The influence of porosity on the elasticity and strength of alumina and zirconia ceramics

This work investigates the behavior of porous alumina (with the porosity ranging from 18% to 70%) and zirconia (with the porosity ranging from 10% to 60%) ceramics when subjected to deformation by compression and shearing. The analysis of stress-strain curves showed that there is a transition from a typical brittle state for relatively dense ceramics, to a pseudo-plastic one for ceramics with high porosity. The values of the effective Young’s modulus, effective shear modulus and Poisson’s ratio decrease with the increase of the pore space volume of ceramics, which correlates with the appearance of multiple cracking during the deformation of the high porosity ceramics

Structures Formation on the Y-TZP-AI[2]O[3] Ceramic Composites Surface

The paper discusses the structure of Y-TZP-Al[2]O[3] ceramics produced from nanopowders and friction surface, wear resistance, friction coefficient of Y-TZP-AEO[3] composites rubbed against a steel disk counterface at a pressure of 5 MPa in a range of sliding speeds from 0.2 to 47 m/s. Analysis by X-ray diffraction, scanning electron microscopy showed that the high wear resistance of Y-TZP-Al[2]O[3] composites at high sliding speeds is due to high-temperature phase transitions and protective film formation on the friction surface

X-Ray Diffraction Analysis of the Sintered Y-TZP-AI[2]O[3] Ceramics

The paper discusses the wear resistance, friction coefficient, and structure of friction surfaces of fine-grained (0.2 [mu]m) Y-TZP-Al[2]O[3] composite rubbed against a steel disk counterface at a pressure of 5 MPa in a range of sliding speeds from 1 to 20 m/sec. It is shown that, starting at 2 m/sec, the fricti on surface is subdivided by a crack network into separate regions within which local spalling occurs at the maximum wear rate and a sliding speed of 5 m/sec. X-ray diffraction reveals inversion (with respect to the initial state) of the peak intensities of the tetragonal phase with random crystalline grain orientation. The degree of this inversion increases with sliding speed. These results are discussed in terms of the effects exerted by the reorientation of martensite-free deformation twins in the tetragonal phase and the formation of a quasi-liquid film on the wear resistance of fine-grained Y-TZP-Al[2]O[3]

Stage IV advanced endometrial cancer - case study

Scopul lucrării. Caz clinic ce confirmă că cancerul endometrial este o maladie potențial-operabilă în orice stadiu clinic. Materiale și metode. Pacienta 71 ani, diagnosticată clinic, paraclinic și prin stadializare chirurgicală. Histologia preoperator - adenocarcinom endometrial moderat-diferențiat G2. ECOG 0-1. Indicele masei corporale > 30. Pacienta a fost operată în cadrul Spitalului Internațional MedPark, Chișinău, Moldova: Histerectomie totală, anexectomie bilaterală, omentectomie supra- și infracolică, limfadenectomie pelvină și paraaortică, biopsie peritoneală. Tratament adjuvant: radioterapie externă/brahiterapie, 6 cure polichimioterapie carboplatin/taxane. Rezultate. Histologie postoperator - adenocarcinom mixt (endometrioid 60% și seros de grad înalt G3 40%), infiltrează tot miometrul la seroasă, trecere pe stroma cervixului, trompele uterine; afectează metastatic 24 din 55 ganglioni limfatici pelvini și paraaortali înlăturați; metastaze în oment și peritoneul parietocolic drept (M1). Încadrare TNM: pT3a (FIGO IVB), pN2a, LV1, Pn1, R0, M1. Concluzii. Supraviețuirea la 5 ani a cancerului endometrial în stadiile avansate este de 20%. Follow –up imagistic 34 luni – date de recidivare a patologiei nu se atestă. Deși tratamentul chimio/radioterapic este indicat în majoritatea cazurilor de cancer endometrial avansat, intervenția chirurgicală efectuată de o echipă multidisciplinară calificată într-un centru oncologic de specialitate este o opțiune dezirabilă de tratament, urmată de alte tratamente specifice.Aim of study. Case confirming that advanced endometrial cancer is a potentially operable disease in any stage. Materials and methods. 71 years old female with advanced endometrial cancer, clinically and surgically diagnosed. Preoperative histology - G2 moderately-differentiated endometrial adenocarcinoma. ECOG 0-1; body mass index > 30. Total hysterectomy with bilateral adnexectomy, omentectomy, pelvic and para-aortic lymphadenectomy, peritoneal biopsy performed in MedPark International Hospital, Chisinau, Moldova. Adjuvant treatment: external radiotherapy (DS 46Gy) and brachytherapy (DS 15Gy), 6 courses of carboplatin taxane polychemotherapy. Results. According to the postoperative histological result, a mixed adenocarcinoma was identified (endometrioid 60% and high-grade serous G3 40%) infiltrating the entire myometrium up to the serous and crossing the stroma of the cervix, fallopian tubes; metastatic 24 of 55 removed pelvic and para-aortic lymph nodes; metastases in omentum, right parietocolic peritoneum (M1). TNM classification: pT3a (FIGO IVB), pN2a, LV1, Pn1, R0, M1. Conclusions. The 5-year survival of patients with endometrial cancer in advanced stages is 72% in localized and 20% in metastasis, respectively. Imagistic Follow-up at 34 months – no recurrence of the pathology. Although chemotherapy/radiotherapy is indicated in most cases of advanced endometrial cancer, surgery performed by a qualified multidisciplinary team in a specialist oncology center is a desirable treatment option, followed by other specific treatments

