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Karlsruhe Institute of Technology (KIT) is doing research and development in the field of megawatt-class radio frequency (RF) sources (gyrotrons) for the Electron Cyclotron Resonance Heating (ECRH) systems of the International Thermonuclear Experimental Reactor (ITER) and the DEMOnstration Fusion Power Plant that will follow ITER. In the focus is the development and verification of the European coaxial-cavity gyrotron technology which shall lead to gyrotrons operating at an RF output power significantly larger than 1 MW CW and at an operating frequency above 200 GHz. A major step into that direction is the final verification of the European 170 GHz 2 MW coaxial-cavity pre-prototype at longer pulses up to 1 s. It bases on the upgrade of an already existing highly modular short-pulse (ms-range) pre-prototype. That pre-prototype has shown a world record output power of 2.2 MW already. This paper summarizes briefly the already achieved experimental results using the short-pulse pre-prototype and discusses in detail the design and manufacturing process of the upgrade of the pre-prototype toward longer pulses up to 1 s.
Suicide has been decreasing over the past decade. However, we do not know whether socioeconomic inequality in suicide has been decreasing as well.
We assessed recent trends in socioeconomic inequalities in suicide in 15 European populations.
The DEMETRIQ study collected and harmonised register-based data on suicide mortality follow-up of population censuses, from 1991 and 2001, in European populations aged 35–79. Absolute and relative inequalities of suicide according to education were computed on more than 300 million person-years.
In the 1990s, people in the lowest educational group had 1.82 times more suicides than those in the highest group. In the 2000s, this ratio increased to 2.12. Among men, absolute and relative inequalities were substantial in both periods and generally did not decrease over time, whereas among women inequalities were absent in the first period and emerged in the second.
The World Health Organization (WHO) plan for ‘Fair opportunity of mental wellbeing’ is not likely to be met.
This paper presents a fully-integrated direct-conversion fundamentally-operated mixer-first quadrature receiver module with a tunable LO in the 219–266 GHz band. It has been implemented in a 0.13-μm SiGe heterojunction bipolar transistor technology. It includes an on-chip LO path driven externally from the printed circuit board (PCB) connector level at 13.6–16.7 GHz. A hybrid coupler generates the quadrature LO signal, which drives a pair of double-balanced fundamentally-operated down-conversion mixers, whose RF ports are connected to a wideband lens-integrated on-chip ring antenna. The chip-on-lens assembly is placed in the recess of a high-speed PCB and wire-bonded. To compensate the inductive behavior of the wire-bond interconnection between the chip and the PCB at the high-speed IF outputs, an on-board 8-section step-impedance low-pass filter has been implemented. The module shows a 47 GHz 3-dB radio frequency/local oscillator operation bandwidth (BW), a peak conversion gain of 7.8 dB, a single-side-band noise figure of 11.3 dB, and a 3-dB IF BW of 13 GHz. The in-phase and quadrature amplitude imbalance stays below 1.58 dB for the 210–280 GHz band. The down-conversion and the baseband stages consume together 75.5 mW, while the LO path 378 mW. The maximum data-rate achieved with this receiver in combination with the transmitter presented in [1–3] is 60 Gbps for quadrature phase shift keying modulation.
Patients with advanced otosclerosis can present with hearing thresholds eligible for cochlear implantation. This study sought to address whether stapes surgery in this patient group provides a clinically significant audiological benefit.
To assess pre- and post-operative hearing outcomes of patients with advanced otosclerosis, and to determine what proportion of these patients required further surgery including cochlear implantation.
Between 2002 and 2015, 252 patients underwent primary stapes surgery at our institution. Twenty-eight ears in 25 patients were deemed to have advanced otosclerosis, as defined by pure audiometry thresholds over 80 dB. The patients’ records were analysed to determine audiological improvement following stapes surgery, and assess whether any further surgery was required.
The audiological outcome for most patients who underwent primary stapes surgery was good. A minority of patients (7 per cent) required revision surgery. Patients who underwent cochlear implantation after stapes surgery (10 per cent) also demonstrated a good audiological outcome.
