13,110 research outputs found
Correction of laser range tracking data for atmospheric refraction at elevations above 10 degrees
A formula for correcting laser measurements of satellite range for the effect of atmospheric refraction is given. The corrections apply above 10 deg elevation to satellites whose heights exceed 70 km. The meteorological measurements required are the temperature, pressure, and relative humidity of the air at the laser site at the time of satellite pass. The accuracy of the formula was tested by comparison with corrections obtained by ray-tracing radiosonde profiles. The standard deviation of the difference between the refractive retardation given by the formula and that calculated by ray-tracing was less than about 0.04% of the retardation or about 0.5 cm at 10 deg elevation, decreasing to 0.04 cm near zenith
Self-propulsion against a moving membrane: enhanced accumulation and drag force
Self-propulsion (SP) is a main feature of active particles (AP), such as
bacteria or biological micromotors, distinguishing them from passive colloids.
A renowned consequence of SP is accumulation at static interfaces, even in the
absence of hydrodynamic interactions. Here we address the role of SP in the
interaction between AP and a moving semipermeable membrane. In particular, we
implement a model of noninteracting AP in a channel crossed by a partially
penetrable wall, moving at a constant velocity . With respect to both the
cases of passive colloids with and AP with , the AP with finite
show enhancement of accumulation in front of the obstacle and experience a
largely increased drag force. This effect is understood in terms of an
effective potential localised at the interface between particles and membrane,
of height proportional to , where is the AP's re-orientation
time and the width characterising the surface's smoothness (
for hard core obstacles). An approximate analytical scheme is able to reproduce
the observed density profiles and the measured drag force, in very good
agreement with numerical simulations. The effects discussed here can be
exploited for automatic selection and filtering of AP with desired parameters.Comment: 13 pages, 3 figure
Metadynamic sampling of the free energy landscapes of proteins coupled with a Monte Carlo algorithm
Metadynamics is a powerful computational tool to obtain the free energy
landscape of complex systems. The Monte Carlo algorithm has proven useful to
calculate thermodynamic quantities associated with simplified models of
proteins, and thus to gain an ever-increasing understanding on the general
principles underlying the mechanism of protein folding. We show that it is
possible to couple metadynamics and Monte Carlo algorithms to obtain the free
energy of model proteins in a way which is computationally very economical.Comment: Submitted to Gen
How Do Maternal Subclinical Symptoms Influence Infant Motor Development during the First Year of Life?
An unavoidable reciprocal influence characterizes the mother-child dyad. Within this relationship, the presence of depression, somatization, hostility, paranoid ideation, and interpersonal sensitivity symptoms at a subclinical level and their possible input on infant motor competences has not been yet considered. Bearing in mind that motor abilities represent not only an indicator of the infant\u2019s health-status, but also the principal field to infer his/her needs, feelings and intentions, in this study the quality of infants\u2019 movements were assessed and analyzed in relationship with the maternal attitudes. The aim of this research was to investigate if/how maternal symptomatology may pilot infant\u2019s motor development during his/her first year of life by observing the characteristics of motor development in infants aged 0\u201311 months. Participants included 123 mothers and their infants (0\u201311 months-old). Mothers\u2019 symptomatology was screened with the Symptom Checklist-90-Revised (SCL-90-R), while infants were tested with the Peabody Developmental Motor Scale-Second Edition. All dyads belonged to a non-clinical population, however, on the basis of SCL-90-R scores, the mothers\u2019 sample was divided into two groups: normative and subclinical. Descriptive, t-test, correlational analysis between PDMS-2 scores and SCL-90-R results are reported, as well as regression models results. Both positive and negative correlations were found between maternal perceived symptomatology, Somatization (SOM), Interpersonal Sensitivity (IS), Depression (DEP), Hostility (HOS), and Paranoid Ideation (PAR) and infants\u2019 motor abilities. These results were further verified by applying regression models to predict the infant\u2019s motor outcomes on the basis of babies\u2019 age and maternal status. The