bluuebunny/crossref_metadata_2025 huggingface dataset:
Unveiling the Molecular Mechanisms Driving the Capsaicin-Induced Immunomodulatory Effects on PD-L1 Expression in Bladder and Renal Cancer Cell Lines
Authors: Morelli Maria Beatrice , Marinelli Oliviero , Aguzzi Cristina , Zeppa Laura , Nabissi Massimo , Amantini Consuelo , Tomassoni Daniele , Maggi Federica , Santoni Matteo , Santoni Giorgio
Published: May 2022

The blockade of the PD-L1/PD-1 immune checkpoint has promising efficacy in cancer treatment. However, few patients with bladder cancer (BC) or renal cell carcinoma (RCC) respond to this approach. Thus, it is important to implement a strategy to stimulate the immune anti-tumor response. In this scenario, our study evaluated the effects of a low capsaicin (CPS) dose in BC and RCC cell lines. Western blot, qRT-PCR and confocal microscopy were used to assess PD-L1 mRNA and protein expression. Alterations to the cellular oxidative status and changes to the antioxidant NME4 levels, mRNA modulation of cytokines, growth factors, transcriptional factors and oncogene, and the activation of Stat1/Stat3 pathways were examined using Western blot, cytofluorimetry and qRT-PCR profiling assays. In BC, CPS triggers an altered stress oxidative-mediated DNA double-strand break response and increases the PD-L1 expression. On the contrary, in RCC, CPS, by stimulating an efficient DNA damage repair response, thus triggering protein carbonylation, reduces the PD-L1 expression. Overall, our results show that CPS mediates a multi-faceted approach. In modulating PD-L1 expression, there is a rationale for CPS exploitation as a stimulus that increases BC cells’ response to immunotherapy or as an immune adjuvant to improve the efficacy of the conventional therapy in RCC patients.
The AKT1E17K Allele Promotes Breast Cancer in Mice
Authors: Malanga Donatella , Laudanna Carmelo , Mirante Teresa , Colelli Fabiana , Migliozzi Simona , Zoppoli Pietro , Santamaria Gianluca , Roberto Luca , De Marco Carmela , Scarfò Marzia , Montanaro Donatella , Paciello Orlando , Papparella Serenella , Mignogna Chiara , Baldi Alfonso , Viglietto Giuseppe
Published: May 2022

The gain-of-function mutation in the pleckstrin homology domain of AKT1 (AKT1E17K) occurs in lung and breast cancer. Through the use of human cellular models and of a AKT1E17K transgenic Cre-inducible murine strain (R26-AKT1E17K mice), we have demonstrated that AKT1E17K is a bona fide oncogene for lung epithelial cells. However, the role of AKT1E17K in breast cancer remains to be determined. Here, we report the generation and the characterization of a MMTV-CRE; R26-AKT1E17K mouse strain that expresses the mutant AKT1E17K allele in the mammary epithelium. We observed that AKT1E17K stimulates the development of mammary tumors classified as ductal adenocarcinoma of medium–high grade and presented a variety of proliferative alterations classified as adenosis with low-to-high grade dysplasia in the mammary epithelium. A subsequent immunohistochemical characterization suggested they were PR−/HER2−/ER+, basal-like and CK8−/CK10−/CK5+/CK14+. We also observed that, in parallel with an increased proliferation rate, tumors expressing mutant AKT1E17K presented an activation of the GSK3/cyclin D1 pathway in the mammary epithelium and cluster significantly with the human basal-like tumors. In conclusion, we demonstrate AKT1E17K is a bona fide oncogene that can initiate tumors at high efficiency in murine mammary epithelium in vivo.
Oncogenic KRAS-Induced Protein Signature in the Tumor Secretome Identifies Laminin-C2 and Pentraxin-3 as Useful Biomarkers for the Early Diagnosis of Pancreatic Cancer
Authors: Kamal Mohammad Azhar , Siddiqui Imran , Belgiovine Cristina , Barbagallo Marialuisa , Paleari Valentina , Pistillo Daniela , Chiabrando Chiara , Schiarea Silvia , Bottazzi Barbara , Leone Roberto , Avigni Roberta , Migliore Roberta , Spaggiari Paola , Gavazzi Francesca , Capretti Giovanni , Marchesi Federica , Mantovani Alberto , Zerbi Alessandro , Allavena Paola
Published: May 2022

KRAS mutations characterize pancreatic cell transformation from the earliest stages of carcinogenesis, and are present in >95% of pancreatic ductal adenocarcinoma (PDAC) cases. In search of novel biomarkers for the early diagnosis of PDAC, we identified the proteins secreted by the normal human pancreatic cell line (HPDE) recently transformed by inducing the overexpression of the KRASG12V oncogene. We report a proteomic signature of KRAS-induced secreted proteins, which was confirmed in surgical tumor samples from resected PDAC patients. The putative diagnostic performance of three candidates, Laminin-C2 (LAMC2), Tenascin-C (TNC) and Pentraxin-3 (PTX3), was investigated by ELISA quantification in two cohorts of PDAC patients (n = 200) eligible for surgery. Circulating levels of LAMC2, TNC and PTX3 were significantly higher in PDAC patients compared to the healthy individuals (p < 0.0001). The Receiver Operating Characteristics (ROC) curve showed good sensitivity (1) and specificity (0.63 and 0.85) for LAMC2 and PTX3, respectively, but not for TNC, and patients with high levels of LAMC2 had significantly shorter overall survival (p = 0.0007). High levels of LAMC2 and PTX3 were detected at early stages (I–IIB) and in CA19-9-low PDAC patients. In conclusion, pancreatic tumors release LAMC2 and PTX3, which can be quantified in the systemic circulation, and may be useful in selecting patients for further diagnostic imaging.
Relationship between Risk Factors Related to Eating Disorders and Subjective Health and Oral Health
Authors: Jung Eun-Ha , Jun Mi-Kyoung
Published: May 2022

