bluuebunny/crossref_metadata_2025 huggingface dataset:
Fast and Efficient Removal of Existing and Emerging Environmental Contaminants by 3D Graphene-based Adsorbents
Authors: Wang Haitao , Li Mingmei , Zhang Dongpeng , Liu Guoquan , Zhan Sihui
Published: March 2021

Integration of 2D graphene sheets into 3D graphene-based macrostructures (3D GBMs) could solve the separation challenges that preclude the wide application of graphene-based adsorbents. Apart from the inherent exceptional properties of the building blocks, the 3D GBMs also exhibit unique collective properties such as compressibility and interconnected porous structure. Owing to their novel collective properties, the application of 3D GBMs as adsorbents to remove various pollutants from water and air has attracted tremendous attention. The present chapter provides an overview of recent research studies and advances regarding the use of 3D GBMs as promising adsorbents for water treatment and air purification.
Freestanding Photocatalytic Materials Based on 3D Graphene for Degradation of Organic Pollutants
Authors: Ussia M. , Privitera V. , Carroccio S. C.
Published: March 2021

Heterogeneous photocatalysis holds enormous potential to transform a wide array of organic pollutants into relatively innocuous end products. Recently, 3D GBMs have emerged as a promising new class of metal-free photocatalysts, displaying semiconductor-like photoelectric properties and showing excellent photocatalytic performance owing to their unique interconnected structures, tunable porosity, ease of surface functionalization, outstanding electron-transfer efficiency and exceptional light-harvesting capabilities (from deep UV to the near-infrared). In this chapter, recent advances in the rational design of 3D GBM-based photocatalysts are highlighted and their applications in photocatalytic environmental remediation discussed. Additionally, the corresponding reaction mechanisms and pollutant transformation pathways are elucidated to fuel more disruptive and innovative research in this rapidly expanding field of industrial importance and practical relevance.
8 weeks of 2S-Hesperidin supplementation improves muscle mass and reduces fat in amateur competitive cyclists: randomized controlled trial
Authors: Martínez Noguera Francisco Javier , Alcaraz Pedro E. , Carlos Vivas Jorge , Chung Linda H. , Marín Cascales Elena , Marín Pagán Cristian
Published: March 2021

2S-Hesperidin is the main flavonoid of orange (Citrus sinensis). Previous researches have pointed its effects in muscle development and fat accumulation reduction, although most of these results have not been assessed in humans.
In situ self-organization of uniformly dispersed Co–N–C centers at moderate temperature without a sacrificial subsidiary metal
Authors: Bisen Omeshwari Yadorao , Nandan Ravi , Yadav Ashok Kumar , Pavithra Bellare , Kar Nanda Karuna
Published: March 2021

A one-pot, single step, eco-friendly methodology to promote uniform distribution of Co–Nx–C active centers with suppressed futile nanoparticle formation for electrochemical oxygen reduction.
Full quantum search for high Tc two-dimensional van der Waals ferromagnetic semiconductors
Authors: Liu Liang , Lin Zezhou , Hu Jifan , Zhang Xi
Published: March 2021

High throughput and accurate screening of 2D ferromagnetic semiconductors was conducted, predicting superior candidates and unveiling the crucial roles of quantum effects in 2D magnetism.
A general strategy for semiconductor quantum dot production
Authors: Xu Yuanqing , Wang Weibiao , Chen Zhexue , Sui Xinyu , Wang Aocheng , Liang Cheng , Chang Jinquan , Ma Yanhong , Song Luting , Jiang Wenyu , Zhou Jin , Liu Xinfeng , Zhang Yong
Published: March 2021

Bulk semiconductors are readily obtained by chemical precipitation. The as-obtained bulk semiconductors are then mechanically tailored into semiconductor quantum dots.
The electronic structure of FeV-cofactor in vanadium-dependent nitrogenase
Authors: Yang Zhi-Yong , Jimenez-Vicente Emilio , Kallas Hayden , Lukoyanov Dmitriy A. , Yang Hao , Martin del Campo Julia S. , Dean Dennis R. , Hoffman Brian M. , Seefeldt Lance C.
Published: March 2021

Active site FeV-cofactor of the V-nitrogenase and the EPR spectrum of the reduced cofactor showing 51V-hyperfine coupling.
A two fluorescent signal indicator-based ratio fluorometric alkaline phosphatase assay based on one signal precursor
Authors: Wang Rongji , Wang Zhihua , Rao Honghong , Xue Xin , Luo Mingyue , Xue Zhonghua , Lu Xiaoquan
Published: March 2021

A simple ratio fluorescent ALP biosensor based on MnO2 nanosheet-triggered in situ generation of two fluorescent signal indicators.
Tuning supported Ni catalysts by varying zeolite Beta heteroatom composition: effects on ethylene adsorption and dimerization catalysis
Authors: Meloni Michael , Runnebaum Ron C.
Published: March 2021

The influence of zeolite heteroatom composition on the electron density and catalytic activity of a supported Ni cation is examined.
Self-indicating and high-capacity mesoporous aerogel-based biosorbent fabricated from cellulose and chitosan via co-dissolution and regeneration for removing formaldehyde from indoor air
Authors: Liao Yang , Pan Xuejun
Published: March 2021

Cellulose–chitosan composite aerogel fabricated via a process of co-dissolution and regeneration can adsorb formaldehyde quickly and irreversibly from air.
Transient in situ measurement of kombucha biofilm growth and mechanical properties
Authors: Bertsch Pascal , Etter Danai , Fischer Peter
Published: March 2021

