23 results on '"Krueger A"'
Search Results
2. Qualitative Evaluation from a Utilization Focused Perspective: The Minnesota Experience.
- Author
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Mueller, Marsha R. and Krueger, Richard A.
- Abstract
Two evaluation projects conducted for the Minnesota Agricultural Extension Service are examined from a user-focused perspective: (1) a needs assessment of large scale commercial farmers for program development by the Office of Special Programs; and (2) a review of the extension programs in Nicollet County. Each incorporated the focus group method as part of the project design. The studies are different in scope, design and the extent to which user-focused evaluation principles were considered. The first study used focus group interviews following a large scale quantitative survey in a county region of the state. The second study was designed to look at one county and the focus group procedure was the major information gathering technique. The "Personal Factor" continues to appear to be a most critical factor in utilization. When stakeholders need and want information for a specific purpose, the chances of future use are greatly enhanced. Limited county level studies may tend to result in greater immediate utilization than do the state wide or regional studies due to the more situationally specific nature and the fact that a particular environment is targeted. Investments of time and resources tend to correlate with utilization. The use of qualitative procedures appears to depend on situational factors. (PN)
- Published
- 1985
3. Pharmacy-based interdisciplinary intervention for patients with chronic heart failure: results of the PHARM-CHF randomized controlled trial.
- Author
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Schulz, Martin, Griese‐Mammen, Nina, Anker, Stefan D., Koehler, Friedrich, Ihle, Peter, Ruckes, Christian, Schumacher, Pia M., Trenk, Dietmar, Böhm, Michael, Laufs, Ulrich, Botermann, Lea, Krueger, Katrin, Krügerke, Nicole, Mantzke, Judith, Parrau, Natalie, Strauch, Dorothea, Wachter, Angelika, Fikenzer, Kati, Schubert, Ingrid, and Kloft, Charlotte
- Subjects
VENTRICULAR ejection fraction ,HEART failure patients - Abstract
Aims: Medication non-adherence is frequent and is associated with high morbidity and mortality in patients with chronic heart failure (CHF). We investigated whether an interdisciplinary intervention improves adherence in elderly CHF patients.Methods and Results: The study population (mean age 74 years, 62% male, mean left ventricular ejection fraction 47%, 52% in New York Heart Association class III) consisted of 110 patients randomized into the pharmacy care and 127 into the usual care group. The median follow-up was 2.0 years (interquartile range 1.2-2.7). The pharmacy care group received a medication review followed by regular dose dispensing and counselling. Control patients received usual care. The primary endpoint was medication adherence as proportion of days covered (PDC) within 365 days for three classes of heart failure medications (beta-blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and mineralocorticoid receptor antagonists). The main secondary outcome was the proportion of adherent patients (PDC ≥ 80%). The primary safety endpoint was days lost due to unplanned cardiovascular hospitalizations (blindly adjudicated) or death. Pharmacy care compared with usual care resulted in an absolute increase in mean adherence to three heart failure medications for 365 days [adjusted difference 5.7%, 95% confidence interval (CI) 1.6-9.8, P = 0.007]. The proportion of patients classified as adherent increased (odds ratio 2.9, 95% CI 1.4-5.9, P = 0.005). Pharmacy care improved quality of life after 2 years (adjusted difference in Minnesota Living with Heart Failure Questionnaire scores -7.8 points (-14.5 to -1.1; P = 0.02), compared to usual care. Pharmacy care did not affect the safety endpoints of hospitalizations or deaths.Conclusion: Pharmacy care safely improved adherence to heart failure medications and quality of life. [ABSTRACT FROM AUTHOR]- Published
- 2019
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4. Are Alcohol Trajectories a Useful Way of Identifying At-Risk Youth? A Multiwave Longitudinal-Epidemiologic Study.
