Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PROJECTIVE TECHNICS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,549 records · Page 86Linked to original sources

Methods for national population forecasts: a review.

"Three widely used classes of methods for forecasting national populations are reviewed: demographic accounting/cohort-component methods for long-range projections, statistical time series methods for short-range forecasts, and structural modeling methods for the simulation and forecasting of the effects of policy changes. In each case, the major characteristics, strengths, and weaknesses of the methods are described. Factors that place intrinsic limits on the accuracy of population forecasts are articulated. Promising lines of additional research by statisticians and demographers are identified for each class of methods and for population forecasting generally."

Cohort Studies↗

Dynamic in vitro quantification of bioprosthetic heart valve leaflet motion using structured light projection.

Quantification of heart valve leaflet deformation during the cardiac cycle is essential in understanding normal and pathological valvular function, as well as in the design of replacement heart valves. Due to the technical complexities involved, little work to date has been performed on dynamic valve leaflet motion. We have developed a novel experimental method utilizing a noncontacting structured laser-light projection technique to investigate dynamic leaflet motion. Using a simulated circulatory loop, a matrix of 150-200 laser light points were projected over the entire leaflet surface. To obtain unobstructed views of the leaflet surface, a stereo system of high-resolution boroscopes was used to track the light points at discrete temporal points during the cardiac cycle. The leaflet surface at each temporal point was reconstructed in three dimensions, and fit using our biquintic hermite finite element approach (Smith et al., Ann. Biomed. Eng. 26:598-611, 2001). To demonstrate our approach, we utilized a bovine pericardial bioprosthetic heart valve, which revealed regions of complex flexural deformation and substantially different shapes during the opening and closing phases. In conclusion, the current method has high spatial and temporal resolution and can reconstruct the entire surface of the cusp simultaneously. Because it is completely noncontacting, this approach is applicable to studies of fatigue and bioreactor technology for tissue engineered heart valves.

Algorithms↗

Aging and social expenditures in Italy: some issues associated with population projections.

"After describing the main results of the recent Italian population projections, and some possible consequences...aging may have on social expenditures, this paper focuses on attempts to improve the accuracy of development assumptions, with special regard to natural components. Emphasis is placed on the importance of applying specific methodological tools to define self-explanatory assumptions for fertility and mortality and to produce projections which could be considered, with reasonable limitations, as real forecasts."

Demography↗

Sensitivity analysis in a multidimensional demographic projection model with a two-sex algorithm.

"Formulas are derived for the effect that a slight change in the occurrence/exposure rate of the multidimensional projection model has on the elements of the population vector. The projection model classifies the population by sex, age, and marital status. The model includes a two-sex algorithm in order to ensure consistency between numbers of male and female marriages, number of divorces for the two sexes, and new widows (widowers) and deceased spouses. The sensitivity functions and elasticities are applied to data from the Netherlands for the period 1980-1984. The results indicate that marriage market mechanisms, in particular competition and substitution effects, are reasonably well modelled."

Age Distribution↗

Projecting interregional migration balances within a multiregional cohort-component framework.

"The main themes of the paper are developed in three parts. First, the setting for the study is established by reviewing the foundational theory of multiregional population projections, and by detailing how interregional migration is projected within this approach. Second, we will identify the requirements for making multiregional population projections in Canada and undertake to explain why the conventional approach to projecting interregional migration produces less than satisfactory results. Third, an alternative method for projecting interregional migration is proposed."

Americas↗

Measuring the accuracy of population forecasts.

The accuracy of population projections is discussed, with specific reference to population forecasts for development planning purposes. The author notes that errors in making population forecasts depend on the parameter values used in the calculations, and that such errors can be avoided if the demographic models used are seen not as stochastic but as models with random parameters. "For such models the present article derives estimations of the covariance matrices of forecasts of the social and age composition of the population."

Age Distribution↗

Urban change in the third world: are recent trends a useful pointer to the urban future?

"This paper has three aims. The first is to examine the reliability of the data base for the statistics which are used as the basis for commenting on urban change in 'the Third World'. The second is to explore whether valid generalisations about urban change can be made for the Third World. And the third is to examine the validity of United Nations projections for the Third World's urban future."

