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Why patients with psychosis use cannabis remains debated. The self-medication hypothesis has received some support but other evidence points towards an alleviation of dysphoria model. This study investigated the reasons for cannabis use in first-episode psychosis (FEP) and whether strength in their endorsement changed over time.
FEP inpatients and outpatients at the South London and Maudsley, Oxleas and Sussex NHS Trusts UK, who used cannabis, rated their motives at baseline (n = 69), 3 months (n = 29) and 12 months (n = 36). A random intercept model was used to test the change in strength of endorsement over the 12 months. Paired-sample t-tests assessed the differences in mean scores between the five subscales on the Reasons for Use Scale (enhancement, social motive, coping with unpleasant affect, conformity and acceptance and relief of positive symptoms and side effects), at each time-point.
Time had a significant effect on scores when controlling for reason; average scores on each subscale were higher at baseline than at 3 months and 12 months. At each time-point, patients endorsed ‘enhancement’ followed by ‘coping with unpleasant affect’ and ‘social motive’ more highly for their cannabis use than any other reason. ‘Conformity and acceptance’ followed closely. ‘Relief of positive symptoms and side effects’ was the least endorsed motive.
Patients endorsed their reasons for use at 3 months and 12 months less strongly than at baseline. Little support for the self-medication or alleviation of dysphoria models was found. Rather, patients rated ‘enhancement’ most highly for their cannabis use.
In recent years the association between sexual dysfunction (SD) and obesity in the general population has drawn major attention. Although sexual dysfunction is common in psychosis, its relationship with weight gain and obesity remains unclear.
To investigate the association between sexual dysfunction and obesity in a cohort of patients with first episode psychosis.
Sexual function was assessed in a cohort of patients with first episode psychosis using the Sexual Function Questionnaire (SFQ). Anthropometric measures, including weight, BMI, waist, waist–hip ratio were investigated. Additionally, leptin and testosterone were investigated in male patients.
A total of 116 patients (61 males and 55 females) were included. Of these 59% of males and 67.3% of females showed sexual dysfunction (SD) according to the SFQ. In males, higher SFQ scores were significantly correlated with higher BMI (Std. β = 0.36, P = 0.01), higher leptin levels (Std. β = 0.34, P = 0.02), higher waist–hip ratio (Std. β = 0.32, P = 0.04) and lower testosterone levels (Std. β = −0.44, P = 0.002). In contrast, in females, SFQ scores were not associated with any of these factors.
While sexual dysfunction is present in both female and male patients with their first episode of psychosis, only in males is sexual dysfunction associated with increased BMI and waist–hip ratio. The association between SD, BMI, low levels of testosterone and high levels of leptin suggest that policies that lead to healthier diets and more active lifestyles can be beneficial at least, to male patients.
High-resolution radio maps of supernova remnants (SNRs) are indispensable for distinguishing the more common shell remnants from the centrally concentrated (Crab-like) remnants; such studies also reveal any departures from symmetry, and this can yield vital information concerning interaction of the ejecta with the surrounding interstellar medium.
PKS 1318-43 was first identified with the elliptical galaxy NGC 5090 by Ekers (1969) in the Parkes catalogue. Schilizzi and McAdam (1975) mapped the source with 2.9 arcmin resolution at 408 MHz using the Mills Cross, resolving the source into an extended double structure approximately 15 arcmin in extent at p.a. 36°. Schilizzi (1975) also noted a possible optical link with an edge-on spiral (NGC 5091) ~75 arcsec to the south-east. Figure 1 shows a print of the two galaxies taken from the UK Schmidt J survey film. During 1980, in collaboration with K. J. Wellington, RMS mapped the source at 1415 MHz with the Fleurs Synthesis Telescope (FST, Christiansen 1973).
Spring wheat varieties with the Sm1 gene for resistance to wheat midge, Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae), were compared with susceptible wheat (Triticum Linnaeus; Poaceae) with respect to sources of yield loss and reduction in market value from wheat midge feeding damage. Four resistant varietal blends (90% Sm1 wheat plus 10% susceptible refuge) and four susceptible cultivars were grown in replicated experiments at eight locations in western Canada. Frequencies and 1000-kernel weights of undamaged and midge-damaged seeds were assessed before harvest by dissecting samples of ripe spikes, and after harvest in samples of cleaned grain. Spike data were used to estimate yield losses from reduced weight of damaged seeds and loss of severely damaged seeds (⩽8 mg) at harvest. Among midge-damaged seeds in spikes, few were severely damaged in resistant varietal blends, whereas most were severely damaged in susceptible cultivars. Cleaned, harvested grain of resistant varietal blends and susceptible cultivars had similar frequencies of midge damage and were assessed similar market grades. The primary benefit of midge-resistant wheat was reduced yield loss due to seed damage by wheat midge larvae. Resistant wheat did not protect against loss of market grade, but market value could increase due to larger yields.
