bluuebunny/crossref_metadata_2025 huggingface dataset:
On the edge element boundary element method/finite element method coupling for time harmonic electromagnetic scattering problems
Authors: Dodig Hrvoje , Poljak Dragan , Cvetković Mario
Published: April 2021

Over recent decades coupled MoM/FEM formulation emerged as dominant method for solving EM scattering problems over inhomogeneous domains. Initial efforts on coupling of edge element BEM with edge element FEM have lost momentum and somehow disappeared from recent literature, possibly because of mathematical and other issues. This article, however, presents correct coupling of edge element BEM with edge element FEM. Such coupling is convenient because edge basis functions are used for modeling both the surface and the interior of the problem. We show that singularity extraction is simpler when compared with singularity extraction in MoM/FEM. Because BEM part of edge element BEM/FEM formulation uses simpler Green's function, the method is easier to implement than MoM/FEM which uses Dyadic Green's functions. The accuracy of the method is demonstrated by comparison with Mie series and with MoM/FEM and MoM/VSIE methods. Convergence of the method with respect to number of surface and interior edges was investigated by comparing 20 computational models with Mie series. Computational results suggest that edge‐element BEM/FEM performs well for scattering problems involving objects with sharp corners. Finally, the ability of the method to cope with relatively large number of elements was demonstrated on the example of human head illuminated by 3.5 GHz EM plane wave.
Graduate programs admissions: the whole person approach
Authors: Barksdale W. Kevin
Published: April 2021

The October 2020 issue featured commentary from Dr. Guillermo Prado, Vice Provost of Academic Affairs and Dean of the Graduate School at the University of Miami. He suggested the GMAT and GRE should be dropped as a graduate admission requirement to improve program and campus diversity. Dr. Prado ushered in a new season at the University of Miami this past fall without standardized tests in graduate programs after extensive planning. I extend his commentary and offer a “whole person approach” to admissions.
Spring cleaning: Review and (re)organize your marketing materials and space
Authors: Talarico Donna
Published: April 2021

When I worked in tech school admissions in the early 2000s, my director would set aside a day at least once a year for office organizing. We'd dress down, order pizza, and get to work. As part of this, we also usually rearranged our “cubbies” (a term of endearment for our small, square, sans‐door offices). Moving my desk, small bookcase, and two visitor chairs — coupled with a thorough cleaning of drawers and surfaces — gave me a sense of accomplishment. As an admissions team, together, we always felt reignited.
Improving Iris Recognition with Liquid Lens Technology
Authors: Berthelon Xavier
Published: April 2021

Iris identification and verification systems have become one of the most accurate biometric modalities due to the iris's unique and distinguishable features. Technical advances have significantly reduced the cost and size of these systems, leading to an increase in the value proposition for several industries. Image resolution and quality of focus are essential in deciphering the complex texture of the iris. Conventional iris recognition devices require bulky and high‐cost systems to overcome the optical constraints of mechanical lens‐based cameras. This paper describes how the use of a liquid lens device can overcome the optical limitations of traditional systems, leading to a low‐cost, smaller, and faster system.
Talking About a Revolution: From Quantum Mechanics to Quantum Technologies
Authors: Ritter Stephan
Published: April 2021

Quantum physics is often considered weird, counterintuitive, and irrelevant at macroscopic scales – something for physicists and other nerds. And yet, more and more people talk about it publicly, including politicians like Canadian Prime Minister Justin Trudeau and German chancellor Angela Merkel. What has happened? Why is a theory that is about a century old suddenly in vogue when it is combined with the word technology? And why are people talking about a second quantum revolution?
Cost‐Effective Production of Integrated Monolithic Sensor Packages
Authors: Zuehlke Hans‐Ulrich , Gebhardt Mandy
Published: April 2021

The growth of the magnetic sensor market is driven by position, speed and angle sensing needs across consumer and industrial applications. Thermal annealing has been used to maximize the magnetoresistance effects of magnetic sensors, but requires multiple steps to produce sensors with different magnetic orientations. This article gives an overview of a new selective laser annealing approach that provides several advantages over thermal annealing, such as enabling smaller magnetic device structures, reducing process steps and simplifying magnetic sensor manufacturing.
The Role of Adaptive Vision AI in Autonomous Machine Vision
Authors: Hyatt Yonatan
Published: April 2021

American singer‐songwriter Woody Guthrie once said that any fool can make something complicated, but it takes a genius to make it simple. This is the philosophy that guided the team at Inspekto to create adaptive vision AI (AV‐AI), the technology at the core of the company's solutions. AV‐AI technology merges three different AI‐based engines to deliver the most autonomous vision inspection systems currently on the market.
Surface Topography Measurement
Authors: Tan Özgür , Reiff Ellen‐Christine
Published: April 2021

When testing the surface quality of the finest structures, white‐light interferometers are in their element, both in production and development, as well as in laboratories and research. This measurement principle works on almost all materials, operates without contact, providing surface profiles in 3D with height resolutions in the nanometer range. Today, large‐area measurements are just as possible as detailed investigations with high lateral resolution, e.g. for surface characterization of wafers, optical components or in tribology.
Epitaxial Growth and Solar‐Blind Photoelectric Characteristic of Ga2O3 Film on Various Oriented Sapphire Substrates by Plasma‐Enhanced Chemical Vapor Deposition
Authors: Hu Haizheng , Wu Chao , Zhao Nie , Zhu Zhiyan , Li Peigang , Wang Shunli , Tang Weihua , Guo Daoyou
Published: April 2021