Stapes surgery is a suitable treatment option for patients with advanced otosclerosis, and should be considered mandatory, before offering cochlear implantation, for those with a demonstrable conductive component to their hearing loss. A small group of patients get little benefit from surgery and subsequently a cochlear implant should be considered.
Bioarchaeological studies have found that, in general, the adoption of agriculture is associated with deteriorating oral health, most frequently manifested as an increase in the prevalence of dental caries. However, compared to other regions of the world, bioarchaeological studies focusing on prehistoric Europe have produced more variable results, with different populations experiencing deteriorations, improvements, and stasis in oral health. This study assesses the oral health of individuals of the Tripolye culture buried in Verteba Cave, Ukraine, within the context of the transition to agriculture in Eastern Europe. We compare the rates of dental caries between Tripolye farmers with earlier hunter-fisher-gatherers from Ukraine. The Tripolye were found to have carious lesions on 9.5 per cent of teeth, while the hunter-fisher-gatherers were found to be universally free of carious lesions. A Fisher's exact test demonstrates that this difference is statistically significant, supporting the model that the transition to agriculture was detrimental to oral health in prehistoric Ukraine. This could be related to the manner in which grain was processed by the Tripolye and the needs of their relatively population-dense society.
Blazar OJ 287 is one of the best observed extragalactic objects. It's historical light curve goes back to 1890′s. Based on the historical behaviour Sillanpää et al. (1988) showed that OJ 287 displays large periodic outbursts, with a period of 11.7 years. We have monitored OJ 287 intensively for two years, during the OJ-94 project. This project was created for monitoring OJ 287 during its predicted new outburst in 1994. In the data archive we have over 7000 observations on OJ 287, in the radio, infrared and optical bands. This data archive contains the best ever obtained light curves for any extragalactic object. The optical light curve shows continuous variability down to time scales of tens of minutes. The variability observed in OJ 287 can be broken down to (at least) four different categories:
This paper addresses the problem of designing low-order and linear robust feedback controllers that provide a priori guarantees with respect to stability and performance when applied to a fluid flow. This is challenging, since whilst many flows are governed by a set of nonlinear, partial differential–algebraic equations (the Navier–Stokes equations), the majority of established control system design assumes models of much greater simplicity, in that they are: firstly, linear; secondly, described by ordinary differential equations (ODEs); and thirdly, finite-dimensional. With this in mind, we present a set of techniques that enables the disparity between such models and the underlying flow system to be quantified in a fashion that informs the subsequent design of feedback flow controllers, specifically those based on the
loop-shaping approach. Highlights include the application of a model refinement technique as a means of obtaining low-order models with an associated bound that quantifies the closed-loop degradation incurred by using such finite-dimensional approximations of the underlying flow. In addition, we demonstrate how the influence of the nonlinearity of the flow can be attenuated by a linear feedback controller that employs high loop gain over a select frequency range, and offer an explanation for this in terms of Landahl’s theory of sheared turbulence. To illustrate the application of these techniques, an
loop-shaping controller is designed and applied to the problem of reducing perturbation wall shear stress in plane channel flow. Direct numerical simulation (DNS) results demonstrate robust attenuation of the perturbation shear stresses across a wide range of Reynolds numbers with a single linear controller.
We studied the association, and its direction, between the introduction of solids and weight-for-height (WFH) change between birth and 45 months. Pregnant women were asked to participate in a birth cohort during their first antenatal visit. Data from 3184 children were used. The timing of the introduction of solids was reported by the mother from a questionnaire at 12 months postpartum, and categorised into very early (0–3 months), early (3–6 months) and timely (after 6 months) introduction of solids. Anthropometric data were collected during standardised child health centre visits. WFH was converted into a z-score. Repeated-measurements analyses with splines positioned according to the moments of solid introduction were used to obtain estimates for WFH change before and after the introduction of solids. Analyses were adjusted for educational level, ethnicity, smoking during pregnancy, mother's BMI, breast-feeding, history of food allergy and infant's hospital admission. Before solids were introduced, weight gain was higher in children introduced to solids early (z= 0·65, 95 % CI 0·34, 0·95) than in children introduced to solids very early (z= 0·02, 95 % CI − 0·03, 0·08) and timely (z= − 0·04, 95 % CI − 0·05, − 0·03). Shortly after the introduction of solids, children introduced to solids very early and early showed a relative decrease in WFH. WFH change did not differ between the solid introduction groups after 12 months, and at that time, weight change was as expected (i.e. z= 0). We therefore conclude that differences in WFH in childhood are not the result of early introduction to solids.
