bluuebunny/crossref_metadata_2025 huggingface dataset:
Sniffer dogs performance is stable over time in detecting COVID-19 positive samples and agrees with the rapid antigen test in the field
Authors: Pirrone Federica , Piotti Patrizia , Galli Massimo , Gasparri Roberto , La Spina Aldo , Spaggiari Lorenzo , Albertini Mariangela
Published: March 2023

Rapid antigen diagnostic (RAD) tests have been developed for the identification of the SARS-CoV-2 infection. However, they require nasopharyngeal or nasal swab, which is invasive, uncomfortable, and aerosolising. The use of saliva test was also proposed but has not yet been validated. Trained dogs may efficiently smell the presence of SARS-CoV-2 in biological samples of infected people, but further validation is needed both in laboratory and in field. The present study aimed to (1) assess and validate the stability over a specific time period of COVID-19 detection in humans’ armpit sweat by trained dogs thanks to a double-blind laboratory test–retest design, and (2) assess this ability when sniffing people directly. Dogs were not trained to discriminate against other infections. For all dogs (n. 3), the laboratory test on 360 samples yielded 93% sensitivity and 99% specificity, an 88% agreement with the Rt-PCR, and a moderate to strong test–retest correlation. When sniffing people directly (n. 97), dogs’ (n. 5) overall sensitivity (89%) and specificity (95%) were significantly above chance level. An almost perfect agreement with RAD results was found (kappa 0.83, SE 0.05, p = 0.001). Therefore, sniffer dogs met appropriate criteria (e.g., repeatability) and WHO's target product profiles for COVID-19 diagnostics and produced very promising results in laboratory and field settings, respectively. These findings support the idea that biodetection dogs could help reduce the spread of the virus in high-risk environments, including airports, schools, and public transport.
A photocatalytic carbon monoxide-generating effervescent microneedle patch for improved transdermal chemotherapy
Authors: Fu Junzhe , Yu Weijiang , Qian Xuedan , Wang Youxiang , Ji Jian
Published: March 2023

A core–shell MN platform with controllable CO photoproduction was fabricated. Effervescent design enabled efficient CO generation and enhanced drug permeation. The CO-sensitized chemotherapeutic MNs had great curative efficiency for melanoma.
Scale‐wise interaction fusion and knowledge distillation network for aerial scene recognition
Authors: Ning Hailong , Lei Tao , An Mengyuan , Sun Hao , Hu Zhanxuan , Nandi Asoke K.
Published: March 2023

Aerial scene recognition (ASR) has attracted great attention due to its increasingly essential applications. Most of the ASR methods adopt the multi‐scale architecture because both global and local features play great roles in ASR. However, the existing multi‐scale methods neglect the effective interactions among different scales and various spatial locations when fusing global and local features, leading to a limited ability to deal with challenges of large‐scale variation and complex background in aerial scene images. In addition, existing methods may suffer from poor generalisations due to millions of to‐be‐learnt parameters and inconsistent predictions between global and local features. To tackle these problems, this study proposes a scale‐wise interaction fusion and knowledge distillation (SIF‐KD) network for learning robust and discriminative features with scale‐invariance and background‐independent information. The main highlights of this study include two aspects. On the one hand, a global‐local features collaborative learning scheme is devised for extracting scale‐invariance features so as to tackle the large‐scale variation problem in aerial scene images. Specifically, a plug‐and‐play multi‐scale context attention fusion module is proposed for collaboratively fusing the context information between global and local features. On the other hand, a scale‐wise knowledge distillation scheme is proposed to produce more consistent predictions by distilling the predictive distribution between different scales during training. Comprehensive experimental results show the proposed SIF‐KD network achieves the best overall accuracy with 99.68%, 98.74% and 95.47% on the UCM, AID and NWPU‐RESISC45 datasets, respectively, compared with state of the arts.
Transformer vibration and noise monitoring system using internet of things
Authors: Thinh Tran Ngoc Huy , Lam Pham Duc , Tran Huy Q. , Tien Lam Hoang Cat , Thai Pham Huu
Published: March 2023

During continuous operation, transformer problems can occur due to various reasons. In reality, the operating parameters of the transformer have been collected and monitored through the supervisory control and data acquisition (SCADA) systems. However, these systems face many challenges when applied to no‐human substations. Currently, noise signals have been used to detect transformer errors. Abnormal noise recognition and vibration monitoring can recognize the transformer's potential defects and errors. In this study, the authors built an internet of things (IoT) system that allows remote control centres to monitor the condition of transformers through noise and vibration at non‐human substations. The proposed model was equipped with a wireless sensor network node consisting of vibration sensors, audio collectors, Arduino modules, and Lora modules. The authors set up two schemes for the IoT network: one sensor node for a 220‐kV transformer and three sensor nodes for all three phases of the 500‐kV transformer. The data obtained from the sensor node were sent to LoRa Gateway and displayed on the computer through LabVIEW. The study also enabled monitoring of parameters through IoT devices such as Desktops, Laptops, Smartphones from LabVIEW NXG Web VI platform, ThingSpeak, and Amazon S3 storage cloud. In addition, a Model Predictive Control (MPC) algorithm was applied to predict the deterioration of transformer health to maintain the system stability and, hence, prolong the transformer life and operability.
Blind matching algorithm based proxy distribution against internet censorship
Authors: Shi Xin , Guo Yunfei , Hu Hongchao , Wang Yawen , Gao Zhen , Sun Xiaoli
Published: March 2023