The epitaxial growth of Ga2O3 thin films is important for their applications in electronic and optoelectronic devices. Herein, the growth of Ga2O3 thin films on various oriented (c‐, a‐, m‐, r‐plane) sapphire substrates by plasma‐enhanced chemical vapor deposition (PECVD) is investigated using high purity metallic Ga and oxygen (O2) as precursor materials and argon (Ar) as carrier gas under a relatively lower growth temperature compared with other CVD methods. The effects of the substrates orientation to the surface morphology, crystal orientation, growth rate, optical properties, and solar‐blind photoelectric properties of Ga2O3 thin films are studied. The epitaxial film grown on the c‐plane sapphire substrate exhibits the best crystallinity and smooth surface, while that grown on the r‐plane shows the fastest growth rate of 1.97 μm h−1. The photodetector based on the Ga2O3 film grown on the c‐plane exhibits the lowest dark current of 0.17 nA, the highest Ilight/Idark ratio of 242.47, and the fastest response time of 0.31 s, while that of grown on the m‐plane shows the highest responsivity (Rλ) of 27.71 mA W−1.
A new robotically assisted system for total knee arthroplasty: A sheep model study
Authors: Chen Xin , Li Zheng , Zhang Xiaofeng , Yan Jun , Ding Lele , Song Youdong , Huo Yujia , Chan Matthew T.V. , Wu William K.K. , Lin Jin
Published: April 2021

Background

We investigated the accuracy and safety of a new HURWA robotic‐assisted total knee arthroplasty (TKA) system in a sheep model.

Methods

Ten male small‐tailed Han sheep were used in this study. Sheep were imaged by computed tomography scan before and after bone resection and the cutting errors between actual bone preparation and preoperative planning of the femur and tibia in three dimensions were measured.

Results

The overall accuracies after surgery compared with that from preoperative surgical planning of the left and right femurs were 1.93 ± 1.02° and 1.93 ± 1.23°, respectively. Additionally, similarly high overall accuracies for the left and right tibia of 1.26 ± 1.04 and 1.68 ± 0.92°, respectively, were obtained. The gap distances of the distal cut, anterior chamfer, anterior cut, posterior chamfer and posterior cut on the medial side were 0.47 ± 0.35 mm, 0.41 ± 0.37 mm, 0.12 ± 0.26 mm, 0.41 ± 0.44 mm and 0.12 ± 0.23 mm, respectively. No intraoperative complications, such as intraoperative fracture, massive bleeding or death, occurred.

Conclusion

This new HURWA robotic‐assisted TKA system is an accurate and safe tool for TKA surgery based on the sheep model.
Periodic event‐triggered control for incrementally quadratic nonlinear systems
Authors: Xu Xiangru , Tahir Adam M. , Açıkmeşe Behçet
Published: April 2021

Periodic event‐triggered control (PETC) evaluates triggering conditions only at periodic sampling times, based on which it is decided whether the controller needs to be updated. This article investigates the global stabilization of nonlinear systems that are affected by external disturbances under PETC mechanisms. Sufficient conditions are provided to ensure the resulting closed‐loop system is input‐to‐state stable (ISS) for the state feedback and the observer‐based output feedback configurations separately. The sampling period and the triggering functions are chosen such that the ISS‐Lyapunov function of continuous dynamics is also the ISS‐Lyapunov function of the overall system. Based on that, sufficient conditions in the form of linear matrix inequalities are provided for the PETC design of incrementally quadratic nonlinear systems. Two simulation examples are provided to illustrate the effectiveness of the proposed method.
Polybromides of Transition Metal Chelates – Synthesis, Structure and Spectral Properties
Authors: Babu Ramavath , Bhargavi Govindugari , Rajasekharan Melath V.
Published: April 2021

Five new polybromide compounds containing tris‐chelates of 1,10‐phenanthroline and 2,2‐bipyridine as counter cations are described: [Mn(phen)3](Br3)2 (1), [Co(phen)3](Br3)3 (3) and [M(phen)3](Br3)(Br8)1/2 where, M=Fe (2), Cu(4) or Zn(5). All are obtained by self assembly in solution starting from divalent transition metal bromides and bromine along with the ligand. In the case of CoBr2, bromine acts as a tribromide precursor as well as oxidising agent. The Mn compound is isomorphous with the corresponding triodide and analogously contains one short and one normal trihalide ion. The Co compound contains one bent but symmetric Br3− ion. The three compounds containing the Z‐shaped octabromide ion are isostructural. While the cation in 1 has a crystallographically imposed C3 symmetry, the tris chelates in the other four compounds have near trigonal symmetry. Unusually, the trigonally compressed octahedral cation in 4 has six almost equal Cu−N bond distances. Attempts to prepare bpy analogs of 1 resulted in a new dibromo‐bridged compound [Mn2Br2(bpy)4](Br3)2 (6) and a dioxo‐bridged compound [Mn2O2(bpy)4](Br3)3 (7). The mixed valence cation in 7 formed by bromine oxidation of MnBr2, followed by disproportionation, is well known with other anions. All the paramagnetic compounds (1, 4, 6, 7) give resolved EPR spectra since the bulky anions help to magnetically isolate the cations. The unsymmetric dibromo bridges in 6 produce a net, albeit weak, ferromagnetic coupling between the two [Mn(bpy)2]2+ fragments. Raman as well as electronic spectra are reported for all compounds. Raman bands, though significantly different even for isostructural compounds, may be understood in terms of Br3− ions and Br2 molecules. All compounds give luminescence from phen and bpy both in solid and solution states, modulated by the coordinated metal ions.
Phytochemical‐Assisted Synthesis of Cuprous Oxide Nanoparticles and Their Antimicrobial Studies
Authors: Mannarmannan Meenakshi , Biswas Krishnendu
Published: April 2021

