391 research outputs found
On the equivalence of modes of convergence for log-concave measures
An important theme in recent work in asymptotic geometric analysis is that
many classical implications between different types of geometric or functional
inequalities can be reversed in the presence of convexity assumptions. In this
note, we explore the extent to which different notions of distance between
probability measures are comparable for log-concave distributions. Our results
imply that weak convergence of isotropic log-concave distributions is
equivalent to convergence in total variation, and is further equivalent to
convergence in relative entropy when the limit measure is Gaussian.Comment: v3: Minor tweak in exposition. To appear in GAFA seminar note
Nest use is influenced by the positions of nests and drinkers in aviaries
The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nest
Optimal Concentration of Information Content For Log-Concave Densities
An elementary proof is provided of sharp bounds for the varentropy of random
vectors with log-concave densities, as well as for deviations of the
information content from its mean. These bounds significantly improve on the
bounds obtained by Bobkov and Madiman ({\it Ann. Probab.}, 39(4):1528--1543,
2011).Comment: 15 pages. Changes in v2: Remark 2.5 (due to C. Saroglou) added with
more general sufficient conditions for equality in Theorem 2.3. Also some
minor corrections and added reference
Logarithmically-concave moment measures I
We discuss a certain Riemannian metric, related to the toric Kahler-Einstein
equation, that is associated in a linearly-invariant manner with a given
log-concave measure in R^n. We use this metric in order to bound the second
derivatives of the solution to the toric Kahler-Einstein equation, and in order
to obtain spectral-gap estimates similar to those of Payne and Weinberger.Comment: 27 page
Animal welfare implications of surgical castration and its alternatives in pigs
This paper constitutes a review on the welfare aspects of piglet castration that considers the scientific literature published after 2004. Castrating during the neonatal period (1 to 3 days of age) is clearly painful. In addition, inflammatory processes may take place at the sites of incision, thus adding further pain to the procedure. Surgical castration with general and local anaesthesia, in combination with long-term analgesia, has been shown to reduce pain but the additional handling and injection of the anaesthetic, the effectiveness and limited safety margins have to be thoroughly evaluated. Raising entire males during the whole fattening period or immunocastration of males towards the end of the fattening period are other alternatives with welfare benefits in young pigs compared to current surgical castration, but with some potential welfare drawbacks regarding handling stress and behaviour during fattening. Based on the current knowledge, it can be concluded that sperm sexing and raising entire males after genetic control of boar taint are potentially preferable alternatives to current practices, but need further research, as these methods are not yet availabl
Assessment and management of iatrogenic withdrawal syndrome and delirium in pediatric intensive care units across Europe: an ESPNIC survey.
Analgesia and sedation are essential for the care of children in the pediatric intensive care unit (PICU); however, when prolonged, they may be associated with iatrogenic withdrawal syndrome (IWS) and delirium. We sought to evaluate current practices on IWS and delirium assessment and management (including non-pharmacologic strategies as early mobilization), and to investigate associations between presence of an analgosedation protocol and IWS and delirium monitoring, analgosedation weaning, and early mobilization.
A multicenter cross-sectional survey-based study collecting data from one experienced physician or nurse per PICU in Europe was conducted from January to April 2021. We then investigated differences among PICUs that did or did not follow an analgosedation protocol.
Among 357 PICUs, 215 (60%) responded across 27 countries. IWS was systematically monitored with a validated scale in 62% of PICUs, mostly using the Withdrawal Assessment Tool-1 (53%). Main first-line treatment for IWS was a rescue bolus with interruption of weaning (41%). Delirium was systematically monitored in 58% of PICUs, mostly with the Cornell Assessment of Pediatric Delirium scale (48%) and the Sophia Observation Scale for Pediatric Delirium (34%). Main reported first-line treatment for delirium was dexmedetomidine (45%) or antipsychotic drugs (40%). Seventy-one percent of PICUs reported to follow an analgosedation protocol. Multivariate analyses adjusted for PICU characteristics showed that PICUs using a protocol were significantly more likely to systematically monitor IWS (Odds Ratio [OR ]1.92, 95% Confidence Interval [CI] 1.01-3.67) and delirium (OR 2.00, 95% CI 1.07-3.72), use a protocol for analgosedation weaning (OR 6.38, 95% CI 3.20-12.71), and promote mobilization (OR 3.38, 95% CI 1.63-7.03).
