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A positive correlation was observed between the enantiomeric excess (ee) of L-isovaline (L-iVal) and the degree of aqueous alteration (AqA) of carbonaceous meteorites. The origin of this remarkable phenomenon has remained enigmatic from two points of view: First, the correlation is between seemingly unrelated observables-nothing about AqA is of chiral characteristics; and second, following the accepted assumption that circularly polarized light (CPL) was the origin of the observed meteoritic ee of L-amino acids (AAs), it remined unclear why some of the observed levels of the ee of L-iVal in that correlation are significantly higher than those observed in laboratory simulations or those obtained from circular dichroism (CD) g-factor calculations. The current proposition accounting for this picture attributes late AqA conditions of the meteoritic parent bodies as providing the grounds for amplification of early initially CPL-generated low levels of L-ee. For reasons summarized below, this interpretation, which treats the CPL event and the AqA process as occurring in wide-time separated eras, is re-visited. An alternative interpretation of the observed correlation and of the high ee-values, is provided. It focuses on hydrophilic dust-aggregates clouds in wet star-forming regions in early presolar times, where both the CPL event and the grounds leading to the later AqA processes of the parent bodies, occurred. This mechanism removes the time separation between the initial ee formation and the AqA of the parent body, and replaces it with parallel processes, providing a scenario to the observation of high ee's without total destruction, and to the apparent AqA/L-ee correlation. Although iVal is at the focus of this report, the steps of the development of the alternative mechanism and the conclusions that arise from it, are relevant and applicable to the general observations of L-ee's of meteoritic AA's. [ABSTRACT FROM AUTHOR]

This paper questions the validity of allegations by the General Accounting Office in 1979 that OSHA was then allocating more of its resources to investigating worker complaints than the quality of those complaints warranted. Specifically, the author finds that complaint-initiated inspections and "general schedule" inspections (those made on the basis of targeting criteria developed by OSHA) were similarly productive in uncovering safety violations in 1977-79. The findings also suggest that the interindustry distribution of complaints closely matched the distribution of general schedule inspections; complaints were not used by unionized workers as a weapon in negotiations; and the 1980 changes in complaint handling that were enacted in response to the GAO's report did not improve the "yield" of complaint-initiated inspections relative to that of general schedule inspections. [ABSTRACT FROM AUTHOR]

Turbulent premixed flames often experience thermoacoustic instabilities when the combustion heat release rate is in phase with acoustic pressure fluctuations. Linear methods often assume a priori that oscillations are periodic and occur at a dominant frequency with a fixed amplitude. Such assumptions are not made when using nonlinear analysis. When an oscillation is fully saturated, nonlinear analysis can serve as a useful avenue to reveal flame behaviour far more elaborate than period-one limit cycles, including quasi-periodicity and chaos in hydrodynamically or thermoacoustically self-excited system. In this paper, the behaviour of a bluff-body stabilised turbulent premixed propane/air flame in a model jet-engine afterburner configuration is investigated using computational fluid dynamics. For the frequencies of interest in this investigation, an unsteady Reynolds-averaged Navier–Stokes approach is found to be appropriate. Combustion is represented using a modified laminar flamelet approach with an algebraic closure for the flame surface density. The results are validated by comparison with existing experimental data and with large eddy simulation, and the observed self-excited oscillations in pressure and heat release are studied using methods derived from dynamical systems theory. A systematic analysis is carried out by increasing the equivalence ratio of the reactant stream supplied to the premixed flame. A strong variation in the global flame structure is observed. The flame exhibits a self-excited hydrodynamic oscillation at low equivalence ratios, becomes steady as the equivalence ratio is increased to intermediate values, and again exhibits a self-excited thermoacoustic oscillation at higher equivalence ratios. Rich nonlinear behaviour is observed and the investigation demonstrates that turbulent premixed flames can exhibit complex dynamical behaviour including quasiperiodicity, limit cycles and period-two limit cycles due to the interactions of various physical mechanisms. This has implications in selecting the operating conditions for such flames and for devising proper control strategies for the avoidance of thermoacoustic instability. [ABSTRACT FROM AUTHOR]

The article discusses a study about the estimation of the 12-week remission ratio of patients with depressive syndrome and its determinants in a normal clinical environment in South Korea. The result shows that from 723 subjects, the 12-week remission percentage is 31.4%. The remission is more probably to happen in women, in patients with no previous account of suicide attempt, and those with lesser baseline uneasiness. The findings provide that remission linked with unlimited clinical interference was analogous to STAR*D assessment for citalopram.

