Resting vs. active: a meta-analysis of the intra- and inter-specific associations between minimum, sustained, and maximum metabolic rates in vertebrates

Variation in aerobic capacity has far reaching consequences for the physiology, ecology, and evolution of vertebrates. Whether at rest or active, animals are constrained to operate within the energetic bounds determined by their minimum (minMR) and sustained or maximum metabolic rates (upperMR). MinMR and upperMR can differ considerably among individuals and species but are often presumed to be mechanistically linked to one another. Specifically, minMR is thought to reflect the idling cost of the machinery needed to support upperMR. However, previous analyses based on limited datasets have come to conflicting conclusions regarding the generality and strength of their association. Here we conduct the first comprehensive assessment of their relationship, based on a large number of published estimates of both the intra-specific (n = 176) and inter-specific (n = 41) phenotypic correlations between minMR and upperMR, estimated as either exercise-induced maximum metabolic rate (VO2max), cold-induced summit metabolic rate (Msum), or daily energy expenditure (DEE). Our meta-analysis shows that there is a general positive association between minMR and upperMR that is shared among vertebrate taxonomic classes. However, there was stronger evidence for intra-specific correlations between minMR and Msum and between minMR and DEE than there was for a correlation between minMR and VO2max across different taxa. As expected, inter-specific correlation estimates were consistently higher than intra-specific estimates across all traits and vertebrate classes. An interesting exception to this general trend was observed in mammals, which contrast with birds and exhibit no correlation between minMR and Msum. We speculate that this is due to the evolution and recruitment of brown fat as a thermogenic tissue, which illustrates how some species and lineages might circumvent this seemingly general association. We conclude that, in spite of some variability across taxa and traits, the contention that minMR and upperMR are positively correlated generally holds true both within and across vertebrate species. Ecological and comparative studies should therefore take into consideration the possibility that variation in any one of these traits might partly reflect correlated responses to selection on other metabolic parameters

CMB Telescopes and Optical Systems

The cosmic microwave background radiation (CMB) is now firmly established as a fundamental and essential probe of the geometry, constituents, and birth of the Universe. The CMB is a potent observable because it can be measured with precision and accuracy. Just as importantly, theoretical models of the Universe can predict the characteristics of the CMB to high accuracy, and those predictions can be directly compared to observations. There are multiple aspects associated with making a precise measurement. In this review, we focus on optical components for the instrumentation used to measure the CMB polarization and temperature anisotropy. We begin with an overview of general considerations for CMB observations and discuss common concepts used in the community. We next consider a variety of alternatives available for a designer of a CMB telescope. Our discussion is guided by the ground and balloon-based instruments that have been implemented over the years. In the same vein, we compare the arc-minute resolution Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT). CMB interferometers are presented briefly. We conclude with a comparison of the four CMB satellites, Relikt, COBE, WMAP, and Planck, to demonstrate a remarkable evolution in design, sensitivity, resolution, and complexity over the past thirty years.Comment: To appear in: Planets, Stars and Stellar Systems (PSSS), Volume 1: Telescopes and Instrumentatio

Issues raised developing AQuRate (an authoring tool that uses the question and test interoperability version 2 specification)

The IMS Question & Test Interoperability (QTI) specification has existed for many years, and there are a few tools for authoring questions in early versions of the specification. However, the new QTIv2 specification was unsupported in any existing authoring environment. The AQuRate project was funded by JISC’s capital project program to fill this gap. AQuRate is one of three JISC projects, which together aimed to support the whole e-assessment process, from authoring (AQuRate at Kingston University) to storage (Minibix at Cambridge) and finally to a delivery/assessment development (ASDEL at Southampton). This paper considers issues raised during the creation of the tool: data modelling, graphical user interface design, and use cases. It ends raising issues currently effecting on-going development

Ovarian cancer

Ovarian cancer is not a single disease and can be subdivided into at least five different histological subtypes that have different identifiable risk factors, cells of origin, molecular compositions, clinical features and treatments. Ovarian cancer is a global problem, is typically diagnosed at a late stage and has no effective screening strategy. Standard treatments for newly diagnosed cancer consist of cytoreductive surgery and platinum-based chemotherapy. In recurrent cancer, chemotherapy, anti-angiogenic agents and poly(ADP-ribose) polymerase inhibitors are used, and immunological therapies are currently being tested. High-grade serous carcinoma (HGSC) is the most commonly diagnosed form of ovarian cancer and at diagnosis is typically very responsive to platinum-based chemotherapy. However, in addition to the other histologies, HGSCs frequently relapse and become increasingly resistant to chemotherapy. Consequently, understanding the mechanisms underlying platinum resistance and finding ways to overcome them are active areas of study in ovarian cancer. Substantial progress has been made in identifying genes that are associated with a high risk of ovarian cancer (such as BRCA1 and BRCA2), as well as a precursor lesion of HGSC called serous tubal intraepithelial carcinoma, which holds promise for identifying individuals at high risk of developing the disease and for developing prevention strategies

Development of a portfolio of learning for postgraduate family medicine training in South Africa: a Delphi study

