bluuebunny/crossref_metadata_2025 huggingface dataset:
Semi-Scavenging Poultry as Carriers of Avian Influenza Genes
Authors: Badruzzaman A T M , Rahman Md. Masudur , Hasan Mahmudul , Hossain Mohammed Kawser , Husna Asmaul , Hossain Ferdaus Mohd Altaf , Giasuddin Mohammed , Uddin Md Jamal , Islam Mohammad Rafiqul , Alam Jahangir , Eo Seong-Kug , Fasina Folorunso Oludayo , Ashour Hossam M.
Published: February 2022

Ducks are the natural reservoir of influenza A virus and the central host for the avian influenza virus (AIV) subtype H5N1, which is highly pathogenic. Semi-scavenging domestic ducks allow for the reemergence of new influenza subtypes which could be transmitted to humans. We collected 844 cloacal swabs from semi-scavenging ducks inhabiting seven migratory bird sanctuaries of Bangladesh for the molecular detection of avian influenza genes. We detected the matrix gene (M gene) using real-time RT–PCR (RT–qPCR). Subtyping of the AIV-positive samples was performed by RT–qPCR specific for H5, H7, and H9 genes. Out of 844 samples, 21 (2.488%) were positive for AIV. Subtyping of AIV positive samples (n = 21) revealed that nine samples (42.85%) were positive for the H9 subtype, five (23.80%) were positive for H5, and seven (33.33%) were negative for the three genes (H5, H7, and H9). We detected the same genes after propagating the virus in embryonated chicken eggs from positive samples. Semi-scavenging ducks could act as carriers of pathogenic AIV, including the less pathogenic H9 subtype. This can enhance the pathogenicity of the virus in ducks by reassortment. The large dataset presented in our study from seven areas should trigger further studies on AIV prevalence and ecology.
Investigation of Euphorbia nivulia-HAM for Enzyme Inhibition Potential in Relation to the Phenolic and Flavonoid Contents and Radical Scavenging Activity
Authors: Younus Muhammad , Mohtasheem-ul-Hasan Muhammad , Ijaz Shakeel , Kamran Muhammad , Maqsood Ambreen , Saddique Bushra , Nisar Uzair , Ashraf Muhammad , Mahmoud Eman , El-Sabrout Ahmed , Elansary Hosam
Published: February 2022

Euphorbia nivulia-Ham (EN) is a neglected medicinal plant traditionally used for a number of pathologies, but it has not been explored scientifically. In the current study, its various fractions were assessed for their phenolic and flavonoid content, radical scavenging, as well as its enzyme inhibitory potential. The hydro-alcoholic crude extract (ENCr) was subjected to a fractionation scheme to obtain different fractions, namely n-hexane (ENHF), chloroform (ENCF), n-butanol (ENBF), and aqueous fraction (ENAF). The obtained results revealed that the highest phenolic and flavonoid content, maximum radical scavenging potential (91 ± 0.55%), urease inhibition (54.36 ± 1.47%), and α-glucosidase inhibition (97.84 ± 1.87%) were exhibited by ENCr, while the ENBF fraction exhibited the highest acetylcholinestrase inhibition (57.32 ± 0.43%). Contrary to these, hydro-alcoholic crude as well as the other fractions showed no significant butyrylcholinestrases (BChE) and carbonic anhydrase inhibition activity. Conclusively, it was found that EN possesses a significant radical scavenging and enzyme inhibitory potential. Thus, the study may be regarded a step forward towards evidence-based phyto-medicine.
(De)Activation (Ir)Reversibly or Degradation: Dynamics of Post-Translational Protein Modifications in Plants
Authors: Muleya Victor , Lois L. Maria , Chahtane Hicham , Thomas Ludivine , Chiapello Marco , Marondedze Claudius
Published: February 2022

The increasing dynamic functions of post-translational modifications (PTMs) within protein molecules present outstanding challenges for plant biology even at this present day. Protein PTMs are among the first and fastest plant responses to changes in the environment, indicating that the mechanisms and dynamics of PTMs are an essential area of plant biology. Besides being key players in signaling, PTMs play vital roles in gene expression, gene, and protein localization, protein stability and interactions, as well as enzyme kinetics. In this review, we take a broader but concise approach to capture the current state of events in the field of plant PTMs. We discuss protein modifications including citrullination, glycosylation, phosphorylation, oxidation and disulfide bridges, N-terminal, SUMOylation, and ubiquitination. Further, we outline the complexity of studying PTMs in relation to compartmentalization and function. We conclude by challenging the proteomics community to engage in holistic approaches towards identification and characterizing multiple PTMs on the same protein, their interaction, and mechanism of regulation to bring a deeper understanding of protein function and regulation in plants.
Hydrogen Generation by Hydrolysis of MgH2-LiH Composite
Authors: Wu Xiaojuan , Xue Huaqing , Peng Yong , Deng Jifeng , Xie Zewei , Zheng Jie , Li Xingguo , Li Shuan
Published: February 2022