Cuprous oxide (Cu2O) nanoparticles (Nps) were synthesized using the vegetable waste viz. Daucus carota (Carrot) peel and agro wastes Cocos nucifera (Coconut) husk and Artocarpus heterophyllus (Jackfruit) seed. X‐ray diffraction analysis confirmed the formation of cubic Cu2O nanoparticles having high crystallinity. Microscopy analysis of the synthesized Cu2O nanoparticles using D. carota and A. heterophyllus revealed spheroidal‐like cluster formation, whereas rice spikelet nanostructures were observed in the case of C. nucifera synthesized Cu2O Nps. Energy‐dispersive X‐ray spectra of all the nanoparticles showed the presence of Cu and Oin the desired ratio, confirming the stoichiometry. Fourier transform infrared spectra revealed the presence of the functional groups responsible for the synthesis of the nanoparticles. The antimicrobial activity studies of the synthesized Cu2O nanostructures showed satisfactory results against the bacterial and fungal species. Hence the vegetable and agro‐waste may be regarded as a biofactory for synthesizing the Cu2O nanoparticles.
Pillar[n]arene Derivatives as Sensors for Amino Acids
Authors: Joseph Roymon
Published: April 2021

Owing to the involvement in various biological processes, developing sensors for the detection of amino acids is an important area of research. Pillar[n]arenes are elegant macrocyclic systems that have been used as potential host systems for various applications including the sensing of ions and molecules. Since its inclusion in 2008, pillar[n]arenes and its derivatives have received much attention among the researchers, and these molecular systems are used as excellent host systems for the formation of inclusion complexes with various guest molecules which have relevance both in chemistry and biology. Herein, we highlight the recent developments on the sensing of amino acids by pillar[n]arene derivatives. The majority of the sensors we discussed here detect amino acids by fluorescence techniques and their sensing was further supported by various other spectroscopic methods. In some cases sensing was achieved visually by the change in colour of the host system upon interaction with the amino acids.
Metal Mediated Synthesis of 2‐thiazolines: Access to Regio‐ and StereoselectiveN,S‐heterocycles
Authors: Popy Dilruba A.
Published: April 2021

2‐thiazolines are very important structural motifs in pharmaceuticals, agrochemicals and in chemistry. Due to their extensive applications, synthesis of these molecules has been investigated widely in recent years. Despite the progress in these areas, the development of efficient methodologies to synthesize such type of molecules, avoiding the use of relatively expensive and/or toxic reagents, harsh reaction conditions and low yields of products, are in high demand. Transition‐metal catalysts played significant roles to meet these challenges in past few decades to synthesize stereochemically importantN‐heterocycles. This mini review focuses on the metal mediated synthetic strategies and challenges of 2‐thiazolines. It was found that most of these protocols involved the formation of both C−N and C−S bonds and the major challenges were the stereochemistry at C‐4 position and C(2)‐exomethine position. Moreover, the development of asymmetric processes was completely overlooked. Here, the reaction scopes, limitations, mechanistic overview and future prospects are also discussed.
Direct Quantification of Mixed Organic Acids Based on Spectral Image with Deep Learning
Authors: Wang Wenjing , Luo Run , Duan Qiannan , Feng Yunjin , Chen Jiayuan , Huang Yicai , Bi Sifan , Liu Fenli , Lee Jianchao
Published: April 2021

Identification of organic acid is crucial indicator for field of environment, healthcare and industry, which involves the time‐consuming and labor‐intensive progress. The simultaneous detection for complex mixture becomes a new target when large‐scale instruments is the mainstream measurement approach. With the burst development of machine learning in solving complex problem, the progress is being made for quick detection of mixtures. The next challenge is to provide sufficient data to satisfy the need of algorithm. In this work, we proposed the modified spectrometer technology combined with the deep learning to quantify the mixed organic acids. Organic acids interact with light in the various background to map the information in the form of images. Deep learning could establish the relationship between images and concentrations. According to the result, trained convolutional neural network could achieve the goal of simultaneous measurement of organic acids, which speeds up the implementation in the parallel detection and suggests new twists in the field of chemistry.
Effect of the Oxygen Vacancies in CeO2 by the Ce3+ Incorporation to Enhance the Photocatalytic Mineralization of Phenol
Authors: Méndez‐Salazar Sandra , Aguilar‐Martínez Octavio , Piña‐Pérez Yanet , Pérez‐Hernández Raúl , Santolalla‐Vargas Carlos E. , Gómez Ricardo , Tzompantzi Francisco
Published: April 2021

In this paper, the phenol mineralization by Ce3+‐doped CeO2 by photocatalysis at room temperature, is shown for the first time. The photocatalytic behavior of CeO2 was improved through the incorporation of Ce3+ into its crystalline lattice. The materials were prepared by the precipitation method at low temperatures varying the Ce4+:Ce3+ molar ratio of the precursors during the synthesis process. It is worth noting that, the synthesized photocatalysts did not carry out a thermal treatment after their preparation. The results obtained from Raman analysis demonstrated the formation of oxygen vacancies by the incorporation of Ce3+. The improvement of the photocatalytic activity was attributed to an optimal content of Ce3+ which promoted structural defects (such as oxygen vacancies). Radical species, such as O2.−, are mainly formed during the photocatalytic process, which are probably the main responsible for inducing the mineralization process of the studied pollutant.
Sulfur Catalyzed Metal‐ and Solvent‐Free ABB'C Four‐Component Synthesis of N‐Arylidene‐2‐aryl‐imidazo[1‐2‐a]azin‐3‐amines via Strecker Reaction
Authors: Pavithra Thangavel , Devi E. Sankari , Nagarajan Subbiah , Sridharan Vellaisamy , Maheswari C. Uma
Published: April 2021

