22 research outputs found

    Evaluation of hazardous airborne carbonyls in five urban roadside dwellings: A comprehensive indoor air assessment in Sri Lanka

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    Indoor hazardous airborne carbonyls were quantified in five natural-ventilated roadside dwellings in Colombo, Sri Lanka. The total concentrations of all targeted carbonyls ranged from 13.6 to 18.6 mu g/m(3). Formaldehyde (C1) was the most abundant carbonyl, followed by acetaldehyde (C2) and acetone (C3K). The concentrations of C1 and C2 ranged from 3.3 to 8.5 mu g/m(3) and 2.3 to 4.4 mu g/m(3), respectively, which accounted for 23 to 42% and 18 to 26% respectively, to the total quantified carbonyls. The highest carbonyls levels were obtained in the dwelling located in an urban district with a mixture of industrial, commercial and residential areas. Much lower concentrations of carbonyls were measured in a light local traffic value was counted. Moderate correlations between individual combustion markers from vehicular emissions suggest the strong impacts from traffics to the indoor airs. The concentrations of C1 and C2 were compared with international indoor guidelines established by different authorities. A health assessment was conducted by estimation of inhalation cancer risk, implementing the inhalation unit risk values provided by Integrated Risk Information System (IRIS), associated with C1 and C2, which were 6.2 x 10(-5) and 7.7 x 10(-6), respectively. Even though the risks did not reach the action level (1 x 10(-4)), their health impact should not be overlooked. This kick-off indoor monitoring study provides valuable scientific data to the environmental science community since only limit data is available in Sri Lanka

    Price expectations and optimal sales promotion policies

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    The process of how people\u27s beliefs or expectations affect their behavior have been widely studied in the economic literature. Recently, the importance of price expectations in customers\u27 purchase decisions has received increasing attention in marketing. In this dissertation, we address various issues related to price expectations, such as: how are price expectations formed? How do price expectations affect customers\u27 purchase decisions? And, what are the effects of customers\u27 price expectations on a firm\u27s pricing and sales promotion strategies? Our work on price expectations is being carried out in two studies. The first study is an empirical analysis of scanner-panel data wherein, we use a two-stage modeling procedure to study customers\u27 price expectations. The first stage concerns the determination of brands\u27 expected prices. In the second stage, brand choice is assumed to depend on a brand\u27s retail price and the deviations of the brand\u27s retail price from its expected price. The results reveal that the proposed price expectations model of brand choice provides a significantly better fit than a traditional pricing model. We also find that a brand\u27s expected price is not only dependent on its past retail prices but, is also affected by the frequency with which the brand is promoted, economic conditions, customer characteristic and the type of store shopped. The second study uses an interactive computer-controlled experiment to obtain direct measures of the brand\u27s expected prices and the uncertainties associated with them. This study aims to: (i) investigate the dynamic effects of sales promotions on brands\u27 expected prices and the uncertainties associated with these expected prices, and (ii) hypothesize and test a price expectations model of the brand choice process. The effect of transaction utility on customers\u27 brand choices is found to be significant and this effect may depend on the frequency with which a brand is promoted. The nonlinear impact of sales promotions on customers\u27 price expectations found in this study also provides insights into the selection of optimal sales promotion schedules. Finally, we employ the results reported in the experimental study regarding the impact of sales promotions on customers\u27 price expectations and brand choice to evaluate through a simulation study the effectiveness of alternate sales promotion schedules under different cost conditions, competitive considerations, and different assumptions about the distributions of customers\u27 brand preferences

    Engaging customer cocreation in new product development through foreign subsidiaries : influences of multinational corporationsā€™ global integration and local adaptation mechanisms

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    Efforts to engage customers in cocreating new products have garnered much research attention from studies documenting customer cocreationā€™s (CCā€™s) positive impact on firm innovation and performance. Less research, however, has counterbalanced the bright side with the potential dark side of CC, especially as a strategy for multinational corporations (MNCs) operating in foreign markets. This study examines how MNC subsidiariesā€™ CC affects new product innovativeness and knowledge leakage to competitors. Adopting a broader agency perspective to recognize that subsidiaries often do not perform up to headquartersā€™ expectations due to both self-serving opportunism and honest incompetence, this study explores how CC effects are contingent on MNCsā€™ global management mechanisms. Using a dyadic managerial survey of 238 MNC subsidiaries, the authors find that MNCs can control knowledge leakage by implementing proper global integration and local adaptation mechanisms. However, CC may not improve new product innovativeness, except when the subsidiary has low local research-and-development staff influence. This study contributes to the CC literature by showing its benefits, challenges, and boundary conditions as a growing MNC innovation strategy

    A High-Tech Product Market Share Model with Customer Expectations

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    In a product category based on dynamic technology, new products enter the market in rapid succession, and the competitive situation changes almost daily. Because technological features of available products tend to improve while prices tend to decline, customers develop expectations that may influence their purchase decisions. We model the impact of customer expectations regarding and on product market share in the personal computer industry, finding significant nonlinear effects of both. These effects are observed when actual product price and/or technology differ from expectations by a threshold amount. Our results suggest implementable implications for high-tech product managers: in particular, price and technology should meet, but not exceed, customer expectations. This does not mean that managers should strive for mediocrity; rather, continuous improvement should be implemented so that product development efforts lead customer expectations.competitive strategy, pricing research, product policy

