bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Simulations of Two Coaxial Vortex Rings Head-on Collision
Authors: Guan Hui , Wei Zhi-Jun , Rasolkova Elizabeth Rumenova , Wu Chui-Jie 
Published: May 2016

AbstractVortex rings have been a subject of interest in vortex dynamics due to a plethora of physical phenomena revealed by their motions and interactions within a boundary. The present paper is devoted to physics of a head-on collision of two vortex rings in three dimensional space, simulated with a second order finite volume scheme and compressible. The scheme combines non-iterative approximate Riemann-solver and piecewise-parabolic reconstruction used in inviscid flux evaluation procedure. The computational results of vortex ring collisions capture several distinctive phenomena. In the early stages of the simulation, the rings propagate under their own self-induced motion. As the rings approach each other, their radii increase, followed by stretching and merging during the collision. Later, the two rings have merged into a single doughnut-shaped structure. This structure continues to extend in the radial direction, leaving a web of particles around the centers. At a later time, the formation of ringlets propagate radially away from the center of collision, and then the effects of instability involved leads to a reconnection in which small-scale ringlets are generated. In addition, it is shown that the scheme captures several experimentally observed features of the ring collisions, including a turbulent breakdown into small-scale structures and the generation of small-scale radially propagating vortex rings, due to the modification of the vorticity distribution, as a result of the entrainment of background vorticity and helicity by the vortex core, and their subsequent interaction.
Unified a Priori Error Estimate and a Posteriori Error Estimate of CIP-FEM for Elliptic Equations
Authors: Wang Jianye , Ma Rui 
Published: May 2016

AbstractThis paper is devoted to a unified a priori and a posteriori error analysis of CIP-FEM (continuous interior penalty finite element method) for second-order elliptic problems. Compared with the classic a priori error analysis in literature, our technique can easily apply for any type regularity assumption on the exact solution, especially for the case of lowerH1+sweak regularity under consideration, where 0 ≤s≤ 1/2. Because of the penalty term used in the CIP-FEM, Galerkin orthogonality is lost and Céa Lemma for conforming finite element methods can not be applied immediately when 0≤s≤1/2. To overcome this difficulty, our main idea is introducing an auxiliaryC1finite element space in the analysis of the penalty term. The same tool is also utilized in the explicit a posteriori error analysis of CIP-FEM.
Numerical Investigation and Wind Tunnel Validation on Near-Wake Vortical Structures of Wind Turbine Blades
Authors: Zhang Zhenyu , Chen Li , Wang Tongguang 
Published: May 2016

AbstractComputational fluid dynamics (CFD) has been used by numerous researchers for the simulation of flows around wind turbines. Since the 2000s, the experiments of NREL phase VI blades for blind comparison have been a de-facto standard for numerical software on the prediction of full scale horizontal axis wind turbines (HAWT) performance. However, the characteristics of vortex structures in the wake, whether for modeling the wake or for understanding the aerodynamic mechanisms inside, are still not thoroughly investigated. In the present study, the flow around N-REL phase VI blades was numerically simulated, and the results of the wake field were compared with the experimental ones of a one-to-eight scaled model in a low-speed wind tunnel. A good agreement between simulation and experimental results was achieved for the evaluation of overall performances. The simulation captured the complete formation procedure of tip vortex structure from the blade. Quantitative analysis showed the streamwise translation movement of vortex cores. Both the initial formation and the damping of vorticity in near wake field were predicted. These numerical results showed good agreements with the measurements. Moreover, wind tunnel wall effects were also investigated on these vortex structures, and it revealed further radial expansion of the helical vortical structures in comparison with the free-stream case.
Spectral-Collocation Method for Volterra Delay Integro-Differential Equations with Weakly Singular Kernels
Authors: Shi Xiulian , Chen Yanping 
Published: May 2016

AbstractA spectral Jacobi-collocation approximation is proposed for Volterra delay integro-differential equations with weakly singular kernels. In this paper, we consider the special case that the underlying solutions of equations are sufficiently smooth. We provide a rigorous error analysis for the proposed method, which shows that both the errors of approximate solutions and the errors of approximate derivatives decay exponentially inL∞norm and weightedL2norm. Finally, two numerical examples are presented to demonstrate our error analysis.
Between Film, Video, and the Digital
Authors: Kim Jihoon 
Published: May 2016

