bluuebunny/crossref_metadata_2025 huggingface dataset:
Observer-Based Backstepping Adaptive Force Control of Electro-Mechanical Actuator with Improved LuGre Friction Model
Authors: Zhang Wensen , Ping Zilong , Fu Yongling , Zheng Shicheng , Zhang Peng
Published: August 2022

A dynamic load simulator, which can reproduce on-ground aerodynamic hinge moment of control surface, is an essential rig for the performance and stability test of an aircraft actuation system. In this paper, an observer-based backstepping adaptive control (OBAC) strategy with an improved friction model is proposed to deal with the force tracking problem of an electro-mechanical actuator under the influence of nonlinear friction and lumped disturbances. First, The LuGre friction model is improved by introducing the load effect of electrical linear load simulator (ELLS), and both dynamic and static parameters are identified with experimental data. Then, the ELLS system is divided into a loading subsystem and actuation subsystem for backstepping controller deign. The estimation of the position disturbance is obtained using an extended state observer and used for feedforward compensation for the loading subsystem. To reject the disturbance of friction parameter uncertainties for actuation subsystem, a friction scale factor with a reasonable adaptive updating law is introduced during the friction compensation process. Finally, the stability of the whole closed-loop system is demonstrated using a Lyapunov-based method, and experiments are performed to validate the effectiveness of the developed algorithm.
Nectar Abundance and Nectar Composition in Selected Rubus idaeus L. Varieties
Authors: Kostryco Mikołaj , Chwil Mirosława
Published: August 2022

The increasing commercial production of R. idaeus offers insects nectar and pollen rewards, thus increasing the chance of cross-pollination, which enhances fruit yields. The knowledge of nectar characteristics may help farmers/beekeepers to improve the quality of their products. Therefore, we determined and compared nectar weight, sugar concentration and weight, and the qualitative and quantitative composition of sugars and amino acids in the nectar of six raspberry cultivars: three biennial and three repeated fruiting cultivars. The nectary abundance in these cultivars ranged between 20.2 ± 3.84 mg (‘Polka’) and 26.4 ± 7.3 mg (‘Glen Ample’) of nectar per flower with a sugar concentration of 34.6 ± 5.61–47.3 ± 9.33%. The contents of glucose and fructose (g/100 g) were in the range from 42.96 ± 0.71 (‘Glen Ample’) to 46.94 ± 0.55 (‘Laszka’) and from 50.7 ± 1.43 (‘Polka’) to 54.2 ± 0.72 (‘Radziejowa’). Sucrose was detected only in ‘Glen Ample’ (5.6 ± 1.12 g/100 g) and ‘Polka’ (6.2 ± 0.95 g/100 g). Taking into account the increasing sugar weight in the nectar, the cultivars were ranked as follows: ‘Polka’ < ‘Polana’ < ‘Radziejowa’ < ‘Pokusa’ < ‘Laszka’ < ‘Glen Ample’. The nectar of the analyzed raspberry cultivars was classified as a hexose-dominant type. Aspartic acid, glutamic acid, and proline were the most dominant endogenous amino acids, whereas exogenous acids were dominated by lysine and leucine. The present results provide valuable information about the nutritious value of R. idaeus nectar for pollinators.
Biochar Enhances Plant Growth, Fruit Yield, and Antioxidant Content of Cherry Tomato (Solanum lycopersicum L.) in a Soilless Substrate
Authors: Simiele Melissa , Argentino Oriana , Baronti Silvia , Scippa Gabriella Stefania , Chiatante Donato , Terzaghi Mattia , Montagnoli Antonio
Published: August 2022

Biochar soil amendment can improve growing medium water and nutrient status and crop productivity. A pot experiment was conducted using Solanum lycopersicum var. cerasiforme plants to investigate the effects of biochar amendment (20% application rate) on a soilless substrate, as well as on plant growth, fruit yield, and quality. During the experiment, substrate characteristics, plant morphological traits, and root and leaf C/N content were analyzed at three sampling points defined as early stage (36 days after germination), vegetative stage (84 days a. g.), and fruit stage (140 days a. g.). Fruit morphological traits, titratable acidity, lycopene, and solid soluble content were measured at the end of the experiment. Biochar ameliorated substrate characteristics (Nav increase of 17% and Ctot increase of 13% at the beginning of the study), resulting in a promotion effect on plant root, shoot, and leaf morphology mainly at the vegetative and fruit stages. Indeed, at these two sampling points, the biochar-treated plants had a greater number of leaves (38 and 68 at the vegetative and fruit stages, respectively) than the untreated plants (32 and 49, respectively). The biochar also increased leaf area with a rise of 26% and 36% compared with the values measured in the untreated plants. Moreover, the amendment increased twofold root length, root surface area, and root, stem, and leaf biomasses in comparison with untreated plants. Regarding plant productivity, although fruit morphology remained unchanged, biochar increased flower and fruit numbers (six times and two times, respectively), acidity (75%), lycopene (28%), and solid soluble content (16%). By unveiling promoting changes in morphological traits, fruit number, and antioxidant content occurring in cherry tomato plants growing in a biochar-treated soilless substrate, it could be possible to highlight the importance of biochar for future applications in the field for enhancing plant production and fruit quality in a sustainable agriculture framework.
Artificial Lighting Photoperiod Manipulation Approach to Improve Productivity and Energy Use Efficacies of Plant Factory Cultivated Stevia rebaudiana
Authors: Rengasamy Narendren , Othman Rofina Yasmin , Che Hang Seng , Harikrishna Jennifer Ann
Published: August 2022

