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The CellSoft computerized semen analysis system. II. On the optimalization of running conditions concerning gray scale and cell size range.

The CellSoft automated semen analysis system was studied concerning the effect of gray scale (GSc) variation on cell motion parameters and to establish an appropriate setting for human spermatozoal sizes (PixMin and PixMax) based on the cell's instant velocities (InsVels). GSc could be set within a range from "optimum" till +10 units without, except for curvilinear velocity, the CellSoft generated sperm measures being altered (p greater than 0.05). The aspect of a sample specific GSc setting according to certain criteria is stressed. Considering the area of immobilized spermatozoa (at GSc + 20) and of motile cells with low InsVel, PixMin should be set at 3 pixels. Correspondingly, the InsVel determined setting for PixMax (at a maximum velocity threshold set at 200 microns/sec.) was 28 pixels. A final recommendation on the setting for cell sizes can, however, only be determined in considering sizes of nonsperm seminal elements and in studying the appropriate setting for the maximum velocity threshold.

Computer Systems↗

[Establishment of three-dimensional finite element models by using a series of plane section images processed with an image analysis system].

The geometric similarity and mesh dividing of finite element models directly create an effect on the results of analysis when a theoretical stress analysis is performed by the use of finite element method. The model is routinely established by means of sectioning the specimen. In this paper, a series of plane section CT images of the teeth and mandible, an image analysis system and a specially designed software for modeling three-dimensional finite element were used to establish a three-dimensional finite element model. It is a new preprocessing method for finite element applications in the field of oral biomechanism. The technique is characterized by the advantages of high similarity of the model to specimens and no damage to specimens; it is simple and easy. The images and figures can be repetitively used.

Biomechanical Phenomena↗

Technical report. An inexpensive densitometric analysis system using a Macintosh computer and a desktop scanner.

A brief description of the setup of an inexpensive densitometric analysis system is provided. This system uses a software package and scanner that can be obtained for a total of less than $1000 and that can be operated by any Macintosh computer, including a MacPlus. In the event that a scanner is already available, the software itself can be obtained for approximately $399. Several comparisons are presented of data obtained with this system, data obtained by other analytical methods and data obtained with more expensive, dedicated densitometric systems. These comparisons demonstrate the usefulness and accuracy of this system.

Computers↗

Contributions of social medicine and systems analysis to formulating objectives for a community-based cancer prevention programme.

In the part of Stockholm Cancer Prevention Programme, that is focussing on diet and cancer, the contribution of social medicine has been based on its concern for the relationships between individuals, populations, the environment and the socio-political structure. This has led to the choice of the community intervention approach, based on geographically defined populations, and involving the participation of organisations already active within the relevant areas. The contribution of systems analysis has been based on its concern for explicit models of the processes of cause and effect that lead from intervention to outcome, as a basis for debate and common understanding among the various participants. The combination of the two approaches has helped to clarify the objectives and has shaped the planned pattern of intervention.

Community Health Services↗

Determination of microsatellite repeats in the human thyroid peroxidase (TPOX) gene using an automated gene analysis system with nanoscale engineered biomagnetite.

The number of repeat in the microsatellite region (AATG)(5-14) of the human thyroid peroxidase gene (TOPX) was determined using an automated DNA analysis system with nano-scale engineered biomagnetite. Thermal melting curve analysis of DNA duplexes on biomagnetite indicated that shorter repeat sequences (less than 9 repeats) were easily discriminated. However, it was difficult to determine the number of repeats at more than nine. In order to improve the selectivity of this method for the longer repeats, a "double probe hybridization assay" was performed in which an intermediate probe was used to replace a target repeat sequence having more than 9 repeats with a shorter sequence possessing less than 9 repeats. Thermal probe melting curve analyses and Tm determination confirmed that the target with 10 repeats was converted to 5 repeats, 11 repeats converted to 4 and 12 to 3, respectively. Furthermore, rapid determination of repeat numbers was possible by measuring fluorescence intensities obtained by probe dissociation at 56 and 66 degrees C, and 40, 60 and 80 degrees C for signal normalization.

Ferrosoferric Oxide↗

Dynamic systems analysis for better hospital bed operation: using time series model.

