bluuebunny/crossref_metadata_2025 huggingface dataset:
Inadequacy of Vitamin D Does Not Interfere with Body Weight Loss in Women of Reproductive Age after Roux-en-Y Gastric Bypass
Authors: Cruz Sabrina , Matos Andrea Cardoso de , Cruz Suelem Pereira da , Pereira Silvia , Saboya Carlos , Ramalho Andrea
Published: December 2022

Objective: To assess the influence of vitamin D on body weight loss in women who had previously undergone Roux-en-Y gastric bypass (RYGB). Methodology: This is an analytical, longitudinal and retrospective study comprising 40 women of reproductive age who had previously undergone RYGB. To investigate the influence of the serum concentrations of vitamin D on body weight reduction, the variables were analyzed in the pre-operative period (T0), in the first (T1) and in the second postoperative year (T2) and were stratified according to the BMI measured in T1 and T2. In addition, in the pre-operative period, participants were subdivided into groups based on adequacy (G1), deficiency (G2) and insufficiency (G3), according to their serum concentrations of vitamin D. Results: Although weight loss occurred in a substantial way in T1, it continued to decrease in T2 (p = 0.017). The women who reached normal weight within two years of surgery showed the lowest vitamin D concentrations preoperatively when compared to those who were overweight (p = 0.011). Women with preoperative vitamin D deficiency showed increased concentrations in the assessed times (p < 0.001), while the opposite (p = 0.001) occurred in women with adequacy. Conclusion: The study showed that inadequacy of vitamin D does not interfere with weight loss in the two-year-follow-up after RYGB and highlights that vitamin D can present a differentiated response postoperatively, to the detriment of the pre-operative period.
Toxin-like Peptides from the Bacterial Cultures Derived from Gut Microbiome Infected by SARS-CoV-2—New Data for a Possible Role in the Long COVID Pattern
Authors: Brogna Carlo , Cristoni Simone , Brogna Barbara , Bisaccia Domenico Rocco , Marino Giuliano , Viduto Valentina , Montano Luigi , Piscopo Marina
Published: December 2022

It has been 3 years since the beginning of the SARS-CoV-2 outbreak, however it is as yet little known how to care for the acute COVID-19 and long COVID patients. COVID-19 clinical manifestations are of both pulmonary and extra-pulmonary types. Extra-pulmonary ones include extreme tiredness (fatigue), shortness of breath, muscle aches, hyposmia, dysgeusia, and other neurological manifestations. In other autoimmune diseases, such as Parkinson’s disease (PD) or Alzheimer’s Disease (AD), it is well known that role of acetylcholine is crucial in olfactory dysfunction. We have already observed the presence of toxin-like peptides in plasma, urine, and faecal samples from COVID-19 patients, which are very similar to molecules known to alter acetylcholine signaling. After observing the production of these peptides in bacterial cultures, we have performed additional proteomics analyses to better understand their behavior and reported the extended data from our latest in vitro experiment. It seems that the gut microbiome continues to produce toxin-like peptides also after the decrease of RNA SARS-CoV-2 viral load at molecular tests. These toxicological interactions between the gut/human microbiome bacteria and the virus suggest a new scenario in the study of the clinical symptoms in long COVID and also in acute COVID-19 patients. It is discussed that in the bacteriophage similar behavior, the presence of toxins produced by bacteria continuously after viral aggression can be blocked using an appropriate combination of certain drugs.
The Association between Vitamin D and the Components of Male Fertility: A Systematic Review
Authors: Adamczewska Daria , Słowikowska-Hilczer Jolanta , Walczak-Jędrzejowska Renata
Published: December 2022

Objective: Previous systematic reviews of the effects of vitamin D on the components of male fertility have been inconclusive. This article systematically reviews the latest research to examine the relationship between vitamin D, semen quality parameters, and sex hormones production. Methods: MEDLINE, Cochrane, and Web of Science databases were searched using the appropriate keywords. Results: Observational studies indicate significant correlation between vitamin D levels and sperm parameters, with a particular emphasis on sperm motility, and partially suggest a relationship between higher serum testosterone and vitamin D levels. Additionally, interventional studies confirmed that vitamin D supplementation has a positive effect on sperm motility, especially progressive. However, most randomized clinical trials indicate that vitamin D treatment does not have any significant effect on testosterone or other hormone levels. Conclusions: Although our findings add to the discussion regarding the effect of vitamin D on male fertility, there is still no solid evidence to support the use of vitamin D supplementation to improve the outcomes of patients with impaired sperm parameters and hormonal disorders. Additional dedicated clinical studies are needed to clarify the relationship between vitamin D and male fertility, along with its components.
Smoking Affects the Post-Stroke Inflammatory Response of Lipid Mediators in a Gender-Related Manner
Authors: Drozd Arleta , Kotlęga Dariusz , Dmytrów Krzysztof , Szczuko Małgorzata
Published: December 2022

