bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Temperature-Sensing Performance of Photonic Crystal Fiber via External Metal-Coated Trapezoidal-Shaped Surface
Authors: Chao Chung-Ting Chou , Chen Sy-Hann , Huang Hung Ji , Kooh Muhammad Raziq Rahimi , Lim Chee Ming , Thotagamuge Roshan , Mahadi Abdul Hanif , Chau Yuan-Fong Chou
Published: May 2023

This article describes a photonic crystal fiber (PCF) temperature sensor that utilizes a flat, metal-coated trapezoidal surface. The PCF is made up of two layers of elliptical air holes and a polished trapezoidal surface that allows temperature sensing. An external sensing approach is used to deposit a thin silver layer on the reflective surface, while a thin SiO2 film acts as an oxidation-resistant coating. The top elliptical air hole serves as the interface for energy transformation from the core-guided mode to the surface plasmon-polariton (SPP) mode. Simulations carried out using the finite element method indicate that the proposed SPR-PCF temperature sensor can achieve a maximum temperature sensitivity and resolution of up to 5200 pm/°C and 0.01923 °C, respectively, across a temperature range of 10 to 60 °C. This research has significant potential for sensor design and real-time temperature remote sensing applications.
Normally-Off p-GaN Gate High-Electron-Mobility Transistors with the Air-Bridge Source-Connection Fabricated Using the Direct Laser Writing Grayscale Photolithography Technology
Authors: Zhang Yujian , Ding Guojian , Wang Fangzhou , Yu Ping , Feng Qi , Yu Cheng , He Junxian , Wang Xiaohui , Xu Wenjun , He Miao , Wang Yang , Chen Wanjun , Jia Haiqiang , Chen Hong
Published: May 2023

In this work, we used the Direct Laser Writing Grayscale Photolithography technology to fabricate a normally-off p-GaN gate high-electron-mobility transistor with the air-bridge source-connection. The air-bridge source-connection was formed using the Direct Laser Writing Grayscale Photolithography, and it directly connected the two adjacent sources and spanned the gate and drain of the multi-finger p-GaN gate device, which featured the advantages of stable self-support and large-span capabilities. Verified by the experiments, the fabricated air-bridge p-GaN gate devices utilizing the Direct Laser Writing Grayscale Photolithography presented an on-resistance of 36 Ω∙mm, a threshold voltage of 1.8 V, a maximum drain current of 240 mA/mm, and a breakdown voltage of 715 V. The results provide beneficial design guidance for realizing large gate-width p-GaN gate high-electron-mobility transistor devices.
Microstructural Evolution and Deformation Behavior of a Solution-Treated Ti-Al-Mo-Fe Metastable Beta Titanium Alloy during Room-Temperature Deformation
Authors: Tang Wei , Zhang Xiaobin , Yu Chuankui , Wu Linlang , Zhang Han , Li Chenglin
Published: May 2023

Beta titanium (β-Ti) alloys have been widely used in aerospace and biomedical implants due to their specific strengths, low elastic modulus, and their resistance to corrosion. As β titanium alloy is a novel metastable, Ti-2Al-9.2Mo-2Fe (wt.%) alloy is essential to understand microstructural evolution and deformation behavior at room temperature to improve the strength–ductility balance. The deformation behavior and microstructural evolution of the Ti-2Al-9.2Mo-2Fe alloy during room-temperature deformation has been investigated via electron backscatter diffraction (EBSD) and electron channeling contrast imaging (ECCI). It was found that the β-solution-treated alloy exhibited a single β phase with a lower β stability. However, the α/β-solution-treated alloy exhibited a layered structure, consisting of fine α + β grain layers and coarse β grain layers, and the β in the coarse grain layer had a lower stability, but the β in the fine grain layer had a higher stability owing to the coexistence of α. The β-solution-treated alloy was mainly deformed via {332}<113> deformation twinning, thus showing very high ductility; uniform elongation of approximately 35%. The α/β-solution-treated alloy was deformed via two mechanisms, namely {332}<113> deformation twinning in the coarse grain layers and dislocation slip in the fine grain layers. The α/β-solution-treated alloy exhibited high strength with a lower ductility due to the small amount of deformation twinning.
Three New Species of Jainus (Monogenea: Dactylogyridae) Parasitizing Gills of Brazilian Freshwater Fishes Supported by Morphological and Molecular Data
Authors: Yamada Priscilla de Oliveira Fadel , Müller Maria Isabel , Zago Aline Cristina , Yamada Fabio Hideki , Ebert Mariana Bertholdi , Franceschini Lidiane , da Silva Reinaldo José
Published: May 2023

