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The debate on tobacco taxes and fat taxes often treats smoking and eating as independent behaviors. However, since there exists medical and sociological evidence about the interdependence between eating and smoking choices, antismoking policies may also affect the obesity prevalence and fat taxes could influence smoking behavior. We address this issue from a theoretical standpoint and propose a dynamic rational model where eating and smoking are simultaneous choices that jointly affect body weight and addiction to smoking. Focusing on direct and cross price effects, we compare tobacco taxes and fat taxes and we show that a single policy tool can reduce both smoking and body weight. In particular, fat taxes can be more effective than tobacco taxes at simultaneously fighting obesity and smoking.

Policy interventions aimed at affecting a specific behavior may also indirectly affect individual choices in other domains. In this paper we study the direct effect of tobacco excise taxes and smoking bans on smoking behavior, and the indirect effect on eating behavior and body weight. Using very detailed clinical data on individual health, smoking, and dietary habits, we show that antismoking policies are effective in reducing smoking, but their consequences on eating behavior dramatically depend on the specific implemented policy. Increasing excise taxes on tobacco decreases body weight and caloric intake, and it improves the quality of eaten food. Smoking bans, instead, do not significantly affect body weight, although they impact on the diet composition. Smoking bans in restaurants induce a significant rise in the quality of food and in daily caloric intake. Conversely, smoking bans in bars negatively affect the quality of the daily diet, as individuals eat more fats and less fibers, and drink more alcohol and caffeine.

Our research activities target the use of biological methods for the evaluation of environmental quality, with particular reference to saltwater/brackish water and sediment. The choice of biological indicators must be based on reliable scientific knowledge and, possibly, on the availability of standardized procedures. In this article, we present a standardized protocol that used the marine crustacean Artemia to evaluate the toxicity of chemicals and/or of marine environmental matrices. Scientists propose that the brine shrimp (Artemia) is a suitable candidate for the development of a standard bioassay for worldwide utilization. A number of papers have been published on the toxic effects of various chemicals and toxicants on brine shrimp (Artemia). The major advantage of this crustacean for toxicity studies is the overall availability of the dry cysts; these can be immediately used in testing and difficult cultivation is not demanded1,2. Cyst-based toxicity assays are cheap, continuously available, simple and reliable and are thus an important answer to routine needs of toxicity screening, for industrial monitoring requirements or for regulatory purposes3. The proposed method involves the mortality as an endpoint. The numbers of survivors were counted and percentage of deaths were calculated. Larvae were considered dead if they did not exhibit any internal or external movement during several seconds of observation4. This procedure was standardized testing a reference substance (Sodium Dodecyl Sulfate); some results are reported in this work. This article accompanies a video that describes the performance of procedural toxicity testing, showing all the steps related to the protocol.

Our research activities target the use of biological methods for the evaluation of environmental quality, with particular reference to saltwater/brackish water and sediment. The choice of biological indicators must be based on reliable scientific knowledge and, possibly, on the availability of standardized procedures. In this article, we present a standardized protocol that used the marine crustacean Artemia to evaluate the toxicity of chemicals and/or of marine environmental matrices. Scientists propose that the brine shrimp (Artemia) is a suitable candidate for the development of a standard bioassay for worldwide utilization. A number of papers have been published on the toxic effects of various chemicals and toxicants on brine shrimp (Artemia). The major advantage of this crustacean for toxicity studies is the overall availability of the dry cysts; these can be immediately used in testing and difficult cultivation is not demanded1,2. Cyst-based toxicity assays are cheap, continuously available, simple and reliable and are thus an important answer to routine needs of toxicity screening, for industrial monitoring requirements or for regulatory purposes3. The proposed method involves the mortality as an endpoint. The numbers of survivors were counted and percentage of deaths were calculated. Larvae were considered dead if they did not exhibit any internal or external movement during several seconds of observation4. This procedure was standardized testing a reference substance (Sodium Dodecyl Sulfate); some results are reported in this work. This article accompanies a video that describes the performance of procedural toxicity testing, showing all the steps related to the protocol.