Interfacial shear rheology qualifies for transient in situ measurement of kombucha biofilm growth and mechanical properties, revealing that kombucha biofilm formation is a two-step process.
Correction: Protecting-group-free S-glycosylation towards thioglycosides and thioglycopeptides in water
Authors: Zhang Gao-Lan , Gadi Madhusudhan Reddy , Cui Xikai , Liu Ding , Zhang Jiabin , Saikam Varma , Gibbons Christopher , Wang Peng G. , Li Lei
Published: March 2021

Correction for ‘Protecting-group-free S-glycosylation towards thioglycosides and thioglycopeptides in water’ by Gao-Lan Zhang et al., Green Chem., 2021, DOI: 10.1039/d1gc00098e.
A fluorine induced enhancement of the surface polarization and crystallization of g-C3N4 for an efficient charge separation
Authors: Bai Xiaojuan , Wang Xuyu , Lu Xiongwei , Jia Tianqi , Sun Boxuan , Wang Cong , Hou Shanshan , Zong Ruilong
Published: March 2021

A synergy of high crystallinity and surface polarization constructed by F doping dramatically promotes charge separation efficiency, significantly enhancing photocatalytic activity.
High performance blue quantum light-emitting diodes by attaching diffraction wrinkle patterns
Authors: Qi Hui , Wang Shujie , Li Chenguang , Zhao Yaolong , Xu Bo , Jiang Xiaohong , Fang Yan , Wang Aqiang , Shen Huaibin , Du Zuliang
Published: March 2021

Quasi-periodic wrinkles are successfully used as a diffraction grating for extracting trapped light at the substrate/air interface, which can be adjusted from nano-scale to micron-scale, the optimized wrinkle device shows a peak EQE of 15.41%.
Functionalized aluminum-catalyzed silicon nanowire formation and radial junction photovoltaic devices
Authors: Jevasuwan Wipakorn , Fukata Naoki
Published: March 2021

Vertical Al-catalyzed SiNW arrays with shaped surfaces were synthesized by a one-step process and NW-based solar cells were demonstrated with optimized NW surface defects through surface modification and length reduction.
Proton conducting ABA triblock copolymers with sulfonated poly(phenylene sulfide sulfone) midblock obtained via copper-free thiol-click chemistry
Authors: Viviani Marco , Fluitman Sebastiaan Pieter , Loos Katja , Portale Giuseppe
Published: March 2021

The synthesis and characterization of novel proton conducting ABA triblock copolymers are reported. Structure-properties relationship of the block copolymers has been investigated at both the microscopic and macroscopic levels.
Radical-based functionalization-oriented construction: rapid assembly of azaarene-substituted highly functionalized pyrroles
Authors: Hu Weigao , Zhan Qiangqiang , Zhou Hongwei , Cao Shanshan , Jiang Zhiyong
Published: March 2021

A radical-based functionalization-oriented construction as a new synthetic strategy of azaarene variants is developed.
Hierarchically porous calcium–silicon nanosphere-enabled co-delivery of microRNA-210 and simvastatin for bone regeneration
Authors: Liu Junjie , Cui Yihang , Kuang Yudi , Xu Shan , Lu Qiji , Diao Jingjing , Zhao Naru
Published: March 2021

Co-encapsulation and co-delivery of miR-210 and simvastatin based on dual-sized pore structure calcium–silicon nanospheres for bone regeneration.
Rb3In(SO4)3: a defluorinated mixed main-group metal sulfate for ultraviolet transparent nonlinear optical materials with a large optical band gap
Authors: Xu Qinke , Jiang Xingxing , Wu Chao , Lin Lin , Huang Zhipeng , Lin Zheshuai , Humphrey Mark G. , Zhang Chi
Published: March 2021

An ultraviolet transparent nonlinear optical material Rb3In(SO4)3, which possesses a moderate SHG response and a large band gap, has been rationally designed through a defluorinated aliovalent substitution strategy.
Small molecule-doped organic crystals towards long-persistent luminescence in water and air
Authors: Muleta Desissa Yadeta , Song Jiawei , Feng Wenhui , Wu Ruitao , Zhou Xueqin , Li Wei , Wang Lichang , Liu Dongzhi , Wang Tianyang , Hu Wenping
Published: March 2021

A doped-crystalline material based on two organic small molecules exhibits visible long-persistent luminescence performance in aqueous solution or in air.
Massive MIMO systems for 5G: A systematic mapping study on antenna design challenges and channel estimation open issues
Authors: Benzaghta Mohamed , Rabie Khaled M.
Published: March 2021

The next generation of mobile networks (5G) is expected to achieve high data rates, reduce latency, as well as improve the spectral and energy efficiency of wireless communication systems. Several technologies are being explored to be used in 5G systems. One of the main promising technologies that is seen to be the enabler of 5G is massive multiple‐input multiple‐output (mMIMO) systems. Numerous studies have indicated the utility of mMIMO in upcoming wireless networks. However, there are several challenges that needs to be unravelled. In this paper, the latest progress of research on challenges in mMIMO systems is tracked, in the context of mutual coupling, antenna selection, pilot contamination and feedback overhead. The results of a systematic mapping study performed on 63 selected primary studies, published between the year 2017 till the second quarter of 2020, are presented. The main objective of this secondary study is to identify the challenges regarding antenna design and channel estimation, give an overview on the state‐of‐the‐art solutions proposed in the literature, and finally, discuss emerging open research issues that need to be considered before the implementation of mMIMO systems in 5G networks.
Prediction governors: Optimal solutions and application to electric power balancing control
Authors: Minami Yuki , Azuma Shun‐ichi
Published: March 2021

One of the control problems drawing engineers' and researchers' attention is the tracking control with predicted reference signals. The applications of this control problem are found in electric power control systems, automatic driving systems, and so on. The difficulty of the tracking control with the predicted signal is that the prediction errors lead to performance degradation of control systems. This paper aims to shape the predicted signals based on past information of reliable reference signal and system dynamics information to reduce the performance degradation caused by prediction errors. First, a signal shaping mechanism called prediction governor was proposed, and its optimal design problem was formulated. Then, an optimal solution for the design problem was analytically derived and the performance limitation of the prediction governor was clarified. The proposed optimal prediction governor is tailor‐made for a given control system. By adding it to the control system, the influence of the prediction error generated by a given prediction tool can be minimised. Finally, the usefulness of the proposed optimal prediction governor was illustrated through an electric power balancing control problem with a microgrid system.
Gastroenterologische Funktionsdiagnostik – neue Entwicklungen und Tipps für die Praxis
Authors: Barbone Gianluca , Jochum Christoph
Published: March 2021

Was ist neu?

