The COVID-19 pandemic caused by SARS-CoV-2 dominated the year 2020 and has an unprecedented impact on global air transport. This paper tries to make an overall review on the interaction of air ...transport and the COVID-19 pandemic. Although the confirmed cases were first reported in China, the origin of the pandemic remains uncertain. China was the first country to control the COVID-19 pandemic, and domestic air traffic recovers at a fast pace. Compared to 2019 level, world scheduled capacity, passengers carried, and revenues for 2020 were reduced by 50%, 60%, and $371 billion, respectively. Compared with domestic passenger traffic, international passenger traffic reduces more seats, passengers, and revenues. Because air transport contributes to economic growth, many countries or regions provide aviation bailout. The US provides most direct aid, while China mostly provides policy measures. In the post-COVID-19 period, IATA suggests that accepting vaccinated passengers is the best practice to reopen borders. Air cargo will play an important role in the distribution of COVID-19 vaccines. Meanwhile, air transport should be more digitalized, sustainable, and responsible in the future.
The problem of insufficient hardenability in general large-size parts always occurs in product manufacturing because of their large size, etc. It is restricted mainly by its own alloy composition ...with micro-alloy and key quenching and partitioning (Q&P) process. The relationship between the cooling rate and properties of small samples was analyzed as the basis of the initial cooling rate at different positions corresponding to large-size parts combined with controlled austenization temperature in this work. Typical as-treated microstructure after a fast cooling rate is mainly composed of lath bainite, martensite, and retained austenite (RA), while bainite and RA after a slow cooling rate. Simulations showed that cooling control via decreasing spray intensity, meeting higher strength at the surface, and good strength and toughness match can be obtained both at the surface and in the center. As-treated large ring part has ~ 1330 MPa tensile strength and ~ 95 J impact energy at the surface, and meantime, ~ 1191 MPa tensile strength and ~ 70 J impact energy in the center, which narrows the property difference.
Graphical abstract
Nanocrystalline soft magnetic materials are widely used in power electronic applications due to their high permeability,magnetization and low core loss.In this ...paper,Fe73.5Cu1Nb3Si15.5B7（at%）nanocrystalline alloy ribbons,with ultra-thin thickness of 14μm,and also 18 and 22μm,were prepared by a planar flow casting method with a single roller device.Soft magnetic properties of these ribbons were analyzed after nanocrystallization annealing.The experiments were conducted on toroidal samples using IWATSU B-H Analyzer over a frequency range of 10–100 kHz,at induction amplitudes of 100–500 m T,at room temperature.It was found that the excess eddy current loss Pexwas the dominant factor in the overall core loss above 10 k Hz.The toroidal samples made of the 14μm thickness ribbon exhibit very low total core loss of 48 W/kg at a frequency of100 kHz and magnetic flux density of 300 mT.The ratio of the Pexwas up to 89%at 100 kHz.The ribbon with lower thickness exhibits lower Pexand therefore lower total core loss.The domain structure evidences were found.It indicates that the ribbons with small thickness are preferable for application in high frequency condition.
Circular RNAs (circRNAs) are functional molecules in all kinds of fibrosis diseases. The current study was performed for the exploration of circ_0007535 in pulmonary fibrosis. RNA levels for ...circ_0007535, miR-18a-5p, and transforming growth factor-β receptor 1 (TGFBR1) were assayed via a reverse transcription-quantitative polymerase chain reaction. Cell growth was determined by cell counting kit-8 assay for viability and ethynyl-2’-deoxyuridine assay for proliferation. Cell invasion and migration were examined by transwell assay and scratch assay. Western blot was performed for the detection of different proteins. Enzyme-linked immunosorbent assay was used to assess inflammatory response. The interaction analysis was conducted using dual-luciferase reporter assay, RNA immunoprecipitation assay, and biotin-coupled pull-down assay. Circ_0007535 was significantly upregulated by TGF-β1 in HFL1 cells. TGF-β1-induced proliferation, motility, ECM accumulation, and inflammatory reaction in HFL1 cells were alleviated by circ_0007535 knockdown. Circ_0007535 exhibited interaction with miR-18a-5p, and miR-18a-5p inhibition reversed all influences of circ_0007535 downregulation in TGF-β1-treated HFL1 cells. Circ_0007535 acted as a miR-18a-5p sponge to regulate the expression of downstream target TGFBR1. MiR-18a-5p induced TGFBR1 level inhibition to attenuate TGF-β1-mediated cell injury in HFL1 cells. This study evidenced that circ_0007535 facilitated TGF-β1-induced pulmonary fibrosis by depending on the absorption of miR-18a-5p to upregulate TGFBR1.