The main goal of our study was to determine the effect of cigarette smoking on selected derivatives of arachidonic acid, linoleic acid, DHA, and EPA, which may be markers of post-stroke inflammation. The eicosanoid profile was compared in both smoking and non-smoking patients, without division and with division into gender. In the group of non-smokers, we observed higher levels of the linolenic acid derivative (LA) 9S HODE (p ≤ 0.05) than in smokers. However, after dividing the results by sex, it turned out that the level of this derivative was higher in non-smoking women compared to smoking women (p ≤ 0.01) and did not differentiate the group of men. Similarly, the level of the arachidonic acid metabolite LTX A4 (p ≤ 0.05) differed only in the group of women. In this group, we also observed a decreased level of 15S HETE in smoking women, but it was statistically insignificant (p ≤ 0.08). On the other hand, the level of this derivative was statistically significantly higher in the group of non-smoking women compared to male non-smokers. The group of men was differentiated by two compounds: TXB2 and NPD1. Male smokers had an almost two-fold elevation of TXB2 (p ≤ 0.01) compared with non-smokers, and in this group, we also observed an increased level of NPD1 compared with male non-smokers. On the other hand, when comparing female non-smokers and male non-smokers, in addition to the difference in 15S HETE levels, we also observed elevated levels of TXB2 in the group of non-smokers. We also analyzed a number of statistically significant correlations between the analyzed groups. Generally, men and women smokers showed a much smaller amount of statistically significant correlations than non-smokers. We believe that this is related to the varying degrees of inflammation associated with acute ischemic stroke and post-stroke response. On the one hand, tobacco smoke inhibits the activity of enzymes responsible for the conversion of fatty acids, but on the other hand, it can cause the failure of the inflammatory system, which is also the body’s defense mechanism. Smoking cigarettes is a factor that increases oxidative stress even before the occurrence of a stroke incident, and at the same time accelerates it and inhibits post-stroke repair mechanisms. This study highlights the effect of smoking on inflammation in both genders mediated by lipid mediators, which makes smoking cessation undeniable.
Piezoelectric Micromachined Ultrasound Transducer Technology: Recent Advances and Applications
Authors: He Yashuo , Wan Haotian , Jiang Xiaoning , Peng Chang
Published: December 2022

The objective of this article is to review the recent advancement in piezoelectric micromachined ultrasound transducer (PMUT) technology and the associated piezoelectric materials, device fabrication and characterization, as well as applications. PMUT has been an active research topic since the late 1990s because of the ultrasound application needs of low cost large 2D arrays, and the promising progresses on piezoelectric thin films, semiconductors, and micro/nano-electromechanical system technology. However, the industrial and medical applications of PMUTs have not been very significant until the recent success of PMUT based fingerprint sensing, which inspired growing interests in PMUT research and development. In this paper, recent advances of piezoelectric materials for PMUTs are reviewed first by analyzing the material properties and their suitability for PMUTs. PMUT structures and the associated micromachining processes are next reviewed with a focus on the complementary metal oxide semiconductor compatibility. PMUT prototypes and their applications over the last decade are then summarized to show the development trend of PMUTs. Finally, the prospective future of PMUTs is discussed as well as the challenges on piezoelectric materials, micro/nanofabrication and device integration.
The Mechanism of CP fandom Behaviors among Chinese Young Adults: A Grounded Theory Study
Authors: Zhou Wanqi , Zhang Yueling , Li Yuner , Sun Qingyang , Yang Zeyang
Published: December 2022

CP fandom behaviors or shipping, a growing popular phenomenon among Chinese young adults, refers to the activities of fans who take great satisfaction from the romantic relationships and interactions of their preferred pairings of idols or virtual characters. CP fans are regarded as a special group of fans with unique identities and interaction styles. This grounded theory study was conducted to explore the mechanism of CP fandom behaviors. Semi-structured in-depth interviews were conducted with thirty-one Chinese CP fans (twenty-eight females and three males). The antecedents, development, behavioral patterns, and consequences of shipping were identified in a comprehensive model. The reasons for CP fandom behaviors include individual factors (e.g., psychological projection, compensation, and social needs) and external factors (e.g., pop culture and internet environment). The consequences include positive emotional experiences, changed love values, and improved social interaction. CP fandom behaviors can be different in terms of the fans’ degrees of engagement, and the development of shipping can be divided into three stages: exploratory stage, formation and stability stage, and rupture stage. This study contributes to the literature of CP fandom behaviors among young adults in China and proposes the directions of future studies on such topics.
Research on the Impact of Intercustomer Social Support on Customer Engagement Behaviors in Virtual Brand Communities
Authors: Li Xuexin , Yang Congcong , Wang Shulin
Published: December 2022