- Author
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Vachon, David D., Krueger, Robert F., Irons, Daniel E., Iacono, William G., and McGue, Matt
- Subjects
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ALCOHOLISM , *EPIDEMIOLOGICAL research , *PATHOLOGICAL psychology , *HERITABILITY , *YOUTH & alcohol , *PSYCHIATRIC diagnosis , *ALCOHOL-induced disorders , *COMPARATIVE studies , *LONGITUDINAL method , *NEUROPSYCHOLOGICAL tests , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *RESEARCH funding , *TWINS , *EVALUATION research , *PREVENTION - Abstract
Objective: Trajectory approaches are a popular way of identifying subgroups of children and adolescents at high risk for developing alcohol use problems. However, mounting evidence challenges the meaning and utility of these putatively discrete alcohol trajectories, which can be analytically derived even in the absence of real subgroups. This study tests the hypothesis that alcohol trajectories may not reflect discrete groups-that the development of alcohol use is continuous rather than categorical.Method: A multiwave longitudinal-epidemiologic twin study was conducted using 3,762 twins (1,808 male and 1,954 female) aged 11 to 29 years from the Minnesota Center for Twin and Family Research (MCTFR). The main outcome measures included various assessments of substance use, psychopathology, personality, and cognitive ability.Results: Although multiple trajectories are derived from growth mixture modeling techniques, these trajectories are arrayed in a tiered spectrum of severity, from lower levels of use to higher levels of use. Trajectories show perfect rank-order stability throughout development, monotonic increases in heritability, and perfect rank-order correlations with established correlates of alcohol use, including other substance use behaviors, psychiatric disorders, personality traits, intelligence, and achievement.Conclusion: Alcohol trajectories may represent continuous gradations rather than qualitatively distinct subgroups. If so, early detection and interventions for youth based on trajectory subtyping will be less useful than continuous liability assessments. Furthermore, a continuous account of development counters the notion that individuals are predestined to follow one of a few categorically distinct pathways and promotes the opposite idea-that development is mutable, and its continuous terrain can be traversed in many directions. [ABSTRACT FROM AUTHOR]- Published
- 2017
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5. Environmental contributions to adolescent delinquency: a fresh look at the shared environment.
- Author
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Burt, S., McGue, Matt, Krueger, Robert, Iacono, William, Burt, S Alexandra, Krueger, Robert F, and Iacono, William G
- Subjects
JUVENILE offenders ,TEENAGERS ,JUVENILE delinquency ,SIBLINGS ,FAMILIES ,BEHAVIOR ,JUVENILE delinquency & psychology ,ADOPTION ,COMPARATIVE studies ,GENETICS ,LONGITUDINAL method ,RESEARCH methodology ,MEDICAL cooperation ,MULTIVARIATE analysis ,PARENT-child relationships ,PROBABILITY theory ,MATHEMATICAL models of psychology ,RESEARCH ,PHENOTYPES ,EVALUATION research ,SOCIAL context ,PSYCHOLOGY - Abstract
Few genetically-informative studies have attempted to explicitly identify the shared environmental (i.e., those environmental influences that contribute to sibling similarity) factors now known to contribute to adolescent delinquency. The current study therefore examined whether the parent-child relationship served as one source of these shared environmental influences. Participants were 610 adoptive and biological families from the Sibling Interaction and Behavior Study (SIBS). Parents and adolescents reported on their parent-child conflict and parental involvement with child, and adolescents reported on their own delinquent behaviors. We employed structural equation modeling and supplementary multilevel modeling, finding consistent evidence that the association between delinquency and the parent-child relationship is at least partially shared environmental in origin. Such findings provide an important extension of previous twin studies, as they suggest that passive genotype-environment correlations do not explain earlier findings of shared environmental influences on this association. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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6. Measurement invariance of DSM- IV alcohol, marijuana and cocaine dependence between community-sampled and clinically overselected studies.
