bluuebunny/crossref_metadata_2025 huggingface dataset:
Ferroelectricity and pseudo-coherent growth in HfO2/SrHfO3 nanolaminates
Authors: Yamada Hiroyuki , Toyosaki Yoshikiyo , Sawa Akihito
Published: March 2023

Ferroelectricity in thin films of HfO2 has been the subject of extensive studies in materials science as well as device applications. The emergence of ferroelectricity is attributable to the orthorhombic phase (Pca21) of HfO2, stabilized in the films by metal-element doping, strains from substrates and electrode films, and oxygen deficiency. Recently, ferroelectricity has been reported in nanolaminates of HfO2 with other oxides such as ZrO2 and Al2O3, implying that nanolaminates are another effective way to bring about ferroelectricity in HfO2. However, the mechanism of orthorhombic phase stabilization in nanolaminates is not fully understood. In this study, we demonstrated that ferroelectricity emerges in nanolaminates consisting of undoped HfO2 and perovskite SrHfO3 deposited on Sn-doped In2O3 bottom electrodes, when the thickness of HfO2 layers was ≥6 nm. For nanolaminates in which the thickness of the HfO2 layers was ≤5 nm, ferroelectricity was remarkably suppressed due to Sr-incorporation into the HfO2 layers at the interface. In those nanolaminates, the crystal orientations of HfO2 grains were well aligned throughout the HfO2 layers, indicating that the HfO2 layers grew in a pseudo-coherent manner. This study aids to understand the stabilization of the ferroelectric orthorhombic phase in nanolaminates in terms of their structural properties.
Information geometry and Bose–Einstein condensation
Authors: Pessoa Pedro
Published: March 2023

It is a long held conjecture in the connection between information geometry (IG) and thermodynamics that the curvature endowed by IG diverges at phase transitions. Recent work on the IG of Bose–Einstein (BE) gases challenged this conjecture by saying that in the limit of fugacity approaching unit—where BE condensation is expected—the curvature does not diverge; rather, it converges to zero. However, as the discontinuous behavior that identifies condensation is only observed at the thermodynamic limit, a study of the IG curvature at a finite number of particles, N, is in order from which the thermodynamic behavior can be observed by taking the thermodynamic limit (N→∞) posteriorly. This article presents such a study. We find that for a trapped gas, as N increases, the values of curvature decrease proportionally to a power of N, while the temperature at which the maximum value of curvature occurs approaches the usually defined critical temperature. This means that, in the thermodynamic limit, the curvature has a limited value where a phase transition is observed, contradicting the forementioned conjecture.
Bayesian modeling of scattered light in the LIGO interferometers
Authors: Udall R. P. , Davis D.
Published: March 2023

Excess noise from scattered light poses a persistent challenge in the analysis of data from gravitational wave detectors such as Laser Interferometer Gravitational-wave Observatory. We integrate a physically motivated model for the behavior of these “glitches” into a standard Bayesian analysis pipeline used in gravitational wave science. This allows for the inference of the free parameters in this model, and subtraction of these models to produce glitch-free versions of the data. We show that this inference is an effective discriminator of the presence of the features of these glitches, even when those features may not be discernible in standard visualizations of the data.
Percolation critical exponents in cluster kinetics of pulse-coupled oscillators
Authors: Gwon Gangyong , Cho Young Sul
Published: March 2023

Transient dynamics leading to the synchrony of a type of pulse-coupled oscillators, so-called scrambler oscillators, has previously been studied as an aggregation process of synchronous clusters, and a rate equation for the cluster size distribution has been proposed. However, the evolution of the cluster size distribution for general cluster sizes has not been fully understood yet. In this paper, we study the evolution of the cluster size distribution from the perspective of a percolation model by regarding the number of aggregations as the number of attached bonds. Specifically, we derive the scaling form of the cluster size distribution with specific values of the critical exponents using the property that the characteristic cluster size diverges as the percolation threshold is approached from below. Through simulation, it is confirmed that the scaling form well explains the evolution of the cluster size distribution. Based on the distribution behavior, we find that a giant cluster of all oscillators is formed discontinuously at the threshold and also that further aggregation does not occur like in a one-dimensional bond percolation model. Finally, we discuss the origin of the discontinuous formation of the giant cluster from the perspective of global suppression in explosive percolation models. For this, we approximate the aggregation process as a cluster–cluster aggregation with a given collision kernel. We believe that the theoretical approach presented in this paper can be used to understand the transient dynamics of a broad range of synchronizations.
N-polar GaN/AlGaN/AlN high electron mobility transistors on single-crystal bulk AlN substrates
Authors: Kim Eungkyun , Zhang Zexuan , Encomendero Jimy , Singhal Jashan , Nomoto Kazuki , Hickman Austin , Wang Cheng , Fay Patrick , Toita Masato , Jena Debdeep , Xing Huili Grace
Published: March 2023

