Photovoltaic effect in ferroelectric ceramics

The ceramic structure was simulated in a form that is more tractable to correlation between experiment and theory. Single crystals (of barium titanate) were fabricated in a simple corrugated structure in which the pedestals of the corrugation simulated the grain while the intervening cuts could be filled with materials simulating the grain boundaries. The observed photovoltages were extremely small (100 mv)

Behavioural adaptation and acceptance

One purpose of Intelligent Vehicles is to improve road safety, throughput, and emissions. However, the predicted effects are not always as large as aimed for. Part of this is due to indirect behavioral changes of drivers, also called behavioral adaptation. Behavioral adaptation (BA) refers to unintended behavior that arises following a change to the road traffic system. Qualitative models of behavioral adaptation (formerly known as risk compensation) describe BA by the change in the subjectively perceived enhancement of the safety margins. If a driver thinks that the system is able to enhance safety and also perceives the change in behavior as advantageous, adaptation occurs. The amount of adaptation is (indirectly) influenced by the driver personality and trust in the system. This also means that the amount of adaptation differs between user groups and evenwithin one driver or changes over time. Examples of behavioral change are the generation of extra mobility (e.g., taking the car instead of the train), road use by ‘‘less qualified’’ drivers (e.g., novice drivers), driving under more difficult conditions (e.g., driving on slippery roads), or a change in distance to the vehicle ahead (e.g., driving closer to a lead vehicle with ABS). In effect predictions, behavioral adaptation should be taken into account. Even though it may reduce beneficial effects, BA (normally) does not eliminate the positive effects. How much the effects are reduced depends on the type of ADAS, the design of the ADAS, the driver, the current state of the driver, and the local traffic and weather conditions

The size-Ramsey number of powers of paths

Given graphs $G$ and $H$ and a positive integer $q$, say that $G$ \emph{is $q$-Ramsey for} $H$, denoted $G\rightarrow (H)_q$, if every $q$-colouring of the edges of $G$ contains a monochromatic copy of $H$. The \emph{size-Ramsey number} \sr(H) of a graph $H$ is defined to be \sr(H)=\min\{|E(G)|\colon G\rightarrow (H)_2\}. Answering a question of Conlon, we prove that, for every fixed~$k$, we have \sr(P_n^k)=O(n), where~$P_n^k$ is the $k$th power of the $n$-vertex path $P_n$ (i.e., the graph with vertex set $V(P_n)$ and all edges $\{u,v\}$ such that the distance between $u$ and $v$ in $P_n$ is at most $k$). Our proof is probabilistic, but can also be made constructive.Most of the work for this paper was done during my PhD, which was half funded by EPSRC grant reference 1360036, and half by Merton College Oxford. The third author was partially supported by FAPESP (Proc.~2013/03447-6) and by CNPq (Proc.~459335/2014-6, 310974/2013-5). The fifth author was supported by FAPESP (Proc.~2013/11431-2, Proc.~2013/03447-6 and Proc.~2018/04876-1) and partially by CNPq (Proc.~459335/2014-6). This research was supported in part by CAPES (Finance Code 001). The collaboration of part of the authors was supported by a CAPES/DAAD PROBRAL grant (Proc.~430/15)

Women in senior post-graduate medicine career roles in the UK: a qualitative study

Objectives:This qualitative study sought to elicit the views, experiences, career journeys and aspirations of women in senior post-graduate medical education roles to identify steps needed to help support career progression.Design:In-depth semi-structured telephone interviews.Setting:UKParticipants:Purposive sample of 12 women in a variety of senior leadership roles in post-graduate medical education in the UK.Main outcome measures:Self reported motivating influences, factors that helped and hindered progress, key branch points, and key educational factors and social support impacting on participants' career in postgraduate medicine.Results:Respondents often reported that career journeys were serendipitous, rather than planned, formal or well structured. Senior women leaders reported having a high internal locus of control, with very high levels of commitment to the NHS. All reported significant levels of drive, although the majority indicated that they were not ambitious in the sense of a strong drive for money, prestige, recognition or power. They perceived that there was an under-representation of women in senior leadership positions and that high-quality female mentorship was particularly important in redressing this imbalance. Social support, such a spouse or other significant family member, was particularly valued as reaffirming and supporting women’s chosen career ambition. Factors that were considered to have hindered career progression included low self-confidence and self-efficacy, the so-called glass ceiling and perceived self-limiting cultural influences. Factors indirectly linked to gender such as part-time versus working full time were reportedly influential in being overlooked for senior leadership roles. Implications of these findings are discussed in the paper.Conclusion:Social support, mentorship and role modelling are all perceived as highly important in redressing perceived gender imbalances in careers in post-graduate medical education

