bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acoustic metamaterials with zero-index behaviors and sound attenuation
Authors: Wu Guanghua , Ke Yibo , Zhang Lin , Tao Meng 
Published: April 2022

Abstract
The Helmholtz resonator suffers from needing to be excessively large to manipulate low-frequency sound waves and supports only monopolar resonance. To solve these problems, combining the space-coiling concept and multiunit lumped coupling concept, a new metamaterial is proposed, that exhibits an extraordinary acoustic response related to multiple resonant patterns in the low-frequency regime. At the upper and lower edges of the bandgap, acoustic wavefront reshaping is achieved. Considering the shift of the modulation frequency and the mismatched impedance, an alternative and simple strategy is presented to achieve acoustic cloaking. Furthermore, by flexibly varying the distances between the metamaterial plates and inserted obstacles, acoustic cloaking independent of the boundary conditions of the inserted obstacles is achieved. Finally, based on the negative acoustic response of the structure, acoustic barriers capable of air ventilation and sound attenuation simultaneously are achieved and verified by experimental results.
First-order differential filtering spectrum division method and information fusion multi-scale network for fault diagnosis of bearings under different loads
Authors: Wang Junyuan , Han Fei , Li Yanfeng , Wang Zhijian , Du Wenhua 
Published: April 2022

Abstract
In recent years, data-driven intelligent diagnosis methods have been widely applied in the field of bearing fault diagnosis. However, these methods involve some expert experience and knowledge, and cannot accurately mine bearing fault characteristics under different loads. To solve this problem, this paper proposes a first-order differential filtering spectrum division (FDFSD) method and an information fusion multi-scale network (IFMSNet) to realize bearing fault diagnosis under different working conditions. First of all, the proposed spectrum division method based on the first-order differential filtering, the first-order differential processing of time domain signals, and the introduction of triangular filter, reclassify the spectrum features, highlight feature information, can accurately extract bearing fault features. Secondly, a new multi-scale network model of information fusion is constructed in this paper. Convolution kernels of different sizes are used to extract fault features of bearings of different scales, and information fusion is carried out to identify bearing working conditions and realize intelligent diagnosis of bearings under different loads. Finally, in order to verify the effectiveness and accuracy of the proposed method, it is verified on a variety of bearing experimental data sets. The results show that the average prediction accuracy of the proposed method is 99.11% and 97.74%, respectively. Compared with the proposed three single-scale network, K-nearest neighbor, Naive Bayes, support vector machine and random forest methods, the proposed method has more advantages in bearing intelligent diagnosis under different loads.
Tailoring the critical temperature of Ca/K-1144 superconductors: the effect of aliovalent substitution on tetragonality
Authors: Masi A , Duchenko A , Celentano G , Varsano F 
Published: April 2022

Abstract
Among the iron-based superconductors, the so-called 1144 family has, in recent years, attracted significant interest due to its stoichiometric nature, with materials robust towards chemical inhomogeneities and characterized by a well-defined critical temperature. The most studied 1144 compounds are characterized by the A1AE1Fe4As4 chemical composition, where A and AE constitute an appropriate combination of alkaline and alkaline-earth metals, respectively. The 1144 structure is in fact formed only when the A and AE elements respect specific requirements in terms of relative size and parent compound structure. The stoichiometric aspect, one of their strong points, has represented, however, up to today a restriction, limiting the conceptualization of 1144 structures to quaternary compounds. In this work, we demonstrate that to obtain the 1144 crystalline phase it may be sufficient to maintain a 1:1 ratio between ions of different size that intercalate the Fe-As planes, and that in selected conditions an opportunely tailored cation substitution is possible. Using a simple mechanochemically assisted synthesis route 1144 compounds where Ca is substituted by Na, K by Ba, and both simultaneously, are obtained. We demonstrate that the critical temperature of doped compounds is not simply related to the substitution amount or to the resulting Fe valence. We show that the superconducting transition is in fact linked to the structural distortion induced by the chemical composition variation: by tailoring the chemical composition we obtain doubly substituted samples—with substitution levels up to 20%—characterized by a tetragonality ratio c/a similar to the pristine compound and critical temperatures of approximately 34 K.
Manipulating photons in a way like an optical tweezer
Authors: Wu Jun-Fang , Chen Jia-Hui , Li Chao 
Published: April 2022