SUMMARY
An unarmored dinoflagellate, Karlodinium jejuense sp. nov., was isolated from the northern East China Sea. The species was characterized by light, fluorescence, and scanning electron ...microscopy of laboratory cultures, as well as SSU rDNA, ITS region (ITS1‐5.8S‐ITS2) and LSU rDNA gene sequences. Cells were ellipsoid to oval, small‐sized, 9.9–16.0 μm in length and 6.2–12.7 μm in width. The chloroplasts were 7–10 in number and yellow‐green in color. The central nucleus was large, located in the center of the cell. The linear apical groove with outward thick rolled margins was very short, and there was no ventral pore. Small pores were irregularly distributed on the cell surface. The amphiesmal vesicles were hexagonal and pentagonal. Karlodinium jejuense was morphologically similar to K. ballantinum but differed in cell surface characteristics and swimming pattern. The partial LSU sequence of K. jejuense differed by 3.7–4.1% from that of K. ballantinum. Molecular phylogenetic analyses of multi‐gene sequences revealed that K. jejuense was an independent species nested within the Karlodinium clade. Phylogenetic analysis based on partial LSU rDNA gene sequences indicated that K. jejuense was most closely related to K. gentienii and K. ballantinum.
Taxonomy and Ecology of Marine Algae Park, Bum Soo; Li, Zhun
Journal of marine science and engineering,
01/2022, Letnik:
10, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The term “algae” refers to a large diversity of unrelated phylogenetic entities, ranging from picoplanktonic cells to macroalgal kelps ...
Dinoflagellates are a major component of the modern plankton. Of the 2192 species of marine free-living dinoflagellates presently described, an increasing number are being shown to produce resting ...cysts (probably hypnozygotes) within their life cycle. With rare exception, only the resting cysts fossilize, so they are of central importance in tracing the history of dinoflagellates through geological time. Cysts of many of the more common dinoflagellate species have distinctive morphologies allowing their geographic and stratigraphic occurrences to be traced. An ever-increasing number of taxa are also being shown to produce distinctive and geologically preservable cysts, potentially enhancing our knowledge of the diverse representation of dinoflagellates through time. Here the organic-walled cysts of 73 rare, poorly known or morphologically problematic marine dinoflagellate cyst species belonging to the orders Gymnodiniales (nine species) and Peridiniales (64 species) are reviewed, described and illustrated, and their stratigraphic ranges assessed. The names Echinidinium aculeatum and Echinidinium transparantum are validated.
•73 rare and endemic marine dinoflagellate cyst species are reviewed, described and illustrated.•9 belong to Gymnodiniales and 64 to Peridiniales.•Echinidinium aculeatum and Echinidinium transparantum are validated.