Proxy based censorship circumvention technique is treated as one of the most promising approaches to fighting against Internet censorship, and its practical applications like the onion router and Lantern have been widely utilized. However, the proxy distribution, as a basic and core issue, still remains unsolved due to (i) the finiteness and non‐renewable nature of proxy resources, (ii) the heterogeneity of clients and proxies requirements, and (iii) the existence of secondary censorship. In this paper, a win‐win driven proxy distribution mechanism for proxy based censorship circumvention systems is designed by leveraging the blind matching theory. Specifically, a combinational manner is developed to measure the quality of service (QoS) requirements of clients in terms of normalized bandwidth and reliability, and security requirements of proxies in terms of credits and suspicion. Then, by introducing the concept of virtual currency, the proxy distribution issue is formulated as two‐sided combinatorial problems from the perspective of clients and proxies, respectively. To solve the complex NP‐hard combinatorial problems in a win‐win manner without unilateral dominance, a two‐sided many‐to‐many context‐free matching game is constructed, in which the aspiration levels and agreement functions are defined to capture the security and QoS concerns of clients and proxies. Further, a modified notion of pairwise stability is exploited as the solution concept, and a client‐proxy blind matching algorithm with market and information decentralization is proposed to obtain the ε‐pairwise stable solution, where clients and proxies make encounters randomly and update their aspiration levels through a stochastic learning process. Finally, theoretical analysis and numerical results are carried out to validate the properties and performance of the proposed algorithm including stability, complexity, and convergence.
Model‐free adaptive integral sliding mode constrained control with modified prescribed performance
Authors: Huang Xiuwei , Dong Zhiyan , Zhang Feng , Zhang Lihua
Published: March 2023

In this work, a novel model‐free adaptive integral sliding model constrained control strategy with modified prescribed performance is proposed for nonlinear nonaffine systems via full‐form dynamic linearization (FFDL). Firstly, a generalized nonlinear nonaffine system with external disturbance is transformed into an affine system via the FFDL method, which contains a linearly parametric term affine to the control input and preceding output data, and an unknown nonlinear time‐varying term. Then, an adaptive estimation method and a discrete‐time extended state observer (DESO) are used to estimate the pseudo gradient (PG) vector and lumped uncertainties, respectively. Furthermore, an integral sliding mode control scheme containing a modified prescribed performance function and an anti‐windup compensator is designed to keep the output tracking error in the prescribed bound without causing any asymmetric offset error in the steady‐state and to suppress the influence of input saturation. Simulation results demonstrate the superiority of the proposed control scheme.
Multi‐level wireless transmission using resonant tunneling diodes in 300‐GHz band
Authors: Webber Julian , Yamamoto Takumi , Nishigami Naoki , Nishida Yosuke , Fujita Masayuki , Nagatsuma Tadao
Published: March 2023

The authors report on a terahertz band wireless communication experiment employing a resonant tunneling diode receiver (Rx) and uni‐travelling carrier photodiode transmitter. An intermediate‐frequency based transmission facilitates a low‐complexity envelope‐detection type Rx architecture for complex‐modulated signals. Forward error correction recoverable data‐rates using quadrature phase shift keying modulation and 16‐level quadrature amplitude modulation are 60 and 68 Gbit/s, respectively.
A novel self‐adaptive rectifier with wide input range
Authors: Lai Shimiao , Zhang Zihao , Liu Zhijun , Wang Ge , Zhou Yongjie , Zhu Huacheng , Yang Yang
Published: March 2023

A 2.45‐GHz self‐adaptive rectifier based on a two‐way Gysel power divider (PD) with switch networks (SN), an impedance transform network (ITN), a feedback network (FN) and two rectifiers is developed in this paper. The SNs and ITN are controlled by FN according to output voltages. The rectifier is in single‐path mode at a low power level and switches to two‐path mode at a high power level. It has been simulated, fabricated and tested. The original input power range when efficiency is above 50% is from −3 to 11 dBm. After being connected to the PD, the input power range is expanded to −6 to 15 dBm, with a maximum efficiency of 71.1% at 1400 Ω. The proposed design only leverages one type of rectifier. The outputs are symmetric.
Coherence‐adjustable, high‐directional, electrically pumped semiconductor lasers around 650 nm
Authors: Liu Lingjuan , Wang Yufei , Ji Haiyang , Fu Ting , Zheng Wanhua
Published: March 2023

By fabricating patterned electrodes on a dumbbell‐shaped cavity semiconductor laser, the coherence of the laser can be switched by only changing the injection current. The threshold current and the peak power of the laser are 0.75 A and 1.41 W @ 3 A. Under the injection of small and large currents, the measured speckle contrasts are 40.0% @ 0.8 A and 7.0% @ 3 A. And the corresponding horizontal far‐field divergence angles are 4.05° and 8.7°, respectively, showing a high directionality. Such a laser with a wide range of adjustable coherence and a high directionality has a great potential in the field of bioimaging.
Structural analysis attack on finite state machine obfuscated circuits
Authors: Jin Linli , Wang Ke , Li Peng , Xi Wei , Huang Kai
Published: March 2023

