bluuebunny/crossref_metadata_2025 huggingface dataset:
Suppression of Chitin-Triggered Immunity by a New Fungal Chitin-Binding Effector Resulting from Alternative Splicing of a Chitin Deacetylase Gene
Authors: Martínez-Cruz Jesús M. , Polonio Álvaro , Ruiz-Jiménez Laura , Vielba-Fernández Alejandra , Hierrezuelo Jesús , Romero Diego , de Vicente Antonio , Fernández-Ortuño Dolores , Pérez-García Alejandro
Published: September 2022

Phytopathogenic fungi have evolved mechanisms to manipulate plant defences, such as chitin-triggered immunity, a plant defensive response based on the recognition of chitin oligomers by plant-specific receptors. To cope with chitin resistance, fungal pathogens have developed different strategies to prevent chitin recognition, such as binding, breaking, or modifying immunogenic oligomers. In powdery mildew fungi, the activity of chitin deacetylase (CDA) is crucial for this purpose, since silencing of the CDA gene leads to a rapid activation of chitin signalling and the subsequent suppression of fungal growth. In this work, we have identified an unusually short CDA transcript in Podosphaera xanthii, the cucurbit powdery mildew pathogen. This transcript, designated PxCDA3, appears to encode a truncated version of CDA resulting from an alternative splicing of the PxCDA gene, which lacked most of the chitin deacetylase activity domain but retained the carbohydrate-binding module. Experiments with the recombinant protein showed its ability to bind to chitin oligomers and prevent the activation of chitin signalling. Furthermore, the use of fluorescent fusion proteins allowed its localization in plant papillae at pathogen penetration sites. Our results suggest the occurrence of a new fungal chitin-binding effector, designated CHBE, involved in the manipulation of chitin-triggered immunity in powdery mildew fungi.
Overexpression of the White Opaque Switching Master Regulator Wor1 Alters Lipid Metabolism and Mitochondrial Function in Candida albicans
Authors: Hidalgo-Vico Susana , Casas Josefina , García Carolina , Lillo M. Pilar , Alonso-Monge Rebeca , Román Elvira , Pla Jesús
Published: September 2022

Candida albicans is a commensal yeast that inhabits the gastrointestinal tract of humans; increased colonization of this yeast in this niche has implicated the master regulator of the white-opaque transition, Wor1, by mechanisms not completely understood. We have addressed the role that this transcription factor has on commensalism by the characterization of strains overexpressing this gene. We show that WOR1 overexpression causes an alteration of the total lipid content of the fungal cell and significantly alters the composition of structural and reserve molecular species lipids as determined by lipidomic analysis. These cells are hypersensitive to membrane-disturbing agents such as SDS, have increased tolerance to azoles, an augmented number of peroxisomes, and increased phospholipase activity. WOR1 overexpression also decreases mitochondrial activity and results in altered susceptibility to certain oxidants. All together, these changes reflect drastic alterations in the cellular physiology that facilitate adaptation to the gastrointestinal tract environment.
Body Image and Body Mass Index Influence on Psychophysical Well-Being in Bariatric Patients: A Cross-Sectional Study
Authors: Campedelli Virginia , Ciacchella Chiara , Veneziani Giorgio , Meniconzi Irene , Paone Emanuela , Silecchia Gianfranco , Lai Carlo
Published: September 2022

Background: Psychophysical factors may have an impact on the disease of obesity, and it is important to explore which aspects may play an important role on the well-being of obese patients undergoing bariatric surgery. The purpose of this study was to assess the associations of a high body mass index (BMI) and greater dissatisfaction with body image with higher levels of psychopathological aspects, feelings of hopelessness, and psychological and physical health in patients undergoing evaluation for bariatric surgery. Methods: Fifty-nine patients undergoing bariatric surgery filled out the Symptom Checklist-90-Revised, the Body Uneasiness Test, the 12-item Short Form Survey, the Beck Inventory Scale II, and the Beck Hopelessness Scale. Correlations and hierarchical regressions between measures were performed. Results: Dissatisfaction with the perception of one’s own body image was strongly correlated with a worse psychophysiological health. On the contrary, BMI showed no significant correlation with the previous variables. Furthermore, the perception of one’s own body image significantly predicted the state of psychological health. Conclusions: The findings showed a more relevant role of body image compared to the BMI in the association with psychological outcomes, suggesting the importance of considering body image in the assessment and treatment of obese patients requiring bariatric treatment.
Status of ALS Treatment, Insights into Therapeutic Challenges and Dilemmas
Authors: Khamaysa Mohammed , Pradat Pierre-François
Published: September 2022

Amyotrophic lateral sclerosis (ALS) is an extremely heterogeneous disease of motor neurons that eventually leads to death. Despite impressive advances in understanding the genetic, molecular, and pathological mechanisms of the disease, the only drug approved to date by both the FDA and EMA is riluzole, with a modest effect on survival. In this opinion view paper, we will discuss how to address some challenges for drug development in ALS at the conceptual, technological, and methodological levels. In addition, socioeconomic and ethical issues related to the legitimate need of patients to benefit quickly from new treatments will also be addressed. In conclusion, this brief review takes a more optimistic view, given the recent approval of two new drugs in some countries and the development of targeted gene therapies.
Knowledge Collaboration among Tax Professionals through the Lens of a Community of Practice
Authors: Bahar Nurhidayah , Bahri Shamshul , Zakaria Zarina
Published: September 2022