Methyl methanesulfonate (MMS) produces heat-labile DNA damage but no detectable in vivo DNA double-strand breaks

Homologous recombination (HR) deficient cells are sensitive to methyl methanesulfonate (MMS). HR is usually involved in the repair of DNA double-strand breaks (DSBs) in Saccharomyces cerevisiae implying that MMS somehow induces DSBs in vivo. Indeed there is evidence, based on pulsed-field gel electrophoresis (PFGE), that MMS causes DNA fragmentation. However, the mechanism through which MMS induces DSBs has not been demonstrated. Here, we show that DNA fragmentation following MMS treatment, and detected by PFGE is not the consequence of production of cellular DSBs. Instead, DSBs seen following MMS treatment are produced during sample preparation where heat-labile methylated DNA is converted into DSBs. Furthermore, we show that the repair of MMS-induced heat-labile damage requires the base excision repair protein XRCC1, and is independent of HR in both S.cerevisiae and mammalian cells. We speculate that the reason for recombination-deficient cells being sensitive to MMS is due to the role of HR in repair of MMS-induced stalled replication forks, rather than for repair of cellular DSBs or heat-labile damage

Beta cell function after weight loss: a clinical trial comparing gastric bypass surgery and intensive lifestyle intervention

The effects of various weight loss strategies on pancreatic beta cell function remain unclear. We aimed to compare the effect of intensive lifestyle intervention (ILI) and Roux-en-Y gastric bypass surgery (RYGB) on beta cell function. Design One year controlled clinical trial (ClinicalTrials.gov identifier NCT00273104). One hundred and nineteen morbidly obese participants without known diabetes from the MOBIL study (mean (s.d.) age 43.6 (10.8) years, body mass index (BMI) 45.5 (5.6) kg/m2, 84 women) were allocated to RYGB (n=64) or ILI (n=55). The patients underwent repeated oral glucose tolerance tests (OGTTs) and were categorised as having either normal (NGT) or abnormal glucose tolerance (AGT). Twenty-nine normal-weight subjects with NGT (age 42.6 (8.7) years, BMI 22.6 (1.5) kg/m2, 19 women) served as controls. OGTT-based indices of beta cell function were calculated. One year weight reduction was 30 % (8) after RYGB and 9 % (10) after ILI (P<0.001). Disposition index (DI) increased in all treatment groups (all P<0.05), although more in the surgery groups (both P<0.001). Stimulated proinsulin-to-insulin (PI/I) ratio decreased in both surgery groups (both P<0.001), but to a greater extent in the surgery group with AGT at baseline (P<0.001). Post surgery, patients with NGT at baseline had higher DI and lower stimulated PI/I ratio than controls (both P<0.027). Gastric bypass surgery improved beta cell function to a significantly greater extent than ILI. Supra-physiological insulin secretion and proinsulin processing may indicate excessive beta cell function after gastric bypass surgery

Small-scale on-site treatment of fecal matter: comparison of treatments for resource recovery and sanitization

On-site small-scale sanitation is common in rural areas and areas without infrastructure, but the treatment of the collected fecal matter can be inefficient and is seldom directed to resource recovery. The aim of this study was to compare low-technology solutions such as composting and lactic acid fermentation (LAF) followed by vermicomposting in terms of treatment efficiency, potential human and environmental risks, and stabilization of the material for reuse in agriculture. A specific and novel focus of the study was the fate of native pharmaceutical compounds in the fecal matter. Composting, with and without the addition of biochar, was monitored by temperature and CO2 production and compared with LAF. All treatments were run at three different ambient temperatures (7, 20, and 38°C) and followed by vermicomposting at room temperature. Materials resulting from composting and LAF were analyzed for fecal indicators, physicochemical characteristics, and residues of ten commonly used pharmaceuticals and compared to the initial substrate. Vermicomposting was used as secondary treatment and assessed by enumeration of Escherichia coli, worm density, and physicochemical characteristics. Composting at 38°C induced the highest microbial activity and resulted in better stability of the treated material, higher N content, lower numbers of fecal indicators, and less pharmaceutical compounds as compared to LAF. Even though analysis of pH after LAF suggested incomplete fermentation, E. coli cell numbers were significantly lower in all LAF treatments compared to composting at 7°C, and some of the anionic pharmaceutical compounds were detected in lower concentrations. The addition of approximately 5 vol % biochar to the composting did not yield significant differences in measured parameters. Vermicomposting further stabilized the material, and the treatments previously composted at 7°C and 20°C had the highest worm density. These results suggest that in small-scale decentralized sanitary facilities, the ambient temperatures can significantly influence the treatment and the options for safe reuse of the material.publishedVersio

