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At least 793 records · Page 44Linked to original sources
PubMed1984

Faculty and administrator perceptions of decision making.

This research study was conducted in associate and baccalaureate schools of nursing. This research focused on the extent of faculty participation in decision making; a description and analysis of the characteristics of nurse faculty, nurse administrators, and the organizations of associate and baccalaureate schools of nursing; the interrelationships between opportunities for participation in decision making and the level and type of decision making; the relationships between various personal and situational variables that affect decision making, the relationship between the type of involvement in decision making to the variables of job satisfaction, professional commitment, and job tension; and the relationships among the variables of job satisfaction, professional commitment and job tension. Ninety-three faculty and 10 administrators participated in the research study. Research data were collected by three instruments: the School Information Profile, the Administrative Questionnaire, and the Faculty Questionnaire. The data were subjected to frequency distribution statistics, the RELIABILITY program of SPSS, Pearson correlation coefficients, Canonical correlations, and Multiple Regression analysis. The primary study results were: Faculty reported that their participation in decision making is primarily in the area of making recommendations, not final determinations. Faculty stated that decision making is usually a group process. Administrator perceptions were that faculty possess more decision-making power than faculty believed. Faculty reaffirmed that job satisfaction and professional commitment are positively correlated, and that job tension was found to be negatively correlated to job satisfaction and professional commitment.(ABSTRACT TRUNCATED AT 250 WORDS)

Administrative Personnel↗
PubMed1999

[Development and evaluation of a photo-rhinometer for clinical use].

We developed a photo-rhinometer (PRM) which is a modification of the Glatzel nasal mirror, and which can promptly evaluate nasal patency under natural respiration without any facial apparatus. We also investigated the clinical applications of the PRM. In PRM operation, moisture deposits resulting from expiratory nasal flow onto a glass plate are visualized for the right and left nostrils separately with an image analyzing computer at a television scan rate of 1/30 of a second. These visualized moisture deposits are averaged over the initial 1 second and differentiated for the initial 90 milliseconds to obtain an average moisture deposit area (AMDA) and the velocity of the moisture deposit (VMD), respectively. The resulting PRM chart, a graphic presentation of the moisture deposit area versus time was expected to be useful for the visual evaluation of nasal patency. PRM measurements were performed on 100 adult volunteers who were selected without knowing whether they had any nasal symptoms or disorders. Results showed that statistical distributions of both AMDA and VMD were equivalent to the normal distribution. A significant correlation was observed between nasal conductance as determined by a rhinomanometer and AMDA as determined by the PRM, and also between the nasal conductance and the VMD, which is r = 0.66 and r = 0.78 respectively. In addition to the 100 cases, five cases of chronic sinusitis and ten cases of acute sinusitis, which had been conservatively treated, were investigated by using the PRM. In some of these cases where improvements in the nasal conditions and reduction of subjective nasal obstruction were recognized, increases in the AMDA and VMD showed a good correlation with improvements in the nasal disorder.

Adult↗
PubMed2006

Altered self-erythrocyte recognition and destruction in an inbred line of tilapia (Oreochromis aureus).

Carboxyfluorescein diacetate (cFDA)-stained autologous and syngeneic tilapia (Oreochromis aureus) erythrocytes are recognized by effector peripheral blood leukocytes and lysed after a short culture period of 4 h. The hemolysis level was evaluated by measuring the fluorescence of the released cFDA. The degree of lysis of stained target erythrocytes of 60 individuals revealed a trimodal distribution statistically stratified into three groups of low (LR), intermediate (IR), and high (HR) responders. Depletion of the majority of phagocytes from leukocytes lowered the lysis level of HR to that of LR. A highly significant increase of LR cytotoxicity was obtained after the addition of conditioned medium from HR but only in the presence of phagocytes. Genetic analysis of offspring from four crosses (IR x HR, IR x LR, HR x LR, and LR x LR) revealed a quantitative trait locus (QTL) segregating for the level of response linked to markers UNH207 and UNH231 on linkage group 6 of tilapia. Based on segregation analysis of 58 gynogenetic BIU-1 offspring, the distances from the centromere were estimated as 21.5, 11.5, and 9.0 cM for UNH207, UNH231, and the QTL, respectively. It is suggested that 1) self-target recognition and destruction requires both cFDA-altered self-erythrocyte membrane and membrane structures normally present in autologous, syngeneic, and xenogeneic targets; 2) natural cytotoxic cells and/or macrophages are involved in erythrocyte lysis; and 3) the lysis level is codominantly inherited by a QTL segregating on tilapia linkage group 6.