In this letter, a structural analysis attack is explored as the first kind of attack to disclose the secret key of the circuit encrypted by the latest obfuscation technique JANUS‐HD. By extracting the finite state machine (FSM) diagram from the circuit and converting structural traces into constraints, the secret key can be deduced by the CP‐SAT solver within a few minutes or even seconds in most cases. Incorrect keys can be further pruned by sequential equivalence checking with several oracles in case more than one key is obtained. The entire attack procedure lasts no longer than a few hours even for an FSM with 4096 states.
Low‐loss and broadband InP mirror‐based out‐of‐plane optical coupler
Authors: Saito Yusuke , Ueda Yuta , Shindo Takahiko , Kurata Yu , Kanazawa Shigeru , Kobayashi Wataru , Ishikawa Mitsuteru
Published: March 2023

The authors developed a mirror‐based out‐of‐plane optical coupler (MOOC) for InP photonic integrated circuits (PICs). The coupler has the coupling loss and alignment tolerance comparable to those of a conventional edge coupler. An asymmetric Mach–Zehnder interferometer (a‐MZI) with the MOOC exhibits little wavelength‐dependent loss (WDL) and a high extinction ratio (ER) of >20 dB over 100‐nm wavelength bandwidth. In addition, the temperature‐independent transmittance spectra were obtained. Finally, the authors fabricated a 4‐ch MOOC array with the pitch of 40 μm, which corresponds to the core pitch of practical multi‐core fibre (MCF).
Transformer‐less unified power flow controller in medium voltage distribution networks
Authors: Abdelrahman Mohamed A. , Wang Sheng , Ming Wenlong , Wu Jianzhong , Jenkins Nick
Published: March 2023

A transformer‐less unified power flow controller (UPFC) is a power electronic device consisting of series and shunt voltage source converters (VSCs) that are not connected to a common DC bus. It can control power flow in medium voltage (MV) distribution networks without the need for interfacing transformers. Hence there is a significant reduction in size and cost compared to a conventional UPFC. This paper investigates the operating range of a transformer‐less UPFC in an MV distribution network and the required power ratings of the series and shunt converters. The results showed that a transformer‐less UPFC is able to provide active power control using partially rated converters. However, its ability to control reactive power is limited by the current ratings of the converters. The analysis was verified using software simulation and hardware experiment.
A novel distributed privacy‐preserving control and data collection method for IoT‐centric microgrids
Authors: Alavi Seyed Amir , Javadipour Mehrnaz , Rahimian Ardavan , Mehran Kamyar
Published: March 2023

The privacy of electricity consumers has become one of the most critical subjects in designing smart meters and their proliferation. In this work, a multilayer architecture has been proposed for anonymous data collection from smart meters, which provides: (1) The anonymity of information for third‐party data consumers; (2) Secure communication to utility provider network for billing purposes; (3) Online control of data sharing for end‐users; (4) Low communication costs based on available Internet of things (IoT) communication protocols. The core elements of this architecture are, first, the digital twin equivalent of the cyber‐physical system and, second, the Tangle distributed ledger network with IOTA cryptocurrency. In this architecture, digital twin models are updated in real‐time by information received from trusted nodes of the Tangle distributed network anonymously. A small‐scale laboratory prototype based on this architecture has been developed using the dSPACE SCALEXIO real‐time simulator and open‐source software tools to prove the feasibility of the proposed solution. The numerical results confirm that after a few seconds of anomaly detection, the microgrid was fully stabilized around its operating point with less than 5% deviation during the transition time.
Improved LSB image steganography with high imperceptibility based on cover‐stego matching
Authors: Al‐Faydi Sama N. M. , Ahmed Sahar Khalid , Al‐Talb Heba N. Y.
Published: March 2023

Information security is an important factor when critical information is transferred. This paper concentrates on finding a method that can hide a message in an image without making any changes to it. The proposed method is novel and based on the Least Significant Bit (LSB) method with a high imperceptibility and capacity. Initially, the secret message bits are compressed using the LZW technique, then the compressed message bits are embedded into the LSB of the edge pixels in the cover image which have the same bit values. As a result, the cover image pixels remain unchanged and the stego image matches the cover image. The addresses of pixels that contain the compressed secret bits are maintained in a file called “location addresses” which the receiver uses to retrieve the compressed secret message. It is possible that the stego image will not be transmitted if it was previously specified by the sender and the receiver. Image quality metrics are applied to several standard images. The obtained PSNR for the stego image is infinity, SSIM and NCC are one, MSE and AD are zero for different embedding capacities in all images, which ensures the stego image's excellent imperceptibility.
Fuzzy optimisation model of an incremental capacity auction formulation with greenhouse gas consideration
Authors: Bhachu Karanveer , Elkasrawy Ayman , Venkatesh Bala
Published: March 2023

