Limiting transportation sector greenhouse gas emissions: the role of system interactions on policy portfolio effectiveness

Significant cuts in global greenhouse gas (GHGs) emissions have been called for by numerous experts and science organizations to avert the negative effects of climate change. Light duty vehicles (LDVs) will play an important role in any new reduction policy due to their daily use, citizen reliance, and significant consumption of fossil fuels. Unfortunately, a single policy aimed at LDVs and one that results in the necessary reductions in a politically acceptable manner may not be possible. Instead, a policy portfolio approach may be needed. Implementing multiple policy mechanisms via a policy portfolio may create system effects that either reduce or enhance the effectiveness of these policies. This thesis evaluates the interaction effects among three possible GHG reduction policies: a carbon tax, fuel economy standard, and vehicle subsidies. The thesis applies a systems dynamic model to explore these interaction effects both qualitatively and quantitatively. The results demonstrate how GHG reduction policies should or should not be used in combination in order to maximize their effectiveness

Transgenic amplification of glucocorticoid action in adipose tissue causes high blood pressure in mice

Obesity is closely associated with the metabolic syndrome, a combination of disorders including insulin resistance, diabetes, dyslipidemia, and hypertension. A role for local glucocorticoid reamplification in obesity and the metabolic syndrome has been suggested. The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) regenerates active cortisol from inactive 11-keto forms, and aP2-HSD1 mice with relative transgenic overexpression of this enzyme in fat cells develop visceral obesity with insulin resistance and dyslipidemia. Here we report that aP2-HSD1 mice also have high arterial blood pressure (BP). The mice have increased sensitivity to dietary salt and increased plasma levels of angiotensinogen, angiotensin II, and aldosterone. This hypertension is abolished by selective angiotensin II receptor AT-1 antagonist at a low dose that does not affect BP in non-Tg littermates. These findings suggest that activation of the circulating renin-angiotensin system (RAS) develops in aP2-HSD1 mice. The long-term hypertension is further reflected by an appreciable hypertrophy and hyperplasia of the distal tubule epithelium of the nephron, resembling salt-sensitive or angiotensin II–mediated hypertension. Taken together, our findings suggest that overexpression of 11β-HSD1 in fat is sufficient to cause salt-sensitive hypertension mediated by an activated RAS. The potential role of adipose 11β-HSD1 in mediating critical features of the metabolic syndrome extends beyond obesity and metabolic complications to include the most central cardiovascular feature of this disorder

The Decreasing Significance of Stigma in the Lives of Bisexual Men: Keynote Address, Bisexual Research Convention, London

This article is constructed around a keynote address given at the Bisexual Research Convention, held in London 2010. The keynote was delivered by sociologist Eric Anderson, on behalf of himself and the other authors of this article. The keynote reflected upon a body of ongoing research, funded by the American Institute of Bisexuality and collected by this team of researchers, into the changing relationship between men and homophobia. It first contextualizes 20th-century attitudes toward homo/bisexuality before showing a declining significance of biphobia and homophobia in men's lives today. In accordance with the keynote, this article draws from preliminary findings of multiple ongoing studies of bisexual men in the United States and the United Kingdom

Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo

Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201

The effects of testosterone exposure on urogenital tract androgen receptor distribution in immature eastern fence lizards

Androgens are important to the development and maintenance of reproductive structures and functions; however, less is known about the importance of androgen signaling in females compared to males. The distribution of androgen receptors (ARs) in mammalian urogenital systems has been characterized but relatively little is known about AR expression in non-mammalian vertebrates. In this study, AR was immunolocalized in the urogenital tracts of juvenile eastern fence lizards, Sceloporus undulatus. A subset of lizards received testosterone implants to understand and examine the effects of elevated testosterone (T) on AR expression. Our results showed control males had moderate AR-positive staining within the epididymal epithelium and diffuse staining throughout the testes, with minor staining surrounding the sexual segments of the kidney. Control females revealed a similar intensity of staining within their oviduct and mesonephric ducts. Elevated T in lizards that received implants led to hypertrophied reproductive tracts and increased AR expression throughout most of the urogenital system. As compared to control males, males that received exogenous T revealed darker AR staining in the testis, spermatic ducts, and the sexual segments of the kidney. Androgen receptor staining was more intense and concentrated in the nuclei of the epithelia of the oviducts and ductus deferentia of T-treated females in comparison to controls. Our results demonstrate that the urogenital tracts of both sexes are androgen sensitive, and the tissues that responded the most dramatically to elevated T were the same tissues that had the most intense AR staining. Our results also suggest that exposure to elevated T concentrations leads to upregulation of AR expression and increased nuclear translocation. Although oviducts of T-treated females exhibited hypertrophy relative to untreated females and were AR positive, it is unclear if this was through direct actions of testosterone or the aromatization of androgens to estrogens

