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The definition of the usefulness of the binary classifier from the point of view of reducing the a priori risk of false classification is formulated. Sufficient conditions are proposed to guarantee the utility of a diagnostic test according to this definition. The obtained conditions improved the traditional ROC analysis by limiting the corresponding region of the ROC curve. The line limiting the region of the guaranteed useful test is shown to coincide with the known iso-performance line corresponding to the a priori risk level. The feasible limits of the ratio of losses from target misses and false alarms were determined, according to which a test with appropriate operational characteristics remains useful for screening a disease with a known prevalence. Based on the obtained results, the authors substantiated the efficiency of the new method of the analysis and interpretation of electrocardiograms, which is based on determining the original diagnostic feature in the phase space and enables detecting persons with a high risk of coronary heart disease in the early stages of the disease. [ABSTRACT FROM AUTHOR]

The definition of the usefulness of the binary classifier from the point of view of reducing the a priori risk of false classification is formulated. Sufficient conditions are proposed to guarantee the utility of a diagnostic test according to this definition. The obtained conditions improved the traditional ROC analysis by limiting the corresponding region of the ROC curve. The line limiting the region of the guaranteed useful test is shown to coincide with the known iso-performance line corresponding to the a priori risk level. Permissible limits of the ratio of losses from target misses and false alarms were determined, according to which a test with appropriate operational characteristics remains useful for screening a disease with a known prevalence. Based on the obtained results, the authors substantiated the effectiveness of the new method of the analysis and interpretation of electrocardiograms, which is based on determining the original diagnostic feature in the phase space and enables detecting persons with a high risk of coronary heart disease in the early stages of the disease. [ABSTRACT FROM AUTHOR]

Background. Reliable operation of in-core neutron detectors improves the quality of measurement data processing and make fields of the neutron and power distributions in the nuclear reactor core more efficient. Materials and methods. The article discusses a new method for monitoring the technical condition of self-powered neutron detector (SPND) that is used to measure neutron flux in the nuclear reactor core. The method is based on the measurement of current values of the detector measuring circuit under steady and dynamic conditions. To monitor the state of this neutron detector, it is proposed to determine not only the insulation resistance of the measuring cable, as it is done in traditional methods, but also the generating capacity of the detector emitter. In addition to the given diagnostic parameters, a new diagnostic feature of the controlled object – capacitance of the measuring circuit of the reactor – has been is introduced in this article. Results and conclusions. Determination of the generating capacity of SPND emitter significantly (by 3–4 orders of magnitude) extends the operating range of the detector by the permissible insulation resistance value (less than 106 Ohms). At the same time, we obtain a new method to estimate the degree of electron emitter burnup caused by neutron flux and to monitor the technical condition of detector by the magnitude of its sensitivity to this flux, which increases the reliability of SPND. Determining the capacitance of the measuring cable of the electrical circuit allows you to properly consider this value when measuring the current signal of the activation detector in order to find the reactor neutron flux under the transient modes of operation.

Issues of ensuring the accident-free transition of an autonomous electric-power system to a partially inoperable state caused by the failure of working generator units are considered. The processes occurring in the network during the transition of one of the sources of electricity to the motor mode are investigated. It is shown that the time delay in the formation of a signal to turn off a failed unit operating with reverse power may not only contribute to the development of a defect in the primary motor, but also lead to an emergency situation associated with loss of controllability. The problem of shutting down a faulty source of electrical power and reducing the load of the network until the moment of overloading the generating units that remained operational is formulated. A diagnostic feature is proposed that allows identifying the inoperable state of the generating unit during its operation. An approach has been developed that implements a method of preventive control of an autonomous electric-power system in the event of failure of its elements. An algorithm is proposed that provides preventive protection of the system against reverse power, which predicts the modes of its operation in the event of an emergency situation. At the same time, structural adaptation is provided, which excludes an emergency situation associated with an interruption in the power supply to the system, and makes it possible to increase its reliability and safety. [ABSTRACT FROM AUTHOR]

The male of Euphyia vallantinaria (Oberthür, 1890) has been recorded for the first time from the Iberian Peninsula and its genital morphology has been described and illustrated. DNA barcode data are presented and compared with the other European Euphyia species.

