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The evidence informing the management of cardiovascular risk in patients with psychiatric disorders is weak.
This cohort study used data from all patients, aged ≥ 30, registered in 140 primary care practices (n = 524,952) in London to estimate the risk of developing diabetes, hypertension, hyperlipidemia, tobacco consumption, obesity, and physical inactivity, between 2005 and 2015, for patients with a previous diagnosis of schizophrenia, depression, anxiety, bipolar or personality disorder. The role of antidepressants, antipsychotics and social deprivation in these associations was also investigated. The age at detection of cardiovascular risk factor was compared between patients with and without psychiatric disorders. Variables, for exposures and outcomes, defined from general practitioners records, were analysed using multivariate regression.
Patients with psychiatric disorders had an increased risk for cardiovascular risk factors, especially diabetes, with hazard ratios: 2.42 (2.20–2.67) to 1.31 (1.25–1.37), hyperlipidemia, with hazard ratios: 1.78 (1.60–1.97) to 1.25 (1.23–1.28), and obesity. Antidepressants, antipsychotics and social deprivation did not change these associations, except for smoking and physical inactivity. Antidepressants were associated with higher risk of diabetes, hypertension and hyperlipidemia. Antipsychotics were associated with a higher risk of diabetes. Antidepressants and antipsychotics were associated with lower risk of other risk factors. Patients with psychiatric conditions have later detection of cardiovascular risk factors. The interpretation of these results should acknowledge the lower rates of detection of risk factors in mentally ill patients.
Cardiovascular risk factors require special clinical attention among patients with psychiatric disorders. Further research could study the effect of antidepressants and antipsychotics on cardiovascular risk factors.
Ornithopters and entomopters should be insensitive to the gusty environment during outdoor operations. Hence, it becomes imperative to understand their behaviour under the influence of gust for ensuring stable flight. In light of this, the present numerical study focused on understanding the aerodynamics of flapping wings with five different planform shapes under the influence of a spatiotemporally varying frontal gust. 3D, unsteady, laminar, and incompressible Navier-Stokes equations were solved using finite volume formulation. A canonical case of asymmetric 1 degree of freedom (DoF) flapping kinematics was considered. Horizontal and vertical force patterns in constant and gusty inflow conditions were numerically computed and compared. Findings were analyzed quantitatively by comparing the differences in the instantaneous force patterns, ordinal scoring approach, and phase space plots. Qualitative comparisons were made based on plots of vortex structures and surface pressure contours for constant and gusty inflow conditions for wings with different planform shapes. Spanwise Lagrangian Coherent Structures (LCS) of all the five wings were also compared. Studies revealed that the elliptical wing exhibited low sensitivity and inverse semi-elliptical wing exhibited high sensitivity to the gusty inflow. Rectangular, triangular and semi-elliptical shaped wings were moderately sensitive to the gusty inflow. This finding, within the limitations of the flapping kinematics and simulation conditions considered for the present study, supported the fact that many natural flyers like forest raptors, non-migratory passerines, pheasants, and partridges have adopted elliptical wing planform for efficient flight.
Childhood varicella vaccination has not yet been introduced in the UK. To inform decision-making about future vaccine programmes, data on the burden of varicella in general practice over a 10-year period (01/01/2005–31/12/2014) was calculated by age and ethnicity, using anonymised data from >8 million individuals in the Clinical Practice Research Datalink. Varicella consultations peaked at 20 603 in 2007, then decreased annually in all age groups to 11 243 in 2014. Each year, consultation rates were common among infants, were highest among 1–3 year olds (61·2 consultations/1000 person-years in 2007, 39·7/1000 person-years in 2014) and then fell with increasing age to <1·0/1000 person-years at ages ⩾20 years. Varicella acquisition appeared to be delayed in some ethnic groups, with lower consultation rates for children aged <3 years but increased rates for older children and adults aged ⩽40 years among those of black African, Afro-Caribbean, South Asian or other Asian ethnicity. Decreasing general practice consultation rates over time could reflect changes in healthcare utilisation, with patients seeking care in alternative settings such as Accident and Emergency Departments, although current data prevent full assessment of this. Availability of data on varicella diagnoses across all health settings would enable estimation of the total healthcare burden due to varicella and the cost-effectiveness of introducing varicella vaccination.
