On the mass‐to‐light ratios of fossil groups. Are they simply dark clusters?

Defined as X‐ray bright galaxy groups with large differences between the luminosities of their brightest and second brightest galaxies, ‘fossil groups’ are believed to be some of the oldest galaxy systems in the Universe. They have therefore been the subject of much recent research. In this work we present a study of 10 fossil group candidates with an average of 33 spectroscopically confirmed members per group, making this the deepest study of its type to date. We also use these data to perform an analysis of the luminosity function of our sample of fossil groups. We confirm the high masses previously reported for many of fossil systems, finding values more similar to those of clusters than of groups. We also confirm the high dynamical mass‐to‐light ratios reported in many previous studies. While our results are consistent with previous studies in many ways, our interpretation is not. This is because we show that, while the luminosities of the bright central galaxies (BCGs) in these systems are consistent with their high dynamical masses, their richnesses (total number of galaxies above some canonical value) are extremely low. This leads us to suggest a new interpretation of fossil systems in which the large differences between the luminosities of their brightest and second brightest galaxies are simply the result of the high BCG luminosities and low richnesses, while the high masses and low richnesses also explain the high mass‐to‐light ratios. Our results therefore suggest that fossil systems can be characterized as cluster‐like in their masses and BCG luminosities, but possessing the richnesses and optical luminosities of relatively poor groups. These findings are not predicted by any of the current models for the formation of fossil groups. Therefore, if this picture is confirmed, current ideas about the formation and evolution of fossil systems will need to be reformulated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/89559/1/j.1365-2966.2011.19625.x.pd

The effects of nitrogen and light levels on carbohydrate and nitrogen contents in Phaseolus vulgaris

Os efeitos da combinação de três níveis de radiação solar incidente (30%, 70% e 100%) e de três doses de nitrogênio (0, 30 e 60 kg/ha de N) sobre os teores de carboidratos solúveis totais, amido e nitrogênio foram estudados em plantas de Phaseolus vulgaris L. cv. Negrito 897, em condições de campo, durante todo o ciclo da cultura. O aumento da densidade do fluxo luminoso e o das doses de nitrogênio promoveram um incremento nos teores de carboidratos e nitrogênio nos diversos órgãos da planta, sendo os valores máximos observados aos níveis de 70% e 100% de radiação solar e a 30 e 60 kg/ha de N. A 30% de radiação solar incidente e a 30 e 60 kg/ha de N, ocorreu uma redução mais acentuada nos teores dos compostos estudados nas diversas partes da planta, enquanto no tratamento ao qual não se adicionou nitrogênio, independentemente dos níveis de radiação solar, obtiveram-se, também, baixos teores de carboidratos e nitrogênio. Em todos os tratamentos, o acúmulo de nitrogênio total, nas partes da planta, foi proporcional à produção de matéria seca. Observou-se estreita correlação entre o teor de nitrogênio nas folhas, no início da floração, e o número de vagens, na maturação. O maior acúmulo de carboidratos e nitrogênio nas sementes no período de maturidade fisiológica, nos níveis de 70% e 100% de radiação e a 30 e 60 kg/ha de N, deveu-se, principalmente, à fotossíntese e mobilização de assimilados do tecido foliar durante o enchimento de grãos, bem como à mobilização de assimilados armazenados nos caules e raízes durante a fase vegetativa. The effects of three light levels (30%, 70% and 100% of incident sunlight) combined with three nitrogen doses (0, 30 and 60 kg/ha of N) on total soluble carbohydrate, starch and nitrogen contents were studied in Phaseolus vulgaris L. cv. Negrito 897, grown under field conditions, during the entire cycle of the crop. The carbohydrate and nitrogen contents in the plant parts increased with the increase of the light and nitrogen levels. Maxima values are observed under 70% and 100% of sunlight combined with 30 and 60 kg/ha of N. A sharp reduction on carbohydrate and nitrogen contents was observed in all plant parts, caused by the lowest light level associated with high nitrogen levels (30 and 60 kg/ha of N). Lower carbohydrate and nitrogen contents were obtained by no nitrogen addition, independently of light levels. The total nitrogen contents in the plant organs was proportional to dry matter production. A close correlation between leaf nitrogen content at onset of the flowering stage and number of pods at maturation was found. The high accumulation of carbohydrate and nitrogen in the seeds caused by high nitrogen and light levels was due mainly to photosynthesis and assimilate mobilization of leaf tissues during grain filling, as well as mobilization of assimilate stored in stems and roots during the vegetative phase.

