bluuebunny/crossref_metadata_2025 huggingface dataset:
Phosphine-catalyzed hydroboration of propiolonitriles: access to (E)-1,2-vinylcyanotrifluoroborate derivatives
Authors: Bowen Johnathan , Slebodnick Carla , Santos Webster L.
Published: April 2022

We report an organocatalytic trans hydroboration of 3-substituted-propiolonitriles. The reaction proceeds through a 1,2-phosphine addition instead of a canonical 1,4-conjugate addition pathway.
Encapsulation of AgInS2/GaSx core/shell quantum dots in In-fumarate metal–organic frameworks for stability enhancement
Authors: Tepakidareekul Manunya , Uematsu Taro , Torimoto Tsukasa , Kuwabata Susumu
Published: April 2022

Cadmium-free AgInS2/GaSx core/shell QDs with a spectrally narrow band-edge emission were encapsulated using indium MOFs to improve stability.
First-principles study of polymer-passivated silicon nanowire outer-shell defects
Authors: Wei Lijing , Li Feng , Pang Shaoyuan , Wang Yinglong , Guo Jianxin , Chen Jianhui
Published: April 2022

The Nafion molecule could firmly adsorb on the surfaces of SiNWs. The HOMO and LUMO were confined to the center of the SiNW due to being wrapped by the Nafion, exhibiting an equivalent quantum confinement effect compared with the H-passivated SiNWs.
Volume viscosity and ultrasonic relaxation of ethanol–water mixtures studied by molecular dynamics simulations
Authors: Yamaguchi Tsuyoshi
Published: April 2022

Molecular dynamics simulation analysis shows that the large volume viscosity of ethanol–water mixtures is ascribed to long-range concentration fluctuation.
On surface chemical reactions of free-base and titanyl porphyrins with r-TiO2(110): a unified picture
Authors: Schio Luca , Forrer Daniel , Casarin Maurizio , Goldoni Andrea , Rogero Celia , Vittadini Andrea , Floreano Luca
Published: April 2022

Free-base porphyrins on TiO2(110) anchor to Obr rows, where they capture diluted hydrogen underneath and favour outdiffusion of Ti interstitials by self-metalation; Ti metalated species may also capture oxygen from hydroxyl adsorbates on Ti5f rows.
Relativistic nonorthogonal configuration interaction: application to L2,3-edge X-ray spectroscopy
Authors: Grofe Adam , Li Xiaosong
Published: April 2022

In this article, we develop a relativistic exact-two-component nonorthogonal configuration interaction (X2C-NOCI) for computing L-edge X-ray spectra.
Application of super-resolution and correlative double sampling in cryo-electron microscopy
Authors: Sheng Yuewen , Harrison Peter J. , Vogirala Vinod , Yang Zhengyi , Strain-Damerell Claire , Frosio Thomas , Himes Benjamin A. , Siebert C. Alistair , Zhang Peijun , Clare Daniel K.
Published: April 2022

A comparison of STA and SPA processed data acquired with/without super-resolution imaging mode enabled.
Shaping MOF oxime oxidation catalysts as three-dimensional porous aerogels through structure-directing growth inside chitosan microspheres
Authors: Hammi Nisrine , Chen Shuo , Primo Ana , Royer Sebastien , Garcia Hermenegildo , El Kadib Abdelkrim
Published: April 2022

MOF-based recyclable catalysts can be grown and shaped as porous aerogels using chitosan microspheres.
Super-2D metal organic frameworks with vertical layer skeletons and good adsorption performances
Authors: Yang Pan , Wang Youfu
Published: April 2022

Super-2D MOFs with vertical layered skeletons promoted the accessibility to external guests and exhibited good adsorption performances for various adsorbates.
Computational insight into the mechanism and stereoselectivity of cycloaddition between donor–acceptor spirocyclopropane and aldehyde catalyzed by Brønsted acid TsOH
Authors: Chen Yao , Zhang Yan , Xue Ying
Published: April 2022

The density functional theory computation was used to study the mechanism and selectivity of a Brønsted acid TsOH catalyzed cycloaddition reaction.
Predicting Lyman-continuum emission of galaxies using their physical and Lyman-alpha emission properties
Authors: Maji Moupiya , Verhamme Anne , Rosdahl Joakim , Garel Thibault , Blaizot Jérémy , Mauerhofer Valentin , Pittavino Marta , Victoria Feser Maria-Pia , Chuniaud Mathieu , Kimm Taysun , Katz Harley , Haehnelt Martin
Published: April 2022

Aims.The primary difficulty in understanding the sources and processes that powered cosmic reionization is that it is not possible to directly probe the ionizing Lyman-continuum (LyC) radiation at that epoch as those photons have been absorbed by the intervening neutral hydrogen. It is therefore imperative to build a model to accurately predict LyC emission using other properties of galaxies in the reionization era.

Methods.In recent years, studies have shown that the LyC emission from galaxies may be correlated to their Lyman-alpha (Lyα) emission. In this paper we study this correlation by analyzing thousands of simulated galaxies at high redshift in the SPHINX cosmological simulation. We post-process these galaxies with the Lyαradiative transfer code RASCAS and analyze the Lyα– LyC connection.

