bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Decomposition Process Analysis of Jarosite Residue
Authors: Lu Diankun , Bai Yunlong , Wang Wei , Fu Yan , Xie Feng , Chang Yongfeng , Han Yuexin
Published: January 2023

In this work, a mineralogical study and thermal decomposition analysis of jarosite residue sample from a zinc plant were carried out. The mineralogical analysis showed that the jarosite residue is mainly composed of four components, including jarosites, sulfates–hydroxides, sulfides and spinel. The distribution of relevant metallic elements in these components was characterized using a sequential extraction process. The X-ray diffraction results showed that AFe3(OH)6(SO4)2 and ZnFe2O4 are the main components of the jarosite residue sample. The thermal decomposition mechanisms of ammoniojarosite and sodium jarosite were studied by TG-DSC (Thermogravimetric analysis–differential scanning calorimetry). The thermal decomposition process and the corresponding mechanism of the jarosite residue were analyzed. The jarosite thermal decomposition process includes the removal of crystal water, dihydroxylation and deammoniation, desulfonation of component jarosite and desulfonation of component zinc sulfate.
Microstructure and Mechanical Properties of LaB6/Ti-6Al-4V Composites Fabricated by Selective Laser Melting
Authors: He Dongdong , Wang Hui , Huang Weidong , Chen Xinxi , Lian Guofu , Wang Yu
Published: January 2023

In this study, TiB + La2O3/Ti-6Al-4V composites were successfully prepared by in situ reaction using selective laser melting technology. The effect of LaB6 content on the fabrication quality, microstructure evolution and mechanical properties of the composite samples was investigated. The results show that the relative density of the sample gradually decreased from 98.56% to 96.57% as LaB6 content increased from 0 wt% to 3 wt%. With increasing LaB6 content, TiB precipitates gradually aggregated and grew from a discrete needle-like structure to a dendritic structure, before eventually developing a cell-like structure. The dislocations piled up around the TiB and La2O3 reinforcements, which impeded the motion of the dislocations and led to the enhancement of the tensile strength of the samples. Different from the addition of a single reinforcement due to the combined strengthening effect of the micrometer-scale and nanoscale reinforcements, the strength of the samples was increased significantly. The Ti-6Al-4V sample with 3 wt% LaB6 addition showed the most significant strengthening effect. Compared to the pure Ti-6Al-4V sample, the 3 wt% LaB6 addition sample gained a 35.71% increase in hardness and a 14.5% increase in tensile strength. Additionally, wear volume was reduced by 47.5%. The results revealed that the addition of LaB6 was a potential way to improve the mechanical performance of the titanium alloys in the additive manufacturing process.
Reduced Friction and Excellent Anti-Wear Performance of QBe2 Beryllium Bronze against 38CrMoAlA Steel in Pneumatic Downhole Motor under Grease Lubrication
Authors: Liang Chenfan , Zhou Jing , Wang Yu , Peng Zhijian
Published: January 2023

To improve the service life of the newly designed pneumatic downhole motor, a kind of commercially available lithium complex grease was used to help avoid the rapid wear-induced failure of the dynamic seal of pneumatic downhole tools in operation. The investigation on the tribological behaviors of QBe2 beryllium bronze and 38CrMoAlA steel tribo-pairs in pneumatic downhole motor revealed that under lubrication, the instantaneous friction coefficient and wear volume became very low, showing greatly reduced friction and excellent anti-wear performance. Compared with the case without lubrication, the adhesive wear mechanism and ploughing effect of the tribo-pairs were significantly alleviated. Moreover, Cu and Fe were oxidized to form composite oxides between the frictional surface, further improving the lubrication effect between the QBe2 beryllium bronze and 38CrMoAlA steel. Notably, the test could be operated stably for more than 150 h under lubrication, fully reaching the requirement of pneumatic downhole tools under actual drilling conditions. These results provide a solid support for the practical application of the reported pneumatic downhole tools.
LPBF-Formed 2024Al Alloys: Process, Microstructure, Properties, and Thermal Cracking Behavior
Authors: Yao Sen , Wang Jiajian , Li Min , Chen Zhen , Lu Bingheng , Shen Song , Li Yao
Published: January 2023

2024Al is an Al-Cu-Mg series heat-treatable aluminum alloy with high strength and excellent damage resistance. To obtain a high-performance target component of LPBF-formed 2024Al, the effect of process parameters on density, microstructure, and performance is systematically investigated and the thermal cracking phenomenon is analyzed in detail. The results reveal that the optimization of process parameters can suppress the cracks generated during the LPBF forming of 2024Al to a certain extent. When the laser energy density is 741 J/mm3, the maximum density reaches 99.77%, whereas the tensile strength and elongation reach 330 ± 7 MPa and 9 ± 0.6%, respectively. Owing to the high Cu and Mg contents in 2024Al, the transverse strain rate of columnar grains during LPBF forming is easily higher than the sum of the transverse expansion rate of grains and the liquid phase filling rate at grain boundaries, resulting in strong thermal crack sensitivity. In addition, an extremely high cooling rate (−108 K/s) and heat input during LPBF forming reduce the liquid phase filling rate at grain boundaries to further aggravate the thermal cracking tendency. The current study provides experimental guidance for the preparation of high-quality, crack-less, or even crack-free 2024Al alloys.
Archaeometallurgical Explorations of Bloomery Iron Smelting at Mutoti 2, an Early Iron Age Site in Venda, Northern South Africa
Authors: Mathoho Eric N. , Nyamushosho Robert T. , Chirikure Shadreck
Published: January 2023

