bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aseasonal and short life cycles of the protandrous hermaphrodite blue threadfin (Eleutheronema tetradactylum) in a near-equatorial tropical region
Authors: Ogino Yoshimi , Kongasa Wirot , Furumitsu Keisuke , Kume Gen , Yamaguchi Atsuko 
Published: March 2023

Context Eleutheronema tetradactylum is exploited throughout its distribution in the Indo–West Pacific region. However, there is a lack of data on its life cycle in near-equatorial regions and the northern hemisphere. Aim To investigate the age, growth, sex change and reproduction of Eleutheronema tetradactylum in southern Thailand. Methods Analysis of length, otolith and gonad data of 449 fish. Key results Contrary to findings from regions at higher latitudes, otoliths did not show seasonal increment formation. Instead, with the exception of large individuals, daily increments were distinguishable. Within the age range of 69–341 days, growth was linear, with results indicating a total length of 430 mm (69% of maximum length) at 1 year. The youngest mature male was 137 days old. Moreover, the length at which half the individuals changed from male to female was 376 mm, corresponding to 282 days. The gonadosomatic index indicated no specific spawning season, and the hatch-date calculations indicated year-round hatching. Conclusions Eleutheronema tetradactylum inhabiting near-equatorial regions is characterised by rapid population turnover compared with populations of higher latitudes. Implications Our findings indicated life-history variability, including seasonality loss in near-equatorial habitats, of an important coastal fish. This information is important for species conservation.
The EFF as a ‘gateway party’? Briefing based on data from the 2021 South African local government elections
Authors: Bekker Martin 
Published: March 2023

SUMMARY
This briefing offers three contributions concerning the voter profile of the Economic Freedom Fighters (EFF), as witnessed at the 2021 elections in South Africa. The first is that the party’s support base is relatively well educated (compared to the ruling African National Congress). Second, well over 10% of party support comes from relatively high earners, as measured by income levels. Finally, EFF support appears notably ‘fluid’, as indicated by voters switching support to the EFF (mostly from the ANC) and away from the EFF (mostly towards smaller parties), ultimately suggesting an image of the EFF as a ‘gateway party’.
The Landau–Zener formula made simple
Authors: Glasbrenner Eric P , Schleich Wolfgang P 
Published: March 2023

Abstract
We employ the Markov approximation and the well-known Fresnel-integral to derive in ‘one-line’ the familiar expression for the Landau–Zener transition probability. Moreover, we provide numerical as well as analytical justifications for our approach, and identify three characteristic motions of the probability amplitude in the complex plane.
Realization of a supersolid phase in a two-channel model
Authors: Wei Qin , Xu Junjun 
Published: March 2023

Abstract
We construct a two-channel model based on the one-dimensional extended Bose–Hubbard model, by including a second channel of free bosons. We use the mean-field theory to map the system to a reduced single-channel one and solve this system by means of the density matrix renormalization group method. We find the region where the superfluid and density-wave orders coexist which signals a supersolid state. Our theory can be realized experimentally with state-dependent optical lattices.
Low-energy solar neutrino detection utilizing advanced germanium detectors
Authors: Bhattarai S , Mei D-M , Raut M S 
Published: March 2023

Abstract
We explore the possibility to use advanced germanium (Ge) detectors as a low-energy solar neutrino observatory by means of neutrino-nucleus elastic scattering. A Ge detector utilizing internal charge amplification for the charge carriers created by the ionization of impurities is a novel technology with experimental sensitivity for detecting low-energy solar neutrinos. Ge internal charge amplification (GeICA) detectors will amplify the charge carriers induced by neutrino interacting with Ge atoms through the emission of phonons. It is those phonons that will create charge carriers through the ionization of impurities to achieve an extremely low energy threshold of ∼0.01 eV. We demonstrate the phonon absorption, excitation, and ionization probability of impurities in a Ge detector with impurity levels of 3 × 1010 cm−3, 9 × 1010 cm−3, and 2 × 1011 cm−3. We present the sensitivity of such a Ge experiment for detecting solar neutrinos in the low-energy region. We show that, if GeICA technology becomes available, then a new opportunity arises to observe pp and 7Be solar neutrinos. Such a novel detector with only 1 kg of high-purity Ge will give ∼10 events per year for pp neutrinos and ∼5 events per year for 7Be neutrinos with a detection energy threshold of 0.01 eV.
Terahertz amplification and lasing by using transverse electric modes in a two-layer-graphene-dielectric waveguide structure with direct current
Authors: Moiseenko I M , Popov V V , Fateev D V 
Published: March 2023

