bluuebunny/crossref_metadata_2025 huggingface dataset:
Leading-edge-vortex tailoring on unsteady airfoils using an inverse aerodynamic approach
Authors: Suresh Babu Arun Vishnu , Narsipur Shreyas , Bryant Matthew , Gopalarathnam Ashok
Published: May 2022

In this paper, we present an approach to obtain a desired leading-edge vortex (LEV) shedding pattern from unsteady airfoils through the execution of suitable motion kinematics. Previous research revealed that LEV shedding is associated with the leading-edge suction parameter (LESP) exceeding a maximum threshold. A low-order method called LESP-modulated discrete vortex method (LDVM) was also developed to predict the onset and termination of LEV shedding from an airfoil undergoing prescribed motion kinematics. In the current work, we present an inverse-aerodynamic formulation based on the LDVM to generate the appropriate motion kinematics to achieve a prescribed LESP variation, and thus, the desired LEV shedding characteristics from the airfoil. The algorithm identifies the kinematic state of the airfoil required to attain the target LESP value through an iterative procedure performed inside the LDVM simulation at each time step. Several case studies are presented to demonstrate design scenarios such as tailoring the duration and intensity of LEV shedding, inducing LEV shedding from the chosen surface of the airfoil, promoting or suppressing LEV shedding during an unsteady motion on demand, and achieving similar LEV shedding patterns using different maneuvers. The kinematic profiles generated by the low-order formulation are also simulated using a high-fidelity unsteady Reynolds-averaged Navier–Stokes method to confirm the accuracy of the low-order model.
Magnetic moments and spin structure in single-phase B20 Co1+xSi1−x (x = 0.043)
Authors: Wang Haohan , Balasubramanian Balamurugan , Liu Yaohua , Streubel Robert , Pahari Rabindra , Ekanayaka Thilini Kumari , Mishra Esha , Klewe Christoph , Shafer Padraic , Dhall Rohan , Skomski Ralph , Sellmyer David J. , Xu Xiaoshan
Published: May 2022

Neutron powder diffraction (NPD) and x-ray magnetic circular dichroism (XMCD) spectroscopy are employed to investigate the magnetism and spin structure in single-phase B20 Co1.043Si0.957. The magnetic contributions to the NPD data measured in zero fields are consistent with the helical order among the allowed spin structures derived from group theory. The magnitude of the magnetic moment is (0.3 ± 0.1)μB/Co according to NPD, while the surface magnetization probed by XMCD at 3 kOe is (0.18–0.31)μB/Co. Both values are substantially larger than the bulk magnetization of 0.11μB/Co determined from magnetometry at 70 kOe and 2 K. These experimental data indicate the formation of a helical spin phase and the associated conical states in high magnetic fields.
H trapping at the metastable cation vacancy in α-Ga2O3 and α-Al2O3
Authors: Venzie Andrew , Portoff Amanda , Stavola Michael , Fowler W. Beall , Kim Jihyun , Jeon Dae-Woo , Park Ji-Hyeon , Pearton Stephen J.
Published: May 2022

α-Ga2O3 has the corundum structure analogous to that of α-Al2O3. The bandgap energy of α-Ga2O3 is 5.3 eV and is greater than that of β-Ga2O3, making the α-phase attractive for devices that benefit from its wider bandgap. The O–H and O–D centers produced by the implantation of H+ and D+ into α-Ga2O3 have been studied by infrared spectroscopy and complementary theory. An O–H line at 3269 cm−1 is assigned to H complexed with a Ga vacancy (VGa), similar to the case of H trapped by an Al vacancy (VAl) in α-Al2O3. The isolated VGa and VAl defects in α-Ga2O3 and α-Al2O3 are found by theory to have a “shifted” vacancy-interstitial-vacancy equilibrium configuration, similar to VGa in β-Ga2O3, which also has shifted structures. However, the addition of H causes the complex with H trapped at an unshifted vacancy to have the lowest energy in both α-Ga2O3 and α-Al2O3.
Cellular perception of growth rate and the mechanistic origin of bacterial growth law
Authors: Wu Chenhao , Balakrishnan Rohan , Braniff Nathan , Mori Matteo , Manzanarez Gabriel , Zhang Zhongge , Hwa Terence
Published: May 2022

Significance

Cell signaling involves interpreting information from the environment and implementing the appropriate regulatory control. The ppGpp signaling system is known to exert a fundamental control in bacteria, coordinating ribosome synthesis with the rate of cellular growth, but how this system can sense the cellular growth rate in different environments is unclear. Here we establish a striking linear relation between ppGpp level and the reciprocal of the translation elongation rate (ER) and show how bacteria can process complex nutritional information by monitoring this rate and using it to control ribosome synthesis. Importantly, the sensing of ER through ppGpp quantitatively and mechanistically explains bacterial growth laws which robustly relate the ribosome content and translation ERs to the growth rate.
Digital rheometer twins: Learning the hidden rheology of complex fluids through rheology-informed graph neural networks
Authors: Mahmoudabadbozchelou Mohammadamin , Kamani Krutarth M. , Rogers Simon A. , Jamali Safa
Published: May 2022

