Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Review”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43

Cadmium and atherosclerosis: A review of toxicological mechanisms and a meta-analysis of epidemiologic studies

Cadmium has been proposed to be the one of the factors of atherosclerosis development, although the existing data are still controversial. The primary objective of the present study is the review and the meta-analysis of studies demonstrating the association between Cd exposure and atherosclerosis as well as review of the potential mechanisms of such association. We performed a systematic search in the PubMed-Medline database using the MeSH terms cadmium, cardiovascular disease, atherosclerosis, coronary artery disease, myocardial infarction, stroke, mortality and humans up through December 20, 2017. Elevated urinary Cd levels were associated with increased mortality for cardiovascular disease (HR = 1.34, 95% CI: 1.07–1.67) as well as elevated blood Cd levels (HR = 1.78, 95% CI: 1.24–2.56). Analysis restricted to never smokers showed similar, though more imprecise, results. Consistently, we also observed an association between Cd exposure markers (blood and urine) and coronary heart disease, stroke, and peripheral artery disease. Moreover, Cd exposure was associated with atherogenic changes in lipid profile. High Cd exposure was associated with higher TC levels (OR = 1.48, 95% CI: 1.10–2.01), higher LDL-C levels (OR = 1.31, 95% CI 0.99–1.73) and lower HDL-C levels (OR = 1.96, 95% CI: 1.09–3.55). The mechanisms of atherogenic effect of cadmium may involve oxidative stress, inflammation, endothelial dysfunction, enhanced lipid synthesis, up-regulation of adhesion molecules, prostanoid dysbalance, as well as altered glycosaminoglycan synthesis.

54 ENVIRONMENTAL SCIENCES↗

Ambient ozone exposure and mental health: A systematic review of epidemiological studies

Highlights: • 31 studies concerned about ozone and mental health outcomes were reviewed. • Inconclusive evidence on ozone and autism, cognitive decline, depression and suicide. • Currently evidence is inconclusive and more high quality studies are needed. An increasing number of studies have suggested adverse effects of air pollution on mental health. Given the potentially negative impacts of ozone exposure on the immune and nervous system driven from animal experiments, ozone might also affect mental health. However, no systematic synthesis of the relevant literature has been conducted yet. This paper reviews the studies that assessed the link between ozone exposure and mental health thus far.

54 ENVIRONMENTAL SCIENCES↗

Update on thirdhand smoke: A comprehensive systematic review

Highlights: • THS consists of tobacco pollutants that remain in dust, air and on surfaces. • A systematic literature review was done for thirdhand smoke as a term. • Thirdhand smoke exposure results in toxicity. • -Long-term effects of THS exposure remain unknown and more research is needed. The objective of this study is to perform a comprehensive review of the literature about thirdhand smoke (THS).

54 ENVIRONMENTAL SCIENCES↗

Shedding light on the economic costs of long-duration power outages: A review of resilience assessment methods and strategies

Here this paper provides a literature review of methods and modeling techniques to estimate the cost of power system outages, along with the value of outage mitigation or system resilience. Regulators, policymakers, and infrastructure owners have a growing need to understand the methods for estimating the benefits of resilience improvements of electric infrastructure against natural and man-made disasters. There is a broad literature that estimates the cost of short-duration outages and a small but developing literature on estimating the cost of long-duration outages. This article reviews the models used to estimate the cost of outages and discusses their relative strengths. Additionally, this paper identifies key questions from stakeholders regarding resilience investment and maps them to the relevant models that would help answer them. We include recommendations for future work to include recent advances in regional economic modeling that can estimate region and demographic-specific costs and the distributional consequences of potential resilience projects.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Physical solvents and techno-economic analysis for pre-combustion CO 2 capture: A review

In this manuscript we review the use, development, and economic performance of physical solvents for pre-combustion CO 2 capture from high pressure H 2 rich syngas streams. Commercially available physical solvents are presented, followed by an assessment of the ideal properties that are important for development of novel solvents for CO 2 capture from high-pressure syngas streams. To compare the technical and economic performance of traditional and novel physical solvents, a review of the methods, assumptions and models used in techno-economic analysis (TEA) studies was conducted. It was found that, although some novel solvents show promising technical performance in the laboratory (e.g., high CO 2 absorption capacity and low vapor pressure), other issues (e.g., solvent viscosity and cost) may limit their industrial applications. Process simulations were useful tools for modeling the technical performance of processes using traditional and novel solvents. However, model predictions are most reliable when the methods and correlations used to develop the process simulation are validated with representative experimental data, in particular highly accurate baseline models are required for fair comparison among physical solvents. The key inputs and assumptions in pre-combustion CO 2 capture TEAs have also been summarized. Some studies showed that the promising technical performance of novel physical solvents can be offset by the high and often unknown costs of these solvents. Future development of novel physical solvents for pre-combustion CO 2 capture will benefit from more studies that conduct in-depth techno-economic analysis, specifically with validated process simulations and transparent economic models.

