bluuebunny/crossref_metadata_2025 huggingface dataset:
Convolutional neural networks as an alternative to Bayesian retrievals for interpreting exoplanet transmission spectra
Authors: Ardévol Martínez F. , Min M. , Kamp I. , Palmer P. I.
Published: March 2022

Context. Exoplanet observations are currently analysed with Bayesian retrieval techniques to constrain physical and chemical properties of their atmospheres. Due to the computational load of the models used to analyse said observations, a compromise is usually needed between model complexity and computing time. Analyses of observational data from future facilities, such as the James Webb Space Telescope (JWST), will require more complex models, and this will increase the computational load of retrievals, prompting the search for a faster approach for interpreting exoplanet observations.

Aims. Our goal is to compare machine learning retrievals of exoplanet transmission spectra with nested sampling (Bayesian retrieval) and to understand if machine learning can be as reliable as a Bayesian retrieval for a statistically significant sample of spectra while being orders of magnitude faster.

Methods. We generated grids of synthetic transmission spectra and their corresponding planetary and atmospheric parameters, with one using free chemistry models and the other using equilibrium chemistry models. Each grid was subsequently rebinned to simulate both Hubble Space Telescope, Wide Field Camera 3 (WFC3), and JWST Near-InfraRed Spectrograph observations, yielding four datasets in total. Convolutional neural networks (CNNs) were trained with each of the datasets. We performed retrievals for a set of 1000 simulated observations for each combination of model type and instrument with nested sampling and machine learning. We also used both methods to perform retrievals for real WFC3 transmission spectra of 48 exoplanets. Additionally, we carried out experiments to test how robust machine learning and nested sampling are against incorrect assumptions in our models.

Results. Convolutional neural networks reached a lower coefficient of determination between predicted and true values of the parameters. Neither CNNs nor nested sampling systematically reached a lower bias for all parameters. Nested sampling underestimated the uncertainty in ~8% of retrievals, whereas CNNs correctly estimated the uncertainties. When performing retrievals for real WFC3 observations, nested sampling and machine learning agreed within 2σ for ~86% of spectra. When doing retrievals with incorrect assumptions, nested sampling underestimated the uncertainty in ~12% to ~41% of cases, whereas for the CNNs this fraction always remained below ~10%.
Monte Carlo simulation of sugar synthesis on icy dust particles intermittently irradiated by UV in a protoplanetary disk
Authors: Takehara Hitoshi , Shoji Daigo , Ida Shigeru
Published: March 2022

Context. While synthesis of organic molecules in molecular clouds or protoplanetary disks is complex, observations of interstellar grains, analyses of carbonaceous chondrites, and UV photochemistry experiments are rapidly developing and are providing constraints on and clues to the complex organic molecule synthesis in space. This motivates us to construct a theoretical synthesis model.

Aims. We developed a new code to simulate global reaction sequences of organic molecules and apply it to sugar synthesis by intermittent UV irradiation on the surface of icy particles in a protoplanetary disk. Here we show the first results of our new simulation.

Methods. We applied a Monte Carlo method to select reaction sequences from all possible reactions, using the graph-theoretic matrix model for chemical reactions and modeling reactions on the icy particles during UV irradiation.

Results. We obtain results consistent with the organic molecules in carbonaceous chondrites and obtained by experiments, albeit through a different pathway from the conventional formose reactions previously suggested. During UV irradiation, loosely bonded O-rich large molecules are continuously created and destroyed. After UV irradiation is turned off, the ribose abundance rapidly increases through the decomposition of the large molecules via breakage of O−O bonds and replacements of C−OH by C−H to reach O/C = 1 for sugars. The sugar abundance is regulated mostly by the total atomic ratio H/O of starting materials, but not by their specific molecular forms. Deoxyribose is simultaneously synthesized, and most of the molecules end up in complexes with C-rich molecules.
Performance guarantee of the jump neighborhood for scheduling jobs on uniformly related machines
Authors: Muñoz Felipe T. , Pinochet Alejandro A.
Published: March 2022

We study the worst case performance guarantee of locally optimal solutions for the problem of scheduling jobs on uniformly related parallel machines with the objective of minimizing the total weighted completion time. The quality of locally optimal solutions under the jump neighborhood is analyzed, which consists of iteratively moving a single job from one machine to another, improving the total weighted completion time in each iteration and stopping once improvement is no longer possible. We propose an upper bound for the total weighted completion time for the solutions obtained by this local search, and upper and lower bounds for the performance guarantee of the obtained locally optimal solutions. Additionally, the case of identical parallel machines is analyzed.
Decision and coordination analysis of extended warranty service in a remanufacturing closed-loop supply chain with dual price sensitivity under different channel power structures
Authors: Zhu Xiaodong , Ding Lian , Guo Yajie , Zhu Huiting
Published: March 2022