Background. The article discusses the construction of mathematical models of controlled objects based on the fundamental laws of classical mechanics for solving the main problem of technical diagnostics – determining the technical condition. Materials and methods. A diagnostic model is built on the basis of a mathematical model. This approach leads to the definition of the working functions of the object and the receipt of criteria for assessing the performance required determining the residual resource. The concept of a diagnostic feature of an object to be identified in the process of diagnostics is clarified. Results and conclusions. In this article, consideration of the issues of technical diagnostics is limited to objects of a mechanical nature.

Background. When solving problems of technical diagnostics, experimental information is used, which is obtained with one or another accuracy, determined by the measuring equipment. To assess the technical condition of the controlled object, it is necessary, based on the measurement results, to identify those structural parameters of the object that are defined as its diagnostic features. Materials and methods. The values of these parameters will be found with some uncertainty associated with the accuracy of the results of direct measurements. The article discusses the dependence of the reliability of the results of technical diagnostics on the accuracy of the results of direct measurements. The used diagnostic equation represents a sequence of elementary diagnostic transformations. Results and conclusions. The initial relations for estimating the probability of correct diagnosis and the probabilities of errors of the first and second kind are given.

The object of research is the degradation processes that take place in gas-pumping units (GPU) during its long-term operation and lead to the appearance of defects and, as a result, to a change in its technical state. Today, methods of parametric and vibration diagnostics are used to determine the technical condition of the GPU. To identify diagnostic signs of the technical state of the GPU, various transformations are used, in particular the wavelet transforms used in vibration processing that accompany the operation of the GPU and their technological parameters. At the same time, in the study of the diagnostic signs of the technical state of the GPU, the acoustic processes accompanying the operation of the GPU, which can be more informative in comparison with the vibration ones, were practically not considered. The developed experimental research methodology and their technical support made it possible to record the acoustic processes accompanying the operation of the gas compressor unit type GTK-25-i of the Nuovo Pignon company (Italy). In the course of the experimental studies, the realizations of the acoustic processes of the GPU were obtained for its three states – «nominal», «defective» and «current». Further studies of acoustic processes for three states of the GPU type GTK-25-i and using the wavelet transform showed that by the appearance of the wavelet spectrograms it is difficult to notice the difference in the appearance or disappearance of various frequency components depending on the technical state of the GPU. To obtain quantitative indicators of this dependence, a discrete wavelet transform was carried out, which makes it possible to identify characteristic trends in the change in noise values at different scales. The values of the approximation norm and the detail norms in relation to the signal norm (in percent) were obtained for a five-level wavelet decomposition with datasets. A linear dependence of the norm of the wavelet-component of the fifth-order detailing on the operating time of GPU type GTK-25-i and (changes in the technical state), which can be taken as a diagnostic sign of its technical state, has been established. The investigated diagnostic feature can be used as the basis for the method of diagnosing the technical state of GPU type GTK-25-i based on the characteristics of its acoustic process using the wavelet transform. An approach to identifying a diagnostic sign of the technical state of a GPU type GTK-25-i is considered based on the characteristics of acoustic processes using a wavelet transform can be used to identify a diagnostic sign of a condition for any type of GPU. [ABSTRACT FROM AUTHOR]

Species belonging to genus, Thysanoplusia Fabricius of the subfamily Plusiinae which are polyphagous in nature and pest of vegetables, foods, legumes, fodder, fruits, ornamental plants and cotton crops. Samples were collected from different localities of district Bahawalpur. For collection, comprehensive and comparative surveys were carried out during 2017–18 on taxonomic account of species of the genus Thysanoplusia Fabricius and resulted identified one species Thysanoplusia orichalcea (Fabricius) first time from Pakistan. Morphological characters viz., vertex, frons, labial palpi, antennae, compound eyes, ocelli, proboscis, wing venation, male and female genital characteristics were used for the identification and classification. Dichotomous keys and photographs are also provided. There is hardly any substantial research work on taxonomic studies of subfamily Plusiinae Pakistan. So to fill this gap the present proposal was designed to study the diversity of Noctuid moths from Pakistan and very fruitful results have been obtained. [ABSTRACT FROM AUTHOR]