Recent observation of high density polarization-induced two-dimensional electron gases in ultra-thin N-polar GaN layers grown on single-crystal AlN has enabled the development of N-polar high electron mobility transistors (HEMTs) on AlN. Such devices will take advantage of thermal and power handling capabilities of AlN, while simultaneously benefitting from the merits of N-polar structures, such as a strong back barrier. We report the experimental demonstration of N-polar GaN/AlGaN/AlN HEMTs on single-crystal AlN substrates, showing an on-current of 2.6 A/mm with a peak transconductance of 0.31 S/mm. Small-signal RF measurements revealed speeds exceeding ft/fmax = 68/100 GHz. These results pave the way for developing RF electronics with excellent thermal management based on N-polar single-crystal AlN.
Antiferroelectric orthorhombic P-to-R phase transition induced exotic electrocaloric effect in NaNbO3-based lead-free ceramics
Authors: Li Feng , Liu Wei , Ma Jianxing , Long Mingsheng , Lou Xiaojie , Li Kai , Wang Chunchang , Shan Lei
Published: March 2023

Phase transition is expected in designing high-performance electrocaloric effect (ECE). However, hidden antiferroelectricity in NaNbO3-based ceramics complicates ECE evolution as compared to conventional ferroic materials. Therefore, a NaNbO3−xBi0.5Li0.5TiO3 (x = 0.08, 0.10, and 0.12) system is introduced to explore ECE performance in P (Pbma), Q (P21ma), and R (Pnma) phases since a Bi0.5Li0.5TiO3 dopant plays a Janus role in stabilizing ferroelectric Q (x = 0.08 and 0.10) and inducing the antiferroelectric (AFE) relaxor R phase (x = 0.12). Rietveld refinement reveals a phase structure change from the P/Q to R state. Bi0.5Li0.5TiO3 addition makes a downshift of P-to-R transition temperature accompanied by an increase in relaxation property, as certified by dielectric analysis/piezoelectric force images, in situ XRD/Raman spectra, and ferroelectric tests. Additionally, a square P–E loop evolves into less-sharp and finally changes into a slant one with increasing Bi0.5Li0.5TiO3 content. ECE is directly measured, and its peak value increases from 0.15 K for x = 0.08 and 0.21 K for x = 0.10 and finally to 0.11 K for x = 0.12 composition. Interestingly, dual ECE peaks appear in x = 0.10, and it is probably contributed by R relaxor polar nanodomains. This work not only clarifies actual ECE behavior in AFE orthorhombic (P/R) NaNbO3-based ceramics but also fulfills understandings of AFE P-to-R transitions in modulating ECE.
On the generalized Snell's law for the design of elastic metasurfaces
Authors: Li Chun Min , Zhang Shengyuan , Chen Haibo , Ye Wenjing
Published: March 2023

As the most popular mechanism, the generalized Snell's law has been applied extensively to design metasurfaces for wave manipulation. By modulating phase profile using metasurfaces, various novel wave transformations have been demonstrated. However, it has been found that the performance of these metasurfaces cannot be fully determined by the generalized Snell's law and in some cases, the wave fields appear to be contradictory to what predicted by the generalized Snell's law. In this work, a systematic numerical study is conducted to investigate the generalized Snell's law for elastic waves. The inherent assumptions of the generalized Snell's law are examined first followed by the study of the effects of various implementation issues on the performance of the metasurfaces. In particular, the fundamental mechanism for producing wave components that do not obey the generalized Snell's lay is identified and theoretically justified. Design guidelines for metasurfaces for improved performance are provided.
Heat and mass transport from neutrally suspended oblate spheroid in simple shear flow
Authors: Wang Yanxing , Wan Hui , Gonzalez Pizarro Ruben , Lim Seokbin , Shu Fangjun
Published: March 2023

Through high-fidelity numerical simulation based on the lattice Boltzmann method, we have conducted an in-depth study on the heat and mass transport from an oblate spheroid neutrally suspended in a simple shear flow. In the simulation, the temperature and mass concentration are modeled as a passive scalar released at the surface of the spheroid. The fluid dynamics induced by the interaction between the carrier fluid and the suspended spheroid, as well as the resultant scalar transport process, have been extensively investigated. A coupled transport mechanism comprising several components of the flow around the oblate spheroid has been identified. The effects of the Reynolds number and the aspect ratio of the spheroid on the flow characteristics and scalar transport rate are examined. The variation of the nondimensional scalar transport rate suggests that the effect of spheroid shape on scalar transfer rate can be decoupled from the effects of Peclet and Reynolds numbers, which facilitates the development of a correlation of scalar transfer rate for oblate spheroids based on the well-developed correlations for a sphere.
Low electron density channel revealed in the plasma layer of hypersonic vehicle under a novel magnetic control
Authors: Zheng Xiaojing , Chen Siyao , Jin Ke
Published: March 2023