- Author
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Derringer, Jaime, Krueger, Robert F., Dick, Danielle M., Agrawal, Arpana, Bucholz, Kathleen K., Foroud, Tatiana, Grucza, Richard A., Hesselbrock, Michie N., Hesselbrock, Victor, Kramer, John, Nurnberger, John I., Schuckit, Marc, Bierut, Laura J., Iacono, William G., and McGue, Matt
- Subjects
- *
CANNABIS (Genus) , *COCAINE , *DRUG addiction , *ETHANOL , *LONGITUDINAL method , *MATHEMATICAL models , *CLASSIFICATION of mental disorders , *PSYCHOMETRICS , *RESEARCH funding , *SEX distribution , *TWINS , *THEORY , *CASE-control method , *DATA analysis software , *DESCRIPTIVE statistics , *SYMPTOMS ,RESEARCH evaluation - Abstract
Aims To examine whether DSM- IV symptoms of substance dependence are psychometrically equivalent between existing community-sampled and clinically overselected studies. Participants A total of 2476 adult twins born in Minnesota and 4121 unrelated adult participants from a case-control study of alcohol dependence. Measurements Life-time DSM- IV alcohol, marijuana and cocaine dependence symptoms and ever use of each substance. Design We fitted a hierarchical model to the data, in which ever use and dependence symptoms for each substance were indicators of alcohol, marijuana or cocaine dependence which were, in turn, indicators of a multi-substance dependence factor. We then tested the model for measurement invariance across participant groups, defined by study source and participant sex. Findings The hierarchical model fitted well among males and females within each sample [comparative fit index ( CFI) > 0.96, Tucker- Lewis index ( TLI) > 0.95 and root mean square error of approximation ( RMSEA) < 0.04 for all], and a multi-group model demonstrated that model parameters were equivalent across sample- and sex-defined groups (Δ CFI = 0.002 between constrained and unconstrained models). Differences between groups in symptom endorsement rates could be expressed solely as mean differences in the multi-substance dependence factor. Conclusions Life-time substance dependence symptoms fitted a dimensional model well. Although clinically overselected participants endorsed more dependence symptoms, on average, than community-sampled participants, the pattern of symptom endorsement was similar across groups. From a measurement perspective, DSM- IV criteria are equally appropriate for describing substance dependence across different sampling methods. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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7. Delineating physiologic defensive reactivity in the domain of self-report: phenotypic and etiologic structure of dispositional fear.
- Author
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Kramer, M. D., Patrick, C. J., Krueger, R. F., and Gasperi, M.
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CHI-squared test ,STATISTICAL correlation ,FACTOR analysis ,FEAR ,PERSONALITY ,PATHOLOGICAL psychology ,QUESTIONNAIRES ,RESEARCH funding ,SELF-evaluation ,TWINS ,PHENOTYPES ,EFFECT sizes (Statistics) ,STRUCTURAL equation modeling ,DESCRIPTIVE statistics - Abstract
BackgroundIndividual differences in fear and fearlessness have been investigated at their extremes in relation to markedly different forms of psychopathology – anxiety disorders and psychopathy, respectively. A documented neural substrate of fear-related traits and disorders is defensive reactivity as reflected in aversive startle potentiation (ASP).MethodThe current study extended prior work by characterizing, in a sample of adult twins from the community (n=2511), the phenotypic and etiologic structure of self-report measures of fear and fearlessness known to be associated with ASP.ResultsAnalyses revealed a hierarchical structure to the trait fear domain, with an overarching, bipolar fear/fearlessness dimension saturating each measure in this domain, and subfactors labeled ‘distress,’ ‘stimulation seeking’ and ‘sociability’ accounting for additional variance in particular measures. The structure of genetic and non-shared environmental associations among the measures closely mirrored the phenotypic structure of the domain.ConclusionsThe findings have implications for proposals to reconceptualize psychopathology in neurobiological terms. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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8. Genetic and Environmental Contributions to the Association Between Anthropometric Measures and IQ: A Study of Minnesota Twins at Age 11 and 17.
- Author
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Silventoinen, Karri, Iacono, William, Krueger, Robert, and McGue, Matthew
- Subjects
GENOTYPE-environment interaction ,TWIN psychology ,COGNITION in children ,CHILD development ,ANTHROPOMETRY - Abstract
Associations of height and head circumference with IQ are well documented, but much less is known about the association of IQ with other anthropometric measures or the mechanisms behind these associations. We therefore analyzed the associations between IQ and several anthropometric measures using a twin-study design. Twins born in Minnesota were assessed at either age 11 (756 complete pairs) or 17 (626 complete pairs) and analyzed using genetic modeling. Head circumference and height showed the most consistent positive associations with IQ, whereas more detailed anthropometric measures were not significantly better predictors of IQ. These associations were mainly due to common genetic factors. Our results suggest that the same genetic factors have an effect on physical and cognitive development. Head circumference and height capture information on children's physical development, which is partly associated also with cognitive development. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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9. Soil Structure and Physical Properties under Rye-Corn Silage Double-Cropping Systems.
