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We determined the macroscopic limit for phase synchronization of cellular clocks in an artificial tissue created by a “big chamber” microfluidic device to be about 150,000 cells or less. The dimensions of the microfluidic chamber allowed us to calculate an upper limit on the radius of a hypothesized quorum sensing signal molecule of 13.05 nm using a diffusion approximation for signal travel within the device. The use of a second microwell microfluidic device allowed the refinement of the macroscopic limit to a cell density of 2166 cells per fixed area of the device for phase synchronization. The measurement of averages over single cell trajectories in the microwell device supported a deterministic quorum sensing model identified by ensemble methods for clock phase synchronization. A strong inference framework was used to test the communication mechanism in phase synchronization of quorum sensing versus cell-to-cell contact, suggesting support for quorum sensing. Further evidence came from showing phase synchronization was density-dependent.

The present study described the types and amount of problems and services sought among returned deployed Army National Guard soldiers (4568 soldiers in 50 units). The study responds to gaps in the research literature to better understand community intervention needs of reservists. About half (48%) of the soldiers reported one or two problems, mostly those of psychological well-being, such as feelings of anger and frustration, upsetting memories, and troubled sleep (34% of the study sample), followed by problems of social support (18%), alcohol use (17%), feelings of isolation including suicidal thoughts (13%), and financial difficulties (11%). Having engaged in direct combat and having wounded or killed someone showed positive relationships with reported problems. One-third (35%) of soldiers who reported having used services went to one service and, generally, soldiers went to services related to their expressed problems. Variance in self-reported problems explained by service use was low, suggesting unsought postdeployment services.

Educational research has identified effective schools in terms of characteristics associated with high student achievement, and conversely, schools lacking these characteristics are often conceived as ineffective schools. In this article, I propose that organizational stress responses create the conditions that make schools effective or ineffective. In other words, low achievement does not make schools ineffective but rather organizational behavior associated with stress creates and perpetuates school ineffectiveness, including low achievement. Drawing on the threat-rigidity thesis and open systems theory, hypotheses regarding how groups and organizations respond to stress were tested using demographic and achievement data for students attending elementary schools, in addition to survey data obtained from students (N= 18,189), principals (N= 75), and parents (N= 13,768). Using cluster analysis, schools were grouped and described in terms of the school’s stress level (student populations requiring more resources for learning), school adaptations to stress (emphases on varied school internal processes), and school output (student achievement). To lessen input from the external environment, schools experiencing more stress had less permeable bound- aries, as indicated by parent reports of less school involvement and less positive school climate. Schools experiencing more stress also had more internal disruption, as indicated by less consensus among parents and students regarding school internal processes and by more principal changes. However, in such schools, there was little evidence of more control over school internal processes in terms of principals’ self-reported behavior and student and parent perceptions of school order and discipline, and teacher support of learning. Results call for a better understanding of school ineffectiveness in terms of organizational adaptations to stress and points at which to intervene for more effective school adaptation and functioning.

Organizational psychology has identified four recurrent organizational models (rational goal, open systems, human relations, and internal processes), each placing different emphases on internal and external organizational processes. Using a sample of 122 elementary schools in a large suburban school district located outside a metropolitan area, the present study examined the relation of school emphases on internal and external processes to school effectiveness and efficiency. Consistent with hypotheses, inefficient schools (lower-than-average student achievement test scores, adjusted by the percentage of students enrolled in the free and reduced-price meal program and per-pupil expenditures) were identified by the human relations model or as inward-directed with emphasis on the quality of student-school staff interpersonal relationships, by higher levels of student enjoyment, and by smaller student enrollments and smaller student-faculty ratios. Contrary to expectation, results showed that effective schools (higher-than-average student achievement test scores) were best described in terms of the rational goal model or as outward-directed, with emphasis on involving and empowering parents and on internal structure, control, and inflexibility (i.e., more school order and discipline). Results are discussed in terms of the broader organizational literature, specifically, competing organizational value orientations, effects of organizational structure and member characteristics on organizational process orientation, and the use of organizational process orientation as means to achieve organizational effectiveness and efficiency.

The present study employed a sample of 25,087 students enrolled in 117 elementary schools to test whether student perceptions obtained in a general survey of school learning and social environment conformed to the dimensions of Stockard and Mayberry's (1992) conceptual framework for school climate, and whether data could be summarized as grouped (school) or non-grouped (individual) data. A confirmatory factor analysis showed that the proposed framework adequately fits student perceptions of school climate. Hierarchical linear modeling (HLM) analyses showed between-school differences. Although school membership accounted for a small amount of variance in school climate measures, school climate means showed relatively high reliability. School climate dimensions most immediate to the student (Action-Instrumental support and Action-Expressive support) showed the strongest relations to both student self-reported academic performance and student satisfaction, and these relations were generally the same across the schools. As predicted, expressive support as opposed to instrumental support was more beneficial (in terms of self-reported academic performance) to students in schools having proportionally more socioeconomically disadvantaged students. Implications of results for educational research and educational practice regarding school climate are discussed.

Accumulating evidence from studies investigating the role naturally-occurring emotional support networks play in remediating psychological distress strongly suggests that such networks buffer personal distress and lessen the need for formal mental health care. Research findings also suggest that reliance on emotional support networks varies across ethnic groups. The present study compared emotional support network characteristics of Anglo-Americans to those of Mexican Americans, in addition to examining the relationship between the reliance on specific support providers and psychopathological symptoms for Anglo- and Mexican Americans. Randomly selected adult Anglo- and Mexican Americans (n = 515) living in one of three suburban communities in Southern California provided responses to a standardized measure of psychological impairment and named those persons on whom they depended in time of personal problems. Both Anglo- and English speaking Mexican American (ES MA) respondents reported significantly larger networks and more cumulative contact and reciprocity with network members than did Spanish-speaking Mexican Americans (SS MA) respondents. Anglos and ES MAs named significantly more friends and neighbors as emotional support providers than did SS MAs. SS MAs, on the other hand, more often depended on extended kin and spouses than did the other two subgroups. Professional caregivers accounted for a very small proportion of responses across the subgroups. The number of friends and neighbors as support providers was significantly and positively correlated with problems of social relations in only the SS MA subgroup. Implications of results for community mental health direct and indirect service components are discussed.

Discussions of Mexican American mental health need have been limited to analyses of service utilization statistics, most of which have shown Mexican Americans to use mental health services proportionally less than other racial/ethnic groups. Consequently, Mexican Americans have been viewed as a group having greater unmet mental health needs. Yet, these utilization-based needs assessments make an implicit and untested assumption: that the proportion of the psychologically impaired is comparable across racial/ethnic groups. The purpose of the present investigation was, first, to contribute to a baseline measurement of psychological impairment among Mexican Americans in order to assess what utilization should be for this group and, second, to determine relationships between impairment symptomatology and sociodemographic characteristics which are unique to the Mexican American population. Anglo- and Mexican Americans (n = 515) living in one of three suburban communities in Southern California were selected by way of a random-digit, multistage cluster telephone sampling procedure. Respondents gave responses to a standardized measurement of psychological impairment. Results showed that Anglo- and Mexican Americans did not differ in anxiety, psychosocial dysfunction, and depressive symptoms. Mexican Americans in the three communities, however, were found to use mental health services proportionally less than Anglos. Relationships between age and psychosocial dysfunction symptoms, and between income and anxiety problems were different for Mexican Americans than those for Anglos. Issues related to what constitutes mental health need and the use of self-report measures of impairment to estimate mental health need across culturally diverse groups are discussed.