As a most promising material for hydrogen generation by hydrolysis, magnesium hydride (MgH2) is also trapped by its yielded byproduct Mg(OH)2 whose dense passivated layers prevent the further contact of intimal MgH2 with water. In this work, LiH, as a destroyer, has been added to promote the hydrogen properties of MgH2. The results demonstrate that even 3 wt % LiH was added into MgH2-G, the hydrogen generation yield can increase about 72% compared to the hydrogen generation yield of MgH2-G. The possible mechanism is that Mg2+ from the hydrolysis of MgH2 preferentially bound with OH− ions from the hydrolysis of LiH to form Mg(OH)2 precipitation, which is dispersed in water rather than coated on the surface of MgH2. Moreover, adding MgCl2 into hydrolysis solution, using ball milling technology, and increasing the hydrolysis temperature can make the hydrolysis rate higher and reaction process more complete. It is noted that a too high weight ratio of LiH with too high of a hydrolysis temperature will make the reaction too violent to be safe in the experiment. We determinate the best experimental condition is that the LiH ratio added into MgH2 is 3 wt %, the hydrolysis temperature is 60 °C, and the concentration of MgCl2 hydrating solution is 1 M. MgH2-LiH composite hydrogen generation technology can meet the needs of various types of hydrogen supply and has broad application prospects.
Synthesis and Characterization of Imidazolium-Based Ionic Liquids and Evaluating Their Performance as Asphaltene Dispersants
Authors: Ghanem Alaa , Alharthy Rima D. , Desouky Saad M. , El-Nagar Raghda A.
Published: February 2022

With the projected increase in the production of heavy oil due to the energy crisis, asphaltene-related issues are likely to come to the forefront. This leads to operational problems, safety hazards, and oil production deficiencies, resulting in huge economic losses for the petroleum industry. Therefore, in this work, we aimed to inhibit asphaltene precipitation using ionic liquid (IL) compounds. ILs with long alkyl chains can inhibit the precipitation of asphaltene molecules due to the π–π* interactions between them and the formation of hydrogen bonds. A series of imidazolium-based ionic liquids, IL-0, IL-4, IL-10, and IL-16, were synthesized with yield percents of 79, 81, 80, and 83%, respectively. The prepared materials were characterized well using FTIR, 1H-NMR, and Elemental Analysis. The surface tension, interfacial tension (IFT), and different surface parameters were investigated at different temperatures to simulate the reservoir temperature. IL-0, IL-4, IL-10, and IL-16 displayed their γcmc values at 35, 34, 31, and 32 mN/m at 303 °K, respectively. It was found that the prepared ILs are good surfactants with low values of interfacial tension. Quantum structure–activity relationships using Density Functional Theory (DFT) were used to investigate the geometry optimization electronic structures, the energy gap (ΔE), and the reactivity of the cations of the prepared ILs. The synthesized ILs were evaluated as asphaltene dispersants using two different techniques. The viscometric technique showed that the asphaltene onset precipitation was 28.5 vol.%. This percent was postponed to 42.8, 50, 78.5, and 64.3 vol.%, after adding IL-0, IL-4, IL-10, and IL-16, respectively, and the spectroscopic technique confirmed the results.
Multi-Parameter Characteristics of Electric Arc Furnace Melting
Authors: Moskal Michał , Migas Piotr , Karbowniczek Mirosław
Published: February 2022

The article presents the results of analyses of numerical modelling of selected factors in electric arc furnace melts. The aim of the study was to optimise the melting process in an electric arc furnace using statistical-thermodynamic modelling based on, among other things, multiple linear regression (MLR). The article presents tools and methods which make it possible to identify the most significant indicators of the process carried out on the analysed unit from the point of view of improvement. The article presents the characteristics of the process and creation of the MLR model and, by applying its numerical analyses and results of calculations and simulations for selected variables and indicator, identifying the operation of a selected furnace. Developed model to demand of electric energy identification was used for calculations of energy balances, the distribution of the energy used in the furnace was presented.
Comparative Study on Biodegradation of Pure Iron Prepared by Microwave Sintering and Laser Melting
Authors: Zhao Yingchao , Feng Jun , Yu Hui , Lin Wangyang , Li Xin , Tian Yan , Zhao Mingchun
Published: February 2022

For biodegradable pure iron implants, a higher biodegradation rate is preferred. In this work, we compared the biodegradation of pure iron prepared by microwave sintering and laser melting (designated as MSed Fe and LMed Fe, respectively). The MSed Fe presented a distinct porous structure, while the LMed Fe presented a relatively compact structure without any obvious pores. The biodegradation rate of the MSed Fe was higher than that of the LMed Fe, and their biodegradation rates were higher than that of the as-cast Fe. The biodegradation rates of the MSed Fe and the LMed Fe were approximately 44 and 13 times higher than that of the as cast Fe, respectively. The biodegradation was closely related to the microstructure’s compactness and grain size. Moreover, the MSed Fe and the LMed Fe had satisfactory biocompatibility.
Cementitious Composites Reinforced with Waste Fibres from the Production of High-Quality Construction Textiles
Authors: Baričević Ana , Didulica Katarina , Frančić Smrkić Marina , Jelčić Rukavina Marija
Published: February 2022

