bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomolecule-Enabled Liquid Separation Membranes: Potential and Recent Progress
Authors: Azmi Faiz Izzuddin , Goh Pei Sean , Ismail Ahmad Fauzi , Hilal Nidal , Wong Tuck Whye , Misson Mailin
Published: January 2022

The implementation of membrane surface modification to enhance the performance of membrane-based separation has become a favored strategy due to its promise to address the trade-off between water permeability and salt rejection as well as to improve the durability of the membranes. Tremendous work has been committed to modifying polymeric membranes through physical approaches such as surface coating and ontology doping, as well as chemical approaches such as surface grafting to introduce various functional groups to the membrane. In the context of liquid separation membranes applied for desalination and water and wastewater treatment, biomolecules have gained increasing attention as membrane-modifying agents due to their intriguing structural properties and chemical functionalities. Biomolecules, especially carbohydrates and proteins, exhibit attractive features, including high surface hydrophilicity and zwitterionic and antimicrobial properties that are desired for liquid separation membranes. In this review, we provide an overview of the recent developments in biomolecule-enabled liquid separation membranes. The roles and potentials of some commonly explored biomolecules in heightening the performance of polymeric membranes are discussed. With the advancements in material synthesis and the need to answer the call for more sustainable materials, biomolecules could serve as attractive alternatives for the development of high-performance composite membranes.
Factors Influencing the Formation of Salicylic Acid by Bipolar Membranes Electrodialysis
Authors: Medina-Collana Juan Taumaturgo , Rosales-Huamani Jimmy Aurelio , Franco-Gonzales Elmar Javier , Montaño-Pisfil Jorge Alberto
Published: January 2022

Salicylic acid is an intermediate product in the synthesis of dyes, medications and aspirin. An electrodialysis module has been constructed with commercial cationic, anionic and bipolar membranes for the conversion of sodium salicylate into salicylic acid. The effect of operating conditions such as applied electric potential, salt concentration, initial acid concentration and volumetric flow on bipolar membrane electrodialysis (BMED) yields were investigated using Taguchi analysis. The results obtained in 210 min of work show an average concentration of salicylic acid of 0.0185 M, an average electric current efficiency of 85.3%, and a specific energy consumption of 2.24 kWh/kg of salicylic acid. It was concluded that the proposed bipolar membrane electrodialysis process is an efficient alternative to produce salicylic acid (SAH) from sodium salicylate (SANa) in an environmentally friendly manner. Furthermore, the production of sodium hydroxide was obtained as a by-product of the process carried out.
Trafficking of Annexins during Membrane Repair in Human Skeletal Muscle Cells
Authors: Croissant Coralie , Gounou Céline , Bouvet Flora , Tan Sisareuth , Bouter Anthony
Published: January 2022

Defects in membrane repair contribute to the development of muscular dystrophies, such as Miyoshi muscular dystrophy 1, limb girdle muscular dystrophy (LGMD), type R2 or R12. Deciphering membrane repair dysfunctions in the development of muscular dystrophies requires precise and detailed knowledge of the membrane repair machinery in healthy human skeletal muscle cells. Using correlative light and electron microscopy (CLEM), we studied the trafficking of four members of the annexin (ANX) family, in myotubes damaged by laser ablation. Our data support a model in which ANXA4 and ANXA6 are recruited to the disruption site by propagating as a wave-like motion along the sarcolemma. They may act in membrane resealing by proceeding to sarcolemma remodeling. On the other hand, ANXA1 and A2 exhibit a progressive cytoplasmic recruitment, likely by interacting with intracellular vesicles, in order to form the lipid patch required for membrane resealing. Once the sarcolemma has been resealed, ANXA1 is released from the site of the membrane injury and returns to the cytosol, while ANXA2 remains accumulated close to the wounding site on the cytoplasmic side. On the other side of the repaired sarcolemma are ANXA4 and ANXA6 that face the extracellular milieu, where they are concentrated in a dense structure, the cap subdomain. The proposed model provides a basis for the identification of cellular dysregulations in the membrane repair of dystrophic human muscle cells.
Effect of La Addition on Microstructure and Properties of Al-0.2Fe-0.06Cu Alloy
Authors: Xu Yawu , Peng Zixuan , Ding Dongyan , Zhang Wenlong , Gao Yongjin , Chen Guozhen , Xie Yonglin , Liao Yongqi
Published: January 2022

The increasing application of lithium-ion batteries has led to higher requirements being imposed on the performance of current collectors. In this work, the effect of La content on the microstructure and properties of Al-0.2Fe-0.06Cu alloy was invested through optical microscopy, scanning electron microscopy and mechanical/electrical/electrochemical performance tests. Experimental results indicated that the addition of La was beneficial to grain refinement and promote the formation of La-containing compounds. However, excessive La addition weakened the refinement effect. Grain refinement played a major role in affecting the mechanical properties of the alloy, but had little effect on the conductivity. In comparison with Al-0.2Fe-0.06Cu, the La-containing alloys had lower corrosion potential, which indicated that the addition of La element could improve the corrosion resistance of the Al-0.2Fe-0.06Cu alloy. The addition of La improved the mechanical properties of the alloy at room temperature and 50 °C. When the La addition was 0.1wt.%, the alloy had the best mechanical properties. The corrosion resistance of the alloy continued to improve with increases in the La content.
Influence of Sintering Temperature on the Structural, Morphological, and Electrochemical Properties of NiO-YSZ Anode Synthesized by the Autocombustion Route
Authors: Irshad Muneeb , Rafique Muhammad , Tabish Asif Nadeem , Ghaffar Abdul , Shakeel Ahmad , Siraj Khurram , Ain Qurat ul , Raza Rizwan , Assiri Mohammed Ali , Imran Muhammad
Published: January 2022

