bluuebunny/crossref_metadata_2025 huggingface dataset:
Administration and Toxicity Profile of the Capizzi Interim Maintenance—Retrospective Study from a Tertiary Care Cancer Centre
Authors: Viswanathan Aarthi , Kumar Arun , Kaushik Prakruthi S. , Thumallapalli Avinash , Ramachandra C. , Aruna Kumari B. S. , Appaji Lingappa , Kumar Nuthan
Published: December 2021

Introduction The Capizzi-style methotrexate (MTX) is an integral part of acute lymphoblastic leukemia (ALL) treatment. The escalating dose of MTX originally used in the United Kingdom and Children’s Oncology Group protocols along with L-asparaginase has been modified in the Indian Childhood Collaborative Leukemia (ICiCLe) group protocol where L-asparaginase has been omitted. The data regarding the incidence of toxicities and ease of administration on the Capizzi-style interim maintenance is not robust.

Objectives We have compiled our experience with administration and toxicity profile in children with intermediate-risk ALL.

Materials and Methods A retrospective data collection of all children diagnosed with intermediate-risk ALL as per the ICiCLe risk stratification in the year 2019 was included in the analysis. Each cycle of MTX was started after ensuring an absolute neutrophil count of >750/mm3 and transaminases <2 upper limit of normal. As a unit protocol, pre- and post-MTX hydration was administered in all our children. No urine pH or midcycle biochemical parameter monitoring was done. Statistical analysis was done using Microsoft Excel and SPSS version 24 IBM Corp. in Armonk, New York, United States.

Results Forty-six children were included in the study. The median age of children in our study was 6 years (range: 1 year 2 months–12 years). Undernutrition was associated with a significant increase in toxicity (p = 0.02). Fifty-two percent of children had evidence of toxicity, elevated transaminases being the most common. There were recurring symptoms resulting in 53 episodes of toxicities overall. Incidence of toxicity was more in the early cycles (<3).

Conclusion The pre- and post-MTX hydration is an effective way to reduce toxicities with the Capizzi-style MTX and this course can be administered with ease on outpatient basis with minimal need for monitoring or admission.
Regional Gestational Age and Gender-Specific Birth Weight Reference Charts and its Comparison with Existing National and International Standards: A Cross-Sectional Study
Authors: Prakash Ajay , Venkatesh Soma , Sadagopan Srinivasan , Palanisamy Soundararajan
Published: December 2021

Background Growth potential is influenced by race, ethnicity, and environmental factors and assessment of growth using standardized charts is important for quality improvement initiatives in health care delivery and public health interventions of any nation.

Objective This article aims to develop regional gestational age and gender-specific reference for birth weight and to compare it with published literature.

Methodology This study was conducted in a teaching hospital in Puducherry, India and included 2,507 singleton babies. Babies with major congenital anomalies, maternal chronic illness, and nonavailability of first trimester dating scan were excluded. Detailed anthropometric measurement was done for these babies by single investigator as per established norms, their gestation- and sex-specific mean weight and weight percentiles were calculated and compared with existing data.

Results Both 10th and 90th percentiles were lower across all gestational ages compared with existing international standards. The proportion of late preterm and term small for gestational age (SGA) babies was 23% using Fenton-2013 reference chart, 14% using Intergrowth-21 chart, and 10% using the current study data (p < 0.0001). The proportion of large for gestational age (LGA) babies was 8.5%, using study data. Mean birth weight of male and female term babies born to primiparae were significantly higher compared with multiparae (p = 0.03 and 0.02, respectively).

Conclusion Indian babies may be overdiagnosed as SGA or underdiagnosed as LGA based on existing western standards in which our patient population is underrepresented. There is a need for gestational age-, gender-, and parity-specific regional growth charts for better characterization of anthropometric measures of Indian babies.
Experimental optimization of the fiber coupling efficiency of GaAs quantum dot-based photon sources
Authors: Nie Weijie , Sharma Nand Lal , Weigelt Carmen , Keil Robert , Yang Jingzhong , Ding Fei , Hopfmann Caspar , Schmidt Oliver G.
Published: December 2021

We present an efficient experimental method to optimize the combined extraction efficiencies and the far-field emission patterns of solid state-based single and entangled photon pair sources for efficient coupling to single mode fibers. This method is demonstrated for emitters based on droplet etched GaAs quantum dot nanomembranes attached to gallium phosphide solid immersion lenses using an adhesive layer of poly(methyl methacrylate). By varying the thickness of the latter, the optimization of both the extraction efficiency and the far-field emission pattern for single mode fiber coupling is facilitated. The applied method of far-field characterization is validated by benchmarking it against direct measurements of the single mode fiber coupling efficiency. Using this scheme, devices with a more than 150-fold enhanced free-space intensity compared to an unprocessed sample as well as a fiber coupling efficiency of 64% are achieved. In addition, the optimized device has been employed for on-demand generation of maximally entanglement photon pairs using two-photon excitation of the quantum dot bi-exciton exciton cascade. This universal approach for experimental optimization can be applied to other photonic nanostructures, including circular Bragg grating and micropillar cavities as well as monolithic microlenses.
Modeling the electron density distribution of high-enthalpy plasma jets through chemical reaction method
Authors: Wang Yuan , Li Xiaoping , Liu Donglin , Liu Yanming , Xu Jiahao , Bao Weimin
Published: December 2021