This paper studies the impact of dual price sensitivity (product price sensitivity and extended warranty service price sensitivity) on the decision of the closed-loop supply chain (CLSC) where manufacturers are responsible for recycling and providing extended warranty service under different channel power structures. First, the dynamic game model is used to describe the three channel power structure models of centralized (C), Manufacturer-led Stackelberg (MS), and Retailer-led Stackelberg (RS). Then, mathematical optimization and reverse induction are used to derive supply chain decision-making and performance levels. On this basis, we further designed a contract to coordinate the supply chain, and use numerical examples to analyze and verify the impact of remanufacturing cost savings and dual price sensitivity on the supply chain system. Research shows that channel power structures, remanufacturing cost savings and dual price sensitivity all have an important impact on the supply chain and corporate profits.
Air, bodies, affects and quarantines: containing fear and constructing atmospheres of security and tranquillity
Authors: Bonastra Quim
Published: March 2022

This article will investigate, based on the idea of “atmosphere”, the possibilities raised by the study of the containment of fear in the case of an epidemic in nineteenth-century Marseille. Following Derek P. McCormack, atmospheres will be understood from different and, as will become clear, complementary perspectives. The first is atmosphere understood in its meteorological sense, that is the zone of gaseous material surrounding our bodies and which will be treated here as something that can play a role in the onset and dissemination of epidemics. The second is atmosphere in an affective sense, a set of “shared feelings and moods in a particular space or environment”. Drawing on the contributions of Gernot Böhme on the aesthetics of the reception and production of atmospheres, it will be argued that the atmospheres of security and tranquillity that emerged in Marseille in the presence of epidemic danger were low-intensity atmospheres with the capacity to last over time. Within these atmospheres, elements of a diverse nature were combined, some continuous and others more exceptional, which, taken together, helped create an affective community.
Technology and Sleep Quality: Friend or Foe? Let the Exergames Come
into Play!
Authors: Rosa João Paulo Pereira , Gentil Paulo , Knechtle Beat , Vancini Rodrigo Luiz , Campos Mário Hebling , Vieira Carlos Alexendre , Andrade Marília Santos , de Lira Claudio Andre Barbosa
Published: March 2022

Low sleep quality is associated with many health problems. Although physical
exercise is a nonpharmacological tool that positively impacts sleep quality,
there are many barriers (lack of energy, lack of motivation, lack of skills,
lack of resources, and fear of injury) for people to adopt an active lifestyle.
Exergames are an alternative way of physical exercise that are funnier and more
attractive than traditional forms of physical exercise and, therefore, has the
potential to increase adherence to a physical exercise program. Given that
previous studies showed that exergames presents similar physiological and
psychological outcomes to traditional forms of exercise, we aimed to discuss in
this narrative review potentials applications, limitations and perspectives of
using exergames to improve sleep quality.
Correction of the Saddle Nose Deformity Using the “Push Up” Technique
Authors: Toriumi Dean M. , Kovacevic Milos
Published: March 2022

The saddle nose deformity typically occurs after the loss of underlying septal support with loss of projection of the middle nasal vault. This creates a saddling effect as the upper lateral cartilages contract and forms a dip in the profile. The saddle nose deformity can occur from many different etiologies, including septal hematoma, fracture of the septum after trauma, disruption of the dorsal L-strut support after septoplasty, and metabolic disorders resulting in the loss of septal support. In most cases, the nasal bones remain in their native position creating a discrepancy in dorsal height and deformity. Correction of the saddle nose deformity can be performed using one of the two primary approaches. The most basic option is to simply fill the defect with a cartilage onlay graft (solid graft, diced cartilage and fascia, and so on) to create a normal dorsal line. This approach can be effective in many cases. Over time, the onlay graft may descend and create deformity or become visible. The other approach involves opening the middle nasal vault, placing spreader grafts, and reconstituting the dorsal L-strut, performing septal reconstruction or extracorporeal septoplasty. In this paper, we present our technique of repairing the saddle nose deformity using a “push up” method that preserves the middle vault anatomy and reconstitutes the proper projection of the middle-third of the nose.
Gas–liquid transition of van der Waals fluid confined in fluctuating nano-space
Authors: Zhang Hongguang , Chen Changsheng , Zhang Xianren , Doi Masao
Published: March 2022

Gas–liquid transition is generally a complex process, which involves nucleation of droplets and their growth by evaporation–condensation or collision–coalescence processes. Here, we focus on a microscopic system in which there is only one liquid droplet at most. In this case, we can develop an equilibrium theory for the formation of the droplet in the gas phase using the classical nucleation theory. We use the van der Waals fluid model with surface tension and calculate the size fluctuation of the droplet for various confinement conditions, NVT (in which the volume V of the system is fixed), NPT (in which the pressure P of the system is fixed), and NBT (in which the system is confined in a nano-bubble immersed in a host liquid, where both V and P can fluctuate). We show that in the NBT system, the size flexibility along with space confinement induces a wealth of properties that are not found in NVT and NPT. It exhibits richer phase behaviors: a stable droplet appears and coexists with the pure gas phase and/or pure liquid phase. When compared to the NVT system, the NBT system shows not only the oscillatory fluctuation between the two stable states but also a large fluctuation in the total volume and the pressure.
Impingement dynamics of droplets on mildly heated walls at initial and later stages
Authors: Zhang Fangfang , Li Xiangyu , Li Huajie , Tang Jingdan , Shen Zhen , Li Guopei , Jin Tingxiang , Yuan Pei
Published: March 2022