In this study, nickel oxide–Y2O3-doped ZrO2 (NiO-YSZ) composite powder as an anode material was synthesized using a cost-effective combustion method for high-temperature solid oxide fuel cell (SOFC). Further, the effects of sintering temperatures (1200, 1300, and 1400 °C) were studied for its properties in relation to the SOFC performance. The prepared and sintered NiO-YSZ materials were characterized for their surface morphology, composition, structure, and conductivity. The cubic crystalline nature of NiO and YSZ was sufficed by X-ray diffraction, and SEM images revealed an increase in the densification of microstructure by an increase in the sintering temperature. EDX spectrum confirmed the presence of nickel, yttrium, and zirconia without any impurity. Conductivity measurements, under a hydrogen environment, revealed that NiO-YSZ, sintered at 1400 °C, exhibits better conductivity compared to the samples sintered at lower temperatures. Electrochemical performance of button-cells was also evaluated and peak power density of 0.62 Wcm−2 is observed at 800 °C. The citrate combustion method provided peak performance for cells containing anode sintered at 1200 °C, which was previously reported at higher sintering temperatures. Therefore, the citrate combustion method is found to be a suitable route to synthesize NiO-YSZ at low sintering temperature.
Effects of Zn Addition on the Microstructure and Mechanical Properties of As-Extruded Mg-2Al-0.5Ca Alloy
Authors: Yuan Ming , He Chao , Song Yan , Lei Bin , Qian Xiaoying , Dong Zhihua , Zhao Jun , Yang Huabao , Chai Yanfu , Jiang Bin , Pan Fusheng
Published: January 2022

The effects of Zn addition on the microstructure and tensile properties of as-extruded Mg-2Al-0.5Ca-xZn (x = 0, 0.3, 0.6, 0.9 wt.%) alloys were investigated in this work. The results showed that the extruded sheets exhibited a completely dynamically recrystallized microstructure, the grain size was refined, and texture weakening was achieved with Zn addition because of the segregation of Zn atoms on grain boundaries, which suppresses the growth of dynamic recrystallized grains. The addition of 0.6 wt.% Zn improved both the tensile strength and ductility of the as-extruded Mg-2Al-0.5Ca alloy. The as-extruded Mg-2Al-0.5Ca-0.6Zn alloy showed a 0.2% proof stress of 145 MPa, an ultimate tensile strength of 317 MPa, and an elongation of 30.0% along the extruded direction. The simultaneous improvement of strength and ductility was mainly due to the fine and homogeneous grain microstructure and the weakened extrude direction (ED)-tilted texture. The as-extruded Mg-2Al-0.5Ca-0.6Zn alloy showed little in-plane anisotropic tensile properties, with a 0.2% proof stress, ultimate tensile strength, and elongation in the 45° direction of 148 MPa, 299 MPa, and 25.0%, and those in the transverse direction of 148 MPa, 269 MPa, and 16.8%, respectively.
Metallic Materials and Their Applications in Aerospace and Advanced Technologies
Authors: Arrigoni Michel
Published: January 2022

Exploring the mysteries of the universe, transporting people over longer distances in the safest way, providing energy to a growing global population, and facing environmental changes are among the major challenges that will face humanity in the coming decades: Satellite observations have become essential in monitoring the ecological health of the Earth, but they require space launches that raise the paradox of greenhouse and toxic gases rejection by the use of solid propellants [...]
Molecular Mechanisms of Parathyroid Disorders in Chronic Kidney Disease
Authors: Hassan Alia , Khalaily Nareman , Kilav-Levin Rachel , Nechama Morris , Volovelsky Oded , Silver Justin , Naveh-Many Tally
Published: January 2022

Secondary hyperparathyroidism (SHP) is a common complication of chronic kidney disease (CKD) that induces morbidity and mortality in patients. How CKD stimulates the parathyroid to increase parathyroid hormone (PTH) secretion, gene expression and cell proliferation remains an open question. In experimental SHP, the increased PTH gene expression is post-transcriptional and mediated by PTH mRNA–protein interactions that promote PTH mRNA stability. These interactions are orchestrated by the isomerase Pin1. Pin1 participates in conformational change-based regulation of target proteins, including mRNA-binding proteins. In SHP, Pin1 isomerase activity is decreased, and thus, the Pin1 target and PTH mRNA destabilizing protein KSRP fails to bind PTH mRNA, increasing PTH mRNA stability and levels. An additional level of post-transcriptional regulation is mediated by microRNA (miRNA). Mice with parathyroid-specific knockout of Dicer, which facilitates the final step in miRNA maturation, lack parathyroid miRNAs but have normal PTH and calcium levels. Surprisingly, these mice fail to increase serum PTH in response to hypocalcemia or uremia, indicating a role for miRNAs in parathyroid stimulation. SHP often leads to parathyroid hyperplasia. Reduced expressions of parathyroid regulating receptors, activation of transforming growth factor α-epidermal growth factor receptor, cyclooxygenase 2-prostaglandin E2 and mTOR signaling all contribute to the enhanced parathyroid cell proliferation. Inhibition of mTOR by rapamycin prevents and corrects the increased parathyroid cell proliferation of SHP. This review summarizes the current knowledge on the mechanisms that stimulate the parathyroid cell at multiple levels in SHP.
Effects of pH and Osmotic Changes on the Metabolic Expressions of Bacillus subtilis Strain 168 in Metabolite Pathways including Leucine Metabolism
Authors: Park Min-Kyung , Lee Soyeon , Kim Young-Suk
Published: January 2022

