Ultrafast Pulse Radiolysis Using a Terawatt Laser Wakefield Accelerator

We report the first ultrafast pulse radiolysis transient absorption spectroscopy measurements from the Terawatt Ultrafast High Field Facility (TUHFF) at Argonne National Laboratory. TUHFF houses a 20 TW Ti:sapphire laser system that generates 2.5 nC sub-picosecond pulses of multi-MeV electrons at 10 Hz using laser wakefield acceleration. The system has been specifically optimized for kinetic measurements in a pump-probe fashion. This requires averaging over many shots which necessitates stable, reliable generation of electron pulses. The latter were used to generate excess electrons in pulse radiolysis of liquid water and concentrated solutions of perchloric acid. The hydronium ions in the acidic solutions react with the hydrated electrons resulting in the rapid decay of the transient absorbance at 800 nm on the picosecond time scale. Time resolution of a few picoseconds has been demonstrated. The current time resolution is determined primarily by the physical dimensions of the sample and the detection sensitivity. Subpicosecond time resolution can be achieved by using thinner samples, more sensitive detection techniques and improved electron beam quality.Comment: submitted to J. Appl. Phys. 5 figures, 23 page

DNA methylation biomarkers of myocardial infarction and cardiovascular disease

Background: The epigenetic landscape underlying cardiovascular disease (CVD) is not completely understood and the clinical value of the identifed biomarkers is still limited. We aimed to identify diferentially methylated loci associ‑ ated with acute myocardial infarction (AMI) and assess their validity as predictive and causal biomarkers. Results: We designed a case-control, two-stage, epigenome-wide association study on AMI (ndiscovery=391, nvalidation=204). DNA methylation was assessed using the Infnium MethylationEPIC BeadChip. We performed a fxed efects meta-analysis of the two samples. 34 CpGs were associated with AMI. Only 12 of them were available in two independent cohort studies (n~1800 and n~2500) with incident coronary and cardiovascular disease (CHD and CVD, respectively). The Infnium HumanMethylation450 BeadChip was used in those two studies. Four of the 12 CpGs were validated in association with incident CHD: AHRR-mapping cg05575921, PTCD2-mapping cg25769469, intergenic cg21566642 and MPO-mapping cg04988978. We then assessed whether methylation risk scores based on those CpGs improved the predictive capacity of the Framingham risk function, but they did not. Finally, we aimed to study the causality of those associations using a Mendelian randomization approach but only one of the CpGs had a genetic infuence and therefore the results were not conclusive. Conclusions: We have identifed 34 CpGs related to AMI. These loci highlight the relevance of smoking, lipid metab‑ olism, and infammation in the biological mechanisms related to AMI. Four were additionally associated with incident CHD and CVD but did not provide additional predictive informatio

Brazilian Propolis: Correlation Between Chemical Composition and Antimicrobial Activity

The chemical composition of ethanol extracts from samples of Brazilian propolis (EEPs) determined by HPLC and their activity against Trypanosoma cruzi, Staphylococcus aureus, Streptococcus pneumoniae, Klebisiella pneumoniae, Candida albicans, Sporothrix schenckii and Paracoccidioides brasiliensis were determined. Based on the predominant botanical origin in the region of samples' collection, the 10 extracts were separated into three groups: A (B. dracunculifolia + Auraucaria spp), B (B. dracunculifolia) and C (Araucaria spp). Analysis by the multiple regression of all the extracts together showed a positive correlation, higher concentrations leading to higher biological effect, of S. aureus with p-coumaric acid (PCUM) and 3-(4-hydroxy-3-(oxo-butenyl)-phenylacrylic acid (DHCA1) and of trypomastigotes of T. cruzi with 3,5-diprenyl-4-hydroxycinnamic acid derivative 4 (DHCA4) and 2,2-dimethyl-6-carboxyethenyl-2H-1-benzopyran (DCBEN). When the same approach was employed for each group, due to the small number of observations, the statistical test gave unreliable results. However, an overall analysis revealed for group A an association of S. aureus with caffeic acid (CAF) and dicaffeoylquinic acid 3 (CAFQ3), of S. pneumoniae with CAFQ3 and monocaffeoylquinic acid 2 (CAFQ2) and of T. cruzi also with CAFQ3. For group B, a higher activity against S. pneumoniae was associated DCBEN and for T. cruzi with CAF. For group C no association was observed between the anitmicrobial effect and any component of the extracts. The present study reinforces the relevance of PCUM and derivatives, especially prenylated ones and also of caffeolyquinic acids, on the biological activity of Brazilian propolis

A Indissociabilidade entre Ensino, Pesquisa e Extensão: um Relato de Experiência da Integração entre a Universidade e a Rede de Atenção Integral à Saúde Mental em Volta Redonda – RJ

