60 resultados para hierarchical (multilevel) analysis


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Objective:The most difficult thyroid tumors to be diagnosed by cytology and histology are conventional follicular carcinomas (cFTCs) and oncocytic follicular carcinomas (oFTCs). Several microRNAs (miRNAs) have been previously found to be consistently deregulated in papillary thyroid carcinomas; however, very limited information is available for cFTC and oFTC. The aim of this study was to explore miRNA deregulation and find candidate miRNA markers for follicular carcinomas that can be used diagnostically.Design:Thirty-eight follicular thyroid carcinomas (21 cFTCs, 17 oFTCs) and 10 normal thyroid tissue samples were studied for expression of 381 miRNAs using human microarray assays. Expression of deregulated miRNAs was confirmed by individual RT-PCR assays in all samples. In addition, 11 follicular adenomas, two hyperplastic nodules (HNs), and 19 fine-needle aspiration samples were studied for expression of novel miRNA markers detected in this study.Results:The unsupervised hierarchical clustering analysis demonstrated individual clusters for cFTC and oFTC, indicating the difference in miRNA expression between these tumor types. Both cFTCs and oFTCs showed an up-regulation of miR-182/-183/-221/-222/-125a-3p and a down-regulation of miR-542-5p/-574-3p/-455/-199a. Novel miRNA (miR-885-5p) was found to be strongly up-regulated (>40-fold) in oFTCs but not in cFTCs, follicular adenomas, and HNs. The classification and regression tree algorithm applied to fine-needle aspiration samples demonstrated that three dysregulated miRNAs (miR-885-5p/-221/-574-3p) allowed distinguishing follicular thyroid carcinomas from benign HNs with high accuracy.Conclusions:In this study we demonstrate that different histopathological types of follicular thyroid carcinomas have distinct miRNA expression profiles. MiR-885-5p is highly up-regulated in oncocytic follicular carcinomas and may serve as a diagnostic marker for these tumors. A small set of deregulated miRNAs allows for an accurate discrimination between follicular carcinomas and hyperplastic nodules and can be used diagnostically in fine-needle aspiration biopsies.

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Microarray gene expression profiles of fresh clinical samples of chronic myeloid leukaemia in chronic phase, acute promyelocytic leukaemia and acute monocytic leukaemia were compared with profiles from cell lines representing the corresponding types of leukaemia (K562, NB4, HL60). In a hierarchical clustering analysis, all clinical samples clustered separately from the cell lines, regardless of leukaemic subtype. Gene ontology analysis showed that cell lines chiefly overexpressed genes related to macromolecular metabolism, whereas in clinical samples genes related to the immune response were abundantly expressed. These findings must be taken into consideration when conclusions from cell line-based studies are extrapolated to patients.

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The Nursing Home Survey on Patient Safety Culture (NHSPSC) was specifically developed for nursing homes to assess a facility’s safety climate and it consists of 12 dimensions. After its pilot testing, however, no fur- ther psychometric analyses were performed on the instrument. For this study of safety climate in Swiss nursing home units, the NHSPSC was linguistically adapted to the Swiss context and to address the unit as well as facility level, with the aim of testing aspects of the validity and reliability of the Swiss version before its use in Swiss nursing home units. Psychometric analyses were performed on data from 367 nurs- ing personnel from nine nursing homes in the German-speaking part of Switzerland (response rate = 66%), and content validity (CVI) examined. The statistical influence of unit membership on respondents’ answers, and on their agreement concerning their units’ safety climate, was tested using intraclass corre- lation coefficients (ICCs) and the rWG(J) interrater agreement index. A multilevel exploratory factor analysis (MEFA) with oblimin rotation was applied to examine the questionnaire’s dimensionality. Cronbach’s alpha and Raykov’s rho were calculated to assess factor reliability. The relationship of safety climate dimensions with clinical outcomes was explored. Expert feedback confirmed the relevance of the instru- ment’s items (CVI = 0.93). Personnel showed strong agreement in their perceptions in three dimensions of the questionnaire. ICCs supported a multilevel analysis. MEFA produced nine factors at the within-level (in comparison to 12 in the original version) and two factors at the between-level with satisfactory fit statis- tics. Raykov’s Rho for the single level factors ranged between 0.67 and 0.86. Some safety climate dimen- sions show moderate, but non-significant correlations with the use of bedrails, physical restraint use, and fall-related injuries. The Swiss version of the NHSPSC needs further refinement and testing before its use can be recommended in Swiss nursing homes: its dimensionality needs further clarification, particularly to distinguish items addressing the unit-level safety climate from those at the facility level.

