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To audit UK radiology departmental protocols related to the prevention of Iodine-based contrast media (ICM) adverse drug reactions (ADRs) and to assess their compliance with the Royal College of Radiologists (RCR) endorsed Royal Australian and New Zealand College of Radiologists' 2018 Iodinated Contrast Guidelines. Questionnaires were sent to all UK acute National Health Service (NHS) providers treating adult patients with an audit lead registered with the RCR (162 providers encompassing 211 hospital radiology departments). The questionnaire included three main sections: renal function screening, renal protection regimens, and hypersensitivity reactions prevention and follow-up. Data collection was conducted between April and July 2022. Sixty-one per cent (129/211) of departments responded, representing 67% of eligible providers. An independent imaging services provider supplied one additional set of data (n= 130 overall). Of the responding departments, for post-contrast acute kidney injury (PC-AKI), 41% and 56% had the recommended risk assessment for inpatients and outpatients, respectively. Renal function testing was often over-utilised, and their results were applied improperly. Sixty-eight per cent of departments used the advised threshold for considering renal protection. For hypersensitivity reactions, 9% of departments had the correct risk assessment. Thirty-six per cent of departments had the correct risk mitigation protocol for identified high-risk patients. The documentation and follow-up for hypersensitivity reactions were similarly inadequate. Local protocols on preventing ICM ADRs were largely non-compliant with RCR guidelines. Departments need to update their protocols in line with current evidence to avoid iatrogenic morbidity or unnecessary tests and over-precaution. • The availability of renal protection protocols greatly improved since the 2015 audit. • Protocols on prevention and follow-up for contrast hypersensitivity were very poor. • Current protocols require updating to avoid unnecessary iatrogenic morbidity. • Need for risk stratified renal function testing, and improved allergy testing. [ABSTRACT FROM AUTHOR]

The plastic deformation of biodegradable zinc alloy with 1 wt% of magnesium by hydrostatic extrusion (HE) was performed. The influence of severe plastic deformation on the microstructure and mechanical properties of ZnMg was investigated. Cumulative extrusion with total true strain ε = 3.33 was applied to the homogenised material. Microstructure observations carried out using scanning electron microscope (SEM)/ Electron Backscatter Diffraction (EBSD) methods, as well as static tensile tests, revealed outstanding results. After the deformation, grain refinement causing substantial strengthening of the material was observed. An average grain size equal to 700 nm and YS = 316 MPa, UTS = 435 MPa with ε f = 35% was obtained. These results indicate that the HE method enables the grain refinement level and mechanical properties of ZnMg to be obtained, which would not be possible with conventional methods of plastic deformation. The properties of the Zn alloy after HE satisfy the requirements for bioresorbable stent applications. [ABSTRACT FROM AUTHOR]

The annealing behavior of AA1050 aluminum alloy deformed by equal-channel angular pressing (ECAP) was studied experimentally. The material was subjected to extrusion through die with channels intersecting at an 90° angle. Samples were pressed for up to 8 passes using route BC, then cut into slices and subsequently annealed for 1 hour at temperatures from 100°C to 350°C. Hardness measurements were performed on each slice. Microstructure of material was analyzed in the longitudinal section by means of Electron Backscatter Diffraction system in a scanning electron microscope (EBSD/SEM). From the obtained sets of Kikuchi diffraction patterns orientation maps and Image Quality maps were determined. Grain size, disorientation distributions and crystallographic texture were also estimated. ECAP caused significant improvement of hardness, with stabilization after 4 passes. Refinement of microstructure was obtained with the increasing amount of passes. Material properties were stable during annealing at temperatures lower than 150°C. Annealing at higher temperatures caused a decrease in hardness corresponding to an increase of the grain size. [ABSTRACT FROM AUTHOR]

