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Estudou-se o efeito das propriedades físicas e químicas do solo em algumas propriedades da madeira de Tectona grandis oriundas de plantações entre 7 e 15 anos de idade, localizadas nas regiões Norte e Noroeste da Costa Rica, as quais apresentam dois tipos de clima (tropical seco e tropical úmido) e com grande variedade de fertilidade de solo. As análises do solo consistiram no estudo de suas propriedades físicas (porcentagem de argila, limo e areia, densidade aparente, porcentagem de retenção de água e de água útil, retenção 15 Bar e 0,33 Bar) e propriedades químicas (pH, acidez e conteúdo de Ca, Mg, K, P, Zn, Cu, Fe e Mn). As contrações tangenciais e radiais foram as propriedades da madeira mais correlacionadas com as características do solo, seguidas da porcentagem de cerne, medula e casca e teor de umidade na condição verde. A propriedade de menor correlação foi a densidade básica, enquanto a contração volumétrica não foi correlacionada com nenhuma propriedade do solo. Os coeficientes de correlação foram altamente significativos (a = 0,05), embora baixos valores (

We make a theoretical study of $����$ scattering with quantum numbers $J^{PC}=1^{--}$ in a finite box. To calculate physical observables for infinite volume from lattice QCD, the finite box dependence of the potentials is not usually considered. We quantify such effects by means of two different approaches for vector-isovector $����$ scattering based on Unitarized Chiral Perturbation Theory results: the Inverse Amplitude Method and another one based on the $N/D$ method. We take into account finite box effects stemming from higher orders through loops in the crossed $t,u-$channels as well as from the renormalization of the coupling constants. The main conclusion is that for $����$ phase shifts in the isovector channel one can safely apply L��scher based methods for finite box sizes of $L$ greater than $2 m_��^{-1}$., v2: References and acknowledgments added

We review the N_c and m_π dependence of the rho(770) and σ (or f_0(600) resonances generated with the Inverse Amplitude Method. The σ N_c behavior is at odds with being dominantly a q̅q̅ state, but there is a hint of a subdominant q̅q̅o component with a mass above 1 GeV. We find fair agreement with lattice results for the chiral extrapolation of the ρ mass, and that the ρ π π coupling is almost m_π independent whereas the σ π π depends strongly on m_π.

We report on our recent results in the study of the chiral extrapolation of the phase-shifts in elastic pion-pion scattering, using both standard and unitarized ChPT to one and two loops. In the standard ChPT approach, limited to low momenta, we study the S, P and D waves. Unitarization extends the analysis to energies of around 1 GeV, being compatible with standard ChPT at low energies for the S and P waves. We then compare with lattice results and find a good agreement of standard ChPT below p \sim 200 MeV for the I=2, J=0 and I=1, J=1 channels and up to p \sim 500 MeV for the I=2, J=2 channel. Unitarized ChPT improves the agreement in the scalar and vector channels at higher energies. We have also performed a Montecarlo analysis to provide an estimation of the uncertainties., Comment: Proceedings XIV International Conference on Hadron Spectroscopy (hadron2011), 13-17 June 2011, Munich, Germany

We briefly review how light meson resonances are described within one and two-loop Unitarized Chiral Perturbation Theory amplitudes and how, close to Nc=3, light vectors follow the Nc behavior of $q\bar q$ mesons whereas light scalars do not. This supports the hypothesis that the lightest scalar is not predominantly a $q\bar q$ meson, although a subdominant $q\bar q$ component is suggested around 1 GeV at somewhat larger Nc. In contrast, when Nc is very far from 3, like in the Nc --> infinity limit, we explain again in detail why unitarization is not, a priori, reliable nor robust and why this limit should not be used to drag any conclusions about the dominant nature of physical light scalar mesons., Invited talk at the Exicted QCD Meeting. 8-14 February 2009. Zakopane. Poland

We use the one-loop chiral perturbation theory π π -scattering amplitude and dispersion theory in the form of the inverse amplitude method to study the quark-mass dependence of the two lightest resonances of the strong interactions, the f_0(600) (σ) and the ρ meson. As the main results, we find that the rho π π coupling constant is almost quark mass independent and that the ρ mass shows a smooth quark-mass dependence while that of the σ shows a strong nonanalyticity. These findings are important for studies of the meson spectrum on the lattice.

Both scalar and vector light resonances can be generated from the unitarization of one-loop chiral perturbation theory. This amounts to using in a dispersion relation the chiral expansion, which incorporates the correct QCD quark mass dependence. We can thus predict the quark mass dependence of the poles associated to those light resonances. Our results compare well with some recent lattice results for the rho(770) mass and can be used as a benchmark for future lattice results on the rho(770) or the f0(600) also known as the sigma., Comment: To appear in the proceedings of the XII Int. Conf. on Hadron Spectroscopy. HADRON07. Frascati, October, 2007. 8 pages, 3 figures. References added and updated, typos corrected

The heterocyclic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) is a potential human carcinogen found in cooked food that requires initial metabolic activation by cytochrome P450s, primarily CYP1A2. The present study was conducted to examine whether recombinant human CYP1A2 expressed in insect cells mediates the metabolic activation of IQ and whether prenylflavonoids found in hops and beer would modulate the CYP1A2-mediated activation of IQ. The cDNA-expressed human CYP1A2 was found to strongly activate IQ as measured by the Ames Salmonella assay and by the covalent binding of IQ metabolites to calf thymus DNA and protein. Inhibition studies showed that the prenylchalcone xanthohumol and the prenylflavanones 8-prenylnaringenin and isoxanthohumol strongly inhibited the mutagenic activation of IQ mediated by cDNA-expressed human CYP1A2 in the Ames Salmonella assay. The three prenylflavonoids also markedly inhibited the human CYP1A2-mediated binding of IQ to metabolites that bind to DNA. The inhibition of the metabolic activation of IQ was paralleled by the inhibition of acetanilide 4-hydroxylase activity of human CYP1A2. Thus, xanthohumol, isoxanthohumol, and prenylflavanones 8-prenylnaringenin are potent inhibitors of the metabolic activation of IQ and may have the potential to act as chemopreventive agents against cancer induced by heterocyclic amines activated by CYP1A2.

The emulsion copolymerization kinetics of styrene-butyl acrylate was studied in a batch process. The effect of the initiator, emulsifier, chain transfer agent and monomer concentration on copolymerization rate and molecular weight distribution is discussed. Thermal and viscoelastic properties of copolymers were measured. It was found that the n-dodecylthiol introduced into the reactor with the monomers did not affect the copolymerization rate (no redox reaction with the initiator) but the molecular weight was strongly dependent upon its concentration. These two kinetic parameters increase with increasing the butyl acrylate concentration.

Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Mort; Programa d'intervenció Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Muerte; Programa de intervención Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Death; Intervention program Introduction: The coronavirus disease 19 (COVID-19) and its consequences have placed our societies and healthcare systems under pressure. Also, a major impact on the individual and societal experience of death, dying, and bereavement has been observed. Factors such as social distancing, unexpected death or not being able to say goodbye, which might predict Prolonged Grief Disorder (PGD), are taking place. Moreover, hospitals have become a habitual place for End of Life (EOL) situations but not in the usual conditions because, for example, mitigation measures prevent families from being together with hospitalized relatives. Therefore, we implemented an EOL program with a multidisciplinary team involving health social workers (HSW) and clinical psychologists (CP) in coordination with the medical teams and nursing staff. Objectives: We aim to describe an EOL intervention program implemented during COVID-19 in the Vall d'Hebron University Hospital (HUVH). We present its structure, circuit, and functions. Descriptive analyses of the sample and the interventions that required psychological and social attention are reported. Material and methods: The total sample consists of 359 relatives of 219 EOL patients. Inclusion criteria were families cared for during the COVID-19 pandemic with family patients admitted to the HUVH in an EOL situation regardless of whether or not the patient was diagnosed with COVID-19. Results: Our program is based on family EOL care perceptions and the COVID-19 context features that hinder EOL situations. The program attended 219 families, of which 55.3% were COVID-19 patients and 44.7% had other pathologies. The EOL intervention program was activated in most of the EOL situations, specifically, in 85% of cases, and 78% of relatives were able to come and say goodbye to their loved ones. An emotional impact on the EOL team was reported. It is necessary to dignify the EOL situation in the COVID-19 pandemic, and appropriate psychosocial attention is needed to try to minimize future complications in grief processes and mitigate PGD.

