492 research outputs found
Discussion of “Evaluating Non-GAAP Performance Measures in the REIT Industry”
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47663/1/11142_2004_Article_193017.pd
Discussion of “Accruals, Cash Flows and Equity Values”
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47685/1/11142_2004_Article_241882.pd
Discussion of: “Contextual Fundamental Analysis Through the Prediction of Extreme Returns”
Beneish, Lee and Tarpley (2000) represents one of a small, but growing number of studies that develop and test contextual fundamental analysis techniques. Such studies offer great promise for increasing our understanding of the role of accounting information in evaluating firm performance. However, these studies also introduce their own unique research design issues. In this paper, I discuss the opportunities and research design issues facing this new line of research, using Beneish, Lee and Tarpley to illustrate my points.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47709/1/11142_2004_Article_354417.pd
Identification of an env-defective HIV-1 mutant capable of spontaneous reversion to a wild-type phenotype in certain T-cell lines
BACKGROUND: Attempts to eradicate HIV from cellular reservoirs are vital but depend on a clear understanding of how viral variants are transmitted and survive in the different cell types that constitute such reservoirs. Mutations in the env gene of HIV may be able to exert a differential influence on viral transmission ability in regard to cell-free and cell-associated viral forms. METHODS: The ability of HIV containing an env G367R mutation in cell-free and cell-associated viruses to cause infection and to revert to wild-type was measured using several T cell lines. To determine factors that might potentially influence the reversion of G367R, we studied each of entry inhibitors, inhibitors of cellular endocytosis, and modulators of cell growth and activation. RESULTS: We demonstrate that an HIV-1 variant containing a G367R substitution within the CD4 binding site of gp120 was non-infectious as free virus in culture but was infectious when infected cells were co-cultured with certain T cell lines or when cells were transfected by a relevant proviral plasmid. Differences in viral infectivity by cell-associated G367R viruses were determined by the type of target cell employed, regardless which type of donor cell was used. Reversion was slowed or inhibited by entry inhibitors and by inhibitors of cellular endocytosis. Interleukin 2 was able to block G367R reversion in only one of the T cell lines studied but not in the other, while phorbol 12-myristate 13-acetate (PMA) inhibited G367R reversion in all the T cell lines. CONCLUSIONS: Env-defective HIV may have a different phenotype as cell-free versus cell-associated virus. The persistence of defective forms can potentially lead to the emergence of virulent forms. The heterogeneity of cell types that constitute the HIV reservoir can contribute to viral variability, even among similar types of cells. This is the first demonstration of a mutation in the HIV envelope, i.e. G367R, that can compromise infection by cell-free virus but less severely by cell-associated virus and that does so in a cell type-dependent manner
Implied Equity Duration: A New Measure of Equity Risk
Duration is an important and well-established risk characteristic for fixed income securities. We use recent developments in financial statement analysis research to construct a measure of duration for equity securities. We find that the standard empirical predictions and results for fixed income securities extend to equity securities. We show that stock price volatility and stock beta are both positively correlated with equity duration. Moreover, estimates of common shocks to expected equity returns extracted using our measure of equity duration capture a strong common factor in stock returns. Additional analysis shows that the book-to-market ratio provides a crude measure of equity duration and that our more refined measure of equity duration subsumes the Fama and French (1993) book-to-market factor in stock returns. Our research shows how structured financial statement analysis can be used to construct superior measures of equity security risk.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47748/1/11142_2004_Article_5272372.pd
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Clinic Blood Pressure Underestimates Ambulatory Blood Pressure in an Untreated Employer-Based US Population: Results From the Masked Hypertension Study
Background: Ambulatory blood pressure (ABP) is consistently superior to clinic blood pressure (CBP) as a predictor of cardiovascular morbidity and mortality risk. A common perception is that ABP is usually lower than CBP. The relationship of the CBP minus ABP difference to age has not been examined in the United States.
Methods: Between 2005 and 2012, 888 healthy, employed, middle-aged (mean±SD age, 45±10.4 years) individuals (59% female, 7.4% black, 12% Hispanic) with screening BP <160/105 mm Hg and not taking antihypertensive medication completed 3 separate clinic BP assessments and a 24-hour ABP recording for the Masked Hypertension Study. The distributions of CBP, mean awake ABP (aABP), and the CBP−aABP difference in the full sample and by demographic characteristics were compared. Locally weighted scatterplot smoothing was used to model the relationship of the BP measures to age and body mass index. The prevalence of discrepancies in ABP- versus CBP-defined hypertension status—white-coat hypertension and masked hypertension—were also examined.
