bluuebunny/crossref_metadata_2025 huggingface dataset:
Der Nationale Kompetenzbasierte Lernzielkatalog 2.0 für das
Fach „Physikalische und Rehabilitative Medizin,
Naturheilverfahren“. Konsentierte Ergebnisse beteiligter
Fachgesellschaften der AWMF.
Authors: Mau Wilfried , Bethge Matthias , Liebl Max Emanuel
Published: August 2023

Hintergrund Im Rahmen der Weiterentwicklung des Nationalen
Kompetenzbasierten Lernzielkatalogs (NKLM) zur Version 2.0 erfolgte auch eine
Überarbeitung der Lernziele im bisherigen Querschnittsfach
„Rehabilitation, Physikalische Medizin, Naturheilverfahren“. Da
der NKLM grundsätzlich fächerübergreifend angelegt ist,
von verschiedenen Seiten aber eine Fächerzuordnung notwendig schien,
initiierten die Arbeitsgemeinschaft wissenschaftlich-medizinischer
Fachgesellschaften (AWMF) und der Medizinische Fakultätentag einen
Fächerzuordnungsprozess. Der Zuordnungsprozess für das Fach
„Physikalische und Rehabilitative Medizin, Naturheilverfahren“
(PRM-NHV; laut Fächerliste des ersten Referentenentwurfes der geplanten
Approbationsordnung aus dem Jahr 2020) wird in dieser Arbeit dargestellt.

Materialien und Methoden Die AWMF lud ihre Mitgliedsgesellschaften ein,
sich an der Zuordnung von Lernzielen der Kapitel VI, VII und VIII des NKLM 2.0
zu den einzelnen Fächern zu beteiligen, zu denen sie nach eigener
Einschätzung einen Beitrag in der Lehre leisten. Für
„PRM-NHV“ beteiligten sich Vertreter*innen der DGRW,
DGPRM, DGOU sowie der DGNHK. In einem strukturierten Konsensprozess nach der
DELPHI-Methodik erfolgten Auswahl und Konsentierung der Lernziele.
Anschließend erfolgte durch die AWMF eine Fächerempfehlung.

Ergebnisse Aus dem NKLM 2.0 wurden insgesamt 100 kompetenzbasierte
Lernziele der Kapitel VII und VIII für das Fach
„PRM-NHV“ von den Vertreter*innen der beteiligten
Fachgesellschaften zur Darstellung auf der NKLM 2.0-Online-Plattform
konsentiert.

Schlussfolgerungen Im Rahmen des grundlegend geplanten Reformprozesses des
Medizinstudiums und unter dem Dach der AWMF und des Medizinischen
Fakultätentags gelang die breite Konsentierung von Lernzielen des NKLM
2.0 für die kompetenzbasierte Lehre im Fach „PRM-NHV“
durch die beteiligten Fachgesellschaften. Damit wird eine für alle
medizinischen Fakultäten wichtige Orientierung sowohl für die
Weiterentwicklung der Lehre im Querschnittsbereich „Rehabilitation,
Physikalische Medizin, Naturheilverfahren“ gemäß der
seit zwanzig Jahren gültigen 9. Revision der ÄApprO als auch
für die Vorbereitung der entsprechenden Fächer im
Referentenentwurf der neuen ÄApprO gegeben.
Pd-Catalyzed Remote δ-C(sp2)–H Functionalization in Phenylalaninol: Expanding the Library of Phenylalaninols
Authors: Babu Srinivasarao Arulananda , Singh Prabhakar
Published: August 2023

We report the Pd(II)-catalyzed, picolinamide-directed δ-C(sp2)–H (ortho) functionalization of phenylalaninol scaffolds. Assembling of (ortho) δ-C–H arylated, alkylated, benzylated, alkenylated, brominated, and iodinated phenylalaninol scaffolds was accomplished. The δ-C(sp2)–H arylation reaction of phenylalaninol occurred under neat conditions. Hydrolysis of the picolinamide moiety and synthetic utility of the δ-C(sp2)–H arylated substrates were explored. We have also shown the preparation of some modified Matijin–Su (aurantiamide) derivatives using the bis δ-C–H (ortho) arylated phenylalaninol compounds obtained from the δ-C(sp2)–H arylation reaction (Matijin–Su is an anti-HBV agent possessing the phenylalaninol unit). Considering the importance of phenylalaninols, this work contributes to expanding the phenylalaninol library and demonstrates the substrate scope development in remote δ-C(sp2)–H functionalization reactions.
The Reconstructive Toolbox
Authors: Hallock Geoffrey G.
Published: August 2023

Historically, the approach to any reconstructive challenge, whether intentionally or intuitively, can be seen to follow distinct guidelines that could aptly be called “reconstructive metaphors.” These have been intended to inform us as to the “what, “when” and “where” this attempt can best be achieved. Yet the “how” or means to accomplish this goal, usually also intuitively well understood, in a similar vein can now be expressed to be within our “reconstructive toolbox.” The latter will distinctly mirror our individuality and contain not only the various hardware that we deem essential, but also the means to access whatever technology we may be comfortable with. No toolbox, even if overflowing will ever be full, as potential options and the diversity they represent surely approaches infinity. But the truly excellent reconstructive surgeon will know when their toolbox is in any way lacking, and fears not remedying that deficiency even if the talents of another colleague must be sought, so as always to ensure that the patient will obtain the best appropriate treatment!
The Influence of Corticosteroid Injections on Postoperative Outcomes of Carpal Tunnel Release: A Systematic Review
Authors: Kumaş Ali , Warenburg Milly van de , Natroshvili Tinatin , Kemler Marius , Foumani Mahyar
Published: August 2023

Background Carpal tunnel syndrome can be treated with corticosteroid injections (CIs) and surgery. In this systematic review, the influence of previous CI on different postoperative outcomes after carpal tunnel release is evaluated.