Background. Previous studies have examined suicidal ideation in older populations and emphasized the strong association with the presence of psychiatric disorder. However, associations with the presence of psychiatric disorder across the age range are unclear. Representative epidemiological estimates are needed.Method. In a national survey of psychiatric morbidity in Great Britain, 8580 randomly selected adults were interviewed. Three questions were asked to assess suicidal ideation, and psychiatric disorder was identified using the revised Clinical Interview Schedule (CIS-R).Results. Suicidal ideation was up to three times commoner in younger adults than in those aged 55–74 years but the odds of depression in those with suicidal thoughts was significantly greater in the older age group (p<0·01). Tiredness with life (p<0·01) and thoughts of death (p<0·01) were also more strongly associated with depression in the older age group. Other major associations of suicidal ideation for all ages were: smaller social support group, being divorced or separated, poor self-rated general health, and limitations in activities of daily living (ADL). Being single was an important factor for younger age groups, and widowhood for older people. Life events were also important in younger people, but not in those aged 55–74 years.Conclusions. Suicidal thoughts and death wishes are comparatively more unusual in older people; however, they are more likely to be associated with clinical depression. In terms of suicide prevention this study emphasizes the importance of improving rates of recognition and treatment of depression in older people. [ABSTRACT FROM AUTHOR]

Background. Previous studies suggest that worry content and prevalence may vary as a function of age, but evidence is limited.Method. Cross-sectional national survey of 8580 householders in Great Britain aged between 16 and 74 years. This analysis examined the relationship between age, worry content (relationships/family, financial/housing, work, health, miscellaneous), common mental disorders, and functional limitation, adjusting for other sociodemographic factors.Results. Overall, the prevalence of worries declined with age. However, with the exception of worry about relationships, the strength of associations between worry types and mental disorder either remained constant or increased in the older age groups. Compared to the 16–24 years reference group, worries about relationships/family, finances/housing and work were lower in the 55–74 years age groups. Financial/housing worries were increased in the 25–44 years group, and health worries were increased in the 25–64 years groups. There were independent associations between all worry items and the categories of mental disorder. All worry types apart from miscellaneous worries were independently associated, positively or negatively, with functional limitation.Conclusions. Worry content in the general population varies as a function of age, gender, marital status, and educational attainment. All categories of worry are more prevalent in individuals with common mental disorders. The lower prevalence of worries and their stronger association with mental disorder in old age emphasize the clinical significance of these symptoms in this age group. [ABSTRACT FROM AUTHOR]

This work probes the variability in G7 cohesion in response to relatively new disturbances in the international system. Using a domestic politics model, we argue that G7 cohesion weakens in the face of international terrorism in the context of variable domestic consequences to common foreign policy responses to this systemic disturbance. We compare the predictions from our model with predictions stemming from neorealist and liberal/institutionalist explanations. We find that, consistent with the domestic politics explanation, G7 foreign policy cohesion declines as internal terrorism increases. [ABSTRACT FROM AUTHOR]

Influenza viral infection induces increases in non-rapid eye movement sleep and decreases in rapid eye movement sleep in normal mice. An array of cytokines is produced during the infection, and some of them, such as IL-1β and TNF-α, are well-defined somnogenic substances. It is suggested that nitric oxide (NO) may mediate the sleep-promoting effects of these cytokines. In this study, we use mice with targeted disruptions of either the neuronal NO synthase (nNOS) or the inducible NO synthase (iNOS) gene, commonly referred to as nNOS or iNOS knockouts (KOs), to investigate sleep changes after influenza viral challenge. We report that the magnitude of viral-induced non-rapid eye movement sleep responses in both nNOS KOs and iNOS KOs was less than that of their respective controls. In addition, the duration of rapid eye movement sleep in nNOS KO mice did not decrease compared with baseline values. All strains of mice had similar viral titers and cytokine gene expression profiles in the lungs. Virus was not isolated from the brains of any strain. However, gene expression in the brain stem differed between nNOS KOs and their controls: mRNA for the interferon-induced gene 2',5'-oligoadenylate synthase la was elevated in nNOS KOs relative to their controls at 15 h, and IL-1β mRNA was elevated in nNOS KOs relative to their controls at 48 h. Our results suggest that NO synthesized by both nNOS and iNOS plays a role in virus-induced sleep changes and that nNOS may modulate cytokine expression in the brain. [ABSTRACT FROM AUTHOR]

