Concept and challenges of delivering preventive and care services in prehospital emergency medical service: A qualitative study

Background and purpose: Prehospital emergency medical service (EMS) is an important part of the health care system. Today, the need for integrated emergency care services and delivering qualified preventive and care services felt more than before in accidents and emergencies. This survey aimed to investigate the views of emergency medical personnel on the concept and nature of preventive and care services and current challenges in delivering these services in prehospital EMS centers in Golestan province, Iran. Materials and methods: A qualitative study was done with 16 emergency medical personnel working in EMS sites in Golestan province using purposeful sampling. Data was collected by semistructured interview guide and framework analysis was implemented to analyze the data. Results: Two general themes were identified including 1) the concept of preventive and care services in the EMS and 2) the challenges in providing qualified services in the EMS sites in Golestan province. Also, five sub-themes and 12 subclasses were determined. Conclusion: To enhance and promote services, the EMS system of Golestan province need reforms in organizational structure, laws and administrative regulations, training programs, the system of monitoring and evaluation of personnel, also provision of equipment and manpower and provision of personnel amenities to improve the staff performance. Furthermore, it is necessary to boost emergency services at the community level through training people and enhancing collaboration and participation with other organizations. © 2015, Mazandaran University of Medical Sciences. All rights reserved

Wind load design considerations for the elevation and azimuth drives of a heliostat

This paper investigated the dynamic fluctuations of the high-frequency surface pressure and force measurements on an instrumented scale-model heliostat within a turbulent ABL generated in a wind tunnel. Peak aerodynamic load coefficients on the model heliostat calculated following the equivalent static wind load method were consistent with previous wind tunnel studies in the literature. The dynamic analysis of the hinge, azimuth and overturning moments in the current study showed that there are a range of critical load cases and heliostat configurations that need to be considered to investigate the dynamic loading on the elevation and azimuth drives of a heliostat. Quasi-steady variation of the fluctuating peak loads following a Gaussian distribution was found to under-predict the maximum hinge and overturning moments in operating and stow configurations. It is therefore recommended that the analysis of instantaneous loads on the elevation drive and pedestal foundation is carried out for an improved estimation of the heliostat design wind loads.Matthew Emes, Azadeh Jafari, Maziar Arjomand

Wavefront-guided laser-assisted subepithelial keratectomy in low myopia, myopic astigmatism and high myopia

AIM: To compare the safety, efficacy, predictability, stability and complications of wavefront-guided laser-assisted subepithelial keratectomy (LASEK) in low myopia, myopic astigmatism and high myopia correction. METHODS: A retrospective analysis of 416 eyes were assigned to 3 groups: 159 eyes with low myopia (LM) and mean refractive spherical equivalent (MRSE) of -3.68±1.33 dioptre (D); 161 eyes with myopic astigmatism (MA) and MRSE of -5.99±2.24D and mean cylinder of 2.41±1.07D; and 96 eyes with high myopia (HM) and MRSE of -7.41±0.80D. After an epithelial flap creation, a wavefront-based excimer laser ablation was performed. Safety, efficacy, predictability and stability were evaluated at day 10, 2, 6 and 12mo postoperatively. RESULTS: At 12mo, the MRSE was -0.36±0.31D in LM group, 0.15±0.41D in MA group and 0.58±0.68D in HM group. The uncorrected visual acuity (UCVA) was 20/20 in 90.60 of patients in LM group, 78.90 in MA group and 67 in HM group. Efficacy indices were 0.98, 1.04 and 0.92 in LM, MA and HM groups, respectively. Safety indices were 1.00, 1.07 and 1.05 in LM, MA and HM respectively. Five eyes (3.1) in the LM group gained 1 line. Forty-four eyes (27.3) in MA gained 1-3 lines and eighteen eyes (19.2) of HM group gained 1-2 lines of BSCVA. Only 2 eyes in LM group developed corneal haze. There were not statistically significant differences in efficacy and safety indices amongst three groups. CONCLUSION: Wavefront-guided LASEK is an effective and safe procedure for the treatment of LM, MA, and HM.although in myopic astigmatism the predictability, efficacy and safety indices had been better. ©, 2015, International Journal of Ophthalmology (c/o Editorial Office). All right reserved

Hinge and overturning moments due to unsteady heliostat pressure distributions in a turbulent atmospheric boundary layer

Available online 09 October 2019Non-uniform pressure distributions on the heliostat surface due to turbulence in the atmospheric boundary layer (ABL) have a significant impact on the maximum bending moments about the hinge of and pedestal base of a conventional pedestal-mounted heliostat. This paper correlates the movement of the centre of pressure due to the mean and peak pressure distributions with the hinge and overturning moment coefficients using high-frequency pressure and force measurements on a scale-model heliostat within two simulated ABLs generated in a wind tunnel. The positions of the centre of pressure were calculated for a range of heliostat elevation-azimuth configurations using a similar analogy to those in ASCE 7-02 for monoslope-roof buildings, ASCE 7-16 for rooftop solar panels, and in the literature on flat plates. It was found that the maximum hinge moment is strongly correlated to the centre of pressure movement from the heliostat central elevation axis. Application of stow and operating load coefficients to a full-scale 36m² heliostat showed that the maximum hinge moment remains below the stow hinge moment at maximum operating design gust wind speeds of 29 m/s in a suburban terrain and 33 m/s in a desert terrain. The operating hinge moments at elevation angles above 45° are less than 60% of the stow loads with a constant 40 m/s design wind speed. The results in the current study can be used to determine heliostat configurations and appropriate design wind speeds in different terrains leading to the maximum design wind loads on the elevation drive and foundation.Matthew J. Emes, Azadeh Jafari, Farzin Ghanadi, Maziar Arjomand