Observations of refined microstructure of Commercial Purity titanium for applications in biomedical devices has been carried out. Refinement of titanium microstructure has been performed in process with complex strain scheme. Materials investigated in this work were: Commercial Purity titanium grade 2 and grade 4. Samples of as received materials were subjected to plastic deformation in complex loading process of extrusion combined with oscillation twisting (KoBo extrusion). Both types of samples were deformed in single step of extrusion, in temperature of 450 °C, with extrusion ratio 19.14 and 12.25 for grade 2 titanium and grade 4 titanium, respectively. Initial mean grain diameter for both types of materials was approximately 30 μm. Samples were investigated by means of crystal orientation microscopy. In both cases considerable microstructure refinement has been observed. Microstructures of deformed samples are heterogenous and consist of both elongated and fine equiaxed grains. Elongated grains (lamellae) are separated by High Angle Grain Boundaries and feature internal structure with subgrains and dislocation walls. Grain refinement is stronger in material with higher extrusion ratio and mean grain diameter in this case is equal to 1.48 μm compared to 8.07 μm. in material with lower extrusion ratio. Mean misorientation angle (24° and 27° for grade 4 and grade 2 titanium) indicates high fraction of HAGBs in microstructures of KoBo deformed samples. Misorientation fluctuations inside grains have been analyzed and distinct curvature of crystal lattice have been observed. Hardness of samples after plastic deformation increased from 174.6±3.4 and 234.9±3.5 to 205.0±3.2 and 251.2±2.2 for titanium grade 2 and grade 4 respectively. [ABSTRACT FROM AUTHOR]

Pure aluminium (6N) and commercially pure aluminium (99.7) was deformed by KOBO method. Microstructure and texture of both materials after deformation was analyzed by means of scanning and transmission electron microscopy. Advanced methods of crystallographic orientations measurements like Electron Backscatter Diffraction - EBSD (SEM) and microdiffraction (TEM) was used. Grain size distribution and misorientation between grains in cross and longitudinal sections of the samples were analyzed. Differences in size and homogeneity of the grains were observed in both materials. Pure aluminium was characterized by larger grain size in both sections of extruded material. Whereas commercially pure aluminium reveals smaller grain size and more homogeneous and stable microstructure. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to review the MRI examinations of a large group of low-energy trauma patients in whom pelvic MRI had detected radiographically occult fractures, in order to characterize prevailing fracture patterns and determine how often co-existing proximal femoral and pelvic fractures were observed.Methods: All patients having pelvic MRI over 5 years were identified. Word-search software selected 269 MRI reports containing the term ‘fracture’. Further scrutiny identified 168 with diagnosis of fracture. MRI request and imaging record review identified 102 low-energy trauma cases that had MRI for clinical suspicion of fracture despite normal radiographs. Sixty-six cases were excluded for the following reasons: no expressed clinical suspicion of occult fracture; history suggesting high-energy trauma;skeletal co-morbidity hindering acute fracture identification;interval more than 2 weeks between radiographs and MRI. The 102 study MRI examinations, which employed a limited two-sequence protocol, were reviewed. Any fracture that had not been appreciated on radiographs was recorded and characterized as femoral, pelvic, or co-existing femoral and pelvic fractures.Results: The 102 study cases had a median age of 82 years.The median interval between pelvic radiographs and MRI was 3 days. MRI showed undiagnosed femoral fracture in 48/102 cases (47.1%), sacral fracture in 41/102 (40.2%),and pubic fracture in 55/102 (53.9%). In 11/102 cases(10.8%), MRI showed undiagnosed fractures of both proximal femur and pelvic ring (seven sacral, six pubic bone, two other site fractures). In 10/11 cases with coexisting femoral and pelvic fractures, the femoral fracture was incomplete.Conclusions: Limited pelvic MRI found a high prevalence of radiographically occult femoral and pelvic fractures in low-energy trauma patients, with clinical suspicion of fracture despite normal radiographs. Co-existing occult femoral and pelvic ring fractures were commonly observed, and in such cases, the femoral fracture was likely to be incomplete and multiple pelvic fractures were typically present. [ABSTRACT FROM AUTHOR]

