bluuebunny/crossref_metadata_2025 huggingface dataset:
Multipoint Forming Using Hole-Type Rubber Punch
Authors: Tolipov Abror , Hassanin Hany , El-Sayed Mahmoud Ahmed , Eldessouky Hossam Mohamed , Alsaleh Naser A. , Alfozan Adel Khalid , Essa Khamis , Ahmadein Mahmoud
Published: March 2022

Reconfigurable multipoint forming is a flexible sheet forming technique aimed at customised sheet metal products. However, one drawback of multipoint forming is the cost and time needed to set up and align the upper and lower pin matrices. This study introduces an optimisation study of a novel hole-type rubber punch replacing the top pin matrix of multipoint incremental forming, aiming to reduce pins setting up and alignment complexity and time. Finite element modelling and design of experiments were used to investigate the effect of hole-type rubber punch configuration such as hole size, hole type, and the compression ratio on the wrinkling, thickness variation, and shape deviation. This research shows that the most significant process parameter in all responses was the hole size. The compression ratio of the material was found to be insignificant in wrinkling and shape deviation. The hole-type rubber punch parameters were found to be a hole size of 9 mm, circular hole type, and a compression ratio of 75%. This experimentally resulted in an improved parts wrinkling of 80%, when compared to using solid rubber punch, with the added benefits of reduction of the cost and time needed to set up and align the pin matrices.
The Formation Mechanisms and Evolution of Multi-Phase Inclusions in Ti-Ca Deoxidized Offshore Structural Steel
Authors: Rong Zhe , Liu Hongbo , Zhang Peng , Wang Feng , Wang Geoff , Zhao Baojun , Tang Fengqiu , Ma Xiaodong
Published: March 2022

To understand and clarify the formation mechanisms and evolution of complex inclusions in Ti-Ca deoxidized offshore structural steel, inclusions in industrial steel were systematically investigated. The number density of total inclusions generally decreased from Ladle Furnace (LF), Vacuum Degassing (VD), Tundish to the final product except for Ti and Ca addition. The major inclusions during the refining process were CaO-Al2O3-SiO2-(MgO)-TiOx and CaO-Al2O3-SiO2. CaO-Al2O3-SiO2-(MgO)-TiOx inclusion initially originated from the combination of CaO-SiO2-(MgO) in refining slag or refractory and deoxidization product Al2O3 and TiO2. With the refining process proceeding and Ca addition, the Al2O3 concentration in the CaO-Al2O3-SiO2-(MgO)-TiOx inclusions gradually dropped while the CaO and TiO2 concentrations gradually increased. The CaO-Al2O3-SiO2 inclusions originally came from refining slag, existing as 2CaO∙ Al2O3∙ SiO2, and maintained a liquid state during the early stage of LF. After Ca treatment, it was gradually transferred to 2CaO∙ SiO2 due to Al2O3 continuously being reduced by Ca. The liquidus of 2CaO∙ SiO2 inclusion was higher than that of molten steel, so they presented as a solid-state during the refining process. After welding thermal simulation, CaO-Al2O3-SiO2-(MgO)-TiOx inclusions were proven effective for inducing intragranular acicular ferrite (IAF) while CaO-Al2O3-SiO2 was inert for IAF promotion. Additionally, Al2O3-MgO spinel in multiphase CaO-Al2O3-SiO2-(MgO)-TiOx inclusion has different formation mechanisms: (1) initial formation as individual Al2O3-MgO spinel as a solid-state in molten steel; (2) and it presented as a part of liquid inclusion CaO-Al2O3-SiO2-(MgO)-TiOx and firstly precipitated due to its low solubility.
Effect of Ultrasonic Nanocrystal Surface Modification Treatment at Room and High Temperatures on the High-Frequency Fatigue Behavior of Inconel 718 Fabricated by Laser Metal Deposition
Authors: Karimbaev Ruslan M. , Cho In Sik , Pyun Young Sik , Amanov Auezhan
Published: March 2022

In this work, the effect of ultrasonic nanocrystal surface modification (UNSM) treatment at room and high temperatures (RT and HT) on the high-frequency fatigue behavior of Inconel 718 alloy fabricated by laser metal deposition (LMD) process was experimentally investigated. UNSM treatment at RT and HT modified a surface morphology and produced a nanostructured surface layer with a thickness of approximately 120 and 140 µm, respectively. The surface roughness of the untreated sample was reduced, while the surface hardness was notably increased after the UNSM treatment at RT and HT. Both increased with increasing the UNSM treatment temperature. Fatigue behavior of the untreated samples at various stress levels was slightly improved after the UNSM treatment at RT and HT. This is mainly due to the formation of a fine grained nanostructured surface layer with reduced porosity and highly induced compressive residual stress. Fatigue mechanisms of the samples were comprehensively discussed based on the quantitative SEM fractographic analysis.
Martensitic Transformation and Barocaloric Effect in Co-V-Ga-Fe Paramagnetic Heusler Alloy
Authors: Liu Jie , Li Zhe , Liu Hongwei , Yu Litao , Zhang Yuanlei , Cao Yiming , Xu Kun , Liu Yongsheng
Published: March 2022

