Effect of Vacuum on the Performance of the Flame Ionization Detector Used for Vacuum-Outlet Gas Chromatography

Vacuum-outlet operation of short fused-silica open tubular columns for gas chromatography provides benefits to analysis speed by increasing the optimum velocity while minimizing the loss in resolution. Vacuum-outlet operation of a column with a gas chromatographic detector necessitates that the detector also be under vacuum. Simple modifications were made to a gas chromatograph-flame ionization detector (GC-FID) for vacuum-inlet and vacuum-outlet operation. The vacuum-inlet system was operated in the splitless mode to allow for efficient sample loading prior to operation at reduced pressures. The goal of FID operation at 100 torr or less was achieved by using oxygen in place of air and optimizing the gas flows under vacuum to maintain a stable flame at pressures as low as 46 torr. An outlet pressure of 85 torr with optimized gas flows allowed for routine operation of the FID without solvent flame-out. It was discovered that the sensitivity is enhanced compared to atmospheric operation over a range of outlet pressures from approximately 200 to 400 torr; however, operation of the FID at the lowest possible pressures decreases the analytical sensitivity due to both the outlet pressure and the absence of helium makeup gas

Differential neuroproteomic and systems biology analysis of spinal cord injury

Acute spinal cord injury (SCI) is a devastating condition with many consequences and no known effective treatment. Although it is quite easy to diagnose traumatic SCI, the assessment of injury severity and projection of disease progression or recovery are often challenging, as no consensus biomarkers have been clearly identified. Here rats were subjected to experimental moderate or severe thoracic SCI. At 24h and 7d postinjury, spinal cord segment caudal to injury center versus sham samples was harvested and subjected to differential proteomic analysis. Cationic/anionic-exchange chromatography, followed by 1D polyacrylamide gel electrophoresis, was used to reduce protein complexity. A reverse phase liquid chromatography-tandem mass spectrometry proteomic platform was then utilized to identify proteome changes associated with SCI. Twenty-two and 22 proteins were up-regulated at 24 h and 7 day after SCI, respectively; whereas 19 and 16 proteins are down-regulated at 24 h and 7 day after SCI, respectively, when compared with sham control. A subset of 12 proteins were identified as candidate SCI biomarkers - TF (Transferrin), FASN (Fatty acid synthase), NME1 (Nucleoside diphosphate kinase 1), STMN1 (Stathmin 1), EEF2 (Eukaryotic translation elongation factor 2), CTSD (Cathepsin D), ANXA1 (Annexin A1), ANXA2 (Annexin A2), PGM1 (Phosphoglucomutase 1), PEA15 (Phosphoprotein enriched in astrocytes 15), GOT2 (Glutamic-oxaloacetic transaminase 2), and TPI-1 (Triosephosphate isomerase 1), data are available via ProteomeXchange with identifier PXD003473. In addition, Transferrin, Cathepsin D, and TPI-1 and PEA15 were further verified in rat spinal cord tissue and/or CSF samples after SCI and in human CSF samples from moderate/severe SCI patients. Lastly, a systems biology approach was utilized to determine the critical biochemical pathways and interactome in the pathogenesis of SCI. Thus, SCI candidate biomarkers identified can be used to correlate with disease progression or to identify potential SCI therapeutic targets

Estimation of Mutagenic/Carcinogenic potential of environmental contaminants by ion-molecule reactions and tandem mass spectrometry

AbstractThe ability to produce and detect products of model DNA/carcinogen ion-molecule reactions is demonstrated in the ion source and the collision cell of a triple quadrupole tandem mass spectrometer. Reaction between adenine and benzoyl chloride in the ion source is shown to produce the DNA adduct benzoyl adenine. The daughter ion mass spectrum of the reaction product is compared to that of the synthesized standard. Mass chromatograms of the reaction between mass-selected pyridine ions and various analytes eluting from a GC column into the collision cell are demonstrated and illustrate the ability to detect only the GC eluates that react with pyridine. This technique could provide a rapid and sensitive method for screening complex environmental samples for carcinogens, as well as for estimating the relative mutagenic/carcinogenic potential of environmental contaminants

Singlet fission efficiency in tetracene-based organic solar cells

Singlet exciton fission splits one singlet exciton into two triplet excitons. Using a joint analysis of photocurrent and fluorescence modulation under a magnetic field, we determine that the triplet yield within optimized tetracene organic photovoltaic devices is 153% ± 5% for a tetracene film thickness of 20 nm. The corresponding internal quantum efficiency is 127% ± 18%. These results are used to prove the effectiveness of a simplified triplet yield measurement that relies only on the magnetic field modulation of fluorescence. Despite its relatively slow rate of singlet fission, the measured triplet yields confirm that tetracene is presently the best candidate for use with silicon solar cells.United States. Dept. of Energy. Office of Basic Energy Sciences (Award DE-SC0001088)National Science Foundation (U.S.). Graduate Research Fellowship (Grant 1122374

