bluuebunny/crossref_metadata_2025 huggingface dataset:
Ensuring sustainable development of agriculture: legal, managerial, digital approaches
Authors: Petrova Galina , Stupakov Valery
Published: April 2023

The article discusses modern legal, managerial, digital approaches to ensuring the sustainable development of agriculture. The norms and standards of agricultural risk insurance, budget lending, organic agribusiness modeling and food safety developed by international institutions are evaluated. Methods of comparative, legal, informational analysis and scientific generalization of theoretical knowledge revealed organizational problems of budgeting and quality control of agricultural products, preventing food losses, and combating falsification of food products. It was noted that legal measures and management standards optimize agribusiness segments, reduce the number of intermediaries, and improve the trust of suppliers and consumers through direct links. The digitalization of agriculture contributes to the transparency of data exchange while reducing information imbalances and transaction costs for participants in agricultural markets. The connection of standards and norms of legal regulation of sustainable development of agriculture with food security in the EU and the EAEU is shown. The conclusions are indicated by the positive prospects for digital management of agribusiness subsidies and digital budgeting as the level increases in the EU and the EAEU. Unlike the EU, the EAEU is building a common space for organic and digital agriculture on the principles of Eurasian integration and cooperation.
Assessment of agricultural production in Russia in the context of global food security
Authors: Alekseeva Natalia , Mironova Zinaida , Aleksandrova Elena , Istomina Larisa , Mironova Marina
Published: April 2023

The world’s economies are focused on sustainable development and food security. One of the main components of the food security system of the country - agricultural production - is highlighted. The study aims to identify the problems and prospects for the development of food security. The objectives of the study are related to the justification of the system of indicators (criteria) to assess the level of food security of countries, the choice of the list of countries for comparative analysis, conducting economic and statistical analysis, formulating directions to improve food security management. The system of indicators to assess the level of food security in the countries based on the assessment of average annual indices of production and consumption of products per capita and per arable land or livestock, poultry. An assessment of food security in terms of agricultural development indicators was conducted for the years 2010-2018. The scientific novelty of the research consists in the development of a methodology for assessing food security indicators, assessment of progressive and negative changes in the level of food security, formulation of conclusions to improve food security in Russia. The practical significance of the study lies in the possibility of developing a more efficient state agricultural policy.
Development of chitosan nanoparticles for anticancer drug delivery systems
Authors: Fatkullina Larisa , Shmelev Mikhail , Silantev Vladimir , Kumeiko Vadim
Published: April 2023

Chitosan is a natural polymer that is often used in nanotechnology because it has such useful properties as biodegradability and biocompatibility. Chitosan has many benefits, but they are outweighed by drawbacks such insolubility, aggregation at physiological pH, and insufficient cargo release in the cytosol. In order to obtain chitosan nanoparticles that can be used as drug delivery systems, we optimized the synthesis technology by selecting MES buffer pH 6.3 and using a BSA coating step to reduce nanoparticle aggregation. Deposition of the chemotherapeutic agent etoposide in chitosan nanoparticles has been proven and confirmed by IR spectra, although future experiments are needed to tune conditions for stronger interactions. The chitosan nanoparticles that we have obtained can become suitable nanomaterials for biomedical applications as promising carriers for drug delivery.
Formation of composite coatings: morphology and composition studies
Authors: Piatkova Mariia , Pleshkova Arina , Mashtalyar Dmitry , Imshinetskiy Igor , Nadaraia Konstantine , Sinebryukhov Sergey , Gnedenkov Sergey
Published: April 2023

In this work, composite fluoropolymer-containing coatings were obtained on samples of AMg3 aluminium alloy, MA8 magnesium alloy, and VT1-0 commercially pure titanium treated by plasma electrolytic oxidation (PEO). Superdispersed polytetrafluoroethylene (SPTFE) and a solution of tetrafluoroethylene (TFE) telomers in acetone were applied onto preliminarily formed PEO layers by the spray-coating method. The obtained coatings contained a large amount of crystalline polytetrafluoroethylene embedded in the outer porous layer of the PEO coating and did not have visible defects, which indirectly indicates high protective properties.
Investigation of physical and mechanical properties of mixed gypsum material for slip casting molds
Authors: Severenkova Valeriia , Kharitonov Dmitriy , Anashkina Antonina
Published: April 2023

The issues of improvement and optimization of the properties and structure of porous molds used in the ceramic industry are still relevant. In this work, plaster materials based on the mix of α- and β-calcium sulfate hemihydrate (α-CaSO4·0.5H2O, β-CaSO4·0.5H2O) were received and their properties were studied. Based on the test results of the strength characteristics, water adsorption and kinetics of formation process, the optimum composition of gypsum binder was proposed for application in technical ceramics production.
The issue of residual stresses in additive technologies
Authors: Tabanykhova Marina , Stolyarov Nikolay , Nagel Arthur
Published: April 2023