The impingement dynamics of water droplets on a heated wall at initial and later stages are experimentally investigated. First, the effects of the wall temperature and the Weber number on the water droplet spreading characteristics are considered. A constant contact radius evaporation mode is observed during most of the evaporation. The wall temperature has little influence on the spreading characteristics at the initial stages. The Weber number greatly influences the spreading characteristics, such as the spreading dynamic behavior, maximum spreading time, spreading height, diameter, and contact angle, at the initial stages. At the later stages of spreading, the heating temperature has a relatively greater impact on the rate of linear change of the residual volume, whereas the impact of the Weber number on that is relatively small. Subsequently, the effect of evaporation on the impingement dynamics is investigated. The spreading characteristics of the water droplet are compared with those of an ionic liquid droplet (which does not experience evaporation), whereby the spreading factor increases and the volume remains unchanged with the increasing contact time in the absence of the evaporation effect.
Annealing-temperature-dependent evolution of hydrogen-related donor and its strong correlation with X-photoluminescence center in proton-irradiated silicon
Authors: Kiyoi Akira , Kawabata Naoyuki , Nakamura Katsumi , Fujiwara Yasufumi
Published: March 2022

We have investigated the formation and decay of hydrogen-related donors (HDs) and irradiation-induced intrinsic defects. N-type m:Cz and FZ silicon wafers, which were irradiated with 2 MeV protons and subsequently annealed at 100–600 °C, were analyzed using spreading resistance profiling and photoluminescence (PL). HDs formed at 260 °C and then disappeared in two stages at 400–440 and 500–540 °C. This decay behavior indicates the existence of two types of HDs with different thermal stabilities. PL measurements showed interstitial silicon clusters (W and X center), a carbon–oxygen complex (C center), and exciton lines bound to unknown shallow centers. The origin of the HDs was investigated based on the correlation of the formation and decay temperatures between HDs and irradiation-induced defects. The predominant defects at the early stage of annealing, such as the C and W centers, are ruled out as candidates for the core defects of HDs because annealing above 260 °C is indispensable for the HD formation. In contrast, the X center was found to be thermally generated above 200 °C and disappeared at 580 °C. The similarity of the formation and decay temperatures between the X and HD centers suggests that HDs are associated with the formation of the interstitial silicon-related defects attached to hydrogen. Our results suggest that controlling the formation of interstitial silicon-related defects is important for realizing desirable doping profiles with high accuracy and reproducibility for power devices. Annealing above 400 °C exclusively provides thermally more stable HDs, leading to the realization of more rugged power devices.
Cubic boron nitride as a material for future electron device applications: A comparative analysis
Authors: Chilleri John , Siddiqua Poppy , Shur Michael S. , O'Leary Stephen K.
Published: March 2022

Drawing upon a collection of electron transport results, coupled with a variety of other material parameters, we set expectations on the upper limits to device performance of zinc blende boron-nitride-based electron devices. We examine how the device performance varies with the device length-scale, noting that a diversity of physical regimes are experienced as the device length-scale reduces from that corresponding to a long electron device, i.e., 100 μm, to the sub-micron level. Results corresponding to zinc blende boron nitride are contrasted with those associated with germanium, silicon, gallium arsenide, the 4H-phase of silicon carbide, wurtzite gallium nitride, and diamond. The electron device performance metrics that we focus upon for the purposes of this analysis include the effective mobility, accounting for the transition between the ballistic and the collision-dominated electron transport regimes, and the cutoff frequency.
A combined helium atom scattering and density-functional theory study of the Nb(100) surface oxide reconstruction: Phonon band structures and vibrational dynamics
Authors: McMillan Alison A. , Thompson Caleb J. , Kelley Michelle M. , Graham Jacob D. , Arias Tomás A. , Sibener S. J.
Published: March 2022

Helium atom scattering and density-functional theory (DFT) are used to characterize the phonon band structure of the (3 × 1)-O surface reconstruction of Nb(100). Innovative DFT calculations comparing surface phonons of bare Nb(100) to those of the oxide surface show increased resonances for the oxide, especially at higher energies. Calculated dispersion curves align well with experimental results and yield atomic displacements to characterize polarizations. Inelastic helium time-of-flight measurements show phonons with mixed longitudinal and shear-vertical displacements along both the ⟨1̄00⟩, Γ̄X̄ and ⟨11̄0⟩, Γ̄M̄ symmetry axes over the entire first surface Brillouin zone. Force constants calculated for bulk Nb, Nb(100), and the (3 × 1)-O Nb(100) reconstruction indicate much stronger responses from the oxide surface, particularly for the top few layers of niobium and oxygen atoms. Many of the strengthened bonds at the surface create the characteristic ladder structure, which passivates and stabilizes the surface. These results represent, to our knowledge, the first phonon dispersion data for the oxide surface and the first ab initio calculation of the oxide’s surface phonons. This study supplies critical information for the further development of advanced materials for superconducting radiofrequency cavities.
Complex viscosity of poly[n]catenanes including olympiadanes
Authors: Singhal D. , Kanso M. A. , Coombs S. J. , Giacomin A. J.
Published: March 2022

