Numerical modeling of a table-top tunable Smith-Purcell Terahertz free-electron laser operating in the super-radiant regime

Terahertz (THz) radiation occupies a very large portion of the electromagnetic spectrum and has generated much recent interest due to its ability to penetrate deep into many organic materials without the damage associated with ionizing radiation such as x-rays. One path for generating copious amount of tunable narrow-band THz radiation is based on the Smith-Purcell free-electron laser (SPFEL) effect. In this Letter we propose a simple concept for a compact two-stage tunable SPFEL operating in the superradiant regime capable of radiating at the grating's fundamental bunching frequency. We demonstrate its capabilities and performances via computer simulation using the conformal finite-difference time-domain electromagnetic solver {\sc vorpal}.Comment: 4 pages, 5 figures, accepted for publication in Applied Physics Letter

Hemiprosthesis for Femoral Neck Fractures in the Elderly: A Retrospective Study of 319 Patients

Background: In geriatric patients with Pauwels types II and III femoral neck fractures, hemiprosthesis is the therapy of choice. Objectives: This study was conducted to analyze the results after cemented hemiprosthesis placement, the first year after surgery. Patients and Methods: This retrospective study was conducted on 319 patients over 70 years with displaced femoral neck fractures treated surgically at our hospital from 2007 to 2012. All medical information was available including retrospective posthospital discharge records as well as inpatient course and one-year mortality. Results: From a total of 319 patients, 78% (n = 249) were female and 22% (n = 70) were male, with the mean age of 83.6 years. Seventeen percent of the patients suffered from heart failure, 23% from diabetes, and 19% from renal insufficiency. Time to surgery averaged one day postinjury. Average operative time skin-to-skin was 50 minutes. Seventy-three percent of the patients could mobilize independently on discharge. Of the remaining patients, 2/3 had already lost independent mobilization prior to the fracture. Hospital mortality averaged 5% (national average in Germany: 8%), and 30-day and 90-day mortality rates were 5% and 15%, respectively. Within one year, 22% of the patients died (national average: 27%). Also, 14 patients were re-admitted, for contralateral prosthetic implantation (n = 7) or revision after the periprosthetic fracture (n = 5). Fifty-three percent of the patients were admitted to hospital during the year for other diseases (national average: 54%). Conclusions: Hemiprosthesis placement for displaced femoral neck fractures is a common and safe procedure. Despite recent decreases in hospital mortality, the risk of death remains more than twice as high within one year than that for uninjured patients of the same age

The transformation of the political system of Ukraine: balancing on the edge of democracy and authoritarianism

24 серпня 1991 року Україна, одна з колишніх радянських республік, стала незалежною. Це був її перший крок на шляху до демократії і можливість творення своєї власної політичної системи. Незалежність дала Україні багато можливостей: встановлювати напрями зовнішньої політики, доступ до міжнародних організацій. Метою даної роботи є аналіз трансформації української політичної системи в контексті балансування на грамі демократії і авторитаризму.On August 24th, 1991 Ukraine, one of the former Soviet republics, gained independendence. It was the first step towards democracy and possible creation of it's own political system. Independence gave Ukraine many opportunities to set the directions of foreign policy, to cooperate with chosen states and access to international ogranizations. The aim of this work was to analyze transformation of the Ukrainian political system in the context of balancing per gram of democracy and authoritarianism.Робота виконана на кафедрі Східної Європи Університету Миколи Коперника в Торун

Обрис проукраїнської державницької діяльності А. Шептицького

Prokop, N.M. (2015), “Essay of A. Sheptytskyi’s pro-Ukrainian state activity” [“Obraz proukrainskoi derzhavnytskoi diialnosti A. Sheptytskoho”], Pravo i Bezpeka, No. 3, pp. 35–41.Прокоп, Н. М. Обрис проукраїнської державницької діяльності А. Шептицького // Право і безпека. - 2015. - № 3 (58). - С. 35–41.Досліджено актуальні в сучасних умовах розвитку української держави погляди митрополита А. Шептицького та його суспільно-політичну та державну діяльність у період національно-визвольного руху на рубежі ХІХ–ХХ ст., становлення та занепаду УНР, затвердження більшовицької влади в Галичині. Акцентовано увагу на діяльності А. Шептицького, спрямованій на подолання розбіжностей в середовищі польського та українського національно-визвольних рухів, а також на єднання українського народу через об’єднання віруючих усіх християнських конфесій.Important for modern Ukrainian state building points of view of Metropolitan A. Sheptytskyi and his socio-political and state activities during the national liberation movement in the late ХІХ and early ХХ centuries, formation of the UPR, its disintegration and consolidation of Bolshevik power in Galicia are studied. Special attention is paid to his activities aimed at overcoming differences among Polish and Ukrainian national liberation movements, and the unity of Ukrainian nation by uniting believers of all Christian denominations. It is revealed that the active participation of Metropolitan A. Sheptytskyi in socio-political life, his state position has contributed to the specification and theoretical arrangement of Ukrainian national idea. Due to his intellectual prestige and hard work, he made tolerant attitude of European states to the aspirations of Ukrainian people to develop their national statehood; he also strengthened and developed Ukrainian state and national awareness and the will to fight for the independence of Ukrainian people against imperial states.Исследованы актуальные в современных условиях развития украинского государства взгляды митрополита А. Шептицкого и его общественно-политическая и государственная деятельность в период национально-освободительного движения на рубеже ХІХ–ХХ вв., становления и упадка УНР, утверждения большевистской власти в Галичине. Акцентировано внимание на деятельности А. Шептицкого, направленной на преодоление разногласий в среде польского и украинского национально-освободительных движений, а также на единение украинского народа через объединение верующих всех христианских конфессий

