bluuebunny/crossref_metadata_2025 huggingface dataset:
UPLC-ESI-QTRAP-MS/MS Analysis to Quantify Bioactive Compounds in Fennel (Foeniculum vulgare Mill.) Waste with Potential Anti-Inflammatory Activity
Authors: Crescenzi Maria Assunta , D’Urso Gilda , Piacente Sonia , Montoro Paola
Published: July 2022

Foeniculum vulgare is a perennial aromatic plant whose cultivation produces large amounts of waste rich in bioactive compounds with promising anti-inflammatory activities. Nine selected metabolites were quantified through Ultra Performance Liquid Chromatography (UPLC) hyphenated to QTRAP mass spectrometry by using MRM (multiple reaction monitoring) was performed on four parts of fennel: bulb, stem, little stem, and leaf. Analysis revealed significant differences in the amount of quantified metabolites, suggesting that little stem and leaf are the most valuable parts of the waste. Phenolic acids and glycosylated flavonoids were quantified for their known possible anti-inflammatory activities; in fact, due to this reason their ability to inhibit COX-1 and COX-2 isoforms was evaluated through a fluorometric assay, resulting in specific inhibitors of COX-2 at certain concentrations. In conclusion, as the leaf of fennel may be beneficial to human health, clinical studies should include it in nutraceuticals or functional foods for human consumption.
Electrochemical Characterization of Nanoporous Alumina-Based Membranes with Different Structure and Geometrical Parameters by Membrane Potential Analysis
Authors: Romero Virginia , Benavente Juana
Published: July 2022

Electrochemical characterization of alumina-based membranes obtained by two different techniques, sinterization or anodization, is performed by analyzing membrane potential values. This analysis allows us the estimation of the effective concentration of fixed charge in the membrane (Xef) and the transport number of the ions into the pores (ti), as well as the determination of ionic permselectivity (P(i)) and their correlation with the different structures (supported, symmetrical or asymmetric), geometrical parameters (pore size and porosity) and surface materials (alumina-zirconia or alumina) of the studied membranes. From these results, the electropositive character of the membranes was stated, but also the significant reduction (70%) in Xef value and around 30% in permselectivity when pore size increases from 25 nm to 100 nm, in the case of sinterized alumina-zirconia membranes with similar porosity (CRF samples), while the clear influence of pore size on the electrochemical behavior of the electrochemically synthesized alumina membranes (NPAM samples) was confirmed as well as the lower influence of membrane porosity. Moreover, the effect of protein (BSA) static fouling on electrochemical parameters for both CRF and NPAMs samples was also analyzed, and our results show a reduction in the electropositive character of both membranes, being this behavior opposite to that discussed for one of the NPAMs as a result of surface modification with a theophylline derivative (Theo 1).
Nontuberculous Mycobacteria: Ecology and Impact on Animal and Human Health
Authors: Pavlik Ivo , Ulmann Vit , Falkinham Joseph O.
Published: July 2022

Nontuberculous mycobacteria (NTM) represent an important group of environmentally saprophytic and potentially pathogenic bacteria that can cause serious mycobacterioses in humans and animals. The sources of infections often remain undetected except for soil- or water-borne, water-washed, water-based, or water-related infections caused by groups of the Mycobacterium (M.) avium complex; M. fortuitum; and other NTM species, including M. marinum infection, known as fish tank granuloma, and M. ulcerans infection, which is described as a Buruli ulcer. NTM could be considered as water-borne, air-borne, and soil-borne pathogens (sapronoses). A lot of clinically relevant NTM species could be considered due to the enormity of published data on permanent, periodic, transient, and incidental sapronoses. Interest is currently increasing in mycobacterioses diagnosed in humans and husbandry animals (esp. pigs) caused by NTM species present in peat bogs, potting soil, garden peat, bat and bird guano, and other matrices used as garden fertilizers. NTM are present in dust particles and in water aerosols, which represent certain factors during aerogenous infection in immunosuppressed host organisms during hospitalization, speleotherapy, and leisure activities. For this Special Issue, a collection of articles providing a current view of the research on NTM—including the clinical relevance, therapy, prevention of mycobacterioses, epidemiology, and ecology—are addressed.
Biosurfactant from Bacillus subtilis DS03: Properties and Application in Cleaning Out Place System in a Pilot Sausages Processing
Authors: Cruz Mendoza Iana , Villavicencio-Vasquez Mirian , Aguayo Paola , Coello Montoya Diana , Plaza Luis , Romero-Peña María , Marqués Ana M. , Coronel-León Jonathan
Published: July 2022

Biosurfactants (BS) are amphiphilic molecules that align at the interface reducing the surface tension. BS production is developed as an alternative to synthetic surfactants because they are biodegradable, with low toxicity and high specificity. BS are versatile, and this research proposes using a biosurfactant crude extract (BCE) as part of cleaning products. This paper reported the BCE production from Bacillus subtilis DS03 using a medium with molasses. The BCE product was characterized by different physical and chemical tests under a wide pH range, high temperatures, and emulsifying properties showing successful results. The water surface tension of 72 mN/m was reduced to 34 mN/m with BCE, achieving a critical micelle concentration at 24.66 ppm. BCE was also applied to polystyrene surface as pre-treatment to avoid microbial biofilm development, showing inhibition in more than 90% of Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes above 2000 ppm BCE. The test continued using BCE as post-treatment to remove biofilms, reporting a significant reduction of 50.10% Escherichia coli, 55.77% Staphylococcus aureus, and 59.44% Listeria monocytogenes in a concentration higher than 250 ppm BCE. Finally, a comparison experiment was performed between sodium lauryl ether sulfate (SLES) and BCE (included in commercial formulation), reporting an efficient reduction with the mixtures. The results suggested that BCE is a promising ingredient for cleaning formulations with applications in industrial food applications.
A Novel Antimicrobial Metabolite Produced by Paenibacillus apiarius Isolated from Brackish Water of Lake Balkhash in Kazakhstan
Authors: Meene Alexander , Herzer Christiane , Schlüter Rabea , Zayadan Bolatkhan , Pukall Ruediger , Schumann Peter , Schauer Frieder , Urich Tim , Mikolasch Annett
Published: July 2022