Chains of mechanically interlocking or intersecting organic rings, called poly[n]catenanes, afford interesting opportunities to study the role of orientation in suspensions. We call poly[5]catenanes olympiadanes. In this work, we use general rigid bead-rod theory to arrive at general expressions, from first principles, for the complex viscosity of poly[n]catenane suspensions. General rigid bead-rod theory relies entirely on suspension orientation to explain the elasticity of the liquid. We obtain analytical expressions for the complex viscosity of poly[n]catenanes for both n even and odd, for both mechanically interlocking and intersecting rings, and for identically sized rings. We restrict our analysis to evenly spaced poly[n]catenanes of orthogonal adjacency. We find that the parts of the complex viscosity for intersecting and interlocking rings, when made dimensionless with the polymer contribution to the zero-shear viscosity, match. We find good agreement with the available complex viscosity measurements for molten intersecting polystyrene poly[1,3]catenanes, but not so for poly[2]catenanes. We next calculate space filling equilibrium structures of these poly[1–3]catenanes, only to discover that each polystyrene ring looks more like a bead. We find that, for these polystyrene poly[n]catenanes and for good agreement with the available complex viscosity measurements, the shish-kebab theory suffices.
Structural and magnetic properties of DyCrO3
Authors: Sibanda E. T. , Prinsloo A. R. E. , Sheppard C. J. , Mohanty P.
Published: March 2022

In this contribution, the structural and magnetic properties of DyCrO3 are studied, along with the magnetocaloric effect in this compound. The susceptibility as a function of temperature, χ(T), indicates that DyCrO3 has a G-type antiferromagnetic behaviour with weak ferromagnetism below Néel temperature, TNCr, at 147.1 ± 0.1 K, attributed to the ordering of Cr moments. The Dy moments orders antiferromagnetically below the spin reorientation temperature TSR = 4.81 ± 0.04 K. The dependence of magnetization on the applied magnetic field, Mμ0H, shows a behaviour that corresponds to the χ(T) data. Arrott plots reflect the various magnetic orderings with a change in the gradient of the curves. For the first time, the magnetocaloric effect of sol-gel synthesized DyCrO3 is studied having an average particle size 215 ± 3 nm as obtained from transmission electron microscopy (TEM). Large magnetocaloric effects (MCE) are observed in the temperature range of 10 to 80 K for DyCrO3. The compound shows a relatively large magnetic entropy change (ΔSM) of 21 J.Kg−1.K−1 and relative cooling power (RCP) of 498 J.Kg−1 at 7 T and 10 K. Assuming the relations |ΔSmT,H|=a(H)n and RCP=CH1+1δ, with critical exponents n = 1 and δ → ∞ were obtained from the linearization, confirming the weak ferromagnetic behaviour.
Overtime claiming among Australian doctors-in-training
Authors: Coulshed Andrew , Fernandes Brian , Hettige Sanjay
Published: March 2022

Objective To quantify patterns of overtime among doctors-in-training in New South Wales and to explore the reasons doctors-in-training cite for not claiming overtime worked. Methods A confidential online self-reporting survey was conducted of post-graduate doctors-in-training, working in hospitals in NSW, from post-graduate year 1 through to completion of specialist training. Questions sought to determine the average amount of overtime worked, overtime claiming patterns, and reasons why overtime was not claimed. Comparisons were made by level of training and specialty training pathway. Results A total of 1351 valid responses were received. Unrostered overtime was extremely common, as was underpayment for work completed. Though 73.5% of respondents reported working at least 5 h of unrostered overtime per fortnight, only 15.6% of respondents reported claiming all their unrostered overtime, and among those who did claim overtime, only 45.5% reported being paid the amount in full. Common reasons for not claiming overtime included workplace cultural expectations (37.0%), and overtime not falling under approved reasons (32.6%). There were statistically significant differences (P < 0.001) in all response categories between critical care, physician and surgical training pathways. Conclusions The survey data demonstrated a significant disconnect between expectations and reality of working hours among doctors-in-training. This is indicative of concerns regarding loss of income, impaired ability to plan workforce allocation due to hidden workload, and possibly impaired wellbeing.
Have ‘mainstream’ economics journals ‘missed the bus’ on wetland, marine and coastal ecosystems?
Authors: Mukhopadhyay Pranab , Tapaswi M. P.
Published: March 2022

We assess research published in Scopus-indexed journals from 1981 on the economics of wetlands, marine and coastal ecosystems. We used scientometric techniques to extract records of all journal articles with the keyword economics, in combination with wetland, marine or coastal ecosystems in their titles, abstracts or keywords. We compared this with publications in the top 10 journals in economics in the Scimago database. We found that these top economics journals have ignored this topic and, thus, ‘missed the bus’ on an important economic resource. They published only eight articles with these word combinations in their entire history, even though these ecosystems contribute significantly to human wellbeing. However, new journals that have been more inclusive of these themes in ecological and environmental economics have emerged. Our study adds to the literature on wetland, marine and coastal ecosystems by providing a systematic study of publications in Scopus-indexed journals on this theme. Whereas a number of studies have reviewed the literature with the objective of documenting methodological advances, our study complements them by looking at the spatial and temporal spread of the contributors. We also provide an insight on which journals are most frequently publishing research in this thematic area.
Linguistic measures of psychological distance track symptom levels and treatment outcomes in a large set of psychotherapy transcripts
Authors: Nook Erik C. , Hull Thomas D. , Nock Matthew K. , Somerville Leah H.
Published: March 2022

