Laser operation of a Tm:Y₂O₃ planar waveguide

We demonstrate the first Tm-doped yttria planar waveguide laser to our knowledge, grown by pulsed laser deposition. A maximum output power of 35 mW at 1.95 µm with 9% slope efficiency was achieved from a 12 µm-thick film grown on a Y3Al5O12 substrate

Bacterial Contamination of Clothes and Environmental Items in a Third-Level Hospital in Colombia

Objective. This study evaluates the bacterial contamination rate of items in the hospital setting that are in frequent contact with patients and/or physicians. By determining the bacterial species and the associated antibiotic resistance that patients are exposed to. Methods. Hospital-based cross-sectional surveillance study of potential bacterial reservoirs. Cultures from 30 computer keyboards, 32 curtains, 40 cell phones, 35 white coats, and 22 ties were obtained. Setting. The study was conducted an urban academic 650-bed teaching hospital providing tertiary care to the city of Medellin, Colombia. Results. In total, 235 bacterial isolates were obtained from 159 surfaces sampled. 98.7% of the surfaces grew positive bacterial cultures with some interesting resistance profiles. Conclusion. There are significant opportunities to reduce patient exposure to frequently pathogenic bacteria in the hospital setting; patients are likely exposed to many bacteria through direct contact with white coats, curtains, and ties. They may be exposed to additional bacterial reservoirs indirectly through the hands of clinicians, using computer keyboards and cell phones

Planar waveguide lasers and spectroscopic study of upconversion solid-state materials

The increasing demand for high power laser sources with excellent beam quality operating in the visible and near-infrared electromagnetic radiation spectrum has prompted significant research effort into developing robust, reliable and efficient diode-pumped solid-state lasers (DPSSLs).The scope of this thesis is to study the planar waveguide laser (PWL) architecture, with semiconductor diode lasers (SDLs) pumping, along with the spectroscopic investigation of promising materials with embedded trivalent rare earth (RE) ions that may enable upconversion (UC) lasers of the future. The PWL architecture has distinct advantages over their bulk counterparts in terms of exceptional thermal management, compatibility with SDLs, typically high figures of merit regarding the intensity-interaction length product, leading to the possibility of enabling weak optical transitions.Several experiments are detailed in this thesis in order to point out unique properties of PWLs. The first, a demonstration of a Tm:Y2O3 PWL with a maximum output power of 35mW at 1.95 µm and slope efficiency of 9 %, with respect to the incident pump power. A 12 µm thick active film was grown by the pulsed laser deposition (PLD)technique on top of undoped Y3Al5O12 (YAG) crystal. That was the first demonstration at its kind,i.e. in terms of a sesquioxides PWL, one operating with Tm3+ as the optically active ion and in the 2 micron wavelength regime. Despite waveguide propagation losses on the order of 2 dB/cm, the efficiency was respectable, demonstrating the potential of these PLD films.The second PWL experiment was conducted with a state of the art double-clad Nd:YAG structure fabricated by Adhesive-Free Bonding technique, operating on a weak optical transition of this material, this is, at a wavelength of 1.83 µm, with an output laser power in excess of 1W in a near diffraction-limited optical beam. The main goal of this thesis, however, is to investigate the suitability of several different solid-state gain materials for generation of laser radiation in UV and purple-blue optical spectrum by means of the upconversion process via a sequential step pumping scheme. Nd- and Tm-doped crystals have been investigated for their spectroscopic properties associated with the pump absorption bands, emission strengths, and lifetimes of the main intermediate energy level of Tm3+, which would be likely a reservoir for the first excitation step. These comprehensive spectroscopic studies have been carried out in order to develop rate equations and gain analysis for prospective UC lasers from different host media. The prior literature results of upconversion lasers have been gathered for comparison with herein data and some general guidelines have been pointed out towards the future work.High resolution, absolute excited-state absorption (ESA) spectra, at room temperature,for the long-lived thulium and neodymium metastable levels (the 3F4 and 4F3/2 manifolds, respectively) were measured using a bespoke purpose built spectrophotometer based upon diodes and a dual lock-in amplifier technique. The aim of that investigation was to determine the strength of ESA channels at wavelengths addressable by commercially available SDLs operating around 630-680 nm and 440-470 nm wavelength. From those measurements, for Tm3+, the effective stimulated emission cross-sections were derived and used in the modelling of the potential gain for the UC transitions (wavelength below 500 nm) in a variety of hosts, including Y3Al5O12, YAlO3, LiYF4 and KY(WO4)2.Waveguides ordered for this project were not delivered. Notwithstanding, preparation of SDL pump sources for the double-excitation method, and the necessary optical components, was undertaken.With the gain studies, and initial hardware preparations, the ground has been laid that will enable the demonstration of new class of UV or purple-blue UC laser architecture in the near future.<br/

The level of knowledge of paramedics from Podkarpacie Province about the use of simulation in training

