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Assessing short channel effects (SCEs) is crucial in the high-frequency optimization of downscaled field-effect transistors (FETs) such as GaN high electron mobility transistors (HEMTs). Drain-induced barrier lowering (DIBL) is commonly used for quantifying the ability of the gate to modulate the drain-source current at high drain voltages. DIBL is traditionally extracted from the relative shift of the threshold voltage at different drain-source voltages. In this article, we propose a new method based on a drain current injection technique (DCIT) to assess DIBL. This method facilitates a direct measure of the threshold voltage over a wide range of drain-source voltages in a single measurement. The method is demonstrated and compared to the conventional method using AlGaN/GaN and InAlGaN HEMTs with a Fe-doped buffer and a C-doped AlGaN back-barrier, respectively. Furthermore, the impact of different gate lengths and GaN channel layer thicknesses is presented. The measurements are analyzed and discussed with supporting technology computer-aided design (TCAD) simulations. The proposed method facilitates a more general and detailed measurement of the DIBL for HEMTs.

ObjectiveThe aim was to test if targeting managers with an educational intervention reduces absence among pregnant employees.MethodsThe study was a non-blinded cluster randomised trial conducted in hospitals and daycare institutions from two administrative Danish Regions and two Danish municipalities. Clusters (work units) were assigned randomly and non-blinded to either (1) intervention, where all managers were invited to participate in a 3-hour seminar addressing needs and options for adjustment of work in pregnancy, or (2) control, with practice as usual. The primary outcome based on payroll data was long-term pregnancy-related absence, defined as ≥12.5% cumulated absence during pregnancy weeks 1–32. Intention-to-treat analysis was applied using mixed logistic regression.ResultsNinety work units were included (56 hospital departments and 34 daycare units) with 451 pregnant employees in the intervention group and 464 in the control group. Work units had on average 11 pregnant employees with no difference between the groups. 103 of the 216 invited managers (48%) participated in a the 3-hour seminar. In the intervention group, 154 (34%) had long-term pregnancy-related absence during pregnancy weeks 1–32 vs 166 (36%) in the control group. Relative odds of having long-term pregnancy-related absence, when being in the intervention group, was 1.06 (95% CI 0.71 to 1.58), with an interclass correlation coefficient of 0.07.ConclusionAn educational intervention targeting managers did not reduce pregnancy-related absence among pregnant employees.Trial registration numberNCT03002987.

The study presented here was made in collaboration with a medical device manufacturer. Normally, the device manufacturer uses verbal self-reporting protocols, interviews and observations in their formative usability tests during product development. The objective of our study was to investigate whether the use of eye-tracking technology can contribute to the data collection and bring new data and knowledge into the product development. The use of eye-tracking provided five unique insights and findings. Although the evaluated significance of them varied, a couple of findings stands out as important, indicating that the use of eye-trackers can indeed contribute positively to the results obtained from a usability test based on traditional ethnographic methods. It should be noted that use of eye-tracking requires additional time, resources and technical skills including optimal light conditions. However, with the promising perspectives in mind, eye-tracking is recommendable as an additional tool for usability studies.

AbstractRespondent-driven sampling (RDS) is frequently used when sampling from hidden populations. In RDS, sampled individuals pass on participation coupons to at most cof their acquaintances in the community (c= 3 being a common choice). If these individuals choose to participate, they in turn pass coupons on to their acquaintances, and so on. The process of recruiting is shown to behave like a new Reed–Frost-type network epidemic, in which 'becoming infected' corresponds to study participation. We calculate R0, the probability of a major 'outbreak', and the relative size of a major outbreak for c< 8 in the limit of infinite population size and compare to the standard Reed–Frost epidemic. Our results indicate that cshould often be chosen larger than in current practice.

Respondent-driven sampling (RDS) is often used to estimate population properties (e.g., sexual risk behavior) in hard-to-reach populations. In RDS, already sampled individuals recruit population members to the sample from their social contacts in an efficient snowball-like sampling procedure. By assuming a Markov model for the recruitment of individuals, asymptotically unbiased estimates of population characteristics can be obtained. Current RDS estimation methodology assumes that the social network is undirected, that is, all edges are reciprocal. However, empirical social networks in general also include a substantial number of nonreciprocal edges. In this article, we develop an estimation method for RDS in populations connected by social networks that include reciprocal and nonreciprocal edges. We derive estimators of the selection probabilities of individuals as a function of the number of outgoing edges of sampled individuals. The proposed estimators are evaluated on artificial and empirical networks and are shown to generally perform better than existing estimators. This is the case in particular when the fraction of directed edges in the network is large.

