184 research outputs found
Axially excited spatial double pendulum nonlinear dynamics.
Analysis of a 3D spatial double physical pendulum system, coupled by two
universal joints is performed. External excitation of the mechanism is realized
by axial periodic rotations of the first joint of the pendulum. System of ODEs
is solved numerically and obtained data are analyzed by a standard approach,
including time series, phase plots and Poincaré sections. Additionally, FFT (Fast
Fourier Transform and the wavelet transformation algorithms have been applied.
Various wavelet basic functions have been compared to find the best fit, e.g. Morlet,
Mexican Hat and Gabor wavelets. The so far obtained results allowed for detection
of a number of non-linear effects, including chaos, quasi-periodic and periodic
dynamics, as well the numerous and different bifurcations. Scenarios of transition
from regular to chaotic dynamics have been also illustrated and studied
Sweeping by Sessile Drop Coalescence
During coalescence of liquid drops contacting a solid, the liquid sweeps
wetted and solid-projected areas. The extent of sweeping dictates the
performance of devices such as self-cleaning surfaces, anti-frost coatings,
water harvesters, and dropwise condensers. For these applications, weakly- and
non-wetting solid substrates are preferred as they enhance drop dynamical
behavior. Accordingly, our coalescence studies here are restricted to drops
with contact angle 90{\deg} 180{\deg}. Binary sessile drop
coalescence is the focus, with volume of fluid simulations employed as the
primary tool. The simulations, which incorporate a Kistler dynamic contact
angle model, are first validated against three different experimental substrate
systems and then used to study the influence of solid wettability on sweeping
by modifying . With increasing up to 150{\deg}, wetted
and projected swept areas both increase as drop center of mass heightens. For
150{\deg}, coalescence-induced drop jumping occurs owing to
the decreasing wettability of the substrate and a focusing of liquid momentum
due to the symmetry-breaking solid. In this regime, projected swept area
continues to increase with while wetted swept area reaches a maximum
and then decreases. The sweeping results are interpreted using the mechanical
energy balance from hydrodynamic theory and also compared to free drop
coalescence.Comment: 17 pages, 10 figures, 3 tables, to be published in Eur. Phys. J.
Special Topics: Challenges in Nanoscale Physics of Wetting Phenomen
Prädiktoren und Behandlungsverläufe bei Anorexia nervosa: Evaluation des Phasenessprogrammes der Station 2 der Klinik und Poliklinik für Psychotherapie und Psychosomatik
Laut S3-Leitlinie zur „Diagnostik und Therapie der Essstörungen“ (AWMF, 2019) ist bei PatientInnen mit Anorexia nervosa (AN) eine zeitnahe Aufnahme einer Therapie wesentlich. Dabei stehen die Normalisierung des Essverhaltens sowie des Gewichtes im Vordergrund. Dennoch ist die Heilung von AN meist mit vielen Therapien und Krankenhausaufenthalten verbunden, nicht zuletzt aufgrund der recht hohen Therapieabbruchrate. Kliniker und Forscher sind daher bemüht Prädiktoren für den Therapieverlauf von AN-PatientInnen zu finden, um den Verlauf bei RisikopatientInnen besser steuern und gestalten zu können. Die Ableitung allgemeingültiger Regeln ist aufgrund der meist geringen Stichprobengröße sowie variierender methodischer Vorgehensweisen bislang jedoch noch nicht möglich gewesen. Die vorliegende Arbeit überprüft, inwiefern sich schon diskutierte Prädiktoren im Behandlungsverlauf der AN identifizieren und zur Erstellung eines Prädiktorenmodelles für den Therapieerfolg (BMI≥19kg/m2) bzw. Therapieabbruch eignen. Ein weiteres Ziel der vorliegenden retrospektiven-naturalistischen Studie ist die Evaluation einer stationären psychosomatischen Behandlung von Patientinnen mit Anorexia nervosa in der Klinik für Psychotherapie und Psychosomatik (PSO) des Universitätsklinikums Carl Gustav Carus in Dresden. Dazu wurden die Daten von N = 75 weiblichen anorektischen Patientinnen einbezogen, die im Zeitraum von 2015-2019 länger als zwei Wochen an dem kognitiv-verhaltenstherapeutischen Phasenessprogramm der PSO teilgenommen haben. Es zeigte sich, dass das Phasenessprogramm insgesamt eine hohe Effektstärke bzgl. der Gewichtszunahme aufweist und damit als wirksam eingestuft werden kann. Relativiert wird dieser Effekt durch die vielen vorzeitigen Therapiebeendigungen, wodurch insgesamt bei weniger als der Hälfte der Patientinnen eine Gewichtsnormalisierung realisiert werden konnte. Für den Therapieerfolg konnte im Rahmen dessen ein Prädiktorenmodell erstellt werden, welches eine höhere Therapieerfolgschance je BMI-Punkt bei Aufnahme, sowie beim Fehlen einer komorbiden affektiven Störung vorhersagt. Für einen Therapieabbruch konnte lediglich der BMI bei Aufnahme als Prädiktor identifiziert werden. Das Ableiten eines allgemeingültigen Prädiktorenmodells für den Therapieverlauf bei AN scheint daher nur begrenzt möglich. Es scheint vielversprechender zu sein, individuelle Indikatoren zu suchen, um frühzeitig auf RisikopatientInnen eingehen zu können und gemeinsam adäquate Therapieziele zu entwickeln, um somit langfristig die Motivation sowie die Selbstwirksamkeit der Patientinnen zu stärken und aufrecht zu erhalten.According to the S3-guideline on 'Diagnosis and Therapy of Eating Disorders' (AWMF, 2019), it is essential for patients with anorexia nervosa (AN) to start therapy as soon as possible. The