bluuebunny/crossref_metadata_2025 huggingface dataset:
Recovery of Rare Earth Oxides from Flotation Concentrates of Bastnaesite Ore by Ultra-Fine Centrifugal Concentration
Authors: Norgren Alex , Anderson Corby
Published: September 2021

Historically, the ability to effectively separate carbonate gangue from bastnaesite via flotation has frequently proven to be challenging without sacrificing significant rare earth oxide (REO) grade or recovery. However, in light of the fact that the rare earth bearing minerals often exhibit higher specific gravities than the carbonate gangue, the possibility exists that the use of gravity separation could be used to achieve such a selective separation. This however is complicated by the fact that, in cases such as this study when the liberation size is finer than 50 microns, most traditional gravity separation methods become increasingly challenging. The aim of this study is to determine the applicability of centrifugal concentrators to beneficiate ultra-fine (UF) bastnaesite and calcite bearing flotation concentrates. By using a UF Falcon, it was possible to achieve initial gravity REO recoveries exceeding 90% while rejecting on the order of 25% to 35% of the total calcium from an assortment of rougher and cleaner flotation concentrates. Additionally, when additional stages of cleaner UF Falcon gravity separation were operated in an open circuit configuration, it was possible, from an original fine feed of 35 microns containing 50.5% REO and 5.5% Ca, to upgrade up to approximately 59% REO and 2.0% calcium. While not the goal of this study, these results also support previous limited data to suggest that UF Falcons are potentially capable of treating a wider range of materials than they were originally designed for, including feeds rich in heavy mineral content.
Three-Phase Six-Level Multilevel Voltage Source Inverter: Modeling and Experimental Validation
Authors: Meraj Sheikh Tanzim , Yahaya Nor Zaihar , Hasan Kamrul , Hossain Lipu Molla Shahadat , Masaoud Ammar , Ali Sawal Hamid Md , Hussain Aini , Othman Muhammad Murtadha , Mumtaz Farhan
Published: September 2021

This research proposes a three-phase six-level multilevel inverter depending on twelve-switch three-phase Bridge and multilevel DC-link. The proposed architecture increases the number of voltage levels with less power components than conventional inverters such as the flying capacitor, cascaded H-bridge, diode-clamped and other recently established multilevel inverter topologies. The multilevel DC-link circuit is constructed by connecting three distinct DC voltage supplies, such as single DC supply, half-bridge and full-bridge cells. The purpose of both full-bridge and half-bridge cells is to provide a variable DC voltage with a common voltage step to the three-phase bridge’s mid-point. A vector modulation technique is also employed to achieve the desired output voltage waveforms. The proposed inverter can operate as a six-level or two-level inverter, depending on the magnitude of the modulation indexes. To guarantee the feasibility of the proposed configuration, the proposed inverter’s prototype is developed, and the experimental results are provided. The proposed inverter showed good performance with high efficiency of 97.59% following the IEEE 1547 standard. The current harmonics of the proposed inverter was also minimized to only 5.8%.
Population-Based Distribution of Mycobacterium avium and Mycobacterium intracellulare in Japan
Authors: Morimoto Kozo , Ato Manabu , Hasegawa Naoki , Mitarai Satoshi
Published: September 2021

This study aimed to clarify the population-based distributions of Mycobacterium avium and Mycobacterium intracellulare in Japan. We conducted a combined analysis of the national insurance claim and microbiological databases. The incidence rates of M. avium by province were similar throughout the country, with some exceptions, such as in Okinawa, probably because the bathing customs are different from those in mainland Japan. In contrast, M. intracellulare showed a gradual increase from the central part of the country to the southwestern region, with precise gradation, which may indicate infection sources in the natural environment. This study found that assessment of the infection route of M. intracellulare in the natural environment, which is similar to the distribution of M. intracellular patients, is warranted. In conclusion, improvement of the household environment could decrease the incidence of M. avium, while environmental countermeasures will be required to decrease the incidence of M. intracellulare.
A Selection of Platforms to Evaluate Surface Adhesion and Biofilm Formation in Controlled Hydrodynamic Conditions
Authors: Gomes Luciana C. , Mergulhão Filipe J. M.
Published: September 2021

The early colonization of surfaces and subsequent biofilm development have severe impacts in environmental, industrial, and biomedical settings since they entail high costs and health risks. To develop more effective biofilm control strategies, there is a need to obtain laboratory biofilms that resemble those found in natural or man-made settings. Since microbial adhesion and biofilm formation are strongly affected by hydrodynamics, the knowledge of flow characteristics in different marine, food processing, and medical device locations is essential. Once the hydrodynamic conditions are known, platforms for cell adhesion and biofilm formation should be selected and operated, in order to obtain reproducible biofilms that mimic those found in target scenarios. This review focuses on the most widely used platforms that enable the study of initial microbial adhesion and biofilm formation under controlled hydrodynamic conditions—modified Robbins devices, flow chambers, rotating biofilm devices, microplates, and microfluidic devices—and where numerical simulations have been used to define relevant flow characteristics, namely the shear stress and shear rate.
Re-Emergence and Spread of Haemorrhagic Septicaemia in Germany: The Wolf as a Vector?
Authors: Kutzer Peter , Szentiks Claudia A. , Bock Sabine , Fritsch Guido , Magyar Tibor , Schulze Christoph , Semmler Torsten , Ewers Christa
Published: September 2021