The present study describes three new species of monogeneans parasitizing the gills of anostomid fishes from the Upper Paraná River basin, southeastern Brazil: Jainus beccus n. sp. and Jainus radixelongatus n. sp. on Leporinus friderici, Leporinus octofasciatus, Leporinus striatus, and Megaleporinus elongatus; and Jainus ornatus n. sp. on L. friderici. The new species differ from other congeners by the morphology of the accessory piece. There is a semicircular distal portion resembling a “bird’s beak” in Jainus beccus n. sp. It composed of two subunits—one ventral and more sclerotized, sickle-shaped, and another dorsal with three projections—in Jainus radixelongatus n. sp. There are two elongated and sclerotized subunits, both of which have a sickle-shaped distal portion, in Jainus ornatus n. sp. Supplementary observations not reported in the original descriptions of the type-species Jainus piava Karling, Bellay, Takemoto & Pavanelli, 2011 are proposed, as follows: the presence of a thin and delicate ventral bar, which can vary greatly in shape; an accessory piece not articulated with the MCO’s base. This paper provides the first phylogenetic study based on LSU rDNA and COI mtDNA gene sequences for Jainus, improving and clarifying the understanding of host–parasite relationships in neotropical characiforms.
Conservation Genetic Analysis of Blanding’s Turtles across Ohio, Indiana, and Michigan
Authors: Guinto Daniel , Cross Matthew , Lipps Gregory , Lee Yuman , Kingsbury Bruce , Earl Daniel , Dempsey Connor , Hinson Jessica , Jordan Mark
Published: May 2023

The Blanding’s Turtle (Emydoidea blandingii) is a species in need of conservation across much of its geographic range. A key aspect to conserving a species is understanding the genetic diversity and population structure across the landscape. Several researchers have focused on E. blandingii genetic diversity in the northeastern United States, Canada, and parts of the Midwestern United States; however, little investigation has been carried out on localities within the Great Lakes region of Indiana, Michigan, and Ohio. Understanding genetic trends within this region will assist with conservation planning by documenting levels of genetic variation within and among localities and developing hypotheses that have led to the observed patterns. We used 14 microsatellite loci to characterize the genetic diversity of E. blandingii in 16 localities in Indiana, Ohio, and southeast Michigan (with one northwestern locality). Overall, genetic diversity within localities tended to be high and little differentiation was observed among sample localities. No consistent evidence of bottlenecks was detected, and effective population size (Ne) estimates were generally high, but likely biased by sample size. A minimum of two clusters, and as many as seven clusters in a hierarchical analysis, were identified using three methods for grouping individuals (STRUCTURE, TESS3r, and sPCA). A correlation between geographic distance and genetic differentiation (isolation by distance) was observed. The long lifespan and historic gene flow of E. blandingii is likely responsible for the observed genetic diversity and lack of differentiation between localities. This should not suggest that populations are secure in the Great Lakes Region. Modeling aimed at estimating future genetic variation in populations under realistic demographic scenarios indicates that many localities in the region are likely to be vulnerable to genetic loss in the next 200 years.
Hemodynamic Performance of Transcatheter Aortic Valves: A Comprehensive Review
Authors: Angellotti Domenico , Manzo Rachele , Castiello Domenico Simone , Immobile Molaro Maddalena , Mariani Andrea , Iapicca Cristina , Nappa Dalila , Simonetti Fiorenzo , Avvedimento Marisa , Leone Attilio , Canonico Mario Enrico , Spaccarotella Carmen Anna Maria , Franzone Anna , Ilardi Federica , Esposito Giovanni , Piccolo Raffaele
Published: May 2023

Transcatheter aortic valve implantation (TAVI) is a widely adopted treatment option for patients with severe aortic stenosis. Its popularity has grown significantly in recent years due to advancements in technology and imaging. As TAVI use is increasingly expanded to younger patients, the need for long-term assessment and durability becomes paramount. This review aims to provide an overview of the diagnostic tools to evaluate the hemodynamic performance of aortic prosthesis, with a special focus on the comparison between transcatheter and surgical aortic valves and between self-expandable and balloon-expandable valves. Moreover, the discussion will encompass how cardiovascular imaging can effectively detect long-term structural valve deterioration.
Automatic Diagnosis of Glaucoma from Retinal Images Using Deep Learning Approach
Authors: Shoukat Ayesha , Akbar Shahzad , Hassan Syed Ale , Iqbal Sajid , Mehmood Abid , Ilyas Qazi Mudassar
Published: May 2023

Glaucoma is characterized by increased intraocular pressure and damage to the optic nerve, which may result in irreversible blindness. The drastic effects of this disease can be avoided if it is detected at an early stage. However, the condition is frequently detected at an advanced stage in the elderly population. Therefore, early-stage detection may save patients from irreversible vision loss. The manual assessment of glaucoma by ophthalmologists includes various skill-oriented, costly, and time-consuming methods. Several techniques are in experimental stages to detect early-stage glaucoma, but a definite diagnostic technique remains elusive. We present an automatic method based on deep learning that can detect early-stage glaucoma with very high accuracy. The detection technique involves the identification of patterns from the retinal images that are often overlooked by clinicians. The proposed approach uses the gray channels of fundus images and applies the data augmentation technique to create a large dataset of versatile fundus images to train the convolutional neural network model. Using the ResNet-50 architecture, the proposed approach achieved excellent results for detecting glaucoma on the G1020, RIM-ONE, ORIGA, and DRISHTI-GS datasets. We obtained a detection accuracy of 98.48%, a sensitivity of 99.30%, a specificity of 96.52%, an AUC of 97%, and an F1-score of 98% by using the proposed model on the G1020 dataset. The proposed model may help clinicians to diagnose early-stage glaucoma with very high accuracy for timely interventions.
Cathepsin S Upregulation Measured in the Peripheral Blood Mononuclear Cells Prior to Surgery Points to Postoperative Pain Development in Patients with Hip Osteoarthritis
Authors: Tchetina Elena , Glemba Kseniya , Yunitskaya Anna , Markova Galina , Makarov Maksim , Lila Aleksandr
Published: May 2023