Encompassing experimental film and video, essay film, gallery-based installation art, and digital art, Jihoon Kim establishes the concept of hybrid moving images as an array of impure images shaped by the encounters and negotiations between different media, while also using it to explore various theoretical issues, such as stillness and movement, indexicality, abstraction, materiality, afterlives of the celluloid cinema, archive, memory, apparatus, and the concept of medium as such.
Grounding its study in interdisciplinary framework of film studies, media studies, and contemporary art criticism, Between Film, Video, and the Digital offers a fresh insight on the post-media conditions of film and video under the pervasive influences of digital technologies, as well as on the crucial roles of media hybridity in the creative processes of giving birth to the emerging forms of the moving image. Incorporating in-depth readings of recent works by more than thirty artists and filmmakers, including Jim Campbell, Bill Viola, Sam Taylor-Johnson, David Claerbout, Fiona Tan, Takeshi Murata, Jennifer West, Ken Jacobs, Christoph Girardet and Matthias Müller, Hito Steyerl, Lynne Sachs, Harun Farocki, Doug Aitken, Douglas Gordon, Stan Douglas, Candice Breitz, among others, the book is the essential scholarly monograph for understanding how digital technologies simultaneously depend on and differ film previous time-based media, and how this juncture of similarities and differences signals a new regime of the art of the moving image.
Evaluation of multifrequency range imaging technique implemented on the Chung–Li VHF atmospheric radar
Authors: Chen Jenn-Shyong , Tsai Shih-Chiao , Su Ching-Lun , Chu Yen-Hsyang 
Published: May 2016

Abstract. The multifrequency range imaging technique (RIM) has been implemented on the Chung–Li VHF array radar since 2008 after its renovation. This study made a more complete examination and evaluation of the RIM technique to facilitate the performance of the radar for atmospheric studies. RIM experiments with various radar parameters such as pulse length, pulse shape, receiver bandwidth, transmitter frequency set, and so on were conducted. The radar data employed for the study were collected from 2008 to 2013. It has been shown that two factors, the range/time delay of the signal traveling in the media and the standard deviation of Gaussian-shaped range-weighting function, play crucial roles in ameliorating the RIM-produced brightness (or power distribution); the two factors are associated with some radar parameters and system characteristics. The range/time delay of the signal was found to increase with time; moreover, it was slightly different for the echoes from the atmosphere with and without the presence of significant precipitation. A procedure of point-by-point correction of range/time delay was thus executed for the presence of precipitation to minimize the bogus brightness discontinuity at range gate boundaries. With the RIM technique, the Chung–Li VHF radar demonstrates its first successful observation of double-layer structures as well as their temporal and spatial variations with time.
Sensitivity of biogenic volatile organic compounds to land surface parameterizations and vegetation distributions in California
Authors: Zhao Chun , Huang Maoyi , Fast Jerome D. , Berg Larry K. , Qian Yun , Guenther Alex , Gu Dasa , Shrivastava Manish , Liu Ying , Walters Stacy , Pfister Gabriele , Jin Jiming , Shilling John E. , Warneke Carsten 
Published: May 2016

Abstract. Current climate models still have large uncertainties in estimating biogenic trace gases, which can significantly affect atmospheric chemistry and secondary aerosol formation that ultimately influences air quality and aerosol radiative forcing. These uncertainties result from many factors, including uncertainties in land surface processes and specification of vegetation types, both of which can affect the simulated near-surface fluxes of biogenic volatile organic compounds (BVOCs). In this study, the latest version of Model of Emissions of Gases and Aerosols from Nature (MEGAN v2.1) is coupled within the land surface scheme CLM4 (Community Land Model version 4.0) in the Weather Research and Forecasting model with chemistry (WRF-Chem). In this implementation, MEGAN v2.1 shares a consistent vegetation map with CLM4 for estimating BVOC emissions. This is unlike MEGAN v2.0 in the public version of WRF-Chem that uses a stand-alone vegetation map that differs from what is used by land surface schemes. This improved modeling framework is used to investigate the impact of two land surface schemes, CLM4 and Noah, on BVOCs and examine the sensitivity of BVOCs to vegetation distributions in California. The measurements collected during the Carbonaceous Aerosol and Radiative Effects Study (CARES) and the California Nexus of Air Quality and Climate Experiment (CalNex) conducted in June of 2010 provided an opportunity to evaluate the simulated BVOCs. Sensitivity experiments show that land surface schemes do influence the simulated BVOCs, but the impact is much smaller than that of vegetation distributions. This study indicates that more effort is needed to obtain the most appropriate and accurate land cover data sets for climate and air quality models in terms of simulating BVOCs, oxidant chemistry and, consequently, secondary organic aerosol formation.
Trabecular Titanium™ Cups and Augments in Revision Total Hip Arthroplasty: Clinical Results, Radiology and Survival Outcomes
Authors: Gallart Xavier , Fernández-Valencia Jenaro A. , Riba Josep , Bori Guillem , García Sebastián , Tornero Eduard , Combalía Andreu 
Published: May 2016