Since 2010, outbreaks of haemorrhagic septicaemia (HS) caused by Pasteurella (P.) multocida capsular type B (PmB) emerged in Germany. In 2017, we noticed a close spatiotemporal relationship between HS outbreak sites and wolf (Canis lupus) territories. Thus, the main objectives of our study were to investigate the molecular epidemiology of German PmB-HS-isolates and to assess the role of wolves as putative vectors of this pathogen. We collected 83 PmB isolates from HS outbreaks that occurred between 2010 and 2019 and sampled 150 wolves, which were found dead in the years 2017 to 2019, revealing another three PmB isolates. A maximum-likelihood-based phylogeny of the core genomes of 65 PmB-HS-isolates and the three PmB-wolf-isolates showed high relatedness. Furthermore, all belonged to capsular:LPS:MLST genotype B:L2:ST122RIRDC and showed highly similar virulence gene profiles, but clustered separately from 35 global ST122RIRDC strains. Our data revealed that German HS outbreaks were caused by a distinct genomic lineage of PmB-ST122 strains, hinting towards an independent, ongoing epidemiologic event. We demonstrated for the first time, that carnivores, i.e., wolves, might harbour PmB as a part of their oropharyngeal microbiota. Furthermore, the results of our study imply that wolves can carry the pathogen over long distances, indicating a major role of that animal species in the ongoing epidemiological event of HS in Germany.
Preclinical Development of a Bacteriophage Cocktail for Treating Multidrug Resistant Pseudomonas aeruginosa Infections
Authors: Camens Sophie , Liu Sha , Hon Karen , Bouras George , Psaltis Alkis , Wormald Peter-John , Vreugde Sarah
Published: September 2021

A Pseudomonas aeruginosa (P. aeruginosa) airway infection is one of the predominant causes contributing to the high morbidity and mortality rates in cystic fibrosis (CF) patients. The emergence of antibiotic resistant P. aeruginosa strains has led to an urgent need for new therapeutic approaches. Bacteriophages (phages) are viruses that can infect and lyse specific bacteria, providing a potential alternative approach in targeting antibiotic-resistant strains. We aim to isolate and characterise novel P. aeruginosa phages for combination in a cocktail to kill P. aeruginosa. One particular phage, PA4, could lyse 14/20 clinical isolates as observed through spot assays. This phage could significantly reduce the growth of bacteria in vitro, as determined through planktonic adsorption and inhibition assays as well as crystal violet- and LIVE/DEAD-stained biofilm assays. A morphological and genomic analysis revealed that PA4 belongs to the Myoviridae family and contained 66,450 bp. The broad infectivity profile, good stability in various pH and temperature conditions, lytic ability and the absence of the absences of antibiotic resistance, toxic and lysogenic genes suggest that PA4 is a good candidate for clinical grade use. Overall, phage therapy represents a promising alternative treatment option to antibiotics when treating a P. aeruginosa infection.
Incorporation of Geometallurgical Input into Gold Mining System Simulation to Control Cyanide Consumption
Authors: Órdenes Javier , Wilson Ryan , Peña-Graf Felipe , Navarra Alessandro
Published: September 2021

The Alhué deposit (Melipilla, Chile) is an example of a hydrothermal Au-Ag-Zn(-Pb) vein system hosted within the volcanic rocks of the Las Chilcas Formation. The dominant ore minerals observed are free electrum and native gold associated with silver sulfosalts, and with magnetite and base metal sulphides, including pyrite +/− sphalerite-galena-chalcopyrite. The alteration assemblage in the veins mainly consists of quartz epidote-chlorite-actinolite with lesser smectite, amphibole, and calcite-kaolinite-garnet. Mineralized veins also contain variable amounts of base metals, some of which (e.g., copper and iron) are considered harmful to the extraction of precious metals. Iron and especially copper minerals are known cyanide consumers; ore type classification schemes that do not consider the detrimental effects of such mineralogy or process elements can ultimately result in metal losses from ore feed restrictions, as well as spikes in cyanide consumption and higher operating costs. Mineralogical and geological variation can nonetheless be managed by applying alternating modes of operation as demonstrated in this paper; the decision to switch between modes is governed by current and forecasted stockpile levels feeding into the process. Simulations based on experiences at the Alhué deposit are provided that demonstrate the importance of standardized operational modes and their potential impact on cyanide consumption control.
A Simple Synthesis Route for Selectively Methylated β-Cyclodextrin Using a Copper Complex Sandwich Protecting Strategy
Authors: Bucur Stefan , Niculaua Marius , Ciobanu Catalina Ionica , Lungu Neculai Catalin , Mangalagiu Ionel
Published: September 2021

This communication reports a novel synthesis route for the preparation of monofunctionalized β-cyclodextrin in a single stage. The approach involves only the in-situ protection of secondary hydroxyl groups as an excellent alternative to the classical procedure involving a series of five steps of protection and deprotection of hydroxyl groups (both primary and secondary ones) belonging to β-cyclodextrin.
Dissipation and Distribution of Picarbutrazox Residue Following Spraying with an Unmanned Aerial Vehicle on Chinese Cabbage (Brassica campestris var. pekinensis)
Authors: Kim Chang Jo , Jeong Won Tae , Kyung Kee Sung , Lee Hee-Dong , Kim Danbi , Song Ho Sung , Kang Younkoo , Noh Hyun Ho
Published: September 2021