Achalasie In den letzten 2 Jahren wurden mehrere Leitlinien unterschiedlicher Fachgesellschaften publiziert. Zur interventionellen Behandlung der Achalasie kommen die pneumatische Dilatation, die POEM sowie die Heller-Myotomie zur Anwendung. Bei der Durchführung der pneumatischen Dilatation ist ein sequenzielles Vorgehen empfohlen (1. Dilatation bis 30 mm, 4 Wochen später 2. Dilatation auf 35 mm).

SIBO Die bakterielle Fehlbesiedlung des Dünndarms ist ein klinisches Syndrom mit einem breiten Spektrum an Symptomen. Goldstandard ist die Kultur aus Duodenalsaft mit einem Cut-off von > 1000CFU/ml laut der neuen amerikanischen Leitlinie. Mit einer geringeren Sensitivität, aber hohen Spezifität ist der H2-Atemtest mit Glukose geeignet. Der Laktulose-Atemtest ist eher skeptisch zu bewerten.

IMO Als intestinal methanogen overgrowth (IMO) bezeichnet man eine Überwucherung von Methan-produzierenden Prokariota, welche mittels Durchführung eines Atemtests mit Messung des Methans in der Ausatemluft nachgewiesen werden kann. Diese Kondition ist teilweise mit einem Reizdarmsyndrom vom Obstipationstyp assoziiert.

COVID-19 und Funktionsdiagnostik Aufgrund der COVID-19-Pandemie hat in den letzten Monaten die Zahl an Untersuchungen in der gastroenterologischen Funktionsdiagnostik abgenommen – es wurden allerdings Empfehlungen zur Priorisierung veröffentlicht.
Inhalative Therapie der COPD – alle Patienten auf „fixed triple“?
Authors: Watz Henrik
Published: March 2021

Was ist neu?

Neue Studien mit „fixed triple“ Die 3 großen randomisierten, doppelblinden Phase-III-Studien TRIBUTE, IMPACT und ETHOS untersuchten den Stellenwert der 3-Fach-Fixkombination aus langwirksamen Beta-2-Sympathomimetika, langwirksamen Muskarinantagonisten und inhalativen Kortikosteroiden (LABA, LAMA, ICS) gegenüber den 2-Fachkombinationen (ICS/LABA oder LABA/LAMA). Die 3 Studien rekrutierten Patienten, bei denen Exazerbationen in den letzten 12 Monaten vor Studieneinschluss aufgetreten waren.
Fallbeispiele zur Rezessionsdeckung zur Klasse II nach Miller mittels bilaminärer Technik
Authors: Schoenebeck Claudia
Published: March 2021

Es werden 4 Fallbeispiele präsentiert zur Deckung von Rezessionen der Miller-Klasse II mittels bilaminärer Technik. Allen Fällen geht eine kieferorthopädische Behandlung voraus. Die Wurzeldeckung wurde mit einem Kombinationsverfahren aus Bindegewebstransplantat (BGT) und koronalem Verschiebelappen durchgeführt. Die Vorbehandlung und die genaue Operationsmethodik wird erläutert und postoperative Ergebnisse bis 3 Jahre post operationem dargestellt. Die erreichte Rezessionsdeckung der 4 Fallbeispiele entspricht den in der Literatur beschriebenen durchschnittlichen Rezessionsdeckungen von 84–98 % nach 2 Jahren bei einer Kombination aus Verschiebelappen mit BGT. Damit wurden mittels der bilaminären Technik gute ästhetische Operationsergebnisse erreicht. Bei allen beschriebenen Fällen kam es zur Entstehung von keratinisierter Gingiva. Ebenfalls wurde eine Verdickung des Gewebes erreicht, welche einen guten und stabilen Langzeiterfolg erwarten lässt.
Oberkiefer-Lückenschluss mittels Mesialslider und digitalem Workflow
Authors: Wilhelmy Lynn , Willmann Jan H. , Goldberg Maximilian , Wilmes Benedict , Drescher Dieter
Published: March 2021

Die Compliance-unabhängige Seitenzahn-Mesialisierung mittels Mini-Implantaten ist bei korrekter Indikationsstellung eine sehr gute Alternative zur Versorgung uni- oder bilateraler Lücken im Oberkiefer. Der Mesialslider zeigt eine ausgezeichnete körperliche Bewegung der Molaren. Verankerungsverluste, wie z. B. eine Abweichung der Frontmitte bei asymmetrischem Lückenschluss oder eine Kippung der Frontzähne nach palatinal, können vermieden werden. Das Finishing nach Lückenschluss mit Mesialslider kann mit einer Multibandapparatur in signifikant verkürzter Zeit oder auch durch Alignerschienen erfolgen. Der vorliegende Patientenfall zeigt, dass der kieferorthopädische Lückenschluss anhand eines digitalen Workflows vom intraoralen Scan bis hin zur Fertigstellung des Gerätes erfolgreich durchgeführt werden kann.
Invasive Pilzinfektionen bei Intensivpatienten – Was gibt es Neues?
Authors: Kochanek Matthias , Köhler Philipp
Published: March 2021

Was ist neu?

