bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Immuno-Inflammatory Signals in Liver Ischemia-Reperfusion Injury
Authors: Kaltenmeier Christof , Wang Ronghua , Popp Brandon , Geller David , Tohme Samer , Yazdani Hamza O.
Published: July 2022

Ischemia reperfusion injury (IRI) is a major obstacle in liver resection and liver transplantation. The initial step of IRI is mediated through ischemia which promotes the production of reactive oxygen species in Kupffer cells. This furthermore promotes the activation of pro-inflammatory signaling cascades, including tumor necrosis factor-alpha, IL-6, interferon, inducible nitric oxide synthase, TLR9/nuclear-factor kappa B pathway, and the production of damage-associated molecular patterns (DAMPs), such as ATP, histone, high mobility group box 1 (HMGB1), urate, mitochondrial formyl peptides and S100 proteins. With ongoing cell death of hepatocytes during the ischemic phase, DAMPs are built up and released into the circulation upon reperfusion. This promotes a cytokines/chemokine storm that attracts neutrophils and other immune cells to the site of tissue injury. The effect of IRI is further aggravated by the release of cytokines and chemokines, such as epithelial neutrophil activating protein (CXCL5), KC (CXCL1) and MIP-2 (CXCL2), the complement proteins C3a and C5a, mitochondrial-derived formyl peptides, leukotriene B4 and neutrophil extracellular traps (NETs) from migrating neutrophils. These NETs can also activate platelets and form Neutrophil-platelet microthrombi to further worsen ischemia in the liver. In this review we aim to summarize the current knowledge of mediators that promote liver IRI, and we will discuss the role of neutrophils and neutrophil extracellular traps in mediating IRI.
Emergence of Edible Plant-Derived Nanovesicles as Functional Food Components and Nanocarriers for Therapeutics Delivery: Potentials in Human Health and Disease
Authors: Kim Sora Q. , Kim Kee-Hong
Published: July 2022

Extracellular vesicles (EVs) are a highly heterogeneous population of membranous particles that are secreted by almost all types of cells across different domains of life, including plants. In recent years, studies on plant-derived nanovesicles (PDNVs) showed that they could modulate metabolic reactions of the recipient cells, affecting (patho)physiology with health benefits in a trans-kingdom manner. In addition to its bioactivity, PDNV has advantages over conventional nanocarriers, making its application promising for therapeutics delivery. Here, we discuss the characteristics of PDNV and highlight up-to-date pre-clinical and clinical evidence, focusing on therapeutic application.
Integrin Signaling Shaping BTK-Inhibitor Resistance
Authors: Polcik Laura , Dannewitz Prosseda Svenja , Pozzo Federico , Zucchetto Antonella , Gattei Valter , Hartmann Tanja Nicole
Published: July 2022

Integrins are adhesion molecules that function as anchors in retaining tumor cells in supportive tissues and facilitating metastasis. Beta1 integrins are known to contribute to cell adhesion-mediated drug resistance in cancer. Very late antigen-4 (VLA-4), a CD49d/CD29 heterodimer, is a beta1 integrin implicated in therapy resistance in both solid tumors and haematological malignancies such as chronic lymphocytic leukemia (CLL). A complex inside-out signaling mechanism activates VLA-4, which might include several therapeutic targets for CLL. Treatment regimens for this disease have recently shifted towards novel agents targeting BCR signaling. Bruton’s tyrosine kinase (BTK) is a component of B cell receptor signaling and BTK inhibitors such as ibrutinib are highly successful; however, their limitations include indefinite drug administration, the development of therapy resistance, and toxicities. VLA-4 might be activated independently of BTK, resulting in an ongoing interaction of CD49d-expressing leukemic cells with their surrounding tissue, which may reduce the success of therapy with BTK inhibitors and increases the need for alternative therapies. In this context, we discuss the inside-out signaling cascade culminating in VLA-4 activation, consider the advantages and disadvantages of BTK inhibitors in CLL and elucidate the mechanisms behind cell adhesion-mediated drug resistance.
Spectrophotometric Determination of Formation Constants of Iron(III) Complexes with Several Ligands
Authors: Segoviano-Garfias José J. N. , Zanor Gabriela A. , Ávila-Ramos Fidel , Bivián-Castro Egla Yareth , Rubio-Jiménez Carlos A.
Published: July 2022

Dye-sensitized solar cells transform solar light into electricity. One commonly used dye is a ruthenium complex. However, the use of ruthenium has been shown to have several disadvantages. In this study, via singular spectrum analysis using HypSpec software, we determined the formation constants and calculated individual electronic spectra of species of iron(III) with several ligands (1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 2,2′-bipyridyl, 5,5-dimethyl-2,2′-bipyridyl, 4,4′-di-tert-butyl-2,2′-bipyridyl, 1,10-phenanthroline, and 3,4,7,8-tetramethyl-1,10-phenanthroline) in methanol solution. We present a spectral comparison of the complexes reported here to the ruthenium complex: tris-(2,2′-bipyridyl)ruthenium(II).
Associations between Fundamental Movement Skills, Physical Fitness, Motor Competency, Physical Activity, and Executive Functions in Pre-School Age Children: A Systematic Review
Authors: Malambo Chipo , Nová Aneta , Clark Cain , Musálek Martin
Published: July 2022