We assessed the residual distribution and temporal trend of picarbutrazox sprayed by agricultural multicopters on Chinese cabbage and considered fortification levels and flying speeds. In plot 2, 14 days after the last spraying, the residues decreased by ~91.3% compared with those in the samples on day 0. The residues in the crops decreased by ~40.8% of the initial concentration owing to growth (dilution effect) and by ~50.6% after excluding the dilution effect. As the flight speed increased, picarbutrazox residues decreased (p < 0.05, least significant deviation [LSD]). At 2 m s−1 flight speed, the residual distribution differed from the dilution rate of the spraying solution. The average range of picarbutrazox residues at all sampling points was 0.007 to 0.486, below the limit of quantitation −0.395, 0.005–0.316, and 0.005–0.289 mg kg−1 in plots 1, 2, 3, and 4, respectively, showing significant differences (p < 0.05, LSD). These results indicated that the residual distribution of picarbutrazox sprayed by using a multicopter on the Chinese cabbages was not uniform. However, the residues were less than the maximum residue limit in all plots. Accordingly, picarbutrazox was considered to have a low risk to human health if it was sprayed on cabbage according to the recommended spraying conditions.
Design, Synthesis, Antibacterial, and Antitumor Activity of Linear Polyisocyanide Quaternary Ammonium Salts with Different Structures and Chain Lengths
Authors: Zhang Hongguang , Liu Lijia , Hou Peng , Liu Jun , Fu Shuang
Published: September 2021

The development of organic polymer materials for disinfection and sterilization is thought of as one of the most promising avenues to solve the growth and spread of harmful microorganisms. Here, a series of linear polyisocyanide quaternary ammonium salts (L-PQASs) with different structures and chain lengths were designed and synthesized by polymerization of phenyl isocyanide monomer containing a 4-chloro-1-butyl side chain followed by quaternary amination salinization. The resultant compounds were characterized by 1H NMR and FT-IR. The antibacterial activity of L-PQASs with different structures and chain lengths against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was evaluated by determining the minimum inhibitory concentrations (MICs). The L-POcQAS-M50 has the strongest antimicrobial activity with MICs of 27 μg/mL against E. coli and 32 μg/mL against S. aureus. When the L-PQASs had the same polymerization degree, the order of the antibacterial activity of the L-PQASs was L-POcQAS-Mn > L-PBuQAS-Mn > L-PBnQAS-Mn > L-PDBQAS-Mn (linear, polyisocyanide quaternary ammonium salt, monomer, n = 50,100). However, when L-PQASs had the same side chain, the antibacterial activity reduced with the increase of the molecular weight of the main chain. These results demonstrated that the antibacterial activity of L-PQASs was dependent on the structure of the main chain and the length of the side chain. In addition, we also found that the L-POcQAS-M50 had a significant killing effect on MK-28 gastric cancer cells.
Volatile Composition and Biological Activity of Jordanian Commercial Samples of R. coriaria L. Fruits
Authors: Naik Rajashri R. , Shakya Ashok K. , Ferri Benedetta , Oriquat Ghaleb A. , Pistelli Luisa , Numan Nawfal A. M.
Published: September 2021

The present paper reports the GC-HS-SPME analysis of volatile emission and GC-MS analysis of chemical composition of essential oil of R. coriaria fruits of eight different samples of R. coriaria L. fruits (“sumac” folk name), collected from Jordanian agricultural field and the local market. The analyses show an important variability among the Sumac samples probably due to the origin, cultivation, harvesting period, drying, and conservation of the plant material. The main class of component present in all samples was monoterpenes (43.1 to 72.9%), except for one sample which evidenced a high percentage of sesquiterpene hydrocarbons (38.5%). The oxygenated monoterpenes provided a contribution to total class of monoterpenes ranging from 10.1 to 24.3%. A few samples were rich in monoterpene hydrocarbons. Regarding the single components present in all the volatile emissions, β-caryophyllene was the main compound in most of the analyzed samples, varying from 34.6% to 7.9%. Only two samples were characterized by α-pinene as the main constituent (42.2 and 40.8% respectively). Essential oils were collected using hydro-distillation method. Furfural was the main constituent in almost all the analyzed EOs (4.9 to 48.1%), except in one of them, where β-caryophyllene was the most abundant one. β-caryophyllene ranged from 1.2 to 10.6%. Oxygenated monoterpenes like carvone and carvacrol ranged from 3.2–9.1% and 1.0–7.7% respectively. Cembrene was present in good amount in EO samples EO-2 to EO-8. The antioxidant capacities of the fruit essential oils from R. coriaria were assessed using spectrophotometry to measure free radical scavenger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and inhibition of β-carotene bleaching (BCB). The essential oils from the fruits of the different samples of R. coriaria exhibited the MIC value ranging from 32.8 to 131.25 µg/mL against S. aureus ATCC 6538 and 131.25 to 262.5 µg/mL against E. coli ATCC 8739. The MIC values of ciprofloxacin were 0.59 and 2.34 µg/mL against S. aureus ATCC 6538 and E. coli ATCC 8739, respectively.
A Novel LC–MS/MS-Based Method for the Diagnosis of ADA2 Deficiency from Dried Plasma Spot
Authors: Cafaro Alessia , Pigliasco Federica , Barco Sebastiano , Penco Federica , Schena Francesca , Caorsi Roberta , Volpi Stefano , Tripodi Gino , Gattorno Marco , Cangemi Giuliana
Published: September 2021

Adenosine Deaminase 2 Deficiency (DADA2) (OMIM: 607575) is a monogenic, autoinflammatory disease caused by the loss of functional homozygous or heterozygous mutations in the ADA 2 gene (previously CECR1, Cat Eye Syndrome Chromosome Region 1). A timely diagnosis is crucial to start Anti-TNF therapies that are efficacious in controlling the disease. The confirmation of DADA2 is based on DNA sequencing and enzymatic assay. It is, thus, very important to have robust and reliable assays that can be rapidly utilized in specialized laboratories that can centralize samples from other centers. In this paper, we show a novel enzymatic assay based on liquid chromatography-tandem mass spectrometry that allows the accurate determination of the ADA2 enzyme activity starting from very small amounts of plasma spotted on filter paper (dried plasma spot). The method allows significantly distinguishing healthy controls from affected patients and carriers and could be of help in implementing the diagnostic workflow of DADA2.
Structural Investigations on the SH3b Domains of Clostridium perfringens Autolysin through NMR Spectroscopy and Structure Simulation Enlighten the Cell Wall Binding Function
Authors: Shan Yubao , He Xiaoling , Wang Zi , Yue Xiali , Zhu Jiang , Yang Yunhuang , Liu Maili
Published: September 2021

