bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular detection and genetic characterization of porcine circovirus 4 (PCV4) in Thailand during 2019–2020
Authors: Sirisereewan Chaitawat , Nguyen Thanh Che , Piewbang Chutchai , Jittimanee Suphattra , Kedkovid Roongtham , Thanawongnuwech Roongroje
Published: March 2023

Porcine circovirus 4 (PCV4) is considered a novel PCV, firstly found in China in 2019 and later discovered in Korea. This present study investigated the prevalence and genetic characteristics of PCV4 from high pig-density areas in Thailand during 2019–2020. From 734 samples, three samples (0.4%) from aborted fetuses and porcine respiratory disease complex (PRDC) cases were found positive for PCV4, two of the PCV4-positive samples were coinfected with both PCV2 and PRRSV, and the other PCV4-positive sample was found coinfected with PCV2. In situ hybridization (ISH) revealed the presence of PCV4 in the bronchial epithelial cells and in lymphocytes and histiocyte-like cells in the lymphoid follicles of the PRDC-affected pig. The complete Thai PCV4 genome had over 98% nucleotide identity with other PCV4 strains and was closely related to the Korean and Chinese PCV4b strains. Importantly, the amino acid residue at position 212 of the Cap gene is recommended for differentiating PCV4a (212L) from PCV4b (212M) based on currently available PCV4 genome sequences. These findings provide important clues for the pathogenesis, epidemiology, and genetic characteristics of PCV4 in Thailand.
Silver-assisted reduction of nitroarenes by an Ag-embedded curcumin/melamine-functionalized magnetic nanocatalyst
Authors: Khaleghi Nima , Forouzandeh-Malati Mohadeseh , Ganjali Fatemeh , Rashvandi Zahra , Zarei-Shokat Simindokht , Taheri-Ledari Reza , Maleki Ali
Published: March 2023

In the current study, we introduce a hybrid magnetic nanocomposite comprised of curcumin (Cur), iron oxide magnetic nanoparticles (Fe3O4 MNPs), melamine linker (Mel), and silver nanoparticles (Ag NPs). Initially, a facile in situ route is administrated for preparing the Fe3O4@Cur/Mel-Ag effectual magnetic catalytic system. In addition, the advanced catalytic performance of the nanocomposite to reduce the nitrobenzene (NB) derivatives as hazardous chemical substances were assessed. Nevertheless, a high reaction yield of 98% has been achieved in short reaction times 10 min. Moreover, the Fe3O4@Cur/Mel-Ag magnetic nanocomposite was conveniently collected by an external magnet and recycled 5 times without a noticeable diminish in catalytic performance. Therefore, the prepared magnetic nanocomposite is a privileged substance for NB derivatives reduction since it achieved notable catalytic activity.
The casein-derived peptide YFYPEL alleviates intestinal epithelial cell dysfunction associated with NEC by regulating the PI3K/AKT signaling pathway
Authors: Chen Wenjuan , Chen Yanjie , Qian Yun , Zhang Jun , Hu Xiaoshan , Yan Xiangyun , Jiang Chengyao , Yao Shuwen , Yu Qinlei , Chen Xiaohui , Han Shuping
Published: March 2023

The effect of peptides in NEC remains poorly understood. Our study showed that YFYPEL reduced inflammation and enhanced migration by regulating the PI3K/AKT pathway. The peptide may thus develop into a novel modality in NEC treatment.
Nonionic oligo(ethylene glycol)-substituted viologen negolytes for aqueous organic redox flow batteries
Authors: Yao Yanxin , Ma Wanzhen , Lei Jiafeng , Wang Zengyue , Lu Yi-Chun , Liu Lei
Published: March 2023

Oligo(ethylene glycol) (OEG)-substituted viologens enable superior cycling stability of the first-electron redox reaction and accessibility of the second-electron energy storage in aqueous organic redox flow batteries (AORFBs).
Advances of metal halide perovskite large-size single crystals in photodetectors: from crystal materials to growth techniques
Authors: Yang Meiyu , Nie Zhiguo , Li Xinyi , Wang Rui , Zhao Yang , Wang Huan
Published: March 2023

The material compositions, preparation strategies and growth techniques of metal halide perovskite single crystals for photodetection application are systematically summarized.
Rhodium-catalyzed double hydroboration of pyridine: the origin of the chemo- and regioselectivities
Authors: Choi Hyoju , Wang Ruibin , Kim Suyeon , Kim Dongwook , Baik Mu-Hyun , Park Sehoon
Published: March 2023

Rhodium catalyzes double hydroboration of pyridine via an unique mechanism involving a Rh-1,2-dihydropyridine adduct to give a mixture of unprecedented tetrahydropyridines bearing a sp3 C–B bond in a specific position.
High bandwidth semipolar (20–21) micro-LED-based white light-emitting diodes utilizing perovskite quantum dots and organic emitters in color-conversion layers for visible light communication and solid-state lighting applications
Authors: Sadhu Annada Sankar , Pai Yi-Hua , Chen Li-Yin , Hsieh Chung-An , Lin Hao-Wu , Kuo Hao-Chung
Published: March 2023

