40Ar/39Ar Ages of Carbonaceous Xenoliths in 2 HED Meteorites

The generally young K/Ar and 40Ar/39Ar ages of CM chondrites made us wonder whether carbonaceous xenoliths (CMX) entombed in HowarditeEucriteDiogenite (HED) meteorites might retain more radiogenic 40Ar than do free-range CM-chondrites. To find out, we selected two HED breccias with carbonaceous inclusions in order to compare the 40Ar/39Ar release patterns and ages of the inclusions with those of nearby HED material. Carbonaceous inclusions (CMXs) in two HED meteorites lost a greater fraction of radiogenic 40Ar than did surrounding host material, but a smaller fraction of it than did free-range CM-chondrites such as Murchison or more heavily altered ones. Importantly, however, the siting of the CMXs in HED matrix did not prevent the 40Ar loss of about 40 percent of the radiogenic 40Ar, even from phases that degas at high laboratory temperatures. We infer that carbonaceous asteroids with perihelia of 1 astronomical unit probably experience losses of at least this size. The usefulness of 40Ar/39Ar dating for samples returned from C-type asteroids may hinge, therefore, on identifying and analyzing separately small quantities of the most retentive phases of carbonaceous chondrites

Appropriate Use of CT Perfusion following Aneurysmal Subarachnoid Hemorrhage: A Bayesian Analysis Approach

These investigators evaluated the test characteristics of CTP in patients with SAH for detection of delayed cerebral ischemia. Ninety-seven patients were assessed with CTP for ischemia and with DSA for vasospasm. The authors concluded that positive CTP findings identified patients who should be carefully considered for induced hypertension, hypervolemia, and hemodilution and/or intra-arterial therapy while negative CTP findings are useful in guiding a no-treatment decision. BACKGROUND AND PURPOSE: In recent years CTP has been used as a complementary diagnostic tool in the evaluation of delayed cerebral ischemia and vasospasm. Our aim was to determine the test characteristics of CTP for detecting delayed cerebral ischemia and vasospasm in SAH, and then to apply Bayesian analysis to identify subgroups for its appropriate use. MATERIALS AND METHODS: Our retrospective cohort comprised consecutive patients with SAH and CTP performed between days 6 and 8 following aneurysm rupture. Delayed cerebral ischemia was determined according to primary outcome measures of infarction and/or permanent neurologic deficits. Vasospasm was determined by using DSA. The test characteristics of CTP and its 95% CIs were calculated. Graphs of conditional probabilities were constructed by using Bayesian techniques. Local treatment thresholds (posttest probability of delayed cerebral ischemia needed to initiate induced hypertension, hypervolemia, and hemodilution or intra-arterial therapy) were determined via a survey of 6 independent neurologists. RESULTS: Ninety-seven patients with SAH were included in the study; 39% (38/97) developed delayed cerebral ischemia. Qualitative CTP deficits were seen in 49% (48/97), occurring in 84% (32/38) with delayed cerebral ischemia and 27% (16/59) without. The sensitivity, specificity, and positive and negative predictive values (95% CI) for CTP were 0.84 (0.73-0.96), 0.73 (0.62-0.84), 0.67 (0.51-0.79), and 0.88 (0.74-0.94), respectively. A subgroup of 57 patients underwent DSA; 63% (36/57) developed vasospasm. Qualitative CTP deficits were seen in 70% (40/57), occurring in 97% (35/36) with vasospasm and 23% (5/21) without. The sensitivity, specificity, and positive and negative predictive values (95% CI) for CTP were 0.97 (0.92-1.0), 0.76 (0.58-0.94), 0.88 (0.72-0.95), and 0.94 (0.69-0.99), respectively. Treatment thresholds were determined as 30% for induced hypertension, hypervolemia, and hemodilution and 70% for intra-arterial therapy. CONCLUSIONS: Positive CTP findings identify patients who should be carefully considered for induced hypertension, hypervolemia, and hemodilution and/or intra-arterial therapy while negative CTP findings are useful in guiding a no-treatment decision