Numbers of older people are increasing rapidly in many developing nations and there is a pressing need for epidemiological studies of psychiatric morbidity, particularly dementia. Valid methods for case identification are an important first step. The Geriatric Mental State (GMS) is a widely used diagnostic instrument but has received little formal evaluation in developing nations. The objective of this study was to investigate the screening properties of GMS organic disorder with respect to clinically diagnosed dementia in an older Korean population, about half of whom have received no formal education. 746 people aged 65+ in Kwangju, South Korea who were participants in a community survey of psychiatic morbidity, completed a GMS interview (with diagnoses assigned through the AGECAT computerised algorithm) and, independently, received a clinical assessment for dementia. GMS organic disorder was diagnosed in 262 participants (35%) and DSM-IV dementia in 110 (15%). Increased age, female gender and lower education independently predicted disagreement between the two diagnoses. In these groups, GMS sensitivity to a clinical diagnosis of dementia remained high but specificity was markedly reduced. Dementia may be overestimated in developing nations if the GMS-AGECAT diagnosis of organic disorder is used alone. The validity of other diagnoses, such as affective disorder, may also be affected if the hierarchical diagnostic algorithm is used (i.e. where the diagnosis of organic disorder affects the likelihood of other diagnoses). Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Develops a method for assessing cohesion in the Group of Seven (G-7) nations and apply it to systematically describe trends in G-7 cohesion since 1975 in the United Nations General Assembly. Empirical methods to assess cohesion in policy preferences between G-7 states; Disagreement between the United States and other G-7 members.

This article presents information regarding compensating differentials for pensions and under-funding in the public sector. It tests the theory of compensating wage differentials as it relates to two aspects of pensions, the overall generosity of promised benefits and the certainty of receipt. Because pensions are both large and variable, and because more generous and more assured pension benefits are clearly desirable, ceteris paribus, tests of the theory in the context of pension are likely to be reasonably credible. The starting point for a modern treatment of compensating wage differentials is hedonic price theory, perhaps most completely. Hedonic analysis views employers and employees as jointly choosing employment characteristics, including wages, which maximize their objective functions. Insights about the relationship between wages and a particular employment characteristic are generated by assuming all other characteristics are already determined and performing the usual partial analysis. The results of all these estimates strongly suggest the presence of compensating wage differentials for both pension promises and under-funding. These estimated differentials, moreover, are insignificantly different from the magnitude suggested by theory.

This paper estimates the effects of OSHA inspections on injury rates at the plant level. The methodology involves comparing injury rates of plants inspected "early" in a given year with those inspected "late" in the year, after controlling for prior injury rates and other factors. The results suggest that OSHA inspections in 1973 reduced injury rates by about 16 percent, but that 1974 inspections had no statistically significant impact. [ABSTRACT FROM AUTHOR]

The article focuses on federal regulation related to health and safety in the U.S. The Occupational Safety and Health Act was passed in 1970 without any systematic discussion of three fundamental issues: (1) how much risk of injury and disease should be removed from the workplace; (2) how necessary it is for the government to intervene to encourage the socially desirable level of risk; and (3) the most efficient mode of governmental intervention. Judging from the near unanimous decisions in both Senate and House, virtually everyone in Congress believed a detailed set of safety and health standards was required to accomplish the legislative goal of reducing occupational hazards to the technologically feasible minimum. As a result, society has been saddled with a law, which, in large part, is of dubious necessity and is inefficiently attempting to do the irrational. Safety and health protection ought to be provided so long as the beneficiaries are willing to pay for it. This criterion is not inhumane or callous. Resources to satisfy human wants are scarce, and if such resources are used to satisfy some wants they cannot be used to satisfy others.

Addresses issues in occupational health programs of government. Tax approach; Importance of government provision of information; Reliance on standards approach.

Discusses ways on how to stimulate greater occupational safety in the U.S. Provision of workers and employers with information concerning risks and their prevention; Imposition of financial penalties on employers when a work injury occurs; Requirement for employers to abide by a detailed set of safety standards; Implications on laws governing occupational safety and health.