Disability caused by hip osteoarthritis has increased due to population aging, obesity, and lifestyle behaviors. Joint failure after conservative therapies results in total hip replacement, which is considered to be one of the most successful interventions. However, some patients experience long-term postoperative pain. Presently, there are no reliable clinical biomarkers for the prognosis of postoperative pain prior to surgery. Molecular biomarkers can be considered as intrinsic indicators of pathological processes and as links between clinical status and disease pathology, while recent innovative and sensitive approaches such as RT-PCR have extended the prognostic value of clinical traits. In light of this, we examined the importance of cathepsin S and proinflammatory cytokine gene expression in peripheral blood in addition to the clinical traits of patients with end-stage hip osteoarthritis (HOA) to predict postoperative pain development prior to surgery. This study included 31 patients with radiographic Kellgren and Lawrence grade III–IV HOA who underwent total hip arthroplasty (THA) and 26 healthy volunteers. Before surgery, a visual analog scale (VAS), DN4, PainDETECT, and the Western Ontario and McMaster Universities osteoarthritis index scores were used for pain and function assessment. Three and six months post-surgery, VAS pain scores of 30 mm and higher were reported. The intracellular protein levels of cathepsin S were measured using ELISA. The expression of the cathepsin S, tumor necrosis factor α, interleukin-1β, and cyclooxygenase-2 genes in peripheral blood mononuclear cells (PBMCs) was assessed using quantitative real-time RT-PCR. Pain persisted in 12 (38.7%) patients after THA. Patients who developed postoperative pain demonstrated significantly higher cathepsin S gene expression in the PBMCs and higher rates of neuropathic pain based on the DN4 testing compared to the other HOA subjects that were examined. No significant differences in proinflammatory cytokine gene expression were noted in either patient cohort prior to THA. The development of postoperative pain in patients with hip osteoarthritis might be associated with disturbances in pain perception, while increased expression of cathepsin S in the peripheral blood prior to surgery may serve as its prognostic biomarker and could be used in clinical settings to improve medical service for patients with end-stage hip OA.
Remaining Useful Life Prediction of Rolling Bearings Based on Multi-Scale Attention Residual Network
Authors: Song Lin , Wu Jun , Wang Liping , Chen Guo , Shi Yile , Liu Zhigui
Published: May 2023

The remaining useful life (RUL) prediction of rolling bearings based on vibration signals has attracted widespread attention. It is not satisfactory to adopt information theory (such as information entropy) to realize RUL prediction for complex vibration signals. Recent research has used more deep learning methods based on the automatic extraction of feature information to replace traditional methods (such as information theory or signal processing) to obtain higher prediction accuracy. Convolutional neural networks (CNNs) based on multi-scale information extraction have demonstrated promising effectiveness. However, the existing multi-scale methods significantly increase the number of model parameters and lack efficient learning mechanisms to distinguish the importance of different scale information. To deal with the issue, the authors of this paper developed a novel feature reuse multi-scale attention residual network (FRMARNet) for the RUL prediction of rolling bearings. Firstly, a cross-channel maximum pooling layer was designed to automatically select the more important information. Secondly, a lightweight feature reuse multi-scale attention unit was developed to extract the multi-scale degradation information in the vibration signals and recalibrate the multi-scale information. Then, end-to-end mapping between the vibration signal and the RUL was established. Finally, extensive experiments were used to demonstrate that the proposed FRMARNet model can improve prediction accuracy while reducing the number of model parameters, and it outperformed other state-of-the-art methods.
Recommending Words Using a Bayesian Network
Authors: Santos Pedro , Pato Matilde , Datia Nuno , Sobral José , Leitão Noel , Ramos Ferreira Manuel , Gomes Nuno
Published: May 2023

Asset management involves the coordinated activities of an organisation to derive value from assets, which may include physical assets. It encompasses activities related to design, construction, installation, operation, maintenance, renewal, and asset disposal. Asset management ensures the coordination of all activities, resources, and data related to physical assets. Recording and monitoring all maintenance activities is a key part of asset management, often done using work orders (WOs). Technicians typically create WOs using “free text”, which can result in missing or ungrammatical words, making it difficult to identify trends and analyse information. To standardise the terminology used for the same asset maintenance operation, this paper proposes a method that suggests words to technicians as they complete WOs. The word suggestion algorithm is based on past maintenance records, and a Bayesian network-based recommender system adapts to present needs verified by technicians using implicit user feedback. Implementing this system aims to normalise the terms used by technicians when filling in a WO. The corpus for this work comes from asset management records collected in a health facility in Portugal operated by a private company.
Self-Organized Aggregation Behavior Based on Virtual Expectation of Individuals with Wave-Based Communication
Authors: Gia Luan Phan , Truong Thinh Nguyen
Published: May 2023

