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

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

Cancer distribution pattern in south-western Nigeria

 The burden of cancer in Nigeria is appreciable with about 100,000 new cancer cases been reported in the country each year. This study aimed to determine the level of occurrence and pattern of distribution of different cancer types in two major functional cancer registries in south-western Nigeria. A desk review of the level of occurrence and pattern of distribution of different cancer types in Lagos and Ibadan cancer registries over a 5 year period (2005-2009) was carried out. The results obtained showed a total number of 5094 cancer patients registered between 2005 and 2009 in both Lagos (60%) and Ibadan (40%) cancer registries. Breast cancer accounted for the majority of cases (20.2%), followed by cervical cancer (7.9 %), fibroid (4.4%), liver (4.4%), stomach (4.3%), brain (3.9%), pancreas (3.8%), prostate (3.3%), lung (3.0%) and cancer of the kidney (0.7%). There were significant differences (P ≤ 0.05) in the level of occurrence between cancers of the breast, cervix, prostate, liver, ovary and all other cancers. Liver cancer (147; 77) and bone cancer (91; 37) were predominant in females than males while lung cancer (89; 65), stomach cancer (112; 109), and kidney cancer (24; 14) were predominant in males than females. In conclusion the findings of this study provide insights to cancer epidemiology in the western region of Nigeria. This study confirms earlier findings that breast, prostate, liver and cervical cancers account for the majority of cases of cancers in Nigeria. Thus, there is need to organize on a wider scale suitable methods for early detection of these diseases

Development and assessment to environmentally friendly natural fiber composites

Two different types of natural fibers (jute and sisal) were studied and characterized, using optical microscopy, pycnometry density, single filament and linear density tests. Jute fibers were processed into composite parts from woven fabrics raw-material and sisal fibers were also processed into final composite componentes but in the form of chopped mat. Those fibers were used to reinforce polyester and epoxy matrices and therefore produce composite plates by resin infusion molding. Finally, the final obtained composite plates were submitted to mechanical testing, in order to assess their relevant mechanical properties.Fundação para a Ciência e a Tecnologia (FCT

A new hard-particle model for anisotropic fluids

We report a new hard-particle model system consisting of hard cylinders, we have determined the geometrical conditions that let us know whether or not two given cylinders overlap. In addition we have carried out Monte Carlo simulations sampling the canonical ensemble on this system, the numerical results indicate that this system exhibits mesomorphic behaviour

Knowledge, treatment seeking and preventive practices in respect of malaria among patients with HIV at the Lagos University Teaching Hospital

The synergistic interaction between Human Immunodeficiency virus (HIV) disease and Malaria makes it mandatory for patients with HIV to respond appropriately in preventing and treating malaria. Such response will help to control the two diseases. This study assessed the knowledge of 495 patients attending the HIV clinic, in Lagos University Teaching Hospital, Nigeria.  Their treatment seeking, preventive practices with regards to malaria, as well as the impact of socio – demographic / socio - economic status were assessed. Out of these patients, 245 (49.5 %) used insecticide treated bed nets; this practice was not influenced by socio – demographic or socio – economic factors.  However, knowledge of the cause, knowledge of prevention of malaria, appropriate use of antimalarial drugs and seeking treatment from the right source increased with increasing level of education (p < 0.05). A greater proportion of the patients, 321 (64.9 %) utilized hospitals, pharmacy outlets or health centres when they perceived an attack of malaria. Educational intervention may result in these patients seeking treatment from the right place when an attack of malaria fever is perceived