Stevia rebaudiana cultivated in non-native tropical conditions tends to flower early, halting vegetative growth, resulting in lower biomass and yields of its valued steviol glycoside metabolites. While indoor cultivation allows manipulation of artificial lighting to mimic optimal conditions, it introduces an additional energy cost. The study objectives were to assess photoperiod manipulation as a lighting strategy to increase overall biomass and metabolite yields as well as to improve the efficacy of the electrical energy used for indoor cultivation of Stevia rebaudiana in non-native environmental conditions. Stevia was grown under artificial lighting with red, green, and blue wavelengths with photoperiods of 8 h, 12 h, 16 h, and intermittent light amounting to 16/24 h, each with a constant Daily Light Integral (DLI) of 7.2 mol m−2 day−1. Yield was measured as leaf dry weight biomass in combination with Liquid chromatography–mass spectrometry (LCMS) analysis of Stevioside and Rebaudioside A content. The photon flux density of the artificial and natural light as measured by a spectroradiometer, and the energy use data collected with a three-phase power quality logger, were compared for each treatment tested and to that from plants grown under natural light irradiation in a greenhouse. Yield and energy data were used to determine the efficacies of the lighting systems tested. Stevia plants under a continuous 16-h photoperiod (16H) had the highest productivity, resulting in the highest biomass accumulation and metabolite concentrations. The Stevioside and Rebaudioside A yields per plant were 975% higher than those obtained under natural daylight and day-neutral tropical photoperiod. Overall energy use and photon conversion efficacies were also highest under 16H at 65.10 g kWh−1 for biomass accumulation, 12.40 g kWh−1 for metabolite yields and 7.5 mg mol−1 for photon conversion. These findings support the application of photoperiod manipulation as a viable approach to increase productivity and improve energy use efficacies for indoor cultivation of Stevia rebaudiana plants under artificial lighting in non-native environments with the 16-h photoperiod under red and blue artificial light supplemented with green spectrum as the best option.
Transfer of Durable Stripe Rust Resistance Gene Yr39 into Four Chinese Elite Wheat Cultivars Using Marker-Assisted Selection
Authors: Zheng Xiaochen , Zhou Jianian , Zhang Min , Tan Wenjing , Ma Chunhua , Tian Ran , Yan Qiong , Li Xin , Xia Chongjing , Kang Zhensheng , Chen Xianming , Zhou Xinli , Yang Suizhuang
Published: August 2022

Wheat gene Yr39 confers durable high-temperature adult-plant (HTAP) resistance to stripe rust caused by Puccinia striiformis f. sp. tritici, one of the most destructive diseases of wheat worldwide. The objective of this study was to transfer Yr39 into four Chinese elite wheat cultivars. Backcross inbred line populations were developed from four Chinese wheat cultivars Chuanmai 42 (CM42), Bainong Aikang 58 (AK58), Han 6172 (H6172) and Zhengmai 9023 (ZM9023) crossed with a Yr39 single-gene line. The F1, BC1F1 and BC1F6 lines were genotyped using resistance gene analogs polymorphism (RGAP) markers Xwgp36, Xwgp44 and Xwgp43, which are closely linked to Yr39. Progeny lines selected with the markers for Yr39 were evaluated in the field for stripe rust resistance and agronomic traits including plant height, tiller numbers, spike grain numbers and thousand-grain weight. Eleven lines were selected with stripe rust resistance and desirable agronomic traits. These lines with production potential can be used for further testing in various wheat production regions and as germplasm resources for breeding new wheat cultivars with durable stripe rust resistance, high yield, and adaptation to different production environments.
One-Time Nitrogen Fertilizer Application Using Controlled-Release Urea Ensured the Yield, Nitrogen Use Efficiencies, and Profits of Winter Wheat
Authors: Cui Peiyuan , Chen Zhixuan , Ning Qianqian , Wei Haiyan , Zhang Haipeng , Lu Hao , Gao Hui , Zhang Hongcheng
Published: August 2022

One-time fertilization with controlled-released fertilizer (CRF) is a promising way for reducing labor cost, increasing nitrogen use efficiency (NUE) and alleviating environmental pollution in winter wheat (Triticum aestivum L.) cultivation. However, CRF release characteristics are related to various factors such as soil properties, temperature and precipitation, and further study is needed in developing suitable fertilizer formulas adapting to local conditions. In this study, five types of CRF were used for a one-time application in a two-year field experiment conducted at two sites with two wheat cultivars. Their effects on soil inorganic nitrogen (SIN) content, nitrogen uptake, wheat growth and grain yield were investigated. The results indicated that nitrogen supply in the CRF-60/80 treatments not only ensured the tiller differentiation at the early growth stage, but also provided adequate SIN after the jointing stage, thereby facilitating the dry matter accumulation and improving post-anthesis photosynthates accumulating in grains. When compared with conventional split fertilization, the CRF-60 and 80 treatments improved the NUE by 9.7–12.1%, and boosted farmers’ economic efficiency by 282.4–327.2 CNY ha−1. According to our research, a one-time application of CRF-60 and CRF-80 could meet the needs of the two-peak nitrogen demand of wheat in Jiangyan and Yanghzou respectively, therefore increasing NUE and having low labor costs for wheat fertilizer application.
Soil Biological Activity, Carbon and Nitrogen Dynamics in Modified Coffee Agroforestry Systems in Mexico
Authors: Ayala-Montejo Diana , Valdés-Velarde Eduardo , Benedicto-Valdés Gerardo Sergio , Escamilla-Prado Esteban , Sánchez-Hernández Rufo , Gallardo Juan Fernando , Martínez-Zurimendi Pablo
Published: August 2022

