bluuebunny/crossref_metadata_2025 huggingface dataset:
Environmental Enrichment as Part of the Improvement of the Welfare of Japanese Quails
Authors: Ramankevich Anastasiya , Wengerska Karolina , Rokicka Kinga , Drabik Kamil , Kasperek Kornel , Ziemiańska Agnieszka , Batkowska Justyna
Published: August 2022

The aim of this study was to evaluate the indicators of the behavioural and physiological welfare of Japanese quails (Coturnix japonica) as possible responses to the enrichment of the birds’ habitat. The study sample consisted of 280 Japanese quails (224 ♀ and 56 ♂, respectively). Birds of 5 weeks of age were randomly divided into seven equally sized groups and then divided into replication subgroups (four per group, 10 birds in each replication). Birds were maintained in 0.5 m2 cages with unrestricted access to water and food. The experimental factor was the presence or absence of enrichment of the birds’ cages: the nest box, scratcher, plastic corrugated pipe (tunnel), limestone cubes, sandbathing box and feeder box with a drilled cover. Quails were subjected to behavioural tests (tonic immobility and open field tests) and, after 6 weeks, blood samples were taken from them to determine their biochemical indices as well as their cortisol and corticosterone levels. An additional element was the assessment of fertility indices. The presence of enrichment was shown to reduce behavioural disturbances in Japanese quails. This study also found that the colour and shape of an object were very important regarding the birds’ interest in it. Additionally, individuals kept in enriched cages, who were allowed to exhibit their natural behavioural patterns, had lower stress levels.
Shipping Temperature, Time and Media Effects on Equine Wharton’s Jelly and Adipose Tissue Derived Mesenchymal Stromal Cells Characteristics
Authors: Iacono Eleonora , Lanci Aliai , Gugole Penelope , Merlo Barbara
Published: August 2022

To use Mesenchymal Stromal Cells (MSCs) in equine patients, isolation and expansion are performed in a laboratory. Cells are then sent back to the veterinary clinic. The main goal of storage conditions during cell transport is to preserve their biological properties and viability. The aim of this study was to evaluate the effects of storage solutions, temperature and time on the characteristics of equine adipose tissue and Wharton’s jelly-derived MSCs. We compared two different storage solutions (plasma and 0.9% NaCl), two different temperatures (4 °C and room temperature) and three time frames (6, 24, 48 h). Cell viability, colony-forming units, trilineage differentiation, the expression of CD45 and CD90 antigens and adhesion potentials were evaluated. Despite the molecular characterization and differentiation potential were not influenced by storage conditions, viability, colony-forming units and adhesion potential are influenced in different way, depending on MSCs sources. Overall, this study found that, despite equine adipose tissue MSCs being usable after 24 h of storage, cells derived from Wharton’s jelly need to be used within 6 h. Moreover, while for adipose cells the best conservation solutions seems to be plasma, the cell viability of Wharton’s jelly MSCs declined in both saline and plasma solution, confirming their reduced resistance to conservation.
No Evidence of SARS-CoV-2 Infection in Wild Mink (Mustela lutreola and Neogale vison) from Northern Spain during the First Two Years of Pandemic
Authors: Villanueva-Saz Sergio , Giner Jacobo , Palomar Ana María , Gómez María Asunción , Põdra Madis , Aranda María del Carmen , Jiménez María de los Ángeles , Lizarraga Patricia , Hernández Raquel , Portillo Aránzazu , Oteo José Antonio , Ruíz-Arrondo Ignacio , Pérez María Dolores , Tobajas Ana Pilar , Verde Maite , Lacasta Delia , Marteles Diana , Hurtado-Guerrero Ramón , Santiago Llipsy , Ruíz Héctor , Fernández Antonio
Published: August 2022

The impact of the SARS-CoV-2 pandemic on wildlife is largely unevaluated, and extended surveillance of animal species is needed to reach a consensus on the role of animals in the emergence and maintenance of SARS-CoV-2. This infection has been detected in farmed and domestic animals and wild animals, mainly in captivity. The interactions or shared resources with wildlife could represent a potential transmission pathway for the SARS-CoV-2 spill over to other wild species and could lead to health consequences or the establishment of new reservoirs in susceptible hosts. This study evaluated the presence of SARS-CoV-2 in European mink (Mustela lutreola) and American mink (Neogale vison) in Spain by enzyme-linked immunosorbent assay (ELISA) using the receptor binding domain (RBD) of Spike antigen in serum samples and/or by RT-qPCR assays in oropharyngeal and rectal swabs. From January 2020 to February 2022, a total of 162 animals (127 European mink and 35 American mink) with no evidence of SARS-CoV-2 infection were included in the study. Antibodies against the SARS-CoV-2 were not found in the serum samples analysed (n = 126), nor was the virus amplified by RT-qPCR (n = 160 swabs). Our results suggest that the potential role of wild mink and the European mink bred in captivity and released to the wild as dispersers of SARS-CoV-2 is so far low. However, wildlife surveillance for early detection of human and animal risks should be continued. In this sense, epidemiological monitoring measures, including serology and molecular analysis, are necessary.
Signs of Anxiety and Salivary Copeptin Levels in Dogs Diagnosed with Separation-Related Problems in a Short Separation Test
Authors: Pierantoni Ludovica , Albertini Mariangela , Piotti Patrizia , Ripamonti Giulia , Pocar Paola , Borromeo Vitaliano , Pirrone Federica
Published: August 2022

