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PubMedDate not supplied

The importance of decisional balance and self-efficacy in relation to stages of change for fruit and vegetable intakes by young adults.

PURPOSE: To examine the stages of change, decisional balance, and self-efficacy constructs in relation to fruit and vegetable intakes by young adults 18-24 years old. DESIGN: A cross-sectional project was conducted by 10 states in January-July 2000 to examine decisional balance and self-efficacy in relation to stage of change for increasing fruit and vegetable intake among young adults. SUBJECTS: In all, 1545 usable surveys were returned (response rate = 55%). More non-respondents were men and precontemplators than respondents. Sixty-one percent of respondents were women, 90.3% were white, and 49.7% were current students. SETTING: Alabama, Kansas, Maine, Michigan, Nebraska, New York, Rhode Island, Oregon, South Dakota, and Wisconsin. MEASURES: A telephone screening interview and a self-administered mail survey. ANALYSIS: Analysis of variance, principal components analysis, cluster analysis, and chi 2 test. RESULTS: From precontemplation to maintenance, a significant linear trend was found toward higher food intake and self-efficacy for fruits and vegetables. The patterns of shifts in the pros and cons across the stages resembled those of other health behaviors. The decisional balance items were further classified into five component factors that varied significantly in importance across the stages. Four subject clusters were derived (unconcerned, reluctant, exploring, and action-oriented); distribution of the clusters agreed with that of the five stages. CONCLUSIONS: This study supports applicability of the Transtheoretical Model for assessing fruit and vegetable consumption by young adults. Derivation of the four clusters implies the importance of including decisional balance and self-efficacy as outcome measures besides dietary behavior for evaluating the effectiveness of nutrition interventions.

Adolescent↗

PubMedDate not supplied

[Forms of independence and the residential environment--an empirical contribution from the study "Possibilities and limits of independent living for elderly patients"].

In a study on the chances and limits of independent living in old age, we collected data about difficulties in 23 activities of daily living in two sub-samples: participants from the western part of Germany (n = 745), and from the eastern part of Germany (n = 347). Participants were grouped into three patterns of competence by means of cluster analysis. Cluster analyses were calculated separately for participants in the western and eastern parts of Germany. In both sub-samples, we found three patterns of competence: "High competence in most activities of daily living", "reduced competence in some activities of daily living" and "reduced competence in most activities of daily living". Patterns of competence were similar in the sub-samples, but important differences were found in some activities of daily living between participants from the eastern and western parts of Germany (e.g., in "heating home," "washing clothes," "banking"). These differences were due to unfavorable conditions in physical environment. Analysis of the relationship between objective housing conditions (assessed by our research team) and patterns of competence strongly supported this interpretation. Participants in the two sub-samples were more satisfied with their housing conditions as could be expected from our assessment of housing conditions. Successful adaptation to environmental conditions and changes in the aspiration-level can explain these differences. The degree of satisfaction with housing conditions is only a poor predictor for possibilities in increasing competence by intervention and rehabilitation. Most participants wished to keep their household independently as long as possible. Acceptance for homes for the elderly was low.

Activities of Daily Living↗

PubMed1977

A contrast of the three more common illnesses with the ten less common in a study and 18-month follow-up of 314 psychiatric emergency room patients.

An 18-month follow-up of 314 randomly selected psychiatric emergency room patients showed that, although there were 15 possible diagnostic groups the diagnoses made at initial interviews proved to be largely accurate. Follow-up results showed the prediction based on those initial diagnoses was 84% correct in the 299 patients (95%) that could be followed up. Follow-up results also showed that 88% of the individual diagnoses (as opposed to diagnosed patients) were correct. The kappa coefficients were high, all of them being above 0.60, some between 0.80 and 0.90. In addition to the relatively high diagnostic validity, the results also demonstrated a high item reliability for the more than 400 separate items for which kappa coefficients were calculated. Less than 15% of these items had a kappa coefficient of less than 0.60. This study thus demonstrated a high diagnostic reliability and a high diagnostic validity The basis of these diagnoses in a heterogeneous psychiatric population was the application of precisely defined and applied diagnostic criteria. The diagnostic process was blind in that the follow-up diagnosis was made in the absence of knowledge of the initial diagnosis. The use of precisely defined and systematically applied criteria may prove to be superior to multivariate analysis, cluster analysis, or other statistical techniques.