Four aerobic bacteria with bacteriolytic capabilities were isolated from the brackish water site Strait Uzynaral of Lake Balkhash in Kazakhstan. The morphology and physiology of the bacterial isolates have subsequently been analyzed. Using matrix assisted laser desorption ionization-time of flight mass spectrum and partial 16S rRNA gene sequence analyses, three of the isolates have been identified as Pseudomonas veronii and one as Paenibacillus apiarius. We determined the capability of both species to lyse pre-grown cells of the Gram-negative strains Pseudomonas putida SBUG 24 and Escherichia coli SBUG 13 as well as the Gram-positive strains Micrococcus luteus SBUG 16 and Arthrobacter citreus SBUG 321 on solid media. The bacteriolysis process was analyzed by creating growth curves and electron micrographs of co-cultures with the bacteriolytic isolates and the lysis sensitive strain Arthrobacter citreus SBUG 321 in nutrient-poor liquid media. One metabolite of Paenibacillus apiarius was isolated and structurally characterized by various chemical structure determination methods. It is a novel antibiotic substance.
The Difference in the Bacterial Attachment among Pratylenchus neglectus Populations and Its Effect on the Nematode Infection
Authors: Nuaima Rasha Haj
Published: July 2022

Different bacterial isolates attach to the cuticle of plant-parasitic nematodes, affecting their interactions with the host plant. Nematode populations differ in their genetic and cuticle structures, causing variable interactions with host plants and natural enemies. In the current study, attachment assays were carried out to compare the attachment of soil bacteria in general and the bacterial isolate of Rothia sp. in particular among geographically diverse populations of Pratylenchus neglectus. Biological and molecular assays were further conducted to examine the effect of Rothia attachment on nematode penetration into barley roots and to sequence the fatty acid- and retinol-binding gene (Pn-far-1). The results showed that nematode populations of P. neglectus differed in their bacterial attachment. Soil bacteria and Rothia sp. attached specifically to the cuticle of P. neglectus and did so differently among the nematode populations. Rothia attachment caused a reduction in the infectivity of three nematode populations in barley roots. The sequencing of the far-1 gene revealed genetic variability within and among P. neglectus populations. In conclusion, the interaction between P. neglectus and their bacterial attachers occurs in a population-specific manner, elucidating an essential aspect of using biological agents to manage plant-parasitic nematodes. Key Message: 1. Geographically diverse populations of the root lesion nematode Pratylenchus neglectus differed in the soil bacterial communities attached to their cuticles. 2. The bacterial isolate of Rothia sp. attached to the cuticle of P. neglectus and reduced its penetration into the host plant in a population-specific manner. 3. The fatty acid- and retinol-binding gene (far-1) varied within and among P. neglectus populations with their different bacterial attachment.
The Impact of Antimicrobial Stewardship Training on Calf Producers’ Knowledge, Treatment Behaviors and Quantified Antimicrobial Use
Authors: Pempek Jessica , Masterson Martey , Portillo-Gonzalez Rafael , Creutzinger Kate , Cheng Ting-Yu , Habing Greg
Published: July 2022

The judicious use of antimicrobials on farms is necessary to mitigate the development of antimicrobial-resistant pathogens that compromise human and animal health. On livestock farms, veterinarians prescribe and dispense antimicrobials, but producers use rapid judgements of disease severity to make routine decisions on the initiation of empirical antimicrobial therapy. Therefore, the knowledge and skills required to accurately diagnose treatable bacterial infections is necessary for optimal antimicrobial stewardship. Veal calves often undergo stressors and environmental exposures that increase calves’ risk of bacterial infections, and antimicrobials are sometimes necessary to ensure their health. The objective of this trial was to measure the impact of antimicrobial stewardship training on calf producers’ knowledge of antimicrobial stewardship, accuracy of identifying calves for treatment, and quantified antimicrobial use. Eight farms were evenly allocated into either intervention or control groups. Training resulted in both higher scores on assessments and higher sensitivity for detecting cases that required antimicrobial therapy relative to a veterinarian. Importantly, there was a 50% reduction in the antimicrobial dosing rate among intervention farms relative to control farms. Antimicrobial stewardship training among calf producers was effective at changing producers’ behaviors and reducing antimicrobial use.
Effect of Gut Microbiota-Derived Metabolites on Immune Checkpoint Inhibitor Therapy: Enemy or Friend?
Authors: Zhao Haobin , Wang Di , Zhang Zhifu , Xian Junfang , Bai Xiaosu
Published: July 2022

