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PubMed1991

Toward an analysis of conscious activity: 2. The functions of sleep and wakefulness.

What we generally call information is created through interference between regular information and reverse information. In this process, conscious activity is the creator of information. We can assume that the following five-stage mechanism exists inside the brain: 1) a mechanism that creates consciousness and recognizes information; 2) a mechanism that accumulates information in the neural circuits; 3) a mechanism that combines and separates the self-conscious mind and fragments of accumulated information; 4) a mechanism that accesses the operating system or distributes information to localized neural circuits; and 5) a mechanism that allows the operating system to modify itself with an increase in the amount of information. These mechanisms can be considered to belong to the category of conscious activity, which is created by a combination of potentialization of sleep and potentialization of wakefulness.

Brain↗
PubMed2002

Using the Web to aid biochemists and microbiologists: an example of computer-based learning using PCR as an example.

The aim of this study was two-fold: to make available to the medical community a fast, efficient tool for troubleshooting PCR problems, and to demonstrate that hypermedia allow one to approach this kind of problem in a new, more useful way. The Web provides access to an enormous amount of information in the medical area, and in particular enables troubleshooting of new techniques in the medical laboratory. Currently it is possible to find textual information but it is not always easy to find hypermedia information. In many cases authors change only the means of dissemination of a book or paper to the Web, but do not adapt the information to the features of this new medium. The prototype of our hypermedia application was developed using Director and Flash programs (Macromedia), the application was developed from a decision tree built as a result of information compiled from expert PCR users and the existing literature. It was implemented on a website using Dreamweaver (Macromedia). The usefulness and possibilities of this application have been tested with physicians, medical laboratory technicians, and health science students, and have been proven to be more effective than traditional methods, both in education processes and in helping researchers and medical laboratory technicians in their daily work. The advance and popularization of the Internet in the medical profession requires information on the Web to adapt to the advantages offered by hypermedia. This new step must be taken, and the Web must offer medical users not only a different medium of information distribution but also a new way of handling and obtaining information.

Biochemistry↗
PubMed1999

Temporal binding, binocular rivalry, and consciousness.

Cognitive functions like perception, memory, language, or consciousness are based on highly parallel and distributed information processing by the brain. One of the major unresolved questions is how information can be integrated and how coherent representational states can be established in the distributed neuronal systems subserving these functions. It has been suggested that this so-called "binding problem" may be solved in the temporal domain. The hypothesis is that synchronization of neuronal discharges can serve for the integration of distributed neurons into cell assemblies and that this process may underlie the selection of perceptually and behaviorally relevant information. As we intend to show here, this temporal binding hypothesis has implications for the search of the neural correlate of consciousness. We review experimental results, mainly obtained in the visual system, which support the notion of temporal binding. In particular, we discuss recent experiments on the neural mechanisms of binocular rivalry which suggest that appropriate synchronization among cortical neurons may be one of the necessary conditions for the buildup of perceptual states and awareness of sensory stimuli.

Arousal↗
PubMed1997

Role of the temporal domain for response selection and perceptual binding.

Most cognitive functions are based on highly parallel and distributed information processing by the brain. A paradigmatic example is provided by the vertebrate visual system where numerous cortical areas have been described which analyse different types of visual information. At present, it is unclear how information can be integrated and how coherent representational states can be established in such distributed systems. We suggest that this so-called 'binding problem' may be solved in the temporal domain. The hypothesis is that synchronization of neuronal discharges can serve for the integration of distributed neurons into cell assemblies and that this process may underlie the selection of perceptually and behaviourally relevant information. We review experimental results, mainly obtained in the visual system, which support this temporal binding hypothesis.

Animals↗
PubMed2001

Visualization of bioavailable liposomal doxorubicin using a non-perturbing confocal imaging technique.