normalization of eating behavior and weight is of primary importance. Nevertheless, the cure of AN is usually associated with many therapies and hospital stays, not least because of the rather high therapy discontinuation rate. Researchers are therefore trying to find predictors for the course of therapy of AN patients in order to be more able to control and shape the course of therapy, especially in high risk patients. However, the derivation of generally valid rules has not yet been possible due to the usually small sample size and varying methodological procedures. The present study examines the extent to which predictors, that have already been discussed (elsewhere), can be identified during treatment and are suitable for creating a predictor model for the success of therapy (BMI≥19kg/m2) or for discontinuation (drop out) of therapy. A further aim of the present retrospective-naturalistic study is the evaluation of an inpatient psychosomatic treatment for patients with anorexia nervosa in the Clinic for Psychotherapy and Psychosomatics (PSO) of the University Hospital Carl Gustav Carus in Dresden. Data from N = 75 female anorexic patients who participated in the cognitive-behavioral “phase- program” of the PSO for more than two weeks in the period 2015-2019 were included. It was shown that the “phase-program” has a high overall effect strength with regard to weight gain and can therefore be classified as effective. This effect is put into perspective by the many premature terminations of therapy, whereby a normalization of weight was achieved in less than half of the patients. For the success of the therapy, a predictor model was developed which predicts a higher chance of success per BMI point on admission and the absence of a comorbid mood disorder. For a therapy discontinuation, only the BMI at admission could be identified as predictor. Therefore, the derivation of a generally valid predictor model for the course of therapy in AN seems to be possible only to a limited extent. It seems to make much more sense to look for individual indicators in order to be able to respond to at-risk patients at an early stage and to jointly develop adequate therapy goals in order to strengthen and maintain the motivation and self-efficacy of patients in the long run
Mathematical model of pennate muscle.
The purpose of this study is to create a new mathematical model of pennate striated skeletal muscle. This new model describes behaviour of isolated flat pennate muscle in two dimensions (2D) by taking into account that rheological properties of muscle fibres depend on their planar arrangement. A new mathematical model is
implemented in two types: 1) numerical model of unipennate muscle (unipennate model); 2) numerical model of bipennate muscle (bipennate model). Applying similar boundary conditions and similar load, proposed numerical models had been tested. Obtained results were compared with results of numerical researches by applying a
Hill-Zajac muscle model (this is a Hill type muscle model, in which the angle of pennation is taken into consideration) and a fusiform muscle model (a muscle is treated as a structure composed of serially linked different mechanical properties parts)
'New politics', crisis effects and format effects : a comparative study of hostility and positivity in exchanges between leaders during UK Prime Minister's questions and Scottish and Welsh First Minister's questions
Existing research on party leader questioning in legislatures usually focuses on single case studies, less-than-ideal behaviours across leaders, and often post-election periods. Our article compares hostility and positivity in behaviours across three parliaments and, because of the COVID-19 crisis, across different time periods and modes of operation (live, hybrid, and online) while controlling for the same leaders. Using content analysis at the sentence level (N?=?3554), our data contrast parliamentary leader hostility and positivity levels in the UK, Scottish, and Welsh Parliaments across three time periods: pre-COVID-19, initial, and lockdown COVID-19. Findings for positivity are mixed, but for hostility, we find that while the initial shock of the COVID-19 crisis suppressed hostility, Westminster has higher ratios of hostility across all three time periods, and that format of operation has little effect on behaviour. Findings suggest less hostility in Scotland and Wales than in Westminster adding possible weight to ?new politics? arguments
The trials on the influence of knapsack sprayer technical condition on operator exposure as an input to the risk assessment for human health
Operator exposure to spray applied with knapsack sprayers was measured in the open field during the spraying of the low, medium and high plants (strawberries, young apple orchard and bearing fruits one). The samples were attached to the protective clothes in 13 locations. The BSF fluorescent tracer was added to the spray. The operator exposure was expressed as the part of the dose applied (ppm). The data on operator exposure was used to predict the risk for operator. The risk for humans was done by computer modeling according to German BBA model, taking into account field data for different sprayer technical conditions and 15 different pesticides. The most important influence of the sprayer technical condition on the operator exposition and the human health risk was observed for high crops
Putrescine catabolism via DAO contributes to proline and GABA accumulation in roots of lupine seedlings growing under salt stress