This paper presents knowledge collaboration among tax professionals in a tax-knowledge context within Malaysian accounting associations through the conceptual lens of a community of practice. Semi-structured in-depth interviews were conducted with a total of 29 tax professionals. Additionally, data were also gathered from field notes and archival data. The findings revealed that the Malaysian accounting-professional associations reflected a community of practice. Knowledge collaboration occurs among members in this community in order to attain the highest standard of technical and professional competency in tax knowledge and practice. The findings from this study complement and expand previous research on CoP, knowledge management, and collaboration. The findings suggest exploring a better strategy to implement a central repository of knowledge acquired or generated by the members within the community to support the learning lifecycle.
Tests of Physicochemical and Mechanical Strength Properties of Polymer Composites on an Epoxy Resin Matrix, Modified by a Constant Magnetic Field
Authors: Miękoś Ewa , Cichomski Michał , Zieliński Marek , Klepka Tomasz , Sroczyński Dariusz , Fenyk Anna
Published: September 2022

The aim of the research presented in the paper was to obtain new polymer composites with strong functional properties on the Epidian 5 epoxy resin matrix. The polymer composites contained admixtures of expanded graphite, powder graphite, birch bark containing botulin, and yellow dextrin in set amounts of 20% by weight. Their various mechanical parameters and physicochemical properties were investigated. The research involved determining the effect of a constant magnetic field with magnetic induction B, under the influence of which the parameters and properties of polymer composites have been changed. For example, in a constant magnetic field with an induction of B = 0.5 T there was an increase in the hardness of the composite with an admixture of birch bark from 24.01 to 26.96 N/mm2 (12.3%), or in the composite with the addition of yellow dextrin from 26.12 to 29.93 N/mm2 (14.6%). It was also found, for example, that the water absorption of the resin itself decreased from 0.18% to 0.13%, and the composite with graphite powder from 0.48% to 0.46%. Changes in these parameters, often beneficial, may be important in terms of potential application of those new materials in industry as alternatives.
The Effect of the Operation of Downhole Equipment on the Processes of Corrosive Wear (by the Example Inflow Control Devices of Nozzle Type)
Authors: Kruk Pavel , Golubev Ivan , Shaposhnikov Nikita , Shinder Julia , Kotov Dmitry
Published: September 2022

Existing approaches to assessing the reliability and safe operation of downhole equipment provide for assessing only the direct impact of erosion and corrosion processes on the degradation of the material. At the same time, the influence of downhole equipment operating modes on the intensity of corrosion and erosion processes is not evaluated. The necessity of using inflow control devices is shown. The necessity of selecting inflow control devices for specific operating modes of the well is highlighted in order to avoid increased erosion wear due to increased sand production. In this article, a series of studies was conducted to assess the influence of the hydrodynamic characteristics of the fluid flow, which vary depending on the operating modes of the nozzle-type inflow control device, on corrosion processes in the well. It was shown that the level of wall shear stress (WSS) of the base pipe, immediately after the flow control device in the direction of fluid flow, affects the intensification of corrosion processes in downhole equipment. Studies of WSS on the pipe wall were carried out using a dynamic autoclave and elements of mathematical modeling. The design factors (the angle of inclination of the main hydraulic channel of the inflow control device relative to the base pipe) affecting the change in tangential stresses on the wall of the base pipe were investigated. The mechanism of corrosion wear of the base pipe was revealed.
Dispersion and Aggregation Fate of Individual and Co-Existing Metal Nanoparticles under Environmental Aqueous Suspension Conditions
Authors: Bathi Jejal Reddy , Roy Shuvashish , Tareq Syed , Potts Gretchen E. , Palchoudhury Soubantika , Sweck Samantha O. , Gadhamshetty Venkataramana
Published: September 2022

The use of diverse metal nanoparticles (MNPs) in a wide range of commercial products has led to their co-existence in the aqueous environment. The current study explores the dispersion and aggregation fate of five prominent MNPs (silver, copper, iron, nickel, and titanium), in both their individual and co-existing forms. We address a knowledge gap regarding their environmental fate under turbulent condition akin to flowing rivers. We present tandem analytical techniques based on dynamic light scattering, ultraviolet-visible spectroscopy, and inductively coupled plasma atomic emission spectroscopy for discerning their dispersion behavior under residence times of turbulence, ranging from 0.25 to 4 h. The MNPs displayed a multimodal trend for dispersion and aggregation behavior with suspension time in aqueous samples. The extent of dispersion was variable and depended upon intrinsic properties of MNPs. However, the co-existing MNPs displayed a dominant hetero-aggregation effect, independent of the residence times. Further research with use of real-world environmental samples can provide additional insights on the effects of sample chemistry on MNPs fate.
Study on the Stability of Bio-Oil Modified Prime Coat Oil Based on Molecular Dynamics
Authors: Shi Shuang , Lin Lanqin , Hu Zhaoguang , Gu Linhao , Zhang Yanning
Published: September 2022

