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PubMed1985

Brainstorming: an application for programme planning in family welfare planning.

There have been many participatory devices developed and applied for programme planning in a variety of fields by the social scientists in the recent past, of which brainstorming is one. This device has been widely used in interpretive structural modelling to higher education programme planning, programme planning for housing in urban development, etc. Following these studies, application of brainstorming to develop a preliminary operational value system as a structural model for programme planning in Family planning was attempted. The products of a sequence of three sessions of approximately 5 hours each generated 39 needs, 28 alterables, and 22 constraints, all of which were used to set Family Planning objectives /34/. The objectives thus derived were used in building an intent structure to understand their priorities in plan formulation and eventual implementation.

Communication↗
PubMed1974

Immunologic enhancement of rat renal allografts. I. Comparative morphology of acutely rejecting and passively enhanced grafts.

The acute unmodified rejection of (Lewis x Brown Norway) F(1) to Lewis renal allografts is characterized by an early and progressive lymphoid cell infiltrate, glomerular necrosis, necrotizing arteritis and ischemic cortical necrosis leading to graft destruction. A single low dose of enhancing antiserum given at the time of transplantation prolongs graft survival by abrogating the necrotizing lesions in glomeruli and arteries and the subsequent cortical necrosis. Passive enhancement in this model is interpreted as representing predominantly a block in the humoral antibody-mediated rejection response. It is suggested that the block is effected mainly, peripherally, ie, at the level of the transplanted kidney itself.

Animals↗
PubMed1981

Generation of free radicals induced by nifurtimox in mammalian tissues.

Nifurtimox is reduced by rat liver microsomes to a nitro anion-free radical as indicated by ESR spectroscopy. This subcellular fraction gives a steady state radical concentration which is proportional to the square root of the protein concentration, suggesting that the nifurtimox anion radical is a necessary intermediate in the reduction and that the radical decays through a nonenzymatic second order process. The steady state concentration of the anion radical in the microsomal system is not decreased by superoxide dismutase or catalase, thus indicating that neither the superoxide anion nor hydrogen peroxide is an intermediary in the generation of the anion radical. The steady state concentration of the anion radical in the microsomal system is also not altered in the presence of metyrapone or CO and is decreased in the presence of NADP+ and p-chloromercuribenzoate. This observation suggests that the formation of nifurtimox anion radical is mediated through NADPH-cytochrome P-450 (c) reductase and not by the cytochrome P-450 system. In accordance with this interpretation, a model system consisting of NADPH and FMN-reduced nifurtimox to the nitro anion-free radical. Nifurtimox anion radical generation is significantly stimulated by rat brain and testes homogenates. The enhanced free radical formation may be the basic cause of nifurtimox toxicity in mammals.

Animals↗
PubMed1978

Psychological aspects of rheumatoid arthritis vis-à-vis osteoarthrosis.

Using objective techniques (M.M.P.I; M.H.P.A.; ANAM; S.T.A.I.), a transverse investigation of two groups of arthritic patients (35 rheumatoid arthritis and 30 oesteoarthrosis) was carried out. The Rheumatoid Arthritis (RA) patients evidence greater depression (p less than 0.02), while the osteoarthrosis (OA) patients had higher levels of manifest aggressivity (p less than 0.01) and more somatic preoccupation (p less than 0.02). The RA group had a higher incidence of loss of a family member as a preceding life event (p less than 0.05), and a greater incidence of psychopathological problems in infancy (p less than 0.05). These findings were used to construct an interpretative hypothetical model which represents a starting point and a stimulus for future research.

Aggression↗
PubMed1980

[Chronicity in ambulatory practice: doctor-patient relationship perspectives].

On the base of his own experience in the doctor's office, as a supervising therapeut in institutions and as a leader of Balintgroups with interns of psychiatry, the author reflects on different aspects of chronicity dealing not so much with the disease of the patient itself as with its relation to the doctor. Thereby reference is made to the danger of typisized acting in relations and stereotypical diagnosis. On the other hand the possibilities of insight in relational perspective shall be demonstrated, e.g. an entrance to the patient favoring the individual experience to the typical and involving the empathic fantasy of the doctor as an instrument of work. From such a point of view, diagnosis become what they are, namely relation-depending interpretations and models of insight and consequently chronicity is looked upon with a primary understanding. Proposition is made to distinguish a "malignant" chronicity from a "benign" one, the former giving way to chronic illness of the patient, whereas the latter means a lasting therapeutical relation open to progress.