Background: Depression in informal caregivers of persons with dementia is a major, costly and growing problem. However, it is not yet clear which caregivers are at increased risk of developing depression. With this knowledge preventive strategies could focus on these groups to maximize health gain and minimize effort.
Methods: The onset of clinically relevant depression was measured with the Center for Epidemiologic Studies - Depression Scale in 725 caregivers who were not depressed at baseline and who were providing care for a relative with dementia. Caregivers were followed over 18 months. The indices calculated to identify the most important risk indicators were: odds ratio, attributable fraction, exposure rate and number needing to be treated.
Results: The following significant indicators of depression onset were identified: increased initial depressive symptoms, poor self-rated health status and white or Hispanic race/ethnicity. The incidence of depression would decrease by 72.3% (attributive fraction) if these risk indicators together are targeted by a completely effective intervention. Race/ethnicity was not a significant predictor if caregivers of patients who died or were institutionalized were left out of the analyses.
Conclusion: Detection of only a few characteristics makes it possible to identify high-risk groups in an efficient way. Focusing on these easy-to-assess characteristics might contribute to a cost-effective prevention of depression in caregivers.
This paper reports the microstructure and physical properties of ferroelectric capacitors formed from SrBi2Ta2O9(SBT) layers on Si with various buffer layers including jet-vapor deposited silicon nitride, zirconium oxide, hafnium oxide and thermally grown silicon oxide. Results from cross-sectional transmission electron microscopy (X-TEM), energy dispersive spectroscopy (EDS), X-Ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and non-contact atomic force microscopy (nc-AFM) data coupled with capacitance-voltage (C-V) and current- voltage (I-V) data indicate that both the microstructure and physical properties of SBT films deposited on silicon are dependent on the buffer layer material employed.
We have performed total energy density functional theory calculations to investigate the sliding process at the ∑ = 5 (001) twist grain boundary in germanium. The accurate quantum mechanical description of the interatomic bonding provides valuable insights into the mechanisms of bond breaking and remaking that occur during the sliding.
In this paper we show how total energy calculations can be used to describe finite
temperature and strain rate effects in this grain boundary.
We are using total energy pseudopotential calculations to carry out an extensive investigation into grain boundary sliding in a number of different systems, in order to understand, at microscopic level, the fundamental mechanisms responsible for this process.
In this paper we present results for the sliding process at the ∑ = 5(001) twist grain boundary in germanium, chosen as a typical covalently bonded material, and contrast them with preliminary results obtained for the ∑ = 5 (001) twist grain boundary in aluminium, a typical metal.
Breast-feeding has been suggested to be associated with lower risks of obesity in older children and adults. We assessed whether the duration and exclusiveness of breast-feeding are associated with early postnatal growth rates and the risks of overweight and obesity in preschool children. The present study was embedded in a population-based prospective cohort study from early fetal life onwards, among 5047 children and their mothers in The Netherlands. Compared with children who were breast-fed, those who were never breast-fed had a lower weight at birth (difference 134 (95 % CI − 190, − 77) g). No associations between breast-feeding duration and exclusivity with growth rates before the age of 3 months were observed. Shorter breast-feeding duration was associated with an increased gain in age- and sex-adjusted standard deviation scores for length, weight and BMI (P for trend < 0·05) between 3 and 6 months of age. Similar tendencies were observed for the associations of breast-feeding exclusivity with change in length, weight and BMI. Breast-feeding duration and exclusivity were not consistently associated with the risks of overweight and obesity at the ages of 1, 2 and 3 years. In conclusion, shorter breast-feeding duration and exclusivity during the first 6 months tended to be associated with increased growth rates for length, weight and BMI between the age of 3 and 6 months but not with the risks of overweight and obesity until the age of 3 years.
