bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic stent and catheter marker detection in X-ray fluoroscopy using adaptive thresholding and classification
Authors: Chabi Negar , Beuing Oliver , Preim Bernhard , Saalfeld Sylvia 
Published: September 2020

Abstract
In this study, we propose a method for marker detection in X-ray fluoroscopy sequences based on adaptive thresholding and classification. Adaptive thresholding yields multiple marker candidates. To remove non-marker areas, 24 specific features are extracted from each extracted patch and four supervised classifiers are trained to differentiate non-marker areas from marker areas. Quantitative evaluation was carried out to assess different classifier performance by calculating accuracy, sensitivity, specificity and precision. SVM outperforms other classifiers based on the mean value for accuracy, specificity and precision with 81.56, 91.94 and 84.21%, respectively.
Endoscopic filter fluorometer for detection of accumulation of Protoporphyrin IX to improve photodynamic diagnostic (PDD)
Authors: Boese Axel , Wagner Alexander , Illanes Alfredo , Liehr Uwe Bernd , Wendler Johann Jakob , Friebe Michael 
Published: September 2020

Abstract
Photodynamic diagnostic (PDD) is an optical enhancement option for the endoscope to support the detection of cancer, for example in the bladder. In real application PDD efficiency suffers due to the complex accumulation of the photosensitizing drug inside the tumor and the associated processes of heme syntheses to create the fluorescent components needed. To optimize the diagnostic outcome of PDD it would be helpful to predict the optimal time for diagnosis based on measurable precursors. In a previous cell study, we proposed a new filter fluorometer to image the accumulation of the precursors Coproporphyrin III (CP-III) and Uroporphyrin III (UP-III) that metabolize to Protoporphyrin IX (PP-IX) later. This accumulation process can be used to predict the optimal time slot for diagnostic imaging. Therefore, a new filter system was designed to distinguish between CP-III and PP-IX. In this work we tested this filter system in combination with a standard PDD endoscopic imaging system. Goal of this study was to prove the technical feasibility in a non-patient setup to prepare a later clinical study.
Guided capture of 3-D Ultrasound data and semiautomatic navigation using a mechatronic support arm system
Authors: Francis Amalanesan Antony , Ostler Daniel , Frielinghaus Nils , Heiliger Thomas , Wilhelm Dirk 
Published: September 2020

Abstract
A common treatment for malignant hepatic tumors is radiofrequency thermal ablation (RFA); however this procedure is often exhausting and error-prone, when performed only with hand held devices. In this work, we present a new concept for a computer- and mechatronic-arm-assisted treatment of hepatic tumor with RFA. Challenging factors of state-of-the-art RFA procedures are tackled by utilizing a prototype, which combines state-of-the-art ultrasound image guidance with a mechatronic support arm system. Physicians can image and examine the human abdomen using an ultrasound capturing device which is guided by the mechatronic support arm. The mechatronic arm allows to track the ultrasound transducer via joint position encoders, so that the recorded images’ exact positions are acquired and the patient is automatically registered during imaging. Consequently, physicians can use the acquired ultrasound images to navigate in the imaged abdomen area. The established prototype enables preplanning and semi-automatic alignment of trajectories with sufficient accuracy. In addition, the arm system supports the usually lengthy, exhausting and error-prone holding of the needle during the ablation process. Based on the results of accuracy examination and expert assessments by surgeons, the established concept could be proven to be advantageous for the considered use case.
Intraventricular flow features and cardiac mechano-energetics after mitral valve interventions – feasibility of an isolated heart model
Authors: Vellguth Katharina , Sündermann Simon , Escher Andreas , Bierewirtz Tim , Schmidt Tanja , Alogna Alessio , Kertzscher Ulrich , Goubergrits Leonid , Fraser Katharine H. , Granegger Marcus 
Published: September 2020