Development and assimilate partition in Phaseolus vulgaris as a function of three light levels and three nitrogen doses

O crescimento, a morfologia, a partição de assimilados e a produção de matéria seca foram estudados em Phaseolus vulgaris L. cv. Negrito 897, em condições de campo, sob três níveis de radiação solar (100%, 70% e 30%) e três doses de nitrogênio (zero, 30 e 60 kg de N/ha). A variação da densidade do fluxo radiante e das doses de nitrogênio induziu a planta a modificar a distribuição dos seus fotoassimilados, alterando, consequentemente, seu crescimento e morfologia. A redução da radiação solar e o incremento das doses de nitrogênio promoveram o aumento da altura e da área foliar das plantas. O aumento da razão parte aérea e sistema radicular promovida pelo sombreamento, associado com o incremento das doses de nitrogênio, alterou a partição de assimilados entre os órgãos, resultando em menor proporção de assimilados nas raízes. A ordem sequencial dos drenos metabólicos preferenciais, no entanto, não foi alterada pelos níveis de luz e doses de nitrogênio. A diminuição da radiação solar incidente e das doses de nitrogênio reduziu as taxas de acúmulo de matéria seca na planta toda e em suas partes. Observou-se uma interação significativa entre luz e nitrogênio, em relação ao número de sementes, sendo o maior número alcançado ao nível de 100% de radiação associado com 60 kg de N/ha. A redução da densidade do fluxo radiante promoveu uma diminuição na temperatura da copa das plantas, o que, possivelmente, retardou a senescência de órgãos das plantas sombreadas. Growth, morphology, assimilate partition and dry matter production were studied in Phaseolus vulgaris L. cv. Negrito 897, under field conditions, at three light levels (30%, 70% and 100% of sunlight) and three nitrogen doses (zero, 30 and 60 kg of N/ha). Light flux densities and nitrogen levels induced modifications on the pattern of assimilate distribution, changing the growth and morphology of the plant. Solar energy reduction associated to an increase in nitrogen levels increased stem elongation and leaf area. Shoot/root ratio increased with shading and/or increment of nitrogen levels, changing the normal assimilate partition among organs, and proportionally, less amount of assimilate was exported to roots. However, the preferential sink sequence was not changed by treatments. The rate of dry matter production of the whole plant and its parts decreased with decreasing nitrogen levels and/or shading. A significant interaction between light and nitrogen on one hand and number and dry weight of the seeds on the other was observed. Reduction in light levels decreased the shoot temperature and, probably, delayed the senescence of the plant parts as a consequence of shading.

Dissecting EPPIN protease inhibitor domains in sperm motility and fertilizing ability: Repercussions for male contraceptive development