The human gut is inhabited by hundreds of billions of commensal microbiota that collectively produce thousands of small molecules and metabolites with local and systemic effects on the physiology of the host. Much evidence from preclinical to clinical studies has gradually confirmed that the gut microbiota can regulate anti-tumor immunity and affect the efficacy of cancer immune checkpoint inhibitors (ICIs) therapy. In particular, one of the main modes of gut microbiota regulating anti-tumor immunity is through metabolites, which are small molecules that can be transported in the body and act on local and systemic anti-tumor immune responses to promote ICIs immunotherapy efficacy. We discuss the functions of microbial metabolites in humans, focusing on the effects and mechanisms of microbial metabolites on immunotherapy, and analyze their potential applications as immune adjuvants and therapeutic targets to regulate immunity and enhance ICIs. In summary, this review provides the basis for the rational design of microbiota and microbial metabolite-based strategies of enhancing ICIs.
Hesperidin Exhibits Protective Effects against PM2.5-Mediated Mitochondrial Damage, Cell Cycle Arrest, and Cellular Senescence in Human HaCaT Keratinocytes
Authors: Herath Herath Mudiyanselage Udari Lakmini , Piao Mei Jing , Kang Kyoung Ah , Zhen Ao Xuan , Fernando Pincha Devage Sameera Madushan , Kang Hee Kyoung , Yi Joo Mi , Hyun Jin Won
Published: July 2022

Particulate matter 2.5 (PM2.5) exposure can trigger adverse health outcomes in the human skin, such as skin aging, wrinkles, pigment spots, and atopic dermatitis. PM2.5 is associated with mitochondrial damage and the generation of reactive oxygen species (ROS). Hesperidin is a bioflavonoid that exhibits antioxidant and anti-inflammatory properties. This study aimed to determine the mechanism underlying the protective effect of hesperidin on human HaCaT keratinocytes against PM2.5-induced mitochondrial damage, cell cycle arrest, and cellular senescence. Human HaCaT keratinocytes were pre-treated with hesperidin and then treated with PM2.5. Hesperidin attenuated PM2.5-induced mitochondrial and DNA damage, G0/G1 cell cycle arrest, and SA-βGal activity, the protein levels of cell cycle regulators, and matrix metalloproteinases (MMPs). Moreover, treatment with a specific c-Jun N-terminal kinase (JNK) inhibitor, SP600125, along with hesperidin markedly restored PM2.5-induced cell cycle arrest and cellular senescence. In addition, hesperidin significantly reduced the activation of MMPs, including MMP-1, MMP-2, and MMP-9, by inhibiting the activation of activator protein 1. In conclusion, hesperidin ameliorates PM2.5-induced mitochondrial damage, cell cycle arrest, and cellular senescence in human HaCaT keratinocytes via the ROS/JNK pathway.
A Novel Turn-On Fluorescence Probe Based on Cu(II) Functionalized Metal–Organic Frameworks for Visual Detection of Uric Acid
Authors: Yang Jie , Che Jie , Jiang Xin , Fan Yangchun , Gao Daojiang , Bi Jian , Ning Zhanglei
Published: July 2022

As an important biomarker in urine, the level of uric acid is of importance for human health. In this work, a Cu(II) functionalized metal–organic framework (Cu2+@Tb-MOFs) is designed and developed as a novel fluorescence probe for wide-range uric acid detection in human urine. The study shows that this fluorescence platform demonstrated excellent pH-independent stability, high water tolerance, and good thermal stability. Based on the strong interaction between metal ions and uric acid, the designed Cu2+@Tb-MOFs can be employed as efficient turn-on fluorescent probes for the detection of uric acid with wide detection range (0~104 µM) and high sensitivity (LOD = 0.65 µM). This probe also demonstrates an anti-interference property, as other species coexisted, and the possibility for recycling. The sensing mechanisms are further discussed at length. More importantly, we experimentally constructed a molecular logic gate operation based on this fluorescence probe for intelligent detection of uric acid. These results suggest the Cu(II) functionalized metal–organic framework can act as a prominent candidate for personalized monitoring of the concentration of uric acid in the human urine system.
Small Molecular Drug Screening Based on Clinical Therapeutic Effect
Authors: Zhong Cai , Ai Jiali , Yang Yaxin , Ma Fangyuan , Sun Wei
Published: July 2022

Virtual screening can significantly save experimental time and costs for early drug discovery. Drug multi-classification can speed up virtual screening and quickly predict the most likely class for a drug. In this study, 1019 drug molecules with actual therapeutic effects are collected from multiple databases and documents, and molecular sets are grouped according to therapeutic effect and mechanism of action. Molecular descriptors and molecular fingerprints are obtained through SMILES to quantify molecular structures. After using the Kennard–Stone method to divide the data set, a better combination can be obtained by comparing the combined results of five classification algorithms and a fusion method. Furthermore, for a specific data set, the model with the best performance is used to predict the validation data set. The test set shows that prediction accuracy can reach 0.862 and kappa coefficient can reach 0.808. The highest classification accuracy of the validation set is 0.873. The more reliable molecular set has been found, which could be used to predict potential attributes of unknown drug compounds and even to discover new use for old drugs. We hope this research can provide a reference for virtual screening of multiple classes of drugs at the same time in the future.
Metabolic and Proteomic Analysis of Chlorella sorokiniana, Chloroidium saccharofilum, and Chlorella vulgaris Cells Cultured in Autotrophic, Photoheterotrophic, and Mixotrophic Cultivation Modes
Authors: Piasecka Agata , Baier Andrea
Published: July 2022

