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The global ocean mass has significantly changed during recent decades, which may induce changes in the abyssal ocean circulation. Due to the lack of in situ observations, the response of the abyssal South China Sea (SCS) circulation to ocean mass changes remains unclear. The ocean state estimate, Estimating the Circulation and Climate of the Ocean (ECCO), provides the long‐term ocean mass changes in terms of ocean bottom pressure (OBP). Here we use the ECCO OBP data to quantify decadal changes in the abyssal SCS circulation and reveal a weakening trend. The OBP gradient trend manifests in forms of an anomalous anticyclonic circulation that is intensified by topographic effects along the continental slopes to reduce the existing abyssal circulation. The weakening abyssal circulation corresponds to the weakening Luzon Strait overflow that yields a decreasing vorticity budget in the abyssal SCS. Plain Language Summary: Caused by global warming, ice melt and long‐term atmospheric forcing changes, ocean mass has been increased and redistributed over the past decades. The changes in ocean mass distribution may lead to changes in abyssal ocean circulation. The changes in the abyssal South China Sea (SCS) circulation remains unclear due to the lack of in situ observations. This study uses the Estimating the Circulation and Climate of the Ocean (ECCO) ocean state estimate to quantify decadal changes in the abyssal SCS circulation. Our analysis of the ECCO ocean bottom pressure data reveals a weakening trend in the abyssal SCS circulation that is consistent with the recently ascertained weakening Luzon Strait overflow. Key Points: Trends in the ECCO ocean bottom pressure (OBP) gradients indicate a decadal weakening abyssal South China Sea (SCS) circulationThe weakening circulation coincides with the weakening Luzon Strait overflow that yields a decreasing vorticity budget in the abyssal SCSThe anomalous anticyclonic circulation is dominated by OBP gradient trends and intensified by topographic effects along continental slopes [ABSTRACT FROM AUTHOR]

The Luzon Strait overflow is a deep current of dense water flowing persistently into the South China Sea (SCS) from the Pacific. It is the primary driving force of the deep SCS circulation and potentially influenced by ocean mass changes. Limited by the lengths of in situ observations, long‐term changes in the Luzon Strait overflow transport (LSOT) have not been ascertained. Based on 14 years of satellite‐based ocean bottom pressure (OBP) time series, here we provide an evidence of a weakening of the LSOT by −0.43 Sv decade−1 between 2003 and 2016. Moreover, both OBP data and mooring time series reveal a large annual cycle in the LSOT. The weakening trend in the LSOT may profoundly influence the deep SCS circulation, as well as heat and mass fluxes between the SCS and surrounding oceans. Plain Language Summary: Deep ocean circulation has been changed for recent decades. Limited by in situ observations, long‐term changes in the Luzon Strait overflow transport (LSOT) is unknown yet. However, it is of great importance as the LSOT is the main driving force of the deep South China Sea circulation. Based on 14‐year ocean bottom pressure data, here we initially provide a satellite‐based evidence on the LSOT changes and reveal a robust weakening trend of −0.43 Sv decade−1 in the LSOT over the past two decades. Key Points: A satellite‐based evidence on changes in the Luzon Strait overflow transport (LSOT) is initially provided and validated by mooring dataChanges in ocean bottom pressure reveal a robust weakening trend of −0.43 Sv decade−1 in the LSOT over the past two decadesAnnual variation is the dominant component in the LSOT and regulated by bottom pressure difference along and across the Luzon Strait [ABSTRACT FROM AUTHOR]

