179 research outputs found
Dissemination and Systemic Colonization of Uropathogenic Escherichia coli in a Murine Model of Bacteremia
Infection with uropathogenic Escherichia coli (UPEC), the causative agent of most uncomplicated urinary tract infections, proceeds in an ascending manner and, if left untreated, may result in bacteremia and urosepsis. To examine the fate of UPEC after its entry into the bloodstream, we developed a murine model of sublethal bacteremia. CBA/J mice were inoculated intravenously with 1 × 106 CFU of pyelonephritis strain E. coli CFT073 carrying a bioluminescent reporter. Biophotonic imaging, used to monitor the infection over 48 h, demonstrated that the bacteria disseminated systemically and appeared to localize at discrete sites. UPEC was recovered from the spleen, liver, kidneys, lungs, heart, brain, and intestines as early as 20 min postinoculation, peaking at 24 h postinoculation. A nonpathogenic E. coli K-12 strain, however, disseminated at significantly lower levels (P < 0.01) and was cleared from the liver and cecum by 24 h postinoculation. Isogenic mutants lacking type 1 fimbriae, P fimbriae, capsule, TonB, the heme receptors Hma and ChuA, or particularly the sialic acid catabolism enzyme NanA were significantly outcompeted by wild-type CFT073 during bacteremia (P < 0.05), while flagellin and hemolysin mutants were not
Do Open Access Electronic Theses and Dissertations Diminish Publishing Opportunities in the Sciences?
In academia, there is a growing acceptance of sharing the final electronic version of graduate work, such as a thesis or dissertation, in an online university repository. Though previous studies have shown that journal editors are willing to consider manuscripts derived from electronic theses and dissertations (ETDs), faculty advisors and graduate students continue to raise concerns that online discoverability of ETDs negatively impact future opportunities to publish those findings. The current study investigated science journal policies on open access ETDs and found that more than half of the science journals responding (51.4%) reported that manuscripts derived from openly accessible ETDs are welcome for submission and an additional 29.1 percent would accept revised ETDs under certain conditions
Analysis of Hendra Virus Fusion Protein N-Terminal Transmembrane Residues
Hendra virus (HeV) is a zoonotic enveloped member of the family Paramyoxviridae. To successfully infect a host cell, HeV utilizes two surface glycoproteins: the attachment (G) protein to bind, and the trimeric fusion (F) protein to merge the viral envelope with the membrane of the host cell. The transmembrane (TM) region of HeV F has been shown to have roles in F protein stability and the overall trimeric association of F. Previously, alanine scanning mutagenesis has been performed on the C-terminal end of the protein, revealing the importance of β-branched residues in this region. Additionally, residues S490 and Y498 have been demonstrated to be important for F protein endocytosis, needed for the proteolytic processing of F required for fusion. To complete the analysis of the HeV F TM, we performed alanine scanning mutagenesis to explore the residues in the N-terminus of this region (residues 487–506). In addition to confirming the critical roles for S490 and Y498, we demonstrate that mutations at residues M491 and L492 alter F protein function, suggesting a role for these residues in the fusion process
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Major and Minor Group Rhinoviruses Elicit Differential Signaling and Cytokine Responses as a Function of Receptor-Mediated Signal Transduction
Major- and minor-group human rhinoviruses (HRV) enter their host by binding to the cell surface molecules ICAM-1 and LDL-R, respectively, which are present on both macrophages and epithelial cells. Although epithelial cells are the primary site of productive HRV infection, previous studies have implicated macrophages in establishing the cytokine dysregulation that occurs during rhinovirus-induced asthma exacerbations. Analysis of the transcriptome of primary human macrophages exposed to major- and minor-group HRV demonstrated differential gene expression. Alterations in gene expression were traced to differential mitochondrial activity and signaling pathway activation between two rhinovirus serotypes, HRV16 (major-group) and HRV1A (minor-group), upon initial HRV binding. Variances in phosphorylation of kinases (p38, JNK, ERK5) and transcription factors (ATF-2, CREB, CEBP-alpha) were observed between the major- and minor-group HRV treatments. Differential activation of signaling pathways led to changes in the production of the asthma-relevant cytokines CCL20, CCL2, and IL-10. This is the first report of genetically similar viruses eliciting dissimilar cytokine release, transcription factor phosphorylation, and MAPK activation from macrophages, suggesting that receptor use is a mechanism for establishing the inflammatory microenvironment in the human airway upon exposure to rhinovirus
Making Room for Zoom in Focus Group Methods: Opportunities and Challenges for Novice Researchers (During and Beyond COVID-19)