The need for faster diagnosis and more accurate treatment decisions in separation-related problems (SRPs) in dogs is urgent, and a more precise behavioral phenotyping and the development of biomarkers may be of great value. Vasopressin could be a potential non-invasive biomarker of anxiety in dogs with SRPs, but reliable measurement of its concentration is challenging. Here, we compared the behavior and salivary concentrations of copeptin, an arginine vasopressin surrogate, in dogs with SRPs (Case group, n = 13) and with no problems (Control group, n = 15) as they were introduced to a novel environment and subjected to a short episode of separation and reunion with the owner. Dogs in the Case group had greater odds of showing locomotory or oral behaviors during the pre- and post-separation than Controls, while the odds were significantly lower during separation. They also had greater odds of being persistent in seeking attention and proximity from the stranger during reunion. Overall, dogs with SRPs were more likely to express an anxiety-like state during the entire test than Controls, with separation from the owner, and even its anticipation, possibly accounting for this group difference. Although salivary copeptin concentrations did not differ between the two groups, a different trend was detected in Cases and Controls that is worth exploring in further validation studies involving a larger sample.
Risk Factors for Community-Acquired Urinary Tract Infections Caused by Multidrug-Resistant Enterobacterales in Thailand
Authors: Assawatheptawee Kanit , Treebupachatsakul Pornpit , Luangtongkum Taradon , Niumsup Pannika R.
Published: August 2022

The dissemination of multidrug-resistant Enterobacterales (MDRE) in community settings is becoming a great concern. This study aimed to assess the incidence and risk factors associated with community-acquired urinary tract infections (CA-UTIs) caused by MDRE. A prospective case–control study was undertaken among patients with UTIs visiting an outpatient department in Phitsanulok Province, Thailand. Urine samples were collected and screened to include only patients with Enterobacterales infections. Risk factors were analyzed by multivariate logistic regression analysis. Of the 284 patients with CA-UTIs, 25.7% (n = 73) and 74.3% (n = 211) were positive for MDRE (case) and non-MDRE (control), respectively. Being a farmer was identified as an independent risk factor for MDRE-associated CA-UTIs (adjusted odds ratio = 3.101; 95% confidence interval = 1.272–7.564; p = 0.013). A total of 309 Enterobacterales isolates were recovered, and Escherichia coli was the most frequently detected (86.4%). The highest resistance rate was observed for ampicillin (67.0%), followed by ciprofloxacin (34.0%) and cotrimoxazole (32.7%), while resistance to third-generation cephalosporins (cefotaxime, ceftriaxone) and levofloxacin remained <20%. Resistance to ampicillin–gentamicin–cotrimoxazole was the most common pattern among MDRE isolates. Interestingly, we detected a colistin-resistant Enterobacter cloacae harboring mcr-9 (colistin MIC = 16 µg/mL). mcr-9 was transferable at high frequency (4.5 × 10−4) and resided on IncF plasmid. This study demonstrates that being a farmer is a risk factor for MDRE-associated CA-UTIs. Interestingly, this is the first report to identify mcr-9-positive E. cloacae from a Thai patient in the community.
Expansion of the pRAS3 Plasmid Family in Aeromonas salmonicida subsp. salmonicida and Growing Evidence of Interspecies Connections for These Plasmids
Authors: Fournier Kim C. , Paquet Valérie E. , Attéré Sabrina A. , Farley Judith , Marquis Hélène , Gantelet Hubert , Ravaille Christian , Vincent Antony T. , Charette Steve J.
Published: August 2022

Aeromonas salmonicida subsp. salmonicida is a pathogenic bacterium responsible for furunculosis in salmonids. Following an outbreak of furunculosis, the infection can be treated with antibiotics, but it is common to observe ineffective treatment due to antibiotic resistance. This bacterium has a wide variety of plasmids responsible for this resistance. Among them, pRAS3 carries a tetracycline resistance gene. Several variants of this plasmid have been discovered over the years (pRAS3-3432 and pRAS3.1 to 3.4). During the present study, two new variants of the plasmid pRAS3 were identified (pRAS3.5 and pRAS3-3759) in strains of A. salmonicida subsp. salmonicida. Plasmid pRAS3-3759, which has been found in many strains from the same region over the past three years, has an additional genetic element identical to one found in pRAS3-3432. This genetic element was also found in Chlamydia suis, a swine pathogen. In this study, we analyzed the bacteria’s resistance to tetracycline, the number of copies of the plasmids, and the growth of the strains that carry five of the pRAS3 variants (pRAS3.3 to 3.5, pRAS3-3432, and pRAS3-3759). The results show no particular trend despite the differences between the plasmids, except for the resistance to tetracycline when analyzed in an isogenic background. Blast analysis also revealed the presence of pRAS3 plasmids in other bacterial species, which suggests that this plasmid family has widely spread. This study once again highlights the ability of A. salmonicida subsp. salmonicida to adapt to furunculosis antibiotic treatments, and the still-growing family of pRAS3 plasmids.
Targeted Modification and Structure-Activity Study of GL-29, an Analogue of the Antimicrobial Peptide Palustrin-2ISb
Authors: Liu Siyan , Lin Yaxian , Liu Jiachen , Chen Xiaoling , Ma Chengbang , Xi Xinping , Zhou Mei , Chen Tianbao , Burrows James F. , Wang Lei
Published: August 2022

