bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Dietary Fiber, Crude Protein Level, and Gestation Stage on the Nitrogen Utilization of Multiparous Gestating Sows
Authors: Yang Min , Hua Lun , Mao Zhengyu , Lin Yan , Xu Shengyu , Li Jian , Jiang Xuemei , Wu De , Zhuo Yong , Huang Jiankui
Published: June 2022

To investigate the effects of dietary fiber (DF), crude protein (CP) level, and gestation stage on nitrogen utilization, 28 Landrace-Yorkshire cross gestating sows at parity two were randomly divided into four dietary treatments with seven duplicates of one pig with a repeated-measures design. The diets comprised one with normal crude protein (CP) of 13.3%, one with a low CP diet of 10.1%, and two diets, one with dietary fiber (DF) supplementation of inulin and cellulose at the ratio of 1:1 and one without DF. The total litter size, litter size alive, and newborn birthweight of piglets did not differ between treatment groups. Sows that received high DF levels had greater nitrogen output in feces, lower urinary nitrogen, and increased nitrogen retention. Sows that received a low CP diet had reduced nitrogen excretion in feces and urine, lower nitrogen retention, and an unchanged nitrogen retention ratio. Sows at the late stage of gestation on days 95 to 98 had lower nitrogen excretion in urine and greater nitrogen retention than in the early stage of gestation on days 35 to 38, associated with a significant decrease in serum amino acids in late gestation. Maternal protein deposition was increased by high DF, decreased by low CP, and lower in late gestation compared with early gestation. Collectively, DF improved nitrogen utilization by decreasing urine nitrogen output, and nitrogen utilization increased as gestation advanced.
An IoT-Based Breeding Egg Identification and Coding System for Selection of High-Quality Breeding Geese
Authors: Zhang Yanjun , Ge Yujie , Yang Tian , Guo Yangyang , Yang Jian , Han Jiawen , Gong Daoqing , Miao Hong
Published: June 2022

The selection of breeding geese requires the recording of egg production information to correspond to the identity of the breeding geese. However, due to the special physiological characteristics of breeding geese, manual recording in practice can affect the egg-laying performance of breeding geese and can also lead to problems of missing and confusing individual breeding goose data with the number of eggs laid by the geese. For contactless recording of breeding goose identity and egg production information for high-quality breeding, this paper proposes an Internet of things (IoT)-based breeding egg identification and coding method for the selection of high-quality breeding geese. At the sensing level, we deployed a radiofrequency identification (RFID)-based sensor. Each breeding goose wore a foot ring RFID tag on its leg, and the individual information was read by foot ring RFID readers placed at the bottom of the devices. Individual information was uploaded to the cloud server for database management through structured query language (MySQL). The target detection modules were mounted on top of the devices, and the breeding geese and eggs were detected in the delivery rooms by an improved single-shot multi-box detector (SSD) target detection algorithm. The egg body limit transmission device and contactless coding device were activated only in the case of breeding eggs, and the breeding goose information was printed on the egg bodies in the form of quick response codes (QR codes), which enabled the breeding egg information to correspond with the breeding goose information. An evaluative experiment was performed using a system for the selection of high-quality breeding geese, with web cameras and a cloud monitoring platform. The breeding geese were allowed 14 days to become accustomed to the experimental environment before monitoring began. The evaluative experiment results showed that the pass rate of egg body coding reached 98.25%, the improved SSD algorithm was 8.65% more accurate and 62.6 ms faster than traditional SSD, and the accuracy rate corresponding to the individual information of the breeding geese and the surface information of the goose eggs was 97.8%. The experimental results met the requirements of accurate marking of individual information of breeding geese, which can provide technical support for the selection of high-quality breeding geese.
Optimized Synthesis of Small and Stable Silver Nanoparticles Using Intracellular and Extracellular Components of Fungi: An Alternative for Bacterial Inhibition
Authors: Murillo-Rábago Elvira Ivonne , Vilchis-Nestor Alfredo R. , Juarez-Moreno Karla , Garcia-Marin Luis E. , Quester Katrin , Castro-Longoria Ernestina
Published: June 2022

Silver nanoparticles (AgNPs) represent an excellent option to solve microbial resistance problems to traditionally used antibiotics. In this work, we report optimized protocols for the production of AgNPs using extracts and supernatants of Trichoderma harzianum and Ganoderma sessile. AgNPs were characterized using UV-Vis spectroscopy and transmission electron microscopy, and the hydrodynamic diameter and Z potential were also determined. The obtained AgNPs were slightly larger using the fungal extract, and in all cases, a quasi-spherical shape was obtained. The mean sizes of AgNPs were 9.6 and 19.1 nm for T. harzianum and 5.4 and 8.9 nm for G. sessile using supernatant and extract, respectively. The AgNPs were evaluated to determine their in vitro antibacterial effect against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The minimum inhibitory concentration (MIC) was determined, and in all cases the AgNPs showed an antimicrobial effect, with a MIC varying from 1.26–5.0 µg/mL, depending on the bacterial strain and type of nanoparticle used. Cytotoxicity analyses of AgNPs were carried out using macrophages and fibroblast cell lines. It was determined that the cell viability of fibroblasts exposed for 24 h to different concentrations of AgNPs was more than 50%, even at concentrations of up to 20 µg/mL of silver. However, macrophages were more susceptible to exposure at higher concentrations of AgNPs as their viability decreased at concentrations of 10 µg/mL. The results presented here demonstrate that small AgNPs are obtained using either supernatants or extracts of both fungal strains. A remarkable result is that very low concentrations of AgNPs were necessary for bacterial inhibition. Furthermore, AgNPs were stable for more than a year, preserving their antibacterial properties. Therefore, the reported optimized protocol using fungal supernatants or extracts may be used as a fast method for synthesizing small AgNPs with high potential to use in the clinic.
Antiplasmodial Cyclodecapeptides from Tyrothricin Share a Target with Chloroquine
Authors: Leussa Adrienne N.-N. , Rautenbach Marina
Published: June 2022

