Membranes,mitochondria and amoebae: shape models

Most real-world shapes and images are characterized by high variability- they are not rigid, like crystals, for example—but they are strongly structured. Therefore, a fundamental task in the understanding and analysis of such image ensembles is the construction of models that incorporate both variability and structure in a mathematically precise way. The global shape models introduced in Grenander's general pattern theory are intended to do this. In this paper, we describe the representation of two-dimensional mitochondria and membranes in electron microscope photographs, and three-dimensional amoebae in optical sectioning microscopy. There are three kinds of variability to all of these patterns, which these representations accommodate. The first is the variability in shape and viewing orientation. For this, the typical structure is represented via linear, circular and spherical templates, with the variability accomodated via the application of transformations applied to the templates. The transformations form groups: scale, rotation and translation. They are locally applied throughout the continuum and of high dimension. The second is the textural variability; the inside and outside of these basic shapes are subject to random variation, as well as sensor noise. For this, statistical sensor models and Markov random field texture models are used to connect the constituent structures of the shapes to the measured data. The third variability type is associated with the fact that each scene is made up of a variable number of shapes; this number is not assumed to be known a priori. Each scene has a variable number of parameters encoding the transformations of the templates appropriate for that scene. For this, a single posterior distribution is defined over the countable union of spaces representing models of varying numbers of shapes. Bayesian inference is performed via computation of the conditional expectation of the parametrically defined shapes under the posterior. These conditional mean estimates are generated using jump-diffusion processes. Results for membranes, mitochondria and amoebae are shown.     

Equality Management – Towards a Materialist Approach

Attempts to redefine equality initiatives to fit squarely within the enterprise culture serve only to mask an ongoing conceptual confusion in the area of equality management. This theoretical article attempts to show that this conceptual confusion lies within the narrowness of approaches which address labour market inequalities from both an equality of opportunity and an equality of outcome perspective. The inability of these perspectives to satisfactorily address systemic causes of labour market inequalities pulls our attention towards a more materialist approach which may be found (this side of a capitalist/patriarchal society) within an equality of condition frame of reference. This widens the perspective from which equality management can be pursued so that measures to address the differential distribution of resources, rewards, opportunities and treatment in the workplace are informed by all three equalities: opportunity, outcome and conditions. Such a theoretical approach is inevitably limited in that it only provides a framework for addressing those who are in paid employment, i.e. seeks to reform the capitalist/patriarchal system. However, by posing questions of the crucial pillars of such systems notably status, reward and with that power, the ‘long’ and ‘radical’ agendas of the equality project may once again be picked up.     

Perspectives on Cancer Prevention

Cancer prevention is a major component of cancer control, which also comprises screening, treatment, rehabilitation and palliative care. Preventive approaches need to be congruent with those adopted for other chronic diseases, with a major impact in reduction of incidence and mortality of many common cancers to be expected from smoking control and dietary modification. Increasing interest is now being paid to other environmental causes of cancer, and to gene-environment interactions. However, one of the major research needs remains the evaluation of better ways to convince people to make the necessary changes in their lifestyle that will reduce their risk of cancer.     

Scarcity,Income Advantage,and Mobility: More Evidence on the Functional Theory of Stratification*

Two testable propositions suggested in the Davis and Moore functional theory of stratification are examined: the effect of scarcity on rewards and the effect of higher rewards on mobility. Data on the occupation of public school teaching for the period 1930 to 1971 were analyzed and compared with other wage and salary workers during those years. The proposition that scarcity increases rewards is rejected by these data, because higher incomes occur during periods (1) when there was less scarcity of teachers and (2) when employers discriminated against qualified married females in their hiring practices. The proposition that an increase in income advantage increases the movement of more qualified personnel into those positions found support, but for reasons more consistent with a conflict than a functional explanation. This research demonstrates the importance of economic incentives in attracting personnel but more importantly it documents how “political” groupings can regulate market forces.     

Economic feasibility of a primary care practice

To make informed career decisions, the new physician must acquire basic skills in medical management and health care economics and learn how to evaluate the potential survival and growth of a primary care practice. The authors have developed a model designed to aid physicians in determining the economic feasibility of establishing a practice in a specific community or joining an established practice.     

Female marital mobility within Northern Ireland and the Republic of Ireland: a log-linear analysis

A series of log-linear models predicting the exchange marital experiences of Irish wives are prevented for the Irish Republic. The best explanatory model is one in which the relationship between a husband's occupational status and that of his father-in-law remains homogeneous across age levels, Women show a marked propensity to marry husbands at a similar occupational status as that of their fathers and long-range upward or downward mobility across the manual/nonmanual divide is unlikely. This tendency towards endogamy is particularly pronounced within the two upper non-manual categories and the manual strata generally the same general model of homogeneous association holds for Northern Ireland across age levels and religious affiliation. In the North, however, more short-range mobility occurs, particularly between the two upper non-manual groups. Despite this the norm for both the Irish Republic and Northern Ireland is marital immobility rather than marital mobility with no evidence of a fundamental trend towards increased marital mobility. Furthermore. The mobility through marriage that did occur does not result in an overall net advantage for women.     

Double machine operation and psychological strain

This study examines the effects of double machine operation on psychological strain. CNC drilling machine operators' reactions to their job were monitored as they rotated between three different work conditions; single machine operation, double machine operation, and double machine operation with additionally high responsibility for products. Results show no effect of double machine operation on strain where responsibility was low. Double machine operation under the condition of high responsibility, however, was found to increase strain.     

The Japanese management theory jungle

Many competing hypotheses have been advanced to account for the apparent effectiveness of Japanese management practices. The present review of some of the leading theories attempts to classify and clarify the state of knowledge of Japanese management. Although each theory may be correct as a partial explanation of Japan's success, no single conceptualization has captured the complexity of Japan's managerial achievement. Further development of integrated, internally consistent models is needed.     

Human Capital,Social Support,and Economic Well-being among Rural,Low-income Mothers: A Latent Growth Curve Analysis

The purpose of this study was to better understand human capital and social support in the long-term economic well-being of rural, low-income mothers in the US. Three waves of data from a multi-state, longitudinal investigation tracking the well-being of rural families, known as “Rural Families Speak,” were used to test two latent growth curve models of economic well-being. Results indicated that human capital alone is not a good predictor of economic well-being over time for this sample. A model of economic well-being that includes both social support and human capital provides a better fit for these data. Findings suggest that social support is a key contributor to long-term economic success for this sample. Implications for public policy are presented.