<p>Abstract</p> <p>Background</p> <p>Within the 52 health districts in South Africa, the family physician is seen as the clinical leader within a multi-professional district health team. Family physicians must be competent to meet 90% of the health needs of the communities in their districts. The eight university departments of Family Medicine have identified five unit standards, broken down into 85 training outcomes, for postgraduate training. The family medicine registrar must prove at the end of training that all the required training outcomes have been attained. District health managers must be assured that the family physician is competent to deliver the expected service. The Colleges of Medicine of South Africa (CMSA) require a portfolio to be submitted as part of the uniform assessment of all registrars applying to write the national fellowship examinations. This study aimed to achieve a consensus on the contents and principles of the first national portfolio for use in family medicine training in South Africa.</p> <p>Methods</p> <p>A workshop held at the WONCA Africa Regional Conference in 2009 explored the purpose and broad contents of the portfolio. The 85 training outcomes, ideas from the WONCA workshop, the literature, and existing portfolios in the various universities were used to develop a questionnaire that was tested for content validity by a panel of 31 experts in family medicine in South Africa, via the Delphi technique in four rounds. Eighty five content items (national learning outcomes) and 27 principles were tested. Consensus was defined as 70% agreement. For those items that the panel thought should be included, they were also asked how to provide evidence for the specific item in the portfolio, and how to assess that evidence.</p> <p>Results</p> <p>Consensus was reached on 61 of the 85 national learning outcomes. The panel recommended that 50 be assessed by the portfolio and 11 should not be. No consensus could be reached on the remaining 24 outcomes and these were also omitted from the portfolio. The panel recommended that various types of evidence be included in the portfolio. The panel supported 26 of the 27 principles, but could not reach consensus on whether the portfolio should reflect on the relationship between the supervisor and registrar.</p> <p>Conclusion</p> <p>A portfolio was developed and distributed to the eight departments of Family Medicine in South Africa, and the CMSA, to be further tested in implementation.</p

Engaging Men in Prevention and Care for HIV/AIDS in Africa

Ed Mills and colleagues argue that a more balanced approach to gender is needed so that both men and women are involved in HIV treatment and prevention

WWOX expression in colorectal cancer—a real-time quantitative RT-PCR study

The WWOX gene is a tumour suppressor gene affected in various types of malignancies. Numerous studies showed either loss or reduction of the WWOX expression in variety of tumours, including breast, ovary, liver, stomach and pancreas. Recent study demonstrated that breast cancer patients exhibiting higher WWOX expression showed significantly longer disease-free survival in contrast to the group with lower relative WWOX level. This work was undertaken to show whether similar phenomena take place in colon tumours and cell lines. To assess the correlation of WWOX gene expression with prognosis and cancer recurrence in 99 colorectal cancer patients, we performed qRT-PCR analysis. We also performed analysis of WWOX promoter methylation status using MethylScreen method and analysis of loss of heterozygosity (LOH) status at two WWOX-related loci, previously shown to be frequently deleted in various types of tumours. A significantly better disease-free survival was observed among patients with tumours exhibiting high level of WWOX (hazard ratio = 0.39; p = 0.0452; Mantel–Cox log-rank test), but in multivariate analysis it was not an independent prognostic factor. We also found that although in colorectal cancer WWOX expression varies among patients and correlates with DFS, the exact mode of decrease in this type of tumour was not found. We failed to find the evidence of LOH in WWOX region, or hypermethylation in promoter regions of this gene. Although we provide the evidence for tumour-suppressive role of WWOX gene expression in colon, we were unable to identify the molecular mechanism responsible for this

MRI/PET Brain Imaging

Multimodal brain imaging has become an established clinical and research tool for diagnosis and disease progression of brain disorders. Among available imaging modalities, magnetic resonance imaging (MRI) and positron-emission tomography (PET) can provide a wide spectrum of data for the in vivo mapping of neurobiological functions and brain morphology while demonstrating to relationships between behavioral and neurobiological factors. Since MRI mostly uses endogenous contrast mechanisms to visualize and quantify tissue characteristics, optimal sequence design is essential for the diagnostic information of MRI. On the other hand, PET imaging is always based on the exogenous contrast of an injected PET tracer. Therefore, characteristics of the PET tracer determine the quantitative and diagnostic potential of PET. This chapter will focus on both of these modalities and shortly discuss the potential of multimodal or hybrid MR/PET imaging. We will not cover MR spectroscopy nor specific applications of H215O PET since this will be discussed in other chapters of this book.</p

Vesicular Stomatitis Virus-Based Ebola Vaccine Is Well-Tolerated and Protects Immunocompromised Nonhuman Primates

Ebola virus (EBOV) is a significant human pathogen that presents a public health concern as an emerging/re-emerging virus and as a potential biological weapon. Substantial progress has been made over the last decade in developing candidate preventive vaccines that can protect nonhuman primates against EBOV. Among these prospects, a vaccine based on recombinant vesicular stomatitis virus (VSV) is particularly robust, as it can also confer protection when administered as a postexposure treatment. A concern that has been raised regarding the replication-competent VSV vectors that express EBOV glycoproteins is how these vectors would be tolerated by individuals with altered or compromised immune systems such as patients infected with HIV. This is especially important as all EBOV outbreaks to date have occurred in areas of Central and Western Africa with high HIV incidence rates in the population. In order to address this concern, we evaluated the safety of the recombinant VSV vector expressing the Zaire ebolavirus glycoprotein (VSVΔG/ZEBOVGP) in six rhesus macaques infected with simian-human immunodeficiency virus (SHIV). All six animals showed no evidence of illness associated with the VSVΔG/ZEBOVGP vaccine, suggesting that this vaccine may be safe in immunocompromised populations. While one goal of the study was to evaluate the safety of the candidate vaccine platform, it was also of interest to determine if altered immune status would affect vaccine efficacy. The vaccine protected 4 of 6 SHIV-infected macaques from death following ZEBOV challenge. Evaluation of CD4+ T cells in all animals showed that the animals that succumbed to lethal ZEBOV challenge had the lowest CD4+ counts, suggesting that CD4+ T cells may play a role in mediating protection against ZEBOV