Chlorella is one of the most well-known microalgal genera, currently comprising approximately a hundred species of single-celled green algae according to the AlgaeBase. Strains of the genus Chlorella have the ability to metabolize both inorganic and organic carbon sources in various trophic modes and synthesize valuable metabolites that are widely used in many industries. The aim of this work was to investigate the impact of three trophic modes on the growth parameters, productivities of individual cell components, and biochemical composition of Chlorella sorokiniana, Chloroidium saccharofilum, and Chlorella vulgaris cells with special consideration of protein profiles detected by SDS-PAGE gel electrophoresis and two-dimensional gel electrophoresis with MALDI-TOF/TOF MS. Mixotrophic conditions with the use of an agro-industrial by-product stimulated the growth of all Chlorella species, which was confirmed by the highest specific growth rates and the shortest biomass doubling times. The mixotrophic cultivation of all Chlorella species yielded a high amount of protein-rich biomass with reduced contents of chlorophyll a, chlorophyll b, carotenoids, and carbohydrates. Additionally, this work provides the first information about the proteome of Chloroidium saccharofilum, Chlorella sorokiniana, and Chlorella vulgaris cells cultured in molasses supplementation conditions. The proteomic analysis of the three Chlorella species growing photoheterotrophically and mixotrophically showed increased accumulation of proteins involved in the cell energy metabolism and carbon uptake, photosynthesis process, and protein synthesis, as well as proteins involved in intracellular movements and chaperone proteins.
Plants as a Source of Anticancer Agents: From Bench to Bedside
Authors: Talib Wamidh H. , Daoud Safa , Mahmod Asma Ismail , Hamed Reem Ali , Awajan Dima , Abuarab Sara Feras , Odeh Lena Hisham , Khater Samar , Al Kury Lina T.
Published: July 2022

Cancer is the second leading cause of death after cardiovascular diseases. Conventional anticancer therapies are associated with lack of selectivity and serious side effects. Cancer hallmarks are biological capabilities acquired by cancer cells during neoplastic transformation. Targeting multiple cancer hallmarks is a promising strategy to treat cancer. The diversity in chemical structure and the relatively low toxicity make plant-derived natural products a promising source for the development of new and more effective anticancer therapies that have the capacity to target multiple hallmarks in cancer. In this review, we discussed the anticancer activities of ten natural products extracted from plants. The majority of these products inhibit cancer by targeting multiple cancer hallmarks, and many of these chemicals have reached clinical applications. Studies discussed in this review provide a solid ground for researchers and physicians to design more effective combination anticancer therapies using plant-derived natural products.
Palladium-Doped Single-Walled Carbon Nanotubes as a New Adsorbent for Detecting and Trapping Volatile Organic Compounds: A First Principle Study
Authors: Yoosefian Mehdi , Ayoubi Elaheh , Atanase Leonard Ionut
Published: July 2022

Volatile organic compounds (VOCs) are in the vapor state in the atmosphere and are considered pollutants. Density functional theory (DFT) calculations with the wb97xd exchange correlation functional and the 6-311+G(d,p) basis set are carried out to explore the potential possibility of palladium-doped single-walled carbon nanotubes (Pd/SWCNT-V), serving as the resource for detecting and/or adsorbing acetonitrile (ACN), styrene (STY), and perchloroethylene (PCE) molecules as VOCs. The suggested adsorbent in this study is discussed with structural parameters, frontier molecular orbital theory, molecular electrical potential surfaces (MEPSs), natural bond orbital (NBO) analyses, and the density of states. Furthermore, following the Bader theory of atoms in molecules (AIM), the topological properties of the electron density contributions for intermolecular interactions are analyzed. The obtained results show efficient VOC loading via a strong chemisorption process with a mean adsorption energy of −0.94, −1.27, and −0.54 eV for ACN, STY, and PCE, respectively. Our results show that the Pd/SWCNT-V can be considered a good candidate for VOC removal from the environment.
Citicoline Modifies the Expression of Specific miRNAs Related to Cardioprotection in Patients with ST-Segment Elevation Myocardial Infarction Subjected to Coronary Angioplasty
Authors: Silva-Palacios Alejandro , Arroyo-Campuzano Miguel , Flores-García Mirthala , Patlán Mariana , Hernández-Díazcouder Adrián , Alcántara Diego , Ramírez-Camacho Ixchel , Arana-Hidalgo Dana , Soria-Castro Elizabeth , Sánchez Fausto , González-Pacheco Héctor , Zazueta Cecilia
Published: July 2022

Extracellular vesicles are recognized as signaling mediators between cells both in physiological and pathological communication. In this work, we explored the potential effect of citicoline to modify relevant proteins or miRNAs for cardioprotection in the smallest population of such microvesicles; i.e., in exosomes from patients diagnosed with ST-segment elevation myocardial infarction (STEMI) undergoing coronary angioplasty. The plasma-exosome-enriched fraction from these patients was characterized. Their cellular origin was assessed by flow cytometry and Western blot, whereas miRNA expression was evaluated by real-time polymerase chain reaction (qRT-PCR). The content of caveolin-1, caveolin-3, and hnRNPA2B1, which play a relevant role in selective transport of miRNAs into microvesicles, along with the effect on cell viability of the exosomes obtained from citicoline-treated and untreated groups were also analyzed. Our results showed that hypoxic stress increases exosome release into the circulation. Moreover, we found that CD146+ increased in exosomes from citicoline-treated patients, while CD142+ decreased in these patients compared to the placebo group. No changes were detected in the protein levels of caveolin-1, caveolin-3, and hnRNPA2B1. Citicoline administration modified the expression of miR233-3p, miR92, and miR21-5p in exosomes. Cell viability decreased in the presence of exosomes from infarcted patients, while incubation of H9c2 cells with exosomes from patients reperfused with citicoline did not affect cell viability. In conclusion, citicoline administration modifies the expression of specific miRNAs related to cardioprotection in exosomes.
Experimental Studies Indicate That ST-2223, the Antagonist of Histamine H3 and Dopamine D2/D3 Receptors, Restores Social Deficits and Neurotransmission Dysregulation in Mouse Model of Autism
Authors: Eissa Nermin , Venkatachalam Karthikkumar , Jayaprakash Petrilla , Yuvaraju Priya , Falkenstein Markus , Stark Holger , Sadek Bassem
Published: July 2022