Significance

Using language to “distance” ourselves from distressing situations (i.e., by talking less about ourselves and the present moment) can help us manage emotions. Here, we translate this basic research to discover that such “linguistic distancing” is a replicable measure of mental health in a large set of therapy transcripts (
N
= 6,229). Additionally, clustering techniques showed that language alone could identify participants who differed on both symptom severity and treatment outcomes. These findings lay the foundation for 1) tools that can rapidly identify people in need of psychological services based on language alone and 2) linguistic interventions that can improve mental health.
WDR82-binding long noncoding RNA lncEry controls mouse erythroid differentiation and maturation
Authors: Yang Shangda , Sun Guohuan , Wu Peng , Chen Cong , Kuang Yijin , Liu Ling , Zheng Zhaofeng , He Yicheng , Gu Quan , Lu Ting , Zhu Caiying , Wang Fengjiao , Gou Fanglin , Yang Zining , Zhao Xiangnan , Yuan Shiru , Yang Liu , Lu Shihong , Li Yapu , Lv Xue , Dong Fang , Ma Yanni , Yu Jia , Ng Lai Guan , Shi Lihong , Liu Jing , Shi Lei , Cheng Tao , Cheng Hui
Published: March 2022

Hematopoietic differentiation is controlled by both genetic and epigenetic regulators. Long noncoding RNAs (lncRNAs) have been demonstrated to be important for normal hematopoiesis, but their function in erythropoiesis needs to be further explored. We profiled the transcriptomes of 16 murine hematopoietic cell populations by deep RNA sequencing and identified a novel lncRNA, Gm15915, that was highly expressed in erythroid-related progenitors and erythrocytes. For this reason, we named it lncEry. We also identified a novel lncEry isoform, which was the principal transcript that has not been reported before. lncEry depletion impaired erythropoiesis, indicating the important role of the lncRNA in regulating erythroid differentiation and maturation. Mechanistically, we found that lncEry interacted with WD repeat–containing protein 82 (WDR82) to promote the transcription of Klf1 and globin genes and thus control the early and late stages of erythropoiesis, respectively. These findings identified lncEry as an important player in the transcriptional regulation of erythropoiesis.
Closed conformal Killing–Yano initial data
Authors: García-Parrado Alfonso , Khavkine Igor
Published: March 2022

Through an exhaustive search, we produce a five-parameter family of propagation identities for the closed conformal Killing–Yano (cCYK) equation on two-forms, which hold on an Einstein cosmological vacuum spacetime in any dimension n > 4. It is well-known that spacetimes admitting a non-degenerate two-form of this type are exhausted by the Kerr-NUT-(A)dS family of exact higher dimensional black hole solutions. As a consequence, we identify a set of necessary and sufficient conditions ensuring that the cosmological vacuum development of an initial data set for Einstein’s field equations admits a cCYK two-form. We refer to these conditions as closed conformal Killing–Yano initial data equations. The four-dimensional case is special and is treated separately, where we can also handle the conformal Killing–Yano equation without the closed condition.
Magnetotransport properties of the quantum spin Hall and quantum Hall states in an inverted HgTe/CdTe and InAs/GaSb quantum wells
Authors: Mawrie Alestin
Published: March 2022

The quantum spin Hall (QSH) states discovered in an inverted band of InAs/GaSb and HgTe/CdTe quantum wells categorize them among the very superior candidates for topological insulators. In the presence of a magnetic field, these QSH states persist up to a magnetic field equal to the critical field, beyond which the edge states would consist of normal quantum Hall (QH) states. We provide the expression of this critical field which is found consistent with some previous literature. The critical field partitioned the spectrum into two types of quantum states, viz, the QSH and QH states. We present a theoretical study of the magnetotransport properties based on the Bernevig–Hughes–Zhang Hamiltonian that describes these QSH states. Our results of the Hall conductivity show the different responses at these two different topological regions. Around the low Fermi energy level, the system has a high Hall conductivity in the QH region, while the same is less dominant in the QSH region. Our results of the Hall conductivity thus help differentiate the type topological phase of the given quantum well.
Field induced spin freezing and low temperature heat capacity of disordered pyrochlore oxide Ho2Zr2O7
Authors: Sheetal  , Elghandour A , Klingeler R , Yadav C S
Published: March 2022

Spin ice materials are the model systems that have a zero-point entropy as T → 0 K, owing to the frozen disordered states. Here, we chemically alter the well-known spin ice Ho2Ti2O7 by replacing Ti sites with isovalent but larger Zr ion. Unlike the Ho2Ti2O7 which is a pyrochlore material, Ho2Zr2O7 crystallizes in disordered pyrochlore structure. We have performed detailed structural, ac magnetic susceptibility and heat capacity studies on Ho2Zr2O7 to investigate the interplay of structural disorder and frustrated interactions. The zero-field ground state exhibits large magnetic susceptibility and remains dynamic down to 300 mK without showing Pauling’s residual entropy. The dynamic state is suppressed continuously with the magnetic field and freezing transition evolves (∼10 K) at a field of ∼10 kOe. These results suggest that the alteration of chemical order and local strain in Ho2Ti2O7 prevents the development of spin ice state and provides a new material to study the geometrical frustration based on the structure.
A compact magnetic resonance system with inside-out sensor for soil moisture measurement
Authors: Wan Cai , He Wei , Guo Pan , Wu Jiamin , He Yucheng , Xu Zheng
Published: March 2022