Previous research found that the six major cyclodecapeptides from the tyrothricin complex, produced by Brevibacillus parabrevis, showed potent activity against chloroquine sensitive (CQS) Plasmodium falciparum. The identity of the aromatic residues in the aromatic dipeptide unit in cyclo-(D-Phe1-Pro2-(Phe3/Trp3)-D-Phe4/D-Trp4)-Asn5-Gln6-(Tyr7/Phe7/Trp7)-Val8-(Orn9/Lys9)-Leu10 was proposed to have an important role in activity. CQS and resistant (CQR) P. falciparum strains were challenged with three representative cyclodecapeptides. Our results confirmed that cyclodecapeptides from tyrothricin had significantly higher antiplasmodial activity than the analogous gramicidin S, rivaling that of CQ. However, the previously hypothesized size and hydrophobicity dependent activity for these peptides did not hold true for P. falciparum strains, other than for the CQS 3D7 strain. The Tyr7 in tyrocidine A (TrcA) with Phe3-D-Phe4 seem to be related with loss in activity correlating with CQ antagonism and resistance, indicating a shared target and/or resistance mechanism in which the phenolic groups play a role. Phe7 in phenycidine A, the second peptide containing Phe3-D-Phe4, also showed CQ antagonism. Conversely, Trp7 in tryptocidine C (TpcC) with Trp3-D-Trp4 showed improved peptide selectivity and activity towards the more resistant strains, without overt antagonism towards CQ. However, TpcC lead to similar parasite stage inhibition and parasite morphology changes than previously observed for TrcA. The disorganization of chromatin packing and neutral lipid structures, combined with amorphous hemozoin crystals, could account for halted growth in late trophozoite/early schizont stage and the nanomolar non-lytic activity of these peptides. These targets related to CQ antagonism, changes in neural lipid distribution, leading to hemozoin malformation, indicate that the tyrothricin cyclodecapeptides and CQ share a target in the malaria parasite. The differing activities of these cyclic peptides towards CQS and CQR P. falciparum strains could be due to variable target interaction in multiple modes of activity. This indicated that the cyclodecapeptide activity and parasite resistance response depended on the aromatic residues in positions 3, 4 and 7. This new insight on these natural cyclic decapeptides could also benefit the design of unique small peptidomimetics in which activity and resistance can be modulated.
Editorial for the Special Issue: “Epidemiology, Prognosis and Antimicrobial Treatment of Extensively Antibiotic-Resistant Bacterial Infections”
Authors: Karakonstantis Stamatis , Kritsotakis Evangelos I.
Published: June 2022

The increasing consumption of broad-spectrum antimicrobials is fuelling a vicious cycle leading to extensively drug-resistant (XDR) and pandrug-resistant (PDR) bacteria [...]
Direct Derivatization in Dried Blood Spots for Oxidized and Reduced Glutathione Quantification in Newborns
Authors: Ten-Doménech Isabel , Solaz-García Álvaro , Lara-Cantón Inmaculada , Pinilla-Gonzalez Alejandro , Parra-Llorca Anna , Vento Máximo , Quintás Guillermo , Kuligowski Julia
Published: June 2022

The glutathione (GSH)-to-glutathione disulfide (GSSG) ratio is an essential node contributing to intracellular redox status. GSH/GSSG determination in whole blood can be accomplished by liquid chromatography–mass spectrometry (LC-MS) after the derivatization of GSH with N-ethylmaleimide (NEM). While this is feasible in a laboratory environment, its application in the clinical scenario is cumbersome and therefore ranges reported in similar populations differ noticeably. In this work, an LC-MS procedure for the determination of GSH and GSSG in dried blood spot (DBS) samples based on direct in situ GSH derivatization with NEM of only 10 µL of blood was developed. This novel method was applied to 73 cord blood samples and 88 residual blood volumes from routine newborn screening performed at discharge from healthy term infants. Two clinical scenarios simulating conditions of sampling and storage relevant for routine clinical analysis and clinical trials were assessed. Levels of GSH-NEM and GSSG measured in DBS samples were comparable to those obtained by liquid blood samples. GSH-NEM and GSSG median values for cord blood samples were significantly lower than those for samples at discharge. However, the GSH-NEM-to-GSSG ratios were not statistically different between both groups. With DBS testing, the immediate manipulation of samples by clinical staff is reduced. We therefore expect that this method will pave the way in providing an accurate and more robust determination of the GSH/GSSG values and trends reported in clinical trials.
Identification and Quantification of Urinary Microbial Phenolic Metabolites by HPLC-ESI-LTQ-Orbitrap-HRMS and Their Relationship with Dietary Polyphenols in Adolescents
Authors: Laveriano-Santos Emily P. , Marhuenda-Muñoz María , Vallverdú-Queralt Anna , Martínez-Huélamo Miriam , Tresserra-Rimbau Anna , Miliarakis Elefterios , Arancibia-Riveros Camila , Jáuregui Olga , Ruiz-León Ana María , Castro-Baquero Sara , Estruch Ramón , Bodega Patricia , Miguel Mercedes de , Cos-Gandoy Amaya de , Martínez-Gómez Jesús , Santos-Beneit Gloria , Fernández-Alvira Juan M. , Fernández-Jiménez Rodrigo , Lamuela-Raventós Rosa M.
Published: June 2022