Abstract
The aim of this work was the development of an isolated heart setup to delineate the interactions between intraventricular flow features, hemodynamic parameters and mechano-energetics after certain mitral valve therapies. Five porcine hearts were explanted and prepared for (i) edge-to-edge mitral valve repair, (ii) implantation of a rotatable biscupid mechanical valve prosthesis. Flow structures were visualized using echocardiography while hemodynamics was recorded in terms of pressures, flow rates and ventricular volume. Hemodynamic and cardiac mechano-energetics implied a marginal effect (<5%) of alternating leaflet orientation on ventricular pre-load and stroke work. After edge-to-edge repair, substantial variations in flow structures were observed. Beside promoting profound insights into fundamental physiologic mechanisms, the setup may be used for validation of computer aided therapy planning tools.
Multicriterial CNN based beam generation for robotic radiosurgery of the prostate
Authors: Gerlach Stefan , Fürweger Christoph , Hofmann Theresa , Schlaefer Alexander 
Published: September 2020

Abstract
Although robotic radiosurgery offers a flexible arrangement of treatment beams, generating treatment plans is computationally challenging and a time consuming process for the planner. Furthermore, different clinical goals have to be considered during planning and generally different sets of beams correspond to different clinical goals. Typically, candidate beams sampled from a randomized heuristic form the basis for treatment planning. We propose a new approach to generate candidate beams based on deep learning using radiological features as well as the desired constraints. We demonstrate that candidate beams generated for specific clinical goals can improve treatment plan quality. Furthermore, we compare two approaches to include information about constraints in the prediction. Our results show that CNN generated beams can improve treatment plan quality for different clinical goals, increasing coverage from 91.2 to 96.8% for 3,000 candidate beams on average. When including the clinical goal in the training, coverage is improved by 1.1% points.
Needle placement accuracy in CT-guided robotic post mortem biopsy
Authors: Gromniak Martin , Neidhardt Maximilian , Heinemann Axel , Püschel Klaus , Schlaefer Alexander 
Published: September 2020

Abstract
Forensic autopsies include a thorough examination of the corpse to detect the source or alleged manner of death as well as to estimate the time since death. However, a full autopsy may be not feasible due to limited time, cost or ethical objections by relatives. Hence, we propose an automated minimal invasive needle biopsy system with a robotic arm, which does not require any online calibrations during a procedure. The proposed system can be easily integrated into the workflow of a forensic biopsy since the robot can be flexibly positioned relative to the corpse. With our proposed system, we performed needle insertions into wax phantoms and livers of two corpses and achieved an accuracy of 4.34 ± 1.27 mm and 10.81 ± 4.44 mm respectively.
Segmentation of the distal femur in ultrasound images
Authors: Hohlmann Benjamin , Glanz Jakob , Radermacher Klaus 
Published: September 2020

Abstract

Objectives
Ultrasound is a widely used imaging technology that allows for fast diagnosis of a broad range of illnesses and injuries of the musculoskeletal system. However, interpreting ultrasound images remains a challenging task that requires expert knowledge and years of training for each exam. One crucial step for the long-term goal of automatic diagnosis is pixel wise semantic segmentation.

Methods
In this work, several state-of-the-art semantic segmentation networks were trained on a new dataset of manually annotated ultrasound images depicting the distal femur.

Results
PSP-Net achieved the best overall performance with an average surface distance error (SDE) of 0.64 mm.

Conclusions
We recommend the PSP-Net architecture for semantic segmentation of bone surfaces.
Shrinking tube mesh: combined mesh generation and smoothing for pathologic vessels
Authors: Niemann Annika , Preim Bernhard , Saalfeld Sylvia 
Published: September 2020

Abstract
We present a mesh generation algorithm which is able to produce smooth meshes from point clouds derived from histological slices. In this work, the shrinking tube mesh generation is used on histologic images depicting pathologic vessels. Our mesh generation is modeled after the behaviour of a shrinking tube. A start shape is fitted iteratively to the point cloud. The presented algorithm was successfully used to generate meshes of the inner and outer contour from vessels in histologic images. While histologic slices have a high in-plane resolution, the large slice distance and deformations during tissue deformations are challenging for 3D model generation.
Target tracking accuracy and latency with different 4D ultrasound systems – a robotic phantom study
Authors: Ipsen Svenja , Böttger Sven , Schwegmann Holger , Ernst Floris 
Published: September 2020

