429 research outputs found
Journal Staff
This book constitutes the refereed proceedings of the 18th Scandinavian Conference on Image Analysis, SCIA 2013, held in Espoo, Finland, in June 2013. The 67 revised full papers presented were carefully reviewed and selected from 132 submissions. The papers are organized in topical sections on feature extraction and segmentation, pattern recognition and machine learning, medical and biomedical image analysis, faces and gestures, object and scene recognition, matching, registration, and alignment, 3D vision, color and multispectral image analysis, motion analysis, systems and applications, human-centered computing, and video and multimedia analysis
Combination therapy with an ACE inhibitor and an angiotensin receptor blocker for diabetic nephropathy - a meta-analysis
WSTĘP. Inhibitory konwertazy angiotensyny (ACEI)
i blokery receptora angiotensyny (ARB) zapobiegają
progresji nefropatii cukrzycowej (DN). Wyniki badań
sugerują, że połączenie układu renina-angiotensyna-aldosteron (RAAS) i czynników hamujących działa
addytywnie w procesie leczenia DN. Ponieważ badania
te obejmowały niewielkie grupy chorych, autorzy niniejszej pracy przeprowadzili metaanalizę
prób dotyczących leczenia skojarzonego DN.
METODY. Badania do metaanalizy wybrano na podstawie
baz danych MEDLINE, EMBASE, CINAHL i Cochrane.
Włączono wszystkie próby dotyczące skojarzonego
leczenia za pomocą ACEI i ARB. Głównym
punktem końcowym było dobowe wydalanie białka
z moczem, a dodatkowe punkty końcowe obejmowały: wartości ciśnienia tętniczego, stężenia potasu
we krwi i współczynnika przesączania kłębuszkowego
(GFR).
WYNIKI. W 10 włączonych do analizy badaniach
156 chorych otrzymało ACEI i ARB, a 159 jedynie ACEI. Większość badań trwało 8-12 tygodni. U osób
leczonych ACEI i ARB uzyskano zmniejszenie proteinurii
(p = 0,01), co wiązało się ze znaczną statystyczną heterogenicznością (p = 0,005). Terapia ACEI
i ARB była związana ze zmniejszeniem GFR [3,87 ml/min
(7,32-0,42); p = 0,03] i tendencją do wzrostu stężenia
kreatyniny w surowicy (6,86 umol/l 95% CI -0,76-13,73; p = 0,09). Stężenie potasu zwiększyło się
o 0,2 (0,08-0,32) mmol/l (p < 0,01) u chorych leczonych
ACEI i ARB. Skurczowe i rozkurczowe ciśnienie
krwi obniżyło się odpowiednio o 5,2 mm Hg (2,1-8,4) (p < 0,01) i 5,3 mm Hg (2,2-8,4) (p < 0,01).
WNIOSKI. Wyniki metaanalizy sugerują, że łączne stosowanie
ACEI + ARB w większym stopniu zmniejsza
24-godzinne wydalanie białka z moczem niż przyjmowanie
jedynie ACEI. Korzystne efekty terapii skojarzonej
są wynikiem niewielkiego wpływu leków na
GFR, stężenie kreatyniny i potasu w surowicy oraz
ciśnienie tętnicze. Rezultaty te należy interpretować
ostrożnie, ponieważ większość analizowanych badań charakteryzowała się krótkim czasem obserwacji,
a w kilku długoterminowych próbach (12 miesięcy) nie wykazano korzystnego wpływu leczenia.AIMS. Angiotensin-converting enzyme inhibitors
(ACEIs) and angiotensin receptor blockers (ARBs)
prevent the progression of diabetic nephropathy (DN).
Studies suggest that combination renin-angiotensin-aldosterone system (RAAS)-inhibiting therapy provides
additive benefit in DN. However, these studies
are small in size. We performed a meta-analysis of
studies investigating combination therapy for DN.
METHODS. Studies were identified through a search
of MEDLINE, EMBASE, CINAHL and the Cochrane
Database. All trials involving combined ACEI and ARB
for slowing progression of DN were included. The
primary end point was 24-
Blood pressure, serum potassium and glomerular
filtration rate (GFR) were secondary end points.
RESULTS. In the 10 included trials, 156 patients received
ACEI + ARB and 159 received ACEI only. Most
studies were 8–12 weeks in duration. Proteinuria was
reduced with ACEI + ARB (p = 0.01). This was associated with significant statistical heterogeneity (p = 0.005). ACEI + ARB was associated with a reduction
in GFR [3.87 ml/min (7.32-0.42); p = 0.03] and
a trend towards an increase in serum creatinine (6.86
umol/l 95% CI: -0.76-13.73; p = 0.09). Potassium was
increased by 0.2 (0.08-0.32) mmol/l (p < 0.01) with
ACEI + ARB. Systolic and diastolic blood pressure were
reduced by 5.2 (2.1-8.4) mm Hg (p < 0.01) and 5.3
(2.2-8.4) mm Hg (p < 0.01), respectively.