42 ENGINEERING↗

Second Solid Cancers After Radiation Therapy: A Systematic Review of the Epidemiologic Studies of the Radiation Dose-Response Relationship

Rapid innovations in radiation therapy techniques have resulted in an urgent need for risk projection models for second cancer risks from high-dose radiation exposure, because direct observation of the late effects of newer treatments will require patient follow-up for a decade or more. However, the patterns of cancer risk after fractionated high-dose radiation are much less well understood than those after lower-dose exposures (0.1-5 Gy). In particular, there is uncertainty about the shape of the dose-response curve at high doses and about the magnitude of the second cancer risk per unit dose. We reviewed the available evidence from epidemiologic studies of second solid cancers in organs that received high-dose exposure (>5 Gy) from radiation therapy where dose-response curves were estimated from individual organ-specific doses. We included 28 eligible studies with 3434 second cancer patients across 11 second solid cancers. Overall, there was little evidence that the dose-response curve was nonlinear in the direction of a downturn in risk, even at organ doses of ≥60 Gy. Thyroid cancer was the only exception, with evidence of a downturn after 20 Gy. Generally the excess relative risk per Gray, taking account of age and sex, was 5 to 10 times lower than the risk from acute exposures of <2 Gy among the Japanese atomic bomb survivors. However, the magnitude of the reduction in risk varied according to the second cancer. The results of our review provide insights into radiation carcinogenesis from fractionated high-dose exposures and are generally consistent with current theoretical models. The results can be used to refine the development of second solid cancer risk projection models for novel radiation therapy techniques.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Combinations of Radiation Therapy and Immunotherapy for Melanoma: A Review of Clinical Outcomes

Radiation therapy has long played a role in the management of melanoma. Recent advances have also demonstrated the efficacy of immunotherapy in the treatment of melanoma. Preclinical data suggest a biologic interaction between radiation therapy and immunotherapy. Several clinical studies corroborate these findings. This review will summarize the outcomes of studies reporting on patients with melanoma treated with a combination of radiation therapy and immunotherapy. Vaccine therapies often use irradiated melanoma cells, and may be enhanced by radiation therapy. The cytokines interferon-α and interleukin-2 have been combined with radiation therapy in several small studies, with some evidence suggesting increased toxicity and/or efficacy. Ipilimumab, a monoclonal antibody which blocks cytotoxic T-lymphocyte antigen-4, has been combined with radiation therapy in several notable case studies and series. Finally, pilot studies of adoptive cell transfer have suggested that radiation therapy may improve the efficacy of treatment. The review will demonstrate that the combination of radiation therapy and immunotherapy has been reported in several notable case studies, series and clinical trials. These clinical results suggest interaction and the need for further study.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Role of the Technical Aspects of Hypofractionated Radiation Therapy Treatment of Prostate Cancer: A Review

The increasing use of moderate (<35 fractions) and extreme (<5 fractions) hypofractionated radiation therapy in prostate cancer is yielding favorable results, both in terms of maintained biochemical response and toxicity. Several hypofractionation (HF) schemes for the treatment of prostate cancer are available, although there is considerable variability in the techniques used to manage intra-/interfraction motion and deliver radiation doses. We performed a review of the published studies on HF regimens as a topic of interest for the Stereotactic Ablative Radiotherapy working group, which is part of the Italian Association of Medical Physics. Aspects of organ motion management (imaging for contouring, target volume definition, and rectum/bladder preparation) and treatment delivery (prostate localization, image guided radiation therapy strategy and frequency) were evaluated and categorized to assess outcome relative to disease control and toxicity. Despite the heterogeneity of the data, some interesting trends that emerged from the review might be useful in identifying an optimum HF strategy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Is Pilocarpine Effective in Preventing Radiation-Induced Xerostomia? A Systematic Review and Meta-analysis