Accurate measurement of soil moisture parameters plays a vital role in promoting agricultural production. Nuclear magnetic resonance (NMR) measuring instruments have become increasingly compact, especially in low field applications. However, NMR soil moisture measurement instruments still have problems with portability. We report on a compact NMR measuring instrument that focuses on the circuit’s design and construction. The instrument includes an inside-out sensor, NMR spectrometer, radio frequency power amplifier, low-noise preamplifier, and duplexer. They are integrated into a slim 3D-printed cylinder. The integrated NMR instrument is portable and user-friendly and can reduce the influence of nonideal factors, such as transmission line effects and electromagnetic interference. We conducted different soil moisture experiments with the prototype using Carr–Purcell–Meiboom–Gill pulse sequence to obtain the corresponding transverse relaxation time (T
2) decay curves. Then, the T
2 1D spectrum distributions were obtained by inverse Laplace transformation. Finally, the results reveal that the area of long T
2 component decreases as the soil moisture content decreases.
DIR-based models to predict weekly anatomical changes in head and neck cancer proton therapy
Authors: Zhang Ying , McGowan Holloway Stacey , Zoë Wilson Megan , Alshaikhi Jailan , Tan Wenyong , Royle Gary , Bär Esther
Published: March 2022

Objective. We proposed two anatomical models for head and neck patients to predict anatomical changes during the course of radiotherapy. Approach. Deformable image registration was used to build two anatomical models: (1) the average model (AM) simulated systematic progressive changes across the patient cohort; (2) the refined individual model (RIM) used a patient’s CT images acquired during treatment to update the prediction for each individual patient. Planning CTs and weekly CTs were used from 20 nasopharynx patients. This dataset included 15 training patients and 5 test patients. For each test patient, a spot scanning proton plan was created. Models were evaluated using CT number differences, contours, proton spot location deviations and dose distributions. Main results. If no model was used, the CT number difference between the planning CT and the repeat CT at week 6 of treatment was on average 128.9 Hounsfield Units (HU) over the test population. This can be reduced to 115.5 HU using the AM, and to 110.5 HU using the RIM3 (RIM, updated at week (3). When the predicted contours from the models were used, the average mean surface distance of parotid glands can be reduced from 1.98 (no model) to 1.16 mm (AM) and 1.19 mm (RIM3) at week 6. Using the proton spot range, the average anatomical uncertainty over the test population reduced from 4.47 ± 1.23 (no model) to 2.41 ± 1.12 mm (AM), and 1.89 ± 0.96 mm (RIM3). Based on the gamma analysis, the average gamma index over the test patients was improved from 93.87 ± 2.48 % (no model) to 96.16 ± 1.84% (RIM3) at week 6. Significance. The AM and the RIM both demonstrated the ability to predict anatomical changes during the treatment. The RIM can gradually refine the prediction of anatomical changes based on the AM. The proton beam spots provided an accurate and effective way for uncertainty evaluation.
Plasma physics and control studies planned in JT-60SA for ITER and DEMO operations and risk mitigation
Authors: Yoshida M , Giruzzi G , Aiba N , Artaud J F , Ayllon-Guerola J , Balbinot L , Beeke O , Belonohy E , Bettini P , Bin W , Bierwage A , Bolzonella T , Bonotto M , Boulbe C , Buermans J , Chernyshova M , Coda S , Coelho R , Davis S , Day C , De Tommasi G , Dibon M , Ejiri A , Falchetto G , Fassina A , Faugeras B , Figini L , Fukumoto M , Futatani S , Galazka K , Garcia J , Garcia-Muñoz M , Garzotti L , Giacomelli L , Giudicotti L , Hall S , Hayashi N , Hoa C , Honda M , Hoshino K , Iafrati M , Iantchenko A , Ide S , Iio S , Imazawa R , Inoue S , Isayama A , Joffrin E , Kamiya K , Ko Y , Kobayashi M , Kobayashi T , Kocsis G , Kovacsik A , Kurki-Suonio T , Lacroix B , Lang P , Lauber Ph , Louzguiti A , de la Luna E , Marchiori G , Mattei M , Matsuyama A , Mazzi S , Mele A , Michel F , Miyata Y , Morales J , Moreau P , Moro A , Nakano T , Nakata M , Narita E , Neu R , Nicollet S , Nocente M , Nowak S , Orsitto F P , Ostuni V , Ohtani Y , Oyama N , Pasqualotto R , Pégourié B , Perelli E , Pigatto L , Piccinni C , Pironti A , Platania P , Ploeckl B , Ricci D , Roussel P , Rubino G , Sano R , Särkimäki K , Shinohara K , Soare S , Sozzi C , Sumida S , Suzuki T , Suzuki Y , Szabolics T , Szepesi T , Takase Y , Takech M , Tamura N , Tanaka K , Tanaka H , Tardocchi M , Terakado A , Tojo H , Tokuzawa T , Torre A , Tsujii N , Tsutsui H , Ueda Y , Urano H , Valisa M , Vallar M , Vega J , Villone F , Wakatsuki T , Wauters T , Wischmeier M , Yamoto S , Zani L
Published: March 2022