Seeing two faces together: preference formation in humans and rhesus macaques

Humans, great apes and old world monkeys show selective attention to faces depending on conspecificity, familiarity, and social status supporting the view that primates share similar face processing mechanisms. Although many studies have been done on face scanning strategy in monkeys and humans, the mechanisms influencing viewing preference have received little attention. To determine how face categories influence viewing preference in humans and rhesus macaques (Macaca mulatta), we performed two eye-tracking experiments using a visual preference task whereby pairs of faces from different species were presented simultaneously. The results indicated that viewing time was significantly influenced by the pairing of the face categories. Humans showed a strong bias towards an own-race face in an Asian–Caucasian condition. Rhesus macaques directed more attention towards non-human primate faces when they were paired with human faces, regardless of the species. When rhesus faces were paired with faces from Barbary macaques (Macaca sylvanus) or chimpanzees (Pan troglodytes), the novel species’ faces attracted more attention. These results indicate that monkeys’ viewing preferences, as assessed by a visual preference task, are modulated by several factors, species and dominance being the most influential

The Grizzly, February 10, 2011

Bonners Give Insight on Organization • Kappa Alpha Psi Fraternity to Participate in Spring Intake • Future UC President Dr. Bobby Fong Receives National Award • Ursinus College Plays Host to W. R. Crigler • GRE Makeover and Helpful Hints to Ace the Test • Calvin Levels Performs One Man Show in the Blackbox • New Program Brings Students and Professors Closer • Internship Profile: Matt Angle • Opinion: UC Town Hall Meeting Proved a Bit Disappointing; Letter to a Writer; A Multicultural Ursinus Campus on the Way; Upheaval in the Middle East: Why Students Should Care • Murren Adds Name to History Books During Seasonhttps://digitalcommons.ursinus.edu/grizzlynews/1829/thumbnail.jp

The Grizzly, October 28, 2010

Junot Diaz Speaks to Ursinus Campus • Berman Celebrates 20th Anniversary with Open House • Active Minds Talks About Mental Illness • Ursinus Music Department Active on Campus • UC Homecoming 2010 • Senior Explores Middle East • Students Celebrate Writing • Internship Spotlight: Jason Ward • Finally, Ursinus Creates an Arena for Race Relations • Once Upon a Potty • Letter to the Editor • Hey UC, Give Me a [Fall] Break • Bears Travel in Packs During Cross Country Season • Women\u27s Rugby Takes on Scranton This Saturdayhttps://digitalcommons.ursinus.edu/grizzlynews/1822/thumbnail.jp

Bibliometrics of systematic reviews : analysis of citation rates and journal impact factors

Background: Systematic reviews are important for informing clinical practice and health policy. The aim of this study was to examine the bibliometrics of systematic reviews and to determine the amount of variance in citations predicted by the journal impact factor (JIF) alone and combined with several other characteristics. Methods: We conducted a bibliometric analysis of 1,261 systematic reviews published in 2008 and the citations to them in the Scopus database from 2008 to June 2012. Potential predictors of the citation impact of the reviews were examined using descriptive, univariate and multiple regression analysis. Results: The mean number of citations per review over four years was 26.5 (SD +/-29.9) or 6.6 citations per review per year. The mean JIF of the journals in which the reviews were published was 4.3 (SD +/-4.2). We found that 17% of the reviews accounted for 50% of the total citations and 1.6% of the reviews were not cited. The number of authors was correlated with the number of citations (r = 0.215, P =5.16) received citations in the bottom quartile (eight or fewer), whereas 9% of reviews published in the lowest JIF quartile (<=2.06) received citations in the top quartile (34 or more). Six percent of reviews in journals with no JIF were also in the first quartile of citations. Conclusions: The JIF predicted over half of the variation in citations to the systematic reviews. However, the distribution of citations was markedly skewed. Some reviews in journals with low JIFs were well-cited and others in higher JIF journals received relatively few citations; hence the JIF did not accurately represent the number of citations to individual systematic reviews

Accuracy of Using Visual Identification of White Sharks to Estimate Residency Patterns

