bluuebunny/crossref_metadata_2025_split huggingface dataset:
The BougieCap – a new method for endoscopic treatment of complex benign esophageal stenosis: results from a multicenter study
Authors: Walter Benjamin , Schmidbaur Simone , Rahman Imdadur , Albers David , Schumacher Brigitte , Meining Alexander 
Published: July 2019

Abstract
Background A major limitation of current treatment strategies for nonmalignant upper gastrointestinal stenoses is the lack of either optical or haptic feedback during dilation. Wire guidance and fluoroscopy is often necessary to control the position.
Methods A novel device for endoscopic dilation, the BougieCap (Ovesco Endoscopy AG, Tübingen, Germany) was evaluated in a prospective multicenter trial. Primary outcome was successful dilation of stenosis and secondary outcome was alteration in dysphagia symptoms in short-term follow-up.
Results 50 patients with benign esophageal strictures were included. Endoscopic bougienage was successful in 96 %. Bougienage failed in two cases because of high resistance. Symptoms of dysphagia decreased significantly after bougienage (59.0 points at Day 0 vs. 28.6 points at Day 14; P < 0.001). Adverse events were loss of BougieCap into the stomach in two cases; no severe adverse events were reported.
Conclusions Endoscopic treatment of benign stenoses using the BougieCap enabled direct visual control of the bougienage procedure. This might help to adapt treatment more precisely to the stricture. Symptoms of dysphagia were improved in short-term follow-up. Additional wire guidance may be used for selected cases (e. g. narrow lumen, pediatric scope).
Exercise with Blood Flow Restriction to Improve Quadriceps Function Long After ACL Reconstruction
Authors: Kilgas Matthew A. , Lytle Lydia L.M. , Drum Scott N. , Elmer Steven J. 
Published: July 2019

AbstractQuadriceps atrophy and weakness can persist for years after anterior cruciate ligament reconstruction (ACLR). We evaluated the effectiveness of a home-based blood flow restriction (BFR) exercise program to increase quadriceps size and strength several years after ACLR. Nine adults with ACLR (5±2 yrs post-surgery, ≤90% symmetry in quadriceps size and strength) and nine uninjured controls volunteered. ACLR participants exercised at home for 25 min, 5×/wk for 4 wks (single-leg knee extension, bodyweight half-squats, walking). Blood flow in only the involved leg was restricted using a thigh cuff inflated to 50% of limb occlusion pressure. Rectus femoris and vastus lateralis thickness and knee extensor strength were measured before and after training. Baseline and post-training symmetry (involved leg/uninvolved leg) indices were compared to uninjured controls. Rectus femoris and vastus lateralis thickness and knee extensor strength in the involved leg increased by 11±5%, 10±6%, and 20±14%, respectively (all P<0.01). Compared to baseline, post-training knee extensor strength symmetry increased from 88±4 to 99±5% (P<0.01) and did not differ from uninjured controls (99±5%, P=0.95). Implementation of BFR exercise at home was feasible, safe and effective. Results extend upon early post-operative application of BFR exercise for ACLR recovery and demonstrate that BFR can improve quadriceps function long after ACLR.
Effects of Chiral Ligands on the Asymmetric Carbonyl-Ene Reaction
Authors: Bakhtiari Atefeh , Safaei-Ghomi Javad 
Published: July 2019

The carbonyl-ene reaction is one of the most well-known reactions for C–C bond formation. Based on frontier molecular orbitals (FMO), carbonyl-ene reactions occur between the highest occupied molecular orbital (HOMO) of the ene compound bearing an active hydrogen atom at the allylic center and the lowest unoccupied molecular orbital (LUMO) of the electron-deficient enophile, which is a carbonyl compound. A high activation barrier enforces the concerted ene reaction rather than a Diels–Alder reaction at high temperature. Employing a catalytic system can eliminate defects in the ene reaction, and chiral catalysts promote the reaction under mild conditions to produce optically active compounds. In this account, we highlight investigations on the effects of various classes of chiral ligands on intermolecular and intramolecular carbonyl-ene reactions.1	Introduction2	Biaryl-Type Chiral Ligands3	C
1- and C
2-Symmetric Bis(oxazoline) Ligands4	Schiff Base Ligands5	N,N′-Dioxide Ligands6	Conclusions
Robotic Systems in Operating Theaters: New Forms of Team–Machine Interaction in Health Care
Authors: Steil Jochen , Finas Dominique , Beck Susanne , Manzeschke Arne , Haux Reinhold 
Published: July 2019

