RESUMEN
Peak heat flow occurs at mid-ocean ridges and decreases with the age of the oceanic lithosphere. Several plate models, including the Parsons and Sclater (PSM) model, Global Depth and Heat (GDH1) model and Constant Heat flow Applied on the Bottom Lithospheric Isotherm (CHABLIS) model, have been used to predict heat flow in the ocean lithosphere. The discrepancy between the predicted and measured heat flow in the younger lithosphere (i.e. younger than 55 Myr) influenced by local hydrothermal circulation has been used to estimate hydrothermal heat flux and investigate hydrothermal processes. We can modify the cooling models by substituting the ordinary mass density of lithosphere by fractal density with singularity. This new model provides a modified solution to fit the observed heat flow data used in other models in the literature throughout the age range. This model significantly improves the results for prediction of heat flow that were obtained using the PSM, GDH1 and CHABLIS models. Furthermore, the heat flow model does not exhibit special characteristics around any particular age of lithosphere. This raises a fundamental question about the existence of a "sealing" age and accordingly the hydrothermal flux estimation based on the cooling models.
RESUMEN
Objective To understand the prevalence of alcohol dependence in individuals living in Guangxi Zhuang Autonomous Region,China. Methods From July 2007 to December 2007,21290 subjects aged more than 15 were randomly selected for 6 Prefecture-level cities and 10 counties by stratified multi-stage cluster sampling method. All subjects were investigated by face to face interview. The Chinese version of Composite International Diagnostic Interview (CIDI3.0) Provided by the Chinese Center for Disease Control And Prevention was used as the screening tool and the diagnoses were made with the 10th edition of international classification of Disease Criteria. Results 18 219 subjects completed the screening,the Completion rate was 85.58‰. The general point prevalence and the general lifetime prevalence of alcohol dependence in individuals living in Guangxi was both 4.50‰. The general lifetime prevalence was higher in rural (6.17‰) than in urban (1.85‰) ( RR =0.31,95% CI =0. 17 ～0.57, P=0. 000) ,higher in men (8.59‰) than in women (0. 33‰) ( RR =0.04,95% CI =0. 01 ～ 0.13, P = 0.000 ) and higher in Zhuang (9.63‰) than in Han(1.95‰) ( RR = 5. 01,95% CI = 3.02 ～8.34, P = 0.000). The lifetime prevalence of alcohol dependence tends upwards as age increasing (P＜0.05 ) and it differs in different marital status,higher in divorce groups (P ＜ 0.05). Conclusion Schizophrenia, Depression disorder, Alcohol dependence disorder are the most common mental disorders and have become the public health problem in Guangxi. To do this,it is necessary to carry out targeted research in prevention and rehabilitation.