This study aimed to develop and validate a liquid chromatography/electrospray ionization-linear ion trap quadrupole-Orbitrap-high-resolution mass spectrometry (HPLC/ESI-LTQ-Orbitrap-HRMS) method to identify and quantify urinary microbial phenolic metabolites (MPM), as well as to explore the relationship between MPM and dietary (poly)phenols in Spanish adolescents. A total of 601 spot urine samples of adolescents aged 12.02 ± 0.41 years were analyzed. The quantitative method was validated for linearity, limit of detection, limit of quantification, recovery, intra- and inter-day accuracy and precision, as well as postpreparative stability according to the criteria established by the Association of Official Agricultural Chemists International. A total of 17 aglycones and 37 phase II MPM were identified and quantified in 601 spot urine samples. Phenolic acids were the most abundant urinary MPM, whereas stilbenes, hydroxytyrosol, and enterodiol were the least abundant. Urinary hydroxycoumarin acids (urolithins) were positively correlated with flavonoid and total (poly)phenol intake. An HPLC-ESI-LTQ-Orbitrap-HRMS method was developed and fully validated to quantify MPM. The new method was performed accurately and is suitable for MPM quantification in large epidemiological studies. Urinary lignans and urolithins are proposed as potential biomarkers of grain and nut intake in an adolescent population.
HO-1 Limits the Efficacy of Vemurafenib/PLX4032 in BRAFV600E Mutated Melanoma Cells Adapted to Physiological Normoxia or Hypoxia
Authors: Furfaro Anna Lisa , Loi Giulia , Ivaldo Caterina , Passalacqua Mario , Pietra Gabriella , Mann Giovanni Enrico , Nitti Mariapaola
Published: June 2022

Induction of heme oxygenase 1 (HO-1) favors immune-escape in BRAFV600 melanoma cells treated with Vemurafenib/PLX4032 under standard cell culture conditions. However, the oxygen tension under standard culture conditions (~18 kPa O2) is significantly higher than the physiological oxygen levels encountered in vivo. In addition, cancer cells in vivo are often modified by hypoxia. In this study, MeOV-1 primary melanoma cells bearing the BRAFV600E mutation, were adapted to either 5 kPa O2 (physiological normoxia) or 1 kPa O2 (hypoxia) and then exposed to 10 μM PLX4032. PLX4032 abolished ERK phosphorylation, reduced Bach1 expression and increased HO-1 levels independent of pericellular O2 tension. Moreover, cell viability was significantly reduced further in cells exposed to PLX4032 plus Tin mesoporphyrin IX, a HO-1 inhibitor. Notably, our findings provide the first evidence that HO-1 inhibition in combination with PLX4032 under physiological oxygen tension and hypoxia restores and increases the expression of the NK ligands ULBP3 and B7H6 compared to cells exposed to PLX4032 alone. Interestingly, although silencing NRF2 prevented PLX4032 induction of HO-1, other NRF2 targeted genes were unaffected, highlighting a pivotal role of HO-1 in melanoma resistance and immune escape. The present findings may enhance translation and highlight the potential of the HO-1 inhibitors in the therapy of BRAFV600 melanomas.
Production of Collagens and Protein Hydrolysates with Antimicrobial and Antioxidant Activity from Sheep Slaughter By-Products
Authors: Vidal Alessandra Roseline , Cansian Rogério Luis , Mello Renius de Oliveira , Demiate Ivo Mottin , Kempka Aniela Pinto , Dornelles Rosa Cristina Prestes , Rodriguez José Manuel Lorenzo , Campagnol Paulo Cezar Bastianello
Published: June 2022

