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White dwarfs are useful objects with which to study the local interstellar medium (ISM). High ionisation state absorption features that cannot be attributed to the photosphere or the ISM have been observed along the line-of-sight to a number of white dwarf stars. Suggested origins of these lines include ionisation from past supernovae, stellar winds, circumstellar disks, photoionisation from nearby hot stars or also from the white dwarf itself. In this study we consider the origin of these non-photospheric highly ionised lines in two stars towards a rarefied region of the galaxy known as the extended β CMa Tunnel. We present preliminary results from our analysis of the first of these two stars.
This article seeks to shed light on civil commitment in the context of the opioid crisis, to sketch the existing legal landscape surrounding civil commitment, and to illustrate the relevant medical, ethical, and legal concerns that policymakers must take into account as they struggle to find appropriate responses to the crisis.
Longer-lived cows tend to be more profitable and the stayability trait is a selection criterion correlated to longevity. An alternative to the traditional approach to evaluate stayability is its definition based on consecutive calvings, whose main advantage is the more accurate evaluation of young bulls. However, no study using this alternative approach has been conducted for Zebu breeds. Therefore, the objective of this study was to compare linear random regression models to fit stayability to consecutive calvings of Guzerá, Nelore and Tabapuã cows and to estimate genetic parameters for this trait in the respective breeds. Data up to the eighth calving were used. The models included the fixed effects of age at first calving and year-season of birth of the cow and the random effects of contemporary group, additive genetic, permanent environmental and residual. Random regressions were modeled by orthogonal Legendre polynomials of order 1 to 4 (2 to 5 coefficients) for contemporary group, additive genetic and permanent environmental effects. Using Deviance Information Criterion as the selection criterion, the model with 4 regression coefficients for each effect was the most adequate for the Nelore and Tabapuã breeds and the model with 5 coefficients is recommended for the Guzerá breed. For Guzerá, heritabilities ranged from 0.05 to 0.08, showing a quadratic trend with a peak between the fourth and sixth calving. For the Nelore and Tabapuã breeds, the estimates ranged from 0.03 to 0.07 and from 0.03 to 0.08, respectively, and increased with increasing calving number. The additive genetic correlations exhibited a similar trend among breeds and were higher for stayability between closer calvings. Even between more distant calvings (second v. eighth), stayability showed a moderate to high genetic correlation, which was 0.77, 0.57 and 0.79 for the Guzerá, Nelore and Tabapuã breeds, respectively. For Guzerá, when the models with 4 or 5 regression coefficients were compared, the rank correlations between predicted breeding values for the intercept were always higher than 0.99, indicating the possibility of practical application of the least parameterized model. In conclusion, the model with 4 random regression coefficients is recommended for the genetic evaluation of stayability to consecutive calvings in Zebu cattle.
The metal-catalyst-free growth of carbon nanotubes (CNTs) using chemical vapor deposition and the application in field-effect transistors (FETs) is presented. The CNT growth process used a 3-nm-thick Ge layer on SiO2 that was subsequently annealed to produce Ge nanoparticles. Raman measurements show the presence of radial breathing mode (RBM) peaks and the absence of the disorder induced D-band, indicating single walled CNTs (SWNTs) with a low defect density. The synthesized CNTs are used to fabricate CNTFETs and the best device has a state-of-the-art on/off current ratio of 3×108 and a steep sub-threshold slope of 110 mV/decade.
We analyzed nitrogen (N) content in phloem and xylem of 75 northern red oak, Quercus rubra L. (Fagaceae), removed in 2002–2007 from three sites within the Ozark National Forest, Arkansas, to investigate the relationship between vascular tissue N status and wood borer infestation. Populations of native red oak borer, Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae), experienced an outbreak and population crash during the sampling period. Vascular tissue N was not correlated with borer infestation density (exit holes/m−2/bark surface), which suggests variation in N status of vascular tissue was not influenced by or did not influence borer success. Vascular tissue N was greater in trees sampled during winter months than in trees sampled in spring and summer months.
