Note: A miniature oscillating microbalance for sampling ice and volcanic ash from a small airborne platform.

A lightweight and low power oscillating microbalance for in situ sampling of atmospheric ice and volcanic ash is described for airborne platforms. Using a freely exposed collecting wire fixed at only one end to a piezo transducer, the instrument collects airborne materials. Accumulated mass is determined from the change in natural frequency of the wire. The piezo transducer is used in a dual mode to both drive and detect the oscillation. Three independent frequency measurement techniques are implemented with an on-board microcontroller: a frequency sweep, a Fourier spectral method, and a phase-locked loop. These showed agreement to ±0.3 Hz for a 0.5 mm diameter collecting wire of 120 mm long, flown to 19 km altitude on a weather balloon. The instrument is well suited to disposable use with meteorological radiosondes, to provide high resolution vertical profiles of mass concentration.

Coordinated weather balloon solar radiation measurements during a solar eclipse.

Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse radiation measurements. For the 20 March 2015 solar eclipse, a coordinated campaign of balloon-carried solar radiation measurements was undertaken from Reading (51.44°N, 0.94°W), Lerwick (60.15°N, 1.13°W) and Reykjavik (64.13°N, 21.90°W), straddling the path of the eclipse. The balloons reached sufficient altitude at the eclipse time for eclipse-induced variations in solar radiation and solar limb darkening to be measured above cloud. Because the sensor platforms were free to swing, techniques have been evaluated to correct the measurements for their changing orientation. In the swing-averaged technique, the mean value across a set of swings was used to approximate the radiation falling on a horizontal surface; in the swing-maximum technique, the direct beam was estimated by assuming that the maximum solar radiation during a swing occurs when the photodiode sensing surface becomes normal to the direction of the solar beam. Both approaches, essentially independent, give values that agree with theoretical expectations for the eclipse-induced radiation changes.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'.

On the detection and attribution of gravity waves generated by the 20 March 2015 solar eclipse.

Internal gravity waves are generated as adjustment radiation whenever a sudden change in forcing causes the atmosphere to depart from its large-scale balanced state. Such a forcing anomaly occurs during a solar eclipse, when the Moon's shadow cools part of the Earth's surface. The resulting atmospheric gravity waves are associated with pressure and temperature perturbations, which in principle are detectable both at the surface and aloft. In this study, surface pressure and temperature data from two UK sites at Reading and Lerwick are examined for eclipse-driven gravity wave perturbations during the 20 March 2015 solar eclipse over northwest Europe. Radiosonde wind data from the same two sites are also analysed using a moving parcel analysis method, to determine the periodicities of the waves aloft. On this occasion, the perturbations both at the surface and aloft are found not to be confidently attributable to eclipse-driven gravity waves. We conclude that the complex synoptic weather conditions over the UK at the time of this particular eclipse helped to mask any eclipse-driven gravity waves.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'.

Does diabetic status in the ICU predict haemofiltration requirement? The haemofiltration in the ICU and diabetic status (HIDS) study.

Diabetes is already a major health burden and prevalence is expected to double by 2025. The impact of diabetes and clinical outcomes in the intensive care unit is an evolving area of research. This study seeks to identify whether diabetic status is an independent risk factor for haemofiltration. This is a retrospective cohort study. All unique patients from a seven-year period from 2004 to 2010 at a major intensive care unit in Melbourne, Australia were analysed using multivariate regression to look for an association between diabetic status and haemofiltration. After exclusion criteria there were 7262 patients, 1674 with a history of diabetes (median age of 69, 66.72% male) and 5588 without a history of diabetes (median age 64, 64.13% male). Diabetic status was an independent risk factor (odds ratio 1.401, 95% confidence interval 1.079 to 1.820, P=0.011) for haemofiltration. Further research may identify intensive care unit-based renoprotective measures specifically for patients with diabetes.

Evidence of trade-offs shaping virulence evolution in an emerging wildlife pathogen.

In the mid-1990s, the common poultry pathogen Mycoplasma gallisepticum (MG) made a successful species jump to the eastern North American house finch Haemorhous mexicanus (HM). Subsequent strain diversification allows us to directly quantify, in an experimental setting, the transmission dynamics of three sequentially emergent geographic isolates of MG, which differ in the levels of pathogen load they induce. We find significant among-strain variation in rates of transmission as well as recovery. Pathogen strains also differ in their induction of host morbidity, measured as the severity of eye lesions due to infection. Relationships between pathogen traits are also investigated, with transmission and recovery rates being significantly negatively correlated, whereas transmission and virulence, measured as average eye lesion score over the course of infection, are positively correlated. By quantifying these disease-relevant parameters and their relationships, we provide the first analysis of the trade-offs that shape the evolution of this important emerging pathogen.

Coronary angiography and percutaneous coronary intervention in the porcine model: a practical guide to the procedure.