When established, bloomery iron smelting profoundly transformed farming communities that settled in Africa south of the Sahara. Sustained research in the Lowveld region of northern South Africa identified multifarious evidence of metal working dating to the Early Iron Age (Common Era 200-900). Not surprisingly, the region is celebrated in oral traditions, myths, legends, and other reservoirs of local knowledge for its highly skilled metallurgists who reduced exceptionally rich magnetite (Fe3O4) and hematite (Fe2O3) ores at locales such as Tshimbupfe, Tshirululuni, Vuu, Thomo, and Thengwe. However, the technology of iron smelting and how the smelted iron (Fe) transformed producer and user communities in the region is a subject that, until recently, attracted limited archaeometallurgical work. We present the results of archaeometallurgical analyses of iron production remains from Mutoti 2 using complementary macroscopic (physical examination), microstructural (Optical Microscopy), and compositional techniques (WD-XRF). The results show that the technology of iron smelting fitted within the bloomery method. However, the quantities of iron production remains at the site suggest a scale and organization of production geared for needs beyond single villages. This embedded first-millennium CE iron production into the socio-economic, political, and environmental transformations that shaped the political economy of farming communities of the time.
Oxidation-Affected Erosion of Porous Ni-Al Intermetallic Alloy in Combustion Applications: Pore-Scale Simulation
Authors: Yakovlev Igor , Astakhov Daniil , Zambalov Sergey , Pichugin Nikita , Maznoy Anatoly
Published: January 2023

Advanced high-temperature oxidation resistance is a crucial characteristic of metallic materials in porous burners. Extreme combustion conditions could lead to oxidation-affected erosion of porous media at a long-time period of burner operation. In this paper, we numerically simulated oxide scale growth at a porous radiant burner fabricated by Ni-Al intermetallic alloy using the combustion synthesis method, focusing on the structure degradation caused by periodic oxide scale spallation. A three-dimensional geometrical model of a porous intermetallic scaffold was obtained by scanning the porous burner using the X-ray CT technique. The surface erosion was modeled by the surface reconstruction based on calculated values of spalled oxide layer thickness. The simulation revealed that the submerged flame results in non-uniform distribution of the temperature at the solid surface. Such non-isothermal conditions lead to a two-times thicker oxide scale at the external surface of the burner. Thin struts of the intermetallic scaffold are prone to oxidation-affected erosion first, which forms discontinues and further fragmentation. The porous scaffold could lose about 50% of initial weight before fragmentation under conditions with intense oxide spallation. In such large structural degradation, the average flow velocity could reduce by a factor of 3, leading to changing of flame stabilization region.
Predictive Equations Overestimate Resting Metabolic Rate in Young Chilean Women with Excess Body Fat
Authors: Maury-Sintjago Eduard , Rodríguez-Fernández Alejandra , Ruíz-De la Fuente Marcela
Published: January 2023

Underestimating/overestimating resting metabolic rate (RMR) affects energy prescription. The objective was to compare RMR by indirect calorimetry (RMR IC) and RMR estimated by predictive equations in women with excess body fat. This was an analytical cross-sectional study with 41 women aged 18–28 with overnutrition according to body composition. The RMR IC was measured and RMR estimated using the FAO/WHO/UNU (1985), FAO/WHO/UNU (2004), Harris–Benedict, and Mifflin–St Jeor equations. The percentage of adequacy (90–110%), overestimation (>110%), and underestimation (<90%) were evaluated for RMR IC. Data were described by percentiles because of non-normal distribution according to the Shapiro–Wilk test. The Kruskal–Wallis test and Bland–Altman analysis were applied at a significance level of α < 0.05. The RMR IC was 1192 and 1183 calories/day (p = 0.429) in women with obesity and overweight, respectively. The FAO/WHO/UNU (1985), FAO/WHO/UNU (2004), Harris–Benedict, and Mifflin–St Jeor equations overestimated the RMR IC by 283.2, 311.2, 292.7, and 203.0 calories/day and by 296.7, 413.8, 280.0, and 176.6 calories/day for women with overweight and obesity (p < 0.001), respectively. The Harris–Benedict adjusted weight (0.5) equation underestimated RMR IC by 254.7 calories/day. The predictive equations overestimated RMR IC in women with excess body fat. The Mifflin–St Jeor equation showed less overestimation and better adequacy, but was not exempt from inaccuracy.
Analysis of the Differences in Muscle Nutrition among Individuals of Different Sexes in Redclaw Crayfish, Cherax quadricarinatus
Authors: Sun Yuyan , Shan Xin , Li Desheng , Liu Xuxiao , Han Zongao , Qin Junjie , Guan Bin , Tan Leilei , Zheng Jianbo , Wei Min , Jia Yongyi
Published: January 2023

