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At least 811 records · Page 45Linked to original sources
PubMed2003

Integrated bio-fluorescence sensor.

Due to the recent explosion in optoelectronics for telecommunication applications, novel optoelectronic sensing structures can now be realized. In this work, we explore the integration of optoelectronic components towards miniature and portable fluorescence sensors. The integration of these micro-fabricated sensors with microfluidics and capillary networks may reduce the cost and complexity of current research instruments and open up a world of new applications in portable biological analysis systems. A novel optoelectronic design that capitalizes on current vertical-cavity surface-emitting laser (VCSEL) technology is explored. Specifically, VCSELs, optical emission filters and PIN photodetectors are fabricated as part of a monolithically integrated near-infrared fluorescence detection system. High-performance lasers and photodetectors have been characterized and integrated to form a complete sensor. Experimental results show that sensor sensitivity is limited by laser background. The laser background is caused by spontaneous emission emitted from the side of the VCSEL excitation source. Laser background will limit sensitivity in most integrated sensing designs due to locating excitation sources and photodetectors in such close proximity, and methods are proposed to reduce the laser background in such designs so that practical fluorescent detection limits can be achieved.

Biosensing Techniques↗
PubMed1999

Participant satisfaction and comfort with multidisciplinary pediatric telemedicine consultations.

PURPOSE: The aim of this study was to measure both satisfaction and comfort levels and estimates of cost savings of families with children receiving health care services from a distant pediatric tertiary care center by readily available telecommunications technologies. METHODS: From February 1996 to September 1997, 140 children at a site 840 miles from the tertiary care center were seen during an evaluative trial of telemedicine consultations (TMC). The TMC visit was the initial encounter with the tertiary care specialist for 31 children. After consultation, each family was asked to complete an anonymous quality management survey that asked for estimates of cost savings and assessed their level of comfort and satisfaction with 13 other aspects of the TMC encounter. A 3- or 5-point Likert scale was used for each question. Comfort scores before and after each consultation were compared by chi2 analysis. Logistic regression was used to determine the independent predictors of satisfaction. RESULTS: 104 of the 140 (74%) families responded. Mean patient estimated cost savings was $1,318+/-677. The highest level of comfort was noted by 58% of respondents before TMC and by 77% after (P = .005). On a 5-point scale, 71% scored 5 (completely satisfied). None scored less than 3. The independent statistically significant predictors of satisfaction were concerns about privacy, comfort with the camera, and perceived specialist comfort. CONCLUSIONS: In addition to providing financial savings, TMC is well accepted by families and children. Those using this new technology must give special attention to issues of patient privacy, camera comfort, and specialist comfort.

Child↗
PubMed1993

Transtelephonic echocardiography: successful use in a tertiary pediatric referral center.

Recent advances in computers and telecommunications have made transtelephonic echocardiography practical. Our institution is developing a network of transmissional echocardiographic sites at several hospitals in our referral region. We reviewed our initial experience to determine whether transmissional echocardiographic studies (1) gave an appropriate diagnostic impression compared with subsequent videotape review and (2) led to appropriate clinical management (i.e., transfer to a tertiary center or continuation of local care and follow-up). From Aug. 1, 1991, to May 31, 1992, we evaluated 47 transmissional studies (diagnoses: 24 normal, 8 patent ductus arteriosus, 6 ventricular septal defect, 2 pulmonary stenosis, 1 ventricular septal defect with interrupted aortic arch, and 6 miscellaneous). Of 47 studies, 39 (83%) were thought to give accurate diagnostic impressions compared with videotape review. Most inaccuracies were due to the selection and transmission of inconclusive information in an otherwise accurate diagnostic study. Only 1 (2%) of 47 studies resulted in an inappropriate clinical decision; a patient's transfer for treatment of a potent ductus arteriosus was delayed 1 day because of an inconclusive transmissional study. We conclude that transmissional echocardiography is useful in the management of pediatric patients with suspected heart disease in a regional referral setting.