Adult↗

PubMed1995

Somatic complaints in the German population.

The Freiburg Complaint List (Freiburger Beschwerdenliste FBL-R) is a self-report questionnaire which consists of 80 somatic complaints. A survey was conducted in 1993 and a sample of N = 2070, representative for the German adult population of 16 years and above, was obtained. Factor analysis, cluster analysis and item analysis were employed to develop nine scales: General Condition, Tiredness, Cardiovascular, Gastrointestinal, Head-Throat, Tenseness, Emotional Reactivity, Pain, Sensory and Total Score. Regression analyses revealed substantial effects of gender, age group, and, to a lesser extent, social class on FBL-R scores. Furthermore, highly significant correlations were found between FBL-R scores and indicators of illness, health concern, and utilization of health services. The standardization provides normative data (stanine norms) that account for gender and age groups. This representative survey provides essential data, i.e. base rates of somatic complaints in the general population and subsamples. These base rates are relevant to the future development of criteria for diagnosis of somatization disorder.

Adult↗

PubMed1996

Macroinvertebrate community as a biological indicator of ecological and toxicological factors in Lake Saint-François (Québec).

To assess the potential of the macroinvertebrate community for monitoring variation in the environmental quality of large rivers, the response of littoral macrobenthos in Lake Saint-François, a fluvial lake of the St Lawrence River (Québec) are described. First, the composition of total macroinvertebrate communities and important taxonomic groups as well as the biotic ICI-SL index in 16 littoral stations varying in sedimentology, water chemistry and contamination are described to define indicator species groups and environmental quality ranks. Thereafter, the relative contribution of ecological and toxicological factors in explaining the variation observed in macroinvertebrate assemblages and biotic index were quantified using partial canonical correspondence analysis. Cluster analyses based on taxonomic composition separated five groups of stations where macroinvertebrate assemblages varied in density, composition and tolerance to pollution. The ICI-SL biotic index varied from 7.2 to 27.2 with a mean value of 19 +/- 6. The ICI-SL values determined for the macroinvertebrate communities in Lake Saint-François did not reflect an important deterioration in environmental quality, and there was some agreement between the environmental quality ranking of the stations expressed either by the ICI-SL index or the community cluster analysis. Water conductivity and phosphorus concentration, followed by macrophyte types (Chara, Ceratophyllum) and sediment grain size, were the most significant ecological variables to explain variation in macroinvertebrate communities and derived ICI-SL index in Lake Saint-François. Among the toxicological factors, metals in water (Fe, Cr, Pb, Mn, Zn) and sediment (Mn, Pb, Se), as well as the composite indices of metal and organic contamination (water CI, sediment CI, sediment total PAHs) were the most important factors. The contamination factors selected in our models represented contaminant sorption processes rather than direct toxicological effects. The lack of clear relationships between contaminants and macroinvertebrate variables reflected the relative low level of contamination in the stations sampled in Lake Saint-François. There were some interactions between toxicological and ecological variables that should be considered in the planning of sampling and interpretation of biomonitoring studies. However, the large amount of unexplained variance (49.2-86.6%) in the CCA models underlined the limitations of the use of the indices of macroinvertebrate community structure that were assessed in this study for biomonitoring purposes in the absence of a contrasting pollution gradient.

Journal Article↗

PubMed2006

An integrated impact assessment and weighting methodology: evaluation of the environmental consequences of computer display technology substitution.