Results.We find that the Lyαand LyC luminosities are strongly correlated with each other, although with dispersion. There is a positive correlation between the escape fractions of Lyαand LyC radiations in the brightest Lyman-alpha emitters (LAEs; escaping LyαluminosityLescLyα> 1041erg s−1), similar to that reported by recent observational studies. However, when we also include fainter LAEs, the correlation disappears, which suggests that the observed relation may be driven by selection effects. We also find that the brighter LAEs are dominant contributors to reionization, withLescLyα> 1040erg s−1galaxies accounting for > 90% of the total amount of LyC radiation escaping into the intergalactic medium in the simulation. Finally, we build predictive models using multivariate linear regression, where we use the physical and Lyαproperties of simulated reionization era galaxies to predict their LyC emission. We build a set of models using different sets of galaxy properties as input parameters and predict their intrinsic and escaping LyC luminosity with a high degree of accuracy (the adjustedR2of these predictions in our fiducial model are 0.89 and 0.85, respectively, whereR2is a measure of how much of the response variance is explained by the model). We find that the most important galaxy properties for predicting the escaping LyC luminosity of a galaxy are itsLescLyα, gas mass, gas metallicity, and star formation rate.

Conclusions.These results and the predictive models can be useful for predicting the LyC emission from galaxies using their physical and Lyαproperties and can thus help us identify the sources of reionization.
Identification of influential patterns of chemical treatment of sugar production thick juice and remelt syrups on the beet sugar quality
Authors: Gorodecky Vladimir , Semenikhin Semen , Daisheva Nailya , Kotlyarevskaya Natalya , Fabritskaya Alla
Published: April 2022

Laboratory studies have been carried out on the effect of chemical treatment with the use of various sulfite-containing reagents of sugar production concentrated intermediates - thick juice and remelt syrups on the beet sugar quality. It has been established that the chemical treatment of concentrated intermediates with the use of sulfur dioxide provides a greater reduction in their color compared to sodium bisulfite – from 996,7 to 830,30 and 857,30 ICUMSA units, respectively. It has been established that chemical treatment with the use of sulfite-containing reagents improves the quality of the resulting sugar. It has been established that during longterm storage (up to 100 days) of concentrated sugar-containing intermediates, their color increases, however, preliminary chemical treatment with the use of sulfur dioxide provides the least increase in color during storage, compared with treatment with sodium bisulfite. The increase in color after 100 days of storage relative to the initial values was 18,46 and 36,26%, respectively.
Biotechnological methods used in the cultivation and storage of fruits
Authors: Prichko Tatiana
Published: April 2022

The article presents information on the biologization of technological processes in the cultivation and storage of fruits based on the use of biological preparations, microorganisms, and technological storage factors. The effectiveness of the natural biological growth regulator Gibbersib, obtained from microorganisms, is noted, which makes it possible to increase the yield, accelerate the ripening time and improve the chemical composition of apples. Due to the vital activity of microorganisms, the possibility of enhancing the color of fruits associated with an increase in the content of anthocyanins in the skin of apples has been established. Based on the use of chemical methods of influencing fruits during cultivation - Harvista ™ and storage - SmartFresh ™, regularities for controlling the rate of apple ripening in combination with optimization of technological parameters of storage in a controlled environment have been established at the cellular level
Research of the survival of a consortium of Zygosaccharomyces kombuchaensis yeast and Gluconoacetobacter xylinus bacteria during frozen storage using various protective media
Authors: Babakina Maria , Pershakova Tatyana , Samoylenko Maria , Semiryazhko Elizaveta
Published: April 2022

In the present study the survival of the consortium of yeast and bacteria using protective media was investigated. The protective medium consisting of 1 % gelatin, 5 % monosodium glutamate and 5 % sucrose provides the best preservation of living cells of the consortium and allows stabilization of cells for up to 100 days at storage temperatures from -2 °C to -10 °C. The projective medium consisting of 1 % gelatin and 10 % sucrose provides effective storage of the cells at t=-2 °C for 100 days; t=-5 °C – 80 days; t=-10 °C – 60 days. The projective medium of skimmed milk and 7.5 % glucose ensures effective storage of the cells of the consortium at t=-2 °C for 100 days; t=-5 °C – 80 days; t=-10 °C – 80 days. The information obtained is interesting for following researches of the development of technologies for the bioconversion of plant materials.
Hydrogenation of sputtered ZnO:Al layers for double side poly-Si/SiOx solar cells
Authors: Seron Charles , Desrues Thibaut , Jay Frédéric , Lanterne Adeline , Torregrosa Frank , Borvon Gaël , Rafhay Quentin , Kaminski Anne , Dubois Sébastien
Published: April 2022

This work presents the development and the application of innovative and sustainable transparent conductive oxide (TCO) materials for contacting polysilicon (poly-Si) on oxide (SiOx) stacks used as passivating contacts in solar cell devices. Adding hydrogen into ZnO:Al (AZO) layers deposited by magnetron sputtering potentially leads to a twofold positive effect. First, it brings hydrogen atoms into the layers, which can enhance both electrical and optical material properties of the TCO. Second, hydrogen can significantly improve cell performances, by fixing dangling bonds at the SiOx/substrate interface and by passivating bulk defects. In situ and ex situ hydrogenation processes have been compared on those multiple aspects with investigation about anneals at 350 °C. AZO layers have been successfully integrated on the front side of complete solar cells featuring poly-Si/SiOx-based passivating contacts, leading to a record conversion efficiency of 22.4% for a cell with AZO. The results show that using AZO instead of an indium based TCO is suitable for passivated contacts solar cell with high temperature route. Thus, it increases the credibility towards large-scale deployments of TCO-based high efficiency silicon solar cells in terms of cost and resources.
„Gehört der Arm zu mir?“ – Erfahrungen von Patienten in Regionalanästhesie
Authors: Teppe Lena
Published: April 2022

