34 research outputs found
Self-similar stable processes arising from high-density limits of occupation times of particle systems
We extend results on time-rescaled occupation time fluctuation limits of the
-branching particle system with Poisson initial condition. The earlier results in the homogeneous case
(i.e., with Lebesgue initial intensity measure) were obtained for dimensions
only, since the particle system becomes locally extinct if
. In this paper we show that by introducing high density
of the initial Poisson configuration, limits are obtained for all dimensions,
and they coincide with the previous ones if . We also give
high-density limits for the systems with finite intensity measures (without
high density no limits exist in this case due to extinction); the results are
different and harder to obtain due to the non-invariance of the measure for the
particle motion. In both cases, i.e., Lebesgue and finite intensity measures,
for low dimensions ( and
, respectively) the limits are determined by
non-L\'evy self-similar stable processes. For the corresponding high dimensions
the limits are qualitatively different: -valued L\'evy
processes in the Lebesgue case, stable processes constant in time on
in the finite measure case. For high dimensions, the laws of all
limit processes are expressed in terms of Riesz potentials. If , the
limits are Gaussian. Limits are also given for particle systems without
branching, which yields in particular weighted fractional Brownian motions in
low dimensions. The results are obtained in the setup of weak convergence of
S'(R^d)$-valued processes.Comment: 28 page
Oscillatory Fractional Brownian Motion and Hierarchical Random Walks
We introduce oscillatory analogues of fractional Brownian motion,
sub-fractional Brownian motion and other related long range dependent Gaussian
processes, we discuss their properties, and we show how they arise from
particle systems with or without branching and with different types of initial
conditions, where the individual particle motion is the so-called c-random walk
on a hierarchical group. The oscillations are caused by the discrete and
ultrametric structure of the hierarchical group, and they become slower as time
tends to infinity and faster as time approaches zero. We also give other
results to provide an overall picture of the behavior of this kind of systems,
emphasizing the new phenomena that are caused by the ultrametric structure as
compared with results for analogous models on Euclidean space
Sperm midpiece apoptotic markers: impact on fertilizing potential in in vitro fertilization and intracytoplasmic sperm injection
The Effectiveness of Family Constellation Therapy in Improving Mental Health:A Systematic ReviewPalabras clave(sic)(sic)(sic)
Family/systemic constellation therapy is a short-term group intervention aiming to help clients better understand and then change their conflictive experiences within a social system (e.g., family). The aim of the present systematic review was to synthetize the empirical evidence on the tolerability and effectiveness of this intervention in improving mental health. The PsycINFO, Embase, MEDLINE, ISI Web of Science, Psyndex, PsycEXTRA, ProQuest Dissertations & Theses, The Cochrane Library, Google Scholar, and an intervention-specific organization's databases were searched for quantitative, prospective studies published in English, German, Spanish, French, Dutch or Hungarian up until April 2020. Out of 4,197 identified records, 67 were assessed for eligibility, with 12 studies fulfilling inclusion criteria (10 independent samples; altogether 568 participants). Outcome variables were diverse ranging from positive self-image through psychopathology to perceived quality of family relationships. Out of the 12 studies, nine showed statistically significant improvement postintervention. The studies showing no significant treatment benefit were of lower methodological quality. The random-effect meta-analysis-conducted on five studies in relation to general psychopathology-indicated a moderate effect (Hedges' g of 0.531, CI: 0.387-0.676). Authors of seven studies also investigated potential iatrogenic effects and four studies reported minor or moderate negative effects in a small proportion (5-8%) of participants that potentially could have been linked to the intervention. The data accumulated to date point into the direction that family constellation therapy is an effective intervention with significant mental health benefits in the general population; however, the quantity and overall quality of the evidence is low
Development and Validation of a Path Length Calculation for Carotid-Femoral Pulse Wave Velocity Measurement: A TASCFORCE, SUMMIT, and Caerphilly Collaborative Venture.
