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During each Heinrich stadial (HS), temperatures in southern Europe typically dropped several degrees during several hundred to few thousand years. We have developed a one-dimensional thermal conduction model that transfers the typical surface temperature anomaly of a HS to a series of hypothetical underlying caves. The results show that with increasing depth, the thermal anomaly is attenuated, the lag time increases, and the signal structure experiences larger modifications. The model suggests that in most cases, it is not acceptable to assume a synchronous thermal variability and similar average temperature values between the surface atmosphere and the cave interior at millennial timescales. We also simulated the thermal impact of the modeled HS on speleothem δ18O records. The outputs of most model scenarios suggest that temperature changes associated with the HS produce δ18O anomalies capable of contributing significantly or even decisively to the speleothem isotope variability. Therefore, despite controls other than temperature often being considered more important when interpreting Pleistocene speleothem δ18O records in temperate climates, this research suggests that temperature is expected to be one of the major controls of δ18O values in most cave sites outside the tropics and should be included as a significant parameter affecting Pleistocene speleothem δ18O records.
This paper presents a novel GaN-based digital outphasing power amplifier (PA) for the 800 MHz range. The PA reaches a maximum output power of 5.8 W at 30 V final-stage (FS) drain supply voltage. A novel output combiner circuit is used and efficiency is improved by resonant commutation of the FSs and optimized driver circuits for the two GaN push-pull FSs. 3D electromagnetic simulation of output network has been conducted to extract an equivalent circuit model and to access full information in terms of functionality and broadband impedance characteristics for optimized outphasing operation in the final design. Measured total efficiencies (ηtot) of 59 and 25% at 0 and 10 dB power back-off are achieved, respectively, fitting the simulation quite well. The proposed digital outphasing module is a promising candidate for fully digitized base-station architectures in future wireless communications.
Research with psychiatric patients raises frequently discussed, ethical questions, one of which is: Can psychiatric patients give consent to participation in research at all? To answer this and similar questions adequately, it is - according to our thesis - necessary to analyze first, which theoretical assumptions are made in established practice.
To solve the question after the possibility of consent, compatible understandings of ‘disease’, ‘illness’ and ‘autonomy’ are crucial, but there is no consensual use of these terms in philosophy. Therefore we first are going to explain different concepts of ‘autonomy’ and ‘disease’. Subsequent to this we will test how the different conceptualizations of ‘autonomy’ and ‘disease’ can be related to each other and how the reasonable combinations shape possible answers to the opening question. It will become apparent that an adequate analysis of ‘autonomy’ and ‘disease’ raises ethical dilemma in psychiatry, for which we shall suggest possible solutions.
Adult patients with ADHD suffer from marriage problems and increased divorce rates significantly more often. There are, however, only a few studies which analyse romantic attachment to a partner or romantic relationships among patients with ADHD in view of attachment theory.
The aim of the present study is to research if ADHD patients show a diminished quality of romantic relationships in comparison to a matched sample of healthy controls. Furthermore, correlations between ADHD specific characteristics and particular variables of partnership perception and psychosomatic discomfort were analysed within the ADHD subgroup.
We recruited 39 patients with ADHD and compared them with a matched sample of healthy controls. Self-estimation measures were used to examine the quality of attachment, dimensions of attachment, love styles, psychosomatic discomfort and ADHD specific symptoms.
In comparison to the control sample, adult ADHD patients show a significantly reduced quality of relationships. ADHD patients rank themselves as more scared of attachment and showing more avoidance of interpersonal relationships in general as well as romantic relationships. They also feel less romantic love. ADHD specific characteristics correlate moderately with the attachment dimensions “Fear” and “Avoidance”, the love style “Mania” and psychosomatic discomfort.
This study lends further support to the assumption that adult patients with ADHD show an impaired quality of attachment, increased fear and avoidance of relationships as well as less romantic love. The results strongly underline the necessity to account for individual attachment styles in psychotherapy of ADHD.
Studies have shown that mental health risks related to military deployment depend on specific risk factors. Especially stressful experiences (SE) and lack of social support (SS) have been associated with deployment-related increases in mental disorders. Less is known about difficulties in emotion regulation (DER) in this context despite their well-known importance for the development and maintenance of mental disorders. To date, the number of prospective studies investigating the role of these potential risk factors for deployment-related psychopathology is limited.
To investigate risk factors for deployment-related increases in symptoms of common mental disorders.
To investigate associations between SE, SS and DER, and deployment-related increases in PTSD, major depression (MD) and alcohol use disorder (AUD) symptoms.
358 male soldiers were assessed before and 12 months following deployment using standardized diagnostic interviews (CIDI) and embedded questionnaires. Outcome measures were the number of PTSD, MD and AUD symptoms reported for the preceding 12 months at follow-up. Analyses were adjusted for baseline symptoms.
SE (incidence risk ratio (IRR)):1.06, p>0.001), SS (IRR:0.98, p=0.034) and DER (IRR:1.04, p=0.009) independently predicted increases in PTSD symptoms. SE (IRR:1.04, p=0.004) and SS (IRR:0.98, p=0.022) also predicted increases in MD symptoms. Increase in AUD symptoms was not predicted by SE, SS or DER, but by increase in PTSD symptoms (IRR:1.02, p=0.029).
