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At least 1,063 records · Page 59Linked to original sources

PubMed1999

Does over-accomodation occur when using aircraft head-up displays?

BACKGROUND: Whether over-accommodation is caused by the use of head-up displays is still under debate. Most prior experimentation has involved cognitively demanding tasks, which are known to affect the accommodation response. The simulations have often been unrealistic and involved short working distances. HYPOTHESIS: Over-accommodation is caused not by the presence of a head-up display per se, but rather by the cognitive demand of the task. METHODS: The effect of increasing the task cognitive load and the use of forward looking infra-red imagery (FLIR) on the ocular accommodative response and task performance was assessed with a realistic head-up display assisted flying task. FLIR increases cognitive load due to its poor resolution and the need for interpretation of the images. RESULTS: Over-accommodation was found to be small in magnitude (0.17+/-0.03D; range -0.02-0.45D) occurring only with cognitively demanding tasks and with forward looking infrared imagery. Response times to detect tanks in the outside world scene were slower with increased cognitive load and forward looking infra-red imagery, along with a reduced detection rate, decreased accuracy of tracking tanks in the outside world and poorer control of the head-up display pitch ladder. When discrimination was added to detection in an outside world task, decisions were delayed until they could be accurately made, rather than performance degraded. CONCLUSION: The use of a virtual head-up display in a simulated aircraft environment did not adversely affect ocular accommodation. However, increased cognitive demand or FLIR imagery caused significant inward shifts of accommodation.

Accommodation, Ocular↗

PubMed2006

Virtual house calls: legal challenges to remote caregiving.

Medicine in the digital age requires new thinking to bring cost-effective and quality medical care to patients in home settings. Along with the promise of remote treatment advances come many challenges relating to technology, regulation, and the building of new virtual teams and social structures to support the remote environment. For remote caregiving to succeed, the legal and ethical issues of home monitoring and ubiquitous computing must be addressed side-by-side with the technology advances.

House Calls↗

PubMedDate not supplied

[The recycling of waste water and mosquitoes].

Recycling waste water in the Achères complex (North-West Paris) is based on both sophisticated industrial techniques and simple agricultural methods. The sewage farms and settling pools provide suitable breeding sites for more than ten mosquito species. Aedes caspius is the major pest for the local population. Moreover Culex pipiens (anthropophilic form) breeds in the sewers of the neighbouring towns. Mosquito control is based early ground treatment of breeding sites. Temephos and fenotrothion are used against A. caspius. Spherimos (Bacillus sphaericus) is used to control C. pipiens. The two insecticides have no adverse effect on humans or the environment and Spherimos is harmless. Aedes pest have been virtually eliminated. Urban Culex control is generally good despite being performed by less well trained municipal employees. In the areas treated by the specialized team of the SIAAP, pest mosquitoes have disappeared. The techniques used in the Achères complex do not require sophisticated equipment. Thus, if adapted to local ecological, epidemiological and financial conditions they could be transferred to developing countries.

Aedes↗

PubMed1993

Specific placement of tryptophan in the catalytic sites of Escherichia coli F1-ATPase provides a direct probe of nucleotide binding: maximal ATP hydrolysis occurs with three sites occupied.

Residue beta Y331 of Escherichia coli F1-ATPase is known from previous affinity labeling, mutagenesis, and lin-benzo-ADP binding experiments to interact directly with the adenine moiety of substrates bound in catalytic sites. Here we mutagenized beta Y331 to tryptophan. Mutant cells grew well on succinate or limiting glucose; purified mutant F1 had kappa cat/Km and lin-benzo-ADP binding characteristics similar to wild type. Fluorescence from beta W331 residues exhibited a maximum at 349 nm, indicating a polar environment in unoccupied sites. ATP, ADP, or AMPPNP caused virtually complete quenching of beta W331 fluorescence, so that the fluorescence of mutant F1 with occupied catalytic sites resembled that of wild-type enzyme. Therefore the beta W331 fluorescence provided a direct probe of nucleotide binding to catalytic sites under true equilibrium conditions. We measured ATP binding and hydrolysis in parallel experiments and found that occupancy of one or two catalytic sites per F1 molecule did not yield significant rates of hydrolysis while occupancy of all three sites yielded Vmax rates. Km(ATP) was similar to Kd3, the Kd for ATP binding to the third catalytic site. We also measured AMPPNP and ADP binding parameters. For ADP, the "on" rate at the first catalytic site was much faster (> or = 5 x 10(5) M-1 s-1) than seen previously by centrifuge column procedures, although the Kd was not much changed. For AMPPNP, the "on" rate at the first site was 2 orders of magnitude less than for ADP or ATP, and the Kd was similar to that for ADP.

