A model is developed to describe the adhesion between deformable fractal surfaces over the mesoscopic realm that covers the familiar range of interest in nanotechnology from atomic dimensions to microns. This model helps us gain a quantitative understanding of the variation of adhesion with surface energy, with microstructure of rough surfaces, and with bulk deformability. The present analysis goes beyond the Gaussian distribution of asperity heights by investigating the influence of the microstructure of self-affine fractal surfaces. Our calculation reveals that orders of magnitude increase in adhesion are possible as the roughness exponent decreases.

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Isoniazid preventive therapy (IPT) is a recommended strategy by World Health Organization (WHO) for prevention of active TB infection in people living with HIV. However, data on feasibility and outcome of IPT in Asia are limited. We conducted a retrospective study of 242 HIV patients in Penang who were commenced on IPT between 2011 and 2014, at two HIV specialist clinics in Penang General Hospital and Seberang Jaya Hospital. We evaluated the outcome of IPT in terms of completion rate, adverse events and incidence of active TB. A total of 193 (81.1%) patients completed 6 months of IPT. Patients receiving concurrent highly active antiretroviral therapy (HAART) had significantly higher IPT completion rate (86.1%) compared to those who were not on HAART (67.7%). Major reasons for non-completion were adverse events (21/45) and defaulting from follow-up (17/45). Forty patients (18%) developed adverse events, including hepatotoxicity (8.56%) and rash (5.41%). The risk factors for hepatotoxicity were Hepatitis B/C co-infection and alanine transaminase above the upper limit of normal at baseline. None of our patients who received IPT developed active TB up to 1 year of follow-up. IPT is feasible and relatively safe. Coadministration of IPT with HAART does not compromise safety or compliance.

Q fever is a zoonotic disease caused by Coxiella Burnetti. In April 2007, Penang hospital notified a case of brucellosis through the syndromic notification which was later confirmed as Q fever. The patient presented with fever for two weeks and a history of handling the abortus of a goat. An epidemiological investigation was initiated to identify source of infection and prevent transmission. Blood samples from farm worker, contacts and animals from affected and neighboring farms were tested for Q fever. The universal precaution practices of the veterinary and laboratory staff were observed, and their blood specimens were taken for Q fever serology. The patient was tested positive IgM and IgG for Q fever. Out of the 49 blood samples from farm workers, and veterinary and laboratory staff, 12 were positive for IgM, two were positive for IgG, seven were positive for both IgM and IgG,  and 67 (27.2%) of the animal farms were positive for Q fever. There were minimal personal protective equipments used by the veterinary staff when handling the animals. There were goats imported from endemic countries. Prior to this outbreak no screening of imported animals for Q fever from endemic countries was instituted. Overall the farms were kept clean and well managed. All the contacts and animals tested positive for Q fever were treated.