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Background: The health action process approach (hapa) is a well-established model in predicting health behavior and assumes that volitional processes are important for effective behavioral change. however, only few studies have so far tested associations on the intraindividual level. thus, this study examined the inter- and intraindividual associations between volitional predictors and daily smoking around a quit attempt. method: overall, 105 smokers completed daily electronic questionnaires 10 days before and 21 days after a self-set quit date, including measures of intentions, self-efficacy, planning, action control and numbers of cigarettes smoked. multilevel analysis was applied. findings: at the interindividual level, higher mean levels of volitional predictors across the 32 days were associated with less numbers of cigarettes smoked. negative associations emerged also at the intraindividual level, indicating that on days with higher intentions, self-efficacy, planning and action control than usual, less cigarettes were smoked. moreover, these effects were stronger after the quit date than before the quit date. intentions and action control emerged as most powerful predictors at the intraindividual level. discussion: findings confirm assumptions of the hapa and emphasize the importance of volitional processes at the inter- and intraindividual level in the context of quitting smoking.

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BACKGROUND Follicular variant of papillary thyroid carcinoma (FVPTC) shares features of papillary (PTC) and follicular (FTC) thyroid carcinomas on a clinical, morphological, and genetic level. MicroRNA (miRNA) deregulation was extensively studied in PTCs and FTCs. However, very limited information is available for FVPTC. The aim of this study was to assess miRNA expression in FVPTC with the most comprehensive miRNA array panel and to correlate it with the clinicopathological data. METHODS Forty-four papillary thyroid carcinomas (17 FVPTC, 27 classic PTC) and eight normal thyroid tissue samples were analyzed for expression of 748 miRNAs using Human Microarray Assays on the ABI 7900 platform (Life Technologies, Carlsbad, CA). In addition, an independent set of 61 tumor and normal samples was studied for expression of novel miRNA markers detected in this study. RESULTS Overall, the miRNA expression profile demonstrated similar trends between FVPTC and classic PTC. Fourteen miRNAs were deregulated in FVPTC with a fold change of more than five (up/down), including miRNAs known to be upregulated in PTC (miR-146b-3p, -146-5p, -221, -222 and miR-222-5p) and novel miRNAs (miR-375, -551b, 181-2-3p, 99b-3p). However, the levels of miRNA expression were different between these tumor types and some miRNAs were uniquely dysregulated in FVPTC allowing separation of these tumors on the unsupervised hierarchical clustering analysis. Upregulation of novel miR-375 was confirmed in a large independent set of follicular cell derived neoplasms and benign nodules and demonstrated specific upregulation for PTC. Two miRNAs (miR-181a-2-3p, miR-99b-3p) were associated with an adverse outcome in FVPTC patients by a Kaplan-Meier (p < 0.05) and multivariate Cox regression analysis (p < 0.05). CONCLUSIONS Despite high similarity in miRNA expression between FVPTC and classic PTC, several miRNAs were uniquely expressed in each tumor type, supporting their histopathologic differences. Highly upregulated miRNA identified in this study (miR-375) can serve as a novel marker of papillary thyroid carcinoma, and miR-181a-2-3p and miR-99b-3p can predict relapse-free survival in patients with FVPTC thus potentially providing important diagnostic and predictive value.

