bluuebunny/crossref_metadata_2025 huggingface dataset:
Tumor-Associated Macrophages in Multiple Myeloma: Key Role in Disease Biology and Potential Therapeutic Implications
Authors: Cencini Emanuele , Sicuranza Anna , Ciofini Sara , Fabbri Alberto , Bocchia Monica , Gozzetti Alessandro
Published: June 2023

Multiple myeloma (MM) is characterized by multiple relapse and, despite the introduction of novel therapies, the disease becomes ultimately drug-resistant. The tumor microenvironment (TME) within the bone marrow niche includes dendritic cells, T-cytotoxic, T-helper, reactive B-lymphoid cells and macrophages, with a complex cross-talk between these cells and the MM tumor cells. Tumor-associated macrophages (TAM) have an important role in the MM pathogenesis, since they could promote plasma cells proliferation and angiogenesis, further supporting MM immune evasion and progression. TAM are polarized towards M1 (classically activated, antitumor activity) and M2 (alternatively activated, pro-tumor activity) subtypes. Many studies demonstrated a correlation between TAM, disease progression, drug-resistance and reduced survival in lymphoproliferative neoplasms, including MM. MM plasma cells in vitro could favor an M2 TAM polarization. Moreover, a possible correlation between the pro-tumor effect of M2 TAM and a reduced sensitivity to proteasome inhibitors and immunomodulatory drugs was hypothesized. Several clinical studies confirmed CD68/CD163 double-positive M2 TAM were associated with increased microvessel density, chemoresistance and reduced survival, independently of the MM stage. This review provided an overview of the biology and clinical relevance of TAM in MM, as well as a comprehensive evaluation of a potential TAM-targeted immunotherapy.
Folliculosebaceous Cystic Hamartoma with Spindle Cell Lipomatous and Neural Components
Authors: Urso Carmelo , Yarygina Marina
Published: June 2023

Folliculosebaceous cystic hamartoma is a cutaneous malformation composed of a cystic folliculosebaceous structure associated with mesenchymal elements, generally consisting of fibrous stroma, adipocytes and small vascular channels. We report the case of a 55-year-old female patient with a cutaneous nodule of the right nasal wing. Microscopically, the lesion showed a dilated hair follicle with multiple sebaceous glands, surrounded by a mesenchymal component composed of fibromyxoid stroma, spindle cells, mature-appearing adipocytes and collagen bundles, resembling spindle cell lipoma, associated with an additional neural component, consisting of small nerve bundles. In folliculosebaceous cystic hamartoma, the association of spindle cell lipomatous and neural components has not previously reported.
Concentrations of Serum Brain Injury Biomarkers Following SARS-CoV-2 Infection in Individuals with and without Long-COVID—Results from the Prospective Population-Based COVI-GAPP Study
Authors: Telser Julia , Grossmann Kirsten , Weideli Ornella C. , Hillmann Dorothea , Aeschbacher Stefanie , Wohlwend Niklas , Velez Laura , Kuhle Jens , Maleska Aleksandra , Benkert Pascal , Risch Corina , Conen David , Risch Martin , Risch Lorenz
Published: June 2023

It is unknown whether neurological symptoms are associated with brain injury after SARS-CoV-2 infections and whether brain injury and related symptoms also emerge in Long-COVID patients. Biomarkers such as serum neurofilament light chain (sNfL) and glial fibrillary acidic protein (sGFAP) can be used to elucidate neuro-axonal and astroglial injuries. We investigated whether these biomarkers are associated with COVID-19 infection status, associated symptoms and Long-COVID. From 146 individuals of the general population with a post-acute, mild-to-moderate SARS-CoV-2 infection, sNfL and sGFAP were measured before, during and after (five and ten months) the infection. Individual symptoms and Long-COVID status were assessed using questionnaires. Neurological associated symptoms were described for individuals after a mild and moderate COVID-19 infection; however, sNfL (p = 0.74) and sGFAP (p = 0.24) did not change and were not associated with headache (p = 0.51), fatigue (p = 0.93), anosmia (p = 0.77) or ageusia (p = 0.47). In Long-COVID patients, sGFAP (p = 0.038), but not sNfL (p = 0.58), significantly increased but was not associated with neurological associated symptoms. Long-COVID status, but not post-acute SARS-CoV-2 infections, may be associated with astroglial injury/activation, even if neurological associated symptoms were not correlated.
Oxygen Requirement in Overweight/Obese Kidney Transplant Recipients with COVID-19: An Observational Cohort Study
Authors: Veronese-Araújo Alexandre , de Lucena Débora D. , Aguiar-Brito Isabella , Modelli de Andrade Luís Gustavo , Cristelli Marina P. , Tedesco-Silva Hélio , Medina-Pestana José O. , Rangel Érika B.
Published: June 2023

