216 research outputs found
The Impact of Preheat on 2205 Duplex Stainless Steel Welds
The goal of this project is to determine the relationship between preheat temperature and phase balance of austenite and ferrite in the heat affected zone (HAZ) of a dissimilar thickness weld made of Sandvik SAF 2205 duplex stainless steel (DSS). Various preheat temperatures were applied (no preheat, 63°C, 98 °C, 141 °C, 181 °C, and 214 °C) to a 2-inch thick plate that was welded to a 0.072-inch thin sheet, with a 0.125-inch standoff, using manual gas tungsten arc welding (GTAW). Welding variables (voltage, amperage, and travel speed) were recorded and thermocouples were placed along the backside of the weld, underneath a purging tube of pure argon. For each preheat temperature, a sample was sectioned between the thermocouples and underwent metallography. Phase analysis and microhardness testing were performed at five locations across the weld: thick plate, thick plate HAZ, weldment, thin sheet HAZ, and thin sheet. The percentage of austenite and ferrite was determined using IQ Material software. Microhardness testing was performed in accordance with ASTM E384-17. Welding parameters and thermocouple data were used to calculate heat input and the resulting cooling rates. Results indicated the weldment and HAZ zones did not sufficiently improve their phase balance as preheat temperature increased. Inconsistencies in the welding parameters resulted in a variance of heat input between preheat temperatures, which influenced cooling rates. Since the cooling rate directly affects the phase balance, a relationship between preheat temperature and phase balance could not be determined
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Membrane Hsp70 â a novel target for the isolation of circulating tumor cells after epithelial-to-mesenchymal transition
The presence of circulating tumor cells (CTCs) in the peripheral blood is a pre-requisite for progression, invasion, and metastatic spread of cancer. Consequently, the enumeration and molecular characterization of CTCs from the peripheral blood of patients with solid tumors before, during and after treatment serves as a valuable tool for categorizing disease, evaluating prognosis and for predicting and monitoring therapeutic responsiveness. Many of the techniques for isolating CTCs are based on the expression of epithelial cell surface adhesion molecule (EpCAM, CD326) on tumor cells. However, the transition of adherent epithelial cells to migratory mesenchymal cells (epithelial-to-mesenchymal transition, EMT)âan essential element of the metastatic processâis frequently associated with a loss of expression of epithelial cell markers, including EpCAM. A highly relevant proportion of mesenchymal CTCs cannot therefore be isolated using techniques that are based on the âcaptureâ of cells expressing EpCAM. Herein, we provide evidence that a monoclonal antibody (mAb) directed against a membrane-bound form of Hsp70 (mHsp70)âcmHsp70.1âcan be used for the isolation of viable CTCs from peripheral blood of tumor patients of different entities in a more quantitative manner. In contrast to EpCAM, the expression of mHsp70 remains stably upregulated on migratory, mesenchymal CTCs, metastases and cells that have been triggered to undergo EMT. Therefore, we propose that approaches for isolating CTCs based on the capture of cells that express mHsp70 using the cmHsp70.1 mAb are superior to those based on EpCAM expression
Prognosis of Sentinel Node Staged Patients with Primary Cutaneous Melanoma
Background: This study investigated survival probabilities and prognostic factors in sentinel lymph node biopsy (SLNB) staged patients with cutaneous melanoma (CM) with the aim of defining subgroups of patients who are at higher risk for recurrences and who should be considered for adjuvant clinical trials.\ud
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Methods: Patients with primary CM who underwent SLNB in the Department of Dermatology, University of Tuebingen, Germany, between 1996 and 2009 were included into this study. Survival probabilities and prognostic factors were evaluated by Kaplan-Meier and multivariate Cox proportional hazard models.\ud
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Results: 1909 SLNB staged patients were evaluated. Median follow-up time was 44 months. Median tumor thickness was 1.8 mm, ulceration was present in 31.8% of cases. The 5-year Overall Survival (OS) was 90.3% in SLNB negative patients (IB 96.2%, IIA 87.0%, IIB 78.1%, IIC 72.6%). Patients with micrometastases (stage IIIA/B) had a 5-year OS rate of 70.9% which was clearly less favorable than for stages IâII. Multivariate analysis revealed tumor thickness, ulceration, body site, histopathologic subtype and SLNB status as independent significant prognostic factors.\ud
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Conclusion: Survival rates of patients with primary CM in stages IâII were shown to be much more favorable than previously reported from non sentinel node staged collectives. For future clinical trials, sample size calculations should be adapted using survival probabilities based on sentinel node staging