Prematurity is a risk factor for hypertension, vascular stiffness, nephron deficit and adult onset cardiorenal disease. The vascular tree and kidneys share morphogenic drivers that promote maturation in utero before 36 weeks of gestation. Vascular elastin accrual terminates after birth leaving collagen to promote vascular stiffness. Our objective was to determine if the histomorphometry of the umbilical artery, an extension of the aorta, parallels nephron mass across gestational age groups. From a cohort of 54 newborns, 32 umbilical cord specimens were adequate for evaluation. The umbilical cord was sectioned, stained with trichrome, and digitalized. Muscular and collagenous areas of the umbilical artery were measured in pixels using the Image J 1.48q software. Total kidney volume was measured by ultrasound and factored by body surface area (TKV/BSA). The umbilical artery total area was significantly greater in term v. preterm infants (9.3±1.3 v. 7.0±2.0 mm2; P<0.05) and increased with gestational age; while the percent muscular and collagen areas were independent of gestational age (R2=0.04; P=ns). Percent muscular area correlated positively with TKV/BSA (r=0.53; P=0.002); while an increase in collagen correlated inversely with kidney mass (r=−0.53; P=0.002). In conclusion, an enhanced % muscular area and presumed vascular elasticity was associated with increased renal mass in all infants. Umbilical artery histomorphometry provides a link between the intrauterine environment, vascular and kidney development.
Rapid climatic and socio-economic changes challenge current agricultural R&D capacity. The necessary quantum leap in knowledge generation should build on the innovation capacity of farmers themselves. A novel citizen science methodology, triadic comparisons of technologies or tricot, was implemented in pilot studies in India, East Africa, and Central America. The methodology involves distributing a pool of agricultural technologies in different combinations of three to individual farmers who observe these technologies under farm conditions and compare their performance. Since the combinations of three technologies overlap, statistical methods can piece together the overall performance ranking of the complete pool of technologies. The tricot approach affords wide scaling, as the distribution of trial packages and instruction sessions is relatively easy to execute, farmers do not need to be organized in collaborative groups, and feedback is easy to collect, even by phone. The tricot approach provides interpretable, meaningful results and was widely accepted by farmers. The methodology underwent improvement in data input formats. A number of methodological issues remain: integrating environmental analysis, capturing gender-specific differences, stimulating farmers' motivation, and supporting implementation with an integrated digital platform. Future studies should apply the tricot approach to a wider range of technologies, quantify its potential contribution to climate adaptation, and embed the approach in appropriate institutions and business models, empowering participants and democratizing science.
Studies have linked ethnic differences in depression rates with neighbourhood ethnic density although results have not been conclusive. We looked at this using a novel approach analysing whole population data covering just over one million GP patients in four London boroughs.
Using a dataset of GP records for all patients registered in Lambeth, Hackney, Tower Hamlets and Newham in 2013 we investigated new diagnoses of depression and antidepressant use for: Indian, Pakistani, Bangladeshi, black Caribbean and black African patients. Neighbourhood effects were assessed independently of GP practice using a cross-classified multilevel model.
Black and minority ethnic groups are up to four times less likely to be newly diagnosed with depression or prescribed antidepressants compared to white British patients. We found an inverse relationship between neighbourhood ethnic density and new depression diagnosis for some groups, where an increase of 10% own-ethnic density was associated with a statistically significant (p < 0.05) reduced odds of depression for Pakistani [odds ratio (OR) 0.81, 95% confidence interval (CI) 0.70–0.93], Indian (OR 0.88, CI 0.81–0.95), African (OR 0.88, CI 0.78–0.99) and Bangladeshi (OR 0.94, CI 0.90–0.99) patients. Black Caribbean patients, however, showed the opposite effect (OR 1.26, CI 1.09–1.46). The results for antidepressant use were very similar although the corresponding effect for black Caribbeans was no longer statistically significant (p = 0.07).