In this study, a microscopic model for a swarm of mobile robots is developed to implement self-organized aggregation behavior. The proposed model relies on the concept of subjective expectation, which is defined as the “minimum wished cluster size” of a robot in the swarm. During the whole process, a robot’s expectation constantly changes based on context awareness. This awareness is obtained by employing a low-cost communication system commonly found in swarm robot studies: infrared-based communication. Robots can make their own decisions by comparing their expected and estimated observed cluster sizes, which leads to macroscopic swarm aggregation. However, due to the limitations of local communication and mobility, robots are restricted in their ability to perceive global information, particularly regarding cluster size. Inspired by the slime mold aggregation process, a wave-based communication mechanism is implemented to help robots estimate a cluster size. Moreover, each transmission includes a modulated message that allows robots to explicitly share their knowledge with others. In this way, despite the fact that the robot may not belong to that cluster due to its perception range, it can easily grasp the cluster size when passing the cluster. Once a robot detects a desired cluster, it can approach this cluster with its direction determined by using average origin of wave (AOW) method. The performance of the aggregation algorithm was tested both in simulation and with a real swarm robot. Dispersion metrics and cluster metrics were employed to evaluate the proposed algorithm’s performance. The results show that the proposed microscopic model utilizes collective behavior which aggregates all randomly distributed robots into a single aggregate cluster with a reasonable swarm density and evaluation time.
Development and Testing of a Miniaturized Platform for Photoplethysmography
Authors: Traversi Gianluca , Gaioni Luigi , Salvetti Davide
Published: May 2023

This paper presents the design and characterization of a miniaturized wearable electronic system for photoplethysmography. The system is conceived with the purpose of monitoring people during their normal duties or during physical activity. An in-depth investigation of its performance has been carried out to address the main parameters affecting signal quality. Moreover, an investigation of the best body measurement location has been assessed.
A THz Slot Antenna Design Using Analytical Techniques
Authors: Rozenberg Shay , Yahalom Asher
Published: May 2023

Slot antennas are very popular microwave antennas, and slotted waveguides are used for high frequency radar systems. A thin slot in an infinite ground plane is the complement to a dipole in free space. This was described by H.G. Booker, who extended Babinet’s principle from optics to show that the slot will have the same radiation pattern as a dipole such that the E and H fields are swapped. As a result, the polarization is rotated, so that radiation from the vertical slot is polarized horizontally. In this work, we show how this straightforward analytical technique can be used for the design of high-frequency THz slot antennas. The analysis is then corroborated by using a numerical simulation which validates the performance parameters predicted by the analytical technique. We show by simulation that, despite the simplicity of our classical approach, we obtained useful results, even at THz frequencies. We show that gradually moving the slot position from the centerline improves the antenna’s performance.
Vision-Based Support for the Detection and Recognition of Drones with Small Radar Cross Sections
Authors: Abdelsamad Safa E. , Abdelteef Mohammed A. , Elsheikh Othman Y. , Ali Yomna A. , Elsonni Tarik , Abdelhaq Maha , Alsaqour Raed , Saeed Rashid A.
Published: May 2023

Drones are increasingly vital in numerous fields, such as commerce, delivery services, and military operations. Therefore, it is essential to develop advanced systems for detecting and recognizing drones to ensure the safety and security of airspace. This paper aimed to develop a robust solution for detecting and recognizing drones and birds in airspace by combining a radar system and a visual imaging system, and contributed to this effort by demonstrating the potential of combining the two systems for drone detection and recognition. The results showed that this approach was highly effective, with a high overall precision and accuracy of 88.82% and 71.43%, respectively, and the high F1 score of 76.27% indicates that the proposed combination approach has great effectiveness in the performance. The outcome of this study has significant practical implications for developing more advanced and effective drone and bird detection systems. The proposed algorithm is benchmarked with other related works, which show acceptable performance compared with other counterparts.
A Distance Vector Hop-Based Secure and Robust Localization Algorithm for Wireless Sensor Networks
Authors: Asif Rameez , Farooq-i-Azam Muhammad , Chaudary Muhammad Hasanain , Husen Arif , Hassan Syed Raheel
Published: May 2023

Location information of sensor nodes in a wireless sensor network is important. The sensor nodes are usually required to ascertain their positions so that the data collected by these nodes can be labeled with this information. On the other hand, certain attacks on wireless sensor networks lead to the incorrect estimation of sensor node positions. In such situations, when the location information is not correct, the data may be labeled with wrong location information that may subvert the desired operation of the wireless sensor network. In this work, we formulate and propose a distance vector hop-based algorithm to provide secure and robust localization in the presence of malicious sensor nodes that result in incorrect position estimation and jeopardize the wireless sensor network operation. The algorithm uses cryptography to ensure secure and robust operation in the presence of adversaries in the sensor network. As a result of the countermeasures, the attacks are neutralized and the sensor nodes are able to estimate their positions as desired. Our secure localization algorithm provides a defense against various types of security attacks, such as selective forwarding, wormhole, Sybil, tampering, and traffic replay, compared with other algorithms which provide security against only one or two types. Simulation experiments are performed to evaluate the performance of the proposed method, and the results indicate that our secure localization algorithm achieves the design objectives successfully. Performance of the proposed method is also compared with the performance of basic distance vector hop algorithm and two secure algorithms based on distance vector hop localization. The results reveal that our proposed secure localization algorithm outperforms the compared algorithms in the presence of multiple attacks by malicious nodes.
Pre-Sizing Approach of a Fuel Cell-Battery Hybrid Power System with Interleaved Converters
Authors: Mercier Victor , Ceschia Adriano , Azib Toufik , Larouci Cherif
Published: May 2023