Abstract
Arbitrary control of photon flow is of fundamental significance in many applications of light. Here, we propose a new approach that can trap, store, and move the signal photons to arbitrary desired place, just like what optical tweezers do on micro particles. In addition, the trapped photons can also be released at a given direction. The mechanism is based on an ultrahigh-Q nanocavity formed by two dynamically-generated potential barriers in a photonic crystal (PC) waveguide. Different from the traditional fixed ultrahigh-Q nanocavities, this new-type cavity can be formed instantaneously at any moment and any position in a PC waveguide, and is completely movable while keeps ultrahigh Q factor simultaneously. These novel features make controlling the flow of light like an optical tweezer possible, and open up new opportunities for dynamic light–matter interactions and on-chip optical signal processing.
Scalarized black holes
in teleparallel gravity
Authors: Bahamonde Sebastian , Ducobu Ludovic , Pfeifer Christian 
Published: April 2022

Abstract
Black holes play a crucial role in the understanding of the gravitational interaction. Through the direct observation of the shadow of a black hole by the event horizon telescope and the detection of gravitational waves of merging black holes we now start to have direct access to their properties and behaviour, which means the properties and behaviour of gravity. This further raised the demand for models to compare with those observations.
In this respect, an important question regarding black holes properties is to know if they can support “hairs”. While this is famously forbidden in general relativity, in particular for scalar fields, by the so-called no-hair theorems, hairy black holes have been shown to exist in several class of scalar-tensor theories of gravity.
In this article we investigate the existence of scalarized black holes in scalar-torsion theories of gravity.
On one hand, we find exact solutions for certain choices of couplings between a scalar field and the torsion tensor of a teleparallel connection and certain scalar field potentials, and thus proof the existence of scalarized black holes in these theories.
On the other hand, we show that it is possible to establish no-scalar-hair theorems similar to what is known in general relativity for other choices of these functions.
Simulations on edge localized modes mitigation with impurity seeding in the HL-2A tokamak
Authors: Zhu Yiren , Xiao Guoliang , Zou Xiaolan , Zhong Wulyu , Li Jiaxian , Li Zhengji , Xue Miao , Liang Anshu , Tong Ruihai , Yuan Boda , Zou Yunpeng , Zhang Yipo , Xu Min , HL-2A Team  
Published: April 2022

Abstract
Impurity seeding has been confirmed to be a potential way for edge localized modes (ELMs) to be mitigated in tokamaks. This paper mainly combines the integrated equilibria reconstruction framework and edge simulation codes such as BOUT++ to dive deeper into the mechanism of the ELM mitigation by impurity injection. On the one hand, impurity injection changes the pedestal pressure and current profiles that are closely related to ELM activities. The nonlinear simulation result shows that ELM size decreases by a factor of 2 to 4 when the current exceeds a threshold after impurity injection. On the other hand, the decrease of E
r shear is supposed to cause a larger ELM size for a less stabilized effect. However, ELMs are mitigated with smaller E
r shear as observed in the HL-2A experiment. This indicates that changes in the profiles of pressure gradient and hence the current density may play a more important role than E
r shear in this ELM mitigation process. In contrast to the high n modes destabilized by the pellet pacing, metallic impurity seeding leads to more unstable low n modes. The simulation results indicate that the combination of changes in pressure/current and E
r shear is a plausible explanation for the ELM mitigation by metallic impurity seeding.
Magnetic reconnection rate during sawtooth crashes in ASDEX Upgrade
Authors: Samoylov O. , Igochine V. , Yu Q. , Zohm H. , the ASDEX Upgrade Team  
Published: April 2022

Abstract
The radial velocity of the plasma core during the sawtooth crashes has been measured for the first time with electron cyclotron emission imaging diagnostic. The measurements have been compared with nonlinear two-fluid simulation. The comparison reveals good qualitative and quantitative agreement, which indicates that two-fluid effects (inertia and pressure gradient of electrons) are sufficient for the correct prediction of the experimental results. Contrarily, the crash time of the Kadomtsev model, which is based on a single-fluid picture of magnetic reconnection, disagrees with the experimental results.
GeMSE: a low-background facility for gamma-spectrometry at moderate rock overburden
Authors: Ramírez García D. , Baur D. , Grigat J. , Hofmann B.A. , Lindemann S. , Masson D. , Schumann M. , von Sivers M. , Toschi F. 
Published: April 2022