Data Collection↗

[A demographic forecasting model with reference to population groups that intermarry, using the example of the Evangelical Church in Austria].

"This research note develops a multi-state population projection model in which inter-marriage between the states and the following uncertainty about the state of the children plays a major role. Since only 5% of the Austrian population belong to the Evangelical Church, but more than 80% of their members marry partners not belonging to the church, the question of the percentage of children from mixed marriages that become church members turns out to be vital for the future size and age composition of the church." Five different scenarios to the year 2030 are examined. (SUMMARY IN ENG)

Acculturation↗

Global gene mining and the pharmaceutical industry.

Worldwide efforts are ongoing in optimizing medical treatment by searching for the right medicine at the right dose for the individual. Metabolism is regulated by polymorphisms, which may be tested by relatively simple SNP analysis, however requiring DNA from the test individuals. Target genes for the efficiency of a given medicine or predisposition of a given disease are also subject to population studies, e.g., in Iceland, Estonia, Sweden, etc. For hypothesis testing and generation, several bio-banks with samples from patients and healthy persons within the pharmaceutical industry have been established during the past 10 years. Thus, more than 100,000 samples are stored in the freezers of either the pharmaceutical companies or their contractual partners at universities and test institutions. Ethical issues related to data protection of the individuals providing samples to bio-banks are several: nature and extent of information prior to consent, coverage of the consent given by the study person, labeling and storage of the sample and data (coded or anonymized). In general, genetic test data, once obtained, are permanent and cannot be changed. The test data may imply information that is not beneficial to the patient and his/her family (e.g., employment opportunities, insurance, etc.). Furthermore, there may be a long latency between the analysis of the genetic test and the clinical expression of the disease and wide differences in the disease patterns. Consequently, information about some genetic test data may stigmatize patients leading to poor quality of life. This has raised the issue of 'genetic exceptionalism' justifying specific regulation of use of genetic information. Discussions on how to handle sampling and data are ongoing within the industry and the regulatory sphere, the European Agency for the Evaluation of Medicinal Products (EMEA) having issued a position paper, the Council for International Organizations of Medical Sciences (CIOMS) having a working group on this issue, and the European Society of Human Genetics preparing background paper on 'Polymorphic sequence variants in medicine: Technical, social, legal and ethical issues. Pharmacogenetics as an example'. Within the European project Privacy in Research Ethics and Law (PRIVIREAL), recommendations for common European guidelines for membership in research ethical committees have been discussed, balancing the interests and assuring independence and legal competence. Good decision making, assuring legality of protocols and assessment of data protection is suggested to be part of any evaluation of protocols.

Drug Industry↗

Groundwater recharge with reclaimed municipal wastewater: health and regulatory considerations.

Groundwater recharge with reclaimed municipal wastewater presents a wide spectrum of technical and health challenges that must be carefully evaluated prior to undertaking a project. This review will provide a discussion of groundwater recharge and its management with special reference to health and regulatory aspects of groundwater recharge with reclaimed municipal wastewater. At present, some uncertainties with respect to health risk considerations have limited expanding use of reclaimed municipal wastewater for groundwater recharge, especially when a large portion of the groundwater contains reclaimed wastewater that may affect the domestic water supply. The proposed State of California criteria for groundwater recharge are discussed as an illustration of a cautious approach. In addition, a summary is provided of the methodology used in developing the World Health Organization's Guidelines for Drinking Water Quality to illustrate how numerical guideline values are generated for contaminants that may be applicable to groundwater recharge.

California↗

A modified model for projecting age-structured populations in random environments.