The failure of high-power synchronous motors leads to significant financial losses. This is of great importance for synchronous generators operating in high-power electrical networks and having an effect on a great many consumers. Sudden failure of the high-power generator results in heavy fines and repair costs, malfunction of the power-supply systems, and electric users. Troubleshooting of the equipment is aggravated by many interrelated factors. The method of measuring the external electromagnetic fields, which is widely used for the induction motors, is not used in practice for synchronous machines. Installation of field sensors inside the synchronous machine is not always possible, and measurement of external fields has weak methodological and factual bases. Simulation of the synchronous machine allows tracing the connection of a particular defect with the distortion of the external electromagnetic field of the machine. Full-scale experiments show the actual feasibility of measuring the magnetic fields in the off-synchronous generator housing. Investigation of an external electromagnetic field's connections with specific machine defects, development of field measuring procedures and processing of the measurement result, and uncovering the diagnostic properties characterizing the state of an operating synchronous machine and allowing making a required decision, is an important scientific and technical issue. [ABSTRACT FROM AUTHOR]

Electromagnetic vibration disturbing forces in different variants of the rotor displacement from an axis of the stator bore is carried out. Investigation for ТG type ТGV-200-2 by finite element method in COMSOL Multiphysics is carried out. The field mathematical model of static and dynamic eccentricity is described. The amplitude vibration disturbing forces are greatest, when a static eccentricity direction coincides with an axis of the stator winding phase is shown. The diagnostic features static and dynamic eccentricities are formulated. The most value of forces in the point with minimal air gap is shown. The diagnostic features static and dynamic eccentricities and the method of diagnostic eccentricity are formulated. Diagnostic feature of static eccentricity is to change the amplitude Maxwell stress tensor is established. The dynamic eccentricity diagnostic features are appearance in the spectrum of vibration disturbing forces rotating and multiple harmonics.

A new locality of Macrosciadium alatum in the Western Bieszczady Mts. (Duszatyn, Komańcza district, Sanok county) is described in this paper. The locality is currently the westernmost point of distribution of the species. As Macrosciadium alatum is an invasive species, it is advisable to monitor it cyclically in this area. A newly discovered diagnostic feature of this species, not included in descriptions of this plant so far, is conically elongated cells, i.e. papillae on the upper side of the petals. It is suggested that this feature be used in the identification of representatives of the Apiaceae family in Poland and Europe. The distribution map of the species has been updated in this work.

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Purpose: The characteristic features of prematurely fused craniosynostosis in plain radiographs have already been described in literature, but there is no clinical trial investigating the individual features of every single form of craniosynostosis. We described suture-specific characteristics as well as its frequency of appearance in plain radiographs in every different form of craniosynostosis. Intraoperative findings served as control to confirm the diagnosis. Methods: One hundred twenty-seven children with prematurely fused cranial sutures who underwent a skull X-ray from 2008 to 2012 were investigated in the present study. In detail, 34 children with frontal, 60 with sagittal, 13 with unilateral and 14 with bilateral coronal synostosis and 3 with unilateral lambdoid craniosynostosis as well as 3 children with a bilateral lambdoid synostosis were included. Results: Typical radiological characteristics in craniosynostosis exist. These features as well as its frequency in craniosynostosis in plain skull radiographs are presented. In all cases, these typical features enabled a correct diagnosis, which was confirmed by intraoperative findings. Conclusion: The frequency of the appearance of typical features is listed and may serve as a 'mental internal check list' in the radiological approach to craniosynostosis. The study points out the value of plain skull X-rays as it enabled proper diagnosis in all investigated 127 cases. [ABSTRACT FROM AUTHOR]