Previous empirical research and reviews have suggested that the level of fundamental movement skills (FMS), motor competence (MC), physical activity (PA), or physical fitness seem to directly influence the executive functions (EFs) in school aged children. However, there is no available comprehensive review of whether the exact links between motor constructs and EFs also exist in the preschool period, even though preschool age is the critical period for developing EFs. Therefore, this study aimed to systematically review the evidence on the association between FMS, MC, PA, PF, and EFs. To conduct the systematic review, we utilized searches using Web of Science, PubMed, and EBSCO (including SPORTDiscus and Academic Search Premier). We included studies that examined associations between one or all of the four motor constructs with EFs among typically developing children aged 3–6 years, published between January 2010 and October 2021. A total of 15 studies met the inclusion criteria, of which four were randomized controlled trials, three were longitudinal studies, four were cohort studies, and four were cross-sectional studies. We found weak correlations or insufficient evidence for associations between FMS, PA, PF, and EFs. However, there was strong evidence for a moderately strong association between MC and working memory, a moderately weak association between MC and inhibition, and inadequate evidence for a weak to moderate association between MC and shifting. In addition, only half of the included studies were methodologically high-quality studies. Specifically, a questionable design selection of research samples might bias the strength of evaluated associations. We also found significant diversity in the diagnostic tools used for assessing and measuring motor and EFs domains. Our findings support the assumption that motor competencies level, which contains physical capacity and cognitive components, could be significantly linked to EF development from a preschool age. Therefore, we suggest that future studies focus more on clinical trial design, combining movement interventions with different levels of cognitive components, for the purposive development of EFs in preschool-aged children.
Parametric Mapping Cardiac Magnetic Resonance Imaging for the Diagnosis of Myocarditis in Children in the Era of COVID-19 and MIS-C
Authors: Das Bibhuti B. , Akam-Venkata Jyothsna , Abdulkarim Mubeena , Hussain Tarique
Published: July 2022

Myocarditis comprises many clinical presentations ranging from asymptomatic to sudden cardiac death. The history, physical examination, cardiac biomarkers, inflammatory markers, and electrocardiogram are usually helpful in the initial assessment of suspected acute myocarditis. Echocardiography is the primary tool to detect ventricular wall motion abnormalities, pericardial effusion, valvular regurgitation, and impaired function. The advancement of cardiac magnetic resonance (CMR) imaging has been helpful in clinical practice for diagnosing myocarditis. A recent Scientific Statement by the American Heart Association suggested CMR as a confirmatory test to diagnose acute myocarditis in children. However, standard CMR parametric mapping parameters for diagnosing myocarditis are unavailable in pediatric patients for consistency and reliability in the interpretation. The present review highlights the unmet clinical needs for standard CMR parametric criteria for diagnosing acute and chronic myocarditis in children and differentiating dilated chronic myocarditis phenotype from idiopathic dilated cardiomyopathy. Of particular relevance to today’s practice, we also assess the potential and limitations of CMR to diagnose acute myocarditis in children exposed to severe acute respiratory syndrome coronavirus-2 infections. The latter section will discuss the multi-inflammatory syndrome in children (MIS-C) and mRNA coronavirus disease 19 vaccine-associated myocarditis.
Nurses’ Perceptions of the Quality of Procedural Sedation in Children Comparing Different Pharmacological Regimens
Authors: Curatola Antonietta , D’Agostin Martina , Favaretto Elena , Vittori Giada , Vidonis Viviana , Strajn Tamara , De Vita Nicole , Saccari Alessia , Barbi Egidio , Cortellazzo Wiel Luisa
Published: July 2022

Nurses play a pivotal role during pediatric procedural sedation and their perspective is an important indicator for the quality of care. The aim of this study is to examine nurses’ satisfaction comparing four different pharmacological regimens used for pediatric sedation outside of the operating room. A prospective observational study was conducted in a third-level pediatric teaching hospital, involving all the nurses with experience in the field of pediatric procedural sedation. A 13-item survey was used to assess the level of nurses’ satisfaction for the quality of sedation with four different analgesic–sedative drugs. Fifty-one questionnaires were completed by pediatric nurses, with a median length of experience of 10 years. Regarding the overall quality of the sedation, the highest median satisfaction scores were observed for propofol (8, IQR 7–9), dexmedetomidine (8, IQR 6–8) and midazolam (8, IQR 7–9). Ketamine (5, IQR 3–7) displayed the lowest score. When asked to rate their level of perceived safety, nurses gave high scores to all the four drugs studied, with no statistically significant difference between them. Non-pharmacological techniques during procedural sedation were judged as important by 38 (74.5%) nurses. According to this sample of pediatric nurses, the best quality of procedural sedation in children outside of the operating room is obtained with propofol, dexmedetomidine and midazolam. During procedural sedation, nurses feel safe overall, regardless of the pharmacological regimen used. Moreover, they highlighted the relevance on non-pharmacological approaches in the preparation of the child for the procedure.
Craniofacial Morphologic Predictors for Passive Myofunctional Therapy of Pediatric Obstructive Sleep Apnea Using an Oral Appliance with a Tongue Bead
Authors: Hwang Yi-Jing , Huang Yu-Shu , Lian Yun-Chia , Lee Yu-Hsuan , Hervy-Auboiron Michele , Li Chung-Hsing , Lin Cheng-Hui , Chuang Li-Chuan
Published: July 2022