Commonly employed tissue processing techniques can significantly alter tissue drug distribution patterns for liposomal encapsulated drugs by virtue of drug leakage via loss of membrane integrity. We report here a method that has been developed to determine the fluorescence of bioavailable doxorubicin (DOX) in tissues after administration of liposomal DOX formulations. A non-perturbing confocal fluorescence microscopy (CFM) technique with image processing analysis was used with unprocessed fresh tissues. This method takes advantage of the fact that considerable quenching occurs when DOX is within liposomes, leading to the selective visualization of the fluorescence due to DOX released from liposomes. We demonstrate that fresh tissue confocal imaging can be applied to provide detailed drug distribution information with improved accuracy and is a superior method for analyzing tissue distribution of liposome entrapped fluorescent agents.

Animals↗
PubMed1997

Once again on cardiac transplantation. Flaws in the logic of the proponents.

In response to a paper written by Drs. Toshima and Kawai trying to refute my earlier article on the movement for cardiac transplantation in Japan, I present the results of my survey of the opinions of medical students and student nurses to prove that polls showing a majority of people supporting organ transplantation from so-called brain-dead persons, to which transplant protagonists rely heavily, merely reflect the failure of the mass media to distribute information on the negative aspects of organ transplantation to the public. Several major flaws in the logic of the proponents are pointed out to show how fragile their theoretical background is. Thus, the need for the distribution of better-balanced information to the public and continued debate on this most serious medical, ethical, social and cultural issue is emphasized.

Brain Death↗
PubMed2002

Characterisation of novel modified active carbons and marine algal biomass for the selective adsorption of lead.

This paper discusses the sorption performance of novel materials for the removal of lead(II) and copper(II) from near-neutral aqueous solutions. Active carbons with surface heteroatoms of oxygen and phosphorus have been prepared. The surface functional groups display weakly acidic ion exchange characteristics. The optimum solution pH for maximum metal sorption is related to the pK values of the surface functional groups. In oxygenated active carbons, pK values are not distinct but can be obtained by describing proton binding to the heterogeneous adsorbent surface as a continuous proton affinity distribution. Information derived from zeta-potential measurements combined with knowledge of the pK distribution function and concentration of surface functional groups has been used to explain the selectivity of oxidised active carbons towards lead(lI) in the presence of copper(II) from multi-metal bearing solutions. Marine algal-based biosorbents have been challenged with lead(II) and copper(II)-bearing wastewater. The weakly acidic carboxyl groups of structural polysaccharides present within the algal matrix display high sorption capacity for both metals. The negative surface charge of algal particles results in electrostatic interactions as well as coordination between metal species and the adsorbent surface. Proton affinity for the algal surface lowers the negative surface potential at pH values around 2. The surface functional groups in algae unlike those in oxidised active carbons may be represented by discrete acid-dissociation constant values. The influence of conformational differences in uronic-acid segments upon metal ion selectivity is discussed.

Adsorption↗
PubMed1995

Women's perceptions and experience of menopause: a focus group study.

Focus groups were used to investigate women's perception and experience of menopause, hormone replacement therapy, osteoporosis and doctor-patient relationships. Forty women aged between 45 and 55 years participated in seven focus groups. Most women thought that these topics were not widely or freely discussed in the community. Nevertheless they were able to share their experiences on this occasion. Lack of reliable, accessible and current information on menopause and related topics was identified as a problem. This was compounded by the contradictory nature of the information which was available. Hysterectomy and osteoporosis were identified as specific areas in which information was inadequate and not readily accessible. Solutions suggested by the women included distributing information pamphlets with contact numbers for further information to non-health-related settings such as hairdressing salons. The need to foster open discussion between women and their doctors was highlighted, with contributions required from both parties to develop a more equal partnership. A review of doctors' and women's surveillance practices with regard to hormone replacement therapy may also be warranted. We found focus groups a useful method for accessing women's experiences and perceptions. There was particular benefit in researchers being involved as moderators and scribes, and in an early post-focus group meeting to amplify and clarify records of the discussions. Small group size and an emphasis on confidentiality were, we believe, helpful strategies in encouraging discussion of intimate topics.

Attitude to Health↗
PubMed1993

Segmentation of medical images through competitive learning.

