577 research outputs found
Vitamin D in pediatric age: consensus of the Italian Pediatric Society and the Italian Society of Preventive and Social Pediatrics, jointly with the Italian Federation of Pediatricians.
Vitamin D plays a pivotal role in the regulation of calcium-phosphorus metabolism, particularly during pediatric age when nutritional rickets and impaired bone mass acquisition may occur.Besides its historical skeletal functions, in the last years it has been demonstrated that vitamin D directly or indirectly regulates up to 1250 genes, playing so-called extraskeletal actions. Indeed, recent data suggest a possible role of vitamin D in the pathogenesis of several pathological conditions, including infectious, allergic and autoimmune diseases. Thus, vitamin D deficiency may affect not only musculoskeletal health but also a potentially wide range of acute and chronic conditions. At present, the prevalence of vitamin D deficiency is high in Italian children and adolescents, and national recommendations on vitamin D supplementation during pediatric age are lacking. An expert panel of the Italian Society of Preventive and Social Pediatrics reviewed available literature focusing on randomized controlled trials of vitamin D supplementation to provide a practical approach to vitamin D supplementation for infants, children and adolescents
Strong Double Higgs Production at the LHC
The hierarchy problem and the electroweak data, together, provide a plausible
motivation for considering a light Higgs emerging as a pseudo-Goldstone boson
from a strongly-coupled sector. In that scenario, the rates for Higgs
production and decay differ significantly from those in the Standard Model.
However, one genuine strong coupling signature is the growth with energy of the
scattering amplitudes among the Goldstone bosons, the longitudinally polarized
vector bosons as well as the Higgs boson itself. The rate for double Higgs
production in vector boson fusion is thus enhanced with respect to its
negligible rate in the SM. We study that reaction in pp collisions, where the
production of two Higgs bosons at high pT is associated with the emission of
two forward jets. We concentrate on the decay mode hh -> WW^(*)WW^(*) and study
the semi-leptonic decay chains of the W's with 2, 3 or 4 leptons in the final
states. While the 3 lepton final states are the most relevant and can lead to a
3 sigma signal significance with 300 fb^{-1} collected at a 14 TeV LHC, the two
same-sign lepton final states provide complementary information. We also
comment on the prospects for improving the detectability of double Higgs
production at the foreseen LHC energy and luminosity upgrades.Comment: 54 pages, 26 figures. v2: typos corrected, a few comments and one
table added. Version published in JHE
SPATIAL ANALYSE OF LITTERFALL IN A GALLERY FOREST
Matas de galeria possuem grande diversidade gen\ue9tica e desempenham
importantes fun\ue7\uf5es ecol\uf3gicas, como a
prote\ue7\ue3o das nascentes, controle da eros\ue3o e funcionam
como filtros retendo poluentes. A serapilheira, que pode ser usada como
um indicativo de produtividade ecol\uf3gica \ue9 amplamente
coletada por meio de coletores que s\ue3o distribu\ueddos
aleatoriamente em um ecossistema florestal. No entanto, a
distribui\ue7\ue3o da vegeta\ue7\ue3o pode apresentar
depend\ueancia espacial, logo, a produtividade da serapilheira pode
ser mapeada utilizando t\ue9cnicas geoestat\uedsticas o que permite
a delimita\ue7\ue3o de zonas de manejo. Portanto, o objetivo deste
estudo foi avaliar a efici\ueancia de m\ue9todos
geoestat\uedsticos na delimita\ue7\ue3o de zonas de manejo da
produtividade de serapilheira em uma \ue1rea de mata de galeria. O
estudo foi realizado na mata de galeria do c\uf3rrego Lava-p\ue9s
(3 ha) em Ipameri - GO, utilizando-se 60 coletores (cada um com 0,33
m\ub2 de \ue1rea e suspensos a 0,65 m do solo) instalados em uma
malha regular georreferenciada de 32 x 32 m. A serapilheira foi
coletada mensalmente de dezembro de 2011 a novembro de 2012. Todas as
amostras foram separadas manualmente nas fra\ue7\uf5es: folhas
(FF), ramos (FR - galhos e cascas), e estruturas reprodutivas (FER -
flores, frutos e sementes) e foram expressas em kg ha-1. Realizou-se a
an\ue1lise estat\uedstica descritiva e geoestat\uedstica dos
dados. A produtividade de serapilheira para a FF e o total apresentou
forte depend\ueancia espacial. A FR e a FER apresentaram efeito
pepita puro. O mapa dos valores de serapilheira total obtido pelo
m\ue9todo de interpola\ue7\ue3o Krigagem indicaram \ue1reas de
produtividade variando de 900 a 10.900 Kg ha-1ano, evidenciando alta
variabilidade na \ue1rea. Foi poss\uedvel por meio da t\ue9cnica
de interpola\ue7\ue3o krigagem delimitar zonas de manejo da
produtividade de serapilheira na mata de galeria estudada, o que
permitiu o manejo florestal espec\uedfico da serapilheira.The gallery forests have great genetic diversity and important
ecological functions, such as protecting the headwaters, controlling
erosion, and functioning as buffer zones and filtering chemicals.