An incremental capacity auction (ICA) is a mechanism to procure future generation capacity in a power system. Greenhouse gas (GHG) emissions from generators negatively affect our climate and there is a real need to reduce them. Thus, it is critically important for ICA models to procure future generation capacity that reduces GHG emissions. In this paper, we propose two ICA models incorporating energy‐limited generation (renewables and storage) and a GHG emission constraint. All offers are converted into unforced capacity, negating any effect of energy limitations of generation offers. The first ICA model uses classical optimisation and considers GHG emission limits and maximises social welfare (SW). The second ICA model uses a fuzzy optimisation technique to simultaneously optimise the objectives of SW maximisation and GHG emission minimisation. Both ICA models are tested on two datasets with 10 and 338 capacity supply offers constructed using Ontario data. While both models control GHG emissions as desired, the ICA model with fuzzy optimisation is shown to find a better balance between maximising net SW and minimising GHG emissions, with superior reductions in GHG for minor decreases in SW. Results demonstrate how GHG emission reduction results in increased selection of low carbon generation.
A monocular vision positioning and tracking system based on deep neural network
Authors: Li Huijun , Zhang Yu , Ye Bin , Zhao Hailong
Published: March 2023

In order to locate the mobile robots in three‐dimensional indoor environment, mostly global navigation satellite system‐denied space, a monocular visual space positioning algorithm based on a deep neural network is proposed. First, the authors employ the lightweight YOLOv5 algorithm for target detection, and the LibTorch deep learning framework is used for model deployment to improve the inference speed. Moreover, a multi‐layer perceptron (MLP) neural network with four inputs and two outputs is constructed, which regress the site coordinates of the robot to complete the target localization, and this method is compared with the mathematical model solving algorithm to reflect the accuracy and superiority of positioning algorithm based on the deep neural network. The proposed positioning and tracking system has been successfully applied to international conference on robotics and automation (ICRA) robot competition, and the results show that the positioning mean error estimated by the authors’ method is within 10 cm whilst having good real‐time performance.
A locally modified second-order finite element method for interface problems and its implementation in 2 dimensions
Authors: Frei Stefan , Judakova Gozel , Richter Thomas
Published: March 2023

The locally modified finite element method, which is introduced in Frei and Richter [SIAM J. Numer. Anal.52(2014) 2315–2334], is a simple fitted finite element method that is able to resolve weak discontinuities in interface problems. The method is based on a fixed structured coarse mesh, which is then refined into sub-elements to resolve an interior interface. In this work, we extend the locally modified finite element method in two space dimensions to second order using an isoparametric approach in the interface elements. Thereby we need to take care that the resulting curved edges do not lead to degenerate sub-elements. We prove optimala priorierror estimates in theL2-norm and in a discrete energy norm. Finally, we present numerical examples to substantiate the theoretical findings.
Stabilization of the flat Poiseuille-type flow for viscoelastic polymeric liquid
Authors: Semenko Roman
Published: March 2023

This paper presents a numerical study for the problem of the one-dimensional flow of viscoelastic liquid polymers between two parallel plates. The equations of a rheologically modified Vinogradov–Pokrovskii (mVP) model is used for the formulation of the problem. It is shown that the problem could have multiple steady-state solutions. The evaluation of non-steady solutions was performed to see if the time-dependent solutions got eventually attracted by the steady ones. Also for the case of multiple steady solutions, it was checked which one attracts the non-steady solution if any. The evaluation of time-dependent solutions was used to estimate the stability of equilibrium states. It is revealed that stable steady-state regimes of the problem exist under certain conditions, and also there could be no more than one stable regime for any given set of parameters. The calculations were performed to estimate the values of Reynolds and Weissenberg numbers corresponding to either stable or unstable steady regimes. The result indicates that instability of the steady flow could possibly occur for arbitrary low Reynolds numbers under certain balance of viscous and elastic forces.
A parametric study on control authority and vorticity transport in a compressor airfoil with plasma actuation at low Reynolds number
Authors: Wang Yizhou , Wu Yun , Zong Haohua , Zhang Haideng , Li Yinghong
Published: March 2023

In order to obtain the general criterion of control authority for suppressing flow separation in the compressor airfoil at low Reynolds number by nanosecond pulsed dielectric barrier discharge plasma actuation with different actuation parameters, a parametric study on the actuation power and actuation frequency is performed using a large eddy simulation. A non-dimensional actuation power is proposed to reveal the relationship between the actuation power and the characteristic power of the baseline flow field, in order to provide a reference for obtaining a balance between energy consumption and flow control. With different actuation powers, the mechanism behind the evolution process of vortex structures induced by the plasma actuation is revealed through a decomposition of the vorticity according to the vorticity transport equation and the analysis of the non-dimensional circulation according to the Q criterion. It is found that the evolution shows a relatively consistent tendency and can be divided into three stages corresponding to different disturbance processes induced by Kelvin–Helmholtz instabilities. Finally, a criterion for the effective actuation frequency based on the continuous generation of induced vortex structures is established considering different actuation powers and simplified to specific parameters within the flow field.
Bio-inspired in silico microswimmer: Run and tumble kinematics
Authors: Lee Wanho , Kim Yongsam , Lim Sookkyung
Published: March 2023