Background Health information systems have developed rapidly and considerably during the last decades, taking advantage of many new technologies. Robots used in operating theaters represent an exceptional example of this trend. Yet, the more these systems are designed to act autonomously and intelligently, the more complex and ethical questions arise about serious implications of how future hybrid clinical team–machine interactions ought to be envisioned, in situations where actions and their decision-making are continuously shared between humans and machines.
Objectives To discuss the many different viewpoints—from surgery, robotics, medical informatics, law, and ethics—that the challenges of novel team–machine interactions raise, together with potential consequences for health information systems, in particular on how to adequately consider what hybrid actions can be specified, and in which sense these do imply a sharing of autonomous decisions between (teams of) humans and machines, with robotic systems in operating theaters as an example.
Results Team–machine interaction and hybrid action of humans and intelligent machines, as is now becoming feasible, will lead to fundamental changes in a wide range of applications, not only in the context of robotic systems in surgical operating theaters. Collaboration of surgical teams in operating theaters as well as the roles, competencies, and responsibilities of humans (health care professionals) and machines (robotic systems) need to be reconsidered. Hospital information systems will in future not only have humans as users, but also provide the ground for actions of intelligent machines.
Conclusions The expected significant changes in the relationship of humans and machines can only be appropriately analyzed and considered by inter- and multidisciplinary collaboration. Fundamentally new approaches are needed to construct the reasonable concepts surrounding hybrid action that will take into account the ascription of responsibility to the radically different types of human versus nonhuman intelligent agents involved.
Is the Expression of the Components of the Carotid Matrix of Rats Influenced by Estrogen, Progestin and Tibolone?
Authors: Steiner Marcelo Luis , Theodoro Thérèse Rachell , Garcia Shirley Gimenez , Mader Ana Maria Amaral Antonio , Pompei Luciano de Melo , Pinhal Maria Aparecida da Silva , Fernandes César Eduardo 
Published: July 2019

Objective To analyze the effects of estrogen alone or in combination with progestogens and tibolone (TIB) on the expression of the extracellular matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9), of perlecan, and of heparanase (HPSE) of the vascular walls of the carotid arteries.
Methods A total of 30 250-day-old ovariectomized Wistar rats were orally treated for 5 weeks with: a) 1 mg/kg of estradiol benzoate (EB); b) EB + 0.2 mg/kg of medroxyprogesterone acetate (MPA); c) EB + 0.2mg/kg of norethisterone acetate (NETA); d) EB + 2 mg/kg of dydrogesterone (DI); e) 1 mg/kg of TIB; f) placebo (CTR). Following treatment, the expression of mRNA for MMP-2, MMP-9, and HPSE was analyzed by real-time polymerase chain-reaction (PCR), and the expression of MMP-2, of MMP-9, of tissue inhibitor of metalloproteinase 2 (TIMP-2), and of perlecan was quantified by immunohistochemistry in the carotid arteries.
Results The groups showed significant differences on mRNA HPSE expression (p = 0.048), which was higher in the EB, EB + MPA, and TIB groups. There was no statistically significant difference in mRNA MMP-2 or MMP-9 expression. The immunohistochemical expression of MMP-2, of TIMP-2, of MMP-9, of HPSE, and of perlecan showed no differences between groups.
Conclusion Estradiol alone or associated with MPA and TIB treatment can increase mRNA HSPE expression of the walls of the carotid arteries in ovariectomized rats.
Temperature and pressure profiles of an ablation-controlled arc plasma in air
Authors: Becerra Marley , Pettersson Jonas , Franke Steffen , Gortschakow Sergey 
Published: July 2019

