Adult Test Subjects Research Articles

Mathematical Ranking of AI Classifiers Using Confusion Matrix and Matthews Correlation Coefficient

This research primarily deals with mathematically ranking the level of accuracy of various Artificial Intelligence (AI) based machine learning classifiers, using Mathews Correlation Coefficient (MCC), leveraging Confusion Matrices. A detailed Literature survey was done to gather the existing knowledge. This knowledge was used as foundational basis to further build the scope of this research project. The classifiers used were Support Vector Machine (SVM), K-Nearest Neighbors (KNN), and Convolutional Neural Network (CNN). These classifiers were used for Face recognition of individuals. A total of 33 adult test subjects with 10 images per subject resulting in a total of 330 distinct images were part of this research project. These test subjects were from the Labeled Faces in The Wild publicly available database along with teachers from James B. Conant High School who voluntarily participated in this research. Python based face recognition program wrappers and associated environment was built around pre-existing classifiers and the image data was passed to these wrappers. These wrappers recognized the faces of individuals in the images over 10 trials wherein each trial consisted of 33 distinct images, with varying degree of accuracy and presented that as outputs. These outputs were used to determine the Confusion Matrices which in turn were used to calculate the MCC scores. The MCC scores were plotted, and these results showed that the SVM AI classifier had the highest level of relative accuracy for face recognition, followed by KNN and CNN classifiers.

Synthesis of isognostic text images for visual performance evaluation

Subject of study. Principles and technologies for synthesis of test letter charts and standardization of measurements of reading parameters for evaluation of visual performance in the reading process, which is the most important type of human visual activity, are the subjects of the study. Aim of study. The study was aimed at developing a synthesis algorithm for textual isognostic images for quantitatively evaluating reading parameters as indicators of the state of visual performance that ensure the correlation between optical and semantic properties based on optical and optometric standards. Methods of study. A set of test images in the form of texts was created using digital methods for image synthesis. The text images were standardized for measuring reading parameters using optometric methods. Main results. A set of texts was synthesized and standardized considering the complexity and number of symbols in words, the frequency of occurrence and average width of Russian letters, the lengths of sentences, the angular sizes of characters, and the contrast. The text was standardized according to the angular visual acuity and conventional optometric standard ISO 8596, 2009. The synthesized test images comprised sets of text fragments of similar numbers of characters but different angular sizes. The sizes of the characters were correlated with the threshold angular values characterizing visual acuity according to optometric standards. The maximum reading speed, critical print size, and reading acuity were measured in 29 healthy adult test subjects to assess the reproducibility of results obtained using the synthesized test images. The measurements were performed twice for each test subject using two different charts synthesized using the developed method. No statistically significant difference was observed between the measurement results, which indicated good reproducibility of the results obtained using this test. Practical significance. The proposed algorithm for synthesis of standardized texts for assessing reading parameters is the simplest general method for a broad application in routine effectiveness evaluation of the therapy of macular zone pathology and lens fitting for short working distances.

Forces Required for Isolated Malleus Shaft Fractures.

Background and Hypothesis:Isolated malleus shaft fractures are rare cases. A commonly reported cause is a finger pulled out from a wet outer ear canal after a shower or bath. The objective was to investigate experimentally the mechanism and forces needed to establish an isolated malleus shaft fracture.Methods:Ten fresh-frozen human temporal bones were adapted to allow visual inspection of the structures involved while negative pressure trauma was applied. Thirty malleus bones were broken and the required forces were measured. Measurements from 60 adult test subjects were used to create mathematical and physical models to calculate and measure the forces necessary for generating trauma. To calculate the maximum muscle force developed by the tensor tympani muscle, the muscle area and fiber type composition were determined.Results:The temporal bone experiments showed that applied negative pressure in a wet ear canal could not fracture the malleus shaft with only passive counterforce from supporting structures, although the forces exceeded what was required for a malleus shaft fracture. When adding calculated counteracting forces from the tensor tympani muscles, which consisted of 87% type II fibers, we estimate that a sufficient force is generated to cause a malleus fracture.Conclusion:The combination of a negative pressure created by a finger pulling outward in a wet ear canal and a simultaneous counteracting reflexive force by the tensor tympani muscle were found to be sufficient to cause an isolated malleus fracture with an intact tympanic membrane.