In this study, coupled Computational Fluid Dynamics (CFD) and Computational Heat Transfer (CHT) unsteady simulation was employed to study pulsatile blood flow through the infrarenal aorta and the subsequent bioheat transfer effects on the temperature profile on the midriff skin surface. It was observed that a thermal elevated feature was present on the midriff abdomen surface for the Abdominal Aortic Aneurysm (AAA) case while the temperature contours for the healthy aorta model were uniform. The temperature values of the thermal elevation differ from its immediate surroundings by 0.04K. An experiment was also conducted to validate the CFD simulation results, and it showed similar thermal elevation trend at the surface of the phantom. These findings are helpful to correlate the presence of an AAA to the thermal features on the midriff skin surface qualitatively and pave the way to potentially render Infrared Thermography a viable AAA diagnostic tool. [Display omitted] • This study correlates the presence of Abdominal Aortic Aneurysm (AAA) with temperature profile on midriff skin surface. • Perform pulsatile CFD/CHT coupled simulations of patient-specific AAA and idealised healthy aorta 3D models. • AAA results show a thermal elevation on the midriff skin surface that is 0.04K higher than its surroundings. • An experiment is conducted which validated the simulation results qualitatively. • The findings pave the way to make Infrared Thermography a viable tool to diagnose AAA. [ABSTRACT FROM AUTHOR]

As is well known, the information entropy is a basic notion in cybernetics. This paper mainly summarizes some applications of information entropy in our machinery diagnostic research practice. First, we use it as a quantitative measure of equipment diagnostibility, maintainability. Second, we introduce a criterion of complexity in frequency domain to evaluate the complexity of diagnostic signal in rotating machinery. Then a new criterion called the index of orbit complexity is proposed to evaluate the dynamic quality of rotor systems during their operation. Finally the entropy distance is applied as an effective diagnostic feature to discriminate the potential faults inside the operating machinery. Practical case studies and experiments show its effectiveness. [Copyright &y& Elsevier]

Intestinal neuronal dysplasia (IND) is an intestinal motility disorder, which clinically resembles Hirschsprung's disease (HD). Adventitial fibromuscular dysplasia (AFMD) consists of proliferation of smooth muscle cells and collagen fibers in the adventitia of blood vessels. The purpose of this study was to investigate vascular abnormalities in large bowel biopsies from patients with isolated HD, IND associated with HD and isolated IND. Large bowel biopsies from patients presenting with isolated HD ( n=23), IND associated with HD ( n=11), isolated IND ( n=16) and normal bowel as controls ( n=6) were investigated using acetylcholinesterase (AChE) histochemistry, van Gieson staining and alpha-smooth muscle actin (alpha-SMA) immunohistochemistry. Increased AChE activity around submucosal vessels was found in 9/16 (56%) cases with isolated IND, 3/11 (27%) cases of IND associated with HD, 5/23 (21%) isolated HD cases and 0/6 controls. AFMD was found in 10/16 (62%) of the isolated IND cases, 4/11 (362) of the cases with IND associated with HD and 4/23 (17%) cases of HD without IND using van Gieson staining. None of the control specimens revealed AFMD. Increased alpha-SMA immunoreactivity filaments were demonstrated in the submucosal vessel wall in 9/16 (56%) of isolated IND and 2/11(18%) of IND associated with HD cases. Normal alpha-SMA immunoreactivity around submucosal vessels was seen in isolated HD and controls. Abnormal submucosal vasculature is a common histological finding in isolated IND and IND associated with HD and may be a useful additional diagnostic feature in these patients. [ABSTRACT FROM AUTHOR]

