Comment on "Local accumulation times for source, diffusion, and degradation models in two and three dimensions" [J. Chem. Phys. 138, 104121 (2013)]

In a recent paper, Gordon, Muratov, and Shvartsman studied a partial differential equation (PDE) model describing radially symmetric diffusion and degradation in two and three dimensions. They paid particular attention to the local accumulation time (LAT), also known in the literature as the mean action time, which is a spatially dependent timescale that can be used to provide an estimate of the time required for the transient solution to effectively reach steady state. They presented exact results for three-dimensional applications and gave approximate results for the two-dimensional analogue. Here we make two generalizations of Gordon, Muratov, and Shvartsman’s work: (i) we present an exact expression for the LAT in any dimension and (ii) we present an exact expression for the variance of the distribution. The variance provides useful information regarding the spread about the mean that is not captured by the LAT. We conclude by describing further extensions of the model that were not considered by Gordon,Muratov, and Shvartsman. We have found that exact expressions for the LAT can also be derived for these important extensions..

Tetrahydrobiopterin Supplementation Improves Endothelial Function But Does Not Alter Aortic Stiffness in Patients With Rheumatoid Arthritis.

BACKGROUND: Rheumatoid arthritis is a systemic inflammatory condition associated with increased cardiovascular risk that may be due to underlying endothelial dysfunction and subsequent aortic stiffening. We hypothesized that supplementation with tetrahydrobiopterin (BH4) would recouple endothelial nitric oxide synthase and thus improve endothelial function and consequently reduce aortic stiffness. METHODS AND RESULTS: We conducted 2 randomized, double-blinded, placebo-controlled crossover studies examining 2 separate regimens: an acute regimen, with a single dose of BH4 400 mg versus placebo (n=18), and a short-term regimen, composed of a 1-week treatment with BH4 400 mg once daily versus placebo (n=15). Flow-mediated dilatation and aortic pulse wave velocity were studied 4 times, before and after each treatment phase. Acute BH4 supplementation led to an improvement of flow-mediated dilatation, whereas placebo had no effect (mean±SD of effect difference 2.56±4.79%; P=0.03). Similarly, 1-week treatment with BH4 improved endothelial function, but there was no change with placebo (mean±SD of effect difference 3.50±5.05%; P=0.02). There was no change in aortic pulse wave velocity following acute or short-term BH4 supplementation or placebo (mean±SD of effect difference: acute 0.09±0.67 m/s, P=0.6; short-term 0.03±1.46 m/s, P=0.9). CONCLUSION: Both acute and short-term supplementation with oral BH4 improved endothelial function but not aortic stiffness. This result suggests that BH4 supplementation may be beneficial for patients with rheumatoid arthritis by improving endothelial dysfunction and potentially reducing risk of cardiovascular disease. There appears to be no causal relationship between endothelial function and aortic stiffness, suggesting that they occur in parallel, although they may share common risk factors such as inflammation.KMMP and IBW were funded by British Heart Foundation. IBW, JC and NS received funding from the Comprehensive Local Research Network and IBW and JC from the National Institute for Health Research: Cambridge Biomedical Research Centre.This is the final version of the article. It first appeared from Wiley Blackwell via http://dx.doi.org/10.1161/JAHA.115.00276

General energy bounds for systems of bosons with soft cores

We study a bound system of N identical bosons interacting by model pair potentials of the form V(r) = A sgn(p)r^p + B/r^2, A > 0, B >= 0. By using a variational trial function and the `equivalent 2-body method', we find explicit upper and lower bound formulas for the N-particle ground-state energy in arbitrary spatial dimensions d > 2 for the two cases p = 2 and p = -1. It is demonstrated that the upper bound can be systematically improved with the aid of a special large-N limit in collective field theory

Ensuring young voices are heard in core outcome set development: international workshops with 70 children and young people.