Abstract
Ultrasound (US) imaging, in contrast to other image guidance techniques, offers the distinct advantage of providing volumetric image data in real-time (4D) without using ionizing radiation. The goal of this study was to perform the first quantitative comparison of three different 4D US systems with fast matrix array probes and real-time data streaming regarding their target tracking accuracy and system latency. Sinusoidal motion of varying amplitudes and frequencies was used to simulate breathing motion with a robotic arm and a static US phantom. US volumes and robot positions were acquired online and stored for retrospective analysis. A template matching approach was used for target localization in the US data. Target motion measured in US was compared to the reference trajectory performed by the robot to determine localization accuracy and system latency. Using the robotic setup, all investigated 4D US systems could detect a moving target with sub-millimeter accuracy. However, especially high system latency increased tracking errors substantially and should be compensated with prediction algorithms for respiratory motion compensation.
Using position-based dynamics to simulate deformation in aortic valve replacement procedure
Authors: Walczak Lars , Goubergrits Leonid , Hüllebrand Markus , Georgii Joachim , Falk Volkmar , Hennemuth Anja 
Published: September 2020

Abstract
We present a novel approach to simulate deformation in aortic valve replacement scenarios with applications in operation planning and batch domain creation for large computational fluid dynamics studies of the aortic arch.
Comprehensive performance test and analysis of graphene-enhanced chromium-free Dacromet coating
Authors: Cai Jiabin , Shi Xiaojie , Song Jian , Song Junjun , Jing Fuqi , Xiao Qihong 
Published: September 2020

Abstract
The proposed work aims to improve the comprehensive properties of the composite coating by adding different content of graphene into the coating solution. Firstly, the formulation of the coating solution was determined by the L16(45) orthogonal test. Secondly, the conventional properties of the coating were tested using the optical microscope and micro-vickers hardness tester. Thirdly, the corrosion resistance of the coating was tested by the rapid ammonium nitrate corrosion test, immersion test, and neutral salt spray test. The changes of the microstructure and composition of the coating before and after corrosion were observed and analyzed using the scanning electron microscope, energy dispersive spectrometer, X-ray diffractometer, and Raman spectrometer, and the Tafel polarization curves and electrochemical impedance spectroscopy of the composite coatings with different graphene contents were tested by electrochemical experiments. The results show that the hardness of the coating increases with the increase in the content of graphene. Graphene intercalates between zinc and aluminum powders in a flaky structure, which reduces the appearance of voids and enhances the protection of chromium-free Dacromet coatings, slows down the penetration of electrolyte solutions and effectively slows down the penetration of corrosive media. The addition of a small amount of graphene can increase the corrosion potential and decrease the corrosion current density of the chromium-free Dacromet coating, the Nyquist low frequency of the coating is higher in the same period and the salt spray resistance of the coating is the best.
Random effects tumour growth models for identifying image markers of mammography screening sensitivity
Authors: Abrahamsson Linda , Alsheh Ali Maya , Czene Kamila , Isheden Gabriel , Hall Per , Humphreys Keith 
Published: September 2020

Abstract

Introduction
Percentage mammographic density has long been recognised as a marker of breast cancer risk and of mammography sensitivity. There may be other image markers of screening sensitivity and efficient statistical approaches would be helpful for establishing them from large scale epidemiological and screening data.

Methods
We compare a novel random effects continuous tumour growth model (which includes a screening sensitivity submodel) to logistic regression (with interval vs. screen-detected cancer as the dependent variable) in terms of statistical power to detect image markers of screening sensitivity. We do this by carrying out a simulation study. We also use continuous tumour growth modelling to quantify the roles of dense tissue scatter (measured as skewness of the intensity gradient) and percentage mammographic density in screening sensitivity. This is done by using mammograms and information on tumour size, mode of detection and screening history from 1,845 postmenopausal women diagnosed with invasive breast cancer, in Sweden between 1993 and 1995.

