556 research outputs found

    Mechanics and Mathematical Modeling of Class III Treatment with Orthodontic Appliances with a Movable Ramp

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    Treatment of class III is a current problem in orthodontics that requires constant improvement of its methods, development of new or modifications of known methods and techniques. We have developed and studied the modification of removable functionally-directing orthodontic appliances for treatment of Class III, which consists of a plastic base, vestibular arc, retaining clasps, ramp, which is connected with the base by means of two torsion springs. Its usage ensures a prolonged contact of ramp with the teeth. We studied two types of club-shaped springs (torsion springs): one spring, which create an amortization effect during the action of the ramp, but do not change its inclination angle and second one – spring that seek to increase the angle of the ramp inclination due to the disclosure of its curl

    Three-Dimensional Ultrasonography for the Evaluation of Atherosclerotic Stenoses of the Carotid Trunk

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    Three-dimensional ultrasonography is a significant novelty in neurosonology as it offers the possibility of an even more successful evaluation of atherosclerotic stenoses of the carotid trunk than previous ultrasonographic investigations. In 37 patients with signs of transitory ischemic attack and in 5 patients with reversible ischemic neurologic deficit we compared the findings of three-dimensional ultrasonography of carotid arteries on the neck with those of three-dimensional CT angiography. In 20 of these patients in which carotid thrombendarterectomy had been carried out, the findings of both diagnostic methods were also compared with the angiographic and operative findings. In 2 out of the total of 42 compared findings of three-dimensional ultrasonography, three-dimensional CT angiography and angiography of the carotid trunk, we assessed a difference in the evaluation of the degree of carotid stenosis while all other findings were in accordance as regards the evaluation of the degree of stenosis and plaque analysis. Of 20 operative findings, one showed insignificant deviations from the findings of both diagnostic methods. It is our opinion that three-dimensional ultrasonography is a reliable diagnostic method in evaluating atherosclerotic stenoses of carotid arteries. Every subtotal stenosis or internal carotid artery occlusion established by three-dimensional ultrasonography must be compared with three-dimensional CT angiography or classic angiography due to the objective possibility of false ultrasonographic interpretation and the significance of carotid thrombendarterectomy

    Функціональний стан м’язів зубощелепного апарату до та після лікування дітей з аномаліями прикусу та мовленнєвими порушеннями

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    During the examination of orthodontic patients, children with speech disorders were found. The myodynamic balance of antagonistic muscles and synergistic muscles is the relative stability of masticatory and mimic muscles, which for a long time persists without noticeable oscillations, contributes to the relatively stable state of dentoalveolar apparatus. The aim of the study – to determine the functional status of muscles of the dentoalveolar apparatus before and after treatment of children with anomalies of bite and speech disorders. Materials and Methods. To achieve study objectives for treatment we selected 44 patients with severe orthodontic pathology and speech disorders, with normal hearing and intellect. The method of a total (surface) electromyography was used to determine and analyze the indices of bioelectric activity of the muscles. Results and Discussion. There was normalization of parameters of bioelectric activity, decrease of parafunctional manifestations in muscles and decrease of the frequency of outbreaks of spontaneous activity of muscles at rest; normalization of the average amplitude of biopotentials in the state of activity, absence of fragmentation, improvement of synchronization and coordination of contractions of examined muscles in all pathologies of dental occlusion after the treatment. Conclusions. The orthodontic treatment performed provided the restoration of the neuromuscular balance of the dentoalveolar apparatus of patients with various dental occlusion pathologies, which has a beneficial effect on the correction of speech disorders.При обследовании ортодонтических пациентов были дети с речевыми нарушениями. Миодинамическое равновесие мышц-антагонистов и синергистов – это относительная устойчивость жевательных и мимических мышц, которая в течении длительного времени сохраняется без заметных изменений, способствует относительной стабильности зубочелюстного аппарата. Цель исследования – определить функциональное состояние мышц зубочелюстного аппарата до и после лечения детей с аномалиями прикуса и речевыми нарушениями. Материалы и методы. Для достижения поставленной цели было принято на лечение 44 пациента с выраженной ортодонтической патологией и речевыми нарушениями с нормальным слухом и интеллектом. Для определения и анализа показателей биоэлектрической активности мышц использован метод суммарной (поверхностной) электромиографии. Результаты исследований и их обсуждение. После проведённого лечения наблюдали нормализацию показателей биоэлектрической активности, уменьшение парафункциональних проявлений в мышцах и частоты вспышек спонтанной активности мышц в состоянии покоя, нормализация средней амплитуды биопотенциалов в состоянии активности, отсутствие фрагментаций, улучшение синхронности и координации сокращений обследованных мышц при всех патологиях прикуса. Выводы. Проведённое ортодонтическое лечение обеспечило восстановление нейромышечного баланса зубочелюстного аппарата пациентов с различными патологиями прикуса, что имеет благоприятное воздействие на коррекцию речевых нарушений.Під час обстеження ортодонтичних пацієнтів були діти з мовленнєвими порушеннями. Міодинамічна рівновага м’язів-антагоністів та синергістів – це відносна стійкість жувальних та мімічних м’язів, що протягом тривалого часу зберігається без помітних коливань, сприяє відносно стабільного стану зубощелепного апарату. Мета дослідження – визначити функціональний стан м’язів зубощелепного апарату до та після лікування дітей з аномаліями прикусу та мовленнєвими порушеннями. Матеріали і методи. Для досягнення поставленої мети було прийнято на лікування 44 пацієнти з вираженою ортодонтичною патологією та мовленнєвими порушеннями із нормальним слухом та інтелектом. Для визначення та аналізу показників біоелектричної активності м’язів використано метод сумарної (поверхневої) електроміографії. Результати досліджень та їх обговорення. Після проведеного лікування спостерігали нормалізацію показників біоелектричної активності, зменшення парафункціональних проявів у м’язах та частоти спалахів спонтанної активності м’язів у стані спокою, нормалізація середньої амплітуди біопотенціалів у стані активності, відсутність фрагментацій, покращення синхронності та координації скорочень обстежених м’язів при усіх патологіях прикусу. Висновки. Проведене ортодонтичне лікування забезпечило відновлення нейром’язового балансу зубощелепного апарату пацієнтів із різними патологіями прикусу, що має сприятливий вплив на корекцію мовленнєвих порушень

