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Discovering Communities through Friendship
We introduce a new method for detecting communities of arbitrary size in an undirected weighted network. Our approach is based on tracing the path of closest‐friendship between nodes in the network using the recently proposed Generalized Erds Numbers. This method does not require the choice of any arbitrary parameters or null models, and does not suffer from a system‐size resolution limit. Our closest‐friend community detection is able to accurately reconstruct the true network structure for a large number of real world and artificial benchmarks, and can be adapted to study the multi‐level structure of hierarchical communities as well. We also use the closeness between nodes to develop a degree of robustness for each node, which can assess how robustly that node is assigned to its community. To test the efficacy of these methods, we deploy them on a variety of well known benchmarks, a hierarchal structured artificial benchmark with a known community and robustness structure, as well as real‐world networks of coauthorships between the faculty at a major university and the network of citations of articles published in Physical Review. In all cases, microcommunities, hierarchy of the communities, and variable node robustness are all observed, providing insights into the structure of the network.Engineering and Applied SciencesPhysic
Practical guide to glucocorticoid induced hyperglycaemia and diabetes
Glucocorticoids, also known as steroids, are a class of anti-inflammatory drugs utilised widely in clinical practice for a variety of conditions. They are associated with a range of side effects including abnormalities of glucose metabolism. Multiple guidelines have been published to illustrate best management of glucocorticoid-induced hyperglycaemia and diabetes in a variety of settings. This article discusses current best clinical practice including diagnosis, investigations and ongoing management of glucocorticoid-induced dysglycaemia in both in- and outpatient settings
Genetic improvements to the sterile insect technique for agricultural pests
The sterile insect technique (SIT) relies on area-wide mass-releases of sterile male pest insects, which mate with their wild counterparts and thereby cause a drop in the wild population. In order to improve SIT efficacy or to avoid potential negative effects of such releases, strains of insects have been developed by genetic means. Methods of strain improvement fall into two categories: those generated by classical genetics and those through transgenesis. Here, we describe development and successes of agriculturally important pest insect strains developed through the former, and how transgenic technology is offering a broad spectrum of potential improvements to SIT in a wider range of insects. Also discussed are future prospects and non-technical challenges faced by transgenic technology. The need for environment-friendly pest control methods in agriculture has never been more pressing. SIT and related technologies offer a solution with proven effectiveness
Fivebrane Instantons and couplings in String Theory
We compute the gravitational coupling for IIA string theory on and use string-string duality to deduce the corresponding term for
heterotic string on . The latter is an infinite sum of gravitational
instanton effects which we associate with the effects of Euclidean fivebranes
wrapped on . These fivebranes are the neutral fivebranes or zero size
instantons of heterotic string theory.Comment: 16 pages, harvmac, no figure
Wet scavenging of soluble gases in DC3 deep convective storms using WRF-Chem simulations and aircraft observations
We examine wet scavenging of soluble trace gases in storms observed during the Deep Convective Clouds and Chemistry (DC3) field campaign. We conduct high-resolution simulations with the Weather Research and Forecasting model with Chemistry (WRF-Chem) of a severe storm in Oklahoma. The model represents well the storm location, size, and structure as compared with Next Generation Weather Radar reflectivity, and simulated CO transport is consistent with aircraft observations. Scavenging efficiencies (SEs) between inflow and outflow of soluble species are calculated from aircraft measurements and model simulations. Using a simple wet scavenging scheme, we simulate the SE of each soluble species within the error bars of the observations. The simulated SEs of all species except nitric acid (HNO_3) are highly sensitive to the values specified for the fractions retained in ice when cloud water freezes. To reproduce the observations, we must assume zero ice retention for formaldehyde (CH_2O) and hydrogen peroxide (H_2O_2) and complete retention for methyl hydrogen peroxide (CH_3OOH) and sulfur dioxide (SO_2), likely to compensate for the lack of aqueous chemistry in the model. We then compare scavenging efficiencies among storms that formed in Alabama and northeast Colorado and the Oklahoma storm. Significant differences in SEs are seen among storms and species. More scavenging of HNO_3 and less removal of CH_3OOH are seen in storms with higher maximum flash rates, an indication of more graupel mass. Graupel is associated with mixed-phase scavenging and lightning production of nitrogen oxides (NO_x), processes that may explain the observed differences in HNO_3 and CH_3OOH scavenging
Finite-Temperature Fractional D2-Branes and the Deconfinement Transition in 2+1 Dimensions
The supergravity dual to N regular and M fractional D2-branes on the cone
over \mathbb{CP}^3 has a naked singularity in the infrared. One can resolve
this singularity and obtain a regular fractional D2-brane solution dual to a
confining 2+1 dimensional N = 1 supersymmetric field theory. The confining
vacuum of this theory is described by the solution of Cvetic, Gibbons, Lu and
Pope. In this paper, we explore the alternative possibility for resolving the
singularity - the creation of a regular horizon. The black-hole solution we
find corresponds to the deconfined phase of this dual gauge theory in three
dimensions. This solution is derived in perturbation theory in the number of
fractional branes. We argue that there is a first-order deconfinement
transition. Connections to Chern--Simons matter theories, the ABJM proposal and
fractional M2-branes are presented.Comment: v3: analytic solutions are expose
Mechanisms controlling anaemia in Trypanosoma congolense infected mice.