• Enhanced diapycnal mixing in SCS generates a three-layer flow in Luzon Strait. • The three-layer potential vorticity flux induces a sandwiched circulation in SCS. • Circulation in the upper layer varies more frequently than that in the lower layers. • The seasonal variability of the SCS circulation in the lower layers is disputable. The South China Sea (SCS) is a semi-enclosed ocean basin, with its sole deepwater renewal channel in the northeast, the Luzon Strait, connected to the northwestern Pacific. The circulation in the SCS is endowed with a distinctive multi-layer structure, which is influenced by the seasonally reversing Southeast Asian monsoon at the surface, modulated Kuroshio intrusion in the upper layer, and enhanced diapycnal mixing and persistent Luzon Strait deepwater overflow in the deep layer. After being diapycnally mixed by energetic internal tides, internal waves, and mesoscale eddies, waters entering the SCS in the upper and deep layers through the Luzon Strait are returned to the northwestern Pacific in the intermediate layer. This inflow-outflow-inflow structure in vertical induces net inflows of potential vorticity in the upper and deep layers and a net outflow of potential vorticity in the intermediate layer of the Luzon Strait, which are believed to be closely related with the circulation structure in the SCS. A sandwiched circulation in the SCS, namely, anticyclonic in the intermediate layer and cyclonic in the upper and deeper layers, was recently reported, but controversial issues still remain on its spatial pattern and temporal variability. To ascertain this sandwiched circulation and reveal its driving mechanism is of much scientific interest to the on-going discussion on the SCS circulation and its role in regional climate. Different from previous review articles focusing on eddies or circulation in a specific layer or area, we overview the full-depth circulation of the SCS layer-by-layer and outline its possible forcing mechanisms, and furthermore, provide perspectives for further investigation. [ABSTRACT FROM AUTHOR]

Integrodifference equations have been widely used to describe the spatiotemporal dynamics of a population. Here, we first extended the discrete Beverton–Holt model, to model the effects of an instantaneous control measure within each generation on a population’s growth. Then we investigated the effects of instantaneous killing rate and timing of pesticide application on a pest’s dynamics, together with the effects of a spatial factor on the existence of a travelling wave solution, its spreading speed and asymptotic stability, and the occurrence of paradoxical effects. The main results indicate that the instantaneous killing rate significantly influences the existence of a travelling wave and its speed of spread, while the timing of pesticide applications does not. In order to address how such dynamic complexities affect the above results, we included an interruption constant into the model which can generate chaotic dynamics. The results indicate that the pesticide efficacy not only affects the existence of a travelling wave and its speed of spread, but it can also produce paradoxical effects, i.e. low pesticide efficacy can result in an increase, not a decrease, of the stable population size, while high pesticide efficacy could inhibit the pests growth. Furthermore, different patterns of stable population sizes between odd and even generations can be produced. The results reveal that the pest control tactics should be designed according to the spatial characteristics and the pest generation. [ABSTRACT FROM AUTHOR]

The liver is an organ with metabolism as the main function in the human body, and participates in the body's function activities, including deoxidation, storage of liver glycogen and synthesis of secretory proteins. During the development of liver diseases relative, a series of morphological, metabolic and functional changes occur to hepatocytes. The development of powerful tools for monitoring liver diseases relative changes are important for clinical medicine and pharmacy. Small molecule fluorescent probes that are covalently linked to galactose-based scaffolds target hepatocytes specifically through the asialoglycoprotein receptor, a structure expressed primarily on hepatocytes, exhibits high affinity toward carbohydrates, especially glucose, galactose and N -acetylgalactosamine, and promotes internalization through reticulin-mediated endocytosis. These fluorescent probes have become a powerful tool to evaluate the metabolic activity of hepatocytes by monitoring changes in the levels of small molecules such as reactive sulfur species, reactive oxygen species, reactive nitrogen species, and β-galactosidase, and to diagnosis liver cancer cells. Moreover, fluorescent probes that target hepatocytes have been used to detect and image reactive species in liver tissues and in vivo because of their high sensitivity, high selectivity, excellent spatial-temporal resolution and non-invasiveness. In this short review we appraise a series of fluorescent probes that are used to detect and evaluate the metabolic activity of hepatocytes and image hepatocytes in liver tissue. • Recent progress on galactose-based hepatocyte-targeting fluorescent probes are summarized. • The detecting and evaluating liver relative diseases have been overviewed. • Future prospective of galactose-based hepatocyte-targeting fluorescent probes are discussed. [ABSTRACT FROM AUTHOR]