This paper proposes a design methodology that is dedicated to improving the concept of a modular hybrid power chain that uses interleaved converters. The approach involves optimising the system under multi-physical constraints, where the number of cells in the interleaved converters is considered as a key modular parameter. The methodology uses analytical models to strike a balance between computation time and result accuracy. This compromise is indispensable to the construction of a smart design approach under multi-physical constraints, such as electric, efficiency, volume, and thermal constraints. The proposed approach has been applied to a hybrid fuel cell and battery power system for automotive applications; the goal is to obtain a global optimal architecture chain by optimising the number of interleaved converter cells and by determining appropriate power electronics components and the optimal sizing of sources. This constitutes the primary step for providing an effective pre-design support tool for considering architecture modularity, facilitating the use of new technologies in the early design stage. The results showed that the interleaving concept allows for better flexibility in respecting the design constraints to improve the design of hybrid power systems. The analysis also highlights the current limitations and performance of the optimisation method and suggests new areas for future work.
A Three-Dimensional Simulation Model for Proton Exchange Membrane Fuel Cells with Conventional and Bimetallic Catalyst Layers
Authors: Tzelepis Stefanos , Kavadias Kosmas A. , Marnellos George E.
Published: May 2023

A three-dimensional steady-state model has been developed to study the phenomena that occurs during Proton Exchange Membrane Fuel Cell’s (PEMFC) operation. Electrochemical and transport phenomena on both the anode and cathode sides were investigated. Particular emphasis has been given to the composition and structure of the catalyst layers (CLs), considering parameters such as the metal loading, the most effective specific metal surface, the agglomeration, and the particle size. In this context, two types of CLs were investigated. The first type concerns conventional CLs consisting of Pt/C, while the second type refers to bimetallic CLs consisting of Pt-Ru/C. In both cases, the CLs were examined for various loadings of Pt, Ru, and C to define the optimum atomic ratio for an enhanced PEMFC performance, while, in parallel, possible challenges are intedified. The mathematical model for simulating the entire phenomena and the method for modeling the bimetallic catalyst layers are presented. The results show a good agreement between the model and the experimental data reported in the literature. Additionally, the scenario of bimetallic CLs consisting of Pt-Ru/C with a ratio of 50-50 (Pt-Ru) significantly improved the overall PEMFC electrochemical performance.
Resilience Appraisal of Water Resources System under Climate Change Influence Using a Probabilistic-Nonstationary Approach
Authors: Waheed Saddam Q. , Alobaidy Maryam N. , Grigg Neil S.
Published: May 2023

The planning and management of water resources are being impacted by climate change, and are in need of comprehensive adaptation strategies to respond to future projections. The goal of this study is to support those strategies with a new decision-making paradigm that employs a probabilistic-nonstationary hydroclimatic scenario to examine the long-term system resilience for multiple dam objectives. The modified approach to examine resilience was applied, and uses a bottom-up approach with a modified resilience concept to achieve the long-term operation targets. The approach integrates Global Circulation Models (GCMs) with a statistical weather generator (SWG) to produce a range of future scenarios. Then, the system response is evaluated against those scenarios. The study utilizes a pre-developed SWG to synthesize different trajectories by altering three weather variables: the precipitation amount, temperature mean, and wind-speed magnitude. The proposed has four staged phases: (1) identification of the future climate exposure using different GCMs; (2) future water supply estimation for scenarios using hydrological models; (3) future water demand estimation for scenarios of all system stakeholders; and (4) evaluation of system performance resilience for the dam operational purposes. The Diyala River Basin in Iraq was selected as a case study, to apply the suggested paradigm. The analysis of the GCM outputs revealed that the rainfall mean varies between −37% and +31%; temperature mean varies between +0.4 °C and 5.1 °C; and the mean wind speed varies between −22% and 11%. Based on these ranges, the future climate trajectories were simulated. According to the examination of the system’s response to those weather changes, the precipitation is the most effective parameter, followed by the temperature change, and lastly the wind speed. Furthermore, the findings show that the existing system operating rules are reliable in terms of flood protection but vulnerable in terms of drought management. The analysis of system resilience to manage the drought was found to be 0.74 for the future trajectories, while it was 0.91 for flood protection. This indicates that project managers should prioritize the drought and water scarcity management, due to climate change impact and upstream country development. The study also shows that the suggested resilience paradigm is capable of measuring the negative effects of climate change and able to provide long-term adaptation guidance for water resources management.
Selected Mechanical and Physical Properties of Thermally Modified Wood after Field Exposure Tests
Authors: Dong Huijun , Hasanagić Redžo , Fathi Leila , Bahmani Mohsen , Kržišnik Davor , Keržič Eli , Humar Miha
Published: May 2023