Animals↗
PubMed2006

A probabilistic modeling approach in thermal inactivation: estimation of postprocess Bacillus cereus spore prevalence and concentration.

The survival of spore-forming bacteria is linked to the safety and stability of refrigerated processed foods of extended durability (REPFEDs). A probabilistic modeling approach was used to assess the prevalence and concentration of Bacillus cereus spores surviving heat treatment for a semiliquid chilled food product. This product received heat treatment to inactivate nonproteolytic Clostridium botulinum during manufacture and was designed to be kept at refrigerator temperature postmanufacture. As key inputs for the modeling, the assessment took into consideration the following factors: (i) contamination frequency (prevalence) and level (concentration) of both psychrotrophic and mesophilic strains of B. cereus, (ii) heat resistance of both types (expressed as decimal reduction times at 90 degrees C), and (iii) intrapouch variability of thermal kinetics during heat processing (expressed as the time spent at 90 degrees C). These three inputs were established as statistical distributions using expert opinion, literature data, and specific modeling, respectively. They were analyzed in a probabilistic model in which the outputs, expressed as distributions as well, were the proportion of the contaminated pouches (the likely prevalence) and the number of spores in the contaminated pouches (the likely concentration). The prevalence after thermal processing was estimated to be 11 and 49% for psychrotrophic and mesophilic strains, respectively. In the positive pouches, the bacterial concentration (considering psychrotrophic and mesophilic strains combined) was estimated to be 30 CFU/g (95th percentile). Such a probabilistic approach seems promising to help in (i) optimizing heat processes, (ii) identifying which key factor(s) to control, and (iii) providing information for subsequent assessment of B. cereus resuscitation and growth.

Bacillus cereus↗
PubMed2003

[The lambda in the rorschach comprehensive system].

The purpose of the present study was to investigate the relationships between Lambda (L) and other variables in the Rorschach comprehensive system. Individual Rorschach tests based on the comprehensive system was administrated to 102 female normal adults (over 20 years old). High L group and Low L group were defined on the basis of median value. The two groups were compared on major variables. The high L group had significantly higher values on variables such as DQo, D, Dd, S, Hd than the low L group. In contrast, the low L group had significantly higher values on variables such as DQ+, Blends, M, FM + m, Sum C', "active", H, COP than the high L group. Clinician who use the Rorschach test should consider these variables in relation to L, when interpreting the structural summary of the comprehensive system.

Adult↗
PubMed1996

The trough: peak ratio and the normalization of blood pressure profiles.

Experts from the Food and Drug Administration (FDA) of the USA have assumed that hypertensive patients are likely to achieve greatest benefit from therapy in which the antihypertensive effects do not vary excessively during the course of the day. They suggested that the ratio of the minimal (trough) effect to the maximal (peak) effect of the drug should be no lower than 0.5. The concept of the trough: peak ratio (TPR) raises many practical problems. Using actual data, the effect of a drug often shows erratic fluctuations with several local minima and maxima. Mean blood pressure levels for several hours have been used to estimate the trough and peak effects. Blood pressure averages over 4 h may e a good choice, because blood pressures measured 4 h apart are not correlated. The statistical distribution of the TPR is not Gaussian. Negative and very low or positive and very high individual ratios are frequently observed. Therefore, the individual TPR is of questionable clinical value, except when the ratio is applied for responders only. The TPR can be calculated for a sample. In that case, the bootstrap method can be used to estimate the error of the TPR. Most important is the question of why the TPR should be higher than 0.5. We introduced the concept of 'normalization of the blood pressure profile', namely 'reducing the blood pressure profiles in hypertensives to match those profiles in normotensives'. This concept leads very naturally to the TPR and justifies the lower limit of 0.5 for the TPR.