(1) Background: Coffee agroforestry systems (CAFS) in Veracruz, Mexico, are being displaced by avocado monocultures due to their high economic value. This change can generate alterations in the type of organic residues produced and soil biological activity (SBA) which is sensitive to climatic variations, changes in floristic composition, and agronomic management. It can be evaluated through soil respiration and macrofauna, both related to soil carbon (C) and nitrogen (N) dynamics. The objective was to: (1) Analyze the variation of SBA as well as the C and N dynamics in modified coffee agroforestry systems; (2) Methods: Three CAFS (renewed, intensive pruning, and with the introduction of avocados) and an avocado plantation were compared. The evaluations were conducted during the period 2017–2019. Soil parameters (respiration, macrofauna, C and N contents) and C content of plant biomass were measured in plots of 25 × 25 m2 from three soil depths in triplicate. Spearman’s test and a principal component analysis were performed to determine the structural dependence on C and N dynamics; (3) Results: The introduction of avocado showed the lowest soil respiration values (with 193 g CO2 ha−1 h−1 at 0–10 cm depth), this system did not display soil macrofauna and increased soil organic carbon content. The soil C/N ratio was sensitive to the introduction of avocado. Correlation between soil respiration and litter-related parameters was positive, but it was negatively correlated with soil organic matter and total soil nitrogen, explaining 67.7% of the variation; (4) Conclusions: Modification of CAFS generated variations in the SBA and soil C and N contents.
Influence of Kosakonia sp. on the Growth of Arachis hypogaea L. on Arid Soil
Authors: Narayanan Mathiyazhagan , Pugazhendhi Arivalagan , David Selvaraj , Chi Nguyen Thuy Lan , Nasif Omaima , Alharbi Sulaiman Ali , Ma Ying
Published: August 2022

The current study focused on enumerating the potential plant growth-promoting rhizobacteria (PGPR) from the rhizosphere of Arachis hypogaea L. Among the several colonies grown on an Ashby plate, only seven isolates (Ah1 to Ah7) had nitrogen-fixing potential. The Ah4 isolate showed higher potential for plant growth-promoting (PGP) activities than the other isolates. This isolate was recognized as Kosakonia sp. MGR1 through 16S rRNA sequencing with 99.7% similarity to nitrogen-fixing Kosakonia genus and 61% match with K. cowanii in phylogenetic tree analysis. Kosakonia sp. MGR1 had the potential to produce an excellent quantity (26.17 µg·mL−1) of indole-3-acetic acid (IAA) in 6% tryptophan-enriched media than the other concentrations (2%, 4%, 8%, and 10%). Additionally, it contained remarkable phosphate-solubilizing efficiency of tricalcium phosphate (29.3 µg·mL−1) in 5 days of incubation. The growth conditions of Kosakonia sp. were optimized as 35 °C, pH 7.5, and 48 h of incubation with glucose. The isolate MGR1 produced 96.35 ± 3.45, 89.6 ± 5.61, and 99.21 ± 5.24 µg·mL−1 of IAA, nitrogen, and soluble phosphate, respectively. Furthermore, Kosakonia sp. MGR1 had the potential to enhance the growth and biomolecule contents of A. hypogaea L. The results concluded that Kosakonia had admirable PGP activities; hence, it showed a significant impact on the active growth and biomolecules of A. hypogaea L.
Remote Sensing Prescription for Rice Nitrogen Fertilizer Recommendation Based on Improved NFOA Model
Authors: Yang Min , Xu Xingang , Li Zhongyuan , Meng Yang , Yang Xaiodong , Song Xiaoyu , Yang Guijun , Xu Sizhe , Zhu Qilei , Xue Hanyu
Published: August 2022

Precise fertilization of rice depends on the timely and effective acquisition of fertilizer application recommended by prescription maps in large-scale cropland, which can provide fertilization spatial information reference. In this paper, the prescription map was discussed based on the improved nitrogen fertilizer optimization algorithm (NFOA), using satellite and unmanned aerial vehicle (UAV) imagery, and supplemented by meteorological data. Based on the principles of NFOA, firstly, remote sensing data and meteorological data were collected from 2019 to 2021 to construct a prediction model for the potential yield of rice based on the in-season estimated yield index (INSEY). Secondly, based on remote sensing vegetation indices (VIs) and spectral features of bands, the grain nitrogen content (GNC) prediction model constructed using the Random Forest (RF) algorithm was used to improve the values of GNC taken in the NFOA. The nitrogen demand for rice was calculated according to the improved NFOA. Finally, the nitrogen fertilizer application recommended prescription map of rice in large-scale cropland was generated based on UAV multispectral images, and the economic cost-effectiveness of the prescription map was analyzed. The analysis results showed that the potential yield prediction model of rice based on the improved INSEY had a high fitting accuracy (R2 = 0.62). The accuracy of GNC estimated with the RF algorithm reached 96.3% (RMSE = 0.07). The study shows that, compared with the non-directional and non-quantitative conventional tracking of N fertilizer, the recommended prescription map based on the improved NFOA algorithm in large-scale cropland can provide accurate information for crop N fertilizer variable tracking and provide effective positive references for the economic benefits of rice and ecological benefits of the field environment.
Canopy Temperature and Heat Flux Prediction by Leaf Area Index of Bell Pepper in a Greenhouse Environment: Experimental Verification and Application
Authors: Jeon Youngkwang , Cho Lahoon , Park Sunyong , Kim Seokjun , Lee Chunggeon , Kim Daehyun
Published: August 2022