In the present study, polycrystalline Co50V34Ga16−xFex (1≤x≤2) quaternary Heusler alloys were fabricated by the arc-melting method. It was found that they undergo a paramagnetic martensitic transformation (MT) from the L21-type cubic austenitic structure to the D022 tetragonal martensitic structure. With the increase of the Fe concentration, the MT shifts towards a higher temperature range, which is strongly related to the variation of the valence electron concentration. Moreover, it was also found that the MT exhibited by every alloy is sensitive to the applied hydrostatic pressure due to a relatively high difference in volume between the two phases. By using the quasi-direct method based on caloric measurements, the barocaloric effect (BCE) associated with the hydrostatic pressure-driven MT was estimated in the studied alloys. The results demonstrated that the sample with x=1.5 performs an optimal BCE among these three alloys.
Evolution of Nanostructured Carbon Coatings Quality via RT-CVD and Their Tribological Behavior on Nodular Cast Iron
Authors: Moreno-Bárcenas Alejandra , Arizpe Zapata Jesus Alejandro , Esneider Alcalá Miguel Ángel , Téllez Ramírez Jaime , Magaña Hernández Antonio , García-García Alejandra
Published: March 2022

One of the most critical problems in industry is the wear of materials. Graphene, as a tribological coating, has shown a tremendous impact on sliding surfaces. In this work, a few layers of graphene were grown on a nodular cast iron substrate, a material used in camshafts. The studied synthesis parameters in a rapid thermal chemical vapor deposition (CVD) furnace and the quality of the final coating are presented. The influence of hydrogen flow and cooling rate was evaluated, obtaining the best results in the few layers of graphene structure and deposition at 10 sccm and 4 °C/min. A standard ball-on-disk tribometer was used to assess the coefficient of friction on a few layers of graphene on nodular cast iron substrates. Laboratory test results show that the few layers of graphene coating resulted in a 60% reduction in coefficient of friction and close to a 70% reduction in volume removed versus the uncoated substrates. The surface of the substrate was not modified before a few layers of graphene growth to have a working surface close to camshafts obtained by the industrial process at ARBOMEX SA de CV.
The Effect of Wall Thickness and Scanning Speed on the Martensitic Transformation and Tensile Properties of Selective Laser Melted NiTi Thin-Wall Structures
Authors: Guo Fangmin , Guo Yanbao , Kong Xiangguang , Xiong Zhiwei , Hao Shijie
Published: March 2022

In this study, we analyzed the coupling effect of laser scanning speed and wall thickness on the phase transformation behavior and tensile properties of selective laser melted NiTi thin-wall structures. It is demonstrated that either scanning speed or wall thickness has their respective influence rule, whereas this influence could be changed when coupling them together; that is, under different scanning speeds, the effect of wall thickness could be different. It is found that the deviation of phase transformation temperature among different wall thicknesses is ~3.7 °C at 400 mm/s, while this deviation increases to ~23.5 °C at 600 mm/s. However, the deviation of phase transformation peak width among different wall thicknesses shows little change under different scanning speeds. At low scanning speed, the samples with thicker wall thickness exhibit better tensile ductility than thinner, whereas they all show poor tensile properties and brittle behavior at high scanning speed. This uncertain influence rule is mainly due to the interaction effect between different thermal histories generated by wall thickness and scanning speed.
Effects of Extrusion and Rolling Processes on the Microstructure and Mechanical Properties of Zn-Li-Ag Alloys
Authors: Lu Yujiao , Liu Ying , Dai Yilong , Yan Yang , Yu Kun
Published: March 2022

In this work, a novel Zn-0.5%Li-0.1%Ag alloy was cast and extruded into rods, which were rolled into a plate, and the effects of extrusion and rolling on the microstructure and mechanical properties of the Zn-0.5%Li-0.1%Ag alloy were evaluated. The results show that grain strengthening occurs in all of the alloys because of the presence of nano-LiZn4 precipitates. The extrusion and rolling processes promote grain size refinement and orientation order, and the microstructure and mechanical properties of the Zn-0.5%Li-0.1%Ag alloy can be significantly improved by secondary processing. The elastic modulus and tensile strength of the processed alloy increased to 83.1 GPa and 251.6 MPa, respectively, compared to 75.6 GPa and 185.8 MPa, respectively, for the as-cast Zn-0.5%Li-0.1%Ag alloy. More importantly, elongation was greatly improved, from 16.9% to 92.6%, which is an increase of up to 448%, and there were transgranular cleavage planes and intergranular cleavage planes in the fracture surfaces. The intergranular cleavage planes were dominant, and they showed ductile fracture characteristics.
High Resolution Magic Angle Spinning Proton NMR Study of Alzheimer’s Disease with Mouse Models
Authors: Füzesi Mark V. , Muti Isabella H. , Berker Yannick , Li Wei , Sun Joseph , Habbel Piet , Nowak Johannes , Xie Zhongcong , Cheng Leo L. , Zhang Yiying
Published: March 2022

Alzheimer’s disease (AD) is a crippling condition that affects millions of elderly adults each year, yet there remains a serious need for improved methods of diagnosis. Metabolomic analysis has been proposed as a potential methodology to better investigate and understand the progression of this disease; however, studies of human brain tissue metabolomics are challenging, due to sample limitations and ethical considerations. Comprehensive comparisons of imaging measurements in animal models to identify similarities and differences between aging- and AD-associated metabolic changes should thus be tested and validated for future human non-invasive studies. In this paper, we present the results of our highresolution magic angle spinning (HRMAS) nuclear magnetic resonance (NMR) studies of AD and wild-type (WT) mouse models, based on animal age, brain regions, including cortex vs. hippocampus, and disease status. Our findings suggest the ability of HRMAS NMR to differentiate between AD and WT mice using brain metabolomics, which potentially can be implemented in in vivo evaluations.
Broadband-NIRS System Identifies Epileptic Focus in a Child with Focal Cortical Dysplasia—A Case Study
Authors: Vezyroglou Aikaterini , Hebden Peter , De Roever Isabel , Thornton Rachel , Mitra Subhabrata , Worley Alan , Alves Mariana , Dean Emma , Cross Judith Helen , Tachtsidis Ilias
Published: March 2022