Managing the link and strengthening transition from child to adult mental health Care in Europe (MILESTONE): Background, rationale and methodology
Background: Transition from distinct Child and Adolescent Mental Health (CAMHS) to Adult Mental Health Services (AMHS) is beset with multitude of problems affecting continuity of care for young people with mental health needs. Transition-related discontinuity of care is a major health, socioeconomic and societal challenge globally. The overall aim of the Managing the Link and Strengthening Transition from Child to Adult Mental Health Care in Europe (MILESTONE) project (2014-19) is to improve transition from CAMHS to AMHS in diverse healthcare settings across Europe. MILESTONE focuses on current service provision in Europe, new transition-related measures, long term outcomes of young people leaving CAMHS, improving transitional care through 'managed transition', ethics of transitioning and the training of health care professionals. Methods: Data will be collected via systematic literature reviews, pan-European surveys, and focus groups with service providers, users and carers, and members of youth advocacy and mental health advocacy groups. A prospective cohort study will be conducted with a nested cluster randomised controlled trial in eight European Union (EU) countries (Belgium, Croatia, France, Germany, Ireland, Italy, Netherlands, UK) involving over 1000 CAMHS users, their carers, and clinicians. Discussion: Improving transitional care can facilitate not only recovery but also mental health promotion and mental illness prevention for young people. MILESTONE will provide evidence of the organisational structures and processes influencing transition at the service interface across differing healthcare models in Europe and longitudinal outcomes for young people leaving CAMHS, solutions for improving transitional care in a cost-effective manner, training modules for clinicians, and commissioning and policy guidelines for service providers and policy makers
German S3 guideline "actinic keratosis and cutaneous squamous cell carcinoma" â long version of the update 2023
Actinic keratosis (AK) are common lesions in light-skinned individuals that can potentially progress to cutaneous squamous cell carcinoma (cSCC). Both conditions may be associated with significant morbidity and constitute a major disease burden, especially among the elderly. To establish an evidence-based framework for clinical decision making, the guideline âactinic keratosis and cutaneous squamous cell carcinomaâ was updated and expanded by the topics cutanepus squamous cell carcinoma in situ (Bowenâs disease) and actinic cheilitis. This guideline was developed at the highest evidence level (S3) and is aimed at dermatologists, general practitioners, ear nose and throat specialists, surgeons, oncologists, radiologists and radiation oncologists in hospitals and office-based settings, as well as other medical specialties, policy makers and insurance funds involved in the diagnosis and treatment of patients with AK and cSCC
Cytotoxicity of rhein, the active metabolite of sennoside laxatives, is reduced by multidrug resistance-associated protein 1
Anthranoid laxatives, belonging to the anthraquinones as do anthracyclines, possibly increase colorectal cancer risk. Anthracyclines interfere with topoisomerase II, intercalate DNA and are substrates for P-glycoprotein and multidrug resistance-associated protein 1. P-glycoprotein and multidrug resistance-associated protein 1 protect colonic epithelial cells against xenobiotics. The aim of this study was to analyse the interference of anthranoids with these natural defence mechanisms and the direct cytotoxicity of anthranoids in cancer cell lines expressing these mechanisms in varying combinations. A cytotoxicity profile of rhein, aloe emodin and danthron was established in related cell lines exhibiting different levels of topoisomerases, multidrug resistance-associated protein 1 and P-glycoprotein. Interaction of rhein with multidrug resistance-associated protein 1 was studied by carboxy fluorescein efflux and direct cytotoxicity by apoptosis induction. Rhein was less cytotoxic in the multidrug resistance-associated protein 1 overexpressing GLC4/ADR cell line compared to GLC4. Multidrug resistance-associated protein 1 inhibition with MK571 increased rhein cytotoxicity. Carboxy fluorescein efflux was blocked by rhein. No P-glycoprotein dependent rhein efflux was observed, nor was topoisomerase II responsible for reduced toxicity. Rhein induced apoptosis but did not intercalate DNA. Aloe emodin and danthron were no substrates for MDR mechanisms. Rhein is a substrate for multidrug resistance-associated protein 1 and induces apoptosis. It could therefore render the colonic epithelium sensitive to cytotoxic agents, apart from being toxic in itself
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