The plasma electron number density can be measured using probes, lasers, and microwaves. When the plasma jet temperature is higher than the upper limit of the temperature allowed by the probe, the probe cannot be used to measure the electron number density. Laser and microwave measurement methods are difficult to obtain the distribution characteristics of the electron number density. In this paper, a calculation method for equilibrium chemical reactions is proposed. The transport and thermodynamic properties are calculated according to the mole fraction of each species in the equilibrium conditions, and the electron number density distribution is obtained by the numerical calculation of chemical reactions and flow fields. Finally, the results of laser measurement and numerical calculation are compared, and the results are consistent. The numerical calculation results can reflect the electron number density distribution of the plasma jet.
Spectral amplitude modulation and dynamic near-field displaying of all-silicon terahertz metasurfaces supporting bound states in the continuum
Authors: Li Jitao , Li Jie , Zheng Chenglong , Yue Zhen , Yang Dingyu , Wang Silei , Li Mengyao , Zhang Yating , Yao Jianquan
Published: December 2021

The bound states in a continuum (BICs) are objective physical phenomena that defy conventional wisdom, and they exist in the radiating continuous spectrum but remain perfectly localized with non-radiation, which is different from the traditional bound states. In this paper, we report in theory and experiment the high thickness all-silicon terahertz (THz) metasurfaces supporting BIC and quasi-BIC, which is realized by simple pairs of elliptical pillars. Meanwhile, we used an extra optical pump to modulate the transmission amplitude difference between BIC and quasi-BIC metasurfaces, to complete the active control from “On” state to “Off” state. We utilize the abundant amplitude gradation of metasurfaces with different asymmetric degrees to develop the polarization-dependent THz near-field displaying application that can make the grayscale characteristics of a photograph reappear and also be dynamically controlled at On state to Off state.
Investigations on the effect of target angle on the stagnation layer of colliding laser produced plasmas of aluminum and silicon
Authors: Al-Juboori Haider M. , Malik Nadeem Ahmed , McCormack Tom
Published: December 2021

The temporal and spatial characteristics of two colliding laser produced plasmas are investigated over a range of flat to wedge-shaped targets for aluminum and silicon. Fast-gated visible photography was used to investigate how the length and width of the stagnation evolved over timescales from 300 to 500 ns with filters used to help to separate the emission from neutral and higher ionization states. The velocity of the stagnation layer was measured to be in the range of 3.8–6.6×106 cm/s. The length of the stagnation layer was observed to increase as the wedge angle decreased from 180° to 80°. Time-resolved spectra were also recorded, which helped to reveal the dominant ion stage in a given time interval. Based on this analysis, the longest and most homogenous stagnation layers appear to be comprised of mostly neutral and singly ionized species. Line widths were used to estimate electron densities of 1×1017cm−3 and temperatures of 1.9–2.1 eV, which remained fairly constant over the timescales observed. The analysis suggests that there is significant collisional reheating of the stagnation layer followed by radiative recombination and that the stagnation layer dynamics are not sensitive to small changes in mass.
Encapsulation of biobased fatty acid amides for phase change material applications
Authors: Betancourt-Jimenez Daniela , Wells Brandon , Youngblood Jeffrey P. , Martinez Carlos J.
Published: December 2021

A novel technique was used to produce macrocapsules containing a new type of biobased phase change material (fatty acid amides or FAAms) using a UV-curable polyester resin as the shell material. The production of capsules with varying phase change material (PCM) loading was achieved by generating core/shell droplets using a coaxial nozzle and subsequently curing them with a broad-spectrum light. All the capsules produced were approximately 3 mm in diameter independently of the process parameters used during generation. Also, the addition of rheology additives to the shell resin was proven successful in improving the capsules' final shape and the stability of the production process. The PCM loading of the capsules ranged from 40 to 54 vol. % with latent heats of fusion going from 36 to 51 J/g, respectively. The encapsulated FAAms showed higher melting points than the bulk FAAms in differential scanning calorimetry analysis as a result of the low thermal conductivity of the shell material. Results from thermogravimetric analysis showed that the capsules are thermally stable under 190 °C. The effect of core content on the mechanical properties of the capsules was also studied. The general trend observed from compression test results was the decrease in the capsules' mechanical performance when the core content was increased; however, it was also discovered that their failure response is highly dependent on the uniformity of the capsule's shell. Results from thermal cycling experiments showed that the thermal properties of the capsules remained unchanged after 50 cycles. Also, 95% of the capsules subjected to thermal cycling were able to withstand the PCM's volumetric changes without cracking or rupturing. Findings from this investigation are expected to lay the groundwork for the commercial use of biobased FAAms and potential replacement of petroleum-derived PCMs currently in the market.
Toward droplet dynamics simulation in polymer electrolyte membrane fuel cells: Three-dimensional numerical modeling of confined water droplets with dynamic contact angle and hysteresis
Authors: Hashemi Mohammad R. , Ryzhakov Pavel B. , Rossi Riccardo
Published: December 2021

