bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of Laser‐Generated Ion Beams
Authors: Steinke S. , Schnürer M. , Sokollik T. , Andreev A.A. , Nickles P.V. , Henig A. , Hörlein R. , Kiefer D. , Jung D. , Schreiber J. , Tajima T. , Hegelich M. , Habs D. , Sandner W. 
Published: June 2011

AbstractIn this paper the route towards the current optimum of laser generated ion beams by subsequently changing the important parameters such as target thickness, laser pulse contrast, angle of incidence and laser pulse polarization is sketched. Beginning with parameters of isothermal target normal sheath acceleration (TNSA), we reached the regime where the plasma expansion can be described adiabatically and results in a symmetric ion acceleration. Further we demonstrated a way to phase match the accelerating electron population with the ions, namely coherent acceleration of ions by laser pulses (CAIL), which finally lead to radiation pressure acceleration (RPA) if the laser polarization was changed from linear to circular. These findings of ion acceleration with transparent solid targets are additionally supported by analyzing the optical properties of the transmitted laser pulse (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Kinetics of Photon Radiation off an e–e+‐Plasma Created from the Vacuum in a Strong Laser Field
Authors: Blaschke D. B. , Röpke G. , Schmidt S. M. , Smolyansky S. A. , Tarakanov A. V. 
Published: June 2011

AbstractWe consider the one‐photon annihilation mechanism in a electron ‐ positron quasiparticle plasma (EPP) created from the vacuum in a strong subcritical laser field due to the dynamical Schwinger mechanism. On the basis of a kinetic theory approach we show that the secondary photons have a radiation spectrum proportional to 1/k (flicker noise). This effect is very small for EPP excitations in the optical spectrum but can reach quite observable values in the γ ‐ray region (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effective Generation of Collimated Ion Beams by Relativistic Laser Pulse Using 2D Microstructured Foils: 3D PIC Simulations
Authors: Sidorov I. A. , Savelev A. B. , Romanovsky M. Yu. , Bychenkov V. Yu. , Brantov A. V. , Romanov D. V. 
Published: June 2011

AbstractHigh power laser systems allow us to obtain collimated laser beams by irradiating thin foils with short intense laser pulses. In this work we performed several numerical simulations to study influence of target structure on ion beam acceleration efficiency. New target design was proposed to enhance ion acceleration mechanisms. For numerical simulations we used Mandor2 package: 3D Particle‐in‐cell code designed for analysis of interactions between short powerful laser pulses and plasma.The target proposed in the work was a disc (diameter 15 μ m, width 3 μ m) with 6 symmetrical holes in it (diameter 3 μ m). This target was irradiated by a laser pulse with the following properties: intensity 1019 W/cm2, pulse duration 200 fs, wavelength 1 μ m, focal spot size 10 μ m. For comparison similar simulations were performed for a solid target. Comparisons showed that the target with holes produced more energetic ion beams than the solid one (maximum energy 10 MeV for target with holes vs. 4 MeV for solid one). However the number of accelerated protons was 2 times lower in case of the target with holes.The mechanism of ion acceleration from such targets was also investigated in this work. It was discovered that the ion beam consists of several streams, each originating from the particular hole in the target. We assumed the following mechanism of formation of such streams: after the laser‐plasma interaction, hot electrons appear, which then flow to the hole area, creating an uncompensated negative electric charge. This charge attracts ions, which focus in the center of the hole. Focused ions are then accelerated via TNSA mechanism, forming observed streams.A possibility of ion acceleration by longitudinal components of a Gaussian laser pulse is also investigated in this work. The optimal configuration for acceleration by longitudinal fields is shown to match the optimal configuration of the proposed target (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling of Kα X‐Ray Yield From a Foil Under the Vacuum Heating of Hot Electrons by a Femtosecond Laser Pulse
Authors: Kostenko O. F. , Andreev N. E. 
Published: June 2011

