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Calling Up the Dead
Calling Up the Dead is a collection of seven short stories which all take place over the final hours of December 31, 1999 and the first few hours of January 1, 2000. The themes of time, history, and the reactions toward the new millennium (positive, negative, indifferent) of a variety of cultures are addressed. Each of the six major continents has a story, along with its cultural perspective, delivered by narrators both young and old, three female, three male and one balcony
A CSO Search for -CH: Detection in the Orion Bar PDR
The results of a Caltech Submillimeter Observatory (CSO) search for
-CH, first detected by Pety et al. (2012) in observations toward the
Horsehead photodissociation region (PDR), are presented. A total of 39 sources
were observed in the 1 mm window. Evidence of emission from -CH is
found in only a single source - the Orion Bar PDR region, which shows a
rotational temperature of 178(13) K and a column density of 7(2) x
cm. In the remaining sources, upper limits of ~10
cm are found. These results are discussed in the context of guiding
future observational searches for this species.Comment: 9 pages, 8 figures, 4 table
Antibiotic-resistant Escherichia Coli from Retail Poultry Meat with Different Antibiotic Use Claims
Background We sought to determine if the prevalence of antibiotic-resistant Escherichia coli differed across retail poultry products and among major production categories, including organic, âraised without antibioticsâ, and conventional. Results We collected all available brands of retail chicken and turkeyâincluding conventional, âraised without antibioticâ, and organic productsâevery two weeks from January to December 2012. In total, E. coli was recovered from 91% of 546 turkey products tested and 88% of 1367 chicken products tested. The proportion of samples contaminated with E. coli was similar across all three production categories. Resistance prevalence varied by meat type and was highest among E. coli isolates from turkey for the majority of antibiotics tested. In general, production category had little effect on resistance prevalence among E. coli isolates from chicken, although resistance to gentamicin and multidrug resistance did vary. In contrast, resistance prevalence was significantly higher for 6 of the antibiotics testedâand multidrug resistanceâamong isolates from conventional turkey products when compared to those labelled organic or âraised without antibioticsâ. E. coli isolates from chicken varied strongly in resistance prevalence among different brands within each production category. Conclusion The high prevalence of resistance among E. coli isolates from conventionally-raised turkey meat suggests greater antimicrobial use in conventional turkey production as compared to âraised without antibioticsâ and organic systems. However, among E. coli from chicken meat, resistance prevalence was more strongly linked to brand than to production category, which could be caused by brand-level differences during production and/or processing, including variations in antimicrobial use
Intermingled Klebsiella pneumoniae Populations Between Retail Meats and Human Urinary Tract Infections
Background.âKlebsiella pneumoniae is a common colonizer of the gastrointestinal tract of humans, companion animals, and livestock. To better understand potential contributions of foodborne K. pneumoniae to human clinical infections, we compared K. pneumoniae isolates from retail meat products and human clinical specimens to assess their similarity based on antibiotic resistance, genetic relatedness, and virulence. Methods.âKlebsiella pneumoniae was isolated from retail meats from Flagstaff grocery stores in 2012 and from urine and blood specimens from Flagstaff Medical Center in 2011â2012. Isolates underwent antibiotic susceptibility testing and whole-genome sequencing. Genetic relatedness of the isolates was assessed using multilocus sequence typing and phylogenetic analyses. Extraintestinal virulence of several closely related meat-source and urine isolates was assessed using a murine sepsis model. Results.âMeat-source isolates were significantly more likely to be multidrug resistant and resistant to tetracycline and gentamicin than clinical isolates. Four sequence types occurred among both meat-source and clinical isolates. Phylogenetic analyses confirmed close relationships among meat-source and clinical isolates. Isolates from both sources showed similar virulence in the mouse sepsis model. Conclusions.âMeat-source K. pneumoniae isolates were more likely than clinical isolates to be antibiotic resistant, which could reflect selective pressures from antibiotic use in food-animal production. The close genetic relatedness of meat-source and clinical isolates, coupled with similarities in virulence, suggest that the barriers to transmission between these 2 sources are low. Taken together, our results suggest that retail meat is a potential vehicle for transmitting virulent, antibiotic-resistant K. pneumoniae from food animals to humans
