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PubMed2005

Residential instability in socioeconomically deprived neighbourhoods, good or bad?

Previously, both positive and negative effects of residential instability on various health outcomes have been described. The present study tests these effects in a European context, using two different data-sources (1) neighbourhood level data on socioeconomic deprivation and residential instability, and (2) individual-level community survey data to assess quality of life. Multilevel regression analyses showed that socioeconomic deprivation was negatively associated with several dimensions of quality of life, in stable neighbourhoods, while no such effect was observed in average or unstable neighbourhoods. Thus, when accounting for interaction effects, residential instability appeared to protect against negative effects of neighbourhood poverty and, therefore, may be beneficial for residents' quality of life.

Adult↗
PubMed2001

Proximate and contextual socioeconomic determinants of mortality: multilevel approaches in a setting with universal health care coverage.

Investigations of contextual factors (income inequality, cultural disruption, access to health and social services, safety and crime rate, and others) have received little emphasis by epidemiologists, although a few have demonstrated the importance of such factors for mortality, particularly in the United States. To expand current understanding of the importance of contextual factors, the authors evaluated mortality in a longitudinal study in Nova Scotia, Canada, where all residents have greater access to health and social services and where income inequalities are smaller than in the United States. A total of 2,116 participants were followed from 1990 through December 1999, linked to the 1991 Canada Census as a source of neighborhood characteristics, and analyzed using individual-level and multilevel logistic regression. Well-educated and high-earning persons fared better. Neighborhood socioeconomic characteristics (neighborhood income, educational level, unemployment rate), in contrast, were not significantly associated with mortality. However, within advantaged neighborhoods, the importance of individual income and education for mortality was increased relative to disadvantaged neighborhoods. The latter findings may direct health policy aimed at reducing health inequalities.

Adolescent↗
PubMed2005

Regularities and diversity in developmental pathways: mother-infant relationships in hamadryas baboons.

Change, stasis, stability, discontinuity, orderliness, and diversity are all potential characteristics of developmental systems. This study uses multilevel modeling to characterize the normative developmental pathways of the early social relationships of 23 mother-infant pairs embedded in a multilayered colony of hamadryas baboons (Papio hamadryas hamadryas). The relationships were assessed by means of 27 behavioral measures that were collected during 100-220 focal sampling sessions per infant, from birth to 380 days of age (25 two-week age intervals). Seventy four percent of the behavioral measures exhibited an age-related pattern. Infant age, however, was not predictive of the rate of the behaviors relating to the management of mother-infant conflicts. This study provides empirical evidence that the development of mother-infant relationships may involve periods of change and stasis, overall orderliness, and diversity as well as canalization of developmental pathways. We believe that growth curve analysis can be useful to tackle various hot issues in the study of behavioral development.

Animals↗
PubMed2005

Multilevel spinal growth modulation with an anterolateral flexible tether in an immature bovine model.

STUDY DESIGN: A bovine model was used to evaluate the effects of a multilevel anterolateral flexible tether in a growing spine. OBJECTIVE: To evaluate the radiographic changes in a growing spine with a multilevel anterolateral tether. SUMMARY OF BACKGROUND DATA: Spinal growth modulation has long been considered as a conceptually attractive and elegant possible alternative to arthrodesis in the treatment of idiopathic scoliosis. Although some experimental studies have described spinal growth modulation, few have described a purely mechanical tether. Clinical studies of spinal epiphysiodesis have described inconsistent curve stabilization and/or correction. METHODS: A total of 33 one-month-old male calves underwent a single thoracotomy and placement of vertebral screws at T6-T9. In 11 animals, one screw per level was connected by a 3/16 in. stainless steel cable (single tether). In 11 animals, two screws per level were connected by two cables (double tether). In the remaining 11 animals, single screws in each level were left unconnected (control). After 6 months, the spines were harvested and underwent radiographic analysis. RESULTS: In the control group, there was little change in the coronal and sagittal measurements during the survival period. In the single tether group, there was variable instrumentation fixation and inconsistent creation of coronal deformity, which ranged from 0 degrees to 31 degrees. The double-tether group had more consistent creation of deformity, ranging from 23 degrees to 57 degrees. CONCLUSIONS: Given adequate bony fixation, a flexible lateral spinal tether can affect growth modulation. This technique of growth modulation may serve as a future fusionless method of correction in a growing patient with scoliosis.

Animals↗
PubMed2005

Coping with interpersonal stress: role of big five traits.