An efficient ABB'C four‐component Strecker reaction between 2‐aminopyridines, aromatic aldehydes and trimethylsilyl cyanide (TMSCN) was developed under metal‐ and solvent‐free conditions to access N‐arylidene‐2‐aryl‐imidazo[1,2‐a]azin‐3‐amines in high yields. This one‐pot reaction was carried out in the presence of elemental sulfur as catalyst using readily available starting material at room temperature. The reaction was tolerant to several substituted 2‐aminopyridines and aryl aldehydes and have good green chemistry metrics as compared to the reported methods.
Covalent Immobilization of Candida antarctica Lipase B on Functionalized Hollow Mesoporous Silica Nanoparticles
Authors: Zhong Lijuan , He Caiyun , Xiao Chunyan , Yao Chuanyi , Pyatt Ian Howard , Lu Yinghua
Published: April 2021

Candida antarctica lipase B (CALB) produced by recombinant Pichia pastoris was covalently immobilized to a carboxyl‐functionalized hollow mesoporous silica sphere (HMS) synthesized by sol‐gel precipitation. The HMS was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffractometer (XRD), and Brunauer‐Emmett‐Teller (BET). The immobilized CALB was characterized through Fourier transform infrared spectra (FT‐IR) and elemental analysis to verify the binding of enzyme. The free and immobilized CALB were tested in tributyrin hydrolysis. Results revealed that CALB loading capacity of HMS‐COOH was about 28.6 mg/g support and the corresponding enzyme activity was up to about 2700 U/g support at optimal pH and temperature, which was 6.5 and 30 °C respectively. Moreover, compared with free CALB, the immobilized CALB presented more resistant towards the reaction pH and temperature changes. Furthermore, the immobilized CALB retained 60 % residual activity after eight batches of recycling and exhibited better thermal stability and storage stability, which was promising in the potential industrial applications.
Mapping Spatial Genetic Landscapes in Tissue Sections through Microscale Integration of Sampling Methodology into Genomic Workflows
Authors: Voith von Voithenberg Lena , Kashyap Aditya , Opitz Lennart , Aquino Catharine , Sykes Timothy , Nieser Maike , Petrini Lorenzo F. T. , Enrriquez Casimiro Nadia , van Kooten Xander F. , Biskup Saskia , Schlapbach Ralph , Schraml Peter , Kaigala Govind V.
Published: April 2021

In cancer research, genomic profiles are often extracted from homogenized macrodissections of tissues, with the histological context lost and a large fraction of material underutilized. Pertinently, the spatial genomic landscape provides critical complementary information in deciphering disease heterogeneity and progression. Microscale sampling methods such as microdissection to obtain such information are often destructive to a sizeable fraction of the biopsy sample, thus showing limited multiplexability and adaptability to different assays. A modular microfluidic technology is here implemented to recover cells at the microscale from tumor tissue sections, with minimal disruption of unsampled areas and tailored to interface with genome profiling workflows, which is directed here toward evaluating intratumoral genomic heterogeneity. The integrated workflow—GeneScape—is used to evaluate heterogeneity in a metastatic mammary carcinoma, showing distinct single nucleotide variants and copy number variations in different tumor tissue regions, suggesting the polyclonal origin of the metastasis as well as development driven by multiple location‐specific drivers.
Zooming Into Summer: Key Takeaways From a Virtual Summer Reading Intervention
Authors: Washburn Erin K. , Beach Kristen D. , Gesel Samantha A. , Billingsley MaryCatherine , Howard Chelsea , King BreAnn , Vintinner Jean Payne
Published: April 2021

The aim of this teaching tip is to share four key takeaways from virtual implementation of a reading intervention in a four‐week summer reading camp (SRC) for rising second‐ and third‐grade students in need of foundational skills support. The SRC, which was a partnership between a university and school district, pivoted to a virtual format for summer 2020 as a result of the COVID‐19 global pandemic. Through information collected during SRC observations and a series of semistructured focus group interviews with SRC teachers, staff, and participating families, the authors found: (a) connecting with families is fundamental, (b) creating a positive virtual learning space is essential, (c) methods and materials for virtual learning matter, and (d) the learning curve for virtual teaching needs ongoing support. Details and ideas are shared for each takeaway with the goal of supporting educators with virtual implementation of reading intervention.
Erratum to: Mass Unspecific Supervised Tagging (MUST) for boosted jets
Authors: Aguilar-Saavedra J. A. , Joaquim F. R. , Seabra J. F.
Published: April 2021

Because of an error in the production stage, the same figure was repeated throughout the paper. The originally published wrong file has been replaced online.
The Stieltjes condition and multidimensional $${\mathcal {K}}$$-moment problems
Authors: Schmüdgen Konrad
Published: April 2021

We prove a solvability theorem for the Stieltjes problem on $$\mathbb {R}^d$$

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which is based on the multivariate Stieltjes condition $$\sum _{n=1}^\infty L(x_j^{n})^{-1/(2n)} =+\infty $$

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This result is applied to derive a new solvability theorem for the moment problem on unbounded semi-algebraic subsets of $$\mathbb {R}^d$$

