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At least 757 records · Page 42

Radiofrequency and Microwave Ablation Compared to Systemic Chemotherapy and to Partial Hepatectomy in the Treatment of Colorectal Liver Metastases: A Systematic Review and Meta-Analysis

PurposeTo assess safety and outcome of radiofrequency ablation (RFA) and microwave ablation (MWA) as compared to systemic chemotherapy and partial hepatectomy (PH) in the treatment of colorectal liver metastases (CRLM).MethodsMEDLINE, Embase and the Cochrane Library were searched. Randomized trials and comparative observational studies with multivariate analysis and/or matching were included. Guidelines from National Guideline Clearinghouse and Guidelines International Network were assessed using the AGREE II instrument.ResultsThe search revealed 3530 records; 328 were selected for full-text review; 48 were included: 8 systematic reviews, 2 randomized studies, 26 comparative observational studies, 2 guideline-articles and 10 case series; in addition 13 guidelines were evaluated. Literature to assess the effectiveness of ablation was limited. RFA + systemic chemotherapy was superior to chemotherapy alone. PH was superior to RFA alone but not to RFA + PH or to MWA. Compared to PH, RFA showed fewer complications, MWA did not. Outcomes were subject to residual confounding since ablation was only employed for unresectable disease.ConclusionThe results from the EORTC-CLOCC trial, the comparable survival for ablation + PH versus PH alone, the potential to induce long-term disease control and the low complication rate argue in favour of ablation over chemotherapy alone. Further randomized comparisons of ablation to current-day chemotherapy alone should therefore be considered unethical. Hence, the highest achievable level of evidence for unresectable CRLM seems reached. The apparent selection bias from previous studies and the superior safety profile mandate the setup of randomized controlled trials comparing ablation to surgery.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Post-Biopsy Manoeuvres to Reduce Pneumothorax Incidence in CT-Guided Transthoracic Lung Biopsies: A Systematic Review and Meta-analysis

This systematic review and meta-analysis investigated post-biopsy manoeuvres to reduce pneumothorax following computed tomography-guided percutaneous transthoracic lung biopsy. Twenty-one articles were included with 7080 patients. Chest drain insertion rates were significantly reduced by ninefold with the normal saline tract sealant compared to controls (OR 0.11, 95% CI 0.02–0.48), threefold with the rapid rollover manoeuvre to puncture site down (OR 0.34, 95% CI 0.18–0.63), threefold with the tract plug (OR 0.33, 95% CI 0.22–0.48) and threefold with the blood patch (OR 0.39, 95% CI 0.26–0.58). The absolute chest drain insertion rates were the lowest in the normal saline tract sealant (0.8% vs 7.3% for controls), rapid rollover (1.9% vs 5.2%), deep expiration and breath-hold on needle extraction (0.9% vs 1.8%) and standard rollover versus no rollover (2.6% vs 5.2%). These findings highlight post-biopsy manoeuvres which could help reduce pneumothorax and chest drain insertions following lung biopsies. Level of Evidence: Level 1/no level of evidence, systematic review.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Biological Recycling of Polyethylene Terephthalate: A Mini-Review

Plastics have become an inseparable part of our life in the society due to their merits such as low cost, light weight, good mechanical and thermal properties along with easy process ability. Since the last few decades, the unrestrained use of plastics in various fields like agriculture, packaging, transportation has raised a serious issue about its disposal and pollution. An efficient decomposition of plastics takes about 1000 years. Not only there is an increase in the problem of waste disposal of plastics but also they release CO{sub 2} and dioxins on burning which contributes to cause pollution. There is a growing concern for use of efficient microorganisms meant for biodegradation of non-degradable synthetic polymer because conventionally used methods for plastic disposal are ineffective for plastic waste management. This review paper focuses on one such type of plastic-polyethylene terephthalate (PET) which is widely used in a flexible packaging application, its manufacturing process and the various effects of waste generated by it on the surrounding environment. This review discusses an overview of various existing plastic disposal methods along with their limitations and mechanism of biodegradation of PET and factors affecting biodegradation.