Abstract
We study for the first time the interaction between the waveguide modes of graphene structure and freely propagating terahertz (THz) electromagnetic waves (this interaction takes place within the light cone). We revealed a new and rather unexpected physical phenomenon by showing that freely incident THz electromagnetic waves can resonate with the surface transverse electric (TE) modes of the graphene waveguide in virtue of these modes having their dispersions in the vicinity of the light cone. The dispersion and amplification of surface TE modes in a dielectric waveguide covered with two graphene layers biased by direct current (DC), as well the amplification and lasing of incident THz wave by excitation of TE mode resonances, are investigated. The DC flows perpendicular to the direction of the surface wave propagation and creates the capacitive complex conductivity of graphene at THz frequencies, which is necessary for the existence of surface TE modes in graphene. The real part of graphene conductivity can be negative at THz frequencies due to DC in graphene which leads to amplification and lasing of THz radiation. Such structure can be of great practical importance because an external THz wave can be amplified or generated in lasing process without using special coupling elements commonly needed for ensuring the interaction between external THz wave and surface waveguide modes. The use of a two-layer graphene structure makes it possible to reduce the charge–carrier drift velocity required for reaching the lasing threshold at those resonances, as compared to a structure with a single graphene layer.
A new convolutional neural network-based framework and data construction method for structural damage identification considering sensor placement
Authors: Yang Jianhui , Peng Zhenrui 
Published: March 2023

Abstract
In the application of data driven structural damage identification (SDI) based on supervised deep learning technology, valid data demarcation is the foundation; a convolutional neural network model with learning ability and capability of processing rich signal information is the core. Based on this understanding, this work makes three contributions: Firstly, the structural damage location and severity are jointly demarcated, and the SDI problem is transformed into a multi-classification task. Secondly, a 3D signal processing convolutional neural networks (3DS-CNN) is designed with an attempt to identify the complex and slight damages using the most basic network structure. Thirdly, a ‘major and subsidiary’ data construction (MSDC) method integrating the key intrinsic mode function is proposed to construct 3D data. Then the proposed schemes are verified by two different structures. The results show that the 3DS-CNN has excellent damage identification ability for small-size data with noise pollution. MSDC method can enrich the feature information of the damage signals and help the network with deep feature excavation, even if the vibration signals are heavily polluted. Going one step further, the impact of sensor placement is discussed, and it is found that when external excitation is obvious, better SDI accuracy can be achieved even using a single sensor signal with slight noise. When the noise interference is obvious, the generalization ability and noise robustness of the network can be enhanced by optimizing sensor placement. In this case, the sensor placement criteria and the sensitive nodes of the structure should be comprehensively and carefully considered to avoid mutual ‘coupling’ interference of data between sensors.
Improving the intrinsic activity of ultrathin 2D–2D heterostructures by bridge-bonded Ni–O–Ti ligands for efficient oxygen evolution
Authors: Xu Chenhui , Xiong Furong , Wang Yao , Nai Jianwei , Zhang Wang 
Published: March 2023