Redclaw crayfish (Cherax quadricarinatus) was introduced to China many years ago. In recent years, a breeding boom for C. quadricarinatus has been set off in China due to a breakthrough in key technology of seedling breeding. The size and growth rate of C. quadricarinatus vary greatly between female and male individuals, usually the size and growth rate of male individuals are bigger than that of female individuals. There is usually a certain linkage relationship between the sex traits of crustaceans and their own nutrition. In order to explore the linkage relationship between the sex traits of C. quadricarinatus and its nutritional components, this study measured and analyzed the muscle nutritional components of female and male individuals. The results showed that the meat yield rate of male individuals was significantly higher than that of females (p < 0.05), and the crude fat content was significantly lower than that for females (p < 0.05). The ratios of essential amino acids to total amino acids for females and males were 39.61% and 38.49%, respectively. The ratios of essential amino acids to non-essential amino acids were 79.69% and 75.66%, respectively, which far exceed FAO/WHO standards and both belong to high-quality protein. The total amount of flavor amino acids of male individuals was significantly higher than that of female individuals (p < 0.05). The total amount of polyunsaturated fatty acids and the polyunsaturated fatty acid eicosapentaenoic acid of males are both significantly higher than that of females (p < 0.05). Studies have shown that there are certain differences in nutrition between male and female individuals. Compared with female individuals, the meat yield rate, crude protein content, and edible value of the muscles of male individuals is higher.
Capacity of HDL to Efflux Cellular Cholesterol from Lipid-Loaded Macrophages Is Reduced in Patients with Familial Hypercholesterolemia
Authors: Ganjali Shiva , Hosseini Susan , Rizzo Manfredi , Kontush Anatol , Sahebkar Amirhossein
Published: January 2023

This study aimed to evaluate the high-density lipoprotein (HDL) capacity to efflux cellular cholesterol from lipid-loaded macrophages to find a reliable and low-cost biomarker with the purpose of better evaluating the risk of premature cardiovascular (CV) events in FH patients. This case-controlled study comprised 16 homozygous (HOFH) and 18 heterozygous (HEFH) FH patients, as well as 20 healthy subjects recruited as controls. Two main subfractions of HDL (HDL2 (d = 1.063–1.125 g/mL) and HDL3 (d = 1.125–1.210 g/mL)) were isolated from the patients’ serum samples using sequential ultracentrifugation. After compositional characterization, the capacity of HDL to efflux cholesterol (CEC%) from lipid-laden macrophages was measured. The HDL2 and HDL3 subfractions showed some differences in lipid and protein composition between the studied groups. In addition, both HDL subfractions (p < 0.001) revealed significantly reduced CEC% in HOFH patients (HDL2: 2.5 ± 0.1 and HDL3: 3.2 ± 0.2) in comparison with the HEFH (HDL2: 3.2 ± 0.1% and HDL3: 4.1 ± 0.2%) and healthy (HDL2: 3.3 ± 0.2% and HDL3: 4.5 ± 0.3%) subjects. Additionally, multinomial logistic regression results indicated that the CEC% of both HDL2 (OR: 0.091; 95% CI: 0.018–0.452, p < 0.01) and HDL3 (OR: 0.118; 95% CI: 0.035–0.399, p < 0.01) subfractions are strongly and inversely associated with the homozygous form of FH. A decreased capacity of HDL particles to efflux cholesterol from macrophages might identify homozygous FH patients who are at elevated risk for premature CVDs. Prospective studies with a large sample size are warranted to evaluate this hypothesis.
Application of 1H HR-MAS NMR-Based Metabolite Fingerprinting of Marine Microalgae
Authors: Caprara Carolina da Silva Canielles , Mathias Tatiane Ksyvickas , Santos Maria de Fátima C. , D’Oca Marcelo G. M. , D’Oca Caroline Da R. M. , Roselet Fabio , Abreu Paulo Cesar , Ramos Daniela Fernandes
Published: January 2023

Natural products from the marine environment as well as microalgae, have been known for the complexity of the metabolites they produce due to their adaptability to different environmental conditions, which has been an inexhaustible source of several bioactive properties, such as antioxidant, anti-tumor, and antimicrobial. This study aims to characterize the main metabolites of three species of microalgae (Nannochloropsis oceanica, Chaetoceros muelleri, and Conticribra weissflogii), which have important applications in the biofuel and nutrition industries, by 1H High-resolution magic angle spinning nuclear magnetic resonance (1H HR-MAS NMR), a method which is non-destructive, is highly reproducible, and requires minimal sample preparation. Even though the three species were found in the same ecosystem and a superior production of lipid compounds was observed, important differences were identified in relation to the production of specialized metabolites. These distinct properties favor the use of these compounds as leaders in the development of new bioactive compounds, especially against environmental, human, and animal pathogens (One Health), and demonstrate their potential in the development of alternatives for aquaculture.
Quantitation and Distribution of Epichloë-Derived Alkaloids in Perennial Ryegrass Tissues
Authors: Vassiliadis Simone , Reddy Priyanka , Hemsworth Joanne , Spangenberg German C. , Guthridge Kathryn M. , Rochfort Simone J.
Published: January 2023

Perennial ryegrass (Lolium perenne L.), an economically important pasture and turf grass, is commonly infected with asexual Epichloë species endophytes. Endophytes provide enhanced bioprotection by producing alkaloids, and research often focusses on the negative impact on grazing animals. However, alkaloid distribution throughout the plant and their role in biocontrol of insect pests and diseases are less well understood. Additionally, intermediate compounds have not been investigated for their impacts on animal welfare and biological control in pasture-based scenarios. Here, a single liquid chromatography–mass spectrometry (LC-MS) method was used to measure seven alkaloids in different perennial ryegrass tissues infected with SE or NEA12 endophytes. High alkaloid recoveries and a clear plant matrix effect emphasize the importance of using matrix-matched standards for accurate quantitation. The method is sensitive, detecting alkaloids at low concentrations (nanogram levels), which is important for endophyte strains that produce compounds detrimental to livestock. Concentrations were generally highest in seeds, but distribution differed in the shoots/roots: peramine, terpendole E, terpendole C and lolitrem B were higher in shoots, whilst ergovaline, paxilline and epoxy-janthitrem I were more evenly distributed throughout the two tissues. Knowledge of alkaloid distribution may allow for concentrations to be predicted in roots based on concentrations in the shoots, thereby assisting future determinations of resistance to insects, especially subterranean root-feeding pests.
Zwitterionic Polymer Coated and Aptamer Functionalized Flexible Micro-Electrode Arrays for In Vivo Cocaine Sensing and Electrophysiology
Authors: Wu Bingchen , Castagnola Elisa , Cui Xinyan Tracy
Published: January 2023