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Erfassung der Labortestungen auf SARS-CoV-2 in Deutschland
Authors: Seifried Janna , Hoffmann Alexandra , Reda Sarah , Böttcher Sindy , Abu Sin Muna , Hofmann Alexandra , Noll Ines , von Laer Anja , Reuss Annicka , Oh Djin-Ye , Albrecht Stefan , Stern Daniel , Willrich Niklas , Staat Doreen , Zacher Benedikt , Schneider Marc , Feig Marcel , Nitsche Andreas , Rieck Thorsten , Rexroth Ute , Eckmanns Tim , Hamouda Osamah
Published: April 2021

Die Erfassung von Daten zu SARS-CoV-2-Testungen in Deutschland sind für die Einschätzung des Infektionsgeschehens im Rahmen der COVID-19-Pandemie von zentraler Bedeutung. Am Robert Koch-Institut (RKI) werden dazu die Daten aus verschiedenen Systemen zur Erfassung von Labortestungen zusammengeführt. In diesem Beitrag werden zunächst bedeutsame Aspekte der Testverfahren erläutert. Nachfolgend werden die unterschiedlichen Systeme zur Erfassung von Labortestungen erläutert und Testzahlen aus der RKI-Testlaborabfrage und der laborbasierten Surveillance SARS-CoV‑2 sowie die Abrechnungsdaten der kassenärztlichen Vereinigungen zu SARS-CoV-2-Labortestungen dargestellt.

Mit der RKI-Testlaborabfrage und der laborbasierten Surveillance SARS-CoV‑2 stand früh in der Pandemie eine Surveillance zur Verfügung, mit der unter den teilnehmenden Laboren Daten zu durchgeführten Testungen und Testkapazitäten ausgewertet werden können. Durch die Erfassung von positiven und negativen Testergebnissen sind Aussagen zur Gesamtzahl der durchgeführten Testungen sowie dem Anteil der positiven Testergebnisse möglich. Während die aggregierten Testzahlen bundesweit weitestgehend repräsentativ sind, ist die Repräsentativität auf Bundesland- und Landkreisebene aber nicht immer gegeben. Die Abrechnungsdaten der Kassenärztlichen Vereinigungen können die Labordaten im Nachhinein ergänzen. Sie erlauben eine retrospektive Einschätzung der Gesamtzahl von SARS-CoV-2-Tests in Deutschland, da die Leistungen der vertragsärztlichen Versorgung aller gesetzlich Krankenversicherten (ca. 85 % der Bevölkerung) enthalten sind.

Die verschiedenen Systeme zur Erfassung von Labortestungen ergänzen sich gegenseitig. Die Auswertungen fließen in die Maßnahmenempfehlungen zur Pandemiebewältigung ein.
Inferring Switched Nonlinear DynamicalSystems
Authors: Jin Xiangyu , An Jie , Zhan Bohua , Zhan Naijun , Zhang Miaomiao
Published: April 2021

Identification of dynamical and hybrid systems using trajectory data is an important way to construct models for complex systems where derivation from first principles is too difficult. In this paper, we study the identification problem for switched dynamical systems with polynomial ODEs. This is a difficult problem as it combines estimating coefficients for nonlinear dynamics and determining boundaries between modes. We propose two different algorithms for this problem, depending on whether to perform prior segmentation of trajectories. For methods with prior segmentation, we present a heuristic segmentation algorithm and a way to classify themodes using clustering. Formethods without prior segmentation, we extend identification techniques for piecewise affine models to our problem. To estimate derivatives along the given trajectories, we use Linear MultistepMethods. Finally, we propose a way to evaluate an identified model by computing a relative difference between the predicted and actual derivatives. Based on this evaluation method, we perform experiments on five switched dynamical systems with different parameters, for a total of twenty cases. We also compare with three baseline methods: clustering with DBSCAN, standard optimization methods in SciPy and identification of ARX models in Matlab, as well as with state-of-the-art identification method for piecewise affine models. The experiments show that our two methods perform better across a wide range of situations.
Improving insulin sensitivity, liver steatosis and fibrosis in type 2 diabetes by a food-based digital education-assisted lifestyle intervention program: a feasibility study
Authors: Zaharia Oana P. , Kupriyanova Yuliya , Karusheva Yanislava , Markgraf Daniel F. , Kantartzis Konstantinos , Birkenfeld Andreas L. , Trenell Michael , Sahasranaman Aarti , Cheyette Chris , Kössler Theresa , Bódis Kálmán , Burkart Volker , Hwang Jong-Hee , Roden Michael , Szendroedi Julia , Pesta Dominik H.
Published: April 2021

Purpose

Recent trials demonstrated remission of type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) following formula diet-induced weight loss. To improve the outreach for populations in need, many mobile health apps targeting weight loss have been developed with limited scientific evaluation of these apps. The present feasibility study investigated the effects of a novel approach incorporating a regular ‘whole food-based’ low-calorie diet combined with app-based digital education and behavioral change program on glucose metabolism and disease management.

Methods

Twenty-four individuals with type 2 diabetes followed this approach supported by weekly coaching calls for 12 weeks. Phenotyping included bioimpedance analysis, mixed-meal tolerance test, magnetic resonance spectroscopy and transient elastography for assessing liver fat content and liver stiffness.

Results

Over 12 weeks, participants reduced their body weight by 9% (97 ± 13 to 88 ± 12 kg), body mass index (BMI; 33 ± 5 to 29 ± 4 kg/m2), total fat mass (31 ± 10 to 27 ± 10%) (all p < 0.01) and liver fat by 50% alongside with decreased liver stiffness. Target HbA1c (< 6.5%) was achieved by 38% and resolution of NAFLD (liver fat content < 5.6%) was observed in 30% of the participants.

