Tumor cyclooxygenase-2 levels correlate with tumor invasiveness in human hepatocellular carcinoma

Aim: Recent studies suggested that cyclooxygenase-2 (COX-2) enhances tumor angiogenesis via upregulation of vascular endothelial growth factor (VEGF). Although COX-2 expression has been demonstrated in hepatocellular carcinoma (HCC), the significance of COX-2 in progression of HCC remains unclear. This study evaluated the clinicopathological correlation of COX-2 level and its relationship with VEGF level in HCC. Methods: Fresh tumor tissues were obtained from 100 patients who underwent resection of HCC. COX-2 protein expression was examined by immunohistochemistry, and quantitatively by an enzyme immunometric assay (EIA) of tumor cytosolic COX-2 levels. Tumor cytosolic VEGF levels were measured by an ELISA. Results: Immunostaining showed expression of COX-2 in tumor cells. Tumor cytosolic COX-2 levels correlated with VEGF levels (r = 0.469, P<0.001). Correlation with clinicopathological features showed significantly higher tumor cytosolic COX-2 levels in the presence of multiple tumors (P = 0.027), venous invasion (P = 0.030), microsatellite lesions (P = 0.037) and advanced tumor stage (P = 0.008). Higher tumor cytosolic COX-2 levels were associated with worse patient survival. Conclusion: This study shows that elevated tumor COX-2 levels correlate with elevated VEGF levels and invasiveness in HCC, suggesting that COX-2 plays a significant role in the progression of HCC. © 2005 The WJG Press and Elsevier Inc. All rights reserved.published_or_final_versio

A novel consistent random forest framework: Bernoulli random forests

© 2012 IEEE. Random forests (RFs) are recognized as one type of ensemble learning method and are effective for the most classification and regression tasks. Despite their impressive empirical performance, the theory of RFs has yet been fully proved. Several theoretically guaranteed RF variants have been presented, but their poor practical performance has been criticized. In this paper, a novel RF framework is proposed, named Bernoulli RFs (BRFs), with the aim of solving the RF dilemma between theoretical consistency and empirical performance. BRF uses two independent Bernoulli distributions to simplify the tree construction, in contrast to the RFs proposed by Breiman. The two Bernoulli distributions are separately used to control the splitting feature and splitting point selection processes of tree construction. Consequently, theoretical consistency is ensured in BRF, i.e., the convergence of learning performance to optimum will be guaranteed when infinite data are given. Importantly, our proposed BRF is consistent for both classification and regression. The best empirical performance is achieved by BRF when it is compared with state-of-the-art theoretical/consistent RFs. This advance in RF research toward closing the gap between theory and practice is verified by the theoretical and experimental studies in this paper

Product Development in Crowdfunding: Theoretical and Empirical Analysis

Crowdfunding goes beyond raising funds. Entrepreneurs often use crowdfunding to solicit feedback from customers to improve their products, and may therefore prefer to launch crowdfunding campaigns for a basic version of their products with few or no enhancements (i.e., limited features). Yet, customers may not be persuaded by a campaign if a product appears too basic. In view of this trade-off, a key question for an entrepreneur is how far a product should be enhanced before launching a crowdfunding campaign. Analyzing a game-theoretical model and testing its predictions empirically, we study how a product's level of enhancement at campaign launch influences both whether an entrepreneur continues to improve the product during the campaign and whether the campaign is successful. We show that as the product's level of enhancement at campaign launch increases, the likelihood of product improvement during a campaign at first increases (because customers are more likely to provide feedback) and then decreases (because of increased production cost for the entrepreneur). Furthermore, although our theoretical model intuitively predicts that the likelihood of campaign success will always increase when an entrepreneur launches a campaign for a more enhanced product, our empirical analysis shows that the likelihood of campaign success first increases and then decreases. This counterintuitive result may be due to customers being overwhelmed with the complexity of highly enhanced products. Finally, while crowdfunding experts believe that products should be enhanced as much as possible before a campaign, we show that this is not always the best strategy

The differential effects of intimate terrorism and situational couple violence on mental health outcomes among abused Chinese women: a mixed-method study

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Irradiation-induced molecular dipole reorientation in inverted polymer solar cell using small molecular electron collection layer

Inverted polymer solar cell is developed using small molecular tris(8-hydroxyquinolinato) aluminum (Alq3) as an electron collection layer between the active layer and indium-tin-oxide bottom cathode. Upon post-processing light irradiation by simulated solar illumination, the open-circuit voltage of the inverted device increases from 0.52 V to 0.60 V, resulting in the enhancement of the power conversion efficiency from 2.54 to 3.33 with negligible change in the short-circuit current. The performance improvement is attributed to the removal of surface potential due to irradiation-induced molecular dipole reorientation in the Alq3 layer, which reduces the charge transport barrier and improves the charge collection efficiency. © 2011 American Institute of Physics