Cross-border cooperation in Poland and Ukraine (incidents regional cooperation: Warmian-Masurian Voivodeship and Rivne region)

Міжнародне міжрегіональне співробітництво є дуже важливим аспектом політики в галузі розвитку польських воєводств. Головним чином тому, що забезпечує обмін досвідом між регіонами з різних країн та підтримує ініціативи з поліпшення якості фукцйоновання регіоналних інституцій. Місцеве самоврадування Вармінсько-Мазурського воєводства надає велике значення відносини з Україною, Східним сусідом Польщі. Важливим аспектом для цієї співпраці є наявність великої і дуже активної групи української меншини в регіоні, тому у співпраця та це важливий аспект міжнародної політики воєводства.Polish relation with Ukrainie are developing in 1991. Authors aim is present short outline of issues of Polish and Ukrainian international law regulation about crossborder regional cooperation casusРоботу виконано на кафедрі Східної Європи Університету Миколи Коперника в Торун

Towards automatic pulmonary nodule management in lung cancer screening with deep learning

The introduction of lung cancer screening programs will produce an unprecedented amount of chest CT scans in the near future, which radiologists will have to read in order to decide on a patient follow-up strategy. According to the current guidelines, the workup of screen-detected nodules strongly relies on nodule size and nodule type. In this paper, we present a deep learning system based on multi-stream multi-scale convolutional networks, which automatically classifies all nodule types relevant for nodule workup. The system processes raw CT data containing a nodule without the need for any additional information such as nodule segmentation or nodule size and learns a representation of 3D data by analyzing an arbitrary number of 2D views of a given nodule. The deep learning system was trained with data from the Italian MILD screening trial and validated on an independent set of data from the Danish DLCST screening trial. We analyze the advantage of processing nodules at multiple scales with a multi-stream convolutional network architecture, and we show that the proposed deep learning system achieves performance at classifying nodule type that surpasses the one of classical machine learning approaches and is within the inter-observer variability among four experienced human observers.Comment: Published on Scientific Report

Patch Plate Materials Compatibility Assessment

Lunar dust proved to be a greater problem during the Apollo missions than was originally anticipated. The highly angular, charged dust particles stuck to seals, radiators, and visors; clogged mechanisms; and abraded space suits. As reported by Apollo 12 astronaut Pete Conrad "We must have had more than a hundred hours suited work with the same equipment, and the wear was not as bad on the training suits as it is on these flight suits in just the eight hours we were out.". Dust clinging to surfaces was also transport-ed into habitable spaces leading to lung and eye irritation of the astronauts. The Apollo astronauts were on the Lunar surface less than 24 hours and experienced many dust related problems. With the Artemis program, we are planning longer stays on the surface, with more activities that have the potential to put the astronauts and equipment in contact with greater quantities of Lunar dust. The success of these missions will depend on our understanding of material interactions with Lunar dust and the development of ways to mitigate dust effects in cases where exposure to dust will lead to failure of components, unacceptable loss of power or thermal control, unacceptable loss of visibility, or health issues. Through the Lunar Surface In-novation Initiative (LSII), we are initiating a Patch Plate Materials Compatibility Assessment project. The overall goal of the three year project is to develop passive approaches to mitigate Lunar dust adhesion to surfaces for technologies that are currently at TRL levels 2-3 to bring them to TRL level 5 through ground-based assessment, culminating in a demonstration flight experiment on a Commercial Lunar Payload Services (CLPS) lander in 2022-2023. This paper discusses the detailed technical objectives and approach for this project. References: Gaier, J.R. "The Effects of Lunar Dust on EVA Systems During the Apollo Missions," NASA/TM-2005-213610/REV1, (2005), Apollo 12 Technical Crew Debriefing, December 1, 1969, pp. 10-54