Invasive Candida-Infektionen Invasive Mykosen spielen in der Intensivmedizin eine zunehmende Rolle. Das Erkennen von Risikopatienten und das richtige Diagnose- und Therapiemanagement spielen dabei die entscheidende Rolle.

Influenza- und COVID-19-assoziierte pulmonale Aspergillose Neben der invasiven Candidiasis wurden zuletzt vermehrt Superinfektionen durch Schimmelpilze im Rahmen von schweren Influenza- und COVID-19-Infektionen beobachtet. Diese treten ohne die „klassischen“ Risikofaktoren für invasive Aspergillosen auf und bedürfen daher der besonderen Aufmerksamkeit der Intensivmediziner. Die Superinfektion mit Aspergillus-Spezies bei Influenza ist insofern neu, da bislang invasive Aspergillosen nur bei immunsupprimierten Patienten beschrieben wurden. Auch bei SARS-CoV-2 fanden sich schnell Berichte von COVID-19-assoziierten pulmonalen Aspergillosen, die möglicherweise zu einer Erhöhung der Mortalität führen können.
SARS-CoV-2-Impfungen – Was muss der Nephrologe wissen?
Authors: Heine Gunnar H. , Becker Sören L. , Scheuer Anja L. , Schirmer Stephan H.
Published: March 2021

Was ist neu?

Impfstoffe Innerhalb von nur 15 Monaten nach Beginn der COVID-19-Pandemie stehen bereits mehrere SARS-CoV-2-Impfstoffe zum klinischen Einsatz bereit. Während das Zielmolekül aller prädominierenden Vakzine das Spike-Protein von SARS-CoV-2 ist, lassen sie sich anhand ihres Wirkprinzip in mRNA-basierte, Vektor-basierte und Protein-basierte Impfstoffe unterscheiden.

Bedeutung für chronisch nierenkranke Menschen Das Aussprechen von Empfehlungen für chronisch nierenkranke Menschen ist aufgrund deren geringer Repräsentation in den Zulassungsstudien erschwert – wie bei anderen Patienten mit schwerer Komorbidität. Aufgrund von urämischem Immundefekt und/oder medikamentöser Immunsuppression könnte die Effektivität der Impfung im Einzelfall relativ vermindert sein. Dennoch profitieren vermutlich gerade diese Patienten von einer Impfung, da sie ein erhöhtes Risiko für einen schweren oder gar tödlichen COVID-19-Verlauf aufweisen.
Prävalenz und Schweregrad der apikalen Wurzelresorption während der kieferorthopädischen Behandlung mit klaren
Alignern und festsitzenden Apparaturen: eine Cone-Beam-Computertomografie-Studie
Authors: Jung Britta
Published: March 2021

Fragestellung

Ziel der retrospektiven Kohortenstudie war die Analyse der Prävalenz und Schwere von Wurzelresorptionen, die möglicherweise im Rahmen einer Alignertherapie im Vergleich zu einer konventionellen Therapie mit vestibulärem Multibandbracketapparaturen entstehen können.
Competency-Based Education in Minimally Invasive and Robotic Colorectal Surgery
Authors: Louridas Marisa , de Montbrun Sandra
Published: March 2021

Minimally invasive and robotic techniques have become increasingly implemented into surgical practice and are now an essential part of the foundational skills of training colorectal surgeons. Over the past 5 years there has been a shift in the surgical educational paradigm toward competency-based education (CBE). CBE recognizes that trainees learn at different rates but regardless, are required to meet a competent threshold of performance prior to independent practice. Thus, CBE attempts to replace the traditional “time” endpoint of training with “performance.” Although conceptually sensible, implementing CBE has proven challenging. This article will define competence, outline appropriate assessment tools to assess technical skill, and review the literature on the number of cases required to achieve competence in colorectal procedures while outlining the barriers to implementing CBE.
Training for Minimally Invasive Surgery for IBD: A Current Need
Authors: Kotze Paulo Gustavo , Holubar Stefan D. , Lipman Jeremy M. , Spinelli Antonino
Published: March 2021

Surgery for inflammatory bowel diseases (IBD) management has passed through an important evolution over the last decades, with innovative strategies and new technologies, especially in minimally invasive surgery (MIS) approaches. MIS procedures for IBD include multiport laparoscopy, single-port surgery, robotics, and the use of transanal platforms. These approaches can be used in the surgical management of both Crohn's disease (CD) and ulcerative colitis (UC). There are significant peculiarities in the surgical field in CD and UC, and their perfect understanding are directly related to better outcomes in IBD patients, as a consequence of improvement in knowledge by IBD surgeons. Different strategies to train colorectal surgeons were developed worldwide, for better application of MIS, usually for malignant or non-IBD benign diseases. There is a significant lack of evidence in specific training strategies for MIS in the IBD field. In this review, the authors outline the importance of adequate surgical training in IBD MIS, by discussing the current evidence on different approaches and emphasizing the need for better training protocols included in multidisciplinary teams in IBD centers throughout the globe.
Role of Simulation-Based Training in Minimally Invasive and Robotic Colorectal Surgery
Authors: Araujo Sergio Eduardo Alonso , Perez Rodrigo Oliva , Klajner Sidney
Published: March 2021

Properly performing minimally invasive colorectal procedures requires specific skills. With a focus on patient safety, the training of surgeons on patients is only accepted under exceptionally controlled, expensive, and challenging conditions. Moreover, many new techniques in colorectal surgery have been developed. Therefore, undertaking minimally invasive colorectal surgery in modern times requires specific psychomotor skills that trainee surgeons must gather in less time. In addition, there are not enough proctors with sufficient expertise for such an expressive number of new different techniques likes transanal and robotic procedures.