The number of people aged 12 years and older using illicit drugs reached 59.3 million in 2020, among which 5.2 million are cocaine users based on the national data. In order to fully understand cocaine addiction and develop effective therapies, a tool is needed to reliably measure real-time cocaine concentration and neural activity in different regions of the brain with high spatial and temporal resolution. Integrated biochemical sensing devices based upon flexible microelectrode arrays (MEA) have emerged as a powerful tool for such purposes; however, MEAs suffer from undesired biofouling and inflammatory reactions, while those with immobilized biologic sensing elements experience additional failures due to biomolecule degradation. Aptasensors are powerful tools for building highly selective sensors for analytes that have been difficult to detect. In this work, DNA aptamer-based electrochemical cocaine sensors were integrated on flexible MEAs and protected with an antifouling zwitterionic poly (sulfobetaine methacrylate) (PSB) coating, in order to prevent sensors from biofouling and degradation by the host tissue. In vitro experiments showed that without the PSB coating, both adsorption of plasma protein albumin and exposure to DNase-1 enzyme have detrimental effects on sensor performance, decreasing signal amplitude and the sensitivity of the sensors. Albumin adsorption caused a 44.4% sensitivity loss, and DNase-1 exposure for 24 hr resulted in a 57.2% sensitivity reduction. The PSB coating successfully protected sensors from albumin fouling and DNase-1 enzyme digestion. In vivo tests showed that the PSB coated MEA aptasensors can detect repeated cocaine infusions in the brain for 3 hrs after implantation without sensitivity degradation. Additionally, the same MEAs can record electrophysiological signals at different tissue depths simultaneously. This novel flexible MEA with integrated cocaine sensors can serve as a valuable tool for understanding the mechanisms of cocaine addiction, while the PSB coating technology can be generalized to improve all implantable devices suffering from biofouling and inflammatory host responses.
On-Line Fluorescence Microscopy for Identification and Imaging of Apoptotic Cell with Synchrotron-Based Soft X-ray Tomography
Authors: Zhang Chao , Wu Zhao , Dang Zheng , Tian Lijiao , Guan Yong , Liu Gang , Tian Yangchao
Published: January 2023

Synchrotron-based soft X-ray tomography (SXT), providing three-dimensional morphology and quantitative distribution of linear absorption coefficient (LAC) of the imaged objects, is widely used in many fields to obtain ultra-structure images, especially in cellular imaging. Off-line fluorescence microscopies (FMs) are combined to identify the type of organelles and status of cells. However, deformation and displacement usually occur during the transfer and loading process, which decreases the precision of two-modal images’ registration. In this paper, we report on an on-line FM, at the SXT station (BL07W) of the National Synchrotron Radiation Laboratory (NSRL), which avoids deformation and displacement. Therefore, researchers can easily find the sample and take the useful data without tedious post-processing. Combining SXT with on-line FM, we achieved the identification and high-resolution imaging of an apoptotic cell. The experiments revealed that the LAC of the nucleus of the apoptotic cell was larger than that of a normal cell, which could be explained by nucleus pyknosis of the apoptotic cell.
Experimental and Numerical Investigation of the Die Swell in 3D Printing Processes
Authors: De Rosa Stefano , Tammaro Daniele , D’Avino Gaetano
Published: January 2023

Fused deposition modelling is one of the most widely used additive manufacturing techniques and the diffusion of 3D printers has increased in popularity even further in recent times. Since high precision is required in 3D printing, a good control over the extrusion process is necessary. In this regard, a crucial phenomenon to be accounted for is the die or extrudate swell, i.e., the enlargement of the cross-section of the strand when coming out of the printer nozzle. While this phenomenon has been studied in large scale extruders, it has not yet been investigated in depth for 3D printing processes. In this work, the die swell phenomenon observed in a printed PLA filament is studied by experiments and fluid dynamic simulations. A novel, easy-to-use, accurate and fast procedure for measuring the value of the die swell ratio during the printing process is developed, accounting for typical errors related to a non-constant strand diameter and possible oscillations of the filament with respect to the extrusion direction. As the printing velocity is increased, a linearly increasing swelling ratio is observed at low printing speeds. The trend flattens at moderate speed values. A sudden increase is found at high printing velocities. The swelling ratio measured with the proposed technique is compared with the results of multi-mode viscoelastic simulations at different temperatures. A fair agreement between the experimental measurements and the numerical predictions is found for printing velocities that are typically employed in commercial 3D printers, supporting the reliability of the developed procedure.
Multiband Signal Receiver by Using an Optical Bandpass Filter Integrated with a Photodetector on a Chip
Authors: Han Xiuyou , Chao Meng , Su Xinxin , Wang Weiheng , Fu Shuanglin , Wu Zhenlin , Zhao Mingshan
Published: January 2023