Wie erleben Patienten Operationen im wachen Zustand und was wünschen sie sich während der intraoperativen Betreuung? Eine Studie liefert Antworten und gibt Handlungsempfehlungen für die intraoperative Pflege.
Hämodynamisches Monitoring 2.0 – was ist auf Normalstation möglich?
Authors: Schiewe Robert , Bein Berthold
Published: April 2022

Neben der Verwendung von Scores zur Früherkennung sich kritisch verschlechternder Patienten kann die Patientensicherheit durch zusätzliches Monitoring auch auf der Normalstation erhöht
werden. Hierbei ist die Praktikabilität von entscheidender Bedeutung, wodurch die Auswahl geeigneter nichtinvasiver Verfahren im Rahmen der Behandlung auf Normalstation eingeschränkt
ist.
Offen und empathisch kommunizieren
Authors: Wagenhäuser Kirsten
Published: April 2022

Im CNE Schwerpunkt erfahren Sie, wie Sie wache Patienten prä-, intra- und postoperativ professionell und einfühlsam versorgen und warum Kommunikation dabei eine entscheidende Rolle spielt.
Valproic Acid Initiates Transdifferentiation of the Human Ductal
Adenocarcinoma Cell-line Panc-1 Into α-Like Cells
Authors: Petry Sebastian Friedrich , Kandula Naga Deepa , Günther Stefan , Helker Christian , Schagdarsurengin Undraga , Linn Thomas
Published: April 2022

Non-mesenchymal pancreatic cells are a potential source for cell replacement.
Their transdifferentiation can be achieved by triggering epigenetic remodeling
through e. g. post-translational modification of histones. Valproic
acid, a branched-chain saturated fatty acid with histone deacetylase inhibitor
activity, was linked to the expression of key transcription factors of
pancreatic lineage in epithelial cells and insulin transcription. However, the
potential of valproic acid to cause cellular reprogramming is not fully
understood. To shed further light on it we employed next-generation RNA
sequencing, real-time PCR, and protein analyses by ELISA and western blot, to
assess the impact of valproic acid on transcriptome and function of
Panc-1-cells. Our results indicate that valproic acid has a significant impact
on the cell cycle, cell adhesion, histone H3 acetylation, and metabolic pathways
as well as the initiation of epithelial-mesenchymal transition through
acetylation of histone H3 resulting in α-cell-like characteristics. We
conclude that human epithelial pancreatic cells can be transdifferentiated into
cells with endocrine properties through epigenetic regulation by valproic acid
favoring an α-cell-like phenotype.
Therapie der Sialorrhoe mit Botulinumtoxin – ein
Update
Authors: Jost Wolfgang H. , Bäumer Tobias , Berweck Steffen , Laskawi Rainer , Spittau Björn , Steffen Armin , Winterholler Martin
Published: April 2022

Die größten Speicheldrüsen sind die paarigen Gl. parotis
und Gl. submandibularis. Der erwachsene Mensch produziert
1–1,5 l Speichel am Tag, die er regelmäßig
abschluckt. Die häuﬁgste Ursache eines vermehrten
Speichelﬂusses mit einer Ansammlung von Speichel im Mund und
Ausﬂuss (Sialorrhoe) ist eine Störung der Schluckfunktion.
Seltener kann auch eine vermehrte Speichelsekretion, z. B.
medikamentös bedingt, die Ursache sein. Eine Sialorrhoe
beeinträchtigt die Lebensqualität erheblich und ist oft auch
sozial stigmatisierend. Die Therapie umfasst konservative Maßnahmen wie
die funktionelle Dysphagietherapie, orale oder transdermale Applikation von
Anticholinergika sowie, in ausgewählten Fällen, invasive
Therapien wie Bestrahlungen und Operationen. Seit 20 Jahren wird auch die lokale
Injektion von Botulinumtoxin in die Speicheldrüsen erfolgreich
therapeutisch eingesetzt. Durch die Zulassung von IncobotulinumtoxinA
für die Behandlung von Kindern und Erwachsenen darf diese
Maßnahme als Therapie der Wahl bei chronischer Sialorrhoe angesehen
werden. Die Ergebnisse der Zulassungsstudien zeigen bei Kindern wie auch
Erwachsenen eine hohe Effektivität und gute Verträglichkeit der
Injektionsbehandlung.
Behandlung der Sialorrhoe mit Botulinum Neurotoxin Typ A –
Konsentierte Praxisempfehlungen für Kinder und
Erwachsene
Authors: Jost Wolfgang H. , Bäumer Tobias , Bevot Andrea , Birkmann Ulrich , Buhmann Carsten , Grosheva Maria , Guntinas-Lichius Orlando , Mlynczak Ute , Paus Sebastian , Pflug Christina , Schröder Sebastian , Steffen Armin , Wilken Bernd , Berweck Steffen
Published: April 2022

Sialorrhoe, ein unkontrollierter, übermäßiger
Speichelfluss aus dem Mund und in den Schlund, tritt als Begleitsymptom bei
verschiedenen, v. a. neurologischen Erkrankungen im Kindes- und
Erwachsenenalter auf. Mit IncobotulinumtoxinA (Xeomin, IncoBoNT/A,
Merz Pharmaceuticals GmbH) steht seit 2019 ein zugelassenes Medikament
für die Behandlung der Sialorrhoe zur Verfügung.
Indikationsstellung, mögliche Therapieziele, Praxis der Behandlung und
Management in besonderen Behandlungssituationen bilden den Schwerpunkt dieser
konsentierten Praxis-Empfehlungen, die in interdisziplinärer
Zusammenarbeit erfahrener Anwender entwickelt wurden. Ziel ist, den Zugang zur
Therapie zu erleichtern und einen Beitrag zu einer qualifizierten
Botulinumtoxin-Therapie zu leisten.
Metabolic Status Modulates Choroidal Thickness – A Possible
Early Indicator for Diabetic Eye Complications?
Authors: Meyhöfer Svenja , Wilms Britta , Chamorro Rodrigo , Knaak Armin , Pappa Eleni , Schulz Agnetha S. , Pagels Anna-Josephin , Schröder Maria , Kaluzny Neele , Grein Hans-Jürgen , Meyhöfer Sebastian M.
Published: April 2022

Objective To investigate the impact of metabolic status on choroidal
thickness (ChT) in healthy subjects, patients with obesity, and type 2
diabetes.