- Author
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Liesch, Amanda M., Krueger, Erik S., and Ochsner, Tyson E.
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SOIL structure , *SOIL physical chemistry , *CORN , *SILAGE , *TILLAGE , *COVER crops , *CROPPING systems , *ARABLE land - Abstract
Soils under continuous corn (Zea mays L) silage production are often subjected to heavy traffic and tillage, which can degrade soil structure and physical properties. Cover crops have been shown to benefit soil structure, but the effects of double-cropping on soil structure and physical properties are unknown. Our objective was to compare the soil structure and physical properties under rye (Secale cereale L.) and corn silage double-cropping with those under continuous corn silage in Minnesota during the 2007-2008 cropping year. A conventional tillage corn silage system served as the control. Double-crop treatments were conventional tillage winter rye harvested in May or June followed by no-till corn silage. Relative to the control, the double-cropping systems exhibited superior soil structure with up to 57% better visual soil structure scores and up to 16% smaller mean weight aggregate diameter. Visual soil structure scores exhibited seasonal dynamics with significant treatment effects in November and June but not in May when the structural assessment was conducted shortly after preplant tillage in the control. The double-cropping system increased the resilience of the soil to traffic. The saturated hydraulic conductivity in wheeltracked interrows was 375% higher in the double-cropping system relative to the control in July. Both the rye and the absence of tillage before com planting may have contributed to this improved resilience. Heavy traffic and tillage in continuous corn silage production systems can degrade soil structure and physical properties; however, the rye-corn silage double-cropping system provided a measure of protection. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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10. Genetic and environmental influences and covariance among meaning in life, religiousness, and spirituality.
- Author
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Steger, MichaelF., Hicks, BrianM., Krueger, RobertF., and Bouchard, ThomasJ.
- Subjects
ATTITUDE (Psychology) ,ANALYSIS of variance ,CHI-squared test ,CONFIDENCE intervals ,STATISTICAL correlation ,FACTOR analysis ,LIFE ,RELIGION ,RESEARCH evaluation ,RESEARCH funding ,STATISTICAL sampling ,SATISFACTION ,SPIRITUALITY ,STATISTICS ,TWINS ,EFFECT sizes (Statistics) ,MAXIMUM likelihood statistics ,DATA analysis software ,GENETICS - Abstract
Meaning in life, spirituality, and religiousness have been empirically linked in previous research. This study aimed to advance knowledge of the interrelations among these variables by examining their heritable and non-heritable sources of influence, as well as the genetic and environmental contributions to their inter-relations. A sample of 343 middle-aged twins drawn from the Minnesota Twin Registry completed measures of meaning in life and spirituality. There was evidence that religiousness, spirituality, and meaning in life shared common genetic and environmental influences, suggesting that these people's attitudes concerning these variables may arise from shared factors. These results provide novel evidence of a shared genetic substrate for meaning in life, religiousness, and spirituality, and support the possibility that people's basic attitudes about the meaning of existence are commonly rooted in evolved biological factors and conjointly influenced through people's experiences with life. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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11. Personality in Germany and Minnesota: An IRT-Based Comparison of MPQ Self-Reports.
- Author
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Johnson, Wendy, Spinath, Frank, Krueger, Robert F., Angleitner, Alois, and Riemann, Rainer
- Subjects
PERSONALITY & culture ,PERSONALITY questionnaires ,ITEM response theory ,PSYCHOLOGICAL tests ,AGGRESSION (Psychology) ,TRADITION (Philosophy) ,WELL-being - Abstract
We compared personality across cultures to explore the extent of cultural differences. This study used samples matched on gender and age from Germany and Minnesota to compare traditional scale scores and IRT-based parameters for Tellegen's (1982) Multidimensional Personality Questionnaire scales. Because the samples consisted of twins, we were able to replicate the findings from the subsamples consisting of one member of each pair with the subsamples consisting of their co-twins. When the full scales were considered, Germans were higher in Aggression and Absorption and Minnesotans were higher in Well-being, Control, and Traditionalism, but, except for those in Traditionalism, different item-difficulty parameters explained most of these differences. IRT highlighted less than optimal scale properties as well as differentially functioning items. We discuss the theoretical implications of these findings. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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12. Minnesota Center for Twin and Family Research.
