Although the ability to measure vertical eddy fluxes of gases from aircraft platforms represents an important capability to obtain spatially resolved data, accurate and reliable determination of the turbulent vertical velocity presents a great challenge. A nine-hole hemispherical probe known as the “Best Air Turbulence Probe” (often abbreviated as the “BAT Probe”) is frequently used in aircraft-based flux studies to sense the airflow angles and velocity relative to the aircraft. Instruments such as inertial navigation and global positioning systems allow the measured airflow to be converted into the three-dimensional wind velocity relative to the earth’s surface by taking into account the aircraft’s velocity and orientation. Calibration of the aircraft system has previously been performed primarily through in-flight experiments, where calibration coefficients were determined by performing various flight maneuvers. However, a rigorous test of the BAT Probe in a wind tunnel has not been previously undertaken. The authors summarize the results of a complement of low-speed wind tunnel tests and in-flight calibrations for the aircraft–BAT Probe combination. Two key factors are addressed in this paper: The first is the correction of systematic error arising from airflow measurements with a noncalibrated BAT Probe. The second is the instrumental precision in measuring the vertical component of wind from the integrated aircraft-based wind measurement system. The wind tunnel calibration allows one to ascertain the extent to which the BAT Probe airflow measurements depart from a commonly used theoretical potential flow model and to correct for systematic errors that would be present if only the potential flow model were used. The precision in the determined vertical winds was estimated by propagating the precision of the BAT Probe data (determined from the wind tunnel study) and the inertial measurement precision (determined from in-flight tests). The precision of the vertical wind measurement for spatial scales larger than approximately 2 m is independent of aircraft flight speed over the range of airspeeds studied, and the 1σ precision is approximately 0.03 m s−1.

) and organic nitrogen (DON) were measured in cloud water samples collected over the northern lower peninsula of Michigan. Within a given cloud field, several altitudes were sampled to examine changes in concentration and speciation with altitude. Several samples were analyzed for bacterial content and activity. Convective cumulus (cumulus congestus) were more concentrated than fair weather cumulus (cumulus humilis) for all major ions and DON, with the cloudy air DON concentrations in convective cumulus being twice as large as for fair weather cumulus, and for all other ions, the droplets were 4-6 times more concentrated. The molar average distribution of nitrogen in the cloud water was 43 (±10, 1s)% ammonium, 39 (±7)% nitrate and 18 (±11)% DON. High concentrations of bacteria were observed in the clouds with an average concentration of 2.9 Â 10 5 (±1.0 Â 10 5 , 1s) bacteria m À3 of cloudy air but which contributed less than 1% of the nitrogen in the cloud water. In addition, nitrifying bacteria were identified, indicating bacterial processing of nitrogen in the cloud water may occur. Air mass origin and altitude influence observed cloud water concentrations, with the exception of DON. The correlation of ammonium and sulfate, and calcium and nitrate suggest that ammonium sulfate and calcium nitrate aerosol may be important sources of these ions.

Recent research has made a strong case for the importance of NeuroIS methods for IS research. It has suggested that NeuroIS contributes to an improved explanation and prediction of IS phenomena. Yet, such research is unclear on the source of this improvement; while some studies indicate that NeuroIS constitutes an alternative to psychometrics, implying that the two methods assess the same dimension of an underlying IS construct, other studies indicate that NeuroIS constitutes a complement to psychometrics, implying that the two methods assess different dimensions of an IS construct. To clarify the role of NeuroIS in IS research and its contribution to IS research, in this study, we examine whether NeuroIS and psychometrics/psychological methods constitute alternatives or complements. We conduct this examination in the context of technostress, an emerging IS phenomenon to which both methods are relevant. We use the triangulation approach to explore the relationship between physiological and psychological/self-reported data. Using this approach, we argue that both kinds of data tap into different aspects of technostress and that, together, they can yield a more complete or holistic understanding of the impact of technostress on a theoretically-related outcome, rendering them complements. Then, we test this proposition empirically by probing the correlation between a psychological and a physiological measure of technostress in combination with an examination of their incremental validity in explaining performance on a computer-based task. The results show that the physiological stress measure (salivary alpha-amylase) explains and predicts variance in performance on the computer-based task over and above the prediction afforded by the self-reported stress measure. We conclude that NeuroIS is a critical complement to IS research.

Preference ratings are used to quantify quality of life in analyses used for health care policy making. Subjects indicated how many years of their life expectancy they would trade to avoid BRCA mutations, breast/ovarian cancer, and five preventive measures including prophylactic surgery, annual mammograms, and annual magnetic resonance imaging (MRI). Among 243 respondents, both the 83 women with mutations and the 160 controls rated mammography highest (most favorably), MRI next highest, having a child with a mutation lowest, and ovarian cancer next lowest. Controls rated prophylactic surgery higher than cancer (P < 0.01), but women with mutations did not. In logistic regression, controls were twice as willing as women with mutations to trade time except for screening modalities; younger, lower-income, and non-white women were more willing to trade time than older, higher-income, and white women. Our findings support the use of average-risk individuals' time trade-off preference ratings for health care policy development.

Beclin-1 has a central role in the regulation of autophagy. Barrett's esophagus (BE) is associated with a significantly increased risk for the development of esophageal adenocarcinoma (EAC). In the current study, we evaluated the role of Beclin-1 and autophagy in the EAC. Biopsies obtained from patients with BE and EAC, tissues from a rat model of BE and EAC, and esophageal cell lines were evaluated for the expression of Beclin-1 by immunohistochemistry, immunoblotting, or RT-PCR. Since reflux of bile acids is important in EAC, we also evaluated the effect of exposure to deoxycholic acid (DCA) on autophagy and Beclin-1 expression. Beclin-1 expression was high in squamous epithelium and nondysplastic BE, whereas its expression was low in dysplastic BE and EAC. The same pattern of expression was observed in rat tissues and in esophageal cell lines. Normal esophageal epithelium and HET-1A cells (derived from normal squamous epithelium) show high levels of Beclin-1, but lower levels of Beclin-1 were found in BE and EAC cell lines (CP-A, CP-C, and OE33). Acute exposure to DCA led to increased Beclin-1 expression and increased autophagy as evaluated by electron microscopy and counting percentage of GFP-LC3-positive BE cells with punctate pattern. In contrast, chronic exposure to DCA did not result in the alteration of Beclin-1 levels or autophagy. In summary, these data suggest that autophagy is initially activated in response to bile acids, but chronic exposure to bile acids leads to decreased Beclin-1 expression and autophagy resistance.

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