bluuebunny/crossref_metadata_2025 huggingface dataset:
Do Antiangiogenics Promote Clot Instability? Data from the TESEO Prospective Registry and Caravaggio Clinical Trial
Authors: Carmona-Bayonas Alberto , Verso Melina , Sánchez Cánovas Manuel , Rubio Pérez Jaime , García de Herreros Marta , Martínez del Prado Purificación , Fernández Pérez Isaura , Quintanar Verduguez Teresa , Obispo Portero Berta , Pachón Olmos Vanessa , Gómez David , Ortega Laura , Serrano Moyano Marta , M. Brozos Elena , Biosca Mercedes , Antonio Rebollo Maite , Teijeira Sanchez Lucía , Hernández Pérez Carolina , David Cumplido Burón José , Martínez Lago Nieves , García Pérez Estefanía , Muñoz Langa Jose , Pérez Segura Pedro , Martínez de Castro Eva , Jimenez-Fonseca Paula , Agnelli Giancarlo , Muñoz Andrés
Published: April 2022

Background Venous thromboembolism (VTE) is a common complication in cancer patients. Much of its morbidity stems from the development of fatal pulmonary embolisms (PE). Little is known about the factors involved in clot stability, with angiogenesis possibly being implicated.

Methods The database is from the TESEO prospective registry that recruits cancer patients with VTE from 41 Spanish hospitals. Independent validation was conducted in a cohort from the Caravaggio trial. The objective is to evaluate the association between exposure to antiangiogenic therapies and the PE/VTE proportion in oncological patients.

Results In total, 1,536 subjects were evaluated; 58.4% (n = 894) had a PE and 7% (n = 108) received antiangiogenic therapy (bevacizumab in 75%). The PE/VTE proportion among antiangiogenic-treated individuals was 77/108 (71.3%) versus 817/1,428 (57.2%) among those receiving other alternative therapies (p = 0.004). The effect of the antiangiogenics on the PE/VTE proportion held up across all subgroups except for active smokers or those with chronic obstructive pulmonary disease. Exposure to antiangiogenics was associated with increased PEs, odds ratio (OR) 2.27 (95% CI, 1.42–3.63). In the Caravaggio trial, PE was present in 67% of the individuals treated with antiangiogenics, 50% of those who received chemotherapy without antiangiogenic treatment, and 60% without active therapy (p = 0.0016).

Conclusion Antiangiogenics are associated with increased proportion of PE in oncological patients with VTE. If an effect on clot stability is confirmed, the concept of thrombotic risk in cancer patients should be reconsidered in qualitative terms.
DBU- and DABCO-Promoted Selective Access to 2,5-Diarylnitrobenzoates and Cyclohexenones via One-Pot Reactions
Authors: Samanta Sampak , Rathor Shikha Singh , Majee Debashis
Published: April 2022

Remarkable organobase-controlled selective synthesis of a wide breadth of valuable 2,5-diaryl-4-nitrobenzoates and 1-hydroxy-4-oxocyclohexencarboxylates bearing a tetrasubstituted stereogenic carbon is reported. This one-pot cyclization reaction operates between a bunch of 3-nitroallylarenes and β,γ-unsaturated α-ketocarbonyls by carefully choosing DBU or DABCO as an organobase under aerobic conditions. Notably, as a nucleophilic base, DABCO favors the Nef reaction over the dehydration–aerial oxidation process, aiming for unexpected cyclohexanone architectures. Moreover, this operationally simple technique holds a few positive qualities: good yields with diastereoselectivities (dr ≤ 91:9), broad substrate scope, no added oxidant, excellent functional group compatibility, 100% carbon-economical, etc. Furthermore, the obtained 4-nitrobenzoate framework has been utilized for the synthesis of a range of valuable compounds such as 2-phenylcarbazole-3-carboxylate, 3-bromoaniline derivative, and 2,5-diphenylbenzoic acid, among others.
Accelerated Decomposition of Potassium Permanganate in Ferrocenium Ion as Ferrocenium-Doped Manganese(IV) Oxide for Selective Oxidation of Alcohols
Authors: Chumkaeo Peerapong , Poonsawat Thinnaphat , Yunita Isti , Temnuch Natcha , Meechai Titiya , Kumpan Nuttapong , Khamthip Achjana , Chuaitammakit Laksamee Chaicharoenwimolkul , Chairam Sanoe , Somsook Ekasith
Published: April 2022

Ferrocenium-doped manganese(IV) oxide (Fc+/MnO2) was synthesized through accelerated decomposition of KMnO4 in the presence of ferrocenium ion (Fc+) generated by concentrated sulfuric acid. The corresponding catalysts enabled highly efficient oxidation of alcohols with aldehyde or ketone.
Potassium tert-Butoxide Facilitated Amination of Carboxylic Acids with N,N-Dimethylformamide
Authors: Zhang Jing , Huang Yuanjing
Published: April 2022

