bluuebunny/crossref_metadata_2025 huggingface dataset:
Tolerance, Adaptation, and Cell Response Elicited by Micromonospora sp. Facing Tellurite Toxicity: A Biological and Physical-Chemical Characterization
Authors: Piacenza Elena , Campora Simona , Carfì Pavia Francesco , Chillura Martino Delia Francesca , Laudicina Vito Armando , Alduina Rosa , Turner Raymond Joseph , Zannoni Davide , Presentato Alessandro
Published: October 2022

The intense use of tellurium (Te) in industrial applications, along with the improper disposal of Te-derivatives, is causing their accumulation in the environment, where oxyanion tellurite (TeO32−) is the most soluble, bioavailable, and toxic Te-species. On the other hand, tellurium is a rare metalloid element whose natural supply will end shortly with possible economic and technological effects. Thus, Te-containing waste represents the source from which Te should be recycled and recovered. Among the explored strategies, the microbial TeO32− biotransformation into less toxic Te-species is the most appropriate concerning the circular economy. Actinomycetes are ideal candidates in environmental biotechnology. However, their exploration in TeO32− biotransformation is scarce due to limited knowledge regarding oxyanion microbial processing. Here, this gap was filled by investigating the cell tolerance, adaptation, and response to TeO32− of a Micromonospora strain isolated from a metal(loid)-rich environment. To this aim, an integrated biological, physical-chemical, and statistical approach combining physiological and biochemical assays with confocal or scanning electron (SEM) microscopy and Fourier-transform infrared spectroscopy in attenuated total reflectance mode (ATR-FTIR) was designed. Micromonospora cells exposed to TeO32− under different physiological states revealed a series of striking cell responses, such as cell morphology changes, extracellular polymeric substance production, cell membrane damages and modifications, oxidative stress burst, protein aggregation and phosphorylation, and superoxide dismutase induction. These results highlight this Micromonospora strain as an asset for biotechnological purposes.
SENP2 Promotes VSMC Phenotypic Switching via Myocardin De-SUMOylation
Authors: Liang Min , Cai Zhaohua , Jiang Yangjing , Huo Huanhuan , Shen Linghong , He Ben
Published: October 2022

Myocardin is a master regulator of smooth muscle cell (SMC) differentiation, which induces the expression of smooth-muscle-specific genes through its direct association with serum response factor (SRF). During the past two decades, significant insights have been obtained regarding the regulatory control of myocardin expression and transcriptional activity at the transcriptional, post-transcriptional, and post-translational levels. However, whether and how SUMOylation plays important roles in modulating myocardin function remain elusive. In this study, we found that myocardin is modified by SUMO-1 at lysine 573, which can be reversibly de-conjugated by SENP2. SUMO-1 modification promotes myocardin protein stability, whereas SENP2 facilitates its proteasome-dependent degradation. Moreover, we found that PIAS4 is the SUMO E3 ligase that enhances the SUMOylation and protein stability of myocardin. Most importantly, we found that SENP2 promotes phenotypic switching of VSMC. We therefore concluded that SENP2 promotes VSMC phenotypic switching via de-SUMOylation of myocardin and regulation of its protein stability.
Serratiopeptidase Affects the Physiology of Pseudomonas aeruginosa Isolates from Cystic Fibrosis Patients
Authors: Artini Marco , Vrenna Gianluca , Trecca Marika , Tuccio Guarna Assanti Vanessa , Fiscarelli Ersilia Vita , Papa Rosanna , Selan Laura
Published: October 2022

Pseudomonas aeruginosa is frequently involved in cystic fibrosis (CF) airway infections. Biofilm, motility, production of toxins and the invasion of host cells are different factors that increase P. aeruginosa’s virulence. The sessile phenotype offers protection to bacterial cells and resistance to antimicrobials and host immune attacks. Motility also contributes to bacterial colonization of surfaces and, consequently, to biofilm formation. Furthermore, the ability to adhere is the prelude for the internalization into lung cells, a common immune evasion mechanism used by most intracellular bacteria, such as P. aeruginosa. In previous studies we evaluated the activity of metalloprotease serratiopeptidase (SPEP) in impairing virulence-related properties in Gram-positive bacteria. This work aimed to investigate SPEP’s effects on different physiological aspects related to the virulence of P. aeruginosa isolated from CF patients, such as biofilm production, pyoverdine and pyocyanin production and invasion in alveolar epithelial cells. Obtained results showed that SPEP was able to impair the attachment to inert surfaces as well as adhesion/invasion of eukaryotic cells. Conversely, SPEP’s effect on pyocyanin and pyoverdine production was strongly strain-dependent, with an increase and/or a decrease of their production. Moreover, SPEP seemed to increase swarming motility and staphylolytic protease production. Our results suggest that a large number of clinical strains should be studied in-depth before drawing definitive conclusions. Why different strains sometimes react in opposing ways to a specific treatment is of great interest and will be the object of future studies. Therefore, SPEP affects P. aeruginosa’s physiology by differently acting on several bacterial factors related to its virulence.
A Test Management System to Support Remote Usability Assessment of Web Applications
Authors: Generosi Andrea , Villafan José Yuri , Giraldi Luca , Ceccacci Silvia , Mengoni Maura
Published: October 2022