Abstract
The GeMSE (Germanium Material and meteorite Screening
Experiment) facility operates a low-background HPGe crystal in an
underground laboratory with a moderate rock overburden of
620 m.w.e. in Switzerland. It has been optimized for continuous
remote operation. A multi-layer passive shielding, a muon veto, and
a boil-off nitrogen purge line inside the measurement cavity
minimize the instrument's background rate, which decreased by 33%
to (164 ± 2) counts/day (100 – 2700 keV) after five years of
underground operation. This agrees with the prediction based on the
expected decay of short-lived isotopes. A fit to the known
background components, modeled via a precise simulation of the
detector, shows that the GeMSE background is now muon-dominated. We
also present updates towards a more accurate detection efficiency
calculation for the screened samples: the thickness of the crystal's
outer dead-layer is precisely determined and the efficiency can now
be easily calculated for any sample geometry. The advantage of this
feature is showcased via the determination of the 40K content
in the screening of a complex-shaped object: a banana.
R&D of ultra-fast 8 × 8 anodes MCP-PMT
Authors: Wu Q. , Cao Y. , Huang G. , Hua Z. , Jin M. , Jin Z. , Li D. , Li K. , Liu S. , Ma L. , Qian S. , Ren L. , Si S. , Sun J. , Wang X. , Wang Y. , Yan M. , Zhang H. , Zhu Y. 
Published: April 2022

Abstract
Cooperating with the North Night Vision Science & Technology
(Nanjing) Research Institute Co. Ltd, Institute of High Energy of
Physics in China is developing a 2-inch square shape 8 × 8
anodes micro-channel-plate photomultiplier tube (MCP-PMT) with a
time resolution of picosecond level. It has a
40 × 40 mm2 bi-alkali photocathode with a peak quantum
efficiency (QE) of about 22% around a wavelength of 410 nm. With
the chevron MCP stack, the MCP-PMT can reach a gain of over 106
under a working voltage of 1500 V. The typical output waveform has
an amplitude of 64 mV and a rise time of 334 ps. Due to the
well-designed structure of the MCP-PMT, the transit time spread
(TTS) for the middle anode can reach 36 ps when working at single
photon mode. To evaluate the performance uniformity of the
8× 8 anodes MCP-PMT, ten anodes which constitutes the
smallest repetition unit of the anode array are chosen and
tested. The average transit time spread (TTS) for the 64 anodes is
44.1 ± 2.0 ps.
Projecting future nitrogen inputs: are we making the right assumptions?
Authors: Vishwakarma Srishti , Zhang Xin , Mueller Nathaniel D 
Published: April 2022

Abstract
Global use of reactive nitrogen (N) has increased over the past century to meet growing food and biofuel demand, while contributing to substantial environmental impacts. Addressing continued N management challenges requires anticipating pathways of future N use. Several studies in the scientific literature have projected future N inputs for crop production under a business-as-usual scenario. However, it remains unclear how using yield response functions to characterize a given level of technology and management practices (TMP) will alter the projections when using a consistent dataset. In this study, to project N inputs to 2050, we developed and tested three approaches, namely ‘Same nitrogen use efficiency (NUE)’, ‘Same TMP’, and ‘Improving TMP’. We found the approach that considers diminishing returns in yield response functions (‘Same TMP’) resulted in 268 Tg N yr−1 of N inputs, which was 61 and 48 Tg N yr−1 higher than when keeping NUE at the current level with and without considering changes in crop mix, respectively. If TMP continue to evolve at the pace of past five decades, projected N inputs reduce to 204 Tg N yr−1, a value that is still 59 Tg N yr−1 higher than the inputs in the baseline year 2006. Overall, our results suggest that assuming a constant NUE may be too optimistic in projecting N inputs, and the full range of projection assumptions need to be carefully explored when investigating future N budgets.
Every drop matters: combining population-based and satellite data to investigate the link between lifetime rainfall exposure and chronic undernutrition in children under five years in rural Burkina Faso
Authors: Yeboah Edmund , Kuunibe Naasegnibe , Mank Isabel , Parisi Diletta , Bonnet Emmanuel , Lohmann Julia , Hamadou Saidou , Picbougoum Bernadette T , Belesova Kristine , Sauerborn Rainer , Baernighausen Till , Danquah Ina , De Allegri Manuela 
Published: April 2022