Clostridium perfringens autolysin (CpAcp) is a peptidoglycan hydrolase associated with cell separation, division, and growth. It consists of a signal peptide, ten SH3b domains, and a catalytic domain. The structure and function mechanisms of the ten SH3bs related to cell wall peptidoglycan binding remain unclear. Here, the structures of CpAcp SH3bs were studied through NMR spectroscopy and structural simulation. The NMR structure of SH3b6 was determined at first, which adopts a typical β-barrel fold and has three potential ligand-binding pockets. The largest pocket containing eight conserved residues was suggested to bind with peptide ligand in a novel model. The structures of the other nine SH3bs were subsequently predicted to have a fold similar to SH3b6. Their ligand pockets are largely similar to those of SH3b6, although with varied size and morphology, except that SH3b1/2 display a third pocket markedly different from those in other SH3bs. Thus, it was supposed that SH3b3-10 possess similar ligand-binding ability, while SH3b1/2 have a different specificity and additional binding site for ligand. As an entirety, ten SH3bs confer a capacity for alternatively binding to various peptidoglycan sites in the cell wall. This study presents an initial insight into the structure and potential function of CpAcp SH3bs.
Defect Structures of Magnetic Nanoparticles in Smectic A Liquid Crystals
Authors: Novotná Vladimíra , Lejček Lubor , Hamplová Věra , Vejpravová Jana
Published: September 2021

Topological defects in anisotropic fluids like liquid crystals serve as a playground for the research of various effects. In this study, we concentrated on a hybrid system of chiral rod-like molecules doped by magnetic nanoparticles. In textures of the smectic A phase, we observed linear defects and found that clusters of nanoparticles promote nucleation of smectic layer defects just at the phase transition from the isotropic to the smectic A (SmA) phase. In different geometries, we studied and analysed creation of defects which can be explained by attractive elastic forces between nanoparticles in the SmA phase. On cooling the studied hybrid system, clusters grow up to the critical dimension, and the smectic texture is stabilised. The presented effects are theoretically described and explained if we consider the elastic interaction of two point defects and stabilisation of prismatic dislocation loops due to the presence of nanoparticles.
Polyphenols from Citrus Tacle® Extract Endowed with HMGCR Inhibitory Activity: An Antihypercholesterolemia Natural Remedy
Authors: Grande Fedora , Occhiuzzi Maria Antonietta , Perri Maria Rosaria , Ioele Giuseppina , Rizzuti Bruno , Statti Giancarlo , Garofalo Antonio
Published: September 2021

Tacle® is a citrus fruit obtained from the crossbreeding of Clementine and Tarocco cultivars. This fruit retains a promising nutraceutical potential most likely due to a high content in polyphenols, among which the main constituents are the two glycosides naringin and hesperidin. Herein, we evaluated, through an in vitro assay, the capability of Tacle extracts to inhibit the hydroxymethylglutaryl-CoA reductase enzyme, which plays a key role in cholesterol biosynthesis. The results obtained spurred us to investigate whether the anti-enzymatic activity observed may be due to a direct interaction of aglycones naringenin and hesperetin with the enzyme catalytic site. Molecular docking simulations indicated that these two compounds are able to anchor to the protein with binding modes and affinities similar to those found for statins, which represent mainstream medications against hypercholesterolemia. The overall results showed an interesting nutraceutical potential of Tacle, suggesting that its extract could be used for dietary supplementation in the treatment of moderate hypercholesterolemia.
Phase Behavior and Composition Distribution of Multiphase Hydrocarbon Binary Mixtures in Heterogeneous Nanopores: A Molecular Dynamics Simulation Study
Authors: de Andrade Deraldo de Carvalho Jacobina , Nojabaei Bahareh
Published: September 2021

In this study, molecular dynamics (MD) simulation is used to investigate the phase behavior and composition distribution of an ethane/heptane binary mixture in heterogeneous oil-wet graphite nanopores with pore size distribution. The pore network system consists of two different setups of connected bulk and a 5-nm pore in the middle; and the bulk connected to 5-nm and 2-nm pores. Our results show that nanopore confinement influences the phase equilibrium of the multicomponent hydrocarbon mixtures and this effect is stronger for smaller pores. We recognized multiple adsorbed layers of hydrocarbon molecules near the pore surface. However, for smaller pores, adsorption is dominant so that, for the 2-nm pore, most of the hydrocarbon molecules are in the adsorbed phase. The MD simulation results revealed that the overall composition of the hydrocarbon mixture is a function of pore size. This has major implications for macro-scale unconventional reservoir simulation, as it suggests that heterogenous shale nanopores would host fluids with different compositions depending on the pore size. The results of this paper suggest that modifications should be made to the calculation of overall composition of reservoir fluids in shale nanopores, as using only one overall composition for the entire heterogenous reservoir can result in significant error in recovery estimations.
Fabrication and Application of Zeolite/Acanthophora Spicifera Nanoporous Composite for Adsorption of Congo Red Dye from Wastewater
Authors: Hamd Ahmed , Dryaz Asmaa Ragab , Shaban Mohamed , AlMohamadi Hamad , Abu Al-Ola Khulood A. , Soliman Nofal Khamis , Ahmed Sayed A.
Published: September 2021