This study aimed to evaluate the impact of thermal modification on the physical and mechanical properties of three different wood species from Bosnia and Herzegovina, namely beech wood (Fagus sylvatica L.), linden wood (Tilia cordata), and silver fir wood (Abies alba). The samples underwent thermal modification at five different temperatures (170 °C, 180 °C, 195 °C, 210 °C, and 220 °C) for varying durations (ranging from 78 to 276 min). After treatment, they were exposed to outdoor conditions for twelve months. The study examined the four-point bending strength, tensile force, color change, and surface quality of the modified and unmodified samples. The results showed that outdoor exposure negatively impacted the mechanical properties of the unmodified samples, especially in the linden wood which was 41% and the beech wood which was 42%. Additionally, outdoor exposure caused significant surface cracks in the thermally modified linden and beech wood. The study also found prominent color changes in the modified and unmodified samples during twelve months of exposure. The roughness of the samples was determined with a confocal laser scanning microscope, which showed that the roughness increased on both the axial and the longitudinal surfaces after weathering. The highest roughness for the fir wood was determined to be 15.6 µm. Overall, this study demonstrates the importance of wood modification and its impact on the use-value of wood products.
Geographic Range vs. Occurrence Records in Plant Distribution Mapping: The Case of Arbutus in the Old World
Authors: De Santis Simone , Spada Francesco , Magri Donatella
Published: May 2023

Species mapping methods play a central role in biogeographical questions, as they may generate a domino effect on further works based on species distribution. In light of the massive recent increase in the availability of online occurrence data, we highlight the strengths and limitations of the mapping methods most widely used to display the geographic distribution of plants, namely geographic range maps and occurrence record maps. We use the modern distribution of the genus Arbutus in western Eurasia, North Africa, and Macaronesia, for which no occurrence record map has been published yet, to discuss critical issues in data collection and representation. The occurrence record map of A. unedo, A. andrachne, A. canariensis, and A. pavarii shows how well this mapping method captures the details of peripheral and isolated stands as well as the variability of population density. A number of biogeographical issues are addressed by this approach, including the determination of the chorological centre of gravity in relation to historical dynamics, genetic patterns in relation to range porosity, and the autochthony status of marginal stands. These issues constitute the necessary foundation for additional palaeobotanical research and ecological modelling to investigate the past-to-future dynamics of Arbutus and other species of the Mediterranean–Atlantic area.
Quality of the Pellets Obtained with Wood and Cutting Residues of Stone Pine (Pinus pinea L.)
Authors: Fernández Manuel , Tapias Raúl , Camacho Victoriano , Alaejos Joaquín
Published: May 2023

The use of wood and residual biomass from forestry works is a CO2 emission-neutral source of energy that also contributes to reducing the risk of spreading forest fires, especially under Mediterranean climate. The forest stands of stone pine (Pinus pinea L.) occupies about 0.7 million hectares in the Mediterranean basin. In this study, the commercial quality of the pellets manufactured from different types of cutting residues (needles and thin branches, medium branches and bark), as well as wood from trunks and thick branches, was assessed. It was concluded that with the exclusive use of residual biomass it is not possible to obtain pellets of high commercial quality, useful for residential or industrial use. However, the highest quality pellets could be obtained by combining them with stone pine debarked wood, but in a certain proportion that differs depending on the type of residue (around 15% for bark, 30% for medium branches and less than 15% for needles and thin branches). It is recommended to take advantage of both the thick wood (trunk + thick branches) and a proportion of medium branches and bark, while in the case of needles and thinnest branches it would be more convenient to leave them in the forest for their incorporation into the soil, given their high nutrients concentration and their low quality for energetic use. The results found support a greater valorization of the biomass obtained in the stone pine fellings. In the future it will be necessary to study which is the most appropriate logistics of the silvicultural works to be able to conveniently apply the results of this study.
Canopy Phenology and Meteorology Shape the Seasonal Dynamics in Hydrological Fluxes of Dissolved Organic Carbon in an Evergreen Broadleaved Subtropical Forest in Central Japan
Authors: Chen Siyu , Cao Ruoming , Yoshitake Shinpei , Ohtsuka Toshiyuki
Published: May 2023