Als die COVID-19-Pandemie über die Welt hereinbrach, waren viele Menschen gezwungen, sich auf online-basierte Routinen einzustellen, darunter auch qualitative Forscher*innen, die nach alternativen Möglichkeiten zur Erhebung aussagekräftiger Daten suchten. Während Fokusgruppen traditionell Face to Face durchgeführt werden, bieten Fortschritte bei Online-Videokonferenzanwendungen neue Methoden zur Datenerhebung, die jedoch bisher nur selten untersucht wurden. In diesem Artikel berichten wir über die Erfahrungen von 12 Doktorand*innen mit der Durchführung von Fokusgruppen unter Verwendung von Zoom im Rahmen eines Kurses zu qualitativen Interviewmethoden. Wir reflektieren Chancen und Herausforderungen, die wir als Moderator*innen und Teilnehmer*innen bei der Nutzung von Zoom erlebten z.B. bei der Vorbereitung oder in Bezug auf Rapport, die Einbindung anderer digitaler Tools und von Internetverbindungen. Zusammenfassend lässt sich sagen, dass die Durchführung von Online-Fokusgruppen unter Verwendung von Zoom insgesamt eine positive Erfahrung war und mit Face-to-Face-Fokusgruppen vergleichbar ist. Möglichkeiten der Teilnehmer*innenrekrutierung, die Sicherheitsmerkmale von Zoom und die Nutzung von Zoom und allgemeiner neuen Technologien sollten auch jenseits der Pandemie weiter erforscht werden.As the COVID-19 pandemic swept through the world, it forced many people to adapt to an online-based routine, including qualitative researchers looking for alternative ways to collect meaningful data. While focus groups are traditionally conducted in-person, advances with online videoconferencing applications present a new method to collect data, however, few studies have explored this. In this article we present 12 doctoral students' experiences with conducting focus groups using the videoconferencing application Zoom during a qualitative methods course on interviewing methods. Through this self-study qualitative analysis, participants reflected on the opportunities and challenges experienced as both moderators and participants using Zoom including: preparation, rapport, incorporating other digital tools, and internet connectivity. In conclusion, doing focus groups online using Zoom was a positive experience overall and comparable to in-person focus groups for collecting qualitative data, despite the introduction of technology. More research on participant recruitment, new technology, Zoom's security features, and Zoom's use outside of a pandemic should be further explored
Content Validity of the Geriatric Depression Scale in Inpatient Health Care Settings
The content validity of the Geriatric Depression Scale (GDS) for use in inpatient health care settings was evaluated. Clinical experience has shown that one or more questions may not be appropriate in such settings. These questions ask about behaviors or feelings with which the examinee may not be able to identify with because they have been in an inpatient setting during the past week. Twenty-five Subject Matter Experts (SMEs) evaluated the GDS-30 as to whether each item appropriately assesses the construct of depression for inpatients in a medical care setting. SMEs were identified by an online search of the Florida Division of Medical Quality Assurance database; inclusion criteria are presented. Nineteen SMEs held a Ph.D. and six held a Psy.D. Years of post-licensure practice experience ranged from 10 to 48 years with a mean of 23.12 years (SD = 10.07). Using the Content Validity Ratio, four questions emerged as inappropriate (statistically significant at, or below, an alpha level of .025). The lack of content validity of these questions necessitates their omission when psychometrically assessing depression in elderly inpatients. Recommended revised cutoff values are presented. Utilizing the recommended modification to the GDS presented here should reduce false positives when psychometrically assessing depression in elderly inpatients
A Description of Quasar Variability Measured Using Repeated SDSS and POSS Imaging
We provide a quantitative description and statistical interpretation of the
optical continuum variability of quasars. The Sloan Digital Sky Survey (SDSS)
has obtained repeated imaging in five UV-to-IR photometric bands for 33,881
spectroscopically confirmed quasars. About 10,000 quasars have an average of 60
observations in each band obtained over a decade along Stripe 82 (S82), whereas
the remaining ~25,000 have 2-3 observations due to scan overlaps. The observed
time lags span the range from a day to almost 10 years, and constrain quasar
variability at rest-frame time lags of up to 4 years, and at rest-frame
wavelengths from 1000A to 6000A. We publicly release a user-friendly catalog of
quasars from the SDSS Data Release 7 that have been observed at least twice in
SDSS or once in both SDSS and the Palomar Observatory Sky Survey, and we use it
to analyze the ensemble properties of quasar variability. Based on a damped
random walk (DRW) model defined by a characteristic time scale and an
asymptotic variability amplitude that scale with the luminosity, black hole
mass, and rest wavelength for individual quasars calibrated in S82, we can