The assessment of extra-, intracellular and total body water (ECW, ICW, TBW) is important in many clinical situations. Bioimpedance spectroscopy (BIS) has advantages over dilution methods in terms of usability and reproducibility, but a careful analysis reveals systematic deviations in extremes of body composition and morbid states. Recent publications stress the need to set up and validate BIS equations in a wide variety of healthy subjects and patients with fluid imbalance. This paper presents two new equations for determination of ECW and ICW (referred to as body composition spectroscopy, BCS) based on Hanai mixture theory but corrected for body mass index (BMI). The equations were set up by means of cross validation using data of 152 subjects (120 healthy subjects, 32 dialysis patients) from three different centers. Validation was performed against bromide/deuterium dilution (NaBr, D2O) for ECW/TBW and total body potassium (TBK) for ICW. Agreement between BCS and the references (all subjects) was ?0.4 ± 1.4 L (mean ± SD) for ECW, 0.2 ± 2.0 L for ICW and ?0.2 ± 2.3 L for TBW. The ECW agreement between three independent reference methods (NaBr versus D2O?TBK) was ?0.1 ± 1.8 L for 74 subjects from two centers. Comparing the new BCS equations with the standard Hanai approach revealed an improvement in SEE for ICW and TBW by 0.6 L (24%) for all subjects, and by 1.2 L (48%) for 24 subjects with extreme BMIs (<20 and >30). BCS may be an appropriate method for body fluid volume determination over a wide range of body compositions in different states of health and disease.

We have studied the effect of acute trazodone (3–20 mg kg−1) and quipazine (1–3 mg kg−1) treatment on the apomorphine-induced (1 mg kg−1, once daily over 2 weeks) aggressive behaviour in male Wistar rats. All doses of trazodone and quipazine tested attenuated the aggressiveness as evidenced by the abolished intensity of aggressive behaviour and increased time of latency before the first attack. The acute trazodone (3–10 mg kg−1) or quipazine (1–3 mg kg−1) treatment had no or only a minor effect on rat behaviour in the elevated plus-maze, open field, and forced swimming test. Concomitant apomorphine (1 mg kg−1) plus trazodone (3 mg kg−1), but not apomorphine (1 mg kg−1) plus quipazine (1 mg kg−1), treatment slowed the development of aggressive behaviour. Repeated apomorphine treatment moderately reduced the dopamine post mortemand increased the DOPAC and HVA contents in striatum. Other monoamines or their metabolites were unchanged. Neither trazodone and quipazine treatment nor forced swimming stress induced any changes in the monoamine contents. In conclusion, our results indicate that acute trazodone and quipazine treatment attenuates the apomorphine-induced aggressive behaviour in male rats, but this phenomenon cannot be implicated in the changes in emotional and motivational behaviour, or in changes of monoamine content post mortem.

Multinuclear and multidimensional NMR spectroscopy have shown that lithium (S)‐N‐isopropyl‐O‐methyl‐valinol (1‐[6Li]) exists in a mixed 2:1 complex with nBu[6Li], (1‐[6Li])2/nBu[6Li], in non‐coordinating solvents such as hexane or toluene. A 6Li,1H‐HOESY NMR spectrum indicates that the complex is a cyclic trimer with a large distance between the di‐coordinated lithium and the carbanion of nBu[6Li]. Such arrangements are present in the solid state as previously reported by Williard and Sun. The exchange of lithium atoms within the trimer is slow at −33 °C. The exchange barrier (ΔG≠) was determined to be 14.7 kcal mol−1from quantitative 6Li,6Li‐EXSY spectra. Addition of diethyl ether results in the formation of mixed dimers of (1‐[6Li])/nBu[6Li], tetramers of nBu[6Li], and homodimers (1‐[6Li])2. The apparent equilibrium constant of the mixed dimer was determined from the 6Li NMR integrals as K=7.

Birgit Sawyer, Peter Sawyer and Ian Wood (eds), The Christianization of Scandinavia, Report of a Symposium held at Kungalv, Sweden, 4-9 August 1985 (Alingsås, 1987).Claus Bjørn, Troels Dahlerup, S. P. Jensen and Erik H. Pedersen (eds), Det danske landbrugs historie (A history of Danish agriculture) I-II (Odense: Landbohistorisk Selskab 1988). 417+394 pp., ill. ISBN 87-7526-082-4. (All four volumes.) D.kr. 128.

Two hundred wood samples have been examined from the Viking settlement at Argisbrekka on Eysturoydated to AD 770-1015. They fall into three categories:-1. local wood: Juniperus. Betula pubescens Ehrh., Corylus, Salix and heathland dwarf shrubs; 2. driftwood: Picea, Larix and Pinus section strobus; and 3. imported wood: Quercus, Pinus section sylvestris, Alnus and Fraxinus. The local tree vegetation was over-exploited and Betula became extinct in the course of the Viking Age. Driftwood, mainly of Siberian origin, seems to be the most important tree resource and was used for houses and utensils. Imported wood probably mostly comprised ships and finished products made in Scandinavia. The detection of tree Betula growth between 2,460 BC and AD 770 is a new contribution to the vegetational history of the Faroe Islands.

A project is described concerning the examination of wood from two settlements on Eysturoy. Argisbrekka is a seasonally occupied inland settlement radiocarbon-dated to the 9th-11th centuries, while Toftanes is a year-round coastal settlement from the 9th-10th centuries. Preliminary investigations of wood from houses and refuse layers at Argisbrekka demonstrate the utilization of three resources: (a) local vegetation of Juniperus, tree Betula and heathland dwarf shrubs, (b) driftwood Picea and Larix, (c) imported wood Pinus and Quercus. The impact of man and husbandry on the vegetation probably resulted in the extinction of tree Betula and the almost total disappearance of Juniperus.

If the increase in trienoic acids may be taken as chemical evidence of EFA deficiency, the results of this preliminary investigation suggest that prolonged ingestion of high levels of saturated fat may lead to a relative deficiency of essential fatty acids.