Sample size determination for the parallel model in a survey with sensitive questions

Recently, a new non-randomized parallel design is proposed by Tian (2013) for surveys with sensitive topics. However, the sample size formulae associated with testing hypotheses for the parallel model are not yet available. As a crucial component in surveys, the sample size formulae with the parallel design are developed in this paper by using the power analysis method for both the one- and two-sample problems. We consider both the one- and two-sample problems. The asymptotic power functions and the corresponding sample size formulae for both the one- and two-sided tests based on the large-sample normal approximation are derived. The performance is assessed through comparing the asymptotic power with the exact power and reporting the ratio of the sample sizes with the parallel model and the design of direct questioning. We numerically compare the sample sizes needed for the parallel design with those required for the crosswise and triangular models. Two theoretical justifications are also provided. An example from a survey on ‘sexual practices’ in San Francisco, Las Vegas and Portland is used to illustrate the proposed methods.postprin

A geometrical theory for {111} <hkl> recrystallisation texture formation in cold rolled IF steel

The introduction of a conditional deformating banding into BCC rolling texture modellling has produced a clue as too the origins of the {111} texture as it develops from the γ fibre material. OIM has reveqaled that deformation bands are present in many deformed γ grains, which therefore produced the gometrical condition for successful nucleation of rotated ND material by either subgrain growth or SIBM. Clearly the roles of solutes and precipitates have to be established in this deformation microstructure.published_or_final_versio

Melatonin Attenuates Intermittent Hypoxia-Induced Lipid Peroxidation and Local Inflammation in Rat Adrenal Medulla

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Hydrocarbon ratios during PEM-WEST A: A model perspective

A useful application of the hydrocarbon measurements collected during the Pacific Exploratory Mission (PEM-West A) is as markers or indices of atmospheric processing. Traditionally, ratios of particular hydrocarbons have been interpreted as photochemical indices, since much of the effect due to atmospheric transport is assumed to cancel by using ratios. However, an ever increasing body of observatonial and theoretical evidence suggests that turbulent mixing associated with atmospheric transport influences certain hydrocarbon ratios significantly. In this study a three-dimensional mesoscale photochemical model is used to study the interaction of photochemistry and atmospheric mixing on select hydrocarbons. In terms of correlations and functional relationships between various alkanes the model results and PEM-West A hydrocarbon observations share many similar characteristics as well as explainable differences. When the three-dimensional model is applied to inert tracers, hydrocarbon ratios and other relationships exactly follow those expected by simple dilution with model-imposed "background air," and the three-dimensional results for reactive hydrocarbons are quite consistent with a combined influence of photochemistry and simple dilution. Analogous to these model results, relationships between various hydrocarbons collected during the PEM-West A experiment appear to be consistent with this simplified picture of photochemistry and dilution affecting individual air masses. When hydrocarbons are chosen that have negligeble contributions to clean background air, unambiguous determinations of the relative contributions to photochemistry and dilution can be estimated from the hydrocarbon samples. Both the three-dimensional model results and the observations imply an average characteristic lifetime for dilution with background air roughly equivalent to the photochemical lifetime of butane for the western Pacific lower troposphere. Moreover, the dominance of OH as the primary photochemical oxidant downwind of anthropogenic source regions can be inferred from correlations between the highly reactive alkane ratios. By incorporating back-trajectory information within the three-dimensional model analysis, a correspondence between time and a particular hydrocarbon or hydrocarbon ratio can be determined, and the influence of atmospheric mixing or photochemistry can be quantified. Results of the three-dimensional model study are compared and applied to the PEM-West A hydrocarbon dataset, yielding a practical methodology for determining average OH concentrations and atmospheric mixing rates from the hydrocarbon measurements. Aircraft data taken below 2 km during wall flights east of Japan imply a diurnal average OH concentration of ∼3 × 106 cm-3. The characteristic time for dilution with background air is estimated to be ∼2.5 days for the two study areas examined in this work. Copyright 1996 by the American Geophysical Union

Nadph oxidase upregulated by AT1 receptor mediates chronic intermittent hypoxia-induced oxidative stress and inflammation in rat adrenal medulla

Poster PresentationOur previous study found that chronic intermittent hypoxia (CIH) associated with recurrent apnea induced oxidative stress and inflammation in rat adrenal medulla. However, the underline mechanism was not clear. We hypothesized that, under CIH, the up-regulation of NADPH oxidase mediated by renin-angiotensin system (RAS) via an activation of angiotensin II receptor 1 (AT1) might take part in the oxidative stress and local inflammation in the adrenal medulla. Adult male SD rats were exposed to air (normoxic) control or CIH treatment (8 hours/day) which mimicked a severe recurrent sleep apneic condition for 14 days. Oral feeding of Telmisartan (10 mg/kg), a specific AT1 receptor blocker, or an intraperitoneal injection of apocynin (25 mg/kg i.p.), an inhibitor of NADPH oxidase, or vehicle was performed before the daily hypoxic treatment. The adrenal medulla was harvested for the measurement of markers for oxidative stress (MDA and NTR), macrophages infiltration (ED1), apoptosis, and inflammation (pro-inflammatory mediators) using TUNEL assay, real-time PCR, ELISA and Western blot. Levels of MDA and NTR were significantly increased in the hypoxic (CIH) group when compared with the normoxic control, but were normalized in the hypoxic groups treated with apocynin (AIH) or telmisartan (TIH). The expression levels of macrophage marker ED1-immunoreactivity and the pro-inflammatory mediators (TNFa, IL6) were also elevated in the CIH group, but were significantly ameliorated by the apocynin or telmisartan treatment. In addition, the amount of apoptotic cells in the CIH group was significantly higher than that of the AIH and TIH groups. Moreover, the mRNA levels of NADPH oxidase subunits (Nox2, Nox4) were increased significantly in the CIH group when compared with that of the AIH and TIH groups. Also, the protein expression of RAS components (AGT, AT1) was also increased in the CIH group. In conclusion, we showed that an up-regulation of NADPH oxidase via AT1 receptor activation mediates CIH-induced oxidative stress and inflammation in rat adrenal medulla.published_or_final_versio

Low-temperature switching fatigue behavior of ferroelectric SrBi₂Ta₂O[sub 9] thin films

Author name used in this publication: Z. G. LiuAuthor name used in this publication: H. L. W. ChanAuthor name used in this publication: C. L. Choy2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Lycium barbarum polysaccharide attenuates alcoholic cellular injury through TXNIP-NLRP3 inflammasome pathway

postprin

Correlation between primary phases and atomic clusters in a Zr-based metallic glass

2010-2011 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Combined acoustic radiation force impulse, aminotransferase to platelet ratio index and Forns index assessment for hepatic fibrosis grading in hepatitis B

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