Nowadays, web designers are forced to have an even deeper perception of how users approach their products in terms of user experience and usability. Remote Usability Testing (RUT) is the most appropriate tool to assess the usability of web platforms by measuring the level of user attention, satisfaction, and productivity. RUT does not require the physical presence of users and evaluators, but for this very reason makes data collection more difficult. To simplify data collection and analysis and help RUT moderators collect and analyze user’s data in a non-intrusive manner, this research work proposes a low-cost comprehensive framework based on Deep Learning algorithms. The proposed framework, called Miora, employs facial expression recognition, gaze recognition, and analytics algorithms to capture data about other information of interest for in-depth usability analysis, such as interactions with the analyzed software. It uses a comprehensive evaluation methodology to elicit information about usability metrics and presents the results in a series of graphs and statistics so that the moderator can intuitively analyze the different trends related to the KPI used as usability indicators. To demonstrate how the proposed framework could facilitate the collection of large amounts of data and enable moderators to conduct both remote formative and summative tests in a more efficient way than traditional lab-based usability testing, two case studies have been presented: the analysis of an online shop and of a management platform. Obtained results suggest that this framework can be employed in remote usability testing to conduct both formative and summative tests.
A Multidimensional Analysis of Factors Impacting Mobility of Open-Access Multilane Highways
Authors: Khan Jamal Ahmed , Khurshid Muhammad Bilal , Hussain Arshad , Azam Asif
Published: October 2022

Open-access multilane highways have a significant share in the highway network of Pakistan and other developing countries in Asia. These highways have high access density, design inconsistency, and other operational characteristics that differentiate them from partially controlled-access multilane highways. This study identified significant factors affecting the mobility of open-access highways based on road users’ perceptions as well as field observations. An interview-based questionnaire survey from local respondents and an in-service road survey formed the database for the present study. Questionnaire survey results showed that heavy traffic was the most critical mobility influencing factor on open-access multilane highways, followed by road width and condition, whereas the result of multilinear regression revealed that the most significant variable was access density, followed by the flow and pedestrian crossings. However, it was concluded that controlling access density, preventing pedestrian crossings, and improving pavement condition will improve the mobility of open-access multilane highways.
3′-Aminothiocyclohexanespiro-5′-hydantoin and Its Pt(II) Complex—Synthesis, Cytotoxicity and Xanthine Oxidase Inhibitory Activity
Authors: Cherneva Emiliya , Atanasova Mariyana , Šmelcerović Žaklina , Tomović Katarina , Buyukliev Rossen , Šmelcerović Andrija , Bakalova Adriana
Published: October 2022

Herein, we report the synthesis of platinum(II) complex bearing 3′-aminothiocyclohexanespiro-5′-hydantoin as ligand. The complex was characterized by IR, NMR spectral analyses, elemental analyses and density functional theory (DFT) calculations. Cytotoxicity and inhibitory potential on xanthine oxidase (XO) were evaluated by performed docking calculations. The cytotoxic activities of the 3′-aminothiocyclohexanespiro-5′-hydantoin (1), its Pt(II) complex (2), thiocyclohexanespiro-5′-hydantoin (3), and its platinum complex (4) were assessed against HL-60 and MDA-MB-231 cells in comparison with the antiproliferative activity of cisplatin as a referent. The ligands (1 and 3) did not exhibit in vitro antitumor efficacy on either of the human tumor cell lines. Complex 2 showed higher antitumor activity (IC50 = 42.1 ± 2.8 μM on HL-60 and 97.8 ± 7.5 μM against MDA-MB-231 cells) than complex 4 (IC50 = 89.6 ± 2.8 μM on HL-60 and 112.5 ± 4.2 μM in MDA-MB-231 cells). IC50 values of cisplatin as referent were 8.7 ± 2.4 μM on HL-60 and 31.6 ± 5.4 μM on MDA-MB-231 cell lines. The inhibitory activity of ligands and complexes against XO, evaluated in vitro, were compared with allopurinol (IC50 = 1.70 ± 0.51 μM) as standard inhibitor. The platinum(II) complexes (2 and 4) inhibited the activity of XO, with IC50 values 110.33 ± 26.38 μM and 115.45 ± 42.43 μM, respectively, while the ligands 1 and 3 did not show higher degrees of inhibition at concentrations lower than 150 μM. The inhibitory potential against XO might be a possible precedent resulting in improved profile and anticancer properties.
Effects of Three Cultural Practices on Drosophila suzukii (Diptera: Drosophilidae) in Open Blueberry Fields in Florida
Authors: Parkins Albertha J. , Haseeb Muhammad , Liburd Oscar E. , Kanga Lambert H. B.
Published: October 2022