Echocardiography↗
PubMed1999

Hypersensitivity to electricity: working definition and additional characterization of the syndrome.

Those who believe that electric appliances trigger adverse symptoms have coined the label hypersensitivity to electricity. Scientific research has not been able to identify a direct link between electromagnetic fields and symptoms, and no diagnostic criteria exist. Groups with reported hypersensitivity are very heterogeneous. A need exists for an operational working definition and improved characterization of groups. We report an investigation of symptoms and risk indicators associated with reported hypersensitivity to electricity-based on a survey at a high-technology, multinational telecommunications corporation. Comparisons are also made with patients referred to a university department of occupational and environmental health. No association was found between specific psychosocial work characteristics nor personal traits and hypersensitivity to electricity. We present skin and neurovegetative symptom indices. Results indicate that skin, and not neurovegetative symptoms, characterize the syndrome, at least during the first years of illness. For characterization, we propose a set of dimensions, including triggering factors, behavior, and duration of symptoms.

Adult↗
PubMed1997

The lack of effects of nonthermal RF electromagnetic fields on the development of rat embryos grown in culture.

Rat embryos (9.5 days old) were exposed for up to 36 h to various radio frequency (RF) electric and magnetic fields (modulation frequency: 16, 60, 120 Hz; electric field strength: 60, 600 V/m; magnetic induction: 0.2, 2.0 microT). A resonator technique was used to generate standing waves thus fulfilling three conditions: The site of maximum electric and magnetic oscillations could be separated, the field strengths were known exactly and a high homogeneity over the sample volume was achieved. In each frequency region the transmitter power levels were set to give specific absorption rate (SAR) values spreading from far below to far above the values met in the field of telecommunication (0.2, 1.0 and 5.0 W/kg). The criteria used to examine the embryos on day 11.5 for possible structural effects consisted of a scoring system, photographs, histology using both light and electron microscopy and determination of the protein content. All these data have been taken as sets of different intermediate frequency (IF) amplitude modulation of the RF carriers. Neither the electric nor the magnetic fields tested interfered significantly with the normal growth and differentiation of the embryos in vitro.

Animals↗
PubMed2003

Robotic renal and adrenal surgery.

Technology today is evolving at a dramatic rate. Quantum development has occurred in the area of robotic enhancement technology (RET) in the last decade. Incorporation of RET with advanced telecommunication technologies is a recent integration in medicine, with growth potential and application in the delivery of modern health care. There remain, however, many areas which need to be further improved and evaluated before clinical applications of the robot become accepted in adrenal and renal minimally invasive surgery.

Adrenal Gland Diseases↗
PubMed1997

Color images in telepathology: how many colors do we need?

It is generally assumed that for telepathology, accurate depiction of microscopic images requires the use of "true color" (ie, 24 bits, eight bits each for red, green, and blue) in the digitized image used for transmission. If such a 24-bit color image file, which provides a palette of 16.7 million colors, could be reduced in size by decreasing the possible numbers of colors displayed in the image to 8 bits (palette of 256 colors), the image files would require less storage space, could be transmitted more rapidly, and would require less telecommunications bandwidth. However, such color reduction must not result in detectable image degradation, especially if the images are to be used for diagnosis. Therefore, we performed a carefully controlled study to determine whether pathologists could detect differences in the quality of microscopic images that were reduced from 24 to 8 bits of color. Thirty pathologists were each asked to view a set of 30 image pairs displayed on a computer monitor. Each image pair consisted of the original 24-bit color version and an 8-bit color-reduced version, derived using an adaptive color reduction algorithm with diffusion dithering. Observers were asked whether they could detect any difference in quality between the image pairs. Then, regardless of their answer, they were asked to choose the better quality image of the pair. Overall, there was not a statistically significant ability to consciously detect differences between the image pairs (P < .750). However, when forced to choose, there was a significant preference for the 8-bit images as being of "better quality" (P < .005). We conclude that telepathology applications may be able to take advantage of adaptive color reduction algorithms to reduce image file size without sacrificing image quality. Additional studies must be performed to determine the minimal image requirements for accurate diagnosis by telepatholgy.