Pictorial representation of high-bandwidth WLEDs by utilizing combinations of perovskite quantum dots (PQDs) and organic materials as color converters under the excitation of a semipolar blue micro-LED.
gem-Bromonitrocyclobutane induced radical cyclization of acrylanilides to construct 2-oxindolesviaphotoredox catalysis
Authors: Guo Yawen , Ma Shanshan , Shi Lin , Liu Lidong , Lei Xingyu , Jiao Peng
Published: March 2023

The nitrocyclobutyl group is introduced into 2-oxindoles under visible light irradiation.
An accuracy improved ratiometric SERS sensor for rhodamine 6G in chili powder using a metal–organic framework support
Authors: Chen Yangjie , Hao Juan , Yin Zhihang , Wang Qinghui , Zhou Youting , Jia Lingpu , Li Huiming , Liao Wenlong , Liu Kunping
Published: March 2023

A novel metal–organic framework (MOF) based ratiometric SERS substrate of Au-MBA@Ag NRs/PSS/MIL-88B-NH2 (AMAPM) was prepared and used for the detection of rhodamine 6G (R6G) in chili powder.
Dynamic event‐triggered leader‐following consensus of nonlinear multi‐agent systems with measurement noises
Authors: Chen Kairui , Yan Chuance , Ren Qijun , Wang Junwei
Published: March 2023

This paper investigates a leader‐following consensus problem for nonlinear multi‐agent systems (MASs) with measurement noises under fixed and Markovian switching topologies, respectively. Noises are considered when each agent measures the states of its neighbours, where intensities of noises are vector functions of relative states. To alleviate the utilization of communication and computation resources, a dynamic event‐triggered consensus protocol is designed, where the coupling strength is restricted in a given interval. By using the stochastic stability theorem, it is shown that leader‐following consensus is achieved under fixed topology, where an estimation of the convergence rate is given. Moreover, the problem is studied under switching topologies subjecting to the Markovian process, which is applicable to practical situations with a time‐varying communication environment. Finally, simulation examples are given to show the correctness of the proposed results.
Beam parameter product optimization of densely arranged multi‐emitter tunnel junction cascaded laser
Authors: Wang Juwen , Xu Chuanwang , Zhang Weiqiao , Qu Hongwei , Zhou Xuyan , Qi Aiyi , Zheng Wanhua
Published: March 2023

A tunnel junction cascaded semiconductor laser with thin waveguide and narrowed spacing between adjacent emitters is designed in this work. It can be concluded theoretically that the spatial size of the spots arrangement in fast axis has a greater impact on the vertical beam parameter product (BPP) of the multi‐emitter cascaded laser than the divergence angle. The measured vertical BPP of the designed narrow emitter spacing (NES) laser has been reduced 42.5%, which implies that the beam quality performance of the laser has been improved and proves the feasibility of this method. Meanwhile, the slope efficiency of the thin waveguide NES laser can reach up to 3.55 W/A under 10 ns duration pulse current.
Unique regolith characteristics of the lunar swirl Reiner Gamma as revealed by imaging polarimetry at large phase angles
Authors: Bhatt M. , Wöhler C. , Rogall J. , Aravind K. , Ganesh S. , Bhardwaj A.
Published: March 2023

Context. Lunar swirls are high-albedo irregular markings that are generally associated with prominent magnetic anomalies. The formation of swirls is still unknown. Near-infrared spacecraft-based imaging suggests reduced space weathering at the locations of swirls. However, the reduced space weathering alone cannot explain the observed spectral properties.

Aims. We provide detailed physical characteristics of the regolith at the Reiner Gamma swirl. For the first time, systematic telescopic observations in a range of phase angles are used to derive the surface roughness, opposition effect strength, and grain size distribution at a spatial resolution of 1 km.

Methods. Imaging polarimetric observations of Reiner Gamma were obtained at the Mount Abu IR Observatory between January and March, 2021. These observations were collected with the two narrow-band continuum filters, GC (green) and RC (red), in a range of phase angles. The georeferenced polarimetric images were used to derive the single-scattering albedo, photometric roughness, and amplitude of the opposition effect by adopting the Hapke reflectance model. We further computed median regolith grain size maps of Reiner Gamma using the derived photometric roughness, albedo, and degree of polarization.

Results. A comparison of the polarization properties of Reiner Gamma swirl with the craters Kepler and Aristarchus suggests grain size variations within the swirl structure. The Hapke modeling of the Reiner Gamma swirl suggests significant changes in the opposition effect strength at the central oval, but only marginal differences in surface roughness from its surroundings. Within the swirl, the median grain size varies significantly in comparison to the background mare grain size of ~45 µm.