The spotted-wing Drosophila (SWD), Drosophila suzukii, is native species in Southeast Asia. For over a decade, this invasive pest has been globally expanding. The economic losses to soft fruits and stoned fruits in the United States are increasing every year. Presently, the only viable tool to reduce the SWD population is the continued use of broad-spectrum insecticides. Pesticide resistance is appearing in the populations for the SWD. Organic farmers have limited options to control this pest in open fields. The major goal of this study was to develop cost-effective pest management strategies to manage the SWD using three types of mulches (two plant-based and one fabric-based) to reduce fly population and damage in open blueberry fields in north Florida. The study was conducted in two fruiting seasons (2017 and 2018). The study results demonstrated that the fly trap catches in 2017 shortleaf pine needle mulch had much higher populations (about 2.5-fold) of the SWD than all other treatments. In 2018, the numbers were about 1.7-fold more on shortleaf pine needle mulch than on other treatments. The fine texture of the mulch (pine needles) can easily facilitate the emergence of the SWD if the mulch is not thick enough. Although the pine needles covered the soil surface, it may have been too thin and thus allowed the SWD adults to emerge from the soil without much hindrance. In 2018, a higher population of the SWD was recorded from all the mulching practices. However, there were no significant differences in trap catches between all treatments. In general, the fly population is reduced with the use of pine bark and black weed fabric mulches. This is the first study that reports the effects of three mulches in controlling the SWD populations, which could benefit conventional and organic blueberry growers.
Antimicrobial Activity of Apidermin 2 from the Honeybee Apis mellifera
Authors: Kim Bo-Yeon , Kim Yun-Hui , Choi Yong-Soo , Lee Man-Young , Lee Kwang-Sik , Jin Byung-Rae
Published: October 2022

Apidermins (APDs) are known as structural cuticular proteins in insects, but their additional roles are poorly understood. In this study, we characterized the honeybee, Apis mellifera, APD 2 (AmAPD 2), which displays activity suggesting antimicrobial properties. In A. mellifera worker bees, the AmAPD 2 gene is transcribed in the epidermis, hypopharyngeal glands, and fat body, and induced upon microbial ingestion. Particularly in the epidermis of A. mellifera worker bees, the AmAPD 2 gene showed high expression and responded strongly to microbial challenge. Using a recombinant AmAPD 2 peptide, which was produced in baculovirus-infected insect cells, we showed that AmAPD 2 is heat-stable and binds to live bacteria and fungi as well as carbohydrates of microbial cell wall molecules. This binding action ultimately induced structural damage to microbial cell walls, which resulted in microbicidal activity. These findings demonstrate the antimicrobial role of AmAPD 2 in honeybees.
Mosquito Vectors (Diptera: Culicidae) and Mosquito-Borne Diseases in North Africa
Authors: Nebbak Amira , Almeras Lionel , Parola Philippe , Bitam Idir
Published: October 2022

Mosquitoes (Diptera: Culicidae) are of significant public health importance because of their ability to transmit major diseases to humans and animals, and are considered as the world’s most deadly arthropods. In recent decades, climate change and globalization have promoted mosquito-borne diseases’ (MBDs) geographic expansion to new areas, such as North African countries, where some of these MBDs were unusual or even unknown. In this review, we summarize the latest data on mosquito vector species distribution and MBDs affecting both human and animals in North Africa, in order to better understand the risks associated with the introduction of new invasive mosquito species such as Aedes albopictus. Currently, 26 mosquito species confirmed as pathogen vectors occur in North Africa, including Aedes (five species), Culex (eight species), Culiseta (one species) and Anopheles (12 species). These 26 species are involved in the circulation of seven MBDs in North Africa, including two parasitic infections (malaria and filariasis) and five viral infections (WNV, RVF, DENV, SINV and USUV). No bacterial diseases have been reported so far in this area. This review may guide research studies to fill the data gaps, as well as helping with developing effective vector surveillance and controlling strategies by concerned institutions in different involved countries, leading to cooperative and coordinate vector control measures.
Correction: Ivanovitch et al. Growth and Morphogenesis during Early Heart Development in Amniotes. J. Cardiovasc. Dev. Dis. 2017, 4, 20
Authors: Ivanovitch Kenzo , Esteban Isaac , Torres Miguel
Published: October 2022

In the published publication [...]
Certainties and Uncertainties of Cardiac Magnetic Resonance Imaging in Athletes
Authors: Szabo Liliana , Brunetti Giulia , Cipriani Alberto , Juhasz Vencel , Graziano Francesca , Hirschberg Kristof , Dohy Zsofia , Balla Dorottya , Drobni Zsofia , Perazzolo Marra Martina , Corrado Domenico , Merkely Bela , Zorzi Alessandro , Vago Hajnalka
Published: October 2022