Greenhouse gas mitigation policies and the transportation sector: The role of feedback effects on policy effectiveness

a b s t r a c t The US transportation sector is a major contributor to global greenhouse gas (GHG) emissions. As such, policymakers and stakeholder groups have proposed a number of policy instruments aimed at reducing these emissions. In order to fully evaluate the effectiveness of these policies, policymakers must consider both the direct responses associated with policy actions, and the indirect responses that occur through complex relationships within socioeconomic systems. In cases where multiple policy instruments are employed, these indirect effects create policy interactions that are either complementary or competing; policymakers need to understand these interactions in order to leverage policy synergies and manage policy conflicts. Analysis of these indirect effects is particularly difficult in the transportation sector, where system boundaries are uncertain and feedback among systems components can be complicated. This paper begins to address this problem by applying systems dynamics tools (in particular causal loop diagrams) to help identify and understand the role of feedback effects on transportation-related GHG reduction policies. Policymakers can use this framework to qualitatively explore the impacts of various policy instruments, as well as identify important relationships that can be later included in quantitative modeling approaches

Greenhouse gas mitigation policies and the transportation sector: The role of feedback effects on policy effectiveness

The US transportation sector is a major contributor to global greenhouse gas (GHG) emissions. As such, policymakers and stakeholder groups have proposed a number of policy instruments aimed at reducing these emissions. In order to fully evaluate the effectiveness of these policies, policymakers must consider both the direct responses associated with policy actions, and the indirect responses that occur through complex relationships within socioeconomic systems. In cases where multiple policy instruments are employed, these indirect effects create policy interactions that are either complementary or competing; policymakers need to understand these interactions in order to leverage policy synergies and manage policy conflicts. Analysis of these indirect effects is particularly difficult in the transportation sector, where system boundaries are uncertain and feedback among systems components can be complicated. This paper begins to address this problem by applying systems dynamics tools (in particular causal loop diagrams) to help identify and understand the role of feedback effects on transportation-related GHG reduction policies. Policymakers can use this framework to qualitatively explore the impacts of various policy instruments, as well as identify important relationships that can be later included in quantitative modeling approaches.Transportation policy Climate change Systems modeling

Whole body vibration elicits differential immune and metabolic responses in obese and normal weight individuals

Traditional aerobic exercise reduces the risk of developing chronic diseases by inducing immune, metabolic, and myokine responses. Following traditional exercise, both the magnitude and time-course of these beneficial responses are different between obese compared to normal weight individuals. Although obesity may affect the ability to engage in traditional exercise, whole body vibration (WBV) has emerged as a more tolerable form of exercise . The impact of WBV on immune, metabolic, and myokine responses as well as differences between normal weight and obese individuals, however, is unknown. Purpose: To determine if WBV elicits differential magnitudes and time-courses of immune, metabolic, and myokine responses between obese and normal weight individuals. Methods: 21 participants [Obese (OB): n = 11, Age: 33 ± 4 y, percent body fat (%BF): 39.1 ± 2.4% & Normal weight (NW) n = 10, Age: 28 ± 8 y, %BF: 17.4 ± 2.1%] engaged in 10 cycles of WBV exercise [1 cycle = 1 min of vibration followed by 30 s of rest]. Blood samples were collected pre-WBV (PRE), immediately (POST), 3 h (3H), and 24 h (24H) post-WBV and analyzed for leukocytes, insulin, glucose, and myokines (IL-6, decorin, myostatin). Results: The peak (3H) percent change in neutrophil counts (OB: 13.9 ± 17.4 vs. NW: 47.2 ± 6.2%Δ; p = 0.007) was different between groups. The percent change in neutrophil percentages was increased in NW (POST: -1.6 ± 2.0 vs. 3H: 13.0 ± 7.2%Δ, p = 0.019) but not OB (p > 0.05). HOMA β-cell function was increased at 24H (PRE: 83.4 ± 5.4 vs. 24H: 131.0 ± 14.1%; p = 0.013) in NW and was not altered in OB (p > 0.05). PRE IL-6 was greater in OB compared to NW (OB: 2.7 ± 0.6 vs. NW: 0.6 ± 0.1 pg/mL; p = 0.011); however, the percent change from PRE to peak (3H) was greater in NW (OB: 148.1 ± 47.9 vs. NW: 1277.9 ± 597.6 %Δ; p = 0.035). Creatine kinase, decorin, and myostatin were not significantly altered in either group (p > 0.05). Conclusion: Taken together, these data suggest that acute whole body vibration elicits favorable immune, metabolic, and myokine responses and that these responses differ between obese and normal weight individuals