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BACKGROUND The human waking EEG spectrum shows high heritability and stability and, despite maturational cortical changes, high test-retest reliability in children and teens. These phenomena have also been shown to be region specific. We examined the stability of the morphology of the wake EEG spectrum in children aged 11 to 13 years recorded over weekly intervals and assessed whether the waking EEG spectrum in children may also be trait-like. Three minutes of eyes open and three minutes of eyes closed waking EEG was recorded in 22 healthy children once a week for three consecutive weeks. Eyes open and closed EEG power density spectra were calculated for two central (C3LM and C4LM) and two occipital (O1LM and O2LM) derivations. A hierarchical cluster analysis was performed to determine whether the morphology of the waking EEG spectrum between 1 and 20 Hz is trait-like. We also examined the stability of the alpha peak using an ANOVA. RESULTS The morphology of the EEG spectrum recorded from central derivations was highly stable and unique to an individual (correctly classified in 85% of participants), while the EEG recorded from occipital derivations, while stable, was much less unique across individuals (correctly classified in 42% of participants). Furthermore, our analysis revealed an increase in alpha peak height concurrent with a decline in the frequency of the alpha peak across weeks for occipital derivations. No changes in either measure were observed in the central derivations. CONCLUSIONS Our results indicate that across weekly recordings, power spectra at central derivations exhibit more "trait-like" characteristics than occipital derivations. These results may be relevant for future studies searching for links between phenotypes, such as psychiatric diagnoses, and the underlying genes (i.e., endophenotypes) by suggesting that such studies should make use of more anterior rather than posterior EEG derivations.

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Female gender and low income are two markers for groups that have been historically disadvantaged within most societies. The study explores two research questions related to their political representation: (1) ‘Are parties biased towards the ideological preferences of male and rich citizens?’; and (2) ‘Does the proportionality of the electoral system moderate the degree of under-representation of women and poor citizens in the party system?’ A multilevel analysis of survey data from 24 parliamentary democracies indicates that there is some bias against those with low income and, at a much smaller rate, women. This has systemic consequences for the quality of representation, as the preferences of the complementary groups differ. The proportionality of the electoral system influences the degree of under-representation: specifically, larger district magnitudes help in closing the considerable gap between rich and poor.

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Recent research shows that well-educated citizens are more supportive of minority rights in direct democratic votes than people with less education. This article however suggests that educational effects on minority rights only emerge under certain conditions. A Bayesian multilevel analysis of 39 referendums and initiatives on minority rights in Switzerland (1981–2009) shows that educational effects are particularly strong when the rights of lesser-known cultural minorities are to be extended. They are entirely absent, however, when referenda address the curtailment of rights for well-known minority groups.

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Introduction: Over the last decades, Swiss sports clubs have lost their "monopoly" in the market for sports-related services and increasingly are in competition with other sports providers. For many sport clubs long-term membership cannot be seen as a matter of course. Current research on sports clubs in Switzerland – as well as for other European countries – confirms the increasing difficulties in achieving long-term member commitment. Looking at recent findings of the Swiss sport clubs report (Lamprecht, Fischer & Stamm, 2012), it can be noted, that a decrease in memberships does not equally affect all clubs. There are sports clubs – because of their specific situational and structural conditions – that have few problems with member fluctuation, while other clubs show considerable declines in membership. Therefore, a clear understanding of individual and structural factors that trigger and sustain member commitment would help sports clubs to tackle this problem more effectively. This situation poses the question: What are the individual and structural determinants that influence the tendency to continue or to quit the membership? Methods: Existing research has extensively investigated the drivers of members’ commitment at an individual level. As commitment of members usually occurs within an organizational context, the characteristics of the organisation should be also considered. However, this context has been largely neglected in current research. This presentation addresses both the individual characteristics of members and the corresponding structural conditions of sports clubs resulting in a multi-level framework for the investigation of the factors of members’ commitment in sports clubs. The multilevel analysis grant a adequate handling of hierarchically structured data (e.g., Hox, 2002). The influences of both the individual and context level on the stability of memberships are estimated in multi-level models based on a sample of n = 1,434 sport club members from 36 sports clubs. Results: Results of these multi-level analyses indicate that commitment of members is not just an outcome of individual characteristics, such as strong identification with the club, positively perceived communication and cooperation, satisfaction with sports clubs’ offers, or voluntary engagement. It is also influenced by club-specific structural conditions: stable memberships are more probable in rural sports clubs, and in clubs that explicitly support sociability, whereas sporting-success oriented goals in clubs have a destabilizing effect. Discussion/Conclusion: The proposed multi-level framework and the multi-level analysis can open new perspectives for research concerning commitment of members to sports clubs and other topics and problems of sport organisation research, especially in assisting to understand individual behavior within organizational contexts. References: Hox, J. J. (2002). Multilevel analysis: Techniques and applications. Mahwah: Lawrence Erlbaum. Lamprecht, M., Fischer, A., & Stamm, H.-P. (2012). Die Schweizer Sportvereine – Strukturen, Leistungen, Herausforderungen. Zurich: Seismo.

