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23 papers found.
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Consumer physical activity tracking device ownership and use among a population-based sample of adults

Macridis, Steven Johnson, Jeff K. Vallance. Formal analysis: Jeff K. Vallance. Funding acquisition: Jeff K. Vallance. Project administration: Soultana Macridis, Nora Johnston. Resources: Soultana ... Macridis, Nora Johnston. Supervision: Jeff K. Vallance. Writing ± original draft: Soultana Macridis, Jeff K. Vallance. Writing ± review & editing: Soultana Macridis, Nora Johnston, Steven Johnson, Jeff K

Best strategies to recruit and enroll elderly Blacks into clinical and biomedical research

Best strategies to recruit and enroll elderly Blacks into clinical and biomedical research Lennox A Graham,1 Julius Ngwa,2 Oyonumo Ntekim,3 Oludolapo Ogunlana,4 Saba Wolday,4 Steven Johnson,3 Megan ... Internal Medicine, h oward University Teaching hospital , Washington, DC, UsA , USA PowerdbyTCPDF(ww.tcpdf.org) saba Wolday 4 steven Johnson 3 Background: Historically, Blacks have been disproportionately

A qualitative study examining healthcare managers and providers’ perspectives on participating in primary care implementation research

Background Primary care reforms should be supported by high-quality evidence across the entire life cycle of research. Front-line healthcare providers play an increasing role in implementation research. We recently evaluated two interventions for people with type 2 diabetes (T2D) in partnership with four Primary Care Networks (PCNs) in Alberta, Canada. Here, we report healthcare...

Human pathogens associated with the blacklegged tick Ixodes scapularis: a systematic review

Background The blacklegged tick Ixodes scapularis transmits Borrelia burgdorferi (sensu stricto) in eastern North America; however, the agent of Lyme disease is not the sole pathogen harbored by the blacklegged tick. The blacklegged tick is expanding its range into areas of southern Canada such as Ontario, an area where exposure to blacklegged tick bites and tick-borne pathogens...

Osteoarthritis prevalence and modifiable factors: a population study

Background This study’s objectives were to investigate the prevalence of self-reported knee and hip osteoarthritis (OA) stratified by age and sex and to examine the association of modifiable factors with knee and hip OA prevalence. The study was conducted using randomly sampled data gathered from four communities in the province of Alberta, Canada. Methods A large adult...

Alternation as a form of allocation for quality improvement studies in primary healthcare settings: the on-off study design

Background Randomized controlled trials are considered the “gold standard” for scientific rigor in the assessment of benefits and harms of interventions in healthcare. They may not always be feasible, however, when evaluating quality improvement interventions in real-world healthcare settings. Non-randomized controlled trials (NCTs) are designed to answer questions of...

Coral Reef Disturbance and Recovery Dynamics Differ across Gradients of Localized Stressors in the Mariana Islands

The individual contribution of natural disturbances, localized stressors, and environmental regimes upon longer-term reef dynamics remains poorly resolved for many locales despite its significance for management. This study examined coral reefs in the Commonwealth of the Northern Mariana Islands across a 12-year period that included elevated Crown-of-Thorns Starfish densities...

The homo-oligomerisation of both Sas-6 and Ana2 is required for efficient centriole assembly in flies

Sas-6 and Ana2/STIL proteins are required for centriole duplication and the homo-oligomerisation properties of Sas-6 help establish the ninefold symmetry of the central cartwheel that initiates centriole assembly. Ana2/STIL proteins are poorly conserved, but they all contain a predicted Central Coiled-Coil Domain (CCCD). Here we show that the Drosophila Ana2 CCCD forms a tetramer...

