890 research outputs found

    Strain Variation in the Transcriptome of the Dengue Fever Vector, Aedes aegypti

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    Studies of transcriptome dynamics provide a basis for understanding functional elements of the genome and the complexity of gene regulation. The dengue vector mosquito, Aedes aegypti, exhibits great adaptability to diverse ecological conditions, is phenotypically polymorphic, and shows variation in vectorial capacity to arboviruses. Previous genome sequencing showed richness in repetitive DNA and transposable elements that can contribute to genome plasticity. Population genetic studies revealed a varying degree of worldwide genetic polymorphism. However, the extent of functional genetic polymorphism across strains is unknown. The transcriptomes of three Ae. aegypti strains, Chetumal (CTM), Rexville D-Puerto Rico (Rex-D) and Liverpool (LVP), were compared. CTM is more susceptible than Rex- D to infection by dengue virus serotype 2. A total of 4188 transcripts exhibit either no or small variation (<2-fold) among sugar-fed samples of the three strains and between sugar- and blood-fed samples within each strain, corresponding most likely to genes encoding products necessary for vital functions. Transcripts enriched in blood-fed mosquitoes encode proteins associated with catalytic activities, molecular transport, metabolism of lipids, carbohydrates and amino acids, and functions related to blood digestion and the progression of the gonotropic cycle. Significant qualitative and quantitative differences were found in individual transcripts among strains including differential representation of paralogous gene products. The majority of immunity-associated transcripts decreased in accumulation after a bloodmeal and the results are discussed in relation to the different susceptibility of CTM and Rex-D mosquitoes to DENV2 infection

    Using mentoring to improve the foundation placement in psychiatry: review of literature and a practical example

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    In the past few years, mentoring in clinical settings has attracted the attention of medical educators, clinicians, managers, and policy makers. Most of the Royal Colleges of medical and surgical specialities have some form of mentoring schemes and various regional divisions of Health Education England support mentoring and coaching in the workplace. Despite the importance of this topic and the great need to provide more support to doctors in recent times, there is a paucity of literature on examples of mentoring schemes in clinical settings and practicalities of setting up such schemes in hospitals. This paper describes the implementation of a mentoring scheme in a large mental health trust in the UK to support junior doctors and the issues involved in creating such scheme. We hope that this article will be useful to clinicians who would like to start similar schemes in their workplace

    Naturalness and Focus Points with Non-Universal Gaugino Masses

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    Relations between the gaugino masses have been shown to alleviate the degree of fine-tuning in the MSSM. In this paper we consider specific models of supersymmetry breaking with gravity mediation and demonstrate that within both GUT and string constructions it is possible to generate these relations in a natural way. We have numerically studied the degree of fine-tuning in these models, including one-loop corrections, and have found regions of parameter space that can satisfy all known collider constraints with fine-tunings less than 20%. We discuss some of the phenomenological features of these models within the regions of reduced fine-tuning.Comment: 31 pages, 21 figures. Version accepted for publication in Nuclear Physics

    Implicit particle methods and their connection with variational data assimilation

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    The implicit particle filter is a sequential Monte Carlo method for data assimilation that guides the particles to the high-probability regions via a sequence of steps that includes minimizations. We present a new and more general derivation of this approach and extend the method to particle smoothing as well as to data assimilation for perfect models. We show that the minimizations required by implicit particle methods are similar to the ones one encounters in variational data assimilation and explore the connection of implicit particle methods with variational data assimilation. In particular, we argue that existing variational codes can be converted into implicit particle methods at a low cost, often yielding better estimates, that are also equipped with quantitative measures of the uncertainty. A detailed example is presented

    Identifying Dis/Misinformation on Social Media: A Policy Report for the Diplomacy Lab Strategies for Identifying Mis/Disinformation Project

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    Dis/misinformation was a major concern in the 2016 U.S. presidential election and has only worsened in recent years. Even though domestic actors often spread dis/misinformation, actors abroad can use it to spread confusion and push their agenda to the detriment of American citizens. Even though this report focuses on actors outside the United States, the methods they use are universal and can be adapted to work against domestic agents. A solid understanding of these methods is the first step in combating foreign dis/misinformation campaigns and creating a new information literacy paradigm. This report highlights the primary mechanisms of dis/misinformation: multimedia manipulation, bots, astroturfing, and trolling. These forms of dis/misinformation were selected after thorough research about common pathways dis/misinformation are spread online. Multimedia manipulation details image, video, and audio dis/misinformation in the form of deepfakes, memes, and out-of-context images. Bots are automated social media accounts that are not managed by humans and often contribute to dis/misinformation campaigns. Astroturfing and trolls use deception to sway media users to join false grassroots campaigns and utilize emotionally charged posts to provoke a response from users. This policy report also defines case studies of disinformation in China, Russia, and Iran, outlining common patterns of dis/misinformation specific to these countries. These patterns will allow for more accurate and quick identification of dis/misinformation from the outlined countries by State Department Watch Officers. Recommendations have also been provided for each type of disinformation and include a list of what individuals should look for and how to make sure that the information they receive is accurate and from a reputable source. The addendum at the end of the paper lists all of the recommendations in one place so that individuals do not have to search the paper for the recommendation they are looking for. This report intends to aid State Department Watch Officers as they work to identify foreign developments accurately. Still, researchers may find this information useful in anticipating future developments in foreign dis/misinformation campaigns