Introduction: Obesity is one of the components of the cardiometabolic syndrome that contributes to COVID-19 progression and mortality. Immunosuppressed individuals are at greater risk of the COVID-19 burden. Therefore, we sought to investigate the impact of the combination of overweight/obesity and kidney transplant on oxygen (O2) requirements in the COVID-19 setting. Methods: Retrospective analysis of 284 kidney transplant recipients (KTRs) from March/2020 to August/2020 in a single center. We investigated the risk factors associated with O2 requirements in overweight/obese KTRs. Results: Overall, 65.1% had a BMI (body mass index) ≥ 25 kg/m2, 52.4% were male, the mean age was 53.3 ± 11 years old, 78.4% had hypertension, and 41.1% had diabetes mellitus. BMI was an independent risk factor for O2 requirements (OR = 1.07, p = 0.02) alongside age, lymphopenia, and hyponatremia. When overweight/obese KTRs were older, smokers, they presented higher levels of lactate dehydrogenase (LDH), and lower levels of estimated glomerular filtration rate (eGFR), lymphocytes, and sodium at admission, and they needed O2 more often. Conclusion: Being overweight/obese is associated with greater O2 requirements in KTRs, in particular in older people and smokers, with worse kidney allograft functions, more inflammation, and lower sodium levels. Therefore, the early identification of factors that predict a worse outcome in overweight/obese KTRs affected by COVID-19 contributes to risk stratification and therapeutic decisions.
Popularity and Entropy in Friendship and Enmity Networks in Classrooms
Authors: Sánchez-Espinosa Diego B. , Hernández-Ramírez Eric , del Castillo-Mussot Marcelo
Published: June 2023

Looking for regular statistical trends of relations in schools, we constructed 42 independent weighted directed networks of simultaneous friendship and animosity from surveys we made in the Mexico City Metropolitan area in classrooms with students of different ages and levels by asking them to nominate and order five friends and five foes. However, the data show that older students nominated fewer than the five required five foes. Although each classroom was independent of the others, we found several general trends involving students of different ages and grade levels. In all classrooms, friendship entropy was found to be higher than enmity entropy, indicating that fewer students received enmity links than received friendship nominations. Popular agents exhibited more reciprocal nominations among themselves than less popular agents, and opposite-sex friendships increased with age.
Hamming Distance Optimized Underwater Acoustic OTFS-IM Systems
Authors: Guo Xiaopeng , Wang Biao , Zhu Yunan , Fang Zide , Han Zhaoyue
Published: June 2023

The orthogonal time frequency space (OTFS) modulation technique can provide reliable communication in time-varying channels. Due to the dispersive characteristics of underwater acoustic channels, this paper proposes an OTFS-IM underwater acoustic communication system based on Hamming distance optimization to reduce the impact of dispersion in underwater acoustic communication. Firstly, the OTFS-IM underwater acoustic communication system is introduced, which introduces index modulation into the Delay–Doppler (DD) domain to make the OTFS system have stronger anti-Delay–Doppler capability. In contrast, since there is index sequence redundancy in a specific index combination, a Hamming distance optimization model is used to eliminate the redundant combination in the specific index combination sequence and further improve the bit error rate performance of the system. In addition, the Hamming distance optimized OTFS-IM underwater acoustic communication system is verified by simulation analysis. The results show that the proposed Hamming distance optimized OTFS-IM can achieve more reliable bit error rate performance.
Backdoor Attack against Face Sketch Synthesis
Authors: Zhang Shengchuan , Ye Suhang
Published: June 2023

Deep neural networks (DNNs) are easily exposed to backdoor threats when training with poisoned training samples. Models using backdoor attack have normal performance for benign samples, and possess poor performance for poisoned samples manipulated with pre-defined trigger patterns. Currently, research on backdoor attacks focuses on image classification and object detection. In this article, we investigated backdoor attacks in facial sketch synthesis, which can be beneficial for many applications, such as animation production and assisting police in searching for suspects. Specifically, we propose a simple yet effective poison-only backdoor attack suitable for generation tasks. We demonstrate that when the backdoor is integrated into the target model via our attack, it can mislead the model to synthesize unacceptable sketches of any photos stamped with the trigger patterns. Extensive experiments are executed on the benchmark datasets. Specifically, the light strokes devised by our backdoor attack strategy can significantly decrease the perceptual quality. However, the FSIM score of light strokes is 68.21% on the CUFS dataset and the FSIM scores of pseudo-sketches generated by FCN, cGAN, and MDAL are 69.35%, 71.53%, and 72.75%, respectively. There is no big difference, which proves the effectiveness of the proposed backdoor attack method.
Revisiting the Impact of Dams on Malaria and Agriculture
Authors: Mary Sebastien , Craven Kyle , Stoler Avraham , Shafiq Sarah
Published: June 2023

We estimate the effect of large dams on malaria incidence in India between 1975 and 1995. We combine instrumental variables approach with a panel model with unobserved common factors allowing us to fully capture the endogeneity of dam location and unobserved time-varying heterogeneity. Dams result in increased malaria incidence in districts where dams are located and in downstream areas. We find that the construction of a large dam increases a district’s annual malaria incidence by about 0.9 to 1.4 percent, and by about 1 to 1.5 percent in downstream districts. We also find that this malaria-increasing effect of dams persists over time. Our results imply that the construction of dams in malaria-sensitive areas should be coupled with direct interventions, such as the wide deployment of insecticide-treated nets or the roll-out of future vaccines. Furthermore, we examine the contribution of agricultural development to this malaria-increasing effect of dams. We find that dam construction benefits agriculture in the vicinity of dams, as well as in downstream areas. These positive effects are driven by increased irrigation and cultivation in the vicinity of dams, while they are driven by changes in cropping patterns in downstream areas, where the cultivation of high-yielding variety crops increases. Finally, a back-of-the-envelope calculation suggests that the agricultural production gains from dam construction dominate the economic losses resulting from increased malaria.
Analytical Approach to Improve the Performance of a Fully Integrated Class-F Power Amplifier with 0.13 µm BiCMOS Technology Using Drain–Bulk Capacitor Modulation
Authors: Traiche Smail , Trabelsi Mohamed , Bououden Ali , Yagoub Mustapha C. E.
Published: June 2023