To explore the effect of different emulsifier contents on the stability performance of biomass-emulsified asphalt, three types of emulsified asphalt with 1%, 3%, and 5% anionic emulsifiers were prepared and analyzed by molecular dynamics simulation and macroscopic experiments. Firstly, we used molecular simulation software (Material Studio, MS) to construct a model of biomass-emulsified asphalt with different emulsifier contents and analyzed the microscopic mechanism of the emulsifier to improve the stability of the emulsified asphalt by the radial distribution function, interaction energy, interfacial layer thickness, and solubility parameters of the emulsified asphalt system with different emulsifier contents. The results were validated by macro and micro tests including storage stability, particle size determination, and infrared spectroscopy. The results show that at low emulsifier contents, the emulsifier can reduce the interfacial tension between the oil–water interface and expand the transition region between the two phases (interfacial layer thickness), which will prevent interparticle agglomeration and reduce the emulsion particle size, thus reducing the settling rate and ensuring the stability of the emulsion. When the emulsifier content is further increased beyond the critical micelle concentration, the emulsifiers will agglomerate with each other and show larger peaks in the radial distribution function, and the phenomenon of emulsifier agglomeration will appear in the five-day storage stability test, resulting in a corresponding decrease in the proximity of the infrared absorption peak area ratio in the same wavelength band of the upper and lower layers of the biomass-emulsified asphalt, and the emulsion stability decreases instead.
Optimization of Tensile Strength and Young’s Modulus of CNT–CF/Epoxy Composites Using Response Surface Methodology (RSM)
Authors: Rahman Md. Rezaur , Taib Nur-Azzah Afifah Binti , Matin Mohammed Mahbubul , Rahman Mohammed Muzibur , Bakri Muhammad Khusairy Bin , Alexanrovich Taranenko Pavel , Vladimirovich Sinitsin Vladimir , Sanaullah Khairuddin , Tazeddinova Diana , Khan Afrasyab
Published: September 2022

Composites such as carbon fiber are used extensively by automotive, aerospace, marine, and energy industries due to their strong mechanical properties. However, there are still many areas it is lacking in testing, especially related to its electrophoretic deposition. In this research work, the tensile strength and Young’s modulus of CNT–CF/epoxy composites were measured using the tensile test by varying the electrophoretic deposition (EPD) process parameters. Response surface methodology (RSM) was used to optimize the three main parameters in this EPD process: the volume ratio (water as the basis), deposition voltage, and time to obtain the maximum tensile properties of the composites. There were four volume ratios (0%, 20%, 80% and 100%) used in this design of experiment (DoE) with ratios’ pairs of 0%, 100%, and 20%, 80%. For this study, water and methanol were used as the suspension medium. This design’s deposition voltage and time were 10 to 20 V and 5 to 15 min. ANOVA further verified the responses’ adequacy. The optimum conditions for the first Design of Experiment (DoE) (0% and 100%) were identified as a volume ratio of 99.99% water, deposition voltage of 10 V, and 12.14 min. These conditions provided the maximum strength of these composites with a tensile strength of 7.41 N/mm2 and Young’s modulus of 279.9 N/mm2. Subsequently, for the second DoE (20% and 80%), tensile strength of 7.28 N/mm2 and Young’s modulus of 274.1 N/mm2 were achieved with the ideal conditions: volume ratio of 44.80% water, deposition voltage of 10.04 V, and time of 6.89 min. It can be concluded that the ideal interaction between these three EPD parameters was necessary to achieve composites with good tensile properties.
Brillouin Scattering and First-Principles Studies of BaMO3 (M = Ti, Zr, and Cu) Perovskites
Authors: Helal Md Al , Kojima Seiji
Published: September 2022

Perovskite oxides with the general formula ABO3 comprise a large number of families among the structures of oxide-based materials, and currently, several perovskite structures have been identified. From a variety of compositions and structures, various functions are observed in perovskite compounds, and therefore, they became very useful for various applications in the electronic and medical industries. One of the most puzzling issues for perovskite compounds is the understanding of the vibration and relaxation dynamics in the gigahertz range. In that sense, the micro-Brillouin scattering system is a very effective tool to probe the gigahertz dynamics, and also, first-principles calculations can be used to describe the phonon structure with different atomic contributions. The micro-Brillouin scattering system and first-principles calculations provide the fundamental information on a variety of vibration and relaxation processes related to structural phase transitions under different external conditions such as temperature, electric field, and pressure. This review article summarizes the Brillouin scattering and first-principles studies on BaMO3 (M = Ti, Zr, and Cu). Through a detailed analysis of the existing results, we summarize the existing limitations and future perspectives in these research areas, which may propel the development of different perovskite ferroelectrics and extend their practical application areas.
Effect of Microstructure Refinement on the Corrosion Behavior of the Bioresorbable Mg-1Zn-0.2Ca and Mg-1Ca Alloys
Authors: Kulyasova Olga B. , Khudododova Ganjina D. , Dyakonov Grigory S. , Zheng Yufeng , Valiev Ruslan Z.
Published: September 2022

This paper presents a comprehensive study of the effect of the processing by high-pressure torsion (HPT) on the corrosion behavior in Ringer’s solution for two popular bioresorbable magnesium alloys—Mg-1Ca and Mg-1Zn-0.2Ca. Three states were studied for each alloy—the initial homogenized state, the as-HPT-processed state and the state after subsequent annealing at 250 and 300 °C. It is shown that HPT processing results in a very strong grain refinement in both alloys down to a mean grain size of about 210 nm for the Mg-1Ca alloy and 90 nm for the Mg-1Zn-0.2Ca alloy, but their corrosion resistance values differ significantly (by an order of magnitude). The conducted precision scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction studies demonstrate that such a difference in the corrosion behavior is conditioned by a difference in the morphology and origin of the nano-sized particles of second phases, as well as by a change in the electrochemical properties of the “particle–α-Mg” pair. The obtained results are discussed from the perspective of the innovative applications of biodegradable Mg alloys for the manufacture of advanced medical implants and products.
Coming New Age of Marine Glycomics: The Fundamental, Medical, and Ecological Aspects
Authors: Fujii Yuki , Gerdol Marco , Ozeki Yasuhiro
Published: September 2022