Methods A systematic literature search using several databases was performed to include studies that examined patients diagnosed with carpal tunnel syndrome who received preoperative or intraoperative CIs.

Results Of 2,459 articles, 9 were eligible for inclusion. Four papers reported outcomes of preoperative and four outcomes of intraoperative CIs. One study evaluated patients who received both intraoperative and preoperative corticosteroids.

Conclusion Intraoperative CIs are associated with reduced postoperative pain after carpal tunnel release and support earlier recovery of the hand function that can be objectified in a faster median nerve conduction speed recovery and lower Boston Carpal Tunnel Questionnaire (BCTQ) scores. Using preoperative CIs did not lead to enhanced recovery after carpal tunnel release, and both preoperative and intraoperative CIs might be predisposing factors for infections.
Hyaluronic Acid Filler Injection Guided by Doppler Ultrasound
Authors: Lee Won
Published: August 2023

Doppler ultrasound can be used to detect almost all arteries of the face before injecting the hyaluronic acid (HA) filler. The relatively more dangerous sites of filler injection are the glabellar wrinkle, forehead, temple, nose, and nasolabial fold area, and it is recommended to map the vasculature of these areas by Doppler ultrasound before performing filler injection. The Doppler ultrasound detection method is included as a video. Internal carotid arterial branches, the supratrochlear, supraorbital, and dorsal nasal arteries, and external carotid arterial branches, the superficial temporal and facial arteries, are very important arteries when injecting HA filler; thus, Doppler ultrasound detection is recommended.
Polarization of THP-1-Derived Macrophage by Magnesium and MAGT1 Inhibition in Wound Healing
Authors: Oh Mun Ho , Jang JaeHyuk , Lee Jong Hun
Published: August 2023

Background Macrophages play a major role in wound healing and prevent infection from the outside. Polarization conversion of macrophages regulates aspects of inflammation, and two macrophages, M1 (classically activated) and M2 (alternatively activated), exist at both ends of broad-spectrum macrophage polarization. Thus, we aimed to investigate whether macrophage polarization can be artificially regulated. To this end, MgSO4 and small-interfering RNA (siRNA) targeting magnesium transport 1 (MAGT1) were used to investigate the effects of intracellular magnesium (Mg2+) concentrations on the differentiation of macrophages in vitro.

Methods THP-1 derived macrophages maintained in a culture medium containing 5 mM MgSO4 and siRNA to inhibit the expression of MAGT1. As comparative groups, THP-1 derived macrophages polarized into M1 and M2 macrophages by treatment with M1, M2 inducer cytokine. The polarization status of each group of cells was confirmed by cell surface antigen expression and cytokine secretion.

Results We found that MgSO4 treatment increased CD163 and CD206, similar to the effect noted in the M2 group. The expression of CD80 and HLA-DR was increased in the group treated with MAGT1 siRNA, similar to the effect noted in the M1 group. Functional assays demonstrated that the group treated with MgSO4 secreted higher levels of IL-10, whereas the MAGT1 siRNA-treated group secreted higher levels of IL-6 cytokines. Additionally, the conditional medium of the Mg2+ treated group showed enhanced migration of keratinocytes and fibroblasts.

Conclusion Mg2+ can help to end the delay in wound healing caused by persistent inflammation in the early stages.
Review of Percutaneous Transesophageal Gastrostomy: A Multi-Hospital Academic Institution's Case Series of 24 Patients
Authors: Frenkel Joseph , Krausz Steven , Cynamon Jacob , Golowa Yosef , Hirschl David
Published: August 2023

Percutaneous transesophageal gastrostomy (PTEG) is a minimally invasive technique involving percutaneous placement of an enteral tube via an esophagostomy in patients for whom conventional gastrostomy is contraindicated. We present a series of 24 patients who received PTEG, discuss indications for the procedure, and review outcomes. A retrospective chart review of the EMR was performed for patients who received PTEG from March 2016 through October 2021. Twenty-four patients were identified, and their records were reviewed for placement indication, technical success, adverse events, feeding complications, and replacement. Twenty-four patients (aged 29–91) required gastric tube placement for either enteral feeding or palliative venting. Conventional gastrostomy was contraindicated for reasons including difficult anatomy (eight), gastric surgery (five), malignancy (four), ascites (four), and wounds/infections (three). Technical success rate for placement was 100%. Minor postprocedural complications included local cellulitis, significant tube clogging, and dislodgement. There was one major complication, a significant bleed through the catheter entry site, which was successfully treated with a carotid covered stent. PTEG is safe and effective and should be strongly considered for gastric drainage or provisional supplemental nutrition in patients for whom percutaneous gastrostomy is contraindicated or technically not feasible.
Theoretical examination of QED Hamiltonian in relativistic molecular orbital theory
Authors: Inoue Nobuki , Watanabe Yoshihiro , Nakano Haruyuki
Published: August 2023

Theoretical discussions are given on issues in relativistic molecular orbital theory to which the quantum electrodynamics (QED) Hamiltonian is applied. First, several QED Hamiltonians previously proposed are sifted by the orbital rotation invariance, the charge conjugation and time reversal invariance, and the nonrelativistic limit. The discussion on orbital rotation invariance shows that orbitals giving a stationary point of total energy should be adopted for QED Hamiltonians that are not orbital rotation invariant. A new total energy expression is then proposed, in which a counter term corresponding to the energy of the polarized vacuum is subtracted from the total energy. This expression prevents the possibility of total energy divergence due to electron correlations, stemming from the fact that the QED Hamiltonian does not conserve the number of particles. Finally, based on the Hamiltonian and energy expression, the Dirac–Hartree–Fock (DHF) and electron correlation methods are reintroduced. The QED-based DHF equation is shown to give information on positrons from negative-energy orbitals while having the same form as the conventional DHF equation. Three electron correlation methods are derived: the QED-based configuration interactions and single- and multireference perturbation methods. Numerical calculations show that the total energy of the QED Hamiltonian indeed diverged and that the counter term is effective in avoiding the divergence. The relativistic molecular orbital theory presented in this article also provides a methodology for dealing with systems containing positrons based on the QED Hamiltonian.
Mechanical characteristics and fracture mechanisms of fissured rock mass samples with various opening sizes
Authors: Zeng Jiajun , Wang Qiyun , Shen Qingqing , Zeng Qiang , Pang Zhaohui
Published: August 2023

To obtain the effect of fracture failure mechanics characteristics and behavior of brittle rock masses on the compound factors of fissure openings and inclination, uniaxial loading tests were performed on single-fissured rock-mass specimens with different openings using a rock mechanics test machine. The test results show that with the increase in fissure openings, the fissured rock-mass peak strength variation behavior with the increase in fissure inclination angle changes from first decreasing and then increasing to gradually increasing, and the angle at the minimum value of peak strength shifts from 45° to 0°. At the same fissure angle, the peak strength of the fissured rock mass decreases with the increase in the fissure opening size. The greater the opening size of the prefabricated fissure, the smaller the peak strength of the fissured rock mass and the greater the influence of changes in the fissure inclination angle. The elastic modulus of the fissured rock-mass specimen shows a positive correlation with the fissure inclination angle and a negative correlation with the fissure opening size. Combined with the neighborhood stress field analysis of the open fissure tip, the criterion of composite fracture under tension failure is established, and the linear relationship between the stress intensity factors KI and KII is verified. The criterion of composite fracture of open fissures under shear failure is also identified, which is based on the linear relationship between the stress intensity factors.
A specialized partial discretized optimization algorithm for SLL suppression in FSS design
Authors: Pei Y. , Qin J. J. , Yu A. R. , Yi R. C. , Yu X. X. , Liu S. B. , Zhu C. Q. , Zhu G. R. , Hou X. Y.
Published: August 2023

Side Lobe Level (SLL) suppression is a challenging but essential part of frequency selective surface (FSS) structural design. The SLL of the radiation pattern is a key parameter demonstrating the directional anti-interference ability and mainly depends on the geometry of the FSS. However, the correlation between SLL and FSS structural parameters is extremely complicated. A minor FSS structure change may result in a drastic diversion in the sidelobe’s direction or level, making the SLL the most difficult parameter to optimize. In this paper, an efficient optimization method specifically for SLL suppression is proposed. We discretized the edges of split square ring FSS structures by binary representation and generated new patterns based on the genetic algorithm. Optimization results showed that in the most optimal structure, the SLL was −23.41 dB, exhibiting a 5.17 dB reduction. Meanwhile, the center frequency variation was less than 2%. Moreover, the computation time cost was reduced by over 90% compared with that of the fully discretized pattern optimization method, showing that this novel method was truly effective in getting SLL suppressed FSS structures.
Correlation between impulse magnitude and inhibition of cell proliferation in alternating electric fields therapy
Authors: Oh Geon , Jo Yunhui , Gi Yongha , Hong Jinyoung , Kim Jonghyun , Lee Boram , Yoon Myonggeun
Published: August 2023

This study was designed to investigate the correlation between the impulse by dielectrophoretic force applied inside a dividing cell during alternating electric fields therapy and the inhibition of cell proliferation. Distributions of the electric field and dielectrophoretic force inside a dividing cell were calculated using the finite element method of COMSOL Multiphysics. Based on the results, the average magnitude of the impulse by the dielectrophoretic force applied to the cleavage furrow inside a dividing cell placed in various directions was calculated as a function of electric field intensity at an extracellular reference point. The simulation results showed that the average magnitude of the impulse to the cleavage furrow inside a dividing cell ranged from 1.51 × 10−9 to 1.49 × 10−7 N s when tumor treating fields with an intensity ranging from 0.1 to 1 V/cm is applied at an extracellular reference point for 6 h. To verify the relationships between the impulse by the dielectrophoretic force and the inhibition of cell proliferation, the survival fractions of the four cancer cell lines were determined as a function of intensity and time duration of the electric field. The correlation between the magnitude and application time of the electric field and the survival fractions of the four cell lines showed similar trends in vitro. These results suggest that both the dielectrophoretic force and the time required for the force to act are proportionally related to the inhibitory effect on dividing cells, enabling this impulse to be used as a reference to quantify the inhibition of cell proliferation.
Enhancement and localization of atomistic polarity and polarizability memory in light scattering upon hydrogenation of luminescent spherical 1 nm Si nanoparticles
Authors: Mantey Kevin , Rao Satish , Nayfeh Ammar , Palleschi Simonetta , Elhalawany Noha , Abuhassan Laila , Aldwayyan Abdullah S. , Alsalhi Mohamad , Nayfeh Munir H.
Published: August 2023

The classical light interactions of nanosilicon, which is a dielectric material, are exceedingly weak for radius r ≪ λ (wavelength), scaling as r6. It exhibits geometrical anisotropy-based depolarization, which is the basis for the very weak response in isotropic structures (nanosphere). Recently, surface enhanced Raman scattering (SERS) in DNA decorated with ultrasmall Si nanoparticles has been demonstrated, affording an effective alternative to plasmon–metal particles. In this paper, we execute fundamental quantum atomistic computation of 1 nm hydrogenated Si particles, with different surface reconstruction and termination, including Si–H, H–Si–Si–H (dimer molecules), or oxygenated dimer bridges (H–Si–O–Si–H). We obtain the mechanical vibrational modes of the particles. Our results show that by changing the surface configuration one can control the symmetry and normal vibration modes, and enhance the polarizability, polarity, and light interactions (scattering, absorption, and depolarization/memory). The low frequency polarizability (Raman scattering) shifts spatially from the interior to the surface, while the infrared polarity remains on the surface, but its bandwidth narrows spectrally. The results support previous infrared absorption and light scattering and depolarization measurements, as well recent SERS, which enable Si nanoparticles to be an effective alternative to plasmonic metal particles. Molecular surface reconstruction in terms of Si dimers and bridges were suggested as the source of the novel nonlinear and anisotropic luminescence and photonic properties of Si nanoparticles. Such control affords potential for optimizing the design and operation of a wide range of opto-electronic advanced scattering and luminescence devices.
Intrinsic multiferroicity and magnetoelectric coupling in VSI2 monolayer
Authors: Li Dong , Liu Pengyu , He Ruiman , Bai Yihang , Liu Chang , Wang Bing , Jia Guanwei
Published: August 2023

Two dimensional (2D) multiferroic materials have great potential for miniaturized electronic and high-density multi-states data storage devices due to the coexistence of electric and spin polarization. Because the origins of magnetism and ferroelectricity are mutually exclusive and difficult to coexist, there are still rare to date 2D multiferroic semiconductors with good performance. Here, we propose a 2D multiferroic material, VSI2 monolayer, which has both ferromagnetic and ferroelectric properties by first principles calculation. It shows robust ferroelectricity with an appropriate switching barrier (∼140 meV), and the in-plane ferroelectric polarization is 1.44 × 10−10 C/m. At the same time, the VSI2 monolayer magnetic easy axis is along the b-axis direction and owns a large magnetic anisotropy energy (MAE) (512 μeV/V-ion). Based on Monte Carlo simulations of the Heisenberg model, the Curie temperature (TC) is calculated to be approximately 92 K. In addition, biaxial strain can significantly change the MAE, and the in-plane magnetic easy axis can be switched to the out-of-plane direction by 5% biaxial tensile strain. In particular, we can change the magnetic moment at the two ends of VSI2 nanoribbons by switching the direction of electric polarization, providing an opportunity for the application of magnetic-electric control and memory devices. Our theoretical prediction provides a good platform for studying the 2D multiferroic effects and spintronic properties.
Bridging semiempirical and ab initio QM/MM potentials by Gaussian process regression and its sparse variants for free energy simulation
Authors: Snyder Ryan , Kim Bryant , Pan Xiaoliang , Shao Yihan , Pu Jingzhi
Published: August 2023

Free energy simulations that employ combined quantum mechanical and molecular mechanical (QM/MM) potentials at ab initio QM (AI) levels are computationally highly demanding. Here, we present a machine-learning-facilitated approach for obtaining AI/MM-quality free energy profiles at the cost of efficient semiempirical QM/MM (SE/MM) methods. Specifically, we use Gaussian process regression (GPR) to learn the potential energy corrections needed for an SE/MM level to match an AI/MM target along the minimum free energy path (MFEP). Force modification using gradients of the GPR potential allows us to improve configurational sampling and update the MFEP. To adaptively train our model, we further employ the sparse variational GP (SVGP) and streaming sparse GPR (SSGPR) methods, which efficiently incorporate previous sample information without significantly increasing the training data size. We applied the QM-(SS)GPR/MM method to the solution-phase SN2 Menshutkin reaction, NH3+CH3Cl→CH3NH3++Cl−, using AM1/MM and B3LYP/6-31+G(d,p)/MM as the base and target levels, respectively. For 4000 configurations sampled along the MFEP, the iteratively optimized AM1-SSGPR-4/MM model reduces the energy error in AM1/MM from 18.2 to 4.4 kcal/mol. Although not explicitly fitting forces, our method also reduces the key internal force errors from 25.5 to 11.1 kcal/mol/Å and from 30.2 to 10.3 kcal/mol/Å for the N–C and C–Cl bonds, respectively. Compared to the uncorrected simulations, the AM1-SSGPR-4/MM method lowers the predicted free energy barrier from 28.7 to 11.7 kcal/mol and decreases the reaction free energy from −12.4 to −41.9 kcal/mol, bringing these results into closer agreement with their AI/MM and experimental benchmarks.
A deep reinforcement learning based research for optimal offloading decision
Authors: Ren Jianji , Yang Donghao , Yuan Yongliang , Wei Huihui , Wang Zhenxi
Published: August 2023