This study examined the factors related to eating disorders (ED) and the relationship between ED and subjective health or subjective oral health in adolescents. The 46,146 adolescents (age 12–18 years) who participated in the Korea Youth Risk Behavior Web-based Survey were selected, including those who had attempted to lose weight within the past 30 days during the survey period. The variables included were eating behavior, BMI, body image subjective health, and subjective oral health. The weight-loss method was divided into two groups (regular exercise, RE, and eating disorder, ED). The data were analyzed using the Rao-Scott χ2 test and logistic regression analysis. The adolescents with an obese body image had a lower risk of ED (OR = 0.75, 95% CI 0.38–1.49) than adolescents with a very thin body image. Adolescents with ED had a higher risk of a poor subjective health assessment (OR = 2.32, 95% CI 1.85–2.91). On the other hand, they had a lower risk of a poor subjective oral health assessment (OR = 0.89, 95% CI 0.71–1.12). ED is closely associated with eating behavior, BMI, body image, oral health behavior, subjective health, and subjective oral health in Korean adolescents.
Evaluating Interactive Language for Children with Autism Spectrum Disorder (ASD) in Different Contexts
Authors: Yang Jinhuan , Gu Wentao , Feng Chen
Published: May 2022

Autism spectrum disorder (ASD) is characterized by impairments in the use of appropriate interactive language (including structural language and pragmatic skills) in social contexts. However, the phenotype and causes of interactive language deficits in children with ASD, in different contexts, are still unclear. In this study, we examined the structural language and pragmatic skills of children with ASD in four contexts: playing, drawing, reading, and free talking. We found that while children with ASD did not exhibit deficits in structural language (e.g., vocabulary and utterance), they clearly exhibit deficits in pragmatic skills. We, also, found that contexts played a key role in the use of interactive language by children with ASD. For example, the reading context had a significant impact on the diversity of vocabulary, while the playing and drawing contexts made an important contribution to the formation of complex utterances. The free talking context, on the other hand, contributed to producing more turns. Furthermore, Spearman’s rank correlation analysis was used to examine the relationships between maternal input and children’s language output. We found that the correlations between structural language and maternal input in children with ASD were not as high as revealed in previous studies, while a, relatively, obvious relationship was found between pragmatic skills and maternal input. Specifically, the total number of turns (TNT) for a child with ASD is related to their mother’s TNT, as are the total number of words (TNW) and number of different words (NDW). These results suggest that (1) assessment of pragmatic skills should be included in the evaluation of children with suspected ASD (2) the influence of context on pragmatic skills needs to be taken into account, when assessing the pragmatic development of children with ASD; and (3) the impact of maternal language on children’s language use is of great importance, for children with ASD.
Lung Recruitment Maneuvers Assessment by Bedside Lung Ultrasound in Pediatric Acute Respiratory Distress Syndrome
Authors: Mor Conejo Mireia , Guitart Pardellans Carmina , Fresán Ruiz Elena , Penela Sánchez Daniel , Cambra Lasaosa Francisco José , Jordan Garcia Iolanda , Balaguer Gargallo Mònica , Pons-Òdena Martí
Published: May 2022

The use of recruitment maneuvers (RMs) is suggested to improve severe oxygenation failure in patients with acute respiratory distress syndrome (ARDS). Lung ultrasound (LUS) is a non-invasive, safe, and easily repeatable tool. It could be used to monitor the lung recruitment process in real-time. This paper aims to evaluate bedside LUS for assessing PEEP-induced pulmonary reaeration during RMs in pediatric patients. A case of a child with severe ARDS due to Haemophilus influenzae infection is presented. Due to his poor clinical, laboratory, and radiological evolution, he was placed on venovenous extracorporeal membrane oxygenation (ECMO). Despite all measures, severe pulmonary collapse prevented proper improvement. Thus, RMs were indicated, and bedside LUS was successfully used for monitoring and assessing lung recruitment. The initial lung evaluation before the maneuver showed a tissue pattern characterized by a severe loss of lung aeration with dynamic air bronchograms and multiple coalescent B-lines. While raising a PEEP of 30 mmH2O, LUS showed the presence of A-lines, which was considered a predictor of reaeration in response to the recruitment maneuver. The LUS pattern could be used to assess modifications in the lung aeration, evaluate the effectiveness of RMs, and prevent lung overdistension.
Effect of Modified Yukmijihwang-Tang on Sleep Quality in the Rat
Authors: Lee SunYoung , Lee Hun-Soo , Ye Minsook , Kim Min-A , Kang Hwajung , Rhie Sung Ja , Lee Mi Young , Jung In Chul , Kang In-Cheol , Shim Insop
Published: May 2022

