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Psychophysical researchers often need to vary stimuli parametrically during experimental design. The X Portable Interface Package, a set of free software libraries for X-Windows, provides a suitable platform for quickly prototyping visual stimuli and administering simple experiments.
BACKGROUND: Systematic reviews (SRs) must be of high quality. The purpose of our research was to compare the methodological and reporting quality of original versus updated Cochrane SRs to determine whether updating had improved these two quality dimensions. METHODS: We identified updated Cochrane SRs published in issue 4, 2002 of the Cochrane Library. We assessed the updated and original versions of the SRs using two instruments: the 10 item enhanced Overview Quality Assessment Questionnaire (OQAQ), and an 18-item reporting quality checklist and flow chart based upon the Quality of Reporting of Meta-analyses (QUOROM) statement. At least two reviewers extracted data and assessed quality. We calculated the percentage (with a 95% confidence interval) of 'yes' answers to each question. We calculated mean differences in percentage, 95% confidence intervals and p-values for each of the individual items and the overall methodological quality score of the updated and pre-updated versions using OQAQ. RESULTS: We assessed 53 SRs. There was no significant improvement in the global quality score of the OQAQ (mean difference 0.11 (-0.28; 0.70 p = 0.52)). Updated reviews showed a significant improvement of 18.9 (7.2; 30.6 p < .01) on the OQAQ item assessing whether the conclusions drawn by the author(s) were supported by the data and/or analysis presented in the SR. The QUOROM statement showed that the quality of reporting of Cochrane reviews improved in some areas with updating. Improvements were seen on the items relating to data sources reported in the abstract, with a significant difference of 17.0 (9.8; 28.7 p = 0.01), review methods, reported in the abstract 35 (24.1; 49.1 p = 0.00), searching methods 18.9 (9.7; 31.6 p = 0.01), and data abstraction 18.9 (11.7; 30.9 p = 0.00). CONCLUSION: The overall quality of Cochrane SRs is fair-to-good. Although reporting quality improved on certain individual items there was no overall improvement seen with updating and methodological quality remained unchanged. Further improvement of quality of reporting is possible. There is room for improvement of methodological quality as well. Authors updating reviews should address identified methodological or reporting weaknesses. We recommend to give full attention to both quality domains when updating SRs.
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This paper presents an ultrasonic blood densitometer for dynamic measuring blood density. Compared with traditional blood densitometer, the ultrasonic blood densitometer has the advantages of high precision, fast response and little sample etc.
A kind of amplifier and data aquisition method is introduced in this paper. In this method, signals of various kinds of ions in different specimen are converted skillfully. The experiment results showed that the virtues of this circuit are high in impendance, simple in structure and accurate in surveying, etc.
A new respiration monitor was developed with this paper, which can monitor tidal volume continuously based on the impedance technique as well ad ECG at the same time. Advanced digital storage display technique and modular hardware design are adopted in this system. One by one calibration method was introduced to solve problem of individual differences in the measurement of tidal volume, which make it viable to monitor Tidal volume with impedance technique. The system possesses characteristic of high ratio of performance to cost. Clinical tests of the system have been made for nonsurgical patients, the results show that the system meets the basic clinical requirements, and its wide clinical applications are expected in the future.
A new three dimensional testing and analysing system of dental model is discussed It is designed based on the motion theory of robots. The system is capable of not only measuring the three dimensional sizes of dental models, but also saving and outputing the tested data. The construction of the system is briefly introduced here.
A single-channel ECG telemetry system with infrared rays as the medium was designed. It can be used to monitor the subject's ECG in real-time. This system has functions of detecting abnormal ECG, alarming, dieplaying, storing and printing. It is a beneficial attempt in the clinical application of the infrared telemetry.
The Developments of the Hospital Plate Washer and its control system are introduced in the paper, and the application of the ultrasound technotology in the plate washer is described too.
A coupling principle of reflecting impedance based on resonance is designed to achieve impedance detection with high sensitivity. It is characterized by small impelled current, high sensitivity and simple circuit. The principle can be used not only in detecting human respiratory impedance, but also in detecting the bio-impedance of other human organs. It may find wide application in this aspect.
The design of PACS image workstation based on DICOM3.0 is introduced in the paper, then the designing method of the PACS image browser based on the control system theory is presented,focusing on two main units:DICOM analyzer and the information mapping transformer.
Infrared radiations are widely used in medical therapeutics. It has been argued that the doses and the periods of time employed in experimental animals are higher than those used in clinic. Thus, we considered of interest to analyse aspects of dosimetry and thermic effects of infrared rays with current methods in medical practice, using the in ovo chick embryo as a model of easy control. To this end we designed a system to measure temperatures and their acquisitions and software for its handling. The system consists of: a) thermic points: thermocuples or termistores adaptable to the experimental requirements and calibrated with a greater precision within a range of ten degrees around the incubation temperature; b) acquirer circuit of thermic data (hardware): it generates a time base that varies with the thermic sensor. Software: the PC XT or AT detects changes in the time base by means of a programs' in a Turbo Pascal; c) storage and analysis of data allows, through a menu (expansibles) the scale selection, time of program data to be acquired, storage and recovery of the diskette information and graphic impression; d) chick's embryonated eggs. This system allows to measure temperature distribution in small physical spaces with little disturbance of the system to be measured in irradiated bodies, to analyse variations of the temperatures in time and to secure a greater confidence and automatism to obtain the required data.
