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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jeem.2007.12.005 Byline: Jeremy Clark (a), Lana Friesen (b) Keywords: Order effects; Exclusive list; Warm glow; Contingent valuation Abstract: Contingent valuation researchers have found that the hypothetical values respondents place on a nested sequence of environmental goods are sensitive to the order in which the goods are presented. Typically, the smallest bundle of goods is valued more highly if presented first than if following more comprehensive bundles. Such effects appear even when each bundle is valued from an 'exclusive' list, or as an alternative to any other, so that income and substitution effects are controlled. We conduct lab experiments where participants are asked to value sequences of nested goods for purchase from an exclusive list using an incentive-compatible Becker-DeGroot-Marschak mechanism. We test whether order effects occur in valuation for (a) induced value goods, (b) actual private goods, and (c) identical private goods that are to be donated to charities. We find significant order effects when the goods are valued for own use, but not when they are valued for donation. Author Affiliation: (a) Department of Economics, University of Canterbury, Private Bag 4800, Christchurch, New Zealand (b) School of Economics, University of Queensland, Brisbane, Qld 4072, Australia Article History: Received 23 January 2006

The authors find that contributions to green energy programs are motivated both by program goals and by political attitudes.

A model was generated to assess the theory that individuals with altruistic tendencies will not manage as well as individuals with self-serving behavior in dealing with optimization problems. Traditional thinking attributes the former group's poor performance to their reliance on sub-optimal heuristics. However, results revealed that subjects who favored altruism fared as well, and even better, than groups with self-interested behaviour.

Purpose: To describe the eyelid condition known as "floppy eyelid syndrome" and to present the results of our experience treating patients with floppy eyelid syndrome.Methods: A retrospective analysis of 16 patients from 2009 to 2013 who underwent combined medial canthopexy and lateral tarsal strip by two surgeons (HBL and WRN) for the treatment of floppy eyelid syndrome (FES). Age, gender, presence of obstructive sleep apnea (OSA), papillary conjunctivitis, punctate keratopathy and lash ptosis were recorded pre-operatively. Outcomes assessed included improvement in upper eyelid laxity, operative complications, post-operative symptomatic relief and delayed recurrence of FES.Results: A total of 18 procedures (on 36 eyelids) were performed on 16 patients over the 4-year period. All patients (18/18) had relief of symptoms and good functional results, defined as improvement in lid laxity and resolution of symptoms. Average follow up was 124days. 8 of 16 patients (50%) had a pre-existing diagnosis of OSA. The remaining 8 patients were referred for sleep study and 2 were subsequently diagnosed with OSA. Two patients experienced some degree of FES recurrence without return of symptoms. There was one complication reported in which a partial dehiscence of the lateral canthal tendon occurred which did not require operative revision.Conclusions: Combined medial canthopexy and lateral tarsal strip are a safe and effective technique for the treatment of floppy eyelid syndrome. There is a strong association of FES and OSA and it is important to have any patient diagnosed with FES evaluated for OSA. [ABSTRACT FROM AUTHOR]

Environmental stimuli guide value-based decision making, but can do so through cognitive representation of outcomes or through general-incentive properties attributed to the cues themselves. We assert that these differences are conferred through the use of alternative associative structures differing in computational intensity. Using this framework, we review scientific evidence to discern the neural substrates of these assumed separable processes. We suggest that the contribution of the mesolimbic dopamine system to Pavlovian valuation is restricted to an affective system that is only updated through experiential feedback of stimulus–outcome pairing, whereas the orbitofrontal cortex contributes to an alternative system capable of inferential reasoning. Finally we discuss the interactions and convergence of these systems and their implications for decision making and its pathology. [Copyright &y& Elsevier]

Abstract: Compound 1 was identified as a HCV replication inhibitor from screening/early SAR triage. Potency improvement was achieved via modulation of substituent on the 5-azo linkage. Due to potential toxicological concern, the 5-azo linkage was replaced with 5-alkenyl or 5-alkynyl moiety. Analogs containing the 5-alkynyl linkage were found to be potent inhibitors of HCV replication. Further evaluation identified compounds 53 and 63 with good overall profile, in terms of replicon potency, selectivity and in vivo characteristics. Initial target engagement studies suggest that these novel carbanucleoside-like derivatives may inhibit the HCV replication complex (replicase). [Copyright &y& Elsevier]