This work focuses on three-dimensional simulation of the dynamics of droplets with contact-angle hysteresis. In order to consistently model the dynamics of the contact line, a combination of the linear molecular kinetic theory and the hydrodynamic theory is implemented in the present numerical method. Without presetting the contact line and/or the contact angle, such simulations are generally prone to irregularities at the contact line, which are mainly due to the imposition of the pinning and unpinning mechanisms associated with the hysteresis phenomenon. An effective treatment for this issue is proposed based on a simple procedure for calculating the nodal contact angle within the framework of enriched finite element/level set method. The resulting method also benefits from a manipulated momentum conservation equation that incorporates the effect of the liquid mass conservation correction, which is essentially important for simulations with a rather long (physical) run-time. In this paper, the proposed numerical model is validated against the previously published experimental data addressing the configuration of a water droplet on a tilted rough hydrophobic surface. In this test, the effect of the contact-line pinning as the underlying mechanism for droplet hysteresis phenomenon is also studied. The model is further employed to simulate a liquid droplet confined in a channel in the presence of air flow.
Compressible Falkner–Skan–Cooke boundary layer on a flat plate
Authors: Liu Zhiyong
Published: December 2021

The incompressible Falkner–Skan–Cooke (FSC) boundary layer is extended to the compressible regime on a flat plate, aiming at establishing a generalized model to facilitate the crossflow-related investigations. The compressible FSC flow is also compatible with the two-dimensional compressible Blasius boundary layer characterized by a self-similarity solution. A family of boundary layer with local self-similarity is obtained from an ordinary differential equation system. Pressure-gradient parameter and local swept angle are introduced to parameterize the crossflow, which can vary in both direction and magnitude. The results reveal that the crossflow is oriented toward the curvature center of the inviscid streamline, regardless of the direction of pressure gradient. The existence of crossflow results in moderate directional deviation of skin friction, while tiny difference is observed for the magnitude. In comparison, much less effect is observed on the thermal properties of boundary layer. Crossflow also leads to the distortion of vorticity inside boundary layer, accompanied by the production of helicity. In addition, it is revealed that cross-flow strength varies monotonously with the pressure-gradient parameter, while it varies non-monotonously with the local swept angle. The effects of Mach number and wall temperature on crossflow are investigated as well.
Single-layer ScI2: A paradigm for valley-related multiple Hall effect
Authors: He Zhonglin , Peng Rui , Dai Ying , Huang Baibiao , Ma Yandong
Published: December 2021

Valley-related multiple Hall effect in a two-dimensional lattice is of notable interest both for its fundamental physics and for its potential applications. In this work, by means of a low energy k·p model analysis, a mechanism of producing valley-related multiple Hall effects in the hexagonal lattice via strain engineering is proposed, and a general picture of valley-contrasted band inversion is developed. Through first-principles calculations, this mechanism is further established in a ferromagnetic hexagonal lattice of single-layer ScI2. Single-layer ScI2 prefers in-plane magnetization and exhibits neither anomalous valley Hall effects nor valley-polarized quantum anomalous Hall effects in nature. Remarkably, these two Hall effects emerge simultaneously in this system under 4.705% tensile strain and disappear simultaneously when further increasing strain, suggesting the exotic valley-related multiple Hall effect. The underlying physical mechanism is revealed using a model analysis and is generally applicable. Our work greatly enriches the valley-related physics.
Configural Processing at Birth: Evidence for Perceptual Organisation
Authors: Farroni Teresa , Valenza Eloisa , Simion Francesca , Umiltà Carlo
Published: December 2021

We report a series of ten experiments aimed to investigate the newborn's ability to discriminate the components of a visual pattern and to process the visual information that specifies the global configuration of a stimulus. The results reveal that: (i) newborn babies are able to distinguish individual elements of a stimulus (experiments 1A, IB, 1C, and ID); (ii) they can group individual elements into a holistic percept on the basis of Gestalt principles (experiments 2A and 3A); (iii) their spontaneous preferences cannot be easily modified by habituation (experiments 2B and 3B); and (iv) when horizontal stimuli are paired with vertical stimuli, they prefer the horizontal ones (experiments 4A and 4B).
Category Effects on the Processing of Plane-Rotated Objects
Authors: Vannucci Manila , Viggiano Maria Pia
Published: December 2021

We examined the effects of plane rotations on the identification of exemplars of three semantic categories. In the first two experiments line drawings belonging to three categories (animals, inanimate objects, and vegetables) were presented at four orientations (0°, 60°, 120°, and 180° of clockwise rotation). The response time was found to depend on stimulus category. In particular, whereas rotation effects were shown for animals, no effect at all was found for vegetables and only partial effects were found for inanimate objects. The unclear pattern found for inanimate objects was further examined in experiment 3 where the orientation effects on the identification of two subsets of the inanimate category were studied. The hypothesis of view-observation frequency was confirmed. In experiment 4, line drawings of objects at different orientations were presented in physically degraded versions. The minimum amount of visual information necessary to identify rotated stimuli was found to vary as a function of stimulus category as well. Results are discussed, combining current research on both viewpoint-dependence/independence and neural systems involved in category processing.
Perceptual Dimorphism in Visual Motion from Stationary Patterns
Authors: Naor-Raz Galit , Sekuler Robert
Published: December 2021