Design and Methods Fasting blood glucose, insulin, insulin-like growth
factor-1 (IGF-1), and ChT measured by optical coherence tomography were assessed
in healthy normal-weight (n=17), obese participants (n=20), and
obese participants with T2D (n=16).

Results ChT increased in obese participants and obese participants with
T2D as compared to healthy normal-weight participants (P<0.0001). A
negative correlation was observed between IGF1 and ChT
(r=−0.268, P=0.050) for all cohorts. Furthermore, body
mass index (BMI; R2=0.209; P=0.002;
beta=0.388) and model assessment-estimated insulin resistance (HOMA-IR;
R2=0.074; P=0.015; beta=0.305) were
independent variables of ChT, explaining 20.9 and 7.4% of its variance
(both p<0.016), whereas age, sex, and IGF-1 were not significant
confounders of ChT (p>0.975).

Conclusion ChT is associated with metabolic characteristics,
i. e., BMI and HOMA-IR. Due to the key role of choroidal function in
retinal physiology, future studies are needed to evaluate whether metabolic
traits, ChT, and potential metabolic eye complications are mechanistically
linked.
Knowledge, Attitude, and Practices of Parents toward Pediatric Dental Radiography
Authors: Sreenivasan Sanjna K. , Lolayekar Nikita , Sheth Priyal , Rao Dipasha
Published: April 2022

Background Pediatric dental radiography is a field with numerous uses as well as concerns regarding radiation safety. This study was undertaken to assess the knowledge that parents have regarding the same. This questionnaire survey was conducted with the aim of assessing the knowledge, attitude, and practices of parents toward pediatric dental radiography.

Material and Methods In total, 280 questionnaires were answered by parents of children visiting the Pediatric Dental Department. The first 10 questions served to evaluate the knowledge and attitude of parents toward pediatric dental radiography. The last three questions were designed to assess the practices of parents in relation to dental radiography and protective gear. The answers were collected and analyzed.

Results From the survey it was seen that most parents were aware that the harmful effects from dental radiography were minimal (51%). A fairly significant number of parents lacked the knowledge regarding the harmful effects of dental radiography in children compared to adults (63%), in comparison to the harmful effects from cell phones (66%) and in comparison to harmful effects of medical radiography (42%). A fair number of parents seemed to be aware of the detrimental cumulative nature (47%) of radiation. It was found that a large number of parents do not ask for an explanation regarding the need for the dental radiograph for their children before the dental treatment (50%). Most parents (64%) were not aware of the availability of protective gear and very few (16%) requested for it.

Conclusion The parents considered in this study had appreciable knowledge and a positive attitude toward dental radiography. However, a significant lack of knowledge regarding protective gear used for dental radiography among these parents was identified from this study.
Ultra-high temperature video extensometer: System development and experimental validation
Authors: Yu Liping , Ren Fuguo , Zhang Xiaoying , Pan Bing
Published: April 2022

The video extensometer has been widely advocated for tensile/compressive strain measurement in high-temperature material testing due to its advantages of non-contact measurement, wider measuring range, and larger applicable temperature over traditional clip-on mechanical extensometers. However, existing video extensometers, despite the adoption of active imaging devices, cannot adapt to the rapidly changing thermal radiation from the heated sample and surrounding heating elements during the high-temperature tests. This is because due to the significantly intensified thermal radiation, the decorrelated images degrade the measuring accuracy or even destroy the analysis. To address this problem, we developed an ultra-high temperature video extensometer that can automatically adjust the camera exposure time for reliable thermal strain measurement. Based on the pre-established image quality evaluation criteria, the camera will choose an appropriate exposure time according to the detected thermal radiation within the region of interest, thus ensuring high-quality images for real-time strain measurement. Static tests of tungsten–molybdenum alloy samples at different temperatures were performed to evaluate the noise level of the established ultra-high temperature video extensometer. The effectiveness and accuracy of the developed ultra-high temperature video extensometer were validated through the tensile tests of tungsten–copper, tungsten–potassium, and tungsten–molybdenum alloy samples at high temperatures up to 2000 °C.
Modeling and simulation of interstitial fluid flow around an osteocyte in a lacuno-canalicular network
Authors: Zhu Luoding , Barber Jared , Zigon Robert , Na Sungsoo , Yokota Hiroki
Published: April 2022