Formation of Strategic Maps within the Framework of Realisation of the Process of Administration of Financial Security of a Company Формирование стратегических карт в рамках реализации процесса управления финансовой безопасностью предприятия

The article analyses approaches to the essence of administration of financial security of a company. It justifies expediency of introduction of a system approach to the system of administration of financial security of a company, the original idea of which is a necessity to determine influence of destabilising factors of internal and external environments when identifying the strategic goal of company’s activity. It specifies that one of the modern approaches of effective adaptation to the changing external environment, prevention and elimination of undesirable risks and threats, achievement of financial interests and long-term success of the subjects of economy in the process of ensuring their financial security is strategic administration. Methodological concept of strategic administration is a methodology of development of strategic maps of company development. It offers an algorithm of construction of a strategic map of administration of financial security of a company that provide establishment of target indicators of the level of financial security of a company and formation of effective managerial decisions in the process of their achievement.В статье проанализированы подходы к сущности управления финансовой безопасностью предприятия. Обоснована целесообразность внедрения системного подхода в систему управления финансовой безопасностью предприятия, исходной идеей которого является необходимость определения влияния дестабилизирующих факторов внутренней и внешней среды при определении стратегической цели деятельности предприятия. Указано, что одним из современных подходов эффективной адаптации к изменяющейся внешней среде, предупреждению и нейтрализации нежелательных рисков и угроз, достижению финансовых интересов и долгосрочного успеха субъектов хозяйствования в процессе обеспечения их финансовой безопасности является стратегическое управление. Методологической концепцией стратегического управления является методология разработки «стратегических карт» развития предприятия. Предложен алгоритм построения стратегической карты управления финансовой безопасностью предприятия, обеспечивающей установление целевых показателей уровня финансовой безопасности предприятия и формирование эффективных управленческих решений при их достижении

Approaches to preventive periodontal care for geriatric patients with somatic disorders

During the last two decades the acute interest in longevity has been kept by the world’s scientific community in relation to quality of health of older adults and prevention of emerging diseases including oral disorders in the old age. This article presents the study of oral conditions in 100 patients between the ages of 60 and 69 who were divided into three groups. This study aims to define approaches to preventive periodontal care for elderly patients with comorbidities. The primary group included patients with periodontal disease (PD) and salivary gland dysfunction: Sjogren’s disease and syndrome, non-insulin dependent diabetes mellitus, chronic pancreatitis. Two experimental groups included patients with normal salivary gland function and PD as well practically healthy persons without PD and normal salivary gland function. A comparative analysis of the results showed spread of dental caries (100%) and periodontal diseases (80%). The clear correlation between periodontium complex inflammation and poor oral hygiene is defined, mostly with men (p<0.05). Structural and optical properties of mixed saliva significantly change subject to periodontium inflammation and xerostomia: severity of xerostomia corresponding to profound hemodynamic and microcirculatory changes causes more intensive structural developmental abnormalities of mixed saliva. The important component of the Periodontal Treatment Protocol is to help older people develop skills and controls of effective thorough tooth brushing

Deformation and fracture mechanics of WC-(Fe-Mn-C) composite in axial compression

The paper analyzes the surface relief of a tungsten carbide-ferromanganese steel composite (WC-(Fe-Mn-C)) under axial compression, including its structure on the microscale (variation in coherent scattering region sizes and mode II stresses) and on the macroscale (accumulation of deformed WC grains and interface cracks, evolution of ordered shear bands). The analysis shows that compressing the composite decreases the average size of plastically deformed WC grains, increases the density of interface microcracks, and decreases the average shear band spacing. The composite reveals a stage character of deformation and prefracture correlating with its stress-strain curve. In the first strain hardening stage, the material is deformed in its matrix and WC grains without continuity loss. In the second stage, numerous shear macrobands oriented in two directions at similar to 45 degrees to the loading axis appear on its free surfaces. The macrobands are rich in deformed grains and cracks. Their intersection gives rise to macrocracks of length 40-150 mu m as precursors of catastrophic failure. Also presented are X-ray diffraction data on the fine crystal structure of the carbide and binder phases of WC-(Fe-Mn-C) at different loading stages. The data suggests that increasing the strain decreases the size of coherent scattering regions and increases the lattice microstress in both phases. The binder starts to deform earlier than the tungsten carbide. Most of the change in the fine crystal structure of the tungsten carbide falls on the stage of shear band formation