CONCLUSIONS. This meta-analysis suggests that ACEI +
+ ARB reduces 24-h proteinuria to a greater extent
than ACEI alone. This benefit is associated with small
effects on GFR, serum creatinine, potassium and blood
pressure. These results should be interpreted cautiously
as most of the included studies were of short
duration and the few long-term studies (12 months)
have not demonstrated benefi
Non-Fermi-liquid behavior in the Kondo lattices induced by peculiarities of magnetic ordering and spin dynamics
A scaling consideration of the Kondo lattices is performed with account of
singularities in the spin excitation spectral function. It is shown that a
non-Fermi-liquid (NFL) behavior between two critical values of the bare
coupling constant occurs naturally for complicated magnetic structures with
several magnon branches. This may explain the fact that a NFL behavior takes
place often in the heavy-fermion systems with peculiar spin dynamics. Another
kind of a NFL-like state (with different critical exponents) can occur for
simple antiferromagnets with account of magnon damping, and for paramagnets,
especially with two-dimensional character of spin fluctuations. The mechanisms
proposed lead to some predictions about behavior of specific heat, resistivity,
magnetic susceptibility, and anisotropy parameter, which can be verified
experimentally.Comment: 16 pages, RevTeX, 4 Postscript figures. Extended versio
Multi-Channel Kondo Necklace
A multi--channel generalization of Doniach's Kondo necklace model is
formulated, and its phase diagram studied in the mean--field approximation. Our
intention is to introduce the possible simplest model which displays some of
the features expected from the overscreened Kondo lattice. The conduction
electron channels are represented by sets of pseudospins \vt_{j}, , which are all antiferromagnetically coupled to a periodic array of
|\vs|=1/2 spins. Exploiting permutation symmetry in the channel index
allows us to write down the self--consistency equation for general . For
, we find that the critical temperature is rising with increasing Kondo
interaction; we interpret this effect by pointing out that the Kondo coupling
creates the composite pseudospin objects which undergo an ordering transition.
The relevance of our findings to the underlying fermionic multi--channel
problem is discussed.Comment: 29 pages (2 figures upon request from [email protected]), LATEX,
submitted for publicatio
Genetic Homogeneity of the Invasive Lionfish Across the Northwestern Atlantic and the Gulf of Mexico Based On Single Nucleotide Polymorphisms
Despite the devastating impact of the lionfish (Pterois volitans) invasion on NW Atlantic ecosystems, little genetic information about the invasion process is available. We applied Genotyping by Sequencing techniques to identify 1,220 single nucleotide polymorphic sites (SNPs) from 162 lionfish samples collected between 2013 and 2015 from two areas chronologically identified as the first and last invaded areas in US waters: the east coast of Florida and the Gulf of Mexico. We used population genomic analyses, including phylogenetic reconstruction, Bayesian clustering, genetic distances, Discriminant Analyses of Principal Components, and coalescence simulations for detection of outlier SNPs, to understand genetic trends relevant to the lionfish’s long-term persistence. We found no significant differences in genetic structure or diversity between the two areas (FST p-values \u3e 0.01, and t-test p-values \u3e 0.05). In fact, our genomic analyses showed genetic homogeneity, with enough gene flow between the east coast of Florida and Gulf of Mexico to erase previous signals of genetic divergence detected between these areas, secondary spreading, and bottlenecks in the Gulf of Mexico. These findings suggest rapid genetic changes over space and time during the invasion, resulting in one panmictic population with no signs of divergence between areas due to local adaptation
Quantum phase transitions in the Bose-Fermi Kondo model
We study quantum phase transitions in the Bose-Fermi Kondo problem, where a
local spin is coupled to independent bosonic and fermionic degrees of freedom.