This Special Issue “Marine Glycomics” (https://www.mdpi.com/journal/marinedrugs/special_issues/Marine_Glycomics, accessed on 12 September 2022) provided new approachesand information on bioactive compounds, such as glycans and lectins from marine animals,seaweeds, and microorganisms for the application of clinical therapy and elucidation of thephysiological functions of marine organisms [...]
Caspase-1 and Cathepsin B Inhibitors from Marine Invertebrates, Aiming at a Reduction in Neuroinflammation
Authors: Moreno Rafaela Indalecio , Zambelli Vanessa O. , Picolo Gisele , Cury Yara , Morandini André C. , Marques Antonio Carlos , Sciani Juliana Mozer
Published: September 2022

Neuroinflammation is a condition associated with several types of dementia, such as Alzheimer’s disease (AD), mainly caused by an inflammatory response to amyloid peptides that induce microglial activation, with subsequent cytokine release. Neuronal caspase-1 from inflammasome and cathepsin B are key enzymes mediating neuroinflammation in AD, therefore, revealing new molecules to modulate these enzymes may be an interesting approach to treat neurodegenerative diseases. In this study, we searched for new caspase-1 and cathepsin B inhibitors from five species of Brazilian marine invertebrates (four cnidarians and one echinoderm). The results show that the extract of the box jellyfish Chiropsalmus quadrumanus inhibits caspase-1. This extract was fractionated, and the products monitored for their inhibitory activity, until the obtention of a pure molecule, which was identified as trigonelline by mass spectrometry. Moreover, four extracts inhibit cathepsin B, and Exaiptasia diaphana was selected for subsequent fractionation and characterization, resulting in the identification of betaine as being responsible for the inhibitory action. Both molecules are already found in marine organisms, however, this is the first study showing a potent inhibitory effect on caspase-1 and cathepsin B activities. Therefore, these new prototypes can be considered for the enzyme inhibition and subsequent control of the neuroinflammation.
Direct Observation of the Deformation Mechanism of Twin-Structured Ni NWs under Bending Strain
Authors: Zhang Zihao , Yang Chengpeng , Guo Yizhong , Li Xueqiao , Kong Deli , Lu Yan , Nie Changjiang , Wang Lihua
Published: September 2022

In situ atomic-scale bending tests of twin-structured Ni nanowires were realised using a homemade deformation device. The results showed that the plastic deformation mechanism in twin-structured Ni nanowires depended on the deformation stage. At the early stages of bending deformation, the plasticity of twin-structured Ni nanowires was controlled by dislocations interacting with the twin boundaries or parallel to them. With increasing bending strain, both dislocation and face-centred cubic–body-centred tetragonal phase transition occurred. At very high bending strain, grain boundaries resulting from the lattice distortion/collapse were formed. This study details the deformation mechanisms of the twin-structured Ni nanowires under bending deformation, which advances the basic understanding of the plasticity mechanisms in metals.
Working Mechanisms and Experimental Research of Piezoelectric Pump with a Cardiac Valve-like Structure
Authors: Zhou Jiayue , Sun Wanting , Fu Jun , Liu Huixia , Wang Hongmei , Yan Qiufeng
Published: September 2022

In this study, based on the working principle of the cardiac valve structure that prevents blood from flowing back, a piezoelectric pump with a cardiac valve-like structure (PPCVLS) is designed. The operating principles of cardiac-valve-like structures (CVLSs) are introduced. Furthermore, the closure conditions of the CVLSs on both sides of the flow channel are explored. The principle behind the working-state conversion between “valve-based” and “valve-less” of PPCVLS is also analyzed. A high-speed dynamic microscopic image-analysis system was utilized to observe and verify the working-state conversion between “valve-based” and “valve-less” PPCVLSs. The resonant frequency of the piezoelectric pump was measured by Doppler laser vibrometer, and the optimal working frequency of the piezoelectric vibrator was determined as 22.35 Hz. The prototype piezoelectric pump was fabricated by the 3D printing technique, and the output performance of the piezoelectric pump was also evaluated. The experimental results show that the piezoelectric pump is valve-based when the driving voltage is greater than 140V, and the piezoelectric pump is valve-less when the driving voltage is less than 140 V. Furthermore, the maximum output pressure of the piezoelectric pump was 199 mm H2O when driven by the applied voltage of 220 V at 7 Hz, while the maximum flow rate of the piezoelectric pump was 44.5 mL/min when driven by the applied voltage of 220 V at 11 Hz.
Characterization of a Droplet Containing the Clustered Magnetic Beads Manipulation by Magnetically Actuated Chips
Authors: Yen Sheng-Huang , Chin Pei-Chieh , Hsu Jun-Yu , Lin Jr-Lung
Published: September 2022

