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There are large between-country differences in measures of economic and noneconomic well-being. Many researchers view increasing the stock of human capital as the key to raising economic development, promoting democratization, and improving health, and hence improving overall societal well-being. The single most studied aspect of human capital concerns cognitive competence. Differences in population cognitive competence might explain these societal differences. Evidence suggests that education builds cognitive competence, and education and cognitive competence promote better social outcomes, in terms of both economic and noneconomic factors. However, measuring population cognitive competence for countries requires representative samples, culture-fair tests, equivalency in the relationship between test measures and other cognitive attributes, and comparability in testing situations. In most cases, none of this has been achieved.
While depression is a growing public health issue, the percentage of individuals with depression receiving treatment is low. Physical and social attributes of the neighborhood may influence the level of depressive symptoms and the prevalence of depression in older adults.
This review systematically examined the literature on neighborhood environmental correlates of depression in older adults. Findings were analyzed according to three depression outcomes: depressive symptoms, possible depression, and clinical depression. Based on their description in the article, environmental variables were assigned to one of 25 categories. The strength of evidence was statistically quantified using a meta-analytical approach with articles weighted for sample size and study quality. Findings were summarized by the number of positive, negative, and statistically non-significant associations by each combination of environmental attribute – depression outcome and by combining all depression outcomes.
Seventy-three articles met the selection criteria. For all depression outcomes combined, 12 of the 25 environmental attribute categories were considered to be sufficiently studied. Three of these, neighborhood socio-economic status, collective efficacy, and personal/crime-related safety were negatively associated with all depression outcomes combined. Moderating effects on associations were sparsely investigated, with 52 articles not examining any. Attributes of the physical neighborhood environment have been understudied.
This review provides support for the potential influence of some neighborhood attributes on population levels of depression. However, further research is needed to adequately examine physical attributes associated with depression and moderators of both social and physical neighborhood environment attribute – depression outcome associations.
Differences between verbal and non-verbal cognitive development from childhood to adulthood may differentiate between those with and without psychotic symptoms and affective symptoms in later life. However, there has been no study exploring this in a population-based cohort.
The sample was drawn from the MRC National Survey of Health and Development, and consisted of 2384 study members with self-reported psychotic experiences and affective symptoms at the age of 53 years, and with complete cognitive data at the ages of 8 and 15 years. The association between verbal and non-verbal cognition at age 8 years and relative developmental lag from age 8 to 15 years, and both adult outcomes were tested with the covariates adjusted, and mutually adjusted for verbal and non-verbal cognition.
Those with psychotic experiences [thought interference (n = 433), strange experience (n = 296), hallucination (n = 88)] had lower cognition at both the ages of 8 and 15 years in both verbal and non-verbal domains. After mutual adjustment, lower verbal cognition at age 8 years and greater verbal developmental lag were associated with higher likelihood of psychotic experiences within individuals, whereas there was no association between non-verbal cognition and any psychotic experience. In contrast, those with case-level affective symptoms (n = 453) had lower non-verbal cognition at age 15 years, and greater developmental lag in the non-verbal domain. After adjustment, lower non-verbal cognition at age 8 years and greater non-verbal developmental lag were associated with higher risk of case-level affective symptoms within individuals.
These results suggest that cognitive profiles in childhood and adolescence differentiate psychiatric disease spectra.
Higher lifetime antipsychotic exposure has been associated with poorer cognition in schizophrenia. The cognitive effects of adjunctive psychiatric medications and lifetime trends of antipsychotic use remain largely unclear. We aimed to study how lifetime and current benzodiazepine and antidepressant medications, lifetime trends of antipsychotic use and antipsychotic polypharmacy are associated with cognitive performance in midlife schizophrenia.
Sixty participants with DSM-IV schizophrenia from the Northern Finland Birth Cohort 1966 were examined at 43 years of age with an extensive cognitive test battery. Cumulative lifetime and current use of psychiatric medications were collected from medical records and interviews. The associations between medication and principal component analysis-based cognitive composite score were analysed using linear regression.