Background Large acetabular defects remain a challenge in hip revision arthroplasty. Experience with Trabecular Titanium™ (TT) cups (Limacorporate S.p.a.) has not been widely reported. Therefore, we assessed the survivorship and clinical and radiological outcomes of patients receiving TT cups, with or without supplementary trabecular titanium hemispherical modules for acetabular reconstruction, in primary and revision total hip arthroplasty (THA). Methods Between January 2009 and July 2014, we performed 67 revisions and 5 primary THAs using TT cups in 69 patients. To achieve stability and/or restore the hip's centre of rotation, hemispherical modules were used in 17 cases based on pre-operative templating and/or intraoperative findings. Mean follow-up was 30.5 months. Acetabular bone defects were classified according to the Paprosky classification. Survivorship, functional outcomes (Merle d'Aubigné) and radiological outcomes were analysed. Results 8 patients underwent cup revision: 2 for loosening, 3 for infection, and 3 for hip dislocation. The remaining cases did not present radiological signs of loosening. None of the cases with Paprosky type I classifications needed revision, while 4 with type II and 4 with type III needed revision (p = 0.028). The respective mean values for pain, walking, and range of motion (Merle d'Aubigné scores ± standard deviation) were 3.6 ± 1.4, 3.7 ± 0.7, and 3.8 ± 0.6 pre-operatively, and 5.7 ± 0.7, 5.3 ± 0.7, and 5.6 ± 0.7 at the latest follow-up (p<0.001). Conclusions In the short term, results with TT cups appear to be encouraging, with satisfactory survival rates for both simple and complex cases.
Role of Tetrasomy for the Diagnosis of Urothelial Carcinoma Using UroVysion Fluorescent In Situ Hybridization
Authors: Zhou Amy G. , Liu Yuxin , Cyr Maryann St. , Garver Joanne , Woda Bruce A. , Cosar Ediz F. , Hutchinson Lloyd M. 
Published: May 2016

Context.—UroVysion fluorescent in situ hybridization (FISH) is routinely used to detect urothelial carcinoma (UC). A positive threshold is defined as chromosome polysomy in 4 or more cells, which also includes tetrasomy, a natural product of cell division.
Objectives.—To evaluate tetrasomy for UC detection and explore the relation to the surgical diagnosis or patient history.
Design.—The FISH was performed on 1532 urine samples from patients with cytology results and 4 or more years of follow-up. We created separate polysomy and tetrasomy categories and constructed receiver operating curves to determine appropriate thresholds using biopsy (n = 194) as the gold standard. Standard FISH and a novel assay integrating cytomorphology and FISH (Target-FISH) were compared. Matching tissue biopsies of urine samples with 10 or more tetrasomy cells were analyzed.
Results.—No significant threshold was found for tetrasomy cells. Exclusion of tetrasomy from the polysomy category changed the threshold from 8.5 to 4.5 cells, increased specificity (59.2% to 78.9%), but reduced sensitivity (78.9% to 65.9%). In Target-FISH, the same approach yielded a specificity of 93.7% and sensitivity of 65.2%. Similarly, specificity improved significantly for low- and high-grade UC, but sensitivity decreased for low-grade UC. No evidence of UC was observed in 95% (52 of 55) of the patients referred for screening who had 10 or more tetrasomy cells by FISH. Matching biopsies for urines containing 10 or more tetrasomy cells showed few or no tetrasomy cells.
Conclusions.—Tetrasomy is a nonspecific finding frequently encountered in urine FISH and should be excluded from the polysomy classification. Target-FISH is an optimal approach, offering the ability to detect rare tetrasomy tumors.
Monitoring of the Clonal Fraction by Fluorescence In Situ Hybridization in Myelodysplastic Syndrome: Comparison With International Working Group Treatment Response Criteria
Authors: Park Jae Hyeon , Kim Miyoung , Kong Sun-Young , Yoon Sung-Soo , Lee Dong Soon 
Published: May 2016