Prolonged and intensive exercise induces remodeling of all four cardiac chambers, a physiological process which is coined as the “athlete’s heart”. This cardiac adaptation, however, shows overlapping features with non-ischemic cardiomyopathies, such as dilated, arrhythmogenic and hypertrophic cardiomyopathy, also associated with athlete’s sudden cardiac death. Cardiac magnetic resonance (CMR) is a well-suited, highly reproducible imaging modality that can help differentiate athlete’s heart from cardiomyopathy. CMR allows accurate characterization of the morphology and function of cardiac chambers, providing full coverage of the ventricles. Moreover, it permits an in-depth understanding of the myocardial changes through specific techniques such as mapping or late gadolinium enhancement. In this narrative review, we will focus on the certainties and uncertainties of the role of CMR in sports cardiology. The main aspects of physiological adaptation due to regular and intensive sports activity and the application of CMR in highly trained athletes will be summarized.
Inadvertent Lead Malposition in the Left Heart during Implantation of Cardiac Electric Devices: A Systematic Review
Authors: Spighi Lorenzo , Notaristefano Francesco , Piraccini Silvia , Giuffrè Giuseppe , Barengo Alberto , D’Ammando Matteo , Notaristefano Salvatore , Bagliani Giuseppe , Zingarini Gianluca , Angeli Fabio , Verdecchia Paolo , Cavallini Claudio
Published: October 2022

Background. The inadvertent lead malposition in the left heart (ILMLH) is an under-recognized event, which may complicate the implantation of cardiac electronic devices (CIEDs). Methods. We investigated the clinical conditions associated with ILMLH and the treatment strategies in these patients. We made a systematic review of the literature and identified 132 studies which reported 157 patients with ILMLH. Results. The mean age of patients was 68 years, and 83 were women. ILMLH was diagnosed, on average, 365 days after CIEDs implantation. Coexisting conditions were patent foramen ovale in 29% of patients, arterial puncture in 24%, perforation of the interatrial septum in 20%, atrial septal defect in 16% and perforation of the interventricular septum in 4%. At the time of diagnosis of ILMLH, 46% of patients were asymptomatic, 31% had acute TIA or stroke and 15% had overt heart failure. Overall, 14% of patients were receiving anticoagulants at the time of diagnosis of ILMLH. After diagnosis of ILMLH, percutaneous or surgical lead extraction was carried out in 93 patients (59%), whereas 43 (27%) received anticoagulation. During a mean 9-month follow-up after diagnosis of ILMLH, four patients experienced TIA or stroke (three on oral anticoagulant therapy and one after percutaneous lead extraction). Conclusion. ILMLH is a rare complication, which is usually diagnosed about one year after implantation of CIEDs. An early diagnosis of ILMLH is important. Lead extraction is a safe and effective alternative to anticoagulants.
Application of the Composite Fibers Based on Chitosan and Chitin Nanofibrils in Cosmetology
Authors: Kodolova-Chukhontseva Vera V. , Dresvyanina Elena N. , Nashchekina Yulia A. , Dobrovol’skaya Irina P. , Bystrov Sergei G. , Ivan’kova Elena M. , Yudin Vladimir E. , Morganti Pierfrancesco
Published: October 2022

Chitosan and composite fibers containing chitin nanofibrils have been developed for use in cosmetology. The tensile strength of the chitosan multifilaments is 160.6 ± 19.0 MPa, and of the composite multifilaments containing chitin, nanofibrils are 198.0 ± 18.4 MPa. Chitin nanofibrils introduced into the chitosan solution contribute to the creation of a new spatial arrangement of chitosan chains and their denser packing. The studies carried out by optical, scanning electron, and atomic force microscopy has shown that the serum, consisting of a mixture of lactic acid and sodium lactate, contains extended oriented structures—“liquid filaments”. It has been also shown that a mixture of serum and composite fibers based on chitosan and chitin nanofibrils has mucoadhesive, film-forming properties. The introduction of composite fibers containing chitin nanofibrils into the serum promotes the reinforcing effect of liquid filaments, the lifting effect of the film. The obtained composition can be used in cosmetology as a skin care product.
Protect the Player, Protect the Game: Reflections from Ex-Professional Rugby Union Players on Law Changes, Protective Equipment, and Duty of Care in the Professional Game
Authors: Daly Ed , Blackett Alexander D. , Pearce Alan J. , Ryan Lisa
Published: October 2022

The emphasis of this study was to interview ex-professional male rugby union players (n = 23, mean age 35.5 ± 4.7 years) and discuss concussion management during their careers. In this study, two major themes were identified: (1) the duty of care to professional rugby union players by medical personnel, coaching staff, and owners of professional clubs and (2) the use of protective equipment and law changes to enhance player safety. In total, twenty-three ex-professional rugby union players were interviewed, and the majority (61%) had represented their countries at international test-level rugby. These interviews highlighted the belief that medical teams should be objective, independent entities within a professional rugby club. Furthermore, medical teams should not be in a position of being pressurised by head coaches, members of the coaching team, or club owners regarding return-to-play (RTP) protocols specific to concussion. The interviewees believed that they were pressured by coaches or members of the coaching team to play with concussion or concussive symptoms and other physical injuries. The results indicated that they had manipulated concussion testing themselves or with assistance to pass standard concussion testing protocols. The interviewees indicated that club owners have a duty of care to players even in retirement due to the high incidence of physical and mental injuries endured as a professional rugby player. Most participants indicated that a reduction in match playing time and reducing the amount of time engaged in contact training (workload volume) may assist in reducing concussion incidence. The participants suggested that changes to the current laws of the game or the use of protective equipment did not mitigate against concussion risk in the game of rugby union. The main limitation to the study is that participants had retired in the past ten years, and conditions for players may have changed. This study has highlighted that additional efforts are required by professional clubs to ensure the highest duty of care is delivered to current players and recently retired players.
Abrasive Water Jet Milling as An Efficient Manufacturing Method for Superalloy Gas Turbine Components
Authors: Holmberg Jonas , Wretland Anders , Berglund Johan
Published: October 2022