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Iacono, William G., McGue, Matt, and Krueger, Robert F.
- Subjects
TWIN studies ,FAMILY research ,ADOPTION ,MENTAL health ,EPIDEMIOLOGICAL research ,FAMILIES ,GENETICS ,LONGITUDINAL method ,MENTAL illness ,RESEARCH funding ,ACQUISITION of data - Abstract
The Minnesota Center for Twin and Family Research (MCTFR) houses a collection of longitudinal, community-based twin-family and adoptee-family projects that focus on the mental health outcomes of adolescent youth with a special focus on the development of substance use and related behavior disorders. The Minnesota Twin Family Study includes epidemiological investigations of 11- and 17-year-old twins, an examination of 11-year-old twins selected for being at high risk for having a childhood disruptive behavior disorder, and a supplemental registry of young adult twins age 18 years and older who are not enrolled in these longitudinal studies. Also, part of the MCTFR is the Sibling Interaction and Behavior Study, a complementary prospective investigation of adolescent sibling pairs in families with adoptive and biological offspring. MCTFR participants from these various projects are assessed in person and through multiple informants to provide comprehensive coverage of psychological adjustment, mental health, and psychosocial risk/protective factors. Measurement of EEG and autonomic nervous system reactivity is also part of the assessment battery for twin families. This article provides an overview of study design and includes a review of recent MCTFR findings. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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13. The extended genotype: the heritability of personality accounts for the heritability of recalled family environments in twins reared apart.
- Author
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Krueger, Robert F., Markon, Kristian E., Bouchard, Thomas J., and Bouchard, Thomas J Jr
- Subjects
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PERSONALITY tests , *HEREDITY , *AGE groups , *GENETIC research , *CAMP sites - Abstract
How are retrospective accounts of family rearing environments linked to adult personality? We addressed this question by measuring both domains in a sample of 180 reared-apart twins. Twins completed extensive measures of rearing environments (the Minnesota-Briggs History Record, the Block Environmental Questionnaire, the Family Environment Scale, and the Physical Facilities Questionnaire) and an omnibus measure of adult personality (the Multidimensional Personality Questionnaire). Retrospective accounts of family environments were partially heritable and all the heritable variance in environmental measures could be accounted for by heritable variance in personality. In addition, differences between twins in their accounts of their rearing environments (nonshared environmental factors) were not significantly linked to differences between twins in their personalities. Hence, family environmental measures appear to be heritable because personality genes influence the way people shape and recall their rearing environments. In addition, differences in reared-apart twins' retrospectively recalled rearing environments appear to have little impact on differences in their personalities in adulthood. [ABSTRACT FROM AUTHOR]
- Published
- 2003
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14. Normal and abnormal personality traits: evidence for genetic and environmental relationships in the Minnesota Study of Twins Reared Apart.
- Author
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Markon, Kristian E., Krueger, Robert F., Bouchard, Thomas J., Gottesman, Irving I., and Bouchard, Thomas J Jr
- Subjects
- *
PERSONALITY , *TWIN psychology , *MINNESOTA Multiphasic Personality Inventory , *PSYCHOLOGY , *NATURE & nurture , *GENETICS - Abstract
Recent studies have demonstrated substantial correlations between normal and abnormal personality traits. Yet little is known about how these correlations are mediated genetically and environmentally: Do normal and abnormal personality traits stem from the same underlying genes and environments? We addressed this question using data from 128 monozygotic and dizygotic twin pairs in the Minnesota Study of Twins Reared Apart (MISTRA). Additive genetic and nonshared environmental correlations between scales of the Minnesota Multiphasic Personality Inventory (MMPI)--an index of abnormal personality--and the Multidimensional Personality Questionnaire (MPQ)--an index of normal personality--were estimated. Results indicated that phenotypic correlations between normal and abnormal personality were mediated by genetic as well as environmental factors, although the magnitude of genetic mediation tended to be larger overall. Moreover, the patterns of phenotypic, genetic, and environmental relationships among the scales were similar, suggesting that influences on normal and abnormal personality act through systems common to both. It is suggested that future research focus on the neurogenetic substrates of these shared systems and how dysfunction in these systems influences development of disordered personality. [ABSTRACT FROM AUTHOR]
- Published
- 2002
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15. Sources of covariation among attention-deficit/hyperactivity disorder, oppositional defiant disorder, and conduct disorder: the importance of shared environment.