A large superconducting machine, JT-60SA has been constructed to provide major contributions to the ITER program and DEMO design. For the success of the ITER project and fusion reactor, understanding and development of plasma controllability in ITER and DEMO relevant higher beta regimes are essential. JT-60SA has focused the program on the plasma controllability for scenario development and risk mitigation in ITER as well as on investigating DEMO relevant regimes. This paper summarizes the high research priorities and strategy for the JT-60SA project. Recent works on simulation studies to prepare the plasma physics and control experiments are presented, such as plasma breakdown and equilibrium controls, hybrid and steady-state scenario development, and risk mitigation techniques. Contributions of JT-60SA to ITER and DEMO have been clarified through those studies.
Validation of a desktop-type magnet providing a quasi-microgravity space in a room-temperature bore of a high-gradient trapped field magnet (HG-TFM)
Authors: Takahashi Keita , Fujishiro Hiroyuki , Ainslie Mark D
Published: March 2022

The concept of a high-gradient trapped field magnet (HG-TFM), which incorporates a hybrid system of two (RE)BaCuO superconducting bulk components with different functions, was proposed in 2021 by the authors based on the results of numerical simulations. The HG-TFM as a desktop-type magnet can be a more effective way to generate a higher magnetic field gradient product of Bz
· dBz
/dz (>−1400 T2 m−1, as calculated for a pure water), which can realize a quasi-microgravity space applicable for Space Environment Utilization on a laboratory scale. In this study, to validate the quasi-microgravity space in the HG-TFM, a prototype HG-TFM apparatus has been built using a slit-bulk TFM and stacked full-TFM (without slits) with inner diameters of 36 mm. After field-cooled magnetization from 8.60 T at 21 K, a trapped field of B
T = 8.57 T was achieved at the center (i.e. at the bottom of a room temperature bore of 25 mm diameter outside the vacuum chamber), and consequently, a maximum Bz
· dBz
/dz = −1930 T2 m−1 was obtained at the intermediate position between the slit-bulk TFM and the stacked full-TFM. Magnetic levitation was demonstrated successfully for bismuth particles and a pure water drop, which validates the quasi-microgravity environment in the HG-TFM. Based on numerical simulation results of the trapped field profile, it is concluded that the reason for the instability of the levitated targets is because of the repulsive magnetic force applied along the horizontal plane. The levitating state can be controllable, for example, by changing the operating temperature, which would allow objects to levitate statically along the central axis.
Textured concave anti-reflecting coating and convex back reflector to enhance the absorbance of amorphous Si solar cells
Authors: Taha T A , Sayed Hassan , Aly Arafa H , Elsayed Hussein A
Published: March 2022

This work provides efficient designs in each the anti-reflective coating (ARC) and back reflector for enhancing the absorption of amorphous silicon solar cells. ARC structures are designed from planar, concave, and textured concave surfaces. For the back reflector structures, we use the concepts of the photonic bandgap (PBG) structure and convex surface. The mainstay in designing the ARC is specifically depending on the presence of a gradual increase in the refractive index as the incident radiation travels from air to the cell to decrease the solar cell reflectivity. Thus, the arrangement of (SiO2/Si3N4/SiC) layers is considered in designing the proposed ARC. The theoretical formalism of this study is based on the finite element method and transfer matrix method as well. The numerical results demonstrate the cell absorption based on the different configurations of the ARC and the back reflecting mirror. The investigated results show that the solar cell absorption increases by 34.92% at 520 nm by including the planar ARC. However, significant decrements are obtained with the increase of the angle of incidence for the planar ARC. Meanwhile, the concave and textured geometries provide a perfect solution towards the increase of cell absorption with the angle of incidence, especially at wavelengths smaller than 550 nm. For wavelengths greater than 550 nm, 3-unit cells with the convex geometry represent the optimum design of the back mirror to increase the cell absorption at these wavelengths. Finally, the textured concave ARC and convex back reflector through the amorphous Si solar cell present a good candidate for significant enhancements of the cell absorption and optical generation as well.
Investigation of bi-particle states in gate-array-controlled quantum-dot systems aided by machine learning techniques
Authors: Nemnes G A , Mitran T L , Preda A T , Ghiu I , Marciu M , Manolescu A
Published: March 2022

Quantum computing architectures require an accurate and efficient description in terms of many-electron states. Recent implementations include quantum dot arrays, where the ground state of a multi q-bit system can be altered by voltages applied to the top gates. An extensive investigation concerning the spectra of the many-electron systems under multiple operation conditions set by external voltages typically requires a relatively large number of Hamiltonian diagonalizations, where the Coulomb interaction is considered in an exact manner. Instead of making exhaustive calculations using high throughput computing, we approach this problem by augmenting numerical diagonalizations with machine learning techniques designed to predict the many-electron eigenvalues and eigenfunctions. To this end, we employ and compare the results from linear regression methods such as multivariate least squares (MLS) as well as non-linear techniques based on kernel ridge regression (KRR), Gaussian process regression (GPR) and artificial neural networks (ANNs). The input feature vectors are assembled from readily available information comprised from a binary representation of the potential and the strength of the Coulomb interaction. Furthermore, employing a linear classifier, we establish a rule for detecting a singlet-triplet transition which may arise for certain potential configurations.
Optical biosensor based on a photonic crystal with a defective layer designed to determine the concentration of SARS-CoV-2 in water
Authors: Efimov I M , Vanyushkin N A , Gevorgyan A H , Golik S S
Published: March 2022