In general, 20–25% of the original fibre weight is considered waste in the production of high-quality textiles for the construction sector. A market analysis has shown that in the Republic of Croatia alone, up to 327 tonnes of this waste is produced annually, which is enough to reinforce 50 to 150 thousand m3 of cementitious composites. This preliminary study aims to evaluate the contribution of glass, basalt and carbon fibres generated as waste in the local production of high-performance technical textiles, to the fresh and hardened properties of fibre reinforced mortars. In order to investigate the influence of fibres, three types of fibres in two different lengths (5 and 10 mm) were used, while the amount of fibres was constant. The obtained results show that due to the fibre presence, workability is reduced regardless of the type and length of the fibre. The tested fibres have a negligible effect on compressive strength, but the use of basalt and carbon fibres increases the tensile strength. Furthermore, all three types have positive influence on the toughness and volumetric deformations, although to a greater extent in the use of 10 mm long fibres and carbon fibres.
Effect of Initial Fe Content on Microstructure and Mechanical Properties of Recycled Al-7.0Si-Fe-Mn Alloys with Constant Mn/Fe Ratio
Authors: Song Dongfu , Jia Yiwang , Li Qing , Zhao Yuliang , Zhang Weiwen
Published: February 2022

The effect of initial Fe content on the iron removal efficiency, morphology evolution of the Fe-rich phase and the mechanical properties of the recycled Al-7Si-xFe-1.2xMn alloy during melt holding was studied using an optical microscope (OM), scanning electron microscope (SEM) and tensile testing. The results show that with the increase of the initial Fe content, the residual Fe concentration of the alloys gradually increased, and the corresponding removal efficiency of Fe gradually was increased to 77.67%. The type of Fe-rich phase in the alloys changes from α-Al15(FeMn)3Si2 to a mixture of α-Al15(FeMn)3Si2 and β-Al5FeSi, and its morphological evolution is as follows: coarse Chinese-script + polygon → dense Chinese-script + polygon → polygonal + dense Chinese-script + plate-like. Furthermore, the morphology of the Fe-rich phase in the slag changes from a polygonal shape to an irregular shape with a two-layer structure. The formation and increase of the inner layer with high Mn-content in the irregular-shape phase is the main reason for the increasing residual Fe content. The plasticity of the alloy increases obviously with the increase of the initial Fe content, but the formation of the β-Al5FeSi with plate-like morphology in higher Fe-containing alloy may hinder further improvement of the plasticity.
Advanced Carbon Reinforced Concrete Technologies for Façade Elements of Nearly Zero-Energy Buildings
Authors: Kraft Robert , Kahnt Alexander , Grauer Otto , Thieme Mike , Wolz Daniel Sebastian , Schlüter Dominik , Tietze Matthias , Curbach Manfred , Holschemacher Klaus , Jäger Hubert , Böhm Robert
Published: February 2022

The building sector accounts for approx. 40% of total energy consumption and approx. 36% of all greenhouse gas emissions in Europe. As the EU climate targets for 2030 call for a reduction of greenhouse gas emissions by more than half compared to the emissions of 1990 and also aim for climate neutrality by 2050, there is an urgent need to achieve a significant decrease in the energy use in buildings towards Nearly Zero-Energy Buildings (nZEBs). As the energy footprint of buildings includes the energy and greenhouse gas consumption both in the construction phase and during service life, nZEB solutions have to provide energy-efficient and less carbon-intensive building materials, specific thermal insulation solutions, and a corresponding design of the nZEB. Carbon reinforced concrete (CRC) materials have proven to be excellent candidate materials for concrete-based nZEBs since they are characterized by a significantly lower CO2 consumption during component production and much a longer lifecycle. The corresponding CRC technology has been successively implemented in the last two decades and first pure CRC-based buildings are currently being built. This article presents a novel material system that combines CRC technology and suitable multifunctional insulation materials as a sandwich system in order to meet future nZEB requirements. Because of its importance for the life cycle stage of production, cost-efficient carbon fibers (CF) from renewable resources like lignin are used as reinforcing material, and reinforcement systems based on such CF are developed. Cutting edge approaches to produce ultra-thin lightweight CF reinforced concrete panels are discussed with regard to their nZEB relevance. For the life cycle stage of the utilization phase, the thermal insulation properties of core materials are optimized. In this context, novel sandwich composites with thin CRC layers and a cellular lightweight concrete core are proposed as a promising solution for façade elements as the sandwich core can additionally be combined with an aerogel-based insulation. The concepts to realize such sandwich façade elements will be described here along with a fully automated manufacturing process to produce such structures. The findings of this study provide clear evidence on the promising capabilities of the CRC technology for nZEBs on the one hand and on the necessity for further research on optimizing the energy footprint of CRC-based structural elements on the other hand.
Inflated Unit-Birnbaum-Saunders Distribution
Authors: Martínez-Flórez Guillermo , Tovar-Falón Roger , Barrera-Causil Carlos
Published: February 2022

The modeling different data behaviour like the human development index as a function of life expectancy, the water capacity of a reservoir with respect to a certain threshold, or the percentage of death rate of an infant before his or her first birthday, are situations which a researcher can face. It is noteworthy that these problems may have in common data with excessive zeros and ones. Then, it is essential to have flexible and accuracy models to fit data with these features. Given the relevance of data modeling with excessive zeros and ones, in this paper, a mixture of discrete and continuous distributions is proposed for modeling data with these behaviors. Additionally, the Unit-Birnbaum-Saunders distribution is considered with the aim to explain the continuous component of the model and the features of a Bernoulli process. The estimation of the parameters is based on the maximum likelihood method. Observed and expected information matrices are derived, illustrating interesting aspects of the likelihood approach. Finally, with practical applications by using real data we can show the advantage of using our proposal concerning the inflated beta model.
Balancing the Electromagnetic Field Exposure in Wireless Multi-Hop Networks: An EMF-Aware Routing Scheme
Authors: Iancu Voichiţa , Diez Luis , Sluşanschi Emil , Agüero Ramón
Published: February 2022