Systematic investigations involving laboratory, analytical, and field trials were carried out to obtain the most efficient adsorbent for the removal of congo red (CR) dye from industrial effluent. Modification of the zeolite (Z) by the Acanthophora Spicifera algae (AS; marine algae) was evaluated in terms of adsorption capability of the zeolite to remove CR dye from aqueous solution. The zeolite/algae composite (ZAS) was fabricated using the wet impregnation technique. The AS, Z, and the synthesized ZAS composite were analyzed utilizing various characterization techniques. The newly synthesized ZAS composite has an adsorption capacity that is significantly higher than that of Z and AS, particularly at low CR concentrations. Batch experiments were carried out to explore the effects of different experimental factors, as well as the dye adsorption isotherms and kinetics. Owing to the presence of intermolecular interactions, the computational analysis showed that the adsorption of the CR molecule on zeolite surfaces is exothermic, energetically favorable, and spontaneous. Furthermore, growing the zeolite surface area has no discernible effect on the adsorption energies in all configurations. The ZAS composite may be used as a low-cost substitute adsorbent for the removal of anionic dyes from industrial wastewater at lower dye concentrations, according to the experimental results. Adsorption of CR dye onto Z, AS, and ZAS adsorbents was adequately explained by pseudo-second-order kinetics and the Langmuir isotherm. The sorption mechanism was also evaluated using Weber’s intra-particle diffusion module. Finally, field testing revealed that the newly synthesized adsorbent was 98.0% efficient at extracting dyes from industrial wastewater, proving the foundation of modern eco-friendly materials that aid in the reuse of industrial wastewater.
Aptasensor for the Detection of Mycobacterium tuberculosis in Sputum Utilising CFP10-ESAT6 Protein as a Selective Biomarker
Authors: Azmi Umi Zulaikha Mohd , Yusof Nor Azah , Abdullah Jaafar , Mohammad Faruq , Ahmad Shahrul Ainliah Alang , Suraiya Siti , Raston Nurul Hanun Ahmad , Faudzi Fatin Nabilah Mohd , Khiste Sachin K. , Al-Lohedan Hamad A.
Published: September 2021

A portable electrochemical aptamer-antibody based sandwich biosensor has been designed and successfully developed using an aptamer bioreceptor immobilized onto a screen-printed electrode surface for Mycobacterium tuberculosis (M. tuberculosis) detection in clinical sputum samples. In the sensing strategy, a CFP10-ESAT6 binding aptamer was immobilized onto a graphene/polyaniline (GP/PANI)-modified gold working electrode by covalent binding via glutaraldehyde linkage. Upon interaction with the CFP10-ESAT6 antigen target, the aptamer will capture the target where the nano-labelled Fe3O4/Au MNPs conjugated antibody is used to complete the sandwich format and enhance the signal produced from the aptamer–antigen interaction. Using this strategy, the detection of CFP10-ESAT6 antigen was conducted in the concentration range of 5 to 500 ng/mL. From the analysis, the detection limit was found to be 1.5 ng/mL, thereby demonstrating the efficiency of the aptamer as a bioreceptor. The specificity study was carried out using bovine serum albumin (BSA), MPT64, and human serum, and the result demonstrated good specificity that is 7% higher than the antibody–antigen interaction reported in a previous study. The fabricated aptasensor for M. tuberculosis analysis shows good reproducibility with an relative standard deviation (RSD) of 2.5%. Further analysis of M. tuberculosis in sputum samples have shown good correlation with the culture method with 100% specificity and sensitivity, thus making the aptasensor a promising candidate for M. tuberculosis detection considering its high specificity and sensitivity with clinical samples.
Current Knowledge of Silver and Gold Nanoparticles in Laboratory Research—Application, Toxicity, Cellular Uptake
Authors: Talarska Patrycja , Boruczkowski Maciej , Żurawski Jakub
Published: September 2021

Silver and gold nanoparticles can be found in a range of household products related to almost every area of life, including patches, bandages, paints, sportswear, personal care products, food storage equipment, cosmetics, disinfectants, etc. Their confirmed ability to enter the organism through respiratory and digestive systems, skin, and crossing the blood–brain barrier raises questions of their potential effect on cell function. Therefore, this manuscript aimed to summarize recent reports concerning the influence of variables such as size, shape, concentration, type of coating, or incubation time, on effects of gold and silver nanoparticles on cultured cell lines. Due to the increasingly common use of AgNP and AuNP in multiple branches of the industry, further studies on the effects of nanoparticles on different types of cells and the general natural environment are needed to enable their long-term use. However, some environmentally friendly solutions to chemically synthesized nanoparticles are also investigated, such as plant-based synthesis methods.
3D Printed Multi-Functional Scaffolds Based on Poly(ε-Caprolactone) and Hydroxyapatite Composites
Authors: Liu Fan , Kang Honglei , Liu Zhiwei , Jin Siyang , Yan Guoping , Sun Yunlong , Li Feng , Zhan Haifei , Gu Yuantong
Published: September 2021

