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PubMed2004

Neighborhood predictors of concealed firearm carrying among children and adolescents: results from the project on human development in Chicago neighborhoods.

BACKGROUND: Previous studies of concealed firearm carrying among children and adolescents have focused on individual risk factors. OBJECTIVE: To identify features of neighborhoods associated with concealed firearm carrying among a representative sample of youth from Chicago, Ill. DESIGN: Cross-sectional analysis of individual- and neighborhood-level data collected by the Project on Human Development in Chicago Neighborhoods. SETTING: Families and neighborhoods in Chicago. PARTICIPANTS: Population-based sample of 1842 multiethnic youth aged 9 to 19 years and the 218 neighborhoods in which they resided. Main Outcome Measure Whether youth had ever carried a concealed firearm. RESULTS: Lifetime estimates for concealed firearm carrying were 4.9% for males and 1.1% for females. We found that youth in safer and less disordered neighborhoods were less likely than youth in unsafe and more disordered neighborhoods to carry concealed firearms. Specifically, multilevel nonlinear regression models identified a positive association between concealed firearm carrying and (1) community members' ratings of neighborhoods as unsafe for children; (2) neighborhood social disorder; and (3) neighborhood physical disorder. Neighborhood collective efficacy was negatively associated with concealed firearm carrying. Models controlled for neighborhood economic indicators and individual and family factors associated with the carrying of concealed firearms by youth. CONCLUSIONS: Youth are less likely to carry concealed firearms in areas where there is less violence and increased safety. Interventions to improve neighborhood conditions such as increasing safety, improving collective efficacy, and reducing social and physical disorder may be efficacious in preventing firearm use and its associated injuries and death among youth.

Adolescent↗
PubMed1999

From fold predictions to function predictions: automation of functional site conservation analysis for functional genome predictions.

A database of functional sites for proteins with known structures, SITE, is constructed and used in conjunction with a simple pattern matching program SiteMatch to evaluate possible function conservation in a recently constructed database of fold predictions for Escherichia coli proteins (Rychlewski L et al., 1999, Protein Sci 8:614-624). In this and other prediction databases, fold predictions are based on algorithms that can recognize weak sequence similarities and putatively assign new proteins into already characterized protein families. It is not clear whether such sequence similarities arise from distant homologies or general similarity of physicochemical features along the sequence. Leaving aside the important question of nature of relations within fold superfamilies, it is possible to assess possible function conservation by looking at the pattern of conservation of crucial functional residues. SITE consists of a multilevel function description based on structure annotations and structure analyses. In particular, active site residues, ligand binding residues, and patterns of hydrophobic residues on the protein surface are used to describe different functional features. SiteMatch, a simple pattern matching program, is designed to check the conservation of residues involved in protein activity in alignments generated by any alignment method. Here, this procedure is used to study conservation of functional features in alignments between protein sequences from the E. coli genome and their optimal structural templates. The optimal templates were identified and alignments taken from the database of genomic structural predictions was described in a previous publication (Rychlewski L et al., 1999, Protein Sci 8:614-624). An automated assessment of function conservation is used to analyze the relation between fold and function similarity for a large number of fold predictions. For instance, it is shown that identifying low significance predictions with a high level of functional residue conservations can be used to extend the prediction sensitivity for fold prediction methods. Over 100 new fold/function predictions in this class were obtained in the E. coli genome. At the same time, about 30% of our previous fold predictions are not confirmed as function predictions, further highlighting the problem of function divergence in fold superfamilies.

Algorithms↗
PubMed2006

For whom is income inequality most harmful? A multi-level analysis of income inequality and mortality in Norway.

This study investigates the degree to which contextual income inequality in economic regions in Norway affected mortality during the 1990s, above the effects of mean regional income and individual-level confounders. A further objective is to explore whether income inequality effects on mortality differed between socioeconomic groups. Data were constructed by linkages of administrative registers encompassing all Norwegian inhabitants. The outcome variable was all-cause mortality during 6 years (i.e., died 1994-1999 or alive end of 1999). Men and women aged 25-66 in 1993 were analysed. Regions' mean income and income inequality (in terms of gini coefficients) were calculated from consumption-units-adjusted family disposable income. Individual-level variables included sex, age, marital status, individual income, education, and being a recipient of health-related welfare benefits. Multilevel logistic regression models were fitted for 2,197,231 individuals nested within 88 regions. After adjusting for regional mean income and individual-level variables, the odds ratio (OR) for mortality 1994-1999 was 1.028 (95% CI 1.023-1.033) on the gini variable multiplied by 100. Analyses of cross-level interactions indicated some, albeit modest, income inequality effects on mortality in the upper income and educational categories. Among those with low individual income, low education, and among recipients of health-related welfare benefits, mortality effects of higher regional income inequality were significantly stronger than among those more advantageously placed in the social structure. The results of this study differ from previous studies which have suggested that contextual income inequality has a minor impact on population health in egalitarian countries. The results indicate that in Norway, neither a comparatively egalitarian income distribution nor generous and comprehensive welfare institutions hindered the emergence of regional-level income inequality effects on mortality, and these effects were particularly marked among socioeconomically disadvantaged groups. Explanations for the results are discussed.