A discrete-time age-structured population model with vital rates linked to a stochastic environmental process was developed as a generalization of an existing model by making the explicit link between variability in the vital rates and variability in the environment more flexible. This modified model uses biologically relevant probability distributions for the vital rates, and allows for temporal autocorrelation and an arbitrary covariance structure between vital rates. Through simulations, the properties of the projected population in the short-term were investigated and compared to analytical approximations. The distribution of the total population size did not quickly approach lognormality under all conditions. Furthermore, the sensitivity of the vital rates to the environmental process had a strong effect on the variance and distribution of the projected population size. These results suggest that short-term projections need to be carried out through simulation methods, as the analytical approximations technically apply only to the long-run asymptotic behavior. Techniques for parameter estimation were considered; recommendations depend on the form of the data available. The approach described allows the empirical calculation of the probability distribution for predicted population size, a quantity relevant to the use of formal decision analysis in natural resource management.

Age Factors↗

[Auguste Lumière, pioneer of the modern cicatrization].

At the "Grand Café" in Paris, on december 28, 1895 Louis and Auguste Lumiere displayed the cinematograph, a technical innovation that revolutionized the nascent motion picture. It was the first public projection of a film. While Louis continues his work on pictures and invents autochrome plates for colour photography, Auguste focused his interests on biology and medicine. Since Ambroise Paré, few doctors have been interested in the healing process. Although Carrel and Lecomte Du Nouy published the first studies in the early twentieth century, Auguste Lumière was a pioneer in the modern research and treatment of wounds. He applied the principles of experimental medicine. In his research he used 44 dogs to study the healing speed and the scar quality in certain areas and under general conditions. In the winter of 1914-1915 he studied in Lyon several hundred wounds of war casualties. In 1922 he established and published in a marvellous book the principles of normal healing. In the department of Pr Leon Bérard he was shocked by the fetidness of the wards where the dried bandages were changed once a week. In 1915 he perfected a revolutionary sterilized "treatment-bandage" consisting of 2 mm stitched gauze saturated with Vaseline and Perou's balsam: the "Tulle Gras. In order to disinfect wounds, he used an iodized solution, sprayed in little droplets. The lives of Auguste and Louis Lumière were full of projects and inventions. When Auguste died in 1954 he had registered more than one hundred patents.

Cicatrix↗

Origin and terminal distribution of the trigeminal projections to the inferior and superior colliculi in the lesser hedgehog tenrec.

The trigemino-tectal projections were investigated with anterograde and retrograde tracing techniques in the Madagascan lesser hedgehog tenrec, Echinops telfairi. There were prominent contralateral projections to the inferior colliculus (CoI) and the superior colliculus (CoS), each showing its own characteristic pattern of terminations. While the projections to the CoI were confined consistently to a circumscribed region in its ventrolateral, external portion, the projections from particularly the rostral trigeminal subdivision to the CoS were distributed inhomogenously across almost the entire rostro-caudal and mediolateral extents. Comparing these data with the spino-tectal projections published previously, it demonstrates that the somatotopic organization of ascending tectal afferents is more distinct in the CoI than in the CoS. There were roughly twice as many trigeminal neurones projecting to the CoS than to the CoI. This difference might be due to the fact that the cells projecting to CoS were distributed extensively across the trigeminal nuclear complex (peak densities in the principal and interpolar subdivisions), while the neurones projecting to the CoI were largely confined to the interpolar and caudal trigeminal subdivisions. The latter cells were located adjacent to the spinal trigeminal tract; the neurones projecting to the CoS occupied preferentially the ventral trigeminal regions at rostral levels, while from the interpolar subdivision caudalward the labelled cells shifted dorsolaterally. In comparison to other mammals the trigeminal projection to the tenrec's CoI is unique. There is evidence for such a projection in other species too, but it is poorly documented, presumably due to technical reasons.

Animals↗

RNA interference in the pathogenic fungus Cryptococcus neoformans.

Cryptococcus neoformans is a pathogenic fungus responsible for serious disease in immunocompromised individuals. This organism has recently been developed as an experimental system, with initiation of a genome project among other molecular advances. However, investigations of Cryptococcus are hampered by the technical difficulty of specific gene replacements. RNA interference, a process in which the presence of double-stranded RNA homologous to a gene of interest results in specific degradation of the corresponding message, may help solve this problem. We have shown that expression of double-stranded RNA corresponding to portions of the cryptococcal CAP59 and ADE2 genes results in reduced mRNA levels for those genes, with phenotypic consequences similar to that of gene disruption. The two genes could also be subjected to simultaneous interference through expression of chimeric double-stranded RNA. Specific modulation of protein expression through introduction of double-stranded RNA thus operates in C. neoformans, which is the first demonstration of this technique in a fungal organism. Use of RNA interference in Cryptococcus should allow manipulation of mRNA levels for functional analysis of genes of interest and enable efficient exploration of genes discovered by genome sequencing.