Epileptic seizures are transiently occurring symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Previous functional near-infrared spectroscopy (fNIRS) studies during seizures have focused in only monitoring the brain oxygenation and haemodynamic changes. However, few tools are available to measure actual cellular metabolism during seizures, especially at the bedside. Here we use an in-house developed multichannel broadband NIRS (or bNIRS) system, that, alongside the changes in oxy-, deoxy- haemoglobin concentration (HbO2, HHb), also quantifies the changes in oxidised cytochrome-c-oxidase Δ(oxCCO), a marker of cellular oxygen metabolism, simultaneously over 16 different brain locations. We used bNIRS to measure metabolic activity alongside brain tissue haemodynamics/oxygenation during 17 epileptic seizures at the bedside of a 3-year-old girl with seizures due to an extensive malformation of cortical development in the left posterior quadrant. Simultaneously Video-EEG data was recorded from 12 channels. Whilst we did observe the expected increase in brain tissue oxygenation (HbD) during seizures, it was almost diminished in the area of the focal cortical dysplasia. Furthermore, in the area of seizure origination (epileptic focus) ΔoxCCO decreased significantly at the time of seizure generalization when compared to the mean change in all other channels. We hypothesize that this indicates an incapacity to sustain and increase brain tissue metabolism during seizures in the region of the epileptic focus.
Bone Fragility in Chronic Kidney Disease Stage 3 to 5: The Use of Vitamin D Supplementation
Authors: Ureña Torres Pablo Antonio , Souberbielle Jean Claude , Solal Martine Cohen
Published: March 2022

Frequently silent until advanced stages, bone fragility associated with chronic kidney disease-mineral and bone disease (CKD-MBD) is one of the most devastating complications of CKD. Its pathophysiology includes the reduction of active vitamin D metabolites, phosphate accumulation, decreased intestinal calcium absorption, renal alpha klotho production, and elevated fibroblast growth factor 23 (FGF23) levels. Altogether, these factors contribute firstly to secondary hyperparathyroidism, and ultimately, to micro- and macrostructural bone changes, which lead to low bone mineral density and an increased risk of fracture. A vitamin D deficiency is common in CKD patients, and low circulating 25(OH)D levels are invariably associated with high serum parathyroid hormone (PTH) levels as well as with bone mineralization defects, such as osteomalacia in case of severe forms. It is also associated with a variety of non-skeletal diseases, including cardiovascular disease, diabetes mellitus, multiple sclerosis, cancer, and reduced immunological response. Current international guidelines recommend supplementing CKD patients with nutritional vitamin D as in the general population; however, there is no randomized clinical trial (RCT) evaluating the effect of vitamin D (or vitamin D+calcium) supplementation on the risk of fracture in the setting of CKD. It is also unknown what level of circulating 25(OH)D would be sufficient to prevent bone abnormalities and fractures in these patients. The impact of vitamin D supplementation on other surrogate endpoints, including bone mineral density and bone-related circulating biomarkers (PTH, FGF23, bone-specific alkaline phosphatase, sclerostin) has been evaluated in several RTCs; however, the results were not always translated into an improvement in long-term outcomes, such as reduced fracture risk. This review provides a brief and comprehensive update on CKD-related bone fragility and the use of natural vitamin D supplementation in these patients.
Acoustics-Actuated Microrobots
Authors: Xiao Yaxuan , Zhang Jinhua , Fang Bin , Zhao Xiong , Hao Nanjing
Published: March 2022

Microrobots can operate in tiny areas that traditional bulk robots cannot reach. The combination of acoustic actuation with microrobots extensively expands the application areas of microrobots due to their desirable miniaturization, flexibility, and biocompatibility features. Herein, an overview of the research and development of acoustics-actuated microrobots is provided. We first introduce the currently established manufacturing methods (3D printing and photolithography). Then, according to their different working principles, we divide acoustics-actuated microrobots into three categories including bubble propulsion, sharp-edge propulsion, and in-situ microrotor. Next, we summarize their established applications from targeted drug delivery to microfluidics operation to microsurgery. Finally, we illustrate current challenges and future perspectives to guide research in this field. This work not only gives a comprehensive overview of the latest technology of acoustics-actuated microrobots, but also provides an in-depth understanding of acoustic actuation for inspiring the next generation of advanced robotic devices.
Systematic Review of Plasmid AmpC Type Resistances in Escherichia coli and Klebsiella pneumoniae and Preliminary Proposal of a Simplified Screening Method for ampC
Authors: Rodríguez-Guerrero Enrique , Callejas-Rodelas Juan Carlos , Navarro-Marí José María , Gutiérrez-Fernández José
Published: March 2022