This work aimed to produce collagens and hydrolysates with antimicrobial and antioxidant activity from sheep slaughter by-products. The by-products (sheep and lamb) were treated and extracted. The collagens were hydrolyzed with the enzyme Alcalase®. The spectra of collagens and hydrolysates were similar (amide bands I, II, III, A, B). The bands presented by the collagens (α1, α2, β) were characteristic of type I collagen. The hydrolysates showed molecular weight peptides equal to/lower than 15 kDa. Collagens had a denaturation temperature of 39.32 (lamb) and 36.38 °C (sheep), whereas the hydrolysates did not undergo thermal transition. Hydrolysates showed lower values of antioxidant activity (AA) than the collagens. The collagens from lamb and from sheep displayed an AA of 13.4% (concentration of 0.0002%) and 13.1% (concentration of 0.0005%), respectively. At the concentration of 0.0020%, the lamb hydrolysates displayed an AA of 10.2%, whereas the sheep hydrolysates had an AA of only 1.98%. Collagen also showed higher antimicrobial activity compared to hydrolysates, requiring a lower concentration to inhibit the microorganisms tested. Sheep slaughter by-products proved to be a viable source for obtaining protein hydrolysates and collagens with antimicrobial and antioxidant activity, which can be applied in the development of nutraceuticals beneficial to human health.
Effect of Coupled Mechanical-Chemical Activation on Hydration Activity of Copper Slag Powder
Authors: Zhu Jielu , Li Qi , Li Xianglan , Zhou Yanhua , Liu Fanghua , Song Junwei
Published: June 2022

In order to investigate the effect and mechanism of coupled mechanical–chemical activation on the hydration activity of copper slag powder, copper slag powder with different grinding time and content was applied to prepare composite cement. The hydration heat and rate of the composite cement paste were tested for 120 h. The mechanical properties and microstructure of the samples were characterized by compressive strength activity index, XRD, and SEM. The findings revealed that the specific surface area of the copper slag powder increased by 27.84%, 20.14%, and 10.92%, respectively, when the grinding time increased from 30 min to 120 min. The particle size distribution of the copper slag powder after grinding for 90 min and 120 min was superior to that of cement. The compressive strength activity index of the paste specimen increased with the extension of the copper slag grinding time when the copper slag powder content remained constant. Chemical activator CaO further stimulated the hydration activity of copper slag powder, increased the hydration heat of copper slag powder-based composite cement paste, and promoted the compressive strength of composite cement-hardened paste at different ages. With the increase in copper slag powder content, the porosity of the hardened paste increased, resulting in a decrease in compressive strength at different ages.
Efficient Intersection Management Based on an Adaptive Fuzzy-Logic Traffic Signal
Authors: Madrigal Arteaga Victor Manuel , Pérez Cruz José Roberto , Hurtado-Beltrán Antonio , Trumpold Jan
Published: June 2022

Traffic signals may generate bottlenecks due to an unfair timing balance. Facing this problem, adaptive traffic signal controllers have been proposed to compute the phase durations according to conditions monitored from on-road sensors. However, high hardware requirements, as well as complex setups, make the majority of these approaches infeasible for most cities. This paper proposes an adaptive traffic signal fuzzy-logic controller which uses the flow rate, retrieved from simple traffic counters, as a unique input requirement. The controller dynamically computes the cycle duration according to the arrival flow rates, executing a fuzzy inference system guided by the reasoning: the higher the traffic flow, the longer the cycle length. The computed cycle is split into different phases proportionally to the arrival flow rates according to Webster’s method for signalization. Consequently, the controller only requires determining minimum/maximum flow rates and cycle lengths to establish if–then mappings, allowing the reduction of technical requirements and computational overhead. The controller was tested through a microsimulation model of a real isolated intersection, which was calibrated with data collected from a six-month traffic study. Results revealed that the proposed controller with fewer input requirements and lower computational costs has a competitive performance compared to the best and most used approaches, being a feasible solution for many cities.
Effect of Process Parameters on Tensile Strength of FDM Printed Carbon Fiber Reinforced Polyamide Parts
Authors: Muhamedagic Kenan , Berus Lucijano , Potočnik David , Cekic Ahmet , Begic-Hajdarevic Derzija , Cohodar Husic Maida , Ficko Mirko
Published: June 2022

Reinforcing the polymer with nanoparticles and fibers improves the mechanical, thermal and electrical properties. Owing to this, the functional parts produced by the FDM process of such materials can be used in industrial applications. However, optimal parameters’ selection is crucial to produce parts with optimal properties, such as mechanical strength. This paper focuses on the analysis of influential process parameters on the tensile strength of FDM printed parts. Two statistical methods, RSM and ANN, were applied to investigate the effect the layer thickness, printing speed, raster angle and wall thickness on the tensile strength of test specimens printed with a short carbon fiber reinforced polyamide composite. The reduced cubic model was developed by the RSM method, and the correlation between the input parameters and the output response was analyzed by ANOVA. The results show that the layer thickness and raster angle have the most significant influence on tensile strength. As for machine learning, among the nine different tested ANN topologies, the best configuration was found based on the lowest MAE and MSE test sample result. The results show that the proposed model could be a useful tool for predicting tensile strength. Its main advantage is the reduction in time needed for experiments with the LOSO (leave one subject out) k-fold cross validation scheme, offering better generalization ability, given the small set of learning examples.
Machining Strategy and Experimental Study of Ultrasonic-Assisted Bidirectional Progressive Spiral Milling of Carbon Fiber Holes
Authors: Wang Changhong , Chen Tao , Wang Guangyue , Xu Wenyuan
Published: June 2022

