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Genetic variation of Renibacterium salmoninarum genes in infected salmonids
Renibacterium salmoninarum is the causative agent of bacterial kidney disease in both
wild and farmed salmonid species worldwide. The genome of this pathogen has
significant synteny to the ubiquitous, soil-dwelling Arthrobacter spp. though it is 1.9 Mb
smaller, suggesting that reductive evolution has occurred. Recently, our group finished
sequencing and annotation of the R. salmoninarum American Tissue Culture Collection
33209 strain, which has been cultured in vitro since 1974. The genome contained a
significant amount of inactivated genes caused by frameshift and extrachromosomal
elements. This led us to hypothesize that reduced evolutionary pressure due to lengthy
laboratory cultivation on the genome may account for the mutations found. To test this
hypothesis we analyzed four genes with different mutations typicalof mutations observed
throughout the genome using samples acquired from around the world. We used basic
molecular biology to elucidate the sequences and compared. We found that although the
ATCC 33209 strain had been cultured extensively in vitro, its sequence is representative
of what is found in nature. The mutations leading to inactivation of regions of the genome
suggests the pathogen R. salmoninarum has experienced reductive evolution
LabView Interface for School-Network DAQ Card
A low-cost DAQ card has been developed for school-network cosmic ray detector
projects, providing digitized data from photomultiplier tubes via a standard
serial interface. To facilitate analysis of these data and to provide students
with a starting point for custom readout systems, a model interface has been
developed using the National Instruments LabVIEW(R) system. This user-friendly
interface allows one to initialize the trigger coincidence conditions for
data-taking runs and to monitor incoming or pre-recorded data sets with
updating singles- and coincidence-rate plots and other user-selectable
histograms.Comment: 4 pages, 6 figures. Presented as Paper NS26-119 at IEEE-NSS 2003,
Portland, OR, by R. J. Wilke
Cytokinesis is blocked in mammalian cells transfected with Chlamydia trachomatis gene CT223
<p>Abstract</p> <p>Background</p> <p>The chlamydiae alter many aspects of host cell biology, including the division process, but the molecular biology of these alterations remains poorly characterized. Chlamydial inclusion membrane proteins (Incs) are likely candidates for direct interactions with host cell cytosolic proteins, as they are secreted to the inclusion membrane and exposed to the cytosol. The <it>inc </it>gene <it>CT223 </it>is one of a sequential set of orfs that encode or are predicted to encode Inc proteins. CT223p is localized to the inclusion membrane in all tested <it>C. trachomatis </it>serovars.</p> <p>Results</p> <p>A plasmid transfection approach was used to examine the function of the product of <it>CT223 </it>and other Inc proteins within uninfected mammalian cells. Fluorescence microscopy was used to demonstrate that <it>CT223</it>, and, to a lesser extent, adjacent <it>inc </it>genes, are capable of blocking host cell cytokinesis and facilitating centromere supranumeracy defects seen by others in chlamydiae-infected cells. Both phenotypes were associated with transfection of plasmids encoding the carboxy-terminal tail of CT223p, a region of the protein that is likely exposed to the cytosol in infected cells.</p> <p>Conclusion</p> <p>These studies suggest that certain Inc proteins block cytokinesis in <it>C. trachomatis</it>-infected cells. These results are consistent with the work of others showing chlamydial inhibition of host cell cytokinesis.</p
Low-Cost Data Acquisition Card for School-Network Cosmic Ray Detectors
The Cosmic Ray Observatory Project (CROP) at University of Nebraska/Lincoln
and the Washington Area Large-scale Time coincidence Array (WALTA) at
University of Washington/Seattle are among several outreach projects siting
cosmic-ray detectors at local high schools in cities around North America, to
study the origins and interactions of high-energy cosmic rays. In a
collaboration between QuarkNet, the outreach program based at Fermilab, CROP,
and WALTA, a low-cost data acquisition electronics card has been developed to
collect and synchronize the data from each detector site. The cost for each
card is under US$500 for parts, functionally replacing much more expensive