Results: Average systolic/diastolic aABP (123.0/77.4±10.3/7.4 mm Hg) was significantly higher than the average of 9 CBP readings over 3 visits (116.0/75.4±11.6/7.7 mm Hg). aABP exceeded CBP by >10 mm Hg much more frequently than CBP exceeded aABP. The difference (aABP>CBP) was most pronounced in young adults and those with normal body mass index. The systolic difference progressively diminished, but did not disappear, at older ages and higher body mass indexes. The diastolic difference vanished around age 65 and reversed (CBP>aABP) for body mass index >32.5 kg/m2. Whereas 5.3% of participants were hypertensive by CBP, 19.2% were hypertensive by aABP; 15.7% of those with nonelevated CBP had masked hypertension.
Conclusions: Contrary to a widely held belief, based primarily on cohort studies of patients with elevated CBP, ABP is not usually lower than CBP, at least not among healthy, employed individuals. Furthermore, a substantial proportion of otherwise healthy individuals with nonelevated CBP have masked hypertension. Demonstrated CBP−aABP gradients, if confirmed in representative samples (eg, NHANES [National Health and Nutrition Examination Survey]), could provide guidance for primary care physicians as to when, for a given CBP, 24-hour ABP would be useful to identify or rule out masked hypertension
Тепловой баланс помещения с электрической кабельной системой отопления
Solvothermal
oxidation of metallic gallium in monoethanolamine for 72 h at 240
°C yields a crystalline sample of γ-Ga<sub>2</sub>O<sub>3</sub> (∼30 nm crystallites). While Rietveld refinement (cubic
spinel structure, <i>Fd</i>3̅<i>m</i>; <i>a</i> = 8.23760(9) Å) reveals that Ga occupies two pairs
of octahedral and tetrahedral sites (ideal spinel and nonspinel),
it provides no information about their local distribution, which cannot
be statistical owing to the short Ga–Ga contacts produced if
neighboring ideal spinel and nonspinel sites are simultaneously occupied.
To create an atomistic model to reconcile this situation, a 6 ×
6 × 6 supercell of the crystal structure is constructed and refined
against neutron total scattering data using a reverse Monte Carlo
(RMC) approach. This accounts well for the local as well as long-range
structure and reveals significant local distortion in the octahedral
sites that resembles the structure of thermodynamically stable β-Ga<sub>2</sub>O<sub>3</sub>. <sup>71</sup>Ga solid-state NMR results reveal
a octahedral:tetrahedral Ga ratio that is consistent with the model
obtained from RMC. Nanocrystalline samples of γ-Ga<sub>2</sub>O<sub>3</sub> are produced by either a short solvothermal reaction
(240 °C for 11 h in diethanolamine; ∼15 nm crystallites)
or by precipitation from an ethanolic solution of gallium nitrate
(∼5 nm crystallites). For these samples, the Bragg scattering
profile is broadened by their smaller crystallite size, consistent
with transmission electron microscopy results, and analysis of the
relative Bragg peak intensities provides evidence that a greater proportion
of tetrahedral versus octahedral sites are filled. In contrast, neutron
total scattering shows the same average Ga–O distance with
decreasing particle size, consistent with <sup>71</sup>Ga solid-state
NMR results that indicate that all samples contain the same overall
proportion of octahedral:tetrahedral Ga. It is postulated that increased
occupation of tetrahedral sites within the smaller crystallites is
balanced by an increased proportion of octahedral surface Ga sites,
owing to termination by bound solvent or hydroxide
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Individualized decision aid for diverse women with lupus nephritis (IDEA-WON): A randomized controlled trial.