Purpose: To evaluate the efficacy of concomitant administration of pilocarpine on radiation-induced xerostomia in patients with head and neck cancers. Methods and Materials: The PubMed, Web of Science, Cochrane Library, and ClinicalTrials were searched to identify randomized, controlled trials studying the effect of concomitant administration of pilocarpine for radiation-induced xerostomia. Included trials were systematically reviewed, and quantifiable outcomes were pooled for meta-analysis. Outcomes of interest included salivary flow, clinician-rated xerostomia grade, patient-reported xerostomia scoring, quality of life, and adverse effects. Results: Six prospective, randomized, controlled trials in 8 articles were included in this systematic review. The total number of patients was 369 in the pilocarpine group and 367 in the control group. Concomitant administration of pilocarpine during radiation could increase the unstimulated salivary flow rate in a period of 3 to 6 months after treatment, and also reduce the clinician-rated xerostomia grade. Patient-reported xerostomia was not significantly impacted by pilocarpine in the initial 3 months but was superior at 6 months. No significant difference of stimulated salivary flow rate could be confirmed between the 2 arms. Adverse effects of pilocarpine were mild and tolerable. Conclusions: The concomitant administration of pilocarpine during radiation increases unstimulated salivary flow rate and reduces clinician-rated xerostomia grade after radiation. It also relieves patients' xerostomia at 6 months and possibly at 12 months. However, pilocarpine has no effect on stimulated salivary flow rate.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Role of Internal Mammary Node Radiation as a Part of Modern Breast Cancer Radiation Therapy: A Systematic Review

Purpose: Despite data from multiple randomized trials, the role of internal mammary lymph node irradiation as a part of regional nodal irradiation (IMLN RT–RNI) remains unanswered. Recent noteworthy data and modern RT techniques might identify a subset of patients who will benefit from IMLN RT–RNI, lending insight into the balance between improved outcomes and acceptable toxicity. We evaluated the current role of IMLN RT–RNI by analyzing randomized, prospective, and retrospective data. Methods and Materials: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a review of the published data was performed using PubMed to evaluate published studies from 1994 to 2015. The information evaluated included the number of patients, follow-up period, technical aspects of RT, and outcomes (clinical outcomes, complications/toxicity). Results: We included 16 studies (4 randomized, 4 nonrandomized, 7 retrospective, and 1 meta-analysis). Although older randomized trials failed to show differences in clinical outcomes or toxicity with IMLN RT–RNI, recent randomized data suggest the potential for improved outcomes, including overall survival, with IMLN RT–RNI. Furthermore, nonrandomized data have suggested a potential benefit for central tumors with IMLN RT–RNI. Although recent data have suggested a potential increase in pulmonary complications with IMLN RT–RNI with the use of advanced radiation techniques, toxicity rates remain low with limited cardiac toxicity data available. Conclusions: Increasing data from recent randomized trials support the use of IMLN RT–RNI. IMLN RT can be considered based on the inclusion of IMLN RT as a part of RNI in recent trials and the inclusion criteria from IMLN RT–RNI trials and for patients with central or medial tumors and axillary disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Current Status of Targeted Radioprotection and Radiation Injury Mitigation and Treatment Agents: A Critical Review of the Literature

As more cancer patients survive their disease, concerns about radiation therapy–induced side effects have increased. The concept of radioprotection and radiation injury mitigation and treatment offers the possibility to enhance the therapeutic ratio of radiation therapy by limiting radiation therapy–induced normal tissue injury without compromising its antitumor effect. Advances in the understanding of the underlying mechanisms of radiation toxicity have stimulated radiation oncologists to target these pathways across different organ systems. These generalized radiation injury mechanisms include production of free radicals such as superoxides, activation of inflammatory pathways, and vascular endothelial dysfunction leading to tissue hypoxia. There is a significant body of literature evaluating the effectiveness of various treatments in preventing, mitigating, or treating radiation-induced normal tissue injury. Whereas some reviews have focused on a specific disease site or agent, this critical review focuses on a mechanistic classification of activity and assesses multiple agents across different disease sites. The classification of agents used herein further offers a useful framework to organize the multitude of treatments that have been studied. Many commonly available treatments have demonstrated benefit in prevention, mitigation, and/or treatment of radiation toxicity and warrant further investigation. These drug-based approaches to radioprotection and radiation injury mitigation and treatment represent an important method of making radiation therapy safer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Treatment-Related Toxicity in Patients With Early-Stage Non-Small Cell Lung Cancer and Coexisting Interstitial Lung Disease: A Systematic Review