Significance

Science-based data-driven methods that can describe the rheological behavior of complex fluids can be transformative across many disciplines. Digital rheometer twins, which are developed here, can significantly reduce the cost, time, and energy required to characterize complex fluids and predict their future behavior. This is made possible by combining two different methods of informing neural networks with the rheological underpinnings of a system, resulting in quantitative recovery of a gel’s response to different flow protocols. The platform developed here is general enough that it can be extended to areas well beyond complex fluids modeling.
Beyond monolithic English
Authors: Bagni Marco , Sumra Zeenat
Published: May 2022

The Global Englishes Language Teaching (GELT) paradigm has recently emerged as a comprehensive approach that aims
to bring together innovative pedagogical proposals. This paper argues that pop culture materials such as telecinematic
representations can purposefully be integrated into innovative GELT-oriented classroom practices. The use of this material can
assist teachers in the double task of (i) raising the learners’ critical awareness of sociolinguistic variation and problematizing
the stereotypical image of monolithic English; (ii) shifting the focus of the ELT classroom from prescriptive grammar and standard
English towards fostering the learners’ receptive and communicative skills. This is a conceptual paper that gives several broad
suggestions as to how to adopt pop culture materials into innovative GELT-oriented classroom practice and mentions a select few
examples of said telecinematic representations.
Corrosion resistance of niobium-added slag-free self-shielded flux-cored welding overlay in neutral solution
Authors: Liu Dashuang , Wei Ping , Wu Yucheng , Long Weimin , Wang Rui
Published: May 2022

The niobium-added iron-based slag-free self-shielded flux-cored wire was developed and the effect of niobium addition on the corrosion resistance in neutral pH solution was investigated. The carbides, including NbC carbides, primary (Cr, Fe)7C3, and eutectic (Cr, Fe)3C carbides, remain intact after neutral corrosion, but the grain interface is corroded preferably for all the niobium-added welding overlays. The eutectic microstructure of 7.2 wt-% niobium-added welding overlay, which has more grain interface, leads to severe corrosion. When niobium addition reaches 14.4 wt-%, the welding overlay possesses the best corrosion resistance since more NbC carbides are formed, prophase austenite dendrite is precipitated, decreasing the grain interface, and chromium content is increased in the matrix of the hypoeutectic microstructure.
DCs at the center of help: Origins and evolution of the three-cell-type hypothesis
Authors: Wu Renee , Murphy Kenneth M.
Published: May 2022

Last year was the 10th anniversary of Ralph Steinman’s Nobel Prize awarded for his discovery of dendritic cells (DCs), while next year brings the 50th anniversary of that discovery. Current models of anti-viral and anti-tumor immunity rest solidly on Steinman’s discovery of DCs, but also rely on two seemingly unrelated phenomena, also reported in the mid-1970s: the discoveries of “help” for cytolytic T cell responses by Cantor and Boyse in 1974 and “cross-priming” by Bevan in 1976. Decades of subsequent work, controversy, and conceptual changes have gradually merged these three discoveries into current models of cell-mediated immunity against viruses and tumors.
Role of adipose tissue macrophages in obesity-related disorders
Authors: Chakarov Svetoslav , Blériot Camille , Ginhoux Florent
Published: May 2022

The obesity epidemic has led researchers and clinicians to reconsider the etiology of this disease and precisely decipher its molecular mechanisms. The excessive accumulation of fat by cells, most notably adipocytes, which play a key role in this process, has many repercussions in tissue physiology. Herein, we focus on how macrophages, immune cells well known for their tissue gatekeeping functions, assume fundamental, yet ill-defined, roles in the genesis and development of obesity-related metabolic disorders. We first discuss the determinants of the biology of these cells before introducing the specifics of the adipose tissue environment, while highlighting its heterogeneity. Finally, we detail how obesity transforms both adipose tissue and local macrophage populations. Understanding macrophage diversity and their cross talk with the diverse cell types constituting the adipose tissue environment will allow us to frame the therapeutic potential of adipose tissue macrophages in obesity.
Drug development challenges in nontuberculous mycobacterial lung disease: TB to the rescue
Authors: Dartois Véronique , Dick Thomas
Published: May 2022

Nontuberculous mycobacterial pulmonary disease (NTM-PD) is treated with multiple repurposed drugs. Chemotherapy is long and often toxic, includes parenteral drugs, and suffers from poor cure rates. There is an urgent need for more efficacious, tolerated, and oral antibiotics optimized towards the treatment of NTM-PD, adapted to the spectrum of disease. In contrast to the empty NTM pipeline, drug development for the related tuberculosis lung disease has experienced a renaissance. Here, we argue that applying lessons learned from tuberculosis will facilitate the discovery of curative oral regimens for NTM-PD.
Bloch oscillations in supersolids
Authors: Hasan Muhammad S , Polo J , Pelayo J C , Busch Th
Published: May 2022

We show that the motion of an accelerated atomic impurity immersed in a spin–orbit coupled Bose–Einstein condensate in the supersolid stripe phase undergoes oscillations, similar to the well-known phenomenon of Bloch oscillations in solids. While the back-action of the oscillatory movement onto the condensate excites phonon modes inside the supersolid, it does not affect the position of the roton minimum and therefore not the periodicity of the matter wave lattice. The ultimate decay of the oscillations is mostly due to the dispersion of the wavepacket and we show that this can be counteracted to a large extent by assuming that the impurity is a bright soliton.
Research on remaining useful life of rolling bearings using EWT-DI-ALSTM
Authors: Guo Runxia , Gong Bo
Published: May 2022