Experimental animal studies have shown that nicotine exposure during gestation alters the expression of fetal hypothalamic neuropeptides involved in the control of appetite. We aimed to determine whether the exposure to maternal smoking during gestation in humans is associated with an altered feeding behavior of the adult offspring. A longitudinal prospective cohort study was conducted including all births from Ribeirão Preto (São Paulo, Brazil) between 1978 and 1979. At 24 years of age, a representative random sample was re-evaluated and divided into groups exposed (n = 424) or not (n = 1586) to maternal smoking during gestation. Feeding behavior was analyzed using a food frequency questionnaire. Covariance analysis was used for continuous data and the χ2 test for categorical data. Results were adjusted for birth weight ratio, body mass index, gender, physical activity and smoking, as well as maternal and subjects’ schooling. Individuals exposed to maternal smoking during gestation ate more carbohydrates than proteins (as per the carbohydrate-to-protein ratio) than non-exposed individuals. There were no differences in the consumption of the macronutrients themselves. We propose that this adverse fetal life event programs the individual's physiology and metabolism persistently, leading to an altered feeding behavior that could contribute to the development of chronic diseases in the long term.
Incidents of non-specific illness associated with the consumption of oysters have highlighted the lack of published information on the bacteriology of shellfish suitable for consumption. Investigations showed that the majority of molluscan shellfish entering English markets conform to the accepted standard of less than 5 Escherichia coli/ml. tissue. The numbers of E. coli were related to the sanitary quality of the growing area but no relation could be established between numbers of E. coli and coliforms, faecal streptococci or Clostridium welchii. The numbers of non-specific bacteria varied considerably but shellfish from sources associated with non-specific illness yielded relatively high counts at 37° C. The results showed that there was no justification for a standard based on total plate counts, which often exceeded 106/g. Such a standard would have to be coupled with spoilage or the incidence of non-specific illness. The relation between the numbers of non-specific bacteria growing at 20 and 37° C. appears to be a useful measure for assessing the likelihood that raw shellfish are a public health risk.
A collaborative survey has shown that V. parahaemolyticus is widely distributed in British coastal waters, sediments and shellfish, especially in southern and western areas. The relatively small numbers in the environment do not present significant health hazards from marine products, provided that processing, storage and distribution are adequate. The presence of this organism in small numbers in British coastal waters or in shellfish should not in itself be regarded as cause for concern.
Wild populations of the Norway rat, Rattus norvegicus, in Jutland have been known to be resistant to the anticoagulant rodenticide warfarin since 1962. The inheritance of the resistance was investigated in the F1, backcross and intercross. The results are consistent with the resistance being due to a major gene at the Rw locus. Resistant homozygotes, heterozygotes and susceptible homozygotes appeared to be distinguishable experimentally on the basis of differences in their susceptibility to vitamin K deficiency. The results are discussed in relation to previous studies of the inheritance of warfarin resistance in rats.
The inheritance of resistance to the rodenticide, warfarin, in the Norway rat, Rattus norvegicus, derived from a wild rat population in Scotland was studied in the backcross, intercross and testcross. The resistance was found to be due to a major gene with about the same map position in Linkage Group I as the warfarin-resistance gene, Rw2, which occurs in the wild rat population in Wales. In heterozygotes, the Scottish resistance gene, unlike the Welsh gene, is incompletely penetrant in expression, though the penetrance was found to increase markedly in response to selection. Differences between the Scottish and Welsh types of resistance suggest that the two resistance genes are allelic.