Fraser and Wilcox [1979 Nature (London)281 565–566] devised a series of complex stationary patterns that provoked episodes of compelling illusory motion, but only in about two-thirds of people tested. Using simplified versions of their stimuli, we have confirmed their claim of perceptual dimorphism. We show that the strength of the illusory motion depends upon stimulus duration, eccentricity, and contrast. The illusory motion does not require fluctuations in accommodation, as has been suggested for some other forms of illusory motion. Finally, we consider the relation of Fraser-type motion to other forms of illusory motion.
Oxidative regulation of chloroplast enzymes by thioredoxin and thioredoxin-like proteins in
Arabidopsis thaliana
Authors: Yokochi Yuichi , Fukushi Yuka , Wakabayashi Ken-ichi , Yoshida Keisuke , Hisabori Toru
Published: December 2021

Significance

Plants modulate photosynthesis activity in response to the surrounding environment. It is well known that the redox-responsive protein thioredoxin (Trx) activates photosynthesis-related enzymes in the light. However, the factors involved in deactivating them are not well understood. Recent in vitro experiments suggest that several Trx and Trx-like proteins serve as oxidation factors for Trx-targeted proteins; thus, we examined their functions in vivo. Consequently, we found that
f
-type Trx and two types of Trx-like proteins, Trx-like 2 and atypical Cys His-rich Trx, were involved in oxidative deactivation of photosynthesis-related enzymes (e.g., fructose-1,6-bisphosphatase, Rubisco activase, and the ATP synthase γ-subunit). Thus, this study reveals the functions of oxidation factors in vivo and elucidates the regulation system for photosynthesis in the dark.
Serum iron availability, but not iron stores, is lower in naturally menstruating than in oral contraceptive athletes
Authors: Alfaro‐Magallanes Víctor M. , Romero‐Parra Nuria , Barba‐Moreno Laura , Rael Beatriz , Benito Pedro J. , Díaz Ángel E. , Cupeiro Rocío , Peinado Ana B. ,   IronFEMME Study Group
Published: December 2021

This study measured serum markers of iron status in naturally menstruating and oral contraceptive (OC) athletes during the main hormonal milieus of these two profiles to identify potential differences confounding the diagnosis of iron deficiency in female athletes. Resting blood samples were collected from 36 naturally menstruating athletes during the early‐follicular phase (EFP), mid‐ late‐follicular phase (MLFP) and mid‐luteal phase (MLP) of the menstrual cycle. Simultaneously, blood samples were collected from 24 OC athletes during the withdrawal and active‐pill phase of the OC cycle. Serum iron, ferritin, transferrin, transferrin saturation (TSAT), C‐reactive protein (CRP), interleukin‐6 and sex hormones were analyzed. Naturally menstruating athletes showed lower levels of TSAT, iron and transferrin than OC athletes when comparing the bleeding phase of both profiles (p<0.05) as well as when comparing all analyzed phases of the menstrual cycle to the active pill phase of the OC cycle (p<0.05). Interestingly, only lower transferrin was found during MLFP and MLP compared to the withdrawal phase of the OC cycle (p>0.05), with all other iron markers showing no differences (p>0.05). Intracycle variations were also found within both types of cycle, presenting reduced TSAT and iron during menstrual bleeding phases (p<0.05). In conclusion, in OC athletes, serum iron availability, but not serum ferritin, seems higher than in naturally menstruating ones. However, such differences are lost when comparing the MLFP and MLP of the menstrual cycle with the withdrawal phase of the OC cycle. This should be considered in the assessment of iron status in female athletes.

Highlights

Naturally menstruating athletes present lower TSAT, iron and transferrin in all analyzed phases of the menstrual cycle compared to OC athletes during their active pill phase. However, both the mid‐late follicular and mid‐luteal phases of the menstrual cycle do not differ from the withdrawal phase of the oral contraceptive cycle.

Intracycle variations are found for TSAT and iron in both naturally menstruating and oral contraceptive athletes, which are mainly driven by a reduction in TSAT and iron during menstrual bleeding phases.

As serum iron availability changes significantly as a function of the athlete's hormonal status, it should be considered in the assessment of the athlete's iron status as well as standardise the phase of the menstrual cycle in which to assess iron markers to avoid misdiagnosis or misleading results.

In contrast, the assessment of iron stores through serum ferritin is substantially stable and the athlete's hormonal status does not seem to be of relevance for this purpose.
Magnetic modulation of Fano resonances in optically thin terahertz superlattice metasurfaces
Authors: Karmakar Subhajit , Varshney Ravi , Roy Chowdhury Dibakar
Published: December 2021