Litterfall, which can be used as an indicator of ecological
productivity, is widely collected using litter traps that are randomly
distributed in a forest plot. However, vegetation distribution may
present spatial dependence, thus the yield of the litterfall can be
mapped using geostatistical techniques allowing the delineation of
management zones. Therefore, the objective of this study was to
evaluate the efficiency of geostatistical methods using the zoning
management productivity of litterfall on a gallery forest in central
Brazil. The study was conducted on the gallery forest along the
\u2018Lava-p\ue9s\u2019 stream in Goi\ue1s State, Brazil where
the experimental site (3 ha) was structured in a grid of 60 litterfall
traps, each of 0.33 m2 held 0.65 m above the ground, georeferenced,
spaced at 32 x 32 m intervals. Litterfall was monthly collected from
December 2011 to November 2012. All litterfall samples were manually
separated into three fractions: leaves (LE), branch bark (BB), and
reproductive parts (RP) and they were expressed in kg ha-1. Statistical
analyses consisted of data description and geostatistics. The
litterfall of for LE and total showed strong spatial dependence. The BB
and RP showed pure nugget effect. The total litterfall maps obtained by
the Kriging interpolation method indicated zones in the map ranging
from 900 to 10,900 kg ha-1 per yr. The kriging interpolation technique
delineate management zones of productivity in the gallery forest
litterfall studied, which allowed the specific forest management of
litterfall
The pharmacological regulation of cellular mitophagy
Small molecules are pharmacological tools of considerable value for dissecting complex biological processes and identifying potential therapeutic interventions. Recently, the cellular quality-control process of mitophagy has attracted considerable research interest; however, the limited availability of suitable chemical probes has restricted our understanding of the molecular mechanisms involved. Current approaches to initiate mitophagy include acute dissipation of the mitochondrial membrane potential (ΔΨm) by mitochondrial uncouplers (for example, FCCP/CCCP) and the use of antimycin A and oligomycin to impair respiration. Both approaches impair mitochondrial homeostasis and therefore limit the scope for dissection of subtle, bioenergy-related regulatory phenomena. Recently, novel mitophagy activators acting independently of the respiration collapse have been reported, offering new opportunities to understand the process and potential for therapeutic exploitation. We have summarized the current status of mitophagy modulators and analyzed the available chemical tools, commenting on their advantages, limitations and current applications
Endoscopic Saphenous harvesting with an Open CO2 System (ESOS) trial for coronary artery bypass grafting surgery: study protocol for a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>In coronary artery bypass grafting surgery, arterial conduits are preferred because of more favourable long-term patency and outcome. Anyway <it>the greater saphenous vein </it>continues to be the most commonly used bypass conduit. <it>Minimally invasive endoscopic saphenous vein harvesting </it>is increasingly being investigated in order to reduce the morbidity associated with conventional open vein harvesting, includes postoperative leg wound complications, pain and patient satisfaction. However, to date the short and the long-term benefits of the endoscopic technique remain controversial. This study provides an interesting opportunity to address this gap in the literature.</p> <p>Methods/Design</p> <p><b>Endoscopic Saphenous harvesting with an Open CO<sub>2 </sub>System </b>trial includes two parallel vein harvesting arms in coronary artery bypass grafting surgery. It is an interventional, single centre, prospective, randomized, safety/efficacy, cost/effectiveness study, in adult patients with elective planned and first isolated coronary artery disease. A simple size of 100 patients for each arm will be required to achieve 80% statistical power, with a significant level of 0.05, for detecting most of the formulated hypotheses. A six-weeks leg wound complications rate was assumed to be 20% in the conventional arm and less of 4% in the endoscopic arm. Previously quoted studies suggest a first-year vein-graft failure rate of about 20% with an annual occlusion rate of 1% to 2% in the first six years, with practically no difference between the endoscopic and conventional approaches. Similarly, the results on event-free survival rates for the two arms have barely a 2-3% gap. Assuming a 10% drop-out rate and a 5% cross-over rate, the goal is to enrol 230 patients from a single Italian cardiac surgery centre.</p> <p>Discussion</p> <p>The goal of this prospective randomized trial is to compare and to test improvement in wound healing, quality of life, safety/efficacy, cost-effectiveness, short and long-term outcomes and vein-graft patency after endoscopic open CO<sub>2 </sub>harvesting system versus conventional vein harvesting.</p> <p>The expected results are of high clinical relevance and will show the safety/efficacy or non-inferiority of one treatment approach in terms of vein harvesting for coronary artery bypass grafting surgery.</p> <p>Trial registration</p> <p>www.clinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01121341">NCT01121341</a>.</p
A lanthanum picrate complex of a 1,2-bisamide substituted calix[4]arene
The synthesis and structural characterization of a lanthanum picrate complex of the proximally-substituted calix[4]arene bisamide, 5,11,17,23-tetra-tert-butyl-25,26- bis(diethylcarbamoylmethoxy)-27,28-dihydroxycalix[4] arene (L), is reported. The complex is formulated as [La(L-H)(picrate)2]2.75CH2Cl2 and crystallises with two inequivalent metal complexes in the unit cell. The differing dispositions of the picrate anions in the two complexes suggest that intramolecular interactions between the aromatic rings of the picrate and calixarene are less significant than the forces involved in the crystal packing of the complexes
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
The indole-3-carbinol cyclic tetrameric derivative CTet inhibits cell proliferation via overexpression of p21/CDKN1A in both estrogen receptor-positive and triple-negative breast cancer cell lines
Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at = 2.76 TeV
The yield of charged particles associated with high- trigger
particles ( GeV/) is measured with the ALICE detector in
Pb-Pb collisions at = 2.76 TeV relative to proton-proton
collisions at the same energy. The conditional per-trigger yields are extracted
from the narrow jet-like correlation peaks in azimuthal di-hadron correlations.
In the 5% most central collisions, we observe that the yield of associated
charged particles with transverse momenta GeV/ on the
away-side drops to about 60% of that observed in pp collisions, while on the
near-side a moderate enhancement of 20-30% is found.Comment: 15 pages, 2 captioned figures, 1 table, authors from page 10,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/350
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