Testing reflection features in 4U 1705-44 with XMM-Newton, BeppoSAX and RXTE in the hard and soft state

We use data of the bright atoll source 4U 1705-44 taken with XMM-Newton, BeppoSAX and RXTE both in the hard and in the soft state to perform a self-consistent study of the reflection component in this source. Although the data from these X-ray observatories are not simultaneous, the spectral decomposition is shown to be consistent among the different observations, when the source flux is similar. We therefore select observations performed at similar flux levels in the hard and soft state in order to study the spectral shape in these two states in a broad band (0.1-200 keV) energy range, with good energy resolution, and using self-consistent reflection models. These reflection models provide a good fit for the X-ray spectrum both in the hard and in the soft state in the whole spectral range. We discuss the differences in the main spectral parameters we find in the hard and the soft state, respectively, providing evidence that the inner radius of the optically thick disk slightly recedes in the hard state.Comment: Accepted for publication in A&A, 20 pages, 12 figure

Mononeuritis multiplex: an uncommon neurological manifestation of cytomegalovirus reactivation in an HIV-infected patient

BACKGROUND: Cytomegalovirus (CMV) reactivation with neurological involvement in patients with acquired immunodeficiency syndrome (AIDS) is increasingly rare since the introduction of antiretroviral therapy (ART). Manifestations include encephalitis, myelitis, polyradiculopathy and, less commonly, mononeuritis multiplex (MNM). We report a case of disseminated CMV disease with gastrointestinal and peripheral and central nervous system involvement in a patient with AIDS, manifesting primarily as MNM. CASE PRESENTATION: A 31-year old woman with AIDS presented with a clinical picture of MNM. Electromyography confirmed the clinical findings. CMV DNA was detected in cerebrospinal fluid (CSF) and blood. Gastrointestinal involvement was histologically documented. HIV RNA was also detected in CSF and brain MRI was consistent with HIV encephalopathy. A diagnosis of disseminated CMV disease (with esophagitis, colitis, encephalitis and MNM) and HIV encephalopathy was made. Treatment consisted of ganciclovir and foscarnet, followed by maintenance therapy with valganciclovir. Evolution was favorable and valganciclovir was stopped after sustained immune recovery following ART initiation. CONCLUSION: We discuss the diagnostic approach to CMV neurological disease, with a focus on MNM and CMV encephalitis. Combination therapy with ganciclovir and foscarnet should be considered for all forms of neurological involvement, although available data are scarce. Since there is significant overlap between CMV encephalitis and HIV encephalopathy, ART drugs with higher CSF penetration may have to be considered. ART and immune recovery are essential to improve outcomes

Umbilical Cord Prolapse In Kaduna, Northern Nigeria: A Study Of Incidence

Prolapse of theumbilical cord is a live threatening obstetric emergency for the fetus-infant. To determine, the incidence of cord prolapse in the hospital. A-12½year retrospective study of all women who presented with cord prolapse in labour at a university teaching hospital. During the period therewere16633 deliveries and 34women presentedwith cord prolapse, giving an incidence of 2.0 per 1000 (1 in 504 deliveries). Highest incidence occurred in women of 35 years and above (5.0 per 1000); in the 25-29 years group 2.3 per 1000 and in those less than 20 years old 1.3 per 1000. The highest incidence of cord prolapse was in the para 5 and over, 2.4 per 1000; para 0, 2.0 per1000 and paras 1 4, 1.9 per 1000.The incidence of cord prolapse in the unregisteredwomenwas 5.2 per 1000, and in the registered 1.5 per 1000. The highest incidence was in the Hausa/ Fulani ethnic group 3.4 per 1000; the Yoruba ethnic group, 2.1 per 1000 ; the Northernminority ethnic group , 2.0 per 1000; the Ibo ethnic group, 1.0 per 1000. No case of cord prolapse was recorded among women of Southern minority ethnic group. The incidence of cord prolapse among preterm births was, 62.7 per 1000, breech, 32.5 per 1000; shoulder, 133.3 per 1000 , twin births.16.8 per 1000 and cesarean births, 11.4 per 1000. Cord prolapse is an uncommon obstetric complication, the incidence of which is determined by the influence of various factors acting individually or in synergy. Keywords: Cord Prolapse, incidence,Kaduna,Nigeria. Nigerian Journal of Clinical Practice Vol. 11 (4) 2008: pp. 316-31