Journal Article↗
PubMed1999

A radionuclide therapy treatment planning and dose estimation system.

UNLABELLED: An object-oriented software system is described for estimating internal emitter absorbed doses using a set of computer modules operating within a personal computer environment. The system is called the Radionuclide Treatment Planning and Absorbed Dose Estimation System (RTDS). It is intended for radioimmunotherapy applications, although other forms of internal emitter therapy may also be considered. METHODS: Four software modules interact through a database backend. Clinical, demographic and image data are directly entered into the database. Modules include those devoted to clinical imaging (nuclear, CT and MR), activity determination, organ compartmental modeling and absorbed dose estimation. RESULTS: Both standard phantom (Medical Internal Radiation Dose [MIRD]) and patient-specific absorbed doses are estimated. All modules interact with the database backend so that changes in one process do not influence other operations. Results of the modular operations are written to the database as computations are completed. Dose-volume histograms are an intrinsic part of the output for patient-specific absorbed dose estimates. A sample dose estimate for a potential 90Y monoclonal antibody is described. CONCLUSION: A four-module software system has been implemented to estimate MIRD phantom and patient-specific absorbed doses. Computations of the doses and their statistical distribution for a pure beta emitter such as 90Y take approximately 1 min on a 300 MHz personal computer.

Humans↗
PubMed1999

[Computer-based image analysis for experimental and clinical morphology--principles, utilization and marginal limits].

The new computer based image analysis techniques are powerful tools for mophometrical and quantitative image analysis in case of clinical and experimental morphology. Digital image analysis requires a distinction between two phases 1. generation of fundamental data (x,y coordinates and grey values of the pixel) and 2. calculation of parameters from these data. Stereological procedures are very powerful in quantifying morphological phenomenons, but computer based image analysing techniques allow multiple analysis of morphological objects and analysis of statistical distributions. There is great scientific benefit using modern computer based image analysing techniques.

Animals↗
PubMed1999

Chromatin texture in high grade prostatic intraepithelial neoplasia and early invasive carcinoma.

OBJECTIVE: To evaluate individual nuclei from high grade prostatic intraepithelial neoplasia (PIN) lesions with early invasive carcinoma foci in the area of microinvasion and in the gland in which the microinvasion originated. STUDY DESIGN: High-resolution, digitized images of nuclei from defined locations were recorded and segmented, and karyometric variables were computed. These included a set of 93 features, which form a nuclear signature characterizing the spatial and statistical distribution of the nuclear chromatin. Nuclei in the glandular epithelium were recorded sequentially, along the basal cell layer, at increasing distances from the point of microinvasion and by random selection in the region of microinvasion. RESULTS: At a distance > 60 nuclear locations from the point of microinvasion, the nuclear signatures corresponded to those seen in high grade PIN. Between 40 and 20 nuclear locations removed from the microinvasion focus the signatures began to change gradually until at a distance of 15-5 locations they strongly resembled the signatures seen in adenocarcinoma. The total optical density decreased to values seen in adenocarcinoma, and the nuclear chromatin had finer granularity. While nuclei in high grade PIN followed a widely dispersed total optical density distribution suggestive of wide-ranging aneuploidy, the nuclei in the region of microinvasion exhibited a less dispersed and bimodal total optical density distribution. CONCLUSION: The chromatin texture signatures showed a clear trend: there was an obvious attenuation as the measured nuclei approached the microinvasion area. The decrease in total optical density at the microinvasion might suggest the emergence of one or two clones that can be responsible for the invasive phenotype.

