bluuebunny/crossref_metadata_2025 huggingface dataset:
Multidimensional Typology of Mexican Farmers in the Context of Climate Change
Authors: Maldonado-Méndez María de Lourdes , Romo-Lozano José Luis , Baca del Moral Julio , Monterroso-Rivas Alejandro Ismael
Published: July 2022

Mexico has a wide range of biophysical and socioeconomic conditions that result in farmers with highly diverse traits and activities in relation to their livelihoods. The aim of this research was to identify specific traits of Mexican farmers that would allow them to be classified through a multidimensional approach that includes the risk of production in the face of exposure and vulnerability to climate change. The method included three dimensions: producer sensitivity, production destination, and exposure to climate change. Principal component analysis combined with the Dalenius and Hodges optimal stratification technique was used to stratify the universe of agricultural producers. The results show that up to 227 groups of agricultural producers can be identified in Mexico, and it was possible to classify them into 19 types, ranging from agricultural producers at greatest risk due to the adverse effects of climate change to agricultural producers with fewer difficulties to produce in conditions of climate change. This proposed multidimensional typology of agricultural producers can become an essential input for designing, reorienting, or focusing public policies in the agricultural sector and moving towards fulfilling the commitments declared in the INDC-2030.
Instance-Aware Plant Disease Detection by Utilizing Saliency Map and Self-Supervised Pre-Training
Authors: Kim Taejoo , Kim Hyeongjun , Baik Kyeonghoon , Choi Yukyung
Published: July 2022

Plant disease detection is essential for optimizing agricultural productivity and crop quality. With the recent advent of deep learning and large-scale plant disease datasets, many studies have shown high performance of supervised learning-based plant disease detectors. However, these studies still have limitations due to two aspects. First, labeling cost and class imbalance problems remain challenging in supervised learning-based methods. Second, plant disease datasets are either unstructured or weakly-unstructured and the shapes of leaves and diseased areas on them are variable, rendering plant disease detection even more challenging. To overcome these limitations, we propose an instance-aware unsupervised plant disease detector, which leverages normalizing flows, a visual saliency map and positional encodings. A novel way to explicitly combine these methods is the proposed model, in which the focus is on reducing background noise. In addition, to better fit the model to the plant disease detection domain and to enhance feature representation, a feature extractor is pre-trained in a self-supervised learning manner using only unlabeled data. In our extensive experiments, it is shown that the proposed approach achieves state-of-the-art performance on widely-used datasets, such as BRACOL (Weakly-unstructured) and PlantVillage (Unstructured), regardless of whether the dataset is weakly-structured or unstructured.
Textile Physical Barriers against the Chestnut Gall Wasp Dryocosmus kuriphilus
Authors: Álvarez Antonio J. , Oliva Rocío M.
Published: July 2022

Dryocosmus kuriphilus Yasumatsu is a species originating from China that, during the 20th century, has spread rapidly throughout many countries, affecting mainly different species of the genus Castanea spp. In fact, it is considered to be the most important pest of chestnut trees (Castanea sativa Miller), causing significant production losses. The adoption of complementary measures to chemical and biological controls would contribute to the control of the pest. In this sense, the use of textile physical barriers could prevent the rapid spread of this species among the production centers. Therefore, the objective of this study is to define the characteristics of a textile that protects young plants that have been produced in nurseries. For this purpose, some commercial textiles have been selected based on the morphometric characterization of the species and these textiles have been accurately measured in order to compare their dimensions with those of the insects. Finally, tests have been carried out in order to measure the efficacy of the textiles under laboratory conditions, controlling the air velocity and the temperature. The results reveal that, in general, theoretical efficacy may not be a good predictor of practical results. A fully effective screen has been found against this species and its design characteristics can be used as a starting point for new, more optimized designs.
Rice Momilactones and Phenolics: Expression of Relevant Biosynthetic Genes in Response to UV and Chilling Stresses
Authors: Hoang Anh La , Van Quan Nguyen , Quang Lam Vu , Takami Akiyoshi , Dang Khanh Tran , Dang Xuan Tran
Published: July 2022

Momilactones A (MA) and B (MB) are known as phytoalexins which principally play a role in the rice defense system against pathogens. This is the first study revealing that MA and MB contribute to rice tolerance to environmental stresses, including ultraviolet (UV) radiation and chilling conditions. The proofs were achieved by scrutinizing the responses of rice under stresses through the expression of relevant biosynthetic genes to momilactones (MRBG) and phenolics (PRBG) and their accumulation. Accordingly, the expression tendency of PRBG was in line with that of MRBGs, which increased under UV irradiation but decreased under chilling conditions. In UV-exposed rice, the proliferation of MA and MB strongly correlated to that of salicylic and chlorogenic acids, esculetin, rutin, and fisetin. In terms of increasing chilling duration, the biosynthetic propensity of MB was consistent with that of benzoic, cinnamic, ρ-coumaric, salicylic, and syringic acids, quercetin, and tricin while the syntheses of MA and other compounds were reduced. The concomitant biosyntheses of momilactones with these acknowledged stress-resistant phenolics imply that momilactones might play a role as signaling molecules in the response mechanism of rice to UV and chilling stresses. Further comprehensive studies should be conducted to validate this paradigmatic finding.
DEM-MBD Coupling Simulation and Analysis of the Working Process of Soil and Tuber Separation of a Potato Combine Harvester
Authors: Li Yuyao , Hu Zhichao , Gu Fengwei , Wang Bing , Fan Jiali , Yang Hongguang , Wu Feng
Published: July 2022