We propose a new optical biosensor based on a SiO2/Si photonic crystal with a defect layer, which can determine the concentration of SARS-CoV-2 in water by the defect mode shift. Two models of the dependence of the refractive index of the defect layer on the concentration of the pathogen in water were considered. The optimal parameters of the photonic crystal in our device were determined such as the thickness of the SiO2 and Si layers of the ideal photonic crystal of 0.720 and 0.275 μm, respectively, and the optimal thickness of the defect layer of 1.87 μm was also determined. It was also demonstrated that in the presence of absorption in the structure under study, it is much more advantageous to operate in the reflection mode compared to the transmission mode. Finally, the wavelength dependence of the defect mode on the SARS-CoV-2 concentration was obtained and the sensitivity of the sensor was determined to be 1020 nm/RIU.
Local sum uncertainty relations for angular momentum operators of bipartite permutation symmetric systems
Authors: Reena I , Karthik H S , Tej J Prabhu , Sudha  , Devi A R Usha , Rajagopal A K
Published: March 2022

We show that violation of the variance based local sum uncertainty relation (LSUR) for angular momentum operators of a bipartite system, proposed by Hofmann and Takeuchi [Phys. Rev. A
68 032103 (2003)], reflects entanglement in the equal bipartitions of an N-qubit symmetric state with even qubits. We establish the one-to-one connection with the violation of LSUR with negativity of covariance matrix [Phys. Lett. A
364 203 (2007)] of the two-qubit reduced system of a permutation symmetric N-qubit state.
Entropy per Rapidity in Pb-Pb Central Collisions using Thermal and Artificial Neural Network (ANN) Models at LHC Energies
Authors: Habashy D. M. , El-Bakry Mahmoud Y. , Scheinast Werner , Hanafy Mahmoud
Published: March 2022

The entropy per rapidity

produced in central Pb-Pb ultra-relativistic nuclear collisions at LHC energies is calculated using experimentally identified particle spectra and source radii estimated from Hanbury Brown-Twiss (HBT) correlations for particles π, k, p, Λ, Ω, and

and π, k, p, Λ, and

at

and

TeV, respectively. An artificial neural network (ANN) simulation model is used to estimate the entropy per rapidity

at the considered energies. The simulation results are compared with equivalent experimental data, and a good agreement is achieved. A mathematical equation describing the experimental data is obtained. Extrapolation of the transverse momentum spectra at

is required to calculate

; thus, we use two different fitting functions, the Tsallis distribution and hadron resonance gas (HRG) model. The success of the ANN model in describing the experimental measurements leads to the prediction of several spectra values for the mentioned particles, which may lead to further predictions in the absence of experiments.
New puzzle in charmonium decays *
Authors: Wang Hongpeng , Yuan Chang-Zheng
Published: March 2022

By analyzing existing data on pseudoscalar charmonium decays, we obtain the ratio of the branching fractions of

and

decays into ten different final states with light hadrons. For the first time, we test the two existing theoretical predictions of these decays and find that the experimental data are significantly different from both of them. The lack of observation of any decay mode with higher rate in

than in

decays suggests very unusual decay dynamics in pseudoscalar charmonium decays to be identified. We also report the first model-independent evaluation of the partial width of

(

keV) and improve determination of that of

(

keV). The latter shows a tension with the most recent lattice QCD calculation.
Sideways forces on asymmetric tokamak walls during plasma disruptions
Authors: Yanovskiy V. , Isernia N. , Pustovitov V.D. , Villone F.
Published: March 2022

In the quarter-century since the danger of sideways force on tokamak walls during disruptions was first recognized, substantial progress has been made in understanding the connection between plasma kink and the force. Less is known, however, about the effect of the wall asymmetry on force generation. Here, we explore how irregularly situated ports lead to large sideways forces even for a symmetric driver such as a typical current quench. Further, we compare the effectiveness of both mechanisms.
Application of quasi-rotation surface segments in architectural prototyping
Authors: Beglov I A , Rustamyan V V , Verbitskiy R A
Published: March 2022

The present paper details an approach to modeling of quasi-rotation surface segments with pre-defined conditions. The desired surfaces and their segments are formed parametrically through Maple computer algebra system. Various analytical approaches to trimming of the excessive parts of quasi-rotation surfaces are indicated. Geometric modeling is performed with use of a previously developed algorithm. An example illustrating the initial stage of design of an overpass between two separate buildings is provided. The design objective contains the basic geometric parameters of the desired architectural element. Three control models were created with the same initial parameters through basic CAD software methods. All of the constructed models are thin-walled. Mechanical properties of the scale 3D models of the target element were compared in equal conditions by means of CAD software. The prototype created through the use of a quasi-rotation surface segment was the most resistant to load. The paper also features a rendered concept of a complex of three towers connected with three overpasses. The acquired results allow us to conclude that quasi-rotation is an effective method of formation of models of architectural elements.