What Helps, What Hinders? Undergraduate Nursing Students' Perceptions of Clinical Placements Based on a Thematic Synthesis of Literature.

Introduction: Clinical placements are a mandatory component of nursing students' education internationally. Despite clinical education being a key to nursing students' achievement of nursing competencies, few studies have reviewed students' narratives to describe their experiences of learning during clinical placement. Such studies may be important in offering a deeper insight into clinical learning experiences than quantitative surveys. Methods: A systematic thematic synthesis of qualitative studies between 2010 and June 2020 was conducted. English language studies that offered a thematic analysis of undergraduate nursing students' experiences of learning during placement were sought. A search was made of five databases PubMed, Ovid Medline, CinahlPlus, SCOPUS, and Google Scholar. The study was guided by the ENTREQ statement for enhancing transparency in reporting the synthesis of qualitative research. Results: Twenty-seven qualitative studies were included in the review. A thematic synthesis showed over 100 themes and subthemes across the studies. A cluster analysis revealed positive elements and others that were seen in the studies as a barrier (hindrance) to clinical learning. Positive elements included supportive instructors, close supervision, and belonging (in the team). Unsupportive instructors, a lack of supervision and not being included were seen as a hindrance. Three key overarching themes that could describe a successful placement were revealed as "Preparation," "Welcomed and wanted" and "Supervision experiences". A conceptual model of clinical placement elements conducive to nursing students' learning was developed to enhance understanding of the complexities associated with supervision. The findings and model are presented and discussed. Conclusion: The conceptual model presents positive elements that influence students' clinical placement experiences of learning. This model may provide a framework to guide professional development programs and strategies to support students and supervisors alike, an important step forward in moving beyond the current clinical placement rhetoric

Room temperature magnetism in LaVO3/SrVO3 superlattices by geometrically confined doping

Based on the Hubbard model of strongly correlated systems, a reduction in the bandwidth of the electrons can yield a substantial change in the properties of the material. One method to modify the bandwidth is geometrically confined doping, i.e. the introduction of a (thin) dopant layer in a material. In this paper, the magnetic properties of LaVO$_3$/SrVO$_3$ superlattices, in which the geometrically confined doping is produced by a one monolayer thick SrVO$_3$ film, are presented. In contrast to the solid solution La$_{1-x}$Sr$_x$VO$_3$, such superlattices have a finite magnetization up to room temperature. Furthermore, the total magnetization of the superlattice depends on the thickness of the LaVO$_3$ layer, indicating an indirect coupling of the magnetization that emerges at adjacent dopant layers. Our results show that geometrically confined doping, like it can be achieved in superlattices, reveals a way to induce otherwise unaccessible phases, possibly even with a large temperature scale.Comment: 5 pages, 4 figure

T and CPT Symmetries in Entangled Neutral Meson Systems

Genuine tests of an asymmetry under T and/or CPT transformations imply the interchange between in-states and out-states. I explain a methodology to perform model-indepedent separate measurements of the three CP, T and CPT symmetry violations for transitions involving the decay of the neutral meson systems in B- and {\Phi}-factories. It makes use of the quantum-mechanical entanglement only, for which the individual state of each neutral meson is not defined before the decay of its orthogonal partner. The final proof of the independence of the three asymmetries is that no other theoretical ingredient is involved and that the event sample corresponding to each case is different from the other two. The experimental analysis for the measurements of these three asymmetries as function of the time interval {\Delta}t > 0 between the first and second decays is discussed, as well as the significance of the expected results. In particular, one may advance a first observation of true, direct, evidence of Time-Reserval-Violation in B-factories by many standard deviations from zero, without any reference to, and independent of, CP-Violation. In some quantum gravity framework the CPT-transformation is ill-defined, so there is a resulting loss of particle-antiparticle identity. This mechanism induces a breaking of the EPR correlation in the entanglement imposed by Bose statistics to the neutral meson system, the so-called {\omega}-effect. I present results and prospects for the {\omega}-parameter in the correlated neutral meson-antimeson states.Comment: Proc. DISCRETE 2010, Symposium on Prospects in the Physics of Discrete Symmetries, December 2010, Rom

Disposition and residues of marbofloxacin in eggs of laying hens

Marbofloxacin belongs to the group of fluoroquinolones, used exclusively in domestic animals. This study was carried out with the purpose of studying the temporal disposition of marbofloxacin in edible compartments of the egg after administration of 1, 52 mg/kg of marbofloxacin in drinking water for 11 consecutive days in hens in posture peak and average weight of 1,91±0,25 kg. Birds were housed in individual cages under controlled light conditions, ambient temperature, relative humidity, water and balanced feed ad libitum. After the administration, eggs were collected daily and immediately separated into albumen and yolk, identified per bird/day and stored at-20°C until analysis. The preparative assay consisted in extraction of the analyte using 200 mg of yolk or albumen, as appropriate, in deionized water, homogenizing solution and enrofloxacin solution as internal standard. Separation and quantification were performed by HPLC by reverse phase isocratic elution with fluorescence detector, mobile phase composed of water, acetonitrile and triethylamine adjusted to pH 3. According to the peak areas of known concentrations, the concentrations of the test samples were calculated by simple linear regression. The established marbofloxacin levels are higher and more persistent in the yolk than in albumen, reaching 8 and 9 days, respectively. The disposition characteristics observed with marbofloxacin are compatible with the physico-chemical properties of the antimicrobial with the respective compartments of the egg and the time required for its formation. Data obtained from marbofloxacin depletion in egg compartments were analyzed using the EMEA WT 1.4 software and conjecturing a rigorous MRL (0,001 µg/kg), a withdrawal period of 13 and 17 days was estimated, for albumen and yolk, respectively.Fil: Errecalde, Carlos. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Urzúa Pizarro, Natala Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto; ArgentinaFil: Prieto, G.. Universidad Nacional de Río Cuarto; ArgentinaFil: Luders, C.. Universidad Catolica de Temuco.; ChileFil: Liboa, Rosendo Anibal. Universidad Nacional de Río Cuarto; ArgentinaFil: Gramaglia, Romina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; Argentin