We conducted this retrospective study to identify potential clinical, polysomnographic, and cephalometric predictors for the treatment outcomes of a tongue-beaded oral appliance (OA) in children with obstructive sleep apnea syndrome (OSAS). In total, 63 patients—50 boys and 13 girls ranging in age from 4 to 16 years—underwent OA treatment nightly for at least 6 months. A baseline digital lateral cephalometric radiograph was obtained for each patient. Multivariate logistic regression analysis was performed to examine predictors for the treatment outcome based on the clinical and cephalometric measurements. Overall, 28 patients responded to the treatment (post-treatment improvement > 50% or apnea–hypopnea index (AHI) < 1/h), and 35 did not (post-treatment improvement < 50% and AHI ≥ 1/h). Significantly larger cranial base angle (SNBa), smaller lower gonial angle (LGo Angle), and shorter length of anterior cranial base (SN) were found in responders. Smaller lower gonial angle (LGo Angle) and smaller anterior cranial base (SN) predict a favorable outcome for pediatric OSAS using a tongue-beaded OA. This finding will equip practitioners with additional insights when selecting suitable candidates for OA therapy in pediatric patients.
Oxygen Availability and Corrosion Propagation in RC Structures in the Marine Environment—Inferences from Field and Laboratory Studies
Authors: Moore Amy , Beushausen Hans , Otieno Mike , Ndawula Joanitta , Alexander Mark
Published: July 2022

The splash and spray and tidal zones are generally assumed to be the most severe marine exposure environments with respect to steel reinforcement corrosion in concrete structures. However, it has been observed in several aged marine structures along the Southern African coastlines, that there is usually relatively insignificant reinforcement corrosion damage in the tidal zone, despite very high (above-threshold) chloride contents. To develop a full understanding of the severity of marine exposure conditions with regard to the actual deterioration, it is imperative that other factors that directly affect corrosion, such as oxygen availability at the steel surface (which is influenced by concrete quality, cover thickness and moisture condition), are carefully considered. The laboratory experimental work in the study presented in this paper comprised of different cover depths (10, 20 and 30 mm) and w/b ratios (0.5 and 0.8) and simulated marine tidal, splash and submerged environments. The results show that for any give exposure environment, the relative influence of each of the various factors considered should be considered in conjunction with the other factors; this finding can be generalized to include all relevant factors that can affect corrosion in a given exposure environment including ambient temperature. For example, a cover depth of 30 mm in the tidal zone with a simulated intertidal duration of 6 h effectively resulted in similar corrosion behavior to that in the submerged zone. The paper concludes that engineers should consider these factors when applying standard exposure classes in the design for durability of marine structures.
Design Methodology and Application of Surface Texture: A Review
Authors: Nsilani Kouediatouka Ange , Ma Qiang , Liu Qi , Mawignon Fagla Jules , Rafique Faisal , Dong Guangneng
Published: July 2022

Surface texture is regarded as a promising solution for enhancing the tribological features of industrial materials due to its outstanding benefits, such as minimization of the contact area, enhancement of the load bearing capacity, storage of the lubricant, and management of the transition between lubrication regimes. Surface texture can be processed under either liquid or gas conditions. As compared to laser ablation in air, employing liquids or other gases as ablation media provides high accuracy and uniformity by limiting the heat-affected zone (HAZ) and other undesired defects to a large extent, as well as high crater structural features. In addition, the synergistic use of different liquid, solid, and additive lubricants with surface roughness recently demonstrated excellent performance. Therefore, surface texture helps to improve the tribological characteristics of a material. This paper reviews the design methodologies and applications of surface texture, emphasizing the proper selection of the appropriate laser parameters and ambient conditions for the best texture quality and functionality. Recent texture geometric design features to improve the film thickness and the self-lubricating system are presented. The ablation environment is explored using various media. The interaction between the lubricants’ types and surface textures is explored based on the operating conditions. Furthermore, surface texture applications using superhydrophobic surfaces, anti-drag, and vibration and noise friction are discussed. We hope that this review plays an enlightening role in follow-up research on laser surface texture.
Dielectric Properties of Plasma-Sprayed Fully Natural Garnets
Authors: Ctibor Pavel , Sedláček Josef , Straka Libor
Published: July 2022

Various kinds of natural garnets belonging to the almandine type (3FeO·Al2O3·3SiO2) were sprayed by plasma spray technique to build coatings on metallic substrates. The experimental garnet powders came from different mines in the Czech Republic and Mongolia. After coating and cooling the substrates were removed. In this way, self-supporting plates were obtained and further studied with microscopy, X-ray diffraction, and dielectric spectroscopy. Mechanical properties were in our focus as well. Microhardness was measured on cross sections dedicated to microstructure observation. Wear resistance in wet conditions was tested in a slurry. Reflectance was measured applying visible and infrared (VIS-NIR) radiation. Dielectric properties of coatings were studied at low voltage capacitance, loss tangent and also under direct current (DC) resistance. The results show that garnet minerals are interesting candidates for various optical and electronic applications; they have similar dielectric behavior as, for example, aluminum oxide or similar high-purity synthetic oxides, and, simultaneously, they have extraordinarily low reflectance in VIS-NIR radiation. The differences between natural powders and resulting coatings are discussed in connection with their chemical and phase compositions.
Effect of Annealing on the Structure of Composite Passivation Films Prepared by Magnetron Sputtering Deposition on the Surface of HgCdTe
Authors: Lin Yang , Qin Qiang , Wang Xiangqian , Chen Jiyuan , Li Lu , Jiang Jun , He Yuanhuai , Wang Xiao , Zhao Peng , Yuan Shouzhang
Published: July 2022