Background: The aging society will bring an increase in the number of people with dementia living in the community. This will mean a greater demand on care and welfare services to deliver efficient and customized care, which requires a thorough understanding of subjective and objective care needs. This study aims to assess the needs of community-dwelling people with dementia as reported by themselves and by their informal carers. The study also aims to give insight into the service use and gaps between needs and the availability of services.
Methods: 236 community-dwelling people with dementia and 322 informal carers were interviewed separately. (Un)met needs were assessed using the Camberwell Assessment of Needs for the Elderly (CANE).
Results: Most unmet needs were experienced in the domains of memory, information, company, psychological distress and daytime activities. People with dementia reported fewer (unmet) needs than their carers. Type and severity of dementia, living situation and informal carer characteristics were related to the number of reported needs.
Conclusions: This study showed a large number of unmet needs in dementia. Reasons for unmet needs are lack of knowledge about the existing service offer, a threshold to using services and insufficient services offer. These results provide a good starting point for improving community care for people with dementia.
Background: Tailor-made care in dementia requires an individual needs assessment. The Camberwell Assessment of Need for the Elderly (CANE) was developed to assess needs of older people with mental disorders. In this study the validity and reliability of the Dutch version of the CANE were studied among community-dwelling persons with dementia and their informal carers.
Method: Interviews were carried out with 236 people with mild to severe dementia and 322 informal carers; 69 informal carers were interviewed twice. Construct and criterion validity and test-retest reliability of the CANE were studied using data for informal carers. Construct validity was also studied for CANE ratings of people with dementia.
Results: The construct validity of the CANE was good among people with dementia and informal carers. Criterion validity could be studied for 76.9% of the CANE items, and all significant correlations were convergent. Test-retest reliability of the CANE varied from poor to very good and was best on domains where needs were explicit and problems well defined.
Conclusions: Use of the Dutch version of the CANE among community-dwelling people with dementia and their carers is supported by the study results, with the study showing acceptable construct and criterion validity and test-retest reliability of the CANE.
Austrian veterinary (n=91), dairy (n=86), and human strains (n=48) of Staphylococcus aureus were tested for various phenotypic properties including clumping factor, egg-yolk reaction, production of thermonuclease and susceptibility to 14 antibiotics. In addition the expression of enterotoxins (A–E), and the presence of enterotoxin genes sea to sej and tst was determined. Significant differences in antimicrobial susceptibility were found with 84·6% of veterinary, 57·0% of dairy, and 20·8% of human strains susceptible to all antibiotics tested (P<0·0005). More human strains produced enterotoxins (41·7%) than veterinary (9·9%) and dairy strains (12·6%) while 40·7% and 38·5% of veterinary, 47·7% and 52·3% of dairy, and 77·1% and 87·5% of human strains were se- and tst-positive, respectively. AFLP analysis revealed nine clusters with over- or under-representation of strains with specific characteristics. Strains clustered according to origin (veterinary, dairy, and human) and/or presence of toxin genes and antimicrobial resistance.
Objectives: Major depression is common in elderly patients. Interpersonal psychotherapy (IPT) is a potentially effective treatment for depressed elderly patients. The objective of this study was to evaluate the cost-effectiveness of IPT delivered by mental health workers in primary care practices, for depressed patients 55 years of age and older identified by screening, in comparison with care as usual (CAU).
Methods: We conducted a full economic evaluation alongside a randomized controlled trial comparing IPT with CAU. Outcome measures were depressive symptoms, presence of major depression, and quality of life. Resource use was measured from a societal perspective over a 12-month period by cost diaries. Multiple imputation and bootstrapping were used to analyze the data.
Results: At 6 and 12 months, the differences in clinical outcomes between IPT and CAU were small and nonsignificant. Total costs at 12 months were €5,753 in the IPT group and €4,984 in the CAU group (mean difference, €769; 95 percent confidence interval, −2,459 – 3,433). Cost-effectiveness planes indicated that there was much uncertainty around the cost-effectiveness ratios.
Conclusions: Based on these results, provision of IPT in primary care to elderly depressed patients was not cost-effective in comparison to CAU. Future research should focus on improvement of patient selection and treatments that have more robust effects in the acute and maintenance phase of treatment.