Szela Stanisław, Surowiec Tomasz, Ozga Dorota, Kiszka Jerzy, Jędrzejczyk‑Cwanek Marzena. The level of knowledge of paramedics from Podkarpacie Province about the use of simulation in training. Journal of Education, Health and Sport. 2017;7(11):93-102. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.1042922 http://ojs.ukw.edu.pl/index.php/johs/article/view/5009 https://pbn.nauka.gov.pl/sedno-webapp/works/836434 The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 1223 (26.01.2017). 1223 Journal of Education, Health and Sport eISSN 2391-8306 7 © The Authors 2017; This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. The authors declare that there is no conflict of interests regarding the publication of this paper. Received: 20.10.2017. Revised: 21.10.2017. Accepted: 07.11.2017. The level of knowledge of paramedics from Podkarpacie Province about the use of simulation in training Stanisław Szela1, Tomasz Surowiec2, Dorota Ozga1, Jerzy Kiszka1, Marzena Jędrzejczyk‑Cwanek1 1. Department of Didactics in Intensive Care and Emergency Medicine, Faculty of Medicine, University of Rzeszow 2. Emergency Medicine Student Scientific Circle, Department of Emergency Medicine, Faculty of Medicine, University of Rzeszow Abstract Introduction: Medical Simulation allows to improve knowledge, skills and social competences in undergraduate and post-graduate training in medical professions in a shorter time than traditional education. The aim of the paper was to assess the level of knowledge of paramedics on the use of medical simulation during undergraduate education in the field of emergency medicine. Material and Method The study was conducted from January to June 2014 among 60 paramedics from the Podkarpackie Province aged over 21. The research tool was the questionnaire developed by the authors. Results Men dominated in the study (18% women and 82% men). The most numerous group were the youngest subjects, i.e. between 21 and 30 (76%), and the smallest group was the oldest, i.e. over 40 (7%). The study demonstrated the relationship between respondents' responses regarding the use of patient simulators during university or postsecondary training and their self-assessment in terms of improved practical skills and their positive effect on the communication of paramedics with patients. Self-assessments of paramedics in terms of the increase of their practical skills through medical simulators correlated with the suitability of these skills in daily work and the impact on communication of medical rescue teams. Conclusions The medical simulation is used in the education of the students of medicine, but it is also of great importance in terms of modern teaching in emergency medicine, nursing, obstetrics in under and postgraduate education. Keywords: medical simulation, level of knowledge, paramedics, medical simulation, teaching paramedic

Surface Ultrastructure of Human Megakaryocytes Sorted on the Basis of DNA Content

The relationship of polyploidization (DNA content) to differentiation is not well defined. We have developed centrifugal elutriation and Percoll density gradient centrifugation to obtain larye numbers of highly-purified mega-karyocytes which subsequently were stained for DNA content with Hoechst 33342 and sorted by FACS into SC, 16C and 32C ploidy classes for correlated analysis of cell surface structures by scanning electron microscopy. Each ploidy class revealed unique surface characteristics that reflect differentiation occurring in megakaryocytes independent of their DNA content

Pompe disease - What do we currently know about the disease?

Introduction: Pompe disease (PD) is a rare metabolic disorder caused by a partial or complete deficiency of acid α-glucosidase (GAA) which leads to lysosomal accumulation of glycogen. Excessive amounts of glycogen accumulate mainly in the cells of the heart and skeletal muscles and cause dysfunction of these tissues. It is inherited in an autosomal recessive manner. The most common diagnostic methods include genetic tests and the measurement of enzyme activity in leukocytes or fibroblasts. A screening test is also available that tests the enzyme activity in dried blood spot (DBS). The treatment of PD is mostly based on synthetic GAA enzyme supply to the patients. The therapy reduces glycogen storage and improves muscle function, decreases heart size and prolongs the lives of those with infantile form of PD. In the adult onset of the disease treatment increases physical efficiency and reduces the progression of respiratory failure. Aim of the study: Systematization of current knowledge about Pompe disease with particular emphasis on possible clinical presentations, diagnostics and therapeutic options. Material and methods: Literature review based on PubMed data using the following keywords: Pompe disease, Glycogenosis type ii, glucosidase alpha Summary : Pompe disease is a rare disease with many problems related to diagnosis and possible therapies. Its symptoms can be very misleading and cause a delay in diagnosis . It is critical to start the therapy as soon as possible to best manage the disease. The prognosis of PD is poor, especially in children under 12 months of age. Gene therapy research is currently underway and early results are very promising. There is still much to learn about dealing with this disease

Direct oral anticoagulants in the treatment of cerebral venous sinus thrombosis: a single institution’s experience

Aim of the study. Oral anticoagulants, preferentially vitamin K antagonists (VKA), are recommended for 3–12 months in patients with cerebral venous sinus thrombosis (CVST). We present a series of patients with CVST treated with direct oral anticoagulants (DOAC). Materials and methods. We prospectively recruited 36 patients with CVST (aged 40.3 ± 9.2 years, 58.3% female) treated with DOAC based on the physician’s or patient’s preferences. Functional outcome was assessed with modified Rankin Scale. Recanalisation was assessed on imaging at 3–6 months post the event. Patients were followed for a median of 30 [interquartile range (IQR) 25–37] months. Results. After use of heparin (median: 6 days; IQR 5–8.75), patients received dabigatran (150 mg bid, n = 16 or 110 mg bid, n = 2), rivaroxaban (20 mg qd, n = 10) or apixaban (5 mg bid, n = 8) for a median of 8.5 months (IQR 6.25–12). Complete or partial recanalisation was observed in 34 cases (94.4%). Three patients (8.3%) experienced major bleeding: menorrhagia on rivaroxaban (n = 2) and gastrointestinal bleeding on dabigatran (n = 1). A favourable functional outcome was observed in 24 (66.7%) patients, without any fatality. CSVT recurred in two patients (5.6%) and two venous thromboses developed in two other patients with inherited thrombophilia after anticoagulation withdrawal. Conclusions and clinical implications. DOACs could be an alternative to VKA in CVST patients