In this study, the structural evolution of the CdTe/ZnS composite passivation films on the surface of infrared HgCdTe material before and after annealing was comparatively explored. The surface morphology and microstructure of the passive films before and after annealing were characterized by scanning electron microscope, X-ray diffraction, atomic force microscopy, and Raman and X-ray photoelectron spectroscopy to determine the effects of the annealing process on the surface crystal defects of the films. The results show that annealing at 320 °C for three hours can improve crystal quality, ameliorate the surface density, and reduce the dislocation density of grains, while the Hg grains inhibited by tellurium-rich growth during the annealing process return to the normal growth state, and the S signal can be detected near the surface after annealing. This finding indicates that high-temperature annealing promotes the inhibited grain growth and also causes diffusion of surface elements, thus smoothing the compositional gradient at the passivation interface of the films.
Trapping Capability of Small Vacancy Clusters in the α-Zr Doped with Alloying Elements: A First-Principles Study
Authors: Pan Rongjian , Tang Aitao , Qin Jiantao , Xin Tianyuan , Wu Xiaoyong , Wen Bang , Wu Lu
Published: July 2022

Zirconium alloys are subjected to a fast neutron flux in nuclear reactors, inducing the creation of a large number of point defects, both vacancy and self-interstitial. These point defects then diffuse and can be trapped by their different sinks or can cluster to form larger defects, such as vacancy and interstitial clusters. In this work, the trapping capability of small-vacancy clusters (two/three vacancies, V2/V3) in the α-Zr doped with alloying elements (Sn, Fe, Cr, and Nb) has been investigated by first-principle calculations. Calculation results show that for the supercells of α-Zr containing 142-zirconium atoms with the two-vacancy cluster, alloying elements of Sn and Nb in the second vacant site (V2) and Cr in the first vacant site (V1) are more easily trapped by two vacancies, respectively. However, the two sites are both captured more easily by two vacancies for Fe in the supercells of α-Zr containing 142-zirconium atoms inside due to the similar value of the Fermi level. For the supercells of α-Zr containing 141-zirconium atoms with the three-vacancy cluster, the alloying element of Sn in the third vacant site (V’3), Fe in the first vacant site (V’1), and Cr and Nb in the second vacant site (V’2) are more easily trapped by three vacancies, respectively.
Is There a Difference in Facial Emotion Recognition after Stroke with vs. without Central Facial Paresis?
Authors: Kuttenreich Anna-Maria , von Piekartz Harry , Heim Stefan
Published: July 2022

The Facial Feedback Hypothesis (FFH) states that facial emotion recognition is based on the imitation of facial emotional expressions and the processing of physiological feedback. In the light of limited and contradictory evidence, this hypothesis is still being debated. Therefore, in the present study, emotion recognition was tested in patients with central facial paresis after stroke. Performance in facial vs. auditory emotion recognition was assessed in patients with vs. without facial paresis. The accuracy of objective facial emotion recognition was significantly lower in patients with vs. without facial paresis and also in comparison to healthy controls. Moreover, for patients with facial paresis, the accuracy measure for facial emotion recognition was significantly worse than that for auditory emotion recognition. Finally, in patients with facial paresis, the subjective judgements of their own facial emotion recognition abilities differed strongly from their objective performances. This pattern of results demonstrates a specific deficit in facial emotion recognition in central facial paresis and thus provides support for the FFH and points out certain effects of stroke.
Elastography in the Urological Practice: Urinary and Male Genital Tract, Prostate Excluded—Review
Authors: Simon Vasile , Dudea Sorin , Crisan Nicolae , Stanca Vasile , Dudea-Simon Marina , Andras Iulia , Mihaly Zoltan , Coman Ioan
Published: July 2022

The aim of this article is to review the utility of elastography in the day-to-day clinical practice of the urologist. An electronic database search was performed on PubMed and Cochrane Library with a date range between January 2000 and December 2021. The search yielded 94 articles that passed the inclusion and exclusion criteria. The articles were reviewed and discussed by organ, pathology and according to the physical principle underlying the elastographic method. Elastography was used in the study of normal organs, tumoral masses, chronic upper and lower urinary tract obstructive diseases, dysfunctions of the lower urinary tract and the male reproductive system, and as a pre- and post-treatment monitoring tool. Elastography has numerous applications in urology, but due to a lack of standardization in the methodology and equipment, further studies are required.
Melanoma Detection by AFM Indentation of Histological Specimens
Authors: Jeon Byoungjun , Jung Hyo Gi , Lee Sang Won , Lee Gyudo , Shim Jung Hee , Kim Mi Ok , Kim Byung Jun , Kim Sang-Hyon , Lee Hyungbeen , Lee Sang Woo , Yoon Dae Sung , Jo Seong Jin , Choi Tae Hyun , Lee Wonseok
Published: July 2022