Abstract: Methane emissions, concentrations, and oxidation were measured on eleven MSW landfills in eleven states spanning from California to Pennsylvania during the three year study. The flux measurements were performed using a static chamber technique. Initial concentration samples were collected immediately after placement of the flux chamber. Oxidation of the emitted methane was evaluated using stable isotope techniques. When reporting overall surface emissions and percent oxidation for a landfill cover, central tendencies are typically used to report “averages” of the collected data. The objective of this study was to determine the best way to determine and report central tendencies. Results showed that 89% of the data sets of collected surface flux have lognormal distributions, 83% of the surface concentration data sets are also lognormal. Sixty seven percent (67%) of the isotope measured percent oxidation data sets are normally distributed. The distribution of data for all eleven landfills provides insight of the central tendencies of emissions, concentrations, and percent oxidation. When reporting the “average” measurement for both flux and concentration data collected at the surface of a landfill, statistical analyses provided insight supporting the use of the geometric mean. But the arithmetic mean can accurately represent the percent oxidation, as measured with the stable isotope technique. We examined correlations between surface CH4 emissions and surface air CH4 concentrations. Correlation of the concentration and flux values using the geometric mean proved to be a good fit (R 2 =0.86), indicating that surface scans are a good way of identifying locations of high emissions. [Copyright &y& Elsevier]

We study a quantum dynamical semigroup driven by a Lindblad generator with a deterministic Schrödinger part and a noisy Poisson-timed scattering part. The dynamics describes the evolution of a test particle in ℝ n , n = 1, 2, 3, immersed in a gas, and the noisy scattering part is defined by the reduced effect of an individual interaction, where the interaction between the test particle and a single gas particle is via a repulsive point potential. In the limit that the mass ratio λ = m/M tends to zero and the collisions become more frequent as 1/λ, we show that our dynamics Φ tλ ◊ approaches a limiting dynamics Φ t,λ with second order error. Working in the Heisenberg representation, for G ∈ B(L2(ℝ n )) n = 1, 3 we bound the difference between Φ t,λ(G) and Φ t,λ ◊(G) in operator norm proportional to λ2. [Copyright &y& Elsevier]

Abstract: A series of purine nucleosides containing the 2′-deoxy-2′-fluoro-2′-C-methylribofuranosyl moiety were synthesized and evaluated as potential inhibitors of the hepatitis C virus in vitro. Of the nucleosides that were synthesized, only those possessing a 2-amino group on the purine base reduced the levels of HCV RNA in a subgenomic replicon assay. [Copyright &y& Elsevier]

Abstract: A history of sodium depletions has been found to potentiate the psychomotor as well as the rewarding effects of amphetamine, an indirect dopamine agonist. The present experiments were conducted to further define the role of dopamine receptor subtypes in this cross-sensitization effect. Rats with a history of sodium depletions were found to display psychomotor sensitization to a D2 but not a D1 direct agonist. Cross-sensitization between salt appetite and amphetamine was found to be blocked by a D2 but not a D1 antagonist. Together, these results implicate D2 but not D1 receptor function in the cross-sensitization seen after sodium depletions. [Copyright &y& Elsevier]

klotho is an aging suppressor gene and extends life span when overexpressed in mice. Klotho protein was recently demonstrated to function as a hormone that inhibits insulin/insulin-like growth factor-1 (IGF-1) signaling. Here we show that Klotho protein increases resistance to oxidative stress at the cellular and organismal level in mammals. Klotho protein activates the FoxO forkhead transcription factors that are negatively regulated by insulin/IGF-I signaling, thereby inducing expression of manganese superoxide dismutase. This in turn facilitates removal of reactive oxygen species and confers oxidative stress resistance. Thus, Klotho-induced inhibition of insulin/IGF-1 signaling is associated with increased resistance to oxidative stress, which potentially contributes to the anti-aging properties of klotho. [ABSTRACT FROM AUTHOR]

Published literature is investigated regarding the response of plants to various substances to determine the sensitivity of agricultural plants versus other species, the similarity of effects seen at different taxonomic levels, sensitivity of plants growing outdoors versus in a greenhouse, and the sensitivity of different measurement endpoints. We find that agricultural species are not consistently more or less sensitive to the herbicides tested than non-crop species. Genus and family taxonomic groupings may show similar responses among species, but this similarity quickly decreases as the comparison progress between orders and classes. Results from field and greenhouse studies are less in agreement between studies than data from the other topics. Shoot length will be affected at concentrations lower than for other vegetative endpoints for most species tested for inorganic substances, but for organic substances root and shoot mass were more sensitive. Overall, there is no one species or endpoint that is consistently the most sensitive for all species or all chemicals in all soils, and differences in bioavailability among compounds may confound comparison of test results. Therefore, species sensitivity distributions, adjusted for bioavailability when possible, should be considered in order to better evaluate effects to non-target terrestrial plants. [Copyright &y& Elsevier]