We present an in silico microswimmer motivated by peritrichous bacteria, E. coli, which can run and tumble by spinning their flagellar motors counterclockwise (CCW) or clockwise (CW). Runs are the directed movement driven by a flagellar bundle, and tumbles are reorientations of cells caused by some motors' reversals from CCW to CW. In a viscous fluid without obstacles, our simulations reveal that material properties of the hook and the counterrotation of the cell body are important factors for efficient flagellar bundling and that longer hooks in mutant cell models create an instability and disrupt the bundling process, resulting in a limited range of movement. In the presence of a planar wall, we demonstrate that microswimmers can explore environment near surface by making various types of tumble events as they swim close to the surface. In particular, the variation of tumble duration can lead the microswimmer to run in a wide range of direction. However, we find that cells near surface stay close to the surface even after tumbles, which suggests that the tumble motion may not promote cells' escape from the confinement but promote biofilm formation.
Data-driven methods for low-dimensional representation and state identification for the spatiotemporal structure of cavitation flow fields
Authors: Wang Zihao , Zhang Guiyong , Sun Tiezhi , Shi Chongbin , Zhou Bo
Published: March 2023

Computational Fluid Dynamics (CFD) generates high-dimensional spatiotemporal data. The data-driven method approach to extracting physical information from CFD has attracted widespread concern in fluid mechanics. While good results have been obtained for some benchmark problems, the performance on complex flow field problems has not been extensively studied. In this paper, we use a dimensionality reduction approach to preserve the main features of the flow field. Based on this, we perform unsupervised identification of flow field states using a clustering approach that applies data-driven analysis to the spatiotemporal structure of complex three-dimensional unsteady cavitation flows. The result shows that the data-driven method can effectively represent the changes in the spatial structure of the unsteady flow field over time and to visualize changes in the quasi-periodic state of the flow. Furthermore, we demonstrate that the combination of principal component analysis and Toeplitz inverse covariance-based clustering can identify different states of the cavitated flow field with high accuracy. This suggests that the method has great potential for application in complex flow phenomena.
Gas fermentation for microbial sustainable aviation fuel production
Authors: Rodriguez Karen , Pedroso Marcelo , Harris Audrey , Garg Shivani , Hine Damian , Köpke Michael , Schenk Gerhard , Marcellin Esteban
Published: March 2023

The challenge of limiting global warming to below 1.5°C requires all industries to implement new technologies and change practices immediately. The aviation industry contributes 2% of human-induced CO2 emissions and 12% of all transport emissions. Decarbonising the aviation industry, which relies heavily on high-density liquid fuels, has been difficult to achieve. The problems are compounded by the continued reliance on so-called sustainable aviation fuels, which use first-generation agricultural feedstocks, creating a trade-off between biomass for food and feed and its use as a feedstock for energy generation. Decarbonising aviation is also challenging because of problems in developing electric aircraft. Alternative feedstocks already exist that provide a more feasible path towards decelerating climate change. One such alternative is to use gas fermentation to convert greenhouse gases (e.g. from food production and food waste) into fuels using microbial acetogens. Acetogens are anaerobic microorganisms capable of producing alcohols from gaseous CO, CO2 and H2. Australia offers feedstock resources for gas fermentation with abundant H2 and CO2 production in proximity to each other. In this review, we put forward the principles, approaches and opportunities offered by gas fermentation technologies to replace our dependency on fossil fuels for aviation fuel production in Australia.
Cognitive flexibility moderates the association between theory of mind and children’s offer in the Ultimatum Game (La flexibilidad cognitiva modera la relación entre la teoría de la mente y las ofertas de los niños en el Juego del Ultimátum)
Authors: Wang Zhenlin , Wang Lamei , Gao Xiaozi , Zhu Liqi
Published: March 2023

This study examined the cognitive predictors and constraints of children’s strategic offers in the Ultimatum Game. The Ultimatum Game is a one-shot negotiation on the division of a given sum of rewards between two people, where the receiver has the right to punish the proposer by rejecting unfair offers, which results in nil reward for either party. Ninety-four Hong Kong children ranged between three and six years of age (48 girls, M = 4.94, SD = 0.90) participated in an Ultimatum Game, and tasks measuring theory of mind, cognitive flexibility, inhibitory control and verbal ability. Children’s theory of mind, measured with false belief understanding tasks, was positively associated with their Ultimatum Game offers. Regression analysis further demonstrated that cognitive flexibility moderated the association between false belief understanding and children’s offers in the Ultimatum Game. Being able to take the opponent’s perspective prompted children to offer more in the Ultimatum Game, but only when their cognitive flexibility was low.
Alloying, phases and magnetic behaviour of mechanically alloyed FeNiMnCu-based high entropy alloys
Authors: Jahani N. , Reihanian M. , Gheisari Kh.
Published: March 2023

In the present work, FeNiMnCuX (X: Co, Cr, Mo, Ti, W) high entropy alloys are successfully fabricated by mechanical alloying. After 15 h of milling, FeNiMnCu and FeNiMnCuCo alloys form a single FCC structure, while other alloys formed an FCC + BCC mixture structure. All alloys contained homogeneous distributions of Fe and Ni, while Cu was segregated. Alloys FeNiMnCuTi and FeNiMnCuW exhibited homogeneous distributions of Mn, whereas others exhibited Mn-rich islands. Except for the FeNiMnCuTi alloy, all alloys exhibited a soft magnetic behaviour. The saturation magnetisation of the base FeNiMnCu alloy was increased by adding Co and decreased by adding Cr, Mo, Ti, and W.
Liquation-induced loss of ductility in AA7075 aluminium alloy fusion welds
Authors: Pirjamadi Alireza , Alikhani Ali Akbar , Movahedi Mojtaba , Pouranvari Majid
Published: March 2023