Seventy-one couples living in a stepfamily context reported interpersonal family stressors and related coping strategies daily for 1 week in a daily process study. The role of personality and of the stressful context in each of the spouse's coping was examined. Personality was assessed via the Five-Factor Model (Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness). Two types of stressors emerged as primary dimensions of stepfamily stress: marital conflict and child misbehavior. These were treated as contextual factors in multilevel modeling analyses examining the independent and interactive effects of personality and situation on coping. Nine subscales of coping were examined based on three main functions of coping: problem-, emotion- and relationship-focused. Both the situational context and the five dimensions of personality examined were significantly and independently related to coping-strategy use. Moreover, there were significant personality-by-context interactions. The present study highlights the importance of considering personality in context when examining coping behaviors.

Adaptation, Psychological↗
PubMed2006

Tongue-base suspension in conjunction with uvulopalatopharyngoplasty for treatment of severe obstructive sleep apnea: long-term follow-up results.

OBJECTIVES/HYPOTHESIS: To evaluate the usefulness of tongue-base suspension (TBS) in addition to uvulopalatopharyngoplasty (UPPP) in the treatment of obstructive sleep apnea syndrome (OSAS). STUDY DESIGN: Long-term prospective case series. SETTING: University tertiary care medical center. METHODS: Fifty-five consecutive patients with severe OSAS (apnea-hypopnea index [AHI] 52.8+/-14.9 events/hr) with multilevel upper airway obstruction who refused treatment with continuous positive airway pressure underwent UPPP plus TBS with the Repose system. All patients were evaluated before surgery by clinical history, Epworth Sleepiness Scale (ESS), fiberoptic nasopharyngoscopy with Müller maneuver, and nocturnal polysomnography (PSG). After 3 years of surgery, all patients were re-evaluated at the clinic and had ESS test and full PSG. Surgical success was defined when the ESS dropped bellow 11, and the AHI decreased below the threshold of 20 events per hour of sleep and at least 50% from the preoperative value RESULTS: There were 42 (78%) patients in which the AHI score decreased more than 50%, the AHI was lower than 20 events/hr in the PSG, and the ESS was lower than 11 after 3-years of follow-up (surgical success index). Logistic regression analysis demonstrated that body mass index at baseline was the only variable with significant statistical power to predict surgical success (odds ratio 0.85; 0.73-0.95, 95% confidence interval, P<.01) CONCLUSION: When associated with UPPP, the TBS technique performed with the Repose system demonstrates a surgical success of up to 78% for patients with severe OSA who refused nasal continuous positive airway pressure.

Female↗
PubMed2004

Management practices and heifer characteristics associated with early lactation somatic cell count of Belgian dairy heifers.

Associations between somatic cell counts (SCC) from heifers between 5 and 14 d in milk (DIM) and both herd-management practices and heifer characteristics were studied for 1912 heifers in 159 dairy herds in Flanders (Belgium). In higher-producing herds and in herds with an average calving age of heifers > 27 mo, SCC of heifers was lower than in less-producing herds or in herds with an average calving age < or = 27 mo. Heifers raised in herds with a higher bulk-milk somatic cell count had higher SCC. In herds in which heifers calved on slatted floors, heifers had lower SCC compared with herds in which heifers calved on nonslatted floors. A significant difference in SCC was observed between provinces. At the heifer level, SCC decreased with increasing DIM. On average, heifers calving in April to June had higher SCC, compared with those calving in the other months of the year. In the multilevel regression models, nearly all the variations of SCC resided at the heifer level, indicating that preventive measures against udder health problems in freshening dairy heifers should, in the short term, focus more on factors that vary between heifers than on factors that vary between herds. However, for the long term, the need to identify new, and to implement known, herd-level strategies is important.

Animals↗
PubMed2000

Automatic classification of protein sequences into structure/function groups via parallel cascade identification: a feasibility study.

A recent paper introduced the approach of using nonlinear system identification as a means for automatically classifying protein sequences into their structure/function families. The particular technique utilized, known as parallel cascade identification (PCI), could train classifiers on a very limited set of exemplars from the protein families to be distinguished and still achieve impressively good two-way classifications. For the nonlinear system classifiers to have numerical inputs, each amino acid in the protein was mapped into a corresponding hydrophobicity value, and the resulting hydrophobicity profile was used in place of the primary amino acid sequence. While the ensuing classification accuracy was gratifying, the use of (Rose scale) hydrophobicity values had some disadvantages. These included representing multiple amino acids by the same value, weighting some amino acids more heavily than others, and covering a narrow numerical range, resulting in a poor input for system identification. This paper introduces binary and multilevel sequence codes to represent amino acids, for use in protein classification. The new binary and multilevel sequences, which are still able to encode information such as hydrophobicity, polarity, and charge, avoid the above disadvantages and increase classification accuracy. Indeed, over a much larger test set than in the original study, parallel cascade models using numerical profiles constructed with the new codes achieved slightly higher two-way classification rates than did hidden Markov models (HMMs) using the primary amino acid sequences, and combining PCI and HMM approaches increased accuracy.

