaboration of NC lineages. By using an in vivo expression assay to compare effects of AmphiSoxE and vertebrate Sox9 on NC development, we demonstrate that all SOXE proteins possess similar DNA binding and homodimerization properties and can induce NCCs. However, AmphiSOXE is less efficient than SOX9 in transactivation activity and in the ability to preferentially promote glial over neuronal fate, a difference that lies within the combined properties of amino terminal and transactivation domains. We propose that acquisition of AmphiSoxE expression in the neural plate border led to NCC emergence while duplication and divergence produced advantageous mutations in vertebrate homologues, promoting elaboration of NC traits.published_or_final_versio
Lorentz-Violating Supergravity
The standard forms of supersymmetry and supergravity are inextricably wedded
to Lorentz invariance. Here a Lorentz-violating form of supergravity is
proposed. The superpartners have exotic properties that are not possible in a
theory with exact Lorentz symmetry and microcausality. For example, the bosonic
sfermions have spin 1/2 and the fermionic gauginos have spin 1. The theory is
based on a phenomenological action that is shown to follow from a simple
microscopic and statistical picture.Comment: 15 pages; to be published in Proceedings of Beyond the Desert 2003
(Castle Ringberg, Tegernsee, Germany, 9-14 June 2003), edited by H. V.
Klapdor-Kleingrothau
ForestHash: Semantic Hashing With Shallow Random Forests and Tiny Convolutional Networks
Hash codes are efficient data representations for coping with the ever
growing amounts of data. In this paper, we introduce a random forest semantic
hashing scheme that embeds tiny convolutional neural networks (CNN) into
shallow random forests, with near-optimal information-theoretic code
aggregation among trees. We start with a simple hashing scheme, where random
trees in a forest act as hashing functions by setting `1' for the visited tree
leaf, and `0' for the rest. We show that traditional random forests fail to
generate hashes that preserve the underlying similarity between the trees,
rendering the random forests approach to hashing challenging. To address this,
we propose to first randomly group arriving classes at each tree split node
into two groups, obtaining a significantly simplified two-class classification
problem, which can be handled using a light-weight CNN weak learner. Such
random class grouping scheme enables code uniqueness by enforcing each class to
share its code with different classes in different trees. A non-conventional
low-rank loss is further adopted for the CNN weak learners to encourage code
consistency by minimizing intra-class variations and maximizing inter-class
distance for the two random class groups. Finally, we introduce an
information-theoretic approach for aggregating codes of individual trees into a
single hash code, producing a near-optimal unique hash for each class. The
proposed approach significantly outperforms state-of-the-art hashing methods
for image retrieval tasks on large-scale public datasets, while performing at
the level of other state-of-the-art image classification techniques while
utilizing a more compact and efficient scalable representation. This work
proposes a principled and robust procedure to train and deploy in parallel an
ensemble of light-weight CNNs, instead of simply going deeper.Comment: Accepted to ECCV 201
Exploiting Polyhedral Symmetries in Social Choice
A large amount of literature in social choice theory deals with quantifying
the probability of certain election outcomes. One way of computing the
probability of a specific voting situation under the Impartial Anonymous
Culture assumption is via counting integral points in polyhedra. Here, Ehrhart
theory can help, but unfortunately the dimension and complexity of the involved
polyhedra grows rapidly with the number of candidates. However, if we exploit
available polyhedral symmetries, some computations become possible that
previously were infeasible. We show this in three well known examples:
Condorcet's paradox, Condorcet efficiency of plurality voting and in Plurality
voting vs Plurality Runoff.Comment: 14 pages; with minor improvements; to be published in Social Choice
and Welfar
Consenting to health record linkage: evidence from a multi-purpose longitudinal survey of a general population
Background: The British Household Panel Survey (BHPS) is the first long-running UK longitudinal survey with a non-medical focus and a sample covering the whole age range to have asked for permission to link to a range of administrative health records. This study determines whether informed consent led to selection bias and reflects on the value of the BHPS linked with health records for epidemiological research. Methods. Multivariate logistical regression is used, with whether the respondent gave consent to data linkage or not as the dependent variable. Independent variables were entered as four blocks; (i) a set of standard demographics likely to be found in most health registration data, (ii) a broader set of socio-economic characteristics, (iii) a set of indicators of health conditions and (iv) information about the use of health services. Results: Participants aged 16-24, males and those living in England were more likely to consent. Consent is not biased with respect to socio-economic characteristics or health. Recent users of GP services are underrepresented among consenters. Conclusions: Whilst data could only be linked for a minority of BHPS participants, the BHPS offers a great range of information on people's life histories, their attitudes and behaviours making it an invaluable source for epidemiological research. © 2012 Knies et al; licensee BioMed Central Ltd
Learning Free-Form Deformations for 3D Object Reconstruction
Representing 3D shape in deep learning frameworks in an accurate, efficient
and compact manner still remains an open challenge. Most existing work
addresses this issue by employing voxel-based representations. While these
approaches benefit greatly from advances in computer vision by generalizing 2D
convolutions to the 3D setting, they also have several considerable drawbacks.
The computational complexity of voxel-encodings grows cubically with the
resolution thus limiting such representations to low-resolution 3D
reconstruction. In an attempt to solve this problem, point cloud
representations have been proposed. Although point clouds are more efficient
than voxel representations as they only cover surfaces rather than volumes,
they do not encode detailed geometric information about relationships between
points. In this paper we propose a method to learn free-form deformations (FFD)
for the task of 3D reconstruction from a single image. By learning to deform
points sampled from a high-quality mesh, our trained model can be used to
produce arbitrarily dense point clouds or meshes with fine-grained geometry. We
evaluate our proposed framework on both synthetic and real-world data and
achieve state-of-the-art results on point-cloud and volumetric metrics.
Additionally, we qualitatively demonstrate its applicability to label
transferring for 3D semantic segmentation.Comment: 16 pages, 7 figures, 3 table
Associations Between Parenting Styles and Perceived Child Effortful Control Within Chinese Families in the United States, the United Kingdom, and Taiwan
The current study examined the associations between parentally perceived child effortful control (EC) and the parenting styles of 122 Chinese mothers (36 first-generation Chinese immigrants in the United Kingdom, 40 first-generation Chinese immigrants in the United States, and 46 Taiwanese mothers) of 5- to 7-year-old (M age = 5.82 years, SD = .805; 68 boys and 54 girls) children. The findings showed significant cultural group differences in mothers’ reported authoritarian parenting style. Significant associations also emerged between mothers’ reports of their children’s EC and some parenting dimensions, although there were no cultural group differences in perceived child EC. Different patterns of associations between perceived child EC and parenting styles in these three groups also demonstrated heterogeneity within the Chinese population, and highlighted the need to consider differences between original and receiving societies when seeking to understand parenting and child development in different immigrant groups
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