Conclusions. Our results confirm the occurrence of surface alteration processes that might have disrupted the regolith microstructure in the Reiner Gamma swirl. These findings are consistent with an external mechanism of swirl formation, by considering interaction between the regolith and cometary gas. Subsequent to its formation, the swirl structure was preserved due to shielding by crustal magnetic field.
Remarks on component factors in K1,r-free graphs
Authors: Dai Guowei , Zhang Zan-Bo , Zhang Xiaoyan
Published: March 2023

An ℱ-factor is a spanning subgraph H such that each connected component of H is isomorphic to some graph in ℱ. We use Pk and K1,r to denote the path of order k and the star of order r + 1, respectively. In particular, H is called a {P2, P3}-factor of G if ℱ = {P2, P3}; H is called a P≥k-factor of G if ℱ = {Pk, Pk+1,…}, where k ≥ 2; H is called an Sn-factor of G if ℱ = {P2, P3, K1,3,…, K1,n}, where n ≥ 2. A graph G is called a ℱ≥k-factor covered graph if there is a ℱ≥k-factor of G including e for any e ∈ E(G). We call a graph G is K1,r-free if G does not contain an induced subgraph isomorphic to K1,r. In this paper, we give a minimum degree condition for the K1,r-free graph with an Sn-factor and the K1,r-free graph with a ℱ≥3-factor, respectively. Further, we obtain sufficient conditions for K1,r-free graphs to be ℱ≥2-factor, ℱ≥3-factor or {P2, P3}-factor covered graphs. In addition, examples show that our results are sharp.
Lumbar Drain Use during Middle Fossa Approaches for Nonneoplastic Pathology of the Skull Base
Authors: Dambrino Robert J. , Wong Gunther W. , Tang Alan R. , Jo Jacob , Yengo-Kahn Aaron M. , Lindquist Nathan R. , Freeman Michael H. , Haynes David S. , Tawfik Kareem O. , Chambless Lola B. , Thompson Reid C. , Morone Peter J.
Published: March 2023

Introduction The middle fossa craniotomy (MFCs) is commonly utilized for spontaneous cerebrospinal fluid (CSF) leaks, encephaloceles, and superior semicircular canal dehiscence (SSCD). This study compares postoperative outcomes of MFCs with and without LD use.

Methods A retrospective cohort study of adults over the age of 18 years presenting for the repair of nonneoplastic CSF leak, encephalocele, or SSCD via MFC from 2009 to 2021 was conducted. The main exposure of interest was the placement of an LD. The primary outcome was the presence of postoperative complications (acute/delayed neurologic deficit, meningitis, intracranial hemorrhage, and stroke). Secondary outcomes included operating room (OR) time, length of stay, recurrence, and need for reoperation.

Results In total, 172 patients were included, 96 of whom received an LD and 76 who did not. Patients not receiving an LD were more likely to receive intraoperative mannitol (n = 24, 31.6% vs. n = 16, 16.7%, p = 0.02). On univariate logistic regression, LD placement did not influence overall postoperative complications (OR: 0.38, 95% confidence interval [CI]: 0.05–2.02, p = 0.28), CSF leak recurrence (OR: 0.75, 95% CI: 0.25–2.29, p = 0.61), or need for reoperation (OR: 1.47, 95% CI: 0.48–4.96, p = 0.51). While OR time was shorter for patients not receiving LD (349 ± 71 vs. 372 ± 85 minutes), this difference was not statistically significant (p = 0.07).

Conclusion No difference in postoperative outcomes was observed in patients who had an intraoperative LD placed compared to those without LD. Operative times were increased in the LD cohort, but this difference was not statistically significant. Given the similar outcomes, we conclude that LD is not necessary to facilitate safe MCF for nonneoplastic skull base pathologies.
Multiportal Retrograde Endoscopy to Enhance Surgical Target Visualization: A Pilot Study
Authors: Konuthula Neeraja , Bly Randall A. , Abuzeid Waleed M. , Humphreys Ian M. , Masco Vanessa V. , Hannaford Blake , Moe Kris S.
Published: March 2023

Objective Current transnasal endoscopic techniques for sinus and skull base surgery use a single endoscope to provide visualization from one perspective curtailing depth perception and compromising visualization of the instrument–target interface. The view can be blocked by instruments, and collisions between instruments often occur. The objective of this study was to investigate the use of multiportal retrograde endoscopy to provide more accurate manipulation of the surgical target.

Design Maxillary antrostomy and frontal sinusotomy were performed on three different cadavers by three different surgeons. A zero-degree rigid endoscope was introduced through the nose for the standard transnasal approach. A flexible endoscope was introduced transorally, directed past the palate superiorly, and then flexed 180 degrees for the retrograde view. Videos of the standard transnasal view from the rigid endoscope and retrograde view from the flexible endoscope were recorded simultaneously.

Results All surgeries were able to be performed with dual-screen viewing of the standard and retrograde view. The surgeons noted that they utilized the retrograde view to adjust the location of ends/tips of their instruments. Four surgeons reviewed the videos and individually agreed that the visualization achieved provided a perspective otherwise not attainable with rigid transnasal endoscopy alone.