This article reports a novel technique based on drain–bulk capacitor modulation to improve the performance design of a class-F power amplifier (PA) used in low-power transceivers based on the I-Q amplitude modulation technique considering linearity–efficiency–miniaturization trade-offs. This idea is carried out by implementing a tuned capacitor in parallel with a cascode transistor on the output of the power stage to enhance the shape of the voltage–current amplitudes of the class-F PA by creating a new harmonic current component. Simulated results were obtained for the power back-off region of the proposed configuration, with an output power, power gain and power-added efficiency of 8 dBm (+ 5 dBm)B, 19 dB (+ 5 dB)B and 45% (+ 5% to 10%)B, respectively. In addition, post-layout simulations revealed a similar level of output power, a power gain of a 20 dB and a 28% power-added efficiency for an added capacitance equal to 1.3 pF. Class-F PA is implemented on a 732×605 μm2 chip’s surface. (B: indicates the improved values in the power back-off region).
Emotion Classification Based on CWT of ECG and GSR Signals Using Various CNN Models
Authors: Dessai Amita , Virani Hassanali
Published: June 2023

Emotions expressed by humans can be identified from facial expressions, speech signals, or physiological signals. Among them, the use of physiological signals for emotion classification is a notable emerging area of research. In emotion recognition, a person’s electrocardiogram (ECG) and galvanic skin response (GSR) signals cannot be manipulated, unlike facial and voice signals. Moreover, wearables such as smartwatches and wristbands enable the detection of emotions in people’s naturalistic environment. During the COVID-19 pandemic, it was necessary to detect people’s emotions in order to ensure that appropriate actions were taken according to the prevailing situation and achieve societal balance. Experimentally, the duration of the emotion stimulus period and the social and non-social contexts of participants influence the emotion classification process. Hence, classification of emotions when participants are exposed to the elicitation process for a longer duration and taking into consideration the social context needs to be explored. This work explores the classification of emotions using five pretrained convolutional neural network (CNN) models: MobileNet, NASNetMobile, DenseNet 201, InceptionResnetV2, and EfficientNetB7. The continuous wavelet transform (CWT) coefficients were detected from ECG and GSR recordings from the AMIGOS database with suitable filtering. Scalograms of the sum of frequency coefficients versus time were obtained and converted into images. Emotions were classified using the pre-trained CNN models. The valence and arousal emotion classification accuracy obtained using ECG and GSR data were, respectively, 91.27% and 91.45% using the InceptionResnetV2 CNN classifier and 99.19% and 98.39% using the MobileNet CNN classifier. Other studies have not explored the use of scalograms to represent ECG and GSR CWT features for emotion classification using deep learning models. Additionally, this study provides a novel classification of emotions built on individual and group settings using ECG data. When the participants watched long-duration emotion elicitation videos individually and in groups, the accuracy was around 99.8%. MobileNet had the highest accuracy and shortest execution time. These subject-independent classification methods enable emotion classification independent of varying human behavior.
Hardware in the Loop Simulation for Bottle Sealing Process Virtualized on Unity 3D
Authors: Villarroel Adrián , Toapanta Danny , Naranjo Santiago , Ortiz Jessica S.
Published: June 2023

This paper details the design and implementation of a virtualized bottle sealing plant using the Hardware in the Loop technique, for which it is divided into two parts: (i) Software consists of a virtualized environment in Unity 3D to visualize its behavior in real time; and (ii) Hardware was implemented through a PLC S7 1200 AC/DC/RLY (Programmable Logic Controller), which is responsible for the automation of the plant, programmed through the software TIA Portal V16 (Totally Integrated Automation Portal) and a control panel with buttons and indicator lights. The two developed parts communicate through bidirectional TCP/IP Ethernet, achieving a Server–Client architecture. For real-time monitoring and visualization, a SCADA (Supervisory Control and Data Acquisition) system implemented in InTouch is considered. In addition, the data acquisition is accomplished through the OPC (Open Platform Communication) server; the functionality of the OPC server is to transmit the information generated in an industrial plant at the enterprise level. This allows the process to execute its tasks of connectivity of automated processes and their supervision, as well as having scalability so that more tags can be included in other processes over time and ensure its operability.
SPANoF: A Scalable and Performant Architecture for NVMeoF-Based Storage Disaggregation with Limited Network Resources
Authors: Xiao Yuyang , Xie Xuchao , Li Qiong , Qiao Xinghan , Gu Wenhao
Published: June 2023