Abstract: In order to apply Laser Induced Breakdown Spectroscopy (LIBS) for diagnostics of fuel retention and removal and wall composition in ITER it is necessary to validate the method in terms of repeatability and quality of its results for mixed, especially ITER relevant materials and its sensitivity to thin layers which contain small amounts of retained fuel. The experiments, which are within the scope of this paper were carried out at the IPPLM Warsaw to assess the method for the laser treatment of ASDEX Upgrade (AUG) strike-point tiles and calibrated C:W:Al samples prepared by the Institute of Electronic Materials Technology (IEMT). The samples under investigation contained hydrogen isotopes in the ITER-relevant mixed material layer (as the Beryllium analogue, Al was used). An electrostatic ion energy analyzer was used as the auxiliary diagnostics. The results proved that optical spectroscopy, although not straightforward in use, can give reliable results even for small amounts of fuel present in the mixed-material layer, although more effort should be put into investigating calibrated samples, to optimize the method itself and to yield a quantitative measure of fuel retention. [Copyright &y& Elsevier]

The aim of the present work was to observe changes in precipitations during annealing after cold-rolling. Series of the samples from cold-rolled AA6013 were prepared and compared to undeformed samples. The samples were annealed at the temperatures equal to 260, 490 °C for undeformed state and at 280, 360, and 530 °C for cold-rolled state. For investigation thin foils were prepared. Chemical composition and crystal structure of precipitates was analysed and described using transmission electron microscopy imaging, X-ray energy-dispersive spectroscopy and selected-area diffraction techniques. The researches indicated that low annealing temperatures caused dissolution of metastable β and Q phases. With increasing temperature there also occurred growth of Q phase. At highest annealing temperatures there were noticed precipitations of β phase again. Microstructural observation also revealed an impact of those particles on recrystallization processes. [ABSTRACT FROM AUTHOR]

The paper presents application of combined in situ annealing and orientation mapping technique for investigation the microstructural changes in the aluminium alloy 6013 with bimodal distribution of the second phase particles during recovery and recrystallization processes. Information about grain distribution, misorientation between grains, size and shape of the grains at each stage of recrystallization process were obtained. Complexity of the experimental procedure is defined and discussed in order to avoid artificial results. Although the article described the advantages and disadvantages of those method used in transmission electron microscopy and scanning electron microscopy in the work the results from scanning electron microscopy/electron backscattering diffraction in situ heating experiments are highlighted. Obtained data are in a good agreement with previous transmission electron microscopy and calorimetry studies. [ABSTRACT FROM AUTHOR]

Polarimetric optical fiber sensors possess possibility of temperature compensation, dynamic and integral system of strain monitoring, as well as low cost of photo-detecting elements. In the paper we present results of the sensor analysis with different kinds of birefringent optical fibers leading to an optimal setup for dynamic strain monitoring in composite materials. A great attention is put on parameters of the light sources like coherence and width of spectrum and their influence on dynamics of the strain sensor. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 66-year-old male with non-specific acute abdominal pain, central abdominal tenderness, and guarding. He was diagnosed with acute appendicitis confirmed through a computed tomography (CT) scan during subsequent laparoscopic surgery and showed an incidental abnormality in his left lower lumbar region. He had an iliolumbar hernia that contains retroperitoneal fat in descending colon and underwent surgery using synthetic mesh.

In this work samples of commercial purity grade 2 titanium were severely deformed by three different extrusion techniques: equal-channel angular pressing (ECAP), extrusion through oscillating die (KOBO), and hydrostatic extrusion (HE). Resulting microstructures and mechanical properties of processed titanium samples are studied and compared with regard to potential application as a material for dental implants. The obtained results demonstrate the effect of different strain paths, involved by three applied deformation methods, on microstructure refinement, mechanical properties and textures of the studied material. Heterogeneous microstructures with bimodal grain size distributions are observed for all deformation techniques in the examined material, however differences in their internal structures and grain boundary distributions point to different grain refinement mechanisms. The fraction of ultra-fine grains is the highest in titanium deformed by HE. Also the internal grain fragmentation is the most important after HE deformation. This leads to the best mechanical and microstructural properties obtained in this type of deformation. Consequently, the HE process seems to be very interesting for production of material for medical implants. [ABSTRACT FROM AUTHOR]