Adult↗
PubMed2002

Cervical spine injuries in patients 65 years old and older: epidemiologic analysis regarding the effects of age and injury mechanism on distribution, type, and stability of injuries.

OBJECTIVE: Our objective was to describe types and distribution of cervical spine injuries in elderly patients in regard to causative trauma mechanism and patient age. MATERIALS AND METHODS: The distribution and type of 225 cervical spine injuries in 149 consecutive patients 65 years old and older over a 5-year interval were retrospectively assessed. For each patient, initial admission imaging studies were reviewed, and injuries were classified. Trauma mechanism (falls from standing or seated height vs higher energy mechanisms) and initial clinical and neurologic status were recorded. Data were correlated according to patients' age (65-75 years and >75 years) and causative trauma mechanism. RESULTS: Ninety-five (64%) of 149 patients had upper cervical spine injuries. Fifty-nine (40%) of 149 patients had multilevel injuries. Main causes for cervical spine injuries were motor vehicle crashes in "young elderly" (65-75 years old; 36/59, 61%) and falls from standing or seated height in "old elderly" (>75 years old; 36/90, 40%). Fracture patterns at risk for neurologic deterioration were common (>50%), even in the absence of acute myelopathy or radiculopathy. Patients older than 75 years, independent of causative mechanism, and patients who fell from standing height, independent of age, were more likely to have injuries of the upper cervical spine (p = 0.026 and p = 0.006, respectively). CONCLUSION: Cervical spine injuries in elderly patients tend to involve more than one level with consistent clinical instability and commonly occur at the atlantoaxial complex. Old elderly patients and patients who fall from standing height are more prone to injuries of the upper cervical spine.

Accidental Falls↗
PubMed2005

Multilevel IRT using dichotomous and polytomous response data.

A structural multilevel model is presented where some of the variables cannot be observed directly but are measured using tests or questionnaires. Observed dichotomous or ordinal polytomous response data serve to measure the latent variables using an item response theory model. The latent variables can be defined at any level of the multilevel model. A Bayesian procedure Markov chain Monte Carlo (MCMC), to estimate all parameters simultaneously is presented. It is shown that certain model checks and model comparisons can be done using the MCMC output. The techniques are illustrated using a simulation study and an application involving students' achievements on a mathematics test and test results regarding management characteristics of teachers and principles.

Analysis of Variance↗
PubMed1990

Simultaneous combined anterior and posterior fusion. An independent analysis of a treatment for the disabled low-back pain patient.

Sixty-nine patients were treated by a simultaneous combined anterior and posterior fusion for disabling low-back pain as directed by discographic pain provocation. They were evaluated independently, with an average follow-up of 2 1/2 years (range, 1.6 to 4.1 years). Fusion rates in excess of 90% were noted in patients who had undergone one- and two-level fusions, whereas the fusion rate for three-level procedures dropped to 77.8%. Acceptable clinical results were seen in approximately 80% of the primary low-back pain and the postlaminectomy patients. Results within the group of patients who had undergone previous fusion procedures were less favorable: two thirds good or fair. The available evidence suggests that this procedure is a valid surgical technique, especially applicable to multilevel lumbar fusions and the postlaminectomy patient. Despite its seemingly radical nature, it can be performed quickly and safely with adequate surgical training.

Adult↗
PubMedDate not supplied

Heterarchy of cognition: the depths and the highs of a framework for memory research.

To celebrate the levels-of-processing approach, I describe a multilevel evolutionary architecture for human behaviour and cognition. New experimental data on human eye movements are presented that demonstrate a possibility of splitting visual perceptual activity at least on two hierarchical but closely interrelated levels of processing. Furthermore, data from behavioural studies of human memory and neuroimaging testify that within the domain of cognition proper two higher levels can be differentiated. I call them "conceptual structures" and "metacognitive coordinations" and provide evidence that the latter may residue in the phylogenetically new structures of prefrontal and particularly right prefrontal cortices. From this point of few, the most natural framework for an analysis of the levels-of-processing effects on human memory is to consider them as interactions within the main gradients of evolution and development of the corresponding neurophysiological mechanisms. Finally, several new, still unanswered questions for the future research are formulated.