Abstract
Experimental measurements of the spatial distribution of temperature and composition of ablation-controlled arc plasmas are a key to validate the predictions of metal evaporation and polymer ablation models. Thus, high-speed photography and space-resolved spectroscopic measurements have been performed to characterize a stable air arc plasma jet controlled by ablation of a polymer nozzle made of Polyoxymethylene copolymer (POM-C) or polyamide (PA6). The spectroscopic analysis is performed along a plane perpendicular to the arc jet axis for a current of 1.8 kA, corresponding to an estimated current density of ~65 A mm−2. Temperature and partial pressure profiles of the plasma for copper, hydrogen and carbon in the gas mixture are estimated as an inverse optimization problem by using measured side-on radiance spectra and radiative transfer spectral simulations. It is shown that the generated ablation-controlled arc has a complicated, non-uniform gas composition. Thus, the generated arc jet has a thin metallic core with a lower almost constant hydrogen pressure, surrounded by a thicker hydrogen and carbon mantle at partial pressures slightly lower than atmospheric pressure. The separation of hydrogen and carbon in the core is a consequence of demixing of the polymer vapour in the plasma. It is found that the overall shape of the temperature and pressure profiles obtained for the arc plasmas with the POM-C and PA6 nozzles are similar although differ in peak values and width.
Delta mass shift as a thermometer of kinetic decoupling in Au + Au reactions at 1.23 AGeV
Authors: Reichert Tom , Hillmann Paula , Limphirat Ayut , Herold Christoph , Bleicher Marcus 
Published: July 2019

Abstract
The HADES experiment at GSI will soon provide data on the production and properties of Δ(1232) baryons from Au + Au reactions at 1.23 AGeV. Using the Ultra Relativistic Quantum Molecular Dynamics model, we predict the yield and spectra of Δ(1232) resonances. In addition we show that one expects to observe a mass shift of the Δ(1232) resonance on the order of 50 MeV in the reconstructable Δ(1232) mass distribution. This mass shift can be understood in terms of late stage Δ(1232) formation with limited kinetic energy. We show how the mass shift can be used to constrain the kinetic decoupling temperature of the system.
Detection of body noise with an ultra-sensitive SQUID system
Authors: Storm J-H , Hömmen P , Höfner N , Körber R 
Published: July 2019

Abstract
Using an ultra-sensitive single-channel SQUID system an upper limit of 80 aT Hz−1/2 for the body noise contribution of the human head in ultra-low-field SQUID-based MRI or MEG is determined. We discuss in detail the various noise contributions which need to be taken into account. Simulations and measurements of conducting phantoms show that presumably residual radio frequency interference cause an increase in the sensor noise at the aT Hz−1/2-level and need to be considered. Using a phenomenological approach, the body noise contribution of the human head is determined to 55 aT Hz−1/2 for our setup. We also provide simulations of the expected body noise for other sensor geometries.
Pellet fueling experiments in Wendelstein 7-X
Authors: Baldzuhn J , Damm H , Beidler C D , McCarthy K , Panadero N , Biedermann C , Bozhenkov S A , Brunner K J , Fuchert G , Kazakov Y , Beurskens M , Dibon M , Geiger J , Grulke O , Höfel U , Klinger T , Köchl F , Knauer J , Kocsis G , Kornejew P , Lang P T , Langenberg A , Laqua H , Pablant N A , Pasch E , Pedersen T S , Ploeckl B , Rahbarnia K , Schlisio G , Scott E R , Stange T , von Stechow A , Szepesi T , Turkin Y , Wagner F , Winters V , Wurden G , Zhang D 
Published: July 2019

Abstract
During the two most recent experimental campaigns in the advanced stellarator Wendelstein 7-X (W7-X) (Klinger et al 2017 Plasma Phys. Control. Fusion
59 014018; Bosch et al 2017 Nucl. Fusion
57 116015; Wolf et al 2017 Nucl. Fusion
57 102020; Pedersen et al 2017 Phys. Plasmas
24 0555030) hydrogen ice pellet injection was performed for the first time. In order to investigate the potential of pellet fueling in W7-X and to study the particle deposition in a large stellarator, a blower-gun system was installed with 40 pellets capability. The experience gained with this system will be used for the specification of a future steady-state pellet injector system. One important motivation for a pellet injector (Dibon 2014 Master-Thesis Technical University Munich, Max-Planck Institut IPP) on W7-X is the mitigation of hollow density profiles expected in case of predominant neoclassical transport. For long-pulse operation of up to 30 min, only electron cyclotron resonance heating is available on W7-X. Hence, pellet injection will be the only source for deep particle fueling. Deep particle fueling by pellets in tokamaks is supported by a grad-B drift, if the pellets are injected from the magnetic high-field-side. This approach was tested in W7-X, as well. The injection of series of pellets was also tested. Here, deep fueling is supported for later pellets in the series by the plasma cooling following the initial pellets in the same series. As in earlier experiments in the heliotron LHD (Takeiri et al 2017 Nucl. Fusion
57 102023), deep and rapid fueling could be achieved successfully in W7-X.
Andreev reflections modulated by the breaking of space-inversion symmetry in graphene-typed materials
Authors: Li Xue-Si , Zhang Shu-Feng , Gong Wei-Jiang 
Published: July 2019