Achieving high efficiency in hospital bed operations becomes an important aim of hospital management, as managerial environment of hospitals has been increasingly competitive in Korea. Many authors have made studies on higher occupancies, but very few about systems characteristics of the time serial data as well as decision behavior on bed operations. For those topics overlooked, this paper applies Wu's Dynamic Data Systems Analysis, for which an ARMA model is developed and its characteristic roots are analyzed. The results include such information as periodic nature of data, strength and effects of disturbances, based on which interpretations are provided tuned to the target system's operational aspects. For this work, data were collected and processed for two different periods of time, October 1990 to April 1991 and October 1993 to April 1994. While the average occupancies between two periods are not statistically different, the effect of error disturbances was managed better in 1990 than in 1993. And the restoring forces from fluctuations are almost the same between the periods of comparison. With this analysis, conclusions are summarized: in both periods, short-term flexibility in patient admissions and discharges are good, but long-term management of hospital census trend needs to be improved by developing the system of controlling patient admissions and discharges. For the improvement, some possible approaches are suggested for future studies.

Appointments and Schedules↗

System analysis of Phycomyces light-growth response with Gaussian white-noise test stimuli.

The light-growth response of the Phycomyces sporangiophore is a transient change of elongation rate in response to changes in ambient blue-light intensity. The white-noise method of nonlinear system identification (Wiener-Lee-Schetzen theory) has been applied to this response, and the results have been interpreted by system analysis methods in the frequency domain. Experiments were performed on the Phycomyces tracking machine. Gaussian white-noise stimulus patterns were applied to the logarithm of the light intensity. The log-mean intensity of the broad-band blue illumination was 0.1 Wm-2 and the standard deviation of the Gaussian white-noise was 0.58 decades. The results, in the form of temporal functions called Wiener kernels, represent the input-output relation of the light-growth response system. The transfer function, which was obtained as the Fourier transform of the first-order kernel, was analyzed in the frequency domain in terms of a dynamic model that consisted of a first-order high-pass filter, two second-order low-pass filters, a delay element, and a gain factor. Parameters in the model (cutoff frequencies, damping coefficients, latency, and gain constant) were evaluated by nonlinear least-squares methods applied to the complex-valued transfer function. Analysis of the second-order kernel in the frequency domain suggests that the residual nonlinearity of the system lies close to the input.

Light↗

Intracranial fluid dynamics in normal and hydrocephalic states: systems analysis with phase-contrast magnetic resonance imaging.

OBJECTIVE: To present a novel magnetic resonance (MR) method of analysis of cerebrospinal fluid (CSF) flow dynamics. METHODS: Fifty-one subjects were explored with phase-contrast cine MR imaging. There were 36 volunteers, 9 patients with normal pressure hydrocephalus (NPH), and 6 patients with asymptomatic ventricular dilation (VD). The transfer function XFRA/CSF from the arterial pulse waves (APWs) and the CSF pulse waves (CSFPWs) and the transfer function XFRCSF/SS from the CSF pulse waves (CSFPWs) and the sagittal sinus pulse waves (SSPWs) were studied separately. RESULTS: There was a significant difference in the amplitude spectrum of the XFRA/CSF of patients with VD and volunteers (P < 0.05) and in that of patients with NPH and volunteers (P = 0.005). The amplitude of the fundamental frequency was higher in the NPH group than in the VD group (P = 0.02). In patients with NPH, the amplitude spectrum of XFRCSF/SS showed an attenuation of the pulse wave components that significantly differed from the observed amplification in healthy subjects (P = 0.009) and patients with VD (P = 0.012). CONCLUSION: This systems analysis method could help to detect increased venous compliance in VD and decreased venous compliance in NPH.

Adult↗

Anthropomorphic models for checking the calibration of whole-body counters and activation analysis systems.

Three models of the human body have been made for checking the calibration of whole-body counters and activation analysis systems. Their weights are 41, 67 and 110 kg. Each contains simplified forms of lungs, bones, thyroid, kidneys and liver and has a chemical composition similar to that of the ICRP standard man. In addition traces of toxic elements such as Cd and Hg have been included in various organs. The composition of the manikins has been measured at four centres where activation analysis in vivo has been carried out. The potassium contents have been measured at three other centres. Differences between measured and actual contents have often been much larger than quoted uncertainties of the measurements, 20-50% for Na, Cl and P. For K, differences did not exceed 17% but are still often greater than the expected uncertainty. The greatest errors usually occurred with the smallest manikin.