The paper considers the issue of residual stresses in 3D-printed plastic models. Most additive technologies create residual stresses in products. Residual stresses occur in the printed material due to its expansion when heated and contraction when cooled. Residual stresses and their intensity depend on the printing technology and technique. The paper discusses the impact of printing techniques and various printing nozzle diameters and model shapes (rectangular, circular) on the occurrence of residual stresses in specimens. As part of the study, in transparent models, residual stresses were detected using a PPU-7 polarization-projection unit. Two series of six specimens each have been printed. The first and second series models had the shape of a parallelepiped and a disk, respectively. The frequency-division multiplexing technology was chosen. In the study, the models were manufactured from a polyethylene terephthalate-glycol plastic filament. This material has a high optical sensitivity. Nozzles of two diameters (0.4 and 1 mm) were used to print specimens. Shell-less and singleand double-shell specimens were printed. The dependence of residual stresses on the specimen shape, the printing nozzle diameter, and the model shell thickness has been estimated. The study is focused on finding a technique for printing models from plastic filament, completely free of residual stresses in the specimen material. This is dictated by the photoelasticity requirements for piezo-optical materials, including some transparent plastics used in 3D printing.
Effect of carbon nanotubes incorporation on the properties of the PEO coatings formed on MgMn-Ce alloy
Authors: Imshinetskiy Igor , Kashepa Victoria , Nadaraia Konstantine , Mashtalyar Dmitry , Sinebryukhov Sergey , Gnedenkov Sergey
Published: April 2023

The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing multi-walled carbon nanotubes in concentrations of 2, 4 and 6 g/l have been investigated. It was found that the introduction of multi-walled carbon nanotubes leads to an increase in the adhesive strength, microhardness and Young’s modulus of the obtained layers.
Photocatalytic reduction of CO2 over TiO2 nanowires catalyst
Authors: Tarasov Andrey , Dubkov Sergey , Evgeny Vigdrovich , Maria Fedyanina , Roman Ryazanov , Anna Sirotina , Gromov Dmitriy
Published: April 2023

TiO2 is one of the most common photocatalysts at the moment. One-dimensional TiO2, which has a high specific surface area, is of particular interest. The properties of such nanowires will largely depend on the phase composition, which affects the width of the optical band gap. This paper presents the results of a study of the photocatalytic activity of TiO2 nanowires depending on the phase composition using the reduction of CO2 to methane and methanol as an example. The formation of TiO2 nanowires was carried out using a hydrothermal synthesis method from a commercial TiO2 powder. After synthesis, the nanowires were thermally treated in air to obtain nanowires with different phase compositions. The morphology and phase composition of TiO2 nanowires were studied. The resulting nanowires had a size of about 8 μm and a diameter of about 330 nm.
Ultrasonic testing via three-dimensional post-processing of non-uniform matrix phased array data
Authors: Dolmatov Dmitry
Published: April 2023

The tomography based on post-processing of phased array signals is of great potential for ultrasonic testing to accurately size the detected flaws. The use of matrix phased arrays in ultrasound tomography can provide three-dimensional data both at one measuring position and during scanning. However, application of these transducers implies processing of a large amount of data, which affects the data processing time. In this study, the post-processing frequency-domain algorithm based on the application of non-uniform fast Fourier transform was experimentally verified. This algorithm is allowed to restore correct results when approaches of optimised set of signals acquisition (sparse and non-uniform phased arrays) are applied. The experimental verification showed that the developed algorithm yields high-resolution results with a high signal-to-noise ratio.
„Wind of change“
Authors: Kehl Sven
Published: April 2023

Liebe Leserinnen und Leser,

spüren Sie auch diesen Wind? Es gab ihn schon mal. Das Lied „Wind of
Change" ist ein Song der deutschen Rockband Scorpions und handelt von der
politischen und gesellschaftlichen Veränderung, die Anfang der 1990er-Jahre
in Europa stattfand, insbesondere im Zusammenhang mit dem Fall der Berliner Mauer
und dem Ende des Kalten Krieges. Das Lied reflektiert die Hoffnungen und
Träume der Menschen in diesem historischen Moment des Wandels und feiert das
Ende einer Ära der Konfrontation und des Misstrauens zwischen Ost und West.
Es ist eine Hymne an die Freiheit und die Überwindung von Grenzen, die
sowohl politisch als auch persönlich sein können.
Einfluss eines vierwöchigen achtsamkeitsbasierten Trainings
auf die Lebenszufriedenheit
Authors: Stang Philipp , Rico-Dresel Daniela
Published: April 2023

Aufbauend auf der Studie von Demarzo und Kollegen (2017), in welcher eine
vierwöchige achtsamkeitsbasierte Intervention eine ähnliche
Wirksamkeit wie das achtwöchige Mindfulness Based Stress Reducation
Training aufzeigte, wurde das Training der vorliegenden Arbeit gestaltet. Die
insgesamt 120 Proband*innen unterteilten sich in eine Experimentalgruppe
(n=80) und eine Kontrollgruppe (n=40) welche zu zwei
Messzeitpunkten Fragebögen über deren
Achtsamkeitsfähigkeit (Mindful Attention and Awareness Scale (MAAS)) und
Lebenszufriedenheit (Fragebogen zur allgemeinen Lebenszufriedenheit (FLZ),
Kurzskala Lebenszufriedenheit-1 (L-1)) ausfüllten. Es zeigte sich, dass
die Achtsamkeitsfähigkeit der Experimentalgruppe nach dem Training
anstieg und sich signifikant (p=0,05) sowohl vom ersten Messzeitpunkt,
als auch von der Kontrollgruppe zu beiden Messzeitpunkten unterschied. Ebenso
verhielt es sich mit der Lebenszufriedenheit, die mit einer Multi-Item-Skala
gemessen wurde.
Non-drainage Offers Faster Proprioceptive and Functional Recovery, and More Clinical Benefits for Patients following Primary Total Knee Arthroplasty Compared to Drainage
Authors: Unver Bayram , Eymir Musa , Karatosun Vasfi
Published: April 2023

Background Although a non-drainage procedure following total knee arthroplasty (TKA) is becoming more acceptable in enhanced recovery after surgery, postoperative drainage is still commonly used in TKA surgeries. This study aimed to compare the non-drainage to the drainage during the early postoperative stage regarding proprioceptive and functional recovery, and postoperative outcomes of TKA patients.

