bluuebunny/crossref_metadata_2025 huggingface dataset:
Innate immune cell activation causes lung fibrosis in a humanized model of long COVID
Authors: Cui Lu , Fang Zhuoqing , De Souza Cristabelle Madona , Lerbs Tristan , Guan Yuan , Li Irene , Charu Vivek , Chen Shih-Yu , Weissman Irving , Wernig Gerlinde
Published: February 2023

COVID-19 remains a global pandemic of an unprecedented magnitude with millions of people now developing “COVID lung fibrosis.” Single-cell transcriptomics of lungs of patients with long COVID revealed a unique immune signature demonstrating the upregulation of key proinflammatory and innate immune effector genes CD47, IL-6, and JUN. We modeled the transition to lung fibrosis after COVID and profiled the immune response with single-cell mass cytometry in JUN mice. These studies revealed that COVID mediated chronic immune activation reminiscent to long COVID in humans. It was characterized by increased CD47, IL-6, and phospho-JUN (pJUN) expression which correlated with disease severity and pathogenic fibroblast populations. When we subsequently treated a humanized COVID lung fibrosis model by combined blockade of inflammation and fibrosis, we not only ameliorated fibrosis but also restored innate immune equilibrium indicating possible implications for clinical management of COVID lung fibrosis in patients.
Sea urchin mass mortalities 40 y apart further threaten Caribbean coral reefs
Authors: Levitan Don R. , Best Rachael M. , Edmunds Peter J.
Published: February 2023

In 1983 to 1984, a mass mortality event caused a Caribbean-wide, >95% population reduction of the echinoid grazer,
Diadema antillarum
. This led to blooms of algae contributing to the devastation of scleractinian coral populations. Since then,
D. antillarum
exhibited only limited and patchy population recovery in shallow water, and in 2022 was struck by a second mass mortality reported over many reef localities in the Caribbean. Half-a-century time-series analyses of populations of this sea urchin from St. John, US Virgin Islands, reveal that the 2022 event has reduced population densities by 98.00% compared to 2021, and by 99.96% compared to 1983. In 2021, coral cover throughout the Caribbean was approaching the lowest values recorded in modern times. However, prior to 2022, locations with small aggregations of
D. antillarum
produced grazing halos in which weedy corals were able to successfully recruit and become the dominant coral taxa. The 2022 mortality has eliminated these algal-free halos on St. John and perhaps many other regions, thereby increasing the risk that these reefs will further transition into coral-free communities.
Building a corpus of spoken Chinese interlanguage and some results of preliminary analyses
Authors: Du Hang
Published: February 2023

The corpus of spoken Chinese interlanguage in this study consists of over one million characters of transcribed student speech from data collected from nearly ten years of study abroad research. The main research method was a comparison with a similar corpus of spoken Chinese by native speakers. Preliminary analyses show that 11 of the top 20 most frequent words in both the learner corpus and native corpus are the same. Learners used some grammatical function words, such as把(bǎ),了(le),它(tā), and着(zhe) less than native speakers, while other ones, such as我(wǒ) and的(de), much more frequently. Possible explanations for these patterns, as well as pedagogical implications and directions for further research are discussed.
Precision Tests of the Nonlinear Mode Coupling of Anisotropic Flow via High-Energy Collisions of Isobars
Authors: Jia Jiangyong , Giacalone Giuliano , Zhang Chunjian
Published: February 2023

Valuable information on dynamics of expanding fluids can be inferred from the response of such systems to perturbations in their initial geometry. We apply this technique in high-energy 96Ru+96Ru and 96Zr+96Zr collisions to scrutinize the expansion dynamics of the quark-gluon plasma, where the initial geometry perturbations are sourced by the differences in deformations and radial profiles between 96Ru and 96Zr, and the collective response is captured by the change in anisotropic flow Vn
between the two collision systems. Using a transport model, we analyze how the nonlinear coupling between lower-order flow harmonics V
2 and V
3 to the higher-order flow harmonics V
4 and V
5, expected to scale as

V

4
NL

=

χ
4

V
2
2

and V
5NL = χ
5
V
2
V
3, gets modified as one moves from 96Ru+96Ru to 96Zr+96Zr systems. We find that these scaling relations are valid to high precision: variations of order 20% in V
4NL and V
5NL due to differences in quadrupole deformation, octupole deformation, and nuclear skin modify χ
4 and χ
5 by about 1–2%. Percent-level deviations are however larger than the expected experimental uncertainties and could be measured. Therefore, collisions of isobars with different nuclear structures are a unique tool to isolate subtle nonlinear effects in the expansion of the quark-gluon plasma that would be otherwise impossible to access in a single collision system.
Computationally driven design of low dielectric-loss epoxy resin for medium-frequency transformers
Authors: Wu Zhicheng , Fan Jiasheng , Zhao Yuxiao , Lin Binqi , Zhou Wenying , Zhang Qiaogen , Li Licheng
Published: February 2023