- Author
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Burt, S. Alexandra, Krueger, Robert F., McGue, Matt, and Iacono, William G.
- Subjects
- *
MENTAL illness risk factors , *DISEASE risk factors - Abstract
Research has documented high levels of covariation among childhood externalizing disorders, but the etiology of this covariation is unclear. To unravel the sources of covariation among attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD), the authors studied 11-year-old twins (N = 1,506) from the Minnesota Twin Family Study. Symptom counts for each of these disorders were obtained from interviews administered to the twins and their mothers. A model was fit that allowed the parsing of genetic, shared environmental (factors that make family members similar to each other), and nonshared environmental (factors that make family members different from each other) contributions to covariation. The results revealed that although each disorder was influenced by genetic and environmental factors, a single shared environmental factor made the largest contribution to the covariation among ADHD, ODD, and CD. [ABSTRACT FROM AUTHOR]
- Published
- 2001
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16. Challenges of Small-Town Lawyering.
- Author
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KRUEGER, JOSEPH
- Subjects
CIVIL law ,ESTATE planning ,MUNICIPAL ordinances - Abstract
An interview with Joseph Krueger, District Representative of the Minnesota State Bar Association (MSBA) Assembly is presented. He talks about his specialization areas in the practice of law which include civil litigation, estate planning and municipal law in Minnesota. He discusses his experience of practicing in small firm and being a member of the MSBA. He mentions that attorneys outside Minnesota are his greatest resource.
- Published
- 2015
17. MNOSHA update.
- Author
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Krueger, Jim
- Subjects
FIRE departments ,LEGAL compliance - Abstract
The article reports that the Minnesota Occupational Safety and Health Administration (MNOSHA) has conducted 61 compliance inspections at fire departments between 2007 and 2011.
- Published
- 2012
18. Annual production of macroinvertebrates in three streams of different water quality
- Author
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Waters, Thomas F. and Krueger, Charles C.
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ECOLOGY ,HYDROGEN-ion concentration ,RIVERS ,BIOTIC communities - Published
- 1983
19. WILL THE TWINS TAKE BACK THE CENTRAL?
- Author
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Krueger, Myrna
- Subjects
MARKETING ,PERFORMANCE ,AGRICULTURAL marketing - Abstract
The article speculates on the Colle and McVoy twin's favorable return on the agri-marketing business. Myrna Krueger, Colle+McVoy National Careers Committee Chair, believes that the Minnesota twins have a good chance to take back the central this year, taking into consideration their performances during the off-season.
- Published
- 2006
20. Influence of provenance and transport process on the geochemistry and radiogenic (Hf, Nd, and Sr) isotopic composition of Pleistocene glacial sediments, Minnesota, USA.