NVMe-over-Fabrics (NVMeoF) is expected to have high-performance and be highly scalable for disaggregating NVMe SSDs to High-Speed Network (HSN)-attached storage servers, thus the aggregated NVMe SSDs in storage servers can be elastically allocated to remote host servers for better utilization. However, due to the well-known connection scalability issue of RDMA NICs (RNICs), RDMA-enabled HSN can only provide a limited scale of performant Queue Pairs (QPs) for NVMeoF I/O queues to transfer capsule and data between the storage server and remote host servers. However, in current NVMeoF implementations, multiplexing multiple NVMeoF I/O queues onto a single RNIC QP is not supported yet. In this paper, we investigate how NVMeoF capsule and data transfers are performed efficiently over HSN with a limited number of RNIC QPs, and propose SPANoF, a Scalable and Performant Architecture for NVMe-over-Fabrics. SPANoF dissolves the intrinsic one-to-one mapping relationship between NVMeoF I/O queues and RNIC QPs, allocates a dedicated send-list for each NVMeoF I/O queue rather than for each RNIC QP, transfers NVMeoF capsules and data in send-lists with a QP-centric manner to remove lock-contention overhead, and polls for transfer completion notifications to remove interrupt-caused context switch overhead. We implemented SPANoF in the Linux kernel and evaluated it by the FIO benchmarks. Our experimental results demonstrate that SPANoF can avoid the performance collapses for commercial RNICs with a limited number of performant QPs and avoid the system crash for domain-specific RNICs with only limited-scale available QPs. Compared with the native NVMeoF implementation in Linux kernel, SPANoF can saturate an RNIC of the storage server with only three RNIC QPs of the remote host server. Compared with lock-based QP-sharing mechanisms, SPANoF improves bandwidth by up to 1.55× under 64 KB sequential write requests, improves throughput by up to 4.18× and reduces the average latency by 28.31% under 4 KB random read requests.
Decision Support Tool for Electric Power Generation Development: A Feasibility Analysis for a Nigerian Case
Authors: Otobo Justicia , Hartungi Rusdy , Ibraheem Yusuf , Estebsari Abouzar
Published: June 2023

Electricity is a crucial component of sustainable development in developing countries, providing opportunities to supply low-cost clean energy to their populations. This paper presents a decision support tool for the Nigerian case, allowing users to rank different enhancement options to meet future scenarios. The tool enables feasibility checks on infrastructure capacity and can handle various generation options, including low-cost renewable resources. It is easy to use for non-experts and decision-makers and incorporates an optimal power flow algorithm to minimize costs. Demonstrated on a modified IEEE 30-bus system informed by Nigerian scenarios, this tool can provide policymakers with valuable insights for long-term investment decisions and facilitate the delivery of low-cost clean energy to developing countries.
An Evolutionary Game Theory-Based Method to Mitigate Block Withholding Attack in Blockchain System
Authors: Liu Xiao , Huang Zhao , Wang Quan , Wan Bo
Published: June 2023

Consensus algorithms are the essential components of blockchain systems. They guarantee the blockchain’s fault tolerance and security. The Proof of Work (PoW) consensus algorithm is one of the most widely used consensus algorithms in blockchain systems, using computational puzzles to enable mining pools to compete for block rewards. However, this excessive competition for computational power will bring security threats to blockchain systems. A block withholding (BWH) attack is one of the most critical security threats blockchain systems face. A BWH attack obtains the reward of illegal block extraction by replacing full proof with partial mining proof. However, the current research on the BWH game could be more extensive, considering the problem from the perspective of a static game, and it needs an optimal strategy that dynamically reflects the mining pool for multiple games. Therefore, to solve the above problems, this paper uses the method of the evolutionary game to design a time-varying dynamic game model through the degree of system supervision and punishment. Based on establishing the game model, we use the method of replicating dynamic equations to analyze and find the optimal strategy for mining pool profits under different BWH attacks. The experimental results demonstrate that the mining pools will choose honest mining for the best profit over time under severe punishment and high supervision. On the contrary, if the blockchain system is supervised with a low penalty, the mining pools will eventually choose to launch BWH attacks against each other to obtain the optimal mining reward. These experimental results also prove the validity and correctness of our model and solution.
Robust RPPG Method Based on Reference Signal Envelope to Improve Wave Morphology
Authors: Sun Lu , Wang Liting , Shen Wentao , Liu Changsong , Bai Fengshan
Published: June 2023

Remote physiological monitoring has become increasingly important in improving quality of life, with remote photoplethysmography (RPPG) being a popular choice. This paper introduces an envelope–based method for RPPG channels to improve wave morphology of the collected signal based on the reference signal from finger PPG. Using a model consistent with physiological and optical principles, the authors divided the signal into linear superpositions, comprising pulse, constant, and disturbance components. The correlation coefficients were used to calculate a linear combination of Red–Green–Blue (RGB) channels to approximate the envelope shape of the reference PPG signal. Experiments with different light intensities and stability were designed to compare the envelope approximation ability and robustness of the proposed method with some common methods. Analysis of variance demonstrated the stable performance of the envelopment–based approach in most cases. Additionally, it improved the morphology of the Green (G) channel, including changing trends and directions, adjusting wave sizes, reducing noise, and reinforcing details of the single waveform. The envelope–based linear model approach has the ability to flexibly improve RPPG signals, which helps RPPG play a full role in many fields such as medicine.
A Modular Algorithm Based on the Minimum-Cost-Path Problem for Optimizing LTC Operations in Photovoltaic Integrated Distribution Systems
Authors: Yaniv Arbel , Beck Yuval
Published: June 2023