AbstractEnhancement of characteristic x‐ray yield from a metal foil, coated with spherical clusters, irradiated by a p ‐polarized Gaussian femtosecond laser beam, is investigated depending on the cluster size, laser pulse intensity and the foil thickness. Simulations were carried out both for the hot electrons, accelerated in accordance with the Brunel model of vacuum heating, and for corresponding Maxwellian distribution of hot electrons. Existence of an interval of cluster sizes with respect to the laser wavelength, in which the number of emitted photons from the foil with clustered surface exceeds one from the polished foil, and increase of Kα yield with growth of the laser field angle of incidence is most pronounced, is shown (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temporal and Spectral Characteristics of the Radiation Generated by an Electron Driven by a Relativistically Intense Laser Field
Authors: Galkin A.L. , Kalashnikov M.P. , Korobkin V.V. , Romanovsky M.Yu. , Shiryaev O.B. , Trofimov V.A. 
Published: June 2011

AbstractThe electron dynamics and radiation emission in the field of a relativistically intense laser pulse is studied. The electron motions induced by a focused laser beam are described on the basis of the Newton equation with the Lorentz force. The radiation emitted by the electron comprises a set of electromagnetic pulses having durations much shorter than the optical cycle. For a femtosecond driving laser pulse with duration of several optical cycles, durations of pulses emitted by the accelerated electron belong to the zeptosecond range. The spectral width of radiation emitted by the electron depends on durations of emitted pulses. The electron emits a modulated spectrum in the case of the linearly polarized driving pulse (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
CarbFix: a CCS pilot project imitating and accelerating natural CO2 sequestration
Authors: Aradóttir Edda S.P. , Sigurdardóttir Hólmfrídur , Sigfússon Bergur , Gunnlaugsson Einar 
Published: June 2011

AbstractCarbFix, a combined industrial‐academic pilot program, was developed in order to assess the feasibility of in situ CO2 mineral sequestration in basaltic rocks. Unique to CarbFix is its connection to the Hellisheidi geothermal power plant, allowing for capture of otherwise emitted CO2 in addition to CO2 transport and mineral sequestration.Extensive research has been conducted in order to characterize physical properties of the pilot injection site in Hellisheidi. Tracer tests have been carried out and continuous well‐logging confirmed separation of the target formation from shallower groundwater systems. Alteration mineralogy in natural analogs has been mapped out in order to predict which minerals are likely to precipitate upon CO2 injection. In addition to carbonates, these include clays, zeolites, and poorly crystalline hydroxides. Some of the secondary minerals will compete with carbonates for cations dissolved from the rock matrix.Numerical modeling plays an important role in the CarbFix project as it provides tools to predict and optimize long‐term management of the injection site as well as to quantify the amount of CO2 that can be mineralized. A reactive transport model has been developed and numerical simulations of the pilot CO2 injection are ongoing. Extensive monitoring provides the basis for testing, validating, and calibrating reactive transport models.It is anticipated that the results of CarbFix will be used to optimize the in situ carbon mineralization process, enabling it in basalt and ultramafic rock formations throughout the world. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
GIS‐evaluation of two slope‐calculation methods regarding their suitability in slope analysis using high‐precision LiDAR digital elevation models
Authors: Ashraf M. Irfan , Zhao Zhengyong , Bourque Charles P.‐A. , Meng Fan‐Rui 
Published: June 2011

AbstractSlope is a metric that is essential to describe surface hydrological processes, including overland flow, soil erosion, and sediment transport. Most commercial GIS have built‐in functions to calculate the slope from Digital Elevation Models (DEMs) by means of average neighbourhood methods that are appropriate for coarse‐resolution DEMs. Emergence of high‐resolution DEMs from LiDAR data creates a need to re‐assess the suitability of existing algorithms for calculating slope in hydrological applications.In this study, we investigate the properties of two different slope‐calculation methods: an average‐neighbourhood‐slope (ANS) and a downhill‐slope (DHS) method. Conceptually, the DHS method provides a more intuitive description of surface water‐flow characteristics in an uneven terrain. DEMs of five different types were used to evaluate the methods, namely a 1‐m and 10‐m resolution DEM interpolated from irregular elevation point‐data generated with conventional photogrammetric techniques, and a 1‐m, 5‐m, and 10‐m resolution DEM derived from LiDAR data. The slopes calculated were summarized for the entire watershed, along mapped streams, and within pre‐defined ‘stream buffers’. Slopes generated for the entire watershed with 1‐m resolution LiDAR DEM indicated that the ANS method on an average produced smaller slopes than the DHS method (0·64°). A similar trend was observed in stream buffers, with greatest slope differences (ΔS) between methods within 20‐m buffers, when the 1‐m LiDAR‐based DEM was used (ΔS = 1·12°). In contrast, the ANS‐calculated slopes along mapped streams were generally larger than those calculated with the DHS method for LiDAR‐based DEMs (ΔS = 0·81°). The results from this study signal the need for caution when estimating slopes along streams from high‐accuracy, LiDAR‐generated DEMs. Copyright © 2011 John Wiley & Sons, Ltd.
Treatment strategy for early hepatocellular carcinomas: Comparison of radiofrequency ablation with or without transcatheter arterial chemoembolization and surgical resection
Authors: Tashiro Hirotaka , Aikata Hiroshi , Waki Koji , Amano Hironobu , Oshita Akihiko , Kobayashi Tsuyoshi , Tanimoto Yoshisato , Kuroda Shintaro , Tazawa Hirofumi , Chayama Kazuaki , Asahara Toshimasa , Ohdan Hideki 
Published: June 2011