The design of low dielectric-loss epoxy resin (EP) systems plays an important role in the insulation optimization of medium-frequency transformers (MFTs). Due to the diversity of EP and curing agents, the traditional design method inspired by dielectric-loss measurements cannot complete low dielectric-loss EP systems design in plentiful candidate EP systems. In this study, molecular dynamics (MD) computation was introduced to drive the design of a low dielectric-loss EP system for MFTs. By analyzing the relationship between the dielectric loss and molecular motion of the EP systems, two MD results were selected as descriptors to indicate the dielectric loss of EP systems, including mean square displacement and α-transition temperature. Eventually, the low dielectric-loss EP system blending EP, methyl tetrahydrophthalic anhydride, and dodecenyl succinic anhydride was effectively designed according to the descriptors. The rationality of the computationally driven design was verified by broadband dielectric spectroscopy measurement and the finite element method. Compared with previous EP systems, MFT insulated with the designed EP system had not only a 40% lower dielectric loss (9.79 W) but a higher overload capacity. This study provides an effective method for the design of low dielectric-loss EP systems.
Surface temperature characterization of dielectric barrier discharge plasma actuator in quiescent air
Authors: Hatamoto Asami , Emori Kenta , Nishida Hiroyuki
Published: February 2023

Dielectric barrier discharge plasma actuators (DBDPAs) have been investigated for active flow control. The discharge induces ionic wind, which can be utilized for flow control; however, it simultaneously heats the flow and the dielectric surface. The thermal characteristics of the DBDPA must be clarified for applications in thermo-fluid engineering, such as forced convective cooling. In this study, we constructed a similarity law for the time variation of the surface temperature, assuming that the induced flow was heated by the discharge and that the dielectric was heated by the airflow. The similarity law was derived from the one-dimensional heat conduction equation in the dielectric, and the spatially averaged normalized temperature was then formulated as a function of the Biot and Fourier numbers. To experimentally validate the similarity law, the surface temperature, thrust, and power consumption were measured. The induced flow temperature and heat transfer coefficient were estimated based on the thrust and power consumption. The measured results verified that the similarity law was valid, regardless of the dielectric material, thickness, or applied voltage. This result supports the hypothesis regarding the heating mechanism in which the airflow is heated by Joule heating and the dielectric is heated by forced convection.
Structural properties of Bi/Au(110)
Authors: Neziri Egzona , Zhang Wei , Smogunov Alexander , Mayne Andrew J , Kara Abdelkader , Dappe Yannick J , Oughaddou Hamid
Published: February 2023

Atomically thin bismuth films (2D Bi) are becoming a promising research area due to their unique properties and their wide variety of applications in spintronics, electronic and optoelectronic devices. We report on the structural properties of Bi on Au(110), explored by low-energy electron diffraction (LEED), scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. At a Bi coverage lower than one monolayer (1 ML) various reconstructions are observed, we focus on Bi/Au(110)-c(2 × 2) reconstruction (at 0.5 ML) and Bi/Au(110)-(3 × 3) structure (at 0.66 ML). We propose models for both structures based on STM measurements and further confirm by DFT calculations.
A feasibility study of enhanced prompt gamma imaging for range verification in proton therapy using deep learning
Authors: Jiang Zhuoran , Polf Jerimy C , Barajas Carlos A , Gobbert Matthias K , Ren Lei
Published: February 2023

Background and objective. Range uncertainty is a major concern affecting the delivery precision in proton therapy. The Compton camera (CC)-based prompt-gamma (PG) imaging is a promising technique to provide 3D in vivo range verification. However, the conventional back-projected PG images suffer from severe distortions due to the limited view of the CC, significantly limiting its clinical utility. Deep learning has demonstrated effectiveness in enhancing medical images from limited-view measurements. But different from other medical images with abundant anatomical structures, the PGs emitted along the path of a proton pencil beam take up an extremely low portion of the 3D image space, presenting both the attention and the imbalance challenge for deep learning. To solve these issues, we proposed a two-tier deep learning-based method with a novel weighted axis-projection loss to generate precise 3D PG images to achieve accurate proton range verification. Materials and methods: the proposed method consists of two models: first, a localization model is trained to define a region-of-interest (ROI) in the distorted back-projected PG image that contains the proton pencil beam; second, an enhancement model is trained to restore the true PG emissions with additional attention on the ROI. In this study, we simulated 54 proton pencil beams (energy range: 75–125 MeV, dose level: 1 × 109 protons/beam and 3 × 108 protons/beam) delivered at clinical dose rates (20 kMU min−1 and 180 kMU min−1) in a tissue-equivalent phantom using Monte-Carlo (MC). PG detection with a CC was simulated using the MC-Plus-Detector-Effects model. Images were reconstructed using the kernel-weighted-back-projection algorithm, and were then enhanced by the proposed method. Results. The method effectively restored the 3D shape of the PG images with the proton pencil beam range clearly visible in all testing cases. Range errors were within 2 pixels (4 mm) in all directions in most cases at a higher dose level. The proposed method is fully automatic, and the enhancement takes only ∼0.26 s. Significance. Overall, this preliminary study demonstrated the feasibility of the proposed method to generate accurate 3D PG images using a deep learning framework, providing a powerful tool for high-precision in vivo range verification of proton therapy.
Phase-sensitive detection of anomalous diffusion dynamics in the neuronal membrane induced by ion channel gating
Authors: Choi Honggu , Iyer Rishyashring R , Renteria Carlos A , Boppart Stephen A
Published: February 2023