Accurate classification of multilayered plants is vital to understanding the interaction of each canopy in a greenhouse environment and designing plant models based on the irradiation, canopy temperature, transpiration, and heat flux by the leaf area index (LAI). Based on the measurements from a greenhouse in operation, plant models for each LAI are discussed in this study. If the heat flux between plants and air can be accurately predicted through plant models using LAI, the heating and cooling load in various virtual greenhouses with densely planted crops can be predicted. To enhance the measurement accuracy, a temperature and humidity sensor with an aspirated shield, an infrared canopy sensor, and CO2 sensor were installed. The plant environment was measured with a portable pyranometer, porometer, ceptometer, and anemometer. The measurements were inputted to the plant models, and the canopy temperature was calculated. The canopy temperature from the models was evaluated for reliability by comparing it with field measurements (R2 = 0.98 and RMSE = 0.46). The results indicated that the big leaf model is suitable when the air circulation layer is larger than the canopy size, but when physical properties of the plant change band affect the LAI, as in a greenhouse, a multi-layer model should be considered.
Phenotypic Diversity and Characterization of the Southern African Bambara Groundnut Germplasm Collection for Grain Yield and Yield Components
Authors: Siwale Julius , Labuschagne Maryke , Gerrano Abe Shegro , Mbuma Ntombokulunga W.
Published: August 2022

Bambara groundnut is a highly nutritious underutilized legume crop, which can be cultivated in unfavorable environments, has the potential to address food security and can significantly contribute to climate-smart agriculture. The objectives of this study were to determine the phenotypic diversity and characterize a southern African bambara groundnut germplasm collection for grain yield and yield components, to identify superior bambara accessions and to determine the correlation between measured traits. The 100 bambara accessions were planted in two different locations over two seasons. There was significant variability among the accessions, locations, seasons and their interactions for all traits. Low broad-sense heritability values (<0.5) were observed for almost all traits. Significant positive correlations between all measured traits were observed. High-yielding accessions; WS 42 (AS), MV 67-1, K 5, AS 9, SCORE 1 and SB 12-3 were identified. Bambara accessions 224 (RF-7684), 179 (AB 16-5C), 121 (Red Ex Zimbabwe), 62 (SB 8-3), 9 (SB 4-1), 181 (SB 8-1B), 89 (AS 20), 217 (RF-6221), 94 (K 5), 177 (S1 Sel2) and 74 (AS 5) were associated with a high grain yield, plant spread and plant height. These accessions could be used as potential parents in a breeding program for the development of high-yielding varieties.
Mining Candidate Genes and Favorable Haplotypes for Flag Leaf Shape in Rice (Oryza sativa L.) Based on a Genome-Wide Association Study
Authors: Du Mingyu , Xiong Mengyuan , Chang Yinping , Liu Zhengbo , Wang Rui , Lin Xingxing , Zhou Zhenzhen , Lu Mingwei , Liu Cuiping , Liu Erbao
Published: August 2022

The shape of the rice flag leaf affects rice yield. Therefore, the detection of quantitative trait loci (QTLs) and alleles related to rice flag leaf shape is of great significance for rice yield improvement. Therefore, in 2019 and 2020, we carried out a genome-wide association study of flag leaf length (FLL), flag leaf width (FLW), flag leaf length–width ratio (FLR), and flag leaf area (FLA), considering 1.3 million single-nucleotide polymorphisms (SNPs) in 173 rice accessions, in order to investigate the effects of various genes on flag leaf shape. An abundance of phenotypic variation was found, with respect to the four flag leaf shape parameters of these accessions. We identified one significant SNP position associated with FLL and FLR on chromosome 5 and one significant SNP position associated with FLW on chromosome 2, which were detected in both of the two years of the study period through general linear model (GLM) and mixed linear model (MLM). Furthermore, three candidate genes—LOC_Os02g56760, LOC_Os05g34380, and LOC_Os05g34600—were found to possibly be significantly related to flag leaf shape in rice. Haplotype analysis indicated that LOC_Os05g34380 is highly associated with flag leaf length and flag leaf length–width ratio, LOC_Os05g34600 is highly associated with flag leaf length, and LOC_Os02g56760 is highly associated with flag leaf width. Our results provide important genetic information for the molecular improvement of rice flag leaf shape, laying the foundation for further cloning and molecular-assisted breeding of flag leaf genes.
Study the Effect of Conjugate Novel Ultra-Short Antimicrobial Peptide with Silver Nanoparticles against Methicillin Resistant S. aureus and ESBL E. coli
Authors: Darwish Rula M. , Salama Ali H.
Published: August 2022

Background: Bacterial resistance is a challenging limitation in infection treatment. This work evaluates the potential antibacterial activity of conjugation of Tryasine peptide with silver nanoparticles against selected pathogens. Materials and Methods: The peptide Tryasine was produced using three subunits of tryptophan and three lysine amino acids, then its purity was determined by reverse-phase high-performance liquid chromatography. The peptide was confirmed using mass spectrometry and electrospray ionization mass spectrometry. Silver nanoparticles conjugate with Tryasine was synthesized by adding Tryasine-silver nitrate solution in the presence of the reducing agent sodium borohydride. The presence of Tryasine-silver nanoparticles was indicated by the yellow-brown color and was further confirmed through ultraviolet-visible spectrophotometry. The minimum inhibitory and minimum bactericidal concentrations for Tryasine nanoparticles were determined against Staphylococcus aureus, Escherichia coli, methicillin resistant Staphylococcus aureus, and ESBL Escherichia coli using the microdilution method. Toxicity for nanoparticles conjugated with Tryasine was determined using erythrocyte hemolytic assay. Results: Tryasine alone was effective (MIC around 100 and 200 μM) against standard and resistant strains of bacteria used. However, Tryasine-silver nanoparticles were more effective with MICs ranging from 30 to 100 μM depending on the bacterial strain used. Tryasine-silver nanoparticles at concentration of 100 μM only caused 1% hemolysis on human erythrocytes after 30 min of incubation. Conclusions: The findings indicate that Tryasine-silver nanoparticles had good antibacterial activity against pathogenic strains of Gram-positive and Gram-negative bacteria. Additionally, the conjugate showed low hemolytic activity and cytotoxicity. Therefore, conjugation of Tryasine with silver nanoparticles is a promising treatment candidate for bacterial infection with low toxicity.
Status of Microbiota in Odontogenic Inflammatory Lesions and Dental Surgery Procedures Performed on an Outpatient Basis
Authors: Morawiec Tadeusz , Śmieszek-Wilczewska Joanna , Bogacz Mateusz , Jędrusik-Pawłowska Magdalena , Bubiłek-Bogacz Anna , Mertas Anna
Published: August 2022

