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PubMed1990

Proposed methodology for knowledge acquisition: a study on congenital heart disease diagnosis.

This paper proposes a methodology for knowledge acquisition (KA) from multiple experts, in an attempt to elicit the heuristic rules followed by the physician in diagnosing twelve frequently occurring congenital heart diseases (CHD). Twenty-two pediatric cardiologists and twenty-three general cardiologists were interviewed with this technique; 274 interviews were conducted, 169 with the 22 experts, 105 with the 23 non-experts. A graph formalism was employed to represent their reasoning model, leading to the construction of a "mean reasoning model" for each diagnosis, separately for experts and non-experts. The results indicate that experts, compared to non-experts, tend to build knowledge representation models (KRM) that are smaller and less complex. Qualitative differences in information utilization between the two groups were also observed. Entropy analysis suggests a greater objectivity and cohesion of the experts' model.

Algorithms↗
PubMed1989

An AI-based communication system for motor and speech disabled persons: design methodology and prototype testing.

An intelligent communication device is developed to assist the nonverbal, motor disabled in the generation of written and spoken messages. The device is centered on a knowledge base of the grammatical rules and message elements. A "belief" reasoning scheme based on both the information from external sources and the embedded knowledge is used to optimize the process of message search. The search for the message elements is conceptualized as a path search in the language graph, and a special frame architecture is used to construct and to partition the graph. Bayesian "belief" reasoning from the Dempster-Shafer theory of evidence is augmented to cope with time-varying evidence. An "information fusion" strategy is also introduced to integrate various forms of external information. Experimental testing of the prototype system is discussed.

Artificial Intelligence↗
PubMed1991

Determination of the etching surface of metal frameworks in resin-bonded prostheses.

The aim of electrolytic etching of the metal framework of resin bonded retainers is a microretentive surface. The results of metal etching depend on various factors such as metal alloy, casting conditions, etching solution, and constant electrolytical conditions. Precise knowledge of the inner metal surface is necessary for an exact setting of the current density per time unit. The indirect method of copying the contours from tinfoil to graph paper reduced the error rate to a mean value of +/- 2.3 mm2. This practical method of determining the metal surface before etching can be accomplished without complicated equipment.

Acid Etching, Dental↗
PubMed2026

Network methods for diagonal integration of unpaired single-cell multiomics data: a review.

MOTIVATION: Advances in single-cell sequencing have enabled multiomics profiling at unprecedented resolution; however, mass spectrometry-based single-cell proteomics (scMS) remains inherently destructive, precluding simultaneous transcriptomic capture. Unlike antibody-based methods such as CITE-seq, which permit paired profiling but are restricted to targeted protein panels, scMS provides unbiased, genome-scale coverage of the intracellular proteome yet necessitates post hoc integration of unpaired datasets. This diagonal integration challenge, where transcriptomes and proteomes are measured in separate cells lacking shared anchors, remains underserved by existing reviews, which focus predominantly on vertical integration strategies enabled by non-destructive assays. RESULTS: We survey the complete computational pipeline for constructing mechanistic proteogenomic networks from unpaired single-cell data, covering: (i) unimodal network inference such as knowledge-based approaches, probabilistic graphical models, temporal directionality inference, and generative and foundation model strategies that establish the transcriptomic scaffold; (ii) cross-modal integration architectures such as network propagation, graph neural networks (scMRDR, scmFormer, scCotag), and consensus frameworks designed explicitly for the unpaired proteomics setting; and (iii) benchmarking paradigms spanning network reconstruction (BEELINE, GRETA, CausalBench) and multi-task integration evaluation (scMultiBench, SCMMIB), with guidance on metric selection under network sparsity and class imbalance. We identify three principal axes of future development: generative proteomic translation from transcriptomic precursors, inductive prior embedding in next-generation architectures, and perturbation-based causal benchmarking. AVAILABILITY AND IMPLEMENTATION: This is a review article; no novel software is distributed. A curated benchmark resource table, methods starter guide, and per-method bottleneck annotations are provided in the Supplementary Material.

Multiomics↗
PubMed1975

[Radioisotopic examination and diagnosis of dryness of the mouth].

The clinical and sialographic opposition between true xerostomia (with continuous disorders) and paradoxical asialia (with inter-prandial disturbance, but sparing mealtime) led the authors to analyze these patient's scintigraphic scannings. A kinetic study of excretion was carried out with gamma-camera recording of intensity and glandular activity: the information thus obtained was set down in a numerical integration block and dealt with by computer. A graph of activity was plotted for each gland showing: - a phase of ascending concentration followed by a plateau corresponding to excretion at rest; - a phase of excretion provoked by a gustatory stimulus (physiological) with a very rapidly descending graph. It is possible to establish a ratio of glandular activity/blood activity at maximum concentration and maximum excretion. From the graphs thus obtained it is possible to perfectly differentiate true xerostomia (no excretion even with stimulation) from paradoxical asialia (no plateau of excretion at rest, but stimulus effective). A better knowledge of "dryness of the mouth" should enable better adapted therapy.