A magnetically actuated chip was successfully developed in this study to perform the purpose of transportation for a droplet containing clustered magnetic beads. The magnetic field gradient is generated by the chip of the two-layer 4 × 4 array micro-coils, which was commercially fabricated by printing circuit board (PCB) technology. A numerical model was first established to investigate the magnetic field and thermal field for such a micro-coil. Consequently, the numerical simulations were in reasonable agreement with the experimental results. Moreover, a theoretical analysis was derived to predict the dynamic behaviors of the droplets. This analysis will offer the optimal operation for such a magnetically actuated chip. This study aims to successfully implement the concept of “digital microfluidics” in “point-of-care testing” (POCT). In the future, the micro-coil chip will be of substantial benefit to genetic analysis and infectious disease detection.
Low-Cost In Vivo Full-Range Optical Coherence Tomography Using a Voice Coil Motor
Authors: Liao Xiaoqiao , He Liang , Duan Zhao , Tian Peng , He Yu , Deng Qinyuan , Ma Zeyu , Song Ruiqi , Wu Leixin
Published: September 2022

In this work, we demonstrated a novel and low-cost full-range optical coherence tomography (FROCT) method. In comparison with the off-pivot approach, which needs precise control of the deflecting distance and should be adjusted for different situations, our proposed method is more flexible without regulating the system itself. Different from the previous systems reported in the literature, which used a high-cost piezo-driven stage to introduce the phase modulation, our system utilizes a cost-effective voice coil motor for retrieving the complex-valued spectral signal. The complex-valued data, with a twofold increase in the accessible depth range, can be calculated using an algorithm based on the Hilbert transform and Dirac delta function. To confirm the effectivity of our method, both simulation and experiments were performed. In particular, for the in vivo experiment, we presented the FROCT result of a fingernail fold, demonstrating the availability of in vivo imaging. Since the key element of our system is a low-cost voice coil motor, which is flexible and more accessible for most of the clinics, we believe that it has great potential to be a clinical modality in the future.
An Analytic Model of Transient Heat Conduction for Bi-Layered Flexible Electronic Heaters by Symplectic Superposition
Authors: Xu Dian , Xiong Sijun , Meng Fanxing , Wang Bo , Li Rui
Published: September 2022

In a flexible electronic heater (FEH), periodic metal wires are often encapsulated into the soft elastic substrate as heat sources. It is of great significance to develop analytic models on transient heat conduction of such an FEH in order to provide a rapid analysis and preliminary designs based on a rapid parameter analysis. In this study, an analytic model of transient heat conduction for bi-layered FEHs is proposed, which is solved by a novel symplectic superposition method (SSM). In the Laplace transform domain, the Hamiltonian system-based governing equation for transient heat conduction is introduced, and the mathematical techniques incorporating the separation of variables and symplectic eigen expansion are manipulated to yield the temperature solutions of two subproblems, which is followed by superposition for the temperature solution of the general problem. The Laplace inversion gives the eventual temperature solution in the time domain. Comprehensive time-dependent temperatures by the SSM are presented in tables and figures for benchmark use, which agree well with their counterparts by the finite element method. A parameter analysis on the influence of the thermal conductivity ratio is also studied. The exceptional merit of the SSM is on a direct rigorous derivation without any assumption/predetermination of solution forms, and thus, the method may be extended to more heat conduction problems of FEHs with more complex structures.
Structural Optimization and MEMS Implementation of the NV Center Phonon Piezoelectric Device
Authors: Shen Xiang , Zhao Liye , Ge Fei
Published: September 2022

The nitrogen-vacancy (NV) center of the diamond has attracted widespread attention because of its high sensitivity in quantum precision measurement. The phonon piezoelectric device of the NV center is designed on the basis of the phonon-coupled regulation mechanism. The propagation characteristics and acoustic wave excitation modes of the phonon piezoelectric device are analyzed. In order to improve the performance of phonon-coupled manipulation, the influence of the structural parameters of the diamond substrate and the ZnO piezoelectric layer on the phonon propagation characteristics are analyzed. The structure of the phonon piezoelectric device of the NV center is optimized, and its Micro-Electro-Mechanical System (MEMS) implementation and characterization are carried out. Research results show that the phonon resonance manipulation method can effectively increase the NV center’s spin transition probability using the MEMS phonon piezoelectric device prepared in this paper, improving the quantum spin manipulation efficiency.
In Situ U–Th–Pb Dating of Parisite: Implication for the Age of Mineralization of Colombian Emeralds
Authors: Altenberger Uwe , Rojas-Agramonte Yamirka , Yang Yueheng , Fernández-Lamus Jimmy , Häger Tobias , Guenter Christina , Gonzalez-Pinzón Alejandra , Charris-Leal Felipe , Artel Julia
Published: September 2022