The levels of polyamines (PAs), proline (Pro), and γ-aminobutyric acid (GABA) as well as the activity of diamine oxidase (DAO; EC 1.4.3.6) were studied in the roots of 2-day-old lupine (Lupinus luteus L. ‘Juno’) seedlings treated with 200 mM NaCl for 24 h. The effect of adding 1 mM aminoguanidine (AG), an inhibitor of DAO activity, was also analyzed. It was found that in roots of lupine seedlings growing under salt stress, a negative correlation between Pro accumulation and putrescine (Put) content takes place. Pro level increased in roots by about 160% and, at the same time, Put content decreased by about 60%, as a result of ca. twofold increase of DAO activity. The AG added to the seedlings almost totally inhibited the activity of DAO, increased Put accumulation to control level, decreased Pro content by about 25%, and reduced GABA level by about 22%. Addition of 50 mM GABA to the lupine seedlings growing in the presence of AG and NaCl restored Pro content in roots to its level in NaCl-treated plants. In this research, the clear correlation between Put degradation and GABA and Pro accumulation was shown for the first time in the roots of seedlings growing under salt stress. This could be considered as a short-term response of a plant to high salt concentration. Our findings indicate that during intensive Pro accumulation in roots induced by salt stress, the pool of this amino acid is indirectly supported by GABA production as a result of Put degradation
Построение некоторых функций функций в гиперкомплексной числовой системе 4-го порядка
Рассмотрены вопросы построения таких обратных функций как логарифм, гиперболические и тригонометрические арксинус и арккосинус. Приведены примеры построения обратных функций для гиперкомплексной числовой системы 4-го порядка.Розглянуто питання побудови таких обернених функцій як логарифм, тригонометричні та гіперболічні арксинус і арккосинус. Наведено приклади побудови обернених функцій для гіперкомплексної системи 4-го порядку.Questions of construction of such inverse functions as the logarithm, hyperbolic and trigonometrical arc sine and arc cosine are considered. Examples of construction of inverse functions for the 4th order hypercomplex numerical system are given
Inter-population variations in concentrations, determinants of and correlations between 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE): a cross-sectional study of 3161 men and women from Inuit and European populations.
The study is part of a collaborative project (Inuendo), aiming to assess the impact of dietary persistent organochlorine pollutants (POPs) on human fertility. The aims with the present study are to analyze inter-population variations in serum concentrations of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE), to assess inter-population variations in biomarker correlations, and to evaluate the relative impact of different determinants for the inter-individual variations in POP-biomarkers. CB-153 concentrations were much higher in Inuits and Swedish fishermen's populations than in the populations from Eastern Europe, whereas the pattern was different for p,p'-DDE showing highest concentrations in the Kharkiv population. The correlations between the POP-biomarkers varied considerably between the populations, underlining that exposure sources differ and that the choice of representative biomarkers of overall POP exposure has to be based on an analysis of the specific exposure situation for each population. Age and gender were consistent determinants of serum POPs; seafood was of importance only in the Inuit and Swedish populations
Fertility in four regions spanning large contrasts in serum levels of widespread persistent organochlorines: a cross-sectional study
BACKGROUND: Persistent organochlorine pollutants (POPs) may interfere with reproductive function but direct evidence in humans is very limited. METHODS: Fertility was examined in four regions with contrasting blood levels of POPs. Pregnant women and their partners in Warsaw (Poland), Kharkiv (Ukraine) and Greenland were consecutively enrolled during antenatal visits. Swedish fishermen and their spouses were recruited separately and independently of current pregnancy. Lipid adjusted serum concentrations of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (DDE) were available for both partners. Time to pregnancy interviews were obtained among 2269 women and 798 men provided a semen sample. RESULTS: Inuits had high levels of both POP markers, Swedish fishermen were high in CB-153 but low in DDE, men from Kharkiv were high in DDE and low in CB-153 while men from Warsaw were low in CB-153 and had intermediate DDE levels. Compared to Warsaw couples, fecundability was reduced among couples from Kharkiv [adjusted fecundability ratio (FR) 0.64 (95% CI 0.5-0.8)] and elevated in Swedish fishermen families [FR 1.26 (95% CI 1.0-1.6)]. Adjusted geometric means of sperm counts and morphology did not differ between regions while sperm motility was higher in men living in Warsaw. CONCLUSION: We observed regional differences in time to pregnancy and sperm motility that may be related to regional differences in POP blood levels, but other interpretations are also plausible. In particular, differences in access to safe contraception and in the prevalence of contraceptive failures are most likely to bias comparisons of time to pregnancy
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