Abstract
The integration of ultrathin two-dimensional (2D) semiconductors with other conductive 2D materials to form hybrid electrocatalysts with abundant heterointerfaces can enhance the electrocatalytic activity by facilitating interfacial charge transfer. However, the hybrid electrocatalysts with weak interfacial bonding have limited effect on the electrocatalytic performance because the intrinsic activity of interfacial sites cannot be altered by weak interfacial interactions. As a proof-of-concept, we design ultrathin 2D–2D heterostructures with bridge-bonded Ni–O–Ti ligands based on single-layered Ti3C2T
x
MXene and metal hydroxides, and further reveal the structure-activity correlation between interfacial bonding and electrocatalytic oxygen evolution reaction by combining theoretical and experimental studies. Density functional theory calculations reveal the modulation of the electronic structure of interfacial metal sites after the formation of bridged interfacial Ni–O–Ti bonding. Compared with the hydrogen-bond-linked heterostructure, the ultrathin 2D–2D heterostructure with bridge-bonded Ni–O–Ti ligands shows enhanced intrinsic activity and stability towards electrocatalytic oxygen evolution with a very low overpotential of 205 mV at 10 mA cm−2 and the long-term durability. This work provides a new understanding and approach for the design and development of 2D hybrid catalysts with highly efficient electrocatalytic activity.
Orbital stability and instability of periodic wave solutions for

ϕ4n

-models
Authors: Chen Gong , Palacios José M 
Published: March 2023

Abstract
In this work we study the orbital stability/instability in the energy space of a specific family of periodic wave solutions of the general

ϕ

4
n

-model for all

n
∈

N

. This family of periodic solutions are orbiting around the origin in the corresponding phase portrait and, in the standing case, are related (in a proper sense) with the aperiodic Kink solution that connect the states

−

v
2

with

v
2

. In the traveling case, we prove the orbital instability in the whole energy space for all

n
∈

N

, while in the standing case we prove that, under some additional parity assumptions, these solutions are orbitally stable for all

n
∈

N

. Furthermore, as a by-product of our analysis, we are able to extend the main result in (de Loreno and Natali 2020 arXiv:2006.01305) (given for a different family of equations) to traveling wave solutions in the whole space, for all

n
∈

N

.
Evolution of cooperation under the coexistence of imitation and aspiration dynamics in structured populations
Authors: Arefin Md Rajib , Tatsukawa Yuichi , Tanimoto Jun 
Published: March 2023

Abstract
Imitation and aspiration learning rules are frequently observed in humans and animals. The former is an act of copying other’s action, whereas the latter is characterized by the self-evaluation. Here we study the coexistence of these learning mechanisms in structured populations. Both rules have been combined focusing on two different scenarios: (I) adoption of either update rule with a certain probability, and (II) grouping the entire population according to the update rules. We present two pair approximation models, illustrating both scenarios, which yield a nice agreement—under weak selection—with that of agent-based simulations. For weak selection and large population size, we find that the condition for cooperation to dominate defection is similar in both heterogeneous and homogeneous update rules. We examine several variants of the mixed model such as time-evolving aspirations alongside strategies and the coevolution of strategies and update rules. In the former case, our simulation reveals that Prisoner’s dilemma and, in some cases, Stag-hunt experience overall less aspiration levels compared to other games such as Chicken or Trivial. The coevolution of strategies and update rules demonstrates a better cooperation, in contrast to the fixed update rule case, exhibiting the possibility of asymptotic coexistence of both learning mechanisms.
‘I can now detect and rectify my error.’ New generation ninth-grade learner’s problem-solving skills during experiments in physics through metacognitive brainstorming strategy
Authors: Uddin Md Jamal , Panda Bhujendra Nath , Agarwal Prakash Chandra 
Published: March 2023