Color↗
PubMed1998

Remote operative urology using a surgical telemanipulator system: preliminary observations.

OBJECTIVES: A prototype surgical telemanipulator system was evaluated to determine the feasibility of remotely performing operative urology. METHODS: Surgeons operated remotely on anesthetized swine (n = 4), using a four degree-of-freedom teleoperator system. A stereoscopic video display of the remote surgical field guided tissue manipulation, which was performed using standard instrument tips attached to robotic arms. Nephrectomies, cystotomy closures, and ureteral anastomoses were performed by surgeons linked only by electronic cables to the remote operative field (5 m away). Flexible fiberoptic endoscopy was performed remotely, as well, using a simulated ureter in an ex vivo testing apparatus. The endoscope was positioned and manipulated remotely, and was maneuvered through a 25-cm-long tube. RESULTS: All procedures were completed successfully, demonstrating the capability to remotely incise, dissect, suture, and ligate tissues. Operative times were prolonged; however, the surgical telemanipulator was precise and accurate. Surgeons guided a flexible fiberoptic endoscope by remote observation and manipulation through 5-mm-diameter simulated ureters. There were no operative complications. CONCLUSIONS: Telesurgical manipulation is feasible in a controlled, experimental environment. All critical tasks performed by surgeons can be completed remotely, although performance must be improved substantially before telemanipulators enter the clinical armamentarium. Major hurdles remain in identifying clinical needs, improving performance and safety, and developing telecommunications capabilities that will enable telesurgical systems to achieve regulatory approval and acceptance.

Animals↗
PubMedDate not supplied

Midwifery education models. A contemporary review.

Midwifery education has a rich tradition of blending innovation with educational methods that have demonstrated their value to the profession. Examples of innovations that have influenced midwifery education include the use of the asynchronous modular system, the development of distance methodologies, and most recently the use of computer and telecommunications technologies to mediate education. This study was designed to explore trends in approaches to the education of midwives in both traditional and distance education programs. Program directors were surveyed and interviewed to assess their degree of instructional synchrony, their use of distance modalities, and their predominate methods of curriculum presentation. Results of the survey suggest that programs are using a variety of these approaches to educate their students. Decisions to integrate new educational technologies appear to be based on institutional values, community resources, and student needs.

Education, Nursing, Graduate↗
PubMed1998

Robotic surgery in urology.

The demand for improved surgical performance and reduced health care costs have led to the evaluation of surgical robotic systems. Robotic devices to assist urologists with transurethral resection of the prostate, percutaneous renal access, and laparoscopy are currently in development or are already in clinical use. The rapid advances made in telecommunication technology also have allowed for the development of telesurgical systems that permit surgeons to participate in surgery from a remote location. In the twenty-first century, surgical robots will be efficient, invaluable, and safe adjuncts to urologic practice.

Humans↗
PubMedDate not supplied

Following the water, the new program for Mars exploration.

In the wake of the loss of Mars Climate Orbiter and Mars Polar Lander in late 1999, NASA embarked on a major review of the failures and subsequently restructured all aspects of what was then called the Mars Surveyor Program--now renamed the Mars Exploration Program. This paper presents the process and results of this reexamination and defines a new approach which we have called "Program System Engineering". Emphasis is given to the scientific, technological, and programmatic strategies that were used to shape the new Program. A scientific approach known as "follow the water" is described, as is an exploration strategy we have called "seek--in situ--sample". An overview of the mission queue from continuing Mars Global Surveyor through a possible Mars Sample Return Mission launch in 2011 is provided. In addition, key proposed international collaborations, especially those between NASA, CNES and ASI are outlined, as is an approach for a robust telecommunications infrastructure.

Equipment Design↗
PubMed2004

The commercial development of space: is an international regulatory framework needed?