In order to improve efficiency when manufacturing gas turbine components, alternative machining techniques need to be explored. In this work, abrasive water jet (AWJ) machining by milling has been investigated as an alternative to traditional milling. Various test campaigns have been conducted to show different aspects of using AWJ milling for the machining of superalloys, such as alloy 718. The test campaigns span from studies of individual AWJ-milled tracks, multi-pass tracks, and the machining of larger components and features with complex geometry. In regard to material removal rates, these studies show that AWJ milling is able to compete with traditional semi/finish milling but may not reach as high an MRR as rough milling when machining in alloy 718. However, AWJ milling requires post-processing which decreases the total MRR. It has been shown that a strong advantage with AWJ milling is to manufacture difficult geometries such as narrow radii, holes, or sharp transitions with kept material removal rates and low impact on the surface integrity of the cut surface. Additionally, abrasive water jet machining (AWJM) offers a range of machining possibilities as it can alter between cutting through and milling. The surface integrity of the AWJM surface is also advantageous as it introduces compressive residual stress but may require post-processing to meet similar surface roughness levels as traditional milling and to remove unwanted AWJM particles from the machined surface.
Distributions of Radiocesium and Plutonium in the Korean Seas and North Pacific after the Fukushima Accident, 2011–2014
Authors: Lee Jaeeun , Kim Suk Hyun , Lee Huisu , Lee Hyunmi , Kim Intae
Published: October 2022

The distributions of artificial radionuclides, radiocesium (134Cs and 137Cs) and plutonium isotopes (238Pu and 239+240Pu), in the surface water around the Korean seas (East/Japan Sea and Yellow Sea) in 2011–2012 and in three sections in the North Pacific between 2011 and 2014 were examined. The 137Cs activities in the surface water in the Korean seas in 2011 (immediately after the Fukushima nuclear power plant (NPP) accident on 17 March 2011) were comparable or not significantly different relative to those in 2010 and 2012. However, 134Cs, which had been not detected in the study area before the Fukushima accident (under the detection limit of 0.1 mBq kg−1 level), were detected rapidly in 2011 after the accident (in about 60% of the 72 samples) and gradually disappeared due to their short half-life (t1/2 = 2.06 years) in 2012 (detected in about 16% of the 24 samples). In addition, the highest activities of radiocesium and Pu isotopes appeared locally in some stations of the Korean Strait region (located between Korea and Japan) within 1–2 months immediately after the accident. This suggests that the radioactive nuclides released immediately after the Fukushima accident were significantly introduced through the atmosphere, based on recent studies conducted in neighboring areas. We also showed that the spatial distribution of radiocesium in the North Pacific moved eastward from 2012 to 2014, and we attempted to quantify the residence time of radiocesium (137Cs) in the Korean seas based on the long-term (tens of years scale) temporal trends of 137Cs activity data, which have been collected since the 1960s and 1970s. The estimated retention time of 137Cs in the East/Japan Sea and Yellow Sea were 25 ± 0.6 and 8.0 ± 0.1 years, respectively. These results are expected to be used as a preliminary study for a potential future event of a marine radioactive accident (which, of course, cannot be predicted) and as basic data for predicting the influences of radionuclide releases in the ocean.
Integrating AIS, GIS and E-Chart to Analyze the Shipping Traffic and Marine Accidents at the Kaohsiung Port
Authors: Chou Chien-Chang , Wang Chia-Nan , Hsu Hsien-Pin , Ding Ji-Feng , Tseng Wen-Jui , Yeh Chien-Yi
Published: October 2022

In the past, case study and questionnaire survey methodologies have often been used to analyze the causes of marine accidents. One of the disadvantages of these two methods is that they can only interpret the specific causes of one particular marine accident at a time. They cannot analyze and find the common causes of most marine accidents. Therefore, this study integrates the Automatic Identification System, Geographic Information System, and an e-chart to explore the relationship between environmental factors (wind, wave, tide, and current), locations, and significant common causes of marine accidents. Firstly, an Automatic Identification System is used to collect the traffic flows of vessels entering/exiting the port. The locations of maritime accidents were then plotted on an e-chart, after which we can quickly analyze the locations of marine accidents on the e-chart. Furthermore, environmental data are displayed using Geographic Information System. Subsequently, all data, including traffic flows of vessels, locations of marine accidents, and environmental data, are integrated into the e-chart simultaneously. As a result, the information related to factors affecting the probability of marine accidents could be displayed clearly on the e-chart. Finally, findings and conclusions are given to port authorities to help manage the ship traffic flow and reduce the probability of the occurrence of marine accidents around the port efficiently.
Effects of Tidal Stream Energy Exploitation on Estuarine Circulation and Its Seasonal Variability
Authors: Sánchez Marcos , Fouz David Mateo , López Iván , Carballo Rodrigo , Iglesias Gregorio
Published: October 2022

