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Purpose: The objective of this study is to analyse the appropriateness of lower extremity coputed tomography (CT) scans as performed in a large orthopaedic hospital. Material and methods: A total of 1410 CT scans acquired in the years 2014-2018 were analysed for compliance with the "Guidelines for Physicians Issuing Diagnostic Imaging Referrals" (iRefer). These guidelines were published by the Royal Radiologist Society and recommended for use by the Polish Medical Society of Radiology, the National Consultant for Radiology and Diagnostic Imaging, and the Minister of Health. In addition, the study involved the analysis of information provided on CT referrals by referring clinicians. Results: Nearly 21% of CT referrals were found to be unsubstantiated based on the diagnosis made by the referring physician, the body region of interest, and the clinical department. Most referrals identified as non-compliant with the guidelines were related to cancers followed by inflammatory conditions. The lowest number of unjustified exams was reported for endoprostheses and injury-related cases. Conclusions: The study revealed a significant degree of non-compliance with the diagnostic algorithm as defined in the iRefer guidelines, particularly in cases of cancers and inflammatory conditions. Consequently, the patient's exposure to ionizing radiation is increased. Incorrect decisions regarding the appropriate diagnostic imaging technique are founded on the lack of appropriate cooperation between the clinician and the radiologist, insufficiency or lack of information provided on the referral, as well as the defensive attitude of referring physicians. It is therefore necessary to change appropriate in-hospital management and cooperation models.

Purpose Identification of the group of patients meeting the criteria of a severe multiple trauma (polytrauma) among those admitted to the regional trauma centre and subjected to whole-body computed tomography (WBCT) due to injuries. Identification the patients for whom WBCT was the optimal choice. Material and methods Retrospective analysis of the data of 303 patients undergoing WBCT in the period 2015-2017 with assessment of the injury severity based on the abbreviated injury scale (AIS) and injury severity score (ISS). Results Among 303 patients undergoing WBCT due to trauma, multiple injuries with ISS > 15 were found in 74 individuals (24.4%). After excluding patients whose limb fractures increased ISS above 15, the group decreased to 63 patients (20.8%). For these patients, the WBCT may be described as the optimal imaging method at an early stage of management. Conclusions Trauma patients are too often qualified for WBCT. Exposure to a high dose of ionising radiation associated with this modality requires critical analysis of the scope of indications and rules of conduct for trauma teams.

In the work, an original method and a special modified device is presented enabling to determine welding conditions of hard deformable aluminium alloys. The main advantage of the proposed method is that it simulates conditions occurring in the welding chamber of the porthole dies. The weldability tests were performed for 5754 (3,5% Mg) and 5019 (5,5% Mg) alloys, in a wide range of temperatures and pressures. The microstructure and joints strength were examined. The welding conditions of AlMg alloys that allowed obtaining high-quality joints were determined. The obtained welding stress values will be the basis for extrusion porthole die design.

Each enterprise that concentrates on boosting its position on a market tries to optimize mechanisms of its activity. It can be realized mainly by development in such directions as extending shares on the market, cost reduction, introducing more effective methods of production and risk management. Increasing the level of customers’ satisfaction is reached by use of FMEA (Failure Mode and Effect Analysis) as a tool of continuous development of products and processes realized by conducting their cyclic analyses. Their results build a foundation for introducing new solutions as corrective actions that eliminate causes of defects and at the same time lead to process and product improvement.The advantages of FMEA have resulted in its implementation into nearly every branch of a modern industry, both for unitary and mass production. An example of application of FMEA in mass production is a production process of beverage cans. This process is multistage, extraordinarily precise, technologically complicated and burdened by a great amount of factors that hypothetically can cause defects.The application of proper preventive actions aimed at defining both potential and factual causes of defects is an essential element of increasing the effectiveness a of production line with the simultaneous production cost reduction and boosting the level of customer satisfaction.In the article, the use of FMEA in mass production on the basis of a beverage can manufacturing has been analysed. On its basis, the potential causes of defects have been isolated and eliminated.

Numerical simulations of drawing and redrawing process of forming cylindrical elements from thin sheets are complicated issues due to the problem with describing finite elements in the complex calculation model. This type of simulation require the creation of the rheological model including the forming limit curve, the true-stress-strain curve and anisotropy defined in various directions. In addition, it is necessary to design optimal geometry of the forming tools. FEM calculations have been performed for 3XXX series aluminum tape in cold-hardening state. The initial data, boundary conditions have been defined, as well as technological data concerning the sheets have been specified experimentally. Numerical analysis of thin aluminum sheet drawing and redrawing process has been analyzed for 3 various sheet thicknesses, i.e.: 0,250 mm , 0,240 mm , 0,230 mm. Currently, the industry uses mainly sheets of 0.250mm thickness. A few manufacturers of beverage cans use sheets of thickness0.240mm while the sheet of thickness 0.230mmis the innovation which manufacturers try to introduce into the industry to minimize the quantity of material. For the selected thickness the clearance between the punch and the die has been calculated as well as the optimum hold-down force. The influence of sheet thickness on the distribution of thinning along generating line has been examined. In order to determine the thinnest possible sheet for obtaining the optimal thickness of the final product, the thinning of drawpiece has been analyzed. Moreover the value of deformations has been compared to FLC curve as well as the intensity of the stresses generated in the bottom and on side walls of the cup has been examined.