Cytosolic chaperones influence the fate of a toxin dislocated from the endoplasmic reticulum

The plant cytotoxin ricin enters target mammalian cells by receptor-mediated endocytosis and undergoes retrograde transport to the endoplasmic reticulum (ER). Here, its catalytic A chain (RTA) is reductively separated from the cell-binding B chain, and free RTA enters the cytosol where it inactivates ribosomes. Cytosolic entry requires unfolding of RTA and dislocation across the ER membrane such that it arrives in the cytosol in a vulnerable, nonnative conformation. Clearly, for such a dislocated toxin to become active, it must avoid degradation and fold to a catalytic conformation. Here, we show that, in vitro, Hsc70 prevents aggregation of heat-treated RTA, and that RTA catalytic activity is recovered after chaperone treatment. A combination of pharmacological inhibition and cochaperone expression reveals that, in vivo, cytosolic RTA is scrutinized sequentially by the Hsc70 and Hsp90 cytosolic chaperone machineries, and that its eventual fate is determined by the balance of activities of cochaperones that regulate Hsc70 and Hsp90 functions. Cytotoxic activity follows Hsc70-mediated escape of RTA from an otherwise destructive pathway facilitated by Hsp90. We demonstrate a role for cytosolic chaperones, proteins typically associated with folding nascent proteins, assembling multimolecular protein complexes and degrading cytosolic and stalled, cotranslocational clients, in a toxin triage, in which both toxin folding and degradation are initiated from chaperone-bound states

Cytosolic chaperones influence the fate of a toxin dislocated from the endoplasmic reticulum

The plant cytotoxin ricin enters target mammalian cells by receptor-mediated endocytosis and undergoes retrograde transport to the endoplasmic reticulum (ER). Here, its catalytic A chain (RTA) is reductively separated from the cell-binding B chain, and free RTA enters the cytosol where it inactivates ribosomes. Cytosolic entry requires unfolding of RTA and dislocation across the ER membrane such that it arrives in the cytosol in a vulnerable, nonnative conformation. Clearly, for such a dislocated toxin to become active, it must avoid degradation and fold to a catalytic conformation. Here, we show that, in vitro, Hsc70 prevents aggregation of heat-treated RTA, and that RTA catalytic activity is recovered after chaperone treatment. A combination of pharmacological inhibition and cochaperone expression reveals that, in vivo, cytosolic RTA is scrutinized sequentially by the Hsc70 and Hsp90 cytosolic chaperone machineries, and that its eventual fate is determined by the balance of activities of cochaperones that regulate Hsc70 and Hsp90 functions. Cytotoxic activity follows Hsc70-mediated escape of RTA from an otherwise destructive pathway facilitated by Hsp90. We demonstrate a role for cytosolic chaperones, proteins typically associated with folding nascent proteins, assembling multimolecular protein complexes and degrading cytosolic and stalled, cotranslocational clients, in a toxin triage, in which both toxin folding and degradation are initiated from chaperone-bound states

Searching for life with rovers: exploration methods and science results from the 2004 field campaign of the “Life in the Atacama” project and applications to future Mars Missions

LITA develops and field tests a long-range automated rover and a science payload to search for microbial life in the Atacama. The Atacama's evolution provides a unique training ground for designing and testing exploration strategies and life detection methods for the search for life on Mars

First Production and Detection of Cold Antihydrogen Atoms

The ATHENA experiment recently produced the first atoms of cold antihydrogen. This paper gives a brief review of how this was achieved.Comment: Invited talk at Int. Conf. on Low Energy Antiprotons 2003 (LEAP03), to be published in NIM

Normal tau polarisation as a sensitive probe of CP violation in chargino decay

CP violation in the spin-spin correlations in chargino production and subsequent two-body decay into a tau and a tau-sneutrino is studied at the ILC. From the normal polarisation of the tau, an asymmetry is defined to test the CP-violating phase of the higgsino mass parameter \mu. Asymmetries of more than \pm70% are obtained, also in scenarios with heavy first and second generation sfermions. Bounds on the statistical significances of the CP asymmetries are estimated. As a result, the normal tau polarisation in the chargino decay is one of the most sensitive probes to constrain or measure the phase \phi_\mu at the ILC, motivating further detailed experimental studies.Comment: 20 pages, 10 figures, gzipped tar fil