254 research outputs found
Age, Growth, Life History, and Fisheries of the Sand Sole, Psettichthys melanostictus
Sand sole, Psettichthys melanostictus, is a small but important part of the west coast groundfish fishery. It has
never been assessed and there is a limited amount of biological data for the species. We provide the first estimates of age and growth for California populations and compare them with studies from other areas. We found that sand sole is a rapidly growing species which may show a strong latitudinal gradient in growth rate. We also found evidence of a recent, strong cohortrelated shift in the sex ratio of the population towards fewer females. In addition
we examined data from the Washington, Oregon, and California commercial fishery to make an initial determination of population status. We found that catch per unit of effort in commercial trawls experienced a decline over time but has rebounded in recent years, except central California (the southern part of its commercial range),
where the decline has not reversed
Career self: a longitudinal study with college students
O self de carreira constituí um subconjunto organizado do universo cognitivo de uma pessoa, responsável pelo carácter subjetivo que a mesma confere à carreira. Este estudo pretende avaliar mudanças no conteúdo do self de carreira
de estudantes universitários, do início para o final do último ano de graduação. Para tal, recorreu-se a medidas repetidas dos
índices da Grelha de Repertório da Carreira (Silva & Taveira, 2005; Silva, 2008). Na investigação, participaram 80 estudantes, dos quais 49 são mulheres (61,25%) e 31 são homens (38,75%), com idades entre os 21 e os 45 anos (M= 23,9, DP= 4,31).
Os resultados indicam que, no final da licenciatura, os estudantes diminuem a distância como se constrõem em relação aos outros e mantêm uma construção positiva do self de carreira.Fundação para a Ciência e a Tecnologia (FCT
The Core Apoptotic Executioner Proteins CED-3 and CED-4 Promote Initiation of Neuronal Regeneration in Caenorhabditis elegans
Laser severing of individual axons in the nematode Caenorhabditis elegans revealed that the apoptotic executioner caspase CED-3 and its regulator CED-4/Apaf-1 play an unexpected beneficial role in promoting axonal regeneration
Determination of the number of light neutrino species from single photon production at LEP
A determination of the number of light neutrino families performed by measuring the cross section of single photon production in \ee\ collision near the \Zo\ resonance is reported. From an integrated luminosity of , collected during the years 1991--94, we have observed 2091 single photon candidates with an energy above 1~\GeV\ in the polar angular region . From a maximum likelihood fit to the single photon cross section, the \Zo\ decay width into invisible particles is measured to be \Ginv = 498 \pm 12 \mathrm{(stat)} \pm 12 \mathrm{(sys)~MeV}. Using the Standard Model couplings of neutrinos to the \Zo, the number of light neutrino species is determined to be $N_\nu = 2.98 \pm 0.07 (\mathrm{stat}) \pm 0.07 (\mathrm{sys}).
Measurement of the average lifetime of b-hadrons in Z decays
We present a measurement of the average b-hadron lifetime at the collider LEP. Using hadronic Z decays collected in the period from 1991 to 1994, two independent analyses have been performed. In the first one, the b-decay position is reconstructed as a secondary vertex of hadronic b-decay particles. The second analysis is an updated measurement of using the impact parameter of leptons with high momentum and high transverse momentum. The combined result is \begin{center} . \end{center} In addition, we measure the average charged b-decay multiplicity and the normalized average b-energy at LEP to be \begin{center} , \end{center} \begin{center} \end{center
Search for neutral B meson decays to two charged leptons
The decays are searched for in 3.5 million hadronic events, which constitute the full LEP I data sample collected by the L3 detector. No signals are observed, therefore upper limits at the 90\%(95\%) confidence levels are set on the following branching fractions: % \begin{center}% {\setlength{\tabcolsep}{2pt} \begin{tabular}{lccccclcccc}% % Br & & & & ; & \hspace*{5mm} & Br & & & & ; \\% Br & & & & ; & \hspace*{5mm} & Br & & & & ; \\% Br & & & & ; & \hspace*{5mm} & Br & & & & . \\% % \end{tabular}% } \end{center}% % The results for and are the first limits set on these decay modes
Measurement of formation in two-photon collisions at LEP1
The formation of the eta' in the reaction ee->ee eta'->ee pi pi gamma has been measured by the L3 detector at a centre-of-mass energy of 91 GeV. The radiative width of the eta' has been found to be 4.17 +/- 0.10(stat.) +/- 0.27(sys.) keV . The Q^2 dependence of the eta' formation cross section has been measured for Q^2 < 10 GeV^2 and the eta' electromagnetic transition form factor has been determined. The form factor can be parametrised by a pole form with Lambda = 0.900 +/- 0.046(stat) +/- 0.022(sys) GeV. It is also consistent with recent non-perturbative QCD calculations
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