54 ENVIRONMENTAL SCIENCES↗

Viscosity of Heterogeneous Silicate Melts: A Review

The viscosity of solid phase containing heterogeneous silicate melts is discussed in this review. The crucial parameters characterizing silicate melt structure are first presented, i.e., volume fraction of solid particles, particle shape and size. The measurement and calculation methods of these parameters are summarized and the influence of the parameters on viscosity is discussed. Next, a theoretical description of rheological behavior in heterogeneous silicate melts is given, focusing on non-Newtonian characteristics, e.g., shear-dependence, time-dependence, and yield stress. The viscosity models which were proposed in the last half century are reviewed and critically assessed. This paper concludes with opportunities and suggestions for future work.

36 MATERIALS SCIENCE↗

Review of cardiovascular imaging in the journal of nuclear cardiology in 2016: Part 2 of 2—myocardial perfusion imaging

In 2016, the Journal of Nuclear Cardiology published many high-quality articles. Similar to previous years, we will summarize here a selection of the articles that were published in the Journal in 2016 to provide a concise review of the main advancements that have recently occurred in the field. In the first article of this two-part series we focused on publications dealing with positron emission tomography, computed tomography, and magnetic resonance. This review will place emphasis on myocardial perfusion imaging using single-photon emission-computed tomography summarizing advances in the field including in diagnosis, prognosis, and appropriate use.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Guidelines in review: Comparison of ESC and AHA guidance for the diagnosis and management of infective endocarditis in adults

Over recent years, new evidence has led a rethinking of the available guidance on the diagnosis and management of infective endocarditis (IE). This review compares the most recently available guidance provided by the American Heart Association (AHA) IE Writing Committee, and the Task Force for the management of IE of the European Society of Cardiology (ESC). This represents the sixth of a new series of comparative guidelines review published in the Journal.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

A Review of Experimental Animal Radon Health Effects [Book Chapter]

Abundant epidemiological data from underground miners confirm that radon decay products (progeny) are carcinogenic, although the evidence is less conclusive on the quantitative risks of these exposures, especially for indoor air. The imprecision results principally from differences between exposures in mining and domestic environments and from uncertainties about the interaction between smoking and exposure to radon progeny. Experimental animal studies of radon-induced lung cancer are particularly valuable for understanding the carcinogenicity of human radon exposures in the home and in the workplace. Animals can be exposed to a variety of agents under carefully controlled conditions and then sacrificed for the study of developing lesions or held for their life span for tumor development. The doses to critical cells in the respiratory tract can be determined, and these in turn can be related to doses to critical cells in the respiratory tract of humans exposed to similar aerosols. The study of radon-induced mutations and changes in expression of oncogenes and tumor-suppressor genes as well as growth factors and growth factor receptors during tumor progression in animals also provides valuable evidence on the underlying mechanisms of radon carcinogenesis. This evidence, particularly that of the efficiency for oncogenic transformation at low dose rates, is crucial to the determination of the risk of lung cancer from exposure to indoor levels of radon. This review of animal health effects data emphasizes the carcinogenicity of radon exposures in rats; mechanistic data on radon-induced lung tumors in rats are currently sparse and are not reviewed here.

560162* -- Radionuclide Effects, Kinetics, & Toxic↗

Automated Extraction of Energy Systems Information from Remotely Sensed Data: A Review and Analysis

We report high quality energy systems information is a crucial input to energy systems research, modeling, and decision-making. Unfortunately, actionable information about energy systems is often of limited availability, incomplete, or only accessible for a substantial fee or through a non-disclosure agreement. Recently, remotely sensed data (e.g., satellite imagery, aerial photography) have emerged as a potentially rich source of energy systems information. However, the use of these data is frequently challenged by its sheer volume and complexity, precluding manual analysis. Recent breakthroughs in machine learning have enabled automated and rapid extraction of useful information from remotely sensed data, facilitating large-scale acquisition of critical energy system variables. Here we present a systematic review of the literature on this emerging topic, providing an in-depth survey and review of papers published within the past two decades. We first taxonomize the existing literature into ten major areas, spanning the energy value chain. Within each research area, we distill and critically discuss major features that are relevant to energy researchers, including, for example, key challenges regarding the accessibility and reliability of the methods. We then synthesize our findings to identify limitations and trends in the literature as a whole, and discuss opportunities for innovation. These include the opportunity to extend the methods beyond electricity to broader energy systems and wider geographic areas; and the ability to expand the use of these methods in research and decision making as satellite data become cheaper and easier to access. We also find that there are persistent challenges: limited standardization and rigor of performance assessments; limited sharing of code, which would improve replicability; and a limited consideration of the ethics and privacy of data.