Antimicrobial peptides (AMPs) are considered as promising antimicrobial agents due to their potent bioactivity. Palustrin-2 peptides were previously found to exhibit broad-spectrum antimicrobial activity with low haemolytic activity. Therefore, GL-29 was used as a template for further modification and study. Firstly, the truncated analogue, GL-22, was designed to examine the function of the ‘Rana box’, which was confirmed to have no impact on antimicrobial activity. The results of antimicrobial activity assessment against seven microorganisms demonstrated GL-22 to have a broad-spectrum antimicrobial activity, but weak potency against Candida albicans (C. albicans). These data were similar to those of GL-29, but GL-22 showed much lower haemolysis and lower cytotoxicity against HaCaT cells. Moreover, GL-22 exhibited potent in vivo activity at 4 × MIC against Staphylococcus aureus (S. aureus)-infected larvae. Several short analogues, from the C-terminus and N-terminus of GL-22, were modified to identify the shortest functional motif. However, the results demonstrated that the shorter peptides did not exhibit potent antimicrobial activity, and the factors that affect the bioactive potency of these short analogues need to be further studied.
Pharmacodynamics of Flucloxacillin in a Neutropenic Murine Thigh Infection Model: A Piece of the Puzzle towards Evidence-Based Dosing
Authors: Roelofsen Eveline E. , de Winter Brenda C. M. , van der Spek Heleen , Snijders Susan , Koch Birgit C. P. , van den Berg Sanne , Muller Anouk E.
Published: August 2022

For decades, flucloxacillin has been used to treat methicillin-susceptible Staphylococcus aureus (MSSA). Little is still known about its pharmacodynamics (PD). The present study aimed to determine the pharmacokinetic (PK)/PD index and the PD-index value minimally required for efficacy. MICs of 305 MSSA isolates were measured to determine the wild-type distribution. The PD of 8 S. aureus, 1 S. pyogenes, and 1 S. agalactiae isolates were evaluated in a neutropenic murine thigh infection model. Two S. aureus isolates were used in a dose-fractionation study and a dose–response analysis was performed additionally in the in vivo model. Data were analyzed with a population PK and sigmoid maximum effect model. The end of the wild-type distribution was 1 mg/L. The percentage of time the unbound concentration was above MIC (%fT > MIC) was best correlated with efficacy. For S. aureus, median %fT > 0.25 × MIC required for 1-log reduction was 15%. The value for S. pyogenes was 10%fT > MIC and for S. agalactiae 22%fT > 0.25xMIC for a 1-log reduction. The effect of flucloxacillin reached a 2-log reduction of S. aureus at 20%fT > 0.25xMIC and also for S. pyogenes and S. agalactiae, a reduction was reached. These data may serve to optimize dosing regimens currently used in humans.
A Promising Antifungal and Antiamoebic Effect of Silver Nanorings, a Novel Type of AgNP
Authors: González-Fernández Sara , Lozano-Iturbe Victor , Menéndez Mª Fe , Ordiales Helena , Fernández-Vega Iván , Merayo Jesús , Vazquez Fernando , Quirós Luis M. , Martín Carla
Published: August 2022

Silver nanoparticles (AgNPs) play an important role in the medical field due to their potent antimicrobial activity. This, together with the constant emergence of resistance to antimicrobial drugs, means AgNPs are often investigated as an alternative to solve this problem. In this article, we analyzed the antifungal and antiamoebic effects of a recently described type of AgNP, silver nanorings (AgNRs), and compared them with other types of AgNPs. Tests of the activity of AgNPs against various fungal and amoebic species were carried out. In all cases, AgNPs showed a high biocidal effect, although with fungi this depended on the species involved. Antifungal activity was detected by the conditioning of culture media or water but this effect was not dependent on the release of Ag ions. On the other hand, the proliferation of Acanthamoeba castellanii trophozoites was reduced by silver nanorings (AgNRs) and silver nanowires (AgNWs), with AgNWs being capable of totally inhibiting the germination of A. castellanii cysts. AgNRs constitute a new type of AgNP with an antifungal and antiacanthamoebic activity. These results open the door to new and effective antimicrobial therapies as an alternative to the use of antifungals or antiamoebic drugs, thus avoiding the constant appearance of resistance and the difficulty of eradicating infections.
Antimicrobial Utilization among Neonates and Children: A Multicenter Point Prevalence Study from Leading Children’s Hospitals in Punjab, Pakistan
Authors: Mustafa Zia Ul , Khan Amer Hayat , Salman Muhammad , Syed Sulaiman Syed Azhar , Godman Brian
Published: August 2022

Antimicrobial resistance (AMR) compromises global health due to the associated morbidity, mortality, and costs. The inappropriate use of antimicrobial agents is a prime driver of AMR. Consequently, it is imperative to gain a greater understanding of current utilization patterns especially in high-risk groups including neonates and children. A point prevalence survey (PPS) was conducted among three tertiary care children’s hospitals in the Punjab province using the World Health Organization (WHO) methodology. Antibiotic use was documented according to the WHO AWaRe classification. Out of a total of 1576 neonates and children, 1506 were prescribed antibiotics on the day of the survey (prevalence = 95.5%), with an average of 1.9 antibiotics per patient. The majority of antibiotics were prescribed in the medical ward (75%), followed by surgical ward (12.8%). Furthermore, 56% of antibiotics were prescribed prophylactically, with most of the antibiotics (92.3%) administered via the parenteral route. The top three indications for antibiotics were respiratory tract infections (34.8%), gastrointestinal infections (15.8%), and prophylaxis for medical problems (14.3%). The three most common antibiotics prescribed were ceftriaxone (25.8%), amikacin (9.2%), and vancomycin (7.9%). Overall, 76.6% of the prescribed antibiotics were from Watch category followed by 21.6% from the Access group. There was a very high prevalence of antibiotic use among hospitalized neonates and children in this study. Urgent measures are needed to engage all the stakeholders to formulate effective ASPs in Pakistan, especially surrounding Watch antibiotics.
Exogenously Applied Rohitukine Inhibits Photosynthetic Processes, Growth and Induces Antioxidant Defense System in Arabidopsis thaliana
Authors: Ahmed Sajad , Asgher Mohd , Kumar Amit , Gandhi Sumit G.
Published: August 2022

