275 research outputs found

    A comparative study of the surface glaze characteristics of concrete treated with CO2 and high power diode lasers. Part II: mechanical, chemical and physical properties

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    The hardened ordinary Portland cement (OPC) surface layer of concrete which was glazed using a CO2 and a high power diode laser (see Part I of this paper) has been tested in order to determine the mechanical, chemical and physical characteristics of the glazes. The work showed that the generation of the surface glazes resulted in improved mechanical, chemical and physical properties over the untreated OPC surface of concrete. However, differences in the performance of the CO2 and HPDL generated glazes were observed. These are believed to be due to the differences in the morphology and microstructure of the glazes generated as a result of the differing beam absorption characteristics of the two lasers. Life assessment testing revealed that the laser glazed OPC surfaces effected an increase in actual wear life of 1.3 to 17.7 times over the untreated OPC surface of concrete depending upon the corrosive environment

    Case Studies in Using MATLAB to Build Model Calibration Tools for Multiscale Modeling

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    This chapter illustrates the versatility of MATLAB for building interactive end-user software applications to support the pedagogy of a multiscale modeling approach to computational materials engineering. The case studies presented here demonstrate how preexisting codes that model complex material behavior, even if written in compiled computer languages such as Fortran or C++, may be utilized as computational libraries for model calibration software tools built with MATLAB. Intended for students in computational engineering (mechanics and materials), these tools execute on personal computers without MATLAB if the MATLAB Runtime shared libraries are installed. Publications coauthored by students using these tools to calibrate material models and to investigate the performance of engineering materials indicate that the tools enable advances in engineering design from a computational engineering perspective

    Timed up and go test and long-term survival in older adults after oncologic surgery

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    BACKGROUND: Physical performance tests are a reflection of health in older adults. The Timed Up and Go test is an easy-to-administer tool measuring physical performance. In older adults undergoing oncologic surgery, an impaired TUG has been associated with higher rates of postoperative complications and increased short term mortality. The objective of this study is to investigate the association between physical performance and long term outcomes. METHODS: Patients aged ≥65 years undergoing surgery for solid tumors in three prospective cohort studies, ‘PICNIC’, ‘PICNIC B-HAPPY’ and ‘PREOP’, were included. The TUG was administered 2 weeks before surgery, a score of ≥12 seconds was considered to be impaired. Primary endpoint was 5-year survival, secondary endpoint was 30-day major complications. Survival proportions were estimated using Kaplan-Meier curves. Cox- and logistic regression analysis were used for survival and complications respectively. Hazard ratios (aHRs) and Odds ratios (aOR) were adjusted for literature-based and clinically relevant variables, and 95% confidence intervals (95% CIs) were estimated using multivariable models. RESULTS: In total, 528 patients were included into analysis. Mean age was 75 years (SD 5.98), in 123 (23.3%) patients, the TUG was impaired. Five-year survival proportions were 0.56 and 0.49 for patients with normal TUG and impaired TUG respectively. An impaired TUG was an independent predictor of increased 5-year mortality (aHR 1.43, 95% CI 1.02-2.02). The TUG was not a significant predictor of 30-day major complications (aOR 1.46, 95% CI 0.70-3.06). CONCLUSIONS: An impaired TUG is associated with increased 5-year mortality in older adults undergoing surgery for solid tumors. It requires further investigation whether an impaired TUG can be reversed and thus improve long-term outcomes. TRIAL REGISTRATION: The PICNIC studies are registered in the Dutch Clinical Trial database at www.trialregister.nl: NL4219 (2010-07-22) and NL4441 (2014-06-01). The PREOP study was registered with the Dutch trial registry at www.trialregister.nl: NL1497 (2008-11-28) and in the United Kingdom register (Research Ethics Committee reference 10/H1008/59). https://www.hra.nhs.uk/planning-and-improving-research/application-summaries/research-summaries/?page=15&query=preop&date_from=&date_to=&research_type=&rec_opinion=&relevance=true. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12877-022-03585-4

    Long-Term Survival and Risk of Institutionalization in Onco-Geriatric Surgical Patients:Long-Term Results of the PREOP Study