Biological Evolution↗
PubMed1995

Identifiable risk factors for secondary neurologic deterioration in the cervical spine-injured patient.

STUDY DESIGN: This was a retrospective prevalence study. OBJECTIVE: A review of structural cervical spine injuries (fracture or dislocation) treated at a regional spine injury referral center from 1987 to 1992 was undertaken to identify and analyze patients who had secondary neurologic deterioration after they had arrived and had primary assessment in stable neurologic condition (intact or compromised, but not evolving). SUMMARY OF BACKGROUND DATA: Multiple case reports and cohort studies have suggested possible risk factors for late neurologic deterioration without probabilities analysis. METHODS: Information was obtained retrospectively from clinical records and radiographs. Three-hundred-twelve cases were reviewed. Thirty-one were excluded and 281 were analyzed. RESULTS: An index group of 15 patients (5%) had motor neurologic deterioration after primary assessment at the referral center. Control group "A" was composed of 70 patients (25%) who had a motor neurologic deficit on admission and did not deteriorate. Control group "B" was the balance of 196 patients (70%) with structural cervical injuries, but no neurologic compromise. Factors distinguishing the index group from control subjects included flexural mechanism of injury and chronic multilevel spinal arthritis with ankylosis. All secondary deteriorations occurred with the injury level caudad to the fourth cervical vertebra. Routine three-view cervical radiographs were relatively insensitive in detecting injury in the index group compared with the pooled control subjects. Patients' ability to comply with recommended treatment was not a factor in secondary deteriorations and there generally was no identifiable precipitant event before secondary deterioration. CONCLUSION: Cervical traumatized patients with flexural injury or chronic multilevel spinal arthritis with ankylosis are at increased risk of having secondary motor neurologic deterioration.

Adult↗
PubMed1996

Organizing Asian Pacific Islanders in an urban community to reduce HIV risk: a case study.

We present a case study of community organization efforts within the Asian Pacific Islander communities of San Diego County to reduce the risk of HIV transmission. We utilized a five-phase process to implement the strategies of locality development, social planning, and social action: community analysis, program design and initiation, program implementation, program maintenance and consolidation, and program reassessment. An evaluation of the process indicates that there were increases over time in the project's activities as well as in the levels of interagency connectedness. This is one of the few reported efforts to organize Asian Pacific Islander groups to address HIV transmission. Key elements that led to the successful organization of the original project into a tax-exempt nonprofit entity (the Asian Pacific Islander Community AIDS Project) were emphasis on community ownership, reliance on group consensus, use of "gatekeepers" to access communities, simultaneous multilevel programming, and service to the community as a "coordinating" entity.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Putting the individual back into individual growth curves.

Scaling of time (age) in latent growth curve (LGC) models has important implications for studies of development. When participants begin a study at different ages, sample means and covariance-based structural equation modeling (SEM) approaches produce biased estimates of the variance of the intercept and the covariance between the Intercept and Slope factors. However, individual data vector-based SEM approaches produce proper estimates of these parameters that are identical to those produced by multilevel modeling (MLM). Scaling of the time variable also raises issues regarding the interpretation of within- and between-persons effects of time that parallel those associated with centering of predictor variables in MLM. A numerical example is used to illustrate these issues, and an Mx script for fitting individual data vector-based LGC models is provided.

Adolescent↗
PubMed2002

Challenges to improving the impact of worksite cancer prevention programs: comparing reach, enrollment, and attrition using active versus passive recruitment strategies.

OBJECTIVE: The impact of worksite intervention studies is maximized when reach and enrollment are high and attrition is low. Differences in reach, enrollment, and retention were investigated by comparing 2 different employee recruitment methods for a home-based cancer-prevention intervention study. METHODS: Twenty-two worksites (N = 10,014 employees) chose either active or passive methods to recruit employees into a home-based intervention study. Reach (e.g., number of employees who gave permission to be called at home), Enrollment (e.g., number of employees who joined the home intervention study), and Attrition (e.g., number who did not complete the 12- and 24-month follow-ups) were determined. Analysis at the cluster level assessed differences between worksites that selected active (n = 12) versus passive (n = 10) recruitment methods on key outcomes of interest. Employees recruited by passive methods had significantly higher reach (74.5% vs. 24.4% for active) but significantly lower enrollment (41% vs. 78%) and retention (54% vs. 70%) rates (all ps < .0001). Passive methods also successfully enrolled a more diverse, high-risk employee sample. Passive (vs. active) recruitment methods hold advantages for increased reach and the ability to retain a more representative employee sample. Implications of these results for the design of future worksite studies that involve multilevel recruitment methods are discussed.