Adenosine Diphosphate↗

PubMed2003

An implementation of a virtual patient record using Web services.

Virtual patient records provide a means for integrated access to patient information that may be scattered around different healthcare settings. Within the boundaries of a health district providing all levels of care, this concept can be implemented in a corporate Intranet environment to support longitudinal patient care activities across the participating healthcare providers. In this context, a virtual patient record implementation enables autonomous healthcare providers to operate in a cooperative working environment and apply continuity of care. Workflow and web services technologies provide an appropriate infrastructure for satisfying collaboration and coordination requirements by integrating heterogeneous healthcare applications and by automatically routing the medical information needed to authorized actors in a healthcare process. This paper presents a virtual patient record architecture that allows integrating geographically dispersed medical information within a health district and enhancing collaboration and coordination of authorized workgroups using workflow and web services technologies. An implementation of the proposed architecture is also presented.

Efficiency, Organizational↗

PubMed1983

Behavior, the environment, and the health of the individual.

The contribution of medical treatment to the health of the world's population was virtually nil until the 20th century and continues to be small. In contrast, the contribution of the prevention of disease through modification of the environment (improved ventilation, drainage, sewage disposal) has been great. This effect is seen in the dramatic rise in the population of Europe since the early 18th century. The major causes of death and disability in developed countries, however, have changed markedly during the present century. Most of the risk factors associated with these diseases are behavioral in nature (cigarette smoking, excessive caloric intake, excessive alcohol consumption, inadequate exercise, etc.). Accordingly, modifying the environment is no longer enough--one must modify the behavior of the individual. To do this, one needs an effective technology for modifying behaviors that have important health consequences. Such a behavioral technology is being developed. Some of the principles underlying this technology will be illustrated by their application to one modern scourge--cigarette smoking.

Behavior↗

PubMedDate not supplied

Real-time 3D human capture system for mixed-reality art and entertainment.

A real-time system for capturing humans in 3D and placing them into a mixed reality environment is presented in this paper. The subject is captured by nine cameras surrounding her. Looking through a head-mounted-display with a camera in front pointing at a marker, the user can see the 3D image of this subject overlaid onto a mixed reality scene. The 3D images of the subject viewed from this viewpoint are constructed using a robust and fast shape-from-silhouette algorithm. The paper also presents several techniques to produce good quality and speed up the whole system. The frame rate of our system is around 25 fps using only standard Intel processor-based personal computers. Besides a remote live 3D conferencing and collaborating system, we also describe an application of the system in art and entertainment, named Magic Land, which is a mixed reality environment where captured avatars of human and 3D computer generated virtual animations can form an interactive story and play with each other. This system demonstrates many technologies in human computer interaction: mixed reality, tangible interaction, and 3D communication. The result of the user study not only emphasizes the benefits, but also addresses some issues of these technologies.

Art↗

PubMed2006

Snake's perspective on heat: reconstruction of input using an imperfect detection system.

Two groups of snakes possess an infrared detection system that is used to create a heat image of their environment. In this Letter we present an explicit reconstruction model, the "virtual lens," which explains how a snake can overcome the optical limitations of a wide aperture pinhole camera, and how ensuing properties of the receptive fields on the infrared-sensitive membrane may explain the behavioral performance of this sensory system. Our model explores the optical quality of the infrared system by detailing how a functional representation of the thermal properties of the environment can be created. The model is easy to implement neuronally and agrees well with available neuronal, physiological, and behavioral data on the snake infrared system.