Seasonal variabilities in hydrological fluxes of dissolved organic carbon (DOC) and their driving factors in the evergreen broad-leaved forest are inadequately understood. To aid this understanding, we conducted a three-year study to examine seasonal changes in DOC concentration and flux in throughfall, stemflow, and litter leachate in an evergreen broad-leaved subtropical forest in central Japan. We specifically addressed (1) how DOC in different hydrological fluxes vary on a monthly to seasonal basis, and (2) how canopy phenology and meteorology shape the DOC concentration and flux of throughfall, stemflow, and litter leachate trends in this evergreen forest. Clear seasonal changes were found in throughfall and stemflow DOC concentration but not in litter leachate DOC concentration; the highest throughfall DOC concentrations were observed in spring (10.03 mg L−1 in 2017 and 9.59 mg L−1 in 2018, respectively) and the highest stemflow DOC concentrations were observed in summer (13.95 mg L−1 in 2017 and 16.50 mg L−1 in 2018, respectively). Correlation analysis revealed the monthly throughfall DOC concentration to be positively related to the dry weight of fallen leaves (r = 0.72, p < 0.05) and flowers (r = 0.91, p < 0.05). In addition, Random Forest models predicted that the dry weight of flowers was a primary driver of throughfall DOC concentration and that the DOC concentrations of stemflow and litter leachate were constrained by the throughfall DOC concentration. DOC fluxes in different hydrological flux were significantly positive related to bulk precipitation amounts and temperature. Moreover, the throughfall DOC concentration had a considerable effect on throughfall and litter leachate DOC fluxes. Over 75% of annual net tree-DOC (throughfall + stemflow) fluxes and more than 70% of the annual litter leachate DOC fluxes were produced in the flowering season. Thus, we speculated that the seasonal phenological canopy changes (leaf emergence, fallen leaves, flowering, and pollen) and the sufficient rainfall had great impacts on the amount and quality of DOC concentrations in the evergreen forest; and, furthermore, that the DOC from different forest hydrological fluxes was a significant fraction of the carbon that accumulates in soils.
Genome-Wide Identification of the Argonaute Protein Family and Its Expression Analysis under PEG6000, ABA and Heat Treatments in Populus alba × P. glandulosa
Authors: Li Hongying , Wang Zhengbo , Gao Yanwu , Chen Mengdi , Hao Ziyuan , Chen Xi , Guo Lili , Fan Chunjie , Zhao Shutang
Published: May 2023

The argonaute (AGO) protein, as an important member of the small RNA (sRNA) regulatory pathway gene-silencing complex (RNA-induced silencing complex, RISC), is a key protein that mediates gene silencing and plays a key role in the recruitment of sRNAs. In this study, bioinformatics was used to identify the AGO gene family in poplar and study its expression in various tissues and in response to abiotic stress treatments. A total of 15 PtAGO genes were identified in poplar, which were unevenly distributed in 9 chromosomes. Most proteins were predicted to be located in the nucleus and chloroplast. The PtAGOs had similar motif structures and conserved motifs, except for PtAGO3. All the PtAGO genes could be clustered into 3 groups, and Group II, including PtAGO2/3/7, had the smallest number of exons, while the others had more than 20 exons. Cis-regulatory elements involved in light response, growth and development, abiotic stress and hormone-induced responses were found in the promoters of PtAGO members. Further expression analysis found that the PtAGO genes had tissue-specific expression patterns. For example, PtAGO7 and PtAGO10b were mainly expressed in the xylem and might be involved in secondary xylem development. Furthermore, abiotic stress tests, including heat, ABA and PEG treatments, showed that most PtAGO genes could respond quickly to ABA treatment, and multiple PtAGO genes were constantly regulated under heat-shock stress. These results provide a basis for the elucidation mechanism of PtAGO genes and further molecular breeding in poplar.
The Role of Malt on Beer Flavour Stability
Authors: Guido Luis F. , Ferreira Inês M.
Published: May 2023

Delaying flavour staling has been one of the greatest and most significant challenges for brewers. The choice of suitable raw materials, particularly malting barley, is the critical starting point to delay the risk of beer staling. Malting barley and the malting process can have an impact on beer instability due to the presence of pro-oxidant and antioxidant activities. Malt contains various compounds originating from barley or formed during the malting process, which can play a significant role in the fundamental processes of brewing through their antioxidant properties. This review explores the relationship between malt quality, in terms of antioxidant and pro-oxidant activities, and the flavour stability of beer.
A Review on the Interspecies Electron Transfer of Methane Production in Anaerobic Digestion System
Authors: Su Kai , Li Linxiao , Wang Qin , Cao Rong
Published: May 2023

Anaerobic methanogenesis plays an important role in the sustainable management of high concentration organic wastewater and bioenergy recovery. Interspecies electron transfer (IET) is a new type of mutualistic symbiosis that can accelerate microbial metabolism and overcome thermodynamic barriers in the metabolic process, thus facilitating anaerobic methanogenesis. IET is classified into Direct Interspecies Electron Transfer (DIET) and Mediated Interspecies Electron Transfer (MIET) according to the different electron transfer methods. This paper summarizes the recent research progress related to interspecies microbial electron transfer in anaerobic methanogenic system, describes the possible specific mechanisms of DIET and MIET, and analyzes the differences between DIET and MIET methods in terms of methanogenic performance, thermodynamics, kinetics, and the microbial communities involved in them. Finally, it was found that, through DIET, microorganisms in the process of anaerobic methanogenesis could not only strengthen the extracellular electron transfer of microorganisms and alleviate the inhibition of high organic loading rate, organic acids, and toxic substances, they could also help ferment bacteria and allow methanogenesis to break through the thermodynamic barriers and efficiently degrade complex organic matter. This can overcome several problems, such as low efficiency of electron transfer and acidification of traditional anaerobic digestion.
Enhancing the Activity of a Self-Inducible Promoter in Escherichia coli through Saturation Mutation and High-Throughput Screening
Authors: Li Jinyang , Tong Sheng , Amin Farrukh Raza , Khalid Habiba , Chen Kai , Zhao Xiaoguang , Cai Jinling , Li Demao
Published: May 2023