Zoster patients on earth and astronauts in space share similar immunologic profiles

BackgroundOn long-duration spaceflight, most astronauts experience persistent immune dysregulation and the reactivation of latent herpesviruses, including varicella zoster virus (VZV). To understand the clinical risk of these perturbations to astronauts, we paralleled the immunology and virology work-up of astronauts to otherwise healthy terrestrial persons with acute herpes zoster. MethodsBlood samples from 42 zoster patients – confirmed positive by PCR for VZV DNA in saliva (range from 100 to >285 million copies/mL) were analyzed for peripheral leukocyte distribution, T cell function, and plasma cytokine profiles via multi-parametric flow cytometry and multiplex bead-based immune-array assays. Patient findings were compared to normal value ranges specific for each assay that were defined in-house previously from healthy adult test subjects. ResultsCompared to the healthy adult ranges, the zoster patients possess (1) a higher proportion of constitutively activated T-cells, (2) a T-cell population skewed towards a more experienced maturation state, (3) depressed general T-cell function, and (4) a higher concentration of 20 of 22 measured plasma cytokines. DiscussionThe pattern of immune dysregulation in zoster patients is similar to that of astronauts during spaceflight who shed VZV DNA in their saliva. Because future deep space exploration missions will be of an unprecedented duration, prolonged immune depression and chronic viral reactivation threaten to manifest overt disease in exploration class astronauts.

The oral mucosal surface and blood vessels

IntroductionDetailed information about the size of the oral mucosa is scarce in the literature, and those studies that do exist do not take into account the size of the tongue or the enlargement of the surface by the papillae. Because of the various functions of the oral mucosa in the maintenance of oral health, knowledge of its true size may provide a better understanding of the physiology of the oral cavity and some oral diseases and direct future therapeutic strategies. The aim of this study was to determine the total size of the oral mucosa.MethodsFive human adult cadaver heads were cut in the median sagittal plane, and the total area of the oral surface was determined using silicon casts. The surface of the tongue was measured with quantitative profilometry. Photographs of oral blood vessels were taken in different areas of the oral mucosa of adult test subjects using intravital microscopy, and the pictures were compared with vessel casts of the oral mucosal capillaries of a maccaca fasciculrais monkey, which was studied using a scanning electron microscope.ResultsThe results showed that the dorsal side of the tongue comprises a large proportion of the total oral mucosal surface. The surface area of the epithelium increases moving from anterior to posterior on the tongue, and the number of underlying blood vessels increases proportionally.ConclusionsIt can be concluded that the back of the tongue plays an important role in the oral resorption of drugs. Clinical relevance: The results may be of relevance for the delivery and development of oral drug application.

Auditory testing profiles of Pelizaeus-Merzbacher disease.

To characterize the auditory manifestations of patients diagnosed with Pelizaeus-Merzbacher Disease (PMD), a rare X-linked disorder of myelin classically characterized by nystagmus, spastic quadriparesis, ataxia, and cognitive delay in early childhood or progressive disease in adulthood. A prospective case study of 5 pediatric and 3 adult patients diagnosed with PMD who demonstrate varying degrees of abnormal auditory function. These patients underwent comprehensive audiological evaluations (audiometry, tympanometry, otoacoustic emissions), auditory processing tests (Dichotic Listening, Frequency Pattern Test, Duration Pattern Test), and electrophysiological measures (Auditory Brainstem Response). Abnormal electrophysiological findings with normal cochlear function were found in all test subjects. Further testing completed on adult subjects revealed further central auditory dysfunction via auditory processing tests. All the adult test subjects had abnormal results on auditory processing tests including significant left ear deficits on dichotic digits and poor duration pattern test scores. Auditory processing test results indicated strong right ear advantages for all adult PMD test subjects in Dichotic Digit testing. The degree of audiological central dysfunction findings was more severe in subjects with greater symptoms of the disease. Our findings indicate the need for a full audiological test battery on all patients with Pelizaeus-Merzbacher disease and other severe neurological disorders.