Non-ergodicity of neuronal dynamics from rapid ion channel gating through the membrane induces membrane displacement statistics that deviate from Brownian motion. The membrane dynamics from ion channel gating were imaged by phase-sensitive optical coherence microscopy. The distribution of optical displacements of the neuronal membrane showed a Lévy-like distribution and the memory effect of the membrane dynamics by the ionic gating was estimated. The alternation of the correlation time was observed when neurons were exposed to channel-blocking molecules. Non-invasive optophysiology by detecting the anomalous diffusion characteristics of dynamic images is demonstrated.
Quantum geometrical current and coherence of the open gravitation system: loop quantum gravity coupled with a thermal scalar field
Authors: Wang Hong , Wang Jin
Published: February 2023

Open quantum systems interacting with the environments often show interesting behaviors, such as decoherence, non-unitary evolution, dissipation, etc. It is interesting but still challenging to study the open quantum gravitation system interacting with the environments. In this work, we develop a general parameterized theoretical framework for the open quantum gravitation system. We studied a specific model where a real scalar field plays the role of the environment and the spacetime is assumed to be homogeneous and isotropic. We quantize the spacetime through the loop quantum gravity. We show that if the scalar field is in the thermal equilibrium state, the spacetime geometry will reach the equilibrium state after the transient relaxation. For the non-steady state, the quantum geometry current emerges. We point out that the quantum geometry current and the coherence can together drive the evolution of the spacetime geometry. This provides us a new view on the evolution of the spacetime geometry. Our results show that the coherence of the spacetime monotonically decreases as the temperature of the bath decreases. It helps the understanding of how a classical cold universe can emerge from an initial hot quantum universe.
Terahertz fiber with multi-concentric ring cores for OAM modes propagation
Authors: Yuan Yuan , Kong Depeng , Guan Lei , Wang Lili , Li Wenlong
Published: February 2023

A novel fiber incorporating central hollow, porous isolated layers, and concentric ring cores is proposed for the simultaneous propagation of multi-terahertz (THz) orbital angular momentum (OAM) modes with low-level inter-core and inter-mode crosstalk. The designed fiber can efficiently support 132 OAM modes in 0.6 ∼ 1.5 THz, 178 OAM modes in 0.7 ∼ 1.5 THz, etc, the high-order radial modes are suppressed within the whole frequency range meanwhile, and the number of OAM modes can be further boosted by further increasing the number of ring cores. In addition, the fiber has low confinement loss, flat dispersion, and high purity over a wide operating range. Hence it can be applied in mode-division multiplexing (MDM) based on OAM combined with core-division multiplexing (CDM) in THz range, and is also compatible with wavelength-division multiplexing (WDM) and multi-level modulation formats. The realized fiber is expected to dramatically extend the transmission capacity and spectral efficiency.
Fuzzy Yang transform for second order fuzzy differential equations of integer and fractional order
Authors: Ullah Abd , Ullah Aman , Ahmad Shabir , Van Hoa Ngo
Published: February 2023

In this work, a Laplace-like transform in a fuzzy environment called Yang transform is introduced to solve fuzzy differential equations (FDEs) with the order θ ∈ (1, 2] involving the Caputo fractional derivative in the sense of gH-differentiability. Some basic properties of Yang transform for integer and fractional derivatives are also provided. Furthermore, by utilizing the combination between the Adomian decomposition method (ADM) and the Yang transform method, a general algorithm called the hybrid Yang transform method (HYTM) to solve the solutions of FDEs in the nonlinear form is proposed. For the validity and accuracy of this novel method, some examples and their simulations are given.
Shift-symmetric Horndeski gravity in the asymptotic-safety paradigm
Authors: Eichhorn Astrid , Lino dos Santos Rafael R. , Wagner Fabian
Published: February 2023

Horndeski gravity is a popular contender for a phenomenological model of dynamical dark
energy, and as such subject to observational constraints. In this work, we ask whether Horndeski
gravity can be more than a phenomenological model and instead become a fundamental theory, which
extends towards high energy scales and includes quantum effects. We find that within the
asymptotic-safety paradigm, an ultraviolet completion of a simple class of models of Horndeski
gravity is achievable, but places strong constraints on the couplings of the theory. These
constraints are not compatible with dynamical dark energy. Further, we find a similar result in an
effective-field theory approach to this class of models of Horndeski gravity: under the assumption
that there is no new strongly-coupled physics below the Planck scale, quantum gravity fluctuations
force the Horndeski couplings to be too small to achieve an explanation of dynamical dark energy.
Correlation analysis of decaying sterile neutrino dark matter in the context of the SRG mission
Authors: Barinov V.V.
Published: February 2023

