Characterization of nanostructured spinel NiFe2O4 obtained by soft mechanochemical synthesis

Powdery nickel ferrite, NiFe2O4 has been obtained by soft mechanochemical synthesis in a planetary ball mill. Ni(OH)2 and Fe(OH)3 are used as initial compounds. This mixture was mechanically activated for 25h, uniaxial pressed and sintered at 1100°C for 2h. The phase composition of the sintered sample was analyzed by X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and Raman spectroscopy. Morphologies were examined by scanning electron microscopy (SEM). The electrical DC/resistivity/conductivity at different temperatures was measured using a Source Meter Keithley 2410. An Impedance/Gain-Phase Analyzer (HP-4194) was used to measure the impedance spectra (100Hz - 10MHz) at different temperatures. [Projekat Ministarstva nauke Republike Srbije, br. III 45003 i br. III 45015

Aortic stent-grafting: successful introduction into the combined procedure for coronary artery bypass grafting and aortic aneurysm repair

Objectives: Coronary artery bypass grafting (CABG) and combined stent-grafting (SG) were evaluated to reduce morbidity and mortality of patients with descending or infrarenal aortic aneurysm. Methods: CABG and SG (thoracic n=6, infrarenal n=36) were performed during the same hospitalization in 42 patients (mean age of 73±14 years). In 29 patients (mean Euroscore: 9), SG was performed under local anesthesia 9±3 days after coronary surgery (simultaneous) and in 13 patients (mean Euroscore: 7) during the same anesthesia (synchronous). In the latter group, 11 out of 13 patients underwent off-pump CABG. All aneurysms were treated by implantation of commercially available self-expanding grafts. Results: CABG was successful in all, but one patient with left internal mammary artery hypoperfusion syndrome, requiring an additional distal saphenous graft to the left anterior descending coronary artery. SG was uneventful in 98% (41/42 patients). Postoperative computerized tomography showed incomplete sealing in seven patients (17%), but only the two attachment endoleaks had to be treated by one proximal and one distal SG extension. Overall hospital stay for the synchronous repair was 12.5±6 days and that of the simultaneous group 17.5±7 days. Thirty-day mortality was 5% (2/42) as one patient of the simultaneous group experienced a lethal cerebral embolism during SG and one patient of the synchronous group developed an untreatable infection. In the follow-up of 4 years, there were two vascular reinterventions but no additional procedure-related morbidity or mortality. Conclusions: This experience shows that combined CABG and SG of thoracic or infrarenal aortic aneurysm is a safe and less-invasive alternative to the open graft repair, especially in the older patients or patients with severe comorbiditie

Intrinsic resistivity of sintered nickel manganite vs. powder activation time and density

Poster presented at the conference Fizika i tehnologija materijala (Physics and Technology of Materials), FITEM '07, Čačak, Serbia, August 6-8, 2007.Paper: [https://hdl.handle.net/21.15107/rcub_dais_208]Final results were published in the article [http://dx.doi.org/10.2298/SOS0801027S

Simple and Low-cost Fiber-optic Sensors for Detection of UV Radiation

In this paper two simple and low-cost fiberoptic sensors for detection of UV radiation are presented. A U-shaped sensor covered with an UV marker for UV radiation detection and a fiber-optic sensor with one end covered with powder from a mercury lamp are produced and described in details. Both sensors are made of large-core PMMA plastic optical fibers. As UV sources, a solar simulator and four different UV lamps are used. The light spectrum on the fiber output is measured by using an USB spectrometer. Dependence of output light intensity on the distance of end-type sensor with powder from a mercury lamp from UV lamp is investigated as well. On the output of the sensor covered with powder from a mercury lamp are obtained peaks of fluorescent emission at approximately 616 nm and 620 nm wavelengths

Influence of Bi2O3 on microstructure and electrical properties of ZnO-SnO2 ceramics

