Testing the planetary models of HU Aquarii

We present new eclipse observations of the polar (i.e. semidetached magnetic white dwarf + M-dwarf binary) HU Aqr, and mid-egress times for each eclipse, which continue to be observed increasingly early. Recent eclipses occurred more than 70 s earlier than the prediction from the latest model that invoked a single circumbinary planet to explain the observed orbital period variations, thereby conclusively proving this model to be incorrect. Using ULTRACAM data, we show that mid-egress times determined for simultaneous data taken at different wavelengths agree with each other. The large variations in the observed eclipse times cannot be explained by planetary models containing up to three planets, because of poor fits to the data as well as orbital instability on short time-scales. The peak-to-peak amplitude of the O−C diagram of almost 140 s is also too great to be caused by Applegate's mechanism, movement of the accretion spot on the surface of the white dwarf, or by asynchronous rotation of the white dwarf. What does cause the observed eclipse time variations remains a mystery

Marine microalgae as a potential source of single cell protein (SCP)

[Abstract] The marine microalgae Tetraselmis suecica, Isochrysis galbana, Dunaliella tertiolecta and Chlorella stigmatophora are good biological sources of single cell protein (SCP). Protein content accounts for 39.12%–54.20% of the dry matter, D. tertiolecta having the highest. Lysine values are between 3.67 and 4.52 g/100 g of protein, and thus are higher than those for freshwater species. The total nucleic acid content is less than 7% of the dry matter; this value is definitely lower than that for yeasts or bacteria, commonly used as SCP sources. Amino acid profiles of the four species are very similar and comparable to the FAO reference protein, buth with a low content of methionine and cystine and a high content of lysine. The MEAA indices are between 81 and 84.98, without significant differences among the four species. Marine microalgae can be used as a potential SCP source

Testing the white dwarf mass-radius relationship with eclipsing binaries

We present high-precision, model-independent, mass and radius measurements for 16 white dwarfs in detached eclipsing binaries and combine these with previously published data to test the theoretical white dwarf mass–radius relationship. We reach a mean precision of 2.4 per cent in mass and 2.7 per cent in radius, with our best measurements reaching a precision of 0.3 per cent in mass and 0.5 per cent in radius. We find excellent agreement between the measured and predicted radii across a wide range of masses and temperatures. We also find the radii of all white dwarfs with masses less than 0.48 M⊙ to be fully consistent with helium core models, but they are on average 9 per cent larger than those of carbon–oxygen core models. In contrast, white dwarfs with masses larger than 0.52 M⊙ all have radii consistent with carbon–oxygen core models. Moreover, we find that all but one of the white dwarfs in our sample have radii consistent with possessing thick surface hydrogen envelopes (10−5 ≥ MH/MWD ≥ 10−4), implying that the surface hydrogen layers of these white dwarfs are not obviously affected by common envelope evolution

Anti-tumour activity in vitro and in vivo of selective differentiating agents containing hydroxamate

A series of hydroxamates, which are not metalloprotease inhibitors, have been found to be selectively toxic to a range of transformed and human tumour cells without killing normal cells (fibroblasts, melanocytes) at the same concentrations. Within 24 h of treatment, drug action is characterized by morphological reversion of tumour cells to a more normal phenotype (dendritic morphology), and rapid and reversible acetylation of histone H4 in both tumour and normal cells. Two; hydroxamates inhibited growth of xenografts of human melanoma cells in nude mice; resistance did not develop in vivo or in vitro. A third hydroxamate, trichostatin A, was active in vitro but became inactivated and had no anti-tumour activity in vivo. Development of dendritic morphology was found to be dependent upon phosphatase activity, RNA and protein synthesis. Proliferating hybrid clones of sensitive and resistant cells remained sensitive to ABHA, indicating a dominant-negative mechanism of sensitivity. Histone H4 hyperacetylation suggests that these agents act at the chromatin level. This work may lead to new drugs that are potent, and selective anti-tumour agents with low toxicity to normal Cells

