Mating opportunities and energetic constraints drive variation in age-dependent sexual signalling

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Online Version of Record published before inclusion in an issue: 11 October 2016When males repeatedly produce energetically expensive sexual signals, trade-offs between current and future investment can cause plasticity in age-dependent signalling. Such variation is often interpreted as alternate adaptive strategies: live fast and die young vs. slow and steady. An alternative (yet rarely tested) explanation is that condition-dependent constraints on allocation cause variation in signalling with age (‘late bloomers’ do not have early investment options). Testing this hypothesis is challenging because resource acquisition and allocation are difficult to measure, and energetic reserves both affect and are affected by reproductive effort. We simultaneously manipulated acquisition (through dietary nutrition) and access to potential mates (as a proxy for manipulating sexual trait allocation) in male decorated crickets (Gryllodes sigillatus), while measuring age- and signalling effort-mediated changes in energy storage components. Increased diet quality caused increased signalling effort and energy storage, while access to females increased both the likelihood of and time spent signalling. Males with lower resource budgets signalled less, but still suffered energetic storage loss and viability costs. Our results suggest that energetic constraints, rather than strategic resource accumulation, reduced signalling levels in males with lower resource acquisition ability. Our findings imply a non-adaptive explanation for age-dependent variation in sexual signalling, and an important role for energetic constraints in maintaining the honesty of costly behavioural displays.T.M.H. and L.F.B. were supported by the University of Stirling. J.H. was funded by a University Royal Society Fellowship. J.R. was funded by a NERC studentship (awarded to J.H)

The meaning and challenge of voluntary counselling and testing (VCT) for counsellors: report of the Kenya Association of Professional Counsellors (KAPC) conference for sub-Saharan Africa

A large number of voluntary counselling and testing (VCT) sites are being opened in sub-Saharan Africa. The services provided by these sites are playing an increasingly important role in the prevention of HIV/AIDS. The sites offer many possibilities and it is crucial that they provide the optimum services for clients. Counselling is an integral part of these services, yet it receives little attention. Counsellors need to be consulted if the optimum services are to be provided, but they are rarely consulted for their professional opinion. Accordingly, the Kenya Association of Professional Counsellors (KAPC) organised a 3-day conference in September 2002 to provide counsellors, drawn from the sub-Saharan region, with a forum to identify VCT-related issues and discuss their implications. The main aim of the conference was for counsellors to arrive at a consensual position regarding HIV/AIDS and what improvements they thought could be made for the VCT services to clients. The counsellors identified the issues that they considered important and this paper presents those issues together with recommendations regarding improvements. Key words:Voluntary counselling and testing (VCT), conference report, sub-Saharan Africa. Les sens et le défi de la consultation et du dépistage volontaires (VCT) auprès des conseillers: le rapport de la conférence sur l'Afrique subsaharienne de l'Association de Conseillers Professionnels du Kenya (KAPC) RÉSUMÉ Un grand nombre de sites de consultation et de dépistage volontaires (VCT) sont mis en place en Afrique subsaharienne. Les services pourvus dans ces sites jouent un rôle encore plus important dans la prévention du VIH/SIDA. Les sites offrent beaucoup de possibilités et il est crucial qu'ils pourvoient des services les meilleurs aux clients. La consultation psychologique fait partie intégrante de ces services, malgré qu'elle reçoit très peu d'attention. Les conseillers psychologiques doivent être consultés si on veut optimiser les services fournis. Malheureusement, ils sont rarement consultés pour leur opinion professionnelle. En conséquence, l'Association des Conseillers Professionnels du Kenya (KAPC) a organisé une conférence sur 3 jours, en septembre 2002, afin de donner aux conseillers, venus de la région subsaharienne, un forum à l'intérieur duquel ils peuvent identifier les problèmes et discuter leurs implications. Le but principal de cette conférence était de permettre les conseillers à se mettre d'accord sur le VIH/SIDA d'une manière unanime et de proposer une amélioration de services de VCT mis à disposition des clients. Les conseillers ont identifié des problèmes considérés primordiaux. Cette communication présente ces problèmes et les recommandations liées aux améliorations proposées. Mots clés : Consultation et dépistage volontaires (VCT), rapport de conférence, Afrique subsaharienne. Sahara J Vol.1(3) 2004: 175-18

Exhaled breath condensate pH as a biomarker of COPD severity in ex-smokers

Endogenous airway acidification, as assessed by exhaled breath condensate (EBC) pH, is present in patients with stable COPD. The aim of this study was to measure EBC pH levels in a large cohort of COPD patients and to evaluate associations with functional parameters according to their smoking status

Janus monolayers of transition metal dichalcogenides.