At the initial diagnosis of myelodysplastic syndrome (MDS) and/or during follow-up, the evaluation of chromosomal abnormalities is based on standard G-banding, whereas the utility of fluorescence in situ hybridization (FISH) is still debated.Context.—
To investigate whether interphase fluorescence in situ hybridization (iFISH) clone size at initial diagnosis of MDS is correlated with survival and whether changes in clonal fraction by iFISH are concordant with the MDS International Working Group response criteria during follow-up.Objectives.—
A tailored FISH panel (−5/5q−, −7/7q−, +8, −20/20q−, and +1/1q+), based on reported cytogenetic changes in Korean patients with MDS, was performed in 81 patients with MDS at initial diagnosis and in 28 patients during follow-up.Design.—
During follow-up, absolute increases in the clone size by iFISH by 20% or more, with relative increases of 50% or more, compared with previous specimens, were associated with transformation to acute myeloid leukemia (P = .001 and P = .002, respectively). Of the 28 patients with abnormal iFISH results, 7 (25%) showed discordance between iFISH and MDS International Working Group responses. Concordance between clone size by G-banding and iFISH was higher in the refractory cytopenia with unilineage dysplasia/refractory cytopenia with multilineage dysplasia group during follow-up, whereas the group with refractory anemia with excess blasts showed higher correlation at initial diagnosis.Results.—
We conclude that iFISH can provide additional prognostic information and can predict the response to therapy in MDS.Conclusions.—
Clinicopathologic Threshold of Acute Colorectal Graft-versus-Host Disease
Authors: Gomez Adam J. , Arai Sally , Higgins John P. , Kambham Neeraja 
Published: May 2016

Colon biopsies are often used to determine the presence and severity of acute gastrointestinal graft-versus-host disease following bone marrow transplant.Context.—
To establish a threshold consensus within our institution on the number of crypt apoptotic bodies (CAB) indicative of grade 1 acute colorectal graft-versus-host disease, we retrospectively reviewed colon biopsies from posttransplant patients and incorporated clinical and endoscopic findings to validate recently proposed minimum criteria for grade 1 graft-versus-host disease as 7 or more CAB per 10 contiguous crypts.Objective.—
Eighty-one biopsies performed for suspected graft-versus-host disease from 74 individual patients were initially stratified based on their prior (prestudy) diagnoses: no significant abnormality, grade 1 graft-versus-host disease, and descriptive diagnoses mentioning increased apoptosis. A chart review was performed to assess the clinical and endoscopic impression at the time of biopsy and to determine the subsequent management and outcome.Design.—
Twenty-six biopsies with an average of 3 CAB were considered true-negative cases, and 32 biopsies with an average of 9.75 CAB were considered true-positive cases (t = 3.95999, P &lt; .001). True-negative cases had an average density of 1.36 CAB per crypt, and true-positive cases had an average density of 2.97 CAB per crypt (t = 3.950178, P &lt; .001).Results.—
A threshold of 7 or more CAB per 10 contiguous crypts promotes appropriate treatment of grade 1 acute graft-versus-host disease after other diagnostic entities are excluded. Although this threshold is 100% specific to grade 1 acute colorectal graft-versus-host disease after other histologic mimics are excluded, this threshold has a low sensitivity (59.4%) as patients with less than 7 CAB per 10 contiguous crypts constitute a heterogeneous group.Conclusions.—
Predictive lethal proarrhythmic risk evaluation using a closed-loop-circuit cell network with human induced pluripotent stem cells derived cardiomyocytes
Authors: Nomura Fumimasa , Hattori Akihiro , Terazono Hideyuki , Kim Hyonchol , Odaka Masao , Sugio Yoshihiro , Yasuda Kenji 
Published: May 2016