Optically thin metasurfaces operating at sub-skin depth thicknesses are intriguing because of their associated low plasmonic losses (compared to optically thick, beyond skin-depth metasurfaces). However, their applicability is restricted largely because of reduced free space coupling with incident radiations resulting in limited electromagnetic responses. To overcome such limitations, we propose enhancement of effective responses (resonances) in sub-skin depth metasurfaces through incorporation of a magneto-transport (giant magneto resistance) concept. Here, we experimentally demonstrate dynamic magnetic modulation of structurally asymmetric metasurfaces (consisting of superlattice arrangement of thin (∼10 nm each) magnetic (Ni)/nonmagnetic (Al) layers) operating in the terahertz (THz) domain. With increasing magnetic field (applied from 0 to 30 mT approximately, implies increasing superlattice conductivity), we observe stronger confinement of electromagnetic energy at the resonances (both in dipole and Fano modes). Therefore, this study introduces a unique magnetically reconfigurable ability in Fano resonant THz metamaterials, which directly improves their performances operating in the sub-skin depth regime. Our study can be explained by spin-dependent THz magneto-transport phenomena in metals and can stimulate the paradigm for on-chip spin-based photonic technology enabling dynamic magnetic control over compact, sub-wavelength, sub-skin depth metadevices.
Thermodynamic machine learning through maximum work production
Authors: Boyd Alexander B , Crutchfield James P , Gu Mile
Published: December 2021

Adaptive systems—such as a biological organism gaining survival advantage, an autonomous robot executing a functional task, or a motor protein transporting intracellular nutrients—must somehow embody relevant regularities and stochasticity in their environments to take full advantage of thermodynamic resources. Analogously, but in a purely computational realm, machine learning algorithms estimate models to capture predictable structure and identify irrelevant noise in training data. This happens through optimization of performance metrics, such as model likelihood. If such learning is physically implemented, is there a sense in which computational models estimated through machine learning are physically preferred? We introduce the thermodynamic principle that work production is the most relevant performance measure for an adaptive physical agent and compare the results to the maximum-likelihood principle that guides machine learning. Within the class of physical agents that most efficiently harvest energy from their environment, we demonstrate that an efficient agent’s model explicitly determines its architecture and how much useful work it harvests from the environment. We then show that selecting the maximum-work agent for given environmental data corresponds to finding the maximum-likelihood model. This establishes an equivalence between nonequilibrium thermodynamics and dynamic learning. In this way, work maximization emerges as an organizing principle that underlies learning in adaptive thermodynamic systems.
Spin manipulation and decoherence in a quantum dot mediated by a synthetic spin–orbit coupling of broken T-symmetry
Authors: Huang Peihao , Hu Xuedong
Published: December 2021

The electrical control of a spin qubit in a quantum dot (QD) relies on spin–orbit coupling (SOC), which could be either intrinsic to the underlying crystal lattice or heterostructure, or extrinsic via, for example, a micro-magnet. In experiments, micromagnets have been used as a synthetic SOC to enable strong coupling of a spin qubit in quantum dots with electric fields. Here we study theoretically the spin relaxation, pure dephasing, spin manipulation, and spin–photon coupling of an electron in a QD due to the synthetic SOC induced spin–orbit mixing. We find qualitative difference in the spin dynamics in the presence of a synthetic SOC compared with the case of the intrinsic SOC. Specifically, spin relaxation due to the synthetic SOC and deformation potential phonon emission (or Johnson noise) shows

B

0

5

(or B
0) dependence with the magnetic field, which is in contrast with the

B

0

7

(or

B

0

3

) dependence in the case of the intrinsic SOC. Moreover, charge noise induces fast spin dephasing to the first order of the synthetic SOC, which is in sharp contrast with the negligible spin pure dephasing in the case of the intrinsic SOC. These qualitative differences are attributed to the broken time-reversal symmetry (T-symmetry) of the synthetic SOC. An SOC with broken T-symmetry (such as the synthetic SOC from a micro-magnet) eliminates the ‘Van Vleck cancellation’ and causes a finite longitudinal spin–electric coupling that allows the longitudinal coupling between spin and electric field, and in turn allows spin pure dephasing. Finally, through proper choice of magnetic field orientation, the electric-dipole spin resonance via the synthetic SOC can be improved with potential applications in spin-based quantum computing.
Laser beam guiding in partially stripped magnetized quantum plasma
Authors: Kumar Punit , Singh Rathore Nisha
Published: December 2021

Relativistic and ponderomotive nonlinearities arising by the passage of a linearly polarized laser beam through a partially stripped magnetized quantum plasma are analyzed. The interaction formalism has been developed using the recently developed quantum hydrodynamic model. The effects associated with the Fermi pressure, quantum Bohm potential and electron spin have been incorporated. A nonparaxial, non-linear wave equation has been obtained by the use of source dependent expansion technique and spot size has been evaluated. The nonlinear relativistic self-focusing tends to focus the beam while the ponderomotive nonlinearity tends to defocus. The effect of magnetization and quantum effects on the spot size and the beam power have been studied.
Stable high-dimensional solitons in nonlocal competing cubic-quintic nonlinear media
Authors: Zhou Qi-ying , Li Hui-jun
Published: December 2021

We find and stabilize high-dimensional dipole and quadrupole solitons in nonlocal competing cubic-quintic nonlinear media. By adjusting the propagation constant, cubic, and quintic nonlinear coefficients, the stable intervals for dipole and quadrupole solitons that are parallel to the x-axis and those after rotating 45° counterclockwise around the origin of coordinate are found. For the dipole solitons and those after rotation, their stability is controlled by the propagation constant, the coefficients of cubic and quintic nonlinearity. The stability of quadrupole solitons is controlled by the propagation constant and the coefficient of cubic nonlinearity, rather than the coefficient of quintic nonlinearity, though there is a small effect of the quintic nonlinear coefficient on the stability. Our proposal may provide a way to generate and stabilize some novel high-dimensional nonlinear modes in a nonlocal system.
Block-coherence measures and coherence measures based on positive-operator-valued measures
Authors: Fu Liangxue , Yan Fengli , Gao Ting
Published: December 2021