To address the competing relationship between tuber damage and soil removal in potato combine harvesting, this study investigated the operating mechanism of a belt-rod type separator of a small-scale self-propelled potato combine harvester and the separation performance between tuber and soil. The main factors affecting the tuber-soil separation characteristics were derived from a theoretical analysis of the belt-rod angle, belt-rod linear velocity, and harvester forward speed. A simulation model based on DEM (Discrete Element Method)-MBD (Multibody Dynamics) coupling was constructed and single-factor simulation tests were carried out. Then a three-factor, three-level Box–Behnken test was conducted using the coefficient of force on the tuber and soil clearing rate as response indicators. The optimal combination of parameters resulting in low tuber damage and high soil clearing rate was obtained by solving the regression equations. The optimal parameters were a belt-rod angle of 17.5°, a belt-rod linear velocity of 1.37 m/s, and a harvester forward speed of 0.80 m/s. The simulation model was validated by field experiments and the error between the simulation model and the field harvest was found to be 3.81%. The results can be used as a reference for parameter optimization of small-scale potato combine harvesters and coupled DEM-MBD simulation of tuber-soil separation.
Germplasm Innovation and Establishment of Comprehensive Evaluation System for Hedgerow Garden Chrysanthemum
Authors: Zhao Yong , Huo Bingjie , Lin Sisi , Zhang Shuangshuang , Mao Chenyuan , Jiang Jiafu , Chen Sumei , Fang Weimin , Guan Zhiyong , Liao Yuan , Wang Zhenxing , Chen Fadi , Wang Haibin
Published: July 2022

Garden chrysanthemums are a group of chrysanthemums (Chrysanthemum morifolium) that are mostly used in garden landscape collocations. Because most garden chrysanthemum varieties have low plants and poor space effects, they have certain limitations in garden landscape applications. In this study, we selected seven garden chrysanthemum varieties with excellent characteristics for artificial hybridization and intercross parentage to obtain new varieties with good traits we need. The phenotypic characteristics of the F1 offspring in terms of plant height, crown width, crown height ratio, number of main branches, branching intensity, plant form, inflorescence diameter, number of flowers per plant, number of ray florets, flower color, and days from planting period to coloring period were analyzed and systematically evaluated. Subsequently, a comprehensive evaluation system was established using the analytic hierarchy process (AHP) and k-means clustering method. We built a comprehensive analysis model, calculated the weighting of each evaluation factor, and multiplied the weight value by the score of the evaluation index standard of each factor to obtain the comprehensive score of each plant. All F1 plants were divided into four grades: excellent grade accounting for 13%, good grade accounting for 28%, medium grade accounting for 36%, and poor grade accounting for 23%. Then, we analyzed the differences of some quantitative traits between Group E (hybrids in excellent grade) and Group O (hybrids in good, medium, and poor grades). There were significant differences in plant height, crown height ratio, and the number of main branches but no significant difference in crown width. Combining with comprehensive score showed that Group E performed well overall. Finally, we selected five hybrid offspring with the highest overall scores in Group E as excellent variety materials of garden chrysanthemum for hedgerow. They were CH22, YQ73, HY08, CQ80, and HY07, respectively. We also found that plant height, lodging resistance, crown height ratio, plant form, crown width, and the number of main branches could be the main indicators in the AHP, which can be effectively applied to the comprehensive evaluation and breeding of garden chrysanthemums for hedgerows.
Performance Comparison of Machine Learning Algorithms in Classifying Information Technologies Incident Tickets
Authors: Oliveira Domingos F. , Nogueira Afonso S. , Brito Miguel A.
Published: July 2022

Technological problems related to everyday work elements are real, and IT professionals can solve them. However, when they encounter a problem, they must go to a platform where they can detail the category and textual description of the incident so that the support agent understands. However, not all employees are rigorous and accurate in describing an incident, and there is often a category that is totally out of line with the textual description of the ticket, making the deduction of the solution by the professional more time-consuming. In this project, a solution is proposed that aims to assign a category to new incident tickets through their classification, using Text Mining, PLN and ML techniques, to try to reduce human intervention in the classification of tickets as much as possible, reducing the time spent in their perception and resolution. The results were entirely satisfactory and allowed to us determine which are the best textual processing procedures to be carried out, subsequently achieving, in most of the classification models, an accuracy higher than 90%, making its implementation legitimate.
Retrospective Comparison of the Effectiveness and Safety of Ceftriaxone 1 g Twice Daily versus 2 g Once Daily for Treatment of Aspiration Pneumonia
Authors: Kato Hideo , Hagihara Mao , Morikawa Yoshihiko , Asai Nobuhiro , Mikamo Hiroshige , Iwamoto Takuya
Published: July 2022