Studies that have demonstrated an improvement in minimally invasive surgery skills to the actual operating room in general surgery and a stepwise approach to surgical simulation with a combination of various training methods appears to be useful in colorectal surgery training programs. However, the scientific evidence on the transfer of skills specifically for colorectal surgery is extremely scarce and very variable. Thus, the evaluation of the results remains quite difficult. In this review, we present the best available evidence on the types of training based on simulation, their characteristics, advantages and disadvantages, and finally the results available on their adoption. Nevertheless, scientific evidence about the benefit of simulation training in minimally invasive colorectal surgery is limited and there is a need to build more robust evidence.
Training on Minimally Invasive Colorectal Surgery during Surgical Residency: Integrating Surgical Education and Advanced Techniques
Authors: Nebbia Martina , Kotze Paulo Gustavo , Spinelli Antonino
Published: March 2021

Surgery is an ever-evolving discipline and continually incorporates new technologies that have improved the ability of the operating room surgeon to perform. The next generation of minimally invasive surgery includes laparoscopic and robotic-assisted procedures. Graduating residents may be expected to have the skills to perform common colorectal procedures using these technologies, and residency programs are developing curriculums to teach these skills. Minimally invasive techniques are challenging and learning only by observation and practice alone is difficult. This requires dedicated training and mentoring.

New simulation methods have been conceived specifically for minimally invasive procedures, and these embrace a combination of virtual reality simulators and box trainers, with animal and human tissue, as well as synthetic materials. The aim of this review is to provide an overview of training in minimally invasive colorectal surgery with a focus on different types of simulators that build the basis to develop and include a multistep training approach in a structured training curriculum for minimally invasive colorectal procedures.
In-plane crystallographic orientations related spin-orbit torque in epitaxial Pt(111)/Co/Ta heterostructures
Authors: Bai Qiaoning , Mao Jian , Yun Jijun , Zhai Yongbo , Chang Meixia , Zhang Xu , Zhang Jianrong , Zuo Yalu , Xi Li
Published: March 2021

Current induced spin–orbit torque (SOT) in heavy metals with strong spin–orbit coupling strength has attracted considerable attention due to its potential applications in spintronic technology. Pt, as one of the mostly used heavy metals in SOT-based spintronic devices, shows large spin Hall angle (θSH) with its single phase and alloy counterparts. In this work, the in-plane crystallographic orientations related θSH of epitaxial Pt(111) layer is reported in MgO(111)/Pt(111)/Co/Ta heterostructures with strong perpendicular magnetic anisotropy. The θSH shows a quite large difference with values, respectively, around 0.083 and 0.057 when the current applied along the [11¯0] and [112¯] crystallographic directions of Pt(111) by the damping-like SOT efficiency using the harmonic Hall voltage measurement technique. The critical switching current densities also show large difference between these two orthogonal crystallographic orientations with the trend of that the larger SOT efficiency leads to the smaller critical switching current density. It independently confirms the generation of different damping-like SOT efficiency when current along [11¯0] and [112¯] directions of Pt(111). Moreover, a perpendicularly magnetized Pt/Co/Ta reference heterostructures with Pt having polycrystalline phase shows tiny variation of damping-like SOT efficiency in in-plane two orthogonal directions, which also indirectly indicates the crystallographic orientations related θSH in epitaxial Pt(111) layers. This study indicates that the θSH of epitaxial Pt is a crystallographic orientations related parameter.
Study of the crystal structure of SnS thin films by atomic layer deposition
Authors: Zhao Xizhu , Davis Luke M. , Lou Xiabing , Kim Sang Bok , Uličná Soňa , Jayaraman Ashwin , Yang Chuanxi , Schelhas Laura T. , Gordon Roy
Published: March 2021

Tin monosulfide, SnS, absorbs visible light and holds promise for thin-film photovoltaics. However, the optoelectronic properties of this material vary among the different structural phases, and control over the phase of vapor deposited SnS thin films is not well understood. In order to study the phases and crystallographic orientations of SnS films, films with thicknesses of 90 nm–750 nm were prepared by atomic layer deposition (ALD) at temperatures between 80 °C and 200 °C on amorphous silicon dioxide (a-SiO2) and single-crystal sodium chloride (NaCl). We show that the crystal structures and orientations of the ALD-SnS thin films vary with deposition temperature, film thickness, and substrate. We confirm the presence of metastable cubic π-SnS in co-existence with the thermodynamically stable orthorhombic α-SnS and find that the π phase is more prevalent at lower deposition temperatures. The films grown on a-SiO2 are textured, the degree of texturing increases with lower temperature or higher thickness, and the deposited phase is also thickness dependent. Upon annealing, which is known to promote SnS grain growth, all films revert to orthorhombic α-SnS. The films grown on the NaCl(100) substrate exhibit a much higher degree of texturing and show different preferred orientations dependent on the phase: π-(400) and α-(111) or α-(040). In addition, we demonstrate a proof-of-concept device made from the highly oriented SnS grown on NaCl.
Continuum gyrokinetic simulations of edge plasmas in single-null geometries
Authors: Dorf M. , Dorr M.
Published: March 2021

