260 research outputs found
Krótkie rozważania na temat cierpienia człowieka chorego
W pracy przedstawiono krótkie rozważania na temat cierpienia człowieka chorego. Zwrócono uwagę na różne definicje cierpienia. Odwołano się m.in. do definicji encyklopedycznych, czy poglądów Jana Pawła II na temat cierpienia.The paper briefly discusses the problem of the suffering of the ill. Several definitions of suffering have been brought to attention. References have been made to both encyclopaedic definitions and John Paul II’s views on suffering
Spatial clustering of interacting bugs: Levy flights versus Gaussian jumps
A biological competition model where the individuals of the same species
perform a two-dimensional Markovian continuous-time random walk and undergo
reproduction and death is studied. The competition is introduced through the
assumption that the reproduction rate depends on the crowding in the
neighborhood. The spatial dynamics corresponds either to normal diffusion
characterized by Gaussian jumps or to superdiffusion characterized by L\'evy
flights. It is observed that in both cases periodic patterns occur for
appropriate parameters of the model, indicating that the general macroscopic
collective behavior of the system is more strongly influenced by the
competition for the resources than by the type of spatial dynamics. However,
some differences arise that are discussed.Comment: This version incorporates in the text the correction published as an
Erratum in Europhysics Letters (EPL) 95, 69902 (2011) [doi:
10.1209/0295-5075/95/69902
The influence of prenatal exposure to tobacco smoke on neonatal body proportions
The objective of this study was to determine neonatal anthropometric indices such as: birth weight, crown-heel
length, head and chest circumference and ponderal index
,
in relation to the maternal smoker status (active and
passive smoking). The study included 147 neonates born in 2003-2004 at the Princess Anna Mazowiecka University
Hospital in Warsaw admitted to the Neonatal and Intensive Care Department of Warsaw Medical University. Neonates
were assigned to one of three groups: babies of mothers who were active smokers, passive smokers and non-smokers
based on a questionnaire concerning exposure to tobacco smoke and on the concentration of cotinine in maternal
urine. The babies of mothers who were active smokers were born with lower birth weight (p=0.033), lower crown-heel
length (p=0.026), lower head circumference (p=0.002) and lower chest circumference (p=0.021) significantly more
often than babies of non-smoker mothers. Babies whose mothers were active smokers had an increased risk of
lower head circumference or 3, 9 (1, 4-10, 7, CI 95%), and an increased risk of lower chest circumference OR 4, 0 (1,
5-10, 9, CI 95%). The babies of mothers who were passive smokers also had lower anthropometric indices, but the
differences were not statistically significant. No effect on ponderal index was observed among the neonates whose
mothers were active and passive smokers. Smoking during pregnancy causes symmetrical restriction of intrauterine
growth
The impact of intrauterine tobacco exposure on the cerebral mass of the neonate based on the measurement of head circumference
The objective of the study was to assess cerebral mass, based on head circumfer-
ence measurements in neonates exposed to tobacco smoke in utero, and to deter-
mine the relative proportions of the cerebral and body mass. The study included
147 neonates born in the period 2003–2004 at the Princess Anna Mazowiecka University Hospita land admitted to the Neonatal and Intensive Care Department of the Medical University in Warsaw. Subjects were divided into three groups on the basis of maternal status as active, passive, or nonsmokers determined by materna lurinary cotinine concentration and a questionnaire. Neonates whose mothers were active smokers throughout the whole period of pregnancy had a lower head circumference and in consequence a lower cerebral mass significantly more frequently when compared with those whose mothers were nonsmokers, P=0.002. (Median difference in cerebral mass was 48.27 g.) The risk of lower cerebral mass was 3.9 (1.4–10.8, CI 95%) in the group of neonates whose mothers actively smoked cigarettes during pregnancy. A negative correlation was seen between cerebral mass and maternal urinary cotinine concentration (correlation coefficient r=−23, P=0.006). The ratio of the cerebral to body mass was similar for neonates in all three groups. Active smoking during pregnancy had a negative effect on the cerebral mass of theneonate, however no such effect was observed in neonates whose mothers were passive smokers. The deficiency in cerebral mass increased with greater smoking intensity. Active smoking by the mother during pregnancy inhibits the growth of the brain as well as that of the body mass of the neonate
Emerging Concepts Impacting Head and Neck Cancer Surgery Morbidity
All treatment modalities for head and neck cancer carry with them a risk of adverse events. Head and neck surgeons are faced with significant challenges to minimize associated morbidity and manage its sequelae. Recognizing situations in which a surgical complication is an adverse event inherent to the procedure can alleviate the psychologic impact a complication might have on the treatment team and minimize external and internal pressures. Focusing on the complications that can be effectively modified, future complications can be avoided. Also, some surgical morbidities may not be preventable, necessitating the option to reconsider whether the incidents should be labeled toxic reactions rather than a complication. This discussion highlights some of the areas in which additional research is needed to achieve the goal of minimizing the impact of surgical morbidity.Peer reviewe
Neel probability and spin correlations in some nonmagnetic and nondegenerate states of hexanuclear antiferromagnetic ring Fe6: Application of algebraic combinatorics to finite Heisenberg spin systems
The spin correlations \omega^z_r, r=1,2,3, and the probability p_N$ of
finding a system in the Neel state for the antiferromagnetic ring Fe(III)6 (the
so-called `small ferric wheel') are calculated. States with magnetization M=0,
total spin 0<=S<=15 and labeled by two (out of four) one-dimensional
irreducible representations (irreps) of the point symmetry group D_6 are taken
into account. This choice follows from importance of these irreps in analyzing