Residual flows are of major importance in coastal areas, driving environmental processes such as sediment transport or nutrient dispersion. Consequently, in those areas where a large tidal stream energy resource is available, prior to the installation of a tidal farm, it is imperative to assess how energy extraction affects the residual flows and, in particular, upwelling events. In this paper, the potential effects of different configurations of tidal stream farms on the residual circulation and its seasonality are analysed by means of a case study: Ria de Ortigueira, the westernmost of the Galician Rias Altas (NW Spain). For this purpose, a 3D numerical model was implemented and validated against field measurements. Next, a total of eight case studies, including the operation of bottom-fixed and floating converters under typical summer and winter scenarios, considering upwelling favourable winds, were studied. Overall, when a tidal farm operates, regardless of its configuration and the forcings considered, the resulting general residual flow pattern does not experience significant modifications. This pattern is characterized by a 2D circulation in the inner ria and a positive estuarine circulation in the middle and outer ria. The largest modifications of the residual flow are apparent in the vicinities of the plant, with maximum values of about 0.05 ms−1. Outside this area, the alteration is lower than 0.01 ms−1 and virtually negligible at some distance from the farm where upwelling events develop.
Predicting Acoustic Transmission Loss Uncertainty in Ocean Environments with Neural Networks
Authors: Lee Brandon M. , Johnson Jay R. , Dowling David R.
Published: October 2022

Computational predictions of acoustic transmission loss (TL) in ocean environments depend on the relevant environmental characteristics, such as the sound speed field, bathymetry, and seabed properties. When databases are used to obtain estimates of these properties, the resulting predictions of TL are uncertain, and this uncertainty can be quantified via the probability density function (PDF) of TL. A machine learning technique for quickly estimating the PDF of TL using only a single, baseline TL calculation is presented here. The technique shifts the computational burden from present-time Monte-Carlo (MC) TL simulations in the environment of interest to ahead-of-time training of a neural network using equivalent MC TL simulations in hundreds of ocean environments. An environmental uncertainty approach which draws information from global databases is also described and is used to create hundreds of thousands of TL-field examples across 300 unique ocean environments at ranges up to 100 km for source frequencies between 50 and 600 Hz. A subset of the total dataset is used to train and compare neural networks with various architectures and TL-PDF-generation methods. Finally, the remaining dataset examples are used to compare the machine-learning technique’s accuracy and computational effort to that of prior TL-uncertainty-estimation techniques.
Some Peculiarities of Low-Frequency Hydroacoustic Signals Behavior in Tomographic Studies of “Sea-Land-Sea” System
Authors: Budrin Sergey , Dolgikh Grigory , Chupin Vladimir , Dolgikh Stanislav
Published: October 2022

In this paper, we analyzed the results of experimental data processing in the study of regularities of propagation and transformation of low-frequency harmonic signals at the boundary of the “sea−land−sea” system. Harmonic signals at a carrier frequency of 33 Hz were generated by a low-frequency hydroacoustic radiator in Vityaz Bay. Then, they passed along the shelf of decreasing depth, transformed into seismoacoustic signals of the upper layer of the Earth’s crust and the bedrocks of Shultz Cape and excited hydroacoustic signals at the corresponding frequency in the shelf waters in the open part of the Sea of Japan. When processing the experiment results, we obtained the vertical distributions of the pressure field, caused by an acoustic low-frequency signal passing through the upper layer of the Earth’s crust. We presented the distributions of hydroacoustic and seismoacoustic energies. The obtained experimental data were compared with the simulations by the model, developed strictly according to the experiment scheme and the geological structure of the area. In the discussion of the obtained results, we explained a probable mechanism of acoustic energy propagation and the nature of the vertical distributions of the pressure field formation.
Arrhenius Equation-Based Model to Predict Lithium-Ions Batteries’ Performance
Authors: Zeng Liteng , Hu Yuli , Lu Chengyi , Pan Guang , Li Mengjie
Published: October 2022

The accuracy of Peukert’s battery capacity equation may decrease under the conditions of variable current and variable temperatures. Some researchers have previously tried to overcome the lack of C-rate change. However, the dependence of battery capacity on temperature is still not included. In this paper, we mainly studied the capacity reduction effect of batteries under variable temperatures. The proposed method can calculate the battery’s available capacity according to the specific discharge conditions. The experimental method proposed in this paper provides a reasonable test method to generate the required coefficients in order to establish a state of charge prediction model with high accuracy. After establishing the method, we can make a real-time prediction of the available energy of battery including the remaining energy of battery. From the result, we can see that the result is of great precision and the method is valuable.
Longitudinal Vibration Transmission Control of Marine Propulsion Shafting with Friction Damper Integrated into the Thrust Bearing
Authors: Zhang Ganbo , Zhao Yao , Chu Wei
Published: October 2022