Altered regulation of neurotransmitters may lead to many pathophysiological changes in brain disorders including autism spectrum disorder (ASD). Given the fact that there are no FDA-approved effective treatments for the social deficits in ASD, the present study determined the effects of chronic systemic treatment of the novel multiple-active H3R/D2R/D3R receptor antagonist ST-2223 on ASD-related social deficits in a male Black and Tan Brachyury (BTBR) mice. ST-2223 (2.5, 5, and 10 mg/kg, i.p.) significantly and dose-dependently mitigated social deficits and disturbed anxiety levels of BTBR mice (p < 0.05) in comparison to the effects of aripiprazole (1 mg/kg, i.p.). Moreover, levels of monoaminergic neurotransmitters quantified by LC-MS/MS in four brain regions including the prefrontal cortex, cerebellum, striatum, and hippocampus unveiled significant elevation of histamine (HA) in the cerebellum and striatum; dopamine (DA) in the prefrontal cortex and striatum; as well as acetylcholine (ACh) in the prefrontal cortex, striatum, and hippocampus following ST-2223 (5 mg/kg) administration (all p < 0.05). These in vivo findings demonstrate the mitigating effects of a multiple-active H3R/D2R/D3R antagonist on social deficits of assessed BTBR mice, signifying its pharmacological potential to rescue core ASD-related behaviors and altered monoaminergic neurotransmitters. Further studies on neurochemical alterations in ASD are crucial to elucidate the early neurodevelopmental variations behind the core symptoms and heterogeneity of ASD, leading to new approaches for the future therapeutic management of ASD.
Smartphone Based Fluorescence Imaging for Online Control of Cattle Fodder Preparation
Authors: Lednev Vasily N. , Kucherenko Ivan A. , Levshin Vladislav A. , Sdvizhenskii Pavel A. , Grishin Mikhail Ya. , Dorohov Alexey S. , Pershin Sergey M.
Published: July 2022

A simple and cost-effective technique has been suggested for online monitoring of grist concentration in fodder. The technique is based on fluorescence imaging with grow light lamp excitation and a consumer CMOS camera (DSLR or smartphone) for photo capturing. A prototype instrument has been developed and tested in the laboratory for quantitative express determination of rapeseed grist concentration in fodder. In situ measurement of grist concentration during cattle food preparation has been demonstrated, and the perspectives were discussed. The developed instrument has the potential to ensure more accurate preparation of individual cattle diets compared to currently available methods, which will improve the efficiency of the cattle food production.
Molybdenum Oxide Functional Passivation of Aluminum Dimers for Enhancing Optical-Field and Environmental Stability
Authors: Lorenzo Daniela , Riminucci Fabrizio , Manoccio Mariachiara , Balestra Gianluca , Simeone Daniela , Tobaldi David Maria , Esposito Marco , Passaseo Adriana , Tasco Vittorianna , Cuscunà Massimo
Published: July 2022

In this contribution, we present an experimental and numerical study on the coating of Al plasmonic nanostructures through a conformal layer of high-refractive-index molybdenum oxide. The investigated structures are closely coupled nanodisks where we observe that the effect of the thin coating is to help gap narrowing down to the sub-5-nm range, where a large electromagnetic field enhancement and confinement can be achieved. The solution represents an alternative to more complex and challenging lithographic approaches, and results are also advantageous for enhancing the long-term stability of aluminum nanostructures.
Comparative Transcriptome Analysis of Grafted Tomato with Drought Tolerance
Authors: Fuentes-Merlos Maria Isabel , Bamba Masaru , Sato Shusei , Higashitani Atsushi
Published: July 2022

Grafting is a method used in agriculture to improve crop production and tolerance to biotic and abiotic stress. This technique is widely used in tomato, Solanum lycopersicum L.; however, the effects of grafting on changes in gene expression associated with stress tolerance in shoot apical meristem cells are still under-discovered. To clarify the effect of grafting, we performed a transcriptomic analysis between non-grafted and grafted tomatoes using the tomato variety Momotaro-scion and rootstock varieties, TD1, GS, and GF. Drought tolerance was significantly improved not only by a combination of compatible resistant rootstock TD1 but also by self-grafted compared to non-grafted lines. Next, we found the differences in gene expression between grafted and non-grafted plants before and during drought stress treatment. These altered genes are involved in the regulation of plant hormones, stress response, and cell proliferation. Furthermore, when comparing compatible (Momo/TD1 and Momo/Momo) and incompatible (Momo/GF) grafted lines, the incompatible line reduced gene expression associated with phytohormones but increased in wounding and starvation stress-response genes. These results conclude that grafting generates drought stress tolerance through several gene expression changes in the apical meristem.
Polycyclic Aromatic Hydrocarbons in Araucaria heterophylla Needles in Urban Areas: Evaluation of Sources and Road Characteristics
Authors: Alexandrino Katiuska , Sánchez Nazly E. , Zalakeviciute Rasa , Acuña Wilber , Viteri Fausto
Published: July 2022