Conclusion

This novel approach combining digital education with a low-calorie diet results in effective improvements of body weight, glycemic control and NAFLD and could complement existing care for patients with type 2 diabetes.

Trial registration

NCT04509245
Pseudoinverse graph convolutional networks
Authors: Alfke Dominik , Stoll Martin
Published: April 2021

Graph Convolutional Networks (GCNs) have proven to be successful tools for semi-supervised classification on graph-based datasets. We propose a new GCN variant whose three-part filter space is targeted at dense graphs. Our examples include graphs generated from 3D point clouds with an increased focus on non-local information, as well as hypergraphs based on categorical data of real-world problems. These graphs differ from the common sparse benchmark graphs in terms of the spectral properties of their graph Laplacian. Most notably we observe large eigengaps, which are unfavorable for popular existing GCN architectures. Our method overcomes these issues by utilizing the pseudoinverse of the Laplacian. Another key ingredient is a low-rank approximation of the convolutional matrix, ensuring computational efficiency and increasing accuracy at the same time. We outline how the necessary eigeninformation can be computed efficiently in each applications and discuss the appropriate choice of the only metaparameter, the approximation rank. We finally showcase our method’s performance regarding runtime and accuracy in various experiments with real-world datasets.
A phase II clinical study on the efficacy and predictive biomarker of pegylated recombinant arginase on hepatocellular carcinoma
Authors: Chan Stephen L. , Cheng Paul N.M. , Liu Angela M. , Chan Landon L. , Li Leung , Chu Cheuk M. , Chong Charing C.N. , Lau Yat M. , Yeo Winnie , Ng Kelvin K.C. , Yu Simon C.H. , Mok Tony S.K. , Chan Anthony W.H.
Published: April 2021

Background: Pegylated recombinant human arginase (PEG-BCT-100) is an arginine depleting drug. Preclinical studies showed that HCC is reliant on exogenous arginine for growth due to the under-expression of the arginine regenerating enzymes argininosuccinate synthetase (ASS) and ornithine transcarbamylase (OTC). Methods: This is a single arm open-label Phase II trial to assess the potential clinical efficacy of PEG-BCT-100 in chemo naïve sorafenib-failure HCC patients. Pre-treatment tumour biopsy was mandated for ASS and OTC expression by immunohistochemistry (IHC). Weekly intravenous PEG-BCT-100 at 2.7 mg/kg was given. Primary endpoint was time to progression (TTP); secondary endpoints included radiological response as per RECIST1.1, progression free survival (PFS) and overall survival (OS). Treatment outcomes were correlated with tumour immunohistochemical expressions of ASS and OTC. Results: In total 27 patients were recruited. The median TTP and PFS were both 6 weeks (95% CI, 5.9–6.0 weeks). The disease control rate (DCR) was 21.7% (5 stable disease). The drug was well tolerated. Post hoc analysis showed that duration of arginine depletion correlated with OS. For patients with available IHC results, 10 patients with ASS-negative tumour had OS of 35 weeks (95% CI: 8.3–78.0 weeks) vs. 15.14 weeks (95% CI: 13.4–15.1 weeks) in 3 with ASS-positive tumour; expression of OTC did not correlate with treatment outcomes. Conclusions: PEG-BCT-100 in chemo naïve post-sorafenib HCC is well tolerated with moderate DCR. ASS-negative confers OS advantage over ASS-positive HCC. ASS-negativity is a potential biomarker for OS in HCC and possibly for other ASS-negative arginine auxotrophic cancers. Trial registration number: NCT01092091. Date of registration: March 23, 2010.
On an Implicit Model Linear in Both Stress and Strain to Describe the Response of Porous Solids
Authors: Itou Hiromichi , Kovtunenko Victor A. , Rajagopal Kumbakonam R.
Published: April 2021

We study some mathematical properties of a novel implicit constitutive relation wherein the stress and the linearized strain appear linearly that has been recently put into place to describe elastic response of porous metals as well as materials such as rocks and concrete. In the corresponding mixed variational formulation the displacement, the deviatoric and spherical stress are three independent fields. To treat well-posedness of the quasi-linear elliptic problem, we rely on the one-parameter dependence, regularization of the linear-fractional singularity by thresholding, and applying the Browder–Minty existence theorem for the regularized problem. An analytical solution to the nonlinear problem under constant compression/extension is presented.
New antidiabetic therapy and HFpEF: light at the end of tunnel?
Authors: Tadic Marijana , Sala Carla , Saeed Sahrai , Grassi Guido , Mancia Giuseppe , Rottbauer Wolfang , Cuspidi Cesare
Published: April 2021

New antidiabetic therapy that includes sodium-glucose co-transporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor (GLP-1R) agonists, and dipeptidyl peptidase 4 (DPP-4) inhibitors showed significant benefit on cardiovascular outcomes in patients with and without type 2 diabetes mellitus, and this was particularly confirmed for SGLT2 inhibitors in subjects with heart failure (HF) with reduced ejection fraction (HFrEF). Their role on patients with HF with preserved ejection fraction (HFpEF) is still not elucidated, but encouraging results coming from the clinical studies indicate their beneficial role. The role of GLP-1R agonists and particularly DPP-4 inhibitors is less clear and debatable. Findings from the meta-analyses are sending positive message about the use of GLP-1R agonists in HFrEF therapy and revealed the improvement of left ventricular (LV) diastolic function in HFpEF. Nevertheless, the relevant medical societies still consider their effect as neutral or insufficiently investigated in HF patients. The impact of DPP-4 inhibitors in HF is the most controversial due to conflicting data that range from negative impact and increased risk of hospitalization due to HF, throughout neutral effect, to beneficial influence on LV diastolic dysfunction. However, this is a very heterogeneous group of medications and some professional societies made clear discrepancy between saxagliptin that might increase risk of HF hospitalization and those DPP-4 inhibitors that have no effect on hospitalization. The aim of this review is to summarize current clinical evidence about the effect of new antidiabetic medications on LV diastolic function and their potential benefits in HFpEF patients.
Mediating Trauma and Anxiety: Letters to Françoise Dolto, 1976-1978
Authors: Bates Richard
Published: April 2021