Assessment of safety and efficacy within the porcine coronary artery model remains a standard requirement for new therapies delivered to the coronary arteries before proceeding to clinical testing. Human coronary procedures carry a very low mortality rate; however, procedural mortality for porcine experiments is often high, despite these animals being young and free of atherosclerosis. Some of these deaths are due to poor technique, and therefore avoidable. However, despite the wide use of this model, a systematic description of the procedure has never been published. This article will detail how porcine angiography and stent implantation is performed in our institution and will discuss the relevant differences between humans and pigs with regard to anaesthesia, pharmacotherapy, vascular access, catheter selection and angiographic views. Important variations to the technique that have been reported are also covered.

Genomancy: predicting tumour response to cancer therapy based on the oracle of genetics.

Cells are complex systems that regulate a multitude of biologic pathways involving a diverse array of molecules. Cancer can develop when these pathways become deregulated as a result of mutations in the genes coding for these proteins or of epigenetic changes that affect gene expression, or both1,2. The diversity and interconnectedness of these pathways and their molecular components implies that a variety of mutations may lead to tumorigenic cellular deregulation3-6. This variety, combined with the requirement to overcome multiple anticancer defence mechanisms7, contributes to the heterogeneous nature of cancer. Consequently, tumours with similar histology may vary in their underlying molecular circuitry8-10, with resultant differences in biologic behaviour, manifested in proliferation rate, invasiveness, metastatic potential, and unfortunately, response to cytotoxic therapy. Thus, cancer can be thought of as a family of related tumour subtypes, highlighting the need for individualized prediction both of disease progression and of treatment response, based on the molecular characteristics of the tumour.

Introduction. Stochastic physics and climate modelling.

Finite computing resources limit the spatial resolution of state-of-the-art global climate simulations to hundreds of kilometres. In neither the atmosphere nor the ocean are small-scale processes such as convection, clouds and ocean eddies properly represented. Climate simulations are known to depend, sometimes quite strongly, on the resulting bulk-formula representation of unresolved processes. Stochastic physics schemes within weather and climate models have the potential to represent the dynamical effects of unresolved scales in ways which conventional bulk-formula representations are incapable of so doing. The application of stochastic physics to climate modelling is a rapidly advancing, important and innovative topic. The latest research findings are gathered together in the Theme Issue for which this paper serves as the introduction.

Interactions between sources of mortality and the evolution of parasite virulence.

A well-known result from the theory of the evolution of virulence is the prediction that the virulence of a pathogen (i.e. the rate of parasite-induced host mortality) always evolves to higher levels when host background mortality rates increase. This prediction, however, is derived from models that assume that host mortality sources combine additively to determine the overall host mortality rate. In this paper, we suggest that such additivity is probably rare for many host-pathogen systems, and explore how the predictions for the evolution of virulence are altered when interactions between host mortality sources are incorporated into the theory. Our results indicate that if mortality-source interactions are sufficiently strong then the evolutionarily stable level of virulence can actually decrease as the background mortality rate increases. Consequently, a detailed mechanistic description of how parasites and other mortality sources combine to cause host mortality is required before reliable predictions about virulence evolution can be made. Moreover, mortality-source interactions make empirical comparisons of the virulence of different parasites a much more subtle issue.

The binding of soybean agglutinin (SBA) to the intestinal epithelium of Atlantic salmon, Salmo salar and rainbow trout, Oncorhynchus mykiss, fed high levels of soybean meal.

A lectin present in soya, soybean agglutinin (SBA), was identified in electrophoretic profiles and immunoblots of dehulled solvent-extracted soybean meal (DSSM), full-fat soybean meal (FFSM) and of aqueous extracts of feeds incorporating them in their formulation. A quantitative estimation was made of the proportion of SBA comprising the total protein in FFSM and a trial diet was prepared containing an amount of pure SBA similar to that in diets incorporating high levels of the whole soya product. Fish fed with this diet exhibited similar pathological disruption of the intestinal tract to that observed in fish given a diet with a high level of DSSM (60% of the diet). Furthermore, immuno-histochemistry revealed the binding of the SBA to the enterocytes lining the intestinal villi both of fish fed a diet incorporating pure SBA and those fed a diet containing a high-level of soya (60%). Our results suggest that SBA binds in vivo to the intestinal epithelium of fish and has a contributory role in pathological changes associated with fish feeds containing high levels of soybean proteins.

Evolution of functionality in lattice proteins.

We study the evolution of protein functionality using a two-dimensional lattice model. The characteristics particular to evolution, such as population dynamics and early evolutionary trajectories, have a large effect on the distribution of observed structures. Only subtle differences are observed between the distribution of structures evolved for function and those evolved for their ability to form compact structures.

Treatment type and symptom severity among oncology patients by self-report.