Material and Methods A prospective, single-blind, randomized, controlled trial was carried out on 91 TKA patients, who were randomly allocated into the non-drainage group (NDG) or the drainage group (DG). Patients were evaluated regarding knee proprioception, functional outcomes, pain intensity, range of motion, knee circumference, and anesthetic consumption. Outcomes were assessed at the time of charge, at postoperative 7th day, and at postoperative 3rd month.

Results There were no differences between groups at baseline (p > 0.05). During the inpatient period, the NDG experienced superior pain relief (p < 0.05), had a higher Hospital for Special Surgery knee score (p = 0.001), demanded lower assistance from a sitting position to a standing position (p = 0.001) and walking for 4.5 m (p = 0.034), and performed the Timed Up and Go test in a shorter duration (p = 0.016) compared to the DG. The NDG gained the actively straight leg raise earlier (p = 0.009), needed lower anesthetic consumption (p < 0.05), and showed improved proprioception (p < 0.05) compared to the DG during the inpatient period.

Conclusions Our findings support that a non-drainage procedure would be a better option to provide a faster proprioceptive and functional recovery, and beneficial results for patients following TKA. Therefore, the non-drainage procedure should be the first choice in TKA surgery rather than drainage.
Media portrayal of old age and its effects on attitudes in older people: findings from a series of studies
Authors: Wangler Julian , Jansky Michael
Published: April 2023

Mass media portrayal of old age plays a great role in social perceptions of aging. However, there are hardly any empirical findings on the effects on recipients or to what extent this can change attitudes, especially amongst older people. Three types of media portrayals of old age in German news magazines were determined and used as stimulus material. In 2020, 910 participants (from 60 years) were confronted with different age frames in the course of a quasi-experimental survey. In order to substantiate the results, in 2022, 36 focused interviews were conducted with older people each of whom was presented with an age frame. This article links the central findings of both studies, with a focus on the qualitative study. The survey results showed that presenting a negative age frame led to an improvement in the self-image of old age whereas the public image of old age deteriorated significantly. After presenting a positive frame, the public image improved greatly while the self-image decreased. The interviews confirm these results. Type of reaction upon reception of the negative age frame varied between approval and clear signs of consternation. However, interviewees did not relate with the older people portrayed with personal aging often felt to be at odds with the portrayal of age shown. The positive frame was first received with pleasure and curiosity. Even so, interviewees became unsettled about how ‘modern’ aging is portrayed, some of them showing insecurity that they could not fulfil the characteristics and requirements of ‘modern’ aging. Media portrayal of age seems not to have the effects on older people as might be expected. Negative effects appear such as media portrayal making older recipients aware of their own age by presenting age in an exaggeratedly positive light in the “best agers” frame. In view of these results, the theory of social comparison processes may be used by which the media provides recipients with standards of comparison.
Bottom-up synthesis of mesoscale nanomeshes of graphene nanoribbons on germanium
Authors: Saraswat Vivek , Way Austin J. , Zheng Xiaoqi , Jacobberger Robert M. , Manzo Sebastian , Tiwale Nikhil , Dwyer Jonathan H. , Kawasaki Jason K. , Nam Chang-Yong , Gopalan Padma , Arnold Michael S.
Published: April 2023

The synthesis of functional graphene nanostructures on Ge(001) provides an attractive route toward integrating graphene-based electronic devices onto complementary metal oxide semiconductor-compatible platforms. In this study, we leverage the phenomenon of the anisotropic growth of graphene nanoribbons from rationally placed graphene nanoseeds and their rotational self-alignment during chemical vapor deposition to synthesize mesoscale graphene nanomeshes over areas spanning several hundred square micrometers. Lithographically patterned nanoseeds are defined on a Ge(001) surface at pitches ranging from 50 to 100 nm, which serve as starting sites for subsequent nanoribbon growth. Rotational self-alignment of the nanoseeds followed by anisotropic growth kinetics causes the resulting nanoribbons to be oriented along each of the equivalent, orthogonal Ge⟨110⟩ directions with equal probability. As the nanoribbons grow, they fuse, creating a continuous nanomesh. In contrast to nanomesh synthesis via top-down approaches, this technique yields nanomeshes with atomically faceted edges and covalently bonded junctions, which are important for maximizing charge transport properties. Additionally, we simulate the electrical characteristics of nanomeshes synthesized from different initial nanoseed-sizes, size-polydispersities, pitches, and device channel lengths to identify a parameter-space for acceptable on/off ratios and on-conductance in semiconductor electronics. The simulations show that decreasing seed diameter and pitch are critical to increasing nanomesh on/off ratio and on-conductance, respectively. With further refinements in lithography, nanomeshes obtained via seeded synthesis and anisotropic growth are likely to have superior electronic properties with tremendous potential in a multitude of applications, such as radio frequency communications, sensing, thin-film electronics, and plasmonics.
Diffusion of Sn donors in β-Ga2O3
Authors: Frodason Ymir K. , Krzyzaniak Patryk P. , Vines Lasse , Varley Joel B. , Van de Walle Chris G. , Johansen Klaus Magnus H.
Published: April 2023