Experiments have shown that external mechanical loading plays an important role in bone development and remodeling. In fact, recent research has provided evidence that osteocytes can sense such loading and respond by releasing biochemical signals (mechanotransduction, MT) that initiate bone degradation or growth. Many aspects on MT remain unclear, especially at the cellular level. Because of the extreme hardness of the bone matrix and complexity of the microenvironment that an osteocyte lives in, in vivo studies are difficult; in contrast, modeling and simulation are viable approaches. Although many computational studies have been carried out, the complex geometry that can involve 60+ irregular canaliculi is often simplified to a select few straight tubes or channels. In addition, the pericellular matrix (PCM) is usually not considered. To better understand the effects of these frequently neglected aspects, we use the lattice Boltzmann equations to model the fluid flow over an osteocyte in a lacuno-canalicular network in two dimensions. We focus on the influences of the number/geometry of the canaliculi and the effects of the PCM on the fluid wall shear stress (WSS) and normal stress (WNS) on an osteocyte surface. We consider 16, 32, and 64 canaliculi using one randomly generated geometry for each of the 16 and 32 canaliculi cases and three geometries for the 64 canaliculi case. We also consider 0%, 5%, 10%, 20%, and 40% pericellular matrix density. Numerical results on the WSS and WNS distributions and on the velocity field are visualized, compared, and analyzed. Our major results are as follows: (1) the fluid flow generates significantly greater force on the surface of the osteocyte if the model includes the pericellular matrix (PCM); (2) in the absence of PCM, the average magnitudes of the stresses on the osteocyte surface are not significantly altered by the number and geometry of the canaliculi despite some quantitative influence of the latter on overall variation and distribution of those stresses; and (3) the dimensionless stress (stress after non-dimensionalization) on the osteocyte surface scales approximately as the reciprocal of the Reynolds number and increasing PCM density in the canaliculi reduces the range of Reynolds number values for which the scaling law holds.
Crack quasi-healing in films of vertically aligned 1D nanostructures: Impact of compliance in a 1D geometry
Authors: Pauchard Ludovic , Giorgiutti-Dauphiné Frédérique , McIlroy David
Published: April 2022

We study nanostructured films made of helical nanowires and nanosprings, which provide remarkable mechanical behavior. When subjected to wetting and drying processes, these films crack like most coatings. However, beyond the great ability of these films to shrink, the cracks partially close when these films are no longer mechanically stressed. While for conventional coatings about 20% of the crack opening is relieved, more than 80% of the crack opening is relieved in films of nanosprings when the film is unloaded. We show here that this quasi-reversibility is related to (i) the high compliance of the material, (ii) the low energy consumed by plasticity, and (iii) the high deformability of the film components, e.g., the nanosprings. These results are compared to the case of usual particulate films.
Pressure-induced evolution of structure and electronic property of GeP
Authors: Tao Yajun , Xie Shiyu , Lu Tenglong , Hu Chuansheng , Liu Hengjie , Zhang Huanjun , Cheng Xuerui , Liu Miao , Qi Zeming
Published: April 2022

The monoclinic semiconductor GeP is a new class of Group IV–V layered material, and it shows attractive anisotropic optical and electronic properties. In this paper, we investigate the structural and electronic evolution of layered GeP under pressure, using in situ x-ray diffraction, Raman and infrared spectra, and the density functional theory. All characterization methods reveal that the pressure causes two obvious phase changes. One isostructural transition is observed around 6 GPa. Above 21 GPa, another crystalline-to-amorphous transformation is obtained. It is worth noting that the high-pressure amorphous state can be retained at ambient conditions after the pressure is released. In addition, the pressure-induced red-shift of absorbance edge suggests its bandgap decreases with pressure. This result indicates that pressure has a significant effect on GeP. Meanwhile, it also provides a method for obtaining amorphous GeP, which is of interest to the energy storage community as it is a potential anode material for lithium-ion batteries.
Machine learning for a finite size correction in periodic coupled cluster theory calculations
Authors: Weiler Laura , Mihm Tina N. , Shepherd James J.
Published: April 2022

We introduce a straightforward Gaussian process regression (GPR) model for the transition structure factor of metal periodic coupled cluster singles and doubles (CCSD) calculations. This is inspired by the method introduced by Liao and Grüneis for interpolating over the transition structure factor to obtain a finite size correction for CCSD [K. Liao and A. Grüneis, J. Chem. Phys. 145, 141102 (2016)] and by our own prior work using the transition structure factor to efficiently converge CCSD for metals to the thermodynamic limit [Mihm et al., Nat. Comput. Sci. 1, 801 (2021)]. In our CCSD-FS-GPR method to correct for finite size errors, we fit the structure factor to a 1D function in the momentum transfer, G. We then integrate over this function by projecting it onto a k-point mesh to obtain comparisons with extrapolated results. Results are shown for lithium, sodium, and the uniform electron gas.
Unsteady transport and two-phase binding of a drug in an atherosclerotic artery
Authors: Biswas Sayantan , Sarifuddin  , Mandal Prashanta Kumar
Published: April 2022

To quantify the biology and physical understanding of endovascular drug delivery, a mathematical model that accounts for the two-phase binding of drug molecules in a diseased patient-specific artery has been developed. Using an image segmentation technique, the edges of the computational domain have been successfully extracted from an asymmetric intravascular ultrasound longitudinal image. The flow inside the porous tissue is described by the Brinkman model, and the luminal flow is Newtonian. At the lumen–tissue interface, an irreversible uptake kinetics for the injected drug from the luminal side into the tissue is taken into account. Furthermore, the drug's two-phase binding process, namely, the nonspecific binding caused by the drug's trapping in the extracellular medium (ECM-bound) and the specific binding caused by the interaction between drug molecules and receptors (REC-bound), has been considered. The Marker and Cell method has been leveraged to solve the governing equations numerically. Spatiotemporal variations of free drug, ECM-bound drug, and REC-bound drug are examined thoroughly for varying absorption parameter. Simulated results reveal that the interstitial flow amplifies drug distribution, retention, and delivery effectiveness, but flow separation downstream of the constriction reduces transmural flux. Concomitantly, the larger the absorption parameter, the higher the tissue content and effectiveness; nevertheless, significantly, larger absorption parameter values do not necessarily suggest improved delivery effectiveness. A thorough sensitivity analysis was carried out to predict the effects of some of the parameters involved.
Thermocapillary patterning of non-Newtonian thin films
Authors: Mohammadtabar Ali , Nazaripoor Hadi , Riad Adham , Hemmati Arman , Sadrzadeh Mohtada
Published: April 2022