Carbon fiber-reinforced composites (CFRP) are widely used in aerospace structural holes due to their superior mechanical properties. However, fiber pulling, delamination, burr and other defects often occur in the parts, which seriously affect the accuracy and service life of the products. The traditional cylindrical milling cutter is easy to lead to the exit delamination defects due to the large axial force at the bottom edge, concentrated wear at the periphery edge, and weak rigid constraint at the exit machining position. Therefore, this paper proposed a new hole machining strategy, analyzed the kinematic law of the tapered progressive spiral milling hole, studied the cutting mechanism of the four stages of the tapered spiral bidirectional milling hole, explored the material removal force state of the ultrasonic augment-assisted progressive milling hole, and established the prediction of the layered axial force of the ultrasonic progressive milling hole. Finally, combined with the material removal mechanism of ultrasonic vibration, the self-designed bidirectional progressive spiral milling cutter was used to verify the mechanism of material removal by progressive milling, in which the axial force could be effectively reduced. After 60 and 90 holes were processed, the axial force was about 18.5 and 23.3 N, respectively, the critical force of delamination could be improved, and the hole quality could be guaranteed without obvious burr and delamination phenomena.
Roboethics in Remote Human Interactions and Rehabilitative Therapeutics
Authors: Maddahi Ali , Leach Tracy R. , Saeedi Mohammad , Dhannapuneni Pruthvinath R. , Maddahi Yaser , Choukou Mohamed-Amine , Zareinia Kourosh
Published: June 2022

Global aging, the need for continuous high-quality services, and the recent COVID-19 pandemic have caused many sectors to reduce in-person contact between individuals where possible, and to instead use remote communication technology. With increased robot use replacing in-person interventions, ethical considerations arise. The benefits of robotic technology must be weighed against the possibility of harm to humans. The first rules of roboethics were written by Isaac Asimov in 1942, but these pre-date the range of robotic applications used today. There is no central agency for oversight in Canada, although universities and funding organizations have developed guidelines. Roboethical considerations include data use and privacy, the common good, and safety. Humans may potentially form emotional bonds with robots. Loss of jobs to automation is also a concern, particularly when many workers have suffered job losses due to the pandemic. Some health care services have switched to a remote care model, to reduce the spread of COVID-19. Remote hand rehabilitation of patients with brain injury is possible with iManus. Using a portable smart-glove technology, patients practice rehabilitative hand movements that are analyzed remotely through a sensor that offers instantaneous feedback. A therapist monitors their patient’s progress remotely and designs individualized programs. This technology benefits humanity by improving access to care for patients globally. The importance of data security and privacy is emphasized. As patient progress will be monitored by a human (a therapist), the safety of iManus is not a concern. The principles discussed in this paper can help researchers and engineers design ethical robotics in remote health care settings.
Parasitic Parameters Extraction of High-Speed Vertical-Cavity Surface-Emitting Lasers
Authors: Tong Haixia , Wang Yanjing , Tian Sicong , Tong Cunzhu , Wei Zhipeng , Wang Lijun
Published: June 2022

Parasitic parameters, including electrical capacity and inductance, are the key limiting factors for bandwidth improvement of high-speed vertical-cavity surface-emitting lasers (VCSELs). The traditional parasitic extraction method, which uses a first-order low-pass filter transfer function, is oversimplified, and there are large deviations between the obtained data and the actual measured data. In this paper, we proposed a modified parasitic extraction method that described the extrinsic behaviour of the high-speed oxide-confined VCSELs well and easily extracted the values of all parasitic parameters. This method can also precisely fit microwave reflection coefficient S11 data even at high frequencies and provide design guidance for high-speed VCSELs. Using this method, a high-speed 850 nm VCSEL featuring a six-layer oxide aperture with −3 dB bandwidth up to 23.3 GHz was analysed. The electrical parasitics have been systematically extracted from VCSELs with different oxide apertures. The enhanced bandwidth based on the improvement of parasitic parameters was discussed. It was found that the critical parasitic factors that affect the −3 dB bandwidth of VCSELs are pad capacitance and inductance.
Monitoring the Geometric Position of Transition Zones to Increase the Quality and Safety of Railway Lines
Authors: Hodas Stanislav , Izvoltova Jana , Chromcak Jakub , Bacova Dasa
Published: June 2022

Transition zones on railway lines are localities with gradual changes in the construction layers in the connections between a fixed track and ballasted track or between a wide track and various railway objects, e.g., tunnels, bridges, culverts, etc. The different type of construction of transition zones causes a shock wave when the train passes, which can cause undesired effects on the stability of its construction, durability, and passengers’ comfort. For this reason, railway opera-tors pay increased attention to the construction inspection of these transition sections. The research deals with the description of the transition zones, methods, and results of their monitoring in experimental sections of the railway corridors. Innovative aspects are the measurements made using precise geodetic instruments as well as continuous measurements with the KRAB trolley. The analyses of measurements in the experimental sections of the track show whether the stability of the geometric spatial position is ensured.
Ship’s Digital Twin—A Review of Modelling Challenges and Applications
Authors: Assani Nur , Matić Petar , Katalinić Marko
Published: June 2022