Diffusion of the n-type dopant Sn in β-Ga2O3 is studied using secondary-ion mass spectrometry combined with hybrid functional calculations. The diffusion of Sn from a Sn-doped bulk substrate with surface orientation (001) into an epitaxial layer is observed after heat treatments in the temperature range of 1050–1250 °C. Calculated formation energies of Sn-related and intrinsic defects show that the migration of Sn is mediated by Ga vacancies (VGa) through the formation and dissociation of intermittent mobile VGaSnGa complexes. The evolution of the Sn concentration vs depth profiles after heat treatments can be well described by a reaction–diffusion model. Using model parameters guided by the hybrid functional calculations, we extract a VGaSnGa complex migration barrier of 3.0 ± 0.4 eV with a diffusion coefficient of 2 × 10−1 cm2/s. The extracted migration barrier is consistent with our theoretical predictions using the nudged elastic band method, which shows migration barriers of 3.42, 3.15, and 3.37 eV for the [100], [010], and [001] directions, respectively.
Macroscopic shaping of coordination polymer via crystal–glass phase transformation as monolithic catalyst for efficient catalyst recovery
Authors: Tiyawarakul Thanakorn , Imyen Thidarat , Kongpatpanich Kanokwan , Watcharatpong Teerat , Horike Satoshi
Published: April 2023

To circumvent the difficult processability and recovery of catalytic materials in powder form, we herein report macroscopic shaping of 1D coordination polymer consisting of zinc ions, orthophosphate, and benzimidazole, namely ZnPBIm, motivated by the crystal–glass phase transformation. Glassy ZnPBIm monoliths with different shapes and sizes were prepared via a melt-quench process without using the secondary component. As a heterogeneous acid catalyst, the glassy ZnPBIm monoliths contribute to the esterification of levulinic acid with ethanol at 100 °C with recyclability for at least three consecutive cycles, and over 90% of catalyst mass was recovered. The macroscopic shape of the monoliths was retained after 24 h of reaction. Surface crystallization of glassy ZnPBIm was induced by the presence of water during esterification, and the glass domain serves as a macroscopic support for the crystallized domain.
Estimating threshold stresses using parametric equations for creep: Application to low-alloy steels
Authors: Evans M.
Published: April 2023

The power law model produces both temperature varying and unreliable estimates for its parameters. Threshold stresses have been suggested as a solution. The power law and Wilshire models are modified to include this stress and estimation and error decomposition methods applied to assess its importance in representing failure times. A statistically significant and temperature-dependent threshold stress was identified in two low-alloy steels. This threshold stress was closer to the operating stress in the Wilshire model. The inclusion of this stress reduced interpolation errors, but this improvement was greater in the Wilshire model. The Wilshire model increased the random component of these errors at all temperatures in one material, but only at some temperatures for the other.
Circulating markers of intestinal barrier injury and inflammation following exertion in hypobaric hypoxia
Authors: McKenna Zachary J. , Bellovary Bryanne N. , Ducharme Jeremy B. , Deyhle Michael R. , Wells Andrew D. , Fennel Zachary J. , Specht Jonathan W. , Houck Jonathan M. , Mayschak Trevor J. , Mermier Christine M.
Published: April 2023

Hypoxia induced intestinal barrier injury, microbial translocation, and local/systemic inflammation may contribute to high‐altitude associated gastrointestinal complications or symptoms of acute mountain sickness (AMS). Therefore, we tested the hypothesis that six‐hours of hypobaric hypoxia increases circulating markers of intestinal barrier injury and inflammation. A secondary aim was to determine if the changes in these markers were different between those with and without AMS. Thirteen participants were exposed to six hours of hypobaric hypoxia, simulating an altitude of 4572 m. Participants completed two 30‐minute bouts of exercise during the early hours of hypoxic exposure to mimic typical activity required by those at high altitude. Pre‐ and post‐exposure blood samples were assessed for circulating markers of intestinal barrier injury and inflammation. Data below are presented as mean ± standard deviation or median [interquartile range]. Intestinal fatty acid binding protein (Δ251 [103–410] pg•mL−1; p = 0.002, d = 0.32), lipopolysaccharide binding protein (Δ2 ± 2.4 μg•mL−1; p = 0.011; d = 0.48), tumor necrosis factor‐α (Δ10.2 [3–42.2] pg•mL−1; p = 0.005; d = 0.25), interleukin‐1β (Δ1.5 [0–6.7] pg•mL−1 p = 0.042; d = 0.18), and interleukin‐1 receptor agonist (Δ3.4 [0.4–5.2] pg•mL−1p = 0.002; d = 0.23) increased from pre‐ to post‐hypoxia. Six of the 13 participants developed AMS; however, the pre‐ to post‐hypoxia changes for each marker were not different between those with and without AMS (p > 0.05 for all indices). These data provide evidence that high altitude exposures can lead to intestinal barrier injury, which may be an important consideration for mountaineers, military personnel, wildland firefighters, and athletes who travel to high altitudes to perform physical work or exercise.
Predicted the structural diversity and electronic properties of Pt−N compounds under high pressure
Authors: Feng Quanchao , Xiao Xun , Dai Wei , Sun Weiguo , Ding Kewei , Lu Cheng
Published: April 2023