We provide a correlation analysis of signatures associated with traces of the dark matter decay and the galaxy spatial distribution according to the 2MRS catalog of galaxies. Signature data analysis plays an important role in the context of current and future observations and cosmological constraints. Attention is paid to the constraints that can be obtained for decaying sterile neutrinos when analyzing observations in the context of the Spectr-Roentegn-Gamma (SRG) mission. We study the correlation spectra of dark matter and galaxies, which can be obtained both for the eROSITA telescope and for the first time for the ART-XC telescope. The analysis is carried out both within the framework of the Limber approximation and within the framework of the extended Limber approximation, which makes it possible to more accurately study the power spectra in the region of small multipoles. We calculate the power spectra in both approaches and examine the contribution of different ranges of multipoles to the resulting constraints on sterile neutrino parameters.
The SNAD Viewer: Everything You Want to Know about Your Favorite ZTF Object
Authors: Malanchev Konstantin , Kornilov Matwey V. , Pruzhinskaya Maria V. , Ishida Emille E. O. , Aleo Patrick D. , Korolev Vladimir S. , Lavrukhina Anastasia , Russeil Etienne , Sreejith Sreevarsha , Volnova Alina A. , Voloshina Anastasiya , Krone-Martins Alberto
Published: February 2023

We describe the SNAD Viewer, a web portal for astronomers which presents a centralized view of individual objects from the Zwicky Transient Facility’s (ZTF) data releases, including data gathered from multiple publicly available astronomical archives and data sources. Initially built to enable efficient expert feedback in the context of adaptive machine learning applications, it has evolved into a full-fledged community asset that centralizes public information and provides a multi-dimensional view of ZTF sources. For users, we provide detailed descriptions of the data sources and choices underlying the information displayed in the portal. For developers, we describe our architectural choices and their consequences such that our experience can help others engaged in similar endeavors or in adapting our publicly released code to their requirements. The infrastructure we describe here is scalable and flexible and can be personalized and used by other surveys and for other science goals. The Viewer has been instrumental in highlighting the crucial roles domain experts retain in the era of big data in astronomy. Given the arrival of the upcoming generation of large-scale surveys, we believe similar systems will be paramount in enabling an optimal exploitation of the scientific potential enclosed in current terabyte and future petabyte-scale data sets. The Viewer is publicly available online at https://ztf.snad.space.
Influence of thickness on tunability performance of plasma sputtered indium tin oxide as Q-switcher
Authors: Zalkepali N U H H , Mahmud N N H E N , Awang N A , Muhammad N A M , Zamri A Z M
Published: February 2023

We successfully investigated the influence of thickness on the tunability performance of plasma-sputtered indium tin oxide (ITO) as a Q-switcher. ITO is coated using direct current magnetron sputtering techniques with sputtering times of 150 s, 250 s, and 350 s to generate excellent quality ITO. Filmetrics measures the thickness, yielding 17.80 nm, 30.70 nm, and 38.90 nm, respectively. A stable Q-switched pulse is achieved at an operating wavelength and peak power of 1562.30 nm and −6.47 dBm for the thickness of 17.80 nm, 1561.40 nm and −3.19 dBm for the thickness of 30.70 nm, and 1560.2 nm and −2.44 dBm for the thickness of 38.90 nm. The thickness of 38.90 nm exhibit a high repetition rate of 43.60 kHz and narrow pulse width of 4.83 µs compared to other thickness. Employing the tunable bandpass filter in the laser ring cavity gives the wide-tuning of the wavelength range of 19.69 nm, 31.86 nm, and 36.59 nm for the thickness of 17.80 nm, 30.70 nm, and 38.90 nm, respectively. The tunability of Q-switched with the thicknesses of 30.70 nm and 38.90 nm is realized in the region of C-band to L-band. Regarding the authors’ expertise, this seems to be the first proposed influence of thickness on the tunability of plasma sputtered ITO that serves as saturable absorber in a Q-switched pulse.
Tuning of optical fiber laser based on super-mode interference in a seven-core fiber
Authors: Vallejo-Carrillo R G , Salceda-Delgado G , Torres-Torres M , Amezcua-Correa R , Antonio-Lopez J E
Published: February 2023

Tuning of optical fiber laser emissions based on super-mode interference in a seven core fiber (SCF) is presented. This super-mode interference is generated by a super-mode Mach–Zehnder interferometer constructed with a few millimeters of SCF spliced between two single mode fibers (SMFs). In the SCF, two super-modes are exited via the fundamental mode of the SMF. Then, an interference pattern caused to the optical path difference between super-modes is generated at the final of the SCF, which is collected with the spliced SMF. This interference pattern induces and tunes laser line emissions by adjusting the laser cavity losses in an optical fiber laser. By bending the Mach–Zehnder interferometer, a wavelength shift of the interference pattern is induced, which in turn causes a wavelength shift of the laser cavity losses and, therefore, a displacement of the laser wavelength emission. Laser line emissions were tuned by linear factors of around 0.91 nm mm−1, and the switching of simultaneous emissions was also obtained. The stability and reliability of the laser emission on the proposed method are also discussed.
Optical encryption scheme based on spread spectrum ghost imaging
Authors: Liu Jin-Fen , Dong Yue , Wang Le , Zhao Sheng-Mei
Published: February 2023