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    OBJECTIVES: To evaluate long-term survival and institutionalization in onco-geriatric surgical patients, and to analyze the association between these outcomes and a preoperative risk score. DESIGN: Prospective cohort study with long-term follow-up. SETTING: International and multicenter locations. PARTICIPANTS: Patients aged 70 years or older undergoing elective surgery for a malignant solid tumor at five centers (n = 229). MEASUREMENTS: We assessed long-term survival and institutionalization using the Preoperative Risk Estimation for Onco-geriatric Patients (PREOP) score, developed to predict the 30-day risk of major complications. The PREOP score collected data about sex, type of surgery, and the American Society for Anesthesiologists classification, as well as the Timed Up & Go test and the Nutritional Risk Screening results. An overall score higher than 8 was considered abnormal. RESULTS: We included 149 women and 80 men (median age = 76 y; interquartile range = 8). Survival at 1, 2, and 5 years postoperatively was 84%, 77%, and 56%, respectively. Moreover, survival at 1 year was worse for patients with a PREOP risk score higher than 8 (70%) compared with 8 or lower (91%). Of those alive at 1 year, 43 (26%) were institutionalized, and by 2 years, almost half of the entire cohort (46%) were institutionalized or had died. A PREOP risk score higher than 8 was associated with increased mortality (hazard ratio = 2.6; 95% confidence interval [CI] = 1.7-4.0), irrespective of stage and age, but not with being institutionalized (odds ratios = 1 y, 1.6 [95% CI =.7-3.8]; 2 y, 2.2 [95% CI =.9-5.5]). CONCLUSION: A high PREOP score is associated with mortality but not with remaining independent. Despite acceptable survival rates, physical function may deteriorate after surgery. It is imperative to discuss treatment goals and expectations preoperatively to determine if they are feasible. Using the PREOP risk score can provide an objective measure on which to base decisions. J Am Geriatr Soc 68:1235–1241, 2020

    Quality of Life in Older Adults After Major Cancer Surgery:The GOSAFE International Study

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    Abstract Background Accurate quality of life (QoL) data and functional results after cancer surgery are lacking for older patients. The international, multicenter Geriatric Oncology Surgical Assessment and Functional rEcovery after Surgery (GOSAFE) Study compares QoL before and after surgery and identifies predictors of decline in QoL. Methods GOSAFE prospectively collected data before and after major elective cancer surgery on older adults (≥70 years). Frailty assessment was performed and postoperative outcomes recorded (30, 90, and 180 days postoperatively) together with QoL data by means of the three-level version of the EuroQol five-dimensional questionnaire (EQ-5D-3L), including 2 components: an index (range = 0-1) generated by 5 domains (mobility, self-care, ability to perform the usual activities, pain or discomfort, anxiety or depression) and a visual analog scale. Results Data from 26 centers were collected (February 2017-March 2019). Complete data were available for 942/1005 consecutive patients (94.0%): 492 male (52.2%), median age 78 years (range = 70-95 years), and primary tumor was colorectal in 67.8%. A total 61.2% of all surgeries were via a minimally invasive approach. The 30-, 90-, and 180-day mortality was 3.7%, 6.3%, and 9%, respectively. At 30 and 180 days, postoperative morbidity was 39.2% and 52.4%, respectively, and Clavien-Dindo III-IV complications were 13.5% and 18.7%, respectively. The mean EQ-5D-3L index was similar before vs 3 months but improved at 6 months (0.79 vs 0.82; P < .001). Domains showing improvement were pain and anxiety or depression. A Flemish Triage Risk Screening Tool score greater than or equal to 2 (odds ratio [OR] = 1.58, 95% confidence interval [CI] = 1.13 to 2.21, P = .007), palliative surgery (OR = 2.14, 95% CI = 1.01 to 4.52, P = .046), postoperative complications (OR = 1.95, 95% CI = 1.19 to 3.18, P = .007) correlated with worsening QoL. Conclusions GOSAFE shows that older adults’ preoperative QoL is preserved 3 months after cancer surgery, independent of their age. Frailty screening tools, patient-reported outcomes, and goals-of-care discussions can guide decisions to pursue surgery and direct patients’ expectations

    Oral Insulin

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    Oral insulin is an exciting area of research and development in the field of diabetology. This brief review covers the various approaches used in the development of oral insulin, and highlights some of the recent data related to novel oral insulin preparation

    Extensive necrosis of visceral melanoma metastases after immunotherapy

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    <p>Abstract</p> <p>Background</p> <p>The prognosis for metastatic melanoma remains poor even with traditional decarbazine or interferon therapy. 5-year survival is markedly higher amongst patients undergoing metastatectomy. Unfortunately not all are suitable for metastatectomy. Alternative agents for systemic therapy have, to date, offered no greater rates of survival beyond traditional therapy. A toll-like receptor 9 agonist, PF-3512676 (formerly known as CPG 7909) is currently being evaluated for its potential.</p> <p>Case presentation</p> <p>We present the case of a 54-year-old Caucasian male with completely resected metastatic cutaneous melanoma after immunotherapy. The patient initially progressed during adjuvant high-dose interferon, with metastases to the liver, spleen, and pelvic lymph nodes. During an 18-month treatment period with PF-3512676 (formerly known as CPG 7909), a synthetic cytosine-phosphorothioate-guanine rich oligodeoxynucleotide, slow radiologic disease progression was demonstrated at the original disease sites. Subsequent excision of splenic and pelvic nodal metastases was performed, followed by resection of the liver metastases. Histologic examination of both hepatic and splenic melanoma metastases showed extensive necrosis. Subsequent disease-free status was demonstrated by serial positron emission tomography (PET).</p> <p>Conclusion</p> <p>Existing evidence from phase I/II trials suggests systemic treatment with PF-3512676 is capable of provoking a strong tumor-specific immune response and may account for the prolonged tumor control in this instance.</p
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