97 MATHEMATICS AND COMPUTING↗

Corrosion resistance of steel fibre reinforced concrete - A literature review

Steel fibre reinforced concrete (SFRC) is increasingly being used in the construction of civil infrastructure. However, there are inconsistencies among international standards and guidelines regarding the consideration of carbon-steel fibres for the structural verification of SFRC exposed to corrosive environments. This paper presents a review of the published research regarding carbonation- and chloride-induced corrosion of SFRC, and proposes a deterioration theory for cracked SFRC exposed to chlorides and carbonation, based on the damage at the fibre-matrix interface. The review confirms an overall agreement among academics and regulators regarding the durability of uncracked SFRC exposed to chlorides and carbonation. Contrariwise, the durability of cracked SFRC is under discussion at the technical and scientific level, as there is a large dispersion on the experimental results and some of the mechanisms governing the corrosion of carbon-steel fibres in cracks and its effects on the fracture behaviour of SFRC are not fully understood.

36 MATERIALS SCIENCE↗

Effect of Permeability Heterogeneity on Area of Review

The Area of Review is one of the most important aspects of a geologic CO 2 storage site permit application and regulatory requirement. The US Environmental Protection Agency (EPA) has implemented an Area of Review (AoR) requirement for Class VI CO 2 injection wells for geologic sequestration. Reservoir permeability is one of the most important parameters controlling AoR evolution but is generally highly heterogeneous and difficult to constrain. We have used a numerical model for Rock Springs Uplift in Wyoming as an example site to characterize how the heterogeneity in reservoir permeability affects AoR. We have performed multiple reservoir simulations using multiple, equally-likely realizations of heterogeneous permeability. We considered multiple CO 2 injection scenarios with varying injection rates as well as varying injection and post-site durations. Results of our study demonstrate that uncertainty in permeability heterogeneity can significantly influence AoR for both CO 2 saturation and pressure. In our example, the CO 2 AoR varied by as much as 2-3 times while the pressure AoR varied over 1.5 – 2 times. Lastly, such type of variability can have significant implications in defining AoR for site permit applications.

58 GEOSCIENCES↗

Assessing Internet energy intensity: A review of methods and results

Assessing the average energy intensity of Internet transmissions is a complex task that has been a controversial subject of discussion. Estimates published over the last decade diverge by up to four orders of magnitude — from 0.0064 kilowatt-hours per gigabyte (kWh/GB) to 136 kWh/GB. This article presents a review of the methodological approaches used so far in such assessments: i) top–down analyses based on estimates of the overall Internet energy consumption and the overall Internet traffic, whereby average energy intensity is calculated by dividing energy by traffic for a given period of time, ii) model-based approaches that model all components needed to sustain an amount of Internet traffic, and iii) bottom–up approaches based on case studies and generalization of the results. Our analysis of the existing studies shows that the large spread of results is mainly caused by two factors: a) the year of reference of the analysis, which has significant influence due to efficiency gains in electronic equipment, and b) whether end devices such as personal computers or servers are included within the system boundary or not. For an overall assessment of the energy needed to perform a specific task involving the Internet, it is necessary to account for the types of end devices needed for the task, while the energy needed for data transmission can be added based on a generic estimate of Internet energy intensity for a given year. Separating the Internet as a data transmission system from the end devices leads to more accurate models and to results that are more informative for decision makers, because end devices and the networking equipment of the Internet usually belong to different spheres of control. -- Highlights: • Assessments of the energy intensity of the Internet differ by a factor of 20,000. • We review top–down, model-based, and bottom–up estimates from literature. • Main divergence factors are the year studied and the inclusion of end devices. • We argue against extending the Internet system boundary beyond data transmission. • Decision-makers need data that differentiates between end devices and transmission.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