Computer display technology is currently in a state of transition, as the traditional technology of cathode ray tubes is being replaced by liquid crystal display flat-panel technology. Technology substitution and process innovation require the evaluation of the trade-offs among environmental impact, cost, and engineering performance attributes. General impact assessment methodologies, decision analysis and management tools, and optimization methods commonly used in engineering cannot efficiently address the issues needed for such evaluation. The conventional Life Cycle Assessment (LCA) process often generates results that can be subject to multiple interpretations, although the advantages of the LCA concept and framework obtain wide recognition. In the present work, the LCA concept is integrated with Quality Function Deployment (QFD), a popular industrial quality management tool, which is used as the framework for the development of our integrated model. The problem of weighting is addressed by using pairwise comparison of stakeholder preferences. Thus, this paper presents a new integrated analytical approach, Integrated Industrial Ecology Function Deployment (I2-EFD), to assess the environmental behavior of alternative technologies in correlation with their performance and economic characteristics. Computer display technology is used as the case study to further develop our methodology through the modification and integration of various quality management tools (e.g., process mapping, prioritization matrix) and statistical methods (e.g., multi-attribute analysis, cluster analysis). Life cycle thinking provides the foundation for our methodology, as we utilize a published LCA report, which stopped at the characterization step, as our starting point. Further, we evaluate the validity and feasibility of our methodology by considering uncertainty and conducting sensitivity analysis.

Computer Terminals↗

PubMed1984

The syndrome concept: history and statistical operationalizations.

A historical analysis of the syndrome concept shows that this term has been used in many different ways, ranging from clinical experience to records of coinciding symptoms. However, there seems to be broad agreement on the use of the word 'syndrome' in daily practice. If empirical-mathematical methods are applied in syndrome detection, however, a precise operationalization of the syndrome concept is needed. Traditional procedures have often used models more dictated by methodological considerations than derived from the field of application, i.e. psychiatric syndromatology. An alternative approach, Boolean factor analysis, is presented in this paper. This relatively new method is illustrated by means of the analysis of a small artificial sample with a known structure. As a point of reference, traditional methods (factor analysis, cluster analysis, and multidimensional scaling) are also briefly discussed. It is demonstrated that they all share a deficiency of information about inter-group structure. In contrast, Boolean factor analysis uses a syndromic definition which builds on the basic notion of concurrent symptoms. Moreover, this approach can easily be understood by clinicians.

Computers↗

PubMed2004

Variations in rDNA ITS of Czech Armillaria species determined by PCR and HPLC.

We analysed 40 isolates of species Armillaria. borealis, A. cepistipes, A. gallica, A. mellea, A. ostoyae and A. tabescens, mostly collected in the Czech Republic, by PCR-RFLP of the ITS rRNA genes using the restriction endonucleases AluI, HinfI and MboI. Restriction fragments were analysed by ion-exchange high performance liquid chromatography which proved to be more useful informative, and less time-consuming than classical electrophoresis on agarose gel. The HPLC method enabled detection of some heterozygous strains. HinfI discriminated between all six species. Ten isolates were sequenced to confirm changes in restriction sites found by restriction analysis. Cluster analysis based on the restrictions patterns of restriction endonucleases AluI and HinfI divided the analysed species into three groups. The first and the most distant group contained all A. mellea isolates, the second group was formed by A. tabescens and the third group contained species A. borealis, A. cepistipes, A. gallica and A. ostoyae. The A. tabescens group was very homogenous regardless of the origin of isolates (Czech Republic, France and Finland).

Agaricales↗

PubMed2005

Chemometric characterization of the cypriot spirit "zivania".

In 42 alcoholic beverages produced in Cyprus and other countries, 26 chemical and physical-chemical variables were determined by HPLC and GC chromatography, (1)H NMR and ICP spectroscopy, and other techniques. Data were processed using multivariate chemometric techniques, involving principal component analysis, cluster analysis, regularized discriminant analysis, and classification and regression trees. Zivania can be differentiated from beverages from other countries. Using 2- and 3-methyl-butanol, 2-methyl-propanol, furfural, methanol, and the alcoholic grade and the chemical shift of -CH(3) in (1)H NMR spectra as features, a nearly correct classification for zivania was achieved. The reasons for diversions are given.