In image analysis applications, segmentation of gray-level images into meaningful regions is an important low-level processing step. Various approaches to segmentation investigated in the literature, in general, use either local information of gray-level values of pixels (region growing based methods, for example) or the global information (histogram thresholding based methods, for example). Application of these approaches for segmenting medical images often does not provide satisfactory results. Medical images are usually characterized by low local contrast and noisy or faded features causing unacceptable performance of local information based segmentation methods. In addition, because of a large amount of structural information found in medical images, global information based segmentation methods yield inadequate results in region extraction. We present a novel approach to image segmentation that combines local contrast as well as global gray-level distribution information. The presented method adaptively learns useful features and regions through the use of a normalized contrast function as a measure of local information and a competitive learning based method to update region segmentation incorporating global information about the gray-level distribution of the image. In this paper, we present the framework of such a self organizing feature map, and show the results on simulated as well as real medical images.

Algorithms↗
PubMed2002

"Remember where you last saw that card": children's production of external symbols as a memory aid.

Four experiments examined the age at which children start to use external symbols to aid their memory and how external symbol use affects both their memory performance and information allocation strategies. In Experiment 1, children in Grades 1, 3, 5, and 7 played a memory card game (Concentration) twice, once with the opportunity to make notes to aid performance and once without the opportunity. Grades I and 3 students tended to produce nonmnemonic notations, whereas Grades 5 and 7 students were more likely to produce functional, adultlike notations that aided performance in the task. In Experiments 2a and 2b, unexpected removal of children's notations led to a decrease in performance. suggesting that the spontaneously produced notations were being used as an external store rather than as an aid to encoding information. Experiment 3 examined whether all information was placed in external storage or if some types of information remained in memory. Grade 7 students who had their notations unexpectedly taken away were able to recognize the identity of the cards they had previously seen but had more difficulty remembering their locations. They appeared to place the location information mainly in external storage while retaining the identity information in memory. These results suggest that in mid-childhood, children begin to distribute information actively between internal and external memory storage.

Audiovisual Aids↗
PubMed2004

New approaches for exploring anatomical and functional connectivity in the human brain.

Information processing in the primate brain is based on the complementary principles of modular and distributed information processing. The former emphasizes the specialization of functions within different brain areas. The latter emphasizes the massively parallel nature of brain networks and the fact that function also emerges from the flow of information between brain areas. The localization of function to specific brain areas ("functional segregation") is the commonest approach to investigating function; however, an emerging, complementary approach ("functional integration") describes function in terms of the information flow across networks of areas. Here, we highlight recent advances in neuroimaging methodology that have made it possible to investigate the anatomical architecture of networks in the living human brain with diffusion tensor imaging (DTI). We also highlight recent thinking on the ways in which functional imaging can be used to characterize information transmission across networks in the human brain (functional and effective connectivity).

Animals↗
PubMedDate not supplied

Carbon monoxide poisoning during ice storms: a tale of two cities.

This is a retrospective case series conducted at two university hospital emergency departments of 68 patients with a discharge diagnosis of carbon monoxide (CO) poisoning presenting during two different ice storms (March 1991 and February 1994) in two cities (Rochester, NY, and Nashville, TN). Fifty-five patients were seen over 10 d in Rochester and 13 patients over 4 d in Nashville. The main sources of CO exposure were the indoor use of gasoline generators (40 patients), propane or kerosene heaters (9 patients), and charcoal grills (8 patients). Six patients did not speak English fluently (5 Asian patients in Nashville and 1 Greek patient in Rochester). The use of charcoal grills was the most common CO source in Nashville, occurring exclusively in patients of Asian descent, 5 of whom did not speak English. In Rochester, the use of gas generators was the most common CO source. Ice storms represent a significant threat to populations affected by prolonged power outages. Different cities will be affected in different ways. When ice storms occur, the media should distribute information about potential sources of CO exposure. In some cases, the message may need to be distributed by alternative methods to populations who do not speak English or do not have access to mainstream media.

Adolescent↗
PubMed2005

[An examination in comparison Web site with other root on the revised information of drug package insert].