Findings support the role of SE, SS and DER as risk factors for deployment-related disorders, particularly for PTSD symptoms. This knowledge might help to identify high-risk individuals and to develop targeted interventions.
To evaluate whole-genome sequencing (WGS) as a molecular typing tool for MRSA outbreak investigation.
Investigation of MRSA colonization/infection in a neonatal intensive care unit (NICU) over 3 years (2014–2017).
Single-center level IV NICU.
NICU infants and healthcare workers (HCWs).
Infants were screened for MRSA using a swab of the anterior nares, axilla, and groin, initially by targeted (ring) screening, and later by universal weekly screening. Clinical cultures were collected as indicated. HCWs were screened once using swabs of the anterior nares. MRSA isolates were typed using WGS with core-genome multilocus sequence typing (cgMLST) analysis and by pulsed-field gel electrophoresis (PFGE). Colonized and infected infants and HCWs were decolonized. Control strategies included reinforcement of hand hygiene, use of contact precautions, cohorting, enhanced environmental cleaning, and remodeling of the NICU.
We identified 64 MRSA-positive infants: 53 (83%) by screening and 11 (17%) by clinical cultures. Of 85 screened HCWs, 5 (6%) were MRSA positive. WGS of MRSA isolates identified 2 large clusters (WGS groups 1 and 2), 1 small cluster (WGS group 3), and 8 unrelated isolates. PFGE failed to distinguish WGS group 2 and 3 isolates. WGS groups 1 and 2 were codistributed over time. HCW MRSA isolates were primarily in WGS group 1. New infant MRSA cases declined after implementation of the control interventions.
We identified 2 contemporaneous MRSA outbreaks alongside sporadic cases in a NICU. WGS was used to determine strain relatedness at a higher resolution than PFGE and was useful in guiding efforts to control MRSA transmission.
Aberrant reward mechanisms with regard to slim body shapes are discussed in patients with anorexia nervosa (AN). The aim of the present study was to examine of cue reactivity toward body shapes in AN via the late positive potential (LPP), an event-related electroencephalography (EEG) component. By including adolescents and adults, aspects of development and chronification could be studied (2 × 2 design).
Thirty-two female AN patients (19 adolescents and 13 adults) and 37 control participants (16 adolescents and 21 adults) were included. Standardized photographic stimuli showing women's bodies in underwear from five body mass index (BMI) categories (extremely underweight to extremely overweight) were presented. During picture evaluation, EEG activity was recorded (10–20 system). The LPP was measured in two time windows characterized by different topographies (450–700 ms: posterior; 1000–1300 ms: central).
Regarding the posterior component, LPP amplitudes were clearly reduced in adult but not in adolescent patients; for both time windows the LPP showed differential patterns over BMI categories for patients and controls. Regarding the central component, a highly significant linear decrease from extremely underweight to extremely overweight body shapes was revealed in patients and no significant modulation in control participants.
Adolescent and adult patients show increased sustained attention toward extremely underweight bodies. In chronically ill patients, this bias appears to be accompanied by generally reduced automatic attention. The LPP findings provide a differentiated picture of aberrant cue reactivity which could be interpreted as motivated attention toward body shapes in AN.
Post-traumatic stress disorder (PTSD) is often associated with attention allocation and emotional regulation difficulties, but the brain dynamics underlying these deficits are unknown. The emotional Stroop task (EST) is an ideal means to monitor these difficulties, because participants are asked to attend to non-emotional aspects of the stimuli. In this study, we used magnetoencephalography (MEG) and the EST to monitor attention allocation and emotional regulation during the processing of emotionally charged stimuli in combat veterans with and without PTSD.
A total of 31 veterans with PTSD and 20 without PTSD performed the EST during MEG. Three categories of stimuli were used, including combat-related, generally threatening and neutral words. MEG data were imaged in the time-frequency domain and the network dynamics were probed for differences in processing threatening and non-threatening words.
Behaviorally, veterans with PTSD were significantly slower in responding to combat-related relative to neutral and generally threatening words. Veterans without PTSD exhibited no significant differences in responding to the three different word types. Neurophysiologically, we found a significant three-way interaction between group, word type and time period across multiple brain regions. Follow-up testing indicated stronger theta-frequency (4–8 Hz) responses in the right ventral prefrontal (0.4–0.8 s) and superior temporal cortices (0.6–0.8 s) of veterans without PTSD compared with those with PTSD during the processing of combat-related words.
Our data indicated that veterans with PTSD exhibited deficits in attention allocation and emotional regulation when processing trauma cues, while those without PTSD were able to regulate emotion by directing attention away from threat.
This commentary focuses on two related, open questions in Hulleman & Olivers' (H&O's) proposal: (1) the nature of the parallel attentive process that determines target presence within, and thus presumably the size of, the functional visual field, and (2) how the pre-attentive guidance mechanism must be conceived to also account for search performance in tasks that afford no reliable target-based guidance.