This paper presents a novel modular voltage control algorithm for optimal scheduling of a distribution system’s load tap changers to minimize the number of tap changes while maintaining a voltage deviation (VD) around a desired target. To this end, a bi-objective optimal voltage regulation (OVR) problem is addressed in two distinct stages. First, the operational constraint on the load tap changer is removed to form a single-objective OVR problem relating to the voltage. The solution obtained in this stage is ultimately utilized to determine the penalty value assigned to the distance from the optimal (solely in terms of voltage) control value. In the second stage, the optimal scheduling problem is formulated as a minimum-cost-path problem, which can be efficiently solved via dynamic programming. This approach allows the identification of optimal scheduling that considers both the voltage-related objective as well as the number of load tap changer switching operations with no added computational burden beyond that of a simple voltage optimization problem. The method imposes no restriction on the load tap changer’s operation and is tested under two different target functions on the standard IEEE-123 test case. The first attains a nominal voltage with a 0.056 p.u. voltage deviation and the second is the well-known conservation voltage reduction (CVR) case with a 0.17 p.u. voltage deviation. The method is compared to an evolutionary-based algorithm and shows significant improvement in the voltage deviation by a factor of 3.5 as well as a computation time acceleration of two orders of magnitude. The paper demonstrates the effectiveness and potential of the proposed method as a key feature in future cutting-edge OVR methods.
Overview of Methods for Enhanced Oil Recovery from Conventional and Unconventional Reservoirs
Authors: Malozyomov Boris V. , Martyushev Nikita V. , Kukartsev Vladislav V. , Tynchenko Vadim S. , Bukhtoyarov Vladimir V. , Wu Xiaogang , Tyncheko Yadviga A. , Kukartsev Viktor A.
Published: June 2023

In world practice, the role of reproduction of raw material base of oil production by implementing modern methods of oil recovery enhancement (thermal, gas, chemical, microbiological) on the basis of innovative techniques and technologies is rapidly growing and is becoming more important. It is concluded that at present, the priority of increasing oil reserves in world oil production is the development and industrial introduction of modern integrated methods of enhanced oil recovery, which can provide a synergistic effect in the development of new and developed oil fields. This article presents a review and comparative analysis of theoretical and practical methods of improving oil recovery of conventional and unconventional reservoirs. The paper examines in detail methods of improving oil recovery, taking into account the factors of enhanced oil recovery of oil reservoirs. Considered the main methods and technologies currently used to develop oil fields and recommendations for their effective use, taking into account the variety of external factors of oil production: the geological structure of the reservoir, its volume, and properties of oils. It is shown that there is no universal method of oil reservoir development, and it must be chosen after a thorough feasibility study among several proposed models. When describing the methods of enhanced oil recovery, special attention is also paid to the physical processes that occur as a result of applying the technology. In conclusion, the positive and negative characteristics of the presented methods included in EOR are presented, and recommendations that may influence the choice of practical solutions for engineers and oil producers are given. Conclusions are made that development systems, placement and choice of operating mode of wells essentially depend on the geological structure of the reservoir, its volume and properties of oils. An important role in this is the construction of a geological model of the production facility. The used hydrodynamic models of development are based on physical laws, about which oil producers sometimes don’t even suspect, and the authors of the models are not always able to convey it to the real producers. The authors consider it reasonable to make a logical generalizing conclusion that understanding processes occurring in the reservoir and taking appropriate measures for optimization and intensification of oil production will allow making oil production as effective as possible.
Viable Recycling of Polystyrene via Hydrothermal Liquefaction and Pyrolysis
Authors: Musivand Sogand , Bracciale Maria Paola , Damizia Martina , De Filippis Paolo , de Caprariis Benedetta
Published: June 2023

Chemical recycling is considered one of the most sustainable solutions to limit the environmental issues related to plastic waste pollution, whereby plastic is converted into more valuable compounds when mechanical recycling is not feasible. Among the most critical fast-growing components of municipal solid waste, polystyrene represents 1/3 of the filling materials in landfills. In this work, the chemical recycling of polystyrene via two main thermochemical processes is investigated: pyrolysis and hydrothermal liquefaction (HTL). The influence of temperature (HTL: 300–360 °C and pyrolysis: 400–600 °C) and reaction time (HTL: 1–4 h; pyrolysis: 30 min) on the products obtained was studied. The obtained liquid and solid products were analyzed by using gas chromatography-mass spectrometry (GC-MS), an elemental analysis (EA), Fourier-transform infrared spectroscopy (FT-IR) and a thermogravimetric analysis (TGA). During HTL, a temperature of 360 °C and reaction time of 4 h were needed to completely decompose the polystyrene into mainly oil (83%) and water-soluble compounds (10%). The former was mainly composed of aromatics while the water phase was mainly composed of aromatics and oxygenated compounds (benzaldehyde and acetophenone). The pyrolysis led to the formation of 45% gas and 55% oil at 500 °C, and the oil was 40% styrene. Pyrolysis was thus more selective towards the recovery of the styrene monomer while the HTL can be an effective process to produce renewable aromatics.
Determination of Country-Specific Criteria Weights for Long-Term Energy Planning in Europe
Authors: Börcsök Endre , Groma Veronika , Gerse Ágnes , Osán János
Published: June 2023