Many plants have been used in Korean medicine for treating insomnia. However, scientific evidence for their sedative activity has not been fully investigated. Thus, this study was carried out to investigate the sedative effects of the extracts of medicinal plants, including Yukmijihwang-tang and its various modified forms through the 5-HT2c receptor binding assay, and to further confirm its sleep-promoting effects and the underlying neural mechanism in rats utilizing electroencephalography (EEG) analysis. Enzyme-linked immunosorbent assay (ELISA) was used to measure serotonin (5-HT) in the brain. The water extracts of modified Yukmijihwang-tang (YmP) displayed binding affinity to the 5-HT2C receptor (IC50 value of 199.9 µg/mL). YmP (50 mg/kg) administration decreased wake time and increased REM and NREM sleep based on EEG data in rats. Additionally, treatment with YmP significantly increased the 5-HT level in the hypothalamus. In conclusion, the sedative effect of YmP can be attributed to the activation of the central serotonergic systems, as evidenced by the high affinity of binding of the 5-HT2C receptor and increased 5-HT levels in the brain of the rat. This study suggests that YmP can be a new material as a sleep inducer in natural products.
Weak Antilocalization in Polycrystalline SnTe Films Deposited by Magnetron Sputtering
Authors: Li Xiaodong , Yang Yang , Wang Xiaocui , Zhu Peng , Qu Fanming , Wang Zhiwei , Yang Fan
Published: May 2022

Previous works on weak antilocalization (WAL) of SnTe were mostly carried out in MBE-grown films, where the signals of WAL usually coexist with a large parabolic background of classical magnetoresistance. In this article, we present our study on WAL in polycrystalline SnTe films deposited by magnetron sputtering. Due to the polycrystalline nature and the relatively low mobility of the films, the background of conventional magnetoresistance was greatly suppressed, and clean WAL signals, which are well described by the Hikami–Larkin–Nagaoka equation, were obtained at low temperatures. A close analysis of the WAL data shows that the number of transport channels contributing to WAL increases monotonously with decreasing temperatures, reaching N=2.8 at T=1.6 K in one of the devices, which indicates the decoupling of Dirac cones at low temperatures. Meanwhile, as the temperature decreases, the temperature dependence of phase coherence length gradually changes from lϕ∼T−1 to lϕ∼T−0.5, suggesting that the dominant mechanism of phase decoherence switches from electron–phonon scattering to electron–electron scattering. Our results are helpful for understanding the quantum transport properties of SnTe.
Effect of B Addition on Microstructure and Mechanical Properties of High-Strength 13Mn TRIP Steel with Different Annealing Temperatures
Authors: Li Feng , Gao Pengfei , Liu Jie , Zhao Yan , Kang Tao , Zhao Zhengzhi
Published: May 2022

The development of advanced high-strength steel has become the research focus of steel in order to meet low emission requirements. Different annealing temperatures from 600 °C to 900 °C were applied to 1200 MPa Grade 13Mn TRIP steels with (30B steel) or without B (0B steel). The effects of B addition on microstructure and mechanical properties with different annealing temperatures were investigated. Except for M2B in 30B steel, both steels annealed at 600 °C or 700 °C contained only austenite. When annealed at 800 °C or 900 °C, ε-martensite and α′-martensite were observed whereas 30B steel had less of them. 30B steel had higher yield strength (YS) and tensile strength (TS) regardless of the annealing temperature. Total elongation (TE) of 30B steel was smaller when annealed at 600 °C or 700 °C but larger at 800 °C or 900 °C. B addition refined austenite grains, and therefore depressed phase transformation to ε-martensite and α′-martensite during annealing. B addition enhanced YS and TS by refining grains, hindering dislocation movement and promoting phase transformation, but changed the fracture mechanism. The best TS × TE (53.62 GPa%) for 30B steel was reached when annealed at 800 °C. The more sufficiently triggered TRIP effect in high-temperature-annealed 30B steel accounts for its scarcely decreased TS and high TE.
Epidermolysis Bullosa—A Different Genetic Approach in Correlation with Genetic Heterogeneity
Authors: Pânzaru Monica-Cristina , Caba Lavinia , Florea Laura , Braha Elena Emanuela , Gorduza Eusebiu Vlad
Published: May 2022

Epidermolysis bullosa is a heterogeneous group of rare genetic disorders characterized by mucocutaneous fragility and blister formation after minor friction or trauma. There are four major epidermolysis bullosa types based on the ultrastructural level of tissue cleavage: simplex, junctional, dystrophic, and Kindler epidermolysis bullosa. They are caused by mutations in genes that encode the proteins that are part of the hemidesmosomes and focal adhesion complex. Some of these disorders can be associated with extracutaneous manifestations, which are sometimes fatal. They are inherited in an autosomal recessive or autosomal dominant manner. This review is focused on the phenomena of heterogeneity (locus, allelic, mutational, and clinical) in epidermolysis bullosa, and on the correlation genotype–phenotype.
A Narrative Review on Robotic-Assisted Gait Training in Children and Adolescents with Cerebral Palsy: Training Parameters, Choice of Settings, and Perspectives
Authors: Cherni Yosra , Ziane Clara
Published: May 2022

