1,238 research outputs found
The c2d Spitzer Spectroscopic Survey of Ices Around Low-Mass Young Stellar Objects. IV. NH3 and CH3OH
NH3 and CH3OH are key molecules in astrochemical networks leading to the
formation of more complex N- and O-bearing molecules, such as CH3CN and
HCOOCH3. Despite a number of recent studies, little is known about their
abundances in the solid state. (...) In this work, we investigate the ~ 8-10
micron region in the Spitzer IRS (InfraRed Spectrograph) spectra of 41 low-mass
young stellar objects (YSOs). These data are part of a survey of interstellar
ices in a sample of low-mass YSOs studied in earlier papers in this series. We
used both an empirical and a local continuum method to correct for the
contribution from the 10 micron silicate absorption in the recorded spectra. In
addition, we conducted a systematic laboratory study of NH3- and
CH3OH-containing ices to help interpret the astronomical spectra. We clearly
detect a feature at ~9 micron in 24 low-mass YSOs. Within the uncertainty in
continuum determination, we identify this feature with the NH3 nu_2 umbrella
mode, and derive abundances with respect to water between ~2 and 15%.
Simultaneously, we also revisited the case of CH3OH ice by studying the nu_4
C-O stretch mode of this molecule at ~9.7 micron in 16 objects, yielding
abundances consistent with those derived by Boogert et al. 2008 (hereafter
paper I) based on a simultaneous 9.75 and 3.53 micron data analysis. Our study
indicates that NH3 is present primarily in H2O-rich ices, but that in some
cases, such ices are insufficient to explain the observed narrow FWHM. The
laboratory data point to CH3OH being in an almost pure methanol ice, or mixed
mainly with CO or CO2, consistent with its formation through hydrogenation on
grains. Finally, we use our derived NH3 abundances in combination with
previously published abundances of other solid N-bearing species to find that
up to 10-20 % of nitrogen is locked up in known ices.Comment: 31 pages, 15 figures, accepted for publication in Ap
Diagnostic Accuracy of Fine Needle Biopsy for Metastatic Melanoma and Its Implications for Patient Management
The use of fine needle biopsy (FNB) for the diagnosis of metastatic melanoma can lead to the early removal and treatment of metastases, reduce the frequency of unnecessary surgery, and facilitate the staging of patients enrolled in clinical trials of adjuvant therapies. In this study, the accuracy of FNB for the diagnosis of metastatic melanoma was investigated. A retrospective cohort study was performed with 2204 consecutive FNBs performed on 1416 patients known or suspected to have metastatic melanoma. Almost three-quarters (1582) of these FNBs were verified by either histopathologic diagnosis following surgical resection or clinical follow-up. FNB for metastatic melanoma was found to have an overall sensitivity of 92.1% and a specificity of 99.2%, with 69 false-negative and 5 false-positive findings identified. The sensitivity of the procedure was found to be influenced by six factors. The use of immunostains, reporting of the specimen by a cytopathologist who had reported >500 cases, lesions located in the skin and subcutis, and patients with ulcerated primary melanomas were factors associated with a significant improvement in the sensitivity of the test. However, FNBs performed in masses located in lymph nodes of the axilla and FNBs that required more than one needle pass to obtain a sample were far more likely to result in false-negative results. FNB is a rapid, accurate, and clinically useful technique for the assessment of disease status in patients with suspected metastatic melanoma
Attentional differences in a driving hazard perception task in adults with autism spectrum disorders
The current study explored attentional processing of social and non social stimuli in ASD within the context of a driving hazard perception task. Participants watched videos of road scenes and detected hazards while their eye movements were recorded. Although individuals with ASD demonstrated relatively good detection of driving hazards, they were slower to orient to hazards. Greater attentional capture in the time preceding the hazards’ onset was associated with lower verbal IQ. The findings suggest that individuals with ASD may distribute and direct their attention diferently when identifying driving hazards
The relationship between dietary fat intake and risk of colorectal cancer: evidence from the combined analysis of 13 case-control studies
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.Facultad de Ciencias Médica
Personalized Drug Dosage – Closing the Loop
A brief account is given of various approaches
to the individualization of drug dosage, including the use of
pharmacodynamic markers, therapeutic monitoring of plasma
drug concentrations, genotyping, computer-guided dosage
using ‘dashboards’, and automatic closed-loop control of
pharmacological action. The potential for linking the real patient
to his or her ‘virtual twin’ through the application of
physiologically-based pharmacokinetic modeling is also
discussed
A base-free synthetic route to anti-bimetallic lanthanide pentalene complexes
We report the synthesis and structural characterisation of three homobimetallic complexes featuring divalent lanthanide metals (Ln = Yb, Eu and Sm) bridged by the silylated pentalene ligand [1,4-{SiiPr3}2C8H4]2− (= Pn†). Magnetic measurements and cyclic voltammetry have been used to investigate the extent of intermetallic communication in these systems, in the context of molecular models for organolanthanide based conducting materials