Energy strategies and decision-making studies rely heavily on a system of criteria and their weights of importance, typically determined through stakeholder involvement or surveys. However, the methodology presented in this study considers a reverse approach, as the importance weights are computed based on historical data of each European country’s prevailing decisions on pre-defined aspects. An in-house-developed model was applied to analyze data from the ENTSO-E database for the determination of optimal criteria weights with combination of a linear programming task and Monte Carlo simulations. Applying the new model, the importance weights of seven selected criteria could be calculated for all European countries. The Eastern European region demonstrated exceptional sensitivity towards investment costs, while countries relying heavily on renewable or nuclear energy sources, such as Denmark, Greece, Norway, Slovenia, Spain, and the United Kingdom, exhibited a dominant influence of environmental factors. Moreover, it was observed that the flexibility criterion aligned well with the installed generation capacities. However, the geopolitical factor and the risk of accidents criteria introduced nuances to the overall rating, indicating a somewhat reduced dependence on production data.
Free and Wire-Guided Spark Discharges in Water: Pre-Breakdown Energy Losses and Generated Pressure Impulses
Authors: Chai Yifan , Timoshkin Igor V. , Wilson Mark P. , Given Martin J. , MacGregor Scott J.
Published: June 2023

Impulsive underwater discharges have been investigated for many decades, yet the complex pre-breakdown processes that underpin their development are not fully understood. Higher pre-breakdown energy losses may lead to significant reduction in the magnitude and intensity of the pressure waves generated by expanding post-breakdown plasma channels. Thus, it is important to characterize these losses for different discharge types and to identify approaches to their reduction. The present paper analyses thermal pre-breakdown processes in the case of free path and wire-guided discharges in water: fast joule heating of a small volume of water at the high-voltage electrode and joule heating and the melting of the wire, respectively. The energy required for joule heating of the water and metallic wire have been obtained from thermal models, analysed and compared with the experimental pre-breakdown energy losses. Pressure impulses generated by free path and by wire-guided underwater discharges have also been investigated. It was shown that wire-guided discharges support the formation of longer plasma channels better than free path underwater discharges for the same energy available per discharge. This results in stronger pressure impulses developed by underwater wire-guided discharges. It has been shown that the pressure magnitude in the case of both discharge types is inversely proportional to the observation distance which is a characteristic of a spherical acoustic wave.
Electrochemically Structured Copper Current Collectors for Application in Energy Conversion and Storage: A Review
Authors: Kurniawan Mario , Ivanov Svetlozar
Published: June 2023

Copper current collectors (Cu CCs) impact the production technology and performance of many electrochemical devices by their unique properties and reliable operation. The efficiency of the related processes and the operation of the electrochemical devices could be significantly improved by optimization of the Cu CCs. Metallic Cu plays an important role in electrochemical energy storage and electrocatalysis, primarily as a conducting substrate on which the chemical processes take place. Li nucleation and growth can be influenced by the current collector by modulating the local current density and Li ion transport. For example, the commonly used planar Cu CC does not perform satisfactorily; therefore, a high number of different modifications of Cu CCs have been proposed and reported in the literature for minimizing the local current density, hindering Li dendrite formation, and improving the Coulombic efficiency. Here, we provide an updated critical overview of the basic strategies of 3D Cu CC structuring, methodologies for analyzing these structures, and approaches for effective control over their most relevant properties. These methods are described in the context of their practical usefulness and applicability in an effort to aid in their easy implementation by research groups and private companies with established traditions in electrochemistry and plating technology. Furthermore, the current overview could be helpful for specialists with experience in associated fields of knowledge such as materials engineering and surface finishing, where electrochemical methods are frequently applied. Motivated by the importance of the final application of Cu CCs in energy storage devices, this review additionally discusses the relationship between CC properties and the functional parameters of the already-implemented electrodes.
Glycerol as an Anti-Knock Additive and Secondary Fuel as a Substitute for Gasoline-Based Fuels for the IC Engine
Authors: Szwaja Stanislaw , Gruca Michal , Pyrc Michal , Juknelevičius Romualdas
Published: June 2023