The “communication blackout” occurs during the reentry of hypersonic vehicles, that is, the electromagnetic wave cannot pass through the plasma sheath due to high electron density formed around the vehicle, which has drawn much attention but has not yet been solved. In this paper, a novel magnetic control approach is proposed, in which a periodic magnetic field is applied near the head of the aircraft. Based on the magnetohydrodynamic simulation, a low electron density channel across the plasma sheath of vehicle under the magnetic control is revealed for the first time, which probably make Ka-band electromagnetic wave pass through. We also find that the reason for the low electron density channel is the variation of the vortex structure in the plasma flow near the wall, by the electromagnetic force exerted on the flow. Furthermore, the optimal magnetic field frequency for generating the low electron density channel is obtained. These findings will be of significant benefit to the solutions for the communication blackout problems.
Restoring Australia’s long-term innovation requires investment in basic research
Authors: Harrison Rosemary S. , Barnard Ross T. , Pregelj Lisette
Published: March 2023

It is well established that basic research underpins long-term innovation outputs such as transformative drugs and medical devices. However, Australia may be hobbling its long-term innovation capabilities by decreasing investment in basic research. Although there has been recent growth in our local venture capital and biopharmaceutical business sectors (that typically fund applied research and experimental development), both are comparatively undersized. Initiatives are needed to ensure long-term commitment to basic research at globally competitive levels and to ensure that long-term innovation capabilities are supported.
Macaques recognize features in synthetic images derived from ventral stream neurons
Authors: Mueller Katherine N. , Carter Mary C. , Kansupada Jeevun A. , Ponce Carlos R.
Published: March 2023

Primates can recognize features in virtually all types of images, an ability that still requires a comprehensive computational explanation. One hypothesis is that visual cortex neurons learn patterns from scenes, objects, and textures, and use these patterns to interpolate incoming visual information. We have used machine learning algorithms to instantiate visual patterns stored by neurons—we call these highly activating images prototypes. Prototypes from inferotemporal (IT) neurons often resemble parts of real-world objects, such as monkey faces and body parts, a similarity established via pretrained neural networks [C. R. Ponce
et al
., 
Cell
177
, 999–1009.e10 (2019)] and naïve human participants [A. Bardon, W. Xiao, C. R. Ponce, M. S. Livingstone, G. Kreiman,
Proc. Natl. Acad. Sci. U.S.A.
119
, e2118705119 (2022)]. However, it is not known whether monkeys themselves perceive similarities between neuronal prototypes and real-world objects. Here, we investigated whether monkeys reported similarities between prototypes and real-world objects using a two-alternative forced choice task. We trained the animals to saccade to synthetic images of monkeys, and subsequently tested how they classified prototypes synthesized from IT and primary visual cortex (V1). We found monkeys classified IT prototypes as conspecifics more often than they did random generator images and V1 prototypes, and their choices were partially predicted by convolutional neural networks. Further, we confirmed that monkeys could abstract general shape information from images of real-world objects. Finally, we verified these results with human participants. Our results provide further evidence that prototypes from cortical neurons represent interpretable abstractions from the visual world.
Research on Navigation Motion Control Method of Intelligent Delivery Robot for Substation Maintenance
Authors: Yu Yan , Wen Kang , Yi Xiao , Chuang Gong , Wei Jiang
Published: March 2023

The intelligent delivery robot for substation maintenance is a kind of intelligent equipment for substation maintenance of power system, which can assist or even replace the artificial equipment to carry equipment in the substation. It has important theoretical significance and practical application value for the automation of intelligent operation and maintenance management of substation. Substation maintenance the autonomous navigation of the robot motion control is the key to promote its practical application, based on this, this paper proposes a substation maintenance intelligent vehicle robot navigation motion control method, the ground mobile robot motion control model was established, and decomposition to the movement of robot in space, deduced the robot along the X, Y, Z direction of movement error expressions, based on this, the motion of the robot controller is designed and selected the suitable Lyapunov function proved that the stability of the robot system motion, finally, the robot system integration design, substation inspection robot physical prototype system is developed and in substations is verified by field movement navigation motion control method is feasible and effective.
A CVT Parameter Identification Method Based on Improved Grey Wolf Optimizer
Authors: Yu Yuchen , Chen Xuxuan , Tang Hao , Lei Yuanyuan
Published: March 2023

Aiming at the problem that harmonic simulation model parameters of capacitive voltage transformer (CVT) are difficult to determine, an identification method of equivalent circuit parameters of CVT is proposed. By studying the frequency response, a nonlinear equation about the equivalent circuit parameters of CVT is established. By analyzing the characteristics of the equation and combining with the actual use, an improved grey wolf optimizer is applied to achieve the accurate identification of the key parameters of CVT. On the basis of grey wolf optimizer, the algorithm introduced a good point set and comprehensive dimension learning strategy to prevent the algorithm from falling into local optimum, and modified the convergence factor according to the actual needs to improve the convergence accuracy. Finally, three numerical examples are simulated by MATLAB/Simulink software, which proves the feasibility and superiority of the proposed method in CVT application.
Fiber Optic MEMS Ultrasonic Sensor and its Application in Partial Discharge Detection
Authors: Liu Kang , Shi Ji , Xie Lang , Zhou Qian , Zhang Juanjuan , Liu Yurui
Published: March 2023