A critical review of principal traffic noise models: Strategies and implications

The paper presents an exhaustive comparison of principal traffic noise models adopted in recent years in developed nations. The comparison is drawn on the basis of technical attributes including source modelling and sound propagation algorithms. Although the characterization of source in terms of rolling and propulsion noise in conjunction with advanced numerical methods for sound propagation has significantly reduced the uncertainty in traffic noise predictions, the approach followed is quite complex and requires specialized mathematical skills for predictions which is sometimes quite cumbersome for town planners. Also, it is sometimes difficult to follow the best approach when a variety of solutions have been proposed. This paper critically reviews all these aspects pertaining to the recent models developed and adapted in some countries and also discusses the strategies followed and implications of these models. - Highlights: • Principal traffic noise models developed are reviewed. • Sound propagation algorithms used in traffic noise models are compared. • Implications of models are discussed.

54 ENVIRONMENTAL SCIENCES↗

Human–environment interactions in urban green spaces — A systematic review of contemporary issues and prospects for future research

Scientific papers on landscape planning underline the importance of maintaining and developing green spaces because of their multiple environmental and social benefits for city residents. However, a general understanding of contemporary human–environment interaction issues in urban green space is still incomplete and lacks orientation for urban planners. This review examines 219 publications to (1) provide an overview of the current state of research on the relationship between humans and urban green space, (2) group the different research approaches by identifying the main research areas, methods, and target groups, and (3) highlight important future prospects in urban green space research. - Highlights: • Reviewed literature on urban green pins down a dearth of comparative studies. • Case studies in Africa and Russia are marginalized – the Europe and US dominate. • Questionnaires are used as major tool followed by GIS and quantitative approaches. • Developing countries should contribute in building an urban green space agenda. • Interdisciplinary, adaptable and pluralistic approaches can satiate a knowledge gap.

54 ENVIRONMENTAL SCIENCES↗

A review of EIAs on trade policy in China: Exploring the way for economic policy EIAs

During the discussion on the “Environmental Protection Law Amendment (draft)” in 2011, it was decided to drop the proposed clauses related to environmental impact assessments (EIAs) on policy, which means that there remained no provisions for policy EIAs, and China's strategic environmental assessment system stayed limited to the planning level. However, considering that economic policy making is causing significant direct and indirect environmental problems and that almost every aspect of governmental policy has an economic aspect, EIAs on economic policies are of the utmost urgency. The purpose of this study is to review the EIA work that has been carried out on trade policy in China through four case studies, and illustrate how trade policy EIAs can be helpful in achieving better environmental outcomes in the area of trade. Through the trade policy EIA case studies we try to argue for the feasibility of conducting EIAs on economic policies in China. We also discuss the implications of the case studies from the point of view of how to proceed with EIAs on economic policy and how to promote their practice. - Highlights: • SEA system is incomplete and stays limited to the plan EIA level in China. • EIA on economic policy is of utmost importance for all the developing countries. • Four case studies of trade policy EIA in China are reviewed for policy implications. • Departmental competition for political power impedes economic policy EIAs in China. • Legislative regulation on policy EIA is the first thing needed to overcome barrier.

54 ENVIRONMENTAL SCIENCES↗

Temporal discounting in life cycle assessment: A critical review and theoretical framework

Temporal homogeneity of inventory data is one of the major problems in life cycle assessment (LCA). Addressing temporal homogeneity of life cycle inventory data is important in reducing the uncertainties and improving the reliability of LCA results. This paper attempts to present a critical review and discussion on the fundamental issues of temporal homogeneity in conventional LCA and propose a theoretical framework for temporal discounting in LCA. Theoretical perspectives for temporal discounting in life cycle inventory analysis are discussed first based on the key elements of a scientific mechanism for temporal discounting. Then generic procedures for performing temporal discounting in LCA is derived and proposed based on the nature of the LCA method and the identified key elements of a scientific temporal discounting method. A five-step framework is proposed and reported in details based on the technical methods and procedures needed to perform a temporal discounting in life cycle inventory analysis. Challenges and possible solutions are also identified and discussed for the technical procedure and scientific accomplishment of each step within the framework. - Highlights: • A critical review for temporal homogeneity problem of life cycle inventory data • A theoretical framework for performing temporal discounting on inventory data • Methods provided to accomplish each step of the temporal discounting framework.