This work is situated at the conjunction of the fields of distributed systems, telecommunications, and mathematical modeling, aiming to offer solutions to the problem of people’s overexposure to electro-magnetic fields (EMF) radiation. In this paper, we propose a new routing scheme for wireless multi-hop networks, which seeks a fairer distribution of the exposure to electromagnetic fields, by leveraging a combination of the transmitted power and the accumulated exposure as a routing metric. We carry out a holistic approach, including: (1) an algorithmic study, (2) an analytical model of the aforementioned novel routing metric, and (3) the specification of a routing protocol. We make a performance assessment of our novel routing protocol and the corresponding algorithm, by means of an extensive simulation campaign over the NS-3 simulator. The obtained results yield that the proposed novel solution is able to not only fairly distribute the exposure, but also to reduce its average value, thus enhancing the user experience. We also show that the power consumption using the EMF-aware proposed solution, based on Cycle Canceling Algorithm (CCA), and that observed with an approach seeking power reduction are alike. Indeed, even if there exist key-differences from the user experience’s point of view between both routing approaches, there is no statistically relevant power increase between them. Thus, our solution manages to keep the consumed power at a low level, and at the same time it reduces the overall nodes’ exposure to EMF.
Pathwise Convergent Approximation for the Fractional SDEs
Authors: Kubilius Kęstutis , Medžiūnas Aidas
Published: February 2022

Fractional stochastic differential equation (FSDE)-based random processes are used in a wide spectrum of scientific disciplines. However, in the majority of cases, explicit solutions for these FSDEs do not exist and approximation schemes have to be applied. In this paper, we study one-dimensional stochastic differential equations (SDEs) driven by stochastic process with Hölder continuous paths of order 1/2<γ<1. Using the Lamperti transformation, we construct a backward approximation scheme for the transformed SDE. The inverse transformation provides an approximation scheme for the original SDE which converges at the rate h2γ, where h is a time step size of a uniform partition of the time interval under consideration. This approximation scheme covers wider class of FSDEs and demonstrates higher convergence rate than previous schemes by other authors in the field.
Life Cycle Assessment of an Integrated Membrane Treatment System of Anaerobic-Treated Palm Oil Mill Effluent (POME)
Authors: Razman Khalisah Khairina , Hanafiah Marlia M. , Mohammad Abdul Wahab , Lun Ang Wei
Published: February 2022

A life cycle assessment of anaerobic-treated palm oil mill effluent (POME) was conducted to assess the environmental performance on two integrated treatment processes: the typical hollow fiber membrane ultrafiltration module coupled with adsorption and electro-oxidation as pretreatment. The analysis was undertaken using the ReCiPe 2016 method and SimaPro v9 software was employed using a ‘cradle-to-gate’ approach. The results showed that hollow fiber membrane from the adsorption integrated membrane impacted significantly at 42% to 99% across all impact categories for both processes. Overall, the electro-oxidation integrated membrane was discovered to have a lesser environmental impact, particularly on the ozone formation (human health) (HOFP) at 0.38 kg NOx-eq in comparison to the adsorption integrated membrane at 0.66 kg NOx-eq. The total characterization factor of the endpoint category for human health is 8.61 × 10−4 DALY (adsorption integrated membrane) and 8.45 × 10−4 DALY (electro-oxidation integrated membrane). As membrane treatment is closely linked to energy consumption, the environmental impact with different sources of energy was evaluated for both processes with the impacts decreasing in the following order: Grid > Biogas > Grid/Solar. Future research should concentrate on determining the overall ‘cradle-to-grave’ environmental impact of treating POME, as well as other scenarios involving membrane treatment energy utilization using LCA. This study can help decision-makers in identifying an environmentally sustainable POME treatment and management, especially in Malaysia.
Electrical Properties of Model Lipid Membranes
Authors: Naumowicz Monika
Published: February 2022

Biological membranes are essential components of the living systems, and processes occurring with their participation are related mainly to electric phenomena such as signal transduction, existence of membrane potentials, and transport through the membrane [...]
Structure–Properties–Processing Relationships in Metallic Materials
Authors: Papaefthymiou Spyros
Published: February 2022

The steady innovation of materials has been assisted by the introduction of simulation and analytical technique tools in the development chain [...]
Microstructure, Hot Deformation Behavior, and Textural Evolution of Mg-3Sn-2Al-1Zn-0.6Nd Alloy
Authors: Guo Yuhang , Dai Yibo , Chen Pan , Zang Qianhao , Zhang Zhenya
Published: February 2022