The Grizzly, November 1, 2012
Search for Student Activities ⢠Presidential Debate Wrap-Up ⢠Staff Editorial ⢠Homecoming 2012 ⢠24-Hour Play Set to Begin Friday ⢠Departments Revise Curriculums ⢠Students Prepare for November 6 Election ⢠Campus Radio Grows ⢠Up \u27Til Dawn Fights Kids\u27 Cancer ⢠Opinion: Presidential Candidates Head to Head; No Matter Political Affiliation, College Students Need to Vote; Reaction to Sports Opinion Piece ⢠Football Falls to JHUhttps://digitalcommons.ursinus.edu/grizzlynews/1868/thumbnail.jp
Recombination in West Nile Virus: minimal contribution to genomic diversity
Recombination is known to play a role in the ability of various viruses to acquire sequence diversity. We consequently examined all available West Nile virus (WNV) whole genome sequences both phylogenetically and with a variety of computational recombination detection algorithms. We found that the number of distinct lineages present on a phylogenetic tree reconstruction to be identical to the 6 previously reported. Statistically-significant evidence for recombination was only observed in one whole genome sequence. This recombination event was within the NS5 polymerase coding region. All three viruses contributing to the recombination event were originally isolated in Africa at various times, with the major parent (SPU116_89_B), minor parent (KN3829), and recombinant sequence (AnMg798) belonging to WNV taxonomic lineages 2, 1a, and 2 respectively. This one isolated recombinant genome was out of a total of 154 sequences analyzed. It therefore does not seem likely that recombination contributes in any significant manner to the overall sequence variation within the WNV genome
Machine learning optimised hyperspectral remote sensing retrieves cotton nitrogen status
Hyperspectral imaging spectrometers mounted on unmanned aerial vehicle (UAV) can capture high spatial and spectral resolution to provide cotton crop nitrogen status for precision agriculture. The aim of this research was to explore machine learning use with hyperspectral datacubes over agricultural fields. Hyperspectral imagery was collected over a mature cotton crop, which had high spatial (~5.2 cm) and spectral (5 nm) resolution over the spectral range 475â925 nm that allowed discrimination of individual crop rows and field features as well as a continuous spectral range for calculating derivative spectra. The nominal reflectance and its derivatives clearly highlighted the different treatment blocks and were strongly related to N concentration in leaf and petiole samples, both in traditional vegetation indices (e.g., Vogelman 1, R2 = 0.8) and novel combinations of spectra (R2 = 0.85). The key hyperspectral bands identified were at the red-edge inflection point (695â715 nm). Satellite multispectral was compared against the UAV hyperspectral remote sensingâs performance by testing the ability of Sentinel MSI to predict N concentration using the bands in VIS-NIR spectral region. The Sentinel 2A Green band (B3; mid-point 559.8 nm) explained the same amount of variation in N as the hyperspectral data and more than the Sentinel Red Edge Point 1 (B5; mid-point 704.9 nm) with the lower 10 m resolution Green band reporting an R2 = 0.85, compared with the R2 = 0.78 of downscaled Sentinel Red Edge Point 1 at 5 m. The remaining Sentinel bands explained much lower variation (maximum was NIR at R2 = 0.48). Investigation of the red edge peak region in the first derivative showed strong promise with RIDAmid (R2 = 0.81) being the best index. The machine learning approach narrowed the range of bands required to investigate plant condition over this trial site, greatly improved processing time and reduced processing complexity. While Sentinel performed well in this comparison and would be useful in a broadacre crop production context, the impact of pixel boundaries relative to a region of interest and coarse spatial and temporal resolution impacts its utility in a research capacity
Venezuelan Equine Encephalitis Virus in Iquitos, Peru: Urban Transmission of a Sylvatic Strain