To obtain revised information on drug package inserts, we evaluated the quality and comprehensibility of such information provided by the Web site of the Pharmaceuticals and Medical Devices Agency (PMDA site), medical representatives (MRS), Drug Safety Updates (DSUS), and informational publications of the wholesale distributor Company F (wholesaler F). In the comparison of the total amount of revised information obtained from April 2003 to March 2004, the PMDA site was 90% or greater of comprehensible. In comparison with the distribution information on the notice of the Ministry of Health, Labor and Welfare, an informational delay or lack occasionally occurred and variations among pharmaceutical companies were observed. Moreover, on the PMDA site, the number of revisions was 1972. Among them, clinically important information, such as warnings, contraindications, adverse effects, and drug interactions, totaled 37%. From these results, it is suggested that there are variations in the information from each pharmaceutical company on the PMDA site although the site is excellent in terms of comprehensibility.

Adverse Drug Reaction Reporting Systems↗
PubMed2006

Group decision making in hidden profile situations: dissent as a facilitator for decision quality.

The effect of diversity in individual prediscussion preferences on group decision quality was examined in an experiment in which 135 three-person groups worked on a personnel selection case with 4 alternatives. The information distribution among group members constituted a hidden profile (i.e., the correct solution was not identifiable on the basis of the members' individual information and could be detected only by pooling and integrating the members' unique information). Whereas groups with homogeneous suboptimal prediscussion preferences (no dissent) hardly ever solved the hidden profile, solution rates were significantly higher in groups with prediscussion dissent, even if none of these individual prediscussion preferences were correct. If dissent came from a proponent of the correct solution, solution rates were even higher than in dissent groups without such a proponent. The magnitude of dissent (i.e., minority dissent or full diversity of individual preferences) did not affect decision quality. The beneficial effect of dissent on group decision quality was mediated primarily by greater discussion intensity and to some extent also by less discussion bias in dissent groups.

Adult↗
PubMed2002

Atmospheric aerosol measurements of 238U and 232Th at Fernald, Ohio, and implications on inhalation dose calculations.

Measurements of the aerosol size distribution of 238U and 232Th at the U.S. Department of Energy's Fernald Environmental Management Project site were made to improve the inhalation dose calculations to off-site individuals. For approximately 1 y an 8-stage cascade impactor was co-located with a high volume sampler and operated at the Fernald Environmental Management Project site to collect aerosol samples. During most of the year, the site was dominated by giant particles with more than 70% of the mass of 238U above 15 microm. The seasonal average of the activity median aerodynamic diameter, based on the impactor samples, which excluded particles >15 microm, for both uranium and thorium was approximately 6.5 microm. These numbers reflect the activities at the site and the domination of the resuspension processes. During most sampling periods the size distribution was bimodal. Thorium concentrations were comparable to the uranium concentrations during the late spring and summer period and decreased to approximately 25% of the 238U concentration in the late summer. Fernald Environmental Management Project is required to calculate the maximum allowable dose from airborne emissions, excluding radon, to meet NESHAP compliance. These calculations assume an AMAD of 1 microm. We found that if you combine size distribution information with the latest ICRP 66 lung model you reduce the estimated dose by a factor of 7. Inclusion of the size distribution of radionuclides at any sampling site would substantially improve the dose estimates to the population.

Aerosols↗
PubMed2001

Beyond requirements: residency management through the Internet.

HYPOTHESIS: An Internet application could collect information to satisfy documentation required by the Residency Review Committee. Beyond replacing a difficult and inefficient paper system, it would collect, process, and distribute information to administration, faculty, and residents. DESIGN: Descriptive study. SETTING: An integrated residency of 18 services at a university teaching hospital with 4 affiliated institutions. PARTICIPANTS: Residency administrators, faculty, and residents. INTERVENTIONS: The application included a procedure recorder, resident evaluation of faculty and rotations, goals and objectives (stratified by service and resident level), and matching faculty evaluation of residents with these goals as competencies. Policies, schedules, research opportunities, clinical site information, and curriculum support were created. MAIN OUTCOME MEASURES: Degree of compliance with Residency Review Committee standards, number of deficiencies corrected, and quantity and quality of information available to administration, faculty, and residents. RESULTS: The Internet system increased resident compliance for faculty and rotation evaluations from 20% and 34%, respectively, to 100%, which was maintained for 22 months. These evaluations can be displayed individually, in summary grids, and as postgraduate year-specific averages. Faculty evaluations of residents can be reviewed throughout the system. The defined category report for procedures, which had deficiencies in the preceding 6 years, had none for the last 2 years. The Internet application provides Accreditation Council for Graduate Medical Education-validated operative logs to regulatory agencies. CONCLUSIONS: A Web-based system can satisfy requirements and provide processed data that are of better quality and more complete than our paper system. We are now able to use scarce time and personnel to nurture developing surgical residents instead of shuffling paper.