fully explain the ensemble variability statistics of the non-S82 quasars such
as the exponential distribution of large magnitude changes. All available data
are consistent with the DRW model as a viable description of the optical
continuum variability of quasars on time scales of ~5-2000 days in the rest
frame. We use these models to predict the incidence of quasar contamination in
transient surveys such as those from PTF and LSST.Comment: 33 pages, 19 figures, replaced with accepted version. Catalog is
available at http://www.astro.washington.edu/users/ivezic/macleod/qso_dr7
Argumentation in school science : Breaking the tradition of authoritative exposition through a pedagogy that promotes discussion and reasoning
The value of argumentation in science education has become internationally recognised and has been the subject of many research studies in recent years. Successful introduction of argumentation activities in learning contexts involves extending teaching goals beyond the understanding of facts and concepts, to include an emphasis on cognitive and metacognitive processes, epistemic criteria and reasoning. The authors focus on the difficulties inherent in shifting a tradition of teaching from one dominated by authoritative exposition to one that is more dialogic, involving small-group discussion based on tasks that stimulate argumentation. The paper builds on previous research on enhancing the quality of argument in school science, to focus on how argumentation activities have been designed, with appropriate strategies, resources and modelling, for pedagogical purposes. The paper analyses design frameworks, their contexts and lesson plans, to evaluate their potential for enhancing reasoning through foregrounding the processes of argumentation. Examples of classroom dialogue where teachers adopt the frameworks/plans are analysed to show how argumentation processes are scaffolded. The analysis shows that several layers of interpretation are needed and these layers need to be aligned for successful implementation. The analysis serves to highlight the potential and limitations of the design frameworks
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Genomic Profiling of Childhood Tumor Patient-Derived Xenograft Models to Enable Rational Clinical Trial Design.
Accelerating cures for children with cancer remains an immediate challenge as a result of extensive oncogenic heterogeneity between and within histologies, distinct molecular mechanisms evolving between diagnosis and relapsed disease, and limited therapeutic options. To systematically prioritize and rationally test novel agents in preclinical murine models, researchers within the Pediatric Preclinical Testing Consortium are continuously developing patient-derived xenografts (PDXs)-many of which are refractory to current standard-of-care treatments-from high-risk childhood cancers. Here, we genomically characterize 261 PDX models from 37 unique pediatric cancers; demonstrate faithful recapitulation of histologies and subtypes; and refine our understanding of relapsed disease. In addition, we use expression signatures to classify tumors for TP53 and NF1 pathway inactivation. We anticipate that these data will serve as a resource for pediatric oncology drug development and will guide rational clinical trial design for children with cancer
Volume 05
Introduction from Dean Dr. Charles Ross
The Tallis House as an Extension of Emily Tallis in McEwan\u27s Atonement by Ian Karamarkovich
Graphic Design by Jessica Cox
Graphic Design by Kyle Fowlkes
Graphic Design by Allison Pawlowski
Incorporating Original Research in The Classroom: A Case Study Analyzing the Influence of the Chesapeake Bay on Local Temperatures by Kaitlin Major, Carrie Dunham and Dr. Kelsey Scheitlin
Graphic Design by Kathryn Grayson
Graphic Design by Ashley Johnson
Facing the Music: Environmental Impact Assessment of Building A Concert Hall on North Campus by Jennifer Nehrt, Kelsey Stolzenbach And Dr. Kelsey Scheitlin
Art by Kristin McQuarrie
Art by Sara Nelson
Art by Melisa Michelle
Prosocial Behavior as a Result of Prosocial Music by Jessica Sudlow
Graphic Design by Perry Bason
Graphic Design by Danielle Dmuchawski
Graphic Design by Mariah Asbell
Graphic Design by Matthew Sakach
Identifying Pathogenic Salmonella Serotypes Isolated from Prince Edward County, VA Waterways via Mutiplex PCR Analysis by Timothy Smith, Jr.
Art by Annaliese Troxell
Art by T. Dane Summerell
Development of Salicylidene Anilines for Application in the High School Laboratory by Sarah Ganrude
Graphic Design by Malina Rutherford
Graphic Design by Hannah Hopper, and Matthew Sakach
Because That\u27s What Daddies Do: Effects of Fathering Patterns on Son\u27s Self and Gender Identities by John Berry, Jr.
Graphic Design by James Early
Graphic Design by Colleen Festa
The Influence of Tropical Cyclones on Chesapeake Bay Dead Zones by Chelsea D. Taylor and Dr. Kelsey Scheitlin
Graphic Design by Michelle Maddox
Graphic Design by Kaitlyn Smith
Graphic Design by Sarah Schu
Graphic Design by Perry Bason, Cabell Edmunds, Katherine Grayson, Matthew Sakach, and Kayla Torna
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