The commercial space sector to date has failed to develop comprehensive regulations--"rules of the road"--for its international activities. Within the next 5 years, conflicts with respect to international trade in satellite sales and launch services could emerge, highlighting the need for such a regulatory framework. If the commercial space sector is to continue to develop, it is important to begin discussions now, before these conflicts become significant, on the elements of an appropriate international regulatory framework. The existing framework for space activities was developed when government, not commercial, space activities were dominant, or was adapted from regulations in other sectors such as terrestrial telecommunications.

Aviation↗
PubMed1999

A survey of the accessibility of chiropractic clinics to the disabled.

OBJECTIVE: To determine to what degree chiropractic clinics are complying with the Americans with Disabilities Act (ADA), which mandates that health care clinics be accessible to the disabled. METHODS: A survey was developed and mailed to 200 chiropractic clinics in Orange and Los Angeles counties. The survey asked about the essential necessities for health care clinics to be accessible to the wheelchair-bound, the blind, and the deaf. It also sought to discover how many disabled patients these clinics were treating and the attitudes of practitioners and staff toward this population. RESULTS: The response rate was 50.5%. Accessibility for the wheelchair-bound was high. Accessibility for the blind was limited by a lack of Braille signs. Accessibility to the deaf was limited by lack of telecommunications device for the deaf or use of sign language interpreters. Most clinics were treating few or no disabled patients and did not perceive a need to become more accessible. CONCLUSION: There appears to be poor compliance with the ADA in chiropractic clinics in Los Angeles and Orange counties. Although data are lacking, it appears likely that the disabled population is being underserved by the chiropractic profession. Education for chiropractors on the rights and needs of the disabled population is necessary to give this group equal access to chiropractic health care.

Attitude of Health Personnel↗
PubMed2000

Strabismus examination by telemedicine.

OBJECTIVE: To evaluate the reliability of strabismus assessment using telemedicine (TM) technology. DESIGN: Two prospective interobserver agreement studies. One study compared the agreement between a standard and a TM examination, whereas the other assessed agreement between two independent standard examinations. PARTICIPANTS: Strabismus patients over 4 years of age examined at a remote community clinic and patients assessed in a strabismologist's urban practice. METHODS: Forty-two patients were examined in person by a pediatric ophthalmologist at the remote community and independently by a pediatric ophthalmology fellow by means of TM (TM-standard study). The TM examination was performed with the help of a qualified ophthalmic assistant at the remote telecommunication center using a Power Cam 100 camera, a Picture Tel Concorde 4500 teleconferencing system, and a 224 kilobyte bandwidth. For comparison, independent in person examinations were performed on 43 patients by both examiners (standard-standard study). Agreement was measured using unweighted kappa (k) for categorical data, the intraclass correlation coefficient (ICC) for continuous data, and percent agreement. The odds of disagreement with TM (comparing the TM-standard versus standard-standard studies) was assessed with logistic regression analysis. MAIN OUTCOME MEASURES: Three parameters were assessed: (1) category of strabismus, determined by observation without cover test; (2) angle of deviation at 0.33 and 6.0 m; and (3) ocular muscle action. RESULTS: Agreement on the category of strabismus was good (k > 0.61) other than for vertical deviations. However, there was good to excellent agreement between TM and standard examinations on the vertical (ICC = 0.78) and horizontal (ICC = 0.79) angles of deviation with 6-m fixation with the cover test. Muscle ratings agreed within one point for the lateral, superior, and inferior rectus muscle actions in more than 90% of the eyes examined. Although good agreement was observed in the TM-standard study, it was inferior to the agreement in the standard-standard study. Examination by TM increased the odds of disagreement compared with examination in person by twofold to threefold. CONCLUSIONS: Strabismus examination can be performed with a good level of reliability with the use of medium bandwidth video teleconferencing equipment. However, reduced reliability has been noted in the detection of small vertical deviations by inspection and in evaluating oblique muscle actions.