In this paper, an optical fiber based ultrasonic sensor was designed and applied to the detection and position of partial discharge (PD). The Fabry-Perot interferometer with a micro-electromechanical system (MEMS) diaphragm has been proven to have high sensitivity, with broadband acoustic frequency response up to 500 kHz and wide directivity. In the PD detection experiment, the minimum detectable pressure (MDP) of the fiber optical MEMS sensor is achieving 0.455μPaHz
-1/2. In addition, four ultrasonic sensors are arranged around the ultrasonic source to conduct localization experiments. The results show that the system has excellent localization performance in x, y and z directions. The favourable acoustic performance of the MEMS sensor provides a high-sensitivity and high signal-to-noise ratio (SNR) detection method for PD detection.
Parameter Design of Software Phase-Locked Loop Based on Z-domain
Authors: Lv Fei , Zhang Songtao , Ji Zhe
Published: March 2023

Exact phase information is essential for the smooth operation of most modern power conversion devices. Software phase locked loop (SPLL) has favorable condition for free design and high adaptability to gain phase and frequency information of power voltage quickly and accurately. In this thesis, we analyze SPLL principle, obtain the z-domain SPLL linearization model, then analyze the stability and error of the SPLL linearized model, and design parameters o the SPLL controller under the z-domain, and finally, simulate and verify for two power voltage phase jump cases. The simulation results show the correctness of the design method.
Multi-mode Control Method Developed for Aircraft System Management
Authors: Zhang Ying , Peng Di , Wang Shihui , Tao Yizhu , Hu Yufei
Published: March 2023

This paper studies the analysis of aircraft system which has the development for multi-mode architecture, as well as the application of multi-mode control, multi-mode monitoring and multi-mode fast parallel management. Through the research and analysis of multi-mode architecture, multi-mode control algorithm, multi-mode health monitoring algorithm and multi-mode rapid parallel test. GigaDevice’s MCU (GD32F450) is used using an MCU, and the FPGA is two Chip Anlu’s AL3A10BGA256, FLASH uses GigaDevice’s GD25Q64CSIG to simulate the aircraft development system. The effectiveness of a multi-mode control management method developed for aircraft was developed. This method changes the single-mode management and disposal scheme of traditional aircraft, and adopts the mode control management of real-time detection. It effectively saves system resource consumption and expenditure in aircraft development.
Numerical Investigation of Piezoelectric Vibration Energy Harvesting with L-shaped Beam
Authors: Lin Gang , Xie Yinghe , Zhong Qihao , Zeng Wei , Chen Zhenliang , Zhang Xi
Published: March 2023

Energy harvesting efficiency is a crucial problem in practical engineering applications of piezoelectric vibration energy harvester. L-shaped piezoelectric vibration energy harvester has the potential of broadband and high energy harvesting efficiency. Different vibration energy harvesting structures are numerically investigated here to compare their energy harvesting efficiencies, including traditional cantilever beam structure and L-shaped structures. Verification and validation of the numerical simulation approach adopted here are conducted firstly, through comparing the numerical results with the theoretical and experimental results respectively. Modal analysis and harmonic response analysis are conducted consequently to obtain the natural frequencies and voltage outputs of different harvesters. Numerical results show that, L-shaped harvester is a potential broadband energy harvesting structure with higher energy harvesting efficiency compared with traditional cantilever harvester.
Research on Grid-connected Performance of Solar-thermal-storage Coupled System Including Thermal, PV and Flywheel
Authors: Li Xutao , Yu Dahai , Li Yan , Bai Shibin , Ren Yong , Nian Ming
Published: March 2023

With the rapid development of renewable energy, the demand for frequency regulation and peak shaving of coal-fired power plants is increasing. As the utilization hours of coal-fired power plants are gradually reduced, the economy of coal-fired power plants is gradually reduced. In order to improve the economic benefits of thermal power plants, thermal power plants are changing from the income model dominated by power generation to the income model of “cogeneration of power generation and auxiliary power service”. Among them, the energy storage system of Lingwu power plant of Ningxia electric power company of Guoneng group belongs to the first large-scale thermal power plant large-capacity solar thermal energy storage (flywheel) project at home and abroad. While ensuring the functions of conventional power supply, heating and cogeneration, the system can also provide auxiliary power services, support the safe and stable operation of a large power grid, and improve the flexibility and economic benefits of traditional thermal power plants. With the application of new technologies in coal-fired power plants, improving the economy of coal-fired generating units and power auxiliary services will be the main direction of power generation groups. At the same time, it also puts forward new requirements for power grid operation.
Research on Tool Carts Based on Modular Drilling Rig Assembly
Authors: Wang Xinkuan , Liu Ruijun , Liu Quan , Zhang Yiqing , Gao Yiran
Published: March 2023