Brain death (BD) induces a systemic inflammatory response that influences donor liver quality. Protease-activated receptor 4 (PAR4) is a thrombin receptor that mediates platelet activation and is involved in inflammatory and apoptotic processes. Therefore, we investigated the role of PAR4 blockade in liver injury induced by BD and its associated mechanisms. In this study, we constructed a BD rat model and treated rats with TcY-NH2, a selective PAR4 antagonist, to block PAR4 signaling at the onset of BD induction. Our results revealed that PAR4 protein expression increased in the livers of rats with BD. PAR4 blockade alleviated liver injury induced by BD, as indicated by lower serum ALT/AST levels and an improvement in histomorphology. Blood platelet activation and hepatic platelet accumulation in BD rats were reduced by PAR4 blockade. Additionally, PAR4 blockade attenuated the inflammatory response and apoptosis in the livers of BD rats. Moreover, the activation of NF-κB and MAPK pathways induced by BD was inhibited by PAR4 blockade. Thus, our results suggest that PAR4 contributes to liver injury induced by BD by regulating inflammation and apoptosis through the NF-κB and MAPK pathways. Thus, PAR4 blockade may provide a feasible approach to improve the quality of organs from BD donors. • PAR4 protein expression increases in livers after brain death. • PAR4 blockade alleviates liver injury induced by brain death. • PAR4 blockade reduces platelet activation and accumulation induced by brain death. • PAR4 blockade reduces inflammatory response and apoptosis induced by brain death. • PAR4 blockade inhibits NF-κB and MAPK pathway activation induced by brain death. [ABSTRACT FROM AUTHOR]

Terahertz spectroscopy is becoming a potential tool for characterizing various materials including biomaterial specimens, liquids, and semiconductors. Accuracy of the sample information is important for analysis. In this article, the influences of type and position of window functions on accuracy of extracting sample information are studied. Experimental results show that an appropriate type and position of window functions significantly improve the accuracy of the extracted sample information. [ABSTRACT FROM PUBLISHER]

In shallow waters, tidal friction at seabed is proportional to the square of tidal current velocity, and can induce shallow water tides. M 2 , S 2 and N 2 are the most important semi-diurnal constituents in the Bohai and Yellow Seas, and their interaction through the frictional nonlinearity can induce shallow water tides, with 2MS 2 and 2MN 2 being the most representative constituents. In this paper, we analyze the observed hourly records at 27 tidal stations along the coast of the Bohai and Yellow Seas and obtain harmonic constants of μ 2 and L 2 constituents, which can be separated into astronomical parts μ 2 ′ and L 2 ′ , and frictional nonlinearity-induced parts, 2MS 2 and 2MN 2 , respectively. A numerical model is also performed to simulate the constituents 2MS 2 and 2MN 2. It shows a fairly good agreement between the model and observations in the harmonic constants of constituents 2MS 2 and 2MN 2. The cotidal charts of 2MS 2 and 2MN 2 are presented. It is found that the frictional nonlinearity-induced shallow water tides can significantly reduce the main fortnightly and monthly modulations. • Harmonic constants of μ 2 and L 2 constituents are obtained from 27 tide gauges. • The nonlinear interplay between M 2 , S 2 and N 2 tides can induce 2MS 2 and 2MN 2 tides. • Nonlinearity-induced shallow water tides reduce main fortnightly and monthly modulations. [ABSTRACT FROM AUTHOR]

A TfOH-catalyzed synthesis of 2,3-dihydro-4(1H)-quinolones fromo-anilinopropargyl alcohols was developed. Studies ofN-protecting groups and substituents in phenyl rings showed that diverse groups could be applied. By controlling the catalyst loading,o-anilinopropargyl alcohols underwent the expected transformation smoothly to produceN-protected orN-deprotected 2,3-dihydro-4 (1H)-quinolones in good yields. This transformation probably involved a tandem Meyer–Schuster rearrangement/intramolecular hydroamination reaction process. [ABSTRACT FROM AUTHOR]