Araucaria heterophylla needles were collected in urban areas of the city of Quito, Ecuador, to analyze the relationship between the concentration of polycyclic aromatic hydrocarbons (PAHs) with different emission sources and road characteristics. The PAHs were analyzed by high-performance liquid chromatography (HPLC) and included naphthalene (Naph), benzo[a]anthracene (BaA), chrysene (Chry), and benzo[a]pyrene (BaP), which are related to the sources considered in this work. The results indicated that some streets with moderate and low traffic intensity had higher total concentrations of PAHs than streets with high traffic intensity, showing the importance of non-traffic related emission sources and road characteristics on PAH emissions. All the studied PAHs were associated with traffic emissions, although Naph and BaP were more associated with acceleration and braking activities, while BaA and Chry also seemed to come from restaurant emissions. The presence of gas stations was also important in the emission of PAHs. Road capacity seems to have a higher effect on pollutant emission than road gradient and urban forms. The outcomes of this study are expected to facilitate the diagnostics of the concentration of PAHs in urban areas, which contribute to the design of strategies for the mitigation of pollution by PAHs in urban environment.
Testing of Rubber Composites Reinforced with Carbon Nanotubes
Authors: Bakošová Dana , Bakošová Alžbeta
Published: July 2022

Carbon nanotubes (CNTs) have attracted growing interest as a filler in rubber nanocomposites due to their mechanical and electrical properties. In this study, the mechanical properties of a NR/BR/IR/SBR compound reinforced with single-wall carbon nanotubes (SWCNTs) were investigated using atomic force microscopy (AFM), tensile tests, hardness tests, and a dynamical mechanical analysis (DMA). The tested materials differed in SWCNT content (1.00–2.00 phr) and were compared with a reference compound without the nanofiller. AFM was used to obtain the topography and spectroscopic curves based on which local elasticity was characterized. The results of the tensile and hardness tests showed a reinforcing effect of the SWCNTs. It was observed that an addition of 2.00 phr of the SWCNTs resulted in increases in tensile strength by 9.5%, Young’s modulus by 15.44%, and hardness by 11.18%, while the elongation at break decreased by 8.39% compared with the reference compound. The results of the temperature and frequency sweep DMA showed higher values of storage and loss moduli, as well as lower values of tangent of phase angle, with increasing SWCNT content.
Modeling 3D Droplet Movement Using a Drop-on-Demand Inkjet Printhead Model
Authors: Tofan Tim , Borodinas Sergejus , Kačianauskas Rimantas , Jasevičius Raimondas
Published: July 2022

This article presents a numerical simulation of a printhead model for drop-on-demand (DoD) inkjet printers. A three-dimensional droplet model is provided for the numerical study of inks, ejection parameters, droplet movement, and the analysis of droplet impacts on the surface. This work is devoted to the analysis of different droplet ejection settings during the printing process, when the behavior of the droplet directly affects the accuracy of the printing process itself. A numerical model was also developed to investigate the effect of various settings on droplet stability, including printhead size and nozzle orifice, motion parameters (pulse strength and droplet ejection amplitude) and fluid properties. The results reflect the behavior of the ink droplet over time. The behavior of the drop was tested at different waveform ejection parameters and a mass turnover was observed.
Performance, Emission and Combustion Characteristics of a VCR Engine Fueled with Sea Mango Biodiesel/Diesel Blends
Authors: Renish R. Rohith , Selvam Amala Justus , Čep Robert , Elangovan Muniyandy
Published: July 2022

The constant emission of greenhouse gases into the atmosphere, due to the continuous burning of fossil fuels, has been driving researchers to develop an environmentally friendly alternative fuel solution. An experimental investigation was conducted on a laboratory scale, to evaluate the physicochemical qualities, performance, emissions, and combustion characteristics of sea mango oil biodiesel blends and pure diesel fuel on a single-cylinder, variable compression ratio (VCR) engine. Tests were conducted at 1500 rpm, 210 bar, and 23° bTDC, under varying loading circumstances of 0, 3, 6, 9, and 12 kgs, and compression ratios 16:1, 17:1, and 18:1, respectively. The findings revealed that higher compression ratios (CRs) improve the performance, emission, and combustion characteristics of an engine. At CR 18:1, BTHE, SFC, and EGT improved by 8.78%, 11.18%, and 2.52% more than the standard compression ratio (17:1). The CO, HC, and smoke emissions also lowered by 14.65%, 18.56%, and 11.56%, respectively, at CR 18:1. The NOx emissions increased by 6.77%. The combustion characteristics also improved, with an increase in the CR. The findings of this investigation show that sea mango biodiesel blends can be used as a diesel alternative at CR 18:1, with no engine modifications.
Ionic Polyacrylamides as Stability-Modifying Substances of Soil Mineral Suspensions Containing Heavy Metal Impurities
Authors: Wiśniewska Małgorzata , Fijałkowska Gracja , Szewczuk-Karpisz Katarzyna , Herda Karolina , Chibowski Stanisław
Published: July 2022