Conclusion High-quality visualization of surgical targets such as the frontal or maxillary ostia can be challenging with rigid endoscopes alone. Multiportal retrograde endoscopy provides proof of concept that additional views of a surgical target can be achieved. Additional work is needed to further develop indications, techniques, and generalizability to targets beyond those investigated here.
Endoscopic Repair of Internal Carotid Artery Injury with a Lateral Tongue Muscle Patch Graft: Novel Technique and Literature Review
Authors: Chapurin Nikita , Sharma Rahul K. , Stevens Madelyn N. , Kim Esther , Turner Justin H. , Russell Paul T.
Published: March 2023

Objectives Iatrogenic injury to the internal carotid artery (ICA) is one of the most catastrophic complications of endoscopic sinus and skull base surgery. Previous research has shown that packing with a crushed muscle graft at the injury site can be an effective management technique to control bleeding and prevent the need for ICA sacrifice. Here, we describe a novel and readily available repair donor site—an autologous lateral tongue muscle patch.

Design Three representative cases of a successful repair of ICA injuries using a lateral tongue muscle patch are included in this study. The graft measured approximately 2 × 3 cm and was taken from the lateral intrinsic tongue musculature. We describe the harvest of the graft, its advantages, and the details of operative repair.

Results The lateral tongue provides a large and readily accessible source of muscle within the surgical field that can be quickly harvested during an endoscopic procedure. For the first case, an expanding parasellar ICA pseudoaneurysm was managed with a tongue muscle patch and nasal packing. In the second case, a cavernous ICA injury was sustained during craniopharyngioma resection. Case three involved an ICA injury during endonasal debridement of invasive fungal rhinosinusitis. None of the patients required embolization or neurovascular stenting. Postoperative angiograms and serial computed tomography angiograms showed complete resolution of the pseudoaneurysm, and the patients continued to do well at least 1 year after repair.

Conclusion Lateral tongue muscle graft is an effective and efficient method to manage ICA injuries during endoscopic endonasal surgery. Advantages include the speed of harvest, donor site being readily accessible in the surgical field, and low donor site morbidity. It should be added to the repertoire of possible donor sites for addressing catastrophic sinonasal bleeding.
A Study on the Efficacy of Thrombectomy in Patients with Atherosclerotic and Cardioembolic Basilar Artery Occlusion
Authors: Chen Fulei , Dai Linzhi , Dong Jiangtao , Zhu Licang , Li Yang , Zhang Lei , Zhao Dong
Published: March 2023

Background Studies on basilar artery occlusion are relatively few compared with those of anterior circulation stroke. The aim of the present study was to compare the efficacy of endovascular therapy (EVT) in patients with basilar artery occlusion classified as large artery atherosclerosis (LAA) and cardioembolism (CE), and to analyze the independent risk factors affecting the prognosis of EVT.

Methods A total of 123 people were assigned to the LAA and CE groups (97 to the LAA and 26 to the CE). The primary outcome was a modified Rankin Scale (mRS) score of 2 or lower at 90 days. The primary safety outcome was mortality at 90 days. Secondary safety endpoints included the rates of symptomatic intracranial hemorrhage and reinfarction. Multiple logistic regression was used to screen out independent risk factors for EVT prognosis of the LAA and CE groups.

Results In the analysis, the patients with LAA stroke had better collateral circulation (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology [SIR] score of 2–4; 61.9 vs. 19.2%, p = 0.000), and higher angioplasty rate (32.0 vs. 3.8%, p = 0.002). The proportions of patients with a 90-day mRS score of 0 to 2 and 90-day mortality were not found to be statistically significant between the two groups. Multivariate logistic regression analysis indicated that age, SIR, white blood cell, blood glucose, and modified thrombolysis in cerebral infarction were independent risk factors for the poor prognosis of EVT in the LAA group.

Conclusion Although there were differences in clinical characteristics and imaging features between LAA and CE, there was no evidence of a significant difference in prognosis after EVT. In addition, the National Institutes of Health Stroke Scale score was not among the independent risk factors affecting the prognosis of the LAA group.
L2 learning and religious communities of practice in study
abroad
Authors: Edwards Laura C.
Published: March 2023

The “social turn” in ongoing efforts to understand L2
acquisition in study abroad has brought about valuable additions to the
literature, encouraging researchers to consider notions of identity in study
abroad such as gender, class, nationality, race, and sex. This study focuses on
an under-researched aspect of identity abroad: religiosity, and the benefit of
pre-existing beliefs to find, create, and become a member of religious
communities of practice for personal support – during what can be a difficult
time of adjustment and homesickness – as well as for practice and learning in
the L2. Findings indicate that joining religious communities of practice while
abroad can encourage L2 learning while supporting critical notions of the L2
learner’s identity.
“You just picked it up”
Authors: Zhou Siyang , Baffoe-Djan Jessica Briggs
Published: March 2023

Phrasal verbs are highly common in informal discourse among native English speakers, yet they pose extraordinary
difficulty to second language (L2) English learners. Informed by usage-based theory, this mixed-methods study attempted to
determine the relationship between the amount of out-of-class English exposure in study abroad and the phrasal verb knowledge of
international adult students in the United Kingdom. It also brought foundation program students (i.e., students in a preparation
course for university degrees), a previously under-researched study-abroad population, under the spotlight. One hundred and
eighteen foundation program students at a British university completed a modified Language Contact Profile and a productive
phrasal verb test. Nine students were interviewed to further unravel how they acquired phrasal verbs via informal language
contact. Analyses revealed a significant positive relationship between speaking English with international friends and phrasal
verb knowledge. Hierarchical regression identified that overall English proficiency, spoken input contact, and non-interactive
language contact were significant predictors of phrasal verb scores. This study points to the importance of having meaningful,
emotionally enjoyable, and regular L2 contact to formulaic language competence during study abroad.
Tunable correlation in twisted monolayer–trilayer graphene
Authors: Ding Dongdong , Niu Ruirui , Han Xiangyan , Qu Zhuangzhuang , Wang Zhiyu , Li Zhuoxian , Liu Qianling , Han Chunrui , Lu Jianming
Published: March 2023