The first continuum gyrokinetic calculations of electrostatic ion scale turbulence are presented for the case of a diverted tokamak geometry. The simulation model solves the long-wavelength limit of the full-F gyrokinetic equation for ion species coupled to the quasi-neutrality equation for electrostatic potential variations, where a fluid model is used for an electron response. In order to facilitate simulations of highly-anisotropic microturbulence in the presence of strong magnetic shear and a magnetic X-point, a numerical algorithm utilizing a locally field-aligned multiblock coordinate system has been developed and implemented in the 5D finite-volume code COGENT. In this approach, the toroidal direction is divided into blocks, such that within each block, the cells are field-aligned and a non-matching grid interface is allowed at block boundaries. The toroidal angle corresponds to the “coarse” field-aligned coordinate, whereas the poloidal cross section, comprised of the radial and poloidal directions, is finely gridded to resolve short-scale perpendicular turbulence structures and to support accurate re-mapping (interpolation) at block boundaries. The 5D simulations explore cross-separatrix ion scale turbulence in the presence of a self-consistent radial electric field and address the effects of magnetic-shear stabilization in the X-point region.
Isothermal swirling flow characteristics and pressure drop analysis of a novel double swirl burner
Authors: Barakat S. , Wang Hui , Jin Tai , Tao Wenjie , Wang Gaofeng
Published: March 2021

Nonreacting swirling flow behavior through a novel double swirl burner has been investigated in this paper using Detached Eddy Simulation (DES) calculations and experimental measurements. The effect of mixing both the swirling flow of the inner jet (primary air or inner swirler) and the swirling flow of the annular jet (secondary air or outer swirler) on the flow structure has been analyzed. Moreover, pressure losses and flow field characteristics have been investigated at different inlet air mass flow rates and combustor diameters. Due to the drawbacks of general pressure loss to predict the pressure drop through high turbulence swirl flow as well as the complex geometry, the time-averaged viscous dissipation field function is used to predict the pressure drop through the burner. This function is based on the relationship between viscous dissipation and pressure losses. DES flow fields are compared with high-speed particle image velocimetry measurements at different inlet air mass flow rates. It is found that there is good agreement between numerical and experimental results, and both the central toroidal recirculation zone and the corner recirculation zone are well captured. In the case of a single inner swirler, the general pressure drop is very high compared to single outer and double swirl generators, and 84% of the inlet air pass through the outer swirler and just 16% of the air pass through the inner swirler in the case of a double burner (partially premixed). The time-averaged viscous dissipation field function is very important to identify the locations that lead to pressure drop inside the burner, which induces to select the appropriate design for the best performance. In addition, it is concluded that the performance of the double swirl burner is more efficient compared with the other two single swirlers in terms of pressure losses and flow structure.
Nonradiative subdiffraction near-field patterns using metagratings
Authors: Rabinovich Oshri , Epstein Ariel
Published: March 2021

We present a synthesis scheme to mold periodic nonradiative field patterns in transmission using the recent concept of metagratings (MGs). To this end, we utilize our previously developed analytical model to analyze the interaction of an incoming plane wave with these sparse periodic arrangements of polarizable particles (meta-atoms). As the model reliably predicts coupling to all scattered Floquet–Bloch modes, both propagating and evanescent, desired reactive near-field profiles with deep subwavelength features can be generated. This approach forms an appealing alternative to previously proposed near-field plates based on metasurfaces, where abstract homogenization introduces uncertainties regarding utilization of highly evanescent spectrum, and meta-atom realization incurs full-wave optimization. In contrast, the outlined MG-based methodology, verified via full-wave simulations, directly yields fabrication-ready printed-circuit-board configurations, enabling versatile control of reactive near fields with no interfering radiative components, with potential uses in sensing, selective microwave heating, and wireless power transfer.
Secondary instability of the hypersonic high-enthalpy boundary layers with thermal–chemical nonequilibrium effects
Authors: Chen Xianliang , Wang Liang , Fu Song
Published: March 2021

Compared to the widely studied linear instabilities, the nonlinear analyses of the high-enthalpy and hypersonic boundary-layer transition had received much less attention. In this work, secondary instabilities of high-enthalpy boundary layers are studied to highlight the impacts of thermal–chemical nonequilibrium (TCNE). The numerical tools adopted here are the nonlinear parabolized stability equation (NPSE) and the Floquet analysis (or the secondary instability theory, SIT). The flow over a blunt cone is computed at a free-stream Mach number of 20. The fundamental resonance is found to dominate over the subharmonic resonance. The development of secondary waves from SIT agrees well with that from NPSE, suggesting satisfactory cross-validation of both solvers. It is also illustrated that the disturbances of the species mass and vibrational temperature are mainly generated by the product term of the wall-normal velocity disturbance and the mean-flow gradient. The typical rope-like structures are observed near the boundary-layer edge. The effects of TCNE on the secondary instability are to cause larger maximum secondary growth rate and the corresponding azimuthal wavenumber.
Photoisomerization dynamics of spiropyran: A surface-hopping investigation
Authors: Granucci Giovanni , Padula Giancarlo
Published: March 2021

In the present work, we performed a computational investigation of the photoisomerization of spiro[1,3-dihydroindole-2,2′-chromene] [spiropyran (SP)] to merocyanine. The electronic energies and wavefunctions were obtained from configuration interaction calculations, using the floating occupation molecular orbital method, in a semiempirical framework. The parameters of the semiempirical Hamiltonian were re-optimized to reproduce ab initio literature data for SP. In our dynamics simulations, we considered, besides S0, the excited states S1, S2, and S3, which are very close in energy in the Franck–Condon region. We obtained a singlet lifetime of 0.67 ps, in line with the experimental results. We found the photoisomerization quantum yield to depend on the electronic state initially populated.
Bandgap engineering and sublattice distortion driven bandgap bowing in Cs2Ag1-xNaxBiCl6 double perovskites
Authors: C. Dakshinamurthy Athrey , Sudakar C.
Published: March 2021