Herein a practical and efficient potassium tert-butoxide (KO
t
Bu)-facilitated amination of carboxylic acids with N,N-dimethylamine is described. In the presence of catalytic amount of KO
t
Bu, a variety of aliphatic and aromatic carboxylic acids are transformed to N,N-dimethylamides using DMF as the dimethylamine reagent with the assistance of trimethylacetic anhydride. The applicability of this protocol is demonstrated by late-stage dimethylamidation of complex drug molecules. A plausible reaction mechanism involving KO
t
Bu-facilitated in situ amine generation from formamide decomposition and anhydride-mediated condensation is proposed on the basis of mechanistic investigations.
Improving Outcomes through a Neonatal Abstinence Syndrome Collaborative in Maryland
Authors: DiPietro Bonnie , Silcox Kristin , Rost James , Woods Lee S. , Edwards Erika M. , Buus-Frank Madge E. , Horbar Jeffrey D. , Hudak Mark L.
Published: April 2022

Objectives A statewide Maryland Perinatal Neonatal Quality Collaborative, facilitated by the Maryland Patient Safety Center (MPSC), identified the three specific, measurable, attainable, relevant, and time-limited (SMART) aims to improve outcomes of neonatal abstinence syndrome (NAS) care as follows: (1) to reduce hospital length of stay (LOS), (2) to reduce interhospital transfers, and (3) to reduce 30-day readmission rates of infants with NAS.

Study Design The Maryland collaborative developed a bundle of best practices for care of infants with NAS. MPSC partnered with Vermont Oxford Network (VON) to utilize the VON NAS toolkit and provided its standardized NAS educational curriculum to address the three objectives for participating birthing hospitals. Efforts began in quarter 4 (Q4) of 2016 and continued for 2 years. Thirty-one of Maryland's 32 delivery hospitals (97%) participated in the 2-year collaborative. Additionally, one specialty pediatric hospital with an NAS unit participated in the group learnings. Participating facilities implemented components of the MPSC NAS bundle and provided their staff caring for infants with NAS and their mothers access to the VON standardized educational curriculum. MPSC partnered with VON to conduct two audits of implementation of policies and procedures in Q1 of 2016 and Q3 of 2018. The Maryland Department of Health supplied quarterly aggregate hospital information on LOS, interhospital transfers, and 30-day readmissions of infants with a discharge diagnosis of the International Classification of Disease, 10th Revision (ICD-10), P96.1.

Results Among term infants with NAS with total hospital stay greater than 5 days, we observed a nonsignificant reduction in both mean and median LOS of 1.5 days. In this same group, the rate of interhospital transfers fell significantly from 20.1% in 2016 to 13.8 and 11.0% in 2017 and 2018, respectively.

Conclusion The best practice bundle created by the Maryland collaborative was associated with a reduction in the percentage of infants with NAS who required interhospital transfer, thereby reducing family disruption.

Key Points
Anticipatory Strategy Training: Implications for the Postlingually Hearing-Impaired Adult
Authors: Rubinstein Adrienne , Cherry Rochelle , Hecht Perri , Idler Carrie
Published: April 2022

The present study was designed to determine if speech recognition performance will improve after subjects prepare for an unfamiliar communication situation as opposed to a familiar one. Forty-five normal-hearing subjects were divided into three groups: one trained using a well-known fairytale, one trained using an obscure fable, and one without training. Post-training, all groups performed similarly when tested on the familiar tale. When test material involved the unfamiliar fable, only the group trained on that material obtained significantly better scores than the other groups. Results support teaching clients that increasing their knowledge of upcoming unfamiliar events can improve subsequent speech recognition.

Abbreviations: ANOVA = analysis of variance
Diversity via datafication? Digital patient records and citizenship for sexuality and gender diverse people
Authors: Davis Mark D. M. , Schermuly Allegra , Smith Anthony K. J. , Newman Christy
Published: April 2022

In 2018, the Australian Government adopted an ‘opt-out’ strategy to increase participation in My Health Record (MHR), the national digital patient record system. Opt out was rationalised through discourse on the universal right to health. Media controversy ensued due to privacy fears, security and commercial exploitation of patient information. LGBT community organisations warned that people with complex health needs should consider their privacy and legal situation when deciding whether or not to opt out of MHR. With reference to the health needs of sexuality and gender diverse people, we examine MHR’s rights universalism, possessive individualism, and state-based rationalisation of health governance. MHR hails all but no-one in particular, erasing diversity and straightwashing data medicine. It is a technological solution to state-based imperatives for health governance, an emphasis that does not serve minority communities or address health needs that attract stigma and prejudice. We counterpose these effects with citizenship framings seated in critical approaches to data assemblages and sexuality and gender diversity. We suggest ways in which data medicine, of which MHR is but one example, can be made more relevant and effective for individuals and communities whose healthcare is poorly served by mainstream health systems.
Manipulations of micro/nanoparticles using gigahertz acoustic streaming tweezers
Authors: Wu Hang , Tang Zifan , You Rui , Pan Shuting , Liu Wenpeng , Zhang Hongxiang , Li Tiechuan , Yang Yang , Sun Chongling , Pang Wei , Duan Xuexin
Published: April 2022

Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets, making it universally applicable to almost all biological systems. Thin-film bulk acoustic wave (BAW) resonators operating at gigahertz (GHz) frequencies have been demonstrated to generate localized high-speed microvortices through acoustic streaming effects. Benefitting from the strong drag forces of the high-speed vortices, BAW-enabled GHz acoustic streaming tweezers (AST) have been applied to the trapping and enrichment of particles ranging in size from micrometers to less than 100 nm. However, the behavior of particles in such 3D microvortex systems is still largely unknown. In this work, the particle behavior (trapping, enrichment, and separation) in GHz AST is studied by theoretical analyses, 3D simulations, and microparticle tracking experiments. It is found that the particle motion in the vortices is determined mainly by the balance between the acoustic streaming drag force and the acoustic radiation force. This work can provide basic design principles for AST-based lab-on-a-chip systems for a variety of applications.
Machine-learning identification of the variability of mean velocity and turbulence intensity for wakes generated by onshore wind turbines: Cluster analysis of wind LiDAR measurements
Authors: Iungo G. V. , Maulik R. , Renganathan S. A. , Letizia S.
Published: April 2022

Light detection and ranging (LiDAR) measurements of isolated wakes generated by wind turbines installed at an onshore wind farm are leveraged to characterize the variability of the wake mean velocity and turbulence intensity during typical operations, which encompass a breadth of atmospheric stability regimes and rotor thrust coefficients. The LiDAR measurements are clustered through the k-means algorithm, which enables identifying the most representative realizations of wind turbine wakes while avoiding the imposition of thresholds for the various wind and turbine parameters. Considering the large number of LiDAR samples collected to probe the wake velocity field, the dimensionality of the experimental dataset is reduced by projecting the LiDAR data on an intelligently truncated basis obtained with the proper orthogonal decomposition (POD). The coefficients of only five physics-informed POD modes are then injected in the k-means algorithm for clustering the LiDAR dataset. The analysis of the clustered LiDAR data and the associated supervisory control and data acquisition and meteorological data enables the study of the variability of the wake velocity deficit, wake extent, and wake-added turbulence intensity for different thrust coefficients of the turbine rotor and regimes of atmospheric stability. Furthermore, the cluster analysis of the LiDAR data allows for the identification of systematic off-design operations with a certain yaw misalignment of the turbine rotor with the mean wind direction.
On-chip infrared photonics with Si-Ge-heterostructures: What is next?
Authors: Fischer I. A. , Brehm M. , De Seta M. , Isella G. , Paul D. J. , Virgilio M. , Capellini G.
Published: April 2022

The integration of Ge on Si for photonics applications has reached a high level of maturity: Ge photodetectors are available on the Si platform in foundry processes, and Si/Ge heterostructure multiple quantum-well photodiodes are rapidly progressing toward applications in light modulation. These successes result from decades of development of high-quality material growth and integration, which, more recently, has sparked an increasingly broad field of photonic device research based on Si/Ge heterostructures that extends from quantum cascade lasers to sensors. Here, we highlight selected recent structure and device developments as well as possible future trends that are enabled by the maturity of the SiGe material platform.
A mechanism for reduced compression in indirectly driven layered capsule implosions
Authors: Haines Brian M. , Sauppe J. P. , Albright B. J. , Daughton W. S. , Finnegan S. M. , Kline J. L. , Smidt J. M.
Published: April 2022

High-yield implosions on the National Ignition Facility rely on maintaining low entropy in the deuterium–tritium fuel, quantified by its adiabat, in order to efficiently couple energy to the hot spot through high compression of the fuel layer. We present very-high-resolution xRAGE simulation results that study the impacts of interfacial mixing and the jetting of materials due to surface defects, defects on internal interfaces, voids, and engineering features on fuel layer compression. Defects and voids are typically neglected in implosion simulations due to their small size and three-dimensional geometry. Our results showed that supersonic jets of material arise through weak spots in the shell at peak implosion velocity that prevent uniform compression of the fuel layer even when they do not introduce contaminant into the hot spot. This occurs despite maintaining low fuel entropy, since the formation of the weak spots involves nonradial displacement of fuel mass. In contrast, simulations show that fuel–ablator mixing due to interfacial instabilities has a much smaller impact on compression. We show that defects on interior interfaces of plastic capsules decrease compression by 15% to 25% and interfacial mixing between the ablator and fuel decreases compression by less than 1% for implosions with plastic or high-density carbon (HDC) ablators. For low adiabat implosions, the impact of jetting seeded by the support tent can also decrease the compression by 25%. We demonstrate that the inclusion of interior defects in simulations can explain the inferred compression in two fielded plastic capsule implosions and that the inclusion of voids, for which available characterization has large uncertainties, in simulations of HDC capsule implosions has a qualitatively consistent impact. This mechanism offers a potential explanation for persistently overestimated fuel compression in design simulations of layered implosions on the National Ignition Facility.
Demonstration of atmospheric plasma activated direct bonding of N-polar GaN and β-Ga2O3 (001) substrates
Authors: Jian Zhe (Ashley) , Clymore Christopher J , Sun Kai , Mishra Umesh , Ahmadi Elaheh
Published: April 2022