Beta-lactamase (BL) production is a major public health problem. Although not the most frequent AmpC type, AmpC-BL is increasingly isolated, especially plasmid AmpC-BL (pAmpC-BL). The objective of this study was to review information published to date on pAmpC-BL in Escherichia coli and Klebsiella pneumoniae, and on the epidemiology and detection methods used by clinical microbiology laboratories, by performing a systematic review using the MEDLINE PubMed database. The predictive capacity of a screening method to detect AmpC-BL using disks with cloxacillin (CLX) was also evaluated by studying 102 Enterobacteriaceae clinical isolates grown in CHROMID ESBL medium with the addition of cefepime (FEP), cefoxitin (FOX), ertapenem (ETP), CLX, and oxacillin with CLX. The review, which included 149 publications, suggests that certain risk factors (prolonged hospitalization and previous use of cephalosporins) are associated with infections by pAmpC-BL-producing microorganisms. The worldwide prevalence has increased over the past 10 years, with a positivity rate ranging between 0.1 and 40%, although AmpC was only detected when sought in a targeted manner. CMY-2 type has been the most prevalent pAmpC-BL-producing microorganism. The most frequently used phenotypic method has been the double-disk synergy test (using CLX disks or phenyl-boronic acid and cefotaxime [CTX] and ceftazidime) and the disk method combined with these inhibitors. In regard to screening methods, a 1-µg oxacillin disk with CLX showed 88.9% sensitivity, 100% specificity, 100% positive predictive value (PPV), 98.9% negative predictive value (NPV), and 98.9% validity index (VI). This predictive capacity is reduced with the addition of extended-spectrum beta-lactamases, showing 62.5% sensitivity, 100% specificity, 100% PPV, 93.5% NPV, and 94.1% VI. In conclusion, there has been a worldwide increase in the number of isolates with pAmpC-BL, especially in Asia, with CMY-2 being the most frequently detected pAmpC-BL-producing type of microorganism. Reduction in its spread requires routine screening with a combination of phenotypic methods (with AmpC inhibitors) and genotypic methods (multiplex PCR). In conclusion, the proposed screening technique is an easy-to-apply and inexpensive test for the detection of AmpC-producing isolates in the routine screening of multidrug-resistant microorganisms.
Pharyngeal Colonization by Kingella kingae, Transmission, and Pathogenesis of Invasive Infections: A Narrative Review
Authors: Yagupsky Pablo
Published: March 2022

With the appreciation of Kingella kingae as a prime etiology of osteoarticular infections in young children, there is an increasing interest in the pathogenesis of these diseases. The medical literature on K. kingae’s colonization and carriage was thoroughly reviewed. Kingella kingae colonizes the oropharynx after the second life semester, and its prevalence reaches 10% between the ages of 12 and 24 months, declining thereafter as children reach immunological maturity. Kingella kingae colonization is characterized by the periodic substitution of carried organisms by new strains. Whereas some strains frequently colonize asymptomatic children but are rarely isolated from diseased individuals, others are responsible for most invasive infections worldwide, indicating enhanced virulence. The colonized oropharyngeal mucosa is the source of child-to-child transmission, and daycare attendance is associated with a high carriage rate and increased risk of invasive disease. Kingella kingae elaborates a potent repeat-in-toxin (RTXA) that lyses epithelial, phagocytic, and synovial cells. This toxin breaches the epithelial barrier, facilitating bloodstream invasion and survival and the colonization of deep body tissues. Kingella kingae colonization and carriage play a crucial role in the person-to-person transmission of the bacterium, its dissemination in the community, and the pathogenesis of invasive infections.
Unraveling the Tropaeolum majus L. (Nasturtium) Root-Associated Bacterial Community in Search of Potential Biofertilizers
Authors: Dal’Rio Isabella , Mateus Jackeline Rossetti , Seldin Lucy
Published: March 2022

Although Tropaeolum majus (nasturtium) is an agriculturally and economically important plant, especially due to the presence of edible flowers and its medicinal properties, its microbiome is quite unexplored. Here, the structure of the total bacterial community associated with the rhizosphere, endosphere and bulk soil of T. majus was determined by 16S rRNA amplicon metagenomic sequencing. A decrease in diversity and richness from bulk soil to the rhizosphere and from the rhizosphere to the endosphere was observed in the alpha diversity analyses. The phylum Proteobacteria was the most dominant in the bacteriome of the three sites evaluated, whereas the genera Pseudomonas and Ralstonia showed a significantly higher relative abundance in the rhizosphere and endosphere communities, respectively. Plant growth-promoting bacteria (236 PGPB) were also isolated from the T. majus endosphere, and 76 strains belonging to 11 different genera, mostly Serratia, Raoultella and Klebsiella, showed positive results for at least four out of six plant growth-promoting tests performed. The selection of PGPB associated with T. majus can result in the development of a biofertilizer with activity against phytopathogens and capable of favoring the development of this important plant.
Microbial Community Structure and Ecological Networks during Simulation of Diatom Sinking
Authors: Liu Ying , Zeng Mengchu , Xie Zhe , Ning Daliang , Zhou Jizhong , Yu Xi , Liu Rulong , Zhang Li , Fang Jiasong
Published: March 2022

Microbial-mediated utilization of particulate organic matter (POM) during its downward transport from the surface to the deep ocean constitutes a critical component of the global ocean carbon cycle. However, it remains unclear as to how high hydrostatic pressure (HHP) and low temperature (LT) with the sinking particles affects community structure and network interactions of the particle-attached microorganisms (PAM) and those free-living microorganisms (FLM) in the surrounding water. In this study, we investigated microbial succession and network interactions in experiments simulating POM sinking in the ocean. Diatom-derived 13C- and 12C-labeled POM were used to incubate surface water microbial communities from the East China Sea (ECS) under pressure (temperature) of 0.1 (25 °C), 20 (4 °C), and 40 (4 °C) MPa (megapascal). Our results show that the diversity and species richness of the PAM and FLM communities decreased significantly with HHP and LT. Microbial community analysis indicated an increase in the relative abundance of Bacteroidetes at high pressure (40 MPa), mostly at the expense of Gammaproteobacteria, Alphaproteobacteria, and Gracilibacteria at atmospheric pressure. Hydrostatic pressure and temperature affected lifestyle preferences between particle-attached (PA) and free-living (FL) microbes. Ecological network analysis showed that HHP and LT enhanced microbial network interactions and resulted in higher vulnerability to networks of the PAM communities and more resilience of those of the FLM communities. Most interestingly, the PAM communities occupied most of the module hubs of the networks, whereas the FLM communities mainly served as connectors of the modules, suggesting their different ecological roles of the two groups of microbes. These results provided novel insights into how HHP and LT affected microbial community dynamics, ecological networks during POM sinking, and the implications for carbon cycling in the ocean.
Comparison of Fermentation Behaviors and Characteristics of Tomato Sour Soup between Natural Fermentation and Dominant Bacteria-Enhanced Fermentation
Authors: Li Juan , Wang Xiaoyu , Wu Wenyan , Jiang Jingzhu , Feng Dandan , Shi Yuanyuan , Hu Ping
Published: March 2022