Vaccinia virus protein C16 acts intracellularly to modulate the host response and promote virulence
The vaccinia virus (VACV) strain Western Reserve C16 protein has been characterized and its effects on virus replication and virulence have been determined. The C16L gene is present in the inverted terminal repeat and so is one of the few VACV genes that are diploid. The C16 protein is highly conserved between different VACV strains, and also in the orthopoxviruses variola virus, ectromelia virus, horsepox virus and cowpox virus. C16 is a 37.5 kDa protein, which is expressed early during infection and localizes to the cell nucleus and cytoplasm of infected and transfected cells. The loss of the C16L gene had no effect on virus growth kinetics but did reduce plaque size slightly. Furthermore, the virulence of a virus lacking C16L (vΔC16) was reduced in a murine intranasal model compared with control viruses and there were reduced virus titres from 4 days post-infection. In the absence of C16, the recruitment of inflammatory cells in the lung and bronchoalveolar lavage was increased early after infection (day 3) and more CD4+ and CD8+ T cells expressed the CD69 activation marker. Conversely, late after infection with vΔC16 (day 10) there were fewer T cells remaining, indicating more rapid clearance of infection. Collectively, these data indicate that C16 diminishes the immune response and is an intracellular immunomodulator
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1960
Recent Developments Affecting Golf Course Design (page 1) From the Editor (3) Five Year Results (3) Turf Management Club News (4) Quotes from 1960 Seniors (5) Poa annua - - Friend or Foe (6) The Horticulture Show (7) Cartoons (8) Message from the Winter School President of 1960 (10) The Most Outstanding Turf Senior for 1959 (10) The Value of the Proper Use of Lime (11) Summer Placement (12) A Greenhouse on the Golf Course (13) More Opportunities in the Future for the Aggressive Superintendent at Country Clubs (14) Soil, Sawdust and Turfgrass (15) Picture - Senior Stockbridge Turf majors (16) Picture - Freshman Stockbridge Turf majors (17) Susceptibility of Merion Bluegrass to Stripe Smut (18) Bents in the South (19) Picture - Honorary Members of Turf Management Club (20) Picture - Graduates of Winter School for Turf mangers- 1960 (21) Weather - We are Going to Have Weather, Whether or Not - What Should we Expect by O. Tennebaum & R. E. Lautzenheiser (A-1) The Nature of Winter Injury to Plants by Dr. Johnson Parker (A-1) Turf Problems: You Name it and We\u27ve Had It in \u2759 by Alexander Radko ad T.T. Taylor (A-3) Topdressing Experiences with Greens at Century by James Fulwider (A-5) Poa annua - Fairway Rennovation at winged Foot by Sherwood A. Moore (A-6) Winter Problems at Ekwanaok by Paul O\u27Leary (A-8) Progress Through Drainage by Kayem Ovian (A-10) Winter Injury on Home Lawns by Orlando Capizzi (A-12) The Status of Pre-emergence Chemicals for the Control of Crabgrass by Dr. E. Engel (A-12) Turf Nurseries - Establishment, Maintenance & Utilization by Robert Grant (A-14) Soil Compaction by Dr. R. B. Alderfer (A-16) Water Management Practices on Turf Areas by Dr. J.R. Watson (A-18) Getting to Know Your Members by Owen Griffith (A-23) New Trends in Clubhouse Landscaping by Alfred Boicourt (A-26) General Lawn Management (Alternate Session) Conserving Soil for a good Lawn by Dr. William G. Colby (A-27) Fertilizting and Liming by Dr. Joseph Steckel (A-28) Grasses and Grass Mixtures for New England Lawns by Dr. Robert Schery (A-29) The Care and Maintenance of Establishment Lawns by Dr. John R. Davi
Germline variation in inflammation-related pathways and risk of Barrett's oesophagus and oesophageal adenocarcinoma
Esophageal adenocarcinoma (EA) incidence has risen sharply in Western countries over recent decades. Local and systemic inflammation, operating downstream of disease-associated exposures, is considered an important contributor to EA pathogenesis. Several risk factors have been identified for EA and its precursor, Barrett’s esophagus (BE), including symptomatic reflux, obesity, and smoking. The role of inherited genetic susceptibility remains an area of active investigation. To explore whether germline variation related to inflammatory processes influences susceptibility to BE/EA, we used data from a genome-wide association study (GWAS) of 2,515 EA cases, 3,295 BE cases, and 3,207 controls. Our analysis included 7,863 single nucleotide polymorphisms (SNPs) in 449 genes assigned to five pathways: cyclooxygenase (COX), cytokine signaling, oxidative stress, human leukocyte antigen, and NFκB. A principal components-based analytic framework was employed to evaluate pathway-level and gene-level associations with disease risk. We identified a significant signal for the COX pathway in relation to BE risk (P=0.0059, FDR q=0.03), and in gene-level analyses found an association with MGST1 (microsomal glutathione-S-transferase 1; P=0.0005, q=0.005). Assessment of 36 MGST1 SNPs identified 14 variants associated with elevated BE risk (q<0.05). Of these, four were subsequently confirmed (P<5.5 × 10−5) in a meta-analysis encompassing an independent set of 1,851 BE cases and 3,496 controls. Three of these SNPs (rs3852575, rs73112090, rs4149204) were associated with similar elevations in EA risk. This study provides the most comprehensive evaluation of inflammation-related germline variation in relation to risk of BE/EA, and suggests that variants in MGST1 influence disease susceptibility
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