Algorithms↗
PubMed1991

Expectations and high school change: teacher-researcher collaboration to prevent school failure.

Describes the multilevel outcomes of a collaborative preventive intervention for ninth-graders at risk for school failure using qualitative and quasi-experimental methods. Teachers, administrators, and researchers implemented innovative practices communicating positive expectations for low-achieving adolescents in their transition to high school. Changes were made in the practices of curriculum, grouping, evaluation, motivation, student responsibility, and relationships (in the classroom, with parents, and in the school). Both implementation and evaluation evolved as a function of collaboration. Change was promising but not uniform. Project teachers became more positive about students and colleagues, expanded their roles, and changed school tracking policies. The 158 project students, in contrast to the 154 comparison students showed improved grades and disciplinary referrals post-intervention and increased retention in school 1 year later, but their absences rose and improved performance was not maintained. The implications of this analysis for school-based interventions and its evaluation are discussed.

Adolescent↗
PubMedDate not supplied

Barriers to physical activity maintenance after cardiac rehabilitation.

PURPOSE: Little is known about the contextual determinants for the maintenance of physical activity after cardiac rehabilitation. This study aimed to examine perceived social, psychological, and health-related barriers to the maintenance of physical activity among phase 2 cardiac rehabilitation graduates. METHODS: Researchers using an open-ended format asked 160 participants (121 men and 39 women) 6 months after rehabilitation to identify perceived barriers to physical activity maintenance. The content of the participant responses was analyzed through categorization and coding of data, with independent review used to assess accuracy and reliability of decision rules. A social ecologic perspective was used for secondary coding and categorization. A chi analysis of categories was conducted to explore differences by gender, ethnicity, education, and employment. RESULTS: Four categories were developed from the coded responses: intrapersonal, interpersonal, environmental, and organizational. In their responses, 93% of the participants reported intrapersonal barriers, with 24% reporting interpersonal barriers, 18% reporting environmental barriers, and 11% reporting organizational barriers. Years of education contributed significantly to acceptance of an inactive lifestyle among those less educated (chi = 32.489; P = .028). Employment status showed significant differences for work as a barrier among those employed full-time (chi = 13.570, P = .004). Barriers to physical activity by gender showed significant differences for interpersonal barriers as a whole (chi = 6.804; P = .009). CONCLUSIONS: The open-ended format provided rich narrative data regarding barriers to the maintenance of physical activity. The acknowledgment of barriers, particularly from a social ecologic perspective, is needed to guide innovative, multilevel interventions for promoting physical activity maintenance among those with diagnosed coronary heart disease.

Adult↗
PubMed1994

Drug use, drug trafficking, and weapon carrying among low-income, African-American, early adolescent boys.

OBJECTIVE: To examine relationships involving three extremely high-risk behaviors (drug use, drug trafficking, and weapon carrying) among low-income, urban, African-American early adolescent boys using both quantitative and qualitative methods. METHOD: The quantitative phase included 192 African-American boys from 9 through 15 years of age recruited from recreation centers located in low-income communities. Youth completed a survey addressing personal risk practices; intentions to engage in risk practices; risk taking among family, friends and community; and values toward risk practices. They also completed standardized assessments of sensation seeking, perceived peer pressure, and parent-child communication. All questionnaires were self-administered through MacIntosh computers programmed to present questions aurally and visually. The qualitative phase included 12 African-American youth from low-income, urban families. The youth participated in 60- to 90-minute interviews regarding drug activities and violence. RESULTS: Most boys (73%) were not involved in either drug activities or weapon carrying. Boys who were involved in drug activities or weapon carrying were often involved in other high-risk activities (cigarette and alcohol use, school failure and expulsion) and had low rates of adaptive communication with their parents. The boys reported high rates of drug involvement by their family, friends, and community. However, psychological and interpersonal factors were better predictors of individual risk activities than community or family variables. Personal values regarding economics predicted drug trafficking. More than 56% of the boys who reported past involvement in drug activities did not anticipate future involvement. CONCLUSIONS: Multilevel strategies are necessary to prevent involvement in drug activities and weapon carrying. Intervention programs should begin early and should promote communication between parents and children, adaptive behavior in school, and avoidance of cigarette and alcohol use. Community-level interventions are needed to alter the myth that drug involvement and weapon carrying are normative and to promote images that are less materialistic and more supportive of education and future-oriented activities.