Bandgap engineering in lead-free Cs2Ag1-xNaxBiCl6 (x = 0 to 1) double perovskite alloys synthesized through solution-based approach is investigated. The bandgap is shown to vary from 2.64 eV to 3.01 eV as Ag+ at B′ site gets replaced with Na+ cation. Despite a linear change in the lattice parameter according to Vegard's law, bandgap (Eg) changes in a nonlinear fashion for x = 0 to 1 with much lower Eg values observed than predicted by Vegard's rule. Further, we show the bandgap bowing effect in Cs2Ag1-xNaxBiCl6. Raman spectroscopic studies reveal that the changes in the vibrational mode positions arise due to the systematic variations in local distortions of [BiCl6]3– and [AgCl6]5– octahedra. The bandgap change, Raman mode frequency shift, Raman peak width, and the ratio of intensities of Raman modes all show a similar trend as a function of Na substitution concentration (x). The changes are minimal and linear for x from 0 to ∼0.6 and deviate sharply for higher Na concentration (x > 0.6). These observations strongly suggest that the sublattice distortion in the A2B′B″X6 lattice arises due to a mismatch in the octahedra. This imparts a nonlinear change in the bandgap. Thus, a strong interplay between the [Ag(Na)Cl6]5− and [BiCl6]3– octahedra is shown to have a significant influence on the deviation of bandgap from Vegard's rule and further enforces the bandgap bowing effect in Cs2Ag1-xNaxBiCl6.
Two-dimensional terahertz spectroscopy of condensed-phase molecular systems
Authors: Reimann Klaus , Woerner Michael , Elsaesser Thomas
Published: March 2021

Nonlinear terahertz (THz) spectroscopy relies on the interaction of matter with few-cycle THz pulses of electric field amplitudes up to megavolts/centimeter (MV/cm). In condensed-phase molecular systems, both resonant interactions with elementary excitations at low frequencies such as intra- and intermolecular vibrations and nonresonant field-driven processes are relevant. Two-dimensional THz (2D-THz) spectroscopy is a key method for following nonequilibrium processes and dynamics of excitations to decipher the underlying interactions and molecular couplings. This article addresses the state of the art in 2D-THz spectroscopy by discussing the main concepts and illustrating them with recent results. The latter include the response of vibrational excitations in molecular crystals up to the nonperturbative regime of light–matter interaction and field-driven ionization processes and electron transport in liquid water.
Detection of x rays by a surface acoustic delay line in contact with a diamond crystal
Authors: Topaltzikis Dimitrios , Wielunski Marek , Hörner Andreas L. , Küß Matthias , Reiner Alexander , Grünwald Theodor , Schreck Matthias , Wixforth Achim , Rühm Werner
Published: March 2021

In this study, we present proof of concept for an x-ray detector. The hybrid device consists of a synthetic single crystal diamond in mechanical contact with a piezoelectric lithium niobate surface acoustic wave (SAW) delay line. Upon x-ray irradiation, the diamond crystal experiences a change in conductivity, which, in turn, very sensitively influences the SAW transmission on the delay line. This change in SAW attenuation is directly used to monitor the x-ray beam intensity. The SAW attenuation shows a monotonic variation with dose rate D in the studied range between 100 and 1800 μGy/s. While the response time leaves room for further improvement, the SAW detection principle offers the unique possibility for wireless remote powering and sensing.
Effect of postgrowth processing technology and laser radiation parameters at wavelengths of 2091 and 1064 nm on the laser-induced damage threshold in ZnGeP2 single crystal
Authors: Yudin N.N. , Antipov O.L. , Gribenyukov A.I. , Eranov I.D. , Podzyvalov S.N. , Zinoviev M.M. , Voronin L.A. , Zhuravleva E.V. , Zykova M.P.
Published: March 2021

We report a study of the effect of postgrowth treatment of ZnGeP2 single crystals (low-temperature annealing, irradiation with fast electrons, polishing of working surfaces) and the conditions of exposure to repetitively pulsed laser radiation [wavelength (2091 or 1064 nm), pulse repetition rate, beam diameter, exposure time, sample temperature] on the laser-induced damage threshold (LIDT) of the surfaces of these crystals. It is found that thermal annealing of ZnGeP2 single crystals and their irradiation with a flux of fast electrons, which increase the LIDT at a wavelength of λ = 1064 nm, do not lead to a change in this threshold at λ = 2091 nm. It is shown that ZnGeP2 elements with lower optical losses in the spectral range 0.7 – 2.5 μm have a higher LIDT at λ = 2091 nm both immediately after fabrication and after postgrowth processing. An increase in the threshold energy density of laser radiation by a factor of 1.5 – 3 at λ = 2091 nm is revealed with a decrease in the crystal temperature from zero to –60 °C. The fact of reversible photodarkening of the propagation channel of laser radiation in ZnGeP2 in the predamage region of parameters is established by the method of digital holography.
Emerging pastoralist practices for fulfilling market requirements under stratified cattle production systems in Kenya’s drylands
Authors: Hallo Dabasso Bulle , Wasonga Oliver Vivian , Irungu Patrick , Kaufmann Brigitte
Published: March 2021