Melanoma is visible unlike other types of cancer, but it is still challenging to diagnose correctly because of the difficulty in distinguishing between benign nevus and melanoma. We conducted a robust investigation of melanoma, identifying considerable differences in local elastic properties between nevus and melanoma tissues by using atomic force microscopy (AFM) indentation of histological specimens. Specifically, the histograms of the elastic modulus of melanoma displayed multimodal Gaussian distributions, exhibiting heterogeneous mechanical properties, in contrast with the unimodal distributions of elastic modulus in the benign nevus. We identified this notable signature was consistent regardless of blotch incidence by sex, age, anatomical site (e.g., thigh, calf, arm, eyelid, and cheek), or cancer stage (I, IV, and V). In addition, we found that the non-linearity of the force-distance curves for melanoma is increased compared to benign nevus. We believe that AFM indentation of histological specimens may technically complement conventional histopathological analysis for earlier and more precise melanoma detection.
Correction: Christensen et al. Impact of [18F]FDG-PET and [18F]FLT-PET-Parameters in Patients with Suspected Relapse of Irradiated Lung Cancer. Diagnostics 2021, 11, 279
Authors: Christensen Tine N. , Langer Seppo W. , Persson Gitte , Larsen Klaus Richter , Amtoft Annemarie G. , Keller Sune H. , Kjaer Andreas , Fischer Barbara Malene
Published: July 2022

In the original publication [...]
Oblique View Selection for Efficient and Accurate Building Reconstruction in Rural Areas Using Large-Scale UAV Images
Authors: Liang Yubin , Fan Xiaochang , Yang Yang , Li Deqian , Cui Tiejun
Published: July 2022

3D building models are widely used in many applications. The traditional image-based 3D reconstruction pipeline without using semantic information is inefficient for building reconstruction in rural areas. An oblique view selection methodology for efficient and accurate building reconstruction in rural areas is proposed in this paper. A Mask R-CNN model is trained using satellite datasets and used to detect building instances in nadir UAV images. Then, the detected building instances and UAV images are directly georeferenced. The georeferenced building instances are used to select oblique images that cover buildings by using nearest neighbours search. Finally, precise match pairs are generated from the selected oblique images and nadir images using their georeferenced principal points. The proposed methodology is tested on a dataset containing 9775 UAV images. A total of 4441 oblique images covering 99.4% of all the buildings in the survey area are automatically selected. Experimental results show that the average precision and recall of the oblique view selection are 0.90 and 0.88, respectively. The percentage of robustly matched oblique-oblique and oblique-nadir image pairs are above 94% and 84.0%, respectively. The proposed methodology is evaluated for sparse and dense reconstruction. Experimental results show that the sparse reconstruction based on the proposed methodology reduces 68.9% of the data processing time, and it is comparably accurate and complete. Experimental results also show high consistency between the dense point clouds of buildings reconstructed by the traditional pipeline and the pipeline based on the proposed methodology.
The Emotional Competence Assessment Questionnaire (ECAQ) for Children Aged from 3 to 5 Years: Validity and Reliability Evidence
Authors: Bartroli Montse , Angulo-Brunet Ariadna , Bosque-Prous Marina , Clotas Catrina , Espelt Albert
Published: July 2022

In order to assess emotional competence in children, it is necessary to have psychometrically sound measures. To the best of our knowledge, there is no available tool to assess emotional competence in children from 3 to 5 years old that assesses the five emotional competences of the Bisquerra model and can be easily and quickly answered in the school environment. The objective of this study is to develop a measure, the Emotional Competence Assessment Questionnaire (ECAQ), and to provide evidence of its psychometric quality. Qualitative evidence was obtained from a systematic review, from two expert committees and from five discussion groups. On the other hand, quantitative validity and reliability evidence was obtained from a sample of 1088 students and other smaller subsamples. The results suggest that the ECAQ is a short and easy-to-use tool, easily understood by administrators. The quantitative results confirm a general factor of emotional competence adjusted for three specific factors. This factor has excellent internal consistency and test-retest reliability. The ECAQ has therefore been shown to be a promising tool for assessing emotional competence in children between 3 and 5 years of age.
Online Mathematics Education during the COVID-19 Pandemic: Didactic Strategies, Educational Resources, and Educational Contexts
Authors: Videla Ronnie , Rossel Sebastián , Muñoz Coralina , Aguayo Claudio
Published: July 2022