Customer engagement behavior is a key factor in promoting the sustainable growth of virtual brand communities. Despite the extensive research on the antecedents of customer engagement behaviors, the influence of intercustomer social support remains a neglected area in the context of virtual brand communities. Based on a total of 293 valid questionnaires collected via an online survey, a structural equation model and hierarchical regression analysis are used to examine the effects of intercustomer social support (informational/emotional support) on customer engagement behaviors (customer-oriented/community-oriented engagement behaviors) in virtual brand communities, as well as consider the mediating role of self-efficacy and the moderating role of interdependent self-construal in the above relationships. The empirical finding shows that informational/emotional support significantly affects customer-oriented and community-oriented engagement behaviors. Self-efficacy plays a mediating role in the relationship between informational/emotional support and customer-oriented/community-oriented engagement behaviors. Interdependent self-construal positively moderates the relationship between informational/emotional support and customer-oriented engagement behaviors and positively moderates the relationship between informational support and community-oriented engagement behaviors. This article provides a more comprehensive understanding of the relationships between intercustomer social support and customer engagement behaviors in the context of virtual brand communities, and improves the existing customer engagement behaviors management practices that are beneficial for the companies.
A Conceptual Blockchain Enhanced Information Model of Product Service Systems Framework for Sustainable Furniture
Authors: Liu Jing , Liu Zhen , Yang Qiong , Osmani Mohamed , Demian Peter
Published: December 2022

The sustainable development of the furniture industry is experiencing the challenges of energy consumption and waste disposal. Product–service systems (PSSs) have the potential to promote sustainable development and the opportunity to transition to a circular economy (CE). PSSs can bring a series of benefits to sustainable furniture, but there are still some problems to be considered, such as the safe storage and transmission of information and data and the protection of stakeholders’ rights and interests. With digitization becoming a major trend, emerging digital technologies such as blockchain (BC) are proving to have the potential to solve related problems. Therefore, this paper aims to integrate the potential roles of BC and PSSs in the lifecycle of sustainable furniture. This paper adopts a mixed quantitative and qualitative research method. Firstly, the potential relationship among furniture, PSSs, and BC was quantitatively analyzed by VOSviewer. Secondly, this paper qualitatively analyzes the lifecycle stages of sustainable furniture, the advantages of PSSs to promote sustainable furniture, and the potential of BC to enhance the PSSs information model (IM) to further promote sustainable furniture to address related challenges. Subsequently, the conceptual BC-enhanced PSSs IM (BC-PSSs) framework was constructed, which contains the high-level and the low-level of structure and process, and then reviewed and refined through pre-interview questionnaires and follow-up interviews by industry experts and scholars. In addition, discussing the contribution of the conceptual BC-PSSs framework in sustainable furniture, and the potential of BC-PSSs in quantifying design value, encouraging designers to contribute value, and exploring the potential role of BC-PSSs in supporting sustainable consumer behavior. It is the first attempt to construct a conceptual BC-enhanced PSSs IM framework for sustainable furniture from the perspective of lifecycle stages, which can serve as a reference for researchers and policymakers in relevant directions to support sustainable development, in particular contributing to the achievement of SDGs 11 (Sustainable Cities and Communities) and SDGs 12 (Responsible Consumption and Production).
Review of Improving the NOx Conversion Efficiency in Various Diesel Engines fitted with SCR System Technology
Authors: Wardana Muhammad Khristamto Aditya , Lim Ocktaeck
Published: December 2022

The diesel engine is utilized in most commercial vehicles to carry items from various firms; nevertheless, diesel engines emit massive amounts of nitrogen oxides (NOx) which are harmful to human health. A typical approach for reducing NOx emissions from diesel engines is the selective catalytic reduction (SCR) system; however, several reasons make reducing NOx emissions a challenge: urea particles frequently become solid in the injector and difficult to disseminate across the system; the injector frequently struggles to spray the smaller particles of urea; the larger urea particles from the injector readily cling to the system; it is also difficult to evaporate urea droplets because of the exhaust and wall temperatures (Tw), resulting in an increase in solid deposits in the system, uncontrolled ammonia water solution injection, and NOx emissions problems. The light-duty diesel engine (LDD), medium-duty diesel engine (MDD), heavy-duty diesel engine (HDD), and marine diesel engine use different treatments to optimize NOx conversion efficiency in the SCR system. This review analyzes several studies in the literature which aim to increase NOx conversion in different diesel engine types. The approach and methods demonstrated in this study provide a suitable starting point for future research into reducing NOx emissions from diesel engines, particularly for engines with comparable specifications.
Clinicopathological Features and Prognosis Analysis of Primary Bile Duct and Ampullary Neuroendocrine Neoplasms: A Population-Based Study from 1975 to 2016
Authors: Li Yijun , Hua Rui , He Jianjun , Zhang Huimin
Published: December 2022