The accumulation of heavy metal in soils is a serious environmental problem. The aim of this paper was to compare the adsorption mechanism of ionic polyacrylamides (PAMs)—anionic and cationic with different contents of functional groups, on the surface of clay minerals—montmorillonite (type 2:1) and kaolinite (type 1:1), without and with the presence of heavy metal ions (Cr(VI) or Pb(II)). The dependence of solution pH, structure of mineral, type of PAM, ionic form of heavy metal, as well as order of adsorbates addition on the adsorption efficiency and stability of the clay mineral-polymer-heavy metal system was determined. In addition to adsorption and stability studies, electrokinetic and potentiometric titration measurements were performed. It was shown that the mixed PAM+heavy metal adsorption layers modify the surface properties of clay minerals significantly, which in many cases leads to the effective destabilization of the solid suspension and its separation from the liquid phase. Moreover, the most important factor, which influences the adsorbed amount of ionic polyacrylamide, turned out to be the internal structure of layered aluminosilicates and the presence of inter-package spaces capable of adsorbate molecules accumulating. For this reason the obtained adsorption capacity of montmorillonite is about 100 times higher in comparison to kaolinite.
Optical Emission Spectroscopy of Underwater Spark Generated by Pulse High-Voltage Discharge with Gas Bubble Assistant
Authors: Stelmashuk Vitaliy , Prukner Vaclav , Kolacek Karel , Tuholukov Andrii , Hoffer Petr , Straus Jaroslav , Frolov Oleksandr , Jirasek Vit
Published: July 2022

This paper is aimed at the investigation of the acoustic and spectral characteristics of underwater electric sparks generated between two plate electrodes, using synchronized gas bubble injection. There are two purposes served by discharge initiation in the bubble. Firstly, it creates a favorable condition for electrical breakdown. Secondly, the gas bubble provides an opportunity for the direct spectroscopy of plasma light emission, avoiding water absorption. The effect of water absorption on captured spectra was studied. It was observed that the emission intensity of the Ha line and a shockwave amplitude generated by discharge strongly depend on the size of the gas bubble in the moment of the discharge initiation. It was found that the plasma in the underwater spark channel does not correspond to a source of black-body radiation. This study can be also very useful for understanding the difference between discharges produced directly in a liquid and discharges produced in gas/vapor bubbles surrounded by a liquid.
Diagnostics and Control of Pumping Stations in Water Supply Systems: Hybrid Model for Fault Operating Modes
Authors: Milošević Marko , Radić Milan , Rašić-Amon Milica , Litričin Dragan , Stajić Zoran
Published: July 2022

This paper indicates the importance and advantages of the application of hybrid models in the control of water supply systems. A range of possibilities provided by this scientific approach is presented in the practical examples related to the fault diagnostics and fault-tolerant control in the pumping station (PS) control systems. It is presented that continuous monitoring and recording of the data of the pumping stations operation processes (electrical parameters such as electrical power, pressure or flow in the pipelines, water levels in the tanks, changes in various discrete states, etc.) could represent a significant resource that can be used to develop various hybrid models using the appropriate “data-driven” techniques. During this process, data are transformed into information, and thereafter, information into knowledge. Based on this knowledge, the control of PS operation can be significantly improved and a significant increase in the user’s satisfaction can be achieved while the maintenance and operation costs can be reduced.
The Determinant of Sukuk Rating: Agency Theory and Asymmetry Theory Perspectives
Authors: Santoso Bedjo , Widodo Widodo , Akbar Muhammad Taufiq , Ahmad Khaliq , Setianto Rahmat Heru
Published: July 2022

This research aims to develop a determinant variable of the Sukuk rating derived from agency and asymmetry theories. This research is essential because Sukuk or Islamic Bonds is needed in Indonesia, with 85% of its population out of 320 million people being Muslim. Many studies on the determinants of Sukuk ratings have been conducted and are still trending research. However, they are rarely observed from the perspective of agency and asymmetry theories, which are the basis for the relationship between principals and investors. The relationship produces three primary variables in the Sukuk rating determinants, namely financial disclosure quality (FDQ), accounting-based risks (ABRs), and earnings management (EM). This research used 570 panel annual reports from 2018 to 2020 and involved 190 firm-issued Sukuk. Meanwhile, the variables’ reflection used several indicators. SEM (structural equation modeling) was used for the statistical analysis with the help of PLS—primarily smart PLS version. The results exposed that FDQ, ABRs, and EM derived from the two theories are affected significantly by the determinant of the Sukuk rating. In comparison, earnings management successfully moderates the FDQ and Sukuk rating variables but fails to moderate the ABRs to the Sukuk rating. The conclusion also revealed that these relationship theories are fundamental in developing the Sukuk rating. However, the variables should be more complex for future research. With significant results, the agency and asymmetry theories proxied by three variables can explain the Sukuk rating. Accordingly, these theories are relevant as approaches in determining important factors of the Sukuk rating.
Low Sidelobe Series-Fed Patch Planar Array with AMC Structure to Suppress Parasitic Radiation
Authors: Tan Qingquan , Fan Kuikui , Yang Wenwen , Luo Guoqing
Published: July 2022