About 70% of children and adolescents with cerebral palsy experience gait impairments which affect their autonomy and well-being. Robotic-assisted gait training using the Lokomat is particularly promising for rehabilitation as it provides a standardized environment favoring the massive repetition of the movement, in which physical demands are low on the therapist and high training loads can be achieved. As no guidelines exist regarding training protocols and Lokomat settings, the goal of this narrative review was to summarize previously published information on the use of RAGT in children and adolescents with cerebral palsy and to provide an opinion on possibilities for improving future research. The thirteen studies reviewed reported both positive and null effects of Lokomat training on gait. Half of the studies combined the Lokomat with other types of training, and only five used a control intervention to assess its benefit. Overall, training was administered 1–5 times per week for 20–60 min, over 1–12 weeks. Although Lokomat settings were not always described, progressively decreasing body weight support and guidance while increasing the treadmill speed appeared to be prioritized. The variety of training protocols and settings used did not allow pooling of the studies to assess the effects of interventions on gait parameters in children and adolescents with cerebral palsy. This narrative review highlights the need for homogenization of interventions so that clear guidelines can emerge and be applied in rehabilitation centers.
VQProtect: Lightweight Visual Quality Protection for Error-Prone Selectively Encrypted Video Streaming
Authors: Gillani Syeda Maria , Asghar Mamoona Naveed , Shifa Amna , Abdullah Saima , Kanwal Nadia , Fleury Martin
Published: May 2022

Mobile multimedia communication requires considerable resources such as bandwidth and efficiency to support Quality-of-Service (QoS) and user Quality-of-Experience (QoE). To increase the available bandwidth, 5G network designers have incorporated Cognitive Radio (CR), which can adjust communication parameters according to the needs of an application. The transmission errors occur in wireless networks, which, without remedial action, will result in degraded video quality. Secure transmission is also a challenge for such channels. Therefore, this paper’s innovative scheme “VQProtect” focuses on the visual quality protection of compressed videos by detecting and correcting channel errors while at the same time maintaining video end-to-end confidentiality so that the content remains unwatchable. For the purpose, a two-round secure process is implemented on selected syntax elements of the compressed H.264/AVC bitstreams. To uphold the visual quality of data affected by channel errors, a computationally efficient Forward Error Correction (FEC) method using Random Linear Block coding (with complexity of O(k(n−1)) is implemented to correct the erroneous data bits, effectively eliminating the need for retransmission. Errors affecting an average of 7–10% of the video data bits were simulated with the Gilbert–Elliot model when experimental results demonstrated that 90% of the resulting channel errors were observed to be recoverable by correctly inferring the values of erroneous bits. The proposed solution’s effectiveness over selectively encrypted and error-prone video has been validated through a range of Video Quality Assessment (VQA) metrics.
Entanglement-Assisted Joint Monostatic-Bistatic Radars
Authors: Djordjevic Ivan B.
Published: May 2022

With the help of entanglement, we can build quantum sensors with sensitivity better than that of classical sensors. In this paper we propose an entanglement assisted (EA) joint monostatic-bistatic quantum radar scheme, which significantly outperforms corresponding conventional radars. The proposed joint monostatic-bistatic quantum radar is composed of two radars, one having both wideband entangled source and EA detector, and the second one with only an EA detector. The optical phase conjugation (OPC) is applied on the transmitter side, while classical coherent detection schemes are applied in both receivers. The joint monostatic-bistatic integrated EA transmitter is proposed suitable for implementation in LiNbO3 technology. The detection probability of the proposed EA joint target detection scheme outperforms significantly corresponding classical, coherent states-based quantum detection, and EA monostatic detection schemes. The proposed EA joint target detection scheme is evaluated by modelling the direct radar return and forward scattering channels as both lossy and noisy Bosonic channels, and assuming that the distribution of entanglement over idler channels is not perfect.
Comparative Study on Students’ Engagement and Academic Outcomes in Live Online Learning at University
Authors: Kobicheva Aleksandra
Published: May 2022

Many studies have assessed students’ engagement with learning and academic outcomes and studied the influence of the engagement level on academic outcomes. Nevertheless, there are few studies that demonstrate the results of live online learning and reveal whether gender or/and education level mediates the relationships between students’ engagement and academic outcomes. A total of 301 under- and postgraduate students from the Humanity Institute of Peter the Great Polytechnic University voluntarily participated in this study. We conducted online surveys to reveal the level of students’ engagement and academic outcomes in the process of live online learning and analyzed the associations between these variables. Results displayed higher levels of engagement and academic outcomes for females, and the difference between the results was significant, particularly for behavioral and emotional engagement (p < 0.001). Significant differences of the measurement factors including behavioral engagement (p < 0.01), cognitive engagement (p < 0.01), and academic outcomes (p < 0.05) were revealed between undergraduate (UG) and postgraduate (PG) students. The findings obtained by using the linear regression analysis technique indicated that engagement scores significantly predict the students’ academic outcomes for both females and males, while UG and PG students demonstrated different results. It was detected that cognitive engagement has a greater effect on academic outcomes for PG students, while behavioral engagement has a greater effect on academic outcomes for UG students.
Is Resilience a Trait or a Result of Parental Involvement? The Results of a Systematic Literature Review
Authors: Kovács Karolina Eszter , Dan Beáta , Hrabéczy Anett , Bacskai Katinka , Pusztai Gabriella
Published: May 2022