Photonic integration brings the promise of significant cost, power and space savings and propels the real applications of microwave photonic technology. In this paper, a multiband radio frequency (RF) signal simultaneous receiver using an optical bandpass filter (OBPF) integrated with a photodetector (PD) on a chip is proposed, which was experimentally demonstrated. The OBPF was composed of ring-assisted Mach–Zehnder interferometer with a periodical bandpass response featuring a box-like spectral shape. The OBPF was connected to a PD and then integrated onto a single silicon photonic chip. Phase-modulated multiband RF signals transmitted from different locations were inputted into the OBPF, by which one RF sideband was filtered out and the phase modulation to intensity modulation conversion was realized. The single sideband with carrier signals were then simultaneously detected by the PD. A proof-of-concept experiment with the silicon photonic integrated chip was implemented to simultaneously receive four channels of 8 GHz, 12 GHz, 14 GHz and 18 GHz in the X- and Ku-bands. The performance of the integrated microwave photonic multiband receiver—including the receiving sensitivity, the spurious free dynamic range, the gain and the noise figure across the whole operation frequency band—was characterized in detail.
Machine Learning Algorithm for Efficient Design of Separated Buffer Super-Junction IGBT
Authors: Kim Ki Yeong , Hwang Tae Hyun , Song Young Suh , Kim Hyunwoo , Kim Jang Hyun
Published: January 2023

An improved structure for an Insulated Gate Bipolar Transistor (IGBT) with a separated buffer layer is presented in order to improve the trade-off between the turn-off loss (Eoff) and on-state voltage (Von). However, it is difficult to set efficient parameters due to the increase in the new buffer doping concentration variable. Therefore, a machine learning (ML) algorithm is proposed as a solution. Compared to the conventional Technology Computer-Aided Design (TCAD) simulation tool, it is demonstrated that incorporating the ML algorithm into the device analysis could make it possible to achieve high accuracy and significantly shorten the simulation time. Specifically, utilizing the ML algorithm could achieve coefficients of determination (R2) of Von and Eoff of 0.995 and 0.968, respectively. In addition, it enables the optimized design to fit the target characteristics. In this study, the structure proposed for the trade-off improvement was targeted to obtain the minimum Eoff at the same Von, especially by adjusting the concentration of the separated buffer. We could improve Eoff by 36.2% by optimizing the structure, which was expected to be improved by 24.7% using the ML approach. In another way, it is possible to inversely design four types of structures with characteristics close to the target characteristics (Eoff = 1.64 μJ, Von = 1.38 V). The proposed method of incorporating machine learning into device analysis is expected to be very strategic, especially for power electronics analysis (where the transistor size is comparatively large and requires significant computation). In summary, we improved the trade-off using a separated buffer, and ML enabled optimization and a more precise design, as well as reverse engineering.
Approximate Priority Hybrid 3DNoC Buffered-Bufferless Router
Authors: Savva Savvas , Tatas Konstantinos , Kyriacou Costas
Published: January 2023

This paper introduces a novel 3D NoC router that combines buffered and bufferless routing with approximate priority comparison when deflecting flits. Our proposal is a modification of an asymmetrical router that is buffered in the z dimension ports and bufferless in the x and y dimension ports. Flits that request output ports in the x and y dimensions are granted or deflected based on approximate, instead of accurate, priority comparison. Experimental results show that the proposed router, in addition to effectively combining the advantages of both buffered and bufferless routers, achieves additional performance and area gains due to the reduced logic required for approximate priority comparison in flit deflections. Experimental results using synthetic and realistic traffic show that the proposed router begins to saturate at a significantly higher injection rate than a bufferless router, but at a slightly lower injection rate than when using accurate priority comparison. Furthermore, the proposed router achieves higher clock frequencies and a reduced area compared to bufferles routers due to the simpler permutation network. The increased routing efficiency is shown to also translate to energy gains.
A VO2 Neuristor Based on Microstrip Line Coupling
Authors: Lin Haidan , Shen Yiran
Published: January 2023

The neuromorphic network based on artificial neurons and synapses can solve computational difficulties, and its energy efficiency is incomparable to the traditional von Neumann architecture. As a new type of circuit component, nonvolatile memristors are very similar to biological synapses in structure and function. Only one memristor can simulate the function of a synapse. Therefore, memristors provide a new way to build hardware-based artificial neural networks. To build such an artificial neural network, in addition to the artificial synapses, artificial neurons are also needed to realize the distribution of information and the adjustment of synaptic weights. As the VO2 volatile local active memristor is complementary to nonvolatile memristors, it can be used to simulate the function of neurons. However, determining how to better realize the function of neurons with simple circuits is one of the current key problems to be solved in this field. This paper considers the influence of distribution parameters on circuit performance under the action of high-frequency and high-speed signals. Two Mott VO2 memristor units are connected and coupled with microstrip lines to simulate the Hodgkin–Huxley neuron model. It is found that the proposed memristor neuron based on microstrip lines shows the characteristics of neuron action potential: amplification and threshold.
Polishing Approaches at Atomic and Close-to-Atomic Scale
Authors: Geng Zhichao , Huang Ning , Castelli Marco , Fang Fengzhou
Published: January 2023