The bearing is one of the most essential parts of rotating machinery and equipment, and the accurate prediction of the remaining useful life (RUL) of the bearing is of great engineering significance. This paper proposes a novel hybrid prediction architecture called the long short-term memory (LSTM) based on an attention mechanism combined with empirical wavelet transform (EWT) to improve the prediction accuracy of the RUL of bearings. The prediction architecture consists of three parts: firstly, the vibration signal of the bearing is stationarily processed into several intrinsic mode functions (IMFs) by EWT decomposition. Then, a novel IMF degradation index based on weighted energy entropy and the variance contribution rate is proposed to select the representative IMFs with more degradation characteristics of the bearing. Finally, the selected IMFs are regarded as inputs for the network model, and the LSTM network model based on the attention mechanism is used to track the degradation state of the bearing and accurately used to predict its remaining life. The effectiveness of the proposed method is demonstrated by the experimental data.
Preparation and characterization of non-aromatic ether self-assemblies on a HOPG surface
Authors: Alić Jasna , Biljan Ivana , Štefanić Zoran , Šekutor Marina
Published: May 2022

On-surface self-assemblies of aromatic organic molecules have been widely investigated, but the characterization of analogous self-assemblies consisting of fully sp3-hybridized molecules remains challenging. The possible on-surface orientations of alkyl molecules not exclusively comprised of long alkyl chains are difficult to distinguish because of their inherently low symmetry and non-planar nature. Here, we present a detailed study of diamondoid ethers, structurally rigid and fully saturated molecules, which form uniform 2D monolayers on a highly oriented pyrolytic graphite (HOPG) surface. Using scanning tunneling microscopy, various computational tools, and x-ray structural analysis, we identified the most favorable on-surface orientations of these rigid ethers and accounted for the forces driving the self-organization process. The influence of the oxygen atom and London dispersion interactions were found to be responsible for the formation of the observed highly ordered 2D ether assemblies. Our findings provide insight into the on-surface properties and behavior of non-aromatic organic compounds and broaden our understanding of the phenomena characteristic of monolayers consisting of non-planar molecules.
Development of counterintuitive basic electric DC circuits test
Authors: Balta Nuri , Logman Paul S W M
Published: May 2022

The purpose of this study is to develop a test to assess students’ level of counterintuitiveness in basic electric circuits. Data from four samples were gathered and used to develop and validate the counterintuitive basic electric circuit test (CBECT). The initial version of the CBECT was administered to the first sample and data collected from this sample were used for the pilot study. The aim of the data collected from the second sample was to comb out the items that were not counterintuitive. The data collected from the third sample were used for concurrent validity issues while data from the fourth sample was used for the test-retest reliability analysis. Finally, 26 items that can be used to determine counterintuitive cases in basic electric circuits at the high school level were constructed.
Vibrational spectroscopy in materials
Authors: Thompson Frank
Published: May 2022

An absorption line at 900 nm has been observed in Perspex. Samples of 1 and 2 cm thickness were used and the integrated absorption (line width times peak absorption) of the line was proportionate to the thickness. Facilities for lowering the sample temperature were not available and therefore both measurements were carried out at room temperature. A Red Tide spectrophotometer was used to measure this absorption. According to the Optics Group at National Institute of Standards and Technology, USA, the line can be assigned to the 3rd overtone CH stretch of the methyl and methylene group. The present result was compared with historic data for boron impurities in indium phosphide to demonstrate the versatility of this form of spectroscopy
The sound of the udu
Authors: Vieira L P , Aguiar C E
Published: May 2022

The udu is a traditional Nigerian percussion instrument that can be thought of as a Helmholtz resonator with two apertures. We use a simple two-particle mechanical analogue to study the behaviour of such a resonator and find that the model describes quite well the main features of udu acoustics.
The influence of hypoxia on LET and RBE relationships with implications for ultra-high dose rates and FLASH modelling
Authors: Jones Bleddyn
Published: May 2022

Objective. To investigate relationships between linear energy transfer (LET), fluence rates, changes in radiosensitivity and the oxygen enhancement ratio (OER) in different ion beams and extend these concepts to ultra-high dose rate (UHDR) or FLASH effects. Approach. LET values providing maximum relative biological effect (RBE), designated as LETU, are found for neon, carbon and helium beams. Proton experiments show reduced RBEs with depth in scattered (divergent) beams, but not with scanned beams, suggesting that instantaneous fluence rates (related to track separation distances) can modify RBE, all other RBE-determining factors being equal. Micro-volumetric energy transfer per μm3 (mVET) is defined by LET × fluence. High fluence rates will increase mVET rates, with proportional shifts of LETU to lower values due to more rapid energy transfer. From the relationship between LETU and OER at conventional dose rates, OER reductions in UHDR/FLASH exposures can be estimated and biological effective dose analysis of experimental lung and skin reactions becomes feasible. Main results. The Furusawa et al data show that hypoxic LETU values exceed their oxic counterparts. OER reduces from around 3–1.25 at LETU, although the relative radiosensitivities of the oxic and hypoxic α parameters (the OER(α)) exceed those of the standard OER values. Increased fluence rates are predicted to reduce LETU and OER. Large FLASH single doses will minimise RBE increments due to the β parameter reducing by a factor of 0.5–0.25 consistent with oxygen depletion, causing radioresistance. Similar results will occur for photons. Tissue α/β ratios increase by around 10 in FLASH conditions, agreeing with derived ion-beam dose rate equations. Significance. Increasing dose rates enhance local energy deposition rate per unit volume, probably causing oxygen depletion and radioresistance in pre-existing hypoxic sites during UHDR/FLASH exposures. The modelled equations provide testable hypotheses for further dose rate investigations in photon, proton and ion beams.
Dual-energy CT based mass density and relative stopping power estimation for proton therapy using physics-informed deep learning
Authors: Chang Chih-Wei , Gao Yuan , Wang Tonghe , Lei Yang , Wang Qian , Pan Shaoyan , Sudhyadhom Atchar , Bradley Jeffrey D , Liu Tian , Lin Liyong , Zhou Jun , Yang Xiaofeng
Published: May 2022