To prepare wrought magnesium alloys with excellent plastic deformation properties, Mg-3Sn-2Al-1Zn-0.6Nd alloys were prepared. A hot compression test of Mg-3Sn-2Al-1Zn-0.6Nd alloy was carried out on a thermo-mechanical simulator. The hot deformation behavior of the alloys was studied, and the constitutive equations and the processing map at the strain of 0.8 were established. The processing map exhibited the stable domain (temperature range of 320–350 °C and strain rate range of 0.001–0.04 s−1) with the high power dissipation efficiency (>30%). A large number of fine dynamic recrystallization (DRX) grains and deformed twinning existed in the alloy after the hot deformation. The dominant texture of the Mg-3Sn-2Al-1Zn-0.6Nd alloy is <0001>//CD texture after the hot deformation. The continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX) were the dominant recrystallization mechanisms, and {101¯2} extension twinning also occurred in the alloy during the hot deformation.
Evolution of Interface Microstructure and Tensile Properties of AgPd30/CuNi18Zn26 Bilayer Laminated Composite Manufactured by Rolling and Annealing
Authors: Wang Yong , Xu Yonghong , Zhang Pei , Yang Xianjun , Chen Yi
Published: February 2022

An AgPd30/CuNi18Zn26 bilayer laminated composite (BLC) was manufactured by hot-roll bonding followed by two passes of cold-rolling and three passes of annealing. The evolution of the interface microstructure during the manufacturing process was investigated using a scanning electron microscope, an electron probe microanalyzer, an X-ray diffractometer and a transmission electron microscope. It was found that a net atomic flow of Zn and Cu immigrated from the CuNi18Zn26 layer into the AgPd30 layer, leading to the formation of a Cu3Au-type superstructure of Cu2NiZn in the former and a diffusion layer in the later. The clusters enriched in Zn and Pd were formed in the diffusion layer and their number varied during the rolling and annealing process. The thickness of the diffusion layer was increased by annealing and decreased by cold rolling. Several intermetallic compounds were identified, which are Pd2Zn, PdZn, Pd2Zn3, PdZn2, Pd3Zn10 and Cu3Pd. Some orientation relationships between the compounds and the AgPd30 alloy were determined to be (310)PdZn2//(111)AgPd and (114)Cu3Pd//(311)PdZn2//(321)Pd3Zn10. Delamination occurred in all 6 samples during tensile testing, including an as-bonded one, two as-rolled ones and three as-annealed ones, but its degree decreased successively with the progress of rolling and annealing. Two turning points appear on the tensile curves of as-annealed samples, which are ascribed to the initiation of delamination and the yield of the metal matrix. However, the tensile curves of the as-bonded and as-rolled samples are smooth.
Semi-Automated Microfluidic Device Combined with a MiniPCR-Duplex Lateral Flow Dipstick for Screening and Visual Species Identification of Lymphatic Filariae
Authors: Phuakrod Achinya , Kusuwan Navapon , Sripumkhai Witsaroot , Pattamang Pattaraluck , Wongkamchai Sirichit
Published: February 2022

Lymphatic filariasis (LF) is a leading cause of permanent disability worldwide that has been listed as a neglected tropical disease by the World Health Organization. Significant progress made by the Global Program to Eliminate Lymphatic Filariasis (GPELF) has led to a substantial decline in the population of the worm that causes LF infection. Diagnostic assays capable of detecting low levels of parasite presence are needed to diagnose LF. There is also a need for new tools that can be used in areas where multiple filarial species are coendemic and for mass screening or for use in a point-of-care setting. In the present study, we applied our previously developed semi-automated microfluidic device in combination with our recently developed mini polymerase chain reaction (miniPCR) with a duplex lateral flow dipstick (DLFD) (miniPCR-DLFD) for rapid mass screening and visual species identification of lymphatic filariae in human blood. The study samples comprised 20 Brugia malayi microfilariae (mf) positive human blood samples, 14 Wuchereria bancrofti mf positive human blood samples and 100 mf negative human blood samples. Microfilariae detection and visual species identification was performed using the microfluidic device. To identify the species of the mf trapped in the microfluidic chips, DNA of the trapped mf was extracted for miniPCR amplification of W. bancrofti and B. malayi DNA followed by DLFD. Thick blood smear staining for microfilariae detection was used as the gold standard technique. Microfilariae screening and visual species identification using our microfluidic device plus miniPCR-DLFD platform yielded results concordant with those of the gold standard thick blood smear technique. The microfluidic device, the miniPCR and the DLFD are all portable and do not require additional equipment. Use of this screening and visual species identification platform will facilitate reliable, cost-effective, and rapid surveillance for the presence of LF infection in resource-poor settings.
A Thermocycler Using a Chip Resistor Heater and a Glass Microchip for a Portable and Rapid Microchip-Based PCR Device
Authors: Yeom Dongsun , Kim Jeongtae , Kim Sungil , Ahn Sanghoon , Choi Jiyeon , Kim Youngwook , Koo Chiwan
Published: February 2022

This study proposes a rapid and inexpensive thermocycler that enables rapid heating of samples using a thin glass chip and a cheap chip resistor to overcome the on-site diagnostic limitations of polymerase chain reaction (PCR). Microchip PCR devices have emerged to miniaturize conventional PCR systems and reduce operation time and cost. In general, PCR microchips require a thin-film heater fabricated through a semiconductor process, which is a complicated process, resulting in high costs. Therefore, this investigation substituted a general chip resistor for a thin-film heater. The proposed thermocycler consists of a compact glass microchip of 12.5 mm × 12.5 mm × 2 mm that could hold a 2 μL PCR sample and a surface-mounted chip resistor of 6432 size (6.4 mm × 3.2 mm). Improving heat transfer from the chip resistor heater to the PCR reaction chamber in the microchip was accomplished via the design and fabrication of a three-dimensional chip structure using selective laser-induced etching, a rapid prototyping technique that allowed to be embedded. The fabricated PCR microchip was combined with a thermistor temperature sensor, a blower fan, and a microcontroller. The assembled thermocycler could heat the sample at a maximum rate of 28.8 °C/s per second. When compared with a commercially available PCR apparatus running the same PCR protocol, the total PCR operating time with a DNA sample was reduced by about 20%.
Processing and Profile Control of Microhole Array for PDMS Mask with Femtosecond Laser
Authors: Zhang Xifang , Yao Zhenqiang , Hou Zhibao , Song Jiacheng
Published: February 2022