Bacillus subtilis is often exposed to diverse culture conditions with the aim of improving hygiene or food quality. This can lead to changes in the volatile metabolite profiles related to the quality of fermented foods. To comprehensively interpret the associated metabolic expressions, changes in intracellular primary and extracellular secondary volatile metabolites were investigated by exposing B. subtilis to an alkaline pH (BP, pH 8.0) and a high salt concentration (BS, 1 M). In particular, B. subtilis was cultured in a leucine-enriched medium to investigate the formation of leucine-derived volatile metabolites. This study observed metabolic changes in several metabolic pathways, including carbohydrate metabolism, amino acid metabolism, fatty acid metabolism, and leucine degradation. The formation of proline (an osmolyte), furans, pyrrole, and monosaccharide sugars (glucose, galactose, and fructose) was enhanced in BS, whereas fatty acid derivatives (ketones and alcohols) increased in BP. In the case of leucine degradation, 3-methyl-butanal and 3-methylbutanol could be salt-specific metabolites, while the contents of 3-methylbutanoic acid and 3-methylbutylacetate increased in BP. These results show culture condition-specific metabolic changes, especially secondary volatile metabolites related to the sensory property of foods, in B. subtilis.
Optimisation of the HS-SPME/GC-MS Approach by Design of Experiments Combined with Chemometrics for the Classification of Cretan Virgin Olive Oils
Authors: Lioupi Artemis , Sampsonidis Ioannis , Virgiliou Christina , Papoti Vassiliki T. , Zinoviadou Kyriaki G. , Spyros Apostolos , Theodoridis Georgios
Published: January 2022

A headspace-solid phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) method was developed herein for the analysis of virgin olive oil volatile metabolome. Optimisation of SPME conditions was performed by Design of Experiments (DoE) and Response Surface Methodology (RSM) approaches and factors, such as sample volume, sample stirring, extraction temperature and time, and desorption temperature and time, were examined to reach optimal microextraction conditions. The potential of the optimised method was then investigated for its use in the classification of Cretan virgin olive oil samples with the aid of multivariate statistical analysis. Certain markers were identified with significance in the geographical classification of Cretan extra-virgin olive oil (EVOO) samples. In total, 92 volatile organic compounds were tentatively identified and semi-quantified, and the data obtained confirm that the method is robust, reliable, and analytically powerful for olive oil classification.
In Vitro Metabolic Study of Four Synthetic Cathinones: 4-MPD, 2-NMC, 4F-PHP and bk-EPDP
Authors: Gavrilović Ivana , Gelu Yunita , Abbate Vincenzo
Published: January 2022

The use of illicit drugs is exceedingly prevalent in society, and several of them can be illegally purchased from the internet. This occurrence is particularly augmented by the rapid emergence of novel psychoactive substances (NPS), which are sold and distributed as “legal highs”. Amongst NPS, the class of synthetic cathinones represents stimulant substances exhibiting similar effects to amphetamine and its derivatives. Despite potentially being less psychoactive than amphetamine, synthetic cathinones are harmful substances for humans, and little or no information is available regarding their pharmacology and toxicology. The present study investigated the in vitro metabolism and metabolites of four recent synthetic cathinones, namely, 1-(4-methylphenyl)-2-(methylamino)-pentanone (4-MPD), 1-(4-methylphenyl)-2-dimethylamino-propanone (2-NMC), 1-(4-fluorophenyl)-2-(pyrrolidin-1-yl-hexanone (4F-PHP) and 1-(1,3-benzodioxol-5-yl)-2-(ethylamino)-1-pentanone (bk-EPDP). Our in vitro metabolism study resulted in 24 identified metabolites, including both phase I and phase II metabolites. All metabolites were detected and identified using liquid chromatography–high-resolution mass spectrometry and may serve as additional markers of abuse of these NPS in toxicological analyses.
TransDiscovery: Discovering Biotransformation from Human Microbiota by Integrating Metagenomic and Metabolomic Data
Authors: Yan Donghui , Cao Liu , Zhou Muqing , Mohimani Hosein
Published: January 2022

The human microbiome is a complex community of microorganisms, their enzymes, and the molecules they produce or modify. Recent studies show that imbalances in human microbial ecosystems can cause disease. Our microbiome affects our health through the products of biochemical reactions catalyzed by microbial enzymes (microbial biotransformations). Despite their significance, currently, there are no systematic strategies for identifying these chemical reactions, their substrates and molecular products, and their effects on health and disease. We present TransDiscovery, a computational algorithm that integrates molecular networks (connecting related molecules with similar mass spectra), association networks (connecting co-occurring molecules and microbes) and knowledge bases of microbial enzymes to discover microbial biotransformations, their substrates, and their products. After searching the metabolomics and metagenomics data from the American Gut Project and the Global Foodomic Project, TranDiscovery identified 17 potentially novel biotransformations from the human gut microbiome, along with the corresponding microbial species, substrates, and products.
Investigation of Twelve Significant Mycotoxin Contamination in Nut-Based Products by the LC–MS/MS Method
Authors: Er Demirhan Buket , Demirhan Burak
Published: January 2022