The Ship’s Digital Twin (SDT) is a digital record of a ship’s behaviour or a software clone, which can be used to simulate scenarios that are expensive or hardly feasible to perform on a real object and especially in real time. The purpose of the SDT is to achieve cost reduction, obtain timely warnings of irregularities, and optimise individual ship system performances or the operation of the whole ship and to assist ship management. The aim of this paper is to describe the concept of the SDT and clarify some perplexities that may occur from initial introduction to concept. To that end, the paper identifies the steps in the SDT formulation process and methods used in each step of the process. Furthermore, a four-step iterative procedure for the SDT development is proposed. The applications of the concept are numerous, and some of them are presented in a review analysis in this paper. The presented analysis leads to a conclusion that should give some direction to future research in this area.
Modification of Segment Structure Calculation Theory and Development and Application of Integrated Software for a Shield Tunnel
Authors: Huang Qingfei , Liu Shaopeng , Lv Yonggang , Ji Daxue , Li Pengfei
Published: June 2022

From the aspect of calculation theory, the beam–spring model method and modified routine method of shield tunnel segment structure calculation were improved, and an efficient integrated software system for segment structure calculation of shield tunnel was developed. The beam–spring method is generally calculated according to the assumption of continuous displacement between beams and joints, and the existing modified routine method assumes that the lateral pressure gradient is constant generally, which does not consider the variation in lateral pressure gradient caused by the difference in the lateral pressure coefficient of soil layers or the water level height, which has a certain deviation from the actual situation. The existing beam–spring method and modified routine method theory were improved, the discontinuous displacement between beams and joints in the beam–spring method was taken into account, and the problem of lateral pressure gradient change in the modified routine method was solved. The calculation software system developed by C# and python programming language was proposed to improve the accuracy and efficiency of segment structure calculation. Based on the actual monitoring data of the internal force of the shield tunnel segment and the adjacent shield tunnel segments under construction in Changsha, China, the segments of the shield tunnel with different cross-section sizes and different hydrogeological conditions are calculated to verify the reliability of the calculation software system. At the same time, combined with the calculation results of the software system and field test data, the stiffness reduction coefficient and equivalent foundation resistance coefficient in the modified routine method were derived to further improve the accuracy of the calculation results, which provided a new idea for the calculation of segment structure of shield tunnel with different diameters under different hydrogeological conditions.
Application of Statistical Process Control for Structural Health Monitoring of a High-Speed Railway Track System
Authors: Zhang Yanrong , Wu Kai , Yu Chao , Zhang Shuang , Cai Xiaopei
Published: June 2022

To make full use of the massive monitoring data accumulated in China high-speed railways, an improved statistical process control (SPC) framework was introduced to analyze the discontinuous monitoring data of the track system on a high-speed railway elevated station. Multilinear regression models and time series difference equation (TSDE) models were first developed to separate common-cause variations in the monitoring data. Then, individual control charts, moving range control charts, and exponentially weighted moving average control charts were constructed to detect special-cause variations. Results showed that the variations of girder displacement and track slab–girder relative displacements mainly resulted from temperature effects and linear trends related with material damages. Moreover, visible serial dependence was found in the regression model residuals, which could be effectively captured by the TSDE model. Numerous outliers were detected at the measuring points of rail–track slab displacement 15 and track slab–girder relative displacement 17 by more than three control charts, implying higher sensitivity to special causes. With respect to the special causes triggering the anomalous responses of local and overall track systems, sixteen and twenty-eight significant special events were detected, respectively.
The Effect of Fines Content on Compressional Behavior When Using Sand–Kaolinite Mixtures as Embankment Materials
Authors: Kaothon Panyabot , Lee Su-Hyung , Choi Yeong-Tae , Yune Chan-Young
Published: June 2022

In South Korea, Honam High-Speed Railway has a relatively large residual settlement issue and high fines content has been pointed out as one of the causes. Design guidelines regulate not to use soils containing fines content higher than 25%. However, there is no background information on the effect of fines content on settlement. Therefore, this paper aims to investigate compressional behavior according to fines content using sand and kaolinite. Oedometer test results showed that the compression index is lowest with fines content of 15% to 20% at which the mixture produced maximum density. The optimum fines content for inducing low settlement would be 15% to 20% for the sand–kaolinite mixture. Transition fines content (TFC), which shows sand-like to claylike behavior, was observed to have between 21% and 26% of fines content. Critical fines content (fcrit) where a minimum void ratio occurs was estimated as 21.67%. These behavioral changes appear when fines content is greater than the optimum fines content. SEM also shows that the kaolinite particles were overlapped, creating flat surfaces with a fines content higher than 30%, and showing clay-like behavior. Based on the analysis results, engineers can simply identify the behavior of embankment materials to ensure optimum fines content and consequently minimize long-term settlement potential.
Experimental Study on the Shear Strength of Silt Treated by Xanthan Gum during the Wetting Process
Authors: Zhang Junran , Meng Zhihao , Jiang Tong , Wang Shaokai , Zhao Jindi , Zhao Xinxin
Published: June 2022