The nitrogen-rich transition metal nitrides have attracted considerable attention due to their potential application as high energy density materials. Here, a systematic theoretical study of PtN
x
compounds has been performed by combining first-principles calculations and particle swarm-optimized structure search method at high pressure. The results indicate that several unconventional stoichiometries of PtN2, PtN4, PtN5, and Pt3N4 compounds are stabilized at moderate pressure of 50 GPa. Moreover, some of these structures are dynamically stable even when the pressure release to ambient pressure. The P

1
ˉ

phase of PtN4 and the P

1
ˉ

phase of PtN5 can release about 1.23 kJ g−1 and 1.71 kJ g−1, respectively, upon the decomposition into elemental Pt and N2. The electronic structure analysis shows that all crystal structures are indirect band gap semiconductors, except for the metallic Pt3N4 with Pc phase, and the metallic Pt3N4 is a superconductor with estimated critical temperature T
c values of 3.6 K at 50 GPa. These findings not only enrich the understanding of transition metal platinum nitrides, but also provide valuable insights for the experimental exploration of multifunctional polynitrogen compounds.
Electronic properties and passivation mechanism of AlGaN/GaN heterojunction with vacancies: a DFT study
Authors: Li Leilei , He Shanshan , Tu Yuhang , Guo Bingrui , Liu Fei , He Shan , Li Qiuhong , Guo Donghui
Published: April 2023

A significant issue for GaN-based high-electron-mobility transistors (HEMTs) in high power devices is the material defect, particularly the defect states generated by the defects, which has a negative impact on the device carrier concentration and carrier transport. Based on density functional theory (DFT), we investigate the microscopic properties of different type point vacancies in the AlGaN/GaN heterojunction. It is found that N vacancy introduces defect states near the conduction band minimum (CBM) of the GaN layer and AlGaN/GaN interface. Ga and Al vacancies introduce defect states near the valence band maximum (VBM) in bulk and interface of AlGaN/GaN heterojunction. Moreover, Al vacancy is more likely to be an effective candidate for acceptor defect than Ga vacancy. We further study several AlGaN/GaN interface passivation schemes by introducing F, V group element P, and III group element B at the AlGaN/GaN heterojunction interface to analyze the passivation mechanism. According to the results of the passivation models, B passivation of Ga and Al vacancies is an effective method to completely remove the defect states from Ga and Al vacancy defects. Combining the III and V groups elements into the passivated process may be effective in achieving high-quality AlGaN/GaN heterojunction interface for the future GaN-based HEMTs fabrication.
The two-turn quantum games with continuous-variable strategies
Authors: Wang Nengfa , Yang Zhe
Published: April 2023

This paper investigates the two-turn quantum games with continuous-variable strategies by adopting the Li-Du-Massar method and Frackiewicz quantum scheme. We find that the entanglement level of Li-Du-Massar quantum scheme has a negative effect on the quantum equilibrium payoffs, and the entanglement level of Frackiewicz quantum scheme has a positive effect on the quantum equilibrium payoffs. Our analysis allows us to add a new look at the quantum games.
He adsorption and sensing properties of graphene nanoflakes doped with Mo and Nb
Authors: Monadi Mohammad Mahdi , Rouhani Morteza , Aliabad Javad Mokhtari
Published: April 2023

DFT calculations have been performed to study the He adsorption on the surface of Mo-doped graphene and Nb-doped graphene nanoflakes in order to evaluate the capability of studied doped graphene sheets as effective gas sensor materials. The ωB97XD (including dispersion)/6-311++G(d,p) (LanL2DZ for Mo and Nb) level of theory were utilized in this investigation. The HOMO-LUMO gap (Eg) of the Mo-doped and Nb-doped graphene structures decreased upon He adsorption on both sheets (−37.77% and −8.33%, respectively). Therefore, the electrical conductivity of both surfaces have increased. However, alteration of the Eg value in Mo-doped graphene is very higher than that of Nb-doped graphene. So, the Mo-doped graphene is more sensitive to He molecule in comparison with Nb-doped graphene and it could be used as a gas sensor material to detect He gas. Variety analyses such as natural bond orbital (NBO), density of states (DOS), electron density distribution (ED), electron localization function (ELF) and non-covalent interaction-reduced density gradient (NCI-RDG) have been carried-out in order to better evaluate the He adsorption nature on the investigated surfaces.
Quantum cosmology, eternal inflation, and swampland conjectures
Authors: Fanaras Georgios , Vilenkin Alexander
Published: April 2023