In this study, a total of 80 peanut butter, hazelnut butter, and chocolate samples were obtained from local markets in Ankara, Turkey. These foods were analyzed for twelve toxicological important mycotoxins, such as aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), and aflatoxin G2 (AFG2); fumonisin B1 (FB1) and fumonisin B2 (FB2); ochratoxin A (OTA); sterigmatocystin (STE); deoxynivalenol (DON); zearalenone (ZON); T-2 toxin (T2); and HT-2 toxin (HT2) by the LC–MS/MS multi-mycotoxin method. In addition to this analysis, the presence of total aerobic mesophilic bacteria was investigated in the samples. The samples were analyzed microbiologically using standard procedures. Finally, the minimum and maximum levels of AFB1, AFB2, AFG1, FB2, OTA, STE, DON, ZON, T2, and HT2 in the samples were found to be 0.04–27.37 µg/kg, 0.06–6.19 µg/kg, 0.14–0.40 µg/kg, 2.73–2.93 µg/kg, 0.01–37.26 µg/kg, 0.19–2.25 µg/kg, 11.81–42.09 µg/kg, 0.03–7.57 µg/kg, 1.41–2.54 µg/kg, and 6.94–7.43 µg/kg, respectively. AFG2 and FB1 were not detected in any of the samples. The most frequently detected mycotoxins in analyzed samples were OTA (78.75%) and AFB1 (75%). In addition, total aerobic mesophilic bacteria were isolated from 53.75% of samples. Some of the tested food samples contained mycotoxins above the Turkish Food Codex maximum limit.
Single-Beam Acoustic Tweezer Prepared by Lead-Free KNN-Based Textured Ceramics
Authors: Quan Yi , Fei Chunlong , Ren Wei , Wang Lingyan , Zhao Jinyan , Zhuang Jian , Zhao Tianlong , Li Zhaoxi , Zheng Chenxi , Sun Xinhao , Zheng Kun , Wang Zhe , Ren Matthew Xinhu , Niu Gang , Zhang Nan , Karaki Tomoaki , Jiang Zhishui , Wen Li
Published: January 2022

Acoustic tweezers for microparticle non-contact manipulation have attracted attention in the biomedical engineering field. The key components of acoustic tweezers are piezoelectric materials, which convert electrical energy to mechanical energy. The most widely used piezoelectric materials are lead-based materials. Because of the requirement of environmental protection, lead-free piezoelectric materials have been widely researched in past years. In our previous work, textured lead-free (K, Na)NbO3 (KNN)-based piezoelectric ceramics with high piezoelectric performance were prepared. In addition, the acoustic impedance of the KNN-based ceramics is lower than that of lead-based materials. The low acoustic impedance could improve the transmission efficiency of the mechanical energy between acoustic tweezers and water. In this work, acoustic tweezers were prepared to fill the gap between lead-free piezoelectric materials research and applications. The tweezers achieved 13 MHz center frequency and 89% −6 dB bandwidth. The −6 dB lateral and axial resolution of the tweezers were 195 μm and 114 μm, respectively. Furthermore, the map of acoustic pressure measurement and acoustic radiation calculation for the tweezers supported the trapping behavior for 100 μm diameter polystyrene microspheres. Moreover, the trapping and manipulation of the microspheres was achieved. These results suggest that the KNN-based acoustic tweezers have a great potential for further applications.
Improving Breakdown Voltage and Threshold Voltage Stability by Clamping Channel Potential for Short-Channel Power p-GaN HEMTs
Authors: Wang Hongyue , Shi Yijun , Xin Yajie , Liu Chang , Lu Guoguang , Huang Yun
Published: January 2022

This paper proposes a novel p-GaN HEMT (P-HEMT) by clamping channel potential to improve breakdown voltage (BV) and threshold voltage (VTH) stability. The clamping channel potential for P-HEMT is achieved by a partially-recessed p-GaN layer (PR p-GaN layer). At high drain bias, the two-dimensional electron gas (2DEG) channel under the PR p-GaN layer is depleted to withstand the drain bias. Therefore, the channel potential at the drain-side of the p-GaN layer is clamped to improve BV and VTH stability. Compared with the conventional p-GaN HEMT (C-HEMT), simulation results show that the BV is improved by 120%, and the VTH stability induced by high drain bias is increased by 490% for the same on-resistance. In addition, the influence of the PR p-GaN layers’ length, thickness, doping density on BV and VTH stability is analyzed. The proposed device can be a good reference to improve breakdown voltage and threshold voltage stability for short-channel power p-GaN HEMTs.
Acknowledgment to Reviewers of Micromachines in 2021
Authors:   Micromachines Editorial Office
Published: January 2022

Rigorous peer-reviews are the basis of high-quality academic publishing [...]
Modeling and Position Control Simulation Research on Shape Memory Alloy Spring Actuator
Authors: Hu Bingshan , Liu Fengchen , Mao Binghao , Chen Zhiwei , Yu Hongliu
Published: January 2022

The shape memory alloy (SMA) actuator is widely used in aerospace, medical and robot fields because of its advantages of low driving voltage, large driving force, no noise and high-power–weight ratio. Therefore, it is of great significance to establish the theoretical model of the SMA actuator and analyze the driving characteristics of the SMA actuator. On the basis of summarizing the constitutive model of the shape memory alloy spring, the phase transformation dynamics model of SMA including the minor hysteresis loop is established using the Duhem model in this paper, and the theoretical models of the bias and differential SMA spring actuator are established. At the same time, a PID position controller including anti-saturation and anti-overheating functions is proposed to control the position of the SMA actuator. Finally, the position control simulation model of the SMA spring actuator is established and simulated. Simulation results show that the position of the SMA actuator can be well controlled by using the model and control method established in this paper.
Editorial for the Special Issue on Emerging and Disruptive Next-Generation Technologies for POC: Sensors, Chemistry and Microfluidics for Diagnostics
Authors: Ferrara Francesco , Primiceri Elisabetta , Chiriacò Maria Serena
Published: January 2022

Recently, the attention paid to self-care tests and the need for easy and large-scale screenings of a high number of people has dramatically increased [...]
Numerical Simulations of Magnetohydrodynamics Natural Convection and Entropy Production in a Porous Annulus Bounded by Wavy Cylinder and Koch Snowflake Loaded with Cu–Water Nanofluid
Authors: Mourad Abed , Abderrahmane Aissa , Younis Obai , Marzouki Riadh , Alazzam Anas
Published: January 2022

