1,200 research outputs found
The supersymmetric configurations of N=2, d=4 supergravity coupled to vector supermultiplets
We classify all the supersymmetric configurations of ungauged N=2,d=4
supergravity coupled to n vector multiplets and determine under which
conditions they are also classical solutions of the equations of motion. The
supersymmetric configurations fall into two classes, depending on the timelike
or null nature of the Killing vector constructed from Killing spinor bilinears.
The timelike class configurations are essentially the ones found by Behrndt,
Luest and Sabra, which exhaust this class and are the ones that include
supersymmetric black holes. The null class configurations include pp-waves and
cosmic strings.Comment: 44 pages, some references adde
Broad diversity of fungi in Hospital Water
Introduction. Some studies have reported the occurrence of microorganisms isolated from water. Considering these microorganisms, fungi are known to occur ubiquitously in the environment, including water, and some are pathogenic and may cause health problems, especially in immunocompromised individuals. The aim of this study was to identify fungi in hospital water samples and to correlate their presence with the concentration of free residual chlorine. Methods. Water samples (100 mL) were collected from taps (n = 74) and water purifiers (n = 14) in different locations in a university hospital. Samples were filtered through a nitrocellulose membrane and placed on Sabouraud dextrose agar and incubated for 24 hours at 30°C. Fungi were identified according to established methods based on macroscopic and microscopic characteristics (filamentous) and physiological tests (yeasts). Free chlorine residual content was measured at the time of sample collection. Results. Seventy species of fungi were identified in the water samples and about 56% of the water samples contained culturable fungi. Cladosporium oxysporum, Penicillium spinulosum, and Aspergillus fumigatus were the most common filamentous fungi. Aureobasidium pullulans and Candida parapsilosis were the most common yeasts. Chemical analyses revealed that free residual chlorine was present in 81.8% of the samples within recommended concentrations. Among samples from water purifiers, 92.9% showed low levels of free residual chlorine (<0.2 mg/L). There was no significant association between chlorine concentrations (either within or outside the recommended range) and the presence of filamentous fungi and yeasts. Conclusions. This study showed that hospital water can be a reservoir for fungi, some of which are potentially harmful to immunocompromised patients. Free residual chlorine was ineffective in some samples.publishersversionpublishe
"I am your mother and your father!": In vitro derived gametes and the ethics of solo reproduction
In this paper, we will discuss the prospect of human reproduction achieved with gametes originating from only one person. According to statements by a minority of scientists working on the generation of gametes in vitro, it may become possible to create eggs from menâs non-reproductive cells and sperm from womenâs. This would enable, at least in principle, the creation of an embryo from cells obtained from only one individual: âsolo reproductionâ. We will consider what might motivate people to reproduce in this way, and the implications that solo reproduction might have for ethics and policy. We suggest that such an innovation is unlikely to revolutionise reproduction and parenting. Indeed, in some respects it is less revolutionary than in vitro fertilisation as a whole. Furthermore, we show that solo reproduction with in vitro created gametes is not necessarily any more ethically problematic than gamete donationâand probably less so. Where appropriate, we draw parallels with the debate surrounding reproductive cloning. We note that solo reproduction may serve to perpetuate reductive geneticised accounts of reproduction, and that this may indeed be ethically questionable. However, in this it is not unique among other technologies of assisted reproduction, many of which focus on genetic transmission. It is for this reason that a ban on solo reproduction might be inconsistent with continuing to permit other kinds of reproduction that also bear the potential to strengthen attachment to a geneticised account of reproduction. Our claim is that there are at least as good reasons to pursue research towards enabling solo reproduction, and eventually to introduce solo reproduction as an option for fertility treatment, as there are to do so for other infertility related purposes
Formulação de uma estratégia de produção em uma fåbrica de sorvetes com enfoque em anålise de desempenho
O seguinte artigo aborda a aplicação dos conceitos de estratĂ©gia de produção em uma organização, bem como sua interface com a gestĂŁo de processos. EstratĂ©gia de Produção Ă© uma forma de definir diretrizes de acordo com os objetivos de desempenho. E a GestĂŁo de Processos mostra-se como uma ferramenta para mapear e facilitar a visualização de aspectos ligados a critĂ©rios competitivos empresariais. Este artigo objetiva mostrar de que forma a matriz importĂąncia-desempenho direciona a estratĂ©gia de produção de uma organização. A empresa em estudo possui problemas relacionados Ă atividade ambulante e Ă entrega de sorvetes em seus pontos de venda; e, com base nessas duas carĂȘncias, foi desenvolvido um estudo de caso e anĂĄlises qualitativas, a partir de visitas Ă empresa, pesquisas bibliogrĂĄficas e tratamentos estatĂsticos - este Ășltimo foi pautado na anĂĄlise de importĂąncia e desempenho dos critĂ©rios competitivos organizacionais selecionados a partir de um planejamento estratĂ©gico. Dessa forma, obteve-se uma estratĂ©gia de produção voltada para os aspectos crĂticos relacionados aos problemas da empresa, permitindo Ă mesma, o aumento das vendas ambulantes e a diferenciação dos nichos de mercado do setor de sorvetes. Assim, a estratĂ©gia elaborada aumentou a adaptabilidade da organização frente ao mercado, orientando-a a seus clientes
Opposite-side flavour tagging of B mesons at the LHCb experiment
The calibration and performance of the oppositeside
flavour tagging algorithms used for the measurements
of time-dependent asymmetries at the LHCb experiment
are described. The algorithms have been developed using
simulated events and optimized and calibrated with
B
+ âJ/ÏK
+, B0 âJ/ÏK
â0 and B0 âD
ââ
Ό
+
ΜΌ decay
modes with 0.37 fbâ1 of data collected in pp collisions
at
â
s = 7 TeV during the 2011 physics run. The oppositeside
tagging power is determined in the B
+ â J/ÏK
+
channel to be (2.10 ± 0.08 ± 0.24) %, where the first uncertainty
is statistical and the second is systematic
Measurement of the branching fraction
The branching fraction is measured in a data sample
corresponding to 0.41 of integrated luminosity collected with the LHCb
detector at the LHC. This channel is sensitive to the penguin contributions
affecting the sin2 measurement from The
time-integrated branching fraction is measured to be . This is the most precise measurement to
date
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