This paper introduces the development of hematomanometer auto test instrument of a news measurement standard. The hard-ware and soft-ware and the circuit structure of it are described in detail.
The practice of acupuncture involves the stimulation of specific points on the skin called 'acupuncture points' which are small regions of local or referred pain that are more sensitive than surrounding tissue. The fact that acupuncture points can be identified subjectively as tender points and are found to have characteristic electrical properties suggest that they are functional entities rather than structural ones. These functional properties are used diagnostically in a clinical setting as pathology in a particular body location has been shown to correlate with increased tenderness and electrical conductivity of the 'corresponding' acupuncture point using electronic 'point locators', which measure the DC resistance of points compared to surrounding skin. Commercially available point locators generally utilize a metal locator probe and an indifferent electrode and are designed to produce an auditory output (usually a high pitched tone) when a point is located. These devices however, are open to criticism. They are unable to control for local variations in skin thickness, surface secretions, or pressure placed on the electrode, and are only able to measure a single point at a time. These make them time consuming to use and subjective to user bias in point selection. Furthermore these devices do not store data and are therefore unsuitable for producing a map of skin resistance, which can be accessed over time. To overcome some of the limitations of currently available single probe devices, we have designed a multi-channel probe capable of measuring and then mapping the skin resistance of multiple points.
Ergonomics is the practical and scientific study of people in relation to their working environment. We describe its application to the operation of a trauma resuscitation room. We used specifically designed computer software. This methodology enables a unique and objective assessment of the design and operation of a clinical system. It may be particularly applicable to other hospital areas where the efficient interaction of staff, patients and equipment is crucial to the optimal clinical outcome.
The software requirements specification is the single most important document in the software development process. It provides the basis for development as well as for validation. The SRS needs to include adequate definition of all requirements without specifying implementation or project management issues. The SRS should be completed early in the development process. However, it is very likely that changes will occur during the development life cycle. This is not an excuse for approving and releasing the current version of the SRS. When changes occur, the SRS must be revised. In any case, the concept is to deal with the current, approved version of the SRS. Ultimately, the SRS should include all the information needed to proceed into the design phase of software development.
Although planar radionuclide techniques provide accurate, noninvasive measurements of myocardial perfusion and function that are of proven clinical value in the evaluation of the cardiac patient, they are limited by poor object contrast and superimposition of surrounding structures. Due to incomplete angular sampling and significant longitudinal distortion, limited angle tomography did not solve these problems. Single photon emission computed tomography (SPECT) can acquire scintillation information over very small angles of rotation and, thus, improve both object contrast and delineation of overlying or adjacent structures without distortion. The early SPECT systems were cumbersome, dependent on individual user developed software, and had extremely long acquisition and processing time. Improved camera design, new software algorithms, and the use of array processors have simplified and standardized quality control, decreased processing time, and minimized the number of user interventions. New image display formats and quantitative methods of analysis have made interpretation less cumbersome, more reliable and highly reproducible. Cardiac SPECT has been used with thallium-201 and gated blood pool imaging in both research and clinical applications and shown an improvement over planar methods of acquisition.
Porous hydroxyapatite (HA) has been used as a bone graft material in the clinics for decades. Traditionally, the pores in these HAs are either obtained from the coralline exoskeletal patterns or from the embedded organic particles in the starting HA powder. Both processes offer very limited control on the pore structure. A new method for manufacturing porous HA with designed pore channels has been developed. This method is essentially a lost-mold technique with negative molds made with Stereolithography and a highly loaded curable HA suspension as the ceramic carrier. Implants with designed channels and connection patterns were first generated from a Computer-Aided-Design (CAD) software and Computer Tomography (CT) data. The negative images of the designs were used to build the molds on a stereolithography apparatus with epoxy resins. A 40 vol% HA suspension in propoxylated neopentyl glycol diacrylate (PNPGDA) and iso-bornyl acrylate (IBA) was formulated. HA suspension was cast into the epoxy molds and cured into solid at 85 degrees C. The molds and acrylate binders were removed by pyrolysis, followed by HA green body sintering. With this method, implants with six different channel designs were built successfully and the designed channels were reproduced in the sintered HA implants. The channels created in the sintered HA implants were between 366 microm and 968 microm in diameter with standard deviations of 50 microm or less. The porosity created by the channels were between 26% and 52%. The results show that HA implants with designed connection pattern and well controlled channel size can be built with the technique developed in this study.