The current paper presents a numerical study of the magnetohydrodynamics natural convection and entropy production of Cu–water nanofluid contained in a porous annulus between a heated Koch snowflake and wavy cylinder with lower temperature with respect to the Koch snowflake. The numerical algorithm is based on the Galerkin Finite Element Method. The impacts of Rayleigh number (Ra = 103, 104, 105, and 106), Hartman number (Ha = 0, 25, 50, and 100), Darcy number (Da = 10−2, 10−3, 10−4, and 10−5), nanoparticle volumetric fraction (φ = 2%, 3%, 4%, and 5%), and the undulations number of the outer wavy cylinder (three cases) on the distributions of isotherms, streamlines, mean Nusselt number (Nuavg), as well as on total entropy production and Bejan number are thoroughly examined. The computational outcomes disclose that dispersing more Cu nanoparticles in the base fluid and creating a flow with higher intensity inside the annulus by raising the Rayleigh number bring about a boosted natural convective flow in the cavity, which improves the heat transmission rate. In addition, it can be noted that owing to the peculiar form of the heated Koch snowflake, nanofluid gets trapped between the angled parts, resulting in uneven temperature profiles with higher values in these places.
Molecular Diagnosis, Antimicrobial Resistance Profiles and Disease Patterns of Gram-Positive Pathogens Recovered from Clinical Infections in Major Ha’il Hospitals
Authors: Said Kamaleldin B. , Alsolami Ahmed , Khalifa Amany M. , Khalil Nuha A. , Moursi Soha , Rakha Ehab , Osman Abuzar , Rashidi Musleh , Taha Taha E. , Bashir Abdelhafiz I. , Moussa Safia , Al Jadani Ahmed , Nagi Hatem , Kuddus Mohammad , Alrashedi Obaid M. , Alharbi Amar S. , Alfaraj Abdulrahman , Mustafa Roba ,   on behalf of the Ha’il COM Research Unit Group
Published: January 2022

Nosocomial resistance in staphylococci and enterococci is challenging. The aim of this work was to conduct a multipoint study using molecular detections, antimicrobial resistances profiles, patient demographics and disease patterns for objective assessments of Staphilococcus aureus and other Gram-positive pathogens recovered from clinical infections in the Ha’il region. We have surveyed 188 non-duplicate Gram-positives against 22 antimicrobials for molecular-differentiation, resistance, patient demographics, and disease patterns from January–April 2021. According to definitions for acquired resistance, Staphylococcus aureus was the most frequent with multidrug resistant (65.4%), where MRSA was 60% (n = 72 out of 121). In age-identified patients, 43% were seniors ≥50 years, 38% 21–49 years, and 19% 0–20 years. In gender-identified patients, 63% were males, and 37% were females. While 25% of specimens were from the ICU, the majority (60%) of specimens were from surgical infection in other wards. Staphylococcus epidermidis was the second (15.4%) species of infection identified with 81% from bloodstream infections at the ICU and other wards. The majority of S. epidermidis patients (69%) were seniors ≥50 years, while other age groups 0–20 and 21–49 each had 14% isolates. Although S. epidermidis was multidrug-resistant, it was susceptible to many drugs. Enterococcus faecalis (13%) ranked third with two major infections; bloodstream (64%) and urinary-tract infections (36%) in mainly seniors (86%). Its isolates were fully resistant to oxacillin, penicillin, cefoxitin, and cefotaxime but nearly 100% susceptible to seven others. Other Gram-positive bacteria (6%) were susceptible to many antibiotics. The use of combinations of objective criteria is a well thought out approach in infection control. While the low-frequency of Gram-positives is an impressive achievement, future large-scale investigations should include all private hospitals, clinics and other cities over a longer sampling time to gain more insights. Although geriatric susceptibility can be justified by age and comorbidities, the staphylococcal infections in young adults and children is a global concern and warrants more vertical studies.
Legionella pneumophila—Virulence Factors and the Possibility of Infection in Dental Practice
Authors: Talapko Jasminka , Frauenheim Erwin , Juzbašić Martina , Tomas Matej , Matić Suzana , Jukić Melita , Samardžić Marija , Škrlec Ivana
Published: January 2022

Legionella pneumophila is defined as a bacterium that can cause severe pneumonia. It is found in the natural environment and in water, and is often found in water tanks. It can be an integral part of biofilms in nature, and the protozoa in which it can live provide it with food and protect it from harmful influences; therefore, it has the ability to move into a sustainable but uncultured state (VBNC). L. pneumophila has been shown to cause infections in dental practices. The most common transmission route is aerosol generated in dental office water systems, which can negatively affect patients and healthcare professionals. The most common way of becoming infected with L. pneumophila in a dental office is through water from dental instruments, and the dental unit. In addition to these bacteria, patients and the dental team may be exposed to other harmful bacteria and viruses. Therefore, it is vital that the dental team regularly maintains and decontaminates the dental unit, and sterilizes all accessories that come with it. In addition, regular water control in dental offices is necessary.
The Arginine Catabolism-Derived Amino Acid l-ornithine Is a Chemoattractant for Pseudomonas aeruginosa
Authors: Dhodary Basanta , Sampedro Inmaculada , Behroozian Shekooh , Borza Victor , Her Stephanie , Hill Jane E.
Published: January 2022