Although a 2 g once daily administration of ceftriaxone remains the standard dosing regimen for the treatment of aspiration pneumonia, there are no studies to investigate the optimal dosing method. Hence, we retrospectively evaluated the effectiveness and safety of 1 g twice daily versus 2 g once daily administration of ceftriaxone in adult patients with aspiration pneumonia. Patients who received ceftriaxone for the treatment of aspiration pneumonia between 2015 and 2021 were included in this study. Clinical responses, inflammatory markers, and incidence of adverse events after completion of ceftriaxone therapy were investigated. In total, 33 patients received 1 g twice daily (group 1) and 28 received 2 g once daily (group 2) ceftriaxone for the treatment of mild-to-moderate aspiration pneumonia. Compared with that of group 1, group 2 demonstrated significantly improved clinical responses (group 1 vs. group 2, 84.8% vs. 100%, p = 0.0316). Although the safety profile was not significantly different between the two groups, the incidence of choleliths during ceftriaxone therapy in group 1 was higher than that in group 2 (31.3% vs. 9.1%, p = 0.174). Therefore, a 2 g once daily administration of ceftriaxone appeared to be a simple regimen adequate for the treatment of inpatients with mild-to-moderate aspiration pneumonia, which might not be heavily involved by anaerobes.
Pseudomonas fluorescens Complex and Its Intrinsic, Adaptive, and Acquired Antimicrobial Resistance Mechanisms in Pristine and Human-Impacted Sites
Authors: Silverio Myllena Pereira , Kraychete Gabriela Bergiante , Rosado Alexandre Soares , Bonelli Raquel Regina
Published: July 2022

Pseudomonas spp. are ubiquitous microorganisms that exhibit intrinsic and acquired resistance to many antimicrobial agents. Pseudomonas aeruginosa is the most studied species of this genus due to its clinical importance. In contrast, the Pseudomonas fluorescens complex consists of environmental and, in some cases, pathogenic opportunistic microorganisms. The records of antimicrobial-resistant P. fluorescens are quite scattered, which hinders the recognition of patterns. This review compiles published data on antimicrobial resistance in species belonging to the P. fluorescens complex, which were identified through phylogenomic analyses. Additionally, we explored the occurrence of clinically relevant antimicrobial resistance genes in the genomes of the respective species available in the NCBI database. Isolates were organized into two categories: strains isolated from pristine sites and strains isolated from human-impacted or metal-polluted sites. Our review revealed that many reported resistant phenotypes in this complex might be related to intrinsic features, whereas some of them might be ascribed to adaptive mechanisms such as colistin resistance. Moreover, a few studies reported antimicrobial resistance genes (ARGs), mainly β-lactamases. In-silico analysis corroborated the low occurrence of transferable resistance mechanisms in this Pseudomonas complex. Both phenotypic and genotypic assays are necessary to gain insights into the evolutionary aspects of antimicrobial resistance in the P. fluorescens complex and the possible role of these ubiquitous species as reservoirs of clinically important and transmissible ARGs.
Genomewide Analysis and Biological Characterization of Cathelicidins with Potent Antimicrobial Activity and Low Cytotoxicity from Three Bat Species
Authors: Choi Munjeong , Cho Hye-sun , Ahn Byeongyong , Prathap Somasundaram , Nagasundarapandian Soundrarajan , Park Chankyu
Published: July 2022

Cathelicidins are potent antimicrobial peptides with broad spectrum antimicrobial activity in many vertebrates and an important component of the innate immune system. However, our understanding of the genetic variations and biological characteristics of bat cathelicidins is limited. In this study, we performed genome-level analysis of the antimicrobial peptide cathelicidins from seven bat species in the six families, listed 19 cathelicidin-like sequences, and showed that the number of functional cathelicidin genes differed among bat species. Based on the identified biochemical characteristics of bat cathelicidins, three cathelicidins, HA-CATH (from Hipposideros armiger), ML-CATH (from Myotis lucifugus), and PD-CATH (from Phyllostomus discolor), with clear antimicrobial signatures were chemically synthesized and evaluated antimicrobial activity. HA-CATH showed narrow-spectrum antibacterial activity against a panel of 12 reference bacteria, comprising 6 Gram-negative and 6 Gram-positive strains. However, ML-CATH and PD-CATH showed potent antibacterial activity against a broad spectrum of Gram-negative and Gram-positive bacteria with minimum inhibitory concentration (MIC) of 1 and 3 μg/mL, respectively, against Staphylococcus aureus. ML-CATH and PD-CATH also showed antifungal activities against Candida albicans and Cryptococcus cuniculi with MIC of 5 to 40 μg/mL, respectively, and 80% inhibition of the metabolism of Mucor hiemalis hyphae at 80 μg/mL, while displaying minimal cytotoxicity to HaCaT cells. Taken together, although the spectrum and efficacy of bat cathelicidins were species-dependent, the antimicrobial activity of ML-CATH and PD-CATH was comparable to that of other highly active cathelicidins in vertebrates while having negligible cytotoxicity to mammalian cells. ML-CATH and PD-CATH can be exploited as promising candidates for the development of antimicrobial therapeutics.
The Effect of Herbal Supplements on Blood Pressure: Systematic Review and Meta-Analysis
Authors: Lipert Anna , Szadkowska Iwona , Matusiak-Wieczorek Ewelina , Kochan Ewa
Published: July 2022