(
) exhibits the ability to form biofilms as a means of adapting to its adverse surroundings.
in this biofilm state demonstrates remarkable resistance, evades immune system attacks, and poses ...challenges for complete eradication, thereby complicating clinical anti-infection efforts. Moreover, the precise mechanisms governing biofilm formation and disruption remain elusive. Recent studies have discovered that fingolimod (FLD) exhibits biofilm properties against Gram-positive bacteria. Therefore, the antibiofilm properties of FLD were evaluated against multidrug-resistant (MDR)
in this study. The antibiofilm activity of FLD against
was assessed utilizing the Alamar Blue assay along with confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and crystal violet (CV) staining. The results showed that FLD effectively reduced biofilm formation, exopolysaccharide (EPS), motility, and bacterial abundance within
biofilms without impeding its growth and metabolic activity. Furthermore, the inhibitory impact of FLD on the production of autoinducer-2 (AI-2) signaling molecules was identified, thereby demonstrating its notable anti-quorum sensing (QS) properties. The results of qRT-PCR analysis demonstrated that FLD significantly decreased the expression of genes associated with the efflux pump gene (
,
,
,
, and
), outer membrane (OM) porin proteins (
,
), the quorum-sensing (QS) system (
), lipopolysaccharide (LPS) production (
), and EPS production (
). Simultaneously, FLD exhibited evident antibacterial synergism, leading to an increased survival rate of
infected with MDR
. These findings suggested that FLD has substantial antibiofilm properties and synergistic antibacterial potential for colistin in treating
infections.
Microalgae are highly valued for their rapid biomass production and metabolite synthesis, as well as their abundance of beneficial compounds. They have a variety of applications, including serving as ...the primary ingredient in biofuels, functional foods, and cosmetics. The genus Picochlorum, which was established to represent the unique characteristics of “Nannochloris-like” algae, exhibits rapid growth and a high salt tolerance. The morphology, molecular phylogeny, and fatty acid composition of an unspecified Picochlorum strain KCTC AG61293 found in Korean coastal waters were investigated. The strain exhibited a unique cell morphology and reproduction type compared to other Picochlorum species, as determined using light microscopy, fluorescence microscopy, and field emission scanning electron microscopy (FE-SEM). The vegetative cells were elongated and cylindrical in shape, underwent binary fission, and possessed a parietal chloroplast. A molecular phylogenetic analysis using nuclear small subunit ribosomal RNA sequences showed that Picochlorum sp. (KCTC AG61293) belongs to the Picochlorum clade and is closely related to the genus Nannochloris. Compared to other reference species, Picochlorum sp. (KCTC AG61293) had higher levels of saturated fatty acids (SFAs) and alpha-linolenic acid (ALA). The increased levels of SFAs and ALA suggest that Picochlorum sp. (KCTC AG61293) may be a promising candidate for biofuel production and other industrial uses.
A solar heat pump based on the photovoltaic photothermal (PV/T) module is a new technology that can improve the photovoltaic efficiency and recovery of waste heat in photovoltaic conversion. The ...comprehensive efficiency of a system can thus be greatly improved. At present, there is little research on the simulation of a solar heat pump based on the Simulink 2018 software. In this paper, PV/T modules are modeled and simulated using the Simulink software based on the typical meteorological parameters in Beijing city during summer and winter conditions. Considering the system characteristics of a simultaneous operation, the models of all components such as the compressor, condenser, evaporator, expansion valve, and heat storage tanks contained in a system are established based on the system’s working principle, energy conservation equations, and some empirical formulas and then simulated. As PV/T modules are the key influencing factor for system performance, the model and simulation process are introduced in detail in this paper. The results show that the surface temperature of PV/T modules under different operating conditions are all significantly lower than that of ordinary photovoltaic panels. The average temperature of PV/T modules is only 15.2 °C, which is 20.2 °C lower than that of ordinary panels under summer conditions, and the average temperature of PV/T modules is only 0.5 °C, 17.8 °C lower than that of ordinary panels under winter conditions. The average photoelectric efficiency can be improved by 15.4% and 8.9%. And, the temperature change amplitude of PV/T modules is lower, which weakens the temperature fluctuation of the modules. The photovoltaic efficiency is therefore further increased. As a result, the power generation and photovoltaic efficiency are both improved significantly.
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