Activation Analysis↗

Development of multicolour digital image analysis system to enumerate actively respiring bacteria in natural river water.

AIMS: To develop a rapid and simple method for the assessment of metabolic activity of bacteria in natural environment. METHODS AND RESULTS: A rapid and simple multicolour digital image analysis system for enumerating viable bacteria based on active fluorescent staining has been developed. This system can accurately differentiate actively respiring bacteria and non-respiring bacteria by distinctive colour information in the digital image captured by an epifluorescence microscope equipped with low magnification objective lens. An algorithm to distinguish bacteria from considerable detritus, which produced bright fluorescence in different colours, by colour segmentation has also been developed. This system was applied to river water samples, and the total and respiratory active bacterial counts by digital image analysis were highly related to those by epifluorescence microscopy (r2 = 0.96 and 0.93, respectively). CONCLUSION: This system allowed the rapid and simple differentiation of bacteria from detritus and concurrent assessment of their metabolic activity, with results being available within 1 h. SIGNIFICANCE AND IMPACT OF THE STUDY: The low magnification image analysis allows more rapid and simple quantification of bacteria and could considerably decrease image data amount and acquisition time. This system could be easily applied to the rapid analysis of microbes in various environments.

Algorithms↗

A flow injection analysis system involving immobilized NADH oxidase in column form for clinical analysis.

A highly sensitive FIA system for chemiluminometric determination of reduced coenzyme, NADH, was developed, using immobilized NADH oxidase from Brevibacterium ammoniagenes. The enzyme catalyzed the oxidation of NADH generating hydrogen peroxide which emitted chemiluminescence when mixed with luminol and potassium ferricyanide. The immobilized enzyme reactor was a mini-column, measuring 1 or 2 mm in inner diameter and 20 mm in length, and the sample volume was only 1 microliter per assay, with a feeding speed of one sample per min and a lowest detection limit of 10 pmol NADH. A FIA system was also developed for the determination of magnesium in human serum, using an enzyme column reactor with simultaneously coimmobilized hexokinase, D-glucose-6-phosphate dehydrogenase, and NADH oxidase. The performance of the system was as satisfactory as a routine colorimetric assay, but with much higher sensitivity.

Colorimetry↗

The CellSoft computerized semen analysis system: sperm image sizes and velocity measurements, and the consequences for internal running conditions.

The CellSoft computer-assisted sperm analysis system was evaluated as to the optimal setting of three components of the internal running conditions. These 'set up' parameters were the lower setting for cell size range (PIXMIN), threshold velocity (MINVEL) and maximum velocity (MAXVEL). The decision for the PIXMIN setting was founded on observed sizes of sperm with low instant velocities combined with a study of the relationship between false positive observations for sperm and the PIXMIN setting. Our recommendation for this setting is three pixels. From the observation that 97.5% of immobilized sperm exhibit instant velocities of less than 15 microns sec-1, this is our proposal for the MINVEL setting. Correspondingly, the 97.5 percentile for instantaneous velocities in a population of some 14,000 cells (30 men with type 'a' motility, WHO) was 168 microns sec-1. We recommend that MAXVEL be set at this limit. Alternative settings for both MINVEL and MAXVEL are presented as some users may wish to apply other percentiles. From the above results a setting for PIXMAX at 25 pixels could be inferred. We recommend that these settings be applied in semen laboratories analysing human native samples at room temperature.

Computers↗

Differential effects of nefazodone and cognitive behavioral analysis system of psychotherapy on insomnia associated with chronic forms of major depression.