Herbal supplements rich in phenolic compounds are evidenced to have a protective effect against cardiovascular diseases. Therefore, they are suggested to be included in diets for people with hypertension (HT). HT is a global health problem and is estimated to affect billions of people until the end of 2025. For this reason, every possible and effective solution preventing HT should be considered. The aim was to perform an updated meta-analysis and review of recently published studies to evaluate the effect of selected herbal supplements on blood pressure reduction. We searched the PubMed database with specified selection criteria, analysing the RCT studies from 2011 to 2021. A total of 31 studies were included in the analysis, and the meta-analysis was conducted on the data from 16 of them. The general effect size of all the supplements via placebo was d = 1.45, p < 0.05 for systolic blood pressure (SBP) and d = 0.31, p < 0.05 for diastolic blood pressure (DBP). The meta-analysis and review of the literature demonstrated that herbal supplements, such as resveratrol, cherry juice, beetroot juice, bergamot extracts, barberry, and pycnogenol, can be effective in blood pressure reduction and cardiovascular prevention, but attention should be paid to their appropriate dosage due to the possibility of side effects from the digestive system.
Design of Functional Powdered Beverages Containing Co-Microcapsules of Sacha Inchi P. huayllabambana Oil and Antioxidant Extracts of Camu Camu and Mango Skins
Authors: Chasquibol Nancy , Alarcón Rafael , Gonzales Billy Francisco , Sotelo Axel , Landoni Lourdes , Gallardo Gabriela , García Belén , Pérez-Camino M. Carmen
Published: July 2022

Sacha inchi Plukenetia huayllabambana oil (SIPHO) was co-microencapsulated, by spray drying using gum arabic as a coating material, with antioxidant extracts of camu camu (Myrciaria dubia (HBK) McVaugh) (CCSE) and mango (Mangifera indica) (MSE) skins obtained by ultrasound–microwave-assisted extraction (UMAE). The physicochemical characteristics of the microcapsules, such as, particle size, morphology, and moisture, as well as the encapsulation efficiency, the fatty acid composition, and oxidative stability, were determined in order to select the best formulation for the design of functional powdered beverages. The formulation with the highest amounts of ω3 acids and polyphenols was used to prepare a functional powdered beverage that contained ω3 (52.74%), antioxidant activity (324.80 mg AAE/100 g powder), and acceptable sensory attributes.
Experimental Conditions That Influence the Utility of 2′7′-Dichlorodihydrofluorescein Diacetate (DCFH2-DA) as a Fluorogenic Biosensor for Mitochondrial Redox Status
Authors: de Haan Lianne R. , Reiniers Megan J. , Reeskamp Laurens F. , Belkouz Ali , Ao Lei , Cheng Shuqun , Ding Baoyue , van Golen Rowan F. , Heger Michal
Published: July 2022

Oxidative stress has been causally linked to various diseases. Electron transport chain (ETC) inhibitors such as rotenone and antimycin A are frequently used in model systems to study oxidative stress. Oxidative stress that is provoked by ETC inhibitors can be visualized using the fluorogenic probe 2′,7′-dichlorodihydrofluorescein-diacetate (DCFH2-DA). Non-fluorescent DCFH2-DA crosses the plasma membrane, is deacetylated to 2′,7′-dichlorodihydrofluorescein (DCFH2) by esterases, and is oxidized to its fluorescent form 2′,7′-dichlorofluorescein (DCF) by intracellular ROS. DCF fluorescence can, therefore, be used as a semi-quantitative measure of general oxidative stress. However, the use of DCFH2-DA is complicated by various protocol-related factors that mediate DCFH2-to-DCF conversion independently of the degree of oxidative stress. This study therefore analyzed the influence of ancillary factors on DCF formation in the context of ETC inhibitors. It was found that ETC inhibitors trigger DCF formation in cell-free experiments when they are co-dissolved with DCFH2-DA. Moreover, the extent of DCF formation depended on the type of culture medium that was used, the pH of the assay system, the presence of fetal calf serum, and the final DCFH2-DA solvent concentration. Conclusively, experiments with DCFH2-DA should not discount the influence of protocol-related factors such as medium and mitochondrial inhibitors (and possibly other compounds) on the DCFH2-DA-DCF reaction and proper controls should always be built into the assay protocol.
Evaluation of Bioactive Compounds and Antioxidative Activity of Fermented Green Tea Produced via One- and Two-Step Fermentation
Authors: Xu Huiling , Hong Jong Hyoung , Kim Dabin , Jin Young Hun , Pawluk Alixander Mattay , Mah Jae-Hyung
Published: July 2022

This study investigated the influence of one- and two-step fermentation on bioactive compound production in fermented green tea, i.e., one-step fermented green tea (OFG) and two-step fermented green tea (TFG). One-step fermentation entailed acetic acid fermentation, while two-step fermentation consisted of lactic acid fermentation followed by acetic acid fermentation. Acetobacter pasteurianus PCH 325, isolated from an over-ripened peach, was selected for acetic acid fermentation based on its growth and organic acid production characteristics. Acetic acid fermentation conditions were optimized for one- and two-step fermentation: 3% fermentation alcohol for both processes; 8% and 4% sucrose, respectively; and fermentation at 25 °C for both processes. For lactic acid fermentation of TFG, the inoculum and optimized conditions reported previously were used. Under the optimized conditions, the acetic acid content in OFG and TFG increased 21.20- and 29.51-fold, respectively. Furthermore, through two-step fermentation, γ-aminobutyric acid and lactic acid were produced up to 31.49 ± 1.17 mg/L and 243.44 ± 58.15 mg/L, respectively, which together with acetic acid could contribute to the higher DPPH scavenging activity of TFG. This study suggests that two-step fermentation may be a valuable strategy in industry for raising the amount of acetic acid and/or providing additional bioactive compounds.
Mechanical Behaviors of Existing Large-Diameter Tunnel Induced by Horseshoe-Shaped Undercrossing Twin Tunnels in Gravel
Authors: Li Jianye , Fang Qian , Liu Xiang , Du Jianming , Wang Gan , Wang Jun
Published: July 2022