Pseudomonas aeruginosa is a common, opportunistic bacterial pathogen among patients with cystic fibrosis, asthma, and chronic obstructive pulmonary disease. During the course of these diseases, l-ornithine, a non-proteinogenic amino acid, becomes more abundant. P. aeruginosa is chemotactic towards other proteinogenic amino acids. Here, we evaluated the chemotaxis response of P. aeruginosa towards l-ornithine. Our results show that l-ornithine serves as a chemoattractant for several strains of P. aeruginosa, including clinical isolates, and that the chemoreceptors involved in P. aeruginosa PAO1 are PctA and PctB. It seems likely that P. aeruginosa’s chemotactic response to l-ornithine might be a common feature and thus could potentially contribute to pathogenesis processes during colonization and infection scenarios.
Predictive Potential of MALDI-TOF Analyses for Wine and Brewing Yeast
Authors: Zhang Junwen , Plowman Jeffrey E. , Tian Bin , Clerens Stefan , On Stephen L. W.
Published: January 2022

The potential of MALDI-TOF profiling for predicting potential applications of yeast strains in the beverage sector was assessed. A panel of 59 commercial yeasts (47 wine and 12 brewing yeasts) was used to validate the concept whereby 2 culture media (YPD agar and YPD broth), as well as two mass ranges m/z 500–4000 and m/z 2000–20,000, were evaluated for the best fit. Three machine learning-based algorithms, PCA, MDS, and UMAP, in addition to a hierarchical clustering method, were employed. Profiles derived from broth cultures yielded more peaks, but these were less well-defined compared with those from agar cultures. Hierarchical clustering more clearly resolved different species and gave a broad overview of potential strain utility, but more nuanced insights were provided by MDS and UMAP analyses. PCA-based displays were less informative. The potential of MALDI-TOF proteomics in predicting the utility of yeast strains of commercial benefit is supported in this study, provided appropriate approaches are used for data generation and analysis.
First Case of a COVID-19 Patient Infected by Delta AY.4 with a Rare Deletion Leading to a N Gene Target Failure by a Specific Real Time PCR Assay: Novel Omicron VOC Might Be Doing Similar Scenario?
Authors: Alkhatib Mohammad , Bellocchi Maria Concetta , Marchegiani Greta , Grelli Sandro , Micheli Valeria , Stella Daniele , Zerillo Bartolomeo , Carioti Luca , Svicher Valentina , Rogliani Paola , Ceccherini-Silberstein Francesca
Published: January 2022

Herein, we report a case of an Italian male infected by Delta sublineage AY.4 harboring an atypical deletion, leading to a N gene target failure (NGTF) by a commercial molecular assay for SARS-CoV-2 diagnosis (AllplexTM SARS-CoV-2 Assay, Seegene). A 59-year-old unvaccinated patient was hospitalized for pulmonary embolism, with first negative results obtained by both molecular and antigen tests. After several days of viral negativity, he presented positive results for E and RdRP/S genes, but negative in N gene. Negativity in N gene was repeatedly confirmed in the following days. Suspecting an infection by the Omicron variant, SARS-CoV-2 genome sequencing was rapidly performed from nasopharyngeal swab by MiSeq and revealed the presence of the Delta sublineage AY.4 variant with an atypical deletion of six nucleotides, leading to G214-G215 deletion in the Nucleocapsid, thus responsible for NGTF. The analysis of GISAID sequences (N = 2,618,373 12 January 2022) showed that G214-G215 deletion is rarely occurring in most circulating Delta lineages and sublineages in the globe and Europe, with an overall prevalence never exceeding 0.2%. Hence, this study highlights the importance to perform SARS-CoV-2 sequencing and to characterize novel mutations/deletions that could jeopardize the proper interpretation of molecular diagnostic tests. Based on these assumptions, the role of deletions in the recently identified Omicron variant deserves further investigation.
Novel Methanobacterium Strain Induces Severe Corrosion by Retrieving Electrons from Fe0 under a Freshwater Environment
Authors: Hirano Shin-ichi , Ihara Sota , Wakai Satoshi , Dotsuta Yuma , Otani Kyohei , Kitagaki Toru , Ueno Fumiyoshi , Okamoto Akihiro
Published: January 2022

Methanogens capable of accepting electrons from Fe0 cause severe corrosion in anoxic conditions. In previous studies, all iron-corrosive methanogenic isolates were obtained from marine environments. However, the presence of methanogens with corrosion ability using Fe0 as an electron donor and their contribution to corrosion in freshwater systems is unknown. Therefore, to understand the role of methanogens in corrosion under anoxic conditions in a freshwater environment, we investigated the corrosion activities of methanogens in samples collected from groundwater and rivers. We enriched microorganisms that can grow with CO2/NaHCO3 and Fe0 as the sole carbon source and electron donor, respectively, in ground freshwater. Methanobacterium sp. TO1, which induces iron corrosion, was isolated from freshwater. Electrochemical analysis revealed that strain TO1 can uptake electrons from the cathode at lower than −0.61 V vs SHE and has a redox-active component with electrochemical potential different from those of other previously reported methanogens with extracellular electron transfer ability. This study indicated the corrosion risk by methanogens capable of taking up electrons from Fe0 in anoxic freshwater environments and the necessity of understanding the corrosion mechanism to contribute to risk diagnosis.
New Wild-Type Lacticaseibacillus rhamnosus Strains as Candidates to Manage Type 1 Diabetes
Authors: Nelios Grigorios , Santarmaki Valentini , Pavlatou Chrysoula , Dimitrellou Dimitra , Kourkoutas Yiannis
Published: January 2022