In light of the recent swampland conjectures, we explore quantum cosmology and eternal inflation beyond the slow roll regime.
We consider a model of a closed universe with a scalar field ϕ in the framework of tunneling approach to quantum cosmology. The scalar field potential is assumed to have a maximum at ϕ = 0 and can be approximated in its vicinity as V(ϕ)≈ 3H
2 - 1/2m
2
ϕ
2. Using the instanton method, we find that for m < 2H the dominant nucleation channel for the universe is tunneling to a homogeneous, spherical de Sitter space. For larger values of m/H, the most probable tunneling is to an inhomogeneous closed universe with a domain wall wrapped around its equator. We determine the quantum state of the field ϕ in the nucleated universe by solving the Wheeler-DeWitt equation with tunneling boundary conditions. Our results agree with earlier work which assumed a slow-roll regime m ≪ H. We finally show that spherical universes nucleating with m < 2H undergo stochastic eternal inflation with inflating regions forming a fractal of dimension d > 2. For larger values of m the field ϕ is unstable with respect to formation of domain walls and cannot be described by a perturbative stochastic approach.
Anomalous Josephson effect between d-wave superconductors through a two-dimensional electron gas with both Rashba spin–orbit coupling and Zeeman splitting
Authors: Du Bin-Hao , Yang Mou , Hu Liang-Bin
Published: April 2023

Based on the Bogoliubov–de Gennes equation and the extended McMillan’s Green’s function formalism, we study theoretically the Josephson effect between two d-wave superconductors bridged by a ballistic two-dimensional electron gas with both Rashba spin–orbit coupling and Zeeman splitting. We show that due to the interplay of Rashba spin–orbit coupling and Zeeman splitting and d-wave pairing, the current–phase relation in such a heterostructure may exhibit a series of novel features and can change significantly as some relevant parameters are tuned. In particular, anomalous Josephson current may occur at zero phase bias under various different situations if both time reversal symmetry and inversion symmetry of the system are simultaneously broken, which can be realized by tuning some relevant parameters of the system, including the relative orientations and the strengths of the Zeeman field and the spin–orbit field in the bridge region, the relative orientations of the a axes in two superconductor leads, or the relative orientations between the Zeeman field in the bridge region and the a axes in the superconductor leads. We show that both the magnitude and the direction of the anomalous Josephson current may depend sensitively on these relevant parameters.
Enhancement of the group delay in quadratic coupling optomechanical systems subjected to an external force
Authors: Talla Mbé Jimmi Hervé , Tiofack Demanou Ulrich Chancelin , Kenfack-Sadem Christian , Tchoffo Martin
Published: April 2023

We theoretically study the effect of the quadratic coupling strength on optomechanical systems subjected to a continuous external force. Quadratic coupling strength originates from strong coupling between the optical and the mechanical degrees of freedom. We show that the quadratic coupling strength reduces the amplitude of the dispersion spectra at the resonance in both blue- and red-sideband regimes. However, it increases (decreases) the amplitude of the absorption spectrum in the blue- (red-)sideband regime. Furthermore, in both sideband regimes, the effective detuning between the pump and the cavity deviates with the quadratic coupling strength. Thereby, appropriate selection of the quadratic coupling strength results in an important magnification (in absolute value) of the group delay for both slow and fast light exiting from the optomechanical cavity.
Layered double hydroxides as electrode materials for flexible energy storage devices
Authors: Lin Qifeng , Wang Lili
Published: April 2023

To prevent and mitigate environmental degradation, high-performance and cost-effective electrochemical flexible energy storage systems need to be urgently developed. This demand has led to an increase in research on electrode materials for high-capacity flexible supercapacitors and secondary batteries, which have greatly aided the development of contemporary digital communications and electric vehicles. The use of layered double hydroxides (LDHs) as electrode materials has shown productive results over the last decade, owing to their easy production, versatile composition, low cost, and excellent physicochemical features. This review highlights the distinctive 2D sheet-like structures and electrochemical characteristics of LDH materials, as well as current developments in their fabrication strategies for expanding the application scope of LDHs as electrode materials for flexible supercapacitors and alkali metal (Li, Na, K) ion batteries.
Narrow-bandwidth, extreme ultraviolet, spontaneous light-imaging technique for laser-driven magnetic reconnection studies
Authors: An H.H. , Xiong J. , Fang Z.H. , Wang W. , Sun J.R. , Wang C.
Published: April 2023

Laser-driven magnetic reconnection (LDMR) is an important research topic in the field of high-energy-density physics, such as laboratory astrophysics. In this study, the narrow bandwidth spontaneous light imaging (SLI) technique at the extreme ultraviolet (EUV) band is introduced to detect magnetic reconnection and the jets produced by LDMR. The EUV-based SLI technique will provide reference values for the verification of the results obtained with traditional methods.
High spatial resolution direct conversion amorphous selenium X-ray detectors with monolithically integrated CMOS readout
Authors: Han Z. , Mukherjee A. , Albert A. , Rumaiz A.K. , Harding I. , Tate M.W. , Gruner S.M. , Thom-Levy J. , Kuczewski A.J. , Siddons D.P. , Carini G.A. , Stavro J. , Léveillé S. , Vasileska D. , Zhao W. , Goldan A.
Published: April 2023

