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Owing to their distinctive 1,3‐dipolar structure, the catalytic asymmetric hydrogenation of nitrones to hydroxylamines has been a formidable and longstanding challenge, characterized by intricate enantiocontrol and susceptibility to N−O bond cleavage. In this study, the asymmetric hydrogenation and transfer hydrogenation of nitrones were accomplished with a tethered TsDPEN‐derived cyclopentadienyl rhodium(III) catalyst (TsDPEN: p‐toluenesulfonyl‐1,2‐diphenylethylene‐1,2‐diamine), the reaction proceeds via a novel 7‐membered cyclic transition state, producing chiral hydroxylamines with up to 99 % yield and >99 % ee. The practical viability of this methodology was underscored by gram‐scale catalytic reactions and subsequent transformations. Furthermore, mechanistic investigations and DFT calculations were also conducted to elucidate the origin of enantioselectivity. [ABSTRACT FROM AUTHOR]

In microseismic monitoring, the reconstruction of a reliable velocity model is essential for precise seismic source localization and subsurface imaging. However, traditional methods for microseismic velocity inversion face challenges in terms of precision and computational efficiency. In this paper, we use deep learning (DL) algorithms to achieve precise and efficient real-time microseismic velocity modeling, which holds significant importance for ensuring engineering safety and preventing geological disasters in microseismic monitoring. Given that this task was approached as a non-linear regression problem, we adopted and modified the Attention U-Net network for inversion. Depending on the degree of coupling among microseismic events, we trained the network using both single-event and multi-event simulation records as feature datasets. This approach can achieve velocity modeling when dealing with inseparable microseismic records. Numerical tests demonstrate that the Attention U-Net can automatically uncover latent features and patterns between microseismic records and velocity models. It performs effectively in real time and achieves high precision in velocity modeling for Tilted Transverse Isotropy (TTI) velocity structures such as anticlines, synclines, and anomalous velocity models. Furthermore, it can provide reliable initial models for traditional methods. [ABSTRACT FROM AUTHOR]

Based on the hourly rainfall gauge data and ERA5 reanalysis for the period 1980–2020, typical synoptic patterns responsible for summer regional hourly extreme precipitation events (RHEPE) over the middle and lower Yangtze River basin have been objectively identified using a circulation clustering method. It is found that the Meiyu front with different locations and intensities imbedded in the East Asian summer monsoon, and landfalling typhoons are the leading contributors. As the dominant synoptic pattern, the Meiyu front pattern is associated with ∼92% of the total RHEPE occurrence and can be categorized into a southerly strong‐Meiyu type and a northerly weak‐Meiyu type. The RHEPE occurrence shows a predominant morning peak associated with the southerly strong‐Meiyu type and a secondary late afternoon peak related to the northerly weak‐Meiyu type, in which the Meiyu front is pushed northward by the strengthened western North Pacific subtropical high accompanied by accelerated low‐level southwesterly flow. Plain Language Summary: Using ERA5 reanalysis and hourly gauge rainfall measurements in summers of 1980–2020, this study investigates the driving mechanisms and temporal variation of summer regional hourly extreme rainfall events over the middle and lower Yangtze River basin. Typical synoptic patterns responsible for the summer regional hourly rainfall extremes are objectively identified using spectral clustering analysis. The Meiyu front with different locations and intensities imbedded in East Asian summer monsoon and the landfalling typhoons are the synoptic patterns leading to the regional hourly rainfall extremes. The diurnal twin peaks (morning and late afternoon) in the occurrence of regional hourly rainfall extremes are related to the Meiyu front with different locations and intensities. The results from this investigation may help improve the prediction and climate risk assessment of regional extreme rainfall events. Key Points: The Meiyu front imbedded in the East Asian summer monsoon and landfalling typhoons are the leading contributors of summer regional hourly extreme precipitation events (RHEPE) over middle and lower Yangtze River basinThe Meiyu front pattern can be sorted into a southerly type with strong Meiyu front and a northerly type with weak Meiyu frontThe northerly weak Meiyu front pattern with active convection contributes the most to the afternoon diurnal peak of RHEPE occurrence [ABSTRACT FROM AUTHOR]