Françoise Dolto (1908-88) was a prominent French cultural figure thanks to her practice of dispensing psychoanalytically-informed child-rearing advice via the radio. From 1976 to 1978, on her show Lorsque l’enfant paraît, she responded to thousands of letters sent in by listeners requesting help with parenting problems and personal questions of a psychological nature. The article explores Dolto’s cultural position as a child psychoanalyst – understood in the 1960s and 1970s as a radical profession – but from a conservative, Catholic background. It then examines a sample of the letters sent in to her show, analysing the demographics of the correspondents and highlighting their most common concerns. Finally the article studies the relationship between psychoanalysis and trauma. It indicates the anxiety that a psychoanalytic understanding can cause, by reinforcing parents’ fears that childhood traumas are common, can be created unwittingly by parents, and lead to major psychological consequences in later life.
Experimental determination of the temperature dependence of oxygen-isotope fractionation between water and chitinous head capsules of chironomid larvae
Authors: Lombino Alex , Atkinson Tim , Brooks Stephen J. , Gröcke Darren R. , Holmes Jonathan , Jones Vivienne J. , Marshall Jim D.
Published: April 2021

Oxygen-isotope values of invertebrate cuticle preserved in lake sediments have been used in palaeoenvironmental reconstructions, generally with the assumption that fractionation of oxygen isotopes between cuticle and water ($$\upalpha_{\text{cuticle}-\text{H}_{2}\text{O}}$$

α

cuticle
-

H
2

O

) is independent of temperature. We cultured chironomid larvae in the laboratory with labelled oxygen-isotope water and across a range of closely controlled temperatures from 5 to 25 °C in order to test the hypothesis that fractionation of oxygen isotopes between chironomid head capsules and water ($$\upalpha_{\text{chironomid}-\text{H}_{2}\text{O}}$$

α

chironomid
-

H
2

O

) is independent of temperature. Results indicate that the hypothesis can be rejected, and that $$\upalpha_{\text{chironomid}-\text{H}_{2}\text{O}}$$

α

chironomid
-

H
2

O

decreases with increasing temperature. The scatter in the data suggests that further experiments are needed to verify the relationship. However, these results indicate that temperature-dependence of $$\upalpha_{\text{chironomid}-\text{H}_{2}\text{O}}$$

α

chironomid
-

H
2

O

should be considered when chironomid δ18O is used as a paleoenvironmental proxy, especially in cases where data from chironomids are combined with oxygen-isotope values from other materials for which fractionation is temperature dependent, such as calcite, in order to derive reconstructions of past water temperature.
An Evaluation of Dual Systems Theories of Adolescent Delinquency in a Normative Longitudinal Cohort Study of Youth
Authors: Murray Aja Louise , Zhu Xinxin , Mirman Jessica Hafetz , Ribeaud Denis , Eisner Manuel
Published: April 2021

Dual systems theories of adolescent risk-taking propose that the socioemotional and self-regulation systems develop at different rates, resulting in a peak in sensation-seeking in adolescence at a time when self-regulation abilities are not yet fully mature. This “developmental imbalance” between bottom-up drives for reward and top-down control is proposed to create a period of vulnerability for high-risk behaviors such as delinquency, substance use, unprotected sex, and reckless driving. In this study, data from the Swiss longitudinal normative z-proso study (n = 1522,n = 784 male; aged 11, 13, 15, 17, and 20) were used to test whether the presence of a developmental imbalance between sensation-seeking and self-regulation is associated with trajectories of engagement in delinquency across early adolescence to adulthood. Using a latent class growth analysis of sensation-seeking, self-regulation, and delinquency, it was found that a model with 3 classes was optimal in the whole sample and male sub-sample, including one class characterized by a developmental imbalance and corresponding adolescent peak in delinquency. In females, there was no evidence for a class that could be described according to the trajectories hypothesized in dual systems theory. This study’s results support the claim that a developmental imbalance may drive an adolescent increase in delinquency. However, this applies only to a small subgroup of individuals, particularly males.
New and explicit constructions of unbalanced Ramanujan bipartite graphs
Authors: Burnwal Shantanu Prasad , Sinha Kaneenika , Vidyasagar Mathukumalli
Published: April 2021

The objectives of this article are threefold. Firstly, we present for the first time explicit constructions of an infinite family of unbalanced Ramanujan bigraphs. Secondly, we revisit some of the known methods for constructing Ramanujan graphs and discuss the computational work required in actually implementing the various construction methods. The third goal of this article is to address the following question: can we construct a bipartite Ramanujan graph with specified degrees, but with the restriction that the edge set of this graph must be distinct from a given set of “prohibited” edges? We provide an affirmative answer in many cases, as long as the set of prohibited edges is not too large.
Evolutionary responses of a dominant plant along a successional gradient in a salt-marsh system
Authors: Chen Qingqing
Published: April 2021