Inflammations of the facial part of the skull are most commonly caused by a bacterial infection. They are a frequently occurring pathological process, which results from a rich bacterial flora of the oral cavity, as well as diseased teeth and periodontal tissues. These inflammations have a primarily mixed character with the prevalence of anaerobic bacteria. Gangrene of the dental pulp is the most common odontogenic cause. In the case of inflammations of oral tissues an early and corrective treatment results in quick recovery. The purpose of this work was to assess the efficiency of empirical antibiotic therapy applied in patients with inflammations of oral tissues on the basis of a drug susceptibility profile of bacteria isolated from material extracted from inflammatory lesions. The research material consisted of smears collected from patients with existing acute inflammations in the oral cavity. The smear was collected from the bottom of the lesion after its prior surgical treatment and pus evacuation, and again, 7 days after surgery. In patients with acute odontogenic inflammations the recommended first-line therapy are extended-spectrum penicillins, characterized by a low risk of side effects and strong antimicrobial activity. In the study group, both clindamycin and amoxicillin exhibited high efficiency in treating acute odontogenic inflammatory lesions in the oral cavity.
Antimicrobial Stewardship at Transitions of Care to Outpatient Settings: Synopsis and Strategies
Authors: Liu Elaine , Linder Kristin E. , Kuti Joseph L.
Published: August 2022

Inappropriate antibiotic use and associated consequences, including pathogen resistance and Clostridioides difficile infection, continue to serve as significant threats in the United States, with increasing incidence in the community setting. While much attention has been granted towards antimicrobial stewardship in acute care settings, the transition to the outpatient setting represents a significant yet overlooked area to target optimized antimicrobial utilization. In this article, we highlight notable areas for improved practices and present an interventional approach to stewardship tactics with a framework of disease, drug, dose, and duration. In doing so, we review current evidence regarding stewardship strategies at transitional settings, including diagnostic guidance, technological clinical support, and behavioral and educational approaches for both providers and patients.
Characterization of blaNDM-5-and blaCTX-M-199-Producing ST167 Escherichia coli Isolated from Shared Bikes
Authors: Chen Qiyan , Zou Zhiyu , Cai Chang , Li Hui , Wang Yang , Lei Lei , Shao Bing
Published: August 2022

Shared bikes as a public transport provide convenience for short-distance travel. Whilst they also act as a potential vector for antimicrobial resistant (AR) bacteria and antimicrobial resistance genes (ARGs). However, the understanding of the whole genome sequence of AR strains and ARGs-carrying plasmids collected from shared bikes is still lacking. Here, we used the HiSeq platform to sequence and analyze 24 Escherichia coli isolated from shared bikes around Metro Stations in Beijing. The isolates from shared bikes showed 14 STs and various genotypes. Two blaNDM-5 and blaCTX-M-199-producing ST167 E. coli have 16 resistance genes, four plasmid types and show >95% of similarities in core genomes compared with the ST167 E. coli strains from different origins. The blaNDM-5- or blaCTX-M-199-carrying plasmids sequencing by Nanopore were compared to plasmids with blaNDM-5- or blaCTX-M-199 originated from humans and animals. These two ST167 E. coli show high similarities in core genomes and the plasmid profiles with strains from hospital inpatients and farm animals. Our study indicated that ST167 E. coli is retained in diverse environments and carried with various plasmids. The analysis of strains such as ST167 can provide useful information for preventing or controlling the spread of AR bacteria between animals, humans and environments.
Microglial Activation and Oxidative Stress in PM2.5-Induced Neurodegenerative Disorders
Authors: Song Jie , Han Keyang , Wang Ya , Qu Rongrong , Liu Yuan , Wang Shaolan , Wang Yinbiao , An Zhen , Li Juan , Wu Hui , Wu Weidong
Published: August 2022