EPPIN (epididymal protease inhibitor) is a mammalian conserved sperm-binding protein displaying an N-terminal WFDC (whey-acidic protein four-disulfide core) and a C-terminal Kunitz protease inhibitor domains. EPPIN plays a key role in regulating sperm motility after ejaculation via interaction with the seminal plasma protein SEMG1 (semenogelin-1). EPPIN ligands targeting the SEMG1 binding site in the Kunitz domain are under development as male contraceptive drugs. Nevertheless, the relative contributions of EPPIN WFDC and Kunitz domains to sperm function remain obscure. Here, we evaluated the effects of antibodies targeting specific epitopes in EPPIN's WFDC (Q20E antibody, Gln20-Glu39 epitope) and Kunitz (S21C and F21C antibodies, Ser103-Cys123 and Phe90-C110 epitopes, respectively) domains on mouse sperm motility and fertilizing ability. Computer-assisted sperm analysis showed that sperm co-incubation with S21C antibody (but not F21C antibody) lowered progressive and hyperactivated motilities and impaired kinematic parameters describing progressive (straight-line velocity; VSL, average path velocity; VAP and straightness; STR) and vigorous sperm movements (curvilinear velocity; VCL, amplitude of lateral head movement; ALH, and linearity; LIN) compared with control. Conversely, Q20E antibody-induced milder inhibition of progressive motility and kinematic parameters (VAP, VCL and ALH). Sperm co-incubation with S21C or Q20E antibodies affected in vitro fertilization as revealed by reduced cleavage rates, albeit without changes in capacitation-induced tyrosine phosphorylation. In conclusion, we show that targeting specific epitopes in EPPIN Kunitz and WFDC domains inhibits sperm motility and capacitation-associated events, which decrease their fertilizing ability; nevertheless, similar observations in vivo remain to be demonstrated. Simultaneously targeting residues in S21C and Q20E epitopes is a promising approach for the rational design of EPPIN-based ligands with spermostatic activity.Fil: Silva, Alan A. S.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Raimundo, Tamiris R. F.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Mariani, Noemia A. P.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Kushima, Hélio. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Avellar, Maria Christina W.. Universidade Federal de Sao Paulo; BrasilFil: Buffone, Mariano Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Paula Lopes, Fabíola F.. Universidade Federal de Sao Paulo; BrasilFil: Moura, Marcelo T.. Universidade Federal de Sao Paulo; BrasilFil: Silva, Erick J. R.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

Assembléias de Formicidae epigéas no entorno do Parque Nacional da Chapada Diamantina, Bahia, Brasil

Ants at four localities were studied in the surroundins of the National Park of Chapada Diamantina, central region of the State of Bahia, Brazil. Vegetation belongs to the Atlantic forest biome (Sazonal Semideciduous Forest), but it is regionally surrounded by other vegetation formations, mainly of the caatinga and altitude field biomes. In each one of the four areas, 50 samples of ants were collected with a Winkler extractor and anoother 50 with pitfall traps. A total of 191 species distributed in 47 genera was found. The Winkler trap was most efficient in species capture. The communities of the two areas closer to the National Park, at Lençois presented greater similarity between themselves and larger species number, perhaps because they had been less used by humans in the last 40 years, than the two other areas studied, situated in farms and more distant to the Park. The comparative analysis of the similarity indices, calculated from the capture results obtained with the pit-fall traps and Winkler extractor, indicates that the two trees made from the results of all four areas are identical. Although this result was unexpected, it shows that whatever the collection method and the fauna segment studied, the relative similarity between series is respected. If this observation is verified under additional experimental conditions and biomes, it indicates that if the purpose is to use ants as bioindicators, several sampling techniques can be indiscriminately used for the comparative evaluation of ant assemblages, even if different strata are sampled for their fauna, with no impact on the conclusions that can be drawn about their characteristics of degradation or conservation.Foram realizadas coletas de Formicidae em quatro localidades situadas no entorno do Parque Nacional da Chapada Diamantina, região central do Estado da Bahia. A vegetação pertence ao bioma Mata Atlântica (Floresta Estacional Semidecidual), mas é regionalmente circundada por outras formações vegetais, sobretudo dos biomas caatinga e campo rupestre. Em cada uma das quatro áreas, foram coletadas 50 amostras de formigas da serapilheira com o extrator de Winkler e outros 50, com armadilhas de tipo pitfall. Foi encontrado um total de 191 espécies, distribuídas em 47 gêneros. A armadilha de Winkler foi a mais eficiente na captura de espécies. As comunidades das duas áreas situadas mais próximas ao Parque Nacional, em Lençóis, foram as que apresentaram maior similaridade entre si e maior número de espécies, talvez porque foram menos utilizadas pelo homem nos últimos 40 anos do que as duas outras áreas estudadas, situadas em fazendas mais distantes do Parque. A análise comparativa dos índices de similaridade, calculados a partir dos resultados das capturas realizadas com as armadilhas pit-fall e extrator de Winkler, indica que os dois agrupamentos relativos às quatro áreas estudadas são estritamente iguais. Apesar de esse resultado ser surpreendente, ele mostra que, qualquer que seja o método de coleta, isto é, o segmento de fauna amostrada, a similitude relativa entre series amostrais é respeitada. Se essa colocação se verificar em outras condições experimentais e outros biomas, ela indica que, em caso de uso das formigas como indicadores biológicos, diversas metodologias de amostragens poderiam ser indiscriminadamente utilizadas na avaliação comparativa de assembléias de Formicidae, mesmo se forem estudados estratos da fauna diferentes, sem prejuízo das conclusões que podem ser retiradas sobre as características de degradação ou de conservação de cada uma