Trypanosoma congolense are extracellular protozoan parasites of the blood stream of artiodactyls and are one of the main constraints on cattle production in Africa. In cattle, anaemia is the key feature of disease and persists after parasitaemia has declined to low or undetectable levels, but treatment to clear the parasites usually resolves the anaemia. The progress of anaemia after Trypanosoma congolense infection was followed in three mouse strains. Anaemia developed rapidly in all three strains until the peak of the first wave of parasitaemia. This was followed by a second phase, characterized by slower progress to severe anaemia in C57BL/6, by slow recovery in surviving A/J and a rapid recovery in BALB/c. There was no association between parasitaemia and severity of anaemia. Furthermore, functional T lymphocytes are not required for the induction of anaemia, since suppression of T cell activity with Cyclosporin A had neither an effect on the course of infection nor on anaemia. Expression of genes involved in erythropoiesis and iron metabolism was followed in spleen, liver and kidney tissues in the three strains of mice using microarrays. There was no evidence for a response to erythropoietin, consistent with anaemia of chronic disease, which is erythropoietin insensitive. However, the expression of transcription factors and genes involved in erythropoiesis and haemolysis did correlate with the expression of the inflammatory cytokines Il6 and Ifng. The innate immune response appears to be the major contributor to the inflammation associated with anaemia since suppression of T cells with CsA had no observable effect. Several transcription factors regulating haematopoiesis, Tal1, Gata1, Zfpm1 and Klf1 were expressed at consistently lower levels in C57BL/6 mice suggesting that these mice have a lower haematopoietic capacity and therefore less ability to recover from haemolysis induced anaemia after infection
Community-associated Methicillin-resistant Staphylococcus aureus and Healthcare Risk Factors
To determine frequency of methicillin-resistant Staphylococcus aureus infections caused by strains typically associated with community-acquired infections (USA300) among persons with healthcare-related risk factors (HRFs), we evaluated surveillance data. Of patients with HRFs, 18%–28% had a "community-associated" strain, primarily USA300; of patients without HRFs, 26% had a "healthcare-associated" strain, typically USA100
Prostate Cancer Risk by BRCA2 Genomic Regions.
A BRCA2 prostate cancer cluster region (PCCR) was recently proposed (c.7914 to 3') wherein pathogenic variants (PVs) are associated with higher prostate cancer (PCa) risk than PVs elsewhere in the BRCA2 gene. Using a prospective cohort study of 447 male BRCA2 PV carriers recruited in the UK and Ireland from 1998 to 2016, we estimated standardised incidence ratios (SIRs) compared with population incidences and assessed variation in risk by PV location. Carriers of PVs in the PCCR had a PCa SIR of 8.33 (95% confidence interval [CI] 4.46-15.6) and were at a higher risk of PCa than carriers of other BRCA2 PVs (SIR = 3.31, 95% CI 1.97-5.57; hazard ratio = 2.34, 95% CI 1.09-5.03). PCCR PV carriers had an estimated cumulative PCa risk of 44% (95% CI 23-72%) by the age of 75 yr and 78% (95% CI 54-94%) by the age of 85 yr. Our results corroborate the existence of a PCCR in BRCA2 in a prospective cohort. PATIENT SUMMARY: In this report, we investigated whether the risk of prostate cancer for men with a harmful mutation in the BRCA2 gene differs based on where in the gene the mutation is located. We found that men with mutations in one region of BRCA2 had a higher risk of prostate cancer than men with mutations elsewhere in the gene
Maternal feeding practices and fussy eating in toddlerhood: A discordant twin analysis
Background: Parental feeding practices are thought to play a causal role in shaping a child's fussiness; however, a child-responsive model suggests that feeding practices may develop in response to a child's emerging appetitive characteristics. We used a novel twin study design to test the hypothesis that mothers vary their feeding practices for twin children who differ in their 'food fussiness', in support of a child-responsive model. Methods: Participants were mothers and their 16 month old twin children (n=2026) from Gemini, a British twin birth cohort of children born in 2007. Standardized psychometric measures of maternal 'pressure to eat', 'restriction' and 'instrumental feeding', as well as child 'food fussiness', were completed by mothers. Within-family analyses examined if twin-pair differences in 'food fussiness' were associated with differences in feeding practices using linear regression models. In a subset of twins (n=247 pairs) who were the most discordant (highest quartile) on 'food fussiness' (difference score≥.50), Paired Samples T-test were used to explore the magnitude of differences in feeding practices between twins. Between-family analyses used Complex Samples General Linear Models to examine associations between feeding practices and 'food fussiness'. Results: Within-pair differences in 'food fussiness' were associated with differential 'pressure to eat' and 'instrumental feeding' (ps<.001), but not with 'restriction'. In the subset of twins most discordant on 'food fussiness', mothers used more pressure (p<.001) and food rewards (p<.05) with the fussier twin. Between-family analyses indicated that 'pressure to eat' and 'instrumental feeding' were positively associated with 'food fussiness', while 'restriction' was negatively associated with 'food fussiness' (ps<.001). Conclusions: Mothers appear to subtly adjust their feeding practices according to their perceptions of their toddler's emerging fussy eating behavior. Specifically, the fussier toddler is pressured more than their less fussy co-twin, and is more likely to be offered food rewards. Guiding parents on how to respond to fussy eating may be an important aspect of promoting feeding practices that encourage food acceptance
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