Proton therapy requires accurate dose calculation for treatment planning to ensure the conformal doses are precisely delivered to the targets. The conversion of CT numbers to material properties is a significant source of uncertainty for dose calculation. The aim of this study is to develop a physics-informed deep learning (PIDL) framework to derive accurate mass density and relative stopping power maps from dual-energy computed tomography (DECT) images. The PIDL framework allows deep learning (DL) models to be trained with a physics loss function, which includes a physics model to constrain DL models. Five DL models were implemented including a fully connected neural network (FCNN), dual-FCNN (DFCNN), and three variants of residual networks (ResNet): ResNet-v1 (RN-v1), ResNet-v2 (RN-v2), and dual-ResNet-v2 (DRN-v2). An artificial neural network (ANN) and the five DL models trained with and without physics loss were explored to evaluate the PIDL framework. Two empirical DECT models were implemented to compare with the PIDL method. DL training data were from CIRS electron density phantom 062M (Computerized Imaging Reference Systems, Inc., Norfolk, VA). The performance of DL models was tested by CIRS adult male, adult female, and 5-year-old child anthropomorphic phantoms. For density map inference, the physics-informed RN-v2 was 3.3%, 2.9% and 1.9% more accurate than ANN for the adult male, adult female, and child phantoms. The physics-informed DRN-v2 was 0.7%, 0.6%, and 0.8% more accurate than DRN-v2 without physics training for the three phantoms, respectfully. The results indicated that physics-informed training could reduce uncertainty when ANN/DL models without physics training were insufficient to capture data structures or derived significant errors. DL models could also achieve better image noise control compared to the empirical DECT parametric mapping methods. The proposed PIDL framework can potentially improve proton range uncertainty by offering accurate material properties conversion from DECT.
Electric field determination in transient plasmas: in situ & non-invasive methods
Authors: Goldberg Benjamin M , Hoder Tomáš , Brandenburg Ronny
Published: May 2022

One of the primary basic plasma parameters within transient nonequilibrium plasmas is the reduced electric field strength, roughly understood as the ratio of the electrical energy given to the charged species between two collisions. While physical probes have historically been used for electric field measurements, recent advances in high intensity lasers and sensitive detection methods have allowed for non-invasive optical electric field determination in nearly any discharge configuration with time-resolution up to the sub-nanosecond range and sub-millimeter spatial resolution. This topical review serves to highlight several non-invasive methods for in situ electric field strength determination in transient plasmas ranging from high vacuum environments to atmospheric pressure and above. We will discuss the advantages and proper implementation of (i) laser induced fluorescence dip spectroscopy for measurements in low pressure RF discharges, (ii) optical emission spectroscopy based methods for nitrogen, helium or hydrogen containing discharges, (iii) electric field induced coherent Raman scattering, and (iv) electric field induced second harmonic generation. The physical mechanism for each method will be described as well as basic implementation and highlighting recent results.
Revisiting the numerical stability/accuracy conditions of explicit PIC/MCC simulations of low-temperature gas discharges
Authors: Vass M , Palla P , Hartmann P
Published: May 2022

Particle-in-cell (PIC) with Monte Carlo collisions is a fully kinetic, particle based numerical simulation method with increasing popularity in the field of low temperature gas discharge physics. Already in its simplest form (electrostatic, one-dimensional geometry, and explicit time integration), it can properly describe a wide variety of complex, non-local, non-linear phenomena in electrical gas discharges at the microscopic level with high accuracy. However, being a numerical model working with discretized temporal and (partially) spatial coordinates, its stable and accurate operation largely depends on the choice of several model parameters. Starting from four selected base cases of capacitively coupled, radio frequency driven argon discharges, representing low and intermediate pressure and voltage situations, we discuss the effect of the variation of a set of simulation parameters on the plasma density distribution and the electron energy probability function. The simulation parameters include the temporal and spatial resolution, the PIC superparticle weight factor, as well as the electron reflection and the ion-induced electron emission coefficients, characterizing plasma–surface interactions.
Orientation-dependent crossover from retro to specular Andreev reflections in semi-Dirac materials
Authors: Li Hai , Hu Xiang , Ouyang Gang
Published: May 2022