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Einleitung Folgt man den aktuellen Sportentwicklungsberichten, dann sehen sich zunehmend mehr Sportvereine mit Mitgliederfluktuationen sowie stagnierenden bzw. zurückgehenden Mitglie- derzahlen konfrontiert (Lamprecht et al. 2012). Jedoch werden nicht alle Vereine in gleichem Maße mit instabilen Mitgliedschaftsverhältnissen konfrontiert. So gibt es mit Blick auf die Mitgliederstruktur Vereine, die – aufgrund ihrer spezifischen situativen und strukturellen Bedingungen – kaum Probleme mit Mitgliederfluktuation und Vereinsaustritten haben, wohin- gegen andere Vereine mitunter erhebliche Mitgliederrückgänge verzeichnen. Demnach ist zu vermuten, dass sich das soziale Handeln der Vereinsmitglieder je nach Organisationsprofil der Vereine unterscheidet. Zwar werden Verknüpfungen von Individual- und korrespondierenden Strukturdaten innerhalb der Sportvereinsforschung bereits seit geraumer Zeit gefordert (z.B. Nagel, 2007), aber bis heute nicht konsequent umgesetzt. Es stellt sich deshalb die Frage, welche organisations- und individuumsbezogenen Faktoren für die Mitgliederbindung in Sportvereinen eine Rolle spielen? Theoretisch-methodisches Vorgehen Im Zusammenhang mit der Frage der Mitgliederbindung wird davon ausgegangen, dass kontextuelle Bedingungen individuelle Entscheidungen strukturieren und somit persönliche Handlungsketten beeinflussen können (Coleman, 1990). Auf dieser Grundlage wird ein Mehr- ebenenmodell entwickelt, das neben individuellen Merkmalen auch die Strukturbedingungen von Sportvereinen berücksichtigt, die im Zusammenhang mit der individuellen Wahlhandlung zwischen stabiler Mitgliedschaft oder Austritt stehen. Der organisationale Kontext Sportverein wird dabei als Interessenorganisation konzeptualisiert, der mit seinen Kontexteigenschaften als Gelegenheits- und Opportunitätsstruktur, als kultureller sowie sozialer Bezugsrahmen gewisse Anreize schafft („Logik der Situation“), die gemäss individueller Präferenzen („Logik der Selektion“) zu Parametern des Mitgliederhandelns werden können. Die aus dem Modell abgeleiteten Annahmen werden auf der Grundlage einer Mitglieder- befragung (n = 1.434) in 36 Schweizer Sportvereinen empirisch geprüft. Die adäquate Methode, welche die hierarchische Datenstruktur (jede Messung auf der Individualebene kann eindeutig einer Messung auf der Vereinsebene zugeordnet