Turbulent properties of internal waves in the South China Sea

Author Posting. © The Oceanography Society, 2011. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 24 no. 4 (2011): 78–87, doi:10.5670/oceanog.2011.96.Luzon Strait and South China Sea waters are among the most energetic internal wave environments in the global ocean. Strong tides and stratification in Luzon Strait give rise to internal waves that propagate west into the South China Sea. The energy carried by the waves is dissipated via turbulent processes. Here, we present and contrast the relatively few direct observations of turbulent dissipation in South China Sea internal waves. Frictional processes active in the bottom boundary layer dissipate some of the energy along China's continental shelf. It appears that more energy is lost in Taiwanese waters of the Dongsha Plateau, where the waves reach their maximum amplitudes, and where the bottom topography abruptly shoals from 3,000 m in the deep basin to 1,000 m and shallower on the plateau. There, energy dissipation by turbulence reaches 1 W m–2, on par with the conversion rates of Luzon Strait.Support for this work was provided by the US Office of Naval Research and the National Science Council of Taiwan

Who needs nature? The influence of employee speciesism on nature-based need satisfaction and subsequent work behavior

Scholars have long upheld the notion that exposure to nature benefits individuals. Recently, organizational researchers have theorized that these benefits extend to the workplace, leading to calls for organizations to incorporate contact with nature into employees’ jobs. However, it is unclear whether the effects of nature are strong enough to meaningfully impact employee performance, thereby justifying organizations’ investments in it. In this research, we draw on self-determination theory to develop a theoretical model predicting that exposure to nature at work satisfies employees’ psychological needs (i.e., needs for autonomy, relatedness, and competence), and positively affects their subsequent task performance and prosocial behavior. In addition, we theorize that the effects of nature on need satisfaction are weaker in employees higher on speciesism (i.e., the belief that humans are superior to other forms of life). We test these predictions with a mixed-method approach comprised of an online experiment in the United States (Study 1), a field experiment in Hong Kong (Study 2), a multi-wave, multi-source field study in Taiwan (Study 3), and a multi-wave, multi-source field study (with objective performance scores) in New Zealand (Study 4). Overall, our findings largely support our theoretical model

Intimate partner sexual aggression against Chinese women: a mixed methods study

Abstract Background: Although intimate partner sexual aggression has been shown to be associated with adverse mental health outcomes, there is scant information about sexual aggression in Chinese intimate relationships in general and about its mental health impact in particular. This article aimed to investigate sexual aggression in Chinese intimate relationships, including the use of force or threat of force and non-physical coercive tactics in unwanted sex. Methods: The quantitative and qualitative data used in this paper were drawn from a prospective cohort study conducted in Hong Kong between September 2010 and September 2012. A total of 745 Chinese women aged 18 or older who had been in an intimate relationship in the preceding 12 months were recruited from sites in all districts of Hong Kong. Multiple logistic regression analysis, ordinary linear regression, and t-tests were used in quantitative analysis. Directed content analysis was used to analyze the transcripts of 59 women who revealed experiences of intimate partner sexual aggression in individual in-depth interviews. Results: Of the 745 Chinese women in the study, 348 (46.7%) had experienced intimate partner physical violence in the past year, and 179 (24%) had experienced intimate partner physical violence and sexual aggression in the past year. Intimate partner sexual aggression significantly predicted PTSD and depressive symptoms after controlling for intimate partner physical violence. Among the 179 women reporting intimate partner physical violence and sexual coercion in the past year, 75 indicated that their partners used force or threat of force to make them have sex, and 104 of them reported that they gave in to sex because of non-physical coercive tactics used by their partners. Qualitative data revealed a variety of non-physical coercive tactics with different degrees of subtlety used to coerce women into unwanted sex with their partners. Chinese women experiencing physically forced sex had significantly more depressive symptoms and PTSD symptoms. Conclusions: Our findings indicate that sexual aggression in Chinese intimate relationships has specific mental health consequences over and above those associated with physical violence. Assessment of partner violence in Chinese relationships should include screening for sexual aggression in order to provide appropriate interventions. Trial registration: ClinicalTrials gov NCT01206192 Keywords: Intimate partner, Sexual aggression, Mental health, Women, Chinesepublished_or_final_versio