Modelling primary health care use: a panel zero inflated interval regression approach

We introduce the (panel) zero-inflated interval regression (ZIIR) model, to investigate GP visits using individual-level data from the British Household Panel Survey. The ZIIR is particularly suitable for this application as it jointly estimates the probability of visiting the GP and then, conditional on visiting, the frequency of visits (defined by given numerical intervals in the data). The results show that different socio-economic factors influence the probability of visiting the GP and the frequency of visits

Garnet–monazite rare earth element relationships in sub-solidus metapelites: a case study from Bhutan

A key aim of modern metamorphic geochronology is to constrain precise and accurate rates and timescales of tectonic processes. One promising approach in amphibolite and granulite-facies rocks links the geochronological information recorded in zoned accessory phases such as monazite to the pressure–temperature information recorded in zoned major rock-forming minerals such as garnet. Both phases incorporate rare earth elements (REE) as they crystallize and their equilibrium partitioning behaviour potentially provides a useful way of linking time to temperature. We report REE data from sub-solidus amphibolite-facies metapelites from Bhutan, where overlapping ages, inclusion relationships and Gd/Lu ratios suggest that garnet and monazite co-crystallized. The garnet–monazite REE relationships in these samples show a steeper pattern across the heavy (H)REE than previously reported. The difference between our dataset and the previously reported data may be due to a temperature-dependence on the partition coefficients, disequilibrium in either dataset, differences in monazite chemistry or the presence or absence of a third phase that competed for the available REE during growth. We urge caution against using empirically-derived partition coefficients from natural samples as evidence for, or against, equilibrium of REE-bearing phases until monazite–garnet partitioning behaviour is better constrained

Why Stay? A Phenomenological Look at Special Education Teacher Retention

This phenomenological study examined the teaching experiences of veteran special education teachers (SETs) and why they chose to remain in a special education teaching setting. Guided by Bronfenbrenner’s ecological systems framework, veteran SETs were interviewed and asked to describe the experiences and situations that have influenced their decision to remain in special education. Three themes and two sub-categories emerged as their motivation for persevering: (A) a calling from above, (B) standing up for the underdog, (b) personally committed to my kids, my babies, (C) beating the bushes with the apathetic, (c) against my ethical judgment. Specific information related to these themes is reported with implications for hiring practices of special education teachers and future special education teacher retention/attrition research

Radio Source Measurements at 960 MC/S

The major surveys of radio sources made at meter wavelengths have shown a disquieting lack of agreement, and an independent study of these sources using as simple an antenna as possible seems to be desirable. As a partial step in this direction, we report here a study of 106 radio sources made with one of the equatorially-mounted 90-foot paraboloids of the Owens Valley Radio Observatory. This investigation was made at a frequency of 960 Mc/s. The primary result of the study is a reliable catalog of sources which will be used as a 'finding list' for precise position measurements which are currently being undertaken with the two antennas operating as an interferometer. In addition, however, the results provide valuable information on the spectra of the sources, and have also been used in a search for optical counterparts to the sources. Ninety of the objects observed were taken from the Third Cambridge Survey (3C), which was kindly made available to us by the authors prior to publication. The remaining 16 objects in the present list were either taken from other catalogs or were discovered in the course of the present investigation. The equipment is briefly described in Section II, and in Sections III and IV the methods of determining the position and intensity of the sources are outlined. In Section V suggested optical identifications are discussed, while Section VI is devoted to a consideration of the spectra of the sources. The positions, intensities, spectral indices, and other pertinent data for the 106 sources are collected in Table I

Do environmental concerns affect commuting choices? Hybrid choice modelling with household survey data

In order to meet their ambitious climate change goals governments around the world will need to encourage behaviour change as well as technological progress; and in particular they need to weaken our attachment to the private car. A prerequisite to designing effective policy is a thorough understanding of the factors that drive behaviours and decisions. In an effort to better understand how the public’s environmental attitudes affect their behaviours we estimate a hybrid choice model (HCM) for commuting mode choice using a large household survey data set. HCMs combine traditional discrete choice models with a structural equation model to integrate latent variables, such as attitudes and other psychological constructs, into the choice process. To date HCMs have been estimated on small bespoke data sets, beset with problems of sample selection, focusing effects and limited generalizability. To overcome these problems we demonstrate the feasibility of using this valuable modelling approach with nationally representative data. Our estimates suggest that environmental attitudes and behaviours are separable constructs, and both have an important influence on commute mode choice. These psychological factors can be exploited by governments looking to add to their climate change policy toolbox in an effort to change travel behaviours