Diagnosis, Differential↗
PubMed1984

Automated computer evaluation of time-varying cryomicroscopical images.

A system has been developed to perform automatic computerized recognition, tracking, and quantitative morphological analysis of viable cells in freezing solutions. Cryomicroscopical image sequences of freezing cells are digitized and analyzed by computer. Image-processing techniques are used which are insensitive to contrast fluctuations from image to image, and which perform well even in noisy, cluttered images. The generalized Hough transform is used for shape detection, and a heuristic graph-search boundary completion algorithm is applied for shape extraction. The extracted cell shape may be analyzed for changes in cross-sectional area, perimeter length, shape deformation, and other metrics of interest. Knowledge from the shape-extraction phase is used to form a prediction of what shape the cell will be in the next image frame, and thus what to look for in the next shape-detection phase. This combination of knowledge-feedback with a powerful shape-detection technique produces an automatic, dynamic shape-recognition scheme capable of accurate recognition and analysis of the cells regardless of how deformed they may become during the freezing sequence. Example performance of the system is illustrated for a series of micrographs of freezing granulocytes.

Blood Preservation↗
PubMed2025

PLNMFG: Pseudo-label guided non-negative matrix factorization model with graph constraint for single-cell multi-omics data clustering.

The development of single-cell multi-omics sequencing technologies has enabled the simultaneous analysis of multi-omics data within the same cell. Accurate clustering of these cells is crucial for downstream analyses of complex biological functions. Despite significant advances in multi-omics integration approaches, current methodologies exhibit two major limitations. First, they inadequately incorporate prior biological knowledge from various omic layers. Second, these methods often conduct independent dimensionality reduction on individual omic datasets, thereby failing to capture the intrinsic complementary information and potentially overlooking crucial cross-platform interactions. Motivated by these, this study investigates a non-negative matrix factorization model called PLNMFG, which integrates the unified latent representation learning that retains the features between and within omics and the cluster structure learning that retains the intrinsic structure of the data into one joint framework. Specially, PLNMFG performs adaptive imputation to handle dropout events and uses prior pseudo-labels as constraints during the process of collective non-negative matrix factorization, as a result, a more robust latent representation that preserves the double similarity information is obtained. Graph Laplacian constraint is applied during clustering which further preserves structure characteristic of multi-omics data. In addition, the weight of each omic is adaptively learned based on the omic contribution. A series of experiments on 8 benchmark datasets show that our model performs well in terms of clustering accuracy and computational efficiency.

Single-Cell Analysis↗
PubMedDate not supplied

Automatic derivation of initial match points for paired digital images of skin.

Computerized matching of skin images has been suggested as a means of screening for changes indicative of malignant melanoma. Matching or "registering" each lesion in a pair of images plays an important role in this process. Point-pattern matching algorithms based upon correlation or geometric transformations of the image pairs have been shown to be effective for this registration but require knowledge of one or more "initial match" points which are known to be the same on both images. A method is described for automatically finding these initial match points with a high degree of success. Our algorithm uses the so-called "Gabriel graph" representation of the paired images to select sets of probable matching points. Performance of the algorithm has been measured in realistic trials, using images of patients with large numbers of pigmented lesions. Results show that the single best match chosen is correct greater than 99% of the time, while over 93% of the first three consecutive matches will be chosen correctly. It is likely that these results can be improved through the use of additional nonpositional information or additional image processing.

Algorithms↗
PubMed2026

Evolution of maize recombination landscape during domestication.

Despite the plethora of knowledge about the benefits of meiotic recombination and numerous theoretical studies examining how recombination rates evolve, there is a general lack of empirical support and consensus across species. To fill this knowledge gap, we characterized the evolution of recombination landscape in maize during its domestication from teosinte and related the observed changes to established theoretical frameworks. Through examining recombination in experimental populations of maize and teosinte and the population genomics approach of identifying historical recombination events using ancestral recombination graph inference to generate saturated maize and teosinte recombination maps, we found that during domestication, maize experienced a 12% increase in its genome-wide recombination rate. Furthermore, maize evolved higher recombination rates on the long arms of chromosomes in regions closer to centromeres, where recombination is generally very low. The repatterning of crossover events came from changes in global crossover positioning rather than alterations in cis-acting chromatin factors. Consequently, we found evidence of selection acting on trans-acting recombination modifiers affecting crossover interference and controlling the interference-dependent class I crossover pathway. We show that CO repatterning was likely beneficial for maize fitness, as significant recombination rate increases were predominantly in gene-rich regions, which harbor domestication-related variation. This work suggests genomic and mechanistic processes leading to the evolution of meiotic recombination landscape in response to directional selection pressure and provides evidence for the evolutionary advantage of recombination.