Materials used for the production of aluminum beverage cans must meet strict strength and plastic requirements. Meeting these requirements by manufacturers ensures minimization of defects in optimized production line, trouble-free operation and good efficiency of production. Depending on some factors, such as: chemical composition of the 3104 aluminum alloy, sheet rolling method, lubricant layer and cooling method, the final product may be characterized by different mechanical parameters. In this study properties of six types of sheets from four different suppliers have been measured. Thickness distributions have been analyzed both on the width and length of the supplied coils. Sets of samples have been prepared for the research, cut out from the coil in three directions 0°, 45° and 90° of the rolling direction. On the basis of the uniaxial tension tests, yield strength, tensile strength, elastic modulus and elongation have been determined. The results have been summarized taking into account their variable values depending on sampling directions. Forming limit curves have been defined for the examined sheets. In order to identify the effect of selected data on wall thickness of both final and semi-products, thickness measurements have been conducted for the drawn cups and cans on different forming stages.

The paper presents the results of a study to designate the optimal conditions for the powder mixtures extrusion through porthole die to ensure high quality welds. Conditions for obtaining the profiles of powder mixtures with a high degree of compaction and good quality welds have been determined based on mathematical and physical modelling. Modelling studies have been confirmed in laboratory and industrial trials.

In industrial practice, where the amount of products produced in a minute is calculated in hundreds of units, the ironing process of thin-walled cylindrical shell products is carried out with very high speed. In the multi-stage forming process it is important to ensure the stability of parameters of the raw material. Properties of input sheets are defined in international standards, but after the rolling process the properties of input tapes may be various while still in the acceptable tolerance. Differentiation of properties of sheets has a significant impact on the progress of the examined process. The multi-stage forming process requires raw material with a high susceptibility to deformation and an adequate level of plasticity margin. In this study tapes of equal thickness and similar chemical composition from various suppliers have been analyzed. Selected aluminum alloys sheet are currently used in Europe in production of beverage packaging. On the basis of uniaxial tension test results, plasticity margin for a selected tape has been determined. Deformation range and plasticity margin have been analyzed in relation to the stability of production process Defining the correlation between identified strength parameters and the stability of production line allowed to examine the impact of plasticity margin for effectiveness and efficiency of the process. In mass production, each break in machine work results in loss of millions of units. The analysis allowed to compare the value of plasticity indicators of the raw tape deformability in the complex process of forming thin-walled cylindrical shell products and influence for increase the efficiency and reduction of defects.

BACKGROUND: The purpose of the study was to evaluate the percentage of unjustified examinations among all the CT and MRI studies performed by two radiology departments and to determine the types of examinations which are most commonly carried out unnecessarily. MATERIAL AND METHODS: Three radiologists assessed the justification of CT and MRI examinations performed during a period of 14 days based on the referrals. The radiologists assessed 799 referrals for CT scans (847 examinations of a particular part of the body) and 269 MRI referrals (269 examinations). The criteria for justification were: medical expertise and the guidelines. During the first stage radiologists divided the examinations into 3 groups: justified, unjustified and the examinations of questionable justification. The second step was to determine the reasons why the studies were considered as unjustified or of questionable justification. RESULTS: 73 of 1116 examinations (6.54%) were considered to be unjustified or of a questionable justification. There were 59 CT scans (59/847=6.97%) and 14 MRI studies (14/269=5.20%). The most common reasons to consider them as unjustified or of questionable justification were: inadequate method of diagnostic imaging chosen as a first-line tool and lacking or insufficient clinical details. CONCLUSIONS: In our investigation 6.54% of both CT and MRI examinations were considered as unjustified or of questionable justification, which is lower than described in other studies (from 7% to 26%). The assessment was based only on referrals, therefore a total share of these examinations is likely to be higher.

Background: Concern exists that the prolonged application of immunomodulators to treat atopic dermatitis may cause systemic immunosuppression. Aims: In a 7-month, multicentre, randomised, controlled trial, we investigated the equivalence of response to vaccination against meningococcal serogroup C disease with a protein-conjugate vaccine in children (2–11 years) with moderate to severe atopic dermatitis, by applying either 0.03% tacrolimus ointment (TAC-O; n = 21) or a hydrocortisone ointment regimen (HC-O; n = 111). Methods: TAC-O was applied twice daily (bid) for 3 weeks, and thereafter daily until clearance. 1% hydrocortisone acetate (HA) for head/neck and 0.1% hydrocortisone butyrate ointment for trunk/limbs was applied bid for 2 weeks; thereafter HA was applied bid to all affected areas. At week 1, patients were vaccinated with protein-conjugate vaccine against meningococcal serogroup C, and challenged at month 6 with low dose meningococcal polysaccharide vaccine. The control group (44 non-atopic dermatatits children) received the primary vaccination and challenge dose. Assessments were made at baseline, weeks 1 and 5, and months 6 and 7. The primary end point was the percentage of patients with a serum bactericidal antibody (SBA) titre ⩾8 at the week 5 visit. Results: The response rate (patients with SBA titre ⩾8) was 97.5% (confidence interval (CI) approximately 97.3 to 100), 99.1% (94.8 to 100) and 97.7% (93.3 to 100) in the TAC-O, HC-O and control groups, respectively. Conclusions: The immune response to vaccination against meningococcal serogroup C in children with atopic dermatitis applying either 0.03% TAC-O or HC is equivalent. Ointment application does not affect the immediate response to vaccination, generation of immune memory or humoral and cell-mediated immunity.