79 research outputs found
Research of Microbiological Indicators of Quality of Surface Waters of Natural Environmental Territories of the Danube Basin
A comparative analysis of the sanitary and ecological state of surface watercourses in the upper part of the Danube basin (on theterritoryofUkraine) was carried out according to microbiological indicators. Similar hygienic studies were previously conducted in the middle and lower Danube inAustria,Slovakia,HungaryandRomania. InUkraine, the river network of theDanubeRiver basinwas not studied by microbiological indicators.The object of research is the watercourses on the territory of various zones of the nature protection object, which are different in function. This approach makes it possible to use hygienic indicators of water in protected areas of nature conservation areas as a reference for conducting background monitoring.The original design of the treatment plant based on the use of "Viya" fibrous carrier and "paste" technical structure is proposed. It was established that as the transition from the reserve to the economic zone occurs, the nitrate content in the water increases, the BOD increases in water, and the dissolved oxygen in the water decreases for all the watercourses studied. Significant differences in microbiological indices of watercourses of various functional zones of the protected object have been revealed.The possibility of using the sanitary-microbiological indicators of the river network as a reliable rapid test for assessing the state of environmental safety of nature conservation areas is shown
Spin Caloritronics
This is a brief overview of the state of the art of spin caloritronics, the
science and technology of controlling heat currents by the electron spin degree
of freedom (and vice versa).Comment: To be published in "Spin Current", edited by S. Maekawa, E. Saitoh,
S. Valenzuela and Y. Kimura, Oxford University Pres
Spectroellipsometric characterization and modeling of plasmonic diamond-like carbon nanocomposite films with embedded Ag nanoparticles
Frontal Bone Remodeling for Gender Reassignment of the Male Forehead: A Gender-Reassignment Surgery
Gender-reassignment therapy, especially for reshaping of the forehead, can be an effective treatment to improve self-esteem. Contouring of the cranial vault, especially of the forehead, still is a rarely performed surgical procedure for gender reassignment. In addition to surgical bone remodeling, several materials have been used for remodeling and refinement of the frontal bone. But due to shortcomings of autogenous bone material and the disadvantages of polyethylene or methylmethacrylate, hydroxyapatite cement (HAC) composed of tetracalcium phosphate and dicalcium phosphate seems to be an alternative. This study aimed to analyze the clinical outcome after frontal bone remodeling with HAC for gender male-to-female reassignment. The 21 patients in the study were treated for gender reassignment of the male frontal bone using HAC. The average age of these patients was 33.4 years (range, 21–42 years). The average volume of HAC used per patient was 3.83 g. The authors’ clinical series demonstrated a satisfactory result. The surgery was easy to perform, and HAC was easy to apply and shape to suit individual needs. Overall satisfaction was very high. Therefore, HAC is a welcome alternative to the traditional use of autogenous bone graft for correction of cranial vault irregularities
Preventive medicine of von Hippel-Lindau disease-associated pancreatic neuroendocrine tumors
Pancreatic neuroendocrine tumors (PanNETs) are rare in von Hippel-Lindau disease (VHL) but cause serious morbidity and mortality. Management guidelines for VHL-PanNETs continue to be based on limited evidence, and survival data to guide surgical management are lacking. We established the European-American-Asian-VHL-PanNET-Registry to assess data for risks for metastases, survival and long-term outcomes to provide best management recommendations. Of 2330 VHL patients, 273 had a total of 484 PanNETs. Median age at diagnosis of PanNET was 35 years (range 10-75). Fifty-five (20%) patients had metastatic PanNETs. Metastatic PanNETs were significantly larger (median size 5 vs 2\u2009cm; P\u20091.5\u2009cm in diameter were operated. Ten-year survival was significantly longer in operated vs non-operated patients, in particular for PanNETs <2.8\u2009cm vs 652.8\u2009cm (94% vs 85% by 10 years; P\u2009=\u20090.020; 80% vs 50% at 10 years; P\u2009=\u20090.030). This study demonstrates that patients with PanNET approaching the cut-off diameter of 2.8\u2009cm should be operated. Mutations in exon 3, especially of codons 161/167 are at enhanced risk for metastatic PanNETs. Survival is significantly longer in operated non-metastatic VHL-PanNETs
Вивчення резонансних дифракційних явищ на гратках точним методом зв’язаних хвиль з модифікованою системою рівнянь