VMAT-based single-isocenter multiple-targets (SIMT) are sensitive to rotational uncertainties and leads to greater possibility of dose coverage loss for off-axis targets. Instead of treating all targets in one plan, it is common practice to separate them into multiple groups based on their distance. It ensures the targets are within reasonable distance and therefore increases robustness, but resulting in increased planning complexity and lower delivery efficiency. Studies have yet to evaluate the impact of separating targets for multiple scattered targets. This work aims to investigate the dosimetric and robustness impact of separating strategy. 10 patients (95 metastases, 4-19 per patient) were retrospectively included. The PTV was 1mm margin expansion to GTV. Two sets of plans were created using HyperArc technique: (1) A single SIMT plan (non-separated) included all PTVs. The PTV to isocenter distance ranged from 2.4cm to 9.5cm (mean 5.7cm). (2) Multiple SIMT plans (separated) so in each plan PTV center to isocenter distance was < = 5cm. 3-4 plans were needed to treat all targets. The mean dose, V6Gy and V12Gy of brain were calculated. The dose coverage against setup uncertainty was evaluated by shifting/rotating dose distribution around the isocenter. 1mm translations in three directions and 1° rotations around three axes (total 12 scenarios) were simulated. The dosimetric changes of GTVs were evaluated using V100% (relative volume covered by prescribed dose) and D99% (relative minimum dose delivered to 99% of the GTV). The non-separated plan increased brain mean dose from separated plan by an average of 22.3cGy (std 15.9cGy). The brain V6Gy V12Gy were increased by 3.3cc and 0.86cc on average in the non-separated plans. Across all 12 1mm/1° translation/rotation uncertainty cases, the average GTV [V100%, D99%] is [99.8%, 103.2%] in non-separated plans, compared with [99.9%, 109.0%] in separated plans. Under worst situation, 6/95 GTVs in nonseparated plans have D99% < 95% (lowest 90.5%), while only one GTV in separated plans have D99% < 95% (lowest 94.4%). Compared with separating targets based on their distances, treating all targets in one plan has similar brain dose sparing with slightly increased low dose distribution. Considering setup uncertainty, non-separated plans maintained GTV dose coverage with average V100% similar to separated plans but degraded D99%. The delivery time of non-separated plans is 3-4 times faster than separated plans. [ABSTRACT FROM AUTHOR]

Silver nanoparticle (Ag-NP) containing antibacterial micro-arc oxidation (MAO) coatings have already been synthesized over titanium-based materials via the MAO process employed in silver acetate (AgC2H3O2) containing electrolyte. However, the way of incorporation and in-situ formation of Ag-NPs within the MAO coating have not been documented yet. Present work was initiated to reveal the mechanism of Ag-NP formation within the MAO coatings. Thus, the structure of the MAO coating fabricated on commercial purity titanium in the AgC2H3O2-containing electrolyte was investigated by electron microscopy techniques. To this end, the cross-sectional high-resolution electron microscopy studies were carried out on lamella cut out with the focused ion beam technique, and these investigations were backed by X-ray photoelectron spectroscopy measurements of chemical composition on the surface of the MAO coating. These studies revealed that Ag is dispersed in the form of nanoparticles throughout the coating and that a higher density was confirmed closer to the micro-pores. [ABSTRACT FROM AUTHOR]