Oncology patients receiving chemotherapy (n=109) and radiation therapy RT (n=161) reported symptom concerns and severity on the 25-item therapy-related symptom checklist (TRSC). Secondary analysis of the self-reports of the two treatment groups was done using the Mann-Whitney U Test. Thirteen symptoms differed significantly between the two groups. RT patients reported significantly greater severity of five symptoms (p<0.05) during therapy. Chemotherapy patients reported significantly greater severity of eight different symptoms. The other 14 items showed a heterogeneous pattern of self-reported patient symptom concerns. The TRSC appears to be a clinically useful self-report checklist that captures the more important symptom concerns of both RT and chemotherapy patients. Earlier efforts to develop this checklist are reviewed briefly.

Balinese mothers' developmental timetables for young children.

The study examined Balinese mothers' expectations for children's development and mothers' child-rearing practices, as influenced by selected variables (child's gender and ordinal position, mother's education, and rural or urban residence). Rural (n = 100) and urban (n = 100) mothers responded to structured questionnaires read aloud to them by trained interviewers who recorded responses. All children were between 4 and 6 years. Equal numbers of male and female children were included, and the entire economic and educational ranges of families were represented. MANOVA results showed significant interaction effects of residential location and maternal education on mothers' expectations of children's cognitive, F(2, 170) = 4.31, p = .04, and psychosocial development, F(2, 170) = 4.35, p = .01. Significant interaction effects were found for maternal education, residential location, child's ordinal position, and gender, F(3, 170) = 5.92, p = .001, on maternal child-rearing practices. Two developmental timetables were constructed.

Bicyclic pyridones as potent, efficacious and orally bioavailable thrombin inhibitors.

A new class of conformationally constrained thrombin inhibitors is described. These compounds contain a unique bicyclic pyridone scaffold which serves as a P3P2 dipeptide surrogate. The synthesis and antithrombotic activity of these inhibitors is reported.

Mothers' developmental expectations for young children in the Philippines.

The purpose of the study was to investigate the developmental timetables of rural and urban mothers in the Central Visayas, Philippines. Examined were mothers' expectations for children's development (physical/perceptual-motor, cognitive, and psychosocial) and mothers' child rearing practices, as influenced by four selected variables (child's gender and ordinal position, mother's education, and rural or urban residence). The total sample size was 303 mothers [153 of rural residence and 150 urban] in two provinces. Mothers responded to a structured questionnaire which was read to them aloud by trained interviewers who then recorded the responses. All the mothers had children between 4-6 years old; equal numbers of male and female children were included, and the entire economic and educational ranges were represented. MANOVA results showed significant main effects of all four variables on maternal expectations of child development and on maternal child rearing practices. Also, significant interaction effects of residential location and maternal education on mothers' expectations of children's physical/perceptual motor development were found (F[2, 256]=3.05, P=0.05). Significant interaction effects also were found of maternal education and the child's ordinal position (F[4,256]=2. 95, P=0.02) on maternal expectations of children's psychosocial development.

Fatigue in mothers of infants discharged to the home on apnea monitors.

A comparative study was done to determine differences in caregiver fatigue between two groups of mothers of preterm infants at baseline, in the hospital (Time 1), 1 week postdischarge (Time 2), and 1 month postdischarge (Time 3). Group 1 infants were discharged home on apnea monitors (AM) (n = 28), and Group 2 infants were not on apnea monitors (nonAM)(n = 46). Measured by the Multidimensional Assessment of Fatigue (MAF) scale, mean fatigue scores from Time 1 to Time 3 markedly increased for the monitor group and decreased for the nonmonitor group. The scores were significantly different between the two groups at Times 2 and 3 but not at baseline. Two-way analysis of variance (ANOVA) with repeated measures showed group by time interaction effects on fatigue. Monitoring and alleviation of fatigue in home caregivers of preterm infants on apnea monitors are necessary.

Nonpeptide oxytocin antagonists: analogs of L-371,257 with improved potency.

Structure-activity studies on the oxytocin antagonist 1 (L-371,257; Ki = 9.3 nM) have led to the identification of a related series of compounds containing an ortho-trifluoroethoxyphenylacetyl core which are orally bioavailable and have significantly improved potency in vitro and in vivo, e.g., compound 8 (L-374,943; Ki = 1.4 nM).

Defining and measuring fatigue.

In response to a long history of problems with defining and measuring fatigue, the University of Kansas School of Nursing established a Center for Biobehavioral Studies of Fatigue Management to facilitate the study of fatigue in diverse populations. The purpose of this article is to review past efforts to define and measure fatigue and the conceptual problems relevant to currently used measures of fatigue. Several distinct characteristics and corresponding measures of fatigue are identified and a definition and framework for the study of fatigue are discussed. Future research on fatigue must attend to the conceptual distinctions among various measures and the measures of fatigue most appropriate to the goals of a study.