In this study, the correlations between microbial communities with physicochemical properties and volatile flavor compounds (VFCs) during the fermentation of traditional tomato sour soup (CTN) are explored. The results of high-throughput sequencing (HTS) of CTN showed that Lacticaseibacillus (28.67%), Enterobacter (12.37%), and Providencia (12.19%) were the dominant bacteria in the first round of fermentation, while Lacticaseibacillus (50.11%), Enterobacter (13.86%), and Providencia (8.61%) were the dominant bacteria in the second round of fermentation. Additionally, the dominant fungi genera of the first fermentation were Pichia (65.89%) and Geotrichum (30.56%), and the dominant fungi genera of the second fermentation were Pichia (73.68%), Geotrichum (13.99%), and Brettanomyces (5.15%). These results indicate that Lacticaseibacillus is one of the main dominant bacteria in CTN. Then, the dominant strain Lacticaseibacillus casei H1 isolated from CTN was used as a culture to ferment tomato sour soup to monitor dynamic changes in the physicochemical properties and VFCs during enhanced fermentation of tomato sour soup (TN). The physicochemical analysis showed that, compared with CTN, the TN group not only produced acid faster but also had an earlier peak of nitrite and a lower height. The results of the GC–IMS analysis showed that the ester and alcohol contents in the TN group were 1.26 times and 1.8 times that of the CTN group, respectively. Using an O2PLS-DA analysis, 11 bacterial genera and 18 fungal genera were identified as the functional core flora of the CTN group flavor production, further verifying the importance of dominant bacteria for the production of VFCs. This study proved that enhanced fermentation not only shortens the fermentation cycle of tomato sour soup, but also significantly improves its flavor quality, which has great value in the industrial production of tomato sour soup and in the development of a vegetable fermentation starter.
Characterization of Uropathogenic Escherichia coli Reveals Hybrid Isolates of Uropathogenic and Diarrheagenic (UPEC/DEC) E. coli
Authors: Tanabe Rodrigo H. S. , Dias Regiane C. B. , Orsi Henrique , de Lira Daiany R. P. , Vieira Melissa A. , dos Santos Luís F. , Ferreira Adriano M. , Rall Vera L. M. , Mondelli Alessandro L. , Gomes Tânia A. T. , Camargo Carlos H. , Hernandes Rodrigo T.
Published: March 2022

(1) Background: Pathogenic Escherichia coli are divided into two groups: diarrheagenic (DEC) and extraintestinal pathogenic (ExPEC) E. coli. ExPEC causing urinary tract infections (UTIs) are termed uropathogenic E. coli (UPEC) and are the most common cause of UTIs worldwide. (2) Methods: Here, we characterized 112 UPEC in terms of phylogroup, serotype, the presence of virulence factor-encoding genes, and antimicrobial resistance. (3) Results: The majority of the isolates were assigned into the phylogroup B2 (41.07%), and the serogroups O6 (12.5%) and O25 (8.9%) were the most frequent. Five hybrid UPEC (4.5%), with markers from two DEC pathotypes, i.e., atypical enteropathogenic (aEPEC) and enteroaggregative (EAEC) E. coli, were identified, and designated UPEC/aEPEC (one isolate) and UPEC/EAEC (four isolates), respectively. Three UPEC/EAEC harbored genes from the pap operon, and the UPEC/aEPEC carried ibeA. The highest resistance rates were observed for ampicillin (46.4%) and trimethoprim/sulfamethoxazole (34.8%), while 99.1% of the isolates were susceptible to nitrofurantoin and/or fosfomycin. Moreover, 9.8% of the isolates were identified as Extended Spectrum β-Lactamase producers, including one hybrid UPEC/EAEC. (4) Conclusion: Our data reinforce that hybrid UPEC/DEC are circulating in the city of Botucatu, Brazil, as uropathogens. However, how and whether these combinations of genes influence their pathogenicity is a question that remains to be elucidated.
Harnessing Paenarthrobacter ureafaciens YL1 and Pseudomonas koreensis YL2 Interactions to Improve Degradation of Sulfamethoxazole
Authors: Yu Lan , Wang Yingning , Shan Xiaoqing , Ma Fang , Guo Haijuan
Published: March 2022