Comparing SF-36 scores across three groups of women with different health profiles

Background: The widespread use of the Medical Outcomes Study (MOS) 36-item Short-Form Health Survey (SF-36) facilitates the comparison of health-related quality of life (HRQL) across independent studies. Objectives : To compare the scores of eight scales and two summary scales of the SF-36 across participants in the Women’s Healthy Eating and Living (WHEL) trial, the Women’s Health Initiative-Dietary Modification trial (WHI-DM), and the MOS, and to illustrate the use of effect sizes for interpreting the importance of group differences. Methods : WHEL and WHI-DM are both multi-center dietary interventions; only data from the UC Davis sites were used in our study. WHEL participants had a recent history of breast cancer, WHI-DM participants were healthy, postmenopausal women, and women in the MOS had a history of hypertension, diabetes, heart disease, or depression. General linear models were used to identify statistically significant differences in scale scores. Meaningful differences were determined by effect sizes computed using a common within-group standard deviation (SD) and SDs from normative data. Results : After adjusting for age and marital status, SF-36 scores for the WHI-DM and WHEL samples were similar and both had statistically significantly higher scores than the MOS sample. Relative to the WHEL or WHI-DM studies, MOS scores for scales related to the physical domain were clearly meaningfully lower whereas scale scores related to the mental health domain were potentially meaningfully lower. Conclusions : The HRQL of breast cancer survivors is comparable to that of healthy women and better than that of women with chronic health conditions, particularly with respect to physical health. This study illustrated the use of ranges of effects sizes for aiding the interpretation of SF-36 scores differences across independent studies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43569/1/11136_2004_Article_6673.pd

Ursinus College Alumni Journal, November 1956

Industrial aid to education increases • Evening School growing • President N. E. McClure receives honorary degree • Notes from the Dean\u27s office • Messiah presentation • Dr. Alfred L. Creager Founders\u27 Day speaker • Professor Witmer dies • New faculty salary scale effective • Notes from the office of the Dean of Women • Faculty corner • Ursinus forum • Dormitory construction proceeding rapidly • Old Timers\u27 Day successful • York alumni hold summer meeting • 1956 Loyalty Fund report • Women\u27s Club project • Old Timers\u27 Day committee • Superior Tube Company awards scholarship • Notes from the Office of Admissions • Curtain Club presents Our Town • Sports: Alumnae hockey; Ursinus boosters; 1956 soccer prospects; Varsity hockey • News about ourselves • New associate members • Births • Weddings • Necrology • Ursinus Women\u27s Club • Notes from the librarian • Rotary Club gives Ursinus scholarship • Gros and Dawkins are awarded WAA blazershttps://digitalcommons.ursinus.edu/alumnijournal/1057/thumbnail.jp

The Ursinus Weekly, May 7, 1951

Bill LeKernec to edit next year\u27s Lantern • Sororities elect new officers, plan events • Varsity banquet tonight • W. A. A. holds election • Y members plan 1951-52 activities at camp retreat • Campus ready for May Day; Pageant, play to be big events • Professors tackle broad questions in first panel • YM-YW name cabinet, heads of commission • Graduation announcements available to seniors • Students cast primary votes for officers • Election of Curtain Club officers listed • Chi Alpha to elect • Editorials: System a success • Making of foreign policy • Letters to the editor • Three officials embroiled • Ursinus mentioned in Gramercy Ghost • May Day histories reveal variety of festivities • Weekly scribe sheds light on life of famous Ursinus College athlete • Local lassies win 4-1 over Rosemont • Interfraternity track meet to begin this Wednesday • Temple women defeat local tennis squad on May 2 • Cindermen win as Eshbach, Scheirer and Loomis are double winners • Bears capitalize on four hits to beat Garnet • Moravian, Elizabethtown suffer as netmen extend streak to four • Ursinus enters three in intercollege tennis • Bearettes shut-out Albright squad • Lincoln nine halts rally to defeat Grizzlies, 6 to 3 • Curtis clinches first place slots in both leagues • Women\u27s softball team defeats Drexel, Temple • Forum speaker tells of Turkey\u27s position • Dr. Rice invited to Washington for Atlantic Union Conference • Ann Knaur elected President of French Club • Rec center party planned • Women day students hold senior dinner • Supper tickets on sale • Chess Club ends successful season • Shaw named prexyhttps://digitalcommons.ursinus.edu/weekly/1568/thumbnail.jp