Current distance measurement techniques for pulse wave velocity (PWV) calculation are susceptible to intercenter variability. The aim of this study was to derive and validate a formula for this distance measurement. Based on carotid femoral distance in 1183 whole-body magnetic resonance angiograms, a formula was derived for calculating distance. This was compared with distance measurements in 128 whole-body magnetic resonance angiograms from a second study. The effects of recalculation of PWV using the new formula on association with risk factors, disease discrimination, and prediction of major adverse cardiovascular events were examined within 1242 participants from the multicenter SUMMIT study (Surrogate Markers of Micro- and Macrovascular Hard End-Points for Innovative Diabetes Tools) and 825 participants from the Caerphilly Prospective Study. The distance formula yielded a mean error of 7.8 mm (limits of agreement =-41.1 to 56.7 mm; P<0.001) compared with the second whole-body magnetic resonance angiogram group. Compared with an external distance measurement, the distance formula did not change associations between PWV and age, blood pressure, or creatinine (P<0.01) but did remove significant associations between PWV and body mass index (BMI). After accounting for differences in age, sex, and mean arterial pressure, intercenter differences in PWV persisted using the external distance measurement (F=4.6; P=0.004), whereas there was a loss of between center difference using the distance formula (F=1.4; P=0.24). PWV odds ratios for cardiovascular mortality remained the same using both the external distance measurement (1.14; 95% confidence interval, 1.06-1.24; P=0.001) and the distance formula (1.17; 95% confidence interval, 1.08-1.28; P<0.001). A population-derived automatic distance calculation for PWV obtained from routinely collected clinical information is accurate and removes intercenter measurement variability without impacting the diagnostic utility of carotid-femoral PWV
Limits of concepts – picturebook, comic book, graphic novel
Artykuł analizuje wzajemne relacje książki obrazkowej i komiksu – to, w jaki sposób te pojęcia są definiowane i jakimi środkami wyrazu się posługują, ich części wspólne oraz różnice. Ukazuje pokrótce historię kształtowania się gatunków oraz sposoby, za pomocą których twórcy budują ikonoteksty. Przedstawione są tu także wybrane przykłady artystów tworzących na pograniczu obu gatunków. Końcowa analiza zawarta w tekście dowodzi, że każdy komiks jest książką obrazkową, jednak nie każda książka obrazkowa jest komiksem, należy jednak pamiętać, że granice między gatunkami są płynne i ulegają ciągłym przesunięciom dzięki twórczym eksperymentom i rozwojowi druku.The article analyzes the mutual relations of a picturebook and a comic book - how these concepts are defined and what means of expression they applye, their common parts and differences. It shows briefly the history of geners formation and the process of creating build iconotexts. There are also selected examples of artists creating on the borderline of genres. The final analysis proves that every comic is a picture book, but not all picturebook is a comic. However it must be taken into consideration that the boundaries between genres are fluid and are constantly shifting thanks to creative experiments and the development of printing
Simulation of loads of multi-role aggregate for ploughless soil tillage
W artykule zaprezentowano praktyczne możliwości wykorzystania systemu MES w uzyskaniu dokładnej i wiarygodnej oceny stanu naprężeń i odkształceń konstrukcji agregatu do bezorkowej uprawy gleby. Przedstawiono wyniki w postaci map naprężeń oraz przemieszczeń konstrukcji oraz zaproponowano zmiany konstrukcyjne mające na celu obniżenie poziomu naprężeń w miejscach gdzie ich poziom jest zbyt wysoki.In the paper presented are practical possibilities of FEM system when used for obtaining the exact and reliable assessment of stresses and strains oft he structure of aggregate for ploughless soil tillage. Presented are also results in the form of a map showing stresses and strains of the aggregate structure and suggested are changes in its design in order to lower the level of the stresses in places where they are too high
Application of neural network models for assessment and forecasting of air quality
W artykule przedstawiono metodę oceny i prognozowania jakości powietrza opartą na modelu sztucznej sieci neuronowej. Metoda ta ze względu na dobre właściwości uogólniające i szybkie osiąganie wyników nadaje się do rozwiązywania zadań predykcyjnych, których przykładem jest prognozowanie sytuacji ostrzegawczych. Dla rozwiązania postawionego zadania zaproponowano czterowarstwową, jednokierunkową sieć neuronową. Sieć tego typu jest obiecującym narzędziem oceny i prognozowania powietrza, zwłaszcza w sytuacjach podwyższonych stężeń zanieczyszczeń wpływających niekorzystnie na zdrowie ludzi i otaczające środowisko.The paper deals on the air pollution assessment and forecasting method based on artificial neural network. For solving the problem the four-layer, feed-forward neural network is proposed. The method has good properties of generalisation and high speed of operation. In this aspect artificial neural network can be regarded as good instrument for prediction of smog state. The chosen type of the network seems to be the promised tool for assessment and forecasting of states, which influence people health and the surrounded environment
Estimation of the front tool used in the tilling-and-sowing set
Przedstawiono konstrukcję zestawu uprawowego, składającego się z narzędzia przedniego i agregatu tylnego, ze sprzęgiem do siewnika, opracowanego w ramach projektu celowego, we współpracy Przemysłowego Instytutu Maszyn Rolniczych w Poznaniu z firmą BOMET-Węgrów. Omówiono wpływ narzędzia przedniego na jakość doprawienia gleby przed siewnikiem oraz obciążenie współpracującego ciągnika w transporcie.This paper presents a construction of tilling-and-sowing set consisting of the front tool and rear cultivation aggregator with drill coupler, elaborated within oriented project in cooperation between PIMR-Poznań and BOMET-Węgrów company. Influence of used front tool on quality of the soil before secondary tillage sowing and load of the cooperating tractor in transport are shown
THE ROLE OF ESCORENA (EUROPEAN SYSTEM OF COOPERATIVE RESEARCH NETWORKS IN AGRICULTURE) IN AGRICULTURE KNOWLEDGE SHARING AND TECHNOLOGY TRANSFER
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