Parisite-Ce (Ca(Ce,La)2(CO3)3F2) is a rare-earth (REE) fluorocarbonate mineral first described from the world-famous emerald mines of the Muzo district, Boyacá Province, Colombia. Four samples of parisite-Ce collected from outcrops near Muzo have been geochemically studied and dated using the in situ laser ablation U–Th–Pb method. Our study shows that the REE abundance of parisite is controlled by the leaching of the wall rocks (black schist). Furthermore, we show that the parisite-Ce crystals formed in textural equilibrium with the emeralds, suggesting a similar time of crystallization. Our analysis demonstrates the capability of parisite as a geochronometer and shows that precise and accurate U–Th–Pb ages can be obtained from parisite after common 207Pb correction. A higher precision date was obtained with the Th–Pb ratio rather than with the U–Pb ratio because of the relatively higher content of Th than U in the samples. The samples yielded 208Th–232Pb ages ranging from ~47 to 51 Ma. The new ages are ~10 Ma older than previously reported Ar–Ar ages and ~10 Ma younger than previously reported Rb/Sr ages. These results will have significant implications for understanding the timing of mineralization and crystallization of emerald deposits in Colombia. Furthermore, this study opens new avenues for dating similar deposits worldwide.
Coastal Environment Impact on the Construction Materials of Anfushi’s Necropolis (Pharos’s Island) in Alexandria, Egypt
Authors: Fahmy Abdelrhman , Molina-Piernas Eduardo , Martínez-López Javier , Machev Philip , Domínguez-Bella Salvador
Published: September 2022

The only example and reference of Ptolemaic Alexandrian tombs, with clear integrations of Egyptian-style scenes and decorations, is considered an endangered archaeological site due to different coastal environmental risks in Alexandria and the absence of maintenance. Anfushi’s Necropolis is located near the western harbour (Island of Pharos) and dates back to the 2nd century BC. Sea level rises, earthquakes, flooding, storminess, variations in temperature, rainfall, and wind are the factors that have the largest effect on the destruction and decay of Anfushi’s Necropolis building materials. This paper’s main objectives were to characterize this necropolis’s building materials and assess its durability problems and risks regarding the coastal environment. Additionally, the vector mapping of its architectural and structural elements was applied for documentation and recording purposes for the necropolis. To achieve these aims, field (recording and photographs), desk (engineering drawing and mapping), and laboratory works (X-ray diffraction, X-ray fluorescence, binocular microscopy, polarizing microscopy, and scanning electron microscopy) were carried out. The results confirmed the probabilistic risk of sea level rises and its impact on the submergence of Anfushi’s Necropolis. The structural deficiencies of the tombs were caused by the effect of earthquake tremors along with anthropogenic factors. In addition, chemical and microscopic investigations showed that salt weathering (halite and gypsum) induced the decay of the building materials.
First High-Power CSEM Field Test in Saudi Arabia
Authors: Ashadi Abdul , Martinez Yardenia , Kirmizakis Panagiotis , Hanstein Tilman , Xu Xiayu , Khogali Abid , Paembonan Andri , AlShaibani Ahmed , Al-Karnos Assem , Smirnov Maxim , Strack Kurt , Soupios Pantelis
Published: September 2022

We conducted an initial high-power CSEM (controlled-source electromagnetic method) survey in a coastal salt-flat area in the broader area of Half Moon Bay, in the southern part of Dammam Peninsula in the eastern province of Saudi Arabia. The primary purpose of this work was to verify the technology, but we were also able to detect and characterize potential economic brines in the study area. For a high-quality data acquisition, several transmitter–receiver configurations, different acquisition parameters, and passive and active EM data were collected, evaluated, processed, and interpreted to characterize the subsurface. The long-offset EM (LOTEM) and the focused-source EM (FSEM) were the optimum configurations due to the high-quality of the collected data. This is a starting point for using the CSEM method towards the O&G, geothermal, CO2 sequestration, groundwater, lithium brine, and other natural resources’ exploration and exploitation in the Gulf countries.
A High-Temperature Thermal Simulation Experiment for Coal Graphitization with the Addition of SiO2
Authors: Chen Gaojian , Cao Daiyong , Wang Anmin , Wei Yingchun , Liu Zhifei , Zhao Meng
Published: September 2022

The effect of SiO2 on coal graphitization was investigated by adding SiO2 as an additive to vitrinite in coal from the Gemudi mining area in Guizhou province (SW China) via a high-temperature heating treatment. The graphitization products of the samples were analyzed by X-ray diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM), and the influence of the SiO2 additive on the process of coal graphitization was investigated. The results showed that, with the temperature increases, the graphitization degree of all samples was promoted, and the orderliness of the microcrystalline structure in the vitrinite increased. Compared with the samples without additives, the graphitization degree, graphite lamellae ductility, and stacking degree of the samples with SiO2 additives were higher, and the carbon layer spacing reached 0.3379 nm at 3000 °C, entering the graphite stage. The Raman spectra showed that the peak intensities of the defect structures (D1 and D2) in the samples with SiO2 were lower than those of the samples without additives, exhibiting fewer in-plane and interlayer defects in the samples with SiO2. The microstructures of the experimental samples were observed by HRTEM; at the same temperature, the carbon layer stacking degree of the samples with the SiO2 additives was higher than that of the samples without SiO2, and large graphite lamellae with smoother and clearer edges were observed.
Functionalized Controlled Porous Glasses for Producing Radical-Free Hyperpolarized Liquids by Overhauser DNP
Authors: Kircher Raphael , Mross Sarah , Hasse Hans , Münnemann Kerstin
Published: September 2022