- Author
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Wittkop, Chad, Bartley, Julie K., Krueger, Russell, Bouvier, Audrey, Georg, R. Bastian, Knaeble, Alan R., St. Clair, Katherine, Piper, Christian, and Breckenridge, Andy
- Subjects
- *
GEOCHEMISTRY , *SEDIMENTARY rocks , *STRONTIUM , *CRYSTALLINE rocks , *HEAVY minerals , *SEDIMENT transport , *SEDIMENTS , *TRACE elements - Abstract
We develop a broad geochemical dataset from 50 samples of Pleistocene glacial till matrix (including three lacustrine samples) representing four sediment provenances collected from across Minnesota, USA. Such a dataset is useful both in the context of regional studies of glaciation, and in efforts to understand how provenance and glacial processes impact the geochemistry of sediment archives. The principal sediment sources of the four provenances include materials from the Archean-Proterozoic Canadian Shield, the Proterozoic Midcontinent Rift, Paleozoic carbonates, and Cenozoic and Mesozoic clastic sediments. We measured major element geochemistry in all till samples in both <2 mm and <63 μm size fractions, the trace element geochemistry in most samples, radiogenic isotopic compositions (Sr, Nd) in 13 representative samples, and Hf-isotope composition in 6 samples. Differences in source rock composition explain the primary variations in the geochemistry of our samples. In untreated (carbonate-bearing) samples, Na 2 O + K 2 O versus Fe 2 O 3 or CaO are distinct in tills sourced from crystalline rocks versus sedimentary basins, and mechanical mixing from different source areas is evident on 100-km glacial transport length scales. Glacial materials originating from sedimentary rocks have higher chemical index of alteration (CIA) relative to materials sourced from the predominately igneous and metamorphic Canadian Shield. Increased values of Rb + Sr, Zr/Sc, and Cr + Ni are also associated with tills derived from crystalline rocks relative to tills derived from sedimentary rocks. Both the Hf- and Nd-isotopic composition of glacial sediments distinguish crystalline rock sources (less radiogenic) versus sedimentary rock sources (more radiogenic). The Sr-, and, to a lesser degree, the Hf-isotopic composition of lacustrine samples is influenced by subtle changes in sample mineral composition, reflecting both source rock variability and the sorting of clay and heavy mineral components during sediment transport. A carbonate-free composite of our till samples was found to be broadly representative of a Canadian Shield source. The ability to discern provenance and sediment transport process controls on glacial sediment geochemistry presents an opportunity to extend our understanding of past ice-sheet dynamics, and validates approaches that use tills as a proxy for continental crustal composition, provided that the influences of sediment recycling are carefully considered. • Continental glacial till matrix geochemistry retain signatures of source rocks >400 km up ice. • Provenance exerts a primary influence on the chemical index of alteration (CIA) of tills. • Sample Zr/Sc and Hf-isotope composition identifies lacustrine deposition. • Glacial till Sr-isotope composition is influenced by source rock weathering. • Multiproxy geochemical analysis identifies tills generated from crystalline versus sedimentary rock sources. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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21. Julia Brown.
- Author
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KRUEGER, WALTER
- Subjects
- *
CONCERTS , *ORGAN music - Abstract
The article reviews a concert by organist Julia Brown at Maternity of Mary catholic Church in Saint Paul, Minnesota, in June 2008.
- Published
- 2008
22. Stephen Tharp.
- Author
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KRUEGER, WALTER
- Subjects
- *
CONCERTS , *ORGAN music - Abstract
The article reviews a concert by organist Stephen Tharp at Saint Olaf Roman Catholic Church in Minneapolis, Minnesota, in June 2008.
- Published
- 2008
23. Gender differences and developmental change in externalizing disorders from late adolescence to early adulthood: A longitudinal twin study.
- Author
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Hicks, Brian M., Blonigen, Daniel M., Kramer, Mark D., Krueger, Robert F., Patrick, Christopher J., Lacono, William G., McGue, Matt, and Iacono, William G
- Subjects
- *
ALCOHOLISM , *NICOTINE addiction , *DRUG addiction , *ANTISOCIAL personality disorders , *DEVELOPMENTAL biology , *TWINS ,SEX differences (Biology) - Abstract
Using data from over 1,000 male and female twins participating in the Minnesota Twin Family Study, the authors examined developmental change, gender differences, and genetic and environmental contributions to the symptom levels of four externalizing disorders (adult antisocial behavior, alcohol dependence, nicotine dependence, and drug dependence) from ages 17 to 24. Both men and women increased in symptoms for each externalizing disorder, with men increasing at a greater rate than women, such that a modest gender gap at age 17 widened to a large one at age 24. Additionally, a mean-level gender difference on a latent Externalizing factor could account for the mean-level gender differences for the individual disorders. Biometric analyses revealed increasing genetic variation and heritability for men but a trend toward decreasing genetic variation and increasing environmental effects for women. Results illustrate the importance of gender and developmental context for symptom expression and the utility of structural models to integrate general trends and disorder-specific characteristics. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
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