Lifetime cumulative DDD years of benzodiazepine and antidepressant medications were not significantly associated with global cognition. Being without antipsychotic medication (for minimum 11 months) before the cognitive examination was associated with better cognitive performance (P = 0.007) and higher lifetime cumulative DDD years of antipsychotics with poorer cognition (P = 0.020), when adjusted for gender, onset age and lifetime hospital treatment days. Other lifetime trends of antipsychotic use, such as a long antipsychotic-free period earlier in the treatment history, and antipsychotic polypharmacy, were not significantly associated with cognition.
Based on these naturalistic data, low exposure to adjunctive benzodiazepine and antidepressant medications does not seem to affect cognition nor explain the possible negative effects of high dose long-term antipsychotic medication on cognition in schizophrenia.
Recurrent affective problems are predictive of cognitive impairment, but
the timing and directionality, and the nature of the cognitive
impairment, are unclear.
To test prospective associations between life-course affective symptoms
and cognitive function in late middle age.
A total of 1668 men and women were drawn from the Medical Research
Council National Survey of Health and Development (the British 1946 birth
cohort). Longitudinal affective symptoms spanning age 13–53 years served
as predictors; outcomes consisted of self-reported memory problems at
60–64 years and decline in memory and information processing from age 53
to 60–64 years.
Regression analyses revealed no clear pattern of association between
longitudinal affective symptoms and decline in cognitive test scores,
after adjusting for gender, childhood cognitive ability, education and
midlife socioeconomic status. In contrast, affective symptoms were
strongly, diffusely and independently associated with self-reported
Affective symptoms are more clearly associated with self-reported memory
problems in late midlife than with objectively measured cognitive
Large scale, international clinical trials are formidable challenges, but they are the most effective means of answering important clinical questions in a definitive, generalizable manner. They require adequate funding and must be rigorously conducted. Much can be gleaned from such studies, which address the important research questions and provide answers to related questions. Such trials are enormously rewarding and are worth the expense and effort.
For optical fields the notion of a total angular momentum has long been known. The concept of a light beam carrying orbital angular momentum, however, was unfamiliar until it was discovered that Laguerre-Gaussian beams, within the paraxial approximation, carry a well-defined orbital angular momentum [1, 2]. This discovery started the modern interest in orbital angular momentum of light. In this chapter we discuss the theoretical framework of orbital angular momentum of light in terms of fields and light beams and how to generate these. The material in this chapter is based in parts on the PhD thesis of Götte .
A quantitative treatment of the mechanical effects of light became possible only after light had been integrated into Maxwell's dynamical theory of electromagnetic waves. With this theory Poynting  derived a continuity equation for the energy in the electromagnetic field. After Heaviside [5, 6] introduced the vectorial notation for the Maxwell equations this continuity equation could be written in its modern form using the Poynting vector. Interestingly, the linear momentum density in the electromagnetic field is also given by the Poynting vector apart from constant factors depending on the chosen system of units. Poynting  also derived an expression for the angular momentum of circularly polarised light by means of a mechanical analogue in the form of a rotating shaft. Later, Poynting's expression was verified by measuring the torque on a quarter wave-plate due to circularly polarised light .
The quantum mechanical description of the azimuthal rotation angle and the orbital angular momentum around the polar axis differs greatly from the description of position and momentum. This has led to a controversy over the existence of a self-adjoint angle operator in the literature. It is possible to circumvent the problems of defining a self-adjoint operator for a periodic variable by using trigonometric functions of operators as a basis for the quantum mechanical description. This approach, however, does not allow us to study the properties of the angle operator itself. By using a state space of an arbitrarily large yet finite number of dimensions, it is possible to introduce angle and orbital angular momentum as a conjugate pair of variables both represented by Hermitian matrices. After physical and measurable quantities have been calculated in this state space the number of dimensions is allowed to tend to infinity in a limiting procedure.