Structural symmetry-breaking plays a crucial role in determining the electronic band structures of two-dimensional materials. Tremendous efforts have been devoted to breaking the in-plane symmetry of graphene with electric fields on AB-stacked bilayers or stacked van der Waals heterostructures. In contrast, transition metal dichalcogenide monolayers are semiconductors with intrinsic in-plane asymmetry, leading to direct electronic bandgaps, distinctive optical properties and great potential in optoelectronics. Apart from their in-plane inversion asymmetry, an additional degree of freedom allowing spin manipulation can be induced by breaking the out-of-plane mirror symmetry with external electric fields or, as theoretically proposed, with an asymmetric out-of-plane structural configuration. Here, we report a synthetic strategy to grow Janus monolayers of transition metal dichalcogenides breaking the out-of-plane structural symmetry. In particular, based on a MoS2 monolayer, we fully replace the top-layer S with Se atoms. We confirm the Janus structure of MoSSe directly by means of scanning transmission electron microscopy and energy-dependent X-ray photoelectron spectroscopy, and prove the existence of vertical dipoles by second harmonic generation and piezoresponse force microscopy measurements

Services just for men? Insights from a national study of the well men services pilots.

Men continue to have a lower life expectancy in most countries compared to women. Explanations of this gendered health inequality tend to focus on male risk taking, unhealthy lifestyle choices and resistance to seeking help from health services. In the period 2005-2008 the Scottish Government funded a nationwide community health promotion programme aimed at improving men's health, called Well Men Service Pilots (henceforth WMS)

Comparison of exhaled breath condensate pH using two commercially available devices in healthy controls, asthma and COPD patients

<p>Abstract</p> <p>Background</p> <p>Analysis of exhaled breath condensate (EBC) is a non-invasive method for studying the acidity (pH) of airway secretions in patients with inflammatory lung diseases.</p> <p>Aim</p> <p>To assess the reproducibility of EBC pH for two commercially available devices (portable RTube and non-portable ECoScreen) in healthy controls, patients with asthma or COPD, and subjects suffering from an acute cold with lower-airway symptoms. In addition, we assessed the repeatability in healthy controls.</p> <p>Methods</p> <p>EBC was collected from 40 subjects (n = 10 in each of the above groups) using RTube and ECoScreen. EBC was collected from controls on two separate occasions within 5 days. pH in EBC was assessed after degasification with argon for 20 min.</p> <p>Results</p> <p>In controls, pH-measurements in EBC collected by RTube or ECoScreen showed no significant difference between devices (p = 0.754) or between days (repeatability coefficient RTube: 0.47; ECoScreen: 0.42) of collection. A comparison between EBC pH collected by the two devices in asthma, COPD and cold patients also showed good reproducibility. No differences in pH values were observed between controls (mean pH 8.27; RTube) and patients with COPD (pH 7.97) or asthma (pH 8.20), but lower values were found using both devices in patients with a cold (pH 7.56; RTube, p < 0.01; ECoScreen, p < 0.05).</p> <p>Conclusion</p> <p>We conclude that pH measurements in EBC collected by RTube and ECoScreen are repeatable and reproducible in healthy controls, and are reproducible and comparable in healthy controls, COPD and asthma patients, and subjects with a common cold.</p

Obesity and poor breast cancer prognosis: an illusion because of hormone replacement therapy?