We show that our item-based model, competitive guided search, accounts for the empirical patterns that Hulleman & Olivers (H&O) invoke against item-based models, and we highlight recently reported diagnostic data that challenge their approach. We advise against “forsaking the item” unless and until a full fixation-based model is shown to be superior to extant item-based models.
Leptin is thought to act as an important mediator in stress reactions. To date, no study has examined the association between psychological stress and leptin levels in children. This study aimed to assess the association between emotional symptoms and peer problems and serum leptin levels in children aged 10 years of the two population-based GINI-plus and LISA-plus birth cohorts.
Cross-sectional data from 2827 children aged 10 years were assessed with regard to leptin concentrations in serum and behavioral problems using the parent-reported Strengths and Difficulties Questionnaire (SDQ). Linear regression modeling was applied to determine the likelihood of elevated leptin levels in children with emotional symptoms and peer problems, controlling for socio-economic status (SES), body mass index (BMI), fasting serum leptin levels, pubertal development and sex hormones.
We found that increases in emotional symptoms (exp βadj = 1.03, s.e. = 0.02, p < 0.04) and peer problems (exp βadj = 1.05, s.e. = 0.01, p = 0.0001) were significantly associated with higher serum leptin levels controlled for BMI and sociodemographic factors. Similar results were found when the fasting serum leptin sample was examined (exp βadj = 1.08, s.e. = 0.04, p = 0.0294). Gender-stratified analyses showed a significant relationship between serum leptin and peer problems in girls (exp βadj = 1.05, s.e. = 0.02, p = 0.03), and a borderline significant association in boys (exp βadj = 1.04, s.e. = 0.02, p = 0.05).
Children with peer problems have higher stress and eat more, acquire a higher body fat mass and thus, through increased leptin resistance, exhibit higher leptin levels.
Experimental observations of supersonically flowing dusty plasmas and their interaction with an electrically biased circular cylinder are presented. Two methods for producing flowing dusty plasmas are described. The dusty plasma is produced in a DC anode glow discharge plasma. In Configuration I, a secondary dust cloud, initially formed near a biased grid, flowed away from the grid at supersonic speeds when the grid voltage was suddenly changed. In Configuration II, a pencil-like dust beam was produced using a nozzle-like (converging-diverging) electrostatic potential structure. Using Configuration I, the streaming dust encountered a biased cylinder (wire) whose axis was oriented transverse to the dust flow. The flowing dust particles were repelled by the electrostatic field of the negatively charged cylinder, and a dust void was formed around the cylinder. A detached electrohydrodynamic bow shock, akin to the Earth's magnetohydrodynamic bow shock, was formed on the upstream side of the cylinder, while an extended teardrop-shaped wake region was formed on the downstream side. Video imaging of the dust stream allowed for observations of the structure and evolution of the bow shock. Configuration II was used to produce a narrow beam of dust particles and observe how the beam was deflected around the biased cylinder. Three multimedia files (movies) of the observed phenomena are provided in the online Supplementary material.
The objective of this study was to determine the effects of varying forage particle length on chewing activity, sorting behavior, rumen pH and rumen fill in late lactation and dry dairy cattle, fed rations with similar physically effective NDF but different mean particle length. Treatments consisted of three diets differing only in geometric mean length of forage: hay (5.40, 8.96 and 77.90 mm, for short (S), medium (M) and long (L) diets, respectively) for Experiment 1 (E1), and straw (10.16, 24.68 and 80.37 mm) for S, M and L diets, respectively, for Experiment 2 (E2). Hay or straw comprised the sole source of forage (50% and 75% of ration dry matter (DM) for E1 and E2, respectively). Both experiments used three rumen cannulated Holstein dairy cows, in late lactation for E1 and dry in E2, with 3 × 3 Latin square designs with 14 day periods. In E1, DM intake (DMI; 18.3 ± 2.1 kg/day; mean ± s.e.), pH (6.4 ± 0.1), time spent eating (280 ± 22.5 min/day), time spent ruminating (487 ± 17 min/day), and total time spent chewing (767 ± 34 min/day) were not different, whereas eating minutes per kilogram of DMI and NDF intake (NDFI) tended to increase linearly as forage length increased. Rumen digesta volume (l; 113.3 S, 117.8 M and 114.4 L ± 17.1) had a quadratic response, and rumen digesta weight tended to respond quadratically; however, differences were numerically small. In E2, DMI (8.3 ± 1.3 kg/day), pH (6.7 ± 0.1), time spent eating (236 ± 23.5 min/day), time spent ruminating (468 ± 45.2 min/day), total time spent chewing (704 ± 67.7 min/day) and minutes per kilogram NDFI were not different, whereas minutes per kilogram of DMI had a trend for a quadratic effect. Rumen digesta volume (111 ± 18.8 l) and weight (103 ± 17.4 kg) were not different. In both experiments, cows sorted against longer particles as determined by a particle length selection index; this behavior increased linearly as particle length increased. Greater forage particle length increased sorting behavior, but had no effect on rumen fermentation or chewing behavior.