This article investigates and presents a case study on the Beijing Subway Line 12 excavation beneath the existing Qinghuayuan Tunnel. The composite pre-reinforcement technique was used in conjunction with the shallow tunneling method to control the distortion of the existing large-diameter tunnel. When building twin tunnels underneath, this strategy considerably decreased the impact on the existing large-diameter tunnel. To systematically study the mechanical response of the existing large-diameter tunnel, a variety of sensors was embedded in the prefabricated segments just above the new twin tunnels. During the undercrossing twin tunnels procedure, the earth pressure, tunnel crown settlement, opening width of the segment joint, and the circumferential strain of the large-diameter existing tunnel were all measured. The settlement development of the existing large-diameter tunnel was categorized under six stages: (1) sedimentation, (2) heave, (3) second sedimentation, (4) second heave, (5) third sedimentation, and (6) steady state. The joint opening of the existing large-diameter tunnel changed sharply during the new undercrossing twin tunnels. The earth pressure and concrete stress of the linings rapidly increased during the new undercrossing twin tunnels. The majority of the reinforcement and concrete stresses were compressive and far lower than the yield strength, indicating that the tunnel was in a safe working condition.
Special Issue on Materials and Technologies in Oral Research
Authors: Petrini Morena , Gennai Stefano
Published: July 2022

The introduction of novel materials and technologies in oral research has permitted the rapid evolution of dentistry, as confirmed by the increasing number of publications on this topic [...]
Evaluation of Biobed Bio-Mixture from Olive Oil Mill Wastewater Treatment as a Soil Organic Amendment in a Circular Economy Context
Authors: Kinigopoulou Vasiliki , Hatzigiannakis Evangelos , Guitonas Athanasios , Oikonomou Efstathios K. , Stefanou Stefanos , Gasparatos Dionisios
Published: July 2022

This study, based on circular economy principles and sustainable development practices, aims to present the results of soil samples analysis after their mixture with a biobed bio-mixture of straw, soil and compost, used for two consecutive years as organic bio-filter of olive oil mill wastewater. So far, exhausted bio-mixtures used in biobeds to minimize pesticide point-source contamination turned out to contain residues of pesticides, and they are considered hazardous wastes; thus, they require special treatment before their disposal. Contrariwise, saturated bio-mixtures from bio-bed systems utilized for olive mill wastewater (OMWW) treatment not only do not require any special treatment before their final disposal but also can be exploited as a soil amendment. To this end, the effects of the used bio-mixture application in three different proportions as a soil amendment on the physical and chemical properties of medium-texture soil were investigated. The application of water simulating a typical irrigation period during a growing season took place. Upon completion of the water application, soil samples were collected from two different depths of the columns and analyzed, and leachates collected from the columns were also analyzed. Soil texture, organic matter, calcium carbonate, electrical conductivity (EC), pH, total nitrogen, nitrates, nitrites, ammonium, available phosphorus, exchangeable potassium, sodium, calcium and magnesium, exchangeable sodium percentage (ESP), cation exchange capacity (CEC), available iron, manganese, copper, zinc and boron were monitored in the soil samples as indexes of potential soil amendment, and EC, pH, nitrates, potassium, sodium, calcium, magnesium, sodium adsorption ratio (SAR), total hardness, iron, manganese, copper, zinc and boron were monitored in the leachates as indexes of potential groundwater contamination.The study demonstrated the effective use of saturated bio-mixture as an organic soil amendment, while the impact of selected amendments on groundwater was the minimum.
Crushing Analysis and Optimization of Adjacent Variable Thickness Hexagonal Tubes
Authors: Xu Kai , Xu Ping , Xing Jie , Yao Shuguang , Huang Qi
Published: July 2022

In this study, we proposed a new adjacent variable thickness hexagonal tube (AVTHT) and performed crushing analysis and crashworthiness optimization under multiple loadings. First, the finite element models were constructed and validated by experiments with four configurations of AVTHTs. Then, the numerical simulations under axial loading and multiple oblique loadings indicated that AVTHTs under various loading angles (0°, 10°, 20°, and 30°) and three patterns (α, β, and θ) exhibited different deformation modes, force-displacement characteristics, and crashworthiness indices. This suggested that we could change and determine the plate thickness configuration to make the AVTHTs exhibit the expected crushing performance under multiple loadings. Therefore, multi-objective optimization for minimizing maximum crushing force with multiple loadings (Fmaxw) and maximizing specific energy absorption with multiple loadings (SEAw) by changing the thickness configuration under multiple loadings was conducted. The results determined the thickness design domains and indicated that certain thickness ranges should be avoided, such as the ranges of 1.55≤t1≤1.6 and 1.85≤t1≤1.95, which was helpful for getting AVTHTs to achieve excellent crushing performance in railway vehicles. In the pareto results, increasing t1 would not always increase the Fmaxw and SEAw. For example, when 1.75≤t1≤1.8, increasing t1 would lead to decline of Fmaxw and SEAw.
Fast Variable-Temperature Cryogenic Blackbody Sources for Calibration of THz Superconducting Receivers
Authors: Tarasov Mikhail , Gunbina Aleksandra , Chekushkin Artem , Strelkov Mikhail , Edelman Valerian
Published: July 2022