One of the impacts of the COVID-19 pandemic has been restrictions on mobility and thus the closure of schools. This has had consequences on the teaching strategies of primary mathematics educators who were not familiar with online education. Most schools in Chile have adopted virtual and hybrid classes to continue educational processes. From a quantitative approach with a sample of n = 105 primary school educators and through an online survey, we analyzed how educators implemented the mathematics curriculum during the pandemic using various didactic strategies and educational resources, as well as their respective contexts. The results show that there is a relationship between the level of technical knowledge of teachers, the years of experience, and the types of teaching strategies they use. Likewise, differences were found between educators in rural and urban sectors according to the use of teaching strategies and the types of educational resources used. Regarding the didactic strategies, it is shown that the emerging strategies most used are metaphorical and analogical, whereas in traditional strategies the automation of procedures is imposed. The implications for practice include suggestions and guidelines for improving the training and professional development of mathematics teachers including increasing and strengthening the number and quality of teachers’ didactic strategies and online pedagogical management skills and promoting metacognition through virtual forums. Finally, we discuss the context of the use of didactic strategies in mathematics during the pandemic, analyzing its challenges and opportunities.
Pulsar Candidate Recognition Using Deep Neural Network Model
Authors: Yin Qian , Wang Yan , Zheng Xin , Zhang Jikai
Published: July 2022

With an improvement in the performance of radio telescopes, the number of pulsar candidates has increased rapidly, which makes selecting valuable pulsar signals from the candidates challenging. It is imperative to improve the recognition efficiency of pulsars. Therefore, we solved this problem from the perspective of intelligent image processing and a deep neural network model AR_Net was proposed in this paper. A single time–phase-subgraph or frequency-phase-subgraph was used as the judgment basis in the recognition model. The convolution blocks can be obtained by combining the attention mechanism module, feature extractor and residual connection. Then, different convolution blocks were superimposed to constitute the AR_Net to screen pulsars. The attention mechanism module was used to calculate the weight through an additional feedforward neural network and the important features in the sample were identified by weight, so the ability of the model to learn pivotal information was improved. The feature extractor was used to gain the high-dimensional features in the samples and the residual connection was introduced to alleviate the problem of network degradation and intensify feature reuse. The experimental results show that AR_Net has higher F1-score, recall and accuracy, and our method produces a competitive result compared with previous methods.
Gate-Width Optimisation Based on Time-Gated Single Photon Avalanche Diode Receiver for Optical Wireless Communications
Authors: Mu Yu , Du Xiaoxiao , Wang Chao , Ye Ziwei , Zhu Yijun
Published: July 2022

Using a single photon avalanche diode (SPAD) as a receiver in an optical wireless communications (OWC) system can effectively expand the transmission distance. However, the performance of the SPAD receiver is usually affected with the bit error rate (BER) lower bound determined by background light and the inter-symbol interference (ISI) distortion caused by dead time. In this paper, external time-gated technology is employed, and the SPAD is only activated within the set gate-ON time to alleviate the influence of background light and ISI distortion. The SPAD photon counting model and the communication BER model are established according to the external time-gated characteristics. Considering the functional relationship among the gate-ON time, signal light flux, background light flux and blocking time, we take the minimum BER as the optimization target, the optimal gate-ON time is derived. The numerical results show that whenever the signal light flux or the background light flux is higher, the BER performance of the time-gated mode is apparently better than the free-running mode. For example, when signal photons and background photons are 30 and 10 per symbol time, respectively, the BER of free-running SPAD converges to 0.1, while the BER of the time-gated scheme is about 10−6.
Lightweight Architecture for Elliptic Curve Scalar Multiplication over Prime Field
Authors: Hao Yue , Zhong Shun’an , Ma Mingzhi , Jiang Rongkun , Huang Shihan , Zhang Jingqi , Wang Weijiang
Published: July 2022

In this paper, we present a novel lightweight elliptic curve scalar multiplication architecture for random Weierstrass curves over prime field Fp. The elliptic curve scalar multiplication is executed in Jacobian coordinates based on the Montgomery ladder algorithm with (X,Y)-only common Z coordinate arithmetic. At the finite field operation level, the adder-based modular multiplier and modular divider are optimized by the pre-calculation method to reduce the critical path while maintaining low resource consumption. At the group operation level, the point addition and point doubling methods in (X,Y)-only common Z coordinate arithmetic are modified to improve computation parallelism. A compact scheduling method is presented to improve the architecture’s performance, which includes appropriate scheduling of finite field operations and specific register connections. Compared with existing works, our design is implemented on the FPGA platform without using DSPs or BRAMs for higher portability. It utilizes 6.4~6.5k slices in Kintex-7, Virtex-7, and ZYNQ FPGA and executes an elliptic curve scalar multiplication for a field size of 256-bit in 1.73 ms, 1.70 ms, and 1.80 ms, respectively. Additionally, our design is resistant to timing attacks, simple power analysis attacks, and safe-error attacks. This architecture outperforms most state-of-the-art lightweight designs in terms of area-time products.
Combustion Performance and Emission Characteristics of Marine Engine Burning with Different Biodiesel
Authors: Yang Ning , Deng Xiaowen , Liu Bin , Li Liwei , Li Yuan , Li Peng , Tang Miao , Wu Lin
Published: July 2022