low-lying states in each S-multiplet. Taking into account the Clebsch--Gordan
coefficients for coupling total spins of sublattices (SA=SB=15/2) the global
Neel probability p*_N can be determined. Dependencies of these quantities on
state energy (per bond and in the units of exchange integral J) and the total
spin S are analyzed. Providing we have determined p_N(S) etc. for other
antiferromagnetic rings (Fe10, for instance) we could try to approximate
results for the largest synthesized ferric wheel Fe18. Since thermodynamic
properties of Fe6 have been investigated recently, in the present
considerations they are not discussed, but only used to verify obtained values
of eigenenergies. Numerical results re calculated with high precision using two
main tools: (i) thorough analysis of symmetry properties including methods of
algebraic combinatorics and (ii) multiple precision arithmetic library GMP. The
system considered yields more than 45 thousands basic states (the so-called
Ising configurations), but application of the method proposed reduces this
problem to 20-dimensional eigenproblem for the ground state (S=0). The largest
eigenproblem has to be solved for S=4; its dimension is 60. These two facts
(high precision and small resultant eigenproblems) confirm efficiency and
usefulness of such an approach, so it is briefly discussed here.Comment: 13 pages, 7 figs, 5 tabs, revtex
Impact of Unexpected Events, Shocking News and Rumours on Foreign Exchange Market Dynamics
We analyze the dynamical response of the world's financial community to
various types of unexpected events, including the 9/11 terrorist attacks as
they unfolded on a minute-by-minute basis. We find that there are various
'species' of news, characterized by how quickly the news get absorbed, how much
meaning and importance is assigned to it by the community, and what subsequent
actions are then taken. For example, the response to the unfolding events of
9/11 shows a gradual collective understanding of what was happening, rather
than an immediate realization. For news items which are not simple economic
statements, and hence whose implications are not immediately obvious, we
uncover periods of collective discovery during which collective opinions seem
to oscillate in a remarkably synchronized way. In the case of a rumour, our
findings also provide a concrete example of contagion in inter-connected
communities. Practical applications of this work include the possibility of
producing selective newsfeeds for specific communities, based on their likely
impact
Spray‐Dried Mesoporous Mixed Cu‐Ni Oxide@Graphene Nanocomposite Microspheres for High Power and Durable Li‐Ion Battery Anodes
Exfoliated graphene‐wrapped mesoporous Cu‐Ni oxide (CNO) nanocast composites are developed using a straightforward nanostructure engineering strategy. The synergistic effect of hierarchical mesoporous CNO nanobuilding blocks that are homogeneously wrapped by graphene nanosheets (GNSs) using a rapid spray drying technique effectively preserves the electroactive species against the volume changes resulting from the charge/discharge process. Owing to the intriguing structural/morphological features arising from the caging effect of exfoliated graphene sheets, these 3D/2D CNO@GNS nanocomposite microspheres are promising as high‐performance Li‐ion battery anode materials. They exhibit unprecedented electrochemical behavior, such as high reversible specific capacity (initial discharge capacities exceeding 1700 mAh g−1 at low 0.1 mA g−1, stable 850 and 730 mAh g−1 at 1 and 5 mA g−1 after 800 and 1300 cycles, respectively, and higher than 400 mAh g−1 at very high current density of 10 mA g−1 after more than 2000 cycles), excellent coulombic efficiency and long‐term stability (more than 3000 cycles with >55% capacity retention) at high current density that are remarkable compared to most transition metal oxides and nanocomposites prepared by conventional techniques. This simple, yet innovative, material design is inspiring to develop advanced conversion materials for Li‐ion batteries or other energy storage devices
Magnetic translation groups in an n-dimensional torus
A charged particle in a uniform magnetic field in a two-dimensional torus has
a discrete noncommutative translation symmetry instead of a continuous
commutative translation symmetry. We study topology and symmetry of a particle
in a magnetic field in a torus of arbitrary dimensions. The magnetic
translation group (MTG) is defined as a group of translations that leave the
gauge field invariant. We show that the MTG on an n-dimensional torus is
isomorphic to a central extension of a cyclic group Z_{nu_1} x ... x
Z_{nu_{2l}} x T^m by U(1) with 2l+m=n. We construct and classify irreducible
unitary representations of the MTG on a three-torus and apply the
representation theory to three examples. We shortly describe a representation
theory for a general n-torus. The MTG on an n-torus can be regarded as a
generalization of the so-called noncommutative torus.Comment: 29 pages, LaTeX2e, title changed, re-organized, to be published in
Journal of Mathematical Physic
HIRDES - The High-Resolution Double-Echelle Spectrograph for the World Space Observatory Ultraviolet (WSO/UV)
The World Space Observatory Ultraviolet (WSO/UV) is a multi-national project
grown out of the needs of the astronomical community to have future access to
the UV range. WSO/UV consists of a single UV telescope with a primary mirror of
1.7m diameter feeding the UV spectrometer and UV imagers. The spectrometer
comprises three different spectrographs, two high-resolution echelle
spectrographs (the High-Resolution Double-Echelle Spectrograph, HIRDES) and a
low-dispersion long-slit instrument. Within HIRDES the 102-310nm spectral band
is split to feed two echelle spectrographs covering the UV range 174-310nm and
the vacuum-UV range 102-176nm with high spectral resolution (R>50,000). The
technical concept is based on the heritage of two previous ORFEUS SPAS
missions. The phase-B1 development activities are described in this paper
considering performance aspects, design drivers, related trade-offs (mechanical
concepts, material selection etc.) and a critical functional and environmental
test verification approach. The current state of other WSO/UV scientific
instruments (imagers) is also described.Comment: Accepted for publication in Advances in Space Researc
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