The article discusses the possibility of using glycerol as an additive to the engine fuel in order to reduce the tendency of combustion knock, and thus to increase the octane number of a given fuel. Experimental tests were carried out on the UIT-85 research engine with a variable compression ratio from eight to eleven to test the intensity of the knock. The completely renewable fuel—the blend of glycerol with butanol in the ratio of 25 and 75%, respectively—was tested. A comparative analysis of the knock intensity was conducted with gasoline 95 and N-butanol tested as reference fuels. The developed method for knock analysis using the proposed knock indicator was also presented. The experimental results proved the proposed blend of N-butanol and glycerol reduces the knock intensity by more than 50% in the spark-ignition engine at a compression ratio of 10, maintaining engine performance at a similar level as it was for a gasoline-fueled engine. The results confirmed the thesis on the reduction of knock intensity when adding glycerol to N-butanol.
Cycloadditions and Cyclization Reactions via Post-Synthetic Modification and/or One-Pot Methodologies for the Stabilization of Imine-Based Covalent Organic Frameworks
Authors: Gala Elena , Ramos M. Mar , Segura José L.
Published: June 2023

Interest in covalent organic frameworks as high-value materials has grown steadily since their development in the 2000s. However, the great advantage that allows us to obtain these crystalline materials—the reversibility of the bonds that form the network—supposes a drawback in terms of thermal and chemical stability. Among the different strategies employed for the stabilization of imine-based Covalent Organic Frameworks (COFs), cycloaddition and other related cyclization reactions are especially significant to obtain highly stable networks with extended π-delocalization and new functionalities, expanding even further the potential application of these materials. Therefore, this entry gathered the most recent research strategies for obtaining stable COFs by means of cyclization reactions, including the Povarov reaction and intramolecular oxidative cyclization reactions as well as some other recent innovative approaches.
A Review on Vibration Monitoring Techniques for Predictive Maintenance of Rotating Machinery
Authors: Romanssini Marcelo , de Aguirre Paulo César C. , Compassi-Severo Lucas , Girardi Alessandro G.
Published: June 2023

Machine failure in modern industry leads to lost production and reduced competitiveness. Maintenance costs represent between 15% and 60% of the manufacturing cost of the final product, and in heavy industry, these costs can be as high as 50% of the total production cost. Predictive maintenance is an efficient technique to avoid unexpected maintenance stops during production in industry. Vibration measurement is the main non-invasive method for locating and predicting faults in rotating machine components. This paper reviews the techniques and tools used to collect and analyze vibration data, as well as the methods used to interpret and diagnose faults in rotating machinery. The main steps of this technique are discussed, including data acquisition, data transmission, signal processing, and fault detection. Predictive maintenance through vibration analysis is a key strategy for cost reduction and a mandatory application in modern industry.
Yemen Advanced Field Epidemiology Training Program: An Impact Evaluation, 2021
Authors: Abduljalil Maeen , Al Kohlani Abdulhakeem , Jumaan Aisha , Al Serouri Abdulwahed
Published: June 2023

This is the first evaluation of the Yemen Field Epidemiology Training Program (Y-FETP) to assess if it met its objectives. We collected data using mixed methods including desk review, a focus group discussion with the Y-FETP staff, in-depth interviews with 21 program stakeholders, and an online survey for the program’s graduates. We transcribed/analyzed qualitative data using explanatory quotations and survey data using descriptive methods. The desk review indicated that Y-FETP covers 18 (82%) out of 22 governorates and conducted >171 outbreak investigations, 138 surveillance system analyses/evaluations, 53 planned studies, published >50 articles and had >155 accepted conference abstracts. Qualitative findings showed Y-FETP helped save lives and reduced morbidity/mortality using building capacities in outbreak response; provided evidence-based data for decision-making; and increased awareness about public health issues. An online survey showed that Y-FETP helped 60 to 80% of graduates conduct outbreak investigations, surveillance analysis/evaluation, manage surveillance systems/projects, engage in public health communication (reports/presentation), and use basic statistical methods. However, the evaluation revealed that Y-FETP is primarily funded by donors; thus, it is not sustainable. Other challenges include low graduate retention and limited training in policy development and management. Y-FETP achieved its main objectives of increasing the number of epidemiologists in the workforce, making a positive impact on public health outcomes.
Spatial Changes of Suburban Forest Ecological Functions and Their Impact on Ecological Equity in the Process of Urbanization—A Case Study of Jiangning District, Nanjing, China
Authors: Ren Fang , Chen Liuan , Li Tao , Li Mingyang
Published: June 2023

After the transformation of counties in urban suburbs into districts, the rapid urbanization and industrialization process in China’s developed regions had a huge impact on the spatial distribution and equity of the suburban forest ecological functions. Accurately describing this impact could provide an important reference for the construction of suburban forest engineering and for ecological environmental planning. Jiangning District of Nanjing City, China, was selected as the research area, while the forest resource planning and design survey data in 2007 and 2017, together with the demographic data of the study area, were collected as the main information sources. Following the establishment of the forest ecological function evaluation indicators and the analysis of the spatial change of the forest ecological functions, the Gini coefficient was calculated to analyze the changes of the regional ecological function equality. The results showed that: (1) Compared with 2007, the proportion of areas with low forest ecological functions (abbreviated as FEF) in the study area in 2017 showed a downward trend, and the proportion of areas with medium and high FEF showed an increasing trend; (2) Compared with 2007, the forest landscape in the study area in 2017 was severely fragmented, the spatial aggregation of the FEF showed a significant decline, and the FEF developed towards a direction of spatially balanced distribution; (3) During 2007–2017, the sub-compartments with high-value FEF in the study area (hot spots) shifted to the northwest, where the economy was developed and the population density was higher, and the sub-compartments with low-value (cold spots) shifted to the south, where the economy is underdeveloped and with lower population density; (4) From 2007 to 2017, the Gini coefficient of the FEF in the study area decreased, indicating that the regional ecological equity had initially improved. The urbanization and industrialization process of the urban suburbs is a double-edged sword. On the one hand, the process has caused the fragmentation of forest landscape, the decline of the forest area, and the unbalanced spatial distribution of the population. On the other hand, the huge material wealth and human capital accumulated through industrialization have promoted regional ecological equity and improved the living environment of the local residents.
Optimization of Main Ingredient Ratio, Metabolomics Analysis, and Antioxidant Activity Analysis of Lycopene-Enriched Compound Fruit Wine
Authors: Liu Kunyi , Liu Xiangyu , Wang Teng , Wang Qi , Feng Lei , Su Rui , Zhang Meng , Xu Bin , Chen Fei , Li Pingping
Published: June 2023