An optical encryption (OE) scheme based on the spread spectrum ghost imaging (SSGI), named as SSGI-OE, is proposed to obtain a high security with a smaller key. In the scheme, the randomly selected row number of a Hadamard matrix of order N is used as the secure key, and shared with the authorized user, Bob, through a private channel. Each corresponding row vector of the order-N Hadamard matrix is then used as the direct sequence code to modulate a speckle pattern for the ghost imaging system, and an image is encrypted with the help of the SSGI. The measurement results from the bucket detector, named as ciphertext, are then transmitted to Bob through a public channel. The illuminating speckle patterns are also shared with Bob by the public channel. With the correct secure key, Bob could reconstruct the image with the aid of the SSGI system, whereas the unauthorized user, Eve, could not obtain any useful information of the encrypted image. The numerical simulations and experimental results show that the proposed scheme is feasible with a higher security and a smaller key. For the 32 × 32 pixels image, the number of bits sent from Alice to Bob by using SSGI-OE (M = 1024, N = 2048) scheme is only 0.0107 times over a computational ghost imaging optical encryption scheme. When the eavesdropping ratio (ER) is less than 40%, the eavesdropper cannot acquire any information of the encrypted image. The extreme circumstance for the proposed SSGI-OE scheme is also discussed, where the eavesdropper begins to extract the information when ER is up to 15%.
Effects of atomic corrugations on electronic structures in Pb1−x
Bi
x
thin films
Authors: Li Pengju , Xie Kun , Xia Yumin , Cai Desheng , Qin Shengyong
Published: February 2023

We carried out experimental investigations of the geometric effect on the electronic behavior in Pb1−x
Bi
x
thin films by scanning tunneling microscopy and spectroscopy. Single crystal monolayer Pb0.74Bi0.26 and two-monolayer Pb0.75Bi0.25 Pb1−x
Bi
x
thin films were fabricated by molecular beam epitaxy, where large surface corrugations were observed. Combined with tunneling spectroscopic measurements, it is found that atomic corrugations can widely change the electronic behaviors. These findings show that the Pb1−x
Bi
x
system can be a promising platform to further explore geometry-decorated electronic behavior in two-dimensional metallic thin films.
Modeling extracellular stimulation of retinal ganglion cells: theoretical and practical aspects
Authors: Kish Kathleen E , Lempka Scott F , Weiland James D
Published: February 2023

Objective. Retinal prostheses use electric current to activate inner retinal neurons, providing artificial vision for blind people. Epiretinal stimulation primarily targets retinal ganglion cells (RGCs), which can be modeled with cable equations. Computational models provide a tool to investigate the mechanisms of retinal activation, and improve stimulation paradigms. However, documentation of RGC model structure and parameters is limited, and model implementation can influence model predictions. Approach. We created a functional guide for building a mammalian RGC multi-compartment cable model and applying extracellular stimuli. Next, we investigated how the neuron’s three-dimensional shape will influence model predictions. Finally, we tested several strategies to maximize computational efficiency. Main results. We conducted sensitivity analyses to examine how dendrite representation, axon trajectory, and axon diameter influence membrane dynamics and corresponding activation thresholds. We optimized the spatial and temporal discretization of our multi-compartment cable model. We also implemented several simplified threshold prediction theories based on activating function, but these did not match the prediction accuracy achieved by the cable equations. Significance. Through this work, we provide practical guidance for modeling the extracellular stimulation of RGCs to produce reliable and meaningful predictions. Robust computational models lay the groundwork for improving the performance of retinal prostheses.
Cosmic muon tomography at the Wylfa reactor site utilising an anti-neutrino detector
Authors: Bridges K. , Coleman J. , Collins R. , Dasari J. , Holt G. , Metelko C. , Morgan A. , Murdoch M. , Schnellbach Y. , Tsurin I. , Mills R.W. , Ryan M. , Edwards G. , Roberts A.
Published: February 2023

An anti-neutrino detector (a prototype of VIDARR) was
deployed at the Wylfa Magnox nuclear power station between 2014 and
2016. It was comprised of extruded plastic scintillating bars
measuring 4 cm by 1 cm by 152 cm and utilised wavelength
shifting fibres (WLS) and Multi-Pixel Photon Counters (MPPCs) to
detect and quantify radiation. During deployment, the detector
recorded cosmic muon events in accidental coincidence along with the
anti-neutrino events. The cosmic muons produced in the upper
atmosphere had their paths obscured by the power plant buildings as
the cosmic muons originated behind the buildings. Cosmic muons have
a significantly higher probability to be attenuated and/or absorbed
by denser objects and so one-sided muographic methods were utilised
to image the reactor site buildings. In order to achieve clear
building outlines a control data set was taken at the University of
Liverpool from 2016 to 2018 which had minimal occlusion of the
cosmic muon flux by dense objects. By taking the ratio of these two
data sets and using GEANT4 simulations it is possible to perform a
one-sided cosmic muon tomography analysis. This analysis can be used
to discern specific buildings, building heights, and features at the
Wylfa reactor site including the reactor core/reactor core shielding
using cosmic-ray events equivalent to that which would be seen in
∼ 3 hours of normal operation. This result demonstrates the
feasibility of using cosmic muon analysis to determine a segmented
detector's location with respect to surrounding buildings, assisted
by aerial photography or satellite imagery.
Contrasting trends in short-lived and long-lived mesoscale eddies in the Southern Ocean since the 1990s
Authors: Shi Fei , Luo Yiyong , Wu Renhao , Yang Qinghua , Chen Ruiyi , Wang Chuanyin , Lin Yichen , Chen Dake
Published: February 2023