Polydimethylsiloxane (PDMS) is hailed as one of the foundational materials that have been applied to different products in various fields because of its chemical resistance, low cost, excellent flexibility, and high molding capability. With the aim to achieve surface texture with high efficiency by means of electrochemical micromachining with PDMS mask, a femtosecond laser is utilized to process a precision array of micro-through-holes on PDMS films as the molds. The ablation process of PDMS with a femtosecond laser was investigated via numerical simulation verified with experiments indicating a laser energy density of 4.865 mJ/mm2 as the ablation threshold of PDMS with the melting temperature of 930 K. The spiral scanning path with optimized radial offset was developed to ablate materials from the PDMS film to form the laminated profiles, and a tapered through hole was then formed with multilayer scanning. The profile dimension and accuracy were examined as control targets in terms of laser pulse energy and scanning speed, showing that a 12 μJ femtosecond laser pulse energy and 1000 mm/s scanning speed could bring about a nearly circular laminating profile with expected smaller exit diameter than the entry diameter. All the cross-section diameters of the microcone decreased with the increase of laser scanning speed, while the taper increased gradually and then saturated around a laser scanning speed of 800 mm/s due to the energy absorption resulting in smaller ablation in diameter and depth.
Research on Compound PID Control Strategy Based on Input Feedforward and Dynamic Compensation Applied in Noncircular Turning
Authors: Zhang Yong , Huang Yue , Wang Yu
Published: February 2022

The fast tool servo (FTS) control strategy is the control core of high-speed noncircular turning. This method should ensure high-speed and precision positioning and have the corresponding anti-interference ability in the micro-stroke motion with dynamic changes of tool feed and load. Most of the previous FTS control studies used the repetitive control and speed feedforward control strategy, which achieved promising results under ideal machining conditions. However, this strategy showed some defects in the real-world complex and changeable working conditions such as time-varying cutting force, intermittent cutting and fluctuating machine spindle speed. This paper proposed and implemented a compound proportional integral derivative control strategy based on input feedforward and dynamic compensation in noncircular turning. This technique successfully met the motion requirements of the high responsiveness of micro-stroke in noncircular turning and overcame disturbances from complex time variations of the cutting force, intermittent cutting case of the product and fluctuations of machine spindle speed. According to the findings, the machining tracking error was less than ±2 µm. Experimental results demonstrated the excellent tracking performance and machining effect of this control strategy.
Easy Removal of Epiphytic Bacteria on Ulva (Ulvophyceae, Chlorophyta) by Vortex with Silica Sands
Authors: Liu Xiaojie , Zhao Jin , Jiang Peng
Published: February 2022

Macroalgae-associated bacteria play an important role in their algal hosts’ biological processes. They are localized on surfaces of the host thalli, as well as between and even within algal cells. To examine the differences in community structures and functions between epi- and endo- bacteria, an effective approach for maximizing epiphyte removal from delicate seaweeds while retaining endophyte fidelity must be developed. In this study, a variety of surface sterilization methods for Ulva prolifera were compared, including mechanical, chemical, and enzymatical treatments. According to the results of scanning electron microscope (SEM) and denaturing gradient gel electrophoresis (DGGE) analysis, almost complete removal of epiphytic bacteria on Ulva was obtained simply by co-vortex of seaweeds with silica sands, causing minimal disturbance to endosymbionts when compared to previous published methods. In addition, the adaptability was also confirmed in additional U. prolifera strains and Ulva species with blade-like or narrow tubular thallus shapes. This easy mechanical method would enable the analysis of community composition and host specificity for Ulva-associated epi- and endo-bacteria separately.
Shallow-Water Hydrothermal Vents as Natural Accelerators of Bacterial Antibiotic Resistance in Marine Coastal Areas
Authors: Arcadi Erika , Rastelli Eugenio , Tangherlini Michael , Rizzo Carmen , Mancuso Monique , Sanfilippo Marilena , Esposito Valentina , Andaloro Franco , Romeo Teresa
Published: February 2022