To find the optimal main ingredient ratio of compound fruit wine for enriching the varieties of lycopene-enriched fruit products and improving their economic value, fuzzy mathematics sensory evaluation and the D-optimal mixture design were considered. Under the main ingredient ratios of tomato juice, papaya juice, carrot juice, and gac fruit juice of 27.2%, 27.5%, 10.0%, and 35.3%, respectively, a clear and transparent compound fruit wine with a full-bodied fruit and wine aroma and mellow taste can be obtained. Meanwhile, a total of 406 metabolites were identified in the compound fruit wine, which were classified into nine superclasses including lipids and lipid-like molecules (150), organic acids and derivatives (69), and others. The relative levels of 54 metabolites after optimization were decreased significantly (VIP > 1.0, p < 0.05, FC < 0.5), while the relative levels of 106 metabolites including lycopene and (13Z)-lycopene were increased significantly (VIP > 1.0, p < 0.05, FC > 2). Furthermore, the EC50 values of this compound fruit wine after optimization of the main ingredient ratio for scavenging ABTS+·, DPPH·, O2−·, and ·OH were 78.62%, 57.74%, 42.85%, and 59.91%, respectively. Together, a compound fruit wine rich in lycopene with antioxidant activities was manufactured, which has application potential in the development of functional foods.
Numerical Study of Efficient Tm-Doped Zinc-Tellurite Fiber Lasers at 2300 nm
Authors: Anashkina Elena , Andrianov Alexey
Published: June 2023

Fiber laser sources operating near 2300 nm in the atmospheric transparency window are interesting for different applications, such as remote sensing, lidars, and others. The use of Tm-doped fiber lasers based on tellurite fibers is highly promising. We propose and theoretically study a highly efficient diode-pumped Tm-doped zinc-tellurite fiber laser operating at two cascade radiative transitions at 1960 nm and 2300 nm, with additional energy transfer between these laser waves due to the Raman interaction. We demonstrate numerically that a dramatic increase in the slope efficiency up to 57% for the laser wave at 2300 nm, exceeding the Stokes limit by 22% relative to the pump at 793 nm, can be obtained with optimized parameters thanks to Raman energy transfer from the laser wave at 1960 nm to the wave at 2300 nm.
Not Just a Banana: The Extent of Fruit Cross-Reactivity and Reaction Severity in Adults with Banana Allergy
Authors: Julanon Narachai , Thiravetyan Ben , Unhapipatpong Chanita , Xanthavanij Nutchapon , Krikeerati Thanachit , Thongngarm Torpong , Wongsa Chamard , Songnuan Wisuwat , Naiyanetr Phornnop , Sompornrattanaphan Mongkhon
Published: June 2023

This cross-sectional study aimed to investigate the prevalence and clinical characteristics of cross-reactivity and co-allergy to other plant foods among adult patients with IgE-mediated banana allergy in Thailand. A structured questionnaire was used to assess clinical reactivity, and cross-reactivity diagnoses were based on reactions occurring within 2 years of banana allergy onset, within 3 h of intake, and confirmed by allergists. Among the 133 participants, the most commonly associated plant foods with clinical reactions were kiwi (83.5%), avocado (71.1%), persimmon (58.8%), grapes (44.0%), and durian (43.6%). Notably, 26.5% of the reported reactions to other plant foods were classified as severe. These findings highlight the common occurrence of cross-reactivity/co-allergy to other plant foods in banana-allergic patients, with a significant proportion experiencing severe reactions. Travelers to tropical regions should be aware of this risk and advised to avoid specific banana cultivars and plant foods with reported high cross-reactivity. The inclusion of self-injectable epinephrine in the management plan for patients with primary banana allergy should be considered due to the substantial proportion of reported severe reactions and the wide range of clinical cross-reactivity and co-allergy observed.
Introduction to the Special Issue: Preparation, Physicochemical Properties and Application of Natural Plant Polysaccharides
Authors: Niu Yuge
Published: June 2023

As natural products, plant polysaccharides have been demonstrated to induce a variety of biological activities by numerous epidemiological investigations and interventional studies, including immunomodulation and antioxidant, antibacterial, antitumor, hypolipidemic, hypoglycemic processes, etc [...]