Fine particulate matter (PM2.5) pollution remains a prominent environmental problem worldwide, posing great threats to human health. The adverse effects of PM2.5 on the respiratory and cardiovascular systems have been extensively studied, while its detrimental effects on the central nervous system (CNS), specifically neurodegenerative disorders, are less investigated. Neurodegenerative disorders are characterized by reduced neurogenesis, activated microglia, and neuroinflammation. A variety of studies involving postmortem examinations, epidemiological investigations, animal experiments, and in vitro cell models have shown that PM2.5 exposure results in neuroinflammation, oxidative stress, mitochondrial dysfunction, neuronal apoptosis, and ultimately neurodegenerative disorders, which are strongly associated with the activation of microglia. Microglia are the major innate immune cells of the brain, surveilling and maintaining the homeostasis of CNS. Upon activation by environmental and endogenous insults, such as PM exposure, microglia can enter an overactivated state that is featured by amoeboid morphology, the over-production of reactive oxygen species, and pro-inflammatory mediators. This review summarizes the evidence of microglial activation and oxidative stress and neurodegenerative disorders following PM2.5 exposure. Moreover, the possible mechanisms underlying PM2.5-induced microglial activation and neurodegenerative disorders are discussed. This knowledge provides certain clues for the development of therapies that may slow or halt the progression of neurodegenerative disorders induced by ambient PM.
Reverse and Forward Electron Flow-Induced H2O2 Formation Is Decreased in α-Ketoglutarate Dehydrogenase (α-KGDH) Subunit (E2 or E3) Heterozygote Knock Out Animals
Authors: Horváth Gergő , Sváb Gergely , Komlódi Tímea , Ravasz Dora , Kacsó Gergely , Doczi Judit , Chinopoulos Christos , Ambrus Attila , Tretter László
Published: August 2022

α-ketoglutarate dehydrogenase complex (KGDHc), or 2-oxoglutarate dehydrogenase complex (OGDHc) is a rate-limiting enzyme in the tricarboxylic acid cycle, that has been identified in neurodegenerative diseases such as in Alzheimer’s disease. The aim of the present study was to establish the role of the KGDHc and its subunits in the bioenergetics and reactive oxygen species (ROS) homeostasis of brain mitochondria. To study the bioenergetic profile of KGDHc, genetically modified mouse strains were used having a heterozygous knock out (KO) either in the dihydrolipoyl succinyltransferase (DLST+/−) or in the dihydrolipoyl dehydrogenase (DLD+/−) subunit. Mitochondrial oxygen consumption, hydrogen peroxide (H2O2) production, and expression of antioxidant enzymes were measured in isolated mouse brain mitochondria. Here, we demonstrate that the ADP-stimulated respiration of mitochondria was partially arrested in the transgenic animals when utilizing α-ketoglutarate (α-KG or 2-OG) as a fuel substrate. Succinate and α-glycerophosphate (α-GP), however, did not show this effect. The H2O2 production in mitochondria energized with α-KG was decreased after inhibiting the adenine nucleotide translocase and Complex I (CI) in the transgenic strains compared to the controls. Similarly, the reverse electron transfer (RET)-evoked H2O2 formation supported by succinate or α-GP were inhibited in mitochondria isolated from the transgenic animals. The decrease of RET-evoked ROS production by DLST+/− or DLD+/− KO-s puts the emphasis of the KGDHc in the pathomechanism of ischemia-reperfusion evoked oxidative stress. Supporting this notion, expression of the antioxidant enzyme glutathione peroxidase was also decreased in the KGDHc transgenic animals suggesting the attenuation of ROS-producing characteristics of KGDHc. These findings confirm the contribution of the KGDHc to the mitochondrial ROS production and in the pathomechanism of ischemia-reperfusion injury.
Glycolysis and the Pentose Phosphate Pathway Promote LPS-Induced NOX2 Oxidase- and IFN-β-Dependent Inflammation in Macrophages
Authors: Erlich Jonathan R. , To Eunice E. , Luong Raymond , Liong Felicia , Liong Stella , Oseghale Osezua , Miles Mark A. , Bozinovski Steven , Brooks Robert D. , Vlahos Ross , Chan Stanley , O’Leary John J. , Brooks Doug A. , Selemidis Stavros
Published: August 2022

Macrophages undergo a metabolic switch from oxidative phosphorylation to glycolysis when exposed to gram-negative bacterial lipopolysaccharide (LPS), which modulates antibacterial host defence mechanisms. Here, we show that LPS treatment of macrophages increased the classical oxidative burst response via the NADPH oxidase (NOX) 2 enzyme, which was blocked by 2-deoxyglucose (2-DG) inhibition of glycolysis. The inhibition of the pentose phosphate pathway with 6-aminonicotinamide (6-AN) also suppressed the LPS-induced increase in NOX2 activity and was associated with a significant reduction in the mRNA expression of NOX2 and its organizer protein p47phox. Notably, the LPS-dependent enhancement in NOX2 oxidase activity was independent of both succinate and mitochondrial reactive oxygen species (ROS) production. LPS also increased type I IFN-β expression, which was suppressed by 2-DG and 6-AN and, therefore, is dependent on glycolysis and the pentose phosphate pathway. The type I IFN-β response to LPS was also inhibited by apocynin pre-treatment, suggesting that NOX2-derived ROS promotes the TLR4-induced response to LPS. Moreover, recombinant IFN-β increased NOX2 oxidase-dependent ROS production, as well as NOX2 and p47phox expression. Our findings identify a previously undescribed molecular mechanism where both glycolysis and the pentose phosphate pathway are required to promote LPS-induced inflammation in macrophages.
The Relationship between Exercise and Salivary Oxidative Stress: A Systematic Review
Authors: Alves Raphael Charchar Campos , Ferreira Railson Oliveira , Frazão Deborah Ribeiro , de Souza Né Yago Gecy , Mendes Paulo Fernando Santos , Marañón-Vásquez Guido , Royes Luiz Fernando Freire , Fagundes Nathalia Carolina Fernandes , Maia Lucianne Cople , Lima Rafael Rodrigues
Published: August 2022