The secondary metabolite rohitukine has been reported in only a few plant species, including Schumanniophyton magnificum, S. problematicum, Amoora rohituka, Dysoxylum acutangulum and D. gotadhora. It has several biological activities, such as anticancer, anti-inflammatory, antiadipogenic, immunomodulatory, gastroprotective, anti-implantation, antidyslipidemic, anti-arthritic and anti-fertility properties. However, the ecological and physiological roles of rohitukine in parent plants have yet to be explored. Here for the first time, we tried to decipher the physiological effect of rohitukine isolated from D. gotadhora on the model system Arabidopsis thaliana. Application of 0.25 mM and 0.5 mM rohitukine concentrations moderately affected the growth of A. thaliana, whereas a remarkable decrease in growth and the alteration of various morphological, physiological and biochemical mechanisms were observed in plants that received 1.0 mM of rohitukine as compared to the untreated control. A. thaliana showed considerable dose-dependent decreases in leaf area, fresh weight and dry weight when sprayed with 0.25 mM, 0.5 mM and 1.0 mM of rohitukine. Rohitukine exposure resulted in the disruption of photosynthesis, photosystem II (PSII) activity and degradation of chlorophyll content in A. thaliana. It also triggered oxidative stress in visualized tissues through antioxidant enzyme activity and the expression levels of key genes involved in the antioxidant system, such as superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX). Rohitukine-induced changes in levels of metabolites (amino acids, sugars, organic acids, etc.) were also assessed. In light of these results, we discuss (i) the likely ecological importance of rohitukine in parent plants as well as (ii) the comparison of responses to rohitukine treatment in plants and mammals.
Antioxidant, Anti-Proliferative Activity and Chemical Fingerprinting of Centaurea calcitrapa against Breast Cancer Cells and Molecular Docking of Caspase-3
Authors: Aboul-Soud Mourad A. M. , Ennaji Hanane , Kumar Ashok , Alfhili Mohammad A. , Bari Ahmed , Ahamed Maqusood , Chebaibi Mohamed , Bourhia Mohammed , Khallouki Farid , Alghamdi Khalid M. , Giesy John P.
Published: August 2022

Centaurea calcitrapa has been intensively utilized in ethnomedicinal practices as a natural therapeutic recipe to cure various ailments. The current study aimed to chemically characterize ethanolic extract of C. calcitrapa (EECC) aerial parts (leaves and shoots) by use of gas chromatography-mass spectrometry analyses (GC-MS) and investigate its antioxidant and in vitro anticancer activities, elucidating the underlying molecular mechanism by use of flow cytometry-based fluorescence-activated cell sorting (FACS) and conducting in silico assessment of binding inhibitory activities of EECC major compounds docked to caspase-3. CG-MS profiling of EECC identified a total of 26 major flavonoids and polyphenolic compounds. DPPH and ABTS assays revealed that EECC exhibits potent antioxidant activity comparable to standard reducing agents. Results of the proliferation assay revealed that EECC exhibit potent, dose-dependent cytotoxic activities against triple-positive (MCF-7) and triple-negative (MDA-MB-231) breast cancer cell models, with IC50 values of 1.3 × 102 and 8.7 × 101 µg/mL, respectively. The observed cytotoxic effect was specific to studied cancer cells since EECC exhibited minimal (~<10%) cytotoxicity against MCF-12, a normal breast cell line. FACS analysis employing annexin V-FITC/propidium iodide double labeling demonstrated that the observed anti-proliferative activity against MCF-7 and MDA-MB-231 was mediated via apoptotic as well as necrotic signaling transduction processes. The increase in fluorescence intensity associated with DCFH oxidation to DCF, as reported by FACS, indicated that apoptosis is caused by generation of ROS. The use of caspase-3-specific fluorogenic substrate revealed a dose-dependent elevation in caspase-3 substrate-cleavage activity, which further supports EECC-mediated apoptosis in MCF-7 cells. The major EECC compounds were examined for their inhibitory activity against caspase-3 receptor (1HD2) using molecular docking. Three compounds exhibited the highest glide score energy of −5.156, −4.691 and −4.551 kcal/mol, respectively. Phenol, 2,6-dimethoxy established strong binding in caspase-3 receptor of hydrogenic type, with residue ARG 207 and of PI-PI stacking type with residue HIS 121. By contract, hexadecenoic acid showed 3 H-bond with the following residues: ASN 615, ASN 616a and THR 646. Taken together, the current findings reveal that EECC exhibits significant and specific cytotoxicity against breast cancer cells mediated by the generation of ROS and culminating into necrosis and apoptosis. Further investigations of the phytoconstituents-rich C. calcitrapa are therefore warranted against breast as well as other human cancer cell models.
The Microalgal Diatoxanthin Inflects the Cytokine Storm in SARS-CoV-2 Stimulated ACE2 Overexpressing Lung Cells
Authors: Sansone Clementina , Pistelli Luigi , Del Mondo Angelo , Calabrone Luana , Fontana Angelo , Noonan Douglas M. , Albini Adriana , Brunet Christophe
Published: August 2022