Deformation of thin viscous liquid films exposed to a transverse thermal gradient results in Bénard–Marangoni instability, which would lead to the formation of micro- and nano-sized features. Linear and nonlinear analyses are performed to investigate the thermally induced pattern formation in shear thinning and shear thickening liquid films. The so-called thin film (TF) equation is re-derived to include viscosity variations using the power-law (PL) model. The characteristic wavelength for the growth of instabilities is found using a linear stability analysis of the PL-TF equation. A finite-difference-based discretization scheme and adaptive time step solver are used to solve the PL-TF equation for the nonlinear numerical model. The results show that the rheological property affects the timescale of the process and the size and final shape of the formed features. The fastest growth pillar reaching the top substrate in a shear thickening fluid is shorter than both the shear thinning and the Newtonian fluid cases. Moreover, morphological changes between patterns of shear thinning and shear thickening fluids are correlated with local viscosity variations. The number of formed pillars considerably increases with the increasing flow behavior index. The existing model also predicts the formation of pillars and bicontinuous structures at very low and high filling ratios.
Rheology and structure of a suspension of deformable particles in plane Poiseuille flow
Authors: Audemar Vassanti , Podgorski Thomas , Coupier Gwennou
Published: April 2022

We present an experimental study of the rheology and structure of a confined suspension of deformable particles flowing in a quasi-two-dimensional Poiseuille flow. Thanks to a precise microfluidic viscosimetry technique combined with measurements of concentration profiles, our study provides the first experimental confirmation with three-dimensional particles of a strong relationship between structuring effects and rheology, previously only reported in numerical simulations of purely two-dimensional systems. In conditions where strong structuring effects take place due to confinement, the evolution of the effective viscosity with particle concentration (here, red blood cells) shows a remarkable succession of ranges of rapid growth and plateaus that are associated with qualitative transitions in the structure of the suspension.
Prediction of acoustic pressure of the annular combustor using stacked long short-term memory network
Authors: Lyu Zengyi , Fang Yuanqi , Zhu Zhixin , Jia Xiaowei , Gao Xianzhi , Wang Gaofeng
Published: April 2022

This paper proposes a data-driven method named stacked long short-term memory (S-LSTM) for predicting the future growth of acoustic pressure signals to detect precursors of combustion instability. The application of S-LSTM is investigated using the acoustic pressure data obtained from an annular combustor. The S-LSTM method is compared with the support vector machine (SVM) in terms of the predictive performance and also provides detailed insights into the influence of input choice by interpreting the results of S-LSTM. It is demonstrated that S-LSTM can effectively predict future pressure signals with a better error control performance compared to the SVM method. Furthermore, the feasibility of the S-LSTM in the thermoacoustic instability problem is verified using acoustic pressure data obtained from industrial combustion tests with a low-emission aero-engine. It is expected that the implementation of S-LSTM provides an early prediction solution to avoid thermoacoustic instability.
Effect of surfactants on droplet generation in a microfluidic T-junction: A lattice Boltzmann study
Authors: Zhang Jinggang , Zhang Xitong , Zhao Wei , Liu Haihu , Jiang Youhua
Published: April 2022

Droplet generation in a T-junction with surfactants is simulated using our recently developed lattice Boltzmann method. The method is first used to explore the effect of surfactant concentration ψb on droplet generation. As ψb increases, droplet generation tends to shift from squeezing to dripping regime and then to jetting regime. In the clean system, the upstream pressure varies almost periodically with time. However, in the surfactant-laden system, the upstream pressure no longer varies periodically but overall increases with time for droplet generation in squeezing and dripping regimes. This is because the addition of surfactants results in an additional pressure drop between the front and rear of the generated droplet. Then, droplet generation in both clean and surfactant-laden systems is compared to explore the surfactant role under different values of the capillary number Ca. In either clean or surfactant-laden system, the pressure upstream of the junction rapidly decreases as Ca increases. In the presence of surfactants, the upstream pressure overall increases with time for droplet generation in squeezing and dripping regimes, but the increased amplitude decreases with Ca. Finally, we establish the phase diagrams describing how the droplet generation regime varies with flow rate ratio and Ca in both clean and surfactant-laden systems. It is found that the addition of surfactants reduces the critical capillary number distinguishing squeezing from dripping and the critical capillary number distinguishing dripping from jetting.
Statistically invariant eddy viscosity models
Authors: Klingenberg Dario , Oberlack Martin
Published: April 2022

We presently generalize existing two-equation Reynolds-averaged Navier–Stokes models by using recent advances in our understanding of the Lie symmetries of governing turbulence. The motivation for this and the necessary steps are laid out using the conventional terminology of turbulence modeling, without requiring deep knowledge about the mathematical concept of symmetries. For illustration purposes, these steps are applied to the standard k–ε model and the k–ω model. The so-modified k–ε model is applied to a wide range of canonical flows. For all of them, it is shown to match or even improve the performance of its classical counterpart and is, thus, shown to be more general than the original k–ε model.
Application of siligraphene sheets to detect COVID-19 through volatile organic biomarkers in exhaled breath of humans: A first-principles study
Authors: Majidi Roya
Published: April 2022