Determining the residency of an aquatic species is important but challenging and it remains unclear what is the best sampling methodology. Photo-identification has been used extensively to estimate patterns of animals' residency and is arguably the most common approach, but it may not be the most effective approach in marine environments. To examine this, in 2005, we deployed acoustic transmitters on 22 white sharks (Carcharodon carcharias) in Mossel Bay, South Africa to quantify the probability of detecting these tagged sharks by photo-identification and different deployment strategies of acoustic telemetry equipment. Using the data collected by the different sampling approaches (detections from an acoustic listening station deployed under a chumming vessel versus those from visual sightings and photo-identification), we quantified the methodologies' probability of detection and determined if the sampling approaches, also including an acoustic telemetry array, produce comparable results for patterns of residency. Photo-identification had the lowest probability of detection and underestimated residency. The underestimation is driven by various factors primarily that acoustic telemetry monitors a large area and this reduces the occurrence of false negatives. Therefore, we propose that researchers need to use acoustic telemetry and also continue to develop new sampling approaches as photo-identification techniques are inadequate to determine residency. Using the methods presented in this paper will allow researchers to further refine sampling approaches that enable them to collect more accurate data that will result in better research and more informed management efforts and policy decisions

The Grizzly, September 30, 2010

President Emeritus John R. Strassburger: In Memoriam • Moving Memorial Service in Bomberger Hall Honors Late President • Students Test Out New Foods with SASA • Student Achievement in the Arts • The Makings of a More Colorful Ursinus Campus • UC Fringe Festival • Family Day Brings Community Together • Video Games Heighten Reflexes • UC SERV Changes Name to UC EMS • UC Alumni: Reflections on a Legacy • Seeking Tenure: Dr. Louise Woodstock • Strassburger Supports Biology • Strassburger Leaves UC with Pride • Remembering President Emeritus John Strassburger • President Strassburger Revitalizes Courts to Scoreboards • Ursinus Coaching Staff Remembers Their Number One Fan • UC Football Wins Big • Senior Spotlight: Alex Shivers, Women\u27s Soccerhttps://digitalcommons.ursinus.edu/grizzlynews/1819/thumbnail.jp

Comparison of sequencing-based methods to profile DNA methylation and identification of monoallelic epigenetic modifications.

Analysis of DNA methylation patterns relies increasingly on sequencing-based profiling methods. The four most frequently used sequencing-based technologies are the bisulfite-based methods MethylC-seq and reduced representation bisulfite sequencing (RRBS), and the enrichment-based techniques methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylated DNA binding domain sequencing (MBD-seq). We applied all four methods to biological replicates of human embryonic stem cells to assess their genome-wide CpG coverage, resolution, cost, concordance and the influence of CpG density and genomic context. The methylation levels assessed by the two bisulfite methods were concordant (their difference did not exceed a given threshold) for 82% for CpGs and 99% of the non-CpG cytosines. Using binary methylation calls, the two enrichment methods were 99% concordant and regions assessed by all four methods were 97% concordant. We combined MeDIP-seq with methylation-sensitive restriction enzyme (MRE-seq) sequencing for comprehensive methylome coverage at lower cost. This, along with RNA-seq and ChIP-seq of the ES cells enabled us to detect regions with allele-specific epigenetic states, identifying most known imprinted regions and new loci with monoallelic epigenetic marks and monoallelic expression

Comparison of the clinical and economic outcomes between open and minimally invasive appendectomy and colectomy: evidence from a large commercial payer database

Background: Appendectomy and colectomy are commonly performed surgical procedures. Despite evidence demonstrating advantages with the minimally invasive surgical (MIS) approach, open procedures occur with greater prevalence. Therefore, there is still controversy as to whether the MIS approach is safer or more cost effective. Methods: A retrospective analysis was performed using a large commercial payer database. The data included information on 7,532 appendectomies and 2,745 colectomies. Data on the distribution of patient demographic and comorbidity characteristics associated with the MIS and open approaches were reviewed. The corresponding complication rates and expenditures were analyzed. Summary statistics were compared using chi-square tests, and generalized linear models were constructed to estimate expenditures while controlling for patient characteristics. Results: The patients undergoing MIS and open colectomy showed no significant variations in age distribution or marginal age differences for appendectomy. Significantly more patients experienced an infection postoperatively, and procedure-specific complications were more common in the open group for both procedures (P < 0.05). The postsurgical hospital stay was longer for the patients treated using the open techniques, differing an average of half a day for appendectomies and significantly more (4 days) for colectomy (P < 0.05). Readmission rates differed little between the two approaches. Procedures performed through an MIS approach were associated with lower expenditures than for the open technique, with differences ranging from $700 for appendectomy patients (P < 0.05) to$15,200 for colectomy patients (P < 0.05). Conclusions: Minimally invasive appendectomy and colectomy were associated with lower infection rates, fewer complications, shorter hospital stays, and lower expenditures than open surgery