3D Printed biodegradable polymeric scaffolds are critical to repair a bone defect, which can provide the individual porous and network microenvironments for cell attachment and bone tissue regeneration. Biodegradable PCL/HA composites were prepared with the blending of poly(ε-caprolactone) (PCL) and hydroxyapatite nanoparticles (HA). Subsequently, the PCL/HA scaffolds were produced by the melting deposition-forming method using PCL/HA composites as the raw materials in this work. Through a serial of in vitro assessments, it was found that the PCL/HA composites possessed good biodegradability, low cell cytotoxicity, and good biocompatibility, which can improve the cell proliferation of osteoblast cells MC3T3-E1. Meanwhile, in vivo experiments were carried out for the rats with skull defects and rabbits with bone defects. It was observed that the PCL/HA scaffolds allowed the adhesion and penetration of bone cells, which enabled the growth of bone cells and bone tissue regeneration. With a composite design to load an anticancer drug (doxorubicin, DOX) and achieve sustained drug release performance, the multifunctional 3D printed PCL/HA/DOX scaffolds can enhance bone repair and be expected to inhibit probably the tumor cells after malignant bone tumor resection. Therefore, this work signifies that PCL/HA composites can be used as the potential biodegradable scaffolds for bone repairing.
Assessing the Biocompatibility of Multi-Anchored Glycoconjugate Functionalized Iron Oxide Nanoparticles in a Normal Human Colon Cell Line CCD-18Co
Authors: Raval Yash S. , Samstag Anna , Taylor Cedric , Huang Guohui , Mefford Olin Thompson , Tzeng Tzuen-Rong Jeremy
Published: September 2021

We have previously demonstrated that iron oxide nanoparticles with dopamine-anchored heterobifunctional polyethylene oxide (PEO) polymer, namely PEO-IONPs, and bio-functionalized with sialic-acid specific glycoconjugate moiety (Neu5Ac(α2-3)Gal(β1-4)-Glcβ-sp), namely GM3-IONPs, can be effectively used as antibacterial agents against target Escherichia coli. In this study, we evaluated the biocompatibility of PEO-IONPs and GM3-IONPs in a normal human colon cell line CCD-18Co via measuring cell proliferation, membrane integrity, and intracellular adenosine triphosphate (ATP), glutathione GSH, dihydrorhodamine (DHR) 123, and caspase 3/7 levels. PEO-IONPs caused a significant decrease in cell viability at concentrations above 100 μg/mL whereas GM3-IONPs did not cause a significant decrease in cell viability even at the highest dose of 500 μg/mL. The ATP synthase activity of CCD-18Co was significantly diminished in the presence of PEO-IONPs but not GM3-IONPs. PEO-IONPs also compromised the membrane integrity of CCD-18Co. In contrast, cells exposed to GM3-IONPs showed significantly different cell morphology, but with no apparent membrane damage. The interaction of PEO-IONPs or GM3-IONPs with CCD-18Co resulted in a substantial decrease in the intracellular GSH levels in a time- and concentration-dependent manner. Conversely, levels of DHR-123 increased with IONP concentrations. Levels of caspase 3/7 proteins were found to be significantly elevated in cells exposed to PEO-IONPs. Based on the results, we assume GM3-IONPs to be biocompatible with CCD-18Co and could be further evaluated for selective killing of pathogens in vivo.
Gastroprotective Effect of Enteral Nutrition Formula in Mice Injected Subcutaneously with Indomethacin
Authors: Yamagishi Yoshiaki , Saiki Rei , Yoshimi Takeshi , Kudo Toshiyuki , Ito Kiyomi
Published: September 2021

We have previously shown that two enteral nutrition formulas suppressed gastric lesions induced by the oral administration of indomethacin (IND) in mice. However, the mechanism of their protective effect is unknown. In this study, the effect of the two enteral nutrition formulas on gastric lesions induced by subcutaneous IND injection was investigated, with the objective of exploring the possibility that they may interact directly with IND in the gastrointestinal tract. Ten-week-old, male, ICR mice were fasted, then orally given either purified water, Mermed® One, or 2-fold diluted Terumeal® 2.0α as enteral nutrition formula (25 mL/kg). IND was injected subcutaneously at 20 mg/kg after 30 min, and the stomach was removed 6 h later and fixed in formalin. The number and area of lesions in the stomachs of mice given enteral nutrition formula was reduced to 56–89% and 34–61%, respectively, compared with the mice given purified water. The time courses of plasma IND concentrations were comparable among the three groups. These results suggested that the effect of these enteral nutrition formulas on gastric lesions did not originate from their direct interaction with IND in the gastrointestinal tract or their effect on the disposition of IND.
Evaluation of the Ridaquick Rotavirus/Adenovirus Immuno-Chromatographic Assay in Real-Life Situation
Authors: Simo-Fouda Francis , Ninove Laetitia , Luciani Léa , Zandotti Christine , Gazin Céline , Charrel Remi N. , Nougairède Antoine
Published: September 2021

Immunochromatographic tests (ICT) are diagnostics tools providing rapid results without the need for specialized equipment. Our aim was to evaluate retrospectively the rotavirus and adenovirus ICT routinely used in the virology laboratory serving the University Hospital of Marseille, France. From January 2017 to March 2020, 715 stool specimens from patients were screened using the Ridaquick Rotavirus/Adenovirus Combi ICT (RR/AC ICT) and a commercially available multiplex PCR detection kit. Rotavirus was detected in 9.2% of specimens by PCR and 7.7% of specimens by RR/AC ICT while adenovirus was detected in 8.5% of specimens by PCR and 2.4% of specimens by RR/AC ICT. The RR/AC ICT parameters for rotavirus were 75.8% sensitivity, 99.2% specificity, 90.9% positive predictive value (PPV) and 97.6% negative predictive value (NPV). The RR/AC ICT parameters for adenovirus were 6.6% sensitivity, 98.0% specificity, 23.5% PPV and 91.8% NPV. While the ICT test may be suitable for rotavirus detection, a PCR–based assay is better adapted for adenovirus detection in stools.
Cytauxzoon sp. and Hepatozoon spp. in Domestic Cats: A Preliminary Study in North-Eastern Italy
Authors: Grillini Marika , Simonato Giulia , Tessarin Cinzia , Dotto Giorgia , Traversa Donato , Cassini Rudi , Marchiori Erica , Frangipane di Regalbono Antonio
Published: September 2021