O objetivo deste relato partilhar nossa experincia como docentes e alunos do Curso de Psicologia da Universidade Federal Fluminense Volta Redonda, em projetos de extenso desenvolvidos em parceria com a rede de sade mental da regio em que a Universidade est sediada. As atividades desenvolvidas situam-se em torno do tema dos desafios do trabalho em sade mental, considerando trs eixos fundamentais: educao permanente, integrao ensino-servio de sade e indissociabilidade entre ensino, pesquisa e extenso

Optimization of cutoff parameters using DFT periodic calculations for (110) rutile and (101) anatase TiO2 surfaces

O uso do TiO2 como catalisador na conversão de Compostos Orgânicos Voláteis em substâncias menos tóxicas é uma importante aplicação para a melhoria da qualidade de vida do ser humano. Nesse trabalho, foram estudadas as superfícies (110) rutilo e (101) anatase do TiO2. Estas superfícies foram utilizadas para estudos de adsorção de moléculas de benzeno, tolueno, etilbenzeno, o-xileno, m-xileno e p-xileno (BTEX). A Teoria do Funcional de Densidade (DFT) com condições de contorno periódicas e conjunto de funções de base de ondas planas e o funcional de troca e correlação PW91 foram usados. Os resultados mostraram que o uso de 300 eV e 3x3x3 para a energia de corte das ondas planas e a malha de pontos k, respectivamente, foram considerados apropriados para os cálculos da adsorção do BTEX. As supercélulas com quatro camadas (3x2) para a superfície (110) do TiO2 rutilo e (3x1) para a superfície (101) do TiO2 anatase foram usadas para a modelagem da superfície. _______________________________________________________________________________________________ ABSTRACTTiO2 used as a catalyst in the conversion of Volatile Organic Compounds into less toxic substances is an important application for improving the quality of human life. In this work, TiO2 (110) rutile and (101) anatase surfaces were studied. These surfaces were used for benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene (BTEX) molecules adsorption studies. The Density Functional Theory (DFT) with periodic boundary conditions and plane wave basis set with the PW91 exchange-correlation functional were used. The results showed that 300 eV for the cutoff energy of the plane waves and 3x3x3 k points mesh were appropriate for the BTEX adsorption calculation. A supercell with four layers (3x2) for the (110) rutile TiO2, and (3x1) for the (101) anatase TiO2 were considered for the surface modeling

A ausência de mutações no gene PAX6 em três casos de síndrome de Morning Glory associada à deficiência isolada de hormônio do crescimento

Morning glory syndrome (MGS) is a congenital optic disc dysplasia often associated with craniofacial anomalies, especially basal encephalocele and hypopituitarism. Clinical signs are varied and often occult. The PAX6 gene is involved in ocular morphogenesis and is expressed in numerous ocular tissues during development especially in the developing central nervous system. The aim of the present study is to evaluate PAX6 in MGS associated with isolated growth hormone deficiency. Three pre-pubertal males (A, B and C) with MGS and short stature due to growth hormone deficiency, treated with recombinant human growth hormone with limited response, were reported. Two of them had basal encephalocele. Coding and non-coding sequences corresponding of PAX6 different transcripts were analyzed by direct sequencing. Nucleotide variations causing putative aminoacid change were not observed. Patient A presented the new IVS2+9G>A transition, whereas patients A and C were heterozygous for known single nucleotide polymorphisms (SNP) within the intron 4. In addition, two SNP heterozygoses were observed for patient C in both intron 9 and 13. Sequencing also revealed several nucleotide variations in patient B. Two heterozygoses for known polymorphisms were identified along with a novel C>A nucleotide change in intron 4. This patient also presented a low number on the TG repeat in intron 9 and a new IVS11+33A>T transversion. Gene regulation and transcription of PAX6 are complex processes; there are two major protein isoforms, PAX6(-5a) and PAX6(+5a), and nine transcripts described. Furthermore, extra transcription regulatory elements have been postulated within PAX6 introns. Considering that neither population distributions on PAX6 polymorphism nor their linkeages with diseases have been reported, a functional effect due to alterations described here cannot be discarded.A síndrome de Morning Glory (SMG) é uma displasia óptica congênita associada a anomalias craniofaciais, principalmente encefalocele basal e hipopituitarismo. Os sinais clínicos são variados e muitas vezes ocultos. O gene PAX6 está envolvido na morfogênese ocular e se expressa em vários tecidos oculares durante o desenvolvimento do sistema nervoso central. O objetivo deste estudo foi avaliar o gene PAX6 na SMG associada com deficiência isolada de hormônio de crescimento. Foram relatados três pacientes pré-púberes (A, B e C) com SMG e baixa estatura por deficiência de hormônio de crescimento tratados com hormônio de crescimento recombinante humano. As seqüências codificadoras e não-codificadoras correspondentes ao PAX6 em diferentes transcritos foram analisadas por seqüenciamento direto. Variações nucleotídeas com trocas pontuais de aminoácidos não foram encontradas. O paciente A apresentou uma transição nova IVS2+9G>A, enquanto os pacientes A e C foram heterozigotos para um polimorfismo (SNP) no íntron 4. Ainda, dois SNPs em heterozigose nos íntrons 9 e 13 foram observados no paciente C. O seqüenciamento também mostrou várias variações nucleotídeas no paciente B. Dois SNPs conhecidos com a alteração nucleotídea nova C>A no íntron 4 foram observados em heterozigose. Este paciente também apresentou um baixo número de repetições TG no íntron 9 e uma nova transversão IVS11+33A>T. A regulação e a transcrição do gene PAX6 são um processo complexo; existem 2 isoformas principais da proteína, PAX6(-5a) e PAX6(+5a) e 9 transcritos descritos. Considerando que nem a distribuição de SNPs no PAX6 e nem as suas ligações com as doenças foram relatadas, um defeito funcional devido às alterações descritas não pode ser descartado.University of Campinas Faculty of Medical Sciences Pediatric Endocrinology UnitFederal University of São Paulo School of Medicine Pediatric Endocrinology UnitUNIFESP School of Medicine Department of RadiologyUnicamp Center of Molecular Biology and Genetic EngineeringUNIFESP, EPM, Pediatric Endocrinology UnitUNIFESP, School of Medicine Department of RadiologySciEL