Ship emissions are one of the main sources of air pollution in port cities. The prosperous maritime trade has brought great harm to the air quality of port cities while promoting the development of the world economy. During the berthing process, ship auxiliary machines emit a large amount of air pollutants, which have a great impact on air quality and public health. Alternative marine fuels are being studied and used frequently to reduce ship emissions. This research was carried out to investigate the gaseous and particles emission characteristics of a marine diesel engine during the application of experimental biodiesel fuels. To study the influence of mixed fuels on engine performance, measurements were made at different engine loads and speeds. Different diesel fuels were tested using various ratios between biodiesel and BD0 (ultra-low sulfur diesel) of 0%, 10%, 30%, 50%, 70%, 90%, and 100%. The results indicated the use of biodiesel has little influence on the combustion performance but has a certain impact on exhaust emissions. The octane number and laminar flame speed of biodiesel are higher than those of BD0, so the combustion time of the test diesel engine is shortened under the mixed mode of biodiesel. In addition, a high ratio of biodiesel leads to a decrease of the instantaneous peak heat release rate, causing the crank angle to advance. As the biodiesel blending ratio increased, most of the gaseous pollutants decreased, especially for CO, but it led to an increase of particle numbers. The particle size distribution exhibits a unimodal distribution under various conditions, with the peak value appearing at 30–75 nm. The use of biodiesel has no effect on this phenomenon. The peak positions strongly depend on fuel types and engine conditions. The particulate matter (PM) emitted from the test engine included large amounts of organic carbon (OC), which accounted for between 30% and 40% of PM. Whereas the elemental carbon (EC) accounted for between 10% and 20%, the water-soluble ions components accounted for 6–15%. Elemental components, which accounted for 3–8% of PM emissions, mainly consisted of Si, Fe, Sn, Ba, Al, Zn, V, and Ni. Generally, biodiesel could be a reliable alternative fuel to reduce ship auxiliary engine emissions at berth and improve port air quality.
Macro- and Microplastics in the Antarctic Environment: Ongoing Assessment and Perspectives
Authors: Rota Emilia , Bergami Elisa , Corsi Ilaria , Bargagli Roberto
Published: July 2022

The number of scientists and tourists visiting Antarctica is on the rise and, despite the management framework for environmental protection, some coastal areas, particularly in the Antarctic Peninsula region, are affected by plastic contamination. The few data available on the occurrence of microplastics (<5 mm) are difficult to compare, due to the different methodologies used in monitoring studies. However, indications are emerging to guide future research and to implement environmental protocols. In the surface and subsurface waters of the Southern Ocean, plastic debris >300 µm appears to be scarce and far less abundant than paint chips released from research vessels. Yet, near some coastal scientific stations, the fragmentation and degradation of larger plastic items, as well as microbeads and microfibers released into wastewater from personal care products and laundry, could potentially affect marine organisms. Some studies indicate that, through long-range atmospheric transport, plastic fibers produced on other continents can be deposited in Antarctica. Drifting plastic debris can also cross the Polar Front, with the potential to carry alien fouling organisms into the Southern Ocean. Sea ice dynamics appear to favor the uptake of microplastics by ice algae and Antarctic krill, the key species in the Antarctic marine food web. Euphausia superba apparently has the ability to fragment and expel ingested plastic particles at the nanoscale. However, most Antarctic organisms are endemic species, with unique ecophysiological adaptations to extreme environmental conditions and are likely highly sensitive to cumulative stresses caused by climate change, microplastics and other anthropogenic disturbances. Although there is limited evidence to date that micro- and nanoplastics have direct biological effects, our review aims at raising awareness of the problem and, in order to assess the real potential impact of microplastics in Antarctica, underlines the urgency to fill the methodological gaps for their detection in all environmental matrices, and to equip scientific stations and ships with adequate wastewater treatment plants to reduce the release of microfibers.
Variation of Selected Macrostructure Features and Density Wood of the European Spruce (Picea abies (L.) Karst.) in the Cross-Section of Trees over 90-Years-Old in Poland
Authors: Michalec Krzysztof , Wąsik Radosław
Published: July 2022

In the present study, the following features were investigated: the variability of selected macrostructure features (width of the annual growth ring and share of latewood) and wood density of the European spruce (Picea abies (L.) Karst.) in a cross-section of the trunk. The study was conducted in locations of the northeastern range (12 research plots) and the southwestern range (20 research plots) of spruce in Poland. On the testing plots, Pressler drill borehole samples were taken from 15 selected trees. Then, the borehole samples were divided into 2 cm long sections and, for each section, the average width of the annual growth ring, the average share of latewood, and the relative wood density were calculated. In conclusion, it was found that the width of the annual growth rings in the tested material was increasing constantly from the outer circumference (the perimeter) of the trunk towards the pith. The greatest share of latewood was found not only in the perimeter zones of the tree trunk but also in the zones close to the pith. It was also discovered that the highest wood densities occur in the perimeter zones, and that these densities decrease towards the pith. It was only in the sections next to the pith that an increase in wood density was noted. Having analysed the relationships between the examined features, it can be concluded that the width of annual growth rings affects both the share of latewood and the wood density. The aforementioned were negative correlations, whereas the increase in the share of latewood also impacts the increase in wood density and was determined to have a positive correlation.
Evaluation and Identification of Key Economic Bottlenecks for Cost-Effective Microbial Oil Production from Fruit and Vegetable Residues
Authors: Gallego-García María , Susmozas Ana , Moreno Antonio D. , Negro María José
Published: July 2022

