Narrow Results

Microbial pathogens possess a repertoire of virulence determinants that each make unique contributions to fitness during infection. Analysis of these in vivo-expressed functions reveals the biology of the infection process, encompassing the bacterial infection strategies and the host ecological and environmental retaliatory strategies designed to combat them (e.g. thermal, osmotic, oxygen, nutrient and acid stress). Many of the bacterial virulence functions that contribute to a successful infection are normally only expressed during infection. A genetic approach was used to isolate mutants that ectopically expressed many of these functions in a laboratory setting. Lack of DNA adenine methylase (Dam) in Salmonella typhimurium abolishes the preferential expression of many bacterial virulence genes in host tissues. Dam^-Salmonella were proficient in colonization of mucosal sites but were defective in colonization of deeper tissue sites. Additionally, Dam^- mutants were totally avirulent and effective as live vaccines against murine typhoid fever. Since dam is highly conserved in many pathogenic bacteria that cause significant morbidity and mortality worldwide, Dams are potentially excellent targets for both vaccines and antimicrobials.

Trilateral research methods are developed by the author integrating morphology, molecular biology (physiology and biochemistry), and molecular genetics of remodeling by means of biomechanics. Through this research method the author develops artificial bone marrow chamber using bioceramics.

The author discovers through studies on evolution of hemopoiesis that the morphology of an organism can be changed by vicissitudes of inner or outer stimuli of biomechanics, i.e., environmental factors, which act to the organism, and if these vicissitudes of biomechanical stimuli are transmitted to the next generation morphological changes can be transmitted. Through this discovery the use and disuse theory of Lamarck can be explained biomechanically in molecular genetics.

Experimental evolutionary studies are carried out as follows: developing artificial bone marrow biochambers, the author has implanted them into archetype vertebrates as well as mammals, compared them each other, and analyzed them. Developments of hemopoiesis in bone marrow chambers in phylogeny are evident as the action of the gravity in terrestrialization, which is converted into heightening of blood pressure in chondrichthyes. As conclusion use and disuse theory is evidenced in second revolution of vertebrates for the gravity to trigger genetic expression in mesenchymal cells not only producing hemopoiesis conjugated with ossification of the cartilage but inducing major histocompatibility complex (MHC).

In order to solve the problem of high power factor when a low content of harmonic current and the performance index of DC side, the key problem of PWM control strategy was proposed. The theoretical analysis and experimental results proved the feasibility and effectiveness of the PWM controller based on ADRC controller and the experimental results proved the feasibility and effectiveness of the scheme.