Systemic Interaction of the Cortical Areas during Performance of Verbal–Mnestic Activity

The dynamics of the interregional interaction of cortical areas was studied in adult test subjects who accomplished the tasks of listening to and memorizing a poem and of mental arithmetic. Analysis of the spatial and temporal relations of the oscillations of the brain biopotentials showed the participation of many regions of the left and right hemispheres in the verbal–mnestic activity. The interaction was most expressed between the posterior regions of the left hemisphere and the anterior regions of the right one. To find out whether these data agree with the classical concepts on the leading role of the left hemisphere in speech activity, the authors examined 3- and 4-year-old children with motor alalia. A comparison of 3-year-old alalics with the control group of healthy children of the same age demonstrated a marked weakening of the distant interaction of the activity of the ipsilateral antero- and posterotemporal regions of the left hemisphere (i.e., those that correspond to the Broca area and Wernicke zone) both between themselves and with the activity of other cortical regions of both hemispheres. These results confirm the important role of both the inter- and intrahemispheric relations, especially those between the Broca area and the Wernicke zone, in realizing verbal–mnestic functions. A significant weakening of the systemic interaction between EEG oscillations in these areas in alalic children suggests that the auditory feedback plays a special role during speech production in the ontogenetic development of the neurophysiological mechanisms that are responsible for speech function formation.

Computerized Measurement of Speech Intelligibility I.: Development of System and Procedures

An experimental system for the measurement of speech intelligibility has been developed. It uses a Personal Computer (PC), together with appropriate software to handle playback of test words in carrier phrases, presented in a 'closed response' test condition. Information about the intelligibility, based on the correct responses and the confusions, is immediately available due to simultaneous collecting and sorting of subjects' responses. The system works satisfactorily and reliably and has been well received by experimenters as well as by adult test subjects in the age range 18-70 years. From a new Danish standard speech material for audiological purposes, a Multiple Choice speech intelligibility test has been devised. The test is called 4AFC (Four Alternative Forced Choice) and is based on monosyllabic words with consonant confusions. Normative data for the 4AFC test, obtained with the computerized system, are presented in an accompanying paper.

Fractional gastrointestinal transit time

The intra- and interindividual variation in the gastrointestinal transit times was measured in 12 healthy adult test subjects using a scintigraphic method with 111In marked single unit tablets. Test conditions were semi-standardized. The variation within the same individual was as large as the variation between different subjects regarding the transit times through both the small and the large intestines. The small intestine transit time was 5 h (median) with an interquartile range of 4-7 h. The median transit time through the large intestine was 23.5 h (interquartile range 19.0-40.5 h). The coefficient of repeatability for the small intestinal and large intestinal transit time was 4 h and 33 h respectively. Our conclusion is that the 111In single unit capsule method can be used for measuring the fractional gastrointestinal transit times, but the intra- and interindividual variations are rather large and similar. From a radiation-hygienic point of view the 111In single unit capsule method is acceptable. The large inter- and intraindividual variation in gastrointestinal transit time might be an important factor in the absorption of certain drugs.

Predicted Deposition of Nonhygroscopic Aerosols in the Human Lung as a Function of Subject Age

A predictive aerosol deposition model, which has been validated by comparison with experimental data from adult test subjects, is used to study particle deposition patterns within the developing human lung. Here, an age-dependent lung morphology is presented in which the growth of bronchial airway dimensions is described by the measurements of Phalen et al. (1985), and the number and sizes of pulmonary airways are derived from Dunnill (1962). Total, and compartmental tracheobronchial and pulmonary deposition fractions are calculated for different breathing patterns, from sedentary to maximal activity, and particle sizes ranging over three orders of magnitude. The influences of human subject age and physical activity levels upon regional aerosol deposition within the developing lung are complex; systematic patterns, however, can be identified which are consistent with the effects of linear airway dimensions and particle flow characteristics upon effective particle deposition mechanisms.

Pharmacokinetics of Salicylate Elimination in Man

Salicylate elimination kinetics was studied over a dose range of from 0.25 to 2.0 Gm. of aspirin. It was found that when the amount of salicylate in the body of normal adult test subjects exceeded approximately 360mg. aspirin equivalent, conjugation of salicylic acid with glycine reached a maximum rate and thus proceeded by zero-order kinetics. The over-all elimination of salicylate was found to proceed by first-order kinetics at very small doses, and by parallel zero and first-order processes at higher doses. A kinetic model was developed, and values for appropriate rate constants were determined which make it possible to reconcile apparent half-lives for salicylate elimination ranging from about 3hr. to over 20hr. which have been reported in the literature. Unusual patterns in salicylate elimination kinetics observed by others, such as a change from zero to first-order kinetics upon concomitant administration of <i>p</i>-aminobenzoic acid, and zero-order elimination in a newborn infant, have been rationalized and interpreted by means of the kinetic model evolved from the present study. The pharmacokinetics of salicylate elimination were found to be unusual both qualitatively and quantitatively, and the results of the present study have potentially important therapeutic, toxicologic, and pharmacogenetic implications.