417 research outputs found
Splitting times of doubly quantized vortices in dilute Bose-Einstein condensates
Recently, the splitting of a topologically created doubly quantized vortex
into two singly quantized vortices was experimentally investigated in dilute
atomic cigar-shaped Bose-Einstein condensates [Y. Shin et al., Phys. Rev. Lett.
93, 160406 (2004)]. In particular, the dependency of the splitting time on the
peak particle density was studied. We present results of theoretical
simulations which closely mimic the experimental set-up. Contrary to previous
theoretical studies, claiming that thermal excitations are the essential
mechanism in initiating the splitting, we show that the combination of
gravitational sag and time dependency of the trapping potential alone suffices
to split the doubly quantized vortex in time scales which are in good agreement
with the experiments. We also study the dynamics of the resulting singly
quantized vortices which typically intertwine--especially, a peculiar vortex
chain structure appears for certain parameter values.Comment: 5 pages, 5 figure
Environmental responsibility in hospital care : findings from a qualitative study
Objective: To identify the key elements of environmental responsibility in hospital care and the stakeholders involved.
Background: Hospital care causes a significant global environmental burden, which threatens human health and wellbeing. Environmental responsibility has been identified as an essential part of patient care with regard to health promotion and wellbeing of humans, but it has often been regarded as a secondary issue in hospitals. In addition, the lack of organizational structures and administrative as well as managerial support inhibit the promotion of environmental responsibility in hospitals. Methods: We used a qualitative study with semi-structured interviews and document analysis. Our data was drawn from the environmental managers of five Finnish university hospitals and documents on their environmental programs. Results: We found that the aim of environmental responsibility in hospital care was to avoid unnecessary emissions, and that it was guided by the authorities and by ethical values. It included targets for sustainable use of material, electricity, water and
transport. Environmental responsibility required the involvement of several stakeholders, including administrators, environmental
manager, immediate leaders, environmental support people, staff and patients. Implementation of environmental responsibility was promoted by collaboration, education, diverse initiatives to motivate staff, and continuously developing practices. Conclusions: Environmental responsibility extended throughout a hospital organization. Staff was in a key position to implement it, but they needed versatile organizational support, including education, clear procedures, defined roles, and a motivational culture and facilities. Implications for hospital management: This study yields new knowledge that will provide information for the development of organisational structures with respect to environmental responsibility in hospital care.
Keywords: Environmental manager, Environmental program, Environmental responsibility, Hospital, Key informan
Non-Abelian magnetic monopole in a Bose-Einstein condensate
Recently, an effective non-Abelian magnetic field with a topology of a
monopole was shown to emerge from the adiabatic motion of multilevel atoms in
spatially varying laser fields [J. Ruseckas et al., Phys. Rev. Lett. 95, 010404
(2005)]. We study this monopole in a Bose-Einstein condensate (BEC) of
degenerate dressed states and find that the topological charge of the
pseudospin cancels the monopole charge resulting in a vanishing gauge invariant
charge. As a function of the laser wavelength, different stationary states are
classified in terms of their effect to the monopole part of the magnetic field
and a cross-over to vortex ground state is observed.Comment: 5 pages, 1 color figure; v2 modified according to referees'
suggestions, some typos corrected; v3 minor modifications, published versio
Ground-State Dirac Monopole
We show theoretically that a monopole defect, analogous to the Dirac magnetic
monopole, may exist as the ground state of a dilute spin-1 Bose-Einstein
condensate. The ground-state monopole is not attached to a single semi-infinite
Dirac string, but forms a point where the circulation of a single vortex line
is reversed. Furthermore, the three-dimensional dynamics of this monopole
defect are studied after the magnetic field pinning the monopole is removed and
the emergence of antimonopoles is observed. Our scheme is experimentally
realizable with the present-day state of the art
Internet as a source of medicines information (MI) among frequent internet users
Background: The internet is widely and increasingly used to search for health information. Previous studies have focused mainly on health information on the internet and not specifically on medicines information (MI). Objectives: The aim of this study was to explore the internet as a source of MI compared to other sources of MI; to identify those who use the internet as a source of MI; and to describe patterns of use of the internet as a source of MI. Methods: A cross-sectional design employed a web-based questionnaire posted by patients' and other organizations as well as pharmacies on their websites during six weeks in the beginning of 2014. Logistic regression analysis was used to assess associations of background variables to the use of different MI sources. Results: The most frequently used MI sources among respondents (n = 2489) were package leaflets (90%), pharmacists (83%), physicians (72%), and the internet (68%). According to a multivariate analysis, internet use for MI was associated with female gender, age <65 years, higher education, daily use of the internet, and continuous use of vitamins or herbals. MI was most commonly searched from a Finnish health portal (56%) and websites of pharmacies (41%). Of the respondents, nearly half (43%) used search engines to find information from the internet. The names of the medicinal product, symptom or disease were the most commonly used search terms. Conclusions: Well-educated, young women tend to search MI on the internet. Health care professionals should discuss reliable MI websites and tools that can help patients evaluate the reliability of information.Peer reviewe