AbstractBackgroundThe preferred choice between surgical treatment and radiofrequency ablation (RFA) for the treatment of small resectable hepatocelluar carcinoma (HCC) has become a subject for debate.MethodsWe compared the results of hepatic resection (n = 199) with those of RFA (n = 87), of which 69 patients were treated with transcatheter arterial chemoembolization followed by RFA, for 286 patients with 3 or fewer nodules, none of which exceeded 3 cm in diameter at Hiroshima University Hospital.ResultsIn subgroup analysis of single HCC with tumor size exceeding 2 cm in Child‐Pugh class A, the disease‐free survival time was significantly longer in the surgical resection group than in the RFA group (P = 0.048). In the subgroups of a single and multiple HCC with tumor size ≤2 cm in Child‐Pugh class A, the overall and disease‐free survival rates were almost the same for the surgical resection and RFA groups (P = 0.46 and 0.58, respectively, in single HCC, and P = 0.98 and 0.98, respectively, in multiple HCC).ConclusionSurgical resection may provide better long‐term disease‐free survival than RFA in the subgroup of a single HCC exceeding 2 cm of Child‐Pugh class A. J. Surg. Oncol. 2011;104:3–9. © 2011 Wiley‐Liss, Inc.
Paroxysmal dyskinesias
Authors: Bhatia Kailash P. 
Published: June 2011

AbstractParoxysmal movement disorders are a relatively rare and heterogenous group of conditions manifesting as episodic dyskinesia lasting a brief duration. Three forms are clearly recognized, namely, paroxysmal kinesigenic (PKD), nonkinisegenic (PNKD), and exercise induced (PED). There have been major advances in the understanding of the pathophysiological mechanisms and the genetics of these disorders, leading to better clinical definitions based on genotype–phenotype correlations in the familial idiopathic forms. PKD is genetically heterogenous, but there is linkage to chromosome 16 in a number of families. PNKD is due to mutations of theMR‐1gene. PED is genetically heterogenous, but a number of familial and sporadic cases may be due toGLUT‐1gene mutations. TheGLUT1gene–related form of PED may respond to a ketogenic diet. Potassium and calcium channel mutations underlie the 2 main forms of episodic ataxia (EA1 and EA2), whereas benign torticollis of infancy may also be a calcium channel disorder. © 2011MovementDisorder Society
The use of medications with anticholinergic properties and risk factors for their use in hospitalised elderly patients
Authors: Wawruch Martin , Macugova Agata , Kostkova Lenka , Luha Jan , Dukat Andrej , Murin Jan , Drobna Veronika , Wilton Lynda , Kuzelova Magdalena 
Published: June 2011