Alcoholic Beverages↗

PubMed2001

Evaluation of the effect of data pre-treatment procedures on classical pattern recognition and principal components analysis: a case study for the geographical classification of tea.

A simple transformation that uses the half-range and central value has been used as a data pre-treatment procedure for principal component analysis (PCA) and pattern recognition techniques. The results obtained have been compared with the results from classical normalisation of data (mean normalisation, maximum normalisation and range normalisation), autoscaling and the minimum-maximum transformation. Three data sets were used in the study. The first was formed by determining 17 elements in 53 tea samples (901 pieces of data). The second and third data sets arose from two long-term drift studies performed to examine instrumental stability at standard and robust conditions. The instruments used were an inductively coupled plasma atomic emission spectrometer and an inductively coupled plasma mass spectrometer. Each drift diagnosis experiment consisted of replicate determinations of a test solution containing 15 analytes at 10 mg l-1 over 8 h without recalibration. Twenty-nine emission lines were determined 99 times, thus, each data set was formed by 2881 pieces of data. Data pre-treatment was applied to the three data sets prior to the use of principal component analysis, cluster analysis, linear discrimination analysis and soft independent modelling of class analogy. The study revealed that the half-range and central value transformation resulted in a better classification of the tea samples than that achieved using the classical normalisation. The loadings in the PCA for the long-term stability study, under both standard and robust conditions, were found to be similar to the drift trends only when the minimum-maximum transformation and the mean or maximum normalizations were used as data pre-treatments.

Humans↗

PubMed1993

Alterations in phenotypic biochemical markers in bladder epithelium during tumorigenesis.

Phenotypic biochemical markers of oncogenesis and differentiation were mapped in bladder biopsies to investigate changes that occur in bladder tumorigenesis and to identify markers for increased bladder cancer risk. Touch preparations from biopsy specimens from 30 patients were obtained from tumors, the adjacent bladder epithelium, and random distant bladder epithelium. Markers, including DNA ploidy, epidermal growth factor receptor (EGFR), and oncoproteins, were quantified in individual cells by using quantitative fluorescence image analysis. Cluster analysis revealed the markers fell into three independent groups: (i) G-actin and EGFR; (ii) ploidy, cytology, and p185 (HER-2/neu oncoprotein) (ERBB2); and (iii) p300, a low-grade tumor antigen. Each marker displayed a gradient of abnormality from distant field to adjacent field to tumor. Different patterns for each marker suggested a developmental sequence of bladder cancer oncogenesis; G-actin was altered in 58% of distant biopsies (vs. 0/6 normals, P < 0.001), ploidy and cytology were altered in < 20% of distant fields and approximately 80% of tumors, and the other markers were intermediate. Patterns of EGFR and p185 suggest low-and high-grade tracks diverge early (P < 0.05 by Mann-Whitney U test for EGFR and ANOVA for p185). In conclusion, this study shows that a sequence of phenotypic changes accompanies development and progression of bladder cancers. Biochemical alterations in cells of the bladder field are often detectable before abnormal pathology, and markers previously thought to be limited to tumors were found in the field. The hierarchy of expression may be useful in identifying high-risk patients, assessing completeness of response to therapy, and monitoring and predicting recurrence.

Analysis of Variance↗

PubMed2003

Virulence and molecular typing of Vibrio harveyi strains isolated from cultured dentex, gilthead sea bream and European sea bass.