Connecticut↗
PubMed2003

An improved stereologic method for three-dimensional estimation of particle size distribution from observations in two dimensions and its application.

Single enzyme-altered hepatocytes; altered hepatic foci (AHF); and nodular lesions have been implicated, respectively in the processes of initiation, promotion, and progression in rodent hepatocarcinogenesis. Qualitative and quantitative analyses of such lesions have been utilized both to identify and to determine the potency of initiating, promoting, and progressor agents in rodent liver. Of a number of possible parameters determined in the study of such lesions, estimation of the number of foci or nodules in the liver is very important. The method of Saltykov has been used for estimating the number of AHF in rat liver. However, in practice, the Saltykov calculation has at least two weak points: (a) the size class range is limited to 12, which in many instances is too narrow to cover the range of AHF data obtained; and (b) under some conditions, the Saltykov equation generates negative values in several size classes, an obvious impossibility in the real world. In order to overcome these limitations in the Saltykov calculations, a study of the particle size distribution in a wide-range, polydispersed sphere system was performed. A stereologic method, termed the 25F Association method, was developed from this study. This method offers 25 association factors that are derived from the frequency of different-sized transections obtained from transecting a spherical particle, thus expanding the size class range to be analyzed up to 25, which is sufficiently wide to encompass all rat AHF found in most cases. This method exhibits greater flexibility, which allows adjustments to be made within the calculation process when NA((k,k)), the net number of transections from the same size spheres, was found to be a negative value, which is not possible in real situations. The reliability of the 25F Association method was tested thoroughly by computer simulation in both monodispersed and polydispersed sphere systems. The test results were compared with the original Saltykov method. We found that the 25F Association method yielded a better estimate of the total number of spheres in the three-dimensional tissue sample as well as the detailed size distribution information. Although the 25F Association method was derived from the study of a polydispersed sphere system, it can be used for continuous size distribution sphere systems. Application of this method to the estimation of parameters of preneoplastic foci in rodent liver is presented as an example of its utility. An application software program, 3D_estimation.exe, which uses the 25F Association method to estimate the number of AHF in rodent liver, has been developed and is now available at the website of this laboratory.

Animals↗
PubMed2006

Guidelines for interactions between clinical faculty and the pharmaceutical industry: one medical school's approach.

A productive and ethical relationship between the pharmaceutical industry and physicians is critical to improving drug discovery and public health. In response to concerns about inappropriate financial relationships between the pharmaceutical industry and physicians, national organizations representing physicians or industry have made recommendations designed to reduce conflicts of interest, legal exposure, and dissemination of biased information. Despite these initiatives, the prescribing practices of physicians may be unduly influenced by the marketing efforts of industry and physicians may inadvertently distribute information that is biased in favor of a commercial entity. Moreover, physicians may be vulnerable to prosecution through federal anti-kickback and false claims statutes because of potentially inappropriate financial relationships with pharmaceutical companies. Since academic medical centers have a critical role in establishing professional standards, the faculty of Yale University School of Medicine developed guidelines for the relationships of faculty with the pharmaceutical industry, which were approved in May 2005. Input from clinical faculty and from representatives of the pharmaceutical industry was utilized in formulating the guidelines. In contrast to existing recommendations, the Yale guidelines, which are presented as an Appendix here, ban faculty from receiving any form of gift, meal, or free drug sample (for personal use) from industry, and set more stringent standards for the disclosure and resolution of financial conflict of interest in Yale's educational programs. The growing opportunities for drug discovery, the need to use medications in a more evidence-based manner, and preservation of the public trust require the highest professional standards of rigor and integrity. These guidelines are offered as part of the strategy to meet this compelling challenge.

Codes of Ethics↗