The wind stresses and their derived wind stress curls, and Sverdrup stream functions over the South China Sea (SCS) in typical winter and summer months from nine datasets are compared. The datasets include CCMP, CERSAT, ASCAT, QSCAT, NCEP, QSCAT-NCEP, HR, ERA-40, and ERA-Interim. Results show that the overall patterns of the wind stresses, wind stress curls, and Sverdrup stream functions from different datasets are similar. However, their magnitudes are remarkably different. Among them, ERA-40 is the smallest while HR is the largest. The former is about 40 % smaller than the mean value, while the latter is about 50 % greater than the mean value. The spatial resolution is important for the presentation of the wind stress features in the SCS. It can be expected that the same numerical ocean model driven by different wind stress would yield remarkably different results. [ABSTRACT FROM AUTHOR]

Transcription regulatory sequences (TRSs) play a key role in the synthesis of porcine reproductive and respiratory syndrome virus (PRRSV) subgenomic mRNAs, which resembles similarity-assisted RNA recombination. In this study, genome instability was found when a highly pathogenic PRRSV (HP-PRRSV) strain was inserted by an additional transcription unit in which a foreign gene GFP was expressed from TRS2 while a copy of TRS6 drove ORF2a/b transcription. Structural protein gene-deleted genomes resulted from enhanced RNA recombinations were identified in the recombinant virus rHV-GFP. Moreover, rHV-GFP replicated slower than parental viruses, and caused less cell death in porcine alveolar macrophages. Pigs infected with rHV-GFP survived with no or mild syndromes, whereas all pigs infected with parental viruses died within 12 days. Our data showed that additional transcription unit insertion could confer genome instability and attenuation of HP-PRRSV. [ABSTRACT FROM AUTHOR]

Abstract: The effect of electropulsing treatment (ET) on the microstructure of Mg–3Al–1Zn (AZ31) alloy was investigated. Combing with the calculated temperature of the sample after ET, it was found that electropulsing accelerated dynamic recrystallization (DRX) at a relatively low temperature and a high strain rate. Based on the interplay between the accumulation and annihilation effects of electropulsing, a tentative mechanism of DRX induced by electropulsing was discussed. [Copyright &y& Elsevier]

Abstract: Electropulsing induced dissolution of β-Mg17Al12 phase was investigated using scanning electron microscopy, X-ray diffraction and hardness tests. It was found that compared with conventional heat treatment, electropulsing treatment (EPT) decreased the apparent solid solution temperature of the β phase and accelerated the dissolution of β phase into α-matrix in a very short time of several seconds due to reduction of the nucleation thermodynamic barrier and enhancement of atomic diffusion, respectively. A model for the temperature field of a strip under EPT was established. Based on the contributions of the coupling of the thermal and athermal effects with the free energy and the direct electron–atom interactions, the thermodynamics and kinetics of the electropulsing induced dissolution of β-Mg17Al12 are discussed. [Copyright &y& Elsevier]

Lian, Z.; Wei, Z.X.; Wang, Y.G.; Zhu, Y.H., and Wang, X.Y., 2020. Tidal current and energy flux in the Bohai Strait (China) based on multi-month in-situ observations. In: Guido Aldana, P.A. and Kantamaneni, K. (eds.), Advances in Water Resources, Coastal Management, and Marine Science Technology. Journal of Coastal Research, Special Issue No. 104, pp. 362–370. Coconut Creek (Florida), ISSN 0749-0208. In order to provide a more accurate knowledge for the tidal current and tidal energy flux in the Bohai Strait, current data from two in-situ mooring stations in Bohai Strait with durations up to about 8 months have been analyzed. The result shows that the tidal current is of mixed type, with M2 constituent being dominant and K1 constituent being the second largest in the Bohai Strait. The strong current does occur in the northern Bohai Strait, but its velocity is not as large as we previously expected. The vertical and temporal variations of M2 and K1 harmonic constants are also reported in this paper. At both stations, the tidal energy fluxes of four principal constituents are all toward the Bohai Sea, with a maximum M2 flux density exceeding 60 kW/m at the northern station. The total tidal energy fluxes across the Bohai Strait are as follows: M2, 3.65 GW; S2, 0.38 GW; K1, 0.45 GW; and O1, 0.18 GW. The in situ observations show that the existing models basically agree with observation but certain adjustments are necessary. [ABSTRACT FROM AUTHOR]