Carboxy-Lyases↗

The use of cartilage grafts in primary aesthetic rhinoplasty.

Our experience with the use of cartilage grafts in 430 primary rhinoplasties is presented. We find grafts indicated when operating on small noses with thick skin to increase and define the dorsum, to add projection and angularity to the tip, to project the columella, and to correct the acute nasolabial angle. The procedure is technically simple and relatively free of complications. Long-term evaluations show no absorption of the grafts and preservation of the desired shape.

Cartilage↗

Healthy Cities: toward worldwide health promotion.

Healthy Cities is a community problem-solving process for health promotion that began in Canada and Europe in the mid-1980s. Although Healthy Cities have expanded worldwide, there is limited scientific literature that documents the effects of these efforts. This review describes the dynamic status of Healthy Cities globally and summarizes what is known about these efforts. It is difficult to draw generalizations or clear differences between Healthy Cities and other efforts with similar objectives in the United States. There appears to be less variation among Healthy Cities in Europe, most likely because of the extensive technical support provided by the WHO European Regional Office to the Healthy Cities Project. Case descriptions present the diversity and types of activities of Healthy Cities. It is concluded that community participation and broad involvement from different sectors of the community are promising approaches to addressing urban problems.

Community Participation↗

The challenges of community-directed treatment with ivermectin (CDTI) within the African Programme for Onchocerciasis Control (APOC).

The principal strategy adopted by the African Programme for Onchocerciasis Control (APOC), for the control of onchocerciasis in the 19 countries of Africa that now fall within the programme's remit, is that of community-directed treatment with ivermectin (CDTI). Halfway through its 12-year mandate, APOC has gathered enough information on the main challenges to guide its activities in Phase 2. An analysis of reports and other documents, emanating from consultants, scientists, monitors and national and project-level implementers, indicates that there are three broad categories of challenge: managerial; technical; and socio-political. Under these three categories, this review identifies the most pertinent concerns that APOC must address, during Phase 2, to enhance the prospects of establishing sustainable systems for ivermectin distribution. The major challenges include: (1) maintaining timely drug-collection mechanisms; (2) integrating CDTI with existing primary-healthcare services; (3) strengthening local health infrastructure; (4) achieving and maintaining an optimal treatment coverage; (5) establishing and up-scaling community self-monitoring; (6) designing and implementing operations research locally; (7) ensuring the adequacy of community-directed distributors; (8) increasing the involvement of local non-govemmental develop organizations in the programme; (9) achieving financial sustainability; (10) implementing equitable cost-recovery systems; and (11) engaging in effective advocacy. The implications of the challenges and suggestions about how they are being (or could be) addressed are also highlighted in this brief review, which should be of value to other programmes and agencies that may be contemplating the adoption of this unique strategy.

Africa↗

Translating research into practice: organizational issues in implementing automated decision support for hypertension in three medical centers.

Information technology can support the implementation of clinical research findings in practice settings. Technology can address the quality gap in health care by providing automated decision support to clinicians that integrates guideline knowledge with electronic patient data to present real-time, patient-specific recommendations. However, technical success in implementing decision support systems may not translate directly into system use by clinicians. Successful technology integration into clinical work settings requires explicit attention to the organizational context. We describe the application of a "sociotechnical" approach to integration of ATHENA DSS, a decision support system for the treatment of hypertension, into geographically dispersed primary care clinics. We applied an iterative technical design in response to organizational input and obtained ongoing endorsements of the project by the organization's administrative and clinical leadership. Conscious attention to organizational context at the time of development, deployment, and maintenance of the system was associated with extensive clinician use of the system.

Academic Medical Centers↗