Recent progress in the field of micron-scale spatial
resolution direct conversion X-ray detectors for high-energy synchrotron light sources serve applications ranging from nondestructive and noninvasive microscopy techniques which provide insight into the structure and morphology of crystals, to medical diagnostic measurement devices. Amorphous selenium (a-Se) as a wide-bandgap thermally evaporated photoconductor exhibits ultra-low thermal generation rates for dark carriers and has been extensively used in X-ray medical imaging. Being an amorphous material, it can further be deposited over large areas at room temperatures and at substantially lower costs as compared to crystalline semiconductors. To address the demands for a high-energy and high spatial resolution X-ray detector for synchrotron light source applications, we have thermally evaporated a-Se on a Mixed-Mode Pixel Array Detector (MM-PAD) Application Specific Integrated Circuit (ASIC). The ASIC format consists of 128 × 128 square pixels each 150 μm on a side. A 200 μm a-Se layer was directly deposited on the ASIC followed by a metal top electrode. The completed detector assembly was tested with 45 kV Ag and 23 kV Cu X-ray tube sources. The detector fabrication, performances, Modulation Transfer Function (MTF) measurements, and simulations are reported.
A biopolymeric mesh enriched with PLGA microparticles loaded with AT101 for localized glioblastoma treatment
Authors: Hellmold Dana , Arnaldi Pietro , Synowitz Michael , Held-Feindt Janka , Akbari Mohsen
Published: April 2023

Current treatment strategies for glioblastoma (GBM) including surgical resection and adjuvant radio/chemotherapy result in a limited progression-free survival time of patients due to rapidly occurring tumor recurrences. The urgent need for more effective treatments has led to the development of different approaches for localized drug delivery systems (DDSs) offering the advantages of reduced systemic side effects. A promising candidate for the treatment of GBMs is AT101, the R-(-)-enantiomer of gossypol due to its ability to induce apoptosis or trigger autophagic cell death in tumor cells. Here, we present an alginate-based drug-releasing mesh ladened with AT101-loaded PLGA microspheres (AT101-GlioMesh). The AT101-loaded PLGA microspheres were fabricated using an oil-in-water emulsion solvent evaporation method obtaining a high encapsulation efficiency. The drug-loaded microspheres enabled the release of AT101 over several days at the tumor site. The cytotoxic effect of the AT101-loaded mesh was evaluated using two different GBM cell lines. Strikingly, encapsulation of AT101 in PLGA-microparticles and subsequent embedding in GlioMesh resulted in a sustained delivery and more efficient cytotoxic effect of AT101 on both GBM cell lines. Thus, such a DDS holds promise for GBM therapy likely by preventing the development of tumor recurrences.
Joint distribution of two local times for diffusion processes with the application to the construction of various conditioned processes
Authors: Mazzolo Alain , Monthus Cécile
Published: April 2023

For a diffusion processX(t) of driftμ(x)and of diffusion coefficientD=1/2, we study the joint distribution of the two local timesA(t)=∫0tdτδ(X(τ))andB(t)=∫0tdτδ(X(τ)−L)at positionsx = 0 andx = L, as well as the simpler statistics of their sumΣ(t)=A(t)+B(t). Their asymptotic statistics for large timet→+∞involves two very different cases: (i) when the diffusion processX(t) is transient, the two local times[A(t);B(t)]remain finite random variables[A∗(∞),B∗(∞)]and we analyze their limiting joint distribution; (ii) when the diffusion processX(t) is recurrent, we describe the large deviations properties of the two intensive local timesa=A(t)tandb=B(t)tand of their intensive sumσ=Σ(t)t=a+b. These properties are then used to construct various conditioned processes[X∗(t),A∗(t),B∗(t)]satisfying certain constraints involving the two local times, thereby generalizing our previous work (Mazzolo and Monthus 2022J. Stat. Mech.103207) concerning the conditioning with respect to a single local timeA(t). In particular for the infinite time horizonT→+∞, we consider the conditioning towards the finite asymptotic values[A∗(∞),B∗(∞)]orΣ∗(∞), as well as the conditioning towards the intensive values[a∗,b∗]orσ∗, that can be compared with the appropriate ‘canonical conditioning’ based on the generating function of the local times in the regime of large deviations. This general construction is then applied to the simplest case where the unconditioned diffusion is the Brownian motion of uniform driftµ.
Adjusting phase-covariant qubit channel performance with non-unitality
Authors: Siudzińska Katarzyna , Studziński Michał
Published: April 2023

We analyze quantum communication properties of phase-covariant channels depending on their degree of non-unitality. In particular, we derive analytical formulas for the minimal and maximal channel fidelity on pure states and maximal output purity. Next, we introduce a measure of non-unitality and show how to manipulate between unital and maximally non-unital maps by considering classical mixtures of quantum channels. Finally, we prove that maximal fidelity and maximal output purity increase with non-unitality and present several examples. Interestingly, non-unitality can also prolong quantum entanglement and lead to its rebirth.
Visualizing dynamic three-dimensional changes of human reticular dermal collagen under mechanical strain
Authors: van Haasterecht L , Zhou M , Ma Y , Bartolini L , Van Mourik F , Van Zuijlen P P M , Groot M L
Published: April 2023

In clinical practice, plastic surgeons are often faced with large skin defects that are difficult to close primarily. Management of large skin wounds e.g. burns or traumatic lacerations requires knowledge of skin biomechanic properties. Research into skin microstructural adaptation to mechanical deformation has only been performed using static regimes due to technical limitations. Here, we combine uniaxial stretch tests with fast second harmonic generation imaging and we apply this for the first time to investigate dynamic collagen rearrangement in reticular human dermis. Ex vivo human skin from the abdomen and upper thigh was simultaneously uniaxially stretched while either periodically visualizing 3D reorganization, or visualizing 2D changes in real time. We determined collagen alignment via orientation indices and found pronounced variability across samples. Comparing mean orientation indices at the different stages of the stress strain curves (toe, heel, linear) showed a significant increase in collagen alignment during the linear part of the mechanical response. We conclude that fast SHG imaging during uni-axial extension is a promising research tool for future studies on skin biomechanic properties.
Chemical and physical studies of metallic alloy-based old Indian coins with LIBS coupled with multivariate analysis
Authors: GUPTA Vikas , RAI Abhishekh Kumar , KUMAR Tejmani , JUNJURI Rajendhar , KUMAR G Manoj , RAI A K
Published: April 2023