Flat-band physics of moiré superlattices, originally discovered in the celebrated twisted bilayer graphene, have recently been intensively explored in multilayer graphene systems that can be further controlled by electric field. In this work, we experimentally find the evidence of correlated insulators at half filling of the electron moiré band of twisted monolayer–trilayer graphene with a twist angle around 1.2°. Van Hove singularity (VHS), manifested as enhanced resistance and zero Hall voltage, is observed to be distinct in conduction and valence flat bands. It also depends on the direction and magnitude of the displacement fields, consistent with the asymmetric crystal structure. While the resistance ridges at VHS can be enhanced by magnetic fields, when they cross commensurate fillings of the moiré superlattice in the conduction band, the enhancement is so strong that signatures of correlated insulator appear, which may further develop into an energy gap depending on the correlation strength. At last, Fermi velocity derived from temperature coefficients of resistivity is compared between conduction and valence bands with different displacement fields. It is found that electronic correlation has a negative dependence on the Fermi velocity, which in turn could be used to quantify the correlation strength.
Early decoding of walking tasks with minimal set of EMG channels
Authors: Barberi Federica , Iberite Francesco , Anselmino Eugenio , Randi Pericle , Sacchetti Rinaldo , Gruppioni Emanuele , Mazzoni Alberto , Micera Silvestro
Published: March 2023

Objective. Powered lower-limb prostheses relying on decoding motor intentions from non-invasive sensors, like electromyographic (EMG) signals, can significantly improve the quality of life of amputee subjects. However, the optimal combination of high decoding performance and minimal set-up burden is yet to be determined. Here we propose an efficient decoding approach obtaining high decoding performance by observing only a fraction of the gait duration with a limited number of recording sites. Approach. Thirteen transfemoral amputee subjects performed five motor tasks while recording EMG signals from four muscles and inertial signals from the prosthesis. A support-vector-machine-based algorithm decoded the gait modality selected by the patient from a finite set. We investigated the trade-off between the robustness of the classifier’s accuracy and the minimization of (i) the duration of the observation window, (ii) the number of EMG recording sites, (iii) the computational load of the procedure, measured the complexity of the algorithm. Main results. When including pre-foot-strike data in the decoding, the combination of three EMG recording sites and the inertial signals led to correct rates above 94% at the 20% of the gait cycle, showing the best trade-off between invasiveness of the setup and accuracy of the classifier. The complexity of the algorithm proved to be significantly higher when applying a polynomial kernel compared to a linear one, while the correct rate of the classifier generally showed no differences between the two approaches. The proposed algorithm led to high performance with a minimal EMG set-up and using only a fraction of the gait duration. Significance. These results pave the way for efficient control of powered lower-limb prostheses with minimal set-up burden and a rapid classification output.
Multiple Attitude Estimation Models based on a Pressure Sensor Array
Authors: Wang Chongyang , Yu Huapeng
Published: March 2023

Autonomous navigation is critical for autonomous underwater vehicle to complete underwater tasks, and attitude is an essential parameter of autonomous navigation. Inspired by the biomimicry studies, three attitude estimation models based on a pressure sensor array are constructed, which are the direct method, the multi-layer perception model and the attitude estimation model based on physical knowledge respectively. The field tests are carried out to verify the effectiveness of the proposed methods, and the advantages and disadvantages of the three methods are compared. It turns out that the attitude estimation model based on physical knowledge achieves the optimal results, and the estimated error of pitch is lower than 1.9133°, and the estimated error of roll is lower than 2.6719°. Further, there is no cumulative attitude error, which complies that the attitude estimation model based on physical knowledge has a high potential for applications in autonomous navigation systems.
Image Measurement Attribute Extraction Method under Large Error Condition
Authors: Li Feng , Du Xuehui , Liu Aodi , Zhang Liu
Published: March 2023

In recent years, the rapid development of image processing based on deep learning has had a wide impact on industrial production and social life. In the field of information security, image content description as a kind of attribute has been used in authentication, access control and other technologies. In addition to describing what is in an image, fine-grained image content properties should also be able to express the relative size and position relationships between objects. Due to the strong fuzziness of the relative scale between objects in the image, it is not suitable for precise definition. This paper proposes a method to extract measurement attributes under large error to describe the relative size of two parts in an image. Based on image classification and object detection, the error range is estimated by statistical method, and a fuzzy set is constructed as the length unit. Then the contradictory critical points of measurement are used to determine the comparable scale range and similar regions. Finally, the measurement attribute of image content is given. Experiments show that the size description obtained by this method accords with people’s subjective feelings, and can effectively extract the fine-grained attributes of the image.
Metamorphic Robustness Testing for DeepL Translation
Authors: Li Zilong , Xiao Lei , Lin Ruijin , Xiao Zhengxinchao
Published: March 2023