Mesoscale eddies play an important role in the transport of heat, carbon, and nutrients in the Southern Ocean. Previous studies have documented an increasing intensity of the Southern Ocean eddy field during recent decades; however, it remains unclear whether the mesoscale eddies with different lifetimes have different temporal variations. Using satellite altimeter observations from 1993 to 2020, we found that the increasing trend in the intensity of eddies is dominated by long-lived eddies (with lifetimes ⩾ 90 d), whose amplitude has increased at a rate of ∼2.8% per decade; the increase is concentrated downstream of topography. In contrast, short-lived eddies (with lifetimes < 90 d) do not appear to have a significant trend in their amplitudes since the early 1990s. An energy conversion analysis indicates that the increased baroclinic instabilities of the mean flows associated with topography are responsible for the amplitude increase of the long-lived eddies. This study highlights the need for a better understanding of the changes in mesoscale eddies owing to their importance in the transport of heat, carbon, and nutrients.
A new mathematical model of rigid boundary in shear flows
Authors: Chanishvili R , Chagelishvili G , Kalashnik M , Chkhetiani O , Gogichaishvili D , Kharshiladze O
Published: February 2023

The present investigation is devoted to the revealing of the physical essence of the action of the rigid boundary on the linear dynamics of perturbations in plane shear flows. A new mathematical approach is proposed which accurately and completely replaces the horizontal rigid boundary by the actions of certain localized sources placed on the plane of the boundary (z = 0) in the original/canonical shear flow dynamical equations for wave and vortex mode perturbations, i.e. for perturbations with zero and nonzero potential vorticity. The approach is elaborated on the example of the well-known problem of geophysical hydrodynamics—the linear dynamics of perturbations in semi-infinite (

z
⩾
0

) flow of stratified rotating fluid with a vertical shear of velocity,

{U}

0

(
A
z
,
0
,
0
)

, zero beta, β = 0, and horizontal rigid boundary at z = 0—which analytical wave and vortex mode solutions are well-known and serve as the reference solutions of our model equations. From the beginning, we have replaced the rigid boundary with localized sources for vortices and wave modes separately. The sources are the sum of the delta function and its first derivative the coefficients in front of which were unknown at this stage. In what follows, we accurately calculated these coefficients and thus determined the exact expressions for localized sources. Subsequent mathematical analysis showed that the localized sources give rise to new perturbations which can be labeled as secondary. The revealed physical essence of the action of the rigid boundary is as follows: being the external (localized) source of the analyzed open complex flow system, the rigid boundary puts an additional energy into perturbation harmonics that becomes an important power supplier supporting the linear dynamics of the system under study. Namely, the rigid boundary rearranges the vortex component via exciting new/secondary perturbations, which, superimposing with the main/primary perturbations of the flow, ensures zeroing of perturbations in the area z < 0 and, at the same time, provides the growth of the wave component in the area

z
⩾
0

coinciding with the well-known analytical solution of the canonical approach. From a general point of view, the following is important: In the existing/classical trend of studying the dynamics of perturbations in bounded shear flows, the actions of the flow boundary/boundaries and the flow shear are not delimited from each other. Whereas, the proposed new mathematical approach delimits them highlighting the action of the boundary on the linear dynamics of wave and vortex modes of perturbations.
Stochastic geometric mechanics in nonequilibrium thermodynamics: Schrödinger meets Onsager
*
Authors: Huang Qiao , Zambrini Jean-Claude
Published: February 2023

We are describing relations between Schrödinger’s variational problem and Onsager’s approach to nonequilibrium statistical mechanics. Although the second work on reciprocal relations and detailed balance has been published in the same year (1931) as the first one, the impact of Schrödinger’s idea has not yet been considered in the classical context of Onsager.
Production of biocoke from microalgae powder
Authors: Ang X Y , Koesoemadinata V C , Md Khudzari J , Abdullah N , Iwamoto K
Published: February 2023

Biocoke has been invented to replace commercial coke in order to reduce the consumption of fossil fuels. However, the main target of the feedstock has been limited to plant and wood biomass, while algal biomass is rarely used. This work evaluated four microalgae species: Chlorella, Nannochloropsis, Diatoms, and Aurantiochytrium as the feedstocks to produce biocokes. The production of the biocoke was set to 100°C at 20 MPa for 6 mins 20 secs. Based on visual observation, the color of the biocokes produced was darker than the microalgae powder due to the Maillard reaction. This study suggested that the Chlorella and Nannochloropsis biocoke have the potential to produce the biocoke due to their oleaginous characteristic. Nannochloropsis had a higher apparent density than Chlorella biocoke. However, the Chlorella had a higher compression strength of 37.55MPa, compared to Nannochloropsis (27.70MPa). Meanwhile, Aurantiochythrium biocoke had an irregular shape and was sticky due to the high lipid content in the species. The Diatoms biocoke was hard but chalky due to its silica shell on the microalgae cell. Therefore, the Aurantiochythrium and Diatoms were not suitable for producing the biocokes.
Extraction and determination of flavonoid compounds in citrus fruit waste
Authors: Rushdan Zaim I N , Wahab M , Ismail H F , Othman N , Hara H , Md Akhir F N
Published: February 2023