The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy (LIBS) coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various alloys. Thirteen old Indian coins in different years of circulation, (1922–1986) were selected for the study. The concentrations were determined by Calibration free LIBS (CF-LIBS) method. The concentration of cuprum (Cu) is negligible, and aluminum (Al) is maximum in the first five coins, and vice-versa in the remaining eight coins. Two different multivariate methods, Principal Component Analysis (PCA) and Soft Independent Modelling of Class Analogy (SIMCA) have been used to classify and identify the coins. PCA classified all thirteen samples into four main alloy categories. The discernment of unknown samples to their probable class membership of alloy was performed using SIMCA. The surface hardness (Brinell hardness number) is linearly correlated with the plasma temperature and LIBS intensity ratios. The sample surface of the first and fifth coin belongs to Al-alloy, having the least surface hardness, and it became harder for Cu–Ni alloy, Ni-brass alloy, and bronze alloy. The hardness of the surface is more for bronze sample twelve. It is also observed that the plasma temperature increases monotonically with the Brinell hardness number. This analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins.
Wear reliability and failure mechanism of inkjet-printed conductors on paperboard substrate
Authors: Fu Zhao , Tanninen Panu , Keskinen Jari , Lev Roman , Leminen Ville , Mäntysalo Matti
Published: April 2023

In this research, we conducted a wear test on inkjet-printed silver conductors using different loads and counter materials (two paperboards, brushed steel sheet, and sandpaper) with similar surface roughness values. The conductor’s reliability was characterized by resistance measurement, the failures and tested counter materials were analyzed using an optical microscope, profilometer, scanning electron microscope, and energy dispersive spectrometer. It was found that the counter material has a dominant impact on a conductor’s reliability and failure mechanism compared with load. The conductors were exceptionally reliable but subject to adhesive wear when tested by paperboards. They were also highly reliable when tested by brushed steel sheet although the silver became severely detached, and the conductivity was lost suddenly when a major scratch was caused by two-body and three-body abrasive wear mechanisms. Sandpaper rubbing caused the most severe silver detachment and quick loss of conductivity, as a large amount of small-size (5–15 µm) silicon carbide particles with sharp edges and corners caused a dense cutting effect via two-body abrasive wear (by cutting) mechanism. Additionally, the failures in almost all samples occurred in the areas in contact with the counter edges, suggesting that failure was accelerated by the edge effect. This study proves that inkjet-printed electronics on the investigated paperboard is exceptionally durable when rubbed by paperboards and steel sheets, and thus provides a reliable solution to intelligent packaging. To promote intelligent packaging, more paperboards, as well as approaches for reducing the edge effect can be investigated.
A brief introduction of electrode fabrication for proton exchange membrane water electrolyzers
Authors: Lin Xinlong , Seow Justin Zhu Yeow , Xu Zhichuan J
Published: April 2023

Proton exchange membrane water electrolyzer (PEMWE) is a major enabler of green hydrogen production. The development of water electrolyzers is a vital step in driving the progress of a hydrogen-based economy. The system inside the electrolyzer is a zero-gap cell featuring low ohmic resistance and boosted mass transport, leading to higher energy efficiency and minimized capital cost. Besides, utilizing PEM in the electrolyzer for sustainable hydrogen production enables the system to perform with many advantages, including superior energy efficiency, higher hydrogen purity, and high flexibility. Therefore, as PEM electrolyzers continue to evolve, sustainable hydrogen production on a larger scale will be realized in the near future. This review summarizes the status quo of PEM water electrolyzers in the past four years. We will start with a brief introduction of the core of a water electrolyzer, namely the membrane electrode assembly (MEA), which will be followed by an introduction of fabrication methods of MEA, including CCM methods, catalyst-coated electrode methods, and other innovative fabrication methods. Next, we will summarize recent attempts to modify electrodes and membranes in MEAs to promote the performance of PEMWE. Subsequently, catalyst development for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in MEA is discussed, highlighting novel HER/OER catalysts and strategies to reduce the content of noble metals. Lastly, conclusion and perspectives are provided to present a blueprint to inspire the future development of PEMWE.
Regularization of the factorization method with applications to inverse scattering
Authors: Harris Isaac
Published: April 2023

Here we discuss a regularized version of the factorization method for positive operators acting on a Hilbert Space. The factorization method is a qualitative reconstruction method that has been used to solve many inverse shape problems. In general, qualitative methods seek to reconstruct the shape of an unknown object using little to no a priori information. The regularized factorization method presented here seeks to avoid numerical instabilities in the inversion algorithm. This allows one to recover unknown structures in a computationally simple and analytically rigorous way. We will discuss the theory and application of the regularized factorization method to examples coming from acoustic inverse scattering. Numerical examples will also be presented using synthetic data to show the applicability of the method.