    The origin of paramagnetic magnetization in field-cooled YBa2Cu3O7 films

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    Temperature dependences of the magnetic moment have been measured in YBa_2Cu_3O_{7-\delta} thin films over a wide magnetic field range (5 <= H <= 10^4 Oe). In these films a paramagnetic signal known as the paramagnetic Meissner effect has been observed. The experimental data in the films, which have strong pinning and high critical current densities (J_c ~ 2 \times 10^6 A/cm^2 at 77 K), are quantitatively shown to be highly consistent with the theoretical model proposed by Koshelev and Larkin [Phys. Rev. B 52, 13559 (1995)]. This finding indicates that the origin of the paramagnetic effect is ultimately associated with nucleation and inhomogeneous spatial redistribution of magnetic vortices in a sample which is cooled down in a magnetic field. It is also shown that the distribution of vortices is extremely sensitive to the interplay of film properties and the real experimental conditions of the measurements.Comment: RevTex, 8 figure

    ALGORITHM FOR SPEECH DISORDERS CORRECTION USING PROPRIETARY CONSTRUCTION DEVICE

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    Currently, there is a tendency in Ukraine to increase the number of children with speech disorders. One of the most common disorders of speech function is dyslalia. Speech therapists are the main form of correctional training, children are assigned certain and consistent stages of speech therapy. Along with that, various individual and standard devices are used. The aim of the study – to conduct logopedic correction of speech disorders in patients with physiologic occlusion using the in-house designed device according to the proposed algorithm. Materials and Methods. A survey was conducted on 73 children (24 – aged 3 to 6 years, 49 – from 6 to 12 years old) without significant orthodontic pathology in the presence of speech impairment with normal hearing and intelligence and speech correction. In addition to logopedic exercises, it was recommended to use vestibular plates Dr. Hinz - MUPPY-P with beads, removable orthodontic devices with beads, Bluegrass appliances, devices for elimination and prevention of unhealthy tongue habits. In order to identify early risk factors for major dental diseases, the hygienic state of the cavity of the mouth, the intensity of caries, the presence or absence of inflammatory processes in the tissues of periodontal disease were determined. Results and Discussion. The first step in the algorithm for successful correction of speech disorders were to explain its necessity. The second stage involved the phonetic diagnosis of all aspects of speech, logic, intelligence, memory and thinking. Polymorphic dyslalia was diagnosed in all subjects of reporting panel. The third stage of the algorithm is to carry out work to overcome the abnormalities of the phonetic side of speech was a direct speech correction. The proposed device for elimination and prevention of unhealthy tongue habits was used in 6 cases. Conclusions. After the speech therapy correction correct articulation and sound were formed. The proposed device for the elimination and prevention unhealthy tongue habits should be used in conjunction with speech therapy, in particular, dyslalia. In addition to the positive logopedic effect of the proposed therapeutic and prophylactic measures, we have also received improvement of the hygienic state of the oral cavity, the absence of an increase in the intensity of the caries of permanent teeth and increased motivation in patients