In the framework of Bogoliubov–de Gennes equation, we theoretically study the transport properties in normal-superconducting junctions based on semi-Dirac materials (SDMs). Owing to the intrinsic anisotropy of SDMs, the configuration of Andreev reflection (AR) and the differential conductance are strongly orientation-dependent. For the transport along the linear dispersion direction, the differential conductance exhibits a clear crossover from retro AR to specular AR with increasing the bias-voltage, and the differential conductance oscillates with the interfacial barrier strength without a decaying profile. Conversely, for the transport along the quadratic dispersion direction, the boundary between the retro AR and specular AR becomes ambiguous when the orientation angle increases, and the differential conductance decays with increasing the momentum mismatch or the interfacial barrier strength. We illustrate the pseudo-spin textures to reveal the underling physics behind the anisotropic coherent transport properties. These results enrich the understanding of the superconducting coherent transport in SDMs.
Peroxidation of tetronic 1107 reduces protein chaperone effect
Authors: Ling Michelle X , Nguyen Michelle , McFaul Colin A , Lee Raphael C
Published: May 2022

To enhance the stability of protein therapeutics, pharmaceutical companies have long used various copolymer surfactants as excipients. They act to stabilize proteins by adhering to the hydrophobic surface of the protein preventing denaturation and aggregation. However, some commonly used excipients possess polyoxyalkylene chains that are susceptible to oxidative degradation while in aqueous solution. We postulate that oxidation reactions involving the hydrophobic domains reduce the surfactant’s ability to stabilize the native protein structure. We investigated the effect of UV (λ = 254 nm) radiated poloxamine T1107 (T1107) on its ability to disaggregate DTT denatured hen egg-white lysozyme (HEWL). Peroxidation of UV irradiated T1107 was analyzed using FTIR spectroscopy, the Fe+2to Fe+3ion reduction assay method, and1H NMR. Our results indicate that increased UV irradiation led to structural changes in T1107, specifically the addition of a carbonyl on the formate group. The structural change decreased T1107’s ability to disaggregate HEWL thus supporting our hypothesis. These results indicate that peroxide content is an important parameter to control in polyoxyalkylene-based excipients.
Pellet source density in toroidal plasma configurations based on a 2D Gaussian deposition model
Authors: Zhang Jie , McClenaghan Joseph , Parks Paul , Lao Lang , Wu Wen
Published: May 2022

We develop a two-dimensional (2D) Gaussian deposition model to calculate the initial pellet deposition density immediately after pellet ablation, which is valid before the ∇B-drift of the ablated material significantly shifts its location. A 2D Gaussian particle distribution is assumed in the ablation cloud cross-section. Applying this new model to a typical EAST plasma, and comparing it with the conventional point deposition model, it is found that the new model can resolve the tangential singularity problem encountered by the point deposition model. In addition, the model predicts that the initial pellet deposition density depends strongly on the ablation cloud radius as well as the form of the radial particle distribution in the ablation cloud with tangential injection. The ∇B-drift is then introduced with the drift displacement estimated based on a scaling formula derived from HPI2 simulations. The model can provide a fast evaluation of pellet deposition density compared to the predictive HPI2 code at the expense of acceptable accuracy loss. This model could be a useful tool for physical studies relevant to pellet injection, such as pellet ELM triggering and particle and energy transport.
Influence of traps reversibility on hydrogen permeation and retention in Eurofer97
Authors: Montupet-Leblond F. , Hodille E.A. , Payet M. , Delaporte-Mathurin R. , Bernard E. , Charles Y. , Mougenot J. , Vartanian S. , Grisolia C.
Published: May 2022

The presence of three trapping sites in Eurofer97 and the diffusion and trapping parameters obtained in a previousarticle are confirmed using an additional thermal desorption spectrometry experiment. Using these parameters, permeation cycles are simulated using the diffusion–reaction code mhims in order to study the influence of each trapping site on the permeation dynamics. The concept of traps reversibility is used to qualify this influence. The analysis indicates that the reversibility of the trapping sites is a key parameter in diffusion and permeation dynamics, which must be accounted for to get accurate predictions of hydrogen inventory and permeation.
Energetics of intrinsic point defects and hydrogen in tungsten borides: a first-principles study
Authors: Yang L. , Wirth B.D.
Published: May 2022

To understand the irradiation resistance and hydrogen (H) behavior in tungsten borides (W
x
B
y
) in a burning plasma fusion environment, the energetics of intrinsic point defects and H in six stable ground state W borides, including W2B, WB, WB2, W2B5, WB3 and WB4, have been investigated using first-principles density functional theory calculations. The results show that the formation energies of interstitials and vacancies do not directly depend on the W and B content in W borides. However, the interaction between vacancies of a stoichiometric vacancy (SV) cluster in W
x
B
y
is related to the atomic ratio of B to W (y/x). The vacancies of a minimum-size SV cluster in W
x
B
y
are energetically repulsive for y/x ⩽ 1, while the vacancies energetically bind together for y/x larger than 1. The formation energy of B Frenkel pairs in each W boride is lower than that of W Frenkel pairs. Among the six evaluated W
x
B
y
compositions, WB has the highest and the lowest formation energy of H interstitials and H-vacancy complexes, respectively; however, these two energies in WB2 are in reverse order. The average H binding energies to single vacancies in WB and WB4 are comparable with that in W, while this binding energy in WB3 and WB2 is obviously higher or lower than in W, respectively. The diffusion activation energy of H in W borides is anisotropic. One dimensional (1D) diffusion of H in W2B, as well as 1D/2D diffusion in WB, W2B5, WB3 and WB4 are preferred at relatively low temperatures; however, three-dimensional diffusion of H is predicted in WB2. The diffusion activation energy of H generally increases with B content in W borides due to the increasing local charge deficit caused by strong B–B covalent bonds. This study is useful for evaluating the performance of W borides in a fusion environment.
Test of low-dropout voltage regulators with neutrons and protons
Authors: Abovyan S. , Bianchi B. , Cesaroni M. , Corradi M. , Danielyan V. , Falconi L. , Ferraro R. , Fras M. , Gkountoumis P. , Kortner O. , Kroha H. , Longarini I. , Lunadei R. , Ratto A. , Ricci P. , Richter R. , Rosati S. , Santagata A. , Vari R.
Published: May 2022