Roughness down to atomic and close-to-atomic scale is receiving an increasing attention in recent studies of manufacturing development, which can be realized by high-precision polishing processes. This review presents polishing approaches at atomic and close-to-atomic scale on planar and curved surfaces, including chemical mechanical polishing, plasma-assisted polishing, catalyst-referred etching, bonnet polishing, elastic emission machining, ion beam figuring, magnetorheological finishing, and fluid jet polishing. These polishing approaches are discussed in detail in terms of removal mechanisms, polishing systems, and industrial applications. The authors also offer perspectives for future studies to address existing and potential challenges and promote technological progress.
Manipulation, Sampling and Inactivation of the SARS-CoV-2 Virus Using Nonuniform Electric Fields on Micro-Fabricated Platforms: A Review
Authors: Mantri Devashish , Wymenga Luutzen , van Turnhout Jan , van Zeijl Henk , Zhang Guoqi
Published: January 2023

Micro-devices that use electric fields to trap, analyze and inactivate micro-organisms vary in concept, design and application. The application of electric fields to manipulate and inactivate bacteria and single-celled organisms has been described extensively in the literature. By contrast, the effect of such fields on viruses is not well understood. This review explores the possibility of using existing methods for manipulating and inactivating larger viruses and bacteria, for smaller viruses, such as SARS-CoV-2. It also provides an overview of the theoretical background. The findings may be used to implement new ideas and frame experimental parameters that optimize the manipulation, sampling and inactivation of SARS-CoV-2 electrically.
Supplementation of Sulfide or Acetate and 2-Mercaptoethane Sulfonate Restores Growth of the Methanosarcina acetivorans ΔhdrABC Deletion Mutant during Methylotrophic Methanogenesis
Authors: Salvi Alicia M. , Chowdhury Niaz Bahar , Saha Rajib , Buan Nicole R.
Published: January 2023

Methanogenic archaea are important organisms in the global carbon cycle that grow by producing methane gas. Methanosarcina acetivorans is a methanogenic archaeum that can grow using methylated compounds, carbon monoxide, or acetate and produces renewable methane as a byproduct. However, there is limited knowledge of how combinations of substrates may affect metabolic fluxes in methanogens. Previous studies have shown that heterodisulfide reductase, the terminal oxidase in the electron transport system, is an essential enzyme in all methanogens. Deletion of genes encoding the nonessential methylotrophic heterodisulfide reductase enzyme (HdrABC) results in slower growth rate but increased metabolic efficiency. We hypothesized that increased sulfide, supplementation of mercaptoethanesulfonate (coenzyme M, CoM-SH), or acetate would metabolically alleviate the effect of the ΔhdrABC mutation. Increased sulfide improved growth of the mutant as expected; however, supplementation of both CoM-SH and acetate together were necessary to reduce the effect of the ΔhdrABC mutation. Supplementation of CoM-SH or acetate alone did not improve growth. These results support our model for the role of HdrABC in methanogenesis and suggest M.acetivorans is more efficient at conserving energy when supplemented with acetate. Our study suggests decreased Hdr enzyme activity can be overcome by nutritional supplementation with sulfide or coenzyme M and acetate, which are abundant in anaerobic environments.
Interaction between Illite and a Pseudomonas stutzeri-Heavy Oil Biodegradation Complex
Authors: Li Lei , Wan Yun Yang , Mu Hong Mei , Shi Sheng Bao , Chen Jian Fa
Published: January 2023

Illite is a widely distributed clay mineral with huge reserves in Earth’s crust, but its effect on heavy oil biodegradation is rarely reported. This study made an investigation of the interactions between illite and a Pseudomonas stutzeri-heavy oil complex (PstHO). Results showed that, although illite exerted a negative effect on P. stutzeri degrading heavy oil by inhibiting the biodegradation of 64 saturated hydrocarbons (SHs) and 50 aromatic hydrocarbons (AHs), it selectively stimulated the biodegradation of 45 AHs with a specific structure, and its biogenic kaolinization at room temperature (35 °C) and pressure (1 atm) was observed in PstHO for the first time. The finding points out for the first time that, in PstHO, illite may change the quasi-sequential of AHs biodegradation of heavy oil, as well as its kaolinization without clay intermediate.
Weeds: An Insidious Enemy or a Tool to Boost Mycorrhization in Cropping Systems?
Authors: Trinchera Alessandra , Warren Raffa Dylan
Published: January 2023

Weeds have always been considered an insidious enemy, capable of reducing crop production. Conversely, the agroecological vision attributes a key role to the spontaneous flora in promoting plant diversity and belowground interactions, which may improve the ecological performance of agroecosystems. We summarized the literature on the weeds’ arbuscular–mycorrhizae (AM) interaction and we analyzed evidence on the: (i) AM suppressive/selective effect on weed communities; (ii) effect of weeds on AM colonization, and (iii) positive role of AM-supporting weeds on forming shared mycorrhizal hyphal connections in agroecosystems. While some authors conceptualized AM as a weed control tool, others underlined their selective effect on weed communities. Recent studies suggest that AM-host weeds can participate in the development of a common mycorrhizal mycelial network (MMN) among different plants species. Nevertheless, direct evidence of the actual exchange of nutrients and C between coexisting plants through MMN in agroecosystems is missing. Although the effect of agricultural practices on plant community-AM interactions are complex, more conservative farming management seems to foster AM populations. Future studies should focus on: (i) field studies, (ii) weed communities and their traits, rather than on the most abundant species, and (iii) the use of advanced analytical techniques, able to monitor MMN development and functionality.
A One-Year Systematic Study to Assess the Microbiological Profile in Oysters from a Commercial Harvesting Area in Portugal
Authors: Rodrigues Inês C. , Santos-Ferreira Nânci , Silva Daniela , da Silva Carla Chiquelho , Inácio Ângela S. , Nascimento Maria São José , da Costa Paulo Martins
Published: January 2023