Results
The statistical power to detect a marker of screening sensitivity was larger for our continuous tumour growth model than it was for logistic regression. For the settings considered in this paper, the percentage increase in power ranged from 34 to 56%. In our analysis of data from Swedish breast cancer patients, using our continuous growth model, when including both percentage mammographic density and dense tissue scatter in the screening sensitivity submodel, only the latter variable was significantly associated with sensitivity. When included one at a time, both markers were significantly associated (p-values of 5.7 × 10−3 and 1.0 × 10−5 for percentage mammographic density and dense tissue scatter, respectively).

Conclusions
Our continuous tumour growth model is useful for finding image markers of screening sensitivity and for quantifying their role, using large scale epidemiological and screening data. Clustered dense tissue is associated with low mammography screening sensitivity.
Mathematical modeling the epicenters of coronavirus disease-2019 (COVID-19) pandemic
Authors: Jamshidi Babak , Rezaei Mansour , Jamshidi Zargaran Shahriar , Najafi Farid 
Published: September 2020

Abstract
In epidemiology, the modeling of epicenters is important both conceptually and mathematically. This paper is an attempt to model epicenters mathematically. We present an algorithm to find new epicenters. Applying our model for the data related to COVID-19 pandemic, we obtain epicenters in China, South Korea, Iran, Italy, France, Germany, Spain, the USA, and Switzerland, on the days 1, 35, 42, 42, 49, 50, 50, 50, and 56, respectively. Although the number of these epicenters is less than 5% of all contaminated countries across the globe, as of March 22, 2020, they make up 74% of new cases and over 80% of total confirmed cases. Finally, we conclude that we expect to face three new epicenters between March 22 and April 1, 2020.
Effectiveness of neurobic exercise program on memory and depression among elderly residing at old age home
Authors: Raj Divya , Santhi Subramaniam , Sapharina G. J. Sara 
Published: September 2020

Abstract

Objectives
This study finds out the effectiveness of neurobic exercise program on memory and depression among elderly residing in old age homes.

Methods
The non-probability purposive sampling technique was used for sample selection. Wechsler's memory scale (WMS-IV) and Geriatric depression scale (GDS) were the instruments used to assess the memory and depression among elderly during the pretest and posttest, respectively and the researcher had developed data sheet to collect information about the background variables using interview technique.

Results
The neurobic exercise program was found to be effective in reducing depression among elderly residing in old age homes. There was a significant difference (p<0.001) in the level of depression had been found during the pretest and posttest in the interventional group. There was a statistically significant difference (p<0.001) found between the study group and in the control group. There was significant correlation (r=0.417, p<0.05) found between the memory and depression during the pretest in the study group among the elderly. A statistically significant association (p<0.05) found in the mean scores of depression and marital status of the elderly during the pretest in the study group and there was a significant association (p<0.01) found in the mean scores of depression and the gender of the elderly during the pretest and posttest in the non interventional group were found.

Conclusions
The findings suggested that neurobic exercise program is an effective intervention in improving memory and reducing depression.
Topological nanophotonics for photoluminescence control
Authors: Tripathi Aditya , Kruk Sergey , Shang Yunfei , Zhou Jiajia , Kravchenko Ivan , Jin Dayong , Kivshar Yuri 
Published: September 2020