Animals↗

PubMed2006

Comparison of results of virtual-reality simulator and training model for basic ureteroscopy training.

BACKGROUND AND PURPOSE: The traditional method of acquiring surgical skills is by apprenticeship and involves an extensive period of training with patients. Model-based and virtual reality simulation is gaining interest as alternative training, allowing repetitive practice in a low-risk environment. The objective of this study was to determine if a materials, model-based training format and an interactive virtual-reality simulator could provide equivalent teaching of basic ureteroscopy skills to the inexperienced medical student. SUBJECTS AND METHODS: Sixteen first-year medical students received the same didactic session and video viewing on cystoscopy, guidewire access to the upper urinary tract, and ureteroscopy with intracorporeal laser lithotripsy and stone extraction by the same instructor. The participants were then randomized into two study groups: Group 1 was trained on the ureteroscopy training model (TMU) from Limbs & Things and Group 2 on the Simbionix UROMentor virtual-reality simulator (VRS) until the participants could perform the procedure independently. Two months later, the participants independently performed a ureteroscopic procedure on a pig kidney/ureter model and were graded from 1 to 5 on their ability to complete the steps of the procedure and the quality of their performance (handling of tissue, efficiency, instrument handling, knowledge of instruments, flow of operation, use of assistants, and knowledge of the specific procedure) for a possible total of 35 points. RESULTS: All participants were able to perform the steps of the procedure correctly. The TMU group and the VRS group received a mean of 22.9 +/- 4.8 and 23.6 +/- 5.4 points, respectively (P = 0.38) for their qualitative assessment. CONCLUSION: The medical students' skills and ability to perform a basic ureteroscopic stone-management procedure was independent of the training modality (VRS or TMU). Incorporating either of these devices into the preliminary training of urology residents may improve their initial clinical performance of these skills.

Adult↗

PubMed2003

Virtual reality training for health-care professionals.

Emerging changes in health-care delivery are having a significant impact on the structure of health-care professionals' education. Today it is recognized that medical knowledge doubles every 6-8 years, with new medical procedures emerging everyday. While the half-life of medical information is so short, the average physician practices 30 years and the average nurse 40 years. Continuing education thus represents an important challenge to face. Recent advances in educational technology are offering an increasing number of innovative learning tools. Among these, Virtual Reality represents a promising area with high potential of enhancing the training of health-care professionals. Virtual Reality Training can provide a rich, interactive, engaging educational context, thus supporting experiential learning-by-doing; it can, in fact, contribute to raise interest and motivation in trainees and to effectively support skills acquisition and transfer, since the learning process can be settled within an experiential framework. Current virtual training applications for health-care differ a lot as to both their technological/multimedia sophistication and to the types of skills trained, varying for example from telesurgical applications to interactive simulations of human body and brain, to virtual worlds for emergency training. Other interesting applications include the development of immersive 3D environments for training psychiatrists and psychologists in the treatment of mental disorders. This paper has the main aim of discussing the rationale and main benefits for the use of virtual reality in health-care education and training. Significant research and projects carried out in this field will also be presented, followed by discussion on key issues concerning current limitations and future development directions.

Computer Simulation↗

PubMedDate not supplied

Management of allergies to animals.

Allergy to animals affects between 15 to 30% of atopic persons and about the same proportion of all those who work with laboratory animals. The responsible allergens are contained in the urine, saliva, and secretions of furred animals. The allergens apparently dry on fur, bedding, or other fomites so that with disturbance, the antigen becomes airborne on particles or "vectors" of diverse size. Many of these vectors are small enough to remain airborne and reach the lower airway. They adhere to surfaces in the environment such as rugs, walls, and clothing, so that animal allergens are found in virtually every sample of household dust and in the air and surfaces throughout most research facilities. This creates a reservoir of allergen that makes total elimination of the allergen from any environment very difficult. It then becomes important to understand the minimum level of allergen capable of inducing symptoms in sensitized patients so strategies can be developed to reduce exposures to below these limits. Otherwise, management will depend on nearly complete avoidance of animal dander, a difficult task. Alternatively, it will be necessary to modify the allergic host with drugs or immunotherapy.