Citrus is a globally cultivated fruit crop that has been heavily industrialised to manufacture food products. It is commonly sought out for its nutritional benefits. However, parallel to rapid industrialisation, parts of the crop’s physical composition (inner and outer peel, seeds etc.) are often discarded to the environment as waste. Recent advancement in technology has led researchers to look for alternatives to recover potential therapeutic compounds from citrus fruit waste, directly extending the life of the waste and indirectly solving waste management concerns. Citrus fruit peels are especially rich in flavonoid compounds, a subclass of the many phytochemicals largely present in the body of the fruit. Flavonoid compounds have the capacity to be act as antioxidants, leaving room for the potential of the flavonoids present in fruit waste to be commercialized as a natural bioresource. This study aims to extract and recover the flavonoid compounds present in the peels of citrus fruits calamansi (Citrus microcarpa), kaffir lime (Citrus hystrix), and key lime (Citrus aurantiifolia) via ethanolic extraction and test the presence of recovered flavonoid compounds via alkaline reagent test. In addition, this study also aims to measure the antioxidant activities of all three citrus fruit peel samples via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. This study hopes to shed light on the therapeutic potential of citrus fruit peel waste as a bioresource which could benefit communities in the future.
Analysis of suspended atmospheric microplastics size at different elevation in Universiti Teknologi Malaysia, Kuala Lumpur
Authors: Afiq Daniel Azmi M , Yasin N L N M , NorRuwaida J , Hasnatul A H , Dewika M , Sara Y Y
Published: February 2023

Atmospheric microplastics can be found in the atmospheres of urban, suburban, and even remote locations. To date, limited studies have been done in investigating the microplastics contamination at different elevation. In this regard, suspended atmospheric microplastics were sampled at two different elevations in Universiti Teknologi Malaysia, Kuala Lumpur. The sampling was done using SIBATA High-Volume Sampler HV-1000R pump for 24 hours sampling, twice a week for 10 weeks. The primary objective of this research is to analyze the size of the suspended atmospheric microplastics at different elevation which is ground level (H1) at1.5m and upper level (H2) at 10m. The finding shows that the range size of the microplastics at H1 is between 70 to 1855 μm and H2 is 102 to 5429 μm indicate that the microplastics size at higher elevation is larger compared to the lower ground. The range abundance of microplastic is also discussed where it is between 97 to 775 particle/m2/day, with the particulate concentration ranging from 16.39 to 96.81 μg/m3/day for both locations. The EDI indicate that children are much more exposed to polymer-based MPs by dust consumption than teenagers and adults, with 4.6 particle/kg.day at H1 and 3.4 particle/kg.day at H2.
Flood preparedness module for Malaysian Higher Education students via Metaverse Environment
Authors: Sa don N F , Sa don H S , Alias R A , Nakanishi H
Published: February 2023

In Malaysia, the severity of natural disasters such as floods, landslides, and earthquakes have increased in recent years, making disaster preparedness a crucial aspect of students’ lives. In the context of flood preparedness, accessibility to materials on flood is still in deficit and a future-ready learning approach is required. This is parallel to Sustainable Development Goals Goal 4 in promoting lifelong learning opportunities for all. The objective of this research is twofold: to study flood preparedness among Malaysian higher education students and to propose a flood preparedness module for Malaysian higher education students via Metaverse environment. The module is developed using Spatial.io, an immersive shared AR platform. For this research, the module addresses flood which is presented via a 3-D virtual learning space. This beta version will opt for multiple-stage sampling method via a focus group comprising 10 PPSSAAS students. Then, UX Testing, and post-test are conducted to gauge the module usability and latent potentials. Based on the research, the use of metaverse for the flood preparedness module shows significant impact amongst the respondents. The finding from this research is hoped to enhance students’ knowledge and awareness of flood preparedness so students can care for themselves and be of help to others during an emergency.
Assessment of peat fire susceptibility for carbon emission reduction
Authors: Ahmad Nizam M A H , Mat Taib S , Mohd Yunus N Z , Saman N
Published: February 2023

This paper aims are; a) to identify the peat classification based on peat depth and groundwater level; b) to identify CO2 content stored and CO2 emission of peat within the study area; c) to produce a hotspot hazard map using Analytical Hierarchy Process (AHP) and geospatial technologies. These are vital components in producing a holistic peat fire management approach. Based on the site works, the majority of the peat within the area is classified as Sapric (low fibre content) using the Von Post Classification System, with an average peat thickness of 0.65m at a maximum depth of 1.2m and average groundwater level of 0.67m. On the other hand, soil samples were collected on-site and tested, indicating an average organic and fibre contents of 45.24% and 37% respectively, with a bulk density of 1.03 Mg/m3. The average carbon content was 30.29 carbon tonne/hectare, hence having the potential to release 381,925.18 tonnes of CO2 annually (tCO2/year). Finally, potential peat fire susceptible areas were classified and visualized on a hotspot hazard map utilizing the data acquired. It can be concluded that continued development without considering appropriate mitigation measures will potentially increase the feasibility of peat ignition, thus, increasing overall carbon emission significantly.
Current biofabrication methods for vascular tissue engineering and an introduction to biological textiles
Authors: Kawecki Fabien , L’Heureux Nicolas
Published: February 2023