Contact between SARS-CoV-2 and human lung cells involves the viral spike protein and the human angiotensin-converting enzyme 2 (ACE2) receptor on epithelial cells, the latter being strongly involved in the regulation of inflammation as well as blood pressure homeostasis. SARS-CoV-2 infection is characterized by a strong inflammatory response defined as a “cytokine storm”. Among recent therapeutic approaches against SARS-CoV-2 targeting the dramatic inflammatory reaction, some natural products are promising. Diatoms are microalgae able to produce bioactive secondary metabolites, such as the xanthophyll diatoxanthin (Dt). The aim of this study is to demonstrate the anti-inflammatory effects of Dt on the A549-hACE2 lung cell line, exploring its interaction with the ACE2 receptor, as well as depicting its role in inhibiting a cytokine storm induced by the SARS-CoV-2 spike glycoprotein. Results showed that Dt enhanced the cell metabolism, e.g., the percent of metabolically active cells, as well as the ACE2 enzymatic activity. Moreover, Dt strongly affected the response of the SARS-CoV-2 spike glycoprotein-exposed A549-hACE2 cells in decreasing the interleukin-6 production and increasing the interleukin-10 release. Moreover, Dt upregulated genes encoding for the interferon pathway related to antiviral defense and enhanced proteins belonging to the innate immunity response. The potential interest of Dt as a new therapeutic agent in the treatment and/or prevention of the severe inflammatory syndrome related to SARS-CoV-2 infection is postulated.
Potential Molecular Targets of Oleanolic Acid in Insulin Resistance and Underlying Oxidative Stress: A Systematic Review
Authors: Fernández-Aparicio Ángel , Correa-Rodríguez María , Castellano Jose M. , Schmidt-RioValle Jacqueline , Perona Javier S. , González-Jiménez Emilio
Published: August 2022

Oleanolic acid (OA) is a natural triterpene widely found in olive leaves that possesses antioxidant, anti-inflammatory, and insulin-sensitizing properties, among others. These OA characteristics could be of special interest in the treatment and prevention of insulin resistance (IR), but greater in-depth knowledge on the pathways involved in these properties is still needed. We aimed to systematically review the effects of OA on the molecular mechanisms and signaling pathways involved in the development of IR and underlying oxidative stress in insulin-resistant animal models or cell lines. The bibliographic search was carried out on PubMed, Web of Science, Scopus, Cochrane, and CINHAL databases between January 2001 and May 2022. The electronic search produced 5034 articles but, after applying the inclusion criteria, 13 animal studies and 3 cell experiments were identified, using SYRCLE’s Risk of Bias for assessing the risk of bias of the animal studies. OA was found to enhance insulin sensitivity and glucose uptake, and was found to suppress the hepatic glucose production, probably by modulating the IRS/PI3K/Akt/FoxO1 signaling pathway and by mitigating oxidative stress through regulating MAPK pathways. Future randomized controlled clinical trials to assess the potential benefit of OA as new therapeutic and preventive strategies for IR are warranted.
Oxidative Stress in Cardiovascular Disease and Comorbidities
Authors: Zalba Guillermo , Moreno María U.
Published: August 2022

Reactive oxygen species (ROS), both as second messengers and as contributors to oxidative stress, play a major, complex role in the initiation, development and outcomes of cardiovascular diseases [...]
Determining the Dynamic Characteristics of a Multi-Story RC Building Located in Chile: A Comparison of the Results between the Nonparametric Spectral Analysis Method and the Parametric Stochastic Subspace Identification Method
Authors: Fuentes Fernando , Lozano Sebastián , Gomez Miguel , Vielma Juan C. , Lopez Alvaro
Published: August 2022

Estimating the dynamic characteristics of instrumented built structures from seismic vibration data collected from built civil structures is essential input information for structural model updating and assessing the health of structures. This study focuses on the earthquake acceleration time histories obtained from several events recorded during its construction phase by accelerometers placed throughout an office building located in Viña del Mar (Chile) to determine its modal features. To this end, the data obtained were analyzed to compare the building’s dynamic properties obtained with two different modal identification techniques. MATLAB programs were developed to implement both methods. The stochastic subspace identification technique for linear systems developed by van Overschee and de Moor was used to study the dynamic properties of the building. In contrast, the nonparametric method employed herein uses correlations and spectral analysis based on the Welch transform in the frequency domain. The investigation demonstrated that both methods identify similar frequencies and that the obtained translational mode shapes exhibit good agreement. Furthermore, the identified frequencies are congruent with the design frequencies.
High-Intensity Low Frequency Pulsed Electromagnetic Fields Treatment Stimulates Fin Regeneration in Adult Zebrafish—A Preliminary Report
Authors: Carnovali Marta , Stefanetti Noemi , Galluzzo Alessandro , Romeo Pietro , Mariotti Massimo , Sansone Valerio
Published: August 2022

