No abstract

Influenza epidemic is an important cause of severe illness in the elderly. Age-dependent morbidity of influenza in the elderly is associated with weakened immunity. The baseline age-related memory T cell activity in Chinese persons who are exposed to influenza virus through natural infection, are associated with the protective response to the virus after vaccination, thus providing important pre-vaccination information. A cohort from the general population was established at the end of an influenza season in an area where influenza occurs regularly, and followed for 24 weeks. The subjects had no vaccination history for 5 years. Memory T cell responses were evaluated using a set of peptides spanning the influenza A (H3N2) entire proteome in a gamma interferon (IFN-gamma)-enzyme-linked immunospot (ELISPOT) assay, prior to the next influenza season. Changes of hemagglutination inhibition (HI) antibody titers were also evaluated. IFN-gamma(+) T cell responses against influenza peptides were significantly lower in subjects of 60 years and older. Although the age-related decline of cellular immune response was clear, no significant association of antibody titers with age was found. The pre-vaccination baseline of memory IFN-gamma(+) T cell immunity state in elderly Chinese was significantly lower than in people younger than 60 years. Measurement of the ex vivo cellular immune responses to influenza should be incorporated into the evaluation of protective immunity in elderly persons.

No abstract

In the infrared target detection, the size of structural element tend to be set as pre-determined size, when using the traditional morphological filter based on Top-Hat transform for suppressing the background of the digital infrared image. However, if the target size is unknown or keep changing in the successive frames, the fixed size of the structural element can not meet the detection requirement. To address this issue, we use both Top-Hat Transform and Ostu threshold segmentation algorithm. When the size of structural element is changing continuously, we obtain the different detection results. By analyzing the entropies of the different detection images, a new infrared target detection method was adopted based on the entropy of the detection image. The experimental results prove that this approach can find the best size of structural element, and well detect the target.