Drilling rigs play an important role in the foundation construction of UHV engineering, with the rapid development of power construction, the demand for drilling rigs by related construction units is also increasing, especially drilling rigs adapted to mountain environments, and the development of related construction tools has huge market prospects. In view of the problem of UHV engineering mountain construction machine entry, the traditional integral drilling rig has been transformed into a modular drilling rig, and the modular construction equipment is transported to the construction site through the cableway, and then the module is assembled. To this end, this paper carries out the research of tool carts to assist modular equipment assembly and auxiliary construction, introduces the design requirements and overall design scheme of tool carts, and studies the walking chassis, frame module, power module, boom module, mechanical gripper module, etc. The research results of this paper can change the existing construction situation, shorten the assembly time of construction equipment, and promote the development of modular construction equipment.
Analysis on the Evolution and Seasonal Variation of the Ulleung Warm Eddy
Authors: Kong Chuiri
Published: March 2023

The Ulleung Warm Eddy (UWE) is a semi-permanent eddy, which has a very important impact on material transport in the Japan Sea, so we use aviso(Archiving, Validation and Interpretation of Satellite Oceanographic data) data and ARM3D data to analyze the seasonal variation of UWE that appeared in a total of 28 years from 1993 to 2020. We also analyze the evolution of the UWE that appears in 2019, and found that the eddies merging (splitting) can cause sudden increases (drops) in the nature of UWE. Seasonally, UWE’s area and eddy amplitude are strong in winter and spring, and weak in summer and autumn. The Tsushima Current (TC) has an important influence on UWE. The stronger (weaker) flow of TC, the weaker (stronger) the area and eddy amplitude of UWE.
Calculation method based on a BGO+SiPM detector for ^13N gas coincidence detection efficiency
Authors: Chen X. , Hu C.Y. , Qu G.P. , Zheng B. , Zhang H.J.
Published: March 2023

To reduce the lower detection limit of 13N gas, we
design a γ-γ coincidence measuring instrument
including two detectors, a sampling vessel, and a summation and
coincidence circuit in this work. The detector uses a
13 cm × 5 cm oversized Bi4Ge3O12 
(BGO) scintillator and 172 silicon photomultiplier (SiPM) tubes,
which greatly reduce the instrument size while improving the
coincidence detection efficiency. The 13N gas coincidence
detection efficiency is improved by installing a multilayer metal
absorber plate inside the cylindrical sampling vessel. Due to the
short half-life of 13N gas, it cannot be stored for a long
time; additionally, it is difficult to obtain. It is not possible to
directly scale the coincidence detection efficiency of this
instrument using a 13N gas source with known activity in
engineering projects. Based on the spatial distribution of the
relative efficiency of the sampling vessel and the absolute
efficiency of the reference point, we use a combination of 22Na
solid point source experiments and Monte Carlo simulations to
calculate the coincidence detection efficiency of this instrument
for 13N gas in this work; the coincidence detection efficiency
is approximately 4%, which meets the engineering design
requirements.
Interstitial fluid flow contributes to prostate cancer invasion and migration to bone; study conducted using a novel horizontal flow bioreactor
Authors: Jasuja Haneesh , Jaswandkar Sharad V , Katti Dinesh R , Katti Kalpana S
Published: March 2023

Prostate cancer bone metastasis is the leading cause of cancer-related mortality in men in the United States, causing severe damage to skeletal tissue. The treatment of advanced-stage prostate cancer is always challenging due to limited drug treatment options, resulting in low survival rates. There is a scarcity of knowledge regarding the mechanisms associated with the effects of biomechanical cues by the interstitial fluid flow on prostate cancer cell growth and migration. We have designed a novel bioreactor system to demonstrate the impact of interstitial fluid flow on the migration of prostate cancer cells to the bone during extravasation. First, we demonstrated that a high flow rate induces apoptosis in PC3 cells via TGF-β1 mediated signaling; thus, physiological flow rate conditions are optimum for cell growth. Next, to understand the role of interstitial fluid flow in prostate cancer migration, we evaluated the migration rate of cells under static and dynamic conditions in the presence or absence of bone. We report that CXCR4 levels were not significantly changed under static and dynamic conditions, indicating that CXCR4 activation in PC3 cells is not influenced by flow conditions but by the bone, where CXCR4 levels were upregulated. The bone-upregulated CXCR4 levels led to increased MMP-9 levels resulting in a high migration rate in the presence of bone. In addition, upregulated levels of α
v
β
3 integrins under fluid flow conditions contributed to an overall increase in the migration rate of PC3 cells. Overall, this study demonstrates the potential role of interstitial fluid flow in prostate cancer invasion. Understanding the critical role of interstitial fluid flow in promoting prostate cancer cell progression will enhance current therapies for advanced-stage prostate cancer and provide improved treatment options for patients.
Evaluating polythiophenes as temperature sensing materials using combinatorial inkjet printing
Authors: Roy Anindya Lal , Beaumont Catherine , Leclerc Mario , Walus Konrad
Published: March 2023