werden) adäquat berücksichtigt und folglich das entwickelte theoretische Modell statistisch umsetzt, ist die Mehrebenenanalyse (z.B. Hox, 2002). Entsprechend wird der Einfluss der Individual- und Kontextebene auf die Mitglieder- bindung in Sportvereinen anhand unterschiedlicher Mehrebenenmodelle (Random Intercept, Random Slope sowie Cross-Level Interaktionen) geschätzt. Ergebnisse Die Analysen machen deutlich, dass sich die dauerhafte Mitgliedschaft in Sportvereinen nicht allein auf individuelle Merkmale der Mitgliedschaft, wie eine ausgeprägte Verbundenheit, ein positiv wahrgenommenes soziales Miteinander, die Zufriedenheit mit der Vereinsarbeit sowie die ehrenamtliche Mitarbeit zurückführen lässt. Darüber hinaus nehmen auch vereinsspezi-fische Strukturbedingungen Einfluss auf die Mitgliederbindung, wobei in ländlich geprägten Sportvereinen und in Vereinen, die Geselligkeit explizit fordern und in denen das Vereinsziel sportlicher Erfolg eher eine untergeordnete Rolle spielt, die Austrittswahrscheinlichkeit geringer ist. Diskussion Die Befunde machen deutlich, dass für eine dauerhafte Mitgliedschaft sowohl zweckorientierte Nutzenüberlegungen als auch solidargemeinschaftliche Handlungsorientierungen eine zentrale Rolle spielen, so dass eine ausschließliche Dienstleistungs- bzw. Kundenorientierung als Strategie der Mitgliederbindung in Sportvereinen, wie sie vielfach (auch von Verbänden) nahegelegt wird, zu kurz greifen dürfte. Weiterhin zeigt sich, dass der Sportverein als Ort der Geselligkeit nicht nur Werte des sozialen Miteinanders und solidarischen Verhaltens vermittelt, sondern auch als Katalysator der Stabilität der Mitgliedschaft wirkt, sofern entsprechende Gelegenheiten zur Verfügung stehen. Im Zusammenhang mit der Mitgliederbindung scheint damit gerade jene vereinskulturelle Orientierung von Vereinen bedeutsam, die im Zuge der Modernisierung von Vereinsangeboten gern als überholt erachtet wird. Literatur Coleman, J. S. (1990). Foundations of social theory. Cambridge, MA: Belknap. Hox, J. (2002). Multilevel analysis. Techniques and applications. Mahwah: Erlbaum. Lamprecht, M., Fischer, A. & Stamm, H.-P. (2012). Die Schweizer Sportvereine – Strukturen, Leistungen, Herausforderungen. Zürich: Seismo. Nagel, S. (2007). Akteurtheoretische Analyse der Sportvereinsentwicklung – ein theoretisch- methodischer Bezugsrahmen. Sportwissenschaft, 37, 186–201.