As filter-feeding animals farmed in water bodies exposed to anthropogenic influences, oysters can be both useful bioremediators and high-risk foodstuffs, considering that they are typically consumed raw. Understanding the dynamic of bacterial and viral load in Pacific oyster (Crassostrea gigas) tissues, hemolymph, outer shell surface biofilm, and farming water is therefore of great importance for microbiological risk assessment. A one-year survey of oysters collected from a class B production area (Canal de Mira, on the Portuguese western coast) revealed that these bivalve mollusks have a good depurating capacity with regard to bacteria, as Salmonella spp. and viable enterococci were not detected in any oyster flesh (edible portion) samples, despite the fact that these bacteria have regularly been found in the farming waters. Furthermore, the level of Escherichia coli contamination was clearly below the legal limit in oysters reared in a class B area (>230–≤4600 MPN E. coli/100 g). On the contrary, norovirus was repeatedly detected in the digestive glands of oysters sampled in autumn, winter, and spring. However, their presence in farming waters was only detected during winter.
Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): Focus on the Pathophysiological and Diagnostic Role of Viruses
Authors: Ramirez Giuseppe A. , Ripa Marco , Burastero Samuele , Benanti Giovanni , Bagnasco Diego , Nannipieri Serena , Monardo Roberta , Ponta Giacomo , Asperti Chiara , Cilona Maria Bernadette , Castagna Antonella , Dagna Lorenzo , Yacoub Mona-Rita
Published: January 2023

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a heterogeneous, multiorgan and potentially life-threatening drug-hypersensitivity reaction (DHR) that occurs several days or weeks after drug initiation or discontinuation. DHRs constitute an emerging issue for public health, due to population aging, growing multi-organ morbidity, and subsequent enhanced drug prescriptions. DRESS has more consistently been associated with anticonvulsants, allopurinol and antibiotics, such as sulphonamides and vancomycin, although new drugs are increasingly reported as culprit agents. Reactivation of latent infectious agents such as viruses (especially Herpesviridae) plays a key role in prompting and sustaining aberrant T-cell and eosinophil responses to drugs and pathogens, ultimately causing organ damage. However, the boundaries of the impact of viral agents in the pathophysiology of DRESS are still ill-defined. Along with growing awareness of the multifaceted aspects of immune perturbation caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the ongoing SARS-CoV-2-related disease (COVID-19) pandemic, novel interest has been sparked towards DRESS and the potential interactions among antiviral and anti-drug inflammatory responses. In this review, we summarised the most recent evidence on pathophysiological mechanisms, diagnostic approaches, and clinical management of DRESS with the aim of increasing awareness on this syndrome and possibly suggesting clues for future research in this field.
Plasmid Composition, Antimicrobial Resistance and Virulence Genes Profiles of Ciprofloxacin- and Third-Generation Cephalosporin-Resistant Foodborne Salmonella enterica Isolates from Russia
Authors: Egorova Anna , Shelenkov Andrey , Kuleshov Konstantin , Kulikova Nina , Chernyshkov Aleksey , Manzeniuk Igor , Mikhaylova Yulia , Akimkin Vasiliy
Published: January 2023

Salmonella enterica is an important foodborne pathogen worldwide. Ciprofloxacin and extended-spectrum cephalosporins are the common first-line antimicrobial drugs for the treatment of salmonellosis, antimicrobial resistance genes for which are mostly transferred via plasmids. The goal of this work was to perform genomic analysis of plasmids from foodborne S. enterica isolates obtained in Russia based on whole-genome sequencing. In the current study, 11 multidrug-resistant samples isolated in 2021 from 8 regions of Russia were selected based on their resistance to ciprofloxacin and third-generation cephalosporins (CIP-3rd). Whole-genome short-read sequencing (WGS) was performed for all isolates; the samples belonged to five different sequence types (ST32, ST469, ST11, ST142, and ST548) which had different profiles of antimicrobial resistance (AMR) and virulence genes. We have performed additional long-read sequencing of four representative S. enterica isolates, which showed that they carried pESI-like megaplasmids of 202–280 kb length harboring extended-spectrum β-lactamase genes, fluoroquinolone, tetracycline, and aminoglycosides resistance genes, as well as several virulence determinants. We believe that the WGS data obtained will greatly facilitate further studies of foodborne S. enterica isolates epidemiology in terms of their self-transmissible plasmid composition that mediated antimicrobial resistance and virulence determinants conferring selective advantages of this important bacterial pathogen.
Design and Application of a Deep-Sea Engineering Geology In Situ Test System
Authors: Zhong Kaiming , Chen Ming , Xie Chao , Zheng Jinrong , Chen Wei , Ou Wen , Yu Chunliang
Published: January 2023

Seabed soil layer composed of soft sediments, which has a high water content, low bulk density and low shear strength, has great influence on deep-sea engineering devices. Therefore, accurate measurement of the mechanical properties of seabed sediments is a prerequisite for the construction and safe operation of deep-sea projects. In this study, a deep-sea engineering geology in situ test system was developed to measure cone resistance, sleeve friction, pore pressure and shear resistance in seafloor sediments. The system was tested on land, and the feasibility of the system was verified. We conducted sea trials in the South China Sea and acquired datasets from five stations. The data were analyzed using the Eslami–Fellenius soil classification map, and the soil classification of the site was obtained. The obtained values of cone resistance, sleeve friction, pore pressure and shear resistance can provide mechanical data support for deep-sea engineering in this area.
Use of Seashell and Limestone Fillers in Metakaolin-Based Geopolymers for Masonry Mortars
Authors: Assaad Joseph Jean , Saba Marianne
Published: January 2023

