920 research outputs found
The NYU Survey Service: Promoting Value in Undergraduate Education
New York University\u27s Data Service Studio has recently launched the NYU Survey Service, whose ultimate aim is to support the development and administration of surveys of all types. For the web-based component, we utilize a product called Qualtrics, which allows university affiliates to develop and administer web-based surveys. This article describes the process by which we at NYU came to offer the service during a time when concerns abound about the ability of libraries to support and expand services while still meeting service imperatives such as robust data services. While many considerations went into this evaluation and the ultimate conclusion to pilot the service, we emphasize those most related to data and information literacy, undergraduate instruction, learning and research, library collaborations and application administration and support
CII* Absorption in Damped Lyman Alpha Systems: (II) A New Window on the Star Formation History of the Universe
Starting from the SFR per unit physical area, determined for DLAs using the C
II* method, we obtain the SFR per unit comoving volume at 3, and
find that it agrees with that for the Lyman Break Galaxies (LBGs). Though the
mass of produced stars indicated by the SFRs is consistent with the current
densities of known stellar populations, the mass of metals produced by =2.5
is 30 times larger than detected in absorption in DLAs. The most likely
solutions to this ``missing metals'' problem is that star formation occurs in
compact bulge regions. We search for evidence of feedback and find no
correlations between the SFR per unit area and N(H I), but possible
correlations between SFR per unit area and low-ion velocity width and SFR per
unit area and metal abundance. We show that (a) the correlation between cooling
rate and dust-to-gas ratio is positive evidence for grain photoelectric
heating, (b) the CMB does not significantly populate the C II excited
fine-structure states, and (c) the ratio of CII* to resonance-line optical
depths is a sensitive probe of the multi-phase structure of the DLA gas. We
address recent arguments that DLAs are comprised only of WNM gas, and show them
to be inconclusive. Despite the rough agreement between SFR per unit comoving
volume for DLAs and LBGs, current evidence indicates these are distinct
populations
Metabolic Profiling of IDH Mutation and Malignant Progression in Infiltrating Glioma.
Infiltrating low grade gliomas (LGGs) are heterogeneous in their behavior and the strategies used for clinical management are highly variable. A key factor in clinical decision-making is that patients with mutations in the isocitrate dehydrogenase 1 and 2 (IDH1/2) oncogenes are more likely to have a favorable outcome and be sensitive to treatment. Because of their relatively long overall median survival, more aggressive treatments are typically reserved for patients that have undergone malignant progression (MP) to an anaplastic glioma or secondary glioblastoma (GBM). In the current study, ex vivo metabolic profiles of image-guided tissue samples obtained from patients with newly diagnosed and recurrent LGG were investigated using proton high-resolution magic angle spinning spectroscopy (1H HR-MAS). Distinct spectral profiles were observed for lesions with IDH-mutated genotypes, between astrocytoma and oligodendroglioma histologies, as well as for tumors that had undergone MP. Levels of 2-hydroxyglutarate (2HG) were correlated with increased mitotic activity, axonal disruption, vascular neoplasia, and with several brain metabolites including the choline species, glutamate, glutathione, and GABA. The information obtained in this study may be used to develop strategies for in vivo characterization of infiltrative glioma, in order to improve disease stratification and to assist in monitoring response to therapy
Economic evaluation of short treatment for multidrugresistant tuberculosis, Ethiopia and South Africa : the STREAM trial
OBJECTIVE
STREAM was a phase-III non-inferiority randomised controlled trial (RCT) to evaluate a shortened regimen for multi-drug resistant tuberculosis (MDR-TB), and included the first-ever within-trial economic evaluation of such regimens, reported here.
METHODS
We compared the costs of âLongâ (20-22 months) and âShortâ (9-11 months) regimens in Ethiopia and South Africa. Cost data were collected from trial participants, and health system costs estimated using âbottom-upâ and âtop-downâ costing approaches. A cost-effectiveness analysis was conducted with the trial primary outcome as the measure of effectiveness, including a probabilistic sensitivity analysis (PSA) to illustrate decision uncertainty.
FINDINGS
The Short-regimen reduced healthcare costs per case by 21% in South Africa (US6,619 Short) and 25% in Ethiopia (US4,552 Short). The largest component of this saving was medication in South Africa (67%) and social support in Ethiopia (35%). In Ethiopia, participants on the Short-regimen reported reductions in dietary supplementation expenditure (US13 (95%CI 11-14), South Africa US19,000 (Ethiopia) or <US$14,500 (South Africa).