Sulfamethoxazole (SMX) is a widespread and persistent pollutant in the environment. Although the screening and analysis of SMX-degrading bacteria have been documented, the interaction mechanisms of functional microorganisms are still poorly understood. This study constructed a consortium with strain YL1 and YL2 supplied with SMX as the sole carbon and energy source. The coexisting mechanism and the removal of SMX of the consortium were investigated. The total oxidizable carbon (TOC) removal rate of the combined bacterial system was 38.94% compared to 29.45% for the single bacterial system at the same biomass. The mixed bacterial consortium was able to resist SMX at concentrations up to 400 mg/L and maintained a stable microbial structure at different culture conditions. The optimum conditions found for SMX degradation were 30 °C, pH 7.0, a shaking speed of 160 r·min−1, and an initial SMX concentration of 200 mg·L−1. The degradation of SMX was accelerated by the addition of YL2 for its ability to metabolize the key intermediate, 4-aminophenol. The removal rate of 4-aminophenol by strain YL2 reached 19.54% after 5 days. Genome analysis revealed that adding riboflavin and enhancing the reducing capacity might contribute to the degradation of SMX. These results indicated that it is important for the bioremediation of antibiotic-contaminated aquatic systems to understand the metabolism of bacterial communities.
The Proteogenome of Symbiotic Frankia alni in Alnus glutinosa Nodules
Authors: Pujic Petar , Alloisio Nicole , Miotello Guylaine , Armengaud Jean , Abrouk Danis , Fournier Pascale , Normand Philippe
Published: March 2022

Omics are the most promising approaches to investigate microbes for which no genetic tools exist such as the nitrogen-fixing symbiotic Frankia. A proteogenomic analysis of symbiotic Frankia alni was done by comparing those proteins more and less abundant in Alnus glutinosa nodules relative to N-replete pure cultures with propionate as the carbon source and ammonium as the nitrogen-source. There were 250 proteins that were significantly overabundant in nodules at a fold change (FC) ≥ 2 threshold, and 1429 with the same characteristics in in vitro nitrogen-replete pure culture. Nitrogenase, SuF (Fe–Su biogenesis) and hopanoid lipids synthesis determinants were the most overabundant proteins in symbiosis. Nitrogenase was found to constitute 3% of all Frankia proteins in nodules. Sod (superoxide dismutase) was overabundant, indicating a continued oxidative stress, while Kats (catalase) were not. Several transporters were overabundant including one for dicarboxylates and one for branched amino acids. The present results confirm the centrality of nitrogenase in the actinorhizal symbiosis.
The Gut Microbiota Influenced by the Intake of Probiotics and Functional Foods with Prebiotics Can Sustain Wellness and Alleviate Certain Ailments like Gut-Inflammation and Colon-Cancer
Authors: Dahiya Divakar , Nigam Poonam Singh
Published: March 2022

The gut microbiota is composed of several microbial strains, with diverse and variable combinations in healthy and sick persons, changing at different stages of life. A healthy balance between host and gut microorganisms must be maintained in order to perform the normal physiological, metabolic, and immune functions and prevent disease development. Disturbances in the balance of the gut microbiota by diverse reasons initiate several health issues and promote the progression of certain diseases. This review is based on published research and reports that describe the role of probiotic microorganisms in the sustainability of health and the alleviation of certain diseases. Information is presented on the GRAS strains that are used as probiotics in the food industry for the production of fermented milk, yogurt, fermented food, functional foods, and probiotic drinks. To maintain a healthy microbiota, probiotic supplements in the form of freeze-dried live cells of probiotic strains are also available in different forms to consumers. The health benefits of lactic acid bacteria and other microorganisms and their role in the control of certain diseases such as gut inflammation, diabetes, and bowel cancer and in the safeguarding of the gut epithelial permeability from the invasion of pathogens are discussed.
The Effects of Surface Lignite Mines Closure on the Particulates Concentrations in the Vicinity of Large-Scale Extraction Activities
Authors: Pavloudakis Francis , Sachanidis Chariton , Roumpos Christos
Published: March 2022

The European green deal and energy transition policies and the competition primarily shaped by the high price of carbon dioxide emission allowances and the consistently reduced cost of renewable energy technologies directly affect the coal and lignite extraction industry. Lignite production in Western Macedonia Lignite Centre reduced from 43.2 million tons in 2010 to 10.3 million tons in 2020. This development affects the ambient air quality of the large lignite mine area, as evidenced by the records of 10 monitoring stations incorporating the laser light scattering method. All stations measure reduced particulate matter (PM10 and PM2.5) concentrations compared to the period before 2010, while the number of annual exceedances of the limit value for the daily average PM10 concentrations has been decreased. Moreover, differences in air quality measurements of monitoring stations related to their distance from mining activities now tend to be minimized. Based on these facts, it can be predicted that, after the closure of lignite extraction and the electricity generation activities, the concentration of particulates in the atmosphere will reach the typical levels for rural areas of Southern Europe, no matter what the mines’ land reforestation and repurposing program will include.
Colours of Gemmy Phosphates from the Gavà Neolithic Mines (Catalonia, Spain): Origin and Archaeological Significance
Authors: Díaz-Acha Yael , Campeny Marc , Casas Lluís , Di Febo Roberta , Ibañez-Insa Jordi , Jawhari Tariq , Bosch Josep , Borrell Ferran , Jorge-Villar Susana Esther , Greneche Jean-Marc , Tauler Esperança , Melgarejo Joan Carles
Published: March 2022

In the Neolithic Gavà mines, variscite and turquoise were exploited for ornaments manufacturing, although some prospective pits and tunnels were dug on other similar greenish minerals such as smectite or kandite. A 3D study of the distribution of mineral phases allows us to determine the parameters involved in variscite colours. Methods are comprised of quantitative colourimetry, thin section petrography, SEM-BSE-EDS, EMPA, XRD, Raman spectroscopy, and 57Fe Mössbauer spectrometry. Mapping of the mines indicates that colour is not directly dependent on depth. Although variscite from Gavà is poor in Cr3+ and V+3 compared with gemmy variscite from other localities, the deep green samples content has the highest values of Cr3+. In the case of cryptocrystalline mixtures with jarosite, phosphosiderite, or goethite, variscite tends to acquire a greenish brown to olivaceous hue. If white minerals such as quartz, kandite, crandallite, or alunite are involved in the mixtures, variscite and turquoise colours become paler.
Geochemical Study of the Iron Age Settlement Occupational Layer and the Early Roman Time Agricultural Layer at Voorthuizen, The Netherlands
Authors: Druzhinina Olga , Gedminienė Laura , van den Berghe Kasper
Published: March 2022