We study block-coherence measures based on the resource theory of block-coherence and coherence measures based on positive-operator-valued measures (POVM). Several block-coherence measures are presented, including the block-coherence measure based on maximum relative entropy, the one-shot block-coherence cost under maximally block-incoherent operations, and the coherence measure based on coherent rank. Their relationships are obtained. Moreover, we describe the deterministic coherence dilution process by constructing block-incoherent operations. Based on the POVM coherence resource theory, we also propose two coherence measures and analyze their relationship.
Low-threshold lasing in a plasmonic laser using nanoplate InGaN/GaN
Authors: Zhi Ting , Tao Tao , Liu Xiaoyan , Xue Junjun , Wang Jin , Tao Zhikuo , Li Yi , Xie Zili , Liu Bin
Published: December 2021

Plasmonic nanolaser as a new type of ultra-small laser, has gain wide interests due to its breaking diffraction limit of light and fast carrier dynamics characters. Normally, the main problem that need to be solved for plasmonic nanolaser is high loss induced by optical and ohmic losses, which leads to the low quality factor. In this work, InGaN/GaN nanoplate plasmonic nanolaser with large interface area were designed and fabricated, where the overlap between SPs and excitons can be enhanced. The lasing threshold is calculated to be ~6.36 kW/cm2, where the full width at half maximum (FWHM) drops from 27 to 4 nm. And the fast decay time at 502 nm (sharp peak of stimulated lasing) is estimated to be 0.42 ns. Enhanced lasing characters are mainly attributed to the strong confinement of electromagnetic wave in the low refractive index material, which improve the near field coupling between SPs and excitons. Such plasmonic laser should be useful in data storage applications, biological application, light communication, especially for optoelectronic devices integrated into a system on a chip.
Four-inch high quality crack-free AlN layer grown on a high-temperature annealed AlN template by MOCVD
Authors: Liu Shangfeng , Yuan Ye , Sheng Shanshan , Wang Tao , Zhang Jin , Huang Lijie , Zhang Xiaohu , Kang Junjie , Luo Wei , Li Yongde , Wang Houjin , Wang Weiyun , Xiao Chuan , Liu Yaoping , Wang Qi , Wang Xinqiang
Published: December 2021

In this work, based on physical vapor deposition and high-temperature annealing (HTA), the 4-inch crack-free high-quality AlN template is initialized. Benefiting from the crystal recrystallization during the HTA process, the FWHMs of X-ray rocking curves for (002) and (102) planes are encouragingly decreased to 62 and 282 arcsec, respectively. On such an AlN template, an ultra-thin AlN with a thickness of ~700 nm grown by MOCVD shows good quality, thus avoiding the epitaxial lateral overgrowth (ELOG) process in which 3–4 μm AlN is essential to obtain the flat surface and high crystalline quality. The 4-inch scaled wafer provides an avenue to match UVC-LED with the fabrication process of traditional GaN-based blue LED, therefore significantly improving yields and decreasing cost.
Synthesis and characterization of ZnS-based quantum dots to trace low concentration of ammonia
Authors: Godavarti Uma Devi , Nagaraju P. , Yelsani Vijayakumar , Pushukuri Yamuna , Reddy P. S. , Dasari Madhavaprasad
Published: December 2021

In the present work, a solution-based co-precipitation method has been adopted to synthesize pure and cobalt-doped ZnS quantum dots and characterized by XRD, SEM, TEM with EDX, FTIR and gas sensing properties. XRD analysis has shown a single phase of ZnS quantum dots having a zinc blend structure. TEM and XRD line broadening indicated that the average crystallite size in the sample is in the range of 2 to 5 nm. SEM micrographs show spherical-shaped quantum dots. FTIR studies show that cobalt has been successfully doped into the ZnS cubic lattice. EDX spectra have analyzed the elemental presence in the samples and it is evident that the spectra confirmed the presence of cobalt (Co), zinc (Zn), oxygen (O), and sulphur (S) elements only and no other impurities are observed. The ZnS-based quantum dot sensors reveal high sensitivity towards 50 ppm of ammonia vapors at an operating temperature of 70 °C. Hence, ZnS-based quantum dots can be a promising and quick traceable sensor towards ammonia sensing applications with good response and recovery time.
Breaking stress of Coulomb crystals in the neutron star crust
Authors: Kozhberov A A
Published: December 2021

It is generally accepted that the Coulomb crystal model can be used to describe matter in the neutron star crust. In [1] we study the properties of deformed Coulomb crystals and how their stability depends on the polarization of the electron background. The breaking stress in the crust σmax at zero temperature was calculated based on the analysis of the electrostatic energy and the phonon spectrum of the Coulomb crystal. In this paper, I briefly discuss the influence of zero-point, thermal contributions and the internal magnetic field on σmax.
Investigation of Faddeev variant of embedding theory
Authors: Kuptsov S. S. , Paston S. A.
Published: December 2021