Background: The main purpose of this study is to analyze the clinicopathological features and prognosis factors of bile duct and ampullary neuroendocrine neoplasms (NENs). Methods: The relevant data were collected from the SEER database from 1975 to 2016. The Kaplan–Meier curve and Cox model were used for survival analysis. The nomogram was drawn to predict the survival rate. The calibration, discrimination and clinical utility of the nomogram were evaluated by calibration curve, the concordance index (C-index) and decision curve analysis (DCA). Results: A total of 340 cases were included in our research. According to Kaplan–Meier analysis, 1-year, 3-year and 5-year of overall survival (OS) were 77.3%, 61.9% and 58.4%, while 1-year, 3-year and 5-year of the disease-specific survival (DSS) were 82.7%, 69.3% and 66.9%, respectively. The multivariable analysis results showed that age, histological grade, SEER stage and surgery were independent predictors for either OS or DSS. The calibration curve and the C-index value indicated that the nomogram was well calibrated and had good discrimination. DCA showed that the model had ideal net benefits. Conclusions: The age, histological grade, SEER stage and surgery were identified as independent prognostic variables for OS and DSS. After verification, nomogram has good predictive ability and clinical application value.
Efficacy of Immunotherapy in Second-Line Treatment of KRAS-Mutated Patients with Non-Small-Cell Lung Cancer—Data from Daily Practice
Authors: Knetki-Wróblewska Magdalena , Tabor Sylwia , Płużański Adam , Lewandowska Zofia , Tysarowski Andrzej , Pawlik Hubert , Kowalski Dariusz M. , Krzakowski Maciej
Published: December 2022

Background The implementation of next-generation sequencing (NGS) into daily practice allows for the identification of a greater number of molecular abnormalities. We aimed to confirm the benefits of immunotherapy in the group of patients with KRAS aberrations treated within clinical practice. Methods This study was a retrospective analysis of the patients (pts) treated in routine practice within the National Drug Programme in Poland. The NGS was performed using a FusionPlex Comprehensive Thyroid and Lung (CTL) kit (ArcherDx) and sequenced using a MiniSeq (Illumina). The analyses were performed with the R language environment, version 4.1.3. Results A total of 96 pts with chemotherapy-pre-treated advanced NSCLC (CS III–IV) were qualified for nivolumab or atezolizumab treatment following a molecular diagnosis by the NGS and the exclusion of EGFR and ALK gene abnormalities. A mutation in the KRAS gene was found in 26 patients (27%); among them, the variant p.Gly12Cyc (G12C) was the most common (42%). The median PFS and OS for the overall population were 2 months (95% CI: 1.8–2.75) and 10 months (95% CI: 6.9–16.2), respectively. No differences were observed in terms of the mPFS between the KRAS-mutated and KRAS wild-type (WT) patients. A trend toward a longer OS was observed in the group of patients with the KRAS mutation, but the difference was not statistically significant (p = 0.43). In the multivariate analysis, the presence of mutations in the KRAS gene had no prognostic significance, while the occurence of grade 3 toxicity and the neutrophil-to-lymphocyte ratio (NLR) > 3.5 were found as statistically significant factors. Conclusions Immunotherapy in the second-line treatment of advanced NSCLC allows for a benefit regardless of the KRAS gene mutation status. The treatment sequence, including molecularly targeted drugs such as sotorasib and adagrasib, is still discussed. The NGS is a valuable method to identify a variety of molecular abnormalities in patients with NSCLC in daily practice.
Is PET/CT Able to Predict Histology in Thymic Epithelial Tumours? A Narrative Review
Authors: Chiappetta Marco , Mendogni Paolo , Cattaneo Margherita , Evangelista Jessica , Farina Piero , Pizzuto Daniele Antonio , Annunziata Salvatore , Castello Angelo , Congedo Maria Teresa , Tabacco Diomira , Sassorossi Carolina , Castellani Massimo , Nosotti Mario , Margaritora Stefano , Lococo Filippo
Published: December 2022

Background: The usefulness of 18FDG PET/CT scan in the evaluation of thymic epithelial tumours (TETs) has been reported by several authors, but data are still limited and its application in clinical practice is far from being defined. Methods: We performed a narrative review of pertinent literature in order to clarify the role of 18FDG PET/CT in the prediction of TET histology and to discuss clinical implications and future perspectives. Results: There is only little evidence that 18FDG PET/CT scan may distinguish thymic hyperplasia from thymic epithelial tumours. On the other hand, it seems to discriminate well thymomas from carcinomas and, even more, to predict the grade of malignancy (WHO classes). To this end, SUVmax and other PET variables (i.e., the ratio between SUVmax and tumour dimensions) have been adopted, with good results. Finally, however promising, the future of PET/CT and theranostics in TETs is far from being defined; more robust analysis of imaging texture on thymic neoplasms, as well as new exploratory studies with “stromal PET tracers,” are ongoing. Conclusions: PET may play a role in predicting histology in TETs and help physicians in the management of these insidious malignancies.
Automated Bone Marrow Cell Classification for Haematological Disease Diagnosis Using Siamese Neural Network
Authors: Ananthakrishnan Balasundaram , Shaik Ayesha , Akhouri Shivam , Garg Paras , Gadag Vaibhav , Kavitha Muthu Subash
Published: December 2022