The use of self-inducible promoters is a promising strategy to address metabolic imbalances caused by overexpression. However, the low activity of natural self-inducible promoters hinders their widespread application. To overcome this limitation, we selected the fic promoter as a model promoter to create an enhanced self-inducible promoter library using saturation mutations and high-throughput screening. Sequence analysis revealed that these promoters share certain characteristics, including semi-conservation in the −35 hexamer, highly conserved cytosine in the −17 motif (compared to −13 for other promoters), and moderate A+T content between positions −33 and −18 in the spacer region. Additionally, the discriminator region of these promotors features high A+T content in the first five bases. We identified PficI-17, PficII-33, and PficIII-14 promoters as the optional promoters in the −35 hexamer, spacer region, and discriminator mutation libraries, respectively. These promotors were used as representatives to measure the specific fluorescence and OD600 nm dynamics in different media and to confirm their effect on the expression of different proteins, including egfp (enhanced green fluorescence protein) and rfp (red fluorescence protein). Overall, our findings provide valuable guidance for modifying promoters and developing a promoter library suitable for regulating target genes.
Microbiome Characterization after Aerobic Digestate Reactivation of Anaerobically Digested Sewage Sludge
Authors: Otto Pascal , Alipoursarbani Mozhdeh , Torrent Daniel , Latorre-Pérez Adriel , Paust Thomas , Albert Alfred , Abendroth Christian
Published: May 2023

A demonstrator plant of a recently patented process for improved sludge degradation has been implemented on a municipal scale. In a 1500 m3 sewage sludge digester, an intermediary stage with aerobic sewage sludge reactivation was implemented. This oxic activation increased the biogas yield by up to 55% with a 25% reduction of the remaining fermentation residue volume. Furthermore, this process allowed an NH4-N removal of over 90%. Additionally, 16S rRNA gene amplicon high-throughput sequencing of the reactivated digestate showed a reduced number of methane-forming archaea compared to the main digester. Multiple ammonium-oxidizing bacteria were detected. This includes multiple genera belonging to the family Chitinophagaceae (the highest values reached 18.8% of the DNA sequences) as well as a small amount of the genus Candidatus nitrosoglobus (<0.3%). In summary, the process described here provides an economically viable method to eliminate nitrogen from sewage sludge while achieving higher biogas yields and fewer potential pathogens in the residuals.
Efficient Mobile Sink Routing in Wireless Sensor Networks Using Bipartite Graphs
Authors: Abu Taleb Anas , Abu Al-Haija Qasem , Odeh Ammar
Published: May 2023

Wireless sensor networks (W.S.N.s) are a critical research area with numerous practical applications. W.S.N.s are utilized in real-life scenarios, including environmental monitoring, healthcare, industrial automation, smart homes, and agriculture. As W.S.N.s advance and become more sophisticated, they offer limitless opportunities for innovative solutions in various fields. However, due to their unattended nature, it is essential to develop strategies to improve their performance without draining the battery power of the sensor nodes, which is their most valuable resource. This paper proposes a novel sink mobility model based on constructing a bipartite graph from a deployed wireless sensor network. The proposed model uses bipartite graph properties to derive a controlled mobility model for the mobile sink. As a result, stationary nodes will be visited and planned to reduce routing overhead and enhance the network’s performance. Using the bipartite graph’s properties, the mobile sink node can visit stationary sensor nodes in an optimal way to collect data and transmit it to the base station. We evaluated the proposed approach through simulations using the NS-2 simulator to investigate the performance of wireless sensor networks when adopting this mobility model. Our results show that using the proposed approach can significantly enhance the performance of wireless sensor networks while conserving the energy of the sensor nodes.
A Method to Directly Identify Cronobacter sakazakii in Liquid Medium by MALDI-TOF MS
Authors: Song Danliangmin , Su Qunchao , Jia Ai , Fu Shiqian , Ma Xiaoming , Li Tiantian , Man Chaoxin , Yang Xinyan , Jiang Yujun
Published: May 2023

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry has been widely used as an emerging technology for the rapid identification of microorganisms. Cronobacter sakazakii (C. sakazakii) is a food-borne pathogen of particular importance to the powdered infant formula (PIF) processing environment due to its high lethality in infants. However, the traditional solid spotting detection method of pretreating samples for MALDI-TOF MS leads only to qualitative detection of C. sakazakii. We developed a new, low-cost, robust liquid spotting pretreatment method and used a response surface methodology to optimize its parameters. The applicability, accuracy, and quantitative potential were measured for different types of samples. The optimal parameters of this method were as follows: a volume of 70% formic acid of 25 μL, treatment with ultrasound at 350 W for 3 min, and a volume of acetonitrile added of 75 μL. These conditions led to the highest identification score for C. sakazakii (1926.42 ± 48.497). This method was found to detect bacteria accurately and reproducibly. When 70 strains of C. sakazakii isolates were analyzed with this method, the identification accuracy was 100%. The detection limit of C. sakazakii in environmental and PIF samples was 4.1 × 101 cfu/mL and 2.72 × 103 cfu/mL, respectively.