Salivary content has been reported as a potential biomarker for oxidative stress assessments especially in context of exercise-induced oxidative stress. This systematic review following PRISMA guidelines aimed to evaluate the effects of physical exercise and changes promoted in oxidative stress identified in saliva. Methods: Studies published up to May 2022 were searched in online databases (PubMed, Scopus, Web of Science, The Cochrane Library, LILACS, OpenGrey, and Google Scholar). Risk of bias evaluation were performed using the Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group. Results: A total of 473 references were identified and 22 considered eligible. In this case 14 studies reported increase of antioxidant parameters in saliva while eight studies demonstrated increased lipid peroxidation after exercise. Regarding nitrite levels, two studies showed higher levels after exercise. The quality of evidence was very low due to high heterogeneity, inconsistency and indirectness among studies according Grading of Recommendations, Assessment, Development and Evaluation analysis. Conclusion: Increase of oxidative stress and antioxidant activity in saliva appears to be present after exercise, especially at moderate intensity. However, the wide variety of methods leads to divergent data. For precision in salivary assessments, new research with larger sample sizes and better participant matching are recommended.
Ferroptosis and Its Multifaceted Role in Cancer: Mechanisms and Therapeutic Approach
Authors: Chen Heshu , Wang Chenyu , Liu Zemin , He Xinmiao , Tang Wenjie , He Liuqin , Feng Yanzhong , Liu Di , Yin Yulong , Li Tiejun
Published: August 2022

Ferroptosis, a new type of non-apoptotic cell death modality, is different from other modes of cell death and has been primarily found in tumor cells. Previous studies have reported that ferroptosis can be triggered by specific modulators (e.g., drugs, nutrients, and iron chelators), leading to increased intracellular lipid reactive oxygen species (ROS) accumulation and iron overload. Recent reports have shown that ferroptosis at the cellular and organism levels can prevent an inflammatory storm and cancer development. Emerging evidence suggests potential mechanisms (e.g., system Xc-, glutathione peroxidase 4 (GPX4), lipid peroxidation, glutathione (GSH), and iron chelators) are involved in ferroptosis, which may mediate biological processes such as oxidative stress and iron overload to treat cancer. To date, there are at least three pathways that mediate ferroptosis in cancer cells: system Xc-/GSH/GPX4, FSP1/CoQ10/NAD(P)H, and ATG5/ATG7/NCOA4. Here, we summarize recent advances in the occurrence and development of ferroptosis in the context of cancer, the associations between ferroptosis and various modulators, and the potential mechanisms and therapeutic strategies targeting ferroptosis for the treatment of cancer.
Mitochondria Targeted Antioxidant Significantly Alleviates Preeclampsia Caused by 11β-HSD2 Dysfunction via OPA1 and MtDNA Maintenance
Authors: Long Jing , Huang Yan , Tang Zhengshan , Shan Yali , Feng Dou , Wang Wenqin , Liu Juan , Huang Ying , Gu Hang , Guo Dewei , Yao Ruojin , Ni Xin
Published: August 2022

We have previously demonstrated that placental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) dysfunction contributes to PE pathogenesis. We sought to elucidate molecular mechanisms underlying 11β-HSD2 dysfunction-induced PE and to seek potential therapeutic targets using a 11β-HSD2 dysfunction-induced PE-like rat model as well as cultured extravillous trophoblasts (EVTs) since PE begins with impaired function of EVTs. In 11β-HSD2 dysfunction-induced PE-like rat model, we revealed that placental mitochondrial dysfunction occurred, which was associated with mitDNA instability and impaired mitochondrial dynamics, such as decreased optic atrophy 1 (OPA1) expression. MitoTEMPO treatment significantly alleviated the hallmark of PE-like features and improved mitDNA stability and mitochondrial dynamics in the placentas of rat PE-like model. In cultured human EVTs, we found that 11β-HSD2 dysfunction led to mitochondrial dysfunction and disrupted mtDNA stability. MitoTEMPO treatment improved impaired invasion and migration induced by 11β-HSD2 dysfunction in cultured EVTs. Further, we revealed that OPA1 was one of the key factors that mediated 11β-HSD2 dysfunction-induced excess ROS production, mitochondrial dysfunction and mtDNA reduction. Our data indicates that 11β-HSD2 dysfunction causes mitochondrial dysfunctions, which impairs trophoblast function and subsequently results in PE development. Our study immediately highlights that excess ROS is a potential therapeutic target for PE.
A Novel Signature and Authentication Cryptosystem for Hyperspectral Image by Using Triangular Association Encryption Algorithm in Gyrator Domains
Authors: Yang Zhonglin , Cao Yanhua , Liu Shutian , Tanougast Camel , Blondel Walter , Liu Zhengjun , Chen Hang
Published: August 2022

A novel optical signature and authentication cryptosystem is proposed by applying triangular association encryption algorithm (TAEA) and 3D Arnold transform in Gyrator domains. Firstly, a triangular association encryption algorithm (TAEA) is designed, which makes it possible to turn the diffusion of pixel values within bands into the diffusion within and between bands. Besides, the image signature function is considered and utilized in the proposed cryptosystem. Without the image signature, the original image cannot be restored even if all of the keys are obtained. Moreover, the image integrity authentication function is provided to prevent pixel values from being tampered with. Through the numerical simulation of various types of attacks, the effectiveness and capability of the proposed hyperspectral data signature and authentication cryptosystem is verified.
SuperFormer: Enhanced Multi-Speaker Speech Separation Network Combining Channel and Spatial Adaptability
Authors: Jiang Yanji , Qiu Youli , Shen Xueli , Sun Chuan , Liu Haitao
Published: August 2022