Low-Intensity electromagnetic fields (LI-PEMFs) are known to induce a trophic stimulus on bone tissue and therefore have been largely used for the treatment of several musculoskeletal disorders. High intensity (HI) PEMFs add interesting features to bio-stimulation such as electroporation, a phenomenon characterized by transient increased cell permeabilization to molecules, and diamagnetism, a water-repulsive effect based on the diamagnetic properties of water and transmembrane ions gradients. Despite the rapid evolution of technology, the biological mechanisms underlying it are still poorly understood. In order to evaluate the effectiveness of this particular stimulation, HI LF-PEMFs were used to stimulate the caudal fin rays of adult zebrafish. Actually, the zebrafish fin regeneration is a simple, well understood, and widely adopted model for studying bone regeneration. A controlled amputation fin experiment was then conducted. Regenerated bone matrix of fin rays was dyed with calcein and then analysed under fluorescence microscopy. Both the length and the area of regenerated fin’s rays treated with HI LF-PEMFs resulted significantly increased when compared with non-treated.
A New Electro-Optical-Thermal Modelling for Non-Dispersive IR Sensing Technique of Gas Concentration
Authors: Shen Chih-Hsiung , Wu Jung-Jie
Published: August 2022

In this research, a new electro-optical-thermal modeling is proposed and built by simulation program with integrated circuit emphasis (SPICE). In particular, it is constructed for use in the non-dispersive infrared (NDIR) sensing technique of gas concentration. This model, based on the theory of circuitry and the Beer-Lambert law, includes various equivalent elements for the optics, sensor, and circuits. To build and investigate the validity of the proposed model, an NDIR for measurement of CO2 is built with the hybrid combination of a thermopile sensor with a specific wavelength filter, an infrared micro electro mechanical systems (MEMS) heater, an optical tube, amplification circuits with a chopper amplifier, advanced RISC machine (ARM)-based micro processing unit and discrete electronic devices. The thermal properties of the light source with periodic modulation have been studied from the output signal of a thermopile within the limit of modulation frequency. Based on the thorough measurements of output signals and transient responses, the thermal and optical parameters of the sensor and optical components for this model are extracted. The comparison of the simulation and experimental data of the NDIR measurement for different CO2 concentrations shows a great agreement with a maximum error of 0.27% at 3500 ppm. This approach allows for the development of a high-level sensor and circuit integrated simulation based on the most fundamental principles and multiple variables.
Determination of Johnson–Cook Material and Failure Model Constants for High-Tensile-Strength Tendon Steel in Post-Tensioned Concrete Members
Authors: Gkolfinopoulos Ioannis , Chijiwa Nobuhiro
Published: August 2022

The estimation of damage in steel tendons is important for evaluating the remaining capacity of existing tensioned members. This research focuses on calculating Johnson–Cook (LC) model and damage parameters of high-strength steel material through quasi-static and dynamic uniaxial tests. Finite element analysis is used to replicate the experimental procedure, and through dynamic image correlation analysis, the numerical results accuracy is verified. In this investigation, it is found that the JC model can accurately replicate deformation and stress concentration under different strain rates and triaxiality conditions and, thus, can be used for fracture analysis of prestressed concrete members.
Subwavelength Chiral Spiral Acoustic Metamaterials for a Robust Topological Acoustic Insulator
Authors: Yang Tao , Chen Meng , Xiao Boya , Liu Yu , Jiang Heng , Wang Yuren
Published: August 2022

Topological acoustic insulators enable sound waves to transmit along the surface without backscattering, which builds a new pathway towards sound wave control. However, a large share of topological acoustic insulators are realized based on special point group symmetry and Bragg scattering mechanism. This method not only exerts a restriction on the unit cell design but also requires the lattice constant to be comparable with the wavelength. In this paper, the chiral spiral acoustic metamaterials are constructed based on an Archimedean spiral structure. This structure enjoys subwavelength characteristics and is easy to construct. Taking advantage of the chirality of the spiral structure topological phases with opposite energy flow direction can be constructed. The edge state is formed at the interface composed of the spiral units sharing different chirality, which does not depend on point group symmetry. The topological transportation on the interfaces shows strong robustness despite sharp corners verified by straight and zigzag waveguides. The topological acoustic insulator with a chiral spiral structure provides a novel strategy for small acoustic devices with robust sound transmission.
Wavelet Energy Evolution Characteristics of Acoustic Emission Signal under True-Triaxial Loading during the Rockburst Test
Authors: Hu Chuanyu , Mei Fuding , Hussain Wakeel
Published: August 2022

The rockburst simulation test is conducted by utilizing a mineral-containing marble specimen. The loading condition is set to the three directions, each loading on five surfaces except for a single free surface. The whole test procedure is monitored in real time by using a PCI-II acoustic emission monitoring system and a high-speed camera. According to the test outcomes, rockburst is a process in which energy is rapidly released from the free surface. Rock block and rock plate are buckled and ejected from the free surface and a severe rockburst process is accompanied by spray rock powder. An explosion sound can be heard during the process, which can be analyzed by signal processing techniques. The failure mode of the specimen is a splitting-shearing composite failure, and the free surface becomes a rockburst destruction surface. A V-type rockburst pit is formed in the ejection area. The effective acoustic emission signal of the whole test process is decomposed and reconstructed using five-layer wavelets to produce six frequency band sub-signals. In addition, the wavelet energy and its energy distribution coefficients are assessed for various frequency bands, and the proportion of each dominant frequency band within each period is computed. Finally, it was found that the dominant frequency band is 125~250 kHz, while the suboptimal frequency band is 250~500 kHz. The succeeding features are noticed to be used as predicted features for the rockburst disaster. Namely, acoustic emission signals arise in large numbers and the energy distribution coefficient of the dominant frequency band concentrates above 0.4. The proportion of dominant frequency band appears in continuous valley type and keeps below 80%, while the proportion of suboptimal frequency band appears in continuous peak type and keeps above 20%.
A Neural Network-Based Navigation Approach for Autonomous Mobile Robot Systems
Authors: Chen Yiyang , Cheng Chuanxin , Zhang Yueyuan , Li Xinlin , Sun Lining
Published: August 2022