Direct wafer bonding of β-Ga2O3 and N-polar GaN at a low temperature was achieved by acid treatment and atmospheric plasma activation. The β-Ga2O3/GaN surfaces were atomically bonded without any loss in crystalline quality at the interface. The impact of post-annealing temperature on the quality of bonding interfaces was investigated. Post-annealing at temperatures higher than 700 °C increases the area of voids at bonded interfaces probably due to the difference in the coefficient of thermal expansion. The integration of β-Ga2O3 on the GaN substrate achieved in this work is one of the promising approaches to combine the material merits of both GaN and Ga2O3 targeting the fabrication of novel GaN/β-Ga2O3 high-frequency and high-power electronics as well as optoelectronic devices.
Highly accurate HF dimer ab initio potential energy surface
Authors: Ovsyannikov Roman I. , Makhnev Vladimir Yu. , Zobov Nikolai F. , Koput Jacek , Tennyson Jonathan , Polyansky Oleg L.
Published: April 2022

A highly accurate, (HF)2 potential energy surface (PES) is constructed based on ab initio calculations performed at the coupled-cluster single double triple level of theory with an aug-cc-pVQZ-F12 basis set at about 152 000 points. A higher correlation correction is computed at coupled-cluster single double triple quadruple level for 2000 points and is considered alongside other more minor corrections due to relativity, core-valence correlation, and Born–Oppenheimer failure. The analytical surface constructed uses 500 constants to reproduce the ab initio points with a standard deviation of 0.3 cm−1. Vibration–rotation–inversion energy levels of the HF dimer are computed for this PES by variational solution of the nuclear-motion Schrödinger equation using the program WAVR4. Calculations over an extended range of rotationally excited states show very good agreement with the experimental data. In particular, the known empirical rotational constants B for the ground vibrational states are predicted to better than about 2 MHz. B constants for excited vibrational states are reproduced several times more accurately than by previous calculations. This level of accuracy is shown to extend to higher excited inter-molecular vibrational states v and higher excited rotational quantum numbers (J, Ka).
Numerical investigation on heat transfer performance of molten salt in shell and tube heat exchangers with circularly perforated baffles
Authors: Xie Qiyue , Liang Chao , Fu Qiang , Wang Xiaoli , Liu Yu
Published: April 2022

The molten-salt heat exchanger is a critical heat transfer device used in concentrated solar power systems. In this paper, molten salt heat-transfer performance characteristics and flow resistances in shell and tube heat exchangers with perforated baffles with a notch height of 0.25D (D is the baffle diameter) are simulated. Four opening schemes that use the same opening area (10% of the baffle area) are designed. The numerical results show that the baffle holes can shrink the molten salt flow dead zone significantly and greatly decrease the flow resistance on the shell side at the cost of a slight reduction in the heat-transfer performance. The comprehensive performance of each scheme after opening is higher than that before opening, and the comprehensive performance of Scheme 4 is the best. Next, a genetic algorithm is used to optimize the Scheme 4 opening diameter. The results show that the heat-flux density on the molten-salt side reaches a maximum of 17327 W/m2 when the opening diameter is 2.24 mm. We find that the opening diameter should be maximized to optimize the comprehensive performance at a given pump power. Finally, the data are compared to other correlations. The deviation decreases gradually as the Reynolds number increases. This is because the turbulence enhancement caused by structural change is not substantial at high Reynolds numbers.
Impact of mobility degradation on endurance fatigue of FeFET with TiN/Hf0.5Zr0.5O2/SiOx/Si (MFIS) gate structure
Authors: Duan Jiahui , Xu Hao , Zhao Shujing , Tian Fengbin , Xiang Jinjuan , Han Kai , Li Tingting , Wang Xiaolei , Wang Wenwu , Ye Tianchun
Published: April 2022

This work investigates the impact of mobility degradation on endurance fatigue of a ferroelectric field-effect-transistor (FeFET) with the TiN/Hf0.5Zr0.5O2/SiOx/Si (MFIS) gate structure. We use the split capacitance–voltage (C–V) method to study the carrier mobility during the program/erase cycling. We find that significant mobility degradation occurs with increasing program/erase cycle and further deteriorates endurance characteristics. Our work provides mobility degradation as another endurance fatigue factor of FeFET besides charge trapping and trap generation, which is helpful for endurance improvement.
Numerical study of three-dimensional flapping wings hovering in ultra-low-density atmosphere
Authors: Wang Li , Tian Fang-Bao , Liu Hao
Published: April 2022

This paper presents a numerical study on the aerodynamic performance of three-dimensional flapping wings hovering in ultra-low-density fluid by using an immersed boundary method with a focus on the effects of compressibility on force production and flapping efficiency. Simulations are conducted by varying Mach number, aspect ratio, stroke amplitude, and flexibility of the wing. It is found that the lift coefficient and efficiency of rigid wings are reduced by up to 10.6% and 10.7%, respectively, when the Mach number is increased from 0.2 (weakly compressible) to 0.9 (highly compressible). To achieve sufficient lift force in the ultra-low-density atmosphere, three main strategies including varying the aspect ratio, stroke amplitude, and flexibility of wings are explored. It is found that a wing with high aspect ratio, small and fast stroke motion, and moderate flexibility is able to generate a high lift. An optimized flexible wing according to the aforementioned analysis is further proposed and simulated, which shows 38.3% and 20.8% enhancements of the mean lift coefficient and efficiency, respectively. The present study shows that the flapping aerial vehicle in ultra-low-density atmosphere is highly feasible from the aerodynamic point of view.
Surface hopping dynamics in periodic solid-state materials with a linear vibronic coupling model
Authors: Xie Hua , Xu Xiaoliang , Wang Linjun , Zhuang Wei
Published: April 2022