This study investigates the influence of plastic deformation of commercially pure titanium (cp-Ti) substrates on the tribological performance of micro-arc oxidation (MAO) coatings. Hydrostatic extrusion (HE) was employed to refine the microstructure of cp-Ti, producing ultrafine-grained (UFG) titanium, which was compared with coarse-grained (CG) cp-Ti. Both substrates were subjected to the MAO process, and the fabricated MAO coatings were analysed through X-ray diffraction (XRD), electron microscopy techniques (SEM and TEM), energy dispersive spectrometry, atomic force microscopy (AFM), and tribological testing (hardness, scratch and wear tests). The results show that HE-treated cp-Ti substrates promoted faster and thicker MAO coating formation, with superior adhesion and tribological properties compared to CG cp-Ti. The UFG substrate led to increased hardness and wear resistance, largely due to the higher density of grain boundaries and electrical resistance of the substrate, which accelerated oxide layer growth. It has been demonstrated that plastic deformation of the substrate via HE significantly enhances the performance of MAO coatings, providing improved surface protection for biomedical applications. • MAO coatings were deposited on coarse- and ultra-fine grained cp-Ti substrates. • Plastic deformation of cp-Ti substrate significantly accelerates coating growth. • Substrate HAGB and defect density influence current density during MAO process. • MAO coating on extruded cp-Ti presents higher crystallinity and rutile content. • Better adhesion and wear resistance was proved for MAO coating on extruded cp-Ti. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of the deformation degree and aging time on the mechanical properties and microstructure of AA7050 alloy static tensile test, microhardness measurements, calorimetric analysis and observations of the microstructure in the transmission and scanning electron microscope were carried out. For study a series of cylindrical specimens with an initial diameter of about 3 mm were used. The samples were saturated at a temperature of 470° C for 1 hour and quenched in water. The samples were then subjected to deformation up to the three levels: 0%, 5% and 10%. Deformed samples was artificially aged at 120°C for 6 hours, 12 hours, 24 hours and 72 hours. The results showed that the increase in the degree of deformation caused an increase in yield strength and a decrease in ductility. The longer aging time influenced on an increase in tensile strength, yield stress and microhardness and a decrease in ductility. An analysis of the precipitates present in the material was conducted. The highest value of yield strength equal 538 MPa with elongation 9.2% were obtained for sample pre-strained to 10% and aged for 24 hours. The obtained results showed that prolongation in aging time and use of pre-strain were beneficial for precipitation processes courses, consequently, for optimal mechanical properties of alloy 7050. [ABSTRACT FROM AUTHOR]

Analysis of the results of the microstructure and the mechanical properties change in AA1050 aluminum alloy of technical purity processed using ECAP (Equal Channel Angular Pressing) and KoBo deformation methods are presented in the paper.. ECAP process was performed according to Bc scheme in the range from 1 up to 10 passes. Changes of microstructure were analyzed using scanning electrone microscope equipped with electron backscattered diffraction (EBSD) system. Microstructure and fraction of high-angle grain boundaries in KoBo processed samples were similar to those observed in ECAP processed samples after four passes. The most significant microstructure refinement was observed in ECAP processed sample submitted to 10 passes. In ECAP method the systematic increase of mechanical properties was observed along with increase of deformation degree. [ABSTRACT FROM AUTHOR]

In the present work, the effect of the electric potential provided by the bipolar pulsed power supply during micro-arc oxidation of titanium in disodium hydrogen phosphate (Na 2 HPO 4) electrolyte on the microstructure and chemical composition of the formed oxide coating was studied. The surface topography and microstructure of obtained coatings were investigated using scanning and transmission electron microscopy. In addition, the chemical analysis was performed with two complementary methods: energy-dispersive X-ray spectroscopy and more accurate but surface-sensitive X-ray photoelectron spectroscopy. These investigations revealed the formation mechanism of the titanium oxide coating, depending on whether an anodic or cathodic cycle is forced by the power supply. During the anodic cycle, the simultaneous interaction of negatively charged O2− ions and HPO 4 2− anions with Ti4+ ions released from the substrate occurs. Introducing the cathodic cycle allows a small amount of Na to be incorporated into the coating material, mainly in the areas close to the porosity, which was not possible with the use of the direct current (DC) or unipolar pulsed power supply. Moreover, an increase in applied voltage increased rutile content and improved the crystallinity of the TiO 2 -based MAO coating. • Micro-arc oxidation of cp-Ti was performed in Na 2 HPO 4 -based electrolyte. • Crystalline (anatase+rutile)/amorphous (Ti(HPO 4) 2) coating formed in anodic cycle. • During cathodic cycle, a certain amount of Na (<1 at.%) was incorporated. • Na locates in areas close to pores (up to 10 at.%) due to attraction of Na+ cations. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of titanium rods deformed by hydrostatic extrusion (HE) in artificial saliva (Carter-Brugirard’s solution of pH 7.6) was investigated using open-circuit potentials (OCPs), (DC) potentiodynamic polarisation curves and (AC) electrochemical impedance spectroscopy (EIS) techniques. Various electrochemical parameters (corrosion potential E corr , corrosion current ( i corr ), polarisation resistance R p , charge transfer resistance R ct and oxide film resistance R f ) were analysed. Significant coherence was observed between results achieved from these procedures, i.e., all applied techniques showed the same trend for corrosion resistance. The obtained electrochemical data were then related to the microstructure parameters (crystallographic texture, grain size, grain boundary distribution and density) determined using the EBSD/SEM technique. It was found that the corrosion behaviour of titanium processed by the HE method was superior compared to the unprocessed Ti, and this was clearly dependent on the extrusion direction. The highest corrosion resistance was revealed for the HE-deformed Ti rod of the surface oriented longitudinal (parallel) to the extrusion direction. [ABSTRACT FROM AUTHOR]