Intake, digestibility and intake behaviour in cattle fed different levels of palm kernel cake

ABSTRACT Objective. The potential use of palm kernel cake was evaluated as a replacement for soybean and corn meal in cattle feed, by investigating their intake, digestibility levels and the intake behaviour of cattle fed diets containing different levels of palm kernel cake concentrate. Materials and methods. The experiment was conducted at the Experimental Farm of the Federal University of Bahia, between August and October 2009. Five crossbred Holstein × Zebu adults, were used. A 5 × 5 Latin square experimental design was used. The animals were fed Tifton-85 Bermudagrass, which made up 65% of their diet, plus one of five different levels of palm kernel cake concentrate (0, 7, 14, 21 and 28%). Results. A linear decrease in dry matter (kg/day) was observed due to the lower palatability and higher fiber content of the palm kernel cake. Neutral detergent fiber intake by the animals showed a quadratic behavior. The coefficients of fractional digestibilities of the analyzed feed, did not differ due to the inclusion of palm kernel cake. The ingestive behavior of the animals was not influenced by the inclusion of palm kernel cake in the diet. Conclusions. Palm kernel cake can be used as an alternative feed supplement in ruminant production systems to reduce feed costs without changes in the studied variables

Clusiaxanthone and tocotrienol Series from Clusia pernambucensis and their antileishmanial activity

Phytochemical analysis of the ethyl acetate extract from the stem bark of Clusia pernambucensis G. Mariz, Clusiaceae, a Brazilian Cerrado species, led to the isolation and full characterization of a new xanthone, 1,7-dihydroxy-2-(3-methyl-2-butenyl)-6',6'-dimethylpyrano(2',3':3,4)xanthone, namely clusiaxanthone. Four previously unreported tocotrienols from this species were also isolated. A derivative was obtained from clusiaxanthone, 1-hydroxy,7-methoxy-2-(3-methyl2-butenyl)-6',6'-dimethylpyrano(2',3':3,4)xanthone (7-O-methylclusiaxanthone), and an additional derivative was obtained from Z- δ -tocotrienoloic acid. The structures of these compounds were established based on data from ¹H and 13C nuclear magnetic resonance (1D and 2D NMR), high resolution electrospray ionization mass spectrometry (HRESIMS) and infrared spectroscopy. The clusiaxanthone and its derivative were able to control macrophage infection by Leishmania (Leishmania) amazonensis amastigotes (IC50 = 66.9 and 57.4 µM, respectively). The cytotoxicity of the compounds was assessed in BALB/c mouse peritoneal macrophages.A análise fitoquímica do extrato acetato de etila da casca do caule de Clusia pernambucensis G. Mariz, Clusiaceae, uma espécie do Cerrado brasileiro, conduziu ao isolamento e caracterização completa de uma nova xantona, 1,7-dihidróxi-2-(3-metil-2-butenil)-6',6'-dimetilpirano(2',3':3,4) xantona, denominada clusiaxantona. Quatro tocotrienóis ainda não relatados nesta espécie também foram isolados. Um derivado foi obtido a partir da clusiaxantona, 1-hidróxi,7-metóxi-2-(3-metil2-butenil)-6',6'-dimetilpirano(2',3':3,4)xantona (7-O-metil-clusiaxantona), e um segundo derivado foi obtido a partir do ácido Z- δ -tocotrienolóico. As estruturas foram estabelecidas com base em dados de ressonância magnética nuclear de ¹H e 13C (NMR 1D e 2D), espectrometria de massa com ionização por electrospray de alta resolução (HRESIMS) e espectroscopia no infravermelho. No controle da infecção de macrófagos com amastigotas de Leishmania (Leishmania) amazonensis, os compostos ativos foram clusiaxantona e seu derivado (CI50 = 66,9 e 57,4 µM, respectivamente). A citotoxicidade dos compostos foi determinada em macrófagos peritoneais de camundongos BALB/c