Traditional materials such as fly ash and lime are generally used to improve soils but can severely pollute the environment. Eco-friendly protocols, such as the application of xanthan gum, are therefore essential for soil treatment. In this study, a series of microscopic tests, water retention characteristics tests, and shear tests were carried out on silt, which are known to have poor engineering properties, to explore the effect and mechanism of xanthan gum treatment on the water retention and shear strength characteristics of silt during the wetting process. The results show that the water retention capacity of the treated silt increases with increasing xanthan gum content, and a hysteresis effect is clearly observed. The cohesion and internal friction angle of the silt strongly decrease with increasing water content, and the strength significantly weakens. However, the strength of the silt treated with xanthan gum is consistently higher than that of the untreated silt. The microscopic tests show that soil pores are gradually filled by xanthan gum with good water-retaining properties, thus significantly enhancing the water retention capacity. Furthermore, the hydrogel that cements the soil particles forms by the bonding effects between xanthan gum and soil particles, which greatly improves the silt strength.
Characterization of Electromagnetic Pulses Generated from Plasma Associated with Laser Filaments-Excited Aluminum Alloy Interaction
Authors: Qi Rong , Zhou Chuliang , Zhang Dongdong , Song Liwei , Yang Xiaojun , Gui Jiayan , Leng Yuxin , Tian Ye , Li Ruxin
Published: June 2022

Femtosecond laser filament-generated plasma can generate electromagnetic pulses (EMPs). These pulses may reduce the instrument’s precision, and, hence, influence the accuracy of the experimental results. They may even cause widespread disruption by disabling of the electronic control systems or distribution networks of power plants. This study investigated the characteristics of EMPs generated from the interaction of filament-generated plasmas with a solid target in air. In this study, ultrafast laser filamentation was used to produce plasma, which was focused on a 3 mm-thick aluminum (Al) alloy target for interaction, and the spatial distribution and main contributors of the EMPs were systematically and extensively studied. The results showed that the EMPs generated from ultrafast laser filament interaction with the Al alloy target had the following characteristics: the EMP energy generated from laser filament interaction with solid targets is tens of times higher than that generated only from the femtosecond laser filament; the maximum EMP signals appeared at a 20°–80°detection angle. The relationship between the energy of EMPs and the width and energy of the laser pulses is presented and discussed. These findings are beneficial for gaining insight into the EMP generation mechanism, spatial distribution, and transmission, and for providing more information for the design of EMPs’ shielding.
Impact of Collaborative Agglomeration of Manufacturing and Producer Services on Air Quality: Evidence from the Emission Reduction of PM2.5, NOx and SO2 in China
Authors: Ye Penghao , Li Jin , Ma Wenjing , Zhang Huarong
Published: June 2022

Industrial agglomeration is a major source of regional economic development and the main pattern enterprises employ after having developed to a certain stage. Industrial agglomeration also affects the emissions of air pollutants in production. Based on provincial panel data for China from 2006 to 2019, this paper introduces the full generalized least squares (FGLS) panel econometrics model. By considering spatial correlation, the potential endogenous problem has been controlled using the instrumental variable and the effects of the co-agglomeration of manufacturing and producer services on three major air pollutants, i.e., SO2, PM2.5, and NOx, have been empirically estimated. The empirical results show that: (1) The agglomeration of manufacturing increases the emission of PM2.5 in the air, while the agglomeration of producer services and the co-agglomeration of manufacturing and producer services reduce it. Moran correlation index test showed that SO2 and NOx had no significant spatial correlation. (2) The agglomeration of manufacturing, the agglomeration of producer services, and co-agglomeration exert the most significant effects on PM2.5 in the air in central and western China. This is probably because of the availability of basic natural resources in these areas. (3) The energy consumption structure mediates the effect of the agglomeration of manufacturing on PM2.5, and human capital mediates the effect of the agglomeration of producer services on PM2.5 emissions. Based on the results, policy suggestions to improve the atmospheric environment during the process of industrial agglomeration are proposed.
Low-Energy Electron Scattering from c-C4F8
Authors: Gupta Dhanoj , Choi Heechol , Kwon Deuk-Chul , Su He , Song Mi-Young , Yoon Jung-Sik , Tennyson Jonathan
Published: June 2022

Electron collision cross-sections of c-C4F8 were investigated at low energies by using the R-matrix method. The static exchange (SE), static exchange with polarization (SEP), and close-coupling (CC) models of the R-matrix method were used for the calculation of the scattering cross-section. The shape resonance was detected with all the models at around 3~4 eV, and a Feshbach resonance was detected with the SEP model at 7.73 eV, in good agreement with the previous theoretical calculation. The resonance detected was also associated with the experimental dissociative electron attachment of c-C4F8, which displayed the resonances at the same energy range. The cross-sections calculated are important for plasma modeling and applications.
Impact of the COVID-19 Lockdown on Patients with Chronic Tinnitus—Preliminary Results
Authors: Fioretti Alessandra , Natalini Eleonora , Triggianese Gianluigi , Eibenstein Rebecca , Angelone Anna Maria , Lauriello Maria , Eibenstein Alberto
Published: June 2022