This paper investigates the effect of liquation in the partially melted zone (PMZ) on the stress–strain behaviour of the AA7075 arc fusion welds. It is identified that the presence of micro-sized Cu-rich second phases in the initial microstructure of the AA7075 is responsible for constitutional liquation in the PMZ. Although the liquation cracking can be avoided using the proper selection of filler metal, it is demonstrated that the formation of brittle Al2Cu-type intermetallic-containing eutectic structure resulting from non-equilibrium solidification of the liquated grain boundaries can induce a severe loss of ductility in the PMZ. This calls for proper strategies to minimise the grain boundary liquid film thickness to produce a more reliable fusion weld on AA7075 alloy.
Two-Dimensional Gap Solitons in Parity-Time Symmetry Moiré Optical Lattices with Rydberg–Rydberg Interaction
Authors: Li Bin-Bin , Zhao Yuan , Xu Si-Liu , Zhou Qin , Fu Qi-Dong , Ye Fang-Wei , Hua Chun-Bo , Chen Mao-Wei , Hu Heng-Jie , Zhou Qian-Qian , Qiu Zhang-Cai
Published: March 2023

Realizing single light solitons that are stable in high dimensions is a long-standing goal in research of nonlinear optical physics. Here, we address a scheme to generate stable two-dimensional solitons in a cold Rydberg atomic system with a parity-time (PT) symmetric moiré optical lattice. We uncover the formation, properties, and their dynamics of fundamental and two-pole gap solitons as well as vortical ones. The PT symmetry, lattice strength, and the degrees of local and nonlocal nonlinearity are tunable and can be used to control solitons. The stability regions of these solitons are evaluated in two numerical ways: linear-stability analysis and time evolutions with perturbations. Our results provide an insightful understanding of solitons physics in combined versatile platforms of PT-symmetric systems and Rydberg–Rydberg interaction in cold gases.
Did Late Quaternary climate change trigger shifts in mating system in temperate plant species of the Sino-Japanese Floristic Region? A commentary on ‘Genetic and demographic signatures accompanying the evolution of the selfing syndrome in Daphne kiusiana, an evergreen shrub’
Authors: Zhang Xinyi , Comes Hans Peter , Qiu Yingxiong
Published: March 2023

This article comments on:

Eun-Kyeong Han, Ichiro Tamaki, Sang-Hun Oh, Jong-Soo Park, Won-Bum Cho, Dong-Pil Jin, Bo-Yun Kim, Sungyu Yang, Dong Chan Son, Hyeok-Jae Choi, Amarsanaa Gantsetseg, Yuji Isagi, and Jung-Hyun Lee. Genetic and demographic signatures accompanying the evolution of the selfing syndrome in Daphne kiusiana, an evergreen shrub, Annals of Botany, Volume 131, Issue 5, 11 April 2023, Pages 751–767, https://doi.org/10.1093/aob/mcac142
Divergent foraging strategies between populations of sympatric matrilineal killer whales
Authors: Tennessen Jennifer B , Holt Marla M , Wright Brianna M , Hanson M Bradley , Emmons Candice K , Giles Deborah A , Hogan Jeffrey T , Thornton Sheila J , Deecke Volker B
Published: March 2023

In cooperative species, human-induced rapid environmental change may threaten cost–benefit tradeoffs of group behavioral strategies that evolved in past environments. Capacity for behavioral flexibility can increase population viability in novel environments. Whether the partitioning of individual responsibilities within social groups is fixed or flexible across populations is poorly understood, despite its relevance for predicting responses to global change at the population and species levels and designing successful conservation programs. We leveraged bio-logging data from two populations of fish-eating killer whales (Orcinus orca) to quantify patterns of fine-scale foraging movements and their relationships with demography. We reveal striking interpopulation differences in patterns of individual foraging behavior. Females from the endangered Southern Resident (SRKW) population captured less prey and spent less time pursuing prey than SRKW males or Northern Resident (NRKW) females, whereas NRKW females captured more prey than NRKW males. The presence of a calf (≤3 years) reduced the number of prey captured by adult females from both populations, but disproportionately so for SRKW. SRKW adult males with a living mother captured more prey than those whose mother had died, whereas the opposite was true for NRKW adult males. Across populations, males foraged in deeper areas than females, and SRKW captured prey deeper than NRKW. These population-level differences in patterns of individual foraging behavior challenge the existing paradigm that females are the disproportionate foragers in gregarious resident killer whales, and demonstrate considerable variation in the foraging strategies across populations of an apex marine predator experiencing different environmental stressors.
C3. A case of extreme discrepancy between office and ambulatory blood pressure: is it true uncontrolled hypertension?
Authors: Tartila T S , Pujowaskito P , Jannah F D K , Tafriend N A
Published: March 2023

Background

White coat uncontrolled hypertension (WCUH), defined as drug-treated hypertension but with increased blood pressure in the office and normal ambulatory blood pressure, should be assessed in patients with uncontrolled hypertension to prevent overtreatment. We report a case of an extreme WCUH found by ambulatory blood pressure monitoring (ABPM).