CONCLUSION
The Short-regimen provided substantial health system cost savings and reduced financial burden on participants. Shorter regimens are likely to be cost-effective in most settings, and an effective strategy to support the WHO goal of eliminating catastrophic costs in T
Accurate PCR detection of influenza A/B and respiratory syncytial viruses by use of Cepheid Xpert Flu+RSV Xpress Assay in point-of-care settings: Comparison to Prodesse ProFlu+
ABSTRACT
The Xpert Flu+RSV Xpress Assay is a fast, automated
in vitro
diagnostic test for qualitative detection and differentiation of influenza A and B viruses and respiratory syncytial virus (RSV) performed on the Cepheid GeneXpert Xpress System. The objective of this study was to establish performance characteristics of the Xpert Flu+RSV Xpress Assay compared to those of the Prodesse ProFlu+ real-time reverse transcription-PCR (RT-PCR) assay (ProFlu+) for the detection of influenza A and B viruses as well as RSV in a Clinical Laboratory Improvement Amendments (CLIA)-waived (CW) setting. Overall, the assay, using fresh and frozen nasopharyngeal (NP) swabs, demonstrated high concordance with results of the ProFlu+ assay in the combined CW and non-CW settings with positive percent agreements (PPA) (100%, 100%, and 97.1%) and negative percent agreements (NPA) (95.2%, 99.5%, and 99.6%) for influenza A and B viruses and RSV, respectively. In conclusion, this multicenter study using the Cepheid Xpert Flu+RSV Xpress Assay demonstrated high sensitivities and specificities for influenza A and B viruses and RSV in âŒ60 min for use at the point-of-care in the CW setting.
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Restoration of rotational invariance of bound states on the light front
We study bound states in a model with scalar nucleons interacting via an
exchanged scalar meson using the Hamiltonian formalism on the light front. In
this approach manifest rotational invariance is broken when the Fock space is
truncated. By considering an effective Hamiltonian that takes into account two
meson exchanges, we find that this breaking of rotational invariance is
decreased from that which occurs when only one meson exchange is included. The
best improvement occurs when the states are weakly bound.Comment: 20 pages, 6 figures, uses feynMF; changed typos, clarified use of
angular momentu
Comparative analyses of proteins from Haemophilus influenzae biofilm and planktonic populations using metabolic labeling and mass spectrometry
BACKGROUND: Non-typeable H. influenzae (NTHi) is a nasopharyngeal commensal that can become an opportunistic pathogen causing infections such as otitis media, pneumonia, and bronchitis. NTHi is known to form biofilms. Resistance of bacterial biofilms to clearance by host defense mechanisms and antibiotic treatments is well-established. In the current study, we used stable isotope labeling by amino acids in cell culture (SILAC) to compare the proteomic profiles of NTHi biofilm and planktonic organisms. Duplicate continuous-flow growth chambers containing defined media with either âlightâ (L) isoleucine or âheavyâ (H) (13)C(6)-labeled isoleucine were used to grow planktonic (L) and biofilm (H) samples, respectively. Bacteria were removed from the chambers, mixed based on weight, and protein extracts were generated. Liquid chromatography-mass spectrometry (LC-MS) was performed on the tryptic peptides and 814 unique proteins were identified with 99% confidence. RESULTS: Comparisons of the NTHi biofilm to planktonic samples demonstrated that 127 proteins showed differential expression with p-values â€0.05. Pathway analysis demonstrated that proteins involved in energy metabolism, protein synthesis, and purine, pyrimidine, nucleoside, and nucleotide processes showed a general trend of downregulation in the biofilm compared to planktonic organisms. Conversely, proteins involved in transcription, DNA metabolism, and fatty acid and phospholipid metabolism showed a general trend of upregulation under biofilm conditions. Selected reaction monitoring (SRM)-MS was used to validate a subset of these proteins; among these were aerobic respiration control protein ArcA, NAD nucleotidase and heme-binding protein A. CONCLUSIONS: The present proteomic study indicates that the NTHi biofilm exists in a semi-dormant state with decreased energy metabolism and protein synthesis yet is still capable of managing oxidative stress and in acquiring necessary cofactors important for biofilm survival. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12866-014-0329-9) contains supplementary material, which is available to authorized users
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