Asymmetries in cross-price elasticities have been demonstrated by several empirical studies. In this paper we study from a theoretical stance how introducing asymmetry in the substitution effects influences the sustainability of collusion. We characterize the equilibrium of a linear Cournot duopoly with substitute goods, and consider substitution effects which are asymmetric in magnitude. Within this framework, we study partial collusion using Friedman (1971) solution concept. Our main result shows that the interval of quantities supporting collusion in the asymmetric setting is always smaller than the interval in the symmetric benchmark. Thus, the asymmetry in the substitution effects makes collusion more difficult to sustain. This implies that previous Antitrust decisions could be reversed by considering the role of this kind of asymmetry.

Diethylene glycol (DEG) is commonly used to dehydrate natural gas in off-shore extraction plants and to prevent formation of gas hydrates. It may be released into the sea accidentally or in discharged produced waters (PWs). PWs samples from off-shore gas platforms in the Adriatic Sea (Italy) have been used in this study. The objectives of the study were: a) to evaluate the toxicity of DEG for marine organisms; b) to evaluate if a high DEG content in PWs may alter their toxicity; c) to verify whether the DEG threshold concentration established by the Italian legislation (3.5 g/l) for PWs discharged at sea is safe for marine environment. Ten different species (Vibrio fischeri, Phaeodactylum tricornutum, Dunaliella tertiolecta, Brachionus plicatilis, Artemia franciscana, Tigropus fulvus, Mytilus galloprovincialis, Crassostrea gigas, Tapes philippinarum and Dicentrarchus labrax) have been exposed to DEG; four of these species were also exposed to PWs in combination with DEG. The results showed that: a) DEG is not toxic at levels normally detected in Adriatic PWs; b) DEG in combination with PW showed mainly additive or synergistic effects; c) short-term bioassays showed that the DEG limit of 3.5 g/l could be acceptable.

Results Male-to-female ratio was 1 to 1. Median age at onset: 35,8 months (2-101 months); children < 6 months: 23%. Complete KD: 73%. Age was not significant different between complete and incomplete KD. Season of Onset of disease : winter in 35%, spring 31%, summer 11%, autumn 23%. Diagnostic signs: iperemic conjunctivitis and mucositis in 92% of pts, cutaneous rash in 88%, linfoadenopathy in 54%, alterations of extremities in 50%, desquamation of extremities in 58%; adjunctive signs: perineal dermatitis in 30% and diarrhea in 42%. 7 pts (5 boys) developed coronary involvement (group1): markers of inflammation and age at onset were not significantly different between group 1 and group 2 (without cardiac abnormalities). 28% of pts in group 1 was responder to therapy versus 47% in group 2. Coronary involvement regressed in all but 2 pts (both received late treatment).

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In this paper we study a duopoly where the network e¤ect is nonmonotone and the network can be overloaded. The firms choose prices and locations endogenously, and the agent's utility is influenced by the number of people patronizing the same firm she does. We determine the market equilibrium, and we study how the network effect influences social welfare. We compare this setting with the standard horizontal differentiation model with no network effects to understand whether and how conformism is socially desirable. The results show that whether network effects are desirable depends on how people are conformist, and whether overloading is feasible. If overloading is not possible (in either of the firm's network), and the total consumers' mass is sufficiently high, a network effect which is slightly concave increases social welfare. By contrast, if overloading is feasible, and the total consumers' mass is sufficiently small, social welfare is increased if the network effect is more concave than in the previous case.

The increasing concern of the policy maker about eating behavior has focused on the spread of obesity and on the evidence of a consistent number of individuals dieting despite being underweight. As the latter behavior is often attributed to the social pressure to be thin, some governments have already taken actions to ban ultra-thin ideals and testimonials. Assuming that people are heterogeneous in their healthy weights, but are exposed to the same ideal body weight, this paper proposes a theoretical framework to assess whether increasing the ideal body weight is socially desirable, both from a welfare and from a health point of view. If being overweight is the average condition and the ideal body weight is thin, increasing the ideal body weight may increase welfare by reducing social pressure. By contrast, health is on average reduced, since people depart even further from their healthy weight. Given that in the US and in Europe people are on average overweight, we conclude that these policies, even when are welfare improving, may foster the obesity epidemic.