Chronic Disease↗
PubMed1995

Chemosensitivity testing of human tumors using a microplate adenosine triphosphate luminescence assay: clinical correlation for cisplatin resistance of ovarian carcinoma.

An ATP luminescence assay (TCA 100) was used to measure chemotherapeutic drug sensitivity and resistance of dissociated tumor cells cultured for 6 days in serum-free medium and 96-well polypropylene microplates. Studies were performed with surgical, needle biopsy, pleural, or ascitic fluid specimens using 10,000-20,000 cells/well. ATP measurements were used to determine tumor growth inhibition. Single agent and drug combinations were evaluated using the area under the curve and 50% inhibitory concentration (IC50) results for a series of test drug concentrations. The ATP luminometry method had high sensitivity, linearity, and precision for measuring the activity of single agents and drug combinations. Assay reproducibility was high with intraassay and interassay coefficients of variation of 10-15% for percentage of tumor growth inhibition, 5-10% for area under curve, and 15-20% for IC50 results. Good correlation (r = 0.93) between the area under the curve, and IC50 results was observed. Cytological studies with 124 specimens demonstrated selective growth of malignant cells in the serum-free culture system. Studies with malignant and benign specimens also showed selective growth of malignant cells in the serum-free medium used for assay. The assay had a success rate of 87% based on criteria for specimen histopathology, magnitude of cell growth, and dose-response drug activity. Cisplatin results for ovarian carcinoma are presented for 81 specimens from 70 untreated patients and 33 specimens from 30 refractory patients. A model for interpretation of these results based on the correlation of clinical response with the area under the curve and IC50 results indicates that the assay has > 90% accuracy for cisplatin resistance of ovarian carcinoma. Additional studies are in progress to evaluate the clinical efficacy of this assay.

Adenosine Triphosphate↗
PubMed1994

Testing hypotheses on processes of genetic and linguistic change in the Caucasus.

Extensive genetic diversity exists in the populations of the Caucasus. Various hypotheses on its origin and evolution were tested by comparing genetic, geographic, and linguistic distances. Seventeen polymorphic loci and 107 localities were considered, and Mantel tests of matrix association were carried out. Genetic differences correlate more with linguistic than with geographic distances; but when populations are grouped by the language spoken, this correlation loses significance, whereas genetic and geographic distances between groups appear significantly associated. Hypotheses that classify North and South Caucasian languages into distinct families or that treat all North Caucasian languages as independent linguistic entities fail to account for genetic variation better than simpler models. We interpret these results as evidence for an evolutionary process in which linguistic and genetic divergence has resulted from population subdivision and from processes of elite dominance, that is, language replacement not associated with major migratory movements.

Alleles↗
PubMed1993

Optical spectropotentiometric resolution of the hemes of hydroxylamine oxidoreductase. Heme quantitation and pH dependence of Em.

The hemes of hydroxylamine oxidoreductase (HAO) have been analyzed optically by potentiometric titrations using a low volume optically transparent thin layer electrochemical cell. The electrochemical behavior of the HAO monomeric unit has been interpreted by modeling the spectroelectrochemical data at several wavelengths to eight one-electron Nernst sites: seven c-type hemes and one P460 heme. Of the seven c-hemes, six show alpha-bands with absorption maxima at or near 553 nm. One c-heme has an alpha-band absorption maximum at 559 nm. The six c-553 hemes have midpoint potentials at pH 7.0 of +288, -10, -162, -192, -265 and -412 mV versus the normal hydrogen electrode (NHE). The c-559 heme has a midpoint potential (Em') at pH 7.0 of +11 mV versus NHE. The midpoint potential of the P460 heme is at -260 mV versus NHE at pH 7.0. In contrast, the midpoint potential for the P460 heme in another protein, cytochrome P460, from the same organism is -402 mV versus NHE at pH 7.0. Midpoint potentials of the c-hemes show little, if any, pH dependence over the range of pH 6-8. In contrast, Em' for the P460 heme changes with a slope of -60 mV/pH unit over the same range. Electrochemical isolation of the P460 heme at pH 8.0 led to the discovery of a broad spectroscopic feature centered near 740 nm that was assigned to the oxidized P460 heme. Changes in the spectroelectrochemical behavior of HAO after inactivation by H2O2 was almost exclusively restricted to the P460 heme of HAO. Both the 464-nm absorption band of the reduced P460 heme and the 740-nm band of the oxidized heme were no longer present. For the c-hemes, the only effect seems to be a slight shift in Em' for a single c-553 heme from -162 to -135 mV.

