THE EFFECT OF NOTCHES ON THE FATIGUE LIFE OF A NICKEL-BASE GAS TURBINE DISK MATERIAL

Gas turbine disks carry significant load under high temperatures and may be subject to fatigue failure. Disks contain several notches in the form of the fir tree blade attachments. Low cycle fatigue tests were performed on blunt notch compact tension specimens made from alloy 718. The results indicated that notch support needed to be incorporated not to cause an overly conservative life prediction. The notch support diminished as the plastic strain range decreased, indicating that notch support is only present in the low cycle fatigue regime. A critical distance approach was applied to account for the notch support. An equation relating the critical distance to the notch root stress was derived. The chosen life model was formulated in terms of a variation on the Smith–Watson–Topper (SWT) parameter. The modified SWT parameter taken at the critical distance was used in a life model calibrated for smooth specimens to successfully predict the fatigue life of notched specimens

DECREASING COMPLEXITY OF THE ON-SITE CONSTRUCTION PROCESS USING PREFABRICATION: A CASE STUDY

ABSTRACT Implementing prefabrication is by many seen as means to improve construction in terms of managing uncertainties and productivity. However, regarding Swedish civil engineering works this has not been adequately documented to date. This case study uses Value Stream Mapping (VSM) to document the construction of a semiprefabricated superstructure. The intention of the project is to investigate if the bridge construction process becomes less complex to manage and control when using prefabrication instead of traditional on-site construction. By relocating parts of traditional on-site construction to a factory, the time spent on site performing traditional work tasks such as constructing formwork, mounting and fixing of rebar and casting concrete, could be decreased. Nevertheless, mapping the process revealed shortcomings such as problems placing the prefabricated beams onto the on-site constructed plate structures and also that clear communication between actors tend to increase in importance when choosing prefabrication as construction method. Results from the VSM show that the semi-prefabricated superstructure, future state, became less complex compared to current state construction and also 75% quicker to construct on-site. By redesigning the bridge to eliminate some of the infant "diseases", prefabrication will become more common in the future of small bridge construction in Sweden

Plasma proteomics in CML patients before and after initiation of tyrosine kinase inhibitor therapy reveals induced Th1 immunity and loss of angiogenic stimuli

Background and aims: The simultaneous measurement of many proteins is now possible using multiplex assays. In this pilot study we investigated a total of 124 proteins in plasma from chronic myeloid leukemia (CML) patients with the purpose of identifying proteins that are differently expressed at diagnosis and after tyrosine kinase inhibitor (TKI) treatment initiation. Methods: Samples were taken from 14 CML patients at diagnosis and after three months of TKI treatment (imatinib or dasatinib). Samples were analyzed by Mesoscale Discovery, Myriad RBM MAP technology and Olink Proseek. Results: Multiple plasma proteins were differentially expressed before and after initiation of TKI therapy. Protein patterns demonstrated a possible shift towards Th1-immunity and reduced angiogenic stimuli. Further, some plasma proteins were identified that can be of potential interest to study further for biologic, prognostic or therapeutic significance such as E-selectin, uPAR, growth hormone and carbonic anhydrase IX. Conclusions: Plasma proteomics seems feasible and useful in CML patients, both for studying patterns of protein expression and for identifying single proteins differentially expressed before and after treatment. Plasma proteomics may be useful to map disease activity and biological processes. Hence, plasma proteomics can be used to understand drug mechanisms and treatment responses in CML. (C) 2016 Elsevier Ltd. All rights reserved.Peer reviewe

Investigation of late-cycle soot oxidation using laser extinction and in-cylinder gas sampling at varying inlet oxygen concentrations in diesel engines

[EN] This study focuses on the relative importance of O-2 and OH as oxidizers of soot during the late cycle in diesel engines, where the soot oxidation is characterized in an optically accessible engine using laser extinction measurements. These are combined with in-cylinder gas sampling data from a single cylinder engine fitted with a fast gas-sampling valve. Both measurements confirm that the in-cylinder soot oxidation slows down when the inlet concentration of O-2 is reduced. A 38% decrease in intake O-2 concentration reduces the soot oxidation rate by 83%, a non-linearity suggesting that O-2 in itself is not the main soot oxidizing species. Chemical kinetics simulations of OH concentrations in the oxidation zone and estimates of the OH-soot oxidation rates point towards OH being the dominant oxidizer.The authors gratefully acknowledge the Swedish Energy Agency, the Competence Center for Combustion Processes KCFP (Project number 22485-3), and the competence center METALUND funded by FORTE for financially supporting this research. The authors acknowledge Volvo AB for providing the gas-sampling valve and personally Jan Eismark (Volvo AB) and Mats Bengtsson (Lund University) for their technical support.Gallo, Y.; Malmborg, VB.; Simonsson, J.; Svensson, E.; Shen, M.; Bengtsson, P.; Pagels, J.... (2017). Investigation of late-cycle soot oxidation using laser extinction and in-cylinder gas sampling at varying inlet oxygen concentrations in diesel engines. Fuel. 193:308-314. https://doi.org/10.1016/j.fuel.2016.12.013S30831419