The effect of different chilling and gibberellin treatments on growth and development of the peach rootstocks 'Nemaguard' and 'GF305' was studied. A factorial experiment was designed combining cold treatments (0, 5, 15 and 30 days at 4°C temperature) and GA3 concentrations (0, 100 and 200 mg/L). The variables considered were: percentage of germination, number of internodes, plant height and the ratio plant height/number of internodes. Results showed an overall growth increase as a consequence of chilling and gibberellin addition; however the behaviour of the two assayed rootstocks was slightly different. In general terms, 'Nemaguard' responded well to 5 days cold and chilling treatments did not improve growth in a relevant way, whereas 'GF305' showed a more gradual effect of the chilling and gibberellin treatments on the studied parameters. © ISHS 2012.

• Bud dormancy release in many woody perennial plants responds to the seasonal accumulation of chilling stimulus. MADS-box transcription factors encoded by DORMANCY ASSOCIATED MADS-box (DAM) genes in peach (Prunus persica) are implicated in this pathway, but other regulatory factors remain to be identified. In addition, the regulation of DAM gene expression is not well known at the molecular level. • A microarray hybridization approach was performed to identify genes whose expression correlates with the bud dormancy-related behaviour in 10 different peach cultivars. Histone modifications in DAM6 gene were investigated by chromatin immunoprecipitation in two different cultivars. • The expression of DAM4-DAM6 and several genes related to abscisic acid and drought stress response correlated with the dormancy behaviour of peach cultivars. The trimethylation of histone H3 at K27 in the DAM6 promoter, coding region and the second large intron was preceded by a decrease in acetylated H3 and trimethylated H3K4 in the region of translation start, coinciding with repression of DAM6 during dormancy release. • Analysis of chromatin modifications reinforced the role of epigenetic mechanisms in DAM6 regulation and bud dormancy release, and highlighted common features with the vernalization process in Arabidopsis thaliana and cereals. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

To better understand the molecular and physiological mechanisms underlying maintenance and release of seasonal bud dormancy in perennial trees, we identified differentially expressed genes during dormancy progression in reproductive buds from peach (Prunus persica [L.] Batsch) by suppression subtractive hybridization (SSH) and microarray hybridization. Four SSH libraries were constructed, which were respectively enriched in cDNA highly expressed in dormant buds (named DR), in dormancy-released buds (RD) and in the cultivars with different chilling requirement, 'Zincal 5' (ZS) and 'Springlady' (SZ), sampled after dormancy release. About 2500 clones picked from the four libraries were loaded on a glass microarray. Hybridization of microarrays with the final products of SSH procedure was performed in order to validate the selected clones that were effectively enriched in their respective sample. Nearly 400 positive clones were sequenced, which corresponded to 101 different unigenes with diverse functional annotation. We obtained DAM4, 5 and 6 genes coding for MADS-box transcription factors previously related to growth cessation and terminal bud formation in the evergrowing mutant of peach. Several other cDNAs are similar to dormancy factors described in other species, and others have been related to bud dormancy for the first time in this study. Quantitative reverse transcription polymerase chain reaction analysis confirmed differential expression of cDNAs coding for a Zn-finger transcription factor, a GRAS-like regulator, a DNA-binding protein and proteins similar to forisome subunits involved in the reversible occlusion of sieve elements in Fabaceae, among others. © The Author 2010. Published by Oxford University Press. All rights reserved.