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Binary Ni-B alloys containing varied amounts of titanium were prepared and investigated in this study. Differential Thermal Analysis (DTA) was used to study the solidification and transformation behavior of the alloys, while Optical Microscope (OM) and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray Analyzer (EDXA) were used to study the microstructure of the alloys. Microscopic and thermal investigations of the alloys revealed the presence of two major primary phases Ni (α) and τ with other binary and ternary eutectic structures being present in the hard alloys. The addition of titanium to the Ni-B system enhanced the formation of the ternary phase τ, while solid-state eutectoid transformation of the τ phase was observed in alloys with low titanium composition. But such transformation was not detected in alloys with high titanium contents, which enhanced the formation of hard boride phases. Keywords: Alloy, Thermal Analysis, Microstructure, Eutectoid transformation

During harvesting and storage, microbial pathogens and natural spoilage flora may grow, negatively affecting the composition and texture of oysters and posing a potential health threat to susceptible consumers. A solution to these problems would mitigate associated damaging effects on the seafood industry. The purpose of this study was to investigate the effects of storage temperature on growth of Vibrios as well as other microbial, sensory and textural characteristics of post-harvest shellstock Eastern oysters (Crassostrea virginica). Oysters harvested from the Chesapeake Bay, Maryland, during summer months (June, July, and August, 2010) were subjected to three storage temperatures (5, 10, and 20ºC) over a 10 day period. At selected time intervals (0, 1, 3, 7, 10 days) two separate samples of 6 oysters each were homogenated and analyzed for pH, halophilic plate counts (HPC), total Vibrios, and Vibrio parahaemolyticus (Vp). Oyster meats shucked after storage were also organoleptically evaluated (acceptability, appearance, and odor). Texture analysis was performed using a texture analyzer on meats shucked from oysters held under the same conditions. The pH of the oyster homogenates showed no consistent pattern with storage time and temperature. The HPC (4.5 to 9.4log CFU/g) were highest on day 7 at 20C while olfactory acceptance reduced with time and increasing storage temperatures. The Vp counts increased over time from 3.5 to7.5 log MPN/g by day10. Loss of freshness as judged by appearance and odor was significant over time (p < 0.05). Toughness of oysters increased with storage time at 5 and 10ºC from day 1 to day 3, but was inconsistent after day 7. The results indicate that the length of storage and temperature had a significant effect on bacterial counts and olfactory acceptance of oysters but had an inconsistent effect on texture.

Issues: Quality-management systems (QMS) are uncommon in clinical laboratories in Nigeria, and until recently, none of the nation's 5 349 clinical laboratories have been able to attain the certifications necessary to begin the process of attaining international accreditation. Nigeria's Human Virology Laboratory (HVL), however, began implementation of a QMS in 2006, and in 2008 it was determined that the laboratory conformed to the requirements of ISO 9001:2000 (now 2008), making it the first diagnostic laboratory to be certified in Nigeria. The HVL has now applied for the World Health Organization (WHO) accreditation preparedness scheme. The experience of the QMS implementation process and the lessons learned therein are shared here., Description: In 2005, two personnel from the HVL spent time studying quality systems in a certified clinical laboratory in Dakar, Senegal. Following this peer-to-peer technical assistance, several training sessions were undertaken by HVL staff, a baseline assessment was conducted, and processes were established. The HVL has monitored its quality indicators and conducted internal and external audits; these analyses (from 2007 to 2009) are presented herein., Lessons Learned: Although there was improvement in the pre-analytical and analytical indicators analysed and although data-entry errors decreased in the post-analytical process, the delay in returning laboratory test results increased significantly. There were several factors identified as causes for this delay and all of these have now been addressed except for an identified need for automation of some high-volume assays (currently being negotiated). Internal and external audits showed a trend of increasing non-conformities which could be the result of personnel simply becoming lax over time. Application for laboratory accreditation, however, could provide the renewed vigour needed to correct these non-conformities., Recommendation: This experience shows that sustainability of the QMS at present is a cause for concern. However, the tiered system of accreditation being developed by WHO-Afro may act as a driving force to preserve the spirit of continual improvement., Competing Interests: The authors declare that they have no financial or personal relationship(s) which may have inappropriately influenced them in writing this paper.

Background: Among the countries highly endemic for viral hepatitis, Nigeria is found. Information on how triple infected persons (HIV, HBV, and HCV) fare on HAART in the country is lacking. Laboratory based investigation was carried out to assess the virological and immunological parameters of HIV-1 infected patients co-infected with Hepatitis B and C, accessing care at the Nigerian Institute of Medical Research. It was a case controlled study., Objectives: The study aimed to compare the laboratory data of HIV-HBV-HCV patients seen between 2006 and 2009 with HIV-1 monoinfected patients in the same period, on HAART according to the national guideline and followed up for 12 months., Methods: Detection of Hepatitis B surface Antigen (HBsAg) and Hepatitis C Virus Antibody (HCVAb) were assayed using ELISA techniques (Bio Rad and DIA PRO respectively). The CD4 and HIV viral load were determined using the Cyflow Counter/Kits (Partec) and the Amplicor HIV-1 Monitor Test V1.5 (Roche) techniques respectively., Results: Forty-one (0.4%) of the 10,214 HIV-1 patients seen during the period were co-infected with both HBV and HCV. Over the 12 month-period, median HIV-1 viral load and CD4 count reduced and increased respectively (12,205-200 RNA copies/mL; 210-430 cells/mL from baseline - 12th month), and for the HIV-1 monoinfected patients (36,794-200 RNA copies/mL [p=0.5485] and 206-347 cells/mL [p=0.7703] from baseline - 12th month)., Conclusion: There seems to be no significant influence of hepatitis B and C in HIV infection on HAART judging by the CD4 and viral load profiles which were similar in the two groups.