Case Summary

A 66-year-old woman was a regular patient in Cardiology Outpatient Clinic, Indonesian Army Central Hospital Gatot Soebroto with uncontrolled hypertension, CAD post-PCI, and insulin-dependent type 2 diabetes mellitus. The patient was overweight (BMI was 24.56 kg/m2) with dyslipidemia and uncontrolled blood glucose. Despite aggressive treatment with ARB, CCB, beta-blockers, diuretic, and clonidine, the patient had persistent hypertension with mean office systolic blood pressure >160/90 mmHg. Echocardiography showed concentric left ventricular hypertrophy. ABPM result found extreme variability of blood pressure with the average 24-hour blood pressure of 93.6/59 mmHg (mean daytime blood pressure was 90/55 mmHg and mean night-time blood pressure was 98.7/65.2 mmHg), intermittent hypotension, and reverse dipper pattern. The blood pressure once dropped to the lowest point of 69/44 mmHg, and the highest was 211/186 mmHg. Based on this result, we classified the patient’s condition as WCUH and adjusted the antihypertensive regiment.

Discussion

This case emphasizes the need to evaluate the presence of WCUH by ABPM in patients with uncontrolled hypertension so antihypertensive drugs could be adjusted accordingly and prevent hypotension.
C4. Acute Limb Ischemia in Covid-19 Patient : A Rare Case Report from Rural to Tertiary Hospital
Authors: Sekaringtyas E , Handari S D , Sembiring Y E
Published: March 2023

Background

Acute limb ischemia is defined as a decrease in blood perfusion to the limbs caused by blockages in peripheral arteries. Coronavirus disease 19 (COVID 19), declared as a pandemic by WHO, affects not only respiratory system but also other organs including cardiovascular system. Patients mainly manifests as venous thromboembolism, while peripheral arteries blockages is less common.

Case Summary

A 53 years old man came to emergency room complaining of pain in his left leg. It was felt since the third day of treatment at the previous hospital, in Tuban, as a covid patient one month ago. The first and third of his left toes were also blackish. There was no history of hypertension, diabetes or smoking. On laboratory result, D-dimer level was elevated by 745 ng/ml (normal range <500 ng/ml), while the others within normal limit. CT Angiography examination showed bilateral legs arterial thrombus which the left side was worse. A thrombectomy was performed, then heparin therapy intravenously was given. During observation at the 4th day after surgery, the sign of necrotic border in the 1st dan 3rd toes were seen clearer and we decided to do mutilation.

Discussion

The pathophysiology of acute limb ischemia in Covid-19 patients is known multifactorial, including endothelial damage, immobilization and hypercoagulable states that have a role in the occurrence of blockages. They may also have an acute thrombosis of non atherosclerotic native arteries. An immediate anticoagulants and vascular interventions are needed to reduce its morbidities.
C12. Atrial Fibrillation post Sinovac-Coronavac Vaccine : A Case Report
Authors: Rismawanti R I , Lalitya W , Rachmanadi M B , Gumilang R A
Published: March 2023

Background

COVID-19 has become a global pandemic. Vaccines are currently used to reduce the morbidity and mortality of the disease. However, research regarding the use of the vaccine is still ongoing. Atrial fibrillation (AF) is one of the rare findings after receiving the COVID-19 vaccine.

Case Summary

A man, 64 years old, presented to the ER with palpitation an hour before admission. He refused to have any angina symptoms. Previously, he got a Sinovac-Coronavac injection one day before. On examination, BP 100/60, HR 114, RR 24, SpO2 99% room air, sub-febrile, other findings within normal limits. ECG showed AF with rapid ventricular response. A routine blood test showed no abnormality, rapid antigen SARS-COV2 negative, and hs Troponin I (hsTn-I) 2.5 ng/L. The patient was diagnosed with atrial fibrillation and given oxygen, amiodarone, aspirin, atorvastatin, and serial ECG post-therapy. ECG post therapy converted into sinus rhythm after 26 hours.

Discussion

Acute SARS-CoV-2 infection increases the susceptibility to new-onset atrial fibrillation (NOAF), but the pathophysiology is not well understood. After receiving the COVID-19 vaccine, the immune system will mimic primary infection. It was unclear why our patients developed NOAF. However, we found an observational zone hs-TnI value and a sub-febrile temperature. Troponin might be elevated in critically ill patients even without myocardial involvement, but this patient is in a good state. However, the correlation between atrial fibrillation and the COVID-19 vaccine is not well understood because of the lack of data.
C23. CARDIAC REHABILITATION AFTER CONGENITAL HEART DISEASE SURGERY
Authors: Suryawan Willy , Ambari Ade Meidian
Published: March 2023

Background

The survival rates of children with congenital heart disease (CHD) have dramatically increased due to the contribution of advance in medical and surgical care. Nonetheless, patients often have decreased exercise capacity and health-related issues that affect their quality of life. Cardiac rehabilitation programs in patients after CHD surgery have shown improvement in peak-VO2 and cardio respiratory fitness . Paradoxically, only a minority of CHD patients receives formal cardiac rehabilitation and are often encouraged towards a sedentary lifestyle as a result of overprotection and uncertainty as to which physical activities and with what intensity should be recommended. We therefore present case report about cardiac rehabilitation after CHD surgery based on current evidence to show the importance and benefit in CHD patient

Case Illustration

A 17 years old female patient came to Rehab clinic after Valve replacement and ASD surgical closure for severe mitral and tricuspid regurgitation, ASD secundum and Cor triatiatum. Her last stay in hospital was prolonged due to several complications. Her appearance was frail and she even was not able to walk. After a thorough examination and 6 minutes walk test, she went phase II rehabilitation. After Cardiac rehabilitation, she got better and her cardio respiratory fitness was improved. Based on her result in 6 minutes walk test and calculation, She was capable to do daily activity life on her own and ready to continue phase III rehabilitation.