Evolution of the melt source during protracted crustal anatexis: An example from the Bhutan Himalaya

The chemical compositions of magmatic zircon growth zones provide powerful insight into evolving magma compositions due to their ability to record both time and the local chemical environment. In situ U-Pb and Hf isotope analyses of zircon rims from Oligocene–Miocene leucogranites of the Bhutan Himalaya reveal, for the first time, an evolution in melt composition between 32 and 12 Ma. The data indicate a uniform melt source from 32 Ma to 17 Ma, and the progressive addition of an older source component to the melt from at least ca. 17 Ma. Age-corrected εHf ratios decrease from between –10 and –15 down to values as low as –23 by 12 Ma. Complementary whole-rock Nd isotope data corroborate the Hf data, with a progressive decrease in εNd(t) from ca. 18 to 12 Ma. Published zircon and whole-rock Nd data from different lithotectonic units in the Himalaya suggest a chemical distinction between the younger Greater Himalayan Series (GHS) and the older Lesser Himalayan Series (LHS). The time-dependent isotopic evolution shown in the leucogranites demonstrates a progressive increase in melt contribution from older lithologies, suggestive of increasing LHS involvement in Himalayan melting over time. The time-resolved data are consistent with LHS material being progressively accreted to the base of the GHS from ca. 17 Ma, facilitated by deformation along the Main Central thrust. From 17 Ma, decompression, which had triggered anatexis in the GHS since the Paleogene, enabled melting in older sources from the accreted LHS, now forming the lowermost hanging wall of the thrust

Clinical investigation of an outbreak of alveolitis and asthma in a car engine manufacturing plant

Background Exposure to metal working fluid (MWF) has been associated with outbreaks of EAA in the US, with bacterial contamination of MWF being a possible cause, but was uncommon in the UK. Twelve workers developed extrinsic allergic alveolitis (EAA) in a car engine manufacturing plant in the UK, presenting clinically between December 2003 and May 2004. This paper reports the subsequent epidemiological investigation of the whole workforce. This had three aims:- • To measure the extent of the outbreak by identifying other workers who may have developed EAA or other work-related respiratory diseases. • To provide case-detection so that those affected can be treated. • To provide epidemiological data to identify the cause of the outbreak. Methods The outbreak was investigated in a three-phase cross-sectional survey of the workforce. Phase I A respiratory screening questionnaire was completed by 808/836 workers (96.7%) in May 2004. Phase II 481 employees with at least one respiratory symptom on screening and 50 asymptomatic controls were invited for investigation at the factory in June 2004. This included a questionnaire, spirometry and clinical opinion. 454/481(94.4%) responded along with 48/50(96%) controls. Workers were identified who needed further investigation and serial measurements of peak expiratory flow (PEF). Phase III 162 employees were seen at the Birmingham Occupational Lung Disease clinic. 198 employees returned PEF records, including 141 of the 162 who attended for clinical investigation. Case definitions for diagnoses were agreed. Results 87 workers (10.4% of workforce) met case definitions for occupational lung disease, comprising EAA(19), occupational asthma(74) and humidifier fever(7). 12 workers had more than one diagnosis. The peak onset of work-related breathlessness was Spring 2003. The proportion of workers affected was higher for those using metal working fluid (MWF) from a large sump(27.3%) compared with working all over the manufacturing area (7.9%) (OR=4.39,p<0.001). Two workers had positive specific provocation tests to the used but not the unused MWF solution. Conclusions Extensive investigation of the outbreak of EAA detected a large number of affected workers, not only with EAA but also occupational asthma. This is the largest reported outbreak in Europe. Mist from used MWF is the likely cause. In workplaces using MWF, there is a need to carry out risk assessments, to monitor and maintain fluid quality, to control mist and to carry out respiratory health surveillance