Abstract
We theoretically perform a comprehensive analysis about the influences of the space-inversion symmetry breaking in graphene-based materials on the Andreev reflections (AR) in the normal-metal/superconductor (NS) and NSN heterojunctions. It is found that in the NS junction, the AR can be suppressed or be enhanced by the enhancement of space-inversion symmetry breaking, depending on the relationship among the coherence parameters. Following this result, the AR properties in the NSN structure are evaluated. It is readily observed that the local AR can be weakened for low space-inversion symmetry breaking, and can be enhanced for high space-inversion symmetry breaking. Alternatively, the efficiency of the crossed AR can be improved to a great degree, with the increase of space-inversion symmetry breaking. One can therefore understand the special role of space-inversion symmetry in modulating the AR, especially for the enhancement of crossed AR.
Development of a steepest-descent control solution for Multi-Input Multi-Output swept sine testing in a
virtual shaker environment
Authors: Musella U , Waimer S , Peeters B , Marulo F , Guillaume P 
Published: July 2019

Abstract
Multiple-Input Multiple-Output (MIMO) sine sweep is nowadays acknowledged to be one of the best excitation techniques for the modal testing of large aerospace structures, being an optimal solution in the tradeoff between high-quality FRFs testing time. Due to the test levels that can be reached during the sine sweeps and the increasing complexity and cost of the test articles, monitoring the recordings of multiple transducers translates in the actual need of guaranteeing that the responses are controlled on-line to a (safe) reference level. The development of a dedicated MIMO control strategy is very challenging, especially as a consequence of the transient behavior of the sweeps. This work proposes to investigate a solution for the on-line control of a MIMO continuous swept sine test combining the harmonic estimator with a steepest descent feedback control, typically adopted for the cancellation of tonal disturbances. The controller is developed in a virtual shaker testing environment, in order to tackle, already in the development stage, the effects that can be encountered during an actual test and that cannot be modeled with a linear system identification.
Blast Load Analysis and Simulation of Unreinforced Concrete Masonry
Authors: Tan Warren Antonio , Tingatinga Eric Augustus , Alvarez Victoria 
Published: July 2019

Abstract
This study presents an innovative blast analysis tool that can be used in assessing blast performance of concrete masonry walls. The analysis tool proposes a structural model of unreinforced masonry (URM) walls, and a simplified procedure to generate load histories on structures subjected to blast loading. This study focuses on hollow concrete masonry units (CMU) walls. Three-dimensional masonry walls are modeled using discrete rigid bodies connected by nonlinear springs. Connections between two masonry blocks attached by mortar joint are modeled by treating adjoining springs as springs in series. The blast load histories are calculated using UFC 3-340-02. The proposed tool generates individual load-time histories for each discrete elements of a wall. The individual load-time histories, and the peak pressure distribution on a wall surface, are compared to experimental measurements to validate the blast-load-generating algorithm. The two modules (blast-load, and numerical model generator) are then used to simulate an actual experiment on URM wall for validation. For this study, experiments on URM wall arching is simulated. The proposed tool is able to approximate the wall response, particularly, the maximum positive and negative displacements. The good agreement proved the applicability of the proposed analysis tool to the analysis of URM walls.
Energy Harvesting from Two Coupled Beams with Piezoelectic Patches
Authors: Belmokhtar M , Ghandchi Tehrani M , Ture Savadkoohi A , Lamarque C-H 
Published: July 2019