Due to the complexity and flexibility of natural languages, such robustness testing involving the ability of machine translation software to handle incorrect or unintended input are extremely challenging, especially if there is no human oracle or reference translation. In this paper, using metamorphic robustness testing methods, we compare the translation of the primitive input with the translation of a subsequent input that has different types of very small changes and may cause large changes in the translation results. The lack of robustness of the DeepL translation is shown by our experiments, these preliminary results show that metamorphic testing has potential in the field of natural language processing.
Feature Pyramid Network Based on Skip Connect for Vehicle Prediction
Authors: Li Peixin , Liu Jiaqi , Yang Lu
Published: March 2023

The trajectory prediction of the target vehicle can improve the perception ability of autonomous driving vehicles in the open world environment and is an essential technology for realizing high-level fully automatic driving. The traditional vehicle trajectory prediction model based on image input is sensitive to the image style of the dataset and has weak generalization ability. The prediction model based on intermediate features can overcome the problem of different dataset styles. However, there are relatively few explorations on building models based on intermediate semantic features. Inspired by the feature pyramid in image processing, this paper proposes an FPSP (Feature Pyramid network based on Skip connect for vehicle Prediction) network. By adding the pyramid feature branch, the original network is improved. The initial coarse information is hierarchically introduced into corresponding abstract high-dimensional features. Experiments on the KITTI dataset prove that FPSP achieves considerable improvement with only a slight increase in time consumption.
Abnormal Behavior Recognition Model of Power Grid Based on Multi-Scale Feature Fusion
Authors: Kong Qingyu , Zhang Yi , Du Zexu , Zhu Chun , Xiao Bin
Published: March 2023

Artificial intelligence technology is applied to power grid transmission and operation status identification to improve the intelligence level of power inspection. However, the existing grid anomalous behavior recognition model has the problem of unsatisfactory accuracy for small target detection. To address this problem, this paper proposes an abnormal behavior recognition model of power grid based on multi-scale feature fusion. First, the texture feature extraction network with a multi-scale mechanism is constructed to obtain object features. Secondly, the graph relation network between target and background is constructed. Finally, the grid abnormal behavior recognition model based on multi-scale feature fusion is constructed. The model proposed in this article is compared with the existing object recognition model in the simulation of the different datasets. In terms of the evaluation accuracy index, the proposed model is 93.27, which is improved by 2.18%.
Deep Reinforcement Learning Based Three-dimensional Path Tracking Control of An Underwater Robot
Authors: Liang Zhenyu , Feng Dongliang , Qu Xingru
Published: March 2023

This paper presents a deep reinforcement learning (DRL)-based three-dimensional path tracking control algorithm of an underwater robot to learn the path-tracking capability by interacting with the environment. To be specific, a hybrid path tracking guidance and controller based on three-dimensional line-of-sight (3D LOS) guidance and twin delayed deep deterministic policy gradient (TD3) algorithm is applied to complete kinematics and dynamics controller design. The reference angle is obtained by LOS algorithm, and TD3 algorithm is used to output the control laws. Aiming at the chattering problem in the output of the reinforcement learning controller, the commands filter and chattering penalty term are designed respectively. The tracking experiment of ten waypoints proves the feasibility of the algorithm proposed in this paper.
Dynamic Parameter Identification for Intelligent PID Control
Authors: Zhen Yan , Hou Mingzhe , Hao Mingrui
Published: March 2023

In this paper, an intelligent PID control structure using dynamic parameter is designed to solve the problem that the parameters of the aircraft model change, which results in controller performance degradation in real physical systems. The system dynamics parameters are identified by the deep neural network, and the parameters of the PID controller are adaptively scheduled based on the parameter identification results, so that the control system has the best matching with the system dynamics and the control performance is the best.
Fuzzy PI Control Active Power Filter Based on Improved Particle Swarm Algorithm
Authors: Yang Shengxin , Sun Xianbo , Zhang Yi
Published: March 2023

Electric vehicle generates a large amount of harmonic when charged, and yet active power filter (APF) can have some reduction in harmonic. Based on APF as the research object, this paper introduces a control system combining particle swarm algorithm (PSO) and fuzzy proportional integral (PI) control for the problems of large overshoot and poor robustness of traditional PI control APF, and further boosts the accuracy of harmonic suppression by improving the weight value of PSO algorithm. MATLAB/SIMULINK simulation experiments show that the harmonic distortion rate of traditional PI control in APF, total harmonic distortion (THD) of can be reduced with traditional PI control decreased by 18.25%, conventional PI control 21.2% decreased by and the control of improved PSO algorithm combined with fuzzy PI control decreased by 22.68%. The simulation results show that the proposed method in this paper can effectively suppress the harmonic fluctuations on the grid side.
Online Weapon-target Assignment based on Distributed Auction Mechanism
Authors: Si JiaShuai , Hao MingRui
Published: March 2023