The Birth of an Ultra-Luminous X-ray Source in M83

A previously undetected X-ray source (L_X<10**36 erg/s) in the strongly star-forming galaxy M83 entered an ultraluminous state between August 2009 and December 2010. It was first seen with Chandra on 23 December 2010 at L_X ~ 4 10**39 ergs/s, and has remained ultraluminous through our most recent observations in December 2011, with typical flux variation of a factor of two. The spectrum is well fitted by a combination of absorbed power-law and disk black-body models. While the relative contributions of the models varies with time, we have seen no evidence for a canonical state transition. The luminosity and spectral properties are consistent with accretion powered by a black hole with M_BH ~ 40-100 solar masses. In July 2011 we found a luminous, blue optical counterpart which had not been seen in deep HST observations obtained in August 2009. These optical observations suggest that the donor star is a low-mass star undergoing Roche-lobe overflow, and that the blue optical emission seen during the outburst is coming from an irradiated accretion disk. This source shows that ultraluminous X-ray sources (ULXs) with low-mass companions are an important component of the ULX population in star-forming galaxies, and provides further evidence that the blue optical counterparts of some ULXs need not indicate a young, high-mass companion, but rather that they may indicate X-ray reprocessing.Comment: 40 pages, 7 figures, accepted for publication in Ap

Branched-Chain Amino Acids, Alanine, and Thyroid Function:A Cross-Sectional, Nuclear Magnetic Resonance (NMR)-Based Approach from ELSA-Brasil

The association of thyroid function with essential and non-essential amino acids is understudied, despite their common metabolic roles. Thus, our aim was to evaluate the association of thyroid function with the levels of branched-chain amino acids (BCAAs—leucine, isoleucine, and valine) and of alanine in the general population. We utilized data from the São Paulo research center of ELSA-Brasil, a longitudinal population-based cohort study. Thyroid parameters included thyroid stimulating hormone (TSH), free T4 and free T3 levels, and the FT4:FT3 ratio. BCAAs and alanine were analyzed on a fully automated NMR platform. The current analysis included euthyroid participants and participants with subclinical hyperthyroidism and hypothyroidism. We used Pearson’s coefficient to quantify the correlation between thyroid-related parameters and amino acids. Linear regression models were performed to analyze whether thyroid parameters were associated with BCAAs and alanine levels. We included 4098 participants (51.3 ± 9.0 years old, 51.5% women) in this study. In the most adjusted model, higher levels of TSH were associated with higher levels of alanine, FT4 levels were inversely associated with isoleucine levels, FT3 levels were statistically significant and positively associated with valine and leucine, and the T3:T4 ratio was positively associated with all amino acids. We observed that subclinical hypothyroidism was positively associated with isoleucine and alanine levels in all models, even after full adjustment. Our findings highlight the association of subclinical hypothyroidism and thyroid-related parameters (including TSH, free T4, free T3, and FT4:FT3 ratio) with BCAAs and alanine. Further studies are needed to explore the mechanisms underlying this association. These insights contribute to our understanding of the influence of thyroid-related parameters on BCAA and alanine metabolism.</p