The incidence of type 1 diabetes (T1D) has been dramatically increased in developed countries, and beyond the genetic impact, environmental factors, including diet, seem to play an important role in the onset and development of the disease. In this vein, five Lacticaseibacillus rhamnosus, isolated from traditional fermented Greek products, were screened for potential probiotic properties, aiming at maintaining gut homeostasis and antidiabetic capability to alleviate T1D symptoms. L. rhamnosus cell-free supernatants induced strong growth inhibitory activity against common food spoilage and foodborne pathogenic microorganisms, associated with several diseases, including T1D, and were also able to inhibit α-glucosidase activity (up to 44.87%), a promising property for alternatives to the antidiabetic drugs. In addition, survival rates up to 36.76% were recorded during the application of the static in vitro digestion model. The strains had no hemolytic activity and were sensitive to common antibiotics suggested by the European Food and Safety Association, apart from chloramphenicol. However, it is highly unlikely that the resistance has been acquired. In conclusion, our results suggest a great health-promoting potential of the newly isolated wild-type L. rhamnosus strains, but further confirmation of their efficiency in experimental animal models is considered an essential next research step.
Genome Sequence and Assessment of Safety and Potential Probiotic Traits of Lactobacillus johnsonii CNCM I-4884
Authors: Boucard Anne-Sophie , Florent Isabelle , Polack Bruno , Langella Philippe , Bermúdez-Humarán Luis G.
Published: January 2022

The probiotic strain Lactobacillus johnsonii CNCM I-4884 exhibits anti-Giardia activity in vitro and in vivo in a murine model of giardiasis. The aim of this study was the identification and characterization of the probiotic potential of L. johnsonii CNCM I-4884, as well as its safety assessment. This strain was originally classified as Lactobacillus gasseri based on 16S gene sequence analysis. Whole genome sequencing led to a reclassification as L. johnsonii. A genome-wide search for biosynthetic pathways revealed a high degree of auxotrophy, balanced by large transport and catabolic systems. The strain also exhibits tolerance to low pH and bile salts and shows strong bile salt hydrolase (BSH) activity. Sequencing results revealed the absence of antimicrobial resistance genes and other virulence factors. Phenotypic tests confirm that the strain is susceptible to a panel of 8 antibiotics of both human and animal relevance. Altogether, the in silico and in vitro results confirm that L. johnsonii CNCM I-4884 is well adapted to the gastrointestinal environment and could be safely used in probiotic formulations.
Application of Bioorganic Fertilizer on Panax notoginseng Improves Plant Growth by Altering the Rhizosphere Microbiome Structure and Metabolism
Authors: Shi Rui , Wang Shu , Xiong Bingjie , Gu Haiyan , Wang Huiling , Ji Chao , Jia Weijia , Horowitz Abraham Rami , Zhen Wenjie , Asher Jiftah Ben , He Xiahong
Published: January 2022

Bioorganic fertilizers can alleviate (a) biotic stresses and sustainably increase crop yields. The effect of bioorganic fertilizers on the rhizosphere bacterial community of Panax notoginseng and soil metabolism remains unknown. Here, we tracked the changes in the soil physicochemical properties, bacterial microbiota responses, and soil metabolic functions after the addition of a bioorganic fertilizer in a P. notoginseng field. The application of a bioorganic fertilizer reduced the soil acidification, improved the organic matter, and increased the contents of the total/available soil nutrients. Soil amendment with a bioorganic fertilizer significantly affected the structure of the rhizosphere bacterial community, leading to the enrichment of specific bacterial consortia such as Rhodanobacter, Arthrobacter, Sphingomonas, Devosia, Pseudolabrys, Luteimonas, Lysobacter, Nitrosospira, and Nakamurella. Previously, many of these genera have been associated with nutrient cycling, plant productivity, and disease suppression. Metabolome analysis further highlighted that the bioorganic fertilizer treatment significantly reduced phenolic acids and flavonoids and enhanced organic acids, saccharides and alcohols, and amino acids. This result indicates a high survival of bacterial microbiota in the rhizosphere and an availability of nutrients for P. notoginseng growth. This work showed that the application of bioorganic fertilizers significantly improves soil health status, alters soil metabolic functions, and stimulates a specific subset of rhizosphere microbiota for nutrient cycling and disease protection in P. notoginseng.
Evaluation of an Indirect Immunofluorescence Assay for the Detection of Anaplasma phagocytophilum Antigen in Ovine Buffy Coat Smears
Authors: Athanasiou Labrini V. , Tsokana Constantina N. , Katsogiannou Eleni G. , Boutsini Sofia , Katsoulos Panagiotis D.
Published: January 2022

Diagnosis of anaplasmosis is challenging considering the great variation in clinical signs and the limitations of the available diagnostic assays, while the detection of carrier animals that play a significant role in disease epidemiology as reservoirs is of great significance. In this study, we evaluated the diagnostic accuracy of a newly developed indirect immunofluorescent assay (Ag-IFAT) for the detection of A. phagocytophilum antigens in buffy coat specimens, alone and in combination with cytology, using PCR as a reference. Blood samples were collected from 138 sheep of the Chios breed from six farms in Greece. A buffy coat was extruded from the centrifuged blood. Buffy coat smears were used for cytological examination and the Ag-IFAT assay. The Ag-IFAT assay presented excellent specificity (100%) and high sensitivity (85.4%) for the detection of A. phagocytophilum antigens in buffy coats, and it has an almost perfect agreement with PCR and cytology (κ value = 0.88 and 0.85, respectively). A. phagocytophilum antigens are likely to be detected using Ag-IFAT in a PCR-positive animal, as indicated by the good performance of the assay. Overall, this assay presents high diagnostic accuracy, and it could be used for the detection of animals during the early stage of infection.
Prion-like Domains in Spike Protein of SARS-CoV-2 Differ across Its Variants and Enable Changes in Affinity to ACE2
Authors: Tetz George , Tetz Victor
Published: January 2022