Intensive horticultural systems for the production of vegetables in greenhouses represent one of the main industries generating organic waste, as those that do not meet the quality standards for the fresh market or the processing industry are discarded. This highlights the importance of using these residues as raw material for other applications, such as bioenergy and bioproducts production, within the framework of a bio-based economy that maximizes the utilization of biomass resources in a sustainable manner. In this work, the microbial oil production from discarded pepper using the oleaginous yeast Cryptococcus curvatus was evaluated. Overall, a total lipid accumulation of 16.8 g/L was achieved with a fatty acid profile suitable to produce biodiesel. The lipid yield obtained was 0.12 g/g sugars. In addition, experimental results were used to assess the techno-economic feasibility of a proposed microbial oil plant using the software Aspen Plus. This plant yields approximately 96 kg of microbial oils/ton dry discarded pepper, with an estimated Minimum Selling Price of 7 €·kg−1. These figures point out the necessity of increasing the yield of microbial oil production and considering the utilization of possible by-products, such as mannitol and cell debris, to improve the economic performance of the process.
Microbiota and Mycobiota of Soy Sauce-Supplied Lactic Acid Bacteria Treated with High Pressure
Authors: Lai Chiung-Yu , Hou Chih-Yao , Chuang Pei-Ting , Hsu Wei-Hsuan , Wu She-Ching
Published: July 2022

Background: Ethyl carbamate (EC), a byproduct that naturally forms in fermented foods, can cause tumors and cell death and is classified as a probable human carcinogen (Group 2A). EC is naturally formed through the alcoholysis reaction between ethanol and carbamyl compounds. The major precursors and dominantly emerging stages of EC differ with disparate food types, including soy sauce. This work aimed to clarify the formation of EC and its influence factors throughout the soy sauce production process with or without high-pressure process (HPP) treatment. Methods: Tetragenococcus halophilus, Pediococcus acidilactici, Zygosaccharomyces rouxii, and Candida versatilis were added to soy sauce. The levels of citrulline and EC were measured, and a 16S and ITS assay investigated the microbiota. Results: L-citrulline production was found in each group after fermentation for one month. In addition, L-citrulline levels were generated the most in group D (500 MPa treated raw soy sauce with 12% saltwater and mixed fermentation bacteria, including T. halophilus,P. acidilactici,Z. rouxii, and C. versatilis) and group E (soy sauce fermentation with 12% saltwater without HPP treatment) compared to group F (soy sauce fermentation with 18% saltwater without HPP treatment). Conclusions: These results indicated that salt concentration and mixed fermentation bacteria (T. halophilus,P. acidilactici,Z. rouxii,C. versatilis) might not be major factors for L-citrulline production.
Otolith Microchemistry Assessment: Evidence of Migratory Coilia nasus of Yangtze River Living in the Shengsi Sea Area
Authors: Li Yu , Chen Jianhua , Feng Guangpeng , Yang Jian , Zhao Feng , Shen Chenchen , Song Chao , Jiang Tao
Published: July 2022

At present, the resources of anadromous fish in the world are drastically reduced and one of the solutions to promote its recovery may be to identify and protect its feeding grounds. To determine whether the feeding grounds of anadromous Coilia nasus in the Yangtze River are still in the sea area, the quantitative line analysis of Sr and Ca contents (Sr/Ca ratios) and the area distribution analysis of Sr content in the otoliths of C. nasus in three water areas (Poyang Lake, Yangtze River estuary and Shengsi Sea area) were carried out by electron probe microanalysis (EPMA) to analyze the habitat use and the migratory patterns of different estuarine C. nasus. These results showed that the Sr/Ca ratios of all otoliths fluctuated significantly. By comparison, it was found that C. nasus of Yangtze River might exist in the Shengsi Sea area, and the Shengsi Sea area might be one of the feeding grounds of migratory C. nasus. Therefore, it is urgent to carry out a comprehensive investigation on the distribution of related groups in the Shengsi Sea area and the influence of potential threat factors, such as fishing and harsh habitat, to effectively protect the resources and habitats of C. nasus in the Shengsi Sea area.
Molecular Characterization and Expression Analysis of TAK1, TAB1 and TAB2 of Golden Pompano (Trachinotus ovatus)
Authors: Xie Yushuai , Lei Kun , He Jinquan , Wei Youchuan
Published: July 2022

Transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1), TAK1-binding protein 1 (TAB1) and TAB2 are components of the mitogen-activated protein kinase (MAPK) pathway. In this study, TAK1, TAB1 and TAB2 were characterized from golden pompano (Trachinotus ovatus), a marine fish of great economic value, and named as trTAK1, trTAB1 and trTAB2, respectively. The lengths of the cDNA sequences of the three genes were 2429 bp, 2068 bp and 4229 bp and encoded 575, 506 and 759 amino acids, respectively. The trTAK1, trTAB1 and trTAB2 genes shared high sequence identities and were well clustered with their counterparts from other fish species. Real-time qPCR analysis showed that the three genes were constitutively expressed in all the selected tissues of healthy pompano, and the expression levels of the three genes were significantly up-regulated in head kidney and spleen following Vibrio alginolyticus, lipolysaccharide (LPS) and polyinosinic polycytidylic acid (poly I:C) challenge, indicating their roles in the immune response against pathogens in golden pompano. Our results provide a basis for further study of the functions of these genes in golden pompano.