The incorporation of effective denoising techniques is a crucial requirement for seismic data processing during the acquisition phase due to the inherent susceptibility of the seismic data acquisition process to various forms of interference, such as random and coherent noise. For random noise, the Residual Neural Network (Resnet), with its notable ability to effectively suppress noise in seismic data, has garnered widespread utilization in removing unwanted disturbances or interference due to its elegant simplicity and outstanding performance. Despite the considerable advancements achieved by conventional Resnet in the field of suppressing noise, it is irrefutable that there is still room for amelioration in their ability to filter out unwanted disturbances. As a result, this paper puts forth a novel attention-based methodology for Resnet, intended to overcome the present constraints and attain an optimal seismic signal enhancement. Specifically, we add the convolutional block attention module (CBAM) after the convolutional layer of the residual module and add channel attention on the shortcut connections to filter out the disturbance. We replace the commonly used ReLU activation function in the network with ELU, which is better suited for suppressing seismic noise. Empirical assessments conducted on both synthetic and authentic datasets have demonstrated the efficacy of the proposed methodology in amplifying the denoising prowess of Resnet. Our proposed method remains stable even when dealing with seismic data that has complex waveforms. The findings of this investigation evince that the recommended approach furnishes a substantial augmentation in the signal-to-noise ratio (SNR), thereby facilitating the efficient and robust extraction of the underlying signal from the noisy observations. [ABSTRACT FROM AUTHOR]

The predictive skill of summer sea ice concentration (SIC) in the Arctic presents a steep decline when initialized before June, which is the so‐called spring predictability barrier for Arctic sea ice. This study explores the potential influence of surface heat flux, cloud and water vapor anomalies on monthly to seasonal predictions of Arctic SIC anomalies. The results show an enhancement in skill predicting Arctic September SIC in the models that use surface fluxes, clouds, or water vapor in combination with SIC and surface sea temperature as predictors when initialized in boreal spring. This result shows the potential to reduce the spring barrier for Arctic SIC predictions by including the surface heat budget. The enhanced predictive skill can be very likely linked to the improved representation of the thermodynamics associated with water vapor and cloudiness anomalies in spring. Plain Language Summary: Under the influence of climate change, the summer sea ice extent in the Arctic presents significant variability and thus is crucial to human activities in the Arctic. However, the predictive skill for summer sea ice in the Arctic shows a steep decline when predictions are initiated before June, which is called the spring barrier. In this study, we show that adding surface heat fluxes (net surface heat flux, net surface long wave radiation and net surface shortwave radiation), clouds or water vapor into a statistical prediction model can better represent the interactive processes at the atmosphere and ocean interface. The enhancement improves the predictive skill of summer sea ice in the Arctic and reduces the spring barrier, especially in areas of the Beaufort Sea, Chukchi Sea, and Central Arctic. Key Points: The predictive skill of summer Arctic sea ice using statistical prediction models presents a steep decline initialized before JuneThe spring barrier can be reduced, but not eliminated, by using spring surface heat fluxes in combination with sea ice concentration and sea surface temperatureThe statistical models using surface heat fluxes help to improve representation of thermodynamics associated with water vapor and cloudiness [ABSTRACT FROM AUTHOR]