Purpose: Definitive treatment for patients with early-stage non-small cell lung cancer (ES-NSCLC) is usually well tolerated. Patients with ES-NSCLC and coexisting interstitial lung disease (ILD) are at increased risk of severe treatment-related toxicity after definitive therapy. The main objective of this systematic review is to provide a pooled estimation of treatment-related mortality and ILD-specific toxicity in this population of patients and to identify trends for further study. Methods and Materials: The MEDLINE and Embase databases were queried from respective dates of inception to January 2016. Studies that included patients who underwent definitive treatment for ES-NSCLC not combined with other treatments were included. Patients with oligometastases who were treated with aggressive palliation were included if it did not constitute the majority of patients in a specific study. The results were summarized with weighted proportions according to the sample size of individual studies. Results: Overall, 3056 records were reviewed and 50 journal articles were included in the abstraction. The weighted proportion of treatment-related mortality (and ILD-specific toxicity) in primarily medically inoperable patients was as follows: stereotactic ablative radiation therapy (SABR) 15.6% (25%), particle beam therapy 4.3% (18.2%) and radiofrequency ablation (RFA) 8.7% (25%). The data for medically operable patients who underwent surgery were extracted for reference. Treatment-related mortality and ILD-specific toxicity were 2.2% and 12%, respectively, in the surgical population. On analysis of reported SABR dose parameters, V20 ≤ 6.5% and mean lung dose ≤4.5 Gy were found to be metrics associated with reduced mortality. Conclusion: A consistently high level of treatment-related mortality and ILD-specific toxicity was observed in primarily medically inoperable patients treated with SABR, particle beam therapy, and RFA. For these patients, curative treatment should be considered in the context of the high toxicity rates and overall poor prognosis. Stringent radiation dosimetric parameters may result in reduced toxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Repeatability and Reproducibility of Radiomic Features: A Systematic Review

An ever-growing number of predictive models used to inform clinical decision making have included quantitative, computer-extracted imaging biomarkers, or “radiomic features.” Broadly generalizable validity of radiomics-assisted models may be impeded by concerns about reproducibility. We offer a qualitative synthesis of 41 studies that specifically investigated the repeatability and reproducibility of radiomic features, derived from a systematic review of published peer-reviewed literature.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

A Review of Cardiac Radioablation (CR) for Arrhythmias: Procedures, Technology, and Future Opportunities

Cardiac radioablation (CR), a new treatment for cardiac arrhythmias such as ventricular tachycardia and atrial fibrillation, has had promising clinical outcomes to date. There is consequent desire for rapid clinical adoption. However, CR presents unique challenges to radiation therapy, and it is paramount that clinical adoption be performed safely and effectively. Recent reviews comprehensively detail patient selection, clinical history, treatment outcomes, and treatment toxicities but only briefly mention the technical aspects of CR. To address this knowledge gap, this review collates currently available knowledge regarding CR technology choice and procedural details to help inform and guide clinics considering implementing their own CR program, to aid technique standardization, and to highlight areas that require further development or verification.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Effects of Exercise During Radiation Therapy on Physical Function and Treatment-Related Side Effects in Men With Prostate Cancer: A Systematic Review and Meta-Analysis

Radiation therapy is a commonly used treatment for prostate cancer; however, the side effects may negatively affect quality of life and cause patients to be less physically active. Although exercise has been shown to mitigate radiation therapy–related fatigue in men with prostate cancer during radiation therapy, other adverse effects of treatment such as physical deconditioning, urinary symptoms, or sexual dysfunction have not been systematically reviewed in this patient population. Thus, the purpose of this review was to investigate the effect of exercise on physical function and treatment-related side effects in men with prostate cancer undergoing radiation therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Distress Among Locally Advanced Breast Cancer Patients from Diagnosis to Follow-Up: A Critical Review of Literature

This critical review used a systematic approach to explore the prevalence of distress among locally advanced breast cancer (LABC) patients along their treatment journey. This review explored the domains of distress (psychosocial, physical and/or practical) that are significant to this patient population and determined indications for psychosocial support throughout the patients' treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Recent advances in MoS{sub 2} nanostructured materials for energy and environmental applications – A review

Molybdenum disulfide (MoS{sub 2}), a layered transition metal dichalcogenide with an analogous structure to graphene, has attracted enormous attention worldwide owing to its use in a variety of applications such as energy storage, energy conversion, environmental remediation and sensors. MoS{sub 2} and graphene have almost similar functional properties such as high charge carrier transport, high wear resistance and good mechanical strength and friction. However, MoS{sub 2} is advantageous over graphene due to its low-cost, abundancy, tailorable morphologies and tuneable band gap with good visible light absorption properties. In this review, we have focussed mainly on recent advances in MoS{sub 2} nanostructured materials for the applications in the broad area of energy and environment. Special attention has been paid to their applications in dye-sensitized solar cells, supercapacitor, Li-ion battery, hydrogen evolution reaction, photocatalysis for the degradation of organic pollutants, chemical/bio sensors and gas sensors. Finally, the challenges to design MoS{sub 2} nanostructures suitable for energy and environmental applications are also highlighted. - Highlights: • Applications of MoS{sub 2} nanostructures towards energy, environmental remediation and sensors were summarized. • Recent advances in the development of MoS{sub 2} nanostructured materials were systematically investigated. • Wide range of energy applications including DSSCs, supercapacitors, Li-ion batteries and HER were reviewed. • Key challenges and optimization of structure for superior performance associated with MoS{sub 2} nanostructures were discussed. • Advances of environmental remediation based on MoS{sub 2} nanostructures were significantly highlighted.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