Previous work in our laboratory has demonstrated a potentiation of the psychomotor effects of amphetamine in animals with a history of sodium depletion, a process referred to as cross-sensitization. The present studies were done to further develop this finding by assessing multiple effects of amphetamine in rats with and without a history of sodium depletion. For Experiments 1–3, rats were depleted of sodium twice then subjected to one of three experimental procedures [open-field activity, conditioned place preference (CPP) and conditioned taste aversion (CTA)]. A history of depletion produced an elevation in the psychomotor effects of amphetamine. CPP, used to assess the rewarding properties of amphetamine, developed in rats with a history of depletion but not in controls. The aversive component of amphetamine as measured by CTA was unaffected by previous experience with sodium depletion. Finally, acute salt appetite after depletion was assessed in rats exposed to a sensitizing regimen of amphetamine. Animals with a drug history demonstrated a significant elevation in NaCl solution intake after depletion in comparison to controls. Together, the data provide strong evidence for the reciprocal cross-sensitization of salt appetite and response to amphetamine. [Copyright &y& Elsevier]

Abstract Background The hemostatic system cooperates with proteolytic degradation in processes allowing abdominal aortic aneurysm (AAA) formation. In previous studies, it has been suggested that aneurysm rupture depends on intraluminal thrombus (ILT) thickness, which varies across each individual aneurysm. We hypothesized that hemostatic components differentially accumulate in AAA tissue in relation to ILT thickness. Thick (A1) and thin (B1) segments of ILTs and aneurysm wall sections A (adjacent to A1) and B (adjacent to B1) from one aneurysm sac were taken from 35 patients undergoing elective repair. Methods Factor levels were measured using enzyme-linked immunosorbent assay of protein extract. Results Tissue factor (TF) activities were significantly higher in thinner segments of AAA (B1 vs A1, P =.003; B vs A, P <.001; B vs A1, P <.001; B vs B1, P =.001). Significantly higher tissue plasminogen activator was found in thick thrombus-covered wall segments (A) than in B, A1, and B1 (P =.015, P <.001, and P <.001, respectively). Plasminogen concentrations were highest in ILT. Concentrations of α 2 -antiplasmin in thin ILT adjacent walls (B) were higher compared with wall (A) adjacent to thick ILT (P =.021) and thick ILT (A1; P <.001). Significant correlations between levels of different factors were mostly found in thick ILT (A1). However, no correlations were found at B sites, except for a correlation between plasmin and TF activities (r = 0.55; P =.004). Conclusions These results suggest that higher TF activities are present in thinner AAA regions. These parameters and local fibrinolysis may be part of the processes leading to destruction of the aneurysm wall. Clinical Relevance Intraluminal thrombus (ILT) and abdominal aortic aneurysm wall thickness vary significantly across each individual aneurysm. The study suggests that intensified coagulation and probably local fibrinolysis in thin ILT segments may be part of a chain reaction leading to the destruction of the aneurysm wall and, as a result, its rupture. Considering the significant ability of coagulative and fibrinolytic systems to construct ILT as well as to regulate extracellular matrix proteolysis of the abdominal aortic aneurysm wall, the spatiotemporal distribution of components of these two systems represents data that may improve patient-specific models of aneurysmal progression and rupture risk in the future. [ABSTRACT FROM AUTHOR]

Gaining a better understanding of the biological mechanisms underlying the individual variation observed in response to rewards and reward cues could help to identify and treat individuals more prone to disorders of impulsive control, such as addiction. Variation in response to reward cues is captured in rats undergoing autoshaping experiments where the appearance of a lever precedes food delivery. Although no response is required for food to be delivered, some rats (goal-trackers) learn to approach and avidly engage the magazine until food delivery, whereas other rats (sign-trackers) come to approach and engage avidly the lever. The impulsive and often maladaptive characteristics of the latter response are reminiscent of addictive behaviour in humans. In a previous article, we developed a computational model accounting for a set of experimental data regarding sign-trackers and goal-trackers. Here we show new simulations of the model to draw experimental predictions that could help further validate or refute the model. In particular, we apply the model to new experimental protocols such as injecting flupentixol locally into the core of the nucleus accumbens rather than systemically, and lesioning of the core of the nucleus accumbens before or after conditioning. In addition, we discuss the possibility of removing the food magazine during the inter-trial interval. The predictions from this revised model will help us better understand the role of different brain regions in the behaviours expressed by sign-trackers and goal-trackers. [ABSTRACT FROM AUTHOR]