Cardiovascular diseases are the leading cause of mortality in the world and encompass several important pathologies, including atherosclerosis. In the cases of severe vessel occlusion, surgical intervention using bypass grafts may be required. Synthetic vascular grafts provide poor patency for small-diameter applications (< 6 mm) but are widely used for hemodialysis access and, with success, larger vessel repairs. In very small vessels, such as coronary arteries, synthetics outcomes are unacceptable, leading to the exclusive use of autologous (native) vessels despite their limited availability and, sometimes, quality. Consequently, there is a clear clinical need for a small-diameter vascular graft that can provide outcomes similar to native vessels. Many tissue-engineering approaches have been developed to offer native-like tissues with the appropriate mechanical and biological properties in order to overcome the limitations of synthetic and autologous grafts. This review overviews current scaffold-based and scaffold-free approaches developed to biofabricate tissue-engineered vascular grafts (TEVGs) with an introduction to the biological textile approaches. Indeed, these assembly methods show a reduced production time compared to processes that require long bioreactor-based maturation steps. Another advantage of the textile-inspired approaches is that they can provide better directional and regional control of the TEVG mechanical properties.
Fabrication and multi- performance optimization of mechanical properties of novel Babbitt-Ilmenite metal matrix composite using entropy based hybrid Taguchi-grey relational analysis
Authors: Wadhwa Amandeep Singh , Chauhan Amit
Published: February 2023

In the present study, a Babbitt-Ilmenite composite was developed via stir casting and the mechanical properties (hardness and tensile strength) of the composite were optimized using the Taguchi philosophy. The effects of variations in the percentage weight of Ilmenite, stirring speed and aging time on the mechanical properties of the composite were studied. Energy dispersive spectroscopy analysis confirmed the presence of Ilmenite in the metal matrix and uniform dispersal of Ilmenite in Babbitt was established via scanning electron microscopy. A Morphological analysis of the fractured tensile specimen was conducted to ascertain the type of failure. The Taguchi methodology and analysis of variance technique were proposed to predict the optimum levels of controllable parameters and to determine their percentage contribution to the optimization of mechanical properties of the composite. The percentage weight of Ilmenite and stirring speed were found to have significant effect on hardness while aging time was a significant parameter for the tensile strength of the composite. The predicted results were validated by confirmation experiments with a deviations of 1.6% and 2.1% for hardness and tensile strength respectively for single objective optimization. The weights of the responses were determined objectively and the multi-performance optimization of mechanical properties of the composite was performed using entropy based grey relational analysis (EGRA). The percentage weight of Ilmenite was only significant parameter with contribution of 30.65% for multi-performance optimization of mechanical attributes of composite using hybrid Taguchi grey relation analysis (TGRA). An overall improvement of 0.445 and 0.105 in the grey relation grade was reported using EGRA and TGRA respectively. The study concludes that the Babbitt/Ilmenite composite has superior mechanical properties both for single and multi-objective optimized conditions than the unreinforced tin Babbitt. The developed composite can be used for bearings in crankshafts, connecting rods and axles of automobiles.
Massive increases in C31 alkane on Zygophyllum xanthoxylum leaves contribute to its excellent abiotic stress tolerance
Authors: Li Hu-Jun , Bai Wan-Peng , Liu Lin-Bo , Liu Hai-Shuang , Wei Li , Garant Timothy M , Kalinger Rebecca S , Deng Yu-Xuan , Wang Gai-Ni , Bao Ai-Ke , Ma Qing , Rowland Owen , Wang Suo-Min
Published: February 2023

Background and Aims

Desert plants possess excellent water-conservation capacities to survive in extreme environments. Cuticular wax plays a pivotal role in reducing water loss through plant aerial surfaces. However, the role of cuticular wax in water retention by desert plants is poorly understood.

Methods

We investigated leaf epidermal morphology and wax composition of five desert shrubs from north-west China and characterized the wax morphology and composition for the typical xerophyte Zygophyllum xanthoxylum under salt, drought and heat treatments. Moreover, we examined leaf water loss and chlorophyll leaching of Z. xanthoxylum and analysed their relationships with wax composition under the above treatments.

Key Results

The leaf epidermis of Z. xanthoxylum was densely covered by cuticular wax, whereas the other four desert shrubs had trichomes or cuticular folds in addition to cuticular wax. The total amount of cuticular wax on leaves of Z. xanthoxylum and Ammopiptanthus mongolicus was significantly higher than that of the other three shrubs. Strikingly, C31 alkane, the most abundant component, composed >71 % of total alkanes in Z. xanthoxylum, which was higher than for the other four shrubs studied here. Salt, drought and heat treatments resulted in significant increases in the amount of cuticular wax. Of these treatments, the combined drought plus 45 °C treatment led to the largest increase (107 %) in the total amount of cuticular wax, attributable primarily to an increase of 122 % in C31 alkane. Moreover, the proportion of C31 alkane within total alkanes remained >75 % in all the above treatments. Notably, the water loss and chlorophyll leaching were reduced, which was negatively correlated with C31 alkane content.

Conclusion

Zygophyllum xanthoxylum could serve as a model desert plant for study of the function of cuticular wax in water retention because of its relatively uncomplicated leaf surface and because it accumulates C31 alkane massively to reduce cuticular permeability and resist abiotic stressors.