The Muon System of the ATLAS experiment at the CERN LHC will be upgraded for the high-luminosity phase of LHC to cope with higher rates and higher radiation levels. Most of the Muon-System on-detector electronics will be replaced. Commercial low-dropout voltage regulators have been considered as a robust, low-noise and economic solution to power distribution. These components should be selected based on their capability to comply to radiation requirements. We tested 7 different types of CMOS LDOs, monitoring online the output voltage of 10 samples of each type. Irradiations were performed in the Radial Channel 1 of the RSV TAPIRO fast neutron reactor at ENEA Casaccia (Rome), to test resistance to non-ionizing energy loss, and at the PIF 200 MeV proton beam at PSI (Villigen), to test for total ionizing dose and single event effects. The experimental setup and the results are presented and discussed in this paper.
Preventing saltwater intrusion in the Coastal of Terengganu, can BRIS soil system help?
Authors: Syazuani M S , Edlic S , Mohd Sofiyan S , Jamilah M S
Published: May 2022

Coastal zone is among the most heavily populated areas across the world. The increasing population and rapid development in this area could lead to the possibility of over pumping groundwater. If the groundwater extracted excessively, the saltwater could intrude into the groundwater system and cause the problem. Thus, to prevent this situation from happen, the coastal wetland which known as the beach ridges interspersed with swales (BRIS) soil system area need to be taken care of, as it can recharge the groundwater. Even though this area has been neglected and undervalued for their ecosystem services (purifying groundwater), there are the potential of this area to prevent the saltwater intrusion from happened. Hence, this paper will highlight the potential of BRIS soil system in preventing the saltwater intrusion.
Community Participation in Gunung Ledang Protected Area: Supporting the Sustainable Development Goal (SDG)
Authors: Bakar Ahmad Naqiyuddin , Ali Alizah , Jangga Rohani , Yaakob Ahmad Nawawi , Salleh Rosnani Mohd , Shukor Mohammad Faried Abdul
Published: May 2022

The 17 Sustainable Development Goals (SDGs), which are an urgent call for action by all countries - developed and developing - in a global partnership. They recognize that ending poverty and other deprivations must go hand-in-hand with strategies that improve health and education, reduce inequality, and spur economic growth - all while tackling climate change and working to preserve our oceans and forests. This paper examines the current practices of community participation and its implications on sustainable development agenda (SDG) in the Gunung Ledang Protected Area, Johor, Malaysia. The research utilizes a combination of primary and secondary data. Interview was employed to gather the primary data, while scholarly works, government documents and archival records are the instruments used for gathering the secondary data. The findings shed light on the implications of community participation on sustainable development agenda (SDG) in the Gunung Ledang Protected Area. The main challenge seems to be the lack of holistic measures in tackling community issues that are in conflict with the objectives of SDG. This main factor stems from a combination of several other issues such as decision-making based on short-term result that are mostly constraint due to budget cut and pandemic effect and the lack of understanding on the real meaning of sustainable agenda. These scenario inadvertently influence development processes and threaten the implementation of SDG.
Tree Species Diversity and Conservation Status of Keniam Forest, Taman Negara, Pahang
Authors: Ruziman Hasya Hannani , Ismail Asmida , Radzun Khairul Adzfa , Ishak Nur Syakireen , Zohari Ahmad Fitri , Kusin Mazlin , Pardi Faezah
Published: May 2022

This study was conducted to quantify the community structure with regards to tree species composition and species diversity of tree communities at Kuala Keniam. Five study plots of 25 m x 20 m each were established randomly covering a total area of 0.25 ha. In each plot, all trees with diameters at breast height of 5 cm and above were tagged, measured and identified. Voucher specimens were then taken for further verification purposes. The floristic composition of Kuala Keniam consists of 244 individuals represented by 142 species, 95 genera and 36 families. Euphorbiaceae was the most speciose family with 20 species and nine genera. Elateriospermum tapos (Euphorbiaceae) was recorded as the most dominant species with 16 trees. Kuala Keniam recorded Shannon-Weiner Diversity index of H’=3.01 and Margalef’s Richness Index with DMG=22.78. Low evenness index of J’ = 0.14 portrayed the unequal distribution of the tree species in the forest. Total tree biomass was estimated at 955.02 t/ha, represented by 815.43 t/ha of above ground biomass and 139.59 t/ha of below ground biomass. Carbon stock was estimated at 448.86 t/ha, contributed by, 383.25 t/ha of above ground carbon and 65.61 t/ha of below ground carbon.
Effects of environmental enrichment on behaviours and faecal glucocorticoid levels in captive sun bear (Helarctus malayanus)
Authors: Abdul-Mawah Siti Sarayati , Chor-Wai Lo , Jasnie Farnidah , Norma-Rashid Y. , Ramli R.
Published: May 2022