BACKGROUND: The antidepressant nefazodone and the Cognitive Behavioral Analysis System of Psychotherapy (CBASP) were recently found to have significant, additive effects in a large multicenter study of chronic forms of major depression. As nefazodone-mediated blockade of serotonin-2 receptors may directly relieve insomnia associated with depression, we examined the more specific effects of CBASP and nefazodone, singly and in combination, on sleep disturbances. METHOD: A total of 597 chronically depressed outpatients (DSM-III-R criteria) with at least 1 insomnia symptom were randomly assigned to 12 weeks of treatment with nefazodone (mean final dose = 466 mg/day), CBASP (mean = 16.0 sessions), or the combination (mean dose = 460 mg/day plus a mean of 16.2 CBASP sessions). Continuous and categorical insomnia outcomes, derived from standard clinician- and self-rated assessments, were compared. RESULTS: Patients receiving nefazodone (either alone or in combination with CBASP) obtained significantly more rapid and greater ultimate improvement in insomnia ratings when compared with those treated with CBASP alone. This difference was maximal by the fourth week of therapy and sustained thereafter. Combined treatment did not result in markedly better insomnia scores than treatment with nefazodone alone on most measures, although patients receiving both CBASP and nefazodone were significantly more likely (p < .001) to achieve > or = 50% decrease in insomnia severity. CONCLUSION: Despite comparable antidepressant efficacy, monotherapy with nefazodone or CBASP resulted in markedly different effects on the magnitude and temporal course of insomnia symptoms associated with chronic forms of major depression. Patients receiving the combination of psychotherapy and pharmacotherapy benefited from both the larger and more rapid improvements in insomnia associated with nefazodone therapy and the later-emerging effects of CBASP on the overall depressive syndrome.

Adult↗

[Detection of apoptosis with gel eletrophoresis combined with computerized gel analysis system].

OBJECTIVE: To explore a new method for detecting cellular apoptosis. METHODS: Using routine electrophoresis assisted by computerized gel documentation analysis system(GDAS), apoptosis of the macrophages treated with dexamethasone was qualitatively and then quantitatively detected. RESULTS: Apoptosis occurred in the macrophages treated with dexamethasone, and DNA fragmentation of the apoptotic macrophages was visualized on 1% agarose gel electrophoresis. The apoptosis rates as determined by computerized GDAS were consistent with the results obtained from flow cytometry that showed typical apoptosis peak. CONCLUSION: Agarose gel electrophoresis assisted by computerized GDAS was relatively simple and less costly in qualitative and quantitative detection of apoptosis with precision.

Animals↗

Estimation of motility of subgingival microflora using high speed shutter camera and image analysis system.

This paper reports on the development of a motility measuring system for human subgingival microflora using a high speed shutter camera and an image analysis system. The paper first presents the method for estimating the motility of subgingival microflora by the total number of pixels and then describes the evaluation of the total number of pixels as an indicator of bacterial motility. Our results with this system demonstrate that the motility of subgingival microflora can be expressed as the total number of pixels.

Bacterial Physiological Phenomena↗

Modifying the Roter Interaction Analysis System to study provider-patient communication in telemedicine: promises, pitfalls, insights, and recommendations.

This paper suggests modifications to the Roter Interaction Analysis System (RIAS)--the most widely used measure for assessing provider-patient communication during conventional face-to-face consultations--for use in telemedicine. The RIAS, which describes and categorizes communication behaviors, is used to quantify communication events, which may then be correlated with patient, provider, and system attributes and health outcomes. Most of the changes suggested here add new coding subcategories to characterize technology-related utterances and to provide opportunities for global assessments of the overall technology environment within which provider-patient interactions took place. There are also general issues raised that interaction analysis researchers should consider when studying provider-patient communication in a telemedicine context. These relate to nonverbal behavior, multiple participants, missing information, and validity and reliability. In addition to comparing telemedicine to in person consultations, a modified RIAS could be used to compare televideo consultations to each other, across different specialties and technical specifications. A modified RIAS would accommodate not only differences in the current technology environment, but also changes in the way providers and patients communicate over time. The more we know about what interaction patterns lead to best outcomes, the more emphasis can be placed on developing training programs and other interventions to enhance patient-provider interactions in telemedicine.

Humans↗

[Reproducibility of measurement of intraocular lens location in situ with an anterior eye segment analysis system].

The reproducibility of the measurement (accuracy of repeated measurement) of intraocular lens (IOL) location in situ was studied using an anterior eye segment analysis system (NIDEK EAS-1000). The measurements were performed as follows: (1) errors at photography: 1) errors by the individual photographer 2) errors among three photographers. (2) errors at analysis: 1) errors by individual analysists 2) errors among six analysists. The greatest standard deviation was the accuracy of repeated measurement. Accuracy of repeated measurement (tilt and decentration) was (1) 1) 1.104 degrees, 0.083 mm, (1) 2) 0.866 degrees, 0.072 mm, (2) 1) 0.597 degrees, 0.079 mm, (2) 2) 0.562 degrees, 0.079 mm. From the data obtained in this study, the reproducibility of the EAS-1000 was satisfactory for measurement of IOL location.

Anterior Eye Segment↗