The application of geochemical analysis in archaeology provides a better understanding of ancient human activities. This paper presents the results of geochemical multi-element, LOI, MS, and geochronological analyses of a cultural layer at the Voorthuizen (The Netherlands) archaeological site. The study has revealed a difference in the geochemical composition of an occupational surface in the Iron Age settlement and an early Roman Time agricultural horizon. The former is enriched in Ba, Sr, Rb, Th, Cl, and Mg, while the latter displays elevated P, Pb, Ni, Mn, and V values. The study has provided a deeper insight into the agricultural techniques applied at the Voorthuizen site and on the so-called Celtic Fields, known as ancient field systems dating from the same period and widespread throughout north-west Europe. It seems that household waste was not used as a fertilizer at Voorthuizen, while the application of manure is characteristic of Celtic Fields. However, phosphorous values in the Voorthuizen agricultural horizon are comparable to those in the Celtic Fields, suggesting similar sources of P in both cases. Elevated Si and “mobile” Fe, Mn, V, Pb, As, and Sn, along with higher MS measurements, are indicative of the use of extra mineral matter for the fertilization of the Voorthuizen ancient arable field.
Optimization of Parameters for Rheological Properties and Strength of Cemented Paste Backfill Blended with Coarse Aggregates
Authors: Wang Jiandong , Wu Aixiang , Ruan Zhuen , Bürger Raimund , Wang Yiming , Wang Shaoyong , Zhang Pingfa , Gao Zhaoquan
Published: March 2022

Cemented paste backfill (CPB) technology is widely used for environmental protection and underground goaf treatment. The influences of solid concentration, coarse aggregates dosage, and cement dosage on the rheological properties and compressive strength of CPB blended with coarse aggregates (CA-CPB) are investigated through three-factor and four-level orthogonal experiments. The dynamic shear stress and plastic viscosity are selected to characterize the rheological properties of CA-CPB. The uniaxial compressive strength (UCS) is used to describe the compressive strength. The effect of each factor on rheological properties is different from that on UCS. The most significant influences on rheological properties and UCS are solid concentration and cement dosage, respectively. The optimal levels of each factor for rheological properties and UCS are different, resulting in different optimal combinations obtained through range analysis. Therefore, the overall desirability function approach is employed to perform multiple response optimization. The optimal parameters for high fluidity and strength obtained provide valuable information for the CA-CPB process in the Chifeng Baiyinnuoer Lead and Zinc Mine.
Study of Synthetic Titania Slags Demonstrating Characteristics Similar to High Titania Ilmenite Slag
Authors: Gupta Avishek Kumar , Aula Matti , Sreenivasan Harisankar , Mäkelä Pasi , Huttula Marko , Fabritius Timo
Published: March 2022

The upgradation of the ilmenite ore, using a pyrometallurgy method, is performed using a carbothermic reduction of the ilmenite. A high titania slag is obtained which is used as a feedstock for the TiO2 pigment production. The slag is cooled after tapping in big molds and can take ten days to cool. This cooling method has remained the same since the inception of ilmenite smelting and recently rapid cooling through granulation has been utilized. The work presented in this paper focuses on the microstructural study of the slags that were prepared using different techniques and cooled at different cooling rates. Various analytical techniques, such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectroscopy (ICP-OES), and X-ray photoelectron spectroscopy (XPS) were used to exhibit the similarity of these synthetic slags to the properties of high titania ilmenite slag. The slag consisted mostly of pseudo-brookite phase with a M3O5 stoichiometry and smaller amounts of silicate and rutile phase. A glassy phase of silica was observed and most of the impurities were found to be present in the silicate phase. These silica phases were observed to be separate from the pseudo-brookite phase and along the phase boundaries. Micro-cracking of the slag surface, which is the characteristic of the M3O5 phase formed in the ilmenite slag, were observed under the SEM analysis. The XPS analysis revealed that faster cooling does result in lower amount of oxidation but the difference in the TiO2 and Ti2O3 composition can have larger impact on oxidation than the cooling speed.
A Numerical Simulation of Electrical Resistivity of Fiber-Reinforced Composites, Part 1: Brittle Cementitious Concrete
Authors: Miri Alireza , Ehsani Rojina , Tehrani Fariborz M.
Published: March 2022

The durability of concrete has a significant influence on the sustainability and resilience of various infrastructures, including buildings, bridges, roadways, dams, and other applications. Penetration of corrosive agents intensified by exposure to freeze-thaw cycles and the presence of early-age cracks is a common cause of reinforced concrete degradation. Electrical resistivity is a vital physical property of cementitious composites to assess the remained service life of reinforced concrete members subjected to corrosive ions attacks. The application of steel fibers reduces the vulnerability of concrete by limiting crack propagation, but complicates field and laboratory testing due to the random distribution of conductive fibers within the body of the concrete. Numerical simulations facilitate proper modeling of such random distribution to improve the reliability of testing measures. Hence, this paper investigates the influence of fiber reinforcement characteristics on electrical resistivity using multi-physics finite element models. Results examine modeling challenges and include insights on the sensitivity of resistivity measures to fiber reinforcement. Concluding remarks provide expected bias of electrical resistivity in the presence of steel fibers and endeavor to facilitate the development of practical guidelines for assessing the durability of fiber-reinforced concrete members using standard electrical resistivity testing procedures.
A Comprehensive Computational Investigation into the Conserved Virulent Proteins of Shigella species Unveils Potential Small-Interfering RNA Candidates as a New Therapeutic Strategy against Shigellosis
Authors: Palit Parag , Chowdhury Farhana Tasnim , Baruah Namrata , Sarkar Bonoshree , Mou Sadia Noor , Kamal Mehnaz , Siddiqua Towfida Jahan , Noor Zannatun , Ahmed Tahmeed
Published: March 2022