To solve the problem of online weapon-target assignment (OWTA) in the integration of large-scale search and attack in unknown environment, an OWTA algorithm based on distributed auction mechanism is presented. Aiming at the problem that the traditional combinatorial optimization algorithm needs to set up the global battlefield situation in advance, considering the consumability of resources in the attack process, the integrated search and attack task flow is established. Considering the communication restricted environment, the unmanned aerial vehicles (uavs) are grouped, with centralized architecture within the group and distributed structure between the groups, and the corresponding distributed auction mechanism is constructed to achieve OWTA within the communication range limited. In order to solve the problem that it is difficult to ensure the time consistency of the coordinated attack target, a dubins cooperative path planning based on cooperative particle swarm optimization (CPSO) algorithm is proposed. Particle swarm optimization algorithm is used to adjust the radius of the dubins path of each bomb, so that the uav in the same group can hit the target simultaneously without collision and have the shortest flight range. The simulation results show that the designed distributed auction algorithm takes into account the consumption of attack resources, and quickly redistributes the firepower to the new targets in the dynamic uncertain environment, which ensures the maximization of the execution efficiency of the multi-machine cluster fire allocation task.
Satellite-derived forest canopy greenness shows differential drought vulnerability of secondary forests compared to primary forests in Peru
Authors: Zutta Brian R , Salinas Norma , Cosio Eric G , Tito Richard , Aragón Susan , Nina-Quispe Alex , Roman-Cuesta Rosa Maria
Published: March 2023

Understanding tropical secondary forest canopy greenness and responses to climatic conditions is important for climate change mitigation, particularly in the tropics where secondary forest growth is a substantial carbon sink and a promoted natural climate solution. We here test three hypotheses: (a) forest canopy greenness is higher in younger, secondary forests than in older, primary or mature forests, (b) secondary forests are more vulnerable to climatic pressures and (c) there are significant differences between forest types regarding primary–secondary canopy greenness and their differential responses to drought anomalies. To explore these relationships, we monitored wet and dry seasonal greenness from 2001 to 2020, estimated through the enhanced vegetation index (EVI), of Peruvian tropical dry, montane and lowland secondary forests and compared it to nearby primary forests. We developed predictive models of seasonal EVI using remotely sensed variables, including land surface temperature (LST), evapotranspiration (ET), potential evapotranspiration (PET), ratio of ET and PET (ETn), and the standard precipitation index (SPI). Overall, there was a higher change in annual and seasonal EVI for secondary forests compared to primary forests. However, primary forests maintained relatively stable EVI levels during the wet season despite drought anomalies. When decoupling forest type canopy greenness and drought response, primary forest greenness in dry and lowland ecosystems were temporally more stable. Secondary montane had a lower increase in greenness when drought anomalies held during different seasons. Stepwise multiple linear regression models indicated that LST and ETn, a plant water use index, were the most significant factors to predict greening fluctuations in dry and montane forest types. ET and SPI mostly drove wet season mean EVI across all forest types. Predictors of dry season mean EVI varied, but mostly including water availability. Our results suggest that tropical secondary forests are more productive overall yet more vulnerable to prolonged drought.
Sundman transformation and alternative tangent structures
Authors: Cariñena J F , Martínez Eduardo , Muñoz-Lecanda Miguel C
Published: March 2023

A geometric approach to Sundman transformation defined by basic functions for systems of second-order differential equations is developed and the necessity of a change of the tangent structure by means of the function defining the Sundman transformation is shown. Among other applications of such theory we study the linearisability of a system of second-order differential equations and in particular the simplest case of a second-order differential equation. The theory is illustrated with several examples.
Computational approaches for detecting disease-associated alternative splicing events
Authors: Liu Jiashu , Lin Cui-Xiang , Zhang Xiaoqi , Li Zongxuan , Huang Wenkui , Liu Jin , Guan Yuanfang , Li Hong-Dong
Published: March 2023

Alternative splicing (AS) is a key transcriptional regulation pathway. Recent studies have shown that AS events are associated with the occurrence of complex diseases. Various computational approaches have been developed for the detection of disease-associated AS events. In this review, we first describe the metrics used for quantitative characterization of AS events. Second, we review and discuss the three types of methods for detecting disease-associated splicing events, which are differential splicing analysis, aberrant splicing detection and splicing-related network analysis. Third, to further exploit the genetic mechanism of disease-associated AS events, we describe the methods for detecting genetic variants that potentially regulate splicing. For each type of methods, we conducted experimental comparison to illustrate their performance. Finally, we discuss the limitations of these methods and point out potential ways to address them. We anticipate that this review provides a systematic understanding of computational approaches for the analysis of disease-associated splicing.
Aposematic coloration of Pacific newts (Taricha) provides a qualitatively but not quantitatively honest signal to predators
Authors: Moniz Haley A , Kruleski Sage M , Risbud Amar D , Louden Samuel J H , Hanlon Roger T , Stokes Amber N , Palmer Stephanie E , Feldman Chris R
Published: March 2023