An electrically heated blackbody radiation source comprising thin metal film on a dielectric substrate and an integrating cavity was designed, fabricated, and experimentally studied at frequencies from 75 to 500 GHz. Analytical and numerical modeling were performed to optimize the emissivity, spectral uniformity, and modulation frequency of the radiation source with the spherical integrating cavity and thin film absorber. The blackbody emissivity (absorptivity) increased from 0.3 to 0.5 for the bare thin film on dielectric substrate, and up to 0.95 when it was placed inside the integrating cavity. The fabricated source mounted at the 0.5 K stage was used to measure the response time of a few microseconds and for sensitivity measurement down to 10−18 W/Hz1/2 of the superconductor–insulator–normal metal–insulator–superconductor (SINIS) detector at 100 mK.
Parallel Accelerated Fifth-Order WENO Scheme-Based Pipeline Transient Flow Solution Model
Authors: Mo Tiexiang , Li Guodong
Published: July 2022

The water hammer phenomenon is the main problem in long-distance pipeline networks. The MOC (Method of characteristics) and finite difference methods lead to severe constraints on the mesh and Courant number, while the finite volume method of the second-order Godunov scheme has limited intermittent capture capability. These methods will produce severe numerical dissipation, affecting the computational efficiency at low Courant numbers. Based on the lax-Friedrichs flux splitting method, combined with the upstream and downstream virtual grid boundary conditions, this paper uses the high-precision fifth-order WENO scheme to reconstruct the interface flux and establishes a finite volume numerical model for solving the transient flow in the pipeline. The model adopts the GPU parallel acceleration technology to improve the program’s computational efficiency. The results show that the model maintains the excellent performance of intermittent excitation capture without spurious oscillations even at a low Courant number. Simultaneously, the model has a high degree of flexibility in meshing due to the high insensitivity to the Courant number. The number of grids in the model can be significantly reduced and higher computational efficiency can be obtained compared with MOC and the second-order Godunov scheme. Furthermore, this paper analyzes the acceleration effect in different grids. Accordingly, the acceleration effect of the GPU technique increases significantly with the increase in the number of computational grids. This model can support efficient and accurate fast simulation and prediction of non-constant transient processes in long-distance water pipeline systems.
There Is Not Only Cupressus sempervirens L.: A Review on the Phytochemistry and Bioactivities of the Other Cupressus L. Species
Authors: Frezza Claudio , De Vita Daniela , Sciubba Fabio , Toniolo Chiara , Tomassini Lamberto , Nicoletti Marcello , Franceschin Marco , Guiso Marcella , Bianco Armandodoriano , Serafini Mauro , Foddai Sebastiano
Published: July 2022

This review article reports for the first time phytochemistry, ethnobotanical uses and pharmacological activities of all Cupressus L. species other than Cupressus sempervirens L. Indeed, the literature survey showed how many other Cupressus species are rich of important phytochemical compounds, widely used in the ethnobotanical field for several purposes and endowed with interesting biological activities, even if they are somehow neglected by the scientific community. This review aims to continue the study of these other Cupressus species and promote more research on them.
Hidden Dangerous Object Recognition in Terahertz Images Using Deep Learning Methods
Authors: Danso Samuel Akwasi , Shang Liping , Hu Deng , Odoom Justice , Liu Quancheng , Nana Esi Nyarko Benedicta
Published: July 2022

As a harmless detection method, terahertz has become a new trend in security detection. However, there are inherent problems such as the low quality of the images collected by terahertz equipment and the insufficient detection accuracy of dangerous goods. This work advances BiFPN at the neck of YOLOv5 of the deep learning model as a mechanism to improve low resolution. We also perform transfer learning, thereby fine-tuning the pre-training weight of the backbone for migration learning in our model. Results from experimental analysis reveal that mAP@0.5 and mAP@0.5:0.95 values witness a percentage increase of 0.2% and 1.7%, respectively, attesting to the superiority of the proposed model to YOLOv5, which is the state-of-the-art model in object detection.
Provenance and Tectonic Setting of Formation of Quaternary Sedimentary Successions from the Songhua River, Northeast China
Authors: Kan Wenguang , Yang Zailin , Yu Liangliang , Sun Menghan
Published: July 2022

Drilling has been conducted to investigate the petrogeochemistry of the Late Pleistocene Guxiangtun Formation and Holocene Wenquanhe Formation in Northeast China. Both Guxiangtun and Wenquanhe Formations are fluvial facies, which are composed mainly of quartz and feldspar, with minor mica and clay minerals. To understand the provenance and tectonic setting of these sediments, geochemical analyses of fifteen selected samples from the drill core have been carried out. Compared to the composition of the upper continental crust (UCC), the sediments exhibit higher SiO2, similar TiO2 and K2O, and lower Fe2O3, MgO, MnO, CaO, and Na2O contents. The bivariant plot of Th/Sc versus Zr/Sc ratios indicates the contribution from recycled sedimentary provenance for our studied sediments; furthermore, the low to medium degree of weathering of these sediments is commonly indicated by the chemical index of alteration (CIA) of 52. The discriminant function diagram using major elements shows a mixed provenance of the sediments, including quartzose sedimentary and felsic igneous rocks. According to the Fe2O3+MgO vs. K2O/Na2O plot and Th–Sc–Zr/10 diagram, the sediments under the investigation fall mostly within the active continent margin field.
Image Interpolation with Regional Gradient Estimation
Authors: Jia Zuhang , Huang Qingjiu
Published: July 2022