Environmental contamination by heavy metals (HMs) poses several indirect risks to human health, including the co-spreading of genetic traits conferring resistance to both HMs and antibiotics among micro-organisms. Microbial antibiotic resistance (AR) acquisition is enhanced at sites anthropogenically polluted by HMs, as well as in remote systems naturally enriched in HMs, such as hydrothermal vents in the deep sea. However, to date, the possible role of hydrothermal vents at shallower water depths as hot spots of microbial AR gain and spreading has not been tested, despite the higher potential risks associated with the closer vicinity of such ecosystems to coasts and human activities. In this work, we collected waters and sediments at the Panarea shallow-water hydrothermal vents, testing the presence of culturable marine bacteria and their sensitivity to antibiotics and HMs. All of the bacterial isolates showed resistance to at least one antibiotic and one HM and, most notably, 80% of them displayed multi-AR on average to 12 (min 8, max 15) different antibiotics, as well as multi-HM tolerance. We show that our isolates displayed high similarity (≥99%) to common marine bacteria, affiliating with Actinobacteria, Gammaproteobacteria, Alphaproteobacteria and Firmicutes, and all displayed wide growth ranges for temperature and salinity during in vitro physiological tests. Notably, the analysis of the genomes available in public databases for their closest relatives highlighted the lack of genes for AR, posing new questions on the origin of multi-AR acquisition in this peculiar HM-rich environment. Overall, our results point out that shallow-water hydrothermal vents may contribute to enhance AR acquisition and spreading among common marine bacteria in coastal areas, highlighting this as a focus for future research.
Metagenomic Assessment of DNA Viral Diversity in Freshwater Sponges, Baikalospongia bacillifera
Authors: Butina Tatyana V. , Petrushin Ivan S. , Khanaev Igor V. , Bukin Yurij S.
Published: February 2022

Sponges (type Porifera) are multicellular organisms that give shelter to a variety of microorganisms: fungi, algae, archaea, bacteria, and viruses. The studies concerning the composition of viral communities in sponges have appeared rather recently, and the diversity and role of viruses in sponge holobionts remain largely undisclosed. In this study, we assessed the diversity of DNA viruses in the associated community of the Baikal endemic sponge, Baikalospongia bacillifera, using a metagenomic approach, and compared the virome data from samples of sponges and Baikal water (control sample). Significant differences in terms of taxonomy, putative host range of identified scaffolds, and functional annotation of predicted viral proteins were revealed in viromes of sponge B. bacillifera and the Baikal water. This is the evidence in favor of specificity of viral communities in sponges. The diversity shift of viral communities in a diseased specimen, in comparison with a visually healthy sponge, probably reflects the changes in the composition of microbial communities in affected sponges. We identified many viral genes encoding the proteins with metabolic functions; therefore, viruses in Baikal sponges regulate the number and diversity of their associated community, and also take a part in the vital activity of the holobiont, and this is especially significant in the case of damage (or disease) of these organisms in unfavorable conditions. When comparing the Baikal viromes with similar datasets of marine sponge (Ianthella basta), in addition to significant differences in the taxonomic and functional composition of viral communities, we revealed common scaffolds/virotypes in the cross-assembly of reads, which may indicate the presence of some closely related sponge-specific viruses in marine and freshwater sponges.
Nonhemolytic Listeria monocytogenes—Prevalence Rate, Reasons Underlying Atypical Phenotype, and Methods for Accurate Hemolysis Assessment
Authors: Kawacka Iwona , Olejnik-Schmidt Agnieszka , Schmidt Marcin
Published: February 2022

Listeria monocytogenes is a foodborne pathogen that typically presents β-hemolytic activity. However, there are literature reports indicating that L. monocytogenes strains are sometimes nonhemolytic or their zones of hemolysis are perceivable only after removal of the colonies from the agar plate. Nonhemolytic L. monocytogenes are most commonly encountered in food products, but some have also been detected in clinical samples. Usually, atypical bacteria of this species belong to serotype 1/2a. Mutations of the prfA gene sequence are the most common reason for changed phenotype, and mutations of the hly gene are the second most common cause. There are also reports that the methodology used for detecting hemolysis may influence the results. Sheep or horse blood, although most commonly used in modern studies, may not allow for the production of clear hemolytic zones on blood agar, whereas other types of blood (guinea pig, rabbit, piglet, and human) are more suitable according to some studies. Furthermore, the standard blood agar plate technique is less sensitive than its modifications such as bilayer or top-layer (overlay) techniques. The microplate technique (employing erythrocyte suspensions) is probably the most informative when assessing listerial hemolysis and is the least susceptible to subjective interpretation.
Cupriavidus metallidurans CH34 Possesses Aromatic Catabolic Versatility and Degrades Benzene in the Presence of Mercury and Cadmium
Authors: Alviz-Gazitua Pablo , Durán Roberto E. , Millacura Felipe A. , Cárdenas Franco , Rojas Luis A. , Seeger Michael
Published: February 2022

Heavy metal co-contamination in crude oil-polluted environments may inhibit microbial bioremediation of hydrocarbons. The model heavy metal-resistant bacterium Cupriavidus metallidurans CH34 possesses cadmium and mercury resistance, as well as genes related to the catabolism of hazardous BTEX aromatic hydrocarbons. The aims of this study were to analyze the aromatic catabolic potential of C. metallidurans CH34 and to determine the functionality of the predicted benzene catabolic pathway and the influence of cadmium and mercury on benzene degradation. Three chromosome-encoded bacterial multicomponent monooxygenases (BMMs) are involved in benzene catabolic pathways. Growth assessment, intermediates identification, and gene expression analysis indicate the functionality of the benzene catabolic pathway. Strain CH34 degraded benzene via phenol and 2-hydroxymuconic semialdehyde. Transcriptional analyses revealed a transition from the expression of catechol 2,3-dioxygenase (tomB) in the early exponential phase to catechol 1,2-dioxygenase (catA1 and catA2) in the late exponential phase. The minimum inhibitory concentration to Hg (II) and Cd (II) was significantly lower in the presence of benzene, demonstrating the effect of co-contamination on bacterial growth. Notably, this study showed that C. metallidurans CH34 degraded benzene in the presence of Hg (II) or Cd (II).
Study on the Grinding Law of Ball Media for Cassiterite–Polymetallic Sulfide Ore
Authors: Yang Jinlin , Deng Xingjian , Xu Wenzhe , Li Hengjun , Ma Shaojian
Published: February 2022