Mortars intended for plastering and masonry works normally comply to EN 413-1 and/or ASTM C91 specifications. This paper seeks to assess the suitability of geopolymers (GPs) composed of metakaolin and seashell wastes for masonry applications. The sodium hydroxide and sodium silicate activators contained air-entraining molecules to secure about 10% ± 2% air content. Just like the cement-based mortars, test results showed that the mechanical properties of GPs including the compressive strength, flexural strength, pull-off adhesion, and water sorptivity decreased when the seashell concentration increased in the mixture. This was mainly related to a dilution effect that reduces the aluminosilicate precursor content and formation of rigid bonds. The replacement of limestone filler by seashell powder slightly increased the mechanical properties, which was attributed to higher seashell hardness that densifies the microstructure and provides additional resistance to support the external stresses. Yet, the grinding of seashells into fine powder required higher energy than what is needed for the comminution of clinker or limestone. The use of GPs is particularly advantageous for masonry applications, as it speeds up the construction operations while eliminating the hassle of moist curing normally required with cement-based plasters.
In Situ U—Pb Dating and Trace Element Analysis of Garnet in the Tongshanling Cu Polymetallic Deposit, South China
Authors: Tan Fucheng , Kong Hua , Liu Biao , Wu Qianhong , Chen Shefa
Published: January 2023

The grossular–andradite garnet is an ideal mineral for indicating the formation age of skarn, which also pretends to constrain skarn processes because of its higher REE (rare earth elements) content. The Tongshanling deposit is a medium-sized reduced skarn Cu–W–Pb–Zn deposit associated with a highly evolved I-type granodiorite intrusion in the Nanling metallogenic belt, South China. Different mineral assemblages, microscopic characteristics, and BSE images distinguish two kinds of garnets in the prograde and retrograde skarn stages. The garnet grains from the prograde skarn stage have a U–Pb isochron age of 165.4 ± 3.8 Ma (MSWD = 0.7) and that from the retrograde skarn stage have a U–Pb isochron age of 159.5 ± 1.7 Ma (MSWD = 1.8), implying that the thermal metamorphism and hydrothermal metasomatism mainly occurred in the middle Upper Jurassic. The total amount of rare earth elements (∑REE+Y) in the garnet gradually decreased and the REE patterns shifted from enriched HREE with Eu negative anomaly to HREE-depleted with Eu positive anomaly. The decreasing U content and increasing Eu anomaly in the retrograde skarn stage indicate a redox environment change from oxidation to reduction. However, garnet from different elevations within the same stage (+90 m, +5 m, −35 m, −200 m, and −400 m) exhibit similar REE patterns, despite weak cooling and significant depressurization processes confirmed by fluid inclusion microthermography. As a result, the REE content and patterns are dominated by the REE species of parent fluids, which are changed over time by symbiotic REE-enriched mineral precipitation and the redox environment, while being slightly affected by the fluid pressure. Grossular garnets, rich in U and REEs, and found in reduced skarn deposits, can constrain chronology and reveal the spatio-temporal zonal characteristics.
Differences in Pore Type and Pore Structure between Silurian Longmaxi Marine Shale and Jurassic Dongyuemiao Lacustrine Shale and Their Influence on Shale-Gas Enrichment
Authors: Wang Pengwei , Nie Haikuan , Liu Zhongbao , Sun Chuanxiang , Cao Zhe , Wang Ruyue , Li Pei
Published: January 2023

The Silurian Longmaxi (S1l) marine shale and Jurassic Dongyuemiao (J1d) lacustrine shale in the Sichuan Basin, West China have attracted considerable attention from the oil-and-gas industry in China. Currently, the differences in pore types and pore structures between them are poorly understood, which has limited shale-resource exploration in the Sichuan Basin. This paper systemically compares the pore characteristics of Longmaxi shale and Dongyuemiao shale and investigates their impact on shale-gas enrichment by integrating field-emission scanning electron microscopy (FE–SEM), X-ray diffraction (XRD), low-pressure gas (CO2 and N2) adsorption and mercury-intrusion porosimetry, high-pressure sorption isotherms, gas-saturation measurement, molecular-dynamics simulation, etc. The results show that the S1l organic-rich marine shale and the J1d lacustrine shale have different pore types and pore structures. The S1l shale is dominated by organic pores, mainly micropores and mesopores with ink-bottle-like pore shapes, while the J1d shale is primarily composed of clay-mineral pores, mainly mesopores and macropores with slit- or plate-like pore shapes. Organic pores can provide considerable storage space for shale-gas enrichment in S1l marine shale, which also determines the adsorption capacity of shale reservoirs. Although organic pores are not the most prevalent in the Dongyuemiao lacustrine shale, they also play an important role in enhancing reservoir quality and absorbed-gas enrichment. Clay-mineral pores contribute weakly to the storage space of J1d-lacustrine-shale reservoirs. Mesopores are the most important form of storage space in both S1l shale and J1d shale, contributing significantly to shale-gas enrichment. Micropores are secondary in importance in S1l marine shale, while macropores are secondary contributors to pore volume in J1d lacustrine shale.