New depression diagnosis and antidepressant use was shown to be less likely in areas of higher own-ethnic density for some, but not all, ethnic groups.
Stars are changing entities in a constant evolution during their lives. At non-secular time scales – from seconds to years – the effect of dynamical processes such as convection, rotation, and magnetic fields can modify the stellar oscillations. Convection excites acoustic modes in solar-like stars, while rotation and magnetic fields can perturb the oscillation frequencies, lifting the degeneracy in the azimuthal component m of the eigenfrequencies (see Chapter 9 for the case in which rotation is slow and first-order perturbative theory can be used). Moreover, the interaction between rotation, convection, and magnetic fields can produce magnetic dynamos, which sometimes yield to regular magnetic activity cycles.
In this chapter we review how stellar dynamics can be studied and explain what long-term seismic observations can bring to the understanding of this field. Thus, we show how we can study some properties of the convective time scales operating in a star like the Sun. We also compare the stratified information we can obtain on the internal (radial) differential rotation from main-sequence solar-like stars to the Sun, and to more evolved subgiants and giants. We complement this information on the internal rotation with the determination of the surface (latitudinal differential) rotation obtained directly from the lightcurves. Indeed, when stars are active there can be spots on their surfaces dimming the light emitted. When the star rotates, the emitted light will be modulated by the presence of these spots with a period corresponding to the rotation rate at the active latitudes (where the spots develop). We finally give a brief summary of stellar magnetic studies based on spectroscopic observations and then we discuss the use of seismology to better understand the stellar magnetism of solar-like stars and the existence of possible magnetic cycles. We conclude this chapter by discussing the seismology of fast rotating stars and, from a theoretical point of view, what are the current challenges to infer properties of the internal structure and dynamics of intermediate-and high-mass stars.
An inline metal organic chemical vapor deposition system was used to deposit tin sulfide at temperatures >500 °C. Tetramethyltin was used as the tin source and diethyldisulfide as the sulfur source. An overhead injector configuration was used delivering both precursors directly over the substrate. The tin and sulfur precursors were premixed before injection to improve chemical reaction in the gas phase. Growth temperatures 500 – 540 °C were employed producing films with approximate 1:1 stoichiometry of Sn and S detected by energy dispersive x-ray spectroscopy. X-ray diffraction showed there to be mixed phases with Sn2S3 present with SnS.
We investigate the synthesis of kesterite Cu2ZnSnS4 (CZTS) thin films using thermal evaporation from copper, zinc and tin pellets and post-annealing in a sulfur atmosphere. The effects of chemical composition were studied both on the absorber layer properties and on the final solar cell performance. It is confirmed that CZTS thin film chemical composition affects the carrier concentration profile, which then influences the solar cell properties. Solar cells using a CZTS thin film with composition ratio Cu/(Zn+Sn) = 0.87, and Zn/Sn = 1.24 exhibited an open-circuit voltage of 483 mV, a short-circuit current of 14.54 mA/cm2, a fill factor of 37.66 % and a conversion efficiency of 2.64 %. Only a small deviation from the optimal chemical composition can drop device performance to a lower level, which confirms that the CZTS solar cells with high conversion efficiency existed in a relatively narrow composition region.
CuInS2 (CIS) quantum dots (QDs) with different diameters were prepared and their optical properties were studied. The optical band gap of QDs, as estimated by absorption spectrum, was found to decrease with increase in size. The stokes shift between absorption and photoluminescence peaks was observed to be larger (>100 meV) in all the three samples. This shows that the defect states available in the forbidden gap dominates the recombination mechanism. The variation in the emission peak with QD size, however, indicates that the relaxation dynamics in CIS QDs involves both excitonic level as well as the defect states.