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This article addresses factors that infl uence member commitment in sport clubs. Based on the theory of social action and the economic behaviour theory, it focuses not only on individual characteristics of club members but also on the corresponding structural conditions of sport clubs. Accordingly, a multilevel framework is developed for explaining member commitment in sport clubs. Different multilevel models were estimated in order to analyse the infl uences of both the individual and corresponding context Level in a sample of n = 1,699 members of 42 Swiss and German sport clubs. The multilevel analysis permitted an adequate handling of hierarchically structured data. Results of These multilevel analyses indicated that the commitment of members is not just an outcome of individual characteristics such as strong identifi cation with their club, positively perceived (collective) solidarity, satisfaction with their sport club, or voluntary engagement. It is also determined by club-specific structural conditions: commitment proves to be more probable in rural sport clubs and clubs that explicitly support sociability. Furthermore, cross-level effects in relation to member commitment were also found between the context variable sociability and the individual variable identification.

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Quantitative studies of the conditions and consequences of religious diversity are based mostly on indices that measure the variety of religious membership in a particular region. However, this line of research has become stagnant, and the question of whether diversity affects religious vitality remains unanswered. This article attempts to shed new light on the discussion by measuring religious diversity differently and capturing religious vitality independently of membership figures. In particular, it contrasts the Herfindahl-Hirschman Index based on membership proportions with a second measure of diversity: an index of organizational diversity. Conversely, the dependent variable religious vitality is measured not by using rates of participation in religious organizations but via the Centrality of Religion Scale. Based on ecological and individual level data of forty-three local regions in Finland, Germany, and Slovenia and using multilevel analysis, our results suggest that religious diversity is related to religious vitality. However, the nature of this association differs across subgroups.

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The present study explores teacher emotions, in particular how they are predicted by students’ behaviour and the interpersonal aspect of the teacher-student relationship (TSR). One hundred thirty-two secondary teachers participated in a quantitative study relying on self-report questionnaire data. Based on the model of teacher emotions by Frenzel (2014), teachers rated their experienced joy, anger and anxiety during classroom instruction (dependent variable). Students’ motivational behaviour (= engagement), socio-emotional behaviour (= discipline in class) and relational behaviour (= closeness; interpersonal TSR) were assessed as the independent variables. Teachers’ self-efficacy beliefs served as a control variable. Hierarchical regression analysis revealed that the interpersonal relationship formed between teachers and students was the strongest predictor for teachers’ joy (positive relation) and anxiety (negative relation), whereas lack of discipline in class best predicted teachers’ anger experiences. Students’ engagement also proved a significant predictor of teacher emotions. The results suggest that interpersonal TSR plays a particularly important role in teachers’ emotional experiences in class.

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BACKGROUND Cam-type femoroacetabular impingement (FAI) resulting from an abnormal nonspherical femoral head shape leads to chondrolabral damage and is considered a cause of early osteoarthritis. A previously developed experimental ovine FAI model induces a cam-type impingement that results in localized chondrolabral damage, replicating the patterns found in the human hip. Biochemical MRI modalities such as T2 and T2* may allow for evaluation of the cartilage biochemistry long before cartilage loss occurs and, for that reason, may be a worthwhile avenue of inquiry. QUESTIONS/PURPOSES We asked: (1) Does the histological grading of degenerated cartilage correlate with T2 or T2* values in this ovine FAI model? (2) How accurately can zones of degenerated cartilage be predicted with T2 or T2* MRI in this model? METHODS A cam-type FAI was induced in eight Swiss alpine sheep by performing a closing wedge intertrochanteric varus osteotomy. After ambulation of 10 to 14 weeks, the sheep were euthanized and a 3-T MRI of the hip was performed. T2 and T2* values were measured at six locations on the acetabulum and compared with the histological damage pattern using the Mankin score. This is an established histological scoring system to quantify cartilage degeneration. Both T2 and T2* values are determined by cartilage water content and its collagen fiber network. Of those, the T2* mapping is a more modern sequence with technical advantages (eg, shorter acquisition time). Correlation of the Mankin score and the T2 and T2* values, respectively, was evaluated using the Spearman's rank correlation coefficient. We used a hierarchical cluster analysis to calculate the positive and negative predictive values of T2 and T2* to predict advanced cartilage degeneration (Mankin ≥ 3). RESULTS We found a negative correlation between the Mankin score and both the T2 (p < 0.001, r = -0.79) and T2* values (p < 0.001, r = -0.90). For the T2 MRI technique, we found a positive predictive value of 100% (95% confidence interval [CI], 79%-100%) and a negative predictive value of 84% (95% CI, 67%-95%). For the T2* technique, we found a positive predictive value of 100% (95% CI, 79%-100%) and a negative predictive value of 94% (95% CI, 79%-99%). CONCLUSIONS T2 and T2* MRI modalities can reliably detect early cartilage degeneration in the experimental ovine FAI model. CLINICAL RELEVANCE T2 and T2* MRI modalities have the potential to allow for monitoring the natural course of osteoarthrosis noninvasively and to evaluate the results of surgical treatments targeted to joint preservation.