Plain english summaryResearchers test treatments to ensure these work and are safe. They do this by studying the effects that treatments have on patients by measuring outcomes, such as pain and quality of life. Often research teams measure different outcomes even though each team is studying the same condition. This makes it hard to compare the findings from different studies and it can reduce the accuracy of the treatment advice available to patients. Increasingly, researchers are tackling this problem by developing 'core outcome sets'. These are lists of outcomes that all researchers working on a given condition should measure in their studies. It is important that patients have a voice in the development of core outcome sets and children and young people are no exception. But their voices have rarely been heard when core outcome sets are developed. Researchers are trying to address this problem and make sure that core outcome sets are developed in ways that are suitable for children and young people. As a first step, we held two international workshops with children and young people to listen to their views. They emphasised the importance of motivating young people to participate in developing core outcome sets, making them feel valued, and making the development process more interactive, enjoyable and convenient. We hope this commentary will encourage researchers to include children and young people when developing core outcome sets and to adapt their methods so these are suitable for young participants. Future research is important to examine whether these adaptations are effective.AbstractBackground Different research teams looking at treatments for the same condition often select and measure inconsistent treatment outcomes. This makes it difficult to synthesise the results of different studies, leads to selective outcome reporting and impairs the quality of evidence about treatments. 'Core outcome sets' (COS) can help to address these problems. A COS is an agreed, minimum list of outcomes that researchers are encouraged to consistently measure and report in their studies. Including children and young people (CYP) as participants in the development of COS for paediatric conditions ensures that clinically meaningful outcomes are measured and reported. However, few published COS have included CYP as participants. COS developers have described difficulties in recruiting and retaining CYP and there is a lack of guidance on optimising COS methods for them. We aimed to explore CYP's views on the methods used to develop COS and identify ways to optimise these methods.Main body This commentary summarises discussions during two workshops with approximately 70 CYP (aged 10-18 years old) at the International Children's Advisory Network Research and Advocacy Summit, 2018. Delegates described what might motivate them to participate in a COS study, including feeling valued, understanding the need for COS and the importance of input from CYP in their development, and financial and other incentives (e.g. certificates of participation). For Delphi surveys, delegates suggested that lists of outcomes should be as brief as possible, and that scoring and feedback methods should be simplified. For consensus meetings, delegates advised preparing CYP in advance, supporting them during meetings (e.g. via mentors) and favoured arrangements whereby CYP could meet separately from parents and other stakeholders. Overall, they wanted COS methods that were convenient, enjoyable and engaging.Conclusion This commentary points to the limitations of the methods currently used to develop COS with CYP. It also points to ways to motivate CYP to participate in COS studies and to enhancements of methods to make participation more engaging for CYP. Pending much needed research on COS methods for CYP, the perspectives offered in the workshops should help teams developing COS in paediatrics and child health

Building identity in online environments: an Information Science perspective

The research presented in this poster is concerned with the ways in which people use information to build identities for themselves online with reference to the themes of personal reputation management. To date these two themes have been under-explored together in the research literature, both in general, and from an Information Science perspective. The poster content shares findings related to three areas of identity building: (1) the creation and use of online personas and identities; (2) the use of anonymity and pseudonyms through information sharing – or concealment – practices; and (3) the ways in which the blurring or merging together of participants’ private and professional selves. This study used participant diaries and in-depth, semi-structured interviews with 45 UK-based participants. The main finding presented here is that individuals present elements of their online persona or personality using online information, but that they do not do so with the intention of building identity. The findings explored in this presentation are contextualised with reference to identity building in the more formal setting of academic reputation management, i.e. through the use of citation

Author Correction: Possible role of L-form switching in recurrent urinary tract infection.

An amendment to this paper has been published and can be accessed via a link at the top of the paper

Unlocking the role of a genital herpesvirus, otarine herpesvirus 1, in California sea lion cervical cancer

This research was funded by the Geoffrey Hughes Research Fellowship and The Marine Mammal Center.Urogenital carcinoma in California sea lions (Zalophus californianus) is the most common cancer of marine mammals. Primary tumors occur in the cervix, vagina, penis, or prepuce and aggressively metastasize resulting in death. This cancer has been strongly associated with a sexually transmitted herpesvirus, otarine herpesvirus 1 (OtHV1), but the virus has been detected in genital tracts of sea lions without cancer and a causative link has not been established. To determine if OtHV1 has a role in causing urogenital carcinoma we sequenced the viral genome, quantified viral load from cervical tissue from sea lions with (n = 95) and without (n = 163) urogenital carcinoma, and measured viral mRNA expression using in situ mRNA hybridization (Basescope®) to quantify and identify the location of OtHV1 mRNA expression. Of the 95 sea lions diagnosed with urogenital carcinoma, 100% were qPCR positive for OtHV1, and 36% of the sea lions with a normal cervix were positive for the virus. The non-cancer OtHV1 positive cases had significantly lower viral loads in their cervix compared to the cervices from sea lions with urogenital carcinoma. The OtHV1 genome had several genes similar to the known oncogenes, and RNA in situ hybridization demonstrated high OtHV1 mRNA expression within the carcinoma lesions but not in normal cervical epithelium. The high viral loads, high mRNA expression of OtHV1 in the cervical tumors, and the presence of suspected OtHV1 oncogenes support the hypothesis that OtHV1 plays a significant role in the development of sea lion urogenital carcinoma.Publisher PDFPeer reviewe