Shigella species account for the second-leading cause of deaths due to diarrheal diseases among children of less than 5 years of age. The emergence of multi-drug-resistant Shigella isolates and the lack of availability of Shigella vaccines have led to the pertinence in the efforts made for the development of new therapeutic strategies against shigellosis. Consequently, designing small-interfering RNA (siRNA) candidates against such infectious agents represents a novel approach to propose new therapeutic candidates to curb the rampant rise of anti-microbial resistance in such pathogens. In this study, we analyzed 264 conserved sequences from 15 different conserved virulence genes of Shigella sp., through extensive rational validation using a plethora of first-generation and second-generation computational algorithms for siRNA designing. Fifty-eight siRNA candidates were obtained by using the first-generation algorithms, out of which only 38 siRNA candidates complied with the second-generation rules of siRNA designing. Further computational validation showed that 16 siRNA candidates were found to have a substantial functional efficiency, out of which 11 siRNA candidates were found to be non-immunogenic. Finally, three siRNA candidates exhibited a sterically feasible three-dimensional structure as exhibited by parameters of nucleic acid geometry such as: the probability of wrong sugar puckers, bad backbone confirmations, bad bonds, and bad angles being within the accepted threshold for stable tertiary structure. Although the findings of our study require further wet-lab validation and optimization for therapeutic use in the treatment of shigellosis, the computationally validated siRNA candidates are expected to suppress the expression of the virulence genes, namely: IpgD (siRNA 9) and OspB (siRNA 15 and siRNA 17) and thus act as a prospective tool in the RNA interference (RNAi) pathway. However, the findings of our study require further wet-lab validation and optimization for regular therapeutic use for treatment of shigellosis.
Curcumin–Induced Stabilization of Protein–Based Nano-Delivery Vehicles Reduces Disruption of Zwitterionic Giant Unilamellar Vesicles
Authors: Okagu Ogadimma D. , Abioye Raliat O. , Udenigwe Chibuike C.
Published: March 2022

Curcumin-loaded native and succinylated pea protein nanoparticles, as well as zwitterionic giant unilamellar vesicles were used in this study as model bioactive compound loaded-nanoparticles and biomembranes, respectively, to assess bio-nano interactions. Curcumin-loaded native protein-chitosan and succinylated protein-chitosan complexes, as well as native protein-chitosan and succinylated protein-chitosan hollow, induced leakage of the calcein encapsulated in the giant unilamellar vesicles. The leakage was more pronounced with hollow protein-chitosan complexes. However, curcumin-loaded native protein and curcumin-loaded succinylated protein nanoparticles induced calcein fluorescence quenching. Dynamic light scattering measurements showed that the interaction of curcumin-loaded native protein, curcumin-loaded succinylated protein, native protein-chitosan, and succinylated protein-chitosan complexes with the giant unilamellar vesicles caused a major reduction in the size of the lipid vesicles. Confocal and widefield fluorescence microscopy showed rupturing of the unilamellar vesicles after treatment with native pea protein-chitosan and succinylated pea protein-chitosan complexes. The nature of interaction between the curcumin-loaded protein nanoparticles and the biomembranes, at the bio-nano interface, is influenced by the encapsulated curcumin. Findings from this study showed that, as the protein plays a crucial role in stabilizing the bioactive compound from chemical and photodegradation, the encapsulated nutraceutical stabilizes the protein nanoparticle to reduce its interaction with biomembranes.
Interaction of the Fungal Metabolite Harzianic Acid with Rare-Earth Cations (La3+, Nd3+, Sm3+, Gd3+)
Authors: De Tommaso Gaetano , Salvatore Maria Michela , Siciliano Antonietta , Staropoli Alessia , Vinale Francesco , Nicoletti Rosario , DellaGreca Marina , Guida Marco , Salvatore Francesco , Iuliano Mauro , Andolfi Anna
Published: March 2022

Rare-earth elements are emerging contaminants of soil and water bodies which destiny in the environment and effects on organisms is modulated by their interactions with natural ligands produced by bacteria, fungi and plants. Within this framework, coordination by harzianic acid (H2L), a Trichoderma secondary metabolite, of a selection of tripositive rare-earth cations Ln3+ (Ln3+ = La3+, Nd3+, Sm3+, and Gd3+) was investigated at 25 °C, and in a CH3OH/0.1 M NaClO4 (50/50 w/w) solvent, using mass spectrometry, circular dichroism, UV–Vis spectrophotometry, and pH measurements. Experimental data can be satisfactorily explained by assuming, for all investigated cations, the formation of a mono-complex (LnL+) and a bis-complex (LnL2−). Differences were found between the formation constants of complexes of different Ln3+ cations, which can be correlated with ionic radius. Since gadolinium is the element that raises the most concern among lanthanide elements, its effects on organisms at different levels of biological organization were explored, in the presence and absence of harzianic acid. Results of ecotoxicological tests suggest that harzianic acid can decrease gadolinium biotoxicity, presumably because of complex formation with Gd3+.