Adolescent↗
PubMed2002

Police and pastoral power: governmentality and correctional forensic psychiatric nursing.

Police and pastoral power: governmentality and correctional forensic psychiatric nursing Since 1978, the federal inmates of Canada have had access to a full range of psychiatric care within the penitentiary system. Several psychiatric units are now integrated into the correctional services of Canada. This paper presents the results of a grounded theory doctoral study undertaken in a multilevel secured psychiatric ward within the Canadian federal penitentiary system. The author describes and discusses the results of qualitative data that emerged from his fieldwork. The concept of governmentality, as defined by the late French philosopher Michel Foucault, constitutes one of the major theoretical tools that were helpful in analyzing these data. Police and pastoral power, two dimensions of the security apparatus of governmentality, were found to be useful in understanding and characterizing nursing practice caught between the penal and the psychiatric dispositifs. A Foucauldian perspective allows one to understand the manner in which forensic psychiatric nursing is involved in the governance of mentally ill inmates through three forms of power - sovereign, disciplinary and pastoral - which have posited nursing practice as a strategic tool of the correctional services. This research consists of a study of nursing practice in an extreme setting that deserves a radical analysis.

Canada↗
PubMed1990

Coexistence of cervical and lumbar disc disease.

A retrospective analysis of 200 patients requiring cervical disc surgery was performed to determine the frequency of coexistent lumbar disc or spine abnormalities. The duration of follow-up ranged from 5 to 25 years, averaging 14 years. Sixty percent were women and 40% were men, their ages ranging from 25-73 years. Antecedent motor vehicle injury had occurred in 49 cases and work injury to the spine in 23. Sixty-four percent had no history of prior back injury. It was found that over 31% had undergone lumbar disc surgery, and a high number of patients demonstrated abnormal lumbar radiographs or myelograms, including 78 with bulging discs, 100 with major root defects, 78 with minor root defects, 8 with spinal stenosis, and 7 with spondylolisthesis. Myelograms were normal in 22 cases. The sites of lumbar abnormalities included L4-5 (110), L5-S1 (90), and multilevel (8). There was a higher incidence of lumbar disc abnormalities associated with multilevel cervical spondylosis. There also was a relationship between residual symptoms and myelographic abnormalities. Two studies in the authors' institution suggest an autoimmune basis for the frequent coexistence of cervical and lumbar disc disease, namely the demonstration of antigenic properties in the nucleus pulposus and high serum immunoglobulins.

Adult↗
PubMed2006

A multi-level decomposition of variance in somatic symptom reporting in families with adolescent children.

OBJECTIVES: This paper examines four different levels of possible variation in symptom reporting: occasion, day, person and family. DESIGN: In order to rule out effects of retrospection, concurrent symptom reporting was assessed prospectively using a computer-assisted self-report method. METHODS: A decomposition of variance in symptom reporting was conducted using diary data from families with adolescent children. We used palmtop computers to assess concurrent somatic complaints from parents and children six times a day for seven consecutive days. In two separate studies, 314 and 254 participants from 96 and 77 families, respectively, participated. A generalized multilevel linear models approach was used to analyze the data. Symptom reports were modelled using a logistic response function, and random effects were allowed at the family, person and day level, with extra-binomial variation allowed for on the occasion level. RESULTS: Substantial variability was observed at the person, day and occasion level but not at the family level. CONCLUSIONS: To explain symptom reporting in normally healthy individuals, situational as well as person characteristics should be taken into account. Family characteristics, however, would not help to clarify symptom reporting in all family members.

Adolescent↗
PubMed1975

A theoretical and empirical approach to the study of development.

Developmental psychology, in spite of its dynamic growth, has not, thus far, generated a general theory of human development. Present developmental theories are either cognitive or ontogenetic, or both. All are descriptive. Their powers of explanation are limited. None of them include emotional development. It is argued that a theory of development in order to claim generality must (a) include emotional development, and (b) offer means of explaining, rather than only describing, developmental transformations. A nonontogenetic theory of development, called theory of positive disintegration, appears to fulfill these conditions. It is built on Jacksonian principles of evolution of levels of functioning. The central concept of the theory is that of multilevelness of developmental phenomena. Development is seen to be a function of the level of behavioral organization. The theory defines five levels. Each level constitutes a distinct structure. The dynamic elements of the structure of each level are identified. Positive disintegration is the name for the process by which the structure of a higher level replaces the structure of a lower one. The theory explains different developmental patterns by introducing the concept of developmental potential (DP). Although DP is a purely logical notion, it is given observable dimensions designated as dimensions of mental functioning. There are five of these and they correspond to psychomotor, sensual, imaginational, intellectual, and emotional modes of functioning. The first half of the monograph is devoted to the conceptual structure of the theory. The second half to empirical tests of the theory. Three such tests were made on data generated from an atomistic analysis of autobiographies. The first test consisted of the comparison of developmental cross-sections obtained from different sources of data (subjects) with the overall pattern of five levels of development. The different cross-sections overlap with each other and with different segments of the total theoretical pattern. Superimposed on each other they reconstitute the total pattern. The second test consisted of a comparison between computed and clinically derived values for DP for each subject in the study. The third test was a comparison of DP values obtained from early and late parts of an autobiography. An empirical equation for DP was used in the second and the third test. Parameters represented in the equation appear sufficient to account for individual differences in patterns and levels of development.