The frequency of monogenic resistance to anticoagulant rodenticides in Rattus norvegicus in an area straddling the England–Wales border was monitored from 1967 until 1975. Rats were trapped on farms and tested in the laboratory by administering a dose of warfarin lethal to susceptibles. The mean incidence of resistance was 44% and did not change significantly, despite the extensive use of anticoagulants by farmers during the 9-year period. In 1975 more refined techniques showed that the frequencies of susceptible (SS) and resistant (RR) homozygotes were significantly below the Hardy–Weinberg expectations and simple estimates of the relative fitness ratios for the RR, RS and SS phenotypes were 0·37, 1·0 and 0·68 respectively. In two relatively isolated valleys, where selection with anticoagulants was minimal, the frequency of resistance decreased significantly from 57% to 39% during 1973–5. The results are consistent with the hypothesis that a balanced polymorphism is being maintained. Selection against susceptible homozygotes by the use of anticoagulant rodenticides, and against the resistant homozygote due to its high susceptibility to a primary deficiency of vitamin K gives the heterozygotes a selective advantage. A number of ecological factors that influence the incidence of the resistance are discussed briefly.
Two warfarin-resistant strains of the Norway rat, Rattus norvegicus, derived independently from wild populations in Wales and Scotland and both homozygous for a major gene at the warfarin-resistance locus, Rw, were found to differ in their hypoprothrombinaemic response to simultaneous dosage with warfarin and vitamin K. The Welsh strain gave a small response and the Scottish strain a large response. These two response levels segregated in Mendelian fashion in various crosses involving the two resistant strains and a third, non-resistant strain. This indicates that the Rw locus has a series of three multiple alleles, denoted Rww, Rws and Rw+. The results are discussed briefly in relation to biochemical, ecological and evolutionary aspects of warfarin resistance.
Commission 36 covers all the physics of stellar atmospheres. The scientific activity in this large field has been very intense during the last triennium and led to the publication of a large number of papers which makes an exhaustive report practically not feasible. As a consequence we decided to keep the format of the preceding report: first a list of areas of current research, then web links for obtaining further information.
Competitive interactions among bark beetle associated fungi are potentially influenced by abiotic factors. Water potential, in particular, undergoes marked changes over the course of beetle colonization of tree hosts. To investigate the impact of water potential on competition among three southern pine beetle associated fungi, Ophiostoma minus, Entomocorticium sp. A and Ceratocystiopsis ranaculosus, we utilized artificial media with water potentials of 0, −5, −10, and −20 MPa. Growth of all three fungi, when grown alone, decreased on media with lower water potentials. Growth rates of all three fungi were likewise reduced in competition experiments. At −5 to −10 MPa, C. ranaculosus (a fungus with beneficial effects toward southern pine beetle) was nearly equal in competitive ability to O. minus (a fungus with antagonistic effects towards southern pine beetle). This was not true on control media, nor at other water potentials tested. The range of water potentials used in our assays was similar to the range of water potentials we measured in loblolly pines within a southern pine beetle infestation. This study indicates that water potential may alter the outcome of competitive interactions among bark beetle-associated fungi in ways that favour bark beetle success.
Heavy ion irradiations of single and multi walled carbon nanotubes and total ionization dose of gallium nitride nanowires were investigated. Post irradiation analyses of samples were performed with transmission and scanning electron microscopy, atomic force microscopy and micro Raman spectroscopy.
The identification of fluctuating confusion is central to improving the differential diagnosis of the common dementias.
To determine the value of two rating scales to measure fluctuating confusion.
The agreement between the clinician-rated scale and the scale completed by a non-clinician was determined. Correlations between the two scales were calculated; variability in attention was calculated on a computerised cognitive assessment and variability in delta rhythm on an electroencephalogram (EEG).
The Clinician Assessment of Fluctuation and the computerised cognitive assessment were completed for 155 patients (61 Alzheimer's disease, 37 dementia with Lewy bodies, 22 vascular dementia, 35 elderly controls). A subgroup (n=40) received a further evaluation using the One Day Fluctuation Assessment Scale and an EEG. The two scales correlated significantly with each other, and with the neuropsychological and electrophysiological measures of fluctuation.
Both scales are useful instruments for the clinical assessment of fluctuation in dementia.