Knowledge on the presence of Cytauxzoon sp. and Hepatozoon spp. in Italy is scant and mostly limited to a few areas of Northern and Southern regions, respectively. The present study updated the current epidemiological scenario by investigating the occurrence of these protozoa in domestic cats from three broad regions of North-Eastern Italy. Blood samples from cats at risk of vector-borne diseases were processed by PCR to detect Cytauxzoon and Hepatozoon DNA. Blood smears were observed for haemoparasite inclusions. The influence of cat individual data (e.g., provenance, management, indoor/outdoor lifestyle) on the prevalence of haemoprotozoan infections was statistically evaluated. Among 158 cats, Cytauxzoon and Hepatozoon DNA were detected in 6 (3.8%) and 26 (16.5%) animals, respectively. No Hepatozoon gamonts were detected in blood smears, whereas all Cytauxzoon PCR-positive samples were microscopically positive, though with low levels of parasitaemia. Two species of Hepatozoon were identified, Hepatozoon felis (n = 10) and Hepatozoon silvestris (n = 16). Hepatozoon silvestris prevalence values were significantly (p < 0.05) higher in the region Friuli Venezia Giulia and in stray cats. Cytauxzoon sp. was detected in 6/39 (15.4%) stray cats from Friuli Venezia Giulia (Trieste province). These data add new information on the occurrence of these neglected protozoa in domestic cats’ populations.
The Acari Hypothesis, II: Interspecies Operability of Pattern Recognition Receptors
Authors: Retzinger Andrew , Retzinger Gregory
Published: September 2021

Hypersensitivity to galactose-α-1,3-galactose (α-gal) is an informative example of a pathologic IgE-mediated process. By way of their saliva, ticks are able to sensitize humans to tick dietary elements that express α-gal. Mites, which along with ticks constitute the phyletic subclass Acari, feed on proteinaceous foodstuffs that represent most, if not all, human allergens. Given: (1) the gross nature of the pathophysiological reactions of allergy, especially anaphylaxis, (2) the allergenicity of acarian foodstuffs, and (3) the relatedness of ticks and mites, it has been hypothesized that human-acarian interactions are cardinal to the pathogenesis of allergy. In this report, a means by which such interactions contribute to that pathogenesis is proposed.
Prevalence of Vector-Borne Pathogens in Reproductive and Non-Reproductive Tissue Samples from Free-Roaming Domestic Cats in the South Atlantic USA
Authors: Manvell Charlotte , Ferris Kelli , Maggi Ricardo , Breitschwerdt Edward B. , Lashnits Erin
Published: September 2021

Reservoir to multiple species of zoonotic pathogens, free-roaming cats (FRCs) interact with domestic and wild animals, vectors, and humans. To assess the potential for feline vector-borne pathogens to be vertically transmitted, this study surveyed ear tip and reproductive tissues of FRCs from two locations in the South Atlantic United States for Anaplasma, Bartonella, Ehrlichia, hemotropic Mycoplasma, and Rickettsia species. We collected ovary (n = 72), uterus (n = 54), testicle (n = 74), and ear tip (n = 73) tissue from 73 cats, and fetal (n = 20) and placental (n = 19) tissue from 11 queens. Pathogen DNA was amplified utilizing qPCR, confirmed by sequencing. Cats were more frequently Bartonella henselae positive on reproductive tissues (19%, 14/73) than ear tip (5%, 4/73; p = 0.02). B. henselae was amplified from fetus (20%, 4/20) and placenta samples (11%, 2/19). Bartonella spp. infection was more common in cats from North Carolina (76%, 26/34) than Virginia (13%, 5/39; p < 0.0001). Fourteen percent (10/73) of both ear tip and reproductive tissues were positive for hemotropic Mycoplasma spp. Anaplasma, Ehrlichia, and Rickettsia spp. DNA was not amplified from any cat/tissue. These findings suggest that B. henselae preferentially infected cats’ reproductive tissue and reinforces the importance of investigating the potential for B. henselae vertical transmission or induction of reproductive failure.
Inhibition of Scavenger Receptor Class B Type 1 (SR-B1) Expression and Activity as a Potential Novel Target to Disrupt Cholesterol Availability in Castration-Resistant Prostate Cancer
Authors: Pandey Mitali , Cuddihy Grace , Gordon Jacob A. , Cox Michael E. , Wasan Kishor M.
Published: September 2021

There have been several studies that have linked elevated scavenger receptor class b type 1 (SR-B1) expression and activity to the development and progression of castration-resistant prostate cancer (CRPC). SR-B1 facilitates the influx of cholesterol to the cell from lipoproteins in systemic circulation. This influx of cholesterol may be important for many cellular functions, including the synthesis of androgens. Castration-resistant prostate cancer tumors can synthesize androgens de novo to supplement the loss of exogenous sources often induced by androgen deprivation therapy. Silencing of SR-B1 may impact the ability of prostate cancer cells, particularly those of the castration-resistant state, to maintain the intracellular supply of androgens by removing a supply of cholesterol. SR-B1 expression is elevated in CRPC models and has been linked to poor survival of patients. The overarching belief has been that cholesterol modulation, through either synthesis or uptake inhibition, will impact essential signaling processes, impeding the proliferation of prostate cancer. The reduction in cellular cholesterol availability can impede prostate cancer proliferation through both decreased steroid synthesis and steroid-independent mechanisms, providing a potential therapeutic target for the treatment of prostate cancer. In this article, we discuss and highlight the work on SR-B1 as a potential novel drug target for CRPC management.
Self-Fulfilling Prophecies
Authors: Rennick Stephanie
Published: September 2021