For automobile radar systems, the antenna array requires a low sidelobe level (SLL) to reduce interference. A low-SLL and low-cost planar antenna array are proposed in this article for millimeter-wave automotive radar applications. The proposed array consists of six linear series-fed patch arrays, a series distribution network using a grounded co-planar waveguide (GCPW), and a bed of nails. First, a hybrid HFSS-MATLAB optimization platform is set up to easily obtain good impedance matching and low SLL of the linear series-fed patch array. Then, a six-way GCPW power divider is designed to combine the optimized linear sub-array to achieve a planar array. However, since CCPW is a semi-open structure, like a microstrip line, the parasitic radiation generated by the GCPW feeding network will lead to the deterioration of the SLL. To solve this problem, a bed of nails—as an artificial magnetic conductor (AMC)—is designed and placed above the feeding networking to create an electromagnetic stopband in the working band. Its working mechanism has been explained in detail. The feeding network cannot effectively radiate electromagnetic waves into free space. Thus, the parasitic radiation can be suppressed. A low-SLL planar array prototype working at 79 GHz is designed, manufactured, and measured. The measured results confirm that the proposed low-SLL planar array has a −10 dB impedance bandwidth of 3 GHz from 77 to 80 GHz and a maximum peak gain of 21 dBi. The measured SLL is −24 dB and −23 dB in the E-plane and H-plane at 79 GHz, respectively. The proposed low SLL array can be used for adaptive cruise control (ACC) system applications.
A Joint Estimation Method of the Channel Phase Error and Motion Error for Distributed SAR on a Single Airborne Platform Based on a Time-Domain Correlation Method
Authors: Zhang Chi , Li Han , Li Linghao , Liu Shujiang , Ding Zegang
Published: July 2022

Distributed synthetic aperture radar (SAR) is a system in which transmitting or receiving arrays are distributed on multiple platforms or at different locations on one platform. Distributed SAR can be used for high-resolution wide-swath (HRWS) imaging. The typical platform used for distributed SAR is a satellite constellation, which has long baselines and an ideal trajectory. Instead of satellite constellations, this paper focuses on distributed SAR on a single airborne platform, for which the channel error and motion error are coupled. Furthermore, the traditional channel error estimation methods are invalid. Thus, based on the time-domain correlation method (TDCM), this article proposes a joint estimation method of the channel phase error and motion error for the distributed SAR on a single airborne platform. Firstly, a channel error and motion error coupled phase error model of the distributed SAR is constructed. A joint estimation method of the channel phase error and motion error is then proposed. Finally, a simulation and real data processing are provided to demonstrate the effectiveness of the proposed method.
Sensing the Urban Environment by Automotive SAR Imaging: Potentials and Challenges
Authors: Tebaldini Stefano , Manzoni Marco , Tagliaferri Dario , Rizzi Marco , Monti-Guarnieri Andrea Virgilio , Prati Claudio Maria , Spagnolini Umberto , Nicoli Monica , Russo Ivan , Mazzucco Christian
Published: July 2022

In this paper, we discuss the possibility of generating high-resolution mapping of urban (or extra-urban) environments by the application of synthetic aperture radar (SAR) processing concepts to the data collected by mm-wave automotive radars installed on-board commercial vehicles. The study is motivated by the fact that radar sensors are becoming an indispensable component of the equipment of modern vehicles, being characterized by low cost, good performance, and affordable processing; therefore, in the future, nearly every single vehicle could be potentially equipped with radar devices capable of high-resolution imaging, enabled by application of SAR processing methodologies. Throughout this paper, we aim to discuss the role of SAR imaging in the automotive context under a theoretical and experimental perspective. First, we present the resulting benefits in terms of angular resolution and signal-to-noise ratio. Then, we discuss relevant technological aspects, such as suppression of angular ambiguities, fine estimation of platform motion, and SAR processing architectures, and we present a preliminary evaluation of the required computational costs. Finally, we will present a number of experimental results based on open road campaign data acquired using an 8-channel MIMO radar at 77 GHz, considering the cases of side-looking SAR, forward SAR, and SAR imaging of moving targets.
Response of Sediment Connectivity to Altered Convergence Processes Induced by Forest Roads in Mountainous Watershed
Authors: Zhao Qinghe , Jing Yaru , Wang An , Yu Zaihui , Liu Yi , Yu Jinhai , Liu Guoshun , Ding Shengyan
Published: July 2022

Forest roads significantly affect sediment connectivity in mountainous catchments by contributing to the production of and disturbing the confluence of sediment-loaded runoff. This study considered forest roads as pathways and sinks of sediment-loaded runoff to understand the effects of forest roads on the confluence characteristics and sediment connectivity in mountainous a catchment using a scenario simulation. In order to determine the contribution and spatial relationship between sediment connectivity and influencing factors, this study utilized buffer analysis, an extremely randomized tree model, and multiscale geographically weighted regression. The results show that the presence of forest roads significantly changes the transport process and connectivity of runoff and sediment in the mountainous catchment. Specifically, flow length increases, but flow accumulation, upslope contributing area, and topographic index decrease with increasing distance from roads and streams. Meanwhile, the effects of roads on convergence characteristics and sediment connectivity are mainly manifested within a certain threshold that varies with different confluence characteristics. Moreover, sediment connectivity increases when considering roads as pathways and sinks of sediment-loaded runoff, especially on the upper hillslopes intercepted by roads and at the road–stream crossings. In addition, the closer the distance to the roads, the greater the impact of road on the confluence characteristics and sediment connectivity. Change in flow length is the most important factor affecting the sediment connectivity among all of the other convergence, terrain, and spatial distance characteristics. The longer the flow length, the lower the sediment connectivity. In conclusion, this study demonstrates that the altered confluence processes by roads increases the possibility that sediment-loaded runoff will be transported to the catchment outlet, which is of significance for the proper management of forest roads in mountainous catchments.