In 1948 Josiah Russell published what was a remarkably innovative study in the demographic history of medieval England. It principally involved exploitation of evidence in the Domesday Survey, bishops' registers, an array of manorial extents, the poll taxes and the inquisitions post mortem. Russell's approach displayed a competence in demographic methodology that was unusual, indeed precocious, for a historian of population at this time. The book, one could claim, was unique in an era that pre-dated the formal emergence of historical demography in the 1960s by almost three decades. It revealed a striking willingness to experiment with formal demographic methodology on sources that had never been created with the purpose of recording the flow of vital events or measuring demographic stocks. While over the years its shortcomings have been exposed, it contains much material that is of immense value for medieval English demographic analysis. Its findings continue to be cited and none more so than the estimates Russell made of life expectancy of the tenants-in-chief of the crown based upon the inquisitions post mortem (IPMs). In this chapter the focus will be on Russell's use of the IPMs in the form of a reassessment of his approaches with a view to establishing means of refining estimates of adult life expectancy and the seasonality of mortality from these sources.
The McMurdo Dry Valleys are among the driest, coldest environments on Earth and are excellent analogues for the Martian northern plains. In preparation for the 2008 Phoenix Mars mission, we conducted an interdisciplinary investigation comparing the biological, mineralogical, chemical, and physical properties of wetter lower Taylor Valley (TV) soils to colder, drier University Valley (UV) soils. Our analyses were performed for each horizon from the surface to the ice table. In TV, clay-sized particle distribution and less abundant soluble salts both suggested vertical and possible horizontal transport by water, and microbial biomass was higher. Alteration of mica to short-order phyllosilicates suggested aqueous weathering. In UV, salts, clay-sized materials, and biomass were more abundant near the surface, suggesting minimal downward translocation by water. The presence of microorganisms in each horizon was established for the first time in an ultraxerous zone. Higher biomass numbers were seen near the surface and ice table, perhaps representing locally more clement environments. Currently, water activity is too low to support metabolism at the Phoenix site, but obliquity changes may produce higher temperatures and sufficient water activity to permit microbial growth, if the populations could survive long dormancy periods (∼106 years).
Polystannanes, i.e. organometallic polymers of the chemical formula (SnR2)n, are relatively little explored, although they belong to the rare examples of polymers which are characterized by a backbone of metal atoms which are linked by covalent bonds. We developed a new synthetic route which yields pure linear poly(dibutylstannane) [Sn(Bu)2]n by polymerization of dibutylstannane (dibutyltin dihydride) with the catalyst [RhCl(PPh3)3]. Here, we report that the conversion and the reaction rate of dibutylstannane depends crucially on the temperature and [RhCl(PPh3)3] is also suited for the polymerization of dioctylstannane and didodecylstannane. The polymers thus obtained were characterized by 1H, 13C and 119Sn NMR spectroscopy: Orientation of all polystannanes was achieved by tensile drawing. The orientation was examined by UV-vis spectroscopy with polarized light and X-ray diffraction. Remarkably, the orientation of the backbone depended on the length of the alkyl groups.
The one-dimensional free energy model for ferroelectric materials developed in [1-3] is general-ized to two dimensions. The proposed two-dimensional energy potential consists of four energy wells corresponding to four variants of the material, four saddle points representing the barriers for 900 switching processes, and a local energy maximum across which 1800-switching processes take place. The free energy potential is combined with the evolution equations based on the theory of thermally activated processes. The prediction of the model is compared with the recent measurements on a Ba- TiO3 single crystalline ferroelectric in . The responses of the model at various loading frequencies are calculated and the kinetics of 900 and 1800 switching processes are discussed.