The Fire Simulation in a Road Tunnel

Fire behaviour, especially its interaction with ventilation system in tunnels, is still a challenging issue for road tunnel designers .This paper presents the results of a study investigating the influence of a road tunnel ventilation system, on conventional fires. For this purpose, a 25 MW fire corresponding to a conventional fire in a road tunnel was simulated using 2D numerical modelling, for transient viscous multi-component gas at low Mach numbers to study smoke and heat propagation within a road tunnel under fire .Complete Navier-Stocks and Reynolds equations were solved using developed algorithm of numerical modelling .The results from a series of calculations were compared with results of experimental researches to examine the accuracy and stability of the calculations .The comparisons showed that the algorithm provided a good description of physical processes in selected class of flow. It was also concluded that calculation accuracy is not lower than those obtained from established simulation software programs . The stability and good convergence of the algorithm was confirmed by separate calculations with different grid patterns for the tunnel under consideration .The results revealed that the temperature at tunnel wall may rise up to 900oC. The concentration of smoke may also increase up to 95 %with a burning truck .Results were applied to assess the ventilation system designed for a new long road tunnel in case of fire .The results from the study along with other information were applied to assess the designed ventilation system and to establish the suitable fire fighting and rescue plan

Latest developments in silica-based thermoluminescence spectrometry and dosimetry

Using irradiated doped-silica preforms from which fibres for thermoluminescence dosimetry applications can be fabricated we have carried out a range of luminescence studies, the TL yield of the fibre systems offering many advantages over conventional passive dosimetry types. In this paper we investigate such media, showing emission spectra for irradiated preforms and the TL response of glass beads following irradiation to an Am-241-Be neutron source located in a tank of water, the glass fibres and beads offering the advantage of being able to be placed directly into liquid. The outcomes from these and other lines of research are intended to inform development of doped silica radiation dosimeters of versatile utility, extending from environmental evaluations through to clinical and industrial applications. (C) 2015 Elsevier Ltd. All rights reserve

Anisotropy in mechanical properties and fracture behavior of an oxide dispersion Fe20Cr5Al alloy

Anisotropy of fracture toughness and fracture behavior of Fe20Cr5Al oxide dispersion-strengthened alloy has been investigated by means of compression tests, hardness tests, and wedge splitting test. The results show a small effect of the compression direction on yield strength (YS) and strain hardening. The YS is minimum for longitudinal direction and maximum for the tangential direction. The transverse plastic strain ratio is similar for tangential and longitudinal directions but very different from that in normal direction. Hardness depends on the indentation plane; it is lower for any plane parallel to the L-T plane and of similar magnitude for the other orthogonal planes, i.e., the L-S and T-S planes. Macroscopically, two failure modes have been observed after wedge-splitting tests, those of LS and TS specimens in which fracture deviates along one or two branches normal to the notch plane, and those of LT, TL, SL, and ST specimens in which fracture propagates along the notch plane. Besides LT and TL specimens present delaminations parallel to L-T plane. Both, the fracture surface of branching cracks and that of the delaminations, show an intergranular brittle fracture appearance. It is proposed that the main cause of the delamination and crack branching is the alignment in the mesoscopic scale of the ultrafine grains structure which is enhanced by the 〈110〉- texture of the material and by the presence in the grain boundaries of both yttria dispersoids and impurity contaminations. An elastoplastic finite element analysis was performed to study what stress state is the cause of the branches and delaminations. It is concluded that the normal to the crack branches and/or the shear stress components could determine the crack bifurcation mechanism, whereas the delamination it seems that it is controlled by the magnitude of the stress component normal to the delamination plane. © The Minerals, Metals & Materials Society and ASM International 2014.Peer Reviewe

Clinical efficacy of convalescent plasma for treatment of COVID-19 infections: Results of a multicenter clinical study

Since Dec. 2019 the new coronavirus (SARS-CoV-2) has infected millions and claimed life of several hundred thousand worldwide. However, so far no approved vaccine or drug therapy is available for treatment of virus infection. Convalescent plasma has been considered a potential modality for COVID-19 infection. One hundred eighty-nine COVID-19 positive patients including 115 patients in plasma therapy group and 74 patients in control group, registered in the hospitals with confirmed COVID-19 infection, entered this multi-center clinical study. Comparison of outcomes including all-cause mortality, total hospitalization days and patients� need for intubation between the two patient groups shows that total of 98 (98.2 ) of patients who received convalescent plasma were discharged from hospital which is substantially higher compared to 56 (78.7 ) patients in control group. Length of hospitalization days was significantly lower (9.54 days) in convalescent plasma group compared with that of control group (12.88 days). Only 8 patients (7) in convalescent plasma group required intubation while that was 20 in control group. This clinical study provides strong evidence to support the efficacy of convalescent plasma therapy in COVID-19 patients and recommends this treatment for management of these patients. Clinical efficacy, immediate availability and potential cost effectiveness could be considered as main advantages of convalescent plasma therapy. © 2020 Elsevier Lt

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters