bluuebunny/crossref_metadata_2025 huggingface dataset:
Kooperation und Konkurrenz – Eine Befragung ambulanter Hospizdienste zur Zusammenarbeit mit der SAPV
Authors: Heiß Kathrin , Jansky Maximiliane , Jaspers Birgit , Marx Gabriella , Schade Franziska , Nauck Friedemann , Banse Christian
Published: February 2022

Ziel Ziel der Befragung ist, die Auswirkungen der 2007 eingeführten Spezialisierten ambulanten Palliativversorgung (SAPV) auf die Arbeit ambulanter Hospizdienste (AHD) zu explorieren.

Methodik AHD wurden 2015 zu Änderungen der Wahrnehmung von und Erwartungen an die Hospizarbeit sowie zur Kooperation mit SAPV-Teams befragt. Die Auswertung erfolgte statistisch-deskriptiv sowie zusammenfassend qualitativ inhaltsanalytisch (Freitexte).

Ergebnisse 214 AHD für Erwachsene nahmen teil. Die Veränderung der Wahrnehmung von Hospizarbeit wurde mehrheitlich positiv bewertet. Fast alle AHD hatten überwiegend gute Erfahrungen in der Zusammenarbeit mit SAPV-Teams. SAPV verbessert die ambulante Palliativversorgung und verändert die Zusammenarbeit im Netzwerk, die Begleitungsanfragen, den Blick auf und die Erwartungen an AHD. Konkurrenz kann entstehen, wenn sich z. B. Aufgaben überschneiden oder sich der AHD verdrängt fühlt.

Schlussfolgerungen Die enge Kooperation von Haupt- und Ehrenamt in der Hospiz- und Palliativversorgung kann auch im Rahmen der SAPV zu einer besseren Versorgung schwerkranker und sterbender Patientinnen und ihrer Angehörigen führen. Die Rolle und die Aufgaben ehrenamtlicher Hospizarbeit müssen in den Bildungs- und Qualifizierungsangeboten zur Palliativversorgung adäquat vermittelt werden. Die gegenseitige Wahrnehmung, Kooperation sowie mögliche Konkurrenzen sollten auch aus Sicht der SAPV-Teams, der Patienten und Angehörigen untersucht werden.
Serious Adverse Drug Reactions in Children and Adolescents Treated
On- and Off-Label with Antidepressants and Antipsychotics in Clinical
Practice
Authors: Egberts Karin M. , Gerlach Manfred , Correll Christoph U. , Plener Paul L. , Malzahn Uwe , Heuschmann Peter , Unterecker Stefan , Scherf-Clavel Maike , Rock Hans , Antony Gisela , Briegel Wolfgang , Fleischhaker Christian , Häge Alexander , Hellenschmidt Tobias , Imgart Harmut , Kaess Michael , Karwautz Andreas , Kölch Michael , Reitzle Karl , Renner Tobias , Reuter-Dang Su-Yin , Rexroth Christian , Schulte-Körne Gerd , Theisen Frank M. , Walitza Susanne , Wewetzer Christoph , Fekete Stefanie , Taurines Regina , Romanos Marcel
Published: February 2022

Introduction Despite the growing evidence base for psychotropic drug
treatment in pediatric patients, knowledge about the benefit-risk ratio in
clinical practice remains limited. The ‘Therapeutic Drug Monitoring
(TDM)-VIGIL’ study aimed to evaluate serious adverse drug reactions
(ADRs) in children and adolescents treated with antidepressants and/or
antipsychotics in approved (‘on-label’), and off-label use in
clinical practice.

Methods Psychiatric pediatric patients aged 6-18 years treated with
antidepressants and/or antipsychotics either on-label or off-label were
prospectively followed between October 2014 and December 2018 within a
multicenter trial. Follow-up included standardized assessments of response,
serious ADRs and therapeutic drug monitoring.

Results 710 youth (age=14.6±2.2 years,
female=66.6%) were observed for 5.5 months on average;
76.3% received antidepressants, 47.5% antipsychotics, and
25.2% both. Altogether, 55.2% of the treatment episodes with
antidepressants and 80.7% with antipsychotics were off-label. Serious
ADRs occurred in 8.3% (95%CI=6.4–10.6%)
of patients, mainly being psychiatric adverse reactions (77.4%),
predominantly suicidal ideation and behavior. The risk of serious ADRs was not
significantly different between patients using psychotropics off-label and
on-label (antidepressants: 8.1% vs. 11.3%, p=0.16;
antipsychotics: 8.7% vs 7.5%, p=0.67). Serious ADRs
occurred in 16.6% of patients who were suicidal at enrollment versus
5.6% of patients who were not suicidal (relative risk 3.0,
95%CI=1.9-4.9).

Conclusion Off-label use of antidepressants and antipsychotics in youth
was not a risk factor for the occurrence of serious ADRs in a closely monitored
clinical setting. Results from large naturalistic trials like ours can
contribute to bridging the gap between knowledge from randomized controlled
trials and real-world clinical settings.
Förderpreis Nephrologische Pflege 2022
Authors: Schäfer Christian
Published: February 2022

Die Thieme Gruppe schreibt im Jahr 2022 wieder den Förderpreis Nephrologische Pflege aus und stiftet das Preisgeld von 1500 Euro.
Effects of Spectral Shaping on Speech Auditory Brainstem Responses to Stop Consonant-Vowel Syllables
Authors: Rishiq Dania , Harkrider Ashley , Springer Cary , Hedrick Mark
Published: February 2022

Abstract Background Spectral shaping is employed by hearing aids to make consonantal information, such as formant transitions, audible for listeners with hearing loss. How manipulations of the stimuli, such as spectral shaping, may alter encoding in the auditory
brainstem has not been thoroughly studied. Purpose The aim of this study was to determine how spectral shaping of synthetic consonant-vowel (CV) syllables, varying in their second formant (F2) onset frequency, may affect encoding of the syllables in the auditory brainstem.
Research Design We employed a repeated measure design. Study Sample Sixteen young adults (mean = 20.94 years, 6 males) and 11 older adults (mean = 58.60 years, 4 males) participated in this study. Data Collection and Analysis Speech-evoked
auditory brainstem responses (speech-ABRs) were obtained from each participant using three CV exemplars selected from synthetic stimuli generated for a /ba-da-ga/ continuum. Brainstem responses were also recorded to corresponding three CV exemplars that were spectrally shaped to decrease low-frequency
information and provide gain for middle and high frequencies according to a Desired Sensation Level function. In total, six grand average waveforms (3 phonemes [/ba/, /da/, /ga/] X 2 shaping conditions [unshaped, shaped]) were produced for each participant. Peak latencies and amplitudes, referenced
to prestimulus baseline, were identified for 15 speech-ABR peaks. Peaks were marked manually using the program cursor on each individual waveform. Repeated-measures analysis of variances were used to determine the effects of shaping on the latencies and amplitudes of the speech-ABR peaks.
Results Shaping effects produced changes within participants in ABR latencies and amplitudes involving onset and major peaks of the speech-ABR waveform for certain phonemes. Specifically, data from onset peaks showed that shaping decreased latency for /ga/ in older listeners, and
decreased amplitude onset for /ba/ in younger listeners. Shaping also increased the amplitudes of major peaks for /ga/ stimuli in both groups. Conclusions Encoding of speech in the ABR waveform may be more complex and multidimensional than a simple demarcation of source and
filter information, and may also be influenced by cue intensity and age. These results suggest a more complex subcortical encoding of vocal tract filter information in the ABR waveform, which may also be influenced by cue intensity and age.
A General Approach to Spirocyclic Piperidines via Castagnoli–Cushman Chemistry
Authors: Krasavin Mikhail , Peshkov Anatoly A. , Makhmet Azat , Bakulina Olga , Kanov Evgeny , Gainetdinov Raul , Peshkov Vsevolod A. , Dar’in Dmitry
Published: February 2022

Unsaturated spirocyclic lactams stemming from a variant of the three-component Castagnoli–Cushman reaction successfully underwent hydrogenation to enable access to fully saturated spirocyclic lactams. The subsequent lactam reduction gave rise to 2-spiro piperidine building blocks. The latter can be further elaborated in compound libraries and, on their own, show propensity to activate trace amine-associated­ receptor 1 (TAAR1), an important target for CNS disease.
A Case Report of Idiopathic OAT Syndrome, Associated with Necrospermia and Hypospermia, Reversed with Individualized Homeopathy
Authors: Ramanan Vinitha Edavattath , Sathyanandhan Silpa
Published: February 2022

Background Oligo-astheno-teratozoospermia (OAT) syndrome is one of the causes of male infertility, characterized by a decreased number of sperms (oligospermia), poor sperm motility (asthenospermia), and abnormal sperm shape (teratospermia). In necrospermia, spermatozoa in the ejaculated semen are dead, and in hypospermia, semen volume is less than 2 mL. The present case may be unique because of the association of all these features together in a single patient.

Method This idiopathic case was treated, from November 2016 to April 2017 in the National Homeopathy Research Institute in Mental Health, with the homeopathic medicine Natrium muriaticum. The Modified Naranjo Criteria for Homeopathy (MONARCH) score was used to assess the likelihood of causal attribution of the clinical outcome to the homeopathic medicine.

Result By the third month of starting homeopathic treatment, there was a marked improvement in sperm count from 14.4 to 77.4 million, semen volume from 0.8 to 2.2 mL, and normal forms from 14 to 75%. His wife became pregnant by the 5th month and delivered a healthy baby girl at full term. A MONARCH score of +9/13 indicates a positive causal relationship between the medicine prescribed and the treatment outcome.

Conclusion The present case report suggests a positive effect of individualized homeopathic medicine in treating a rare presentation of male infertility due to OAT syndrome.
Endotherapy in Pancreatic Diseases
Authors: Jearth Vaneet , Rana Surinder S.
Published: February 2022

Interventional endoscopy is now considered an effective minimally invasive treatment modality for the management of pancreatic diseases. It is important for the clinician to know the indications and contraindications as well as the timing of various endoscopic interventions. This will help in its safe and effective use and consequently decrease morbidity and mortality from various pancreatic diseases. This review will provide a broad overview of the indications, techniques, and outcomes of pancreatic endotherapy.
Botulinum Toxin Type A: Adverse Events and Management
Authors: Cavallini Maurizio , Papagni Marco , Lazzari Riccardo , Santorelli Adriano
Published: February 2022

Aesthetic medicine is witnessing an increasing exploitation of all the procedures. The demand has never been higher than it is today. The number of practitioners is also increasing year by year. Consequently complications and other kinds of related troubles and procedures are also rising. Never like today is fundamental, in case of troubles, how to properly manage with the most frequent issues. In aesthetic medicine field, botulinum toxin procedures are the safest. Lot of patients are worried about botulinum toxin despite the available scientific literature. Rare short-term complications are observed. In the most of cases, nothing severe occurs if the international recommendations and the most recent guidelines are closely followed, the majority of them are injection related. This study is a review of rare or common problems that can occur and how to manage or solve the situations.
Comparative Study of Fracture Outcome by Dynamic Compression Plating and Locking Compression Plating in Distal Tibial Fracture
Authors: Panigrahy Biswakesh , Behera Sanjib kumar , Hota Soubhagya Kumar , Nayak Ashok Kumar , Mohapatro Monalisa
Published: February 2022

Introduction Distal tibia fracture with or without fracture of fibula is very commonly encountered in young adults. The treatment protocol is mainly surgical with open reduction and internal fixation (ORIF) with plate and screw—contoured dynamic compression plating (DCP) or precontoured locking compression plating (LCP). In spite of advanced surgery, the outcome is not satisfactory with complications arising in 20 to 50% of patients. The purpose of this study was to determine the outcome and compare the two different modalities.

Materials and Methods The study includes 30 patients having distal tibial metaphyseal fracture without articular involvement treated with ORIF with plate and screw, contoured intraoperatively DCP and precontoured LCP in the Department of Orthopaedics. Patients were followed up for 12 to 24 months. Results were analyzed clinically (pain, alignment, range of motion, and complication) and radiologically. The patients were assessed according to time of full weight bearing, time of union of fracture, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Foot Functionality Index score.

Results The time of full weight bearing and time of union were found to be statistically significant in DCP and LCP. According to the grading of AOFAS score, in DCP, excellent: 3 cases (20%), good: 6 cases (40%), and fair: 6 cases (40%). In LCP, excellent 3 cases (20%), good 8 cases (53.33%), fair 4 cases (26.66%) were observed.

Conclusion LCP offers stability with early weight bearing and quicker fracture healing. But both groups had the same score at the final follow-up.
Advantages of the Delayed–Immediate Microsurgical Breast Reconstruction: Extending the Choice
Authors: Pittelkow Eric , DeBrock Will , Christopher Laura , Mercho Raphael , Suh Lily Ji-Yun , Fisher Carla S. , Hartman Brett , Lester Mary , Hassanein Aladdin H.
Published: February 2022

Background Deep inferior epigastric perforator (DIEP) reconstruction can be performed in an immediate (at time of mastectomy), delayed–immediate (immediate tissue expander followed by staged DIEP), or delayed timing following mastectomy. Avoiding flap radiation is a known benefit of the delayed–immediate approach. The purpose of this study is to evaluate patients who chose DIEP flap as the reconstructive method during initial consultation and compared characteristics of surgery in relation to their final reconstructive choice.

Methods Consecutive patients having breast reconstruction from 2017 to 2019 were divided into three groups: immediate DIEP after mastectomy (Group I); delayed–immediate DIEP with tissue expander first followed by DIEP (Group II); and patients who initially chose delayed–immediate DIEP but later decided on implants for the second stage of reconstruction (Group III). Exclusion criteria were patients that had delayed DIEP (no immediate reconstruction) or had initially chose implant-based reconstruction.

Results The study included 59 patients. Unilateral free flaps in Group II had shorter operative times (318 minutes) compared with Group I unilateral free flaps (488 minutes) (p = 0.024). Eleven patients (30.6%) had prophylactic mastectomies in Group I compared with none in Group II (p = 0.004). Patients who had immediate tissue expansion frequently changed their mind from DIEP to implant for second stage reconstruction frequently (52.2%).

Conclusion Delayed–immediate DIEP reconstruction has several advantages over immediate DIEP flap including shorter free flap operative times. Patients commonly alter their preference for second stage reconstruction. A patient-centered advantage of delayed–immediate reconstruction is prolonging the time for patients to make their choice for the final reconstruction.
Effects of Inflammation on Hemostasis in Acutely Ill Patients with Liver Disease
Authors: Driever Ellen G. , Lisman Ton
Published: February 2022

Patients with liver diseases are in a rebalanced state of hemostasis, due to simultaneous decline in pro- and anticoagulant factors. This balance seems to remain even in the sickest patients, but is less stable and might destabilize when patients develop disease complications. Patients with acute decompensation of cirrhosis, acute-on-chronic liver failure, or acute liver failure often develop complications associated with changes in the hemostatic system, such as systemic inflammation. Systemic inflammation causes hemostatic alterations by adhesion and aggregation of platelets, release of von Willebrand factor (VWF), enhanced expression of tissue factor, inhibition of natural anticoagulant pathways, and inhibition of fibrinolysis. Laboratory tests of hemostasis in acutely-ill liver patients may indicate a hypocoagulable state (decreased platelet count, prolongations in prothrombin time and activated partial thromboplastin time, decreased fibrinogen levels) due to decreased synthetic liver capacity or consumption, or a hypercoagulable state (increased VWF levels, hypofibrinolysis in global tests). Whether these changes are clinically relevant and should be corrected with antithrombotic drugs or blood products is incompletely understood. Inflammation and activation of coagulation may cause local ischemia, progression of liver disease, and multiorgan failure. Anti-inflammatory treatment in acutely-ill liver patients may be of potential interest to prevent thrombotic or bleeding complications and halt progression of liver disease.
Indocyanine Green Lymphography for Evaluation of Breast Lymphedema Secondary to Breast Cancer Treatments
Authors: Yamamoto Takumi , Yamamoto Nana
Published: February 2022

Background Although breast lymphedema (BL) significantly deteriorates quality of life (QOL) of breast cancer survivors, little is known and pathophysiological severity staging system is yet reported. This study aimed to evaluate usefulness of a novel BL severity staging system based on indocyanine green (ICG) lymphography findings.

Methods Breast cancer survivors with breast symptoms who underwent breast ICG lymphography were included. Breast ICG lymphography stage was determined based on visibility of linear pattern and extension of dermal backflow patterns. Prevalence of breast symptoms and lymphedema QOL score (LeQOLiS) was compared according to the stage.

Results Thirty-seven patients were included. Breast ICG lymphography stage included stage 0 in 11 (29.7%) cases, stage I in 3 (8.1%) cases, stage II in 11 (29.7%) cases, stage III in 6 (16.2%) cases, stage IV in 4 (10.8%) cases, and stage V in 2 (5.4%) cases. Higher ICG stages were associated with more frequent prevalence of breast swelling (p = 0.020), breast pain (p = 0.238), and breast cellulitis (p = 0.024), and with higher LeQOLiS (p < 0.001).

Conclusion ICG lymphography allows clear visualization of superficial lymph circulation in the breast. Higher breast ICG lymphography stages are associated with more frequent prevalence of BL-related symptoms and worse QOL.
Using new techniques to detect and sequence individual proteins
Authors: Thompson Avery
Published: February 2022

Developing technologies for single molecule protein sequencing to improve results in clinical and biological research
V-shaped traveling fronts of fractional Allen–Cahn equations
Authors: Ma Luyi , Niu Hong-Tao , Wang Zhi-Cheng
Published: February 2022

This paper is concerned with the existence and stability of V-shaped traveling fronts for the fractional Allen–Cahn equation in R2. By constructing a pair of super- and subsolutions, we establish the existence of V-shaped traveling fronts for each admissible speed. Furthermore, we show the uniqueness and stability of V-shaped traveling fronts.
A novel hybrid mode linear ultrasonic motor with double driving feet
Authors: Fu Daokuo , Fan Pingqing , Yuan Tao , Wang Yansong
Published: February 2022

A novel standing wave linear ultrasonic motor with double driving feet based on longitudinal-bending coupling mode is designed in this study. The motor adopts the bonded-type structure, and four pieces of piezoelectric ceramics on a metal beam are divided into two groups. Two voltages with 90° phase difference are applied to two groups of Pb-based lanthanumdoped zirconate titanates ceramics, respectively. Then the first longitudinal and second bending modes generated are superimposed on the stator, which can produce elliptical motion trajectories on the driving feet. The excitation method and driving mechanism of the motor are illustrated in detail. A finite model of the stator is established in the ANSYS parametric design language interface, and the operating mode of the stator and motion trajectories on the driving feet are discussed. The prototype is fabricated, and its impedance characteristics and mechanical output performance are tested. The results show that the maximal no-load velocity of the motor is ∼147.78 mm/s under a voltage of 200 V and a preload of 3 N. The maximum thrust force is ∼1.1 N when the voltage and preload are 200 V and 6 N, respectively.
Multi-output deep learning model for simultaneous prediction of figure of merits (I
on, G
m, and V
th) of gallium nitride high electron mobility transistors
Authors: Mishra Shivanshu , Chaturvedi Nidhi
Published: February 2022

This work reports on the development of a multi-output deep learning (DL) model for simultaneous prediction of the figure of merits (Ion, Gm, and Vth) of a gallium nitride (GaN) based high electron mobility transistors (HEMTs) for various epitaxial structures. To generate an initial data set, 2160 GaN HEMTs have also been simulated by an experimentally validated simulation methodology. A generative adversarial network (GAN) has been also introduced in semiconductor device modeling to augment the training data set. The generated data set by GAN is found to be in good agreement with the initial data set with a Frechet Inception Distance score of 0.151. The final data set has seven dimensions, i.e., aluminum gallium nitride (AlGaN) thickness (tAlGaN), aluminum content in AlGaN, doping in AlGaN, type of doping in AlGaN, Ion, Gm, and Vth, where the first four are inputs and the last three are the outputs of the DL model. The DL model is developed with the possibility of reducing unnecessary use of technology computer-aided design simulations for similar types of problems as such simulations require huge computational resources, expertise, and development time to obtain output. Mean squared error and R-squared values for the predicted Ion, Gm, and Vth are 59.69, 4.28, and 0.09, and 0.99, 0.99, and 0.97, respectively.
Scaling up silicon photonic-based accelerators: Challenges and opportunities
Authors: Al-Qadasi M. A. , Chrostowski L. , Shastri B. J. , Shekhar S.
Published: February 2022

Digital accelerators in the latest generation of complementary metal–oxide–semiconductor processes support, multiply, and accumulate (MAC) operations at energy efficiencies spanning 10–100 fJ/Op. However, the operating speed for such MAC operations is often limited to a few hundreds of MHz. Optical or optoelectronic MAC operations on today’s SOI-based silicon photonic integrated circuit platforms can be realized at a speed of tens of GHz, leading to much lower latency and higher throughput. In this Perspective, we study the energy efficiency of integrated silicon photonic MAC circuits based on Mach–Zehnder modulators and microring resonators. We describe the bounds on energy efficiency and scaling limits for N × N optical networks with today’s technology based on the optical and electrical link budget. We also describe research directions that can overcome the current limitations.
A study of space charge induced non-linearity in the Single Line Of Sight camera
Authors: Trosseille C. , Durand C. E. , Hurd E. R. , Dayton M. S. , Engelhorn K. , Hall G. N. , Holder J. P. , Landen O. L. , Carpenter A. C. , Nagel S. R.
Published: February 2022

A new generation of gated x-ray detectors at the National Ignition Facility has brought faster, enhanced imaging capabilities. Their performance is currently limited by the amount of signal they can be operated with before space charge effects in their electron tube start to compromise their temporal and spatial response. We present a technique to characterize this phenomenon and apply it to a prototype of such a system, the Single Line Of Sight camera. The results of this characterization are used to benchmark particle-in-cell simulations of the electrons drifting inside the detector, which are found to well reproduce the experimental data. These simulations are then employed to predict the optimum photon flux to the camera, with the goal to increase the quality of the images obtained on an experimental campaign while preventing the appearance of deleterious effects. They also offer some insights into some of the improvements that can be brought to the new pulse-dilation systems being built at Lawrence Livermore National Laboratory.
Effects of surplus heat and space charges on dynamic evolution of nanosecond repetitively pulsed discharges
Authors: Li Chenjie , Wang Yifeng , Zheng Xinlei , Zhao Zheng , Li Jiangtao
Published: February 2022

Effects of the surplus heat and space charges on the evolution of discharge dynamics and the discharge regime transition were investigated by a co-simulation platform consisting of a zero-dimensional (0D) plasma kinetics model and a two-dimensional (2D) Particle-In-Cell/Monte Carlo-Collision (PIC/MCC) model under repetitive nanosecond pulses. The results from the 0D plasma kinetics model show that the evolution could be defined as three stages: (a) initial cloud, (b) corona enhancement, and (c) quasi-stable spark. Surplus heat plays a key role in the transition from corona to spark. However, the evolution behavior under the corona enhancement stage cannot be explained by surplus heat alone. Detailed results from the 2D PIC/MCC model show that considering the effects of space charges, the transition from corona to spark tends to be hindered in the nanosecond repetitively pulsed discharges. A feedback mechanism for discharge evolution considering surplus heat and space charges is proposed in this paper, which provides a qualitative criterion for determining the evolutionary direction of corona discharge under repetitive nanosecond pulses.
Automatic electron hologram acquisition of catalyst nanoparticles using particle detection with image processing and machine learning
Authors: Ichihashi Fumiaki , Koyama Akira , Akashi Tetsuya , Miyauchi Shoko , Morooka Ken'ichi , Hojo Hajime , Einaga Hisahiro , Takahashi Yoshio , Tanigaki Toshiaki , Shinada Hiroyuki , Murakami Yasukazu
Published: February 2022

To enable better statistical analysis of catalyst nanoparticles by high-resolution electron holography, we improved the particle detection accuracy of our previously developed automated hologram acquisition system by using an image classifier trained with machine learning. The detection accuracy of 83% was achieved with the small training data of just 232 images showing nanoparticles by utilizing transfer learning based on VGG16 to train the image classifier. Although the construction of training data generally requires much effort, the time needed to select the training data candidates was significantly shortened by utilizing a pattern matching technique. Experimental results showed that the high-resolution hologram acquisition efficiency was improved by factors of about 100 and 6 compared to a scan method and a pattern-matching-only method, respectively.
Coupled cluster downfolding methods: The effect of double commutator terms on the accuracy of ground-state energies
Authors: Bauman Nicholas P. , Kowalski Karol
Published: February 2022

Downfolding coupled cluster techniques have recently been introduced into quantum chemistry as a tool for the dimensionality reduction of the many-body quantum problem. As opposed to earlier formulations in physics and chemistry based on the concept of effective Hamiltonians, the appearance of the downfolded Hamiltonians is a natural consequence of the single-reference exponential parameterization of the wave function. In this paper, we discuss the impact of higher-order terms originating in double commutators. In analogy to previous studies, we consider the case when only one- and two-body interactions are included in the downfolded Hamiltonians. We demonstrate the efficiency of the many-body expansions involving single and double commutators for the unitary extension of the downfolded Hamiltonians on the example of the beryllium atom, and bond-breaking processes in the Li2 and H2O molecules. For the H2O system, we also analyze energies obtained with downfolding procedures as functions of the active space size.
Deformable ferrofluid microrobot with omnidirectional self-adaptive mobility
Authors: Ji Yiming , Gan Chunyuan , Dai Yuguo , Bai Xue , Zhu Zixi , Song Li , Wang Luyao , Chen Huawei , Zhong Jing , Feng Lin
Published: February 2022

Magnetic soft robots have the potential to directly access areas of the human body that are currently inaccessible or difficult to reach for minimally invasive medical operations or drug delivery. Recently, ferrofluids containing magnetic nanoparticles with unique deformation properties have been extensively investigated. In this study, a ferrofluid robot for targeted drug delivery is proposed, while the control of ferrofluid robots is implemented in a 3D vascular model. Four-solenoid control systems with visual feedback are designed to achieve said implementation. Through numerical simulation and actual measurement, the magnetic field gradient generated by the system can reach 4.14 T/m, and three-dimensional control of ferrofluid robots can be realized. The deformation ability of ferrofluid robots is investigated, and the ferrofluid robots are found to pass through slits four times smaller than the diameter of the ferrofluid robots. Also, the deformation of the ferrofluid robots can reduce the drag force in the flow field by 43.75% through finite element simulation. The maximum control error does not exceed 0.3 mm. Finally, the coil system controls a ferrofluid droplet to achieve autonomous motion in a 3D vascular model with a maximum internal diameter of 3 mm. The implementation of the control effect allows for the technical potential of ferrofluid robots in drug delivery through vascular navigation.
Mid-infrared microring resonators and optical waveguides on an InP platform
Authors: Zhang Kevin , Böhm Gerhard , Belkin Mikhail A.
Published: February 2022

We demonstrate mid-infrared ring resonators fabricated in an In0.53Ga0.47As/InP materials platform operating at a wavelength of approximately 5.2 μm with quality factors over 120 000. We also perform broadband characterization of optical losses in passive In0.53Ga0.47As/InP ridge waveguides in the 5–11 μm wavelength range with waveguide losses ranging from below 0.5 dB/cm at shorter wavelengths to 4–5 dB/cm at longer wavelengths of this spectral range. Our results establish In0.53Ga0.47As/InP as a low-loss waveguiding platform for mid-infrared photonic integrated circuits that are fully integrable with InGaAs/AlInAs/InP quantum cascade lasers and detectors.
Laser-induced morphology-switchable slanted shape memory microcones for maneuvering liquid droplets and dry adhesion
Authors: Li Chuanzong , Jiao Yunlong , Li Dayu , Li Longfu , Peng Yubin , Jiang Shaojun , Zhang Yiyuan , Zhang Cong , Fan Shengying , Song Qingrui , Li Jianquan , Xiao Yi , Wu Sizhu , Chen Chao
Published: February 2022

Slanted micro-/nano-structures play pivotal roles in a diversity of fields, including water-proof engineering and fogdrop collection. In light of recent advances in fabricating slanted microstructures by using photolithography or reactive ion etching techniques, however, a complex, environmentally unfavorable, and tedious fabrication process makes them far from practical in application. Herein, we present a viable strategy to prepare a slanted shape memory microcone array (SSMMA) by combining the femtosecond laser oblique microfabrication and replica-mold method. Thanks to its fast temperature-responsive feature, SSMMA enables the transition of adhesion forces to effectively control the sliding of droplet on the surface. The underlying principle of the adjustable migration behavior of droplet is that SSMMA switches between the slanted and collapsed states. Moreover, we systematically studied the influence of the microcone spacing/height together with the microcone bending angle on the wetting performance of water droplet. More significantly, the resulted SSMMA analogous to a “machine hand” is experimentally demonstrated to be competent for the grab and transfer of fragile and smooth objects (e.g., coverslip) with a maximum adhesion force of ∼19.404 mN. The current study opens up an avenue for rapidly fabricating functional slanted microstructures for practical usage.
The performance of a soiled CSP system in Inner Mongolia under various weather conditions
Authors: Fu Jiating , Yan Suying , Zhao Xiaoyan , Zhao Ning , Gao Hongwei
Published: February 2022

Sand/dust storms (SDSs) are a common natural phenomenon occurring in the spring in arid and semi-arid areas. To investigate the influence of sand/dust on the performance of concentrating solar power systems, the effects of four SDS events and four natural dust deposition (NDD) periods were tested from March 7 to June 11, 2021, and were compared with the performance of the clean state. The results reveal that the sand/dust concentration on the mirror increased significantly after the occurrence of SDS events. In particular, after a severe sandstorm, the dust density was found to have reached 6.177 g/m2, which was 2.09 times that under the NDD exposure period of 40 days. With the increase in the dust density by 1 g/m2 after the occurrence of the four SDS events, the average reflectivity, energy flux density, and thermal efficiency were found to be decreased by 12.1%, 11.9%, and 12.5%, respectively, whereas they are decreased by 13.7%, 10.5%, and 13.7% under the four NDD periods.
Electrical detection of TV2a-type silicon vacancy spin defect in 4H-SiC MOSFETs
Authors: Abe Yuta , Chaen Akihumi , Sometani Mitsuru , Harada Shinsuke , Yamazaki Yuichi , Ohshima Takeshi , Umeda Takahide
Published: February 2022

Color centers in silicon carbide (4H-SiC) are potentially usable as spin defects for quantum sensing and quantum information technology. In particular, neutral divacancies (the P6/P7centers, VSiVC0) and a certain type of silicon vacancies (the TV2a center, VSi- at the k site) are promising for addressing and manipulating single spins. Although the TV2a spin is readable at room temperature, the readout techniques have been limited to luminescence-based ones (e.g., optically detected magnetic resonance). In this study, we demonstrated electrical detection of TV2a-type silicon vacancies at room temperature by using electrically detected magnetic resonance on 4H-SiC metal–oxide–semiconductor field effect transistors (MOSFETs). TV2a spin defects were embedded in the channel region of well-defined 4H-SiC MOSFETs via controlled proton irradiation. The number of detected TV2a spins was estimated to be ∼105. We also found that the charge state of the TV2a spin defect can be controlled by varying the gate voltage applied to the MOSFET.
A phase-field-based lattice Boltzmann model for multiphase flows involving N immiscible incompressible fluids
Authors: Yuan Xiaolei , Shi Baochang , Zhan Chengjie , Chai Zhenhua
Published: February 2022

In this work, an efficient and accurate lattice Boltzmann (LB) model is developed based on phase-field theory to study multiphase flows involving N (N≥2) immiscible incompressible fluids. In this model, a reduction-consistent physical formulation including a volume-fraction-dependent mobility in the Cahn–Hilliard (C–H) equations is adopted. Usually, the effect of cross-diffusion makes it difficult to solve such equations directly with the classic LB method. To avoid requiring a special treatment on the cross-diffusion terms of the chemical potential gradients, the proposed LB model introduces some non-diagonal collision operators. In addition, the proper auxiliary source terms are constructed to ensure the correct macroscopic equations. Through a direct Taylor expansion, the C–H equations are recovered from the present LB model. Finally, four classical problems including static droplets, the spreading of a liquid lens between two phases, the Kelvin–Helmholtz instability, and the dynamics of droplets in a four-phase system are used to demonstrate the capability of the LB model. The numerical results show that the present model satisfies the reduction-consistent property and produces physically accurate results.
The effect of strain and pressure on the electron-phonon coupling and superconductivity in MgB2—Benchmark of theoretical methodologies and outlook for nanostructure design
Authors: Johansson Erik , Tasnádi Ferenc , Ektarawong Annop , Rosen Johanna , Alling Björn
Published: February 2022

Different theoretical methodologies are employed to investigate the effect of hydrostatic pressure and anisotropic stress and strain on the superconducting transition temperature (Tc) of MgB2. This is done both by studying Kohn anomalies in the phonon dispersions alone and by explicit calculation of the electron–phonon coupling. It is found that increasing pressure suppresses Tc in all cases, whereas isotropic and anisotropic strain enhances the superconductivity. In contrast to trialed epitaxial growth that is limited in the amount of achievable lattice strain, we propose a different path by co-deposition with ternary diborides that thermodynamically avoid mixing with MgB2. This is suggested to promote columnar growth that can introduce strain in all directions.
Surface steps dominate the water formation on Pd(111) surfaces
Authors: Dietze Elisabeth M. , Chen Lin , Grönbeck Henrik
Published: February 2022

Water formation is relevant in many technological processes and is also an important model reaction. Although water formation over Pd surfaces is widely studied, questions regarding the active site and the main reaction path (OH* + OH*) or (OH* + H*) are still open. Combining first-principles density functional theory calculations and kinetic Monte Carlo simulations, we find that the reaction rate is dominated by surface steps and point defects over a wide range of conditions. The main reaction path is found to be temperature dependent where the OH* + OH* path dominates at low temperatures, whereas the OH* + H* path is the main path at high temperatures. Steps facilitate the OH* formation, which is the rate limiting step under all conditions. OH* is formed via O* + H* association or OOH* splitting at low temperatures, whereas OH* is exclusively formed via O* + H* association at high temperatures. The results of the first-principles-based kinetic model are in excellent agreement with experimental observations at high and low temperatures as well as different gas-phase compositions.
High performance millimeter-wave InAlN/GaN HEMT for low voltage RF applications via regrown Ohmic contact with contact ledge structure
Authors: Zhou Yuwei , Mi Minhan , Yang Mei , Han Yutong , Wang Pengfei , Chen Yilin , Liu Jielong , Gong Can , Lu Yiwei , Zhang Meng , Zhu Qing , Ma Xiaohua , Hao Yue
Published: February 2022

Benefitting from regrown Ohmic contact with a contact ledge structure, high performance millimeter-wave InAlN/GaN HEMT is fabricated to satisfy low voltage RF applications. Different from the commonly seen fabrication process for regrown Ohmic contact, the scheme proposed in this work features MBE regrowth of n+ GaN on the whole wafer after formation of regrowth well without masks and partial removal of n+ GaN grown on the access region by self-stopping etching. The remaining n+ GaN on the barrier, serving as contact ledges, provides an additional current path to achieve the reduced equivalent source-drain distance and, thus, improved output current, and more current contribution is made by contact ledge as the actual source-drain distance shrinks. With the assistance of contact ledge, the fabricated device demonstrates output current density of 2.8 A/mm, a peak extrinsic transconductance of 823 mS/mm, a knee voltage of 1.6 V, and an on-resistance of 0.47 Ω·mm. Although self-stopping etching is performed on the access region, the device exhibits ignorable current collapse. At 30 GHz and VDS of 6 V, decent power-added-efficiency of 52% together with output power density of 1.2 W/mm is achieved, revealing the great potential of the proposed regrown Ohmic contact with contact ledge structure for low voltage RF applications.
The fate of shear-oscillated amorphous solids
Authors: Liu Chen , Ferrero Ezequiel E. , Jagla Eduardo A. , Martens Kirsten , Rosso Alberto , Talon Laurent
Published: February 2022

The behavior of shear-oscillated amorphous materials is studied using a coarse-grained model. Samples are prepared at different degrees of annealing and then subjected to athermal and quasi-static oscillatory deformations at various fixed amplitudes. The steady-state reached after several oscillations is fully determined by the initial preparation and the oscillation amplitude, as seen from stroboscopic stress and energy measurements. Under small oscillations, poorly annealed materials display shear-annealing, while ultra-stabilized materials are insensitive to them. Yet, beyond a critical oscillation amplitude, both kinds of materials display a discontinuous transition to the same mixed state composed of a fluid shear-band embedded in a marginal solid. Quantitative relations between uniform shear and the steady-state reached with this protocol are established. The transient regime characterizing the growth and the motion of the shear band is also studied.
Tailoring orientation of microstructure for improving thermopower factor in Mg-doped CuCrO2 thick films
Authors: Van Hoang Dung , Pham Anh Tuan Thanh , Nguyen Truong Huu , Lai Hoa Thi , Truong Dai Cao , Le Thu Bao Nguyen , Ung Thuy Dieu Thi , Ohtani Masataka , Tran Vinh Cao , Phan Thang Bach
Published: February 2022

This study changed the material thickness (0.5–2.7 μm) to control the orientation of microstructure for tailoring the thermopower factor of CuCr0.85Mg0.15O2 films. As a result, the (110)-preferred orientation and copper vacancies were dominant in the thicker film, which increased conductivity σ. The Seebeck coefficient S remained unchanged within the wide film thickness range despite the remarkable increment in σ. Therefore, the thermopower factor (PF = S2σ) of the CuCr0.85Mg0.15O2 films drastically increased with the increase in the film's thickness, reaching 720 μW/mK2 at 500 °C in a 2.0 μm-thick CuCr0.85Mg0.15O2 film. This value is better than that observed in the bulk materials. A detailed discussion of physical mechanisms is presented in this manuscript.
Does (TaSe4)2I really harbor an axionic charge density wave?
Authors: Sinchenko A. A. , Ballou R. , Lorenzo J. E. , Grenet Th. , Monceau P.
Published: February 2022