Faddeev variant of embedding theory is an example of using the embedding approach for the description of gravity. In the original form of the embedding approach, the gravity is described by an embedding function of a four-dimensional surface representing our spacetime. In Faddeev variant, the independent variable is a non-square vielbein, which is a derivative of embedding function in embedding theory. We study the possibility of the existence of extra solutions in Faddeev variant, which makes this theory non-equivalent to GR. To separate the degrees of freedom corresponding to extra matter, we propose a formulation of this theory as GR with an additional contribution to the action. We analyze the equations of motion for a specific class of solutions corresponding to a weak gravitational field. We construct a simple exact solution corresponding to arbitrary matter and nontrivial torsion, which is an extra solution in Faddeev variant in the absence of real matter.
A search for variability of hard X-ray emission from the Vela pulsar wind nebula
Authors: Krassilchtchikov A M , Pshirkov M S , Bykov A M
Published: December 2021

Observations of hard X-ray emission from the Vela pulsar wind nebula (PWN) with the ISGRI camera aboard INTEGRAL gamma-ray observatory have been analysed with the aim to search for possible flux variability on scales from weeks to years, which could be caused by short-term evolution of pulsar wind structures similar to those governing sharp flares and flux depressions observed in the sub-GeV emission of the Crab PWN. No statistically significant flux depressions or flares have been found in none of the considered energy ranges: 20-50 keV, 50-100 keV, and 100-200 keV, however some hints of flux instability can be seen in the former two bands. If the variability of the pulsar wind termination surface or instabilities of turbulent magnetic field in the nebula predicted by a number of PWN models indeed influence the synchrotron spectrum of such objects, the variability of the 1-30 MeV emission from the Vela PWN could be checked with the next generation of gamma-ray facilities, like eASTROGAM or HERMES.
Reconstruction of solar activity based on14C and other isotope profiles in lunar regolith
Authors: Frolov D , Pavlov A , Ostryakov V , Konstantinov A , Vasilyev G , Kudryavtsev I , Dergachev V
Published: December 2021

The Moon might be considered as an integral detector of Galactic Cosmic Rays (GCR) as it contains on its surface cosmogenic isotopes produced by nuclear reactions. Since the retrieval of lunar regolith cores by Apollo missions, there were numerous attempts to measure concentrations and depth profiles of those isotopes and reconstruct the level of cosmic radiation at 1AU at various time scales, ranging from thousands to millions of years. The data also contains encoded levels of solar activity, as the Sun affects the differential flux of GCRs in a well-known manner. All those attempts showed that our nuclear interaction codes, GEANT4 for example, need corrections to describe the lunar data, be it tweaking of cross-sections or any other methods. There are also such archives on Earth: ice cores and trees. Based on terrestrial modulation potential reconstruction we try to calibrate GEANT4 code in a transparent manner, and also present our estimates on the solar activity on time scales of 0.02 and 3 Myrs. The estimates made using our calibration procedure show values consistent with modern understanding of history of solar modulation potential, and demonstrate the necessity to establish an agreed correction method for the analysis of lunar data. We also compare our results and method with another estimation of solar modulation potential during the last 1 Myr.
Beryllium Isotopes in the PAMELA Experiment
Authors: Bogomolov E A , Vasilyev G I , Menn W
Published: December 2021

Analysis of the isotopic composition of nuclei in galactic cosmic rays (GCR) in the orbital experiment of the PAMELA collaboration makes it possible to study the problems of the origin and propagation of cosmic rays in the Galaxy. The data of the PAMELA magnetic spectrometer, due to their high statistical and methodological accuracy, ensured significant progress in the study of the isotopic composition of light nuclei from H to Be in GCR in the energy range ~ 0.1-1 GeV/nucleon and for the first time made it possible to estimate the contribution to GCR of Local Interstellar Sources (LIS) from close (∼ 100 pc) of recent (~ million years) supernova explosions. To date, the isotopic composition of beryllium nuclei in GCR has been measured only for 7Be./9Be, 10Be/9Be ratios in the energy range of ∼ 100 MeV/nucleon in the space experiments IMP 7/8, Voyager, Ulysses, ACE/CRIS and for 10Be/9Be in balloon experiment with a superconducting magnet ISOMAX-98 for energies 0.2-1.0 and 1.1-2.0 GeV/nucleon. In this work, using flight data PAMELA 2006-2014, on the rigidity of the detected nuclei and their velocity (time-of-flight analysis and ionization losses in the multilayer calorimeter of the instrument), a new analysis of the isotopic composition of beryllium nuclei in the energy range of ~ 0.1-1.4 GeV/nucleon has been carried out. The results of isotopic analysis of beryllium nuclei in GCR (spectra 7Be, 9Be, 10Be and 7Be/9Be, 10Be/9Be - ratio depending on the rigidity and energy of nuclei) in comparison with the existing measurement and calculation data will be presented.
Stochastic analysis of dynamic processes in the solar activity
Authors: Kostina E Y , Khusaenova E V , Andreev A O , Hudec R , Nefedyev Y A
Published: December 2021