A mobile robot is a futuristic technology that is changing the industry of automobiles as well as boosting the operations of on-demand services and applications. The navigation capability of mobile robots is a crucial task and one of the complex processes that guarantees moving from a starting position to a destination. To prevent any potential incidents or accidents, navigation must focus on the obstacle avoidance issue. This paper considers the navigation scenario of a mobile robot with a finite number of motion types without global environmental information. In addition, appropriate human decisions on motion types were collected in situations involving various obstacle features, and the corresponding environmental information was also recorded with the human decisions to establish a database. Further, an algorithm is proposed to train a neural network model via supervising learning using the collected data to replicate the human decision-making process under the same navigation scenario. The performance of the neural network-based decision-making method was cross-validated using both training and testing data to show an accuracy level close to 90%. In addition, the trained neural network model was installed on a virtual mobile robot within a mobile robot navigation simulator to interact with the environment and to make the decisions, and the results showed the effectiveness and efficacy of the proposed algorithm.
Stable Matching of Users in a Ridesharing Model
Authors: Fajardo-Delgado Daniel , Hernández-Bernal Carlos , Sánchez-Cervantes María Guadalupe , Trejo-Sánchez Joel Antonio , Espinosa-Curiel Ismael Edrein , Molinar-Solis Jesús Ezequiel
Published: August 2022

A ridesharing system is a transport mode where two or more users share the same vehicle and divide the trip’s expenses based on similar routes and itineraries. Popular ridesharing systems, such as Uber, Flinc, and Lyft, define a matching among users based only on the coincidence of routes. However, these systems do not guarantee a stable matching (i.e., a matching in which no user prefers another different from the assigned one). In this work, a new ridesharing system model is proposed, including three types of trips: identical, inclusive, and partial. This model is used to introduce a new algorithm to address the stable matching problem for ridesharing systems. Finally, a set of experimental simulations of the proposed algorithm is conducted. Experimental results show that the proposed algorithm always produces a stable matching.
Prediction of the Equivalent Steering Angle of a Front-Wheel, High-Clearance Paddy Field Management Machine
Authors: Hu Wenwu , Jin Sheng , Zhou Junchi , Yang Junlang , Luo Yahui , Shi Yixin , Sun Chaoran , Jiang Ping
Published: August 2022

To solve the problem of poor steering consistency for each steering wheel of a four-wheel, independent-steering, high-clearance paddy field management machine, given that the true steering angle of the front wheel cannot be directly obtained through the left and right front wheels steering angle value, a BP (Back Propagation) neural network equivalent steering angle prediction method based on signal feature extraction is proposed in this paper, which can be used to obtain the equivalent steering angle of the front wheel. First, the kinematics model of the paddy field management machine was constructed with the prediction of the steering angle of the management machine as the object. The body was set up in two application environments of cement ground and paddy field, two moving speeds (25 cm/s, 50 cm/s) and three preset steering angles (0°, ±10°) to form six motion modes. The steering angle of the front wheel of the body, the three-axis acceleration of the body, and the angular velocity of the z-axis under twelve conditions were collected. Combining the collected data with the actual trajectory data of the differential BeiDou, the feasibility analysis of the equivalent steering angle prediction was carried out. With the aim of determining an appropriate combination of input factors for optimal equivalent steering angle prediction by the BP neural network, we used FFT (Fast Fourier Transform) and power spectrum conversion to extract and analyze the signal features of the airframe attitude data and obtain the frequency characteristics of the peak power point of the power spectrum, respectively. Through a factor combination test, the optimal BP neural network training factors were determined and, finally, we confirmed that the rotation angles of the front wheels and the z-axis angular velocity may be used as effective training factors. In our investigation on the test set, the mean square error of the equivalent steering angle was found to be less than 0.66°, demonstrating that our approach is effective for obtaining the true steering angle of the front wheel.
Factors Influencing Appliance Wearing Time during Orthodontic Treatments: A Literature Review
Authors: Torsello Ferruccio , D’Amico Giorgia , Staderini Edoardo , Marigo Luca , Cordaro Massimo , Castagnola Raffaella
Published: August 2022

This review aims to analyze the multiple factors affecting patients’ level of compliance (how much they wear removable devices/clear aligners) during orthodontic treatments and to investigate the available methods and devices to monitor the appliance wearing time and to improve it. A literature search was conducted on electronic databases (Pubmed, Scopus, and Google Scholar). The results of the present study suggest that compliance indicators may misestimate the intraoral wearing time. Compliance is affected by patient-related factors (age, personality traits, the importance of personal appearance, self-perception of malocclusion), appliance-related factors (visibility, pain/discomfort), and clinician-related factors (trust, clear and complete communication, motivation). The motivation of pre-pubertal patients is mostly external, while adolescents/young adults have intrinsic motivation for orthodontic treatment. Patients’ self-reports tend to overestimate the appliance wearing time. Even if there is a lack of evidence, teledentistry might improve patients’ awareness of being monitored, thus increasing the time for which orthodontic devices are worn. Compliance is a key factor for clear aligner treatments, but high-quality studies focusing on this aspect are missing. Further studies should focus on how to handle the lack of cooperation and how to increase compliance in order to maximize the treatment’s results.
Experimental Study on Bearing Capacity of Compression Members of Space Grid Structures Reinforced by RPC
Authors: Duan Yutong , Lei Honggang , Zhou Yan , Jin Shihong
Published: August 2022