    DETERMINATION OF OPTIMIZATION WAYS OF RE-PROTHESIS USING VARIOUS SCHEMES GNATHOLOGICAL SUPPORT OF PATIENTS AT THE PREPARATORY STAGE TO THE ORTHOPEDIC CORRECTION OF PATIENTS WITH OCCLUSIVE IATROGENIC DISORDERS OF TOOTH-JAW APPARATUS

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    We brought to the light that one of the the most controversial issues is the moment of adaptation to reconstructive procedures. Often it becomes unclear which and in which order to use medical diagnostic equipment, to training for fixed prosthetic stages. Our studies make it possible to predict not only the treatment time, but the amount of occlusal adjustment in conjunction with the reconstruction of the position of the mandible.One of the most debated issues is the time of adaptation to reconstructive manipulation. Often it becomes unclear how and in what order medical diagnostic equipment should be used in the preparatory stages of the stationary prosthetics. Our studies make it possible to predict not only the treatment time, and the amount of occlusal adjustment in conjunction with the reconstruction of the lower jaw. Keywords: tooth-jaw apparatus, temporomandibular joint, violation functional occlusion, dental surgery, medical diagnostic devices, muscle disorders, adaptation, occlusal splint, occlusal adjustment, chewing muscles, provisional design

    Genotypic and ecological variability of zinc content in the grain of spring bread wheat varieties in the international nursery KASIB

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    Spring bread wheat is the staple crop in Western Siberia and Kazakhstan, a significant portion of which goes for export. Wheat breeding with a high level of zinc in wheat grain is the most cost-effective and environmentally friendly way to address zinc de iciency in the diet. The purpose of this work was to evaluate the contribution of the factors ‘location’ and ‘genotype’ in the variability of zinc content in wheat grain, and to identify the best varieties as sources of this trait for breed-ing. The research on screening zinc content in the wheat grain of 49 spring bread wheat varieties from the Kazakhstan-Siberia Spring Wheat Trial (KASIB) nursery was carried out at 4 sites in Russia (Chelyabinsk, Omsk, Tyumen, Novosibirsk) and 2 sites in Kazakhstan (Karabalyk and Shortandy) in 2017–2018. The content of zinc in wheat grain was evaluated at the Ionomic Facility of University of Nottingham in the framework of the EU pro ject European Plant Phenotyping Network-2020. The analysis of variance showed that the main contribution into the general phenotypic variation of the studied trait, 38.7 %, was made by the factor ‘location’ due to different contents of zinc and moisture in the soil of trial sites; the effect of the factor ‘year’ was 13.5 %, and the effect of the factor ‘genotype’ was 8.0 %. The most favorable environmental conditions for accumulation of zinc in wheat grain were observed in the Omsk region. In Omsk, the average zinc content in all studied varieties was 50.4 mg/kg, with 63.7 mg/ kg in the best variety ‘OmGAU 100’. These values are higher than the target values of the international program Harvest Plus. ‘Novosibirskaya 16’ (49.4 mg/kg), ‘Silach’ (48.4 mg/kg), ‘Line 4-10-16’ (47.2 mg/ kg), ‘Element 22’ (46.3 mg/kg) and ‘Lutescens 248/01’ (46.0 mg/kg) were identi ied as being the best varieties. Significant possibilities for the production of wheat grain with high zinc content, which is in demand for the production of bread and pastry products with functional properties, were identified in the Western Siberian region

    Coordination between microbiota and root endodermis supports plant mineral nutrient homeostasis

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    Plant roots and animal guts have evolved specialized cell layers to control mineral nutrient homeostasis. These layers must tolerate the resident microbiota while keeping homeostatic integrity. Whether and how the root diffusion barriers in the endodermis, which are critical for the mineral nutrient balance of plants, coordinate with the microbiota is unknown. We demonstrate that genes controlling endodermal function in the model plant Arabidopsis thaliana contribute to the plant microbiome assembly. We characterized a regulatory mechanism of endodermal differentiation driven by the microbiota with profound effects on nutrient homeostasis. Furthermore, we demonstrate that this mechanism is linked to the microbiota's capacity to repress responses to the phytohormone abscisic acid in the root. Our findings establish the endodermis as a regulatory hub coordinating microbiota assembly and homeostatic mechanisms
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