Investigating parental involvement has moved to the foreground of research in the past two decades, and research results focusing on family engagement claim its positive impact on children’s academic and non-academic achievement. However, less is known about parental involvement in the case of families with children with special needs. In our systematic review, we collected studies focusing on parental involvement which emphasised the role of resilience. Using the EBSCO Discovery Service, a total of 467 abstracts from 85 databases were screened, of which 28 papers published between 1984 and 2021 met the research criteria. Papers vary according to methodology (interview, focus group conversation, survey, case study, intervention programme and good practice) and disability group (general or specific). Resilience is interpreted in two ways: as a personality trait or a consequence. Four types of papers could be detected which dealt with the target group, specifically papers focusing on children, parents, teachers and professionals, and intervention programmes with multiple focuses. In conclusion, resilience is an element of parental involvement, either as a personality trait or a result. It is indispensable for the successful development of children in terms of academic and non-academic achievement as well. Programmes providing a wider collaboration with actors involved in the development of children seem to be more effective. In general practice, whether the goal is to build upon resilience as a personality trait or target its development as a consequence, strong collaboration between the parents, teachers and professionals concerned in the process can significantly contribute to the child’s psychological, emotional and academic development.
Overcoming Silos: A Sustainable and Innovative Approach to Curriculum Development
Authors: Kirwan Morwenna , Bhatti Alexandra J. , Pacey Verity , Gray Kelly , Dean Catherine M.
Published: May 2022

The COVID-19 pandemic has highlighted the importance of being adaptable and flexible in our teaching practices in higher education. Traditionally, a siloed approach to curriculum development has dominated in higher education institutions. These silos are known to create inefficiencies and, in the context of developing teaching resources, often result in the duplication of curricula, resulting in wasted effort and time, and inconsistent teaching practices. In this short communication, we put forward a sustainable and innovative approach to cross-disciplinary curriculum development, known as the Connected Curriculum for Professionals in Health initiative. This ongoing initiative was launched in 2018 and brought together teaching academics and students to co-design a centralized online repository of high-quality, evidence-based online educational modules that support student learning across disciplines. A mixed-methods evaluation of this initiative found that this is a well-utilized repository of engaging modules (n = 46) that have enhanced learning outcomes for both undergraduate and postgraduate health professional students. The Connected Curriculum for Professionals in Health initiative has wide-ranging applicability, beyond disciplines, and is a sustainable, efficient, and strategic approach to enhance pedagogy and the student experience.
A Computational Framework for Cyber Threats in Medical IoT Systems
Authors: Rathee Geetanjali , Saini Hemraj , Kerrache Chaker Abdelaziz , Herrera-Tapia Jorge
Published: May 2022

Smart social systems are ones where a number of individuals share and interact with each other via various networking devices. There exist a number of benefits to including smart-based systems in networks such as religions, economy, medicine, and other networks. However, the involvement of several cyber threats leads to adverse effects on society in terms of finance, business, liability, economy, psychology etc. The aim of this paper is to present a secure and efficient medical Internet of Things communication mechanism by preventing various cyber threats. The proposed framework uses Artificial Intelligence-based techniques such as Levenberg–Marquardt (LM) and Viterbi algorithms to prevent various social cyber threats during interaction and sharing of messages. The proposed mechanism is simulated and validated with various performance metrics compared with the traditional mechanism.
A Hierarchical Representation Model Based on Longformer and Transformer for Extractive Summarization
Authors: Yang Shihao , Zhang Shaoru , Fang Ming , Yang Fengqin , Liu Shuhua
Published: May 2022

Automatic text summarization is a method used to compress documents while preserving the main idea of the original text, including extractive summarization and abstractive summarization. Extractive text summarization extracts important sentences from the original document to serve as the summary. The document representation method is crucial for the quality of the generated summarization. To effectively represent the document, we propose a hierarchical document representation model Long-Trans-Extr for Extractive Summarization, which uses Longformer as the sentence encoder and Transformer as the document encoder. The advantage of Longformer as sentence encoder is that the model can input long document up to 4096 tokens with adding relative a little calculation. The proposed model Long-Trans-Extr is evaluated on three benchmark datasets: CNN (Cable News Network), DailyMail, and the combined CNN/DailyMail. It achieves 43.78 (Rouge-1) and 39.71 (Rouge-L) on CNN/DailyMail and 33.75 (Rouge-1), 13.11 (Rouge-2), and 30.44 (Rouge-L) on the CNN datasets. They are very competitive results, and furthermore, they show that our model has better performance on long documents, such as the CNN corpus.
Effective Parametrization of Low Order Bézier Motion Primitives for Continuous-Curvature Path-Planning Applications
Authors: Blažič Sašo , Klančar Gregor
Published: May 2022