Cytochromes↗
PubMed1993

Concepts of reality and psychic reality in psychoanalysis as illustrated by the disagreement between Freud and Ferenczi.

In this paper, the concepts of reality and psychic reality are discussed in relationship to a number of controversies about the therapeutic and scientific aims of psychoanalysis, as illustrated by the disagreement between Freud and Ferenczi. Because the nature of psychic reality is necessarily incomplete and indeterminate, there are inherent limitations and dangers to any psychoanalytic attempt to discover historical and experiential truth. Modell's interpretation of Nachträglichkeit ('deferred action') as 'retranscription' expresses the ambiguity of psychic reality in analysis, which is not fixed or foundational but part of an evolving inner and outer dialogue in relation to new experience. It is argued that Freud accepted this ambiguity, while Ferenczi sought to overcome it through modifications of technique.

Freudian Theory↗
PubMed1997

Arrhythmia curve interpretation using a dynamic system model of the myocardial pacemaker.

A problem of identifying the phase response curve of the myocardial pacemaker was investigated using a simple dynamic system model of cardiac arrhythmia. A hybrid optimization method of a genetic algorithm and a local optimization technique was employed to obtain a solution of the model fitting. The method was applied to two categories of arrhythmias, ventricular parasystole and high-degree AV block. The present study offered a new insight into the mechanism of cardiac arrhythmias.

Animals↗
PubMed1998

Detection of chromosomal gains and losses in comparative genomic hybridization analysis based on standard reference intervals.

Criteria for detection of chromosome aberrations by Comparative Genomic Hybridization (CGH) are not standardized and improvement of this part of the analysis is of paramount importance to the applicability of the technique. The aim of this work was to suggest CGH detection criteria that increase the specificity and sensitivity and at the same time include chromosome regions previously excluded from CGH analysis. We analyzed 33 hybridizations with normal DNA and modified our CGH software in order to use a selection of these normal analyses as a model for interpretation of analyses of unknown samples. This approach was successfully tested on 14 samples with known aberrations.

Chromosome Aberrations↗
PubMed2005

Cue interaction effects in causal judgement: an interpretation in terms of the evidential evaluation model.

In judging the extent to which a cue causes an outcome, judgement can be affected by information about other cues that are correlated with the one being judged. These cue interaction effects have usually been interpreted in terms of associative learning processes. I propose that a different model of causal judgement, the evidential evaluation model, offers a viable alternative interpretation of cue interaction phenomena. Under the evidential evaluation model, instances of contingency information are interpreted as evidence, which is confirmatory, disconfirmatory, or irrelevant for the cue being judged. When two cues co-occur in a set of instances the evidential value of the instances for one of them is determined by three factors: the proportion of confirming instances in the set; disambiguation value, which concerns the relation between the set of information and prior beliefs about the co-occurring cue; and confirmation value, which concerns the relation between the set of information and prior beliefs about the cue being judged. Any previous judgement of the cue is then modified in the light of these. It is shown that this model can account for all the cue interaction phenomena that have been investigated in studies of human causal judgement. The model also generates novel predictions, and the results of three experiments give support to these predictions. It is also shown that several other current models of causal judgement fail to predict a key result from Experiment 3.

Analysis of Variance↗
PubMed1986

Perioral behaviors induced by cholinesterase inhibitors: a controversial animal model.