Abstract
This paper presents the problem of energy harvesting from two coupled beams using piezoelectric patches. The energy harvester is subject to both harmonic and random excitation. The voltages across the piezoelectric patches are measured in real time in order to calculate the power. The coupling between the beams is an important factor for harvesting energy for a wider frequency band because new modes appear with this effect. This would result in widening the frequency bandwidth in which the energy can be harvested. Both numerical and analytical models are developed for the two coupled beams with two different lengths. The natural frequencies and mode shapes are derived and the harvested power is calculated for the random excitation. The resistance of the two piezoelectric patches is varied and the optimum resistance is derived. Experiments are carried out on two coupled beams to obtain the performance of the harvester to demonstrates the increase of the frequency bandwidth in which the energy can be harvested. It is shown that the harvester can collect energy at a wider frequency bandwidth compared to a single beam.
Wave dispersion curves in discrete lattices derived through asymptotic multi-scale method
Authors: Rallu Antoine , Boutin Claude , Hans Stéphane 
Published: July 2019

Abstract
This paper falls within the study of dispersion feature of elastic periodic media. In most cases, no analytic description is reachable and the problem is solved via numerical computations of the dispersion curves.We propose in this paper an analytic method dedicated to lattice systems that enables to reconstruct part by part the dispersion curves via an asymptotic multi-scale method. This method is illustrated on periodic reticulated beams. At low frequency, when there is a large scale separation between the length of the cell and the characteristic size of the vibrations, the classical homogenization method allows efficiently to establish the continuous equivalent dynamic description and the associated wave propagation properties. This scale separation is lost for frequencies of the order or higher than the diffraction frequency. However, instead of considering the amplitude of the mean displacement in a unit cell, the concept of scale separation can still be used by considering the amplitude of periodic eigenmodes defined on (multi-)cells. Thus, similar principles of asymptotic multi-scale method enables to describe the large scale modulations around the eigenfrequencies of the mono-and/or multi-cells period. Finally, the properties of the modulation are straightforwardly related to the dispersion curves at the considered frequencies.
Numerical investigation of the potential of tailored inclusions as noise reduction measures
Authors: Mittermeier F , Schauer J , Miksch M , Müller G 
Published: July 2019

Abstract
The reduction of noise and vibrations is an important task in automotive and aircraft industry. Various applications require slender or adjustable reduction measures. Metamaterials formed by a periodic assembly of unit cells consisting of non-homogeneous material decomposition and having topology dependent favorable absorption properties can meet this need. The absorption efficiency of different types of metamaterials has already been proven by various authors. Thereby metamaterials formed by a periodic assembly of tuned mass dampers on plate-like structures or porous layers with rigid inclusions have been investigated. Beyond that, we suggest to design metamaterials consisting of inclusions containing appropriately tuned mass dampers embedded in a material layer and to examine their noise reduction potential. It is investigated, whether besides absorbing energy by exciting the damping device, the orientation of the tuned mass damper is active by purposefully deflecting waves inside the structure. The analysis is carried out applying the Wave Finite Element Method. Using the inverse approach of the Wave Finite Element Method, stop bands, i.e. frequencies for which no free wave propagation is observed, are detected. In a parameter study, the influence of the characteristics of the inclusion on the absorption behavior of the metamaterial is determined.
Parametric model order reduction for acoustic metamaterials based on local thickness variations
Authors: Aumann Q , Miksch M , Müller G 
Published: July 2019

Abstract
The use of lightweight materials is obligatory in the design of economic structures, but with decreasing mass, the vibro-acoustic properties of the structures become unfavorable. Acoustic metamaterials based on the concept of acoustic black holes (ABH) can improve the vibrational behavior by adding local thickness variations to the host structure. To make computational models of metamaterials also valid for high frequencies, a fine discretization has to be used. This leads to high computation times. A parametric model order reduction (PMOR) approach is presented, which is able to create an efficient reduced model of ABHs. In the first step, one structure preserving reduced model for each parameter is generated using the iterative rational Krylov algorithm (IRKA). The transfer functions of all reduced models are used in the second step to create a single parametric model using the Loewner framework. The resulting model can be used to efficiently evaluate the frequency response of a structure equipped with ABHs for different parameter sets.