electronics crates and modules at each high school site. The card has 4 analog
discriminator inputs for photo-multiplier tube signals, a 4-channel
Time-to-Digital converter for local coincidence and time-over-threshold
measurements at 0.75 ns resolution, programmable trigger logic via a CPLD and
microcontroller, and a built-in low-cost GPS receiver/antenna module (via
external cable) to provide event trigger time stamps at better than 100 ns
accuracy. Temperature sensors and a barometer are also integrated to record
environmental data along with the counter data. The card connects to any PC or
laptop via a standard RS-232 serial port for data output and control. The
microcontroller and CPLD are field programmable and therefore make the card
functionality flexible and easy to upgrade.Comment: 4 pages, 4 figures, 1 table. Presented by R. J. Wilkes at "IEEE-NSS
2003", Paper N8-1, Portland, OR, November 2003. Submitted to Trans. IEE
Primary mucinous adenocarcinoma in a defunctionalized urinary bladder: a case report
<p>Abstract</p> <p>Introduction</p> <p>Malignancies are rare in defunctionalized bladders and are thought to arise from metaplasia secondary to chronic inflammation. Transitional cell and squamous cell carcinomas are the most common but there are three reported cases of mucinous adenocarcinoma.</p> <p>Case presentation</p> <p>We report a 57-year-old Caucasian man presenting with penile discharge for 30 years following ileal conduit surgery for neurogenic bladder, and who was found to have primary mucinous adenocarcinoma of his defunctionalized bladder.</p> <p>Conclusion</p> <p>Although urinary diversion without cystectomy is less common in current urologic practice, there are many patients with longstanding defunctionalized bladders. While there are no established surveillance protocols, defunctionalized bladder patients with urethral discharge should be evaluated.</p
Access Impediments to Health Care and Social Services Between Anglophone and Francophone African Immigrants Living in Philadelphia with Respect to HIV/AIDS
Objectives To describe the social and cultural differences between Anglophone and Francophone African immigrants which define the impediments that Francophone African immigrants face trying to access health and human services in Philadelphia, Pennsylvania. Methods Surveys and personal interviews were administered to participants in social events, community meetings, and health centers. A Chi-squared analysis was used to contrast the communities. Results Francophone Africans demonstrated less acculturation, education, English fluency, and more legal documentation problems, and thus face greater challenges accessing health care. Anglophone Africans had a higher level of acculturation, fewer language problems, and perceived fewer barriers in accessing health care than Francophone Africans. Conclusions Educating new immigrants, through a more culturally sensitive infectious disease treatment and prevention program, is integral to achieving a higher access and utilization rates of available services; especially in recent Francophone immigrants. A larger study is needed to extend the findings to other cities where immigrants with similar backgrounds or acculturation issues reside
Nonlinear Waves in Bose-Einstein Condensates: Physical Relevance and Mathematical Techniques
The aim of the present review is to introduce the reader to some of the
physical notions and of the mathematical methods that are relevant to the study
of nonlinear waves in Bose-Einstein Condensates (BECs). Upon introducing the
general framework, we discuss the prototypical models that are relevant to this
setting for different dimensions and different potentials confining the atoms.
We analyze some of the model properties and explore their typical wave
solutions (plane wave solutions, bright, dark, gap solitons, as well as
vortices). We then offer a collection of mathematical methods that can be used
to understand the existence, stability and dynamics of nonlinear waves in such
BECs, either directly or starting from different types of limits (e.g., the
linear or the nonlinear limit, or the discrete limit of the corresponding
equation). Finally, we consider some special topics involving more recent
developments, and experimental setups in which there is still considerable need
for developing mathematical as well as computational tools.Comment: 69 pages, 10 figures, to appear in Nonlinearity, 2008. V2: new
references added, fixed typo
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