Summary: Background: Biomarkers are urgently needed to dissect the heterogeneity of prostate cancer between patients to improve treatment and accelerate drug development. We analysed blood mRNA expression arrays to identify patients with metastatic castration-resistant prostate cancer with poorer outcome. Methods: Whole blood was collected into PAXgene tubes from patients with castration-resistant prostate cancer and patients with prostate cancer selected for active surveillance. In stage I (derivation set), patients with castration-resistant prostate cancer were used as cases and patients under active surveillance were used as controls. These patients were recruited from The Royal Marsden Hospital NHS Foundation Trust (Sutton, UK) and The Beatson West of Scotland Cancer Centre (Glasgow, UK). In stage II (validation-set), patients with castration-resistant prostate cancer recruited from the Memorial Sloan-Kettering Cancer Center (New York, USA) were assessed. Whole-blood RNA was hybridised to Affymetrix U133plus2 microarrays. Expression profiles were analysed with Bayesian latent process decomposition (LPD) to identify RNA expression profiles associated with castration-resistant prostate cancer subgroups; these profiles were then confirmed by quantative reverse transcriptase (qRT) PCR studies and correlated with overall survival in both the test-set and validation-set. Findings: LPD analyses of the mRNA expression data divided the evaluable patients in stage I (n=94) into four groups. All patients in LPD1 (14 of 14) and most in LPD2 (17 of 18) had castration-resistant prostate cancer. Patients with castration-resistant prostate cancer and those under active surveillance comprised LPD3 (15 of 31 castration-resistant prostate cancer) and LDP4 (12 of 21 castration-resistant prostate cancer). Patients with castration-resistant prostate cancer in the LPD1 subgroup had features associated with worse prognosis and poorer overall survival than patients with castration-resistant prostate cancer in other LPD subgroups (LPD1 overall survival 10·7 months [95% CI 4·1–17·2] vs non-LPD1 25·6 months [18·0–33·4]; p<0·0001). A nine-gene signature verified by qRT-PCR classified patients into this LPD1 subgroup with a very low percentage of misclassification (1·2%). The ten patients who were initially unclassifiable by the LPD analyses were subclassified by this signature. We confirmed the prognostic utility of this nine-gene signature in the validation castration-resistant prostate cancer cohort, where LPD1 membership was also associated with worse overall survival (LPD1 9·2 months [95% CI 2·1–16·4] vs non-LPD1 21·6 months [7·5–35·6]; p=0·001), and remained an independent prognostic factor in multivariable analyses for both cohorts. Interpretation: Our results suggest that whole-blood gene profiling could identify gene-expression signatures that stratify patients with castration-resistant prostate cancer into distinct prognostic groups. Funding: AstraZeneca, Experimental Cancer Medicine Centre, Prostate Cancer Charity, Prostate Cancer Foundation. [Copyright &y& Elsevier]

Abstract: Introduction of nitrogen atom into the benzene ring of a previously identified HCV replication (replicase) benzofuran inhibitor 2, resulted in the discovery of the more potent pyridofuran analogue 5. Subsequent introduction of small alkyl and alkoxy ligands into the pyridine ring resulted in further improvements in replicon potency. Replacement of the 4-chloro moiety on the pyrimidine core with a methyl group, and concomitant monoalkylation of the C-2 amino moiety resulted in the identification of several inhibitors with desirable characteristics. Inhibitor 41, from the monosubstituted pyridofuran and inhibitor 50 from the disubstituted series displayed excellent potency, selectivity (GAPDH/MTS CC50) and PK parameters in all species studied, while the selectivity in the thymidine incorporation assay (DNA·CC50) was low. [Copyright &y& Elsevier]

Summary: Background: The E2F3 transcription factor has an established role in controlling cell cycle progression. In previous studies we have provided evidence that nuclear E2F3 overexpression represents a mechanism that drives the development of human bladder cancer and that determines aggressiveness in human prostate cancer. We have proposed a model in which E2F3 overexpression co-operates with removal of the E2F inhibitor pRB to facilitate cancer development. Since small cell lung cancers (SCLC) have one of the highest reported frequencies of functional abnormalities in the pRB protein (90%) of any human cancer, we wish to assess to what extent E2F3 would be overexpressed in this and other classes of human lung cancer. Methods: Immunohistochemical techniques were used to assess the E2F3 status in 428 samples of lung cancers, lung carcinoids, normal bronchial epithelium and normal lung tissue. Results: E2F3 is overexpressed in 55–70% of squamous cell carcinomas and 79% of adenocarcinomas of the lung. In addition very high level expression of nuclear E2F3 is found in almost all small cell lung cancers analysed. When considered together with published data our observations indicate that co-operation between pRB functional knockouts and E2F3 overexpression may represent a mechanism of development of SCLC. [Copyright &y& Elsevier]