BackgroundTreatment decision-making regarding immunosuppressive therapy is challenging for individuals with lupus. We assessed the effectiveness of a decision aid for immunosuppressive therapy in lupus nephritis.Methods and findingsIn a United States multicenter, open-label, randomized controlled trial (RCT), adult women with lupus nephritis, mostly from racial/ethnic minority backgrounds with low socioeconomic status (SES), seen in in- or outpatient settings, were randomized to an individualized, culturally tailored, computerized decision aid versus American College of Rheumatology (ACR) lupus pamphlet (1:1 ratio), using computer-generated randomization. We hypothesized that the co-primary outcomes of decisional conflict and informed choice regarding immunosuppressive medications would improve more in the decision aid group. Of 301 randomized women, 298 were analyzed; 47% were African-American, 26% Hispanic, and 15% white. Mean age (standard deviation [SD]) was 37 (12) years, 57% had annual income of <$40,000, and 36% had a high school education or less. Compared with the provision of the ACR lupus pamphlet (n = 147), participants randomized to the decision aid (n = 151) had (1) a clinically meaningful and statistically significant reduction in decisional conflict, 21.8 (standard error [SE], 2.5) versus 12.7 (SE, 2.0; p = 0.005) and (2) no difference in informed choice in the main analysis, 41% versus 31% (p = 0.08), but clinically meaningful and statistically significant difference in sensitivity analysis (net values for immunosuppressives positive [in favor] versus negative [against]), 50% versus 35% (p = 0.006). Unresolved decisional conflict was lower in the decision aid versus pamphlet groups, 22% versus 44% (p < 0.001). Significantly more patients in the decision aid versus pamphlet group rated information to be excellent for understanding lupus nephritis (49% versus 33%), risk factors (43% versus 27%), medication options (50% versus 33%; p ≤ 0.003 for all); and the ease of use of materials was higher in the decision aid versus pamphlet groups (51% versus 38%; p = 0.006). Key study limitations were the exclusion of men, short follow-up, and the lack of clinical outcomes, including medication adherence.ConclusionsAn individualized decision aid was more effective than usual care in reducing decisional conflict for choice of immunosuppressive medications in women with lupus nephritis.Trial registrationClinicaltrials.gov, NCT02319525
Evaluation of Human Papilloma Virus Diagnostic Testing in Oropharyngeal Squamous Cell Carcinoma: Sensitivity, Specificity, and Prognostic Discrimination
Abstract Purpose: Human papillomavirus-16 (HPV16) is the causative agent in a biologically distinct subset of oropharyngeal squamous cell carcinoma (OPSCC) with highly favorable prognosis. In clinical trials, HPV16 status is an essential inclusion or stratification parameter, highlighting the importance of accurate testing. Experimental Design: Fixed and fresh-frozen tissue from 108 OPSCC cases were subject to eight possible assay/assay combinations: p16 immunohistochemistry (p16 IHC); in situ hybridization for high-risk HPV (HR HPV ISH); quantitative PCR (qPCR) for both viral E6 RNA (RNA qPCR) and DNA (DNA qPCR); and combinations of the above. Results: HPV16-positive OPSCC presented in younger patients (mean 7.5 years younger, P = 0.003) who smoked less than HPV-negative patients (P = 0.007). The proportion of HPV16-positive cases increased from 15% to 57% (P = 0.001) between 1988 and 2009. A combination of p16 IHC/DNA qPCR showed acceptable sensitivity (97%) and specificity (94%) compared with the RNA qPCR “gold standard”, as well as being the best discriminator of favorable outcome (overall survival P = 0.002). p16 IHC/HR HPV ISH also had acceptable specificity (90%) but the substantial reduction in its sensitivity (88%) impacted upon its prognostic value (P = 0.02). p16 IHC, HR HPV ISH, or DNA qPCR was not sufficiently specific to recommend in clinical trials when used in isolation. Conclusions: Caution must be exercised in applying HPV16 diagnostic tests because of significant disparities in accuracy and prognostic value in previously published techniques. Clin Cancer Res; 17(19); 6262–71. ©2011 AACR.</jats:p
Molecules and Dust Grains in AGB Stars in Nearby Galaxies—the Influence of Metallicities
Original paper can be found at: http://scitation.aip.org/proceedings/confproceed/948.jsp Copyright AIP. DOI: 10.1063/1.2818993 [Full text of this paper is not available in the UHRA]We have obtained infrared spectra of carbon stars in four nearby galaxies—the Large and Small Magellanic Clouds, the Sagittarius dwarf spheroidal galaxy, and the Fornax dwarf spheroidal galaxy. Our primary aim is to investigate mass-loss rate and molecular bands of these stars as a function of metallicity, by comparing AGB stars in several galaxies with different metallicities. These stars were observed using the Infrared Spectrometer (IRS) onboard the Spitzer Space Telescope which covers 5–35 µm region, and the Infrared Spectrometer And Array Camera (ISAAC) on the Very Large Telescope which covers the 2.9–4.1 µm region. HCN, CH and C2H2 molecular bands, as well as SiC and MgS dust features are identified in the spectra. We find no evidence that mass-loss rates depend on metallicity. Carbon stars are strongly affected by carbon production during the AGB phase; primarily mass-loss of carbon-rich stars are driven by amorphous carbon dust grains, which explains the little metallicity dependence of mass-loss rate for carbon-rich stars. We found that C2H2 bands are prominent features at 3–15 µm among extragalactic carbon stars, which is not always the case for Galactic carbon stars. We argue that the difference is caused by systematically high C/O ratios in low-metallicity environments.otherPeer reviewe
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