The ecological responses of plant populations along a successional gradient have been intensively examined; however, the evolutionary responses received much less attention. Here, I explored genetic changes of key phenotypic traits of a dominant clonal plant (Elytrigia atherica) along a saltmarsh successional gradient by collecting samples along the successional gradient in the high and low marsh and growing them in a common environment (greenhouse). Additionally, to explore whether changes in traits are driven by abiotic (e.g. clay thickness) and biotic (e.g. grazing intensity) variables along the successional gradient, I measured these two variables in the field. I found that clay thickness (a proxy of total nitrogen) increased along the successional gradient both in the high and low marsh; grazing intensity from hares (the most important herbivores) decreased along the successional gradient in the high marsh but did not change in the low marsh. Meanwhile, I found that growth in number of leaves and ramets decreased, while rhizome length increased, along the successional gradient for E. atherica collected from the high marsh. Opposite trends were found for E. atherica collected from the low marsh. Results suggest that, in the high marsh, herbivores may overrule nutrients to drive trait changes. That is, at the early successional stages, E. atherica had higher growth in number of leaves and ramets to compensate for high-intensity grazing. In the low marsh, nutrients may be the dominant driver for trait changes. That is, at the late successional stages, E. atherica had higher growth in number of leaves and ramets but shorter rhizomes to maximize its expansion under the favorable conditions (higher nutrient availability). Results suggest that ecologically important abiotic and biotic variables such as nutrients and herbivores may also have a substantial evolutionary impact on plant populations.
The follow-up of the robotic-assisted Soave procedure for Hirschsprung’s disease in children
Authors: Quynh Tran Anh , Hien Pham Duy , Du Le Quang , Long Le Hoang , Tran Nguyen Thi Ngoc , Hung Tran
Published: April 2021

Robotic surgery offers three-dimensional visualization and precision of movement that could be of great value to gastrointestinal surgeons. There were many previous reports on robotic technology in performing Soave colonic resection and pull-through for Hirschsprung’s disease in children. This study described the follow-up of the Robotic-assisted Soave procedure for Hirschsprung’s disease in children. Robotic-assisted endorectal pull-through was performed using three robotic arms and an additional 5-mm trocar. The ganglionic and aganglionic segments were initially identified by seromuscular biopsies. The rest of the procedure was carried out according to the Soave procedure. We left a short rectal seromuscular sleeve of 1.5–2 cm above the dentate line. From December 2014 to December 2017, 55 pediatric patients were operated on. Age ranged from 6 months to 10 years old (median = 24.5 months). The aganglionic segment was located in the rectum (n = 38), the sigmoid colon (n = 13), and the left colon (n = 4). The mean total operative time was 93.2 ± 35 min (ranging from 80 to 180 min). Minimal blood was lost during the surgery. During the follow-up period, 41 patients (74.6%) had 1–2 defecations per day, 12 patients (21.8%) had 3–4 defecations per day, and 2 patients (3.6%) had more than 4 defecations per day. Fecal incontinence, enterocolitis, and mild soiling occurred in three (5.4%), four (7.3%), and two pediatric patients, respectively. Robotic-assisted Soave procedure for Hirschsprung’s disease in children is a safe and effective technique. However, a skilled robotic surgical team and procedural modifications are needed.
Successful hemostasis of bleeding gastric inflammatory fibroid polyp by endoscopic treatment in a patient with severe COVID-19
Authors: Murota Ayako , Yoshi Shinji , Okuda Ryu , Oowada Sae , Yamakawa Tsukasa , Kazama Tomoe , Hirayama Daisuke , Ishigami Keisuke , Yamano Hiro-O. , Narimatu Eichi , Sugita Shintaro , Hasegawa Tadashi , Nakase Hiroshi
Published: April 2021

The coronavirus disease-2019 (COVID-19) has rapidly become a pandemic, resulting in a global suspension of non-emergency medical procedures such as screening endoscopic examinations. There have been several reports of COVID-19 patients presenting with gastrointestinal symptoms such as diarrhea and vomiting. In this report, we present a case of successful hemostasis of bleeding gastric inflammatory fibroid polyp by endoscopic treatment in a patient with severe COVID-19. The case was under mechanical ventilation with extracorporeal membrane oxygenation (ECMO), and the airway was on a closed circuit. This indicates that COVID-19 is associated with not only lung injury but also intestinal damage, and that proper protective protocols are essential in guaranteeing the best outcomes for patients and clinical professionals during this pandemic.
Extension of the process limits in laser beam welding of thick-walled components using the Laser Multi-Pass Narrow-Gap welding (Laser-MPNG) on the example of the nickel-based material Alloy 617 occ
Authors: Kessler Benjamin , Dittrich Dirk , Brenner Berndt , Standfuss Jens , Leyens Christoph
Published: April 2021

The joining of thick-walled components using beam-based joining techniques is content of worldwide research and development activities, but has not yet been established in industry. State of the art to weld nickel super alloys is currently a TIG narrow-gap welding. The present paper is focusing on a new specific laser beam welding process, the so-called Laser Multi-Pass Narrow-Gap welding (Laser-MPNG). It first explains the process principle based on 2D beam oscillation, the use of fiber lasers and the multi-pass principle. The potential of the Laser-MPNG welding process is demonstrated using the technically significant nickel-based material Alloy 617 occ. As a result, it was possible for the first time to realize a weld with a wall thickness of 140 mm free of cracks or bonding defects. Promising results of creep and low-cycle fatigue tests are used to show the potential that Laser-MPNG welded joints would have for future industrial applications.
Correction to: A New Definition of Voltage Unbalance Using Supply Phase Shift
Authors: Adekitan Aderibigbe Israel
Published: April 2021

A correction to this paper has been published: https://doi.org/10.1007/s40313-021-00722-z