Polythiophenes comprise a class of emerging materials with potential applications in the field of temperature sensing. In this article, we validate and apply an integrated blending and printing methodology to combinatorially study libraries of pristine and compositionally graded blends of polythiophenes PEDOT:PSS and P(S-EDOT) (a PEDOT-like self-doped conjugated polymer) to understand their intrinsic electrical conductivity behaviour and along with its temperature dependence on blend composition and ambient temperature. Hypothesis testing is conducted to identify optima in electrical conductivity from combinations of input material proportions intended to meet multiple requirements otherwise difficult to achieve in any single-component solution-processable material. We chose PEDOT:PSS as a commercial developed intrinsically conductive polythiophene and with it, compared a novel self-doped polythiophene P(S-EDOT) as its potential replacement or complement as a sensor material. The electrical and morphological characteristics for both polymers and their blends were investigated for use as different components of temperature sensing applications. Different error sources within the process flow were considered for statistically significant conclusions regarding the utility of different compositions for different aspects of temperature sensing.
A perspective on the neuromorphic control of legged locomotion in past, present, and future insect-like robots
Authors: Szczecinski Nicholas S , Goldsmith C A , Nourse William R P , Quinn Roger D
Published: March 2023

This article is a historical perspective on how the study of the neuromechanics of insects and other arthropods has inspired the construction, and especially the control, of hexapod robots. Many hexapod robots’ control systems share common features, including: 1. Direction of motor output of each joint (i.e. to flex or extend) in the leg is gated by an oscillatory or bistable gating mechanism; 2. The relative phasing between each joint is influenced by proprioceptive feedback from the periphery (e.g. joint angles, leg load) or central connections between joint controllers; and 3. Behavior can be directed (e.g. transition from walking along a straight path to walking along a curve) via low-dimensional, broadly-acting descending inputs to the network. These distributed control schemes are inspired by, and in some robots, closely mimic the organization of the nervous systems of insects, the natural hexapods, as well as crustaceans. Nearly a century of research has revealed organizational principles such as central pattern generators, the role of proprioceptive feedback in control, and command neurons. These concepts have inspired the control systems of hexapod robots in the past, in which these structures were applied to robot controllers with neuromorphic (i.e. distributed) organization, but not neuromorphic computational units (i.e. neurons) or computational hardware (i.e. hardware-accelerated neurons). Presently, several hexapod robots are controlled with neuromorphic computational units with or without neuromorphic organization, almost always without neuromorphic hardware. In the near future, we expect to see hexapod robots whose controllers include neuromorphic organization, computational units, and hardware. Such robots may exhibit the full mobility of their insect counterparts thanks to a ‘biology-first’ approach to controller design. This perspective article is not a comprehensive review of the neuroscientific literature but is meant to give those with engineering backgrounds a gentle introduction into the neuroscientific principles that underlie models and inspire neuromorphic robot controllers. A historical summary of hexapod robots whose control systems and behaviors use neuromorphic elements is provided. Robots whose controllers closely model animals and may be used to generate concrete hypotheses for future animal experiments are of particular interest to the authors. The authors hope that by highlighting the decades of experimental research that has led to today’s accepted organization principles of arthropod nervous systems, engineers may better understand these systems and more fully apply biological details in their robots. To assist the interested reader, deeper reviews of particular topics from biology are suggested throughout.
Artificial visual neuron based on threshold switching memristors
Authors: Wen Juan , Zhu Zhen-Ye , Guo Xin
Published: March 2023

The human visual system encodes optical information perceived by photoreceptors in the retina into neural spikes and then processes them by the visual cortex, with high efficiency and low energy consumption. Inspired by this information processing mode, an universal artificial neuron constructed with a resistor (Rs) and a threshold switching memristor can realize rate coding by modulating pulse parameters and the resistance ofRs. Owing to the absence of an external parallel capacitor, the artificial neuron has minimized chip area. In addition, an artificial visual neuron is proposed by replacingRsin the artificial neuron with a photo-resistor. The oscillation frequency of the artificial visual neuron depends on the distance between the photo-resistor and light, which is fundamental to acquiring depth perception for precise recognition and learning. A visual perception system with the artificial visual neuron can accurately and conceptually emulate the self-regulation process of the speed control system in a driverless automobile. Therefore, the artificial visual neuron can process efficiently sensory data, reduce or eliminate data transfer and conversion at sensor/processor interfaces, and expand its application in the field of artificial intelligence.
FAMetA: a mass isotopologue-based tool for the comprehensive analysis of fatty acid metabolism
Authors: Alcoriza-Balaguer María I , García-Cañaveras Juan C , Benet Marta , Juan-Vidal Oscar , Lahoz Agustín
Published: March 2023

The use of stable isotope tracers and mass spectrometry (MS) is the gold standard method for the analysis of fatty acid (FA) metabolism. Yet, current state-of-the-art tools provide limited and difficult-to-interpret information about FA biosynthetic routes. Here we present FAMetA, an R package and a web-based application (www.fameta.es) that uses 13C mass isotopologue profiles to estimate FA import, de novo lipogenesis, elongation and desaturation in a user-friendly platform. The FAMetA workflow covers the required functionalities needed for MS data analyses. To illustrate its utility, different in vitro and in vivo experimental settings are used in which FA metabolism is modified. Thanks to the comprehensive characterization of FA biosynthesis and the easy-to-interpret graphical representations compared to previous tools, FAMetA discloses unnoticed insights into how cells reprogram their FA metabolism and, when combined with FASN, SCD1 and FADS2 inhibitors, it enables the identification of new FAs by the metabolic reconstruction of their synthesis route.
STEEL enables high-resolution delineation of spatiotemporal transcriptomic data
Authors: Chen Yamao , Zhou Shengyu , Li Ming , Zhao Fangqing , Qi Ji
Published: March 2023