Abstract
Enhancing the problem-solving skills of learners belonging to socio-economically disadvantaged groups is a great concern in general and particularly in the Indian context. Problem-solving skills are the most important skills of the 21st century for all learners to acquire necessary competencies. The main purpose of this work is to investigate the effect of metacognitive brainstorming strategy, gender, and residential areas, and their various interactions on problem-solving skills in physics for ninth-grade learners who belong to socio-economically marginalised groups. The pre-test–post-test, quasi-experimental design was applied to 107 learners from two government-sponsored schools of the same nature located in Kolkata, West Bengal, India. The 55 learners in the experimental group were given intervention through a metacognitive brainstorming strategy, whereas the 52 learners in the control group were taught the same lessons by simply using the conventional method. Self-developed and standard problem-solving skills test with a reliability of 0.89 and validity of 0.94 were employed on them as pre-test and post-test instances. The correlated t-test, independent samples t-test, and 2 × 2 factorial design analysis of covariance were applied for data analysis through Statistical Package for Social Science. The results revealed that the brainstorming instructional strategy had a huge effect on problem-solving skills due to its large effect size value (2.23 > 1.2). Moreover, the problem-solving skills of learners in physics were found to be independent of gender and residential areas, and also of their interaction with the treatment strategy, when the pre-problem-solving skill was taken as a covariate.
Implications of using the clinical target distribution as voxel-weights in radiation therapy optimization
Authors: Bengtsson Ivar , Forsgren Anders , Fredriksson Albin 
Published: March 2023

Abstract

Objective. Delineating and planning with respect to regions suspected to contain microscopic tumor cells is an inherently uncertain task in radiotherapy. The recently proposed clinical target distribution (CTD) is an alternative to the conventional clinical target volume (CTV), with initial promise. Previously, using the CTD in planning has primarily been evaluated in comparison to a conventionally defined CTV. We propose to compare the CTD approach against CTV margins of various sizes, dependent on the threshold at which the tumor infiltration probability is considered relevant. Approach. First, a theoretical framework is presented, concerned with optimizing the trade-off between the probability of sufficient target coverage and the penalties associated with high dose. From this framework we derive conventional CTV-based planning and contrast it with the CTD approach. The approaches are contextualized further by comparison with established methods for managing geometric uncertainties. Second, for both one- and three-dimensional phantoms, we compare a set of CTD plans created by varying the target objective function weight against a set of plans created by varying both the target weight and the CTV margin size. Main results. The results show that CTD-based planning gives slightly inefficient trade-offs between the evaluation criteria for a case in which near-minimum target dose is the highest priority. However, in a case when sparing a proximal organ at risk is critical, the CTD is better at maintaining sufficiently high dose toward the center of the target. Significance. We conclude that CTD-based planning is a computationally efficient method for planning with respect to delineation uncertainties, but that the inevitable effects on the dose distribution should not be disregarded.
Benefits of using removable filters in dual-layer flat panel detectors
Authors: Cai Emily Y , De Caro Christian , Treb Kevin , Li Ke 
Published: March 2023

Abstract

Objective. Existing dual-layer flat panel detectors (DL-FPDs) use a thin scintillator layer to preferentially detect low-energy x-rays, followed by a permanent Cu filter to absorb residual low-energy x-rays, and finally, a thicker scintillator layer to preferentially detect high-energy x-rays. The image outputs of the two scintillator layers can be jointly processed for dual-energy (DE) planar and cone-beam CT imaging. In clinical practice, a given FPD is often used for not only DE imaging but also routine single-energy (SE) imaging. With the permanent Cu layer, the total x-ray absorption is unsatisfactory for SE imaging since more than 30% of x-rays can be lost in the Cu layer. The purpose of this work was to demonstrate the benefits of using a removable filter material in DL-FPDs for SE and DE imaging applications. Approach. The proposed detector contains a removable filter between the two scintillator layers. The filter can be either a chamber filled with a liquid high-Z
eff material or a removable solid filter. When DE imaging is not clinically indicated, the DL-FPD can switch to a high-efficiency SE imaging mode by retracting the filter from the inter-scintillator space. For commonly available filter materials (iodine, gadolinium, and Cu), their optimal area densities were theoretically calculated for both water-bone decomposition and water-iodine decomposition DE imaging tasks. Preliminary experimental studies were also performed to compare the SE performance of the proposed DL-FPD with the existing DL-FPD with the permanent Cu filter and study the stability of the liquid filter on a rotating gantry. Main results. The optimal filter material was found to be an iodine solution (approximately 375 mg cm−2). With this liquid filter in place, the proposed DL-FPD has equivalent or better DE imaging performance compared with the existing DL-FPD with the Cu filter. When the filter is removed from the inter-scintillator space for SE imaging, the total x-ray absorption efficiency of the proposed DL-FPD ranges from 73% (100 kVp) to 54% (140 kVp), compared with 51% (100 kVp) to 41% (140 kVp) for the existing DL-FPD with a permanent 1 mm Cu filter. Significance. The removable filter provides a boost to the total x-ray absorption efficiency of DL-FPDs for SE imaging without compromising DE imaging. This can facilitate the adoption of DL-FPDs in clinical x-ray imaging systems that usually perform more SE imaging procedures than DE imaging series.
Micro-CT imaging of multiple K-edge elements using GaAs and CdTe photon counting detectors
Authors: Allphin A J , Clark D P , Thuering T , Bhandari P , Ghaghada K B , Badea C T 
Published: March 2023