Propeller-induced longitudinal vibration resonance in marine propulsion shafting systems causes great harm to the hull structure and is the primary source of shipboard noise. Integrating a friction damper with designed parameters into thrust bearings can prevent these issues. To investigate the performance of the damper-integrated thrust bearing in longitudinal vibration transmission control, an experimental and theoretical study is carried out in a laboratory-assembled test rig, which consists of components similar to the existing marine propulsion system. We developed a prototype of a thrust bearing designed with a friction-damping generation that allows switching from two supporting states, i.e., damper-connected and damper-disconnected states. Furthermore, a nonlinear analysis method for friction dampers is proposed. By this method, the way in which the friction damper changes the dynamic characteristics of the shafting system is analyzed. Based on the test rig, the acceleration frequency response function (AFRF) of the thrust bearing with and without a friction damper is measured. By comparison, the effectiveness of the friction damper is proved. The experimental results show that the friction damper suppresses the shafting longitudinal vibration response in a broadband frequency range and also confirms the stability of the damping effect, which does not change with the shafting rotational speed or static thrust from the propeller.
Research on Multi-Energy Integrated Ship Energy Management System Based on Hierarchical Control Collaborative Optimization Strategy
Authors: Ren Yuanjie , Zhang Lanyong , Shi Peng , Zhang Ziqi
Published: October 2022

The propulsion systems of hybrid electric ship output and load demand have substantial volatility and uncertainty, so a hierarchical collaborative control energy management scheme of the ship propulsion system is proposed in this paper. In a layer of control scheme, the traditional perturbation algorithm is improved. Increasing the oscillation detection mechanism and establishing the dynamic disturbance step length realizes the real-time stability of maximum power point tracking control. In the second-layer control scheme, the power sensitivity factor and voltage and current double closed-loop controller is introduced. By designing a two-layer coordinated control strategy based on the dynamic droop coefficient, the problem of voltage and frequency deviation caused by load switching is solved. In the third-layer control scheme, due to the need of the optimal scheduling function, the multi-objective particle swarm optimization algorithm was improved through three aspects: introducing the mutation factor, improving the speed formula, and re-initializing the strategy. Compared with other algorithms, this algorithm proves its validity in day-ahead optimal scheduling strategy. The superiority of the hierarchical collaborative optimization control schemes proposed was verified, in which power loss was reduced by 39.3%, the overall tracking time was prolonged by 15.4%, and the environmental cost of the diesel generator was reduced by 8.4%. The control strategy solves the problems of the steady-state oscillation stage and deviation from the tracking direction, which can effectively suppress voltage and frequency fluctuations.
Study of Crack Closure Effect of Hull Plate under Low Cycle Fatigue
Authors: Dong Qin , Rong Mengyuan , Xu Geng
Published: October 2022

The crack closure phenomenon significantly influences low cycle fatigue (LCF) crack growth. The crack closure theory deems that a crack can grow only when the applied load is greater than the fatigue crack opening and closing loads. The revised crack closure theory proposed in this paper provides a new understanding of crack growth: It is no longer the range of stress intensity factor ΔK that controls the crack growth rate, but the effective stress intensity factor ΔKeff. Therefore, it is of great importance to study the crack closure phenomenon of LCF. A combination of experiments and the finite element method (FEM) was used to study the effect of overload on the crack closure effect, and the study was carried out using compact tensile (CT) specimens made of AH32 steel. The FEM was used to obtain the stress changes near the crack tip and the opening displacement changes in the crack trailing area after a single tensile overload, to study the intrinsic mechanism of overload on crack closure, and to obtain the LCF crack opening and closing loads by the nodal displacement method. The effect of overload on crack morphology was observed by using high-magnification electron microscopy in combination with testing.
Configuration Analysis of Factors Influencing Port Competitiveness of Hinterland Cities under TOE Framework: Evidence from China
Authors: Huang Zhenyu , Yang Ying , Zhang Fengmei
Published: October 2022

Attention is increasingly being paid to the influence of hinterland cities on port competitiveness, but in-depth research is lacking on the formation conditions and mechanism of hinterland cities’ influence on port competitiveness. Based on the technology–organization–environment (TOE) framework and the characteristics of Chinese government organizational behavior, in this study, we used fuzzy-set qualitative comparative analysis (fsQCA) to conduct a condition configuration analysis of 21 coastal ports and their hinterland cities in China. The findings showed the following: (1) The technology, organization, and environment conditions of hinterland cities cannot provide the necessary conditions for high or low port competitiveness alone: different combinations of these conditions have produced three high and four low port competitiveness configurations. (2) The three configurations of high port competitiveness are the organization–environment, economy–balance, and finance–balance types. Adequate government financial supply, high tertiary industry proportion, good economic development, and market openness are the core conditions required for achieving high port competitiveness. (3) The four configurations of low port competitiveness are finance–facilities–environment, capability–finance–environment, technology–finance–economy, and capability–industry–economy restrictions. Here, low-level innovation capability, inadequate government financial supply, and low tertiary industry proportion are the core conditions leading to low port competitiveness. We revealed the concurrent synergistic effect of the three conditions of technology, organization, and environment in hinterland cities and demonstrated the causal complexity and asymmetry of the impact of hinterland cities on port competitiveness. Our conclusions provide empirical evidence that will aid hinterland cities in formulating differentiated port competitiveness promotion policies according to their own conditions and endowments.
The Impact of the Crude Oil Price on Tankers’ Port-Call Features: Mining the Information in Automatic Identification System
Authors: Mi Jackson Jinhong , Meng Xiangyan , Chen Yanhui , Wang Yicheng
Published: October 2022