Adenocarcinoma↗
PubMed1999

Chemotaxis: the proper physiological response to evaluate phylogeny of signal molecules.

In this review we summarize our results gained on the investigations focused to characterize ligand and signaling mechanisms required for the chemotaxis in the unicellular model Tetrahymena. Our data show that short chain signal molecules (amino acids, oligopeptides) are distinguished upon their physicochemical characteristics - lipophilicity, residual volumes and statistical distribution of side-chain distances (e.g. in proline containing dipeptides), while the vertebrate hormones have also specific attractant or repellent effects in the model (FSH vs. TSH). Hormonal imprinting developed by pretreatments has also special, signal molecule dependent effect (histamine vs. serotonin). It is shown that "chemotactic selection" of cells, by the new probe developed by us is a suitable tool to provide subpopulations possessing enhanced chemotactic receptor-effector mechanisms with respect to the selector signal molecules (IL-8, TNF-alpha).

Amino Acids↗
PubMedDate not supplied

[Vitamin B 6 metabolism in phenylketonuria].

Based on the analysis of the dependence of 4-pyridoxic acid urinary excretion from pyridoxal-5'-phosphate blood plasma level and its statistic distribution it has been shown that vitamin B-6 metabolism in children suffering from phenylketonuria and therefore the criteria of the body saturation with this vitamin differ from those for healthy people. Increased pyridoxal-5'-phosphate blood plasma level has been demonstrated for PKU children. The concentration of 11 ng/ml should be considered as a bottom border of the adequate supply with vitamin B-6. The elevated vitamin B-2 intake approximates vitamin B-6 status indexes of sick children to those usually measured in healthy children. The necessity for the reevaluation of vitamin B-2 and B-6 optimal diet content under this disease and its biochemical validation are discussed.

Child↗
PubMed2000

[Hospitalization for renal colic in the emergency room of a large central hospital in Israel: epidemiological features and clinical manifestations].

The medical records of all patients referred to the emergency department (ED) of Sheba Medical Center for renal colic during 1996 were analyzed. Patients discharged from the ED and those hospitalized were compared. There was no significant difference between the 2 groups with regard to average age or sex distribution. Statistically significant differences were found with regard to frequency of chills and fever, history of renal colic, referral for renal colic during that year or hospitalization for renal colic or nephrolithiasis, previous positive imaging, stone removal by surgery or extracorporeal shock wave lithotripsy, fever exceeding 37.5 degrees and administration of fluids, pethidine or pramin in the ED, prolonged stay in the ED and previous appendectomy. A conditional regression model tested the predictive value of each of those factors. Inclusion of independent variables into the model led to an overall correct classification rate of 84.43%, with 44.83% sensitivity and 93.16% specificity. There were correlations between referrals for renal colic, overall renal colic rate and average monthly temperature, so there was no pure correlation between average monthly temperature and referrals to the ED for renal colic. The major indications for hospitalization were actually the clinical ones, indicating either an active metabolic disease or suspected obstruction of the urinary tract. Treatment in the ED and duration of the visit indicated disease severity.

Adult↗
PubMedDate not supplied

[Color categorization and the structure of perceptive color].

This paper is an attempt to develop a coherent framework for understanding, simulating, and predicting color categories. The process of color categorization can be understood as a structuring of preceding color experience on the basis of statistical distribution of light in observers environment. A proposed computational model of color categorization includes: 1) distribution of R, G, B pixel values representing a sample of 630 color images of natural scenes (analogue of physical light experience); 2) transformation of the R, G, B pixel values into L*u*v* coordinates of the CIELUV color space (analogue of the process of color perception); 3) distribution of the L*u*v* coordinates representing the sample of the color images (analogue of perceived color experience); 4) k-means clustering algorithm of the L*u*v* coordinates representing the sample of the color images (analogue of the process of color categorization); 5) location and order of color clusters (analogue of location and order of color categories). The proposed computational model enables us to predict the location and order of color categories, being consistent with psycholinguistic data.