An Internet-based emotion regulation intervention versus no intervention for non-suicidal self-injury in adolescents:a statistical analysis plan for a feasibility randomised clinical trial

BACKGROUND: Non-suicidal self-injury (NSSI) has a lifetime prevalence of 17% in adolescents in the general population and up to 74% in adolescents with psychiatric disorders. NSSI is one of the most important predictors of later suicidal behaviour and death by suicide. The TEENS feasibility trial was initiated to assess the feasibility and safety of Internet-based Emotion Regulation Individual Therapy for Adolescents (ERITA) as an add-on to treatment as usual in 13–17-year-old patients with NSSI referred to the Child and Adolescent Mental Health Services. METHODS: The TEENS feasibility trial is a randomised clinical trial with a parallel-group design. The trial intervention is an 11-week online therapy which is tested as an add-on to treatment as usual versus treatment as usual. The primary feasibility outcomes are the fraction of participants who (1) completed 12 weeks of follow-up interview or assessment, (2) consented to inclusion and randomisation out of all eligible participants, and (3) were compliant with the experimental intervention, assessed as completion of at least six out of eleven modules in the programme. Since this is a feasibility trial, we did not predefine a required sample size. The exploratory clinical outcome, the frequency of NSSI episodes, assessed using Deliberate Self-Harm Inventory – Youth version (DSHI-Y), at the end of intervention, is planned to be the future primary outcome in a larger pragmatic definitive randomised clinical trial. After completion of the feasibility trial, blinded data will be analysed by two independent statisticians blinded to the intervention, where ‘A’ and ‘B’ refer to the two groups. A third party will compare these reports, and discrepancies will be discussed. The statistical report with the analyses chosen for the manuscript is being tracked using a version control system, and both statistical reports will be published as a supplementary material. Based on the final statistical report, two blinded conclusions will be drawn by the steering group. DISCUSSION: We present a pre-defined statistical analysis plan for the TEENS feasibility trial, which limits bias, p-hacking, data-driven interpretations. This statistical analysis plan is accompanied by a pre-programmed version-controlled statistical report with simulated data, which increases transparency and reproducibility. TRIAL REGISTRATION: ClinicalTrials.govNCT04243603. Registered on 28 January 2020 SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-021-05406-2

RIFEL - Ripple and Electromagnetic Fields in Electric Vehicles

The electrical system in an electrified vehicle consists of high voltage (HV) components interacting in a complex way. The switching interaction in the power electronics results in ripple causing electromagnetic fields, disturbing other electronics and degradation of components. An overview of this can first be obtained when a physical system is built which could lead to unintentional over- or under dimensioning of HV components. This lack of information within the electrical system can lead to late verifications in the project causing substantial cost if changes are needed. This project aims at improving early evaluation of new concepts, create tools and build the necessary competence for a virtual system model that includes the key HV components: battery, electrical motor and power electronics, a simple load along with cable and connectors. This virtual model shall be able to simulate voltage and current ripple generated by the power electronics, initially in a frequency range up to 100 kHz. Results from the simulations shall be presented both in time and frequency domain as well as be expressed in RMS values for easier comparison to measured results. Some of the more important findings are briefly summarised below;For the high voltage battery, the electrical characteristics up to a frequency of roughly 1000 Hz was well determined using an impedance spectroscopy instrument at cell level and then multiplied by the numbers of cells.\ua0 However for finding the impedance behaviour for frequencies above 1000 Hz, the determination must be done on the battery pack level since bus bars and other component in the complete battery pack will be dominating in this frequency range. From measurements of differential mode impedance in high voltage cables it is found that it is important that the mutual inductance between the centre conductor and shield is included in the model to describe cable impedance below 10 kHz properly.The control of the inverter is very important for the overall behaviour and in this project SVM was used which has been shown to give the lowest current and voltage ripple of the traditional switching schemes. And for the machine model, the temperature variations must be taken into account since the machine parameters has been found to vary with ~20 % over the specified temperature range.The system model is found to agree well with rig measurements well up to 1 MHz with regards to both currents and voltages at the DC and AC sides. Furthermore, measurements in a real car match those in the rig. For time domain simulations, it was decided to use Ansys Simplorer since it can handle the inverter and the electrical machine simulations very well and for frequency domain simulations, it was decided to use LTspice since it is freeware, has support for AC-sweeps, improved switching compared to other SPICE-simulators, and is easy to use.Magnetic field simulations have been calculated and compared to measurements in the driveline rig at Chalmers. It was a good match across the investigated frequency range 10 Hz to 100 kHz.In this project, only internally developed component models were considered. To expand the functionality of the system modelling tool, international interface standards such as the Functional Mockup Interface (FMI) need to be investigated. Consequently, it would be a good idea to include additional automotive OEMs as well as suppliers and software vendors in future research collaborations

Dasatinib induces fast and deep responses in newly diagnosed chronic myeloid leukaemia patients in chronic phase : clinical results from a randomised phase-2 study (NordCML006)

Peer reviewe

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection