bluuebunny/crossref_metadata_2025 huggingface dataset:
Low-temperature preservation of sterlet reproductive cells (Acipenser ruthenus Linnaeus, 1758) by the acoustic-mechanical influence method
Authors: Ponomareva Elena , Matrosov Andrey , Kovalenko Matvey , Rudoy Dmitry , Pakhomov Viktor
Published: December 2023

To preserve reproductive cells of rare and endangered species of sturgeon fish using low-temperature cryopreservation methods, acoustic-mechanical impact with the use of piezoactuators was used. As a result of the research, the optimum parameters of signal frequency and time of impact on sturgeon cells were established, at which a high survival rate of sperm after defrosting was observed.Using mathematical modelling, the mechanism of acoustic-mechanical influence was studied, which consists in the wave and mechanical action created by the piezoactuator, which leads to acceleration of the process of diffusion of the cryoprotector inside the cells.For the first time a new methodological approach to low-temperature preservation of fish reproductive cells with the use of acoustic-mechanical impact has been proposed, which makes it possible to preserve genetic material with high survival rate and quality indicators.
Innovative solutions in creating noise maps in cities
Authors: Suyunov Abdusali , Tukhtamishev Shukhrat , Suyunov Shukhrat , Manoev Sanat , Samankulov Shukhrat
Published: December 2023

This article describes the procedure for performing geodetic and cartographic mapping of urban noise maps. Modern geodetic (shumometric) devices used to measure noise frequencies, and the coordinates of the limit of noise impact on urban buildings and structures using technology and processing of measured data using modern geodetic software (Panorama). With the help of the panorama program, noise maps of the noisy streets of Samarkand were created based on the legend. The scientific significance of the results of the study lies in the fact that the geodetic bases are created using satellites, that is, instead of the bases created along the road, sound level meters are installed and noise measurements are taken. This is due to the fact that a method has been developed for creating noise maps using programs and technologies based on measured noise propagation data, as a result of which a method has been developed for describing noise propagation with cartographic symbols and it has become possible to use them on a global scale. The practical significance of the research results lies in the fact that the PANORAMA program created modern information and relevant opportunities based on space data, developed noise maps of the streets of Samarkand, M. Ulugbek, A. Rudakiy, A. Beruniy, Registan, and on these maps it can be seen that the decibels of noise in the city are increasing every year, determined by the fact that it will serve as an important mapping resource for the future.
Implementation of world and Russian indicators of the “smart city” concept in the environmental parameters of the development of urbanized territories
Authors: Matveeva Anna , Boltonogova Evgeniya , Kirillov Sergey , Slipenchuk Mikhail , Kirichkova Irina
Published: December 2023

In recent years, one can observe more intensive anthropogenic development of urban areas in the world and in the Russian Federation. This has led to the growth of urban agglomerations and a high level of urbanization, which negatively affects not only the environment, but also the social and economic components. One can note the trend in the development of digital technologies. The introduction of new technologies aimed at improving the lives of the population and creating sustainable development of the subject also has an environmental context. There is a noticeable similarity between the criteria of a “Smart City” and the goals of achieving sustainable development. They have a common direction - the creation of a comfortable and sustainable urban space, where the environmental, economic and social components will function in a single system and balance each other. But the main limitation of the implementation of this concept in Russia is the lack of funding and its uneven distribution across regions. The smart city management system should be a complex whole of interconnected elements, where the functioning of a separate part ensures the operation of the entire system as a whole. The result should be an increase in the efficient functioning of government bodies and an improvement in the quality of life of the population preserving the environment.
Real-time tree physiology monitoring system
Authors: Kabonen Alexey , Kuvshinov Dmitry , Dimitrov Vyacheslav
Published: December 2023

Electronic devices have been developed to operate in real time with an alarm on the streets of Diptychs. The devices are IoT-platforms based on the ESP-32 microprocessor, equipped with a LoRa transceiver to transmit data to a module that collects tree data and sends it to the cloud using GSM/GPRS. Pilot implementation will take place in 2023 on the territory of the Botanical Garden of Petrozavodsk State University (Republic of Karelia, Russia). The work was carried out with the aim of studying the seasonal dynamics of Malus domestica under growing conditions in the extreme territories of Northern Russia. The research results show that on May 16-18, during the characteristic phenological phase «The beginning of reddening of leaves» (ВВСН 11) at an average daily air temperature of +5.7°C, a sum of temperatures of 487°C and an average daily temperature of 325°C. The phenophase «Beginning of flowering» (ВВСН 61) was noted on May 28 at an air temperature of +13.3 °C. The phenophase «Beginning of fruit ripening» (ВВСН 81-86) was noted on August 16. The beginning of the increase in trunk diameter, according to the distant number, was noted on June 15-20, the growth lasted until July 20-25 and amounted to about 3 mm. The research results showed that the species Malus Domestica may be preferable for introduction into the culture of northern fruit growing.
History and prospects of development of eco-tourism in Kashkadarya region
Authors: Ergasheva Yu.A. , Eralov A.J.
Published: December 2023

This article talks about the history and prospects of ecological tourism development in Kashkadarya region. Based on archival data, the author analyzed the problem based on available scientific literature and studied the specific aspects of the history and prospects of the development of ecological tourism in Kashkadarya regions.
Problems of the electric power system of the municipal electric transport of Novorossiysk
Authors: Chernysheva Natalya , Frantseva Tatyana , Sukhomlinova Aleksandra , Khmara Ivan , Drozhzhin Igor
Published: December 2023

A developed public transport system, in which the types of municipal electric transport (trams, trolleybuses, etc.) are of paramount importance, ensures a reduction in the load on the environment – this pattern is one of the principles of such a scientific direction as sustainable development. However, for the functioning of any structure, the use of energy resources is necessary – in the case of a trolleybus transport complex, the electric power system acts as a resource. This information provided is a description of the principles of operation of the Novorossiysk enterprise, on which the maintenance of trolleybus rolling stock and elements of the electric power infrastructure are based. In addition, the publication discusses the problems faced by the municipal electric transport system.
Model of interaction of a steam-water cavity with a molten metal near a solid wall
Authors: Melikhov O.I. , Melikhov V.I. , Finoshkina D.V.
Published: December 2023

To evaluate the consequences of an accidental rupture of a steam generator heat exchange tube in a reactor with a heavy liquid metal coolant, a mathematical model of the interaction of a steam-water cavity with molten metal near a solid wall was developed. The melt flow is considered as a potential flow of an incompressible fluid. The heat exchange between the melt and the steam-water mixture is not taken into account. The steam-water mixture is modeled by an equilibrium two-phase model. It is believed that the evolution of the steam-water cavity is an isentropic process. The numerical implementation of the mathematical model was performed using the boundary element method. Verification of the developed model using a numerical solution of a spherically symmetric problem of the interaction of a spherical steam-water cavity with a melt in infinite space, obtained using the Rayleigh-Plesset equation, showed good agreement between the solutions obtained by different methods. Using the developed model, a test calculation of the interaction of a steam-water cavity with the surrounding molten metal near a solid wall was performed. Analysis of the calculation revealed several stages of this interaction
An Atypical Presentation of Decubitis Angina in a Patient with Coronary Artery Disease and Aortic Regurgitation: Case Report
Authors: Yetkin Ertan , Atmaca Hasan , Yalta Kenan
Published: December 2023

Decubitis angina briefly refers to a pain occurring during the night or in recumbent position. Herewith, we present a case of decubitis angina occurring immediately after lying down in a patient with coronary artery disease and aortic regurgitation. The patient was successfully treated by percutaneous coronary intervention. It should be kept in mind that early-onset chest pain immediately after lying down might be a sign of myocardial ischemia or acute coronary syndrome especially in the presence of coronary artery disease and aortic regurgitation.
Income illusions: challenging the high yield stock narrative
Authors: Chen Yin , Israelov Roni
Published: December 2023

While stocks with high dividends have historically outperformed those with low dividends, we show that the difference can be completely explained by a set of well-known factors including value, quality and defensive. Applying a dividend filter to a portfolio of strategies having high exposure to these factors yields sub-optimal results. To test whether incorporating dividend yields can improve the performance of long-only factor portfolios, we construct a set of dividend-favored long-only factor portfolios with a heuristic rebalance algorithm and find that their after-tax net returns are lower than the dividend-agnostic counterparts. Collectively our results indicate that long-only active investors are better off loading directly on value, quality and defensive factors than purposely tilting their portfolios toward high-dividend stocks.
Development of the potential of the digital economy of Russian regions through artificial intelligence humanisation
Authors: Ekimova Ksenia V.
Published: December 2023

This paper is aimed at balancing the interests of business and society in the digital economy, to reduce the social risks of the Fourth Industrial Revolution. The goal of this paper is to study the experience and prospects of the humanisation of AI through the improvement of the practice of corporate social responsibility in Russia. By the example of the experience of Russian regions in 2021, we use econometric modelling to prove that the digital regional economy has a large potential in the sphere of humanisation of AI. The potential for the humanisation of AI in the digital economy of Russian regions is determined by responsible innovations, responsible production and logistics, as well as responsible marketing and sales, which contribute to the implementation of SDGs 9–12. The theoretical significance of the paper lies in its presenting smart region as a socio-economic environment for the humanisation of AI. The scientific novelty of the paper lies in its offering a new—meso-level—view of the humanisation of AI. The advantages of the new view include, first, consideration of socio-economic conditions for the humanisation of AI in a region; second, the most precise identification and correct measuring of the consequences of humanisation of AI for the quality of life in a region. The practical significance of the research results consists in the fact that the new proposed approach to the humanisation of AI, which implies public administration of this process at the level of a region, allows accelerating the considered process.
Nonlinear inverse bremsstrahlung absorption in magnetized laser-fusion plasma
Authors: Malim Roumaissa , Sid Abdelaziz , Moumni Mustafa , Boultif Oussama , Ghezal Abdenasser
Published: December 2023

The nonlinear inverse bremsstrahlung absorption (NLIBA) in magnetized plasma has been investigated within the framework of relativistic kinetic theory. Collisions are described by an improved Krook collision term that accounts for relativistic effects and the Landau microscopic collision form. The non-linearity considered in this paper arises from the anisotropy in electron momentum space in the plasma that is heated by an intense laser pulse. The absorption is explicitly expressed, under reasonable approximations, as a function of the plasma, laser pulse, and magnetic field parameters. Numerical treatment of the model equations shows that absorption increases with laser intensity but decreases with plasma temperature and laser wavelength. It has been shown that the polarization of the laser wave has a significant influence on absorption for high-intense magnetic fields used in magneto-inertial fusion (MIF) experiments. Nonlinear effects clearly reduce absorption for laser intensities comparable to the characteristic intensity, I0=me2c3ε0ωL2/e2, where me is the electron mass, c is the speed of light in vacuum, ɛ0 is the electric permittivity of free space, ωL is the laser wave frequency, and e is the elementary electric charge. Within the intensity I ≪ I0 and laser wavelength in the micro-meter range (λ ∼ μm), relativistic effects appear in the third order of absorption. These findings allow for the optimization of laser pulse parameters to achieve efficient absorption in MIF experiments.
Electric field-dependent photoexcited spin-polarized electron transport in Bi2Se3 topological insulator
Authors: Hua Chen-Wei , Huang Jian-Jang
Published: December 2023

Three-dimensional (3D) topological insulators (TIs) exhibit spin-polarized surface states in which the spin of electrons is locked to their momentum. The helical surface states can be explored from circularly polarized light-induced spin photocurrent, a phenomenon called circular photogalvanic effect (CPGE). In this work, we fabricate a TI transistor with the Bi2Se3 channel layer synthesized using vapor deposition. The photocurrent response of Bi2Se3 TI is characterized under horizontal and longitudinal electric fields. CPGE and linear photogalvanic effect (LPGE) contribute to the surface state photocurrent at room temperature. The longitudinal electric field provides kinetic energy to the electrons so that the transition of electrons to higher energy bands in momentum space occurs. Under a photon excitation with the energy far above the TI bandgap, we observed a photocurrent difference between left and right circularly polarized light excitation. The photocurrent variation with gate voltage (longitudinal field) is also investigated. Adjusting the Fermi level with the gate bias leads to changes in the population of bulk state carriers and spin electrons in surface states. By shifting the gate bias toward negative, the CPGE current increases because of the reduced scattering with bulk carriers. Our work reveals that longitudinal and horizontal electric fields can manipulate the helical spin-polarized photocurrent of Bi2Se3. From the asymmetry of circularly polarized photoconductive differential current (CPDC) under the horizontal field, we found evidence of spin-polarized electron transition to other conduction band valleys at room temperature under a high-energy photon excitation.
Harmonic models and molecular dynamics simulations of isomorph behavior of Lennard-Jones fluids: Excess entropy and high temperature limiting behavior
Authors: Heyes D. M. , Dini D. , Pieprzyk S. , Brańka A. C.
Published: December 2023

Henchman’s approximate harmonic model of liquids is extended to predict the thermodynamic behavior along lines of constant excess entropy (“isomorphs”) in the liquid and supercritical fluid regimes of the Lennard-Jones (LJ) potential phase diagram. Simple analytic expressions based on harmonic cell models of fluids are derived for the isomorph lines, one accurate version of which only requires as input parameters the average repulsive and attractive parts of the potential energy per particle at a single reference state point on the isomorph. The new harmonic cell routes for generating the isomorph lines are compared with those predicted by the literature molecular dynamics (MD) methods, the small step MD method giving typically the best agreement over a wide density and temperature range. Four routes to calculate the excess entropy in the MD simulations are compared, which includes employing Henchman’s formulation, Widom’s particle insertion method, thermodynamic integration, and parameterized LJ equations of state. The thermodynamic integration method proves to be the most computationally efficient. The excess entropy is resolved into contributions from the repulsive and attractive parts of the potential. The repulsive and attractive components of the potential energy, excess Helmholtz free energy, and excess entropy along a fluid isomorph are predicted to vary as ∼T−1/2 in the high temperature limit by an extension of classical inverse power potential perturbation theory statistical mechanics, trends that are confirmed by the MD simulations.
The mitochondrial ATP synthase is a negative regulator of the mitochondrial permeability transition pore
Authors: Pekson Ryan , Liang Felix G. , Axelrod Joshua L. , Lee Jaehoon , Qin Dongze , Wittig Andre J. H. , Paulino Victor M. , Zheng Min , Peixoto Pablo M. , Kitsis Richard N.
Published: December 2023

The mitochondrial permeability transition pore (mPTP) is a channel in the inner mitochondrial membrane whose sustained opening in response to elevated mitochondrial matrix Ca
2+
concentrations triggers necrotic cell death. The molecular identity of mPTP is unknown. One proposed candidate is the mitochondrial ATP synthase, whose canonical function is to generate most ATP in multicellular organisms. Here, we present mitochondrial, cellular, and in vivo evidence that, rather than serving as mPTP, the mitochondrial ATP synthase inhibits this pore. Our studies confirm previous work showing persistence of mPTP in HAP1 cell lines lacking an assembled mitochondrial ATP synthase. Unexpectedly, however, we observe that Ca
2+
-induced pore opening is markedly sensitized by loss of the mitochondrial ATP synthase. Further, mPTP opening in cells lacking the mitochondrial ATP synthase is desensitized by pharmacological inhibition and genetic depletion of the mitochondrial
cis-trans
prolyl isomerase cyclophilin D as in wild-type cells, indicating that cyclophilin D can modulate mPTP through substrates other than subunits in the assembled mitochondrial ATP synthase. Mitoplast patch clamping studies showed that mPTP channel conductance was unaffected by loss of the mitochondrial ATP synthase but still blocked by cyclophilin D inhibition. Cardiac mitochondria from mice whose heart muscle cells we engineered deficient in the mitochondrial ATP synthase also demonstrate sensitization of Ca
2+
-induced mPTP opening and desensitization by cyclophilin D inhibition. Further, these mice exhibit strikingly larger myocardial infarctions when challenged with ischemia/reperfusion in vivo. We conclude that the mitochondrial ATP synthase does not function as mPTP and instead negatively regulates this pore.
Direct observation of the effects of chemical fixation in MNT-1 cells: A SE-ADM and Raman study
Authors: Mastrangelo Rosangela , Okada Tomoko , Ogura Taku , Ogura Toshihiko , Baglioni Piero
Published: December 2023

Aldehydes fixation was accidentally discovered in the early 20th century and soon became a widely adopted practice in the histological field, due to an excellent staining enhancement in tissues imaging. However, the fixation process itself entails cell proteins denaturation and crosslinking. The possible presence of artifacts, that depends on the specific system under observation, must therefore be considered to avoid data misinterpretation. This contribution takes advantage of scanning electron assisted-dielectric microscopy (SE-ADM) and Raman 2D imaging to reveal the possible presence and the nature of artifacts in unstained, and paraformldehyde, PFA, fixed MNT-1 cells. The high resolution of the innovative SE-ADM technique allowed the identification of globular protein clusters in the cell cytoplasm, formed after protein denaturation and crosslinking. Concurrently, SE-ADM images showed a preferential melanosome adsorption on the cluster’s outer surface. The micron-sized aggregates were discernible in Raman 2D images, as the melanosomes signal, extracted through 2D principal component analysis, unequivocally mapped their location and distribution within the cells, appearing randomly distributed in the cytoplasm. Protein clusters were not observed in living MNT-1 cells. In this case, mature melanosomes accumulate preferentially at the cell periphery and are more closely packed than in fixed cells. Our results show that, although PFA does not affect the melanin structure, it disrupts melanosome distribution within the cells. Proteins secondary structure, conversely, is partially lost, as shown by the Raman signals related to α-helix, β-sheets, and specific amino acids that significantly decrease after the PFA treatment.
Rate-induced tipping in complex high-dimensional ecological networks
Authors: Panahi Shirin , Do Younghae , Hastings Alan , Lai Ying-Cheng
Published: December 2023

In an ecosystem, environmental changes as a result of natural and human processes can cause some key parameters of the system to change with time. Depending on how fast such a parameter changes, a tipping point can occur. Existing works on rate-induced tipping, or R-tipping, offered a theoretical way to study this phenomenon but from a local dynamical point of view, revealing, e.g., the existence of a critical rate for some specific initial condition above which a tipping point will occur. As ecosystems are subject to constant disturbances and can drift away from their equilibrium point, it is necessary to study R-tipping from a global perspective in terms of the initial conditions in the entire relevant phase space region. In particular, we introduce the notion of the probability of R-tipping defined for initial conditions taken from the whole relevant phase space. Using a number of real-world, complex mutualistic networks as a paradigm, we find a scaling law between this probability and the rate of parameter change and provide a geometric theory to explain the law. The real-world implication is that even a slow parameter change can lead to a system collapse with catastrophic consequences. In fact, to mitigate the environmental changes by merely slowing down the parameter drift may not always be effective: Only when the rate of parameter change is reduced to practically zero would the tipping be avoided. Our global dynamics approach offers a more complete and physically meaningful way to understand the important phenomenon of R-tipping.
Synaptic plasticity at the dentate gyrus granule cell to somatostatin-expressing interneuron synapses supports object location memory
Authors: Grigoryan Gayane , Harada Harumi , Knobloch-Bollmann H. Sophie , Kilias Antje , Kaufhold Dorthe , Kulik Akos , Eyre Mark D. , Bartos Marlene
Published: December 2023

Somatostatin-expressing interneurons (SOMIs) in the mouse dentate gyrus (DG) receive feedforward excitation from granule cell (GC) mossy fiber (MF) synapses and provide feedback lateral inhibition onto GC dendrites to support environment representation in the DG network. Although this microcircuitry has been implicated in memory formation, little is known about activity-dependent plastic changes at MF-SOMI synapses and their influence on behavior. Here, we report that the metabotropic glutamate receptor 1α (mGluR1α) is required for the induction of associative long-term potentiation (LTP) at MF-SOMI synapses. Pharmacological block of mGluR1α, but not mGluR5, prevented synaptic weight changes. LTP at MF-SOMI synapses was postsynaptically induced, required increased intracellular Ca
2+
, involved G-protein-mediated and Ca
2+
-dependent (extracellular signal-regulated kinase) ERK1/2 pathways, and the activation of NMDA receptors. Specific knockdown of mGluR1α in DG-SOMIs by small hairpin RNA expression prevented MF-SOMI LTP, reduced SOMI recruitment, and impaired object location memory. Thus, postsynaptic mGluR1α-mediated MF-plasticity at SOMI input synapses critically supports DG-dependent mnemonic functions.
Myosin-binding protein H-like regulates myosin-binding protein distribution and function in atrial cardiomyocytes
Authors: Barefield David Y. , Tonino Paola , Woulfe Kathleen C. , Rahmanseresht Sheema , O’Leary Thomas S. , Burnham Hope V. , Wasserstrom J. Andrew , Kirk Jonathan A. , Previs Michael J. , Granzier Henk L. , McNally Elizabeth M.
Published: December 2023

Mutations in atrial-enriched genes can cause a primary atrial myopathy that can contribute to overall cardiovascular dysfunction.
MYBPHL
encodes myosin-binding protein H-like (MyBP-HL), an atrial sarcomere protein that shares domain homology with the carboxy-terminus of cardiac myosin-binding protein-C (cMyBP-C). The function of MyBP-HL and the relationship between MyBP-HL and cMyBP-C is unknown. To decipher the roles of MyBP-HL, we used structured illumination microscopy, immuno-electron microscopy, and mass spectrometry to establish the localization and stoichiometry of MyBP-HL. We found levels of cMyBP-C, a major regulator of myosin function, were half as abundant compared to levels in the ventricle. In genetic mouse models, loss of MyBP-HL doubled cMyBP-C abundance in the atria, and loss of cMyBP-C doubled MyBP-HL abundance in the atria. Structured illumination microscopy showed that both proteins colocalize in the C-zone of the A-band, with MyBP-HL enriched closer to the M-line. Immuno-electron microscopy of mouse atria showed MyBP-HL strongly localized 161 nm from the M-line, consistent with localization to the third 43 nm repeat of myosin heads. Both cMyBP-C and MyBP-HL had less-defined sarcomere localization in the atria compared to ventricle, yet areas with the expected 43 nm repeat distance were observed for both proteins. Isometric force measurements taken from control and
Mybphl
null single atrial myofibrils revealed that loss of
Mybphl
accelerated the linear phase of relaxation. These findings support a mechanism where MyBP-HL regulates cMyBP-C abundance to alter the kinetics of sarcomere relaxation in atrial sarcomeres.
Intraneuronal β-amyloid impaired mitochondrial proteostasis through the impact on LONP1
Authors: Wang Wenzhang , Ma Xiaopin , Bhatta Sabina , Shao Changjuan , Zhao Fanpeng , Fujioka Hisashi , Torres Sandy , Wu Fengqin , Zhu Xiongwei
Published: December 2023

Mitochondrial dysfunction plays a critical role in the pathogenesis of Alzheimer’s disease (AD). Mitochondrial proteostasis regulated by chaperones and proteases in each compartment of mitochondria is critical for mitochondrial function, and it is suspected that mitochondrial proteostasis deficits may be involved in mitochondrial dysfunction in AD. In this study, we identified LONP1, an ATP-dependent protease in the matrix, as a top Aβ42 interacting mitochondrial protein through an unbiased screening and found significantly decreased LONP1 expression and extensive mitochondrial proteostasis deficits in AD experimental models both in vitro and in vivo, as well as in the brain of AD patients. Impaired METTL3-m
6
A signaling contributed at least in part to Aβ42-induced LONP1 reduction. Moreover, Aβ42 interaction with LONP1 impaired the assembly and protease activity of LONP1 both in vitro and in vivo. Importantly, LONP1 knockdown caused mitochondrial proteostasis deficits and dysfunction in neurons, while restored expression of LONP1 in neurons expressing intracellular Aβ and in the brain of CRND8 APP transgenic mice rescued Aβ-induced mitochondrial deficits and cognitive deficits. These results demonstrated a critical role of LONP1 in disturbed mitochondrial proteostasis and mitochondrial dysfunction in AD and revealed a mechanism underlying intracellular Aβ42-induced mitochondrial toxicity through its impact on LONP1 and mitochondrial proteostasis.
Beyond antiviral: Interferon induced by bacteria maintains tolerance in the gut
Authors: Yang Yi , Cadwell Ken
Published: December 2023

Type I interferons are best known for their antiviral role. Here, Ayala et al. (https://doi.org/10.1084/jem.20230063) reveal that commensal bacteria elicit tonic type I interferons to prime dendritic cells and induce regulatory T cells that maintain a tolerogenic intestinal milieu.
Thermal transport mechanism of 4H–SiC/SiO2 heterostructures: a molecular dynamics study
Authors: Xiao Chengdi , Xing Zhenguo , Shu Wenqiang , Zhang Haitao , Rao Xixin
Published: December 2023

Silicon carbide (SiC) is widely used in high-frequency, high-speed, and high-power applications such as power electronics, rail transportation, new energy vehicles, and aerospace. However, the thermal properties of the SiC/SiO2 interface, which is commonly found in SiC-based devices, are not yet fully understood. This study aims to investigate the influence of temperature and interface coupling strength on the interface thermal resistance (ITR) of 4H-SiC/SiO2 using non-equilibrium molecular dynamics simulations. Both crystalline and amorphous SiO2, as well as two interface contact modes (Si-terminated and C-terminated), have also been considered. The results reveal that the ITR of 4H-SiC/SiO2 is significantly affected by the interface coupling strength and contact modes. Under strong interface coupling conditions, the ITR for Si-terminated and C-terminated contacts modes of 4H-SiC/SiO2 interfaces are 8.077 × 10−10 m2KW−1 and 6.835 × 10−10 m2KW−1, respectively. However, under weak interface coupling conditions, these values increase to 10.142 × 10−10 m2KW−1 and 7.785 × 10−10 m2KW−1, respectively. Regardless of whether SiO2 is crystalline or amorphous, the ITR of the 4H-SiC/SiO2 interface exhibits a similar trend with increasing temperature (from 300 to 700 K). Additionally, the ITR of the amorphous SiO2 interface is smaller than that of the crystalline SiO2 interface under both strong and weak coupling conditions. To gain insights into the heat transport mechanism, the phonon density of states was analyzed to examine the phonon spectral characteristics under varying coupling strengths. These findings have implications for enhancing the thermal management and heat dissipation of SiC devices, providing a framework for controlling interface phonon scattering, and informing the thermal design of nanodevices.
A novel enhanced chaos based present lightweight cipher scheme
Authors: Abdelli Ali , El hadj Youssef Wajih , Kharroubi Fehmi , Khriji Lazhar , Machhout Mohsen
Published: December 2023

Lightweight ciphers have been developed to meet the rising need for secure communication in environments with limited resources. These ciphers provide robust encryption while ensuring efficient computation. Our paper introduces a new enhanced PRESENT lightweight cipher that utilizes chaotic systems to enhance its robustness and randomness while retaining the simplicity and compactness of the original cipher. By integrating chaotic maps into the cipher's core components, we improve its resistance against advanced cryptanalysis, such as differential, Salt & Peppers Noise (SPN), and loss data attacks. We also optimize the design for computational efficiency, making it suitable for deployment in devices with limited resources. Through extensive simulations and comparative analyses, we demonstrate the superiority of our enhanced cipher in terms of security and efficiency compared to other state-of-the-art lightweight ciphers. Our research contributes to the advancement of lightweight cryptography and provides a promising solution for secure communication in resource-constrained environments.
Numerical solution of the Whitham-Broer-Kaup shallow water equation by quartic B-spline collocation method
Authors: Sabawi Younis A , Hamad Hoshman Q
Published: December 2023

This paper introduces a novel quartic B-spline collocation method to address the coupled Whitham–Broer–Kaup (WBK) problem. The WBK problem is a topic of interest in the study of nonlinear wave phenomena and has applications in various fields, including fluid dynamics, plasma physics, and nonlinear optics. The method combines spatial quartic B-spline scheme discretization, and Crank–Nicolson temporal discretization. It is unconditionally stable as proven by the Von-Neumann technique. Numerical examples demonstrate the method’s superior accuracy compared to existing solutions. Error analysis employs

l

2

and

l

∞

norms, while the method exhibits high computational efficiency. The nonlinearity is managed through Rubin-Graves linearization. Comparisons with prior approaches highlight its efficiency, stability, adaptability to complex problems. The quartic B-spline method is well-suited for simulating fluid flow phenomena in shallow water scenarios, offering high accuracy and low computational cost.
Selective enhancement of difference sideband generation in a quadratically coupled optomechanical system with mechanical driving
Authors: Wang Xiao-Yun , Sun Xiao-Wei , Liu Zi-Jiang , Si Liu-Gang
Published: December 2023

We explore theoretically the generation and selective enhancement of difference sidebands in a quadratically coupled optomechanical system in which the membrane is driven resonantly by an additional coherent mechanical driving field. We show that the generation of frequency components at the difference sideband is directly related to the nonlinear optomechanical interactions under two-phonon resonance condition, while an additional weak coherent mechanical driving field acting on the membrane can considerably establish a selective enhancement of difference sideband generation (DSG). Our analytical solution with experimentally achievable parameters demonstrates that even if the input power of the control field is relatively low DSG can be induced and greatly enhanced when the matching conditions are satisfied. It also indicates that the efficiencies of upper difference sideband generation (UDSG) and lower difference sideband generation (LDSG) can be selectively increased about three orders by properly adjusting the frequency and amplitude of the weakly coherent mechanical driving field. Furthermore, we also show that the matching conditions of UDSG and LDSG are modified by the weakly coherent mechanical driving field. The present investigation may help to achieve the practical application of DSG relevant to nonlinear optics, chip-scale optical communications, and precision measurement.
The Jacobi last multiplier, Lagrangian and Hamiltonian for Levinson–Smith type equations
Authors: Mitra Shreya , Ghose-Choudhury A , Poddar Sujoy , Garai Sudip , Guha Partha
Published: December 2023

We derive the Jacobi last multiplier for second-order ordinary differential equations of the Levinson–Smith type by using a combination of previous techniques employed for the Liénard-I and II classes of equations. This opens up the possibility for a Lagrangian or Hamiltonian description of the systems governed by the Levinson–Smith type of equations as well as simplifying the problem of finding first integrals of motion. The procedure has been illustrated by a number of suitable examples alongwith Kamke's equation with explicit time dependent coefficients.
The quantum internet: an efficient stabilizer states distribution scheme
Authors: Koudia Seid
Published: December 2023

Quantum networks are a fundamental component of quantum technologies, playing a pivotal role in advancing distributed quantum computing and laying the groundwork for the future quantum internet. They offer a scalable modular architecture for quantum chips and support infrastructure for measurement-based quantum computing. Furthermore, quantum networks serve as the backbone of the quantum internet, ensuring high levels of security. Notably, the advantages of quantum networks in communication are contingent upon entanglement distribution, which faces challenges such as high latency in protocols relying on Bell pair distribution and bipartite entanglement swapping. Additionally, algorithms designed for multipartite entanglement routing encounter intractability issues, rendering them unsolvable within polynomial time. In this paper, we explore a novel approach to distribute graph states in quantum networks, leveraging local quantum coding (LQC) isometries and multipartite states transfer. We also present single-use bounds for stabilizer states distribution. Analogous to network coding, these bounds are attainable when appropriate isometries and stabilizer codes are selected for relay nodes, resulting in reduced latency in entanglement distribution. We further demonstrate the protocol’s advantages across various network performance metrics.
Energy calibration of silicon drift detector - based spectrometer at ADITYA-U
Authors: Purohit S , Taunk Y , Gupta M K , Garg K
Published: December 2023

The Tokamak plasma start-up is the first process to have a successful Tokamak plasma discharge. Considering the start-up condition, high electric field and neutral density with the absence of flux surfaces an enhanced electron transport to the Plasma-Facing Components (PFC) or the inner vessel wall is expected. Such electron excursion under an applied electric field induces electromagnetic emission, especially in the x-ray region. Such emission is important as it gives vital information about the initial condition of the plasma start-up and the potential for energy loss to the PFC/vessel walls. A Silicon Drift Detector (SDD) based soft x-ray (SX) spectrometer is installed at the ADITYA-U tokamak, operating within the range of 1–30 keV generating a 4 K channel spectrum. The energy calibration, spectra transformation from channel space to the energy space, is a pre-requisite for any spectroscopic measurement. The calibration is performed by natural radioactive sources 241Am, 109Cd, 133Ba, and 55Fe having micro-curie strength. Two-point and multipoint calibrations are applied to the SDD spectra. The results from the two processes establish that the multipoint calibration works well for the identification of the photon energy due to the realization of the detector linearity for a wider band.
Analysis of fusion cross-section and S-factor of 13C + 12,13C reactions for different density distributions at astrophysical energies
Authors: Aygun Murat , Kocak Gokhan
Published: December 2023

The effect of the various density distributions on 13C + 12,13C reactions is investigated by using the optical model at energies near and below Coulomb barrier. For this purpose, five different density distributions of the 12C and 13C nuclei are used to produce the real potential over the double folding model. To make a comprehensive analysis, the fusion cross-sections, S-factor and elastic cross-sections are simultaneously analyzed at astrophysical energies. It is seen that the theoretical results are in good agreement with the experimental data. In this study, the hindrance characteristics of the S-factors for the 13C + 12,13C reactions are also examined at low energies, and hindrance behavior is not observed.
Demonstration of 82% relaxed In0.18Ga0.82N on porous GaN pseudo-substrate by plasma-assisted molecular beam epitaxy
Authors: Khan Kamruzzaman , Wurm Christian , Collins Henry , Muthuraj Vineeta R. , Khan Md Irfan , Lee Cindy , Keller Stacia , Ahmadi Elaheh
Published: December 2023

In this study, the impact of InGaN film thickness and different compositionally graded structures on InGaN relaxation grown on tiled GaN-on-porous-GaN pseudo substrates (PSs) were studied. In addition, the impact of the degree of porosification on the In incorporation and relaxation of InGaN were examined. 82% relaxed 1μm thick In0.18Ga0.82N, which is equivalent to a fully relaxed In-composition of 15%, on porous GaN PS was obtained. Additionally, multi-quantum wells (MQWs) grown on the MBE InGaN-on-porous GaN base layers by MOCVD showed ∼85 nm redshift in comparison with MQWs grown on planar GaN. The developed InGaN-on-porous-GaN PSs can provide an alternative route to grow MQW with a high In content which is essential for high-efficiency nitride-based red LEDs.
Hemispherical power asymmetry in intensity and polarization for Planck PR4 data
Authors: Gimeno-Amo C. , Barreiro R.B. , Martínez-González E. , Marcos-Caballero A.
Published: December 2023

One of the foundations of the Standard Model of Cosmology is statistical isotropy, which can be tested, among other probes, through the study of the Cosmic Microwave Background (CMB). However, a hemispherical power asymmetry on large scales has been reported for WMAP and Planck data by different works.
The statistical significance is above 3σ for temperature, suggesting a directional dependence of the local power spectrum, and thus a feature beyond the ΛCDM model. With the third release of the Planck data (PR3), a new analysis was performed including the E-mode polarization maps, finding an asymmetry at a modest level of significance. In this work, we perform an asymmetry analysis in intensity and polarization maps for the latest Planck processing pipeline (PR4). We obtain similar results to those obtained with PR3, with a slightly lower significance (2.8% for the Sevem method)
for the amplitude of the E-mode local variance dipole as well as a significant variability with the considered mask.
In addition, a hint of a possible T-E alignment between the asymmetry axes is found at the level of ∼ 5%. For the analysis, we have implemented an alternative inpainting approach in order to get an accurate reconstruction of the E-modes. More sensitive all-sky CMB polarization data, such as those expected from the future LiteBIRD experiment, are needed to reach a more robust conclusion on the possible existence of deviations from statistical isotropy in the form of a hemispherical power asymmetry.
Axion-photon conversion in 3D media and astrophysical plasmas
Authors: McDonald J.I. , Garbrecht B. , Millington P.
Published: December 2023

With axions now a primary candidate for dark matter, understanding their indirect astrophysical signatures is of paramount importance. Key to this is the production of photons from axions in magnetised astrophysical plasmas. While simple formulae for axion-photon mixing in 1D have been sketched several decades ago, there has recently been renewed interest in robust calculations for this process in arbitrary 3D plasmas. These calculations are vital for understanding, amongst other things, the radio production from axion dark matter conversion in neutron stars, which may lead to indirect axion dark matter detection with current telescopes or future searches, e.g., by the SKA. In this paper, we derive the relevant transport equations in magnetised plasmas. These equations describe both the production and propagation of photons in an arbitrary 3D medium due to the resonant conversion of axions into photons. They also fully incorporate the refraction of photons, and we find no evidence for a conjectured phenomenon of dephasing. Our result is free of divergences which plagued previous calculations, and our kinetic theory description provides a direct link between ray tracing and the production mechanism. These results mark an important step toward solving one of the major open questions concerning indirect searches of axions in recent years, namely how to compute the photon production rate from axions in arbitrary 3D plasmas.
Entropic property of randomized QAOA circuits
Authors: Chernyavskiy A Yu , Bantysh B I , Bogdanov Yu I
Published: December 2023

Quantum approximate optimization algorithm (QAOA) aims to solve discrete optimization problems by sampling bitstrings using a parameterized quantum circuit. The circuit parameters (angles) are optimized in the way that minimizes the cost Hamiltonian expectation value. Recently, general statistical properties of QAOA output probability distributions have begun to be studied. In contrast to the conventional approach, we analyse QAOA circuits with random angles. We provide analytical equations for probabilities and the numerical evidence that for unweighted Max-Cut problems on connected graphs such sampling always gives higher entropy of energy distribution than uniform random sampling of bitstrings. We also analyse the probability to obtain the global optima, which appears to be higher on average than for random sampling.
Phonon resonance modulation in weak van der Waals heterostructures: Controlling thermal transport in graphene–silicon nanoparticle systems
Authors: Li 李 Yi 毅 , Liu 刘 Yinong 一浓 , Hu 胡 Shiqian 世谦
Published: December 2023

The drive for efficient thermal management has intensified with the miniaturization of electronic devices. This study explores the modulation of phonon transport within graphene by introducing silicon nanoparticles influenced by van der Waals forces. Our approach involves the application of non-equilibrium molecular dynamics to assess thermal conductivity while varying the interaction strength, leading to a noteworthy reduction in thermal conductivity. Furthermore, we observe a distinct attenuation in length-dependent behavior within the graphene–nanoparticles system. Our exploration combines wave packet simulations with phonon transmission calculations, aligning with a comprehensive analysis of the phonon transport regime to unveil the underlying physical mechanisms at play. Lastly, we conduct transient molecular dynamics simulations to investigate interfacial thermal conductance between the nanoparticles and the graphene, revealing an enhanced thermal boundary conductance. This research not only contributes to our understanding of phonon transport but also opens a new degree of freedom for utilizing van der Waals nanoparticle-induced resonance, offering promising avenues for the modulation of thermal properties in advanced materials and enhancing their performance in various technological applications.