Zea mays↗
PubMed1986

A graphical method for forecasting radiation exposure from multi-aged fallout from nuclear weapons.

After a nuclear attack it may be necessary for emergency workers, such as firemen, utility workers and medical personnel, to perform urgent tasks in areas highly contaminated by radioactive fallout. To assist the control of radiation exposure of these workers, it will be useful to provide means to forecast radiation exposures both inside and outside the fallout shelter. The method described in this paper is intended for use during the first few days to weeks after the attack, after which time more sophisticated methods may become available. This method requires only a radiation-rate meter, special graph paper, and a timepiece. Communications with Emergency Operating Centers or other sources of information are not necessary. The method permits the determination of the age of fallout and future exposure rates for a location that might be subjected to a number of different fallout clouds, without requiring knowledge of the weapon yields or times of detonation. This method will provide results with less accuracy if different-aged fallout clouds arrive simultaneously. The method is self-correcting so that if the actual decay rate is different than that which is assumed, the forecasted rates will have less error than results obtained by previous methods.

Nuclear Warfare↗
PubMed1990

A computer system for contact dermatitis: graphical representation of data.

An overview is given of the computer applications we have developed over the last twelve years in the field of contact dermatitis. The dissemination of exposure lists to sensitised individuals and the development of a knowledge-based system are mentioned only briefly. Priority here is given to the explanation of the graphical representation of the patient data collected since 1978 on 12,000 patients referred to three contact dermatitis units. More than a hundred parameters of each patient have been collected in a database. Several graphs are given of these data and are discussed in detail.

Adolescent↗
PubMed1992

Dynamics for communications data.

To create a complex dynamical model for a complex system, it is normally necessary to have a directed graph of the network, a dynamical model for each node, and a coupling function for each directed edge. But in many applications, the only observable data consists of communications from one node to another. In this situation, the modeler may infer a complex dynamical model for the network without any explicit knowledge of the independent dynamical behavior of the component systems (nodes). Here we present one procedure for this type of modeling problem, inspired by the attractor reconstruction procedure of chaos theory. Part of this proposal consists of a strategy for computer graphic presentation of the interactive dynamics of the complex system (or social network of dynamical schemes) called a netscope. We can imagine applications to diverse situations, such as decision groups, management, forecasting, international relations, classroom monitoring, therapy (personal, family, group, etc.) and distributed processors, to name a few.

Communication↗
PubMed1983

The case report. I. Guidelines for preparation.

A case report, if prepared properly, is a valuable educational device to describe an unusual clinical syndrome, association, reaction, or treatment. If a case advances basic understanding of a disorder, increases clinical skill, or suggests useful research, it is worthy of publication. Conciseness is paramount. The description of the case should contain only pertinent positive and negative findings. Irrelevant material or excessive detail can obscure the essence of a report and repel editors and readers. The discussion should emphasize the salient features of the case, show their relation to previous knowledge, interpret their significance, draw conclusions or generalizations about future cases when warranted by the evidence presented, or suggest further possible studies. Information withheld by the patient and unjustified speculation can nullify the value of a case report. Illustrations add visual appeal and enhance the educational value of a report. Tables and graphs should reduce any statistical data to readily interpretable form. All visual supplements should be simple, compact, and self-contained. Appropriate documentation is desirable, but only essential citations need be included, and the author should have carefully reviewed and verified all references used. Begin with a clear title and end with an informative Summary. A useful case report is factual, concise, logically organized, clearly presented, and readable. The three primary principles to remember: (1) Make sure the case warrants publication. (2) Include only pertinent information. (3) Be concise.

Humans↗
PubMed1979

[Activation of student cognitive activities in the process of teaching medical microbiology].

The main trends of methodical work conducted at the chair of microbiology of Orenburng Medical Institute are presented. For the purpose of activation of cognition activity of students during medical microbiology teaching the following methods were applied: presentation of the teaching material, creation of visual teaching methods in a single methodical plan in accordance with the logic structure graphs of the subject as a whole, its individual sections and themes; introduction of problem teaching method, solution of practical tasks of the II and III learning level; introduction of scientific achievements of the chair into the teaching process. Result of evaluation of the efficacy of the teaching-methodical work of the chair carried out demonstrated that knowledge of the principal microbiology problems in the students and interns persisted for long periods of time.