Stereotypic behaviour is correlated to stress in wild animals in captivity. When wild animals are exposed to stress repeatedly, they may experience a chronic elevation of glucocorticoids (G.C.s), especially for captive sun bears. This study aimed to investigate the stress in captive sun bears by analysing the cortisol level using Faecal Glucocorticoid Metabolite (FGM) analysis before and after introducing environmental enrichments. 57 samples of faecal captive sun bears were collected from four selected study sites around Malaysia. The behavioural data were collected with an instantaneous sampling method. While for FGM analysis, glucocorticoids were analysed using enzyme immunoassays. As predicted, the stereotypic behaviour increased in pre and post enrichment and decreased during the enrichment period. For FGM analysis, the cortisol level was high in pre-enrichment and low in the enrichment period. In conclusion, the outcome of this study indicated that environmental enrichment might help reduce chronically elevated cortisol concentrations that are generally associated with distress in mammals.
Flower Recognition using Deep Convolutional Neural Networks
Authors: Hanafiah Mastura , Adnan Mohd Azraei , Abdul-Rahman Shuzlina , Mutalib Sofianita , Malik Ariff Md Ab , Shamsuddin Mohd Razif
Published: May 2022

This study investigates the suitable model for flower recognition based on deep Convolutional Neural Networks (CNN) with transfer learning approach. The dataset used in the study is a benchmark dataset from Kaggle. The performance of CNN for plant identification using images of flower are investigated using two popular image classification models: AlexNet and VGG16. Results show that CNN is proven to produce outstanding results for object recognition, but its achievement can still be influenced by the type of images and the number of layers of the CNN architecture. The models produced adequate performance rates, with the VGG16 model achieving the best results. AlexNet and VGG16 models achieved the accuracy of 85.69% and 95.02% respectively. This model can be replicated for flower recognition in other areas, especially in our national heritage, Taman Negara which is among the richest flora ecosystem in the world. The significant feature extraction processes were discussed as well, and this is useful for other types of flowers than the trained dataset.
Development of a small scale BSF rearing system and firsthand experience of the process and its lifecycle
Authors: Khairuddin Dzulaikha , Hassan Siti Nurhaslina Fitriyah , Ghafar Siti Nurfatihah Abdul
Published: May 2022

Black soldier fly larva (BSFL) or also known as Hermetia illucens is a type of insect that has been studied for its potential to bio convert waste into a form of protein and lipid. As the bio-conversion process of food wastage into profitable sources is robust, environmentally friendly without the need for their end-product to be managed, it is a very promising sustainable method that should be explored more. A small-scale experiment was conducted to gain firsthand experience of the BSF rearing process. A portable BSFL production system was designed, developed, and tested in this study. As an addition to the experience, an experiment on the effect of different types of diet on the development of the larvae to prepupae was conducted and several characteristics of the harvested BSFL also was recorded and compared. Results show that the system can support the rearing of BSF and the different diet consumption affected the larvae size and weight. In conclusion, the system could be employed for the small scale BSFL production that not just helping in taking care of the Malaysian food waste but they will also serve as an awareness-raising measure for circular economic solutions.
The Insides of Outdoor Recreation Users towards Recreation Resource Impacts at Taman Negara Pahang, Kuala Tahan
Authors: Bookhari S N , Hashim Z , Khalid M Md. , Jamaludin M A
Published: May 2022

One of the most popular activities in the natural environment is trail walking and hiking. In such necessity, the trail is considered key to the recreational amenity available for the outdoor recreation users with safe accessibility to appreciate the natural and scenic environment. Taman Negara Pahang is the largest park in Malaysia and is located at one of the oldest rainforests in the world. The park has excellent advantages in attracting outdoor recreation users but facing a substantial impact on its recreation resources. The impacts cause undesirable change and degrade the components of recreation resources such as soil, vegetation, wildlife and water resources. This issue threatens its integrity to maintain the benefits of recreation function and reduce the quality of the visitor experience due to the ecological impacts. Thus, it is crucial to assess the extent to which outdoor recreation users perceived recreation resource impacts in Taman Negara Pahang. This research has two objectives: 1) to identify the outdoor recreation users’ perceptions toward recreation resource impacts, and 2) to analyse the outdoor recreation users’ level of acceptance toward recreation resource impacts. There are four entrances, i.e. Kuala Tahan and Sungai Relau in Pahang, Kuala Koh in Kelantan dan Tanjung Mentong in Terengganu. This research chooses explicitly Kuala Tahan because it is the main gateway to the park with the most facilities and amenities for the users. The primary research method is a questionnaire survey on outdoor recreation users after completing their activity. They will be intercepted at Bukit Teresek Trail, Canopy Walkway Trail and Lubok Simpon Trail. The survey was conducted from the 4th until the 9th of September, with 60 respondents involved. The expected outcome of this research is to provide a baseline understanding of the designated trail and effectively facilitate targeted experiential opportunities of a respected environment.
Air Quality Status During Pandemic Covid19 in Urban and Sub-Urban Area in Malaysia
Authors: Mohd Halim N F , Mohd Zahid A Z , Salleh M Z M , Abu Bakar A A
Published: May 2022