The COVID-19 pandemic and the lockdown measures are both causes of psychological distress. The aim of the current study was to evaluate the psychological effects of lockdown measures on patients with subjective chronic tinnitus diagnosed before the COVID-19 pandemic. A sample of n = 77 patients with chronic tinnitus was contacted by mail/phone for a survey between June 2021 and September 2021. All patients filled out questionnaires on tinnitus distress (Tinnitus Handicap Inventory, THI), anxiety (Beck Anxiety Inventory, BAI) and depression (Beck Depression Inventory, BDI) and eight items of the Tinnitus Sample Case History (TSCH) about tinnitus history (i.e., loudness, pitch, perception, tinnitus location), stress, and related conditions (noise annoyance, vertigo/dizziness, headache). Forty patients with chronic tinnitus filled out the survey. No significant differences of total THI mean scores (p > 0.05) were found compared to the results obtained before the COVID-19 pandemic and after lockdown. Regarding depression and anxiety, the female population showed a significant increase in scores obtained from the BDI (p < 0.0170) and the BAI (p < 0.049). Only two patients (0.5%) were infected by COVID-19 (positive RT-PCR), and they did not report any worsening of tinnitus. According to the data of the literature, our patients experienced a heterogeneous course of tinnitus, and the severity of tinnitus was not significantly affected by lifestyle changes during the COVID-19 pandemic and lockdown.
A Liquid Metal-Enhanced Wearable Thermoelectric Generator
Authors: Liu Wei , Li Zhenming , Yang Yanfang , Hu Chengbo , Wang Zhen , Lu Yongling
Published: June 2022

It is a key challenge to continuously power personal wearable health monitoring systems. This paper reports a novel liquid metal-enhanced wearable thermoelectric generator (LM-WTEG that directly converts body heat into electricity for powering the wearable sensor system. The gallium-based liquid metal alloys with room-temperature melting point (24~30 °C) and high latent heat density (about 500 MJ/m3) are used to design a new flexible finned heat sink, which not only absorbs the heat through the solid-liquid phase change of the LM and enhances the heat release to the ambient air due to its high thermal conduction. The LM finned is integrated with WTEG to present high biaxial flexibility, which could be tightly in contact with the skin. The LM-WTEG could achieve a super high output power density of 275 μW/cm2 for the simulated heat source (37 °C) with the natural convective heat transfer condition. The energy management unit, the multi-parameter sensors (including temperature, humidity, and accelerometer), and Bluetooth module with a total energy consumption of about 65 μW are designed, which are fully powered from LM-WTEG through harvesting body heat.
Physiological and Pathophysiological Effects of C-Type Natriuretic Peptide on the Heart
Authors: Yasoda Akihiro
Published: June 2022

C-type natriuretic peptide (CNP) is the third member of the natriuretic peptide family. Unlike other members, i.e., atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), which are cardiac hormones secreted from the atrium and ventricle of the heart, respectively, CNP is regarded as an autocrine/paracrine regulator with broad expression in the body. Because of its low expression levels compared to ANP and BNP, early studies failed to show its existence and role in the heart. However, recent studies have revealed the physiological and pathophysiological importance of CNP in the heart; in concert with the distribution of its specific natriuretic peptide receptor-B (NPR-B), CNP has come to be regarded as the major heart-protective natriuretic peptide in the failed heart. NPR-B generates intracellular cyclic guanosine 3′,5′-monophosphate (cGMP) upon CNP binding, followed by various molecular effects including the activation of cGMP-dependent protein kinases, which generates diverse cytoprotective actions in cardiomyocytes, as well as in cardiac fibroblasts. CNP exerts negative inotropic and positive lusitropic responses in both normal and failing heart models. Furthermore, osteocrin, the intrinsic and specific ligand for the clearance receptor for natriuretic peptides, can augment the effects of CNP and may supply a novel therapeutic strategy for cardiac protection.
Functional and Seasonal Changes in the Structure of Microbiome Inhabiting Bottom Sediments of a Pond Intended for Ecological King Carp Farming
Authors: Wolińska Agnieszka , Kruczyńska Anna , Grządziel Jarosław , Gałązka Anna , Marzec-Grządziel Anna , Szałaj Klaudia , Kuźniar Agnieszka
Published: June 2022

The main goal of the study was to determine changes in the bacterial structure in bottom sediments occurring over the seasons of the year and to estimate microbial metabolic activity. Bottom sediments were collected four times in the year (spring, summer, autumn, and winter) from 10 different measurement points in Cardinal Pond (Ślesin, NW Poland). The Next-Generation Sequencing (MiSeq Illumina) and Community-Level Physiological Profiling techniques were used for identification of the bacterial diversity structure and bacterial metabolic and functional activities over the four seasons. It was evident that Proteobacteria, Acidobacteria, and Bacteroidetes were the dominant phyla, while representatives of Betaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria predominated at the class level in the bottom sediments. An impact of the season on biodiversity and metabolic activity was revealed with the emphasis that the environmental conditions in summer modified the studied parameters most strongly. Carboxylic and acetic acids and carbohydrates were metabolized most frequently, whereas aerobic respiration I with the use of cytochrome C was the main pathway used by the microbiome of the studied bottom sediments.