Discussion

Patient who have underwent cardiac rehabilitation after congenital heart disease surgery have been presented. Systematic Examination should be performed prior cardiac rehabilitation in order to give an individualized exercise prescription.
C32. Coarctation of the Abdominal Aorta, Disease Beyond the Arch; How do we identify and manage it?: A Case Report
Authors: Pamuna O S , Kurnianingsih N
Published: March 2023

Background

Coarctation of the abdominal aorta (AoA) is a rare case, approximately 0.5-2% of all stenosis aorta. We present an 11-years old boy, diagnosed with coarctation of the abdominal aorta.

Case Description

An 11-years old boy complained about dizziness since 1.5 years ago with hypertension. He underwent hypertension treatment for 1.5 years with a pediatrician but there is no improvement in his blood pressure. His current blood pressure was 150/95 mmHg in upper extremities and 120/80 mmHg in lower extremities with three antihypertensives drugs. We found bruit in the abdomen and decreases pulse in lower extremities. An echocardiogram shows no congenital defect. The first was on suspicion of renal stenosis and underwent ultrasonography of the abdomen but not conclusive. Computed Tomography Angiographic (CTA) showed severe stenosis in the abdominal aorta on level thoracal 11-12. Aortogram shows significant stenosis in the abdominal aorta with a pressure gradient was 47 mmHg. He underwent percutaneous transluminal angioplasty with BMS self-stent implantation. At two month of follow up his blood pressure target was achieved with a minimal dose of oral antihypertensive drugs

Discussion

How to diagnosed coarctation of the abdominal aorta is still challenging and often underdiagnosed. Patients with young age and persistent hypertension should be more careful in diagnosis. A bruit in the abdomen with a weak pulse in the lower extremity raises suspicion of Coarctation of the Abdominal Aorta. The causal treatment is either percutaneous transluminal angioplasty with or without stent implantation or surgery.
C35. Congenital Heart Disease in Neonatal Lupus: a case report
Authors: Pramono A , Abdullah L N
Published: March 2023

Background

Neonatal lupus (NL) is an autoimmune disease acquired in utero after exposure to antibodies produced by the maternal immune system against Ro and La antigens. It is considered as a syndrome since it can comprise manifestations including cardiac, cutaneous, and hematologic abnormalities. In many cases, mothers are clinically asymptomatic and only identified with serologic abnormalities when gestational surveillance reveals foetal bradycardia.

Case Summary

A term baby girl was born by c-section due to prolonged bradycardia, with one-minute APGAR score was five and five-minute APGAR was seven. She was the second baby from gemelli pregnancy of P4A0 mother. On further observation, the respiratory distress deteriorated, with the heart rate around 80-100 beats/minute on electrocardiogram showed total AV block. Laboratory examination showed anaemia, thrombocytopenia, hypoalbuminemia, and elevated C-reactive protein. The chest x-ray revealed pleural effusion, and from echocardiography, there was a small patent ductus arteriosus. ANA panel test showed positive 3+ for anti-Ro (SS-A) and Ro-32 recombinant. During treatment in NICU, this patient received dopamine, dobutamine, invasive mechanical ventilation, and chest tube thoracostomy installation. Later, she was referred to tertiary health care for pacemaker treatment.

Discussion

NL is an uncommon autoimmune disease that is present at birth. Affected infant develop various symptoms and complications, the most significant potential such as congenital heart block. Congenital heart block may manifest in various degrees. In this case, NL presented with a complete heart block which required a pacemaker for treatment.
C50. Obstructive hypertrophic cardiomyopathy in young adult man: a case report
Authors: Sinaga A , Ardini T W , Lubis A C , Hasan H
Published: March 2023

Background

Hypertrophic obstructive cardiomyopathy (obstructive HCM) is an autosomal dominant congenital disease characterized by obstruction of the left ventricular outflow tract with asymmetric septal hypertrophy. Obstructive HCM is predispose to the appearance of malignant ventricular arrhythmias, leading to syncope or sudden death.

Case Description

A 25-years-old male patient came to the hospital with chief complaint intolerance activity and previous syncope, without history of sudden cardiac death in his family member. ECG showed sinus rhytm with left axis deviation and left ventricular hypertrophy. Chest x ray showed cardiomegaly. The echocardiography showed asymmetric septal hypertrophy (septal/posterior wall thickness ratio 1.31), left atrium dilatation (LAVi 94.2 mL/m2), SAM and mild mitral regurgitation, mild aortic regurgitation, hyperdynamic ejection fraction (79%) with lower longitudinal strain values in basal and mid ventricular septal segment, grade I diastolic dysfunction, resting LVOT gradient 19.53 mmHg , provoked LVOT gradient 47.31 mmHg.

Discussion

Non-invasive treatment was given due to LVOT gradient below 50 mmHg. The patient prescribed diltiazem 100mg once daily and recommended clinical evaluation follow-up every year or any worsening of symptoms. The other family member suggested for familial screening echocardiography.