In this paper we study a duopoly where the network e¤ect is nonmonotone and the network can be overloaded. The firms choose prices and locations endogenously, and the agent's utility is influenced by the number of people patronizing the same firm she does. We determine the market equilibrium, and we study how the network effect influences social welfare. We compare this setting with the standard horizontal differentiation model with no network effects to understand whether and how conformism is socially desirable. The results show that whether network effects are desirable depends on how people are conformist, and whether overloading is feasible. If overloading is not possible (in either of the firm's network), and the total consumers' mass is sufficiently high, a network effect which is slightly concave increases social welfare. By contrast, if overloading is feasible, and the total consumers' mass is sufficiently small, social welfare is increased if the network effect is more concave than in the previous case.

This review critically discusses the theoretical models of discounting through a selection of papers. It will focus on the comparison between the two major models, namely discounted utility and hyperbolic discounting. This paper differs from previous surveys in the attention given to the interpretation of models and suggestions for future research. First, it stresses how the economics literature is biased itself, since it considers only present-biased preferences on the basis of not well grounded evidence, while also future-biased preferences are worthwhile of attention to address relevant issues, like compulsive behaviors and work-life unbalance. Second, it makes qualifications on the meaning of self-awareness, distinguishing between cognitive boundaries and beliefs. Third, it suggests future direction of research to address this issue, fundamental for a sound policy analysis, by showing how the two main welfare criteria used in the literature to evaluate welfare of inconsistent individuals (long-run utility and Pareto criterion) have relevant shortcomings. Finally, it proposes a new perspective on misprediction of utility based on time perception

Gas turbine uptakes in some FFG-7 class ships have undergone cracking, a consequence of cyclic thermal stresses that occur during startup and powered operation. Because of this cracking, mainly in duct walls and some stiffeners, NavSea redesigned the FFG-7 class uptake, and ship designers have improved designs for new ship classes such as DDG-51 and MCM-1. These new designs employ insulation schemes and other features to reduce the thermal stresses associated with a gas turbine startup transient. This paper discusses the finite element methodology and thermal transient stress results of analyses on the redesigned FFG-7 class uptake, and the DDG-51 class and MCM-1 class gas turbine uptakes. It briefly describes the applicable ASME Code criteria and follows this discussion with a fatigue life evaluation with regard to crack initiation. Some design features that would mitigate thermal transient stresses due to startup, such as placement of insulation, stiffeners, and thicknesses are presented. A description is given of the dynamic shock analysis methodology used for shock qualification, and the application of computational fracture mechanics to predict the remaining life of the uptake at a location with an initial crack.

Objective To determine if mothers of youth with functional abdominal pain (FAP) experience more anxiety, depressive, and somatic symptoms and disorders than mothers of unaffected children. Design Case-control study. Setting Four primary care pediatric practices in western Pennsylvania. Participants Mothers of 8- to 15-year-old children and adolescents presenting with FAP (59 cases) or for routine care in the absence of recurrent pain (76 controls). Outcome Measures Questionnaires and blinded interviews assessing anxiety, depressive, and somatic symptoms and disorders; quality of life; and service use. Results On univariate analyses, mothers of FAP cases were significantly more likely than mothers of controls to have a lifetime history of irritable bowel syndrome (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.5-10.3), migraine (OR, 2.4; 95% CI, 1.1-5.3), and anxiety (OR, 4.8; 95% CI, 2.2-10.6), depressive (OR, 4.9; 95% CI, 2.2-11.0), and somatoform (OR, 16.1; 95% CI, 2.0-129.8) disorders than mothers of controls, and current anxiety, depressive, and somatic symptoms, poorer overall quality of life, and greater use of ambulatory health, but not mental health, services. Multivariate logistic regression found pediatric FAP to be most closely associated with maternal history of anxiety and depression (adjusted OR, 6.1; 95% CI, 1.8-20.8). Conclusions Functional abdominal pain may be better conceptualized as a disorder of emotion than a narrowly defined disorder of gastrointestinal function. Low rates of mental health service use by mothers of youth with FAP suggest that family health and illness attitudes deserve study.