We propose a new parametrization of motion primitives based on Bézier curves that suits perfectly path-planning applications (and environment exploration) of wheeled mobile robots. The individual motion primitives can simply be calculated taking into account the requirements of path planning and the constraints of a vehicle, given in the form of the starting and ending orientations, velocities, turning rates, and curvatures. The proposed parametrization provides a natural geometric interpretation of the curve. The solution of the problem does not require optimization and is obtained by solving a system of simple polynomial equations. The resulting planar path composed of the primitives is guaranteed to be C2 continuous (the curvature is therefore continuous). The proposed primitives feature low order Bézier (third order polynomial) curves. This not only provides the final path with minimal required turns or unwanted oscillations that typically appear when using higher-order polynomial primitives due to Runge’s phenomenon but also makes the approach extremely computationally efficient. When used in path planning optimizers, the proposed primitives enable better convergence and conditionality of the optimization problem due to a low number of required parameters and a low order of the polynomials. The main contribution of the paper therefore lies in the analytic solution for the third-order Bézier motion primitive under given boundary conditions that guarantee continuous curvature of the composed spline path. The proposed approach is illustrated on some typical scenarios of path planning for wheeled mobile robots.
Model-Based Predictive Control with Graph Theory Approach Applied to Multilevel Back-to-Back Cascaded H-Bridge Converters
Authors: Gaburro Bacheti Gabriel , Sartório Camargo Renner , Silva Amorim Thiago , Yahyaoui Imene , Frizera Encarnação Lucas
Published: May 2022

The multilevel back-to-back cascaded H-bridge converter (CHB-B2B) presents a significantly reduced components per level in comparison to other classical back-to-back multilevel topologies. However, this advantage cannot be fulfilled because of the several internal short circuits presented in the CHB-B2B when a conventional PWM modulation is applied. To solve this issue, a powerful math tool known as graph theory emerges as a solution for defining the converter switching matrix to be used with an appropriate control strategy, such as the model-based predictive control (MPC). Therefore, this research paper proposes a MPC with the graph theory approach applied to CHB-B2B which capable of not only eliminating the short circuit stages, but also exploring all the switching states remaining without losing the converter controllability and power quality. To demonstrate the proposed strategy applicability, the MPC with graph theory approach is tested in four different types of SST configurations, input-parallel output-parallel (IPOP), input-parallel output series (IPOS), input-series output-parallel (ISOP), and input-series output series (ISOS), attending distribution grids with different voltage and power levels. Real-time experimental results obtained in a hardware-in-the-loop (HIL) platform demonstrate the proposed strategy’s effectiveness, such as DC-link voltages regulation, multilevel voltage synthesis, and currents with reduced harmonic content.
Burning Velocities of Pyrotechnic Compositions: Effects of Composition and Granulometry
Authors: Rosères Charles , Courty Léo , Gillard Philippe , Boulnois Christophe
Published: May 2022

Burning velocities of binary and ternary pyrotechnic compositions are measured in gutter. The study focuses on the determination of the joint influence of several parameters: oxidant/reducer ratio, reducer granulometry, and binder content. Measurements are performed following the standard NF T70-541 for burning velocity estimation using an optical acquisition method. Binder content has a linear influence on the burning velocity with a pivot point in slope at supposed stoichiometry. Changing the granulometric class of metallic reducer shows to have different influences before and beyond a 20% diameter reduction.
Improved Deadbeat Predictive Control Based Current Harmonic Suppression Strategy for IPMSM
Authors: Gu Xin , Li Yiyang , Chen Wei , Jin Xuefeng
Published: May 2022

When the interior permanent magnet synchronous motor (IPMSM) is running, there are abundant harmonics in the stator current. In order to achieve the suppression of current harmonics, the current harmonic extraction method and current harmonic controller are studied in this paper. Firstly, a simple and accurate method for extracting current harmonics is proposed by means of multiple synchronous rotating frame transformation (MSRFT). Secondly, an improved deadbeat predictive control (IDPC) based current harmonic controller is designed after analyzing the advantages and disadvantages of traditional current harmonic controllers. Thirdly, IDPC-based current harmonic suppression strategy is proposed by combining the proposed current harmonic extraction method and the proposed current harmonic controller. The proposed strategy can still effectively achieve current harmonic suppression when the motor runs at low speed, medium speed and high speed and the controller parameters are mismatched with the motor parameters. Finally, the feasibility and effectiveness of the proposed strategy are verified by simulation and experiments.
Mechanism of Electron Acceptor Promoting Propionic Acid Transformation in Anaerobic Fermentation
Authors: Jing Hongjing , Li Wenzhe , Wang Ming , Jiao Hao , Sun Yong
Published: May 2022