Adult↗
PubMed2005

Isotopic fractionation indicates anaerobic monochlorobenzene biodegradation.

The concentration and isotopic composition of monochlorobenzene (MCB) was monitored in the plume of an anaerobic, contaminated aquifer in Bitterfeld, Germany. An enrichment in the carbon isotopic composition of more than 4 delta units was found at the fringes of the plume relative to the center (-26.5 %), suggesting the occurrence of in situ biodegradation of MCB. A similar enrichment was measured in a detailed cross-section of the plume and in depth-specific samples obtained in a multilevel sampling well. The latter samples gave a good correlation of MCB concentrations and respective isotopic composition according to the Rayleigh equation. On the other hand, batch experiments using the aerobic MCB-degrading strains Ralstonia sp. DSM 8910, Acidovorax facilis UFZ B517, Rhodococcus erythropolis UFZ B528, and Pseudomonas veronii UFZ B547 showed that the known aerobic pathway initiated by dioxygenases does not result in a significant isotopic fractionation. Thus, a novel anaerobic pathway resulting in an isotopic fractionation appears to be the predominant process of MCB degradation in this aquifer. The study also clearly demonstrates the usefulness of isotopic fractionation analysis to prove biodegradation directly in the field, even when microcosm studies are not available and a metabolic pathway has not yet been elucidated.

Anaerobiosis↗
PubMedDate not supplied

[Radiculographic symptoms of changes in the adjacent intervertebral disks in the course of lumbar disk prolapse].

From a group of 400 radiculographic examinations the authors selected 34 cases operated upon for disc prolapse. These patients had additional signs of prolapse of the neighbouring intervertebral discs. The analysis showed that the latter signs were present mostly in the discs situated above the level of disc prolapse. In only two cases these changes were found in the disc situated below the level of prolapse. The sign of bulging-in dural sac in radiculography may be an impression of bulging disc and, much less frequently, it can be caused by a slight prolapse of the disc. Demonstration of these changes in contrast-medium investigations of the vertebral canal should be taken into account during the planned operation. The importance of disturbances of spinal biomechanics in the development of multilevel discopathy is stressed.

Humans↗
PubMed2000

Survivor guilt, submissive behaviour and evolutionary theory: the down-side of winning in social comparison.

In prior research submissive behaviour has been studied in relation to social comparison. Evolutionary theory conceptualized submissive behaviour as a fear-based self-protective strategy when in a subordinate position. In this study we hypothesized that survivor guilt, the type of guilt associated with feeling better off than others, is also linked to submissive behaviour. The Interpersonal Guilt Questionnaire, the Submissive Behaviour Inventory, the Eysenck Personality Questionnaire-Revised and the Automatic Thoughts Questionnaire were administered to a sample of 199 college students. Submissive behaviour was found to be significantly correlated with survivor guilt. Introversion, used as an indirect measure of the fear of being put down, was also correlated with submissive behaviour. A principal components analysis found two components: the first was composed of high loadings of submissiveness, survivor guilt and omnipotent responsibility guilt; the second was composed of high loadings of submissiveness and introversion. This supports the hypothesis that there may be two motivational states related to submissive behaviour, the fear of harm to the self, as described in prior studies, and the fear of harm to another or guilt-based submissive behaviour. We propose that survivor guilt has been selected by evolution as a psychological mechanism supporting group living, and that it may be considered from the perspective of inclusive fitness, reciprocal altruism, and multilevel selection theory.

Adaptation, Psychological↗
PubMed2003

Nanocapillary array interconnects for gated analyte injections and electrophoretic separations in multilayer microfluidic architectures.