Algorithms↗
PubMed1998

Graded Autocatalysis Replication Domain (GARD): kinetic analysis of self-replication in mutually catalytic sets.

A Graded Autocatalysis Replication Domain (GARD) model is proposed, which provides a rigorous kinetic analysis of simple chemical sets that manifest mutual catalysis. It is shown that catalytic closure can sustain self replication up to a critical dilution rate, lambda c, related to the graded extent of mutual catalysis. We explore the behavior of vesicles containing GARD species whose mutual catalysis is governed by a previously published statistical distribution. In the population thus generated, some GARD vesicles display a significantly higher replication efficiency than most others. GARD thus represents a simple model for primordial chemical selection of mutually catalytic sets.

Catalysis↗
PubMed2001

Molecular identification using flow cytometry histograms and information theory.

Flow cytometry is a common technique for quantitatively measuring the expression of individual molecules on cells. The molecular expression is represented by a frequency histogram of fluorescence intensity. For flow cytometry to be used as a knowledge discovery tool to identify unknown molecules, histogram comparison is a major limitation. Many traditional comparison methods do not provide adequate assessment of histogram similarity and molecular relatedness. We have explored a new approach applying information theory to histogram comparison, and tested it with histograms from 14 antibodies over 3 cell types. The information theory approach was able to improve over traditional methods by recognizing various non-random correlations between histograms in addition to similarity and providing a quantitative assessment of similarity beyond hypothesis testing of identity.

Animals↗
PubMed1979

[Ultradian (between 5 and 70 minutes) respiratory (VO2, VCO2) rhythms of 4 small vertebrates used in biomedical research].

Four laboratory Vertebrate species with a predominant activity, either diurnal (Coturnix coturnix japonica), nocturnal (Rattus norvegicus, Mus musculus), or equivocal (Cavia porcellus), present, in usual housing conditions (temperature 20 degrees C, hygrometry 60-70%, acoustical background 70 dB, LD12:12 lighting L = 150 lx), food and water ad libitum, ultradian respiratory (VO2, VCO2) rhythms of short periods. The frequencies of these rhythms are independent of food intake and activity variations correlated to the lighting phase and regimen (LD, LL). The period (tau) of these ultradian respiratory rhythms is in isolated animals, between 5 and 70 min., according to the species studied. Grouping of several individuals of a same species, in a ventilated chamber, modifies the statistical distribution of the periods of the ultradian rhythms, but does not change the interspecies differences.

Animals↗
PubMed1975

Impulse activity of a single motor unit upon the rhythm of the summated muscle activity.

The impulses of single motor units (MUs) are recorded using the method of selective leading off with surface bipolar electrodes with small interpolar distance. Parallel recording is made of the summated EMG and of its apparatus-transformed form-the mean voltage curve of the EMG. The correct position of the electrodes with regard to the MU is controlled by means of a vector-electromyographic (VEMG) method. The statistical parameters of the impulse series of the individual MUs and of the groups of impulses in the summated EMG are determined, as well as the time interrelations between the impulses of the selected MUs and the groups of impulses in the mean voltage curve of the EMG. The delay in the appearance of the impulses from the selected MUs with regard to the beginning of the group of impulses, proved a statistically distributed value according to a bimodal type which becomes more pronounced upon rating to the intervals.

Electrodes↗
PubMed1975

Community noise criteria.

In the fields of community noise abatement and municipal planning, there are new requirements to define an environment of varying noise level by a single number rating method that correlates well with the subjective response of human beings. Typical criteria, either in use of proposed, are LN numbers (noise levels exceeded N% of the time), Leq (the equivalent sound level in dB(A) ), LNP (the Noise Pollution Level), and Ldn (the day-night average sound level in dB(A) ). Instruments available include an environmental noise classifier, a statistical distribution analyzer/recorder combination, and a digital sampling system for field measurements for subsequent interrogation by a programmable calculator.

City Planning↗