The possibility of using siligraphene sheets to detect volatile organic biomarkers in the exhaled breath of humans with COVID-19 is studied. Heptanal, octanal, and nonanal are identified as the prominent biomarkers of COVID-19. Adsorption of these molecules on SiC and SiC7 sheets is examined by density functional theory. The adsorption energies indicate that the considered sheets could be proper materials to use as reusable sensors. SiC and SiC7 exhibit semiconductor properties. The energy bandgap of SiC7 reduces more drastically than that of SiC with heptanal, octanal, and nonanal adsorption. Thus, the electronic properties of SiC7 are sensitive to the adsorption of the considered molecules. It is also shown that physisorption of the water molecule has no considerable effect on the bandgap of SiC7. Thus, SiC7 is a suitable sensor for use in humid conditions like an exhaled breath of humans to diagnose COVID-19.
Gene evolutionary trajectories in
Mycobacterium tuberculosis
reveal temporal signs of selection
Authors: Chiner-Oms Álvaro , López Mariana G. , Moreno-Molina Miguel , Furió Victoria , Comas Iñaki
Published: April 2022

Genetic differences between different
Mycobacterium tuberculosis
complex (MTBC) strains determine their ability to transmit within different host populations, their latency times, and their drug resistance profiles. Said differences usually emerge through de novo mutations and are maintained or discarded by the balance of evolutionary forces. Using a dataset of ∼5,000 strains representing global MTBC diversity, we determined the past and present selective forces that have shaped the current variability observed in the pathogen population. We identified regions that have evolved under changing types of selection since the time of the MTBC common ancestor. Our approach highlighted striking differences in the genome regions relevant for host–pathogen interaction and, in particular, suggested an adaptive role for the sensor protein of two-component systems. In addition, we applied our approach to successfully identify potential determinants of resistance to drugs administered as second-line tuberculosis treatments.
Generation of double Holliday junction DNAs and their dissolution/resolution within a chromatin context
Authors: Ho Han N. , West Stephen C.
Published: April 2022

Significance

We devised a method involving DNAzyme self-cleavage for the preparation of DNA molecules containing double Holliday junctions (dHJs) that are separated by 746 bp. The DNAs can be prepared in large amounts suitable for in vitro analysis of enzymes required for the processing of recombination intermediates. We show that the dHJ DNA is dissolved efficiently by the BLM–TopIIIα–RMI1–RMI2 (BTRR) complex to produce noncrossover products, whereas nucleolytic resolution by GEN or SMX results in both crossover and noncrossover products. Following nucleosome assembly, the chromatinized dHJ structures are preferentially dissolved by BTRR. These new Holliday junction substrates will provide a valuable resource for the mechanistic analyses of the way in which recombination intermediates are processed.
Heart failure in mice induces a dysfunction of the sinus node associated with reduced CaMKII signaling
Authors: Xue Jian-Bin , Val-Blasco Almudena , Davoodi Moran , Gómez Susana , Yaniv Yael , Benitah Jean-Pierre , Gómez Ana María
Published: April 2022

Dysfunction of the sinoatrial node (SAN), the natural heart pacemaker, is common in heart failure (HF) patients. SAN spontaneous activity relies on various ion currents in the plasma membrane (voltage clock), but intracellular Ca2+ ([Ca2+]i) release via ryanodine receptor 2 (RYR2; Ca2+ clock) plays an important synergetic role. Whereas remodeling of voltage-clock components has been revealed in HF, less is known about possible alterations to the Ca2+ clock. Here, we analyzed [Ca2+]i handling in SAN from a mouse HF model after transverse aortic constriction (TAC) and compared it with sham-operated animals. ECG data from awake animals showed slower heart rate in HF mice upon autonomic nervous system blockade, indicating intrinsic sinus node dysfunction. Confocal microscopy analyses of SAN cells within whole tissue showed slower and less frequent [Ca2+]i transients in HF. This correlated with fewer and smaller spontaneous Ca2+ sparks in HF SAN cells, which associated with lower RYR2 protein expression level and reduced phosphorylation at the CaMKII site. Moreover, PLB phosphorylation at the CaMKII site was also decreased in HF, which could lead to reduced sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) function and lower sarcoplasmic reticulum Ca2+ content, further depressing the Ca2+ clock. The inhibition of CaMKII with KN93 slowed [Ca2+]i transient rate in both groups, but this effect was smaller in HF SAN, consistent with less CaMKII activation. In conclusion, our data uncover that the mechanism of intrinsic pacemaker dysfunction in HF involves reduced CaMKII activation.
Phase-Locking Diffusive Skin Effect
Authors: Cao Pei-Chao , Peng Yu-Gui , Li Ying , Zhu Xue-Feng
Published: April 2022

We explore the exceptional point (EP) induced phase transition and amplitude/phase modulation in thermal diffusion systems. We start from the asymmetric coupling double-channel model, where the temperature field is unbalanced in the amplitude and locked in the symmetric phase. By extending into the one-dimensional tight-binding non-Hermitian lattice, we study the convection-driven phase locking and the asymmetric-couplinginduced diffusive skin effect with the high-order EPs in static systems. Combining convection and asymmetric couplings, we further show the phase-locking diffusive skin effect. Our work reveals the mechanism of controlling both the amplitude and phase of temperature fields in thermal coupling systems and has potential applications in non-Hermitian topology in thermal diffusion.
Arm locking performance with the new LISA design
Authors: Ghosh Sourath , Sanjuan Josep , Mueller Guido
Published: April 2022