Evolution of microstructure and texture of commercial purity (CP) titanium grade 2 during two-step deformation process was investigated in this work. Deformation technique utilized in first step of samples preparation was the KoBo type extrusion. In the second step, further deformation was performed by the cold rolling process in order to facilitate high level of grain refinement. After the first step of deformation microstructure of titanium sample consists of equiaxed grains with no internal structure, but with distinct distribution of grain sizes. Texture of KoBo extruded Ti sample is typical with 0001 basal planes oriented parallel to the extrusion direction. During the cold rolling microstructure is significantly refined. Some grains are elongated in the rolling direction, however most of the microstructure is occupied by fine grains with close to equiaxed shape. Almost 50% of the microstructure consists of highly refined fraction of grains with diameter below one micrometer. Analysis of microstructure suggest that refined grains are produced due to dynamic recrystallization that occurs both during KoBo and during subsequent cold rolling in the fine grained areas of KoBo extruded sample. [ABSTRACT FROM AUTHOR]

The microstructure and properties of cast and hot extruded zinc subjected to plastic deformation by conventional extrusion and by extrusion with a forward-backward rotating die (KoBo) were studied. KoBo significantly increased the mechanical properties of both initial materials compared with conventional extrusion. The improvement of the mechanical properties is related to the lower temperature at which the KoBo process can be carried out. Extrusion with a forward-backward rotating die leads to grain refinement and promotes the formation of a composite-like microstructure with a hard matrix, forming an interconnected network of boundaries filled with a softer phase. New areas of application for zinc obtained by the KoBo method are opened. [ABSTRACT FROM AUTHOR]

It is well known that dropwise condensation corresponds to a high heat transfer coefficient. The high performance enhancement of dropwise condensation in comparison to filmwise condensation is attributed to the ability of non-wetting droplets to be shed from the surface by gravity, therefore reducing the overall thermal resistance. The common treatments to carry out the hydrophobic surface for dropwise condensation are coating and structure. The improvement of heat transfer efficiency by combination of surface treatments with coating and groove structure has been proved compared of surface with single surface treatment by coating or groove structure. Based on this result, in this study presents a model developed to predict the heat transfer efficiency of dropwise condensation for surface with coating and groove structure features. The model is established by heat transfer though a single droplet with the drop size distribution. The heat transfer of single drop is not only analyzed as combination of thermal resistances, but also considered capillary effect of droplet due to groove geometry and properties of surface. In addition, the model results are validated with experimental data which is investigated by varied modification of vapor side metallic surface properties at low absolute pressure. It can be a reference to design industrial condensers of heat exchangers in the future. Further to optimize the surface properties and improve the higher heat transfer performance of dropwise condensation. [ABSTRACT FROM AUTHOR]

Development of new materials requires application of sophisticated techniques to characterize microstructure in a very detailed way. The combination of Electron Backscatter Diffraction (EBSD) and Energy Dispersive Spectrometry (EDS) with Focused Ion Beam (FIB) are excellent examples of such techniques. They are based on serial sectioning of chosen region in the investigated sample followed by data acquisition using the dual-beam scanning electron microscope equipped with both electron and ion columns. Three kinds of samples have been investigated: a) are anticorrosive Ni-Mo coating on ferritic steel; b) the oxidized Crofer22 APU ferritic stainless steel; c) the Al 6013 aluminum alloy after complex plastic deformation. The obtained results allowed to analyze crystalline morphology, distribution of precipitates as well as to reconstruct internal structure of grains and grains boundaries geometry. [ABSTRACT FROM AUTHOR]