В роботі представлені результати числового аналізу дифракції оптичних хвиль поперечної магнітної (ТМ) поляризації на гратках при наявності резонансу електромагнітного поля. Використано RCWA, в якому модифікована система рівнянь. Модифікація полягає в тому, що у системі диференціальних рівнянь змінені матриці Теплиця, які формуються на основі комплексних рядів Фур’є періодичної функції діелектричної проникності гратки та оберненої їй функції. Прямокутна функція зміни діелектричної проникності на періоді замінена на функцію трапеції, проте рельєф гратки лишається прямокутним. Така заміна функції діелектричної проникності точніше відповідає реальним граткам. Виявлено зменшення осциляцій коефіцієнтів відбивання та пропускання в залежності від кількості використаних зв’язаних хвиль та кращу збіжність результатів розрахунку для видозміненої системи рівнянь, особливо для металевих граток на діелектричних підкладках, в яких може спостерігатися резонанс локалізованих плазмонів, або резонанс електромагнітного поля в щілині гратки. Показано, що для діелектричних граток, розташованих на металевій підкладці, немає ні покращення ні погіршення збіжності при використанні модифікованої системи рівнянь в порівнянні з традиційним розкладом діелектричної проникності в ряд Фур’є. Для структури металева гратка на металевій підкладці досліджувався резонанс поверхневих плазмон-поляритонів, при виникненні якого коефіцієнт відбивання від гратки рівний нулю. Тут виникає особливо складна залежність коефіцієнта відбивання від кількості використаних зв’язаних хвиль при аналізі для обох модифікацій систем рівнянь. Спостерігаються сильні осциляції коефіцієнта відбивання від гратки при певних значеннях зв’язаних хвиль, які з їх ростом зменшуються.Results of a numerical analysis of the diffraction of optical waves of transverse magnetic (TM) polarization on gratings under the electromagnetic field resonance conditions are presented. Rigorous coupled wave analysis (RCWA) with modified equation system has been used. Modification is in change of the Toeplitz matrices in differential equation systems. These matrices are formed by complex Fourier series of a periodic function of the dielectric permittivity and its inversed function. Rectangular function of the dielectric permittivity per one period is changed by trapezoidal function; however, grating relief remains rectangular. Such replacement of the dielectric permittivity function more precisely corresponds to actual gratings. Oscillations of the reflectance and transmittance depending on the number of used coupled waves were reduced using modified equation system. Moreover, there is better convergence, especially in case of metallic gratings on the dielectric substrates, in which the localized plasmon resonance or the electromagnetic field resonance can occur in the grating slit. Any changes of the convergence with the use of modified systems of equations are not present in the case of dielectric gratings on the metallic substrates in comparison to the traditional expansion of the dielectric constant into a Fourier series. Surface plasmon-polariton resonance of a metal grating on metal substrate in case of which the reflectance from the grating is equal to zero was researched. There is a particularly complicated dependence of the reflectance on the number of coupled waves used in the analysis for both modifications of the equation system. Strong oscillations of the reflection coefficient from the grating are observed at certain values of coupled waves, which decrease with their growth
Метод ідентифікації користувача за клавіатурним почерком на основі нейромереж
With the development of advanced technologies, the problem of information security is becoming increasingly relevant. Given the development of spyware and digital technology allow more effective attacks on computer systems, including corporate networks, confidentiality can only be achieved through the creation of comprehensive information security. And one of the main elements of such a security system is the subsystem, which provides the identification of the user of the computer. Traditional identification and authentication methods based on the use of cards, electronic keys or other portable identifiers, as well as passwords and access codes, have significant disadvantages. The main disadvantage of such methods is the ambiguity of the identified person. Existing methods of user identification by keyboard handwriting are accurate from 78 % to 93,59 % and built on multilevel neural networks, which affects the speed of their learning and as a result of the cost of more resources, so it is actual to increase the accuracy of identification and reduce the time to train the neural network and design the appropriate method. An experimental study was made of the possibility of using a two-level neural network with a built-in sigmoid activation function to improve the accuracy of user identification by keyboard handwriting and proposed a method based on this mathematical apparatus. A comparison of the proposed identification method with existing ones was also performed, which showed an increase in the accuracy of user identification by 1–15 %. The method of Saket Maheshwari and Vikram Pudi has similar accuracy indicators, but there are several significant differences between the proposed and the existing method: in their work Saket Maheshwari and Wikam Pudi used a five-level neural network; it took 9 minutes to study their neural network. In the proposed method, the time of training the neural network is 6 minutes, which is faster for 3 minutes and, as a result, is much more effective when used, since the user's identification time is reduced and high identification accuracy is on the same high level.Проведено экспериментальное исследование возможности использования двухуровневой нейросети с встроенной сигмоидной активационной функцией для улучшения точности идентификации пользователя по клавиатурному почерку и предложен метод на основе данного математического аппарата, а также проведено сравнение предложенного метода идентификации с существующими. Полученные результаты показали, что предложенный метод имеет лучшую точность идентификации на 1–15 %.Проведено експериментальне дослідження можливості використання дворівненої нейромережі з вбудованою сигмоїдною активаційною функцією для покращення точності ідентифікації користувача за клавіатурним почерком, а також проведено порівняння запропонованого методу ідентифікації з існуючими. Отримані результати показали, що запропонований метод має кращу точність ідентифікаціїна 1-15 %
- …