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Author(s):  
Habib Rahman ◽  
Nicki Cornford

Rationale, aims and objectives: Clinical incident reports are the primary means by which UK hospitals are alerted to avoidable harm in healthcare. However, data demonstrating the patterns in real-world reporting by healthcare workers have never been published in the UK. Though this journal has previously published survey data describing the discrepancies between respondents’ own behaviour compared to the incidence of perceived avoidable harm, we set out to collect data on actual reporting patterns between healthcare workers. Given the concerns raised by Robert Francis following the Mid-Staffordshire Inquiry, we specifically wished to examine the rate of reporting of doctors compared to other healthcare workers. Methods: We selected for incidents causing at least ‘moderate’ levels of harm, theorising that such levels of harm are most likely to be noticed by doctors. Data from 2011 to 2019 from the clinical governance departments of 2 NHS hospitals was requested and all available data subsequently charted. Results: This is the first study examining NHS incident reporting patterns in the medical profession. We demonstrated a stark level of underreporting of clinical incidents causing harm ranging from ‘moderate’ to death by doctors. This was particularly dramatic at the non-consultant grade level. In 1 hospital, only 2 deaths were reported by non-consultant grade doctors in 6 years. Notably 1 hospital had not stored any incident reporting data until 2017. Conclusion: The reporting behaviour of doctors has not significantly changed despite the Francis Reports. This could be improved by creating incentives for doctors to engage with patient safety initiatives and disclosure of error, as well as the use of automated systems.



Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1137
Author(s):  
Boxu Xu ◽  
Chao Song ◽  
Jun Song ◽  
Rui Huang ◽  
Juncheng Liu ◽  
...  

In this paper, a series of Rb+-doped Er3+/Yb3+–Y2O3 films were synthesized via a sol-gel method and spin coating. The structure and morphology of the samples were investigated by X-ray diffraction and scanning electron microscopy. The Rb+-doped films with nanoparticles, in the size range of 20–40 nm, were obtained. The spectroscopic analysis of the samples was investigated by using the emission spectra and the intensity of luminescence. All the samples exhibited a green emission ascribed to 2H11/2/4S3/2 to 4I15/2 of Er3+ and a red one ascribed to 4F9/2 and its stark level to 4I15/2 of Er3+. As the Rb+ concentration increased, the intensities of the green light and red light were enhanced 16.97- and 5.81-fold relative to that of the undoped sample. Moreover, by controlling the Rb+ concentration, the samples were capable of generating color-tunable luminescence from red to green linearly. The tunable emission was caused by the change of ion distribution ratio in 4F7/2(Er) and 4F9/2(Er) levels. The results suggest that the as-prepared Rb+-doped Er3+/Yb3+–Y2O3 films have a great potential for applications of luminescence.



2020 ◽  
pp. 93-226
Author(s):  
Alexander A. Kaminskii


2020 ◽  
Author(s):  
Abbie S. Ganas ◽  
Elena Dobretsova ◽  
Anupum Pant ◽  
Baptiste Journaux ◽  
Xiaojing Xia ◽  
...  

<div>Although solid-state laser-refrigeration recently has been demonstrated to reach cryogenic temperatures in vacuum, to date the solid-state laser refrigeration of materials at elevated pressure conditions has remained unexplored. Here we demonstrate the laser cooling of ytterbium-doped yttirum-lithium-fluoride (10%Yb<sup>3+</sup>:YLiF<sub>4</sub>, or Yb:YLF)</div><div>>17K below room temperature at pressures >4 GPa in a diamond anvil cell using lithium fluoride and ice-VII as a quasi-hydrostatic pressure media. Temperature measurements are quantified using a ratiometric-thermometry approach involving a Boltzmann fit to excited states distribution through 4f-4f Stark-level transitions from the Yb<sup>3+</sup> ions that occur between the <sup>2</sup>F<sub>5/2</sub> and <sup>2</sup>F<sub>7/2</sub> manifolds. At pressures between 7 and 12 GPa the YLF grains are observed to undergo a martensitic phase transition from a tetragonal scheelite phase (space group I41/a, Z = 4, No. 88) to a monoclinic fergusonite phase (space group I2/a, Z = 4, No. 15) which modifies the crys-</div><div>tal field splitting of the ground- and excited- state manifolds, but is observed to not eliminate laser cooling. Solid-state laser refrigeration at extreme pressures could allow researchers to use rapid photothermal cycling to explore temperature-dependent properties of materials, including electronic-structure phase-transitions, without the need for external cryostats.</div>



2020 ◽  
Author(s):  
Abbie S. Ganas ◽  
Elena Dobretsova ◽  
Anupum Pant ◽  
Baptiste Journaux ◽  
Xiaojing Xia ◽  
...  