Abstract
Climate change is projected to induce extreme and irregular rainfall patterns in the West African Sahel region, affecting household food security and income. Children are among the worst affected population groups. Previous studies focusing on rainfall irregularities in specified periods have revealed how child health and nutritional status are impacted, especially in rural settings. However, the aggregated effect of rainfall over a lifetime on chronic child undernutrition remains poorly understood. We conducted a multilevel regression using a 2017 household survey from rural Burkina Faso containing 12 919 under-five-year-old children and their corresponding household rainfall data. The rainfall data originated from the Climate Hazards Infrared Precipitation with Stations monthly dataset with a native resolution of 4.8 km (0.05°). We show that an increase in rainfall below 75 mm monthly average tends to produce poor nutritional outcomes (regression coefficient = −0.11***; 95% CI = −0.13, −0.10; p < 0.001) in rural Burkina Faso children. We found a consistent negative relationship between different sex and household wealth groups, but not age groups. Vulnerable younger children were more affected by the adverse effects of increased rainfall, while older children seemed to handle it better. Our methodological approach tracing the impact of rainfall over children’s lifetimes makes a meaningful contribution to the portfolio of tools for studying the complex relationship between climate change and health outcomes. Our work confirms that rainfall is a risk factor for chronic child undernutrition, highlighting the need for adaptation strategies that boost household and community resilience to counteract the harmful impacts of climate change on child nutritional status.
Evidence of vapor shielding effect on heat flux loaded on flowing liquid lithium limiter in EAST
Authors: LI Chenglong , ZUO Guizhong , MANIGI R , TRITZ K , ANDRUCZYK D , ZHANG Bin , LIANG Ruirong , OLIVER D , SUN Zhen , XU Wei , MENG Xiancai , HUANG Ming , TANG Zhongliang , GAO Binfu , YAN Ning , HU Jiansheng 
Published: April 2022

Abstract
A lithium (Li) vapour layer was formed around a flowing liquid Li limiter to shield against the plasma incident power and reduce limiter heat flux in the EAST tokamak. The results revealed that after a plasma operation of a few seconds, the layer became clear, which indicated a strong Li emission with a decrease in the limiter surface temperature. This emission resulted in a dense vapour around the limiter, and Li ions moved along the magnetic field to form a green shielding layer on the limiter. The plasma heat flux loaded on the limiter, measured by the probe installed on the limiter, was approximately 52% lower than that detected by a fast-reciprocating probe at the same radial position without the limiter in EAST. Additionally, approximately 42% of the parallel heat flux was dissipated directly with the enhanced Li radiation in the discharge with the liquid metal infused trenches (LIMIT) limiter. This observation revealed that the Li vapour layer exhibited an excellent shielding effect to liquid Li on plasma heat flux, which is a possible benefit of liquid-plasma-facing components in future fusion devices.
Radiation shielding design of the CFETR polarimeter interferometer and CO2 dispersion interferometer
Authors: HONG Bo , LAN Changlin , PAN Xiaodong , XU Chao , LIU Haiqing 
Published: April 2022