High body mass index (BMI) and use of hormone replacement therapy (HRT) increase the risk of postmenopausal breast cancer. It has been shown that BMI modifies the effect of HRT, as its influence is most pronounced in lean women. We investigated the influence of BMI and HRT on prognosis in 2640 postmenopausal women diagnosed with breast cancer in Sweden in 1993–1995, taking into account HRT and mammography before diagnosis. Logistic and Cox regression were used. In non-users of HRT, obese women (BMI >30) compared with normal weight women (BMI <25) had a similar prognosis (hazard ratio (HR) 1.1, 95% confidence interval (CI) 0.8–1.6), despite larger tumours found in obese women. Obese HRT users had less favourable tumour characteristics and poorer prognosis compared with normal weight women (HR 3.7, 95% CI 1.9–7.2). The influence of BMI on breast cancer prognosis was similar whether diagnosed by mammographic screening or not. We found a similar prognosis of postmenopausal breast cancer-specific death regardless of BMI in non-users of HRT, but among HRT users obesity was associated with a poorer breast cancer prognosis

The Endocrine and Metabolic Characteristics of a Large Bardet-Biedl Syndrome Clinic Population

Context: Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder in which previous reports have described obesity and a metabolic syndrome. Objective: We describe the endocrine and metabolic characteristics of a large BBS population compared with matched control subjects. Design: We performed a case-control study. Setting: This study was performed at a hospital clinic. Patients: Study patients had a clinical or genetic diagnosis of BBS. Main Outcome Measurements: Our study determined the prevalence of a metabolic syndrome in our cohort. Results: A total of 152 subjects were studied. Eighty-four (55.3%) were male. Mean (± standard deviation) age was 33.2 ± 1.0 years. Compared with age-, sex-, and body mass index-matched control subjects, fasting glucose and insulin levels were significantly higher in subjects with BBS (glucose: BBS, 5.2 ± 1.2 mmol/L vs control, 4.9 ± 0.9 mmol/L, P = 0.04; insulin: BBS, 24.2 ± 17.0 pmol/L vs control, 14.2 ± 14.8 pmol/L, P < 0.001). Serum triglycerides were significantly higher in subjects with BBS (2.0 ± 1.2 mmol/L) compared with control subjects (1.3 ± 0.8 mmol/L; P < 0.001), but total cholesterol, high-density lipoprotein, and low-density lipoprotein were similar in both groups. Systolic blood pressure was higher in the BBS group (BBS, 135 ± 18 mm Hg vs control subjects, 129 ± 16 mm Hg; P = 0.02). Alanine transaminase was raised in 34 (26.8%) subjects with BBS, compared with five (8.9%) control subjects (P = 0.01). The rate of metabolic syndrome, determined using International Diabetes Federation criteria, was significantly higher in the BBS group (54.3%) compared with control subjects (26% P < 0.001). Twenty-six (19.5%) of male subjects with BBS were hypogonadal (serum testosterone, 9.9 ± 5.3 mmol/L), but significant pituitary abnormalities were uncommon. Subclinical hypothyroidism was present in 24 of 125 (19.4%) patients with BBS, compared with 3 of 65 (4.6%) control subjects (P = 0.01). Conclusions: Insulin resistance and the metabolic syndrome are increased in adult patients with BBS compared with matched control subjects. Increased subclinical hypothyroidism in the BBS cohort needs further investigation

Electron quantum metamaterials in van der Waals heterostructures

In recent decades, scientists have developed the means to engineer synthetic periodic arrays with feature sizes below the wavelength of light. When such features are appropriately structured, electromagnetic radiation can be manipulated in unusual ways, resulting in optical metamaterials whose function is directly controlled through nanoscale structure. Nature, too, has adopted such techniques -- for example in the unique coloring of butterfly wings -- to manipulate photons as they propagate through nanoscale periodic assemblies. In this Perspective, we highlight the intriguing potential of designer sub-electron wavelength (as well as wavelength-scale) structuring of electronic matter, which affords a new range of synthetic quantum metamaterials with unconventional responses. Driven by experimental developments in stacking atomically layered heterostructures -- e.g., mechanical pick-up/transfer assembly -- atomic scale registrations and structures can be readily tuned over distances smaller than characteristic electronic length-scales (such as electron wavelength, screening length, and electron mean free path). Yet electronic metamaterials promise far richer categories of behavior than those found in conventional optical metamaterial technologies. This is because unlike photons that scarcely interact with each other, electrons in subwavelength structured metamaterials are charged, and strongly interact. As a result, an enormous variety of emergent phenomena can be expected, and radically new classes of interacting quantum metamaterials designed