Monitoring and management of IWS and delirium are highly variable among European PICUs. The use of an analgosedation protocol was associated with increased likelihood of monitoring IWS and delirium, performing a structured analgosedation weaning, and promoting mobilization. Education on this topic and interprofessional collaborations are highly needed to help reduce the burden of analgosedation-associated adverse outcomes
Paraoxonase 2 protein is spatially expressed in the human placenta and selectively reduced in labour
Humans parturition involves interaction of hormonal, neurological, mechanical stretch and inflammatory pathways and the placenta plays a crucial role. The paraoxonases (PONs 1â3) protect against oxidative damage and lipid peroxidation, modulation of endoplasmic reticulum stress and regulation of apoptosis. Nothing is known about the role of PON2 in the placenta and labour. Since PON2 plays a role in oxidative stress and inflammation, both features of labour, we hypothesised that placental PON2 expression would alter during labour. PON2 was examined in placentas obtained from women who delivered by cesarean section and were not in labour and compared to the equivalent zone of placentas obtained from women who delivered vaginally following an uncomplicated labour. Samples were obtained from 12 sites within each placenta: 4 equally spaced apart pieces were sampled from the inner, middle and outer placental regions. PON2 expression was investigated by Western blotting and real time PCR. Two PON2 forms, one at 62 kDa and one at 43 kDa were found in all samples. No difference in protein expression of either isoform was found between the three sites in either the labour or non-labour group. At the middle site there was a highly significant decrease in PON2 expression in the labour group when compared to the non-labour group for both the 62 kDa form (p = 0.02) and the 43 kDa form (p = 0.006). No spatial differences were found within placentas at the mRNA level in either labour or non-labour. There was, paradoxically, an increase in PON2 mRNA in the labour group at the middle site only. This is the first report to describe changes in PON2 in the placenta in labour. The physiological and pathological significance of these remains to be elucidated but since PON2 is anti-inflammatory further studies are warranted to understand its role
Associations of neighborhood problems and neighborhood social cohesion with mental health and health behaviors: the Multi-Ethnic Study of Atherosclerosis
Few studies have investigated the specific features implicated in neighborhood-health associations. We examined associations between measures of neighborhood problems and neighborhood social cohesion with depression, smoking, drinking, and walking for exercise in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Neighborhoods were characterized according to participant self-report and aggregated measures based on other MESA participants. Individuals living in the least problematic neighborhoods were significantly less likely to be depressed, to smoke, or to drink. Less socially cohesive neighborhoods were associated with increased depression, smoking, and not walking for exercise. Results persisted after adjusting for individual-level variables. Each measure appeared to capture distinct features of the neighborhood and associations did not differ by race/ethnicity. Results for neighborhood problems were robust to the use of aggregate measures but results for social cohesion generally were not. Future work should determine the health effect of modifying specific features of the neighborhood context.http://deepblue.lib.umich.edu/bitstream/2027.42/60951/1/Assoc of neigh problems & neigh social cohesion MESApdf.pd
Towards a unified theory of Sobolev inequalities
We discuss our work on pointwise inequalities for the gradient which are
connected with the isoperimetric profile associated to a given geometry. We
show how they can be used to unify certain aspects of the theory of Sobolev
inequalities. In particular, we discuss our recent papers on fractional order
inequalities, Coulhon type inequalities, transference and dimensionless
inequalities and our forthcoming work on sharp higher order Sobolev
inequalities that can be obtained by iteration.Comment: 39 pages, made some changes to section 1
Closure properties of solutions to heat inequalities
We prove that if are
sufficiently well-behaved solutions to certain heat inequalities on then
the function given by
also satisfies a heat inequality of a
similar type provided . On
iterating, this result leads to an analogous statement concerning -fold
convolutions. As a corollary, we give a direct heat-flow proof of the sharp
-fold Young convolution inequality and its reverse form.Comment: 12 page
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