Air Pollutants↗

PubMed2001

Towards virtual reality stimulation in force platform posturography.

We developed a stimulation technique on the basis of virtual reality methods for balance investigation performed in balance laboratories of otorhinolaryngological clinics and institutes of occupational health. Such a stimulation technique is greatly progressive in the sense that by creating virtual moving views and "virtual worlds" inside which the subject is located it is possible to make effective stimuli that would be very difficult or even impossible to set in any real environment. We tested our system on healthy subjects and found out that this kind of virtual reality stimulation system is very useful for balance analysis.

Adult↗

PubMedDate not supplied

Lessons learned from teaching web-based courses: the 7-year itch.

TOPIC: Lessons learned from teaching web-based courses: the 7-year itch. SOURCES OF INFORMATION: Increased sophisticated technological communications are rapidly changing the teaching and learning environment. Nursing educators must respond by developing new ways of teaching. Because of these changes, new ways of teaching, course delivery methods, and classroom environments are being discovered. The Internet and the cyberspace environment allow students from all over the nation to sit in the same virtual classroom and "attend lecture" with one instructor. This article describes lessons learned from seven years of teaching on the web on both undergraduate and graduate levels. CONCLUSION: The major challenges for faculty relate to the creation of a stimulated learning environment for communication and interaction among the students, course preparation, workload, time management. Additional challenges are the methods of classroom discussions, teaching methods, responding to students, and teaching a 2-unit clinical component on-line. For students, issues of learning styles, motivation, and class participation are discussed. Results of the students' responses to a 10-item Likert-type course evaluation tool as well as issues for future web educators are presented.

Education, Nursing↗

PubMed1998

Virtual anthropology (VA): methodological aspects of linear and volume measurements--first results.

Virtual Anthropology (VA) is the three-dimensional analysis of anthropological objects within a computer environment. For the investigation of fossil hominid material the VA approach is a very powerful and essential technique to obtain quantitative and qualitative data. The permanent accessibility of the virtual objects and the possibility to study inner structures are striking advantages. The present study is an attempt to evaluate the usefulness and problems of VA and to provide data on accuracy and reproducibility. 10 Homo sapiens skulls were CT-scanned and were measured on the computer and with established methods (calipers and mustard seeds/water displacement). Different co-variables like sex, age, observer, and class and dimension of measurement were included. The results are very promising: The mean of absolute difference for linear measurements is 0.71 mm +/- 0.55 (0.58% +/- 0.49), and 31.59 ccm +/- 13.37 (2.26% +/- 0.86) for volume measurements. Reproducibility is 0.11 mm +/- 0.15 for located landmarks and 0.37 mm +/- 0.41 for relocating landmarks. Age and class of measurement are significant factors.

Anthropology, Physical↗

PubMed2006

Motion sickness susceptibility.

Motion sickness can be caused by a variety of motion environments (e.g., cars, boats, planes, tilting trains, funfair rides, space, virtual reality) and given a sufficiently provocative motion stimulus almost anyone with a functioning vestibular system can be made motion sick. Current hypotheses of the 'Why?' of motion sickness are still under investigation, the two most important being 'toxin detector' and the 'vestibular-cardiovascular reflex'. By contrast, the 'How?' of motion sickness is better understood in terms of mechanisms (e.g., 'sensory conflict' or similar) and stimulus properties (e.g., acceleration, frequency, duration, visual-vestibular time-lag). Factors governing motion sickness susceptibility may be divided broadly into two groups: (i) those related to the stimulus (motion type and provocative property of stimulus); and (ii) those related to the individual person (habituation or sensitisation, individual differences, protective behaviours, administration of anti-motion sickness drugs). The aim of this paper is to review some of the more important factors governing motion sickness susceptibility, with an emphasis on the personal rather than physical stimulus factors.

Animals↗

PubMed2006

Laser imaging and computer-aided design and computer-aided manufacture in prosthetics and orthotics.