Causal loops are a recurring feature in the philosophy of time travel, where it is generally agreed that they are logically possible but may come with a theoretical cost. This paper introduces an unfamiliar set of causal loop cases involving knowledge or beliefs about the future: self-fulfilling prophecy loops (SFP loops). I show how and when such loops arise and consider their relationship to more familiar causal loops.
Optical Detection of VOC Vapors Using Nb2O5 Bragg Stack in Transmission Mode
Authors: Georgiev Rosen , Chorbadzhiyska Yoana , Pavlov Venelin , Georgieva Biliana , Babeva Tsvetanka
Published: September 2021

In this study, an emphasis is put on vapor-sensitive Bragg stacks as an important class of optical sensors. All-niobia Bragg stacks were deposited by spin-coating of sol-gel Nb2O5 thin films alternated with mesoporous layers after proper design through optimization of operating wavelength and number of layers in the stack. Mesoporous Nb2O5 films with different morphology and identical structure were obtained using organic templates (Pluronics PE6200 and PE6800) and subsequent annealing. Transmittance measurements were performed as a detection method that offers technological simplicity and accuracy. It was demonstrated that stacks including PE6200 templated films exhibit higher sensitivity than stacks templated with PE6800. It was assumed and verified by computer-aided modelling of experimental data that mesoporous films prepared with addition of PE6200, although less porous, were more stable compared to those templated with PE6800, and did not collapse during the thermal treatment of the stacks. Furthermore, the reproducibility of optical response was studied by sorption and desorption cycles of acetone vapors. The suitability of all-niobia Bragg stacks for optical sensing of VOCs was discussed.
SP-ILC: Concurrent Single-Pixel Imaging, Object Location, and Classification by Deep Learning
Authors: Yang Zhe , Bai Yu-Ming , Sun Li-Da , Huang Ke-Xin , Liu Jun , Ruan Dong , Li Jun-Lin
Published: September 2021

We propose a concurrent single-pixel imaging, object location, and classification scheme based on deep learning (SP-ILC). We used multitask learning, developed a new loss function, and created a dataset suitable for this project. The dataset consists of scenes that contain different numbers of possibly overlapping objects of various sizes. The results we obtained show that SP-ILC runs concurrent processes to locate objects in a scene with a high degree of precision in order to produce high quality single-pixel images of the objects, and to accurately classify objects, all with a low sampling rate. SP-ILC has potential for effective use in remote sensing, medical diagnosis and treatment, security, and autonomous vehicle control.
Going Deeper into OSNR Estimation with CNN
Authors: Shen Fangqi , Zhou Jing , Huang Zhiping , Li Longqing
Published: September 2021

As optical performance monitoring (OPM) requires accurate and robust solutions to tackle the increasing dynamic and complicated optical network architectures, we experimentally demonstrate an end-to-end optical signal-to-noise (OSNR) estimation method based on the convolutional neural network (CNN), named OptInception. The design principles of the proposed scheme are specified. The idea behind the combination of the Inception module and finite impulse response (FIR) filter is elaborated as well. We experimentally evaluate the mean absolute error (MAE) and root-mean-squared error (RMSE) of the OSNR monitored in PDM-QPSK and PDM-16QAM signals under various symbol rates. The results suggest that the MAE reaches as low as 0.125 dB and RMSE is 0.246 dB in general. OptInception is also proved to be insensitive to the symbol rate, modulation format, and chromatic dispersion. The investigation of kernels in CNN indicates that the proposed scheme helps convolutional layers learn much more than a lowpass filter or bandpass filter. Finally, a comparison in performance and complexity presents the advantages of OptInception.
Above- and Below-Ground Carbon Storage of Hydrologically Altered Mangrove Wetlands in Puerto Rico after a Hurricane
Authors: Griffiths Lauren N. , Hernandez Elix , Cuevas Elvira , Mitsch William J.
Published: September 2021

Mangrove wetlands are important ecosystems, yet human development coupled with climate change threatens mangroves and their large carbon stores. This study seeks to understand the soil carbon dynamics in hydrologically altered mangrove swamps by studying aboveground biomass estimates and belowground soil carbon concentrations in mangrove swamps with high, medium, and low levels of disturbance in Cataño, Jobos Bay, and Vieques, Puerto Rico. All three sites were affected by hurricane María in 2017, one year prior to the study. As a result of being hit by the Saffir-Simpson category 4 hurricane, the low-disturbance site had almost no living mangroves left during sampling. There was no correlation between level of hydrologic alteration and carbon storage, rather different patterns emerged for each of the three sites. At the highly disturbed location, belowground carbon mass averaged 0.048 ± 0.001 g-C cm−3 which increased with increased aboveground biomass. At the moderately disturbed location, belowground carbon mass averaged 0.047 ± 0.003 g-C cm−3 and corresponded to distance from open water. At the low-disturbed location, organic carbon was consistent between all sites and inorganic carbon concentrations controlled total carbon mass which averaged 0.048 ± 0.002 g-C cm−3. These results suggest that mangroves are adaptive and resilient and have the potential to retain their carbon storage capacities despite hydrologic alterations, but mass carbon storage within mangrove forests can be spatially variable in hydrologically altered conditions.