AbstractObjectivesRare-earth-doped nanocrystals are emerging light sources that can produce tunable emissions in colours and lifetimes, which has been typically achieved in chemistry and material science. However, one important optical challenge – polarization of photoluminescence – remains largely out of control by chemistry methods. Control over photoluminescence polarization can be gained via coupling of emitters to resonant nanostructures such as optical antennas and metasurfaces. However, the resulting polarization is typically sensitive to position disorder of emitters, which is difficult to mitigate.MethodsRecently, new classes of disorder-immune optical systems have been explored within the framework of topological photonics. Here we explore disorder-robust topological arrays of Mie-resonant nanoparticles for polarization control of photoluminescence of nanocrystals.ResultsWe demonstrate polarized emission from rare-earth-doped nanocrystals governed by photonic topological edge states supported by zigzag arrays of dielectric resonators. We verify the topological origin of polarized photoluminescence by comparing emission from nanoparticles coupled to topologically trivial and nontrivial arrays of nanoresonators.ConclusionsWe expect that our results may open a new direction in the study of topology-enable emission properties of topological edge states in many photonic systems.
Strong spin–orbit interaction of photonic skyrmions at the general optical interface
Authors: Shi Peng , Du Luping , Yuan Xiaocong 
Published: September 2020

Abstract
Photonic skyrmions have applications in many areas, including the vectorial and chiral optics, optical manipulation, deep-subwavelength imaging and nanometrology. Much effort has been focused on the experimental characterization of photonic skyrmions. Here, we give an insight into the spin and orbital features of photonic skyrmions constructed by the p-polarized and s-polarized surface waves at an interface with various electric and magnetic properties by analyzing the continuity of chirality, energy flow and momentum densities through the electric and magnetic interface. The continuity of chirality density indicates that the photonic skyrmion has a property of the optical transverse spin. Most importantly, the continuity of energy flow and momentum densities results in four spin–orbit interaction quantities, which indicate the gradient of electric polarizability or permeability governs the spin–orbit interaction of photonic skyrmions and leads to the discontinuity and even the reversal of spin orientation through the optical interface. Our investigations on the spin–orbit properties of photonic skyrmions, which can give rise to the spin-dependent force and topological unidirectional transportation, is thorough and can be extended to other classical wave, such as acoustic and fluid waves. The findings help in understanding the spin–orbit feature of photonic topological texture and in constructing further optical manipulation, sensing, quantum and topological techniques.
Exploring Public Perceptions of Nonprofit Policy Advocacy
Authors: Bell Elizabeth , Fryar Alisa Hicklin , Johnson Tyler 
Published: September 2020

Abstract
Research on nonprofit advocacy has grown in recent years, and many nonprofit organizations have expanded and refined their efforts to influence public policies in ways they believe will benefit society. Despite the growing body of literature on nonprofit advocacy, there is substantial room for development on questions related to public perceptions of nonprofit advocacy activities. Utilizing an experimental design, we examine the ways in which the involvement of a nonprofit organization in the policy process can shift public opinion regarding a specific policy proposal. We also explore how these perceptions vary when we introduce political conflict that questions the effectiveness of the proposed policy. We find that in the absence of political controversy, the involvement of nonprofits in the policy process can significantly increase positive perceptions, relative to the control condition in which there is no mention on nonprofit involvement. However, we also find that the ways in which nonprofit involvement could boost support for a policy proposal may not hold when there is conflict over the policy in question.
Chlorine dioxide bleaching of nineteen non-wood plant pulps
Authors: Ferdous Taslima , Quaiyyum M. A. , Jahan M. Sarwar 
Published: September 2020

AbstractBleaching of unbleached and oxygen delignified pulps from nineteen non-wood plants has been evaluated in elemental chlorine free bleaching. Chlorine dioxide charge (kappa factor 0.15, 0.20 and 0.25) and temperature (70 and 85 °C) in the delignification stage (D) were varied. Chlorine dioxide (ClO2) charge and temperature exhibited lower kappa number and higher brightness after alkaline extraction (EP) stage. High temperature ClO2delignification (DHT) exhibited higher final pulp brightness. The final brightness of wheat straw pulp reached to 90 % after D0/DHT(EP)D1bleaching, while banana pseudo stem pulp showed the worst bleachability. Residual hexeneuronic acid contents in final pulp from most of the non-wood plants were lower and exhibited 1–2 % higher pulp brightness in DHTprocess than D0process. Oxygen delignified pulp and DHTprocess discharged lower COD load.