Ship navigation technical data contains a lot of information. In this paper, we explore a relationship between the crude oil price and tankers’ port-call features by mining the information recorded in Automatic Identification System (AIS), which extends the application field of ship navigation technical data and aims to help oil shipping enterprises and port enterprises to arrange operation plans in advance. We generate a monthly panel data over the period from 2010 to 2020 of major global ports located in main crude oil exporting countries from AIS data. By using the panel fixed-effect model and binary logit model, our empirical results innovatively present the tanker’s monthly port-call features are influenced by crude oil price fluctuation through four dimensions, that is the tankers’ port-call numbers, the average docking time, total gross tonnage of the docking tankers and the number of different docking tankers. With these variables, we attempt to analyze the relationship between crude oil price fluctuation on tankers’ port-call features. The results of the study are helpful to comprehensively understand the impact mechanism of the crude oil price on the tankers’ port-call features.
Histoplasma capsulatum Activates Hematopoietic Stem Cells and Their Progenitors through a Mechanism Dependent on TLR2, TLR4, and Dectin-1
Authors: Rodríguez-Echeverri Carolina , Gómez Beatriz L. , González Ángel
Published: October 2022

Hematopoietic stem cells (HSCs), a multipotent and self-renewing population responsible for the generation and maintenance of blood cells, have been the subject of numerous investigations due to their therapeutic potential. It has been shown that these cells are able to interact with pathogens through the TLRs that they express on their surface, affecting the hematopoiesis process. However, the interaction between hematopoietic stem and progenitor cells (HSPC) with fungal pathogens such as Histoplasma capsulatum has not been studied. Therefore, the objective of the present study was to determine if the interaction of HSPCs with H. capsulatum yeasts affects the hematopoiesis, activation, or proliferation of these cells. The results indicate that HSPCs are able to adhere to and internalize H. capsulatum yeasts through a mechanism dependent on TLR2, TLR4, and Dectin-1; however, this process does not affect the survival of the fungus, and, on the contrary, such interaction induces a significant increase in the expression of IL-1β, IL-6, IL-10, IL-17, TNF-α, and TGF-β, as well as the immune mediators Arg-1 and iNOS. Moreover, H. capsulatum induces apoptosis and alters HSPC proliferation. These findings suggest that H. capsulatum directly modulates the immune response exerted by HPSC through PRRs, and this interaction could directly affect the process of hematopoiesis, a fact that could explain clinical manifestations such as anemia and pancytopenia in patients with severe histoplasmosis, especially in those with fungal spread to the bone marrow.
Idiosyncratic Risk Volatility: Stock Price Informativeness or Price Error?
Authors: Widianingsih Yuni Pristiwati Noer , Setiawan Doddy
Published: October 2022

Research on idiosyncratic volatility in developing countries, particularly Indonesia, is scant. This study is the first to explain idiosyncratic concepts through an information environment approach and an examination of information asymmetry. This study aims to analyze the phenomenon of idiosyncratic risk in Indonesia, whether it is related to price informativeness or price error, by considering the information environment. We identified the information environment based on the liquidity levels and stock liquidity risk. Our research revealed the relationship between information asymmetry in the information environment and idiosyncratic volatility by using a sample of 499 companies listed on the Indonesia Stock Exchange during the period 2017–2019. One thousand, two hundred and twenty-nine (firm_year) observation data were obtained. The dependent variable was idiosyncratic volatility, and the independent variable used an information environment consisting of stock liquidity, liquidity risk, and information asymmetry. The findings of this study are expected to contribute to the literature on idiosyncratic volatility by showing how it can predict the development of the information environment, and how the latter is a consequence of information asymmetry. Moreover, this study should also complement views that are related to the concept of idiosyncratic volatility equivalent to price errors; this research has been carried out in previous studies.
Volatility Spillover among Japanese Sectors in Response to COVID-19
Authors: Shigemoto Hideto , Morimoto Takayuki
Published: October 2022

This study clarifies how risks spread across economic sectors and indicates the sectors that are the most affected to help investors with asset allocation and to support them in risk management. Although the Japanese stock market is one of the relatively large global stock markets, no studies have explored volatility spillovers among its sectors. Using the forecast error variance decomposition of the vector autoregressive model, this study examines the volatility spillovers among sectors classified on the Tokyo Stock Exchange. Our findings show that the pattern of volatility spillovers across sectors in the Japanese stock market differs between a few years preceding the coronavirus disease 2019 (pre-COVID-19), from 2014 to 2019, and during the COVID-19 period, in 2020. Although the energy resources and bank sectors are risk receivers in the pre-COVID-19 period, these sectors are risk transmitters during the COVID-19 period. We also find that volatility spillovers in the Japanese stock market are mainly driven by negative realized semivariance. These results are useful for asset allocation and risk management.