presence of positive symptoms in the SCL-90-R questionnaire (subclinical group) predicted good visual-motor integration and stationary competences in the babies. In particular, depressive and hostility feelings in mothers seemed to induce an infant motor behavior characterized by a major control of the environmental space. When mothers perceived a higher level of hostility and somatization, their babies showed difficulties in sharing action space, such as required in the development of stationary positions and grasping abilities. In a completely different way, when infants can rely on a mother with low-perceived symptoms (normative group) his/her motor performances develop with a higher degree of freedom/independence. These findings suggest, for the first time, that even in a non- clinical sample, mother\u2019s perceived-symptoms can produce important consequences not in infant motor development as a whole, but in some specific areas, contributing to shape the infant\u2019s motor ability and his/her capability to act in the world
Dyspnoea and hypoxaemia after lung surgery: the role of interatrial right-to-left shunt
Strategi Training Within Industry sebagai Upaya Peningkatan Kepercayaan Diri Siswa pada Mata Pelajaran Pengolahan Makanan Kontinental
Practices in Vocational High Schools hold an important role, because through practices, students could master the skills optimally. Confidence is a significant aspect that should be owned by students to conduct the practices. However in the field, there were several students of grade XI Jasa Boga I of SMKN 1 Sewon who had low confidence in the Continental Cuisine Practice. This was indicated by the hesitation of the students in conducting the practices. Every group depended on the teacher' assistance. This action research was conducted in three cycles that consisted of planning, implementation, observation, and reflection. The results of the study showed an improvement of the students' confidence from 2.49 become 2.66 and 2.86 in the subject of Continental Cuisine through Training within Industry Strategy
Which is the temperature of granular systems? A mean field model of free cooling inelastic mixtures
We consider a mean field model describing the free cooling process of a two
component granular mixture, a generalization of so called Maxwell model. The
cooling is viewed as an ordering process and the scaling behavior is attributed
to the presence of an attractive fixed point at for the dynamics. By
means of asymptotic analysis of the Boltzmann equation and of numerical
simulations we get the following results: 1)we establish the existence of two
different partial granular temperatures, one for each component, which violates
the Zeroth Law of Thermodynamics; 2) we obtain the scaling form of the two
distribution functions; 3) we prove the existence of a continuous spectrum of
exponents characterizing the inverse-power law decay of the tails of the
velocity, which generalizes the previously reported value 4 for the pure model;
4) we find that the exponents depend on the composition, masses and restitution
coefficients of the mixture; 5) we also remark that the reported distributions
represent a dynamical realization of those predicted by the Non Extensive
Statistical Mechanics, in spite of the fact that ours stem from a purely
dynamical approach.Comment: 23 pages, 9 figures. submitted for publicatio
Annotating Croatian Semantic Type Coercions in CROATPAS
This research paper presents the results of a corpus-based metonymy annotation exercise on a sample of 101 Croatian verb entries – corresponding to 457 patters and over 20,000 corpus lines – taken from CROATPAS (Marini & Ježek, 2019), a digital repository of verb argument structures manually annotated with Semantic Type labels on their argument slots following a methodology inspired by Corpus Pattern Analysis (Hanks, 2004 & 2013; Hanks & Pustejovsky, 2005). CROATPAS will be made available online in 2020. Semantic Type labelling is not only well-suited to annotate verbal polysemy, but also metonymic shifts in verb argument combinations, which in Generative Lexicon (Pustejovsky, 1995 & 1998; Pustejovsky & Ježek, 2008) are called Semantic Type coercions. From a sub lexical point of view, Semantic Type coercions can be considered as exploitations of one of the qualia roles of those Semantic Types which do not satisfy a verb’s selectional requirements, but do not trigger a different verb sense. Overall, we were able to identify 62 different Semantic Type coercions linked to 1,052 metonymic corpus lines. In the future, we plan to compare our results with those from an equivalent study on Italian verbs (Romani, 2020) for a crosslinguistic analysis of metonymic shifts
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