Abstract
A three-wave based laser polarimeter/interferometer and a CO2 laser dispersion interferometer are used to determine the electron and current density profiles on a Chinese fusion engineering test reactor (CFETR). Radiation shielding is designed for the combination of polarimeter/interferometer and CO2 dispersion interferometer. Furthermore, neutronics models of the two systems are developed based on the engineering-integrated design of CFETR polarimeter/interferometer and CO2 dispersion interferometer and the major material components of CFETR. The polarimeter/interferometer and CO2 dispersion interferometer’s neutron and photon transport simulations were performed using the Monte Carlo neutral transport code to determine the energy deposition and neutron energy spectrum of the optical mirrors. The energy depositions of the first mirrors on the polarimeter/interferometer are reduced by three orders with the whole shielding. Since the mirrors of CO2 dispersion interferometer are very close to the diagnostic first wall, shielding space is limited and the CO2 dispersion interferometer energy deposition is higher than that of the polarimeter/interferometer. The dose rate after shutdown 106 s in the back-drawer structure has been estimated to be 83 μSv h−1 when the radiation shield is filled in the diagnostic shielding modules, which is below the design threshold of 100 μSv h−1. Radiation shielding design plays a key role in successfully applying polarimeter/interferometer and CO2 dispersive interferometer in CFETR.
Effects of three typical grass cultivation patterns on the community structure of soil mites in rocky desertification control area, Guizhou, China
∗∗
Authors: Wei Qiang , Zhou Yuanyuan , Xiao Niejia , Huang Ju , Xiao Hua , Chen Hu 
Published: April 2022

Abstract
The use of grass cultivation in the restoration of degraded ecosystems is widespread, in order to reveal the effect of different grass cultivation patterns on the community structure of soil mites in the integrated management area of rocky desertification. In April and July 2021, a total of 2782 soil mites belonging to 3 orders, 42 families, and 73 genera were captured from three typical grass cultivation, Lolium perenne, Dactylis glomerata and Trifolium repens, and the traditional Zea mays as a control sample, in the integrated management area of potential-light rocky desertification in the karst plateau mountains of Salaxi, Guizhou Province. The soil mite community structure was analyzed using number of taxa (genera), number of individuals, diversity index, community similarity index, MI index of predatory mites, and MGP analysis of oribatid mite ecological taxa. The results showed that: (1) The summer has a more prosperous composition and diversity of soil mites across habitats, while the dominant genera of soil mites show a differential distribution across habitats; the number of soil mite genera, individuals and individual densities was significantly higher in the three grass cultivation habitats than the Zea mays habitat, and surface aggregation of soil mites is more pronounced. (2) There were differences in soil mite community structure among the three grass cultivation patterns, with a regularity of Lolium perenne > Dactylis glomerata > Trifolium repens in the composition of soil mites genera and the number of individuals, and the proportion of shared genera was not high. (3) The diversity of soil mites varied according to the environment and season, with the highest diversity of soil mites in Lolium perenne habitats; both the community similarity analysis and the CCA analysis showed that Lolium perenne and Dactylis glomerata habitats had the highest similarity of soil mite communities (4) Predatory mites were dominated by r-selective ecotypes, and oribatida were dominated by O and P type ecotypes under the three habitat patterns. (5) Soil nutrient conditions were more favorable in Trifolium repens habitats, while soil water content was higher in Dactylis glomerata environment, and correlation analysis indicated that TK was a key environmental factor influencing soil mite community composition and diversity. Based on the above results, it is further elaborated that the artificial grass restoration model not only improves the nutrient supply of soil N, P, and K but also significantly increases the composition and diversity of soil mite species, which is beneficial to the restoration of soil mite communities and is very helpful in terms of achieving self-sustainability and restoration of soil functions in rocky desertification areas.
Recent progress in the use of thermogelling polymers for treatment of ophthalmic conditions
Authors: Omar Jasmin , Dreiss Cécile A , Loh Xian Jun 
Published: April 2022

Abstract
Ocular diseases have serious implications on patients’ lives, with the majority causing blindness if left untreated. In 2020 it was estimated that 43 million people were blind worldwide which is expected to increase to 61 million by 2050. Due to the eye’s complex structure and defence mechanisms, there has been an ongoing challenge to deliver drugs which can penetrate the eyes’ barrier and reside at the site of action. Recent advances focus on the use of hydrogels, in particular temperature-responsive hydrogels, ‘thermogels’, to improve the properties of current therapies. Formulating a hydrogel-based system has shown to increase the bioavailability and biodegradability, provide a sustained release profile, enhance the drug permeation and residence time, as well as reduce the frequency of applications. This article provides a review of progress made over the past 5 years (2017–2021) using ‘thermogels’ for the treatment of some common or life-threatening ophthalmic conditions.