Advances in spatial transcriptomics enlarge the use of single cell technologies to unveil the expression landscape of the tissues with valuable spatial context. Here, we propose an unsupervised and manifold learning-based algorithm, Spatial Transcriptome based cEll typE cLustering (STEEL), which identifies domains from spatial transcriptome by clustering beads exhibiting both highly similar gene expression profiles and close spatial distance in the manner of graphs. Comprehensive evaluation of STEEL on spatial transcriptomic datasets from 10X Visium platform demonstrates that it not only achieves a high resolution to characterize fine structures of mouse brain but also enables the integration of multiple tissue slides individually analyzed into a larger one. STEEL outperforms previous methods to effectively distinguish different cell types/domains of various tissues on Slide-seq datasets, featuring in higher bead density but lower transcript detection efficiency. Application of STEEL on spatial transcriptomes of early-stage mouse embryos (E9.5–E12.5) successfully delineates a progressive development landscape of tissues from ectoderm, mesoderm and endoderm layers, and further profiles dynamic changes on cell differentiation in heart and other organs. With the advancement of spatial transcriptome technologies, our method will have great applicability on domain identification and gene expression atlas reconstruction.
RSCanner: rapid assessment and visualization of RNA structure content
Authors: Mahadeshwar Gandhar , Tavares Rafael de Cesaris Araujo , Wan Han , Perry Zion R , Pyle Anna Marie
Published: March 2023

Motivation

The increasing availability of RNA structural information that spans many kilobases of transcript sequence imposes a need for tools that can rapidly screen, identify, and prioritize structural modules of interest.

Results

We describe RNA Structural Content Scanner (RSCanner), an automated tool that scans RNA transcripts for regions that contain high levels of secondary structure and then classifies each region for its relative propensity to adopt stable or dynamic structures. RSCanner then generates an intuitive heatmap enabling users to rapidly pinpoint regions likely to contain a high or low density of discrete RNA structures, thereby informing downstream functional or structural investigation.

Availability and implementation

RSCanner is freely available as both R script and R Markdown files, along with full documentation and test data (https://github.com/pylelab/RSCanner).
Structural Elucidation of Novel Degradation Impurity and Development, Validation of a Single HPLC Method for all Putative Impurities of Clobetasol Propionate in a Foam Drug Product
Authors: Ketha Naga Venkata Durga Prasad , Kolli Deepti , Subbappa Praveen Kumar
Published: March 2023

Clobetasol Propionate is a highly strong corticosteroid that is used in a variety of topical medication formulations, including foam, ointment, lotion, spray and shampoo; with a dosage strength of 0.05% (w/w). The goal of this research was to identify and characterize a substantial unknown impurity (UK) detected during the stability testing of a Clobetasol Propionate foam pharmaceutical product in accelerated conditions (40°C and 75% relative humidity). Developing a single, robust and accurate HPLC method that is LC–MS compatible for quantifying all 14 potential Clobetasol Propionate impurities in therapeutic drugs is another goal. Preparative column chromatography was used to separate the impurity, and spectroscopic techniques like IR, NMR and MS were used to characterize its structure. The structure of isolated UK was effectively characterized and defined using spectroscopic data evaluation. The chromatographic method has also been validated according to the International Conference on Hominization's Q (2) quality guidelines. The isolated and characterized impurity had the same equivalence as the impurity found during stability testing. Precision, accuracy, linearity, robustness and ruggedness are all met in the method validation data.
Deprivation and chronic kidney disease—a review of the evidence
Authors: Grant Christopher H , Salim Ehsan , Lees Jennifer S , Stevens Kate I
Published: March 2023

The relationship between socioeconomic deprivation and health is inequitable. Chronic kidney disease (CKD) is an archetypal disease of inequality, being more common amongst those living in deprivation. The prevalence of CKD is rising driven by an increase in lifestyle-related conditions. This narrative review describes deprivation and its association with adverse outcomes in adults with non-dialysis-dependent CKD including disease progression, end-stage kidney disease, cardiovascular disease and all-cause mortality. We explore the social determinants of health and individual lifestyle factors to address whether patients with CKD who are socioeconomically deprived have poorer outcomes than those of higher socioeconomic status. We describe whether observed differences in outcomes are associated with income, employment, educational attainment, health literacy, access to healthcare, housing, air pollution, cigarette smoking, alcohol use or aerobic exercise. The impact of socioeconomic deprivation in adults with non-dialysis-dependent CKD is complex, multi-faceted and frequently under-explored within the literature. There is evidence that patients with CKD who are socioeconomically deprived have faster disease progression, higher risk of cardiovascular disease and premature mortality. This appears to be the result of both socioeconomic and individual lifestyle factors. However, there is a paucity of studies and methodological limitations. Extrapolation of findings to different societies and healthcare systems is challenging, however, the disproportionate effect of deprivation in patients with CKD necessitates a call to action. Further empirical study is warranted to establish the true cost of deprivation in CKD to patients and societies.
Revisiting the role of acute kidney injury in patients on immune checkpoint inhibitors: a good prognosis renal event with a significant impact on survival
Authors: García-Carro Clara , Jhaveri Kenar D , Sprangers Ben
Published: March 2023