The effects of small amounts (0.5; 1.0 and 1.5 mol. %) of bismuth oxide on the microstructure and electrical properties of ZnO-SnO2 ceramics have been studied. Starting powders of ZnO and SnO2 were mixed in the molar ratio 2:1. After adding Bi2O3 this mixture was mechanically activated for 10 minutes in a planetary ball mill, uniaxially pressed and sintered at 1300ºC for 2h. The phase composition of the sintered samples was analyzed by X-Ray Diffraction (XRD) and by Energy Dispersive Spectrometer (EDS). Morphologies were examined by Scanning Electron Microscopy (SEM). An Impedance/Gain Phase Analyzer (HP 4194A) was used to measure the impedance spectra (100Hz - 10MHz) at different temperatures. The electrical DC resistivity/conductivity at different temperatures was measured using a High Resistance Meter (HP 4329A)

Biblioteke u domovima za stara i odrasla lica Ustanove Gerontološki centar Beograd

The research that has been conducted in four nursing homes of the Belgrade Gerontology Centre (BGC) in order to examine whether those homes have libraries, how they are structured and in what way they meet the demands of the beneficiaries - elderly people, having in mind that the access to libraries is a legally guaranteed right, being an ideal place to acquire knowledge and information, befriending, lifelong learning, and improving the overall quality of life in every possible way is presented here. BGC has four nursing homes such as: Nursing home Bezanijska kosa, Nursing home Vozdovac, Nursing home Karaburma and Nursing home Stacionar. By interviewing the employees in all four nursing homes along with the people in charge of the supply of current publications, we have gathered the necessary data that are published in this paper. The questionnaire about the workflow of the libraries consists of two parts: The questionnaire about the facilities - each for the aforementioned nursing home and the questionnaire about the library (accommodation, equipment, means of supply of the current inventory, the record of usage and procedure for borrowing publications, number of users, work time for each individual facility, etc.) It was essential for the research to form a questionnaire, carrying it out and summing up all gathered data into authentic conclusions regarding the subject in focus. The data are the indicator of current conditions, and also suggestions for improvements which were made while conducting the research, which is inspired by the scholarly literature and guidelines of the international library associations.У раду је представљено истраживање спроведено у четири дома за стара и одрасла лица Установе Геронтолошки центар Београд (УГЦБ),1 са циљем да се утврди да ли у њима постоје библиотеке, како су организоване и на који начин излазе у сусрет потребама корисника трећег животног доба, а полазећи од законом загарантованих права свих грађана на једнаку доступност библиотекама, као идеалног места за приступ знању и информацијама, дружење, целоживотно учење и унапређење квалитета живота. У оквиру УГЦБ послују четири дома за смештај одраслих и старих лица. То су Дом Бежанијска коса, Дом Вождовац, Дом Карабурма и Дом Стационар. Упитник о раду библиотека у оквиру УГЦБ састоји се из Упитника о установи и Упитника о библиотеци. Добијени подаци су показатељ тренутног стања, а у раду су дати и предлози за могућа унапређења, који су инспирисани стручном литературом и смерницама међународних библиотечких организација.U radu je predstavlјeno istraživanje sprovedeno u četiri doma za stara i odrasla lica Ustanove Gerontološki centar Beograd (UGCB),1 sa cilјem da se utvrdi da li u njima postoje biblioteke, kako su organizovane i na koji način izlaze u susret potrebama korisnika trećeg životnog doba, a polazeći od zakonom zagarantovanih prava svih građana na jednaku dostupnost bibliotekama, kao idealnog mesta za pristup znanju i informacijama, druženje, celoživotno učenje i unapređenje kvaliteta života. U okviru UGCB posluju četiri doma za smeštaj odraslih i starih lica. To su Dom Bežanijska kosa, Dom Voždovac, Dom Karaburma i Dom Stacionar. Upitnik o radu biblioteka u okviru UGCB sastoji se iz Upitnika o ustanovi i Upitnika o biblioteci. Dobijeni podaci su pokazatelј trenutnog stanja, a u radu su dati i predlozi za moguća unapređenja, koji su inspirisani stručnom literaturom i smernicama međunarodnih bibliotečkih organizacija

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700