We report a surface hopping approach in which the implemented linear vibronic coupling Hamiltonian is constructed and the electronic wavefunction is propagated in the reciprocal space. The parameters of the linear vibronic coupling model, including onsite energies, phonon frequencies, and electron–phonon couplings, are calculated with density-functional theory and density-functional perturbation theory and interpolated in fine sampling points of the Brillouin zone with maximally localized Wannier functions. Using this approach, we studied the relaxation dynamics of the photo-excited hot carrier in a one-dimensional periodic carbon chain. The results show that the completeness of the number of Hilbert space k points and the number of phonon q points plays an important role in the hot carrier relaxation processes. By calculating the relaxation times of hot carriers under different reciprocal space sampling and extrapolating with the stretched–compressed exponential function, the relaxation times of hot electrons and holes in the quasi-continuous energy band are obtained. By considering the feedback effect in the hopping processes and analyzing the time-dependent phonon energy in different normal modes, we found that the long-wave longitudinal optical phonons play a major role in the relaxation dynamics of hot electrons and holes. We, therefore, provided herein an efficient and accurate approach for modeling the photophysical processes in periodic solid-state material systems.
Path integral molecular dynamics simulations for Green’s function in a system of identical bosons
Authors: Xiong Yunuo , Xiong Hongwei
Published: April 2022

Path integral molecular dynamics (PIMD) has been successfully applied to perform simulations of large bosonic systems in a recent study [Hirshberg et al., Proc. Natl. Acad. Sci. U. S. A. 116, 21445 (2019)]. In this work, we extend PIMD techniques to study Green’s function for bosonic systems. We demonstrate that the development of the original PIMD method enables us to calculate Green’s function and extract momentum distribution from our simulations. We also apply our method to systems of identical interacting bosons to study Berezinskii–Kosterlitz–Thouless transition around its critical temperature.
Modeling swelling effects during coffee extraction with smoothed particle hydrodynamics
Authors: Mo Chaojie , Navarini Luciano , Liverani Furio Suggi , Ellero Marco
Published: April 2022

It is commonly assumed that coffee particles swell during filtration, but it has not been clarified how different degrees of swelling affect the extraction. In this article, we propose a grain swelling model to investigate the influences of swelling on both intra-grain and inter-grain transport. The swelling is modeled through a diffusion process of excess water into the grains. The geometric expansion of the grains is connected to the local concentration of excess water through a specified deformation gradient tensor. Diffusion of soluble compounds inside the grains is coupled with the swelling dynamics through a modified diffusion equation. Inter-grain transport is modeled by solving the Navier–Stokes equation and diffusion equations. This model is solved numerically in the framework of smoothed particle hydrodynamics, and it is used to simulate the extraction of a minimal coffee bed setup and to investigate the effect of a small degree of particle swelling (<8% in size) on the extraction kinetics. It is found that under the normal operating parameter regime of espresso filtration, swelling affects the extraction mainly through the change of inter-grain transport. Swelling also alters the diffusion inside the grains, but this process has a secondary effect on the extraction. In general, swelling slightly impedes the extraction rate, but enhances the strength considerably at both fixed brewing time and fixed brewing volume. Our results justify the endeavor in the literatures to clarify the effect of possible swelling on brewing and preparation variables during coffee extraction.
Linear pair-creation damping of high-frequency plasma oscillation
Authors: Al-Naseri Haidar , Brodin Gert
Published: April 2022

We have studied the linear dispersion relation for Langmuir waves in plasmas of very high density, based on the Dirac–Heisenberg–Wigner formalism. The vacuum contribution to the physical observables leads to ultraviolet divergences, which are removed by a charge renormalization. The remaining vacuum contribution is small and is in agreement with previously derived expressions for the time-dependent vacuum polarization. The main new feature of the theory is a damping mechanism similar to Landau damping, but where the plasmon energy gives rise to creation of electron–positron pairs. The dependence of the damping rate (pair-creation rate) on the wavenumber, temperature, and density is analyzed. Finally, the analytical results of linearized theory are compared with numerical solutions.
Experimental and numerical study of the rotational Doppler shift in acoustic waves using static microphones
Authors: Liu Lianyun , Cheng Xiaojie , Zheng Xu , Qiu Yi , Hao Zhiyong
Published: April 2022

The rotational Doppler shift in acoustic waves carrying orbital angular momentum (OAM) has been applied in experiments to demonstrate the Zel'dovich amplification, which is analogously linked with the black hole radiance. However, rotating microphones used in the published experiments are difficult to assemble and intrinsically weak in the frequency response at frequencies around 0 Hz. To circumvent the limitations, this paper proposes an experimental method to study the rotational Doppler shift in acoustic OAM waves using static microphones. The Doppler shifted signals viewed by a rotating observer were extracted from the original acoustic signals at frequencies around 100 Hz, where the microphones had flat frequency response. The measured results not only demonstrated the extreme Doppler shift to a negative frequency but also showed that the acoustic amplitudes were very low when the Doppler shifted frequency was 0 Hz. This phenomenon was explained by showing in a time-domain numerical simulation that the wave was co-rotating with the observer. In addition, the characteristics of the simulated pressure contours of the rotating wave have been discussed. The proposed methods can further be used to study the physics related to the wave carrying OAM, such as the acoustic super-radiance.
Dielectrophoretic stretching of drops of silicone oil: Experiments and multi-physical modeling
Authors: Granda Rafael , Li Gen , Yurkiv Vitaliy , Mashayek Farzad , Yarin Alexander L.
Published: April 2022

It is shown experimentally that drops of two pure silicone oils of different viscosities on a polypropylene substrate do not react to the in-plane electric field. Pre-treatment of silicone oil in a humid atmosphere at 80% relative humidity enriches oil with water-related ions and results in subsequent drop slight stretching under the action of the in-plane electric field. These phenomena demonstrate that the original silicone oils do not contain a sufficient concentration of any ions and counter-ions for the appearance of any Coulomb force or Maxwell stresses, which would result in drop stretching. However, a stronger stretching of silicone oil drops on the polypropylene substrate subjected to the in-plane electric field was experimentally demonstrated when 5 wt. % of TiO2 particles was suspended in oil. The particles behave as electric dipoles and, when subjected to a nonlinear symmetric electric field, experience dielectrophoretic force, which attracts them to both electrodes in air and oil. 3D simulations of the dielectrophoretically driven evolution of silicone oil drops laden with TiO2 particles also revealed a significant drop stretching in the inter-electrode direction in qualitative agreement with the experimental data. Still, numerical simulations predict an unbounded stretching with two tongues developing at the two drop sides. This prediction disagrees with the experiments where the dielectrophoretically driven stretching ceases and steady-state drop configurations without tongues are attained. This disagreement is probably related to the fact that in the experiments, TiO2 particles settle onto the substrate and are subjected to significant additional friction forces, which could ultimately arrest them.
Two-dimensional partitioned square ice confined in graphene/graphite nanocapillaries
Authors: Zeng Zhen , Wang Tianyou , Chen Rui , Suo Mengshan , Sun Kai , Theodorakis Panagiotis E. , Che Zhizhao
Published: April 2022

As one of the most fascinating confined water/ice phenomena, two-dimensional square ice has been extensively studied and experimentally confirmed in recent years. Apart from the unidirectional homogeneous square icing patterns considered in previous studies, the multidirectional partitioned square icing patterns are discovered in this study and characterized by molecular dynamics (MD) simulations. Square icing parameters are proposed to quantitatively distinguish the partitioned patterns from the homogeneous patterns and the liquid water. The number of graphene monolayers n is varied in this study, and the results show that it is more energetically favorable to form partitioned square icing patterns when the water molecules are confined between graphite sheets (n ≥ 2) compared to graphene (n = 1). This phenomenon is insensitive to n as long as n ≥ 2 because of the short-range nature of the interaction between water molecules and the carbon substrate. Moreover, it is energetically unfavorable to form partitioned square icing patterns for a single layer of water molecules even for n ≥ 2, verifying that the interaction between layers of water molecules is another dominant factor in the formation of partitioned structures. The conversion from partitioned structure to homogeneous square patterns is investigated by changing the pressure and the temperature. Based on the comprehensive MD simulations, this study unveils the formation mechanism of the partitioned square icing patterns.
Dimerization dynamics of carboxylic acids in helium nanodroplets
Authors: Ellis Andrew M. , Davies Julia A. , Yurtsever Ersin , Calvo Florent
Published: April 2022

The dimerization of molecules in helium nanodroplets is known to preferentially yield structures of higher energy than the global energy minimum structure for a number of quite different monomers. Here, we explore dimerization in this environment using an atomistic model within statistically converged molecular dynamics (MD) trajectories, treating the solvent implicitly through the use of a thermostat, or more explicitly by embedding one monomer in a He100 cluster. The focus is on the two simplest carboxylic acids, formic and acetic, both of which have been studied experimentally. While the global minimum structure, which comprises two CO⋯HO hydrogen bonds, is predicted to be the most abundant dimer in the absence of the helium solvent, this is no longer the case once helium atoms are included. The simulations confirm the importance of kinetic trapping effects and also shed light on the occurrence of specific dynamical effects, leading to the occasional formation of high-energy structures away from minima, such as saddle configurations. Theoretically predicted infrared spectra, based on the MD statistics, are in good agreement with the experimental spectra.
Pattern selection of directionally oriented chitosan tubes
Authors: Hajdu Cintia , Kumar Pawan , Horváth Dezső , Tóth Ágota
Published: April 2022

The growth of viscoelastic curved materials, inspired by biological systems, may give rise to various complex structures. One of the simplest ways to control the pattern formation is to vary the orientation of the reaction vessel while keeping all other experimental conditions constant. Here, we report the self-organization of soft chitosan tubes by injecting acidic chitosan sol into a pool of sodium hydroxide solution, where the adhesive force between the gel and container keeps the tubules on the bottom of the reactor. The horizontal growth of the tubular structure undergoes spontaneous symmetry breaking, where instabilities develop on the surface of the chitosan tubules. Transformation of folds into wrinkles and finally to a smooth tube takes place by varying the orientation of the container. In addition to characterizing the evolving structures, we have also shown that the linear growth rate of the tube scales with the tilt angle of the container from the horizontal.
Direct data-driven forecast of local turbulent heat flux in Rayleigh–Bénard convection
Authors: Pandey Sandeep , Teutsch Philipp , Mäder Patrick , Schumacher Jörg
Published: April 2022

A combined convolutional autoencoder–recurrent neural network machine learning model is presented to directly analyze and forecast the dynamics and low-order statistics of the local convective heat flux field in a two-dimensional turbulent Rayleigh–Bénard convection flow at Prandtl number Pr=7 and Rayleigh number Ra=107. Two recurrent neural networks are applied for the temporal advancement of turbulent heat transfer data in the reduced latent data space, an echo state network, and a recurrent gated unit. Thereby, our work exploits the modular combination of three different machine learning algorithms to build a fully data-driven and reduced model for the dynamics of the turbulent heat transfer in a complex thermally driven flow. The convolutional autoencoder with 12 hidden layers is able to reduce the dimensionality of the turbulence data to about 0.2% of their original size. Our results indicate a fairly good accuracy in the first- and second-order statistics of the convective heat flux. The algorithm is also able to reproduce the intermittent plume-mixing dynamics at the upper edges of the thermal boundary layers with some deviations. The same holds for the probability density function of the local convective heat flux with differences in the far tails. Furthermore, we demonstrate the noise resilience of the framework. This suggests that the present model might be applicable as a reduced dynamical model that delivers transport fluxes and their variations to coarse grids of larger-scale computational models, such as global circulation models for atmosphere and ocean.
Static and dynamic Bethe–Salpeter equations in the T-matrix approximation
Authors: Loos Pierre-François , Romaniello Pina
Published: April 2022

While the well-established GW approximation corresponds to a resummation of the direct ring diagrams and is particularly well suited for weakly correlated systems, the T-matrix approximation does sum ladder diagrams up to infinity and is supposedly more appropriate in the presence of strong correlation. Here, we derive and implement, for the first time, the static and dynamic Bethe–Salpeter equations when one considers T-matrix quasiparticle energies and a T-matrix-based kernel. The performance of the static scheme and its perturbative dynamical correction are assessed by computing the neutral excited states of molecular systems. A comparison with more conventional schemes as well as other wave function methods is also reported. Our results suggest that the T-matrix-based formalism performs best in few-electron systems where the electron density remains low.
Surface graphitization of diamond nanotips induced by field-emission current
Authors: Kleshch Victor I. , Porshyn Vitali , Serbun Pavel , Orekhov Anton S. , Ismagilov Rinat R. , Lützenkirchen-Hecht Dirk , Obraztsov Alexander N.
Published: April 2022

Surface graphitization as a result of Joule heating by a field-emission (FE) current is revealed for needlelike diamond nanotips. The apex temperature and electrical resistance of the diamond needles during FE were measured by electron spectroscopy. Transmission electron microscopy indicated that the diamond structure in the near-surface layer was transformed into well-ordered graphene layers after FE with currents of up to 30 μA. The resulting structure can be viewed as a multi-walled carbon nanotube (MWCNT) having a diamond core. Thus, the observed FE behavior exhibited by the graphitized diamond needles is qualitatively similar to that of MWCNTs. On the other hand, due to its outstanding thermal conductivity, the diamond core ensures an efficient Joule heat dissipation, which provides better emission stability and higher currents, up to at least 225 μA. It makes these graphitized diamond needles promising candidates for high-brightness point electron sources required for various applications, e.g., in electron microscopy or scanning electron lithography.
Investigating Bénard–Marangoni migration at the air–water interface in the time domain using sum frequency generation (SFG) spectroscopy of palmitic acid monolayers
Authors: Fellows A. P. , Casford M. T. L. , Davies P. B.
Published: April 2022

Sum-frequency generation (SFG) spectroscopy is frequently used to investigate the structure of monolayer films of long-chain fatty acids at the air–water interface. Although labeled a non-invasive technique, introducing intense SFG lasers onto liquid interfaces has the potential to perturb them. In the present work, narrowband picosecond SFG is used to study the structural changes that occur in palmitic acid and per-deuterated palmitic acid monolayers at the air–water interface in response to the high field strengths inherent to SFG spectroscopy. In order to determine structural changes and identify measurement artifacts, the changes in specific resonance intensities were measured in real-time and over a broad range of surface concentrations from films spread onto a stationary Langmuir trough. Using narrowband instead of broadband SFG minimizes the overlap of the incident infrared beam in the lipid C–H stretching region with resonances from the water sub-phase. Nevertheless, narrowband SFG still generates a thermal gradient at the surface, which produces a significant decrease in local concentration in the area of the laser spot caused by Bérnard–Marangoni convection originating in the sub-phase. The decrease in concentration results in an increase in the conformational disorder and a decrease in the tilt angle of lipid tails. Crucially, it is shown that, even at the highest monolayer concentrations, this gives rise to a measurement effect, which manifests itself as a dependence on the spectral acquisition time. This effect should be taken into account when interpreting the structure of monolayer films on liquid surfaces deduced from their SFG spectra.
Cold-modulated leaf compounds in winter triticale DH lines tolerant to freezing and
Authors: Gołębiowska Gabriela , Stawoska Iwona , Wesełucha-Birczyńska Aleksandra
Published: April 2022