    Air pollution exacerbates mild obstructive sleep apnea by disrupting nocturnal changes in lower-limb body composition: a cross-sectional study conducted in urban northern Taiwan

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    Background: Few studies have explored the role of body composition linking air pollution to obstructive sleep apnea (OSA). Objective: To estimate the effects of air pollution on body composition and OSA, and that of body composition on OSA. Methods: This study included 3550 individuals. A spatiotemporal model estimated personal exposure. Nocturnal changes in body composition were assessed through bioelectric impedance analysis. OSA was diagnosed using polysomnography. A generalized linear model was used to evaluate the absolute nocturnal changes in body composition associated with an interquartile range (IQR) increase in pollutants. A generalized logistic model was used to estimate odds ratios (ORs) of mild-OSA compared to non-OSA. Association between body composition and apneaā€“hypopnea index (AHI) was investigated through partial least squares (PLS) regression. Results: Nocturnal changes in lower-limb body composition were associated with NO2 and PM2.5 in all patients. In participants with AHI <15, both short- and long-term NO2 exposures affected body composition and mild-OSA, while PM2.5 was not associated with either outcome. In a PLS model incorporating eight NO2-associated lower-limb parameters, the variable importance projection scores (VIP) of left leg impedance (LLIMP), predicted muscle mass (LLPMM), fat-free mass (LLFFM), and right leg impedance (RLIMP) exceeded 1; the corresponding coefficients ranked in the top four for AHI prediction. The adjusted OR (mild vs. non-OSA) was 1.67 (95 % CI: 1.36ā€“2.03) associated with an IQR increase in prediction value estimated from body compositions. Notably, the two-pollutant model investigating the effects of pollutants on body compositions revealed associations of four parameters (LLIMP, LLPMM, LLFFM, and RLIMP) with NO2 in all lags, which indicates their indispensability in the association between NO2 and AHI. Conclusions: NO2 exacerbates mild-OSA by disrupting nocturnal changes in lower-limb body composition of patients with AHI <15. PM2.5 was associated with nocturnal changes in lower-limb body composition but not with mild-OSA.This study was supported by the Vice-Chancellors Discretionary Fund of The Chinese University of Hong Kong (project no.: 4930744)

    Correction: Wai, M.G.C., et al. A Review of Pinealectomy-Induced Melatonin-Deficient Animal Models for the Study of Etiopathogenesis of Adolescent Idiopathic Scoliosis. Int. J. Mol. Sci. 2014, 15, 16484ā€“16499

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    The authors wish to make the following corrections to this paper [1]: The first name and surname of the authors were reversed. It should be corrected in the following format (with the surname in bold text):[...

    Indoor, outdoor, and personal exposure to PM2.5 and their bioreactivity among healthy residents of Hong Kong

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    Direct evidence about associations between fine particles (PM2.5) components and the corresponding PM2.5 bioreactivity at the individual level is limited. We conducted a panel study with repeated personal measurements involving 56 healthy residents in Hong Kong. Fractional exhaled nitric oxide (FeNO) levels were measured from these subjects. Out of 56 subjects, 27 (48.2%) participated in concurrent outdoor, indoor, and personal PM2.5 monitoring. Organic carbon (OC), elemental carbon (EC), particle bound-polycyclic aromatic hydrocarbons (PAHs), and phthalates were analyzed. Alteration in cell viability, lactic dehydrogenase (LDH), interleukin-6 (IL-6), and 8-isoprostane by 50 mu g/mL PM2.5 extracts was determined in A549 cells in vitro. Moderate heterogeneities were shown in PM2.5 exposures and the corresponding PM2.5 bioreactivity across different sample types. Associations between the analyzed components and PM2.5 bioreactivity were assessed using the multiple regression models. Toxicological results revealed that indoor and personal exposure to OC as well as PAH compounds and their derivatives (e.g., Alkyl-PAHs, Oxy-PAHs) induced cell viability reduction and increase in levels of LDH, IL-6, and 8-isoprostane. Overall, OC in personal exposure played a dominant role in PM2.5-induced bioreactivity. Subsequently, we examined the associations of FeNO with IL-6 and 8-isoprostane levels using mixed-effects models. The results showed that per interquartile change in IL-6 and 8-isoprostane were associated with a 6.4% (p < 0.01) and 11.1% (p < 0.01) increase in FeNO levels, respectively. Our study explored the toxicological properties of chemical components in PM2.5 exposure, which suggested that residential indoors and personal OC and PAHs should be of great concern for human health. These findings indicated that further studies in inflammation and oxidative stress-related illnesses due to particle exposure would benefit from the assessment of in vitro PM2.5 bioreactivity
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