Hysteresis phenomenon in deterministic traffic flows

We study phase transitions of a system of particles on the one-dimensional integer lattice moving with constant acceleration, with a collision law respecting slower particles. This simple deterministic ``particle-hopping'' traffic flow model being a straightforward generalization to the well known Nagel-Schreckenberg model covers also a more recent slow-to-start model as a special case. The model has two distinct ergodic (unmixed) phases with two critical values. When traffic density is below the lowest critical value, the steady state of the model corresponds to the ``free-flowing'' (or ``gaseous'') phase. When the density exceeds the second critical value the model produces large, persistent, well-defined traffic jams, which correspond to the ``jammed'' (or ``liquid'') phase. Between the two critical values each of these phases may take place, which can be interpreted as an ``overcooled gas'' phase when a small perturbation can change drastically gas into liquid. Mathematical analysis is accomplished in part by the exact derivation of the life-time of individual traffic jams for a given configuration of particles.Comment: 22 pages, 6 figures, corrected and improved version, to appear in the Journal of Statistical Physic

Migrant health in Italy: a better health status difficult to maintain-country of origin and assimilation effects studied from the Italian risk factor surveillance data

Many studies on migrant health have focused on aspects of morbidity and mortality, but very few approach the relevant issues of migrants' health considering behavioral risk factors. Previous studies have often been limited methodologically because of sample size or lack of information on migrant country of origin. Information about risk factors is fundamental to direct any intervention, particularly with regard to non-communicable diseases that are leading causes of death and disease. Thus, the main focus of our analysis is the influence of country of origin and the assimilation process

Mental health of female foreign spouses in transnational marriages in southern Taiwan

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate the mental health status, and the risk factors associated with mild psychiatric disorders, of female foreign spouses (from Vietnam, Indonesia, and mainland China) in southern Taiwan, and to understand the mental health needs of these women.</p> <p>Methods</p> <p>One hundred and twenty nine participants were willing to participate in this study. All participants fulfilled all questionnaires which included demographic information, the Chinese Health Questionnaire (CHQ), the Eysenck Personality Questionnaire (EPQ), and the Mental Health Care Needs Questionnaire (MHCNQ).</p> <p>Results</p> <p>By multiple linear regression, neuroticism characteristics (p = 0.000), the dimension of knowledge of the level of their own psychological disturbance (p = 0.001), dimension of friends assistance (p = 0.033), and dimension of religion comfort (p = 0.041) in mental health care needs could be used to predict possible mild psychiatric disorders. Furthermore, SEM model showed that Indonesian or Vietnamese spouses have more likely degree in mental health care needs (β = -0.24, <it>p </it>= 0.003), compared with Chinese ones. A higher level of neuroticism was associated with a greater likelihood of mild psychiatric disorder (β = 0.54, <it>p </it>< 0.001), and of mental health care needs (β = 0.21, <it>p </it>= 0.013). A higher degree of mental health care needs was related to a greater likelihood of mild psychiatric disorder (β = 0.14, <it>p </it>= 0.05).</p> <p>Conclusion</p> <p>In conclusion, we have obtained a better understanding of the mental health status of female foreign spouses in transnational marriages, who face many difficulties. Indonesian or Vietnamese spouses tend to more likely degree in mental health care needs than Chinese spouses, and then indirectly influenced their mental health status. Some individuals with a neurotic personality are exposed to high risk and might suffer from mild psychiatric symptoms. The needs for psychological counseling and religion therapy were the first priority for these women, particularly the Indonesian and Vietnamese spouses. From these findings, we have a better understanding of how to assist these female foreign spouses in future.</p

Perceived need for mental health care among non-western labour migrants

Background There is a supposed higher prevalence of common mental disorders among many migrant groups. At the same time, problems are reported regarding underutilisation of mental health services by migrants. Since perceived need for care is a powerful predictor of actual care utilisation, we aimed to study the hypothesis that, given the same level of mental morbidity, non-Western migrants would perceive less need for mental health care than ethnic Dutch residents. Additionally, we studied the extent to which needs are met in both groups, as well as several possible barriers to care. Methods A cross-sectional study with data from the 2004/2005 Amsterdam Health Monitor. Data were complete from 626 ethnic Dutch and non-Western (Turkish and Moroccan) labour migrants. Respondents participated in a structured interview in their own language, which included the perceived need for care questionnaire (PNCQ) and the composite international diagnostic interview (CIDI) version 2.1 for anxiety and depressive disorders. Results Perceived need was much higher among Turkish migrants. Among Moroccans the perceived need was comparable to ethnic Dutch. Turkish migrants also reported that needs were met less often than ethnic Dutch. Differences were explained by a higher prevalence of common mental disorders and higher symptom levels among Turkish. When differences in mental morbidity were taken into account, Moroccans perceived less need for information, drugs, referral to specialised mental health care, or for counselling. The most important barrier to care in all ethnic groups was the preference to solve the problem on one’s own. Conclusion In case of similar mental morbidity, perceived need for care was lower than among ethnic Dutch. The results did not support the hypothesis that in case of similar mental distress, needs of migrants were less often met than needs of ethnic Dutch

Uptake of health services for common mental disorders by first-generation Turkish and Moroccan migrants in the Netherlands

Abstract Background Migration and ethnic minority status have been associated with higher occurrence of common mental disorders (CMD), while mental health care utilisation by non-Western migrants has been reported to be low compared to the general population in Western host countries. Still, the evidence-base for this is poor. This study evaluates uptake of mental health services for CMD and psychological distress among first-generation non-Western migrants in Amsterdam, the Netherlands. Methods A population-based survey. First generation non-Western migrants and ethnic Dutch respondents (N = 580) participated in structured interviews in their own languages. The interview included the Composite International Diagnostic Interview (CIDI) and the Kessler psychological distress scale (K10). Uptake of services was measured by self-report. Data were analysed using weighting techniques and multivariate logistic regression. Results Of subjects with a CMD during six months preceding the interview, 50.9% reported care for mental problems in that period; 35.0% contacted specialised services. In relation to CMD, ethnic groups were equally likely to access specialised mental health services. In relation to psychological distress, however, Moroccan migrants reported less uptake of primary care services (OR = 0.37; 95% CI = 0.15 to 0.88). Conclusion About half of the ethnic Dutch, Turkish and Moroccan population in Amsterdam with CMD contact mental health services. Since the primary purpose of specialised mental health services is to treat "cases", this study provides strong indications for equal access to specialised care for these ethnic groups. The purpose of primary care services is however to treat psychological distress, so that access appears to be lower among Moroccan migrants