Tolerance to freezing and seedling diseases caused by Microdochium spp. is an essential trait for the wintering of triticale (×Triticosecale Wittmack) and other cereals. Preceding multi-year studies indicate that after long-term exposure to the low temperature, cereal seedlings acquire a genotype-dependent cross-tolerance to other subsequent stresses. This paper presents the first non-gel protein profiling performed via high performance liquid chromatography coupled with Mass Spectrometry as well as Fourier Transform-Raman spectroscopy measurements performed directly on leaves of triticale seedlings growing under different conditions. The research used doubled haploid lines selected from the mapping population, with extreme tolerance/susceptibility to freezing and M. nivale infection. These non-targeted methods led to the detection of twenty two proteins cold-accumulated in the most tolerant seedlings in relation to susceptible ones, classified as involved in protein biosynthesis, response to different stimuli, energy balancing, oxidative stress response, protein modification, membrane structure and anthocyanin synthesis. Additionally, in seedlings of the most freezing- and M. nivale-tolerant line, cold-hardening caused decrease of the carotenoid and chlorophyll content. Moreover, a decrease in the band intensity typical for carbohydrates as well as an increase in the band intensity characteristic for protein compounds were detected. Both studied lines revealed a different answer to stress in the characteristics of phenolic components.
A screen of repurposed drugs identifies AMHR2/MISR2 agonists as potential contraceptives
Authors: Li Yi , Wei Lina , Meinsohn Marie-Charlotte , Suliman Rana , Chauvin Maeva , Berstler Jim , Hartland Kate , Jensen Mark M. , Sicher Natalie A. , Nagykery Nicholas , Donahoe Patricia K. , Pepin David
Published: April 2022

Significance

This study aims to identify drugs that activate the Mullerian inhibiting substance pathway to be used for contraception or other applications in women’s health. We describe a high-throughput screening pipeline to identify small molecules that activate the Mullerian inhibiting substance type 2 receptor (MISR2) and validate their activity in bioassays. We identify five compounds from a repurposed drug library that specifically induce MISR2 signaling, trigger regression of the Mullerian duct, and inhibit follicle activation. We test these compounds in vivo and show that they can repress folliculogenesis in mice and rats in an
Misr2
-dependent manner. These drugs may represent a class of ovarian regulators that inhibit preantral follicle activation and growth.
Metal–nitrogen–carbon-based nanozymes: advances and perspectives
Authors: Wang Ying , Huang Rui , Han Jeong Woo
Published: April 2022

Natural enzymes are widely employed as powerful biocatalysts. However, their further application is limited by the intrinsic characteristics of enzymes. To overcome this drawback, nanomaterials with enzyme-mimicking performance (defined as nanozymes) have attracted tremendous attention in recent decades. To date, over 50 kinds of nanomaterials have been found to possess inherent enzyme-mimetic properties. Among these, metal–nitrogen–carbon (M-N-C) nanozymes are the most promising nanomaterials due to their satisfactory activity, tunable configuration and chemical stability. Consequently, it is of great research value to focus on progress in this field. In this review, we systematically summarize recent advances in M-N-C nanozymes with various enzyme-like properties, including peroxidase-like, oxidase-like, catalase-like, superoxide dismutase-like and multiple enzyme-like performances. Furthermore, strategies for regulating enzyme-like activity and substrate specificity are comprehensively highlighted at the atomic level. The introduction of heteroatoms, rational design of the coordination environment and engineering of M-N-C nanostructures are discussed by combining experimental investigations with theoretical explorations. These approaches can unveil the origins of and provide insights into the enzyme-like mechanisms. We also review recent progress with M-N-C nanozymes for sensing and biomedical applications. Finally, current challenges and future opportunities for the development of advantageous M-N-C nanozymes are also proposed. This review is expected to provide inspiration and guidelines for further research on the rational design of perfect nanozymes.
Review on magnonics with engineered spin textures
Authors: Petti Daniela , Tacchi Silvia , Albisetti Edoardo
Published: April 2022

Spin textures, such as non-uniform domain arrangements, domain walls and skyrmions are naturally occurring structures in magnetic materials. Recently, the unique properties of spin textures such as their reconfigurability, stability and scalability towards nanoscale dimensions, has sparkled the interests towards their use as active elements in spintronic devices. In the framework of magnonics, which aims to use spin waves (SWs) for carrying and processing information, using spin textures allows to harness an extremely rich phenomenology for designing new functionalities. In this review, we focus on the recent developments on the control and stabilization of engineered spin textures, and their applications in the field of magnonics. First, we introduce the main techniques used for stabilizing the spin textures and controlling their properties. Then we review the recent results on the use of engineered spin textures for guiding, emitting and manipulating SWs, and the recent proposals on the realization of complex functionalities using integrated spin-texture-based systems, which hint to possible future directions for technological prospects.