Comparison of two rebound tonometers in healthy horses
Objective: To obtain a reference range for evaluation of intraocular pressure (IOP) in horses using Tonovet Plus (R), to compare the IOP readings obtained with Tonovet (R) and Tonovet Plus (R), and to evaluate the repeatability of readings. Animals studied and Procedures: Intraocular pressure of 30 client-owned horses (60 eyes) with no signs of illness or ocular disease was evaluated using Tonovet (R) and Tonovet Plus (R) rebound tonometers. Horses' mean age was 10.7 (range 6-17) years. Triplicate measurements were performed without using sedatives or local anesthetics, with minimal restraint. Results: Calculated reference intervals (the CLSI robust method) were 14.4-27.2 mmHg for Tonovet (R) and 16.0-26.1 mmHg for Tonovet Plus (R). Mean values (+/- standard deviation, SD [+/- coefficient of variation, CV]) obtained with Tonovet Plus (R)(21.6 +/- 2.45 mmHg [11.3%]) were on average 0.6 mmHg higher than with Tonovet (R)(21.0 +/- 3.14 mmHg [15.0%]), and a negligible statistical difference between the devices was found using the paired sample t test (P = .049). The correlation coefficient for the averaged triplicate measurements was 0.73. The average CV was 4.6% and 4.4% for Tonovet (R) and Tonovet Plus (R), respectively. Conclusions: The repeatability of measurements was very good with both devices. The readings between the two devices differed statistically significantly, but the correlation was considered good and the variation was numerically small, and thus, the difference was considered clinically irrelevant. When monitoring disease process or treatment response in an individual patient, repeated readings are best performed using a similar device to avoid false interpretation of results.Peer reviewe
Pleolipoviridae, a newly proposed family comprising archaeal pleomorphic viruses with single-stranded or double-stranded DNA genomes
Viruses infecting archaea show a variety of virion morphotypes, and they are currently classified into more than ten viral families or corresponding groups. A pleomorphic virus morphotype is very common among haloarchaeal viruses, and to date, several such viruses have been isolated. Here, we propose the classification of eight such viruses and formation of a new family, Pleolipoviridae (from the Greek pleo for more or many and lipos for lipid), containing three genera, Alpha-, Beta-, and Gammapleolipovirus. The proposal is currently under review by the International Committee on Taxonomy of Viruses (ICTV). The members of the proposed family Pleolipoviridae infect halophilic archaea and are nonlytic. They share structural and genomic features and differ from any other classified virus. The virion of pleolipoviruses is composed of a pleomorphic membrane vesicle enclosing the genome. All pleolipoviruses have two major structural protein species, internal membrane and spike proteins. Although the genomes of the pleolipoviruses are single- or double-stranded, linear or circular DNA molecules, they share the same genome organization and gene synteny and show significant similarity at the amino acid level. The canonical features common to all members of the proposed family Pleolipoviridae show that they are closely related and thus form a new viral family.Peer reviewe
Whom to blame for metastasis, the epithelial-mesenchymal transition or the tumor microenvironment?
Changes in the tumor microenvironment (TME) can trigger the activation of otherwise non-malignant cells to become highly aggressive and motile. This is evident during initial tumor growth when the poor vascularization in tumors generates hypoxic regions that trigger the latent embryonic program, epithelial-to-mesenchymal transition (EMT), in epithelial carcinoma cells (e-cars) leading to highly motile mesenchymal-like carcinoma cells (m-cars), which also acquire cancer stem cell properties. After that, specific bidirectional interactions take place between m-cars and the cellular components of TME at different stages of metastasis. These interactions include several vicious positive feedback loops in which m-cars trigger a phenotypic switch, causing normal stromal cells to become pro-tumorigenic, which then further promote the survival, motility, and proliferation of m-cars. Accordingly, there is not a single culprit accounting for metastasis. Instead both m-cars and the TME dynamically interact, evolve and promote metastasis. In this review, we discuss the current status of the known interactions between m-cars and the TME during different stages of metastasis and how these interactions promote the metastatic activity of highly malignant m-cars by promoting their invasive mesenchymal phenotype and CSC properties. (C) 2016 Elsevier Ireland Ltd. All rights reserved
Renal denervation in patients who do not respond to cardiac resynchronization therapy
Cardiac resynchronization therapy (CRT) reduces the morbidity and mortality in advanced heart failure (HF) in about two-thirds of the patients. Approximately one-third of the patients do not respond to CRT. The overactivity of sympathetic nervous system is associated with advanced HF and deteriorates the hemodynamic state. We tested the hypothesis that controlling sympathetic overactivity by renal denervation (RDN) could be beneficial in nonresponders for CRT. In our HeartF-RDN study (ClinalTrials.gov. NCT02638324), RDN could not reverse the progression of HF in subjects with New York Heart Association Classification (NYHA) III-IV stage symptoms.Peer reviewe
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