An electrokinetic injection technique is described which uses a nuclear track-etched nanocapillary array to inject sample plugs from one layer of a microfluidic device into another vertically separated layer for electrophoretic separations. Gated injection protocols for analyte separations, reported here, establish nanocapillary array interconnects as a route to multilevel microfluidic analytical designs. The hybrid nanofluidic/microfluidic gated injection protocol allows sample preparation and separation to be implemented in separate horizontal planes, thereby achieving multilayer integration. Repeated injections and separations of FITC-labeled arginine and tryptophan, using 200-nm pore-diameter capillary array injectors in place of traditional cross injectors are used to demonstrate gated injection with a bias configuration that uses relay switching of a single high-voltage source. Injection times as rapid as 0.3 s along with separation reproducibilities as low as 1% for FITC-labeled arginine exemplify the capability for fast, serial separations and analyses. Impedance analysis of the micro-/nanofluidic network is used to gain further insight into the mechanism by which this actively controlled nanofluidic-interconnect injection method works. Gated sample introduction via a nanocapillary array interconnect allows the injection and separation protocols to be optimized independently, thus realizing the versatility needed for real-world implementation of rapid, serial microchip analyses.

Arginine↗
PubMed2002

A maize r1 gene is regulated post-transcriptionally by differential splicing of its leader.

Anthocyanin biosynthesis in Zea mays is controlled by regulatory genes of the r1/b1 family that encode bHLH transcription factors. Analysis of the 381 nucleotide leader sequence of a member of this family, Sn, discloses the presence of five ATG triplets upstream of the coding region and three upstream open reading frames (uORFs) of 38, 15 and 13 amino acids respectively. RT-PCR studies revealed that a splicing event occurs in the leader region in the different tissues tested. Splicing deletes 146 nucleotides which include uORF2 and uORF3. By trans-activation experiments in maize protoplasts we find that the spliced leader, compared to the non-spliced one, reduces the number of pigmented protoplasts by four-fold. We suggest a multilevel regulation of the Sn transcription factor acting not only at the transcriptional but also at the post-transcriptional level.

5' Untranslated Regions↗
PubMed2006

Family relational factors in pediatric depression and asthma: pathways of effect.

OBJECTIVE: This study tested a multilevel biobehavioral family model proposing that negative family emotional climate contributes to child depressive symptoms, which in turn contribute to asthma disease severity. Parent-child relational insecurity is proposed as a mediator. METHOD: Children with asthma (N = 112; ages 7-18; 55% male) reported relational security, anxiety, and depressive symptoms. Parent(s) reported demographics, asthma history and symptoms, and family emotional expression. Asthma diagnosis was confirmed by medical history provided by parent and child together, clinical evaluation, pulmonary function tests, and methacholine challenge, with disease severity categorized by National Heart, Lung, and Blood Institute guidelines. Medication adherence was measured prospectively. RESULTS: Path analysis indicated a good fit of data to the hypothesized model (chi2 = 0.072, p =.97, normal fit index = 0.998, root mean square error of approximation = 0.000). Negative family emotional climate predicted child depressive symptoms (beta =.21, p < .04), which predicted asthma disease severity (beta =.35, p < .001), with relational insecurity a partial mediator (beta = -.23, p < .05, beta =.46, p < .001, respectively). Depression was associated with disease severity even after controlling for adherence (r p = 0.38, p < .05). CONCLUSION: Findings are consistent with the proposed family model, suggesting the clinical importance of assessing and intervening in these specific family relational processes when treating children with depression and asthma.

Adolescent↗
PubMed1999

Abdominal injuries associated with lumbar spine fractures in blunt trauma.

BACKGROUND: Specific analysis of the relationship between abdominal injuries and lumbar spine fractures has not yet been reported. METHODS: A retrospective review of 258 blunt trauma patients with lumbar spine fractures treated between 1991 and 1996. RESULTS: 26 patients sustained concomitant lumbar spine fractures and abdominal injuries. The mechanism of injury was motor vehicle collision (73%), pedestrian-struck (11%), fall (8%) and assault (8%) resulting in ISS, RTS and mortality of 27 +/- 4, 6.5 +/- 0.4 and 8%, respectively. Forty-four lumbar spine fractures were identified (1.7/pt) in association with splenic (54%), renal (41%), hepatic (32%) and small bowel (23%) injuries and no retroperitoneal involvement. Multilevel lumbar spine fractures were associated with a higher organ injury/fracture ratio compared with single level fractures (p < 0.01) including a twofold higher incidence of solid organ (spleen, liver and kidney) injury (p < 0.01). The level and type of fracture did not affect the incidence of total and individual organ injury. Patients with abdominal injuries were more severely injured mainly due to increased incidence of associated thoracic injuries although no significant difference in mortality was observed. CONCLUSION: Abdominal injuries occurred only in the minority of blunt trauma patients with lumbar spine fractures. These injuries, which followed a similar distribution pattern as in blunt trauma in general, occurred most commonly due to motor vehicle collisions and in association with multilevel vertebral fractures. No correlation with fracture type or level was identified.

Abdominal Injuries↗