Due to the rapid advance of the emergence of resistant microorganisms to different antibiotics, there is a need to create new antimicrobial agents. It is possible that Nanotechnology has a great impact in this area since the nanoparticles can improve the antimicrobial effect of the antibiotics. In this study we used three different metal oxides nanoparticles, the MgO, ZnO and CuO. These nanoparticles were selected because their interactions leading to cell death and their optical properties. The aim of this study is to develop new methods that are more effective against resistance bacteria, developing antibacterial agents using different nanoparticles against Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 10145), and Staphylococcus aureus (ATCC BAA-1026). This study was conducted to evaluate the antibacterial effects of a combination of nanoparticles together with different concentrations of three antibiotics, Gentamicin, Cephalexin and Co-Trimoxazole. The results showed that some nanoparticles are effective to inhibit growth in these microorganisms by increasing the effectiveness of the antibiotic. Therefore, the present study indicates that the combination of the nanoparticles with antibiotics may be applicable as a new antimicrobial agent.
Methods of improving low-cost Cu2O|ZnO heterojunction diodes fabricated through galvanostatic deposition of Cu2O are presented. Improved processing parameters responsible for maximizing built-in voltage (Vbi) are determined. The relationship between pH, deposition current, temperature, and diode quality is analyzed and a process window for optimal Cu2O deposition on ZnO is obtained with a pH range between 12.0 and 12.1 and a current density range which is determined by the effect of both pH and deposition current (Jdep) on grain size. The pH window is found to be narrower than previously reported1 and much narrower than the processing window for the deposition of Cu2O films. A two-step approach deposition based on the use of different Jdep is presented for the first time. A Vbi of 0.6 V is achieved, which is the highest reported for cells produced using low temperature processing routes involving electrodeposition and reactive sputtering.
Transparent conducting cadmium tin oxide (CTO) thin films were obtained from a mixture of CdO and SnO2 precursor solutions by the dip-coating sol-gel technique. The thin films studied in this work were made with 7 coats (∼200 nm) on corning glass and quartz substrates. Each coating was deposited at a withdrawal speed of 2 cm/min, dried at 100°C for 1 hour and then sintered at 550°C for 1 hour in air. In order to decrease the resistivity values of the films, these were annealed in a vacuum atmosphere and another set of films were annealed in an Ar/CdS atmosphere. The annealing temperatures (Ta) were 450°C, 500°C and 550°C, as well as 600°C and 650°C, when corning glass and quartz substrates were used, respectively. X-Ray diffraction (XRD) patterns of the films annealed in a vacuum showed that there is only the presence of CTO crystals for 450°C≤ Ta ≤ 600°C and CTO+SnO2 crystals for Ta=650°C. The films annealed in Ar/CdS atmosphere were only constituted of CTO crystals independent of the Ta. The minimum resistivity value obtained was ∼4 x 10-4 Ωcm (Rsheet= 20 Ω/□) for the films deposited on quartz and annealed at Ta=600°C under an Ar/CdS atmosphere. The films deposited on quartz showed the higher optical transmission (∼90%) with respect to the films deposited on corning glass substrates (∼85%) in the Uv-vis region. For their optical and electrical characteristics, these films are good candidates as transparent electrodes in solar cells.
The dynamo process is believed to drive the magnetic activity of stars like the Sun that have an outer convection zone. Large spectroscopic surveys showed that there is a relation between the rotation periods and the cycle periods: the longer the rotation period is, the longer the magnetic activity cycle period will be. We present the analysis of F stars observed by Kepler for which individual p modes have been measure and with surface rotation periods shorter than 12 days. We defined magnetic indicators and proxies based on photometric observations to help characterise the activity levels of the stars. With the Kepler data, we investigate the existence of stars with cycles (regular or not), stars with a modulation that could be related to magnetic activity, and stars that seem to show a flat behaviour.
Nanofluids are nano-size-powder suspensions in liquids that are of interest for their enhanced thermal transport properties. They are studied as promising alternatives as compared to ordinary cooling fluids, but the effects of nanofluids on wall materials are largely unknown. The authors developed an instrument that uses a low-speed jet on material targets to test such effects.