To improve the conversion efficiency of propionic acid in the post-anaerobic fermentation of biogas slurry, the anaerobic fermentation process using biogas slurry with a high acid content was simulated in an anaerobic reactor at 35 ± 0.5 °C using sodium propionate as the sole substrate. The effects of different electron acceptors (NO3−, SO42− and Fe3+) on propionic acid conversion and the succession of microbial community structures were investigated. The results showed that the experimental group with the electron acceptor NO3− exhibited the best anaerobic fermentation effect, with a maximum propionate removal rate of 94%, which was 36% higher than the control group without an electron acceptor. The maximum methane production rate was 307.6 mL/g COD, an increase of 30% compared with the control group. Thauera, Aquabacterium, Desulfomicrobium, Clostridium_sensu_stricto_1, and other functional microorganisms were all enriched. The dominant functional genes related to redox reactions, such as K03711, K00384, and K03406, were highly enriched in the reactor when Fe3+ and NO3− were added. The study shows that adding an electron acceptor can enhance interactions between microorganisms, achieve efficient propionate conversion, and improve methane production in the system.
Heuristic Intrusion Detection Based on Traffic Flow Statistical Analysis
Authors: Szczepanik Wojciech , Niemiec Marcin
Published: May 2022

As telecommunications are becoming increasingly important for modern systems, ensuring secure data transmission is getting more and more critical. Specialised numerous devices that form smart grids are a potential attack vector and therefore is a challenge for cybersecurity. It requires the continuous development of methods to counteract this risk. This paper presents a heuristic approach to detecting threats in network traffic using statistical analysis of packet flows. The important advantage of this method is ability of intrusion detection also in encrypted transmissions. Flow information is processing by neural networks to detect malicious traffic. The architectures of subsequent versions of the artificial neural networks were generated based on the results obtained by previous iterations by searching the hyperparameter space, resulting in more refined models. Finally, the networks prepared in this way exhibited high performance while maintaining a small size—thereby making them an effective method of attacks detection in network environment to protect smart grids.
An Acoustic Fault Detection and Isolation System for Multirotor UAV
Authors: Bondyra Adam , Kołodziejczak Marek , Kulikowski Radosław , Giernacki Wojciech
Published: May 2022

With the rising popularity of unmanned aerial vehicles (UAVs) and increasing variety of their applications, the task of providing reliable and robust control systems becomes significant. An active fault-tolerant control (FTC) scheme requires an effective fault detection and isolation (FDI) algorithm to provide information about the fault’s occurrence and its location. This work aims to present a prototype of a diagnostic system intended to recognize and identify broken blades of rotary wing UAVs. The solution is based on an analysis of acoustic emission recorded with an onboard microphone array paired with a lightweight yet powerful single-board computer. The standalone hardware of the FDI system was utilized to collect a wide and publicly available dataset of recordings in real-world experiments. The detection algorithm itself is a data-driven approach that makes use of an artificial neural network to classify characteristic features of acoustic signals. Fault signature is based on Mel Frequency Spectrum Coefficients. Furthermore, in the paper an extensive evaluation of the model’s parameters was performed. As a result, a highly accurate fault classifier was developed. The best models allow not only a detection of fault occurrence, but thanks to multichannel data provided with a microphone array, the location of the impaired rotor is reported, as well.
Machine Learning Methods in Damage Prediction of Masonry Development Exposed to the Industrial Environment of Mines
Authors: Chomacki Leszek , Rusek Janusz , Słowik Leszek
Published: May 2022

This paper presents the results of comparative studies on the implementation of machine learning methods in the damage intensity assessment of masonry buildings. The research was performed on existing residential buildings, subjected to negative impacts of the industrial environment induced by coal mining plants during their whole technical life cycle. The research was justified on the grounds of safety of use, as well as potential energy losses and CO2 emissions generated by the inefficient management of building materials resources resulting from poor planning of retrofitting. In this field, the research is in line with the global trends of large-scale retrofitting of existing buildings in European countries due to their thermal insulation parameters and seismic hazard. By combining this with the effects of material degradation throughout the technical lifecycle of buildings, the proposed methods allow for a more efficient approach to maintaining quality management of large groups of buildings, which is part of the sustainable development framework. Due to the multidimensionality of the undertaken problem and the necessity of mathematical representation of uncertainty, it was decided to implement a machine learning approach. The effectiveness of the following methods was analysed: probabilistic neural network, support vector machine, naive Bayes classification and Bayesian belief networks. The complexity of individual methods dictated the order of the adopted research horizon. Within such a research plan, both model parameters were learned, and model structure was extracted from the data, which was applied only to the approach based on Bayesian networks. The results of the conducted analyses were verified by assuming classification accuracy measures. Thus, a method was extracted that allows for the best realisation of the set research objective, which was to create a classification system to assess the intensity of damage to masonry buildings. The paper also presents in detail the characteristics of the described buildings, which were used as input variables, and assesses the effectiveness of the obtained results in terms of utilisation in practice.
D-P-Transformer: A Distilling and Probsparse Self-Attention Rockburst Prediction Method
Authors: Zhang Yu , Li Jitao , Liu Dongqiao , Chen Guangshu , Dou Jiaming
Published: May 2022