Abstract
For the prediction of lethal arrhythmia occurrence caused by abnormality of cell-to-cell conduction, we have developed a next-generation in vitro cell-to-cell conduction assay, i.e., a quasi in vivo assay, in which the change in spatial cell-to-cell conduction is quantitatively evaluated from the change in waveforms of the convoluted electrophysiological signals from lined-up cardiomyocytes on a single closed loop of a microelectrode of 1 mm diameter and 20 µm width in a cultivation chip. To evaluate the importance of the closed-loop arrangement of cardiomyocytes for prediction, we compared the change in waveforms of convoluted signals of the responses in the closed-loop circuit arrangement with that of the response of cardiomyocyte clusters using a typical human ether a go-go related gene (hERG) ion channel blocker, E-4031. The results showed that (1) waveform prolongation and fluctuation both in the closed loops and clusters increased depending on the E-4031 concentration increase. However, (2) only the waveform signals in closed loops showed an apparent temporal change in waveforms from ventricular tachycardia (VT) to ventricular fibrillation (VF), which is similar to the most typical cell-to-cell conductance abnormality. The results indicated the usefulness of convoluted waveform signals of a closed-loop cell network for acquiring reproducible results acquisition and more detailed temporal information on cell-to-cell conduction.
Sonography for Complete Evaluation of Neonatal Intensive Care Unit Central Support Devices
Authors: Saul David , Ajayi Samuel , Schutzman David L. , Horrow Mindy M. 
Published: May 2016

ObjectivesNeonates in the neonatal intensive care unit often require considerable support with endotracheal tubes, umbilical arterial and venous catheters, and peripherally inserted central venous catheters. Support device evaluation with radiography exposes neonates to ionizing radiation. This study evaluated the effectiveness of sonographic localization for endotracheal tubes, umbilical arterial and venous catheters, and peripherally inserted central venous catheters.MethodsThis blinded prospective Institutional Review Board–approved, Health Insurance Portability and Accountability Act–compliant study with informed consent compared sonography to radiography for endotracheal tube, umbilical arterial and venous catheter, and peripherally inserted central venous catheter localization. Participants were consecutively recruited NICU patients of any weight, gestation, and chronologic age who had an endotracheal tube, umbilical arterial catheter, umbilical venous catheter, or peripherally inserted central venous catheter placed or adjusted and had subsequent radiographic confirmation within 24 hours. Sonographic evaluation was obtained as soon as possible, without prior review of the radiograph, and results were compared.ResultsThirty sonographic studies were performed in 25 patients (14 male and 11 female), for a total of 50 lines and tubes: 18 umbilical venous catheters, 12 umbilical arterial catheters, 11 peripherally inserted central venous catheters, and 9 endotracheal tubes. Forty‐nine support devices (98%) were visualized with sonography, all concordant with radiography. Forty‐four were correctly positioned, and 6 were malpositioned. Sonography identified the location of umbilical venous catheters in all 18 cases (100%), umbilical arterial catheters in all 12 (100%), peripherally inserted central venous catheters in 10 (91%), and endotracheal tubes in 9 (100%).ConclusionsThe effectiveness of sonography was excellent for evaluation of umbilical arterial and venous catheters, endotracheal tubes, and peripherally inserted central venous catheters. These results support the goal of further point‐of‐care training and accreditation to use sonography as a primary modality for complete evaluation of NICU support devices.
Quantifying mesoscale eddies in the Lofoten Basin
Authors: Raj R. P. , Johannessen J. A. , Eldevik T. , Nilsen J. E. Ø. , Halo I. 
Published: May 2016

AbstractThe Lofoten Basin is the most eddy rich region in the Norwegian Sea. In this paper, the characteristics of these eddies are investigated from a comprehensive database of nearly two decades of satellite altimeter data (1995–2013) together with Argo profiling floats and surface drifter data. An automated method identified 1695/1666 individual anticyclonic/cyclonic eddies in the Lofoten Basin from more than 10,000 altimeter‐based eddy observations. The eddies are found to be predominantly generated and residing locally. The spatial distributions of lifetime, occurrence, generation sites, size, intensity, and drift of the eddies are studied in detail. The anticyclonic eddies in the Lofoten Basin are the most long‐lived eddies (>60 days), especially in the western part of the basin. We reveal two hotspots of eddy occurrence on either side of the Lofoten Basin. Furthermore, we infer a cyclonic drift of eddies in the western Lofoten Basin. Barotropic energy conversion rates reveals energy transfer from the slope current to the eddies during winter. An automated colocation of surface drifters trapped inside the altimeter‐based eddies are used to corroborate the orbital speed of the anticyclonic and cyclonic eddies. Moreover, the vertical structure of the altimeter‐based eddies is examined using colocated Argo profiling float profiles. Combination of altimetry, Argo floats, and surface drifter data is therefore considered to be a promising observation‐based approach for further studies of the role of eddies in transport of heat and biomass from the slope current to the Lofoten Basin.