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1.
Sensors (Basel) ; 16(8)2016 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-27556464

RESUMO

Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability.

2.
Blood ; 118(13): 3559-69, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21828137

RESUMO

The phenotype of germinal center (GC) B cells includes the unique ability to tolerate rapid proliferation and the mutagenic actions of activation induced cytosine deaminase (AICDA). Given the importance of epigenetic patterning in determining cellular phenotypes, we examined DNA methylation and the role of DNA methyltransferases in the formation of GCs. DNA methylation profiling revealed a marked shift in DNA methylation patterning in GC B cells versus resting/naive B cells. This shift included significant differential methylation of 235 genes, with concordant inverse changes in gene expression affecting most notably genes of the NFkB and MAP kinase signaling pathways. GC B cells were predominantly hypomethylated compared with naive B cells and AICDA binding sites were highly overrepresented among hypomethylated loci. GC B cells also exhibited greater DNA methylation heterogeneity than naive B cells. Among DNA methyltransferases (DNMTs), only DNMT1 was significantly up-regulated in GC B cells. Dnmt1 hypomorphic mice displayed deficient GC formation and treatment of mice with the DNA methyltransferase inhibitor decitabine resulted in failure to form GCs after immune stimulation. Notably, the GC B cells of Dnmt1 hypomorphic animals showed evidence of increased DNA damage, suggesting dual roles for DNMT1 in DNA methylation and double strand DNA break repair.


Assuntos
Linfócitos B/fisiologia , Diferenciação Celular/genética , DNA (Citosina-5-)-Metiltransferases/fisiologia , Metilação de DNA/fisiologia , Centro Germinativo/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Diferenciação Celular/imunologia , Análise por Conglomerados , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , Epigênese Genética/fisiologia , Perfilação da Expressão Gênica , Centro Germinativo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise em Microsséries , Ovinos , Estudos de Validação como Assunto
3.
J Health Commun ; 15(3): 322-33, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20432111

RESUMO

Over the centuries, many pandemics have come and gone, ranging from plagues to the recent waves of influenza, and have left swathes of destruction all over the world. Most recently, a relatively new pandemic, Avian Influenza, has emerged and is resulting in innumerable amounts of damage on a global scale. Already responsible for the deaths of tens of millions of livestock and wild birds, billions of dollars in damages, and hundreds of human deaths, the pandemic has spread through Asia and is continuing its move westward. With new cases being presented in various countries, the continuous loss of animal life, and the increasing vulnerability to the disease of human populations, governments worldwide have begun taking initiatives to prevent the spread, transmission, and deaths resulting from Avian Influenza. In late 2007, the Federal Government of Pakistan created the National Program for the Control and Prevention of Avian Influenza (NPCPAI). Following the completion of two focus group discussions involving 51 women from the Mansehra District, data indicated that with the recent outbreak of such a dangerous disease, many communities were not informed as to how to prevent the spread and transmission of Avian Influenza. As a result of government-sponsored interventions, through the use of training sessions involving the dissemination of all necessary information regarding Avian Influenza, the individuals who had taken part in the training were much more likely than the uninformed groups to be able to spot the disease, prevent its transmission to other livestock, decontaminate infected areas, and prevent contraction of the disease by themselves and their families. As a result of the success of this program, recommendations for the future include widespread awareness campaigns using mass media resources, training sessions dispersed throughout the regions, and increased funding for current and future projects involving research on prevention and treatment for Avian Influenza.


Assuntos
Surtos de Doenças/prevenção & controle , Virus da Influenza A Subtipo H5N1 , Influenza Humana/prevenção & controle , Animais , Aves , Feminino , Grupos Focais , Educação em Saúde , Humanos , Influenza Aviária/transmissão , Influenza Humana/epidemiologia , Influenza Humana/mortalidade , Paquistão/epidemiologia
4.
Parasit Vectors ; 8: 343, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26108211

RESUMO

BACKGROUND: Molecular studies have suggested that the true diversity of Leucocytozoon (Apicomplexa: Haemospororida) species well exceeds the approximately 35 currently described taxa. Further, the degree of host-specificity may vary substantially among lineages. Parasite distribution can be influenced by the ability of the parasite to infect a host, vector preferences for certain avian hosts, or other factors such as microhabitat requirements that increase the probability that vertebrate hosts and vectors are in frequent contact with each other. Whereas most studies of haemosporidians have focused on passerine hosts, sampling vectors in the same habitats may allow the detection of other lineages affecting other hosts. METHODS: We sampled abundant, ornithophilic black flies (Simuliidae) across a variety of sites and habitats in the Colorado Rocky Mountains throughout the summer of 2007. Black flies were screened with PCR using Leucocytozoon-specific primers that amplify a portion of the cytochrome b gene, and the sequences were compared to the haplotypes in the MalAvi database. Infections of Leucocytozoon from birds sampled in the same area were also included. RESULTS: We recovered 33 unique haplotypes from the black flies in this study area, which represented a large phylogenetic diversity of Leucocytozoon parasites. However, there were no clear patterns of avian host species or geography for the distribution of Leucocytozoon haplotypes in the phylogeny. CONCLUSIONS: Sampling host-seeking vectors is a useful way to obtain a wide variety of avian haemosporidian haplotypes from a given area and may prove useful for understanding the global patterns of host, parasite, and vector associations of these ubiquitous and diverse parasites.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/genética , Haemosporida/isolamento & purificação , Insetos Vetores/parasitologia , Infecções por Protozoários/parasitologia , Simuliidae/parasitologia , Animais , Doenças das Aves/transmissão , Colorado , Citocromos b/genética , Citocromos b/metabolismo , Ecossistema , Feminino , Variação Genética , Haemosporida/classificação , Haemosporida/fisiologia , Haplótipos , Especificidade de Hospedeiro , Masculino , Dados de Sequência Molecular , Filogenia , Infecções por Protozoários/transmissão , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Simuliidae/classificação , Simuliidae/fisiologia
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