Rockburst may cause damage to engineering equipment, disrupt construction progress, and endanger human life. To this day, the occurrence of rockburst remains complex and difficult to predict. This study proposes the D-P-Transformer algorithm to address this issue by improving the embedding structure of the Transformer for specific applications to rockburst data. To reduce the computational requirement, sparse self-attention is adopted to replace self-attention. A distilling operation and multiple layer replicas are simultaneously used to enhance the robustness and speed up the algorithm’s process. Taking all relevant rockburst factors into consideration, multiple experiments are conducted on seven large-scale rockburst datasets with different training ratios to verify the reliability of the proposed D-P-Transformer rockburst prediction algorithm. As compared to the original algorithm, the proposed algorithm shows average reductions of 24.45%, 46.56%, 17.32%, and 48.11% in the mean absolute error (MAE), mean square error (MSE), root mean square error (RMSE), and mean absolute percentage error (MAPE), respectively. The results indicate that the novel D-P-Transformer rockburst prediction algorithm is superior to the Transformer prediction algorithm, and could be used for coal mine rockburst prediction analysis.
Evaluation of the Effect of a Combined Chemical and Thermal Modification of Wood though the Use of Bicine and Tricine
Authors: Jones Dennis , Kržišnik Davor , Hočevar Miha , Zagar Andreja , Humar Miha , Popescu Carmen-Mihaela , Popescu Maria-Cristina , Brischke Christian , Nunes Lina , Curling Simon F. , Ormondroyd Graham , Sandberg Dick
Published: May 2022

The effects of thermal modification of wood have been well established, particularly in terms of reductions in mechanical performance. In recent years, there has been an increase in studies related to the Maillard reaction. More commonly associated with food chemistry, it involves the reaction of amines and reducing sugars during cooking procedures. This study has attempted to combine the use of amines and thermal modification, with subsequent properties investigated for the treatment of spruce (Picea abies (L.) H. Karst) and beech (Fagus sylvatica L.). In this initial study, the combined effects of chemical treatments by tricine and bicine were investigated with thermal modification. Along with some preliminary data on mechanical properties, the modifications which appeared in the wood structure were evaluated by infrared spectroscopy and biological studies according to EN113 and EN117 methodologies. The hierarchal study interpretation of FTIR suggested interactions between the bicine or tricine and the wood, which was partly supported by the analysis of volatile organic compounds (VOC), though other tests were not as conclusive. The potential of the method warrants further consideration, which will be described.
Microbial Communities in Underground Gas Reservoirs Offer Promising Biotechnological Potential
Authors: Buriánková Iva , Molíková Anna , Vítězová Monika , Onderka Vladimír , Vítěz Tomáš , Urbanová Iva , Hanišáková Nikola , Černý Martin , Novák David , Lochman Jan , Zeman Josef , Javůrek Jakub , Machálková Markéta , Dengler Linda , Huber Harald
Published: May 2022

Securing new sources of renewable energy and achieving national self-sufficiency in natural gas have become increasingly important in recent times. The study described in this paper focuses on three geologically diverse underground gas reservoirs (UGS) that are the natural habitat of methane-producing archaea, as well as other microorganisms with which methanogens have various ecological relationships. The objective of this research was to describe the microbial metabolism of methane in these specific anoxic environments during the year. DNA sequencing analyses revealed the presence of different methanogenic communities and their metabolic potential in all sites studied. Hydrogenotrophic Methanobacterium sp. prevailed in Lobodice UGS, members of the hydrogenotrophic order Methanomicrobiales predominated in Dolní Dunajovice UGS and thermophilic hydrogenotrophic members of the Methanothermobacter sp. were prevalent in Tvrdonice UGS. Gas composition and isotope analyses were performed simultaneously. The results suggest that the biotechnological potential of UGS for biomethane production cannot be neglected.
Interaction between Chocolate Polyphenols and Encapsulated Probiotics during In Vitro Digestion and Colonic Fermentation
Authors: Hossain Md Nur , Ranadheera Chaminda Senaka , Fang Zhongxiang , Ajlouni Said
Published: May 2022

This study evaluated the interaction between probiotics and polyphenols in chocolates (45% and 70% cocoa) fortified with encapsulated probiotics. Cocoa powder was used as the main encapsulation component in a Na-alginate plus fructooligosaccharides formulation. Probiotic-chocolates (PCh) were produced by adding 1% encapsulated probiotics to the final mixture. The chocolate samples were subjected to in vitro gastrointestinal digestion and colonic fermentation. The data revealed that the most bioaccessible polyphenols in both formulations of PCh containing 45% and 70% cocoa were released in the gastric digested supernatant. The bioaccessible polyphenols from PCh with 70% cocoa reached 83.22–92.33% and 8.08–15.14% during gastrointestinal digestion and colonic fermentation, respectively. Furthermore, the polyphenols with higher bioaccessibility during colonic fermentation of both PChs developed with the CA1 formulation (cocoa powder 10%, Na-alginate 1% and fructooligosaccharides 2%) were detected in the presence of Streptococcus thermophilus and Lactobacillus sanfranciscensis. The results showed that PCh with specific probiotics favored the bioconversion of a specific polyphenol. For example, chocolate fortified with Lacticaseibacillus casei released larger quantities of epicatechin and procyanidin B1, while Lactiplantibacillus plantarum released more catechin and procyanidin B1 for Lacticaseibacillus rhamnosus LGG. Overall, the study findings concluded that chocolate polyphenols could be utilized by probiotics for their metabolism and modulating the gut, which improved the chocolates’ functionality.