Natural processes existing in complex objects of inanimate and living matter are of a stochastic and non-equilibrium nature. The main problem in the study of such systems is to determine the value of entropy as a quantitative measure of the uncertainty and systematicity of states of dynamical systems in different phase spaces. This paper presents a new method for analyzing active processes of solar dynamics using the theory of non-Markov random discrete processes (NMRDP). The NMRDP theory is based on the Zwanzig-Mori kinetic equations in a finite-difference discrete interpretation. This is consistent with the concept of non-equilibrium statistical condensed matter physics. Qualitative information about the set of behavioral patterns, relaxation processes, dynamic characteristics and internal properties of solar activity can be obtained using NMRDP modeling by the author’s methodological approach developed in this work. This approach is focused on the analysis of spectral frequency memory functions, dynamic orthogonal parameters, phase transformations, relaxation and kinetic processes and self-organization in complex physical systems. In this work, for modeling NMRDP, the author’s software package APSASA (automated program for solar activity stochastic analysis) was used, which also allows predicting the trend of solar activity for a limited period of time. Modeling NMRDP associated with active processes occurring on the Sun made it possible to build a mathematical model with whose help it is possible to study the regularities and randomness of stochastic processes, as well as to reveal the patterns arising from the recurrence and periodicity of solar activity.
Analysis of modern observations of meteor showers based on PTM methods
Authors: Sharafutdinova A A , Andreev A O , Nefedyev Y A , Hudec R , Demina N Y
Published: December 2021

The work is focused on the analysis of modern observations of meteoroids included in the data bank formed by both professional researchers and amateur astronomers. Based on the modern physical theory of meteoroids (PTM), a new method for analyzing measurements developed, which provides the accuracy comparable with the results of radar observations. Due to the fact that the accuracy of the new method for analyzing meteoroids observations has increased significantly, it became possible to process observations of the Perseid and Leonid showers over a period of 120 years. The use of PTM made it possible for the first time to explain the distribution of meteor echo signals observed at an altitude of 2 MHz, at which the upper part of this distribution refers to an altitude of 140 km. In the process of work, a database of orbital characteristics of meteoroids was created. A method has been developed for modeling the probability of hitting a certain area of a meteor particle with a mass greater than a certain specified value and determining the density of a meteor shower from radio observations as well as a new “tomography” method for calculating the density distribution of sporadic meteors in the sky using radar observations of meteors at the same station with a goniometer. The method allows calculating the density of a meteor shower on the celestial sphere with an angular resolution of 2°. The use of these methods served as a proof that the distribution density of meteoroid showers on the celestial sphere has two planes of symmetry: the first coincides with the plane of the ecliptic, passing through the poles of the Earth, the other one is perpendicular to the plane of the ecliptic.
Changes in solar activity based on radiocarbon data and climate variations in the interval 8000 - 1000 BC
Authors: Dergachev V A , Kudryavtsev I V
Published: December 2021

This work examines the change in the activity of the Sun based on the reconstruction of the heliospheric modulation potential in the time interval 8000 - 1000 BC. Reconstructions of this potential were obtained using radiocarbon data, taking into account the influence of changes in the Earth’s climate. A comparison is made of the variations in the activity of the Sun with the global surface temperature. It is shown that variations in global temperature during this period could be the result of changes in solar activity. So high solar activity could lead to recorded temperature maximums around 7000 and 5300 BC. The drop in temperature in the range 3000-1000BC could be the result of low solar activity.
Development of detector pixels based on silicon photomultipliers for the Cherenkov gamma-ray telescope TAIGA-IACT
Authors: Bogdanov A A , Tuboltsev Yu V , Chichagov Yu V , Krassilchtchikov A M
Published: December 2021

The design and scheme of signal readout from silicon photomultipliers OnSemi MicroFJ-60035 used as sensitive elements (pixels) of a new detector cluster for the camera of the Cherenkov gamma-ray telescope TAIGA-IACT are developed. The design of the developed pixel follows the shape of the photomultiplier tube XP1911 using in the first generation clusters, and that provides compatibility of the new cluster with the telescope camera. Due to the adjustable gain, the developed scheme allows one to detect and digitize signals in a wide dynamic range from several to 10 000 photons.
Influence of non-gravitational effects on the Centaur upper stage of the Surveyor 2 spacecraft
Authors: Martyusheva A A , Devyatkin A V
Published: December 2021

A small near-Earth asteroid, discovered by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) on September 17, 2020, turned out to be a part of the Centaur upper stage of the Surveyor 2 spacecraft launched by NASA on September 20, 1966 and subsequently crashed. This object had moved in a heliocentric orbit until it was under the influence of Earth’s gravitational field. As a result, a close approach to the Earth took place at a distance of about 50000 km on December 1, 2020. Despite the fact that the Centaur escaped back into a new orbit around the Sun in March 2021, it is of special interest for research, in particular, to consider the impact of non-gravitational effects on its orbital characteristics. Thus, it was calculated that the maximum displacement of the object trajectory due to the influence of solar radiation pressure over 15 years (the next close approach will take place in 2036) can be about 10.3-13.5 km, depending on the albedo. Estimations of the Yarkovsky effect showed that the magnitude of the expected change in the semi-major axis of Centaur’s orbit is from -8.1 • 10−13 to 1.6 10−13, depending on the angle of its rotation.