Speech separation is a hot topic in multi-speaker speech recognition. The long-term autocorrelation of speech signal sequences is an essential task for speech separation. The keys are effective intra-autocorrelation learning for the speaker’s speech, modelling the local (intra-blocks) and global (intra- and inter- blocks) dependence features of the speech sequence, with the real-time separation of as few parameters as possible. In this paper, the local and global dependence features of speech sequence information are extracted by utilizing different transformer structures. A forward adaptive module of channel and space autocorrelation is proposed to give the separated model good channel adaptability (channel adaptive modeling) and space adaptability (space adaptive modeling). In addition, at the back end of the separation model, a speaker enhancement module is considered to further enhance or suppress the speech of different speakers by taking advantage of the mutual suppression characteristics of each source signal. Experiments show that the scale-invariant signal-to-noise ratio improvement (SI-SNRi) of the proposed separation network on the public corpus WSJ0-2mix achieves better separation performance compared with the baseline models. The proposed method can provide a solution for speech separation and speech recognition in multi-speaker scenarios.
Effect of Considering Wave Angles on the Motion Response of Oversized Floating Bodies in Offshore Airports under Irregular Wind and Wave Loads
Authors: Wang Lijun , Ke Shitang , Li Wenjie , Chen Jing
Published: August 2022

Most existing studies are based on the hydroelastic response of oversized floating bodies under regular waves, ignoring the effect of wave conditions and incident wave angle on the vibration response of oversized floating bodies in real sea conditions. In this paper, the stability performance of a single module of a mega-floating body at an offshore airport was investigated by using STAR-CCM + numerical simulations based on a specific model, with the introduction of parameters under extreme random wind and wave combined sea conditions. By comparing and analyzing the distribution characteristics of the single module floating body under the action of regular waves and irregular waves, wind, and wave load, and by considering the wave angle along the flow direction, as well as the spreading direction and vertical displacement value under the action of mooring, the overall displacement amplitude of rigid displacement, elastic deformation displacement and considering the influence of both, and the distribution law of motion response along the length of the floating body, we summarize the influence of the wave angle on the dynamic response of an oversized floating body of an offshore airport. The results show that the maximum value of the hydro-elastic response tends to appear at the head and tail of the floating body, the rigid body vertical displacement dominates the role, the amplitude of all displacements of the floating body under the action of the cross wave is larger, and the stress area along the floating body is larger when the wave angle is between 15–30°. The floating body stress value is smaller with angles of 30–65°, and the ability to bear the load is stronger. The hydroelastic response under irregular wave conditions is more sensitive to the wave direction angle, and the elastic deformation has less influence.
Dimensional Changes in Extraction Sockets: A Pilot Study Evaluating Differences between Digital and Conventional Impressions
Authors: Baek Min-Woo , Lim Hyun-Chang , Noh Kwantae , Choi Seong-Ho , Lee Dong-Woon
Published: August 2022

Traditionally, soft tissue records are obtained by dental impression using impression materials; however, accurately recording the soft tissue immediately after tooth extraction is difficult. We measured the tissue changes after tooth extraction and compared two impression modalities (digital versus conventional) by measuring the changes at the soft tissue level. In this case, 15 patients with 17 single extraction sites were enrolled. Conventional impression (CI) using vinyl polysiloxane material and digital impression (DI) using an intraoral scanner were prepared immediately after extraction (T0) and at 2 months post-extraction (T1). Standard tessellation language files were generated for superimposition of the tissue surface. The tissue changes and discrepancies were measured on the superimposed surfaces. The differences in the changes and the discrepancy between the tissue surface impression at each time point were compared. At all measuring levels, the total tissue change was significantly different between groups DI and CI (p < 0.05). DI exhibited a more pronounced tissue surface at both time points, and the total discrepancy was statistically significantly greater at T0 than at T1 (p < 0.05). The values from DI and CI demonstrated small but significantly different for the same study material. The interpretation of such differences may depend on the clinical situation or scientific value.
Aronia Extracts in the Production of Confectionery Masses
Authors: Ghendov-Mosanu Aliona , Ungureanu-Iuga Mădălina , Mironeasa Silvia , Sturza Rodica
Published: August 2022

The article examines the opportunity to use extracts and Aronia melanocarpa (Michx.) Elliot fruit powders in the production of sugar confectionery for the substitution of synthetic dyes. In the technology of manufacturing confectionery masses, synthetic dyes are used that can cause various allergic reactions, as well as hyperactivity syndrome and lack of concentration in children. The composition of hydroalcoholic extracts was analyzed, and the metabolites of polyphenols, individual anthocyanins and organic acids were quantified. Antioxidant capacity and CIELab chromatic parameters were tested. The technology for manufacturing confectionary masses with extract and powder of aronia was developed. The sensory profile, physicochemical and microbiological quality parameters, antioxidant activity and color characteristics of the confectionary masses with the extract and powder of aronia addition were determined on the 1st and 50th day from the production date. The evolution of DPPH antioxidant activity of confectionery masses during storage was measured in vitro, in the conditions of gastric digestion. The results showed that Aronia melanocarpa (Michx.) Elliot extract is rich in polyphenols, flavonoids and tannins, the main organic acids being represented by malic, citric, acetic and ascorbic acid. During the 50th storage day, the antioxidant activity was higher in confectionery masses containing aronia compared to the control. The sensory and microbiological testing of confectionary masses demonstrated that the combination of extract and aronia powder ensures the optimal shelf life and organoleptic scores. It was demonstrated that during the storage of confectionery masses with aronia, the physicochemical indicators of quality were in accordance with the regulated admissible values. Positive effects of aronia were observed on confectionery masses’ color saturation. These results underline the opportunity to use aronia extract and/or powder in confectionery industry to replace synthetic dyes and obtain products with enhanced functionality.