The critical structure and nature of different bone marrow cells which form a base in the diagnosis of haematological ailments requires a high-grade classification which is a very prolonged approach and accounts for human error if performed manually, even by field experts. Therefore, the aim of this research is to automate the process to study and accurately classify the structure of bone marrow cells which will help in the diagnosis of haematological ailments at a much faster and better rate. Various machine learning algorithms and models, such as CNN + SVM, CNN + XGB Boost and Siamese network, were trained and tested across a dataset of 170,000 expert-annotated cell images from 945 patients’ bone marrow smears with haematological disorders. The metrics used for evaluation of this research are accuracy of model, precision and recall of all the different classes of cells. Based on these performance metrics the CNN + SVM, CNN + XGB, resulted in 32%, 28% accuracy, respectively, and therefore these models were discarded. Siamese neural resulted in 91% accuracy and 84% validation accuracy. Moreover, the weighted average recall values of the Siamese neural network were 92% for training and 91% for validation. Hence, the final results are based on Siamese neural network model as it was outperforming all the other algorithms used in this research.
A Laboratory-Based Study on Multiple Biomarker Testing in the Diagnosis of COVID-19-Associated Pulmonary Aspergillosis (CAPA): Real-Life Data
Authors: Lass-Flörl Cornelia , Knoll Miriam , Posch Wilfried , Joannidis Michael , Mayerhöfer Timo , Breitkopf Robert , Bellmann Romuald
Published: December 2022

(1) Background: Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) raises concerns to contribute to an increased mortality. The incidence of CAPA varies widely within hospitals and countries, partly because of difficulties in obtaining a reliable diagnosis. (2) Methods: Here, we assessed Aspergillus culture-positive and culture-negative respiratory tract specimens via direct fungal microscopy (gold standard) and compared the results with galactomannan enzyme immunoassay (GM-EIA) and Aspergillus PCR. (3) Results: 241 respiratory samples from patients suffering from SARS-CoV-2 pneumonia were evaluated. Results showed both diagnostic tools, Aspergillus PCR and GM-EIA, to be positive or negative displaying a sensitivity of 0.90, a specificity of 0.77, a negative predictive value (NPV) of 0.95, and a positive predictive value (PPV) of 0.58 in Aspergillus sp. culture and microscopic-positive specimens. Non-bronchoalveolar lavage (BAL) samples, obtained within a few days from the same patient, showed a high frequency of intermittent positive or negative GM-EIA or Aspergillus PCR results. Positivity of a single biomarker is insufficient for a proper diagnosis. A broad spectrum of Aspergillus species was detected. (4) Conclusions: Our study highlights the challenges of combined biomarker testing as part of diagnosing CAPA. From the results presented, we highly recommend the additional performance of direct microscopy in respiratory specimens to avoid overestimation of fungal infections by applying biomarkers.
COVID-19 Patients in the COVID-19 Recovery and Engagement (CORE) Clinics in the Bronx
Authors: Eligulashvili Anna , Darrell Megan , Miller Carolyn , Lee Jeylin , Congdon Seth , Lee Jimmy S. , Hsu Kevin , Yee Judy , Hou Wei , Islam Marjan , Duong Tim Q.
Published: December 2022

Background: Early in the pandemic, we established COVID-19 Recovery and Engagement (CORE) Clinics in the Bronx and implemented a detailed evaluation protocol to assess physical, emotional, and cognitive function, pulmonary function tests, and imaging for COVID-19 survivors. Here, we report our findings up to five months post-acute COVID-19. Methods: Main outcomes and measures included pulmonary function tests, imaging tests, and a battery of symptom, physical, emotional, and cognitive assessments 5 months post-acute COVID-19. Findings: Dyspnea, fatigue, decreased exercise tolerance, brain fog, and shortness of breath were the most common symptoms but there were generally no significant differences between hospitalized and non-hospitalized cohorts (p > 0.05). Many patients had abnormal physical, emotional, and cognitive scores, but most functioned independently; there were no significant differences between hospitalized and non-hospitalized cohorts (p > 0.05). Six-minute walk tests, lung ultrasound, and diaphragm excursion were abnormal but only in the hospitalized cohort. Pulmonary function tests showed moderately restrictive pulmonary function only in the hospitalized cohort but no obstructive pulmonary function. Newly detected major neurological events, microvascular disease, atrophy, and white-matter changes were rare, but lung opacity and fibrosis-like findings were common after acute COVID-19. Interpretation: Many COVID-19 survivors experienced moderately restrictive pulmonary function, and significant symptoms across the physical, emotional, and cognitive health domains. Newly detected brain imaging abnormalities were rare, but lung imaging abnormalities were common. This study provides insights into post-acute sequelae following SARS-CoV-2 infection in neurological and pulmonary systems which may be used to support at-risk patients and develop effective screening methods and interventions.
Architecture of Emergency Communication Systems in Disasters through UAVs in 5G and Beyond
Authors: Shah A. F. M. Shahen
Published: December 2022