Enzootic strains of Venezuelan equine encephalitis virus (VEEV) have been isolated from febrile patients in the Peruvian Amazon Basin at low but consistent levels since the early 1990s. Through a clinic-based febrile surveillance program, we detected an outbreak of VEEV infections in Iquitos, Peru, in the first half of 2006. The majority of these patients resided within urban areas of Iquitos, with no report of recent travel outside the city. To characterize the risk factors for VEEV infection within the city, an antibody prevalence study was carried out in a geographically stratified sample of urban areas of Iquitos. Additionally, entomological surveys were conducted to determine if previously incriminated vectors of enzootic VEEV were present within the city. We found that greater than 23% of Iquitos residents carried neutralizing antibodies against VEEV, with significant associations between increased antibody prevalence and age, occupation, mosquito net use, and overnight travel. Furthermore, potential vector mosquitoes were widely distributed across the city. Our results suggest that while VEEV infection is more common in rural areas, transmission also occurs within urban areas of Iquitos, and that further studies are warranted to identify the precise vectors and reservoirs involved in urban VEEV transmission
DESI Survey Validation Spectra Reveal an Increasing Fraction of Recently Quenched Galaxies at
We utilize bright Luminous Red Galaxies (LRGs) from the novel
Dark Energy Spectroscopic Instrument Survey Validation spectroscopic sample,
leveraging its deep ( hour/galaxy exposure time) spectra to
characterize the contribution of recently quenched galaxies to the massive
galaxy population at . We use Prospector to infer non-parametric
star formation histories and identify a significant population of
post-starburst galaxies that have joined the quiescent population within the
past Gyr. The highest redshift subset (277 at ) of our sample of
recently quenched galaxies represents the largest spectroscopic sample of
post-starburst galaxies at that epoch. At , we measure the number
density of quiescent LRGs, finding that recently quenched galaxies constitute a
growing fraction of the massive galaxy population with increasing lookback
time. Finally, we quantify the importance of this population amongst massive
() LRGs by measuring the fraction of
stellar mass each galaxy formed in the Gyr before observation, . Although galaxies with are rare at
( of the population), by they constitute
of massive galaxies. Relaxing this threshold, we find that galaxies with
constitute of the massive galaxy population
at . We also identify a small but significant sample of galaxies at
that formed with , implying that they may
be analogues to high-redshift quiescent galaxies that formed on similar
timescales. Future analysis of this unprecedented sample promises to illuminate
the physical mechanisms that drive the quenching of massive galaxies after
cosmic noon.Comment: Submitted to ApJ Letters after DESI Collaboration Review. 14 pages, 5
figures, comments welcome
An unusual cause for CoffinâLowry syndrome: Three brothers with a novel microduplication in RPS6KA3
CoffinâLowry syndrome (CLS) is a rare Xâlinked disorder characterized by moderate to severe intellectual disability, hypotonia, craniofacial features, tapering digits, short stature, and skeletal deformities. Using whole exome sequencing and highâresolution targeted comparative genomic hybridization array analysis, we identified a novel microduplication encompassing exons five through nine of RPS6KA3 in three full brothers. Each brother presented with intellectual disability and clinical and radiographic features consistent with CLS. qRTâPCR analyses performed on mRNA from the peripheral blood of the three siblings revealed a marked reduction of RPS6KA3 levels suggesting a lossâofâfunction mechanism. PCR analysis of the patientsâ cDNA detected a band greater than expected for an exon 4â10 amplicon, suggesting this was likely a direct duplication that lies between exons 4 through 10, which was later confirmed by Sanger sequencing. This microduplication is only the third intragenic duplication of RPS6KA3, and the second and smallest reported to date thought to cause CLS. Our study further supports the clinical utility of methods such as nextâgeneration sequencing and highâresolution genomic arrays to detect small intragenic duplications. These methods, coupled with expression studies and cDNA structural analysis have the capacity to confirm the diagnosis of CLS in these rare cases
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