Overhauser dynamic nuclear polarization (ODNP) can be used as a tool for NMR signal enhancement and happens on very short time scales. Therefore, ODNP is well suited for the measurement of fast-flowing samples, even in compact magnets, which is beneficial for the real-time monitoring of chemical reactions or processes. ODNP requires the presence of unpaired electrons in the sample, which is usually accomplished by the addition of stable radicals. However, radicals affect the nuclear relaxation times and can hamper the NMR detection. This is circumvented by immobilizing radicals in a packed bed allowing for the measurement of radical-free samples when using ex situ DNP techniques (DNP build-up and NMR detection happen at different places) and flow-induced separation of the hyperpolarized liquid from the radicals. Therefore, the synthesis of robust and chemically inert immobilized radical matrices is mandatory. In the present work, this is accomplished by immobilizing the radical glycidyloxy-tetramethylpiperidinyloxyl with a polyethyleneimine (PEI) linker on the surface of controlled porous glasses (CPG). Both the porosity of the CPGs and also the size of the PEI-linker were varied, resulting in a set of distinct radical matrices for continuous-flow ODNP. The study shows that CPGs with PEI-linkers provide robust, inert and efficient ODNP matrices.
Structural Insight of KSIII (β-Ketoacyl-ACP Synthase)-like Acyltransferase ChlB3 in the Biosynthesis of Chlorothricin
Authors: Saeed Asad Ullah , Rahman Mueed Ur , Chen Hai-Feng , Zheng Jianting
Published: September 2022

Chlorothricin (CHL) belongs to a spirotetronate antibiotic family produced by Streptomyces antibioticus that inhibits pyruvate carboxylase and malate dehydrogenase. For the biosynthesis of CHL, ChlB3 plays a crucial role by introducing the 6-methylsalicylic acid (6MSA) moiety to ChlB2, an acyl carrier protein (ACP). However, the structural insight and catalytic mechanism of ChlB3 was unclear. In the current study, the crystal structure of ChlB3 was solved at 3.1 Å-resolution and a catalytic mechanism was proposed on the basis of conserved residues of structurally related enzymes. ChlB3 is a dimer having the same active sites as CerJ (a structural homologous enzyme) and uses a KSIII-like fold to work as an acyltransferase. The relaxed substrate specificity of ChlB3 was defined by its catalytic efficiencies (kcat/Km) for non-ACP tethered synthetic substrates such as 6MSA-SNAC, acetyl-SNAC, and cyclohexonyl-SNAC. ChlB3 successfully detached the 6MSA moiety from 6MSA-SNAC substrate and this hydrolytic activity demonstrated that ChlB3 has the potential to catalyze non-ACP tethered substrates. Structural comparison indicated that ChlB3 belongs to FabH family and showed 0.6–2.5 Å root mean square deviation (RMSD) with structural homologous enzymes. Molecular docking and dynamics simulations were implemented to understand substrate active site and structural behavior such as the open and closed conformation of the ChlB3 protein. The resultant catalytic and substrate recognition mechanism suggested that ChlB3 has the potential to use non-native substrates and minimize the labor of expressing ACP protein. This versatile acyltransferase activity may pave the way for manufacturing CHL variants and may help to hydrolyze several thioester-based compounds.
Polygonum capitatum, the Hmong Medicinal Flora: A Comprehensive Review of Its Phytochemical, Pharmacological and Pharmacokinetic Characteristics
Authors: Lin Yan , He Lei , Chen Xing-Jun , Zhang Xu , Yan Xue-Long , Tu Bo , Zeng Zhu , He Ming-Hui
Published: September 2022

Polygonum capitatum, known as “Tou Hua Liao” (Chinese name), is a crucial source of Hmong medicinal plants that has benefited human health for a long time. This folk-medicinal plant is widely distributed in the south-west of China for the treatment of various urologic disorders including urinary tract infections, pyelonephritis, and urinary calculus. The purpose of this paper was to provide a systematic and comprehensive overview of the traditional usages, botany, phytochemistry, pharmacology, pharmacokinetics and clinical applications of this flora. Up until the end of 2022, at least 91 compounds had been reported from P. capitatum, mainly covering the classes of flavonoids, lignanoids, phenols and other components. The compounds and extracts isolated from P. capitatum exhibit a wide range of pharmacological activities, such as anti-inflammatory, antioxidant, antimicrobial, anticancer, analgesic, hypothermic, diuretic and other pharmacological effects. Qualitative and quantitative chemical analyses were also covered. Furthermore, the possible development trends and perspectives for future research on this medicinal plant were also discussed.
The Conversion of Superoxide to Hydroperoxide on Cobalt(III) Depends on the Structural and Electronic Properties of Azole-Based Chelating Ligands
Authors: Nishiura Toshiki , Ohta Takehiro , Ogura Takashi , Nakazawa Jun , Okamura Masaya , Hikichi Shiro
Published: September 2022