Currently, a concern about power resource constraints in the distribution environment is being voiced increasingly, where the increase of power consumption devices overwhelms the terminal load unaffordable and the quality of power consumption cannot be guaranteed. How to acquire the optimal offloading decision of power resources has become a problem that needs to be addressed urgently. To tackle this challenge, a novel reinforcement learning algorithm named Deep Q Network with a partial offloading strategy (DQNP) is proposed to optimize power resource allocation for high computational demands. In the DQNP, a coupled coordination degree model and Lyapunov algorithm are introduced, which trade-offs and decouples the relationships between local-edge and latency–energy consumption. To derive the optimal offloading decision, the resource computation utility function is selected as the objective function. In addition, model pruning is availed to further improve the training time and inference results. Results show that the proposed offloading mechanism can significantly decrease the function value and decline the weighted sum of latency and energy consumption by an average of 3.61%–7.31% relative to other state-of-the-art algorithms. Additionally, the energy loss in the power distribution process is successfully mitigated; furthermore, the effectiveness of the proposed algorithm is also verified.
Exchange correlation potentials from full configuration interaction in a Slater orbital basis
Authors: Tribedi Soumi , Dang Duy-Khoi , Kanungo Bikash , Gavini Vikram , Zimmerman Paul M.
Published: August 2023

Ryabinkin–Kohut–Staroverov (RKS) theory builds a bridge between wave function theory and density functional theory by using quantities from the former to produce accurate exchange-correlation potentials needed by the latter. In this work, the RKS method is developed and tested alongside Slater atomic orbital basis functions for the first time. To evaluate this approach, full configuration interaction computations in the Slater orbital basis are employed to give quality input to RKS, allowing full correlation to be present along with correct nuclei cusps and asymptotic decay of the wavefunction. SlaterRKS is shown to be an efficient algorithm to arrive at exchange-correlation potentials without unphysical artifacts in moderately-sized basis sets. Furthermore, enforcement of the nuclear cusp conditions will be shown to be vital for the success of the Slater-basis RKS method. Examples of weakly and strongly correlated molecular systems will demonstrate the main features of SlaterRKS.
Maximum propagation speed and Cherenkov effect in optical phonon transport through periodic molecular chains
Authors: Burin Alexander L. , Parshin Igor V. , Rubtsov Igor V.
Published: August 2023

Optical phonons serve as the fast and efficient carriers of energy across periodic polymers due to their delocalization, large group velocity because of covalent bonding, and large energy quantum compared to that for acoustic phonons as it was observed in a number of recent measurements in different oligomers. However, this transport is dramatically sensitive to anharmonic interactions, including the unavoidable interaction with acoustic phonons responsible for transport decoherence, suppressing ballistic transport at long distances. Here, we show that this decoherence is substantially suppressed if the group velocity of optical phonons is less than the sound velocity of acoustic phonons; otherwise, ballistic transport is substantially suppressed by a Cherenkov-like emission of acoustic phonons. This conclusion is justified considering energy and momentum conservation during phonon absorption or emission and supported by the numerical evaluation of the lifetimes of the optical phonons. It is also consistent with the recent experimental investigations of ballistic optical phonon transport in oligomers with the minor exception of relatively short oligophenylenes.
A narrow-linewidth high-power fused silica Brillouin laser
Authors: Jin Duo , Bai Zhenxu , Chen Yifu , Fan Wenqiang , Ke Jun , Wang Yulei , Lü Zhiwei , Mildren Richard P.
Published: August 2023

Free-space Brillouin lasers (BLs) generate high-power narrow-linewidth laser outputs at specific wavelengths. However, despite these impressive results, further compressing the Stokes linewidth while maintaining a high-power output remains a challenge. This study was conducted to investigate the design of BLs, starting from the phase-matching conditions and stability of a Brillouin cavity, for media with different phonon frequencies. A high-power and narrow-linewidth output can be realized using large-size, wide-gain-bandwidth Brillouin media. We experimentally demonstrated a BL using fused silica and diamond with the same cavity parameters. Stokes powers of 21.6 and 18.9 W were obtained with fused silica and diamond, respectively, at an available pump power of 58 W. Using fused silica, a Stokes linewidth of 1.2 kHz was obtained, which is two times narrower than that obtained using the diamond BL. Such BL design routes for various Brillouin media provide a path for achieving high-power, ultra-narrow-linewidth laser radiation at specific wavelengths.
Induced charge electro-osmotic mixing performance of viscoelastic fluids in microchannels with an electrically conductive plate
Authors: Wei Yuqi , Chen Yi , Xu Jun , Li Jie
Published: August 2023

Micromixers have important applications in lab-on-a-chip, biomanufacturing, and chemical engineering. In this study, a micromixer with a conductive barrier plate based on the induced charge electro-osmosis is proposed. The Oldroyd-B constitutive model was chosen to characterize the flow characteristics of viscoelastic fluids, and the Poisson–Boltzmann model was used to characterize the electrokinetic properties. The effects of the installation of the conductive plate, the concentration of the polymer, and the shape of the conductive plate on the mixing were studied based on the finite volume method. The mixing efficiency of the viscoelastic fluids is 78.3% when a non-conductive plate is placed in the micromixer. However, placing a conductive plate increases the mixing efficiency to 89.8%. As the polymer concentration increases, the mixing efficiency increases, which is attributed to the elastic instability. As the curvature of the conductive plate increases from 0° to 360°, the mixing efficiency of the Newtonian fluid increases by 2.82%, while that of the polyacrylamide solutions at concentrations of 100 and 250 ppm increases by 5.31% and 1.97%, respectively.
Melting curves of ice polymorphs in the vicinity of the liquid–liquid critical point
Authors: Piaggi Pablo M. , Gartner Thomas E. , Car Roberto , Debenedetti Pablo G.
Published: August 2023

The possible existence of a liquid–liquid critical point in deeply supercooled water has been a subject of debate due to the challenges associated with providing definitive experimental evidence. The pioneering work by Mishima and Stanley [Nature 392, 164–168 (1998)] sought to shed light on this problem by studying the melting curves of different ice polymorphs and their metastable continuation in the vicinity of the expected liquid–liquid transition and its associated critical point. Based on the continuous or discontinuous changes in the slope of the melting curves, Mishima [Phys. Rev. Lett. 85, 334 (2000)] suggested that the liquid–liquid critical point lies between the melting curves of ice III and ice V. We explore this conjecture using molecular dynamics simulations with a machine learning model based on ab initio quantum-mechanical calculations. We study the melting curves of ices III, IV, V, VI, and XIII and find that all of them are supercritical and do not intersect the liquid–liquid transition locus. We also find a pronounced, yet continuous, change in the slope of the melting lines upon crossing of the liquid locus of maximum compressibility. Finally, we analyze the literature in light of our findings and conclude that the scenario in which the melting curves are supercritical is favored by the most recent computational and experimental evidence. Although the preponderance of evidence is consistent with the existence of a second critical point in water, the behavior of ice polymorph melting lines does not provide strong evidence in support of this viewpoint, according to our calculations.
Simple lattice model explains equilibrium separation phenomena in glassy polymers
Authors: Yuan Tianmu , De Angelis Maria Grazia , Sarkisov Lev
Published: August 2023

The Robeson bound is a theoretical limit that applies to kinetics-driven membrane separations of gas mixtures. However, this bound does not apply to sorption-driven membrane processes such as CO2/N2 separation, which lacks a theoretical explanation. As a result, we are uncertain about the factors that control the limiting behavior of sorption-driven separations. To address this issue, we employed a simple lattice model and dynamic mean field theory to examine the transport properties of disordered model structures, isolating sorption effects from purely kinetic effects. Our findings indicate that transport effects play a crucial role in sorption-driven processes, and perm-selectivity is consistently lower than sorption selectivity, which is an unattainable limit. We used basic geometric fragments of the structure to explain how transport effects emerge and manifest themselves in sorption-driven processes.
Coupled bubble dynamics and interaction mechanisms of adjacently nucleated vapor bubbles under subcooled pool boiling regime
Authors: Kumar Alok , Kangude Prasad , Srivastava Atul
Published: August 2023

The present work investigates the plausible modes of interaction between two adjacently located vapor bubbles growing on high wettability surface during subcooled nucleate pool boiling. The study becomes important as the phenomenon of bubble interaction has a significant impact on the resulting bubble dynamic parameters as well as on microlayer dynamics of the respective vapor bubbles. As against the symmetric growth of microlayer in the case of isolated pool boiling, microlayers of mutually interacting vapor bubbles no longer remain symmetric and tend to deplete relatively faster, thereby influencing the resulting wall heat transfer rates. Toward this, the microlayers and dynamics of adjacently located interacting vapor bubbles have been mapped in a simultaneous manner using thin-film interferometry and high-speed rainbow schlieren deflectometry as a function of varying subcooling levels. Results of the experiments revealed that parameters such as non-dimensional spacing between the two vapor bubbles, supplied heat flux, and degree of subcooling have a strong impact on the mechanism of bubbles' interaction, which, in turn, influence the bubble departure frequency, bubble diameter, and microlayer dynamics. Three dominant modes of bubble interaction, hydrodynamic interaction (HI), thermal interaction (TI), and coalescence (C), were identified as a function of the level of subcooling. Quantification of the experimental data showed that the equivalent diameter of the vapor bubble increases with an increase in the level of heat flux, while it decreases with an increase in the subcooling level. Additionally, the secondary nucleation affects the liftoff time and movement of the primary bubble and can hydrodynamically deplete the microlayer of the first bubble even when the bubbles are far apart, with the depletion rates showing a strong dependence on the growth rate and location of the secondary nucleation.
Synthesis of AlN single crystal by solution growth method using type 430 ferritic stainless steel flux
Authors: Li Sen , Adachi Masayoshi , Ohtsuka Makoto , Fukuyama Hiroyuki
Published: August 2023

We propose a new AlN crystal growth method using Fe-based fluxes. AlN single crystals with a thickness of 67–212 µm were epitaxially grown on an AlN bulk substrate by a solution growth method using type 430 ferritic stainless steel flux. The full width at half maximum values of the x-ray rocking curves of (0002) and (10–12) of the synthesized AlN were 137 and 83 arcsec, respectively. The impurity concentrations of carbon were significantly decreased from 3 × 1019 atoms/cm3 in seed crystal to 6 × 1017 atoms/cm3 in synthesized crystal. The features of the method developed in this study are described as follows: (1) steel-based alloys are used as a flux, which are readily available and low-cost; (2) the growth temperature is 1700 °C, which is much lower than that of the sublimation method; (3) no high-pressure vessel is required because growth can be performed under 1 atmospheric pressure conditions; and (4) waste gas detoxification equipment is not required because only N2 gas is used and no toxic or flammable gases are used. Because of the above features (1) through (4), this is an effective crystal growth process from the perspective of ensuring the economics and safety of the facility.
Heuristic prediction of gas precipitation performance of self-excited oscillation cavity
Authors: Nie Songlin , Li Mingshuai , Ji Hui , Yin Fanglong , Ma Zhonghai
Published: August 2023

The precipitation of dissolved gas in oil is a challenging problem in pollution control of hydraulic systems. When the self-excited oscillation jet is formed, there are two low-pressure regions in the self-excited oscillation cavity, and the reduction in pressure causes the dissolved gas in the oil to precipitate out. Here, we investigated the effect of the self-excited oscillation cavity on the dissolution of dissolved gas in oil. We studied the gas precipitation performance of the self-excited oscillation cavity by simulating the pressure and velocity fields inside the cavity under different ratios of dimensionless structure parameters. The results indicated that parameter intervals for maintaining good gas precipitation performance of the self-excited oscillation cavity were d2/d1=2–2.4, D/d2=4–6, and D/L = 2. We then used a heuristic prediction algorithm (Genetic algorithm-backpropagation, GA-BP) to fit the simulation and experimental data, in which the root mean square error between the simulation and experimental data was only 2.45%. This indicated that the simulation of the flow field was reasonable, and that the GA-BP model performed well in predicting the gas precipitation performance of the self-excited oscillation cavity. Our results have important guiding significance for future studies on the gas precipitation performance of the self-excited oscillation cavity.
Voltage deficit in PV with suppressed recombination
Authors: Karpov Victor , Shvydka Diana
Published: August 2023

The observed open circuit voltages in best performing solar cells are explained outside of the recombination paradigm, based on such factors as electrostatic screening, Meyer–Neldel effect, and lateral nonuniformities. The underlying concept of suppressed recombination presents a long neglected alternative pathway to efficient photovoltaic. The criteria of suppressed recombination and effective charge carrier extraction are consistent with the data for best performing solar cells.
Metabolomic analysis reveals key metabolites and metabolic pathways in Suaeda salsa under salt and drought stress
Authors: Bao Jinbo , Liu Zhiyou , Ding Zhijie , Yisilam Gulbar , Wang Qiuyan , Tian Xinmin
Published: August 2023

Suaeda salsa is an important salt- and drought-tolerant plant with important ecological restoration roles. However, little is known about its underlying molecular regulatory mechanisms. Therefore, understanding the response mechanisms of plants to salt and drought stress is of great importance. In this study, metabolomics analysis was performed to evaluate the effects of salt and drought stress on S. salsa. The experiment consisted of three treatments: (1) control (CK); (2) salt stress (Ps); and (3) drought stress (Pd). The results showed that compared with the control group, S. salsa showed significant differences in phenotypes under salt and drought stress conditions. First, a total of 207 and 292 differential metabolites were identified in the Ps/CK and Pd/CK groups, respectively. Second, some soluble sugars and amino acids, such as raffinose, maltopentoses, D-altro-beptulose, D-proline, valine-proline, proline, tryptophan and glycine-L-leucine, showed increased activity under salt and drought stress conditions, suggesting that these metabolites may be responsible for salt and drought resistance in S. salsa. Third, the flavonoid biosynthetic and phenylalanine metabolic pathways were significantly enriched under both salt and drought stress conditions, indicating that these two metabolic pathways play important roles in salt and drought stress resistance in S. salsa. The findings of this study provide new insights into the salt and drought tolerance mechanisms of S. salsa.
Soliton Interactions with Different Dispersion Curve Functions in Heterogeneous Systems
Authors: Zhang Xinyi , Wu Ye
Published: August 2023

In practical optical communication systems, there are some factors that can affect transmission quality of optical solitons. The constant coefficient nonlinear Schrödinger (NLS) equation has been unable to meet the actual research needs. We need to use the variable coefficient NLS equation to simulate an actual system, so as to explore its potential application value. Based on the variable coefficient NLS equation, six dispersion decreasing fibers (DDFs) with different dispersion curve functions are used as transmission media to study generation and interaction of two solitons in an optical communication system. The two soliton interaction phenomena, such as the bound state solitons, are theoretically obtained. Moreover, the output characteristics of bound state solitons in different DDFs are discussed, which enriches the transmission phenomenon of two solitons in the optical communication system. This study has great application value in fields such as optical information processing devices, condensed matter physics, and plasma, and provides an indispensable theoretical basis for development of new optical devices.
Geometric analogy between quantum dynamics and curved space through quantum hydrodynamics
Authors: Shushi Tomer
Published: August 2023

In general relativity, the dynamics of objects is governed by the curvature of spacetime, which is caused by the presence of matter and energy. In contrast, in quantum mechanics, the dynamics is governed by the wavefunction, which completely describes the behavior of the particles. There is an ongoing effort to explore analogs of space and spacetime curvature in the context of quantum mechanics. Such analogies may reveal a deeper structure of quantum reality and its possible relations with Einstein’s theory of gravity. In this note, by coupling the non-relativistic Schrödinger equation with the heat equation and using the hydrodynamical formulation of quantum mechanics, we find that the dynamics of the particle is fully characterized by the normalized curvature of the wavefunction’s amplitude. Such a curvature obtains an analogy to the Ricci curvature of curved space in a Riemannian manifold. The proposed geometric correspondence provides a new pathway to explore quantum dynamics through the lens of differential geometry, the language of general relativity.
Trapping and sorting of nanoparticles by bowtie-nanohole plasmonic tweezers
Authors: Nie Yingdong , Xie Chaofeng , Zhu Guodong , Fang Yurui
Published: August 2023

Optical tweezers are a crucial tool for manipulating nanoscale objects, and have a wide range of applications in various fields. Bowtie-nanohole tweezers, a type of near-field optical tweezers, are particularly intriguing due to their strong near-field enhancement and unique characteristics. In this paper we provide a detailed discussion of the properties of bowtie-nanohole tweezers on trapping and sorting nanoparticles through theoretical and numerical results. It is discovered that the tweezers behave differently when trapping particles with varying refractive indices, leading to a discussion of sorting chiral particles. Moreover, the relative refractive index between the particles and the background solution greatly influences the trapping and sorting abilities of the tweezers. Finally, we investigate the performance of the tweezers at different wavelengths of incident light to determine the optimal working wavelength for trapping or sorting.
Theoretical and computational tools to model multistable gene regulatory networks
Authors: Bocci Federico , Jia Dongya , Nie Qing , Jolly Mohit Kumar , Onuchic José
Published: August 2023

The last decade has witnessed a surge of theoretical and computational models to describe the dynamics of complex gene regulatory networks, and how these interactions can give rise to multistable and heterogeneous cell populations. As the use of theoretical modeling to describe genetic and biochemical circuits becomes more widespread, theoreticians with mathematical and physical backgrounds routinely apply concepts from statistical physics, non-linear dynamics, and network theory to biological systems. This review aims at providing a clear overview of the most important methodologies applied in the field while highlighting current and future challenges. It also includes hands-on tutorials to solve and simulate some of the archetypical biological system models used in the field. Furthermore, we provide concrete examples from the existing literature for theoreticians that wish to explore this fast-developing field. Whenever possible, we highlight the similarities and differences between biochemical and regulatory networks and ‘classical’ systems typically studied in non-equilibrium statistical and quantum mechanics.
New phase diagram for low hysteresis response of a coiled shape memory alloy actuator
Authors: Hyeon Kyujin , Kyung Ki-Uk
Published: August 2023

We demonstrate a new phase diagram describing the responses of shape memory alloy (SMA) spring actuators. The SMA spring actuator has a wide range of temperatures for phase transitions and responses with low hysteresis. To describe these specific responses of the SMA spring actuator, a new phase diagram with an overlapping layer is proposed. In the overlapping layer, even if it changes from a heating phase to a cooling phase or vice versa, a phase transition occurs whenever the temperature of the SMA changes. Because there is no region in which only the temperature changes without a force changes, the hysteresis is reduced. The overlapping layer is formed by changing the properties of the SMA when fabricating the spring actuator. One of the properties that change in the SMA is the amount of latent heat when the phase transition occurs. The latent heat of the SMA spring is significantly low compared to that of the SMA wire due to the plasticity produced by the stress applied to form the spring shape. Therefore, there will be a tradeoff between the amount of the phase transition and the hysteresis of the SMA actuator.
Electrochemical performance of ionic polymer metal composite under tensile loading
Authors: Napollion Liya , Kim Kwang J
Published: August 2023

Cracks in polymer composites can lead to premature failure, which can be disastrous for polymer-based energy storage devices. Detecting these cracks is essential to guarantee the reliability and safety of such devices. However, detecting cracks in composite polymers such as ionic polymer metal composites (IPMCs) is a challenging task, which makes it difficult to ensure their performance and safety. The overall goal of this study is to investigate the effect of cracks or damage caused by tensile loading on the mechanical properties and electrochemical characteristics of IPMC based capacitors. During tensile testing, the deformation of the IPMC strips causes changes in the ion distribution and concentration in the polymer matrix, influencing the performance of the material. The measurements were conducted utilizing electrochemical impedance spectroscopy at a room temperature (

21

∘

C

) and frequency range of 10 KHz to 1 Hz. The method utilized in this study proved to be easy and quick with consistent results. The IPMC capacitor was found to increase its capacitance after major cracking in the Pt electrodes from high tensile mechanical loads. Furthermore, at lower frequency range (<100 Hz), the real (

ε

′

) and imaginary (

ε

′
′

) part of permittivity increase with the addition of loads. This displays that the dielectric property of the material is affected due to the increasing of the loads. It is concluded that, at frequencies above 100 Hz, the permittivity is weakly load dependent.