This paper proposes an image interpolation method with regional gradient estimation (GEI) to solve the problem of the nonlinear interpolation method not sufficiently considering non-edge pixels. First, the approach presented in this paper expanded on the edge diffusion idea used in CGI and proposed a regional gradient estimation strategy to improve the problem of gradient calculation in the CGI method. Next, the gradient value was used to determine whether a pixel was an edge pixel. Then, a 1D directional filter was employed to process edge pixels while interpolating non-edge pixels using a 2D directionless filter. Finally, we experimented with various representative interpolation methods for grayscale and color images, including the one presented in this paper, and compared them in terms of subjective results, objective criteria, and computational complexity. The experimental results showed that GEI performed better than the other methods in an experiment concerning the visual effect, objective criteria, and computational complexity.
Salt-Fog Corrosion Behavior of GCr15 Steels Treated by Ultrasonic Strengthening Grinding Process
Authors: Xie Xincheng , Guo Zhongning , Zhao Zhuan , Liang Zhongwei , Wu Jun , Liu Xiaochu , Xiao Jinrui
Published: July 2022

In this paper, the corrosion resistance of four GCr15 steel samples has been investigated. Three samples were initially surface-treated by ultrasonic shot peening (USP), a dry ultrasonic strengthening grinding process (DUSGP), and a wet ultrasonic strengthening grinding process (WUSGP), respectively, while another one was only polished. Then, all the processed samples were subjected to salt spray corrosion. Sample properties, such as capacitance arc, self-corrosion potential (Ecorr), self-corrosion current density (Icorr), corrosion morphology, and corrosion products were analyzed. Results show that the sample treated by WUSGP has the best corrosion resistance, which can be attributed to the high dislocation density, small grain size, needle-like and lath-like shape of martensite content formed in the treatment, which hinders Cl− from eroding the matrix. The obtained corrosion pits and cracks in Sample WUSGP show a width of approximately 1.4 µm and 2.1 µm, respectively, degrading 78% and 75% compared to polishing. The possible corrosion mechanism of the samples has been discussed. The findings denote that the treatment fused ceramic balls, strengthened liquid, and corundum in USP could be an efficient method to improve the corrosion resistance of some mechanical parts.
Generalized Sketches for Streaming Sets
Authors: Guo Wenhua , Ye Kaixuan , Qi Yiyan , Jia Peng , Wang Pinghui
Published: July 2022

Many real-world datasets are given as a stream of user–interest pairs, where a user–interest pair represents a link from a user (e.g., a network host) to an interest (e.g., a website), and may appear more than once in the stream. Monitoring and mining statistics, including cardinality, intersection cardinality, and Jaccard similarity of users’ interest sets on high-speed streams, are widely employed by applications such as network anomaly detection. Although estimating set cardinality, set intersection cardinality, and set Jaccard similarity, respectively, is well studied, there is no effective method that provides a one-shot solution for estimating all these three statistics. To solve the above challenge, we develop a novel framework, SimCar. SimCar online builds an order-hashing (OH) sketch for each user occurring in the data stream of interest. At any time of interest, one can query the cardinalities, intersection cardinalities, and Jaccard similarities of users’ interest sets. Specially, using OH sketches, we develop maximum likelihood estimation (MLE) methods to estimate cardinalities and intersection cardinalities of users’ interest sets. In addition, we use OH sketches to estimate Jaccard similarities of users’ interest sets and build locality-sensitive hashing tables to search for users with similar interests with sub-linear time. We evaluate the performance of our methods on real-world datasets. The experimental results demonstrate the superiority of our methods.
Pavement Surface Defect Detection Using Mask Region-Based Convolutional Neural Networks and Transfer Learning
Authors: He Yang , Jin Zihan , Zhang Jiqiao , Teng Shuai , Chen Gongfa , Sun Xiaoli , Cui Fangsen
Published: July 2022

Pavement defect detection is critical for pavement maintenance and management. Meanwhile, the accurate and timely detection of pavement defects in complex backgrounds is a huge challenge for maintenance work. Therefore, this paper used a mask region-based convolutional neural network (Mask R-CNN) and transfer learning to detect pavement defects in complex backgrounds. Twelve hundred pavement images were collected, and a dataset containing corresponding instance labels of the defects was established. Based on this dataset, the performance of the Mask R-CNN was compared with faster region-based convolutional neural networks (Faster R-CNNs) under the transfer of six well-known backbone networks. The results confirmed that the classification accuracy of the two algorithms (Mask R-CNN and Faster R-CNN) was consistent and reached 100%; however, the average precision (AP) of the Mask R-CNN was higher than that of Faster R-CNNs. Meanwhile, the testing time of the models using a feature pyramid network (FPN) was lower than that of other models, which reached 0.21 s per frame (SPF). On this basis, the segmentation performance of the Mask R-CNN was further analyzed at three learning rates (LRs). The Mask R-CNN performed best with ResNet101 plus FPN as its backbone structure, and its AP reached 92.1%. The error rate of defect quantification was between 4% and 16%. It has an ideal detection effect on multi-object and multi-class defects on pavement surfaces, and the quantitative results of the defects can provide a reference for pavement maintenance personnel.
Performance Deterioration of Underground Culverts Considering the Effect of Dissolution and Its Impact on the Surrounding Soil
Authors: Zhang Guochen , Xu Liqun , Chen Guanyun , Zhang Wenbing , Shen Zhenzhong , Ju Luyi , Li Xiaocui
Published: July 2022