<div>Although solid-state laser-refrigeration recently has been demonstrated to reach cryogenic temperatures in vacuum, to date the solid-state laser refrigeration of materials at elevated pressure conditions has remained unexplored. Here we demonstrate the laser cooling of ytterbium-doped yttirum-lithium-fluoride (10%Yb<sup>3+</sup>:YLiF<sub>4</sub>, or Yb:YLF)</div><div>>17K below room temperature at pressures >4 GPa in a diamond anvil cell using lithium fluoride and ice-VII as a quasi-hydrostatic pressure media. Temperature measurements are quantified using a ratiometric-thermometry approach involving a Boltzmann fit to excited states distribution through 4f-4f Stark-level transitions from the Yb<sup>3+</sup> ions that occur between the <sup>2</sup>F<sub>5/2</sub> and <sup>2</sup>F<sub>7/2</sub> manifolds. At pressures between 7 and 12 GPa the YLF grains are observed to undergo a martensitic phase transition from a tetragonal scheelite phase (space group I41/a, Z = 4, No. 88) to a monoclinic fergusonite phase (space group I2/a, Z = 4, No. 15) which modifies the crys-</div><div>tal field splitting of the ground- and excited- state manifolds, but is observed to not eliminate laser cooling. Solid-state laser refrigeration at extreme pressures could allow researchers to use rapid photothermal cycling to explore temperature-dependent properties of materials, including electronic-structure phase-transitions, without the need for external cryostats.</div>



Author(s):  
A.A. Andronov ◽  
A.V. Ikonnikov ◽  
K.V. Maremianin ◽  
V.I. Pozdnjakova ◽  
Y.N. Nozdrin ◽  
...  

AbstractNarrow band emissions at 2.6–2.8 THz are observed out of liquid helium cooled 1 mm disk chips prepared of a wafer with the very low n type doped weak barrier GaAs–GaAlAs superlattice of 1000 periods. The emissions are at about 8.0–18.0 V pulsed voltage applied to the chips in region of the chips positive DC differential conductivity that guaranties absence of inhomogeneous electric field domains in the chips. The emission frequency bands are estimated with a cyclotron resonance filter; the measurements show that the band width is of about that of the THz quantum cascade laser. By using long voltage pulses the chip heating above 100 K is achieved without substantial change in emission power. We speculate that the emission is super luminescence (amplification) of whispering gallery modes in the chips as a result of inverted Wannier-Stark level transitions under bias. The results are the first world demonstration of THz stimulated emission in a simple superlattice within region of positive DC differential conductivity; they give strong impetus for development of THz and higher frequency sources based on such simple superlattices; the sources should well compete with the THz quantum cascade lasers in particular at elevated temperatures.



2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Muhammad Hassyakirin Hasim ◽  
Irman Abdul Rahman ◽  
Sapizah Rahim ◽  
Muhammad Taqiyuddin Mawardi Ayob ◽  
Shamellia Sharin ◽  
...  

Gadolinium oxysulfide nanophosphors (Gd2O2S-NPs) have been successfully synthesized using γ-irradiation and hydrogenation treatment. The primary stage of Gd2O2S-NPs synthesis was carried out using various doses of γ-irradiation to form diverse sizes of Gd2(SO4)3 precursor, followed by hydrogenation treatment at 900°C for 2 hours to form Gd2O2S-NPs. Then, the nanophosphors were characterized for the structure, morphology, and luminescence properties through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and photoluminescence spectrometer (PL). Pure hexagonal phase of Gd2O2S-NPs was obtained with high crystallinity and without any impurities. The morphologies were observed from grain-like nanostructures transformed to spherical shape as the irradiation dose reached 40 kGy. Besides, Gd2O2S-NPs which were prepared at highest irradiation dose of 40 kGy show highest intensity of emission peak at 548 nm and corresponded to Stark level transition from the GJ6 state of Gd3+ ion. It can be emphasized that the different doses of γ-irradiation influenced the nucleation event of Gd2(SO4)3 precursor thus affecting the morphology and size particles of Gd2O2S-NPs. Hence, from the results, it can be suggested that Gd2O2S-NPs can be a promising host for optical applications.



2015 ◽  
Vol 92 (3) ◽  
Author(s):  
Limei Wang ◽  
Hao Zhang ◽  
Linjie Zhang ◽  
Georg Raithel ◽  
Jianming Zhao ◽  
...  




2013 ◽  
Vol 40 (7) ◽  
pp. 0702008
Author(s):  
丁欣 Ding Xin ◽  
张海永 Zhang Haiyong ◽  
盛泉 Sheng Quan ◽  
李斌 Li Bin ◽  
尚策 Shang Ce ◽  
...  


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