The first part of this chapter reviews the difficulties associated with the quantum mechanical formulation of angle and orbital angular momentum and presents a way to overcome these problems using a finite-dimensional state space. In the second part this formulation is generalised to include the phenomenon of non-integer orbital angular momentum. This part is based on a chapter of the PhD thesis of Götte , where further details may be found.
The correct description of a periodic variable such as a rotation angle or the optical phase has been a long standing problem in quantum mechanics. At the root of the problem is the question of whether the variable itself is restricted in a 2π radian range or whether it evolves continuously without bound.
The aim of this study was to estimate the amount of childhood hepatitis B virus transmission in children born in the UK, a very low-prevalence country, that is preventable only by universal hepatitis B immunization of infants. Oral fluid specimens were collected from schoolchildren aged 7–11 years in four inner city multi-ethnic areas and tested for the presence of antibody to hepatitis B core antigen (anti-HBc). Those found positive or indeterminate were followed up with testing on serum to confirm their hepatitis B status. The overall prevalence of anti-HBc in children was low [0·26%, 95% confidence interval (CI) 0·14–0·44]. The estimated average annual incidence of hepatitis B was estimated to be 29·26/100 000 children (95% CI 16·00–49·08). The total incidence that is preventable only by a universal infant immunization programme in the UK was estimated to be between 5·00 and 12·49/100 000. The study demonstrates that the extent of horizontal childhood hepatitis B virus transmission is low in children born in the UK and suggests that schools in the UK are an uncommon setting for the transmission of the virus. Targeted hepatitis B testing and immunization of migrants from intermediate- and high-prevalence countries is likely to be a more effective measure to reduce childhood transmission than a universal infant immunization programme.
Inflammatory bowel disease (IBD) is a collective term for conditions characterised by chronic inflammation of the gastrointestinal tract involving an inappropriate immune response to commensal micro-organisms in a genetically susceptible host. Previously, aqueous and ethyl acetate extracts of gold kiwifruit (Actinidia chinensis) or green kiwifruit (A. deliciosa) have demonstrated anti-inflammatory activity using in vitro models of IBD. The present study examined whether these kiwifruit extracts (KFE) had immune-modulating effects in vivo against inflammatory processes that are known to be increased in patients with IBD. KFE were used as a dietary intervention in IL-10-gene-deficient (Il10− / −) mice (an in vivo model of IBD) and the C57BL/6J background strain in a 3 × 2 factorial design. While all Il10− / − mice developed significant colonic inflammation compared with C57BL/6J mice, this was not affected by the inclusion of KFE in the diet. These findings are in direct contrast to our previous study where KFE reduced inflammatory signalling in primary cells isolated from Il10− / − and C57BL/6J mice. Whole-genome gene and protein expression level profiling indicated that KFE influenced immune signalling pathways and metabolic processes within the colonic tissue; however, the effects were subtle. In particular, expression levels across gene sets related to adaptive immune pathways were significantly reduced using three of the four KFE in C57BL/6J mice. The present study highlights the importance of investigating food components identified by cell-based assays with appropriate in vivo models before making dietary recommendations, as a food that looks promising in vitro may not be effective in vivo.
This chapter presents evidence that mechanisms relating to the cognitive unconscious: mental structures, processes, and states that can influence experience, thought, and actions outside phenomenal awareness and voluntary control make an important contribution to intelligent behavior. There have been some recent studies that look at individual differences in the cognitive unconscious. The chapter focuses on individual differences and reviews recent empirical work on relations among the cognitive processes underlying psychometric intelligence and the cognitive processes underlying the cognitive unconscious, attempting to bridge two major research programs that, until recently, have traveled on separate but parallel paths. The dual-process theory of human intelligence aims to integrate modern dual-process theories of cognition with research on intelligence. By fostering collaborations across the various areas of psychology and related disciplines, and incorporating dual-process theory into thinking, one should be able to come to a fuller, more complete understanding of human intelligence.