ABSTRACTPurposeThe aims of the present study were to evaluate the use of drugs with anticholinergic properties in elderly patients and to identify risk factors that increase the patient's chance of being given such medications.MethodsThe study was performed on a sample of 1636 patients aged ≥65 years hospitalised during the period between 1 January 2008 and 31 December 2009 in three municipal hospitals. To evaluate the factors influencing the use of anticholinergic medications, we compared two groups—users and non‐users of such drugs—in terms of sociodemographic and clinical characteristics as well as comorbid conditions. The most important risk factors were identified using the binary logistic regression model.ResultsHospitalisation led to a significant increase in the prevalence of anticholinergic medication users, when comparing their occurrence at the time of hospital admission and discharge (10.5% and 14.2%, respectively; p < 0.001). A significantly higher total number of prescribed drugs were found in the group of users compared with non‐users, at both hospital admission (7.2 ± 3.5 vs 5.7 ± 3.1; p < 0.001) and discharge (8.7 ± 3.1 vs 7.5 ± 2.9; p < 0.001). Immobilisation, urinary incontinence and retention, constipation, gastroduodenal ulcer disease as well as neurologic and psychiatric comorbidities (depression, Parkinson's disease, epilepsy) appeared as the most important risk factors of using anticholinergic medications.ConclusionsPhysicians should be aware of the greater risk of adverse anticholinergic effects of drugs in certain therapeutic classes in the elderly. In patients with risk factors mentioned previously, special attention should be paid to active identification of anticholinergic effects of medications. Copyright © 2011 John Wiley & Sons, Ltd.
Framework for integrating sustainability into remediation projects
Authors: Holland Karin S. , Lewis Raymond E. , Tipton Karina , Karnis Stella , Dona Carol , Petrovskis Erik , Bull Louis P. , Taege Deborah , Hook Christopher 
Published: June 2011

AbstractThe US Sustainable Remediation Forum (SURF) created this Framework to enable sustainability parameters to be integrated and balanced throughout the remediation project life cycle, while ensuring long‐term protection of human health and the environment and achieving public and regulatory acceptance. Parameters are considerations, impacts, or stressors of environmental, social, and economic importance. Because remediation project phases are not stand‐alone entities but interconnected components of the wider remediation system, the Framework provides a systematic, process‐based approach in which sustainability is integrated holistically and iteratively within the wider remediation system. By focusing stakeholders on the preferred end use or future use of a site at the beginning of a remediation project, the Framework helps stakeholders form a disciplined planning strategy. Specifically, the Framework is designed to help remediation practitioners (1) perform a tiered sustainability evaluation, (2) update the conceptual site model based on the results of the sustainability evaluation, (3) identify and implement sustainability impact measures, and (4) balance sustainability and other considerations during the remediation decision‐making process. The result is a process that encourages communication among different stakeholders and allows remediation practitioners to achieve regulatory goals and maximize the integration of sustainability parameters during the remediation process. © 2011 Wiley Periodicals, Inc.
Guidance for performing footprint analyses and life‐cycle assessments for the remediation industry
Authors: Favara Paul J. , Krieger Todd M. , Boughton Bob , Fisher Angela S. , Bhargava Mohit 
Published: June 2011

AbstractThe US Sustainable Remediation Forum (SURF) proposes a nine‐step process for conducting and documenting a footprint analysis and life‐cycle assessment (LCA) for remediation projects. This guidance is designed to assist remediation practitioners in evaluating the impacts resulting from potential remediation activities so that preventable impacts can be mitigated. Each of the nine steps is flexible and scalable to a full range of remediation projects and to the tools used by remediation practitioners for quantifying environmental metrics. Two fictional case studies are presented to demonstrate how the guidance can be implemented for a range of evaluations and tools. Case‐study findings show that greater insight into a study is achieved when the nine steps are followed and additional opportunities are provided to minimize remediation project footprints and create improved sustainable remediation solutions. This guidance promotes a consistent and repeatable process in which all pertinent information is provided in a transparent manner to allow stakeholders to comprehend the intricacies and tradeoffs inherent in a footprint analysis or LCA. For these reasons, SURF recommends that this guidance be used when a footprint analysis or LCA is completed for a remediation project. © 2011 Wiley Periodicals, Inc.
Metrics for integrating sustainability evaluations into remediation projects
Authors: Butler Paul Brandt , Larsen‐Hallock Lorraine , Lewis Raymond , Glenn Christopher , Armstead Robert 
Published: June 2011