In the last decade, immune checkpoint inhibitors (ICI) have become a cornerstone in the treatment of a wide range of malignancies. It is well established that ICI are associated with multiple immune-related adverse events, a spectrum of autoimmune toxicities, that can also affect the kidney. In this issue of Clinical Kidney Journal, Kanbay et al. report the first meta-analysis and systematic review evaluating the impact of ICI-related acute kidney injury (ICI-AKI) on long-term kidney and patient outcomes (including mortality). The authors report a high incidence of ICI-AKI (mostly mild AKI episodes) with high rates of recovery resulting in a good kidney outcomes. However, the occurrence of ICI-AKI has a significant impact on mortality in ICI-treated patients probably related to temporary or definitive cessation of ICI. Additional studies are needed to establish the safety of ICI re-challenging in patients with ICI-AKI, and to determine the optimal treatment strategy for them.
Plasma Glial Fibrillary Acidic Protein in the Alzheimer Disease Continuum: Relationship to Other Biomarkers, Differential Diagnosis, and Prediction of Clinical Progression
Authors: Shen Xue-Ning , Huang Shu-Yi , Cui Mei , Zhao Qian-Hua , Guo Yu , Huang Yu-Yuan , Zhang Wei , Ma Ya-Hui , Chen Shi-Dong , Zhang Ya-Ru , Chen Shu-Fen , Chen Ke-Liang , Cheng Wei , Zuo Chuan-Tao , Tan Lan , Ding Ding , Dong Qiang , Jeromin Andreas , Yen Tzu-Chen , Yu Jin-Tai
Published: March 2023

Background

Plasma glial fibrillary acidic protein (GFAP) has emerged as a promising biomarker in neurological disorders, but further evidence is required in relation to its usefulness for diagnosis and prediction of Alzheimer disease (AD).

Methods

Plasma GFAP was measured in participants with AD, non-AD neurodegenerative disorders, and controls. Its diagnostic and predictive value were analyzed alone or combined with other indicators.

Results

A total of 818 participants were recruited (210 followed). Plasma GFAP was significantly higher in AD than in non-AD dementia and non-demented individuals. It increased in a stepwise pattern from preclinical AD, through prodromal AD to AD dementia. It effectively distinguished AD from controls [area under the curve (AUC) > 0.97] and non-AD dementia (AUC > 0.80) and distinguished preclinical (AUC > 0.89) and prodromal AD (AUC > 0.85) from Aβ-normal controls. Adjusted or combined with other indicators, higher levels of plasma GFAP displayed predictive value for risk of AD progression (adjusted hazard radio= 4.49, 95%CI, 1.18–16.97, P = 0.027 based on the comparison of those above vs below average at baseline) and cognitive decline (standard-β=0.34, P = 0.002). Additionally, it strongly correlated with AD-related cerebrospinal fluid (CSF)/neuroimaging markers.

Conclusions

Plasma GFAP effectively distinguished AD dementia from multiple neurodegenerative diseases, gradually increased across the AD continuum, predicted the individual risk of AD progression, and strongly correlated with AD CSF/neuroimaging biomarkers. Plasma GFAP could serve as both a diagnostic and predictive biomarker for AD.
Universal School-Based Screenings for Depression and Suicide: Identifying Students at Risk of Suicide
Authors: Mirick Rebecca G , Berkowitz Larry , McCauley James , Bridger Joanna
Published: March 2023

Schools have an important role to play in adolescent suicide prevention. This article describes universal screenings for depression and suicidality as one component of the Signs of Suicide (SOS) program in middle and high schools following the suicide death of a student in the past few years. Of the students screened (N = 7,429), 11.0 percent of youth were identified as at risk by the screening tool; 17.3 percent received a same-day secondary screen with a mental health professional. (Students without an at-risk screen could request a meeting with a mental health professional, so more students received secondary screenings than screened at risk.) Characteristics associated with an at-risk screen on the screening tool were identified. Girls were twice as likely to be identified as at risk than boys, and students exposed to a suicide death in the past year were 1.3 times more likely to have an at-risk screen. There was no difference in at-risk screens for middle versus high school students, but middle schoolers were more likely to receive a secondary screening due to help seeking from school staff. The article concludes with a discussion of the implications for school administrators at middle and high schools, including recommendations to screen with both a screening tool and an option to speak to an adult, strategies for planning for secondary screenings, and advantages to universal screening following the suicide death of a student.