54 ENVIRONMENTAL SCIENCES↗

Community participation in Health Impact Assessment. A scoping review of the literature

Currently, the engagement of local communities in Health Impact Assessment is becoming more and more important. A scoping review was performed to take stock of visions, methods and experiences in this field. A combined Scopus and Medline search yielded 100 articles in scientific journals. The final selection consisted of 43 papers, including case studies, evaluation studies, reviews, and opinion papers. After analysis, consultation of four experts was performed to check preliminary study outcomes. A grey literature web search was performed to check and complement the results. Results show that community participation is generally considered a core element in HIA. Views as expressed in the papers concern, firstly, the need for and value of local knowledge, secondly, the adherence to or application of democratic values and, thirdly, empowerment of communities. Three categories of methods are used in relation to community participation, often in combination: methods to facilitate knowledge elicitation, to ensure the inclusion of communities in the HIA process, and to build community capacity to participate in policy development. However, the theoretical or practical underpinning of the choice for specific methods is mostly not presented. The experiences described in the papers mainly focus on the access to local knowledge and its usability as a source of evidence in the HIA process. Described effects of community participation are (improved) relations between communities and local agencies, policy makers and professionals and the empowerment of community members. Although these effects are ascribed to community participation, many papers do not provide support for this conclusion beyond the retrospective perception of participants. Expert consultation and additional analysis of the grey literature supported the results derived from the scientific literature and provided more in-depth knowledge. In the grey literature theoretical frameworks, methods and tools for community participation in HIA were more extensively reported as compared to the scientific literature. We conclude that the visions, methods and experiences concerning community participation show that a participative approach may contribute to better, context specific knowledge. It appears that participative HIA has health promotion potential as it helps develop responsive policies. To accomplish this, HIA should, firstly, be better embedded in broader health promotion programmes. Secondly, the methods and approaches for community participation applied in HIA should be theory-informed and well described. The grey literature offers entry points. Finally, more robust and systematic evaluation and research is needed to assess the impact of HIAs on communities and policies.

54 ENVIRONMENTAL SCIENCES↗

Resilient cooling strategies – A critical review and qualitative assessment

The global effects of climate change will increase the frequency and intensity of extreme events such as heatwaves and power outages, which have consequences for buildings and their cooling systems. Buildings and their cooling systems should be designed and operated to be resilient under such events to protect occupants from potentially dangerous indoor thermal conditions. This study performed a critical review on the state-of-the-art of cooling strategies, with special attention to their performance under heatwaves and power outages. We proposed a definition of resilient cooling and described four criteria for resilience—absorptive capacity, adaptive capacity, restorative capacity, and recovery speed —and used them to qualitatively evaluate the resilience of each strategy. The literature review and qualitative analyses show that to attain resilient cooling, the four resilience criteria should be considered in the design phase of a building or during the planning of retrofits. The building and relevant cooling system characteristics should be considered simultaneously to withstand extreme events. A combination of strategies with different resilience capacities, such as a passive envelope strategy coupled with a low-energy space-cooling solution, may be needed to obtain resilient cooling. Finally, a further direction for a quantitative assessment approach has been pointed out.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Systematic review of biological effects of exposure to static electric fields. Part II: Invertebrates and plants

Highlights: • Environmental impacts of static EF were assessed in invertebrate and plant studies. • Invertebrates are able to perceive the presence of static EF near HVDC power lines. • No evidence for adverse effects on physiological functions at HVDC field levels. • Corona-action appears to cause adverse biological effects at very high field levels. • Methodological flaws in all reviewed studies lowered credibility in the results. The construction of high-voltage direct current (HVDC) lines for the long-distance transport of energy is becoming increasingly popular. This has raised public concern about potential environmental impacts of the static electric fields (EF) produced under and near HVDC power lines. As the second part of a comprehensive literature analysis, the aim of this systematic review was to assess the effects of static EF exposure on biological functions in invertebrates and plants and to provide the basis for an environmental impact assessment of such exposures.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