Applying a second order expansion in the anomalous dimension of the Bose field
we analyze the various non-trivial fixed points of this model. We show that
anisotropy in the couplings is relevant at the SU(2) invariant non Fermi liquid
fixed points studied earlier and thus the quantum phase transition is usually
governed by XY or Ising-type fixed points. We furthermore derive an exact
result that relates the anomalous exponent of the Bose field to that of the
susceptibility at any finite coupling fixed point. Implications on the
dynamical mean field approach to locally quantum critical phase transitions are
also discussed.Comment: 13 pages, 9 figures, some references added/correcte
On Traversable Lorentzian Wormholes in the Vacuum Low Energy Effective String Theory in Einstein and Jordan Frames
Three new classes (II-IV) of solutions of the vacuum low energy effective
string theory in four dimensions are derived. Wormhole solutions are
investigated in those solutions including the class I case both in the Einstein
and in the Jordan (string) frame. It turns out that, of the eight classes of
solutions investigated (four in the Einstein frame and four in the
corresponding string frame), massive Lorentzian traversable wormholes exist in
five classes. Nontrivial massless limit exists only in class I Einstein frame
solution while none at all exists in the string frame. An investigation of test
scalar charge motion in the class I solution in the two frames is carried out
by using the Plebanski-Sawicki theorem. A curious consequence is that the
motion around the extremal zero (Keplerian) mass configuration leads, as a
result of scalar-scalar interaction, to a new hypothetical "mass" that confines
test scalar charges in bound orbits, but does not interact with neutral test
particles.Comment: 18 page
Histopathology, vitellogenin and chemical body burden in mosquitofish (Gambusia holbrooki) sampled from six river sites receiving a gradient of stressors
There are over 40,000 chemical compounds registered for use in Australia, and only a handful are monitored in the aquatic receiving environments. Their effects on fish species in Australia are largely unknown. Mosquitofish (Gambusia holbrooki) were sampled from six river sites in Southeast Queensland identified as at risk from a range of pollutants. The sites selected were downstream of a wastewater treatment plant discharge, a landfill, two agricultural areas, and two sites in undeveloped reaches within or downstream of protected lands (national parks). Vitellogenin analysis, histopathology of liver, kidney and gonads, morphology of the gonopodium, and chemical body burden were measured to characterize fish health. Concentrations of trace organic contaminants (TrOCs) in water were analyzed by in vitro bioassays and chemical analysis. Estrogenic, anti-estrogenic, anti-androgenic, progestagenic and anti-progestagenic activities and TrOCs were detected in multiple water samples. Several active pharmaceutical ingredients (APIs), industrial compounds, pesticides and other endocrine active compounds were detected in fish carcasses at all sites, ranging from < 4–4700 ng/g wet weight, including the two undeveloped sites. While vitellogenin protein was slightly increased in fish from two of the six sites, the presence of micropollutants did not cause overt sexual endocrine disruption in mosquitofish (i.e., no abnormal gonads or gonopodia). A correlation between lipid accumulation in the liver with total body burden warrants further investigation to determine if exposure to low concentrations of TrOCs can affect fish health and increase stress on organs such as the liver and kidneys via other mechanisms, including disruption of non-sexual endocrine axes involved in lipid regulation and metabolism
Superconductivity in the SU(N) Anderson Lattice at U=\infty
We present a mean-field study of superconductivity in a generalized N-channel
cubic Anderson lattice at U=\infty taking into account the effect of a
nearest-neighbor attraction J. The condition U=\infty is implemented within the
slave-boson formalism considering the slave bosons to be condensed. We consider
the -level occupancy ranging from the mixed valence regime to the Kondo
limit and study the dependence of the critical temperature on the various model
parameters for each of three possible Cooper pairing symmetries (extended s,
d-wave and p-wave pairing) and find interesting crossovers. It is found that
the d- and p- wave order parameters have, in general, very similar critical
temperatures. The extended s-wave pairing seems to be relatively more stable
for electronic densities per channel close to one and for large values of the
superconducting interaction J.Comment: Seven Figures; one appendix. Accepted for publication in Phys. Rev.
Auxiliary particle theory of threshold singularities in photoemission and X-ray absorption spectra: Test of a conserving T-matrix approximation
We calculate the exponents of the threshold singularities in the
photoemission spectrum of a deep core hole and its X-ray absorption spectrum in
the framework of a systematic many-body theory of slave bosons and
pseudofermions (for the empty and occupied core level). In this representation,
photoemission and X-ray absorption can be understood on the same footing; no
distinction between orthogonality catastrophe and excitonic effects is
necessary. We apply the conserving slave particle T-matrix approximation
(CTMA), recently developed to describe both Fermi and non-Fermi liquid behavior
systems with strong local correlations, to the X-ray problem as a test case.
The numerical results for both photoemission and X-ray absorption are found to
be in agreement with the exact infrared powerlaw behavior in the weak as well
as in the strong coupling regions. We point out a close relation of the CTMA
with the parquet equation approach of Nozi{\`e}res et al.Comment: 10 pages, 9 figures, published versio
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