Unmanned aerial vehicles (UAVs) are valued in 5G and 6G networks due to their communication capabilities, low cost, and flexible deployment. Recently, UAV-aided emergency networks in disasters have been designed where one single large UAV is used. Compared with a single large UAV, Flying Ad Hoc Networks (FANETs) with small UAVs have many benefits. Therefore, instead of a single large UAV, a FANET is proposed in this paper. To take full advantage of their services, UAVs must be able to communicate efficiently with each other and with existing networking infrastructures. However, high node mobility is one of the main characteristics of FANETs, which can result in rapid topology changes with frequent link breakage and unstable communications that cause collision and packet loss. As an alternative, networks can be broken up into smaller groups or clusters to control their topology efficiently and reduce channel contention. In this study, a novel cluster-based mechanism is proposed for FANETs. The process of cluster management is described. The IEEE 802.11 backoff method is specifically intended for direct communications and is not appropriate for cluster-based communications. Therefore, a new backoff mechanism is proposed based on cluster size to optimize performance. An analytical study using the Markov chain model is presented to explore the performance of the proposed mechanism. The study takes into account Nakagami-m fading channels. Performance-influencing parameters are taken into consideration and the relationships among these parameters as well as performance metrics such as throughput, packet dropping rate, outage probability, and delay are obtained. Furthermore, simulation results are provided which verify the analytical studies. A quantitative comparison with current cluster-based methods is also presented. The simulation results show that the suggested technique enhances system performance and complies with the safety message delay constraint of 100 ms.
Quantum-Solving Algorithm for d’Alembert Solutions of the Wave Equation
Authors: Zhu Yuanye
Published: December 2022

When faced with a quantum-solving problem for partial differential equations, people usually transform such problems into Hamiltonian simulation problems or quantum-solving problems for linear equation systems. In this paper, we propose a third approach to solving partial differential equations that differs from the two approaches. By using the duality quantum algorithm, we construct a quantum-solving algorithm for solving the first-order wave equation, which represents a typical class of partial differential equations. Numerical results of the quantum circuit have high precision consistency with the theoretical d’Alembert solution. Then the routine is applied to the wave equation with either a dissipation or dispersion term. As shown by complexity analysis for all these cases of the wave equation, our algorithm has a quadratic acceleration for each iteration compared to the classical algorithm.
Strong Generalized Speech Emotion Recognition Based on Effective Data Augmentation
Authors: Tao Huawei , Shan Shuai , Hu Ziyi , Zhu Chunhua , Ge Hongyi
Published: December 2022

The absence of labeled samples limits the development of speech emotion recognition (SER). Data augmentation is an effective way to address sample sparsity. However, there is a lack of research on data augmentation algorithms in the field of SER. In this paper, the effectiveness of classical acoustic data augmentation methods in SER is analyzed, based on which a strong generalized speech emotion recognition model based on effective data augmentation is proposed. The model uses a multi-channel feature extractor consisting of multiple sub-networks to extract emotional representations. Different kinds of augmented data that can effectively improve SER performance are fed into the sub-networks, and the emotional representations are obtained by the weighted fusion of the output feature maps of each sub-network. And in order to make the model robust to unseen speakers, we employ adversarial training to generalize emotion representations. A discriminator is used to estimate the Wasserstein distance between the feature distributions of different speakers and to force the feature extractor to learn the speaker-invariant emotional representations by adversarial training. The simulation experimental results on the IEMOCAP corpus show that the performance of the proposed method is 2–9% ahead of the related SER algorithm, which proves the effectiveness of the proposed method.
Steps towards the Integration of the Gender and Sex Dimension in R&I: The Case of a Public University
Authors: Jordão Carina , Diogo Sara
Published: December 2022

Gender equality has been placed at the centre of European research policy recently. The inclusion of gender and sex considerations into research and innovation (R&I) is an essential factor for scientific excellence and a key requirement for producing knowledge that can benefit society as a whole. However, the adoption of a gender/sex dimension is still a problematic issue in several Research Performance Organisations (RPOs) of European Union (EU) countries. Through the experience of implementing a gender equality plan (GEP) within the scope of a Horizon 2020 (H2020) project at a public Portuguese university (PPU), this study aims to explore the EU policies’ impact on the integration of the gender dimension in research, considering both institutional policies and scientific outputs. To achieve the purpose of the study, a mixed approach that combines a qualitative analysis of institutional documents and data collected through interviews with a quantitative analysis of secondary data is used. The implementation of the H2020 project brought the issue of gender inequality to the institutional agenda of the PPU under study and the formalisation of the GEP marked a transition point towards an integrated and intersectional approach that embraces gender dimension concerns in R&I. This transition coincided with a period characterised by an increase in the scientific outputs incorporating the ‘gender/sex dimension’, which may highlight the importance of European policies in stimulating and accelerating the introduction of the gender dimension in scientific practices in RPOs.
Torrent Poisoning Protection with a Reverse Proxy Server
Authors: Godinho António , Rosado José , Sá Filipe , Caldeira Filipe , Cardoso Filipe
Published: December 2022