Adolescent↗
PubMed1994

The Americans with Disabilities Act. Emerging issues for ophthalmologists.

BACKGROUND: The Americans with Disabilities Act of 1990 is the most comprehensive federal law to address discrimination against an estimated 49 million Americans in the areas of employment, governmental services, public accommodations, transportation, and telecommunications. METHODS: The authors describe title I of the Americans with Disabilities Act and examine the challenges of implementing the employment provisions set forth in this legislation as they relate to visual impairment and disability. CONCLUSIONS: It is crucial that ophthalmologists understand the implications of the Americans with Disabilities Act when caring for individuals with visual impairments and communicating with their employers and other healthcare specialists. Ophthalmologists play an increasingly important role in shaping public policy toward people with visual impairments.

Activities of Daily Living↗
PubMed1996

Neuronal networks and self-organizing maps: new computer techniques in the acoustic evaluation of the infant cry.

Neuronal networks are computer-based techniques for the evaluation and control of complex information systems and processes. So far, they have been used in engineering, telecommunications, artificial speech and speech recognition. A new approach in neuronal network is the self-organizing map (Kohonen map). In the phase of 'learning', the map adapts to the patterns of the primary signals. If, the phase of 'using the map', the input signal hits the field of the primary signals, it resembles them and is called a 'winner'. In our study, we recorded the cries of newborns and young infants using digital audio tape (DAT) and a high quality microphone. The cries were elicited by tactile stimuli wearing headphones. In 27 cases, delayed auditory feedback was presented to the children using a headphone and an additional three-head tape-recorder. Spectrographic characteristics of the cries were classified by 20-step bark spectra and then applied to the neuronal networks. It was possible to recognize similarities of different cries of the same children as well as interindividual differences, which are also audible to experienced listeners. Differences were obvious in profound hearing loss. We know much about the cries of both healthy and sick infants, but a reliable investigation regimen, which can be used for clinical routine purposes, has yet not been developed. If, in the future, it becomes possible to classify spectrographic characteristics automatically, even if they are not audible, neuronal networks may be helpful in the early diagnosis of infant diseases.

Acoustics↗
PubMed2000

Telemedicine in radiotherapy treatment planning: requirements and applications.

BACKGROUND AND PURPOSE: Telemedicine facilitates decentralized radiotherapy services by allowing remote treatment planning and quality assurance of treatment delivery. A prerequisite is digital storage of relevant data and an efficient and reliable telecommunication system between satellite units and the main radiotherapy clinic. The requirements of a telemedicine system in radiotherapy is influenced by the level of support needed. In this paper we differentiate between three categories of telemedicine support in radiotherapy. RESULTS AND DISCUSSION: Level 1 features video conferencing and display of radiotherapy images and dose plans. Level 2 involves replication of selected data from the radiotherapy database - facilitating remote treatment planning and evaluation. Level 3 includes real-time, remote operations, e.g. target volume delineation and treatment planning performed by the team at the satellite unit under supervision and guidance from more experienced colleagues at the main clinic.

Humans↗
PubMed2004

A Paradox-based data collection and management system for multi-center randomized clinical trials.

We have developed a Paradox-based data collection and management system for large-scale multi-site randomized clinical trials. The system runs under Windows operating system and integrates Symantec pcAnywhere32 telecommunications software for data transmission and remote control sessions, PKZIP utility for the compression/decompression of transmitted data, and Stat/Transfer for exporting the centralized Paradox database for analyses. We initially developed this system for VA Cooperative Study #399 'The Effect of Antiarrhythmic Therapy in Maintaining Stability of Sinus Rhythm in Atrial Fibrillation', which collects over 1000 variables on 706 patients at 20 sites. Patient intake for this 5-year study began in March of 1998. We have also developed an enhanced version of this system, which is being used in the NIH-funded 'Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT)' that collects over 1200 variables on 1588 patients at 13 sites. Patient intake for this 4-year study began in October of 2000.

Data Collection↗