To solve the problem involved in the grinding of cassiterite–polymetallic sulfide ore in which fine grinding causes the cassiterite to be overground or coarse grinding leads to inadequate liberation of sulfide minerals, the influences of the ball grinding medium on the size distribution of the grinding product were investigated. Two types of ball filling patterns, namely, single-sized and multi-sized ball grinding media, were adopted in wet batch grinding tests. The results show that increasing the grinding time resulted in a rapid increase in minus 0.038 mm particles and a slight increase in the Sn grade in this fine size fraction. The smaller the ball filling fraction was, the more obviously the ball size affected the size distribution of the grinding product, the variation of which with the ball size became complicated with the increase in the ball filling fraction. Obvious jumping phenomena in the plotting of the percentages of the discussed size fractions against the ball size were observed when the balling filling fraction was larger than 30%; the most obvious jumping phenomena took place at a 35% ball filling fraction. The results of the grinding tests with the multi-sized media show that the size distribution of the grinding product was closely related to that of the mixed ball sizes and their composition percentages.
Effects of Magmatic Fluids in Coals of São Pedro da Cova Coalfield, Douro Carboniferous Basin, Portugal: Insights from Inorganic Geochemistry
Authors: Costa Mariana , Moura Helena , Pinto de Jesus Ary , Suárez-Ruiz Isabel , Flores Deolinda
Published: February 2022

The Douro Carboniferous Basin (DCB), aged from Gzhelian, is an important coal-bearing basin occurring in Northern Portugal. While the coals and the sedimentary sequence of the DCB have been deeply studied, the inorganic geochemical data are scarce. This study intends to provide major and trace element contents and discuss their modes of occurrence and origins using a set of twenty-four coal samples from the São Pedro da Cova Coalfield taken from different sectors/outcrops. Thus, an integrated approach using petrographic, geochemical, both organic and inorganic, and mineralogical data was used to achieve these purposes. The main results demonstrated that these coals are anthracite A and vitrinite is the main organic component. Most of the elements have inorganic affinities and are associated with aluminosilicates, while the other elements have affinities with sulfides. Illite and muscovite are the main phyllosilicates occurring in these coals and pyrite is the most common sulfide. However, cinnabar, together with phosphates (fluorapatite, monazite, xenotime and gorceixite), were also identified. The enrichment of most elements as well as a heterogenous rare earth elements (REE) distribution pattern in the tectono-sedimentary unit (TSU) samples are related to magmatic fluids. On the other hand, on the Eastern Outcrop (EO), a tectonic slice, the subparallel trend of the REE distribution patterns, and a depletion of all the elements are related to the sedimentary contribution. The occurrence of cinnabar and gorceixite epigenetic mineralizations is interpreted as the action of a porphyry intrusion identified in this area of the DCB, between the TSU B1 and TSU D1.
New Ceramics Precursors Containing Si and Ge Atoms—Cubic Germasilsesquioxanes—Synthesis, Thermal Decomposition and Spectroscopic Analysis
Authors: Skoczeń Aleksandra , Frąckowiak Dawid , Przekop Robert E. , Frydrych Miłosz , Kasperkowiak Małgorzata , Jeleń Piotr , Sitarz Maciej , Marciniec Bogdan
Published: February 2022

Compounds of the silsesquioxane type are attractive material precursors. High molecular weights and well-defined structures predestine them to create ceramics with a controlled composition at the molecular level. New molecular precursors of ceramic materials with the ratio of Si:Ge = 7:1 atoms were obtained. The influence of organic substituents on the thermal decomposition processes of germasilsesquioxanes was investigated. Some of the structures obtained are characterized by a high non-volatile residue after the thermal decomposition process. The introduction of the germanium atom to the structure of the silsesquioxane molecular cage reduces the thermal stability of the obtained structures.
CNSL, a Promising Building Blocks for Sustainable Molecular Design of Surfactants: A Critical Review
Authors: Roy Audrey , Fajardie Pauline , Lepoittevin Bénédicte , Baudoux Jérôme , Lapinte Vincent , Caillol Sylvain , Briou Benoit
Published: February 2022

Surfactants are crystallizing a certain focus for consumer interest, and their market is still expected to grow by 4 to 5% each year. Most of the time these surfactants are of petroleum origin and are not often biodegradable. Cashew Nut Shell Liquid (CNSL) is a promising non-edible renewable resource, directly extracted from the shell of the cashew nut. The interesting structure of CNSL and its components (cardanol, anacardic acid and cardol) lead to the synthesis of biobased surfactants. Indeed, non-ionic, anionic, cationic and zwitterionic surfactants based on CNSL have been reported in the literature. Even now, CNSL is absent or barely mentioned in specialized review or chapters talking about synthetic biobased surfactants. Thus, this review focuses on CNSL as a building block for the synthesis of surfactants. In the first part, it describes and criticizes the synthesis of molecules and in the second part, it compares the efficiency and the properties (CMC, surface tension, kraft temperature, biodegradability) of the obtained products with each other and with commercial ones.