This paper addresses the development of an energy-based characterization framework which quantifies stress-induced dipole switching in ferroelectric materials. Helmholtz and Gibbs energy relations that accommodate 90° and 180° dipole orientations as equilibrium states are constructed at the lattice level. For regimes in which thermal relaxation mech- anisms are negligible, minimization of the Gibbs relations provides local polarization and strain relations. Alternatively, behavior such as creep or thermal relaxation can be incorpo- rated by balancing Gibbs and relative thermal energies through Boltzmann principles. In the nal step of the development, stochastic homogenization techniques based on the assump- tion that parameters such as coercive and induced elds are manifestations of underlying distributions are employed to construct macroscopic models suitable for nonhomogeneous polycrystalline compounds. Attributes and limitations of the model are illustrated through comparison with experimental PLZT data.
Self-extinguishing PMMA/Clay nanocomposites with conventional flame retardant agents, decabromodiphenyl oxide (DB) and antimony trioxide (AO) have been prepared by melt blending using Brabender. The combustion behavior was first investigated by subjecting slabs of the polymer to UL-94 V0 testing. We found that the polymers with only the retardant agents or the clay could not pass. On the other hand all polymers with both components were self-extinguishing. DMA results show that the introduction of 5 wt% clay improves PMMA bending modulus by 28 % and increases Tg by 8 °C. the addition of clay can effectively avoid dripping during burning test. Based on the cone calorimeter data, the general mechanism is proposed that the synergy between the char formation promoted by the clay in condense phase and free radical capture in gas phase due to the DB and AO makes the material become self-extinguishing.
The objective of this paper is to review various solid state NMR techniques that have been, or can be used for the structural characterization of siloxane—oxide hybrid systems prepared by sol-gel process, and to discuss the type of information they provide, as well as their limitations. More precisely, this paper focuses on NMR techniques to probe and quantify the different types of oxo-bridges (M–O–M of oxide network, Si–O–Si of siloxane chains and Si–O–M siloxane–MxOy interface) in siloxane-oxide nanocomposites prepared through hydrolysis and condensation of organosilanes and M(OR)n alkoxides. In addition the influence of the functionality of the silicon alkoxides and the nature of the MxOy oxides on the extent of the Si-O-M interface will be examined.
The Two Micron All Sky Survey (2MASS) provides an unprecedented, uniform photometric data set for large samples of AGN discovered at other wavelengths, and also forms the basis to search for previously unknown, obscured AGN. We present the results of a highly efficient near infrared color-based AGN survey using 2MASS that has already discovered 485 new, red AGN and QSOs. The extrapolated surface density of the 2MASS red AGN is ~0.57 deg~−2 for Ks≤15.5 mag. The ratio of Type 1 to Type 2 AGN among the newly discovered objects is 4:1, similar to proportions found in X-ray and deep ISO surveys, but the inverse of that found in IRAS surveys. The median redshift of the the new 2MASS red AGN sample is z<0.22, and all but three have z<0.7. The color distribution, polarization and X-ray properties data suggest that most of the 2MASS-discovered AGN are red because of obscuration by dust in and around their nuclei.
Fermentation of the increasingly energy-dense rations offered to meet the nutrient demands of today's high yielding dairy cows ought to adversely rumen fibre degradation. Not only could rumen fluid pH be depressed below that assumed critical to cellulolysis for extended periods of time but the quantity of readily fermentable carbohydrate available will further exacerbate this effect. These, together with the reduced rumen retention time of feed particles associated with high feeding levels could significantly limit fibre degradation. This in vitro study was designed to identify the pH at which degradation becomes impaired, the extent of this depression and whether the effect varies according to the feedstuffs offered.
Recent results on the determination of the shape of the faint end of the galaxy luminosity function in rich clusters are discussed. There is increasing evidence that in many cases the faint end of the function is steep, indicating a large population of dwarf, possibly low surface-brightness, galaxies. In addition, the magnitude at which the turn-up appears is approximately constant with richness and distance. However, it is clear that not all clusters show such a feature.
The semi-automated Reading Pressure Technique (RPT, Mauricio et al. 1998) combines gas production profiles and both rate and extent of degradation to evaluate feedstuffs in vitro. The simplicity, low initial cost and high capacity of the system (75 treatments with 4 replicates plus controls can be examined per run) allow it to be widely applied. However, and in common with many other in vitro systems, little information had been generated regarding either its sensitivity or precision. This paper describes how pure substrates were used to identify the minimum amount of fermentable material required to develop distinct degradation profiles. Substitution techniques examined whether changes in degradability at either the mono- or polysaccharide level could be detected and quantified, and replication of these studies provided data regarding precision of the system.