Vibrio harveyi was isolated from internal organs or ulcers of diseased and apparently healthy gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax) cultured in several fish farms located on the Spanish Mediterranean coast. The prevalence of the bacterium was significantly higher in European sea bass than in gilthead sea bream, and was closely related to the season in both fish species, occurring almost exclusively on warm months (June to November). After phenotypic characterization, a selection of forty five isolates from gilthead sea bream, sea bass, and several isolates previously obtained from common dentex (Dentex dentex) of the same area, were molecularly typed by automated ribotyping and random amplified polymorphic DNA (RAPD) analysis. Cluster analysis of data established 8 RAPD types and 13 ribotypes among wild isolates, and the combination of both techniques allowed to define fourteen different groups and a clear discrimination of all outbreaks and samplings. Several strains isolated from diseased gilthead sea bream and sea bass and also from asymptomatic sea bream, were tested for virulence in both fish species by intracoelomic injection. All the isolates (11) were pathogenic for sea bass, with nine out of the eleven LD50 values ranging from 1.5 x 10(5) to 1.6 x 10(6) cfu/fish. Gilthead sea bream was unaffected by the seven tested strains, even by those more virulent for sea bass, and only one strain caused a 10% mortality at 4.2 x 10(7) cfu/fish. This is the first report on virulence of V. harveyi for sea bass.

Animals↗

PubMed1995

A preliminary investigation of affective and cognitive response to erotic stimulation in men before and after sex therapy.

Affective and cognitive responses to erotic stimulation were studied in sexually dysfunctional men before and after treatment in a sex therapy program. A comparison group of functional men was studied over the same time interval. A pool of 34 Likert-scaled items assessing various cognitions, affects, and perceptions was administered during baseline and following two erotic audiotapes and a self-generated sexual fantasy. To focus on global response patterns rather than individual item responses, five aggregate indices (sexual arousal, physicality, sensuality, negative affect, positive affect) were derived using a strategy that combined face-validity and reliability analysis. Cluster analysis was employed as an auxiliary technique to confirm the coherence of these groupings. All five indices differentiated dysfunctional men from controls, and further, three indices (physicality, sensuality, sexual arousal) showed significant variation across types of erotic stimulation. Correlations among the five indices, as well as with penile response, revealed two trends that differentiated dysfunctional men from controls during the pretest, but that diminished following sex therapy in the dysfunctional men. Future investigations might further rely on multiple-item indices as described here. Such measures may provide a more integrated view of sexual response in the laboratory and lead to greater understanding of affective and perceptual differences between functional and dysfunctional men.

Adult↗

PubMed2000

A population-based analytical approach to assessing patterns, determinants, and outcomes of health care with application to ectopic pregnancy.

OBJECTIVE: Health care has variable features, specific determinants, and consequences on people's health that should be investigated in a population perspective. We present a population-based analytical approach to assessing patterns, determinants, and outcomes of health care. METHODS: The approach uses standard epidemiological methods for sample selection and analysis, as well as statistical methods concerning model fitting and validation strategy. It also uses psychometric methods allowing pattern identification: factor analysis, cluster analysis, and polytomous logistic regression to investigate the factors associated with identified patterns of care. The approach is illustrated with an application to ectopic pregnancy (EP). RESULTS: EP diagnostic and therapeutic procedures appeared to be closely related, suggesting 3 differentiated patterns of care. Predictors of these patterns were not only the clinical features and the woman's prior gynecological history but also center characteristics and location. These patterns were found to influence immediate and middle-term outcomes and risk of recurrence of EP. CONCLUSIONS: We illustrate the feasibility and profitability of a population-based analytical approach to identify patterns, determinants, and consequences of care. This approach could be used to analyze other pathological conditions and health care systems.

Adolescent↗

PubMed2004

Transcriptional response to corticotropin-releasing factor in AtT-20 cells.