Insufficient bearing capacity of compression bars in space grid structures can significantly reduce the collapse resistance of structures and cause immeasurable losses. Reactive powder concrete (RPC) with high strength, micro-expansion, and good ductility is used to reinforce the compression members of grid structures by infilling steel tubes. Axial compression tests on five types of high-frequency welded pipes with different section sizes and initial stresses were carried out. The results showed that compared to steel tubes alone, the bearing capacity of steel tubes reinforced by RPC could be increased by 75.77 to 218.34%. With a decrease of either the initial stress or confinement coefficient, the contribution of the material reinforcement increased. The failure mode of the specimen after RPC grouting was the same as that of the non-reinforced steel pipe, which was dominated by elastic-plastic buckling. The grouting hole after reinforcement did not fail prior to the instability of the member, which suggests that necessary measures to repair the hole should be taken. Based on the design method of axial compression bearing capacity of concrete-filled steel tubular members in six codes in China and abroad, the test results of this paper and 242 RPC-filled steel tubes were compared and analyzed. Finally, an equation of nominal bearing capacity, which estimates the ultimate bearing capacity of compressive members strengthened by filled RPC in grid structures, was proposed.
Deep Residual Network Combined with Transfer Learning Based Fault Diagnosis for Rolling Bearing
Authors: Zhou Jianmin , Yang Xiaotong , Li Jiahui
Published: August 2022

Fault diagnosis of rolling bearings is significant for mechanical equipment operation and maintenance. Presently, the deep convolutional neural network (CNN) is increasingly used for fault diagnosis of rolling bearings, but CNN has challenges with incomplete training and lengthy training times. This paper proposes a residual network combined with the transfer learning (ResNet-TL) based diagnosis method for rolling bearing, which can preprocess the one-dimensional data of vibration signals into image data. Then, the transfer learning theory in parameter transfer is applied to the training of the network model, and the ResNet34 network is pre-trained and re-trained; the image data are selected to be the inputs of the fault diagnosis model. The experimental validation of the rolling bearing fault dataset collected from the practical bench and Case Western Reserve University shows the superiority of the ResNet34-TL model compared with other classification models.
GF-1 Satellite Imagery Data Service and Application Based on Open Data Cube
Authors: Cao Qianqian , Li Guoqing , Yao Xiaochuang , Jia Tao , Yu Guojiang , Zhang Lianchong , Xu Dan , Zhang Hao , Shan Xiaojun
Published: August 2022

With the application of big data in Earth observation, satellite imagery data are gradually becoming important means of observation for monitoring changes in vegetation, water bodies, and urbanization. Therefore, new satellite imagery data organization and management paradigms are urgently needed to fully mine the useful information from these data and provide new ways to better quantify and serve the sustainable development of resources and the environment. In this paper, a framework for processing and analyzing Chinese GF-1 satellite imagery data was developed using the latest technologies such as Open Data Cube (ODC) grids, Analysis Ready Data (ARD) generation, and space subdivision, which extended the data loading and processing capacities of the ODC grids for Chinese satellite imagery data. Using the proposed framework, we conducted a case study to investigate the spatial and temporal changes in vegetation and water mapping with GF-1 data collected from 2014 to 2021 covering the Miyun Reservoir, Beijing, China. The experimental results showed that the proposed framework had significantly improved temporal and spatial efficiency compared with the traditional scene-based data management approach, thus demonstrating the advantages and potential of the ODC grids as a new data management paradigm.
Special Issue on Advanced Technologies in Lifelong Learning
Authors: Alario-Hoyos Carlos
Published: August 2022

The rapid changes in today’s society, and in the labor market, require workers to undergo constant retraining in order to update and adapt their knowledge and skills throughout their lives [...]
Calibration by Air in Polarization Sensing
Authors: Volkov Sergei N. , Samokhvalov Ignatii V. , Kim Duk-Hyeon
Published: August 2022

Scattered light polarization serves as an indicator and a characteristic of various processes in the atmosphere. The polarization measurements of all scattering matrix elements provide an adequate description of the optical and morphological parameters and orientation of particles in clouds. In this article, we consider the problem of the calibration of matrix polarization lidar (MPL) parameters. Calibration by air is an effective alternative to the technique for correcting optical element parameters and among the calibration parameters of the MPL optical path are the relative transmission coefficient of a two-channel receiver, the angular positions of the transmission axes of the optical elements of the transmitter and receiver units, including the polarizers and wave plates, and the retardance of wave plates. For the first time, the method of calibration by air was partially implemented in the MPL to study Asian dust in the atmosphere. We considered the calibration problem more generally and this was due to the need to calibrate different MPL modifications from stationary to mobile ones. The calibration equations have been derived in terms of instrumental vectors, and the method of their solution by the generalized least squares method has been proposed. The method has been verified on a numerical MPL model and validated using MPL measurements in Daejeon, Republic of Korea.