Convex-Concave fitting to successively updated data and its application to covid-19 analysis.

Let measurements of a process be provided sequentially, where the process follows a sigmoid shape, but the data have lost sigmoidicity due to measuring errors. If we smooth the data by making least the sum of squares of errors subject to one sign change in the second divided differences, then we obtain a sigmoid approximation. It is known that the optimal fit of this calculation is composed of two separate sections, one best convex and one best concave.

Salmonella in the tropical household environment--Everyday, everywhere.

Objectives: To determine the prevalence of Salmonella in the environment of case and control houses, and compare serovars isolated from cases and their houses.

Methods: From 2005 to 2008, we tested samples from houses of 0-4 year old cases and community controls in Darwin and Palmerston for Salmonella. Case isolates were compared with environmental isolates.

Pathogenicity of Salmonella strains isolated from egg shells and the layer farm environment in australia.

In Australia, the egg industry is periodically implicated during outbreaks of Salmonella food poisoning. Salmonella enterica serovar Typhimurium and other nontyphoidal Salmonella spp., in particular, are a major concern for Australian public health.

MLVA and phage typing as complementary tools in the epidemiological investigation of Salmonella enterica serovar Typhimurium clusters.

In South Australia serotyping and phage typing are employed for routine Salmonella surveillance. Molecular techniques such as Multiple-locus variable number tandem repeat analysis (MLVA) are increasingly utilized to aid outbreak investigations. During 2007 three Salmonella enterica serovar Typhimurium outbreaks involving phage types DT9, DT29, and DT44 were investigated.

A baseline survey of the microbiological quality of chicken portions and carcasses at retail in two Australian states (2005 to 2006).

Raw poultry products were purchased from the retail market place in two Australian states, New South Wales (n = 549) and South Australia (n = 310). The products sampled on a proportional volume basis were chicken portions with the skin off or skin on, in bulk or tray packs, and whole carcasses. They were collected from butcher shops, supermarkets, and specialty stores from urban areas during the winter (2005) and summer (2006) months.