New Examples of Marginally Trapped Surfaces and Tubes in Warped Spacetimes

In the present paper we provide new examples of marginally trapped surfaces and tubes in FLRW spacetimes by using a basic relation between these objects and CMC surfaces in 3-manifolds. We also provide a new method to construct marginally trapped surfaces in closed FLRW spacetimes, which is based on the classical Hopf map. The utility of this method is illustrated by providing marginally trapped surfaces crossing expanding and collapsing regions of a closed FLRW spacetime. The approach introduced in this paper is also extended to twisted spaces.Comment: 20 page

Somatic symptom disorder in dermatology

Somatic symptom disorder (SSD) is defined by the prominence of somatic symptoms associated with abnormal thoughts, feelings, and behaviors related to the symptoms, resulting in significant distress and impairment. Individuals with these disorders are more commonly encountered in primary care and other medical settings, including dermatology practice, than in psychiatric and other mental health settings. What defines the thoughts, feelings, and behaviors as abnormal is that they are excessive, that is, out of proportion to other patients with similar somatic symptoms, and that they result in significant distress and impairment. SSD may occur with or without the presence of a diagnosable dermatologic disorder. When a dermatologic disorder is present, SSD should be considered when the patient is worrying too much about his or her skin, spending too much time and energy on it, and especially if the patient complains of many nondermatologic symptoms in addition. The differential diagnosis includes other psychiatric disorders, including depression, anxiety disorders, delusions of parasitosis, and body dysmorphic disorder

Consumer Preferences for U.S. Pork in Urban China

China’s transition into a developed economy is driving changes in consumer preferences and demand for foods. To evaluate consumer preferences for U.S. pork in urban China, primary data were collected in two metropolitan areas- Beijing and Shanghai. Estimated logit models revealed that an individual’s age, shopping location and food safety concerns significantly influenced their willingness-to-pay for U.S. pork. A proportional linear model was developed to evaluate factors affecting purchasing behavior of western-style pork cuts vs. traditional Chinese cuts. Food safety concerns were linked to a previous lean-meat additive scare and a lack of consumer confidence on the Chinese food inspection system.China, U.S. Pork, Willingness-to-pay, Ordered Logit, food safety, Agricultural and Food Policy, Consumer/Household Economics, Marketing, D120, D190, M390, Q130, Q180,

A Statistical Prescription to Estimate Properly Normalized Distributions of Different Particle Species

We describe a statistical method to avoid biased estimation of the content of different particle species. We consider the case when the particle identification information strongly depends on some kinematical variables, whose distributions are unknown and different for each particles species. We show that the proposed procedure provides properly normalized and completely data-driven estimation of the unknown distributions without any a priori assumption on their functional form. Moreover, we demonstrate that the method can be generalized to any kinematical distribution of the particles

BCS pairing in fully repulsive fermion mixtures

We consider a mixture of two neutral cold Fermi gases with repulsive interactions. We show that in some region of the parameter space of the system the effective attraction between fermions of the same type can appear due to the exchange of collective excitations. This leads to the formation of BCS pairing in the case where bare inter-atomic interactions are repulsive

Modeling Heterogeneity in Consumer Preferences for Select Food Safety Attributes in China

Food safety issues often arise from problems of asymmetric information between consumers and suppliers with regards to product-specific attributes. Severe food safety scandals were observed recently in China that not only caused direct economic and life loss but also created distrust in the Chinese food system domestically as well as internationally. While much attention has focused on the problems plaguing the Chinese government’s food inspection system, little research has been dedicated to analyze consumers’ concerns over food safety. In this paper we measure consumer preferences for select food safety attributes in pork and take their food safety risk perceptions into account. Several choice experiment models, including latent class and random parameters logit, are constructed to capture heterogeneity in consumer preferences. A statistical sample of 6,720 observations is obtained from a choice experiment administered in seven major Chinese metropolitan cities. Our results suggest that Chinese consumers have the highest willingness-to-pay for a government certification program, followed by a traceability system, third party certification and a product-specific information label. The results of this study call upon the direct involvement of the Chinese government in the food safety system. A more strict monitoring system will not only improve consumer welfare in the short-run but also restore consumers’ trust leading to a social welfare increase in the long run.Food safety, choice experiment, willingness-to-pay, risk perceptions, random parameters logit, latent class logit, Agricultural and Food Policy, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety, Q13, Q17, Q18,