A 1400-Year Oxygen Isotope History from the Ross Sea Area, Antarctica

Four ice cores from the Ross Sea drainage, Antarctica, show patterns of δ18O variations on a time scale of decades to centuries over the last 1400 years without change in the long-term average δ18O. Century scale δ18O fluctuations in the two cores drilled in the Ross Ice Shelf at Station J-9 (82° 23\u27 S, 168° 38\u27 W, elevation 60 m) are highly correlated (P \u3c 2 x 10-4). The long isotope record (\u3e30 000 a) of the 1978 1-9 core thus represents local conditions over at least 102 m and on time scales of 100 years and longer. Regional correlations between the 1-9 δ18O records and those from Ridge BC (82 ° 54\u27S, 136 ° 40\u27W, elevation 509 m) and the Dominion Range (85 ° 15\u27 S, 166 ° 10\u27 E, elevation 2700 m) are barely significant (P ≈ 0.05 for J-9 \u2776 and Dominion Range, δ18O to 1400 years ago) or absent. The failure to find clear regional isotope trends related to climate fluctuations may reflect the finding that between 1957 and 1982 the area was in the transition zone between areas with opposite temperature trends, and showed little or no temperature change. The fact that the records nevertheless show significant δ18O fluctuations highlights the need to base regional climate reconstructions on a regional suite of ice-core records

The association of early post-transplant glucose levels with long-term mortality

Aims/objective: We aimed to assess the long-term effects of post-transplant glycaemia on long-term survival after renal transplantation. Methods: Study participants were 1,410 consecutive transplant recipients without known diabetes who underwent an OGTT 10 weeks post-transplant and were observed for a median of 6.7 years (range 0.3–13.8 years). The HRs adjusted for age, sex, traditional risk factors and transplant-related risk factors were estimated. Results: Each 1 mmol/l increase in fasting plasma glucose (fPG) or 2 h plasma glucose (2hPG) was associated with 11% (95% CI −1%, 24%) and 5% (1%, 9%) increments in all-cause mortality risk and 19% (1%, 39%) and 6% (1%, 12%) increments in cardiovascular (CV) mortality risk, respectively. Including both fPG and 2hPG in the multi-adjusted model the HR for 2hPG remained unchanged, while the HR for fPG was attenuated (1.05 [1.00, 1.11] and 0.97 [0.84, 1.14]). Compared with recipients with normal glucose tolerance, patients with post-transplant diabetes mellitus had higher all-cause and CV mortality (1.54 [1.09, 2.17] and 1.80 [1.10, 2.96]), while patients with impaired glucose tolerance (IGT) had higher all-cause, but not CV mortality (1.39 [1.01, 1.91] and 1.04 [0.62, 1.74]). Conversely, impaired fasting glucose was not associated with increased all-cause or CV mortality (0.79 [0.52, 1.23] and 0.76 [0.39, 1.49]). Post-challenge hyperglycaemia predicted death from any cause and infectious disease in the multivariable analyses (1.49 [1.15, 1.95] and 1.91 [1.09, 3.33]). Conclusions/interpretation: For predicting all-cause and CV mortality, 2hPG is superior to fPG after renal transplantation. Also, early post-transplant diabetes, IGT and post-challenge hyperglycaemia were significant predictors of death. Future studies should determine whether an OGTT helps identify renal transplant recipients at increased risk of premature death. © The Author(s) 2011. This article is published with open access at Springerlink.co