The relationship between γ Cassiopeiae’s X-ray emission and its circumstellar environment

γ Cas is the prototypical classical Be star and is recently best known for its variable hard X-ray emission. To elucidate the reasons for this emission, we mounted a multiwavelength campaign in 2010 centered around four XMM-Newton observations. The observational techniques included long baseline optical interferometry (LBOI) from two instruments at CHARA, photometry carried out by an automated photometric telescope and Hα observations. Because γ Cas is also known to be in a binary, we measured radial velocities from the Hα line and redetermined its period as 203.55 ± 0.20 days and its eccentricity as near zero. The LBOI observations suggest that the star’s decretion disk was axisymmetric in 2010, has an system inclination angle near 45°, and a larger radius than previously reported. In addition, the Be star began an “outburst” at the beginning of our campaign, made visible by a brightening and reddening of the disk during our campaign and beyond. Our analyses of the new high resolution spectra disclosed many attributes also found from spectra obtained in 2001 (Chandra) and 2004 (XMM-Newton). As well as a dominant hot ( ≈ 14 keV) thermal component, the familiar attributes included: (i) a fluorescent feature of Fe K even stronger than observed at previous times; (ii) strong lines of N VII and Ne XI lines indicative of overabundances; and (iii) a subsolar Fe abundance from K-shell lines but a solar abundance from L-shell ions. We also found that two absorption columns are required to fit the continuum. While the first one maintained its historical average of 1 × 1021 cm-2, the second was very large and doubled to 7.4 × 1023 cm-2 during our X-ray observations. Although we found no clear relation between this column density and orbital phase, it correlates well with the disk brightening and reddening both in the 2010 and earlier observations. Thus, the inference from this study is that much (perhaps all?) of the X-ray emission from this source originates behind matter ejected by γ Cas into our line of sight

Brazilian consensus on guidelines for diagnosis and treatment for restless legs syndrome

The Consensus on restless legs syndrome is an effort of neurologists from several Brazilian states, which tirelessly reviewed the literature of recent years in search of evidence, both in regard to diagnosis and treatment, according to the Oxford Centre for Evidence-based Medicine.Serv Neurol & Neurocirurgia, Passo Fundo, RS, BrazilUniv São Paulo, Fac Med Ribeirao Preto, BR-14049 Ribeirao Preto, SP, BrazilClin Carlos Bacelar, Rio de Janeiro, RJ, BrazilUniversidade Federal de São Paulo, Dept Psicobiol, São Paulo, BrazilHosp Moinhos Vento, BR-90560030 Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Dept Neurol, São Paulo, BrazilHosp Israelita Albert Einstein, São Paulo, BrazilUniv Fed Alagoas, Fac Med, Maceio, AL, BrazilUniv Fed Pernambuco, Recife, PE, BrazilClin Rio Sono, Rio de Janeiro, RJ, BrazilUniv São Paulo, Fac Med, Hosp Clin, São Paulo, BrazilPontificia Univ Catolica Rio Grande do Sul, Porto Alegre, RS, BrazilUniv Brasilia, Fac Med, Brasilia, DF, BrazilHosp Clin Porto Alegre, Porto Alegre, RS, BrazilProSSono Ctr Med Sono, Ribeirao Preto, BrazilUniversidade Federal de São Paulo, Dept Psicobiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurol, São Paulo, BrazilWeb of Scienc