Colourful displays are used by diverse taxa to warn predators of dangerous defences (aposematism). Aposematic coloration is especially widespread among amphibians, which are often protected by harmful toxins. Pacific newts (Taricha) are considered a model of aposematism because when threatened, they arch the head and tail upwards to expose a vivid orange ventrum against a dark dorsum. Given that newts are defended by tetrodotoxin (TTX), a lethal neurotoxin, this signal is assumed to warn predators that an attack would be risky. However, colours have not been quantified in Taricha, and it remains unknown whether coloration provides qualitatively honest (signalling toxic defence) or quantitatively honest (signalling toxin level) warnings. We used two colour quantification methods (spectrometry and hyperspectral imaging) to measure chromatic (hue) and achromatic (brightness) qualities of ventral and dorsal coloration in two newt species (Taricha granulosa and Taricha sierrae). We assessed qualitative honesty using visual models of potential predators (snakes, birds and mammals). Next, we evaluated quantitative honesty by measuring TTX in newts and examining the potential correlation between defence level (amount of TTX) and colorimetrics. We found support for qualitative but not quantitative honesty. Selective pressures and evolutionary constraints might impede the evolution of honest quantitative signalling in this system.
Ornamentation diversified faster than eco-morphology across Nearctic dragonflies
Authors: Hersch Kaitlyn , Moore Michael P
Published: March 2023

Eco-morphology and ornamentation are two phenotypic dimensions along which co-existing species often diverge, yet theory makes contrasting predictions about how these phenotypes diversify relative to each other. Some theory predicts that intense reproductive demands cause more pronounced divergence in ornamentation than in eco-morphology. Other theory predicts that preferences for condition-dependent ornamentation in species encountering divergent ecological conditions will facilitate rapid divergence in eco-morphology but not ornamentation. We evaluated these conflicting predictions in Nearctic Libelluloidea dragonflies by testing if the diversification of a condition-dependent ornament, male wing melanization, was slower and less pronounced between species than the diversification of two key eco-morphological traits, body size and relative wing size. We found that male wing melanization evolved much faster than either body size or relative wing size. Furthermore, in contrast to the patterns for either eco-morphological trait, the best-supported models of diversification in male wing melanization indicate that the majority of divergence arose between the most closely related species. These results reveal that the primary axis of divergence between closely related Libelluloidea dragonflies is ornamentation rather than eco-morphology. Our study therefore suggests that evolutionary responses to disparate reproductive demands may be fundamental to the persistence and co-existence of closely related species.
A single origin for the widely distributed B chromosomes of the gladiator frog Boana albopunctata
Authors: Ferro Juan M , Gatto Kaleb P , Netto Flavia , Resquín Juan J , Costa William , Martí Dardo A , Lourenço Luciana B , Baldo Diego
Published: March 2023

B chromosomes are supernumerary elements that have a wide taxonomic distribution among eukaryotes. Although they are dispensable, they can acquire mechanisms to be overrepresented in the next generation and therefore avoid being eliminated. These elements have been discovered in < 2% of the karyotyped anurans. B chromosomes were described for Argentine and Brazilian populations of Boana albopunctata, a Neotropical tree frog widely distributed in the central region of South America. We assessed the distribution of B chromosomes in this species via cytogenetic studies of 365 specimens from Argentina, Brazil and Paraguay. We found that 101 individuals carried B chromosomes, with striking differences in their frequency of occurrence among localities. Our findings might be related to the evolutionary dynamics of these elements. Microdissection and chromosome painting experiments demonstrated sequence similarity between B chromosomes from localities that are > 1000 km apart, showing the most widely distributed B chromosome system known for anurans. The B chromosome system of B. albopunctata might help to fill the general knowledge gap for these elements in anurans compared with other vertebrates.
Experimental investigation into the effects of Argemone biodiesel/diesel blends on cyclic variations in a multi-cylinder CRDI engine
Authors: Sharma Abhinav , Kumar Prem , Sandhu Sarbjot Singh , Singh Mandeep
Published: March 2023

Internal combustion engines suffer from high cyclic variations that result in higher emissions, lower efficiency, higher fuel consumption and poor drivability. The purpose of this study is to investigate how Argemone mexicana biodiesel (AGB)/diesel blended fuels affect the cyclic variability of combustion parameters such as maximum cylinder pressure (Pmax) and indicated mean effective pressure (IMEP) in a four-cylinder turbocharged intercooled common-rail direct injection engine under various engine loading conditions. The chemical and physical properties of AGB produced from A. mexicana oil were measured and compared according to the ASTM D6751 standards. In various volumetric ratios, AGB and diesel fuel were blended as D100, AB10 (10% AGB + 90% D100), AB20 (20% AGB + 80% D100) and AB30 (30% AGB + 70% D100). The IMEP and Pmax time-series data were collected over 200 consecutive cycles at low, partial and high engine loads at a constant engine speed of 2000 rpm. The coefficients of variation (COV) of combustion parameters (Pmax and IMEP) were measured for different AGB/diesel blends and found to be within acceptable limits. The results show that COVPmax and COVIMEP decrease as the engine load increases. It was observed that at low load, AB10 has the lowest COV (Pmax, IMEP), and at partial and high load, AB20 has the lowest COV (Pmax, IMEP) among all the blends.