The work is presented of the authors’ experimental research on the early interactions of selected nanofluids (2% weight of alumina nanopowders in distilled water, and in solutions of ethylene glycol in water) with aluminum and copper samples as typical cooling-system materials. The observed surface changes (and possible nanoparticle deposition) for test periods as long as 14 hours were assessed by roughness and volumetric-removal wear measurements, and by microscope studies. Comparative roughness measurements indicate that alumina nanofluids in water and ethylene glycol solutions can start surface changes on aluminum surfaces, but show no effects on copper for the same testing conditions. These investigations set a baseline for further research and provide a suitable method for the testing of nanofluids effects in cooling system-materials.
Bulk structures of un-stabilized ZrO2-x with x in the 0 ≤ x ≤ 0.44 range under ambient pressure exist in three different structures (monoclinic, tetragonal and cubic). At ambient temperature and elevated pressures above 3.5 GPa, zirconia, at these compositions, a fourth phase is found, the orthorhombic structure. A dilute sol-gel method was used to produce nanoscale zirconia particles containing the unstabilized orthorhombic cotunnite structure for use in this project. Extensive characterization of this material indicates that the critical factor in determining the synthesized structures appears to be the number and placement of oxygen vacancies. These results also indicate that surface energy alone is not the controlling factor in determining the crystal structure synthesized.
Today, different analytical methods are used by different laboratories to quantify androstenone in fat tissue. This study shows the comparison of methods used routinely in different laboratories for androstenone quantification: Time-resolved fluoroimmunoassay in Norwegian School of Veterinary Science (NSVS; Norway), gas chromatography coupled to mass spectrometry in Co-operative Central Laboratory (CCL; The Netherlands) and in Institut de Recerca i Tecnologia Agroalimentàries (IRTA; Spain), and high-pressure liquid chromatography in Agroscope Liebefeld-Posieux Research Station (ALP; Switzerland). In a first trial, a set of adipose tissue (AT) samples from 53 entire males was sent to CCL, IRTA and NSVS for determination of androstenone concentration. The average androstenone concentration (s.d.) was 2.47 (2.10) μg/g at NSVS, 1.31 (0.98) μg/g at CCL and 0.62 (0.52) μg/g at IRTA. Despite the large differences in absolute values, inter-laboratory correlations were high, ranging from 0.82 to 0.92. A closer look showed differences in the preparation step. Indeed, different matrices were used for the analysis: pure fat at NSVS, melted fat at CCL and AT at IRTA. A second trial was organised in order to circumvent the differences in sample preparation. Back fat samples from 10 entire males were lyophilised at the ALP labortary in Switzerland and were sent to the other laboratories for androstenone concentration measurement. The average concentration (s.d.) of androstenone in the freeze-dried AT samples was 0.87 (0.52), 1.03 (0.55), 0.84 (0.46) and 0.99 (0.67) μg/g at NSVS, CCL, IRTA and ALP, respectively, and the pairwise correlations between laboratories ranged from 0.92 to 0.97. Thus, this study shows the influence of the different sample preparation protocols, leading to major differences in the results, although still allowing high inter-laboratory correlations. The results further highlight the need for method standardisation and inter-laboratory ring tests for the determination of androstenone. This standardisation is especially relevant when deriving thresholds of consumer acceptance, whereas the ranking of animals for breeding purposes will be less affected due to the high correlations between methods.
In this work, we studied metal/SnO2 junctions using transport properties. Parameters such as barrier height, ideality factor and series resistance were estimated at different temperatures. Schottky barrier height showed a small deviation of the theoretical value mainly because the barrier was considered fixed as described by ideal thermionic emission-diffusion model. These deviations have been explained by assuming the presence of barrier height inhomogeneities. Such assumption can also explain the high ideality factor as well as the Schottky barrier height and ideality factor dependence on temperature.
Conventional material synthesis procedures rely on the intrinsic chemical behaviours (e.g., different hydrolysis rates of the reactants in solution phase reactions or different vapour pressure or thermal stability in the gas phase reactions) of the different components, which make the material properties susceptible to inaccuracies due to an increased number of process variables. As a consequence, phase separation and element segregation are present at the nanometer scale, although the global stoichiometry of the product may correspond to the desired composition. In this context, the use of well-defined molecular precursors is a promising approach to grow extended solid-state structures from atomic constituents.