Organic Practices for the Production of Muskmelon

Muskmelon RFR-A1107 Jean Batzer, assistant scientist Steven Johnson, undergraduate student Mark Gleason, professor/extension plant pathologist Department of Plant Pathology Introduction Cucurbit crops

Evaluation of Fungicide Efficacy on Creeping Bentgrass

Efficacy on Creeping Bentgrass RFR-A1106 Mark Gleason, professor/extension plant pathologist Steven Johnson, undergraduate student Jean Batzer, assistant scientist Department of Plant Pathology

Identification of False-Positive QuantiFERON-TB Gold In-Tube Assays by Repeat Testing in HIV-Infected Patients at Low Risk for Tuberculosis

The QuantiFERON-TB Gold In-Tube assay (QFT) is increasingly being used for latent tuberculosis screening in patients infected with human immunodeficiency virus (HIV) in the United States. This is a retrospective analysis of repeating positive QFT assays as a strategy to identify false-positive results in HIV-infected patients at low risk for tuberculosis.

The Micronesia Challenge: Assessing the Relative Contribution of Stressors on Coral Reefs to Facilitate Science-to-Management Feedback

Fishing and pollution are chronic stressors that can prolong recovery of coral reefs and contribute to ecosystem decline. While this premise is generally accepted, management interventions are complicated because the contributions from individual stressors are difficult to distinguish. The present study examined the extent to which fishing pressure and pollution predicted...

Population-Based Passive Tick Surveillance and Detection of Expanding Foci of Blacklegged Ticks Ixodes scapularis and the Lyme Disease Agent Borrelia burgdorferi in Ontario, Canada

We identified ticks submitted by the public from 2008 through 2012 in Ontario, Canada, and tested blacklegged ticks Ixodes scapularis for Borrelia burgdorferi and Anaplasma phagocytophilum. Among the 18 species of ticks identified, I. scapularis, Dermacentor variabilis, Ixodes cookei and Amblyomma americanum represented 98.1% of the 14,369 ticks submitted. Rates of blacklegged...

Hidden Markov model speed heuristic and iterative HMM search procedure

L Steven Johnson 0 Sean R Eddy Elon Portugaly 0 Department of Immunology and Pathology, Washington University School of Medicine , St. Louis, Missouri , USA Background: Profile hidden Markov models

Timing is everything: the regulation of type III secretion

Type Three Secretion Systems (T3SSs) are essential virulence determinants of many Gram-negative bacteria. The T3SS is an injection device that can transfer bacterial virulence proteins directly into host cells. The apparatus is made up of a basal body that spans both bacterial membranes and an extracellular needle that possesses a channel that is thought to act as a conduit for...

Semaphorin-7A Is an Erythrocyte Receptor for P. falciparum Merozoite-Specific TRAP Homolog, MTRAP

The motility and invasion of Plasmodium parasites is believed to require a cytoplasmic actin-myosin motor associated with a cell surface ligand belonging to the TRAP (thrombospondin-related anonymous protein) family. Current models of invasion usually invoke the existence of specific receptors for the TRAP-family ligands on the surface of the host cell; however, the identities of...

Crystal structures of the CPAP/STIL complex reveal its role in centriole assembly and human microcephaly

Centrioles organise centrosomes and template cilia and flagella. Several centriole and centrosome proteins have been linked to microcephaly (MCPH), a neuro-developmental disease associated with small brain size. CPAP (MCPH6) and STIL (MCPH7) are required for centriole assembly, but it is unclear how mutations in them lead to microcephaly. We show that the TCP domain of CPAP...

Distinct Binding and Immunogenic Properties of the Gonococcal Homologue of Meningococcal Factor H Binding Protein

Neisseria meningitidis is a leading cause of sepsis and meningitis. The bacterium recruits factor H (fH), a negative regulator of the complement system, to its surface via fH binding protein (fHbp), providing a mechanism to avoid complement-mediated killing. fHbp is an important antigen that elicits protective immunity against the meningococcus and has been divided into three...

Electrical protein detection in cell lysates using high-density peptide-aptamer microarrays

Background The dissection of biological pathways and of the molecular basis of disease requires devices to analyze simultaneously a staggering number of protein isoforms in a given cell under given conditions. Such devices face significant challenges, including the identification of probe molecules specific for each protein isoform, protein immobilization techniques with...