Behavior↗
PubMed2006

Density-functional geometry optimization of the 150,000-atom photosystem-I trimer.

We present a linear-scaling method based on the use of density-functional theory (DFT) for the system-wide optimization of x-ray structural coordinates and apply it to optimize the 150,000 atoms of the photosystem-I (PS-I) trimer. The method is based on repetitive applications of a multilevel ONIOM procedure using the PW916-31G(d) DFT calculations for the high level and PM3 for the lower level; this method treats all atoms in the structure equivalently, a structure in which the majority of the atoms can be considered as part of some internal "active site." To obtain a realistic single structure, some changes to the original protein model were necessary but these are kept to a minimum in order that the optimized structure most closely resembles the original x-ray one. Optimization has profound effects on the perceived electronic properties of the cofactors, with, e.g., optimization lowering the internal energy of the chlorophylls by on average 53 kcal mol(-1) and eliminates the enormous 115 kcal mol(-1) energy spread depicted by the original x-ray heavy-atom coordinates. A highly precise structure for PS-I results that is suitable for analysis of device function. Significant qualitative features of the structure are also improved such as correction of an error in the stereochemistry of one of the chlorophylls in the "special pair" of the reaction center, as well as the replacement of a water molecule with a metal cation in a critical region on the C3 axis. The method also reveals other unusual features of the structure, leading both to suggestions concerning device functionality and possible mutations between gene sequencing and x-ray structure determination. The optimization scheme is thus shown to augment the molecular modeling schemes that are currently used to add medium-resolution structural information to the raw scattering data in order to obtain atomically resolved structures. System-wide optimization is now a feasible process and its use within protein x-ray data refinement should be considered.

Binding Sites↗
PubMed1998

[Anxiety and hemodynamics: correlations in hypertensive patients].

AIM: Syndrome analysis of functional relationships between personality disorders, autonomic regulation and psychic performance in relation to hemodynamic condition of hypertensive patients. MATERIALS AND METHODS: MMP1, Tailor's anxiety scale, Burdon and Schulte tables, variation pulsometry, tetrapolar chest rheography were used in examination of 86 patients with stage I and II hypertension. RESULTS: In early hypertension, weak anxiety and subclinical emotional disturbances, dominant was a parasympathetic trend of the vegetative tone without central control of the cardiac rhythm in hyperkinetic circulation. Changes in cortical neurodynamics manifested with minor attenuation of the ability to focus attention. Progression of angiospasticity and anxiety gave rise to psychic maladjustment in the form of anxiety-depression disorders with autonomic dysfunction in hypokinetic circulation, overcentralization of cardiac rhythm control. This was associated with a decline in mental performance. CONCLUSION: Systemic investigations of the emotional sphere, central hemodynamics and autonomic regulation of cardiac rhythm enable assessment of multilevel structure and severity of psychocardiac syndrome in hypertensive patients which is important both for therapeutic and expert practice.

Anxiety↗
PubMed2004

Predictors of life satisfaction: perceptions of older community-dwelling adults.

The purpose of this study was to investigate variables that predict life satisfaction in elderly individuals. A convenience sample of 70 older community-dwelling adults participated in the study. Instruments used included the Life Satisfaction Index A Scale, three subscales from the Self-Evaluation of Life Function Scale, the Perceived Control Scale, Hollingshead's Two Factor Index of Social Position, and the Self-Rated Health Subscale of the Philadelphia Geriatric Center Multilevel Assessment Instrument. When the influence of health and social position was held constant, social interaction was the only additional significant predictor of life satisfaction. When health and social position were not held constant, social interaction, perceived control, and social position were significant predictors of life satisfaction. The findings indicate that nursing practice, education, and research should focus on assessment and interventions relative to promoting and maintaining health, perceived control, and social interaction among elderly individuals living in the community.

Aged↗