Laparoscopic treatment of isolated superficial peritoneal endometriosis for managing chronic pelvic pain in women:study protocol for a randomised controlled feasibility trial (ESPriT1)

Background: Endometriosis (where endometrial-like tissue is found outside the uterus) affects ~ 176 million women worldwide and can lead to debilitating pelvic pain. Three subtypes of endometriosis exist, with ~ 80% of women having superficial peritoneal endometriosis (SPE). Endometriosis is diagnosed by laparoscopy and, if SPE is found, gynaecologists usually remove it surgically. However, many women get limited pain relief from surgical removal of SPE. We plan to undertake a future large trial where women who have only SPE found at initial laparoscopy are randomly allocated to have surgical removal (excision or ablation) of SPE, or not. Ultimately, we want to determine whether surgical removal improves overall symptoms and quality of life, or whether surgery is of no benefit, exacerbates symptoms, or even causes harm. The primary objective of this feasibility study is to determine what proportion of women with suspected SPE undergoing diagnostic laparoscopy will agree to randomisation. The secondary objectives are to determine if there are differences in key prognostic parameters between eligible women that agree to be randomised and those that decline; how many women having laparoscopy for investigation of chronic pelvic pain are eligible for the trial; the range of treatment effects and variability in outcomes and the most acceptable methods of recruitment, randomisation and assessment tools. Methods: We will recruit up to 90 women with suspected SPE undergoing diagnostic laparoscopy over a 9-month recruitment period in four Scottish hospitals and randomise them 1:1 to either diagnostic laparoscopy alone (with a sham port to achieve blinding of the allocation) or surgical removal of endometriosis. Baseline characteristics, e.g. age, index of social deprivation, ethnicity, and intensity/duration of pain will be collected. Participants will be followed up by online questionnaires assessing pain, physical and emotional function at baseline, 3 months, 6 months and 12 months. Discussion: Recruitment to a randomised controlled trial to assess the effectiveness of surgery for endometriosis may be challenging because of preconceived ideas about treatment success amongst patients and clinicians. We have designed this study to assess feasibility of recruitment and to inform the design of our future definitive trial. Trial registration: ClincicalTrials.gov, NCT04081532 Status: Recruiting

The ‘Hothaps’ programme for assessing climate change impacts on occupational health and productivity: an invitation to carry out field studies

The ‘high occupational temperature health and productivity suppression’ programme (Hothaps) is a multi-centre health research and prevention programme aimed at quantifying the extent to which working people are affected by, or adapt to, heat exposure while working, and how global heating during climate change may increase such effects. The programme will produce essential new evidence for local, national and global assessment of negative impacts of climate change that have largely been overlooked. It will also identify and evaluate preventive interventions in different social and economic settings

A methodology for parameter estimation in seaweed productivity modelling

This paper presents a combined approach for parameter estimation in models of primary production. The focus is on gross primary production and nutrient assimilation by seaweeds. A database of productivity determinations, biomass and mortality measurements and nutrient uptake rates obtained over one year for Gelidium sesquipedale in the Atlantic Ocean off Portugal has been used. Annual productivity was estimated by harvesting methods, and empirical relationships using mortality/ wave energy and respiration rates have been derived to correct for losses and to convert the estimates to gross production. In situ determinations of productivity have been combined with data on the light climate (radiation periods, intensity, mean turbidity) to give daily and annual productivity estimates. The theoretical nutrient uptake calculated using a 'Redfield ratio' approach and determinations of in situ N and P consumption by the algae during incubation periods have also been compared. The results of the biomass difference and incubation approaches are discussed in order to assess the utility of coefficients determined in situ for parameter estimation in seaweed production models

High-speed photometry of Gaia14aae: an eclipsing AMCVn that challenges formation models