Although Hanger Orthopedic Group, Inc., has been developing clinical protocols for its INSIGNIA scanner for more than 2 years, there are many applications that are currently in development and will be released over the next 2-year period after this publication. It is the goal of Hanger Orthopedic Group, Inc., to replace all plaster casting procedures with the laser scan and move toward a paperless environment where all images and documents are passed through its virtual network. INSIGNIA currently has five major production centers throughout the United States, which support more than 600 INSIGNIA certified clinicians. These clinicians staff more than 600 clinics in North America, all under the Hanger company name. The central fabrication service and the central design center processes hundreds of shapes per day (Fig. 27). So that any clinician in the field can use the expertise of the central designers and central fabricators to help with overflow or problems they might be having, the network that exists within Hanger is tied together and enhanced by INSIGNIA. Through virtual modification and centralization of these services, each patient receives the virtual collaboration of several clinicians with a total of years of experience. INSIGNIA has enhanced the patient experience. The enhancement is not only in removing the plaster from the process, but also in exposing each patient to the team of prosthetic experts working collaboratively behind the scenes. The rehabilitation industry continues to be bombarded with compliance paperwork and justifications. The INSIGNIA scan and resulting measurement reports give inherent strength to justifications based on volume change, surgical revisions, or tissue change. The files are kept in a data warehouse where they are vaulted and preserved presumably forever. Also, any of the shape graphics or measurement instruments can be printed into a discrete report that can become part of the patient's permanent record. Many physicians receive update letters from their orthotic and prosthetic clinician with a status update before and after treatment of their patient. This update includes a descriptive narrative, a printout of the pertinent metrics, a printout of the scan graphic, and often a digital image of the patient wearing the device (Fig. 28). The network is HIPAA compliant, and all private health information is held in tight security. If a practitioner does not have a HIPAA agreement in place with Hanger Orthopedic Group, Inc., and would like one, or ifa practitioner would like to have an INSIGNIA representative call or visit with more information, the practitioner is encouraged to call 1-800-4-HANGER and request an INSIGNIA in-service or visit INSIGNIA on the web at www.hanger.com.

Adult↗

PubMed2001

Inhibiting effects of chloroform on anaerobic microbial consortia as monitored by the Rantox biosensor.

The Rantox biosensor was designed for anaerobic wastewater treatment process control, and detects modifications of the feed based on the response of the acetoclastic methanogens contained in the sensor to periodic pulses of a concentrated organic substrate. The biosensor was tested under various operating conditions at the laboratory scale, in parallel with a digester under control fed on the same substrate. The aim was to evaluate the response of the biosensor in the presence of an incoming organic toxic compound (CHCl3). The experimental set-up, i.e. the biosensor and the digester, was connected to an automated control system developed under LabVIEW environment for data acquisition and operational sequence programming (the Rantox Virtual Instrument). Biomasses with different activities were used as inocula, and inhibition was induced by dosing chloroform according to two different procedures. The results showed good sensitivity and rapid response of the biosensor to feed intoxication. The presence of chloroform was detected by the Rantox with a rapid and visible response, and well in advance with respect to the digester.

Anaerobiosis↗

PubMed2001

The present and future of telemedicine in Japan.

Telemedicine has always developed in close relation with communication technology. When only aural telephones were used, several experiments of telemedicine were carried out by utilizing telephone lines. When INS64 (ISDN with 64 kbits) and telecommunication satellites came onto the scene, experiments for telemedicine began to be conducted accordingly using the cutting-edge technology of the time. In this paper, one of the three categories of telemedicine, mainly tele-consultation that includes tele-pathology and tele-radiology, will be discussed with some examples conducted in Japan. As time goes on, the aim of telemedicine has also been changing. In 1996, the Japanese government gave the go ahead for telemedicine along its deregulation policies. Telemedicine including tele-home care in the 21st century will use the Internet and digital HDTV (high-definition TV) technology for information and data management interchangeably both at domestic and global levels in the medical environment. Also, our dream of a hyper-hospital or virtual hospital will be realized in cyberspace before long, but first we may have to overcome several tough problems such as the protection of privacy data, malpractice and vulnerability of technology relevant to the Internet and telecommunications satellite system as a whole.

Computer Communication Networks↗