A Distributed Denial-of-Service attack uses multiple sources operating in concert to attack a network or site. A typical DDoS flood attack on a website targets a web server with multiple valid requests, exhausting the server’s resources. The participants in this attack are usually compromised/infected computers controlled by the attackers. There are several variations of this kind of attack, and torrent index poisoning is one. A Distributed Denial-of-Service (DDoS) attack using torrent poisoning, more specifically using index poisoning, is one of the most effective and disruptive types of attacks. These web flooding attacks originate from BitTorrent-based file-sharing communities, where the participants using the BitTorrent applications cannot detect their involvement. The antivirus and other tools cannot detect the altered torrent file, making the BitTorrent client target the webserver. The use of reverse proxy servers can block this type of request from reaching the web server, preventing the severity and impact on the service of the DDoS. In this paper, we analyze a torrent index poisoning DDoS to a higher education institution, the impact on the network systems and servers, and the mitigation measures implemented.
Life Cycle Assessment of Hydrogen Production from Coal Gasification as an Alternative Transport Fuel
Authors: Burchart Dorota , Gazda-Grzywacz Magdalena , Grzywacz Przemysław , Burmistrz Piotr , Zarębska Katarzyna
Published: December 2022

The gasification of Polish coal to produce hydrogen could help to make the country independent of oil and gas imports and assist in the rational energy transition from gray to green hydrogen. When taking strategic economic or legislative decisions, one should be guided not only by the level of CO2 emissions from the production process, but also by other environmental impact factors obtained from comprehensive environmental analyses. This paper presents an analysis of the life cycle of hydrogen by coal gasification and its application in a vehicle powered by FCEV cells. All the main stages of hydrogen fuel production by Shell technology, as well as hydrogen compression and transport to the distribution point, are included in the analyses. In total, two fuel production scenarios were considered: with and without sequestration of the carbon dioxide captured in the process. Life cycle analysis was performed according to the procedures and assumptions proposed in the FC-Hy Guide, Guidance Document for performing LCAs on Fuel Cells and H₂ Technologies by the CML baseline method. By applying the CO2 sequestration operation, the GHG emissions rate for the assumed functional unit can be reduced by approximately 44% from 34.8 kg CO2-eq to 19.5 kg CO2-eq, but this involves a concomitant increase in the acidification rate from 3.64·10−2 kg SO2-eq to 3.78·10−2 kg SO2-eq, in the eutrophication index from 5.18·10−2 kg PO3−4-eq to 5.57·10−2 kg PO3−4-eq and in the abiotic depletion index from 405 MJ to 414 MJ and from 1.54·10−5 kg Sbeq to 1.61·10−5 kg Sbeq.
Cistus ladanifer as a Potential Feedstock for Biorefineries: A Review
Authors: Alves-Ferreira Júnia , Duarte Luís C. , Fernandes Maria C. , Pereira Helena , Carvalheiro Florbela
Published: December 2022

Cistus ladanifer (rockrose) is a widespread shrub species in the Mediterranean region well known due to its production of labdanum gum, especially in the hot season. Its leaves and branches can be subjected to different extraction and distillation processes to produce various types of extracts. The natural extracts of C. ladanifer have several applications, especially in the perfumery and cosmetics sector. C. ladanifer extracts, in addition to presenting interesting odoriferous properties, are also known for their bioactive properties, such as antioxidant and antimicrobial. Use of this species in animal feed or phytostabilisation of mining areas has also been successfully applied. On the other hand, the lignin and polysaccharides that are the major fractions from Cistus residues can be relevant sources of high-value products in a biorefinery framework. Recently, it has been reported that the residues obtained from the essential oil industry can sustain production of significant amounts of other marketable products, namely phenolic compounds, oligomeric and monomeric sugars, lignin, and lactic acid. All these applications show the potential of C. ladanifer as a raw material to be fully valued in a biorefinery context, contributing to important revenues and generating an associated marketable biobased product portfolio.
State of the Art Monte Carlo Method Applied to Power System Analysis with Distributed Generation
Authors: Abud Tiago P. , Augusto Andre A. , Fortes Marcio Z. , Maciel Renan S. , Borba Bruno S. M. C.
Published: December 2022

Traditionally, electric power systems are subject to uncertainties related to equipment availability, topological changes, faults, disturbances, behaviour of load, etc. In particular, the dissemination of distributed generation (DG), especially those based on renewable sources, has introduced new challenges to power systems, adding further randomness to the management of this segment. In this context, stochastic analysis could support planners and operators in a more appropriate manner than traditional deterministic analysis, since the former is able to properly model the power system uncertainties. The objective of this work is to present recent achievements of one of the most important techniques for stochastic analysis, the Monte Carlo Method (MCM), to study the technical and operational aspects of electric networks with DG. Besides covering the DG topic itself, this paper also addresses emerging themes related to smart grids and new technologies, such as electric vehicles, storage, demand response, and electrothermal hybrid systems. This review encompasses more than 90 recent articles, arranged according to the MCM application and the type of analysis of power systems. The majority of the papers reviewed apply the MCM within stochastic optimization, indicating a possible trend.
Distributed Module-Based Power Supply Enhancement System for 3 kV DC Traction
Authors: Jefimowski Włodzimierz , Drążek Zbigniew
Published: December 2022