AbstractThe US Sustainable Remediation Forum (SURF) created a compilation of metrics (Metrics Toolbox) in response to a need for a broad set of metrics that could be used to assess and monitor the effectiveness of remedies in achieving sustainability goals. Metrics are the key impacts, outcomes, or burdens that are to be assessed or balanced to determine the influences and impacts of a remedial action. Metrics can reflect any of the three aspects of sustainability (i.e., environmental, social, or economic) or a combination of these aspects. Regardless, metrics represent the most critical sustainable outcomes from the perspective of the key stakeholders. The Metrics Toolbox is hosted online at www.sustainableremediation.org/library/guidance‐tools‐and‐other‐resources. By selecting metrics from the Metrics Toolbox as a starting point and considering a potentially wider suite of metrics in remedial program decisions, appropriate assessments can be made. Qualitative and quantitative metrics are tabulated for each remedial phase: remedial investigation, remedy selection, remedial design, remedial construction, operation and maintenance, and closure. Attributes for each metric are described so that remediation practitioners and key stakeholders can view the universe of metrics available and select the most relevant, site‐specific metrics for a particular site. For this reason, SURF recommends that remediation practitioners consider the metrics compiled in the Metrics Toolbox as a companion to the sustainable remediation framework published elsewhere in this journal and other sustainability evaluations. © 2011 Wiley Periodicals, Inc.
Web‐based automated remediation performance monitoring and visualization of contaminant mass flux and discharge
Authors: Kram Mark L. , Airhart Steve , Tyler Daniel , Dindal Amy , Barton Andrew , McKernan John L. , Gustafson Gregg 
Published: June 2011

AbstractEnvironmental monitoring, data processing, and reporting methods are expensive, labor‐ and resource‐intensive, time‐consuming, and often inaccurate. An innovative project management platform was developed for integrating environmental monitoring sensors, telemetry, geographical information systems, models, and geostatistical algorithms for automatically generating contour maps and time‐stamped renderings of sensor attributes and multivariate analyses. More specifically, algorithms converting sensor‐derived head and solute concentration values allow for automated monitoring of mass flux and discharge to evaluate groundwater remediation system performance and contaminant discharges from aquifers to surface‐water receptors. Life‐cycle costs and carbon footprints were reduced due to the elimination of energy and labor expenditures associated with transportation, data collection, laboratory efforts, report generation, and information dissemination. A brief summary of two demonstrations of this sensor‐based water resources management application is presented. © 2011 Wiley Periodicals, Inc.
Development of a waterjet system for direct delivery of granular iron and activated carbon to remediate contaminated aqueous sediments
Authors: Risley Gavin H. R. , Elmore Andrew Curtis , Burken Joel G. , Galecki Grzegorz 
Published: June 2011

AbstractWhile the techniques and technologies associated with contaminated sediment remediation are relatively mature, there are several issues associated with these practices that make them unattractive. The inability of currently used mechanical mixing implements to place amendments in aqueous environments and their intrusive behavior toward benthic communities are just two examples of a necessity for an improved delivery method. Waterjets may be a viable option for placement of particulate remediation amendments, such as activated carbon and granular iron, at depth. A custom waterjet nozzle and injection system has been fabricated by the authors to examine this delivery concept. The developed injection system's performance was tested by characterizing the waterjet‐delivered amendment (activated carbon and granular iron) distributions in a surrogate sediment. The delivered amendment distributions followed similar patterns for a range of injection times and a variety of amendments. The injection depths, however, were dependent upon the type of amendment being injected. These findings have led to a better understanding of what occurs during an amendment injection, which can be used for a more controlled placement of remediation amendments using this technique in the future. The laboratory results indicate that the subject waterjet system may have the potential for field‐scale applications, especially for granular iron delivery, as the authors were able to place between 60 and 70 wt percent into a surrogate sediment bed along the path of injection. © 2011 Wiley Periodicals, Inc.
Nature, frequency, and cost of environmental remediation at onshore oil and gas exploration and production sites
Authors: Connor John A. , Molofsky Lisa J. , Paquette Shawn M. , Hinchee Robert E. , Desai Shilpi P. , Connor Miriam K. 
Published: June 2011

AbstractThis article quantifies the nature, frequency, and cost of environmental remediation activities for onshore oil and gas operations, as determined from over 4,100 environmental remediation cases in Texas, Kansas, New Mexico, and Colorado. For the purpose of this article, “remediation'' refers to cleanup efforts that entail longer‐term site characterization, monitoring, and remedial action beyond the initial spill cleanup or emergency response stage. In addition, data are also presented regarding short‐term spill cleanup activities in two of the four states. © 2011 Wiley Periodicals, Inc.