Conversion from superoxide (O2−) to hydroperoxide (OOH−) on the metal center of oxygenases and oxidases is recognized to be a key step to generating an active species for substrate oxidation. In this study, reactivity of cobalt(III)-superoxido complexes supported by facially-capping tridentate tris(3,5-dimethyl-4-X-pyrazolyl)hydroborate ([HB(pzMe2,X)3]−; TpMe2,X) and bidentate bis(1-methyl-imidazolyl)methylborate ([B(ImN-Me)2Me(Y)]−; LY) ligands toward H-atom donating reagent (2-hydroxy-2-azaadamantane; AZADOL) has been explored. The oxygenation of the cobalt(II) precursors give the corresponding cobalt(III)-superoxido complexes, and the following reaction with AZADOL yield the hydroperoxido species as has been characterized by spectroscopy (UV-vis, resonance Raman, EPR). The reaction of the cobalt(III)-superoxido species and a reducing reagent ([CoII(C5H5)2]; cobaltocene) with proton (trifluoroacetic acid; TFA) also yields the corresponding cobalt(III)-hydroperoxido species. Kinetic analyses of the formation rates of the cobalt(III)-hydroperoxido complexes reveal that second-order rate constants depend on the structural and electronic properties of the cobalt-supporting chelating ligands. An electron-withdrawing ligand opposite to the superoxide accelerates the hydrogen atom transfer (HAT) reaction from AZADOL due to an increase in the electrophilicity of the superoxide ligand. Shielding the cobalt center by the alkyl group on the boron center of bis(imidazolyl)borate ligands hinders the approaching of AZADOL to the superoxide, although the steric effect is insignificant.
Polyphenol-Rich Ginger (Zingiber officinale) for Iron Deficiency Anaemia and Other Clinical Entities Associated with Altered Iron Metabolism
Authors: Ooi Soo Liang , Pak Sok Cheon , Campbell Ron , Manoharan Arumugam
Published: September 2022

Ginger (Zingiber officinale) is rich in natural polyphenols and may potentially complement oral iron therapy in treating and preventing iron deficiency anaemia (IDA). This narrative review explores the benefits of ginger for IDA and other clinical entities associated with altered iron metabolism. Through in vivo, in vitro, and limited human studies, ginger supplementation was shown to enhance iron absorption and thus increase oral iron therapy’s efficacy. It also reduces oxidative stress and inflammation and thus protects against excess free iron. Ginger’s bioactive polyphenols are prebiotics to the gut microbiota, promoting gut health and reducing the unwanted side effects of iron tablets. Moreover, ginger polyphenols can enhance the effectiveness of erythropoiesis. In the case of iron overload due to comorbidities from chronic inflammatory disorders, ginger can potentially reverse the adverse impacts and restore iron balance. Ginger can also be used to synthesise nanoparticles sustainably to develop newer and more effective oral iron products and functional ingredients for IDA treatment and prevention. Further research is still needed to explore the applications of ginger polyphenols in iron balance and anaemic conditions. Specifically, long-term, well-designed, controlled trials are required to validate the effectiveness of ginger as an adjuvant treatment for IDA.
Production, Biochemical Characterization, and Kinetic/Thermodynamic Study of Inulinase from Aspergillus terreus URM4658
Authors: de Oliveira Rodrigo Lira , da Silva Suzana Pedroza , Converti Attilio , Porto Tatiana Souza
Published: September 2022

Inulinases are enzymes involved in the hydrolysis of inulin, which can be used in the food industry to produce high-fructose syrups and fructo-oligosaccharides. For this purpose, different Aspergillus strains and substrates were tested for inulinase production by solid-state fermentation, among which Aspergillus terreus URM4658 grown on wheat bran showed the highest activity (15.08 U mL−1). The inulinase produced by this strain exhibited optimum activity at 60 °C and pH 4.0. A detailed kinetic/thermodynamic study was performed on the inulin hydrolysis reaction and enzyme thermal inactivation. Inulinase was shown to have a high affinity for substrate evidenced by very-low Michaelis constant values (0.78–2.02 mM), which together with a low activation energy (19.59 kJ mol−1), indicates good enzyme catalytic potential. Moreover, its long half-life (t1/2 = 519.86 min) and very high D-value (1726.94 min) at 60 °C suggested great thermostability, which was confirmed by the thermodynamic parameters of its thermal denaturation, namely the activation energy of thermal denaturation (E*d = 182.18 kJ mol−1) and Gibbs free energy (106.18 ≤ ΔG*d ≤ 111.56 kJ mol−1). These results indicate that A. terreus URM4658 inulinase is a promising and efficient biocatalyst, which could be fruitfully exploited in long-term industrial applications.
Improvement in Optoelectronic Properties of Bismuth Sulphide Thin Films by Chromium Incorporation at the Orthorhombic Crystal Lattice for Photovoltaic Applications
Authors: Fazal Tanzeela , Iqbal Shahid , Shah Mazloom , Ismail Bushra , Shaheen Nusrat , Alrbyawi Hamad , Al-Anazy Murefah Mana , Elkaeed Eslam B. , Somaily H. H. , Pashameah Rami Adel , Alzahrani Eman , Farouk Abd-ElAziem
Published: September 2022

By using the chemical bath deposition approach, binary bismuth sulphides (Bi2S3) and chromium-doped ternary bismuth sulphides (Bi2−xCrxS3) thin films were effectively produced, and their potential for photovoltaic applications was examined. Structural elucidation revealed that Bi2S3 deposited by this simple and cost-effective method retained its orthorhombic crystal lattice by doping up to 3 at.%. The morphological analysis confirmed the crack-free deposition, hence making them suitable for solar cell applications. Optical analysis showed that deposited thin films have a bandgap in the range of 1.30 to 1.17 eV, values of refractive index (n) from 2.9 to 1.3, and an extinction coefficient (k) from 1.03 to 0.3. From the Hall measurements, it followed that the dominant carriers in all doped and undoped samples are electrons, and the carrier density in doped samples is almost two orders of magnitude larger than in Bi2S3. Hence, this suggests that doping is an effective tool to improve the optoelectronic behavior of Bi2S3 thin films by engineering the compositional, structural, and morphological properties.