AM CVn-type systems are ultracompact, hydrogen-deficient accreting binaries with degenerate or semidegenerate donors. The evolutionary history of these systems can be explored by constraining the properties of their donor stars. We present high-speed photometry of Gaia14aae, an AM CVn with a binary period of 49. 7 min and the first AM CVn in which the central white dwarf is fully eclipsed by the donor star. Modelling of the light curves of this system allows for the most precise measurement to date of the donor mass of an AM CVn, and relies only on geometric and well-tested physical assumptions. We find a mass ratio q = M2/M1 = 0.0287 ± 0.0020 and masses M1 = 0.87 ± 0.02 M⊙ and M2 = 0.0250 ± 0.0013 M⊙. We compare these properties to the three proposed channels for AM CVn formation. Our measured donor mass and radius do not fit with the contraction that is predicted for AM CVn donors descended from white dwarfs or helium stars at long orbital periods. The donor properties we measure fall in a region of parameter space in which systems evolved from hydrogen-dominated cataclysmic variables are expected, but such systems should show spectroscopic hydrogen, which is not seen in Gaia14aae. The evolutionary history of this system is therefore not clear. We consider a helium-burning star or an evolved cataclysmic variable to be the most likely progenitors, but both models require additional processes and/or fine-tuning to fit the data. Additionally, we calculate an updated ephemeris which corrects for an anomalous time measurement in the previously published ephemeris

How do women at increased, but unexplained, familial risk of breast cancer perceive and manage their risk? A qualitative interview study

<p>Abstract</p> <p>Background</p> <p>The perception of breast cancer risk held by women who have not had breast cancer, and who are at increased, but unexplained, familial risk of breast cancer is poorly described. This study aims to describe risk perception and how it is related to screening behaviour for these women.</p> <p>Methods</p> <p>Participants were recruited from a population-based sample (the Australian Breast Cancer Family Study - ABCFS). The ABCFS includes women diagnosed with breast cancer and their relatives. For this study, women without breast cancer with at least one first- or second-degree relative diagnosed with breast cancer before age 50 were eligible unless a <it>BRCA1 </it>or <it>BRCA2 </it>mutation had been identified in their family. Data collection consisted of an audio recorded, semi-structured interview on the topic of breast cancer risk and screening decision-making. Data was analysed thematically.</p> <p>Results</p> <p>A total of 24 interviews were conducted, and saturation of the main themes was achieved. Women were classified into one of five groups: don't worry about cancer risk, but do screening; concerned about cancer risk, so do something; concerned about cancer risk, so why don't I do anything?; cancer inevitable; cancer unlikely.</p> <p>Conclusions</p> <p>The language and framework women use to describe their risk of breast cancer must be the starting point in attempts to enhance women's understanding of risk and their prevention behaviour.</p

A mammalian functional-genetic approach to characterizing cancer therapeutics

Supplementary information is available online at http://www.nature.com/naturechemicalbiology/. Reprints and permissions information is available online at http://npg.nature.com/reprintsandpermissions/.Identifying mechanisms of drug action remains a fundamental impediment to the development and effective use of chemotherapeutics. Here we describe an RNA interference (RNAi)–based strategy to characterize small-molecule function in mammalian cells. By examining the response of cells expressing short hairpin RNAs (shRNAs) to a diverse selection of chemotherapeutics, we could generate a functional shRNA signature that was able to accurately group drugs into established biochemical modes of action. This, in turn, provided a diversely sampled reference set for high-resolution prediction of mechanisms of action for poorly characterized small molecules. We could further reduce the predictive shRNA target set to as few as eight genes and, by using a newly derived probability-based nearest-neighbors approach, could extend the predictive power of this shRNA set to characterize additional drug categories. Thus, a focused shRNA phenotypic signature can provide a highly sensitive and tractable approach for characterizing new anticancer drugs.National Institute of Mental Health (U.S.) (grant RO1 CA128803-03)American Association for Cancer ResearchMassachusetts Institute of Technology. Dept. of BiologyNational Cancer Institute (U.S.). Integrative Cancer Biology Program (grant 1-U54-CA112967