Corticotropin-releasing factor (CRF) plays a central role in the regulation of the hypothalamic-pituitary-adrenal axis, mediating endocrine and behavioral responses to various stressors. Two high-affinity receptors for CRF have been described. Although many of the intracellular signaling pathways activated by CRF have been studied extensively, our knowledge of transcriptional responses downstream of the CRF receptor 1 (CRFR1) is still limited. To elucidate gene networks regulated by CRF and CRFR1, we applied microarray technology to explore transcriptional response to CRF stimulation. Therefore, mouse pituitary-derived AtT-20 cells were exposed continuously to CRF either in the presence or absence of the specific CRFR1 antagonist R121919. Transcriptional responses to different treatments were studied in a time course ranging from 0.5 to 24 h. Microarray data were analyzed using classic microarray data analysis tools such as correspondence factor analysis, cluster analysis, and fold-change filtering. Furthermore, spectral map analysis was applied, a recently introduced unsupervised multivariate analysis method. A broad and transient transcriptional response to CRF was identified that could be blocked by the antagonist. This way, several known CRF-induced target genes and novel CRF responsive genes were identified. These include transcription factors such as cAMP-responsive element modulator (7x increased), secreted peptides such as cholecystokinin (1.5x), and proteins involved in modulating intracellular signaling, such as regulator of G-protein signaling 2 (11x). Up-regulation of many of these genes can be explained as negative feedback, attenuating CRF-activated pathways. In addition, spectral map analysis proved to be a promising new tool for microarray data analysis.

Animals↗

PubMed1998

Gradual molding of the hand to object contours.

Subjects were asked to reach to and to grasp 15 similarly sized objects with the four fingers opposed to the thumb. The objects' contours differed: some presented a concave surface to the fingers, others a flat one, and yet others a convex surface. Flexion/extension at the metacarpal-phalangeal and proximal interphalangeal joints of the fingers was recorded during the reaching movement. We used discriminant analysis, cluster analysis, and information theory to determine the extent to which the shape of the hand was affected by the objects' shapes along a convexity/concavity gradient. Maximum aperture of the hand was reached about midway in the reaching movement. At that time, the hand's posture was influenced by the shape of the object to be grasped but imperfectly. The information transmitted by hand posture about object shape increased gradually and monotonically as the hand approached the object, reaching a maximum at the time the object was in the grasp of the hand. We also asked subjects to shape the hand so as to grasp the object without moving the arm. Their performance was poorer on this task in the sense that hand shape discriminated among fewer objects and that trial-to-trial variability was greater than when the distal and proximal components of the motion were linked. The results indicate that the hand is molded only gradually to the contours of an object to be grasped. Because other parameters of the motion, such as movement direction, for example, already are specified fully early on in a movement, the results also suggest that the specification of diverse aspects of a movement does not evolve at a uniform rate.

Arm↗

PubMed1989

Differential classification in school refusal.

It has been argued that school refusal may not be a unitary syndrome, but a common presenting symptom founded on differing underlying dynamics. The paper explores this hypothesis empirically. The clinical files of 100 refusers were scored for several variables which could potentially differentiate between school refusal subtypes, and for several commonly accepted beliefs about school refusal. The data were subjected to a variety of analyses, culminating in cluster analysis. Cluster (C) 1 consisted of children who feared separation from dependent, overprotective mothers. C2 youngsters were perfectionistic and depressed. They dominated mothers who had been deprived in childhood. C3 consisted of extensively disturbed children from multiproblem families, who had suffered early separation or loss, and who were fearful and depressed.

Child↗

PubMed2004

Interpretation and impression of ambiguous eye gaze of a mother and child in a Japanese traditional picture.

Using various compositions with alterations in figures' gaze directions and additions of an object, the interpretation of gaze directions and the impression of a figure were examined. The results obtained by factor analysis, cluster analysis, multi-dimensional scaling and questionnaires showed that 1) observers' impression of a figure was affected not only by figures' gaze directions but also by the presence or absence of an object viewed by figures, 2) compositions of joint attention gave a positive impression even if in an averted composition (parallel joint attention), 3) the pictures used here were viewed from the point of view of the attachment of mothers and the independence of children, and 4) a woman in this picture was evaluated from the aspect of a motherhood or pre-motherhood impression. These results are discussed in terms of the cognitive process of gaze directions as well as the developmental process of the mother-child relationship.

Adult↗