Abstract

Objective. To evaluate the performance of two photon-counting (PC) detectors based on different detector materials, gallium arsenide (GaAs) and cadmium telluride (CdTe), for PC micro-CT imaging of phantoms with multiple contrast materials. Another objective is to determine if combining these two detectors in the same micro-CT system can offer higher spectral performance and significant artifact reduction compared to a single detector system. Approach. We have constructed a dual-detector, micro-CT system equipped with two PCDs based on different detector materials: gallium arsenide (GaAs) and cadmium telluride (CdTe). We demonstrate the performance of these detectors for PC micro-CT imaging of phantoms with up to 5 contrast materials with K-edges spread across the x-ray spectrum ranging from iodine with a K-edge at 33.2 keV to bismuth with a K-edge at 90.5 keV. We also demonstrate the use of our system to image a mouse prepared with both iodine and bismuth contrast agents to target different biological systems. Main results. When using the same dose and scan parameters, GaAs shows increased low energy (<50 keV) spectral sensitivity and specificity compared to CdTe. However, GaAs performance at high energies suffers from spectral artifacts and has comparatively low photon counts indicating wasted radiation dose. We demonstrate that combining a GaAs-based and a CdTe-based PC detector in the same micro-CT system offers higher spectral performance and significant artifact reduction compared to a single detector system. Significance. More accurate PC micro-CT using a GaAs PCD alone or in combination with a CdTe PCD could serve for developing new contrast agents such as nanoparticles that show promise in the developing field of theranostics (therapy and diagnostics).
The internal transport barrier formation on EAST tokamak during the fishbone instability
Authors: Wang Siqi , Cai Huishan , Chen Xiang , Li Ding 
Published: March 2023

Abstract
The internal transport barrier (ITB) which is related to the fishbone instability has been observed on the Experimental Advanced Superconducting Tokamak (EAST) in ELMy H-mode discharges. An interpretation of the formation of the ITB on EAST tokamak is provided, based on both analytical and numerical calculations. The fishbone instability induces the redistribution of fast ions and leads to the accumulation of fast ions in a local region where the ITB is going to appear. Correspondingly, the gradients of fast ions are enhanced, where the ion temperature gradient (ITG) mode exists. Fast ions can interact with the ITG mode through the dilution, Shafranov shift and wave-particle resonance mechanisms. It is found that the ITG mode is stabilized by fast ions and the stabilizing effects are determined mainly by the density, temperature and their gradients of fast ions. The enhanced density and temperature gradients of fast ions lead to a stronger stabilizing effect on ITG mode. Compared with the stabilizing effect before the appearance of fishbone instability, the stabilization on ITG mode is enhanced after the fishbone instability, which is beneficial to the formation of the ITB.