The laser interferometer space antenna (LISA) is a future space-based gravitational wave detector designed to be sensitive to sources radiating in the low frequency regime (0.1 mHz to 1 Hz). LISA’s interferometer signals will be dominated by laser frequency noise which has to be suppressed by about seven orders of magnitude using an algorithm called time delay interferometry (TDI). Arm locking has been proposed to reduce the laser frequency noise by a few orders of magnitude to reduce the potential risks associated with TDI. In this paper, we present an updated performance model for arm locking for the new LISA mission using 2.5 Gm arm lengths, the currently assumed clock noise, spacecraft motion based on LISA Pathfinder data and shot noise. We also update the Doppler frequency pulling estimates during lock acquisition.
A stability result for the identification of a permeability parameter on Navier–Stokes equations
Authors: Aguayo Jorge , Osses Axel
Published: April 2022

In this work, we present a stability result for the inverse problem of recovering a smooth scalar permeability parameter given by the Brinkman’s law applied to the steady Navier–Stokes equations from local observations of the fluid velocity on a fixed domain. In comparison with (Choulliet al2013Appl. Anal.922127–43), we prove a logarithmic estimate under weaker assumptions, since our proof is based in a strategy that does not require pressure observations. This kind or result are useful for inverse problems in soft tissue elastography (see Honarvaret al2012Phys. Med. Biol.575909–27). Finally, we present some numerical tests that validate our theoretical results.
A multi-functional frequency selective polarization converter based on substrate integrated waveguide cavities
Authors: Ren Yan , Lin Hai , Tang Rongxin , Wu Yanjie , Zhou Rui , Xiong Jie
Published: April 2022

In this paper, a multi-functional frequency selective polarization converter (FSPC) based on the substrate integrated waveguide cavities (SIWC) is presented. The proposed structure is based on a circular shape SIWC with orthogonal rectangular slots on the top/bottom layer of each unit cell. The neighboring SIWC are connected to each other by metalized vias which formed a shared diamond shape cavity. Two cross shape slots serve as additional input and output channel for the shared SIW cavity. The novel design introduces more functions to the device. When the device acts as a frequency selective surface, it provide two transmission window around 8.52 and 13 GHz. It can also realize cross-polarization conversion between TM and TE polarized waves from 15.87 to 17.01 GHz as well as narrowband polarization conversion around 10.33 GHz. The working mechanism of proposed design has been explained through the analysis of the surface current distribution. In order to verify the performance of the design, a prototype was manufactured and measured, the simulated and measured results are highly consistent with each other.
Diagnostic study of capacitively coupled neon rf plasma with traces of O2/H2 at intermediate pressure
Authors: Baghel S S , Şahin N , Agrawal A , Gangwar R K , Tanışlı M , Srivastava R
Published: April 2022

In this work, we have performed the non-invasive diagnostic study of capacitively coupled Ne–O2/H2 mixture plasma through the optical emission spectroscopy (OES) coupled with a suitable collisional radiative (CR) model. Capacitively coupled neon radio-frequency (rf) discharge (flowing downstream) with small admixture of O2/H2 have been generated in a vacuum chamber using 13.56 MHz rf signal and 120 W power supply. Keeping O2 and H2 flow rates fixed at 0.01 and 0.015 LPM respectively, the neon flow rate has been varied as 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8 LPM to obtain different mixture concentration of Ne–O2 and Ne–H2 discharge. The pressure in the chamber has been observed in intermediate range (∼500–25 000 Pa) for different mixture concentrations. OES measurements are recorded at various operating conditions in the wavelength range from 200 to 1200 nm. To extract the information of plasma parameters from the OES measurements, a comprehensive fine-structure resolved CR model has been developed. In the diagnostic process, five intense Ne–I emission lines at 594.48, 607.43, 633.44, 638.30, 703.24 nm are used. The CR model considers all the important processes i.e. electron impact excitation, electron impact de-excitation, radiative decay, ionization, two–three body recombination, and diffusion. The quenching process of 1s (1s5,1s4,1s3) levels of neon by the O2/H2 molecule has been included in the model. The radiative transitions from the upper levels to the ground state (1S0) as well as to the 1s levels of neon are corrected for self-absorption. The electron temperature (T
e) and electron density (n
e) of the plasma have been extracted for all the mixture concentrations of Ne–O2 and Ne–H2. Also, with the different mixture concentrations of O2/H2 in neon discharge, the variation of population of metastable levels (1s5, 1s3) of neon as well as intensities of 656.28 nm of hydrogen and 777.4 nm of oxygen lines have been reported and discussed.
Determining spin-orbit torque in a single ferrimagnetic film without heavy metal via spin-torque ferromagnetic resonance
Authors: Wang Junshuai , Li Chaozhong , Liu Fufu , Jiang Changjun
Published: April 2022

We report spin-orbit torque (SOT) in a single ferrimagnetic (FIM) GdFeCo alloy based on spin-torque ferromagnetic resonance (ST FMR). Thickness-dependent anomalous Hall resistance shows a bulk perpendicular magnetic anisotropy, which lead double peaks of ST FMR spectra at a larger thickness of 50 nm. Oblique-angle-dependent ST FMR is performed to study SOT, and the spin torque efficiency in the y axis is evaluated. This phenomenon is explained by the relationship between SOT and saturation magnetization. This finding provides an alternative method to modulate SOT in a single ferrimagnetic spintronic device.