To address the problem of dissolution damage during the long-term service of concrete hydraulic buildings, the concrete dissolution damage degree D and contact dissolution loss model with time were proposed by combining the results of indoor concrete dissolution tests. A mathematical model of the evolution of concrete parameters with time was developed. In the context of an underground concrete culvert project, a numerical analysis model of concrete dissolution deterioration was established, according to which the effects of different damage locations on the stress and displacement of concrete culverts were analyzed. The results show that the settlement value of the surface and the soil pore pressure value increase more when the bottom of the culvert is damaged by dissolution, and the settlement of the surface from the bottom damage is about 1.07~1.16 times of that from the top damage. When the damage position deviates from the center line of the culvert, the maximum point of vertical displacement in the transverse settlement trough of the ground surface deviates from the centerline of the culvert by about 3~5 m in the horizontal direction. At the bottom of the culvert, the concrete permeability coefficient reaches 6.957 × 10−8 m/s~8.354 × 10−8 m/s in about 13~16 years after the occurrence of dissolution damage, and local leakage occurs, causing a significant increase in the pore pressure of the soil near the leakage location. The overall settlement and uneven settlement resulting from the dual action of dissolution deterioration of concrete and infiltration pressure can have a serious impact on the upper channel buildings.
Comparative Study on the Synthesis of Path-Generating Four-Bar Linkages Using Metaheuristic Optimization Algorithms
Authors: Kang Yaw-Hong , Lin Jau-Wen , You Wei-Chen
Published: July 2022

Four-bar linkages are one of the most widely used mechanisms in industries. This paper presents a comparative study on the accuracy and efficiency of the optimum synthesis of path-generating four-bar linkages using five metaheuristic optimization algorithms. The utilized metaheuristic methods included two swarm intelligence-based algorithms, i.e., particle swarm optimization and hybrid particle swarm optimization, and three evolutionary-based algorithms, i.e., differential evolution, ensemble of parameters and mutation strategies in differential evolution, and linearly ensemble of parameters and mutation strategies in differential evolution. The objective function to be minimized is the sum of squares of the distance between the generated points and the precision points of a coupler point. The optimal design of four-bar linkages must meet the Grashof’s criteria and exhibit sequential constraints that can prevent the occurrence of order defect. This study investigated five representative cases of the dimensional synthesis of four-bar path generators with and without prescribed timing and compared the optimal solutions of the utilized five metaheuristic methods to those of previously reported algorithms in literature. The improved metaheuristic methods exhibited superior optimal solution and enhanced reliability compared to the original methods. Moreover, three improved metaheuristic methods were not only easy implemented, but also more efficient for solving the optimal synthesis problems, particularly for high dimensional problems.
Morphology of Dome- and Tepee-Like Landforms Generated by Expansive Hydration of Weathering Anhydrite: A Case Study at Dingwall, Nova Scotia, Canada
Authors: Jarzyna Adrian , Bąbel Maciej , Ługowski Damian , Vladi Firouz
Published: July 2022

The gypsum-anhydrite rocks in the abandoned quarry at Dingwall (Nova Scotia, Canada) are subjected to physical and chemical weathering, including hydration of the anhydrite, i.e., its transformation into secondary gypsum under the influence of water. This process is known to lead to the localized volume increase of the rock and the formation of spectacular hydration landforms: domes, tepees and ridges. Cavities appearing in the interior of these domes are often unique hydration caves (Quellungshöhlen in German). For the first time, this paper gives detailed geomorphometric characteristics of the 77 dome- and tepee-like hydration landforms growing today at Dingwall based on their digital surface models and orthophotomaps, made with the method of photogrammetry integrated with direct measurements. The length of hydration landforms varies from 1.86 to 23.05 m and the relative height varies from 0.33 to 2.09 m. Their approximate shape in a plan view varies from nearly circular, through oval, to elongated with a length-to-width ratio rarely exceeding 5:2. Length, width and relative height are characterized by moderate mutual correlation with proportional relations expressed by linear equations, testifying that the hydration landforms generally preserve the same or very similar shape independent of their sizes. The averaged thickness of the detached rock layer ranges from 6 to 46 cm. The size of the forms seems to depend on this thickness—the forms larger in extent (longer) generally have a thicker detached rock layer. Master (and other) joints and, to a lesser extent, layering in the bedrock influence the development of hydration landforms, particularly by controlling the place where the entrances are open to internal cavities or caves. Three structural types of the bedrock influencing the growth of hydration forms were recognized: with master joints, with layering and with both of them. The latter type of bedrock has the most complex impact on the morphology of hydration landforms because it depends on the number of master joint sets and the mutual orientation of joints and layering, which are changeable across the quarry. The durability of the hydration forms over time depends, among others, on the density of fractures in the detached rock layer.