Currently, the world is struggling with the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Prions are proteins that possess a unique conformational conversion, with the ability to rapidly shift between multiple conformations due to residue hydrophobicity and net sequence charge, and viral prion-like proteins are known as potential regulators of viral infections. However, the prion-like domains (PrD) in the SARS-CoV-2 proteome have not been analyzed. In this in silico study, using the PLAAC algorithm, we identified the presence of prion-like domains in the SARS-CoV-2 spike protein. Compared with other viruses, a striking difference was observed in the distribution of prion-like domains in the spike protein since SARS-CoV-2 is the only coronavirus with a prion-like domain found in the receptor-binding domain of the S1 region of the spike protein. The presence and unique distribution of prion-like domains in the SARS-CoV-2 receptor-binding domains of the spike protein are particularly interesting since although the SARS-CoV-2 and SARS-CoV S proteins share the same host cell receptor, angiotensin-converting enzyme 2 (ACE2), SARS-CoV-2 demonstrates a 10- to 20-fold higher affinity for ACE2. We identified prion-like domains in the α1 helix of the ACE2 receptor that interact with the viral receptor-binding domain of SARS-CoV-2. Finally, we found substantial differences in the prion-like domain of the S1 region of the spike protein across emerging variants including Omicron (B.1.1.529). Taken together, the present findings indicate that the identified PrDs in the SARS-CoV-2 receptor-binding domain (RBD) and ACE2 region that interact with RBD play important functional roles in viral adhesion and entry.
Prospection of Psychrotrophic Filamentous Fungi Isolated from the High Andean Paramo Region of Northern Ecuador: Enzymatic Activity and Molecular Identification
Authors: Brück Stefan Alexander , Contato Alex Graça , Gamboa-Trujillo Paul , de Oliveira Tássio Brito , Cereia Mariana , de Moraes Polizeli Maria de Lourdes Teixeira
Published: January 2022

The isolation of filamentous fungal strains from remote habitats with extreme climatic conditions has led to the discovery of a series of enzymes with attractive properties that can be useful in various industrial applications. Among these, cold-adapted enzymes from fungi with psychrotrophic lifestyles are valuable agents in industrial processes aiming towards energy reduction. Out of eight strains isolated from soil of the paramo highlands of Ecuador, three were selected for further experimentation and identified as Cladosporium michoacanense, Cladosporium sp. (cladosporioides complex), and Didymella sp., this last being reported for the first time in this area. The secretion of seven enzymes, namely, endoglucanase, exoglucanase, β-D-glucosidase, endo-1,4-β-xylanase, β-D-xylosidase, acid, and alkaline phosphatases, were analyzed under agitation and static conditions optimized for the growth period and incubation temperature. Cladosporium strains under agitation as well as incubation for 72 h mostly showed the substantial activation for endoglucanase reaching up to 4563 mU/mL and xylanase up to 3036 mU/mL. Meanwhile, other enzymatic levels varied enormously depending on growth and temperature. Didymella sp. showed the most robust activation at 8 °C for endoglucanase, β-D-glucosidase, and xylanase, indicating an interesting profile for applications such as bioremediation and wastewater treatment processes under cold climatic conditions.
Microbial Consortia Involved in Traditional Sicilian Sourdough: Characterization of Lactic Acid Bacteria and Yeast Populations
Authors: Pino Alessandra , Russo Nunziatina , Solieri Lisa , Sola Laura , Caggia Cinzia , Randazzo Cinzia Lucia
Published: January 2022

Sourdough is one of the oldest starters traditionally used for making baked goods, offering several advantages to the sensory, rheology, and shelf life of final products. The present study investigated, for the first time, the microbiota of spontaneously fermented Maiorca dough samples collected from bakeries located in Sicily (Italy). Four sourdough samples (M1, M2, M3, and M4), were produced using Triticum vulgare Host. var. albidum Koern (Maiorca grain) were subjected to LAB and yeasts isolation and identification at the species level. The in-depth characterization of the lactobacilli population revealed that Lactiplantibacillus plantarum and Levilactobacillus brevis unquestionably dominated the Maiorca sourdough ecosystem. Concerning the yeasts community, high species diversity was found. Saccharomyces cerevisiae and Wickerhamomyces anomalus were the most frequently isolated species. In addition, Torulaspora delbrueckii, Pichia kluyveri, Candida boidinii, and Candida diddensiae were also detected. Investigations on both pro-technological and functional traits of the isolated strains could lead to the selection of starters for the production of baked goods.
Multi-Step Recycling of BF Slag Heat via Biomass for CO2 Mitigation
Authors: Firsbach Felix , Senk Dieter , Babich Alexander
Published: January 2022

Iron- and steelmaking processes create slags, valuable by-products. Industrial utilisation of slag as a lower-value secondary mineral source has been established for decades. Slag heat recovery is an ongoing research topic and has the potential to maximise energy efficiency in iron and steel production. Heat recuperation aims to tap the unused thermal recycling potential of molten slags. This short communication expands the concept for the utilisation of recovered heat for producing torrefied biomass and biogas. The torrefaction process is linked with slag heat recovery and via the BASE method with enhanced blast furnace operation. Such a combination reduces CO2 emissions significantly in ironmaking processes. Assuming a coke consumption of 350 kg coke per tonne of hot metal and replacing it with 5% torrefied biomass injected as PC with an additional 100 m3/tHM biogas injection, the BF’s CO2 emission related to the coke can be lowered by 7.9% to 108 kg/tHM. In such a manner, the recovered slag heat can directly contribute to CO2-footprint reduction and improve the circular economy and metallurgical sustainability.