Background: Hair is one of the most common evidence types found in criminal investigations. Analysis of human hair reveals the mineral composition accumulated within it over time spent in a specific area, thereby providing additional information for forensic identification.Materials and Methods: To identify patterns of the elemental composition of hair in territories with different natural and anthropogenic features, hair samples of 1238 residents and 217 corpses of Central Kazakhstan were studied. The determination of 14 chemical elements in hair by inductively coupled plasma atomic emission spectrometry were presented. The data were analysed in terms of place of residence, gender, age and condition.Results: The results showed that the concentration of trace elements like Cu, Fe, Cd, and As significantly differed among all regions (p < 0.05). The composition of hair samples obtained from women significantly differed from those obtained from men for certain major and trace elements (p < 0.05). Concentrations of Ca and Mg in men were significantly lower than in women (p < 0.05) and were decreasing with age (p < 0.05).Conclusions: The present investigation revealed a relationship between the elemental composition of hair and the place of permanent residence of a person, formed under the influence of regional industrial complexes, and determining gender and age-related differences. These findings enhance the possibilities of forensic human identification. [ABSTRACT FROM AUTHOR]

The atrial high rate episode diagnostic in the Thera® pacemaker reports frequency, duration, and date/time of atrial tachyarrhythmias according to programmed criteria. The aim of the study was to validate the atrial high rate episode diagnostic feature. Episodes of atrial fibrillation recorded by Holter monitoring were compared to episodes detected by the pacemaker. Forty five ambulatory (Holter) recordings were used for evaluation. Thirty of 45 ambulatory (Holter) recordings showed sinus rhythm. On 4 of these 30 ambulatory (Holter) recordings, the Thera® detected 12 episodes of atrial tachyarrhythmias as false-positives (sinus rhythm was detected as atrial tachyarrhythmia). The main reason was far-field R and T wave oversensing. On 15 of 45 ambulatory (Holter) recordings, 125 episodes of atrial tachyarrhythmias were recorded. Ninety-three of these events also were detected by the pacemaker, while for 32 events the Thera® reported sinus rhythm. The main reason was that the episodes were of too short duration. Therefore, the Thera® (programmed with detection rate 160 beats/min, detection beats 40, termination beats 10) was unable to detect atrial tachycardias. Software simulation of the diagnostic algorithm under several programming settings using the digitized Holter files demonstrated highly reliable detection of atrial tachyarrhythmias (sensitivity 98%, specificity 100%) when programmed as follows: detection rate 220 beats/min, detection beats 10, termination beats 20. It can be concluded that Thera®'s high rate episode monitor is a reliable tool for detection of atrial tachyarrhythmias, if programmed as recommended. [ABSTRACT FROM AUTHOR]

The diagnosis and management of infants and children with a significant viral lower respiratory tract illness remains the subject of much debate and little progress. Over the decades various terms for such illnesses have been in and fallen out of fashion or have evolved to mean different things to different clinicians. Terms such as "bronchiolitis," "reactive airways disease," "viral wheeze," and many more are used to describe the same condition and the same term is frequently used to describe illnesses caused by completely different dominant pathologies. This lack of clarity is due, in large part, to a failure to understand the basic underlying inflammatory and associated processes and, in part, due to the lack of a simple test to identify a condition such as asthma. Moreover, there is a lack of insight into the fact that the same pathology can produce different clinical signs at different ages. The consequence is that terminology and fashions in treatment have tended to go around in circles. As was noted almost 60 years ago, amongst pre-school children with a viral LRTI and airways obstruction there are those with a "viral bronchitis" and those with asthma. In the former group, a neutrophil dominated inflammation response is responsible for the airways' obstruction whilst amongst asthmatics much of the obstruction is attributable to bronchoconstriction. The airways obstruction in the former group is predominantly caused by airways secretions and to some extent mucosal oedema (a "snotty lung"). These patients benefit from good supportive care including supplemental oxygen if required (though those with a pre-existing bacterial bronchitis will also benefit from antibiotics). For those with a viral exacerbation of asthma, characterized by bronchoconstriction combined with impaired b-agonist responsiveness, standard management of an exacerbation of asthma (including the use of steroids to re-establish bronchodilator responsiveness) represents optimal treatment. The difficulty is identifying which group a particular patient falls into. A proposed simplified approach to the nomenclature used to categorize virus associated LRTIs is presented based on an understanding of the underlying pathological processes and how these contribute to the physical signs., (Copyright © 2020 Douros and Everard.)