This paper discussed the API status in the urban and sub-urban cities in Malaysia before, during and after Movement Control Order (MCO) was implemented in year the 2020. The lockdown implemented worldwide including Malaysia has come as a respite to the environment, especially in air pollutant levels. 2 cities have been chosen in this study that is Kangar (suburban) and Cheras (urban). The Air Pollutant Index (API) data recorded on an hourly basis throughout different series of national lockdown phases was obtained from the Malaysian Air Pollutant Index website. The findings show that the API status quality in sub-urban does not change much compare to the urban area. But it can be seen that the API reduces during MCO implementation in the sub-urban and urban areas. This is because, during the MCO, there are several restrictions on mass movement and gatherings, and the closure of educational institutions, government and private agencies (except for essential services). This MCO restriction reduced the traffic density, industrial activities, and other social activities.
Self-learning Buildings: integrating Artificial Intelligence to create a building that can adapt to future challenges
Authors: Maksoud Aref , Al-Beer Hayder Basel , Mushtaha Emad , Yahia Moohammed Wasim
Published: May 2022

Adaptability is a crucial quality in nature, and Artificial Intelligence (AI) provides leverage for adaptability in Architecture. In this paper, AI is integrated to create Self-learning buildings that can adapt to future challenges. The aim of this study is to make buildings that collect data from their environment through sensors and adapt themselves according to these data. The approach followed in this study is divided into different phases. Phase 1 starts by making an extensive research on the use of AI in Architecture. The data that was gathered from that research in phase 1 was used as guidelines to design the building in phase 2. The design of the building that is in phase 2 follows a parametric approach with the help of machine learning in the form of computational design tools. An algorithm was designed with Rhino modeling & Grasshopper Scripting to generate forms that not only biomimicks the Coral Growth process but also adapt that form to the selected site of the project. Phase 3 shows the selection process for the generated experimental studies. Multiple analyses were made such as sunlight, radiation, and shadow analysis to select the best performing form in terms of energy use. In phase 4, the form is developed to increase the building’s performance. In phase 5, performance analyses are done to prove that resultant form is a climate or environmentally responsive form which have high levels of adaptability. The analysis showed that the radiation exposure of this building is between 200 and 300 kWh/m². The shadow analysis shows the building form provides a shadow length of 8 hours. The analyses proves that the building’s form reduces its energy use thus makes it adaptable. In the last phase, an AI engine system is used to predict the future expansion of the building. Integrating technology in the architecture of future buildings provides adaptable buildings and helps save some of the energy used by buildings and thus build a sustainable planet.
Integrating Augmented Reality in Learning Plants
Authors: Ibrahim Nur Zahirah , Osman Rozianawaty , Ali Azliza Mohd , Hamid Nurzeatul Hamimah Abdul , Nordin Sharifalillah , Shahimi Salwa , Aminuddin Mohd Shariful Hafizal , Razak Fadli Abdul
Published: May 2022

Malaysia’s biodiversity forests are producing numerous species of plants. Books, picture walls, posters, and brochures often use to display these plants’ static images to promote these wilderness treasures. Though the use of these static images fits its purpose, they are less attractive in providing information. ARPlant prototype provides an interactive application that enhances rainforest plants’ information displayed using the mobile platform. We use the Mobile Application Development Lifecycle (MADLC) to design and develop ARPlant. We gauge potential users’ requirements and needs by conducting a survey. We then conduct the user testing using the System Usability Scale (SUS) score. The augmented reality in ARPlant allows users to learn by interactively exploring rainforest plants. Users can view the plants in a 3-dimensional environment.
Extrusion 3D bioprinting of functional self-supporting neural constructs using a photoclickable gelatin bioink
Authors: Yao Yue , Molotnikov Andrey , Parkington Helena C , Meagher Laurence , Forsythe John S
Published: May 2022

Many in vitro models of neural physiology utilize neuronal networks established on two-dimensional substrates. Despite the simplicity of these 2D neuronal networks, substrate stiffness may influence cell morphology, network interactions and how neurons communicate and function. With this perspective, three-dimensional (3D) gel encapsulation is a powerful to recapitulating aspects of in vivo features, yet such an approach is often limited in terms of the level of resolution and feature size relevant for modelling aspects of brain architecture. Here, we report 3D bioplotting of rat primary cortical neural cells using a hydrogel system comprising gelatin norbornene (GelNB) and poly (ethylene glycol) dithiol (PEGdiSH). This bioink benefits from a rapid photo-click chemistry, yielding eight-layer crosshatch neural scaffolds and a filament width of 350 µm. The printability of this system depends on hydrogel concentration, printing temperature, extrusion pressure and speed. These parameters were studied via quantitative comparison between rheology and filament dimensions to determine the optimal printing conditions. Under optimal conditions, cell viability of bioprinted primary cortical neurons at day 1 (68 ± 2%) and at day 7 (68 ± 1%) were comparable to the 2D control group (72 ± 7%). The present study relates material rheology and filament dimensions to generate compliant free-standing neural constructs through bioplotting of low-concentration GelNB-PEGdiSH, which may provide a step forward to study 3D neuronal function and network formation.