This paper presents a conception of 3 kV DC traction power system based on distribution sources, as an alternative to traditional traction substation. The system consists of supplying modules (SM) installed along the electrified railway line, the distance between adjacent SMs are much shorter, than between traditional traction substations in 3 kV system. Each SM consists of energy storage system (ESS), and could be charged from adjacent, traditional traction substation via catenary, via medium voltage supplying lines, renewable power sources or by energy recuperation. In the article, the main parameters of the proposed supplying system operation have been compared with parameters of the system with traditional traction substation. For this purpose, in a case study, comparison analysis has been carried out for energy losses in catenary, 15-min peak power demand as well as the cost of the system installation. At the end, the reliability analysis has been carried out for proposed distribution power supply system and for traditional one.
How Do Methane, Carbon Dioxide or Fatty Acids Affect Waxy Crude Oils?
Authors: Sousa Ana M. , Ribeiro Tiago P. , Pereira Maria J. , Matos Henrique A.
Published: December 2022

In the oil and gas industry, wax formation and deposition are common problems, particularly during production and transportation. To better understand the expected behaviour of a given waxy crude oil and consequently select the best solution to prevent wax deposition, it is vital to conduct laboratory tests or numerical simulations to model its performance. For a Brazilian oil field, the phase behaviour of 17 crude oils was modelled using Multiflash software. To tune the model, laboratory tests were used, including true boiling point curves and viscosity tests. This study followed two stages: the first allowed characterization of the wax appearance temperature (WAT) and determination of the expected precipitation curves for these crude samples, and the second stage was evaluation of the impact on wax precipitation after the addition of methane (CH4), carbon dioxide (CO2) or fatty acid (CH3(CH2)nCOOH). Results showed that WAT varied between 47.5 °C and 51.6 °C for these crude oil samples at atmospheric pressure, considering the differential scanning calorimetry (DSC) method. Furthermore, the percentage of wax mass formed varied between 13.3% and 18.3%. By adding the aforementioned chemicals as an inhibitor, it is possible to observe a reduction in the paraffin precipitation tendency. Inhibition was compared in terms of effectiveness between the chemicals studied, and it was concluded that adding myristic acid (C14:0), oleic acid (C18:1), palmitic acid (C16:0), or lauric acid (C12:0) was the most effective in reducing the WAT value. In fact, when adding 25% mole fraction, CH4 and CO2 can reduce the WAT value by up to 4%, but the results are strongly dependent on the fluid pressure. Myristic acid was the most effective in reducing the WAT value by up to 5%, and the results were less pressure dependent.
Data Processing with Predictions in LoRaWAN
Authors: Nowak Mariusz , Różycki Rafał , Waligóra Grzegorz , Szewczyk Joanna , Sobiesierski Adrian , Sot Grzegorz
Published: December 2022

In this paper, the potential to reduce the energy consumption of end devices operating in a LoRaWAN (long-range wide-area network) is studied. An increasing number of IoT components communicating over wireless networks are powered by external sources. Designers of communication systems are concerned with extending the operating time of IoT, hence the need to look for effective methods to reduce power consumption. This article proposes two algorithms to reduce the energy consumption of end devices. The first algorithm is based on the use of a measured value prediction, and the second algorithm optimizes the antenna gain of the end device. Both algorithms have been implemented and tested. The test experiments for reducing energy consumption were conducted independently for the cases with the first algorithm and then for the second algorithm. The possibilities of reducing energy consumption were also investigated for the case when both algorithms work together. The proposed predictive algorithm reduced energy consumption the least. Better results in reducing energy consumption were guaranteed by the algorithm optimizing antenna power. The greatest gain was achieved using both algorithms simultaneously. Tests of the developed algorithms, in laboratory conditions and in conditions with a change in the distance between the end device and the LoRa gateway, confirmed the possibility of reducing energy consumption during the transmission of measurement data in a low-energy wireless LoRaWAN. Reducing electric energy consumption by even a few percent for a single device can result in significant savings on a global scale.
Design of Selective TPV Thermal Emitters Based on Bayesian Optimization Nesting Simulated Annealing
Authors: Liu Zejia , Zhang Zigui , Xie Peifeng , Miao Zibo
Published: December 2022

It is vital to further improve the design of TPV thermal emitters since the energy efficiency of thermophotovoltaic (TPV) systems is still not adequately high. In this paper, we propose a novel evaluator for the optimization of TPV thermal emitters, namely the percentage of effective figure (PEF) to replace the figure of merit (FOM). The associated algorithm, Bayesian optimization nesting simulated annealing (BOnSA), is developed to achieve better performance. By searching throughout the whole parameter space and then optimizing in a reduced space, BOnSA can lead to a satisfactory solution numerically for GaSb photovoltaic (PV) cells. When designing the emitter, the aperiodic material structure with an anti-reflection substructure and Fabry–Perot etalon is constructed from the material candidates. In particular, one of the optimal structures determined by BOnSA is {SiO2, ZnS, Ge, MgF2, W, Si, SiO2, W} with the value of PEF=0.822, which is better than the previous work by comparison. Moreover, by applying BOnSA to various structures, we have obtained higher values of PEF with less time cost, which thus verifies the efficiency and scalability of BOnSA. The results of our paper show that BOnSA provides an effective approach to the thickness optimization problem and that BOnSA is applicable in other relevant scenarios.