Context Stratified cattle production (SCP) systems, which involve buying lean animals from pastoral areas and fattening them in locations that have better production conditions, are re-emerging in Kenya’s drylands. Aims This study investigated how pastoralists in the drylands of Kenya endeavour to fulfil cattle marketing requirements under the SCP systems. Methods Purposefully identified cattle fattening entrepreneurs in Tana River (n = 10) and Narok (n = 12) counties were interviewed on the requirements they demand in buying animals from pastoralists. Using the information generated from the entrepreneurs, pastoralists (Tana River, n = 10; Narok, n = 12) were interviewed on how they respond to the entrepreneurs’ requirements and make sales. The information was triangulated with a focus group discussion in each county whose members were knowledgeable traders and pastoralists. Using a semi-structured questionnaire, randomly selected pastoral households (Tana River, n = 86; Narok, n = 69) were interviewed on cattle sales made through SCP systems. Key results The results showed that under the SCP systems, pastoralists in the two counties were required to sell cattle of particular qualities, comply with unpredictable supply orders, sell in secondary markets or near urban centres, use sale agents and undertake high commercial off-take rates if the demand arose. To meet these requirements, the pastoralists devised several strategies and practices, including changes in the animal husbandry practices, keeping ‘emergency’ animals in the home-based herds to comply with unpredictable demands, arrangements with market intermediaries to sell in secondary markets and building buyer–seller trust to facilitate sales through agents. In adopting these practices, pastoralists in both counties managed to sell approximately one or two animals per household through the SCP systems over a period of 12 months, which accounted for ~28% of the annual commercial cattle off-take from the households. Conclusion Pastoralists change their management practices in response to livestock marketing requirements and challenges, enhancing their integration into the market economy. Implication The information could guide stakeholders to formulate strategies for improving pastoralists’ involvement in cattle marketing through SCP systems.
Presynaptic α
2
δ subunits are key organizers of glutamatergic synapses
Authors: Schöpf Clemens L. , Ablinger Cornelia , Geisler Stefanie M. , Stanika Ruslan I. , Campiglio Marta , Kaufmann Walter A. , Nimmervoll Benedikt , Schlick Bettina , Brockhaus Johannes , Missler Markus , Shigemoto Ryuichi , Obermair Gerald J.
Published: March 2021

Significance

Voltage-gated calcium channels are important regulators of neuronal functions, as for example synaptic transmission. Their auxiliary α
2
δ subunits are modulating the calcium currents. Beyond that they have emerged as modulators of synaptic functions. Here, we established a cellular triple knockout/knockdown model in cultured hippocampal neurons by knocking out or knocking down the expression of all three α
2
δ subunits expressed in brain. Our experiments demonstrate that the presynaptic loss of α
2
δ proteins leads to a severe defect in glutamatergic synapse formation, which could be rescued by reintroducing any of the three neuronal α
2
δ isoforms. Thus, our study suggests that α
2
δ proteins are critical regulators of excitatory synapse formation and thereby contributes to the understanding of basic nerve cell functions.
A limited role of NKCC1 in telencephalic glutamatergic neurons for developing hippocampal network dynamics and behavior
Authors: Graf Jürgen , Zhang Chuanqiang , Marguet Stephan Lawrence , Herrmann Tanja , Flossmann Tom , Hinsch Robin , Rahmati Vahid , Guenther Madlen , Frahm Christiane , Urbach Anja , Neves Ricardo Melo , Witte Otto W. , Kiebel Stefan J. , Isbrandt Dirk , Hübner Christian A. , Holthoff Knut , Kirmse Knut
Published: March 2021

Significance

Neuronal circuits develop in an activity-dependent manner. In vitro data suggest that the intracellular accumulation of chloride—a universal characteristic of immature nerve cells—drives network maturation through a depolarizing action of the neurotransmitter GABA. We here demonstrate that deletion of the chloride cotransporter NKCC1 from forebrain pyramidal cells severely impairs hippocampal network synchrony in vitro. In contrast, NKCC1 has weak and event type-dependent effects on spontaneous network activity in vivo, and loss of NKCC1 leaves the maturation of synaptic properties, network dynamics, and hippocampus-dependent behaviors largely unaffected. Our data reveal a subtle neural network function of NKCC1 in hippocampal glutamatergic neurons in vivo, but challenge the assertion that NKCC1 in this major cell type is central to hippocampal development.
Mapping temperature-dependent conformational change in the voltage-sensing domain of an engineered heat-activated K
+
channel
Authors: Chen Hongbo , Deng Jiahua , Cui Qiang , Chanda Baron , Henzler-Wildman Katherine
Published: March 2021

Significance

Our understanding of fundamental biophysical mechanisms that underlie temperature-dependent gating remains limited despite the elucidation of structures of thermosensitive ion channels. According to current thinking, thermosensitive channels are expected to undergo a significant change in solvation upon activation by temperature, but direct evidence of such a change is lacking. Here, we utilize NMR spectroscopy and atomistic simulations to probe the solvation dynamics of an engineered temperature-sensitive variant of Shaker potassium channel at two different temperatures. Our studies reveal that this temperature-sensitive variant undergoes a dramatic shift in hydration at higher temperatures in contrast to the wild-type channels. Our findings illustrate how point mutations can cause dramatic differences in overall solvation dynamics and thereby alter temperature-dependent function.
A scalable empathic supervision intervention to mitigate recidivism from probation and parole
Authors: Okonofua Jason A. , Saadatian Kimia , Ocampo Joseph , Ruiz Michael , Oxholm Perfecta Delgado
Published: March 2021

Significance

Recidivism to incarceration is a pervasive and costly societal issue and its rates are historically difficult to reduce. Psychology and criminology suggest that relationships between probation and parole officers (PPOs) and adults on probation or parole (APPs) play a pivotal role in whether APPs ultimately return to incarceration and that mindsets geared toward empathy may protect the relationship from psychological barriers to productive interactions. The present research tests the efficacy an empathic-supervision exercise with PPOs to mitigate recidivism in a longitudinal, randomized placebo-controlled field experiment with 216 officers who supervise ∼20,478 APPs. As compared to a control condition, the treatment mitigated recidivism by 13% over the course of 10 mo.