Perioral behaviors induced by neuroleptic drugs have been interpreted as an animal model of tardive dyskinesia. However, these behaviors have also been induced or enhanced by physostigmine, a cholinesterase inhibitor. The latter result is contradictory to the clinical effect of physostigmine in human tardive dyskinesia. In view of this contradiction and other considerations, perioral behaviors have also been interpreted as a model of acute dystonia. The present experiments replicated an earlier failure to observe spontaneous perioral behaviors after long-term neuroleptic treatment in rats as well as the paradoxical effect of physostigmine. The effect of physostigmine was also compared to phenylmethanesulfonyl fluoride and methanesulfonyl fluoride, irreversible CNS active cholinesterase inhibitors. There were significant differences between the effects of the various cholinesterase inhibitors and their interactions with perioral behaviors and neuroleptic treatment. It is concluded that the effects of cholinesterase inhibitors on perioral behaviors in rodents may not be accounted for entirely by cholinesterase inhibition. Further experiments using additional agonists and antagonists will be required to clarify the behavioral effects of these cholinesterase inhibitors.

Animals↗
PubMed2003

Estimation of primary drainage three-phase relative permeability for organic liquid transport in the vadose zone.

The modeling of transport of organic liquid contaminants through the vadose zone often requires three-phase relative permeabilities. Since these are difficult to measure, predictive models are usually used. The objective of this study is to assess the ability of eight common models to predict the drainage relative permeability to oil in a three-phase system (water-oil-air). A comparison of the models' estimates using data set from Oak [Oak, M.J., 1990. Three-phase relative permeability of water-wet Berea. In: Seventh Symposium on Enhanced Oil Recovery, Paper SPE/Doe 20183. Tulsa, OK, April 22-25] showed that they provide very different predictions for the same system. The goodness of the models does not increase with the amount of data or computation that the models require. Also, the calculations showed how different interpretations of the models and of the terminology associated with them can significantly impact the predictions. Thus, considerable error may be introduced into the simulations of organic liquid transport in the vadose zone depending on the selection and interpretation of the three-phase relative permeability model.

Filtration↗
PubMed1989

Realistic conductivity geometry model of the human head for interpretation of neuromagnetic data.

In this paper, the computational and practical aspects of a realistically-shaped multilayer model for the conductivity geometry of the human head are discussed. A novel way to handle the numerical difficulties caused by the presence of the poorly conducting skull is presented. Using our method, both the potential on the surface of the head and the magnetic field outside the head can be computed accurately. The procedure was tested with the multilayer sphere model, for which analytical expressions are available. The method is then applied to a realistically-shaped head model, and it is numerically shown that for the computation of B, produced by cerebral current sources, it is sufficient to consider a brain-shaped homogeneous conductor only since the secondary currents on the outer interfaces give only a negligible contribution to the magnetic field outside the head. Comparisons with the sphere model are also included to pinpoint areas where the homogeneous conductor model provides essential improvements in the calculation of the magnetic field outside the head.

Brain↗
PubMed2005

Ultrafast far-infrared dynamics probed by terahertz pulses: a frequency-domain approach. II. Applications.

We present data obtained by time-resolved terahertz spectroscopy in selected semiconducting and molecular systems exhibiting subpicosecond far-infrared dynamics. We use a frequency-domain method which eliminates the influence of instrumental functions and artifacts due to frequency mixing and yields a two-dimensional transient conductivity of the photoexcited sample. This technique enables improving the attainable experimental time resolution and allows a simple qualitative interpretation of the results without a priori modeling. The quantitative interpretation is based on the time-dependent Drude and damped harmonic oscillator models.

Journal Article↗
PubMed2003

The theoretical status of latent variables.

This article examines the theoretical status of latent variables as used in modern test theory models. First, it is argued that a consistent interpretation of such models requires a realist ontology for latent variables. Second, the relation between latent variables and their indicators is discussed. It is maintained that this relation can be interpreted as a causal one but that in measurement models for interindividual differences the relation does not apply to the level of the individual person. To substantiate intraindividual causal conclusions, one must explicitly represent individual level processes in the measurement model. Several research strategies that may be useful in this respect are discussed, and a typology of constructs is proposed on the basis of this analysis. The need to link individual processes to latent variable models for interindividual differences is emphasized.

Humans↗