A recent experimental work has reported an excess of the non-linear conductivity in the charge density wave (CDW) sliding mode of the quasi one-dimensional compound (TaSe4)2I, when a magnetic field is applied co-linearly to the electric field [Gooth et al., Nature 575, 315 (2019)]. This result has opened a conceptual approach, where the CDW gap in (TaSe4)2I is opened between Weyl fermions of opposite chirality with the assumption that this compound is a Weyl semi-metal in its undistorted high temperature phase. We report measurements in the sliding state of (TaSe4)2I performed in similar conditions. We have found no increase in the magnetoconductivity. In our attempts for understanding this unsettling discrepancy, we stress the specific nature of the Peierls transition in (TaSe4)2I and the strong electron-phonon coupling present in this compound. Given the lack of further evidence, we think that it is premature to assert that (TaSe4)2I is an axionic insulator.
Rescaling the near-wall predictive model for passive scalars in turbulent channel flow
Authors: Zhang Bo-Yuan , Huang Wei-Xi , Xu Chun-Xiao
Published: February 2022

The predictive model for near-wall velocity fluctuations [I. Marusic, R. Mathis, and N. Hutchins, “Predictive model for wall-bounded turbulent flow,” Science 329, 193–196 (2010)] is also valid for passive scalars transported in wall-bounded turbulent flows. However, the model parameters show strong Prandtl number (Pr) dependence under the viscous scaling. In the present study, we introduced the Prandtl-number-dependent length unit to scale the model parameters. Under the proposed scaling, the wall-normal positions of the outer peak of the scalar spectra coincide with 4.5ReτPr, where Reτ is the friction Reynolds number. With the large-scale signals extracted at this position as the model input, the Prandtl number dependence of the model parameters is greatly weakened, and the wall-normal position of zero modulation is independent of Prandtl numbers.
Unified gas-kinetic wave–particle method for gas–particle two-phase flow from dilute to dense solid particle limit
Authors: Yang Xiaojian , Shyy Wei , Xu Kun
Published: February 2022

A unified framework for particulate two-phase flow is presented with a wide range of solid particle concentration from dilute to dense limit. The two-phase flow is simulated by two coupled flow solvers, that is, the gas-kinetic scheme (GKS) for the gas phase and unified gas-kinetic wave–particle method (UGKWP) for the solid particle phase. The GKS is a second-order Navier–Stokes flow solver. The UGKWP is a multiscale method for all flow regimes. The wave and particle decomposition in UGKWP depends on the cell's Knudsen number (Kn). At a small Kn number, the highly concentrated solid particle phase will be modeled by the Eulerian hydrodynamic wave due to the intensive particle–particle collisions. At a large Kn number, the dilute solid particle will be followed by the Lagrangian particle to capture the non-equilibrium transport. In the transition regime, a smooth transition between the above limits is obtained according to the local Kn number. The distribution of solid particles in UGKWP is composed of analytical function and discrete particle, and both condensed and dilute phases can be automatically captured in the most efficient way. In the current scheme, the two-phase model improves the previous one in many aspects, such as drag force model, the frictional pressure formulation, and flux limiting model. The scheme is tested in many typical gas–particle two-phase problems, including the interaction of shock wave with solid particle layer, horizontal pneumatic conveying, bubble formation, and particle cluster phenomena in the fluidized bed. The results validate the GKS-UGKWP for the simulation of gas–particle flow.
Effect of void positioning on the detonation sensitivity of a heterogeneous energetic material
Authors: Coffelt Christopher , Olsen Daniel , Miller Christopher , Zhou Min
Published: February 2022

Although it is well-established that voids profoundly influence the initiation and reaction behaviors of heterogeneous energetic materials such as polymer-bonded explosives (PBX) and propellants, there has been little study of how void location in different constituents in the microstructures of such materials affect the macroscale behavior. Here, we use three-dimensional (3D) mesoscale simulations to study how void placement within the reactive grains vs the polymer binder influences the shock-to-detonation transition in a polymer-bonded explosive. The material studied here has a microstructure comprised of 75% PETN (pentaerythritol tetranitrate) grains and 25% hydroxyl-terminated polybutadiene polymer binder by volume. Porosities up to 10% in the form of spherical voids distributed in both the grains and polymer are considered. An Arrhenius reactive burn relation is used to model the chemical kinetics of the PETN grains under shock loading, thereby resolving the heterogeneous detonation behavior of the PBX. The influence of void location on the shock initiation sensitivity of the material is quantitatively ranked by comparing the predicted run distance to detonation (RDD) for each sample. The analysis includes inherent quantification of uncertainties arising from the stochastic variations in the microstructure morphologies and void distributions by using statistically equivalent microstructure sample sets, leading to probabilistic formulations for the RDD as a function of shock pressure. The calculations reveal that the location of voids in the composite microstructure significantly affects the RDD. Specifically, voids exclusively within the grains cause the PBX to be more sensitive (having shorter RDD) than voids in the polymer binder. Unique probabilistic relationships are derived to map the probability of observing RDD for each void location material case, allowing for prediction of initiation behavior anywhere in the shock pressure–RDD space. These findings agree with trends reported in the literature.