Cognition↗
PubMed1990

[Mortality analysis: when is single evaluation of the basic cause of death allowable, when should multi-causality be assessed?].

Data quality is often a critical point in mortality studies. The purpose of the present report is to present criteria for assessing the value of death-certificate-based mortality studies. For this purpose all 57,454 Swiss death certificates of the year 1979 were analysed. Reliability of the diagnosis listed on the death certificate was investigated by comparing for each case of a linked sample of 12,478 deaths the cause of death with medical information available from the hospital record. Retrieval rates (percentage of cases for which the given diagnosis appears in both registries) were calculated for the primary diagnoses named in each data set. These can be considered as measures of reliability of diagnoses. The graphs given indicate a high reliability for cancers and accidents. Reliability was lower for other causes of death such as cardiovascular diseases, diabetes mellitus, rheumatic diseases. Restriction to the primary cause of death can be accepted for most cancers, accidents and violent deaths. For other causes of death, decisions must be made individually and multicausal analysis may be indicated. In addition, knowledge of the reliability of the diagnoses of interest is necessary for the interpretation of results derived from death certificate-based mortality studies.

Cause of Death↗
PubMed2026

Genomic insights into natural selection in recent human history.

For over a century, scientists have debated the extent to which genetic and phenotypic variation among present-day humans is the result of natural selection - in which heritable traits influence survival or reproduction - versus neutral processes such as genetic drift or population history. The initial sequencing of the human genome and subsequent population resequencing studies enabled genome-scale searches for signatures of selection in present-day genomes. This first generation of genome-wide selection scans identified many targets but left open questions about the timing and nature of selection, making it challenging to identify environmental and biological drivers. Recent methodological advances based on reconstructing ancestral recombination graphs have increased the potential power and resolution of selection scans based on present-day genomes, while the availability of new data on ancient DNA has facilitated the direct reconstruction of genetic change through time. However, there is little consensus on how to use these data to detect and interpret signatures of selection, while avoiding confounders. Here, we review the current state of knowledge about the impact of selection on human genomic diversity and highlight conceptual advances in our understanding of human evolution over the past 10,000 years.

Journal Article↗
PubMed1976

Lateralization in stroke syndromes as a factor in ambulation.

Lateralization should not be ignored in any rehabilitation program for patients with stroke syndromes. Despite the known differences resulting from the localization in the dominant versus the nondominant hemisphere (spatial perception, speech, etc.), practical application of this knowledge in gait training is sparse. The authors looked into different stages of ambulation and the time sequence between these stages and the onset of disease. Standing and walking in parallel bars and outside, as well as elevation activities were given numerical values in an effort to assess abilities quantitatively. The assessment of each patient was recorded graphically (stage of gait against time) and then the different graphs were summated in order to form a common right hemiparetic versus left hemiparetic curve. This study of 236 out of 298 patients (129 left hemiparetics and 107 right ones) showed the following: (1) The right hemiparetics progressed more rapidly in all stages of ambulation, statistically significant figures being obtained for the first two stages; (2) a greater percentage of right versus left hemiparetics reached the assigned levels of ambulation: and (3) 89% out of the 236 patients included in our study were able to ambulate in parallel bars, 81% outside the bars and 38.5% were proficient in stair climbing. Out of the original total number of patients (298), 64% were able able to ambulate outside the bars.

Adolescent↗
PubMed1991

A laser densitometer for selective spot analysis on dot blots and two-dimensional gel autoradiograms.

We describe an inexpensive densitometer, employing a small HeNe laser and an IBM-compatible personal computer that performs accurate measurements of selected spots on two-dimensional gel autoradiograms or chromatograms with an accuracy and a sensitivity equal or superior to those of many commercial instruments. Our open-table design allows the operator to visually monitor the scanning process in room lighting, and provides great flexibility in both the size and the nature of items to be scanned. The instrument has two moving parts (a prism and a small motor). A commercially available software package (ASYST) acquires digital data, graphs the data on the TV monitor, converts the data to optical density or to radioactive incorporation (cpm), subtracts background, integrates peak areas, and stores data on disk. The total time for these operations is 20-30 s per spot. The instrument has a dynamic range of 0.25 to 3.0 OD units and can measure a 10,000-fold range of 14C or 35S isotope concentrations on autoradiograms. The complete device can be assembled with a hobbyist's knowledge of electronics, moderate programming abilities (no machine language required), and a cost of less than $3000, not including the IBM PC.

Costs and Cost Analysis↗