    Observational Constraints of Modified Chaplygin Gas in Loop Quantum Cosmology

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    We have considered the FRW universe in loop quantum cosmology (LQC) model filled with the dark matter (perfect fluid with negligible pressure) and the modified Chaplygin gas (MCG) type dark energy. We present the Hubble parameter in terms of the observable parameters Ωm0\Omega_{m0}, Ωx0\Omega_{x0} and H0H_{0} with the redshift zz and the other parameters like AA, BB, CC and α\alpha. From Stern data set (12 points), we have obtained the bounds of the arbitrary parameters by minimizing the χ2\chi^{2} test. The best-fit values of the parameters are obtained by 66%, 90% and 99% confidence levels. Next due to joint analysis with BAO and CMB observations, we have also obtained the bounds of the parameters (B,CB,C) by fixing some other parameters α\alpha and AA. From the best fit of distance modulus μ(z)\mu(z) for our theoretical MCG model in LQC, we concluded that our model is in agreement with the union2 sample data.Comment: 14 pages, 10 figures, Accepted in EPJC. arXiv admin note: text overlap with arXiv:astro-ph/0311622 by other author

    Determination of the exponent gamma for SAWs on the two-dimensional Manhattan lattice

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    We present a high-statistics Monte Carlo determination of the exponent gamma for self-avoiding walks on a Manhattan lattice in two dimensions. A conservative estimate is \gamma \gtapprox 1.3425(3), in agreement with the universal value 43/32 on regular lattices, but in conflict with predictions from conformal field theory and with a recent estimate from exact enumerations. We find strong corrections to scaling that seem to indicate the presence of a non-analytic exponent Delta < 1. If we assume Delta = 11/16 we find gamma = 1.3436(3), where the error is purely statistical.Comment: 24 pages, LaTeX2e, 4 figure

    Intraabdominal Cryptococcal Lymphadenitis in a Patient with Systemic Lupus Erythematosus

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    Cryptococcal infection is a rare, yet well recognized complication of systemic lupus erythematosus (SLE). We present a case of mesenteric and retroperitoneal cryptococcal lymphadenitis resulting in the obstruction of the stomach and proximal duodenum in a patient suffering from SLE, while recently she did not receive any immunosuppressive treatment. A 42-yr-old woman was admitted due to high fever and diffuse abdominal pain for three weeks. Abdominal computed tomography (CT) scan showed multiple conglomerated lymphadenopathies in the retroperitoneum and the mesentery resulting in luminal narrowing of the third portion of the duodenum. Cryptococcal lymphadenitis was proven by needle biopsy and she was treated with intravenous liposomal amphotericin B, followed by oral fluconazole. After fourteen-month antifungal therapies, the clinical symptoms and follow-up images improved. This case emphasize that the intrinsic immunological defects of SLE may be directly responsible for the predisposition to fungal infections

    Limits Due to Instrumental Polarisation in CMB Experiments at Microwave Wavelengths

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    An extended analysis of some instrumental polarisation sources has been done, as a consequence of the renewed interest in extremely sensitive polarisation measurements stimulated by Cosmic Microwave Background experiments. The case of correlation polarimeters, being them more suitable than other configurations, has been studied in detail and the algorithm has been derived to calculate their intrinsic sensitivity limit due to device characteristics as well as to the operating environment. The atmosphere emission, even though totally unpolarised, has been recognized to be the most important source of sensitivity degradation for ground based experiments. This happens through receiver component losses (mainly in the OMT), which generate instrumental polarisation in genuinely uncorrelated signals. The relevant result is that, also in best conditions (cfr. Antarctica), integration times longer than ~40s are not allowed on ground without modulation techniques. Finally, basic rules to estimate the maximum modulation period for each instrumental configuration have been provided.Comment: 20 pages, 5 postscript figures. Accepted for publication in New Astronomy (see http://www.elsevier.nl/locate/newast

    Resilin and chitinous cuticle form a composite structure for energy storage in jumping by froghopper insects

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    RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Many insects jump by storing and releasing energy in elastic structures within their bodies. This allows them to release large amounts of energy in a very short time to jump at very high speeds. The fastest of the insect jumpers, the froghopper, uses a catapult-like elastic mechanism to achieve their jumping prowess in which energy, generated by the slow contraction of muscles, is released suddenly to power rapid and synchronous movements of the hind legs. How is this energy stored? Results The hind coxae of the froghopper are linked to the hinges of the ipsilateral hind wings by pleural arches, complex bow-shaped internal skeletal structures. They are built of chitinous cuticle and the rubber-like protein, resilin, which fluoresces bright blue when illuminated with ultra-violet light. The ventral and posterior end of this fluorescent region forms the thoracic part of the pivot with a hind coxa. No other structures in the thorax or hind legs show this blue fluorescence and it is not found in larvae which do not jump. Stimulating one trochanteral depressor muscle in a pattern that simulates its normal action, results in a distortion and forward movement of the posterior part of a pleural arch by 40 &#956;m, but in natural jumping, the movement is at least 100 &#956;m. Conclusion Calculations showed that the resilin itself could only store 1% to 2% of the energy required for jumping. The stiffer cuticular parts of the pleural arches could, however, easily meet all the energy storage needs. The composite structure therefore, combines the stiffness of the chitinous cuticle with the elasticity of resilin. Muscle contractions bend the chitinous cuticle with little deformation and therefore, store the energy needed for jumping, while the resilin rapidly returns its stored energy and thus restores the body to its original shape after a jump and allows repeated jumping
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