Asymptotic expansions of the solutions of the Cauchy problem for nonlinear parabolic equations

Let $u$ be a solution of the Cauchy problem for the nonlinear parabolic equation $$\partial_t u=\Delta u+F(x,t,u,\nabla u) \quad in \quad{\bf R}^N\times(0,\infty), \quad u(x,0)=\varphi(x)\quad in \quad{\bf R}^N,$$ and assume that the solution $u$ behaves like the Gauss kernel as $t\to\infty$. In this paper, under suitable assumptions of the reaction term $F$ and the initial function $\varphi$, we establish the method of obtaining higher order asymptotic expansions of the solution $u$ as $t\to\infty$. This paper is a generalization of our previous paper, and our arguments are applicable to the large class of nonlinear parabolic equations

Processing and properties of natural fibers reinforced thermoplastic and thermosseting composites

In this work, three different natural fibers were studied and characterized, using optical and SEM microscopy. Woven fabrics of those reinforcement fibers were used to reinforce polyester and epoxy matrices and produce composite plates by vacum lay-up. Also, using an experimental piston blender equipment, long fiber reinforced PLA (LFT) composites were manufactured by hot compression molding. All different obtained composite plates were submitted to mechanical testing in order to determine relevant mechanical proprieties.Fundação para a Ciência e a Tecnologia (FCT

Processing and properties of composites obtained from natural fibres and thermosetting matrices

In this work, different natural fibres were studied and characterized, using optical and SEM microscopy. Those fibres were used to reinforce polyester and epoxy matrices and produce composite plates by hand lay-up. A vacuum bag was then used to allow improving the fibre impregnation, establishing a controlled pressure atmosphere. All different obtained composite plates were submitted to mechanical testing, in order to determine relevant mechanical proprieties. The produced composites were, namely, submitted to flexure and tensile tests, in accordance to ISO 14125 and ISO 527, standards, respectively. It was also determined, for each type of composite, the GIIc property (critical energy release rate in mode II), in order to assess their impact behaviour.Fundação para a Ciência e a Tecnologia (FCT

Burning in the management of heathlands of Erica ciliaris and Erica tetralix: effects on structure and diversity

Can controlled burning be used as a management tool of Erica ciliaris and Erica tetralix wet heathlands? Two E. ciliaris and E. tetralix communities were selected and two 5 x 5 m plots were established in each. These were then characterised on the basis of frequency and cover values and plant species composition. They were subjected to experimental burning, after which the plots were sampled twice a year during the following four and a half years. The results show that the cover of woody species very quickly attained the values of the Control Plots. Diversity and species composition did not suffer notable changes during this period, however, temporal heterogeneity indicates that the main changes occur in the first 18 months of secondary succession. The multivariate analysis showed that the samples registered during this time were grouped as a function of the cover values of the species, which shows that stages exist in the vegetation recovery of these communities. The damage produced by fire in the community is minor, as a rapid recovery of the vegetation was observed, so controlled burning is a useful tool in the management of these heathlands

In search of critical thinking in psychology: an exploration of student and lecturer understandings in higher education

This qualitative study of understandings of critical thinking in higher education aimed to identify themes that could help to demystify critical thinking and inform its more explicit incorporation in the psychology curriculum. Data collected from focus groups with 26 undergraduate psychology students and individual semi-structured interviews with 4 psychology lecturers were examined using thematic analysis. The same key themes were identified from both student and lecturer data: ‘vague beginnings’, ‘conceptualizations’, ‘development and transitions’, and ‘learning strategies’. Both students and lecturers described critical thinking as implicit knowledge that develops through social interactions. The findings indicate the importance of explicit discussion about critical thinking, and could be used to inform the design and delivery of instructional methods to promote critical thinkin