Revealing the synoptic patterns related to hourly extreme precipitation (EP) is very important to deepen our recognition and understanding of EP formation. The predominant synoptic patterns associated with the summer regional hourly EP events (RHEPE) over the central‐eastern Tibetan Plateau (CETP) and Sichuan Basin (SCB) have been systematically identified. Results show the summer RHEPE over CETP and SCB are dominated by the background large‐scale circulations featured by the configuration of eastward‐extended South Asia high (SAH) and westward‐extended Western North Pacific Subtropical High (WNPSH) and their northward advance, except for that an obvious low‐level vortex imbedded in the background large‐scale circulations is mainly responsible for the summer RHEPE over SCB. The frequency and intensity of the total summer RHEPE over CETP and SCB all show an obvious increasing trend during 2000–2020, which is largely contributed by the synoptic pattern characterized by the configuration of eastward extended SAH and westward extended WNPSH. Plain Language Summary: To completely indicate the synoptic patterns leading to the summer regional hourly extreme precipitation events (RHEPE) over the central‐eastern Tibetan Plateau (CETP) and Sichuan Basin (SCB), this study has identified the dominant synoptic patterns of summer RHEPE over the two regions. Results show that the configuration of eastward extended South Asia high (SAH) and westward extended Western North Pacific Subtropical High (WNPSH) and their northward advance dominates the prime circulation patterns of summer RHEPE over CETP and SCB. However, in addition to the opposing motion of the SAH and WNPSH, a low‐level vortex imbedded in the background large‐scale circulations is mainly responsible for the summer RHEPE over SCB. The findings of this study may help us to deepen our understanding of the RHEPE formation over the two regions with complex terrain and provide a base to further improve the prediction of extreme precipitation. Key Points: Summer rainfall extremes over both central‐eastern Tibetan Plateau (CETP) and Sichuan Basin (SCB) are dominated by the combination of eastward extended SAH and westward extended Western North Pacific Subtropical HighThe summer rainfall extremes over SCB are mainly induced by a low‐level vortex imbedded in the background of large‐scale circulationsThe dominant synoptic patterns over CETP and SCB all contribute to the increasing trends of frequency and intensity of the summer regional hourly EP events [ABSTRACT FROM AUTHOR]

The Marchenko method is a data-driven way that makes it possible to calculate Green's functions from virtual points in the subsurface using the reflection data at the surface and requiring only a macro velocity model. This method requires collocated sources and receivers. However, in practice, irregular sampling of sources or receivers will cause gaps and distortions in the obtained focusing functions and Green's functions. To solve this problem, this paper proposes to integrate a sparse inversion into the iterative Marchenko scheme. Specifically, we add sparsity constraints to the Marchenko equations and apply the sparse inversion during the iterative process. To reduce the strict requirements on acquisition geometries, our work deals with the situation in which the sources are subsampled where the integrations are carried out over the receivers, while the existing point spread function method solves the situation where the receivers are subsampled. We make a step to handle both situations at the same time by integrating this method with our work because of the same iterative framework. Our new method is applied to a two-dimensional numerical example with irregularly sampled data. The result shows that it can effectively fill gaps in the obtained focusing functions and Green's functions in the Marchenko method. [ABSTRACT FROM AUTHOR]

Heavy metals in groundwater and soil are toxic to humans. An accurate risk assessment of heavy metal contamination can aid in environmental security decision making. In this study, the improved ecological risk index (RI) is used to comprehensively investigate the influence of heavy metals in soil and groundwater within electroplating factories and their surrounding regions. In the non-overlapping area, the RI of soil and groundwater is computed individually, and in the overlapping area, the greater RI of soil and groundwater is employed. Two typical electroplating factories are used to examine the heavy metal distribution pattern. The heavy metal concentrations are compared between Factory A, which is in operation, and Factory B, which is no longer in operation, in order to analyze the heavy metal concentrations and associated ecological risks. Heavy metals continue to spread horizontally and vertically after Factory B was closed. Heavy metal concentrations in groundwater surrounding Factory B are substantially greater, and the maximum concentration exists deeper than in Factory A. Because Cr, Cu, and Hg in soil contribute significantly to the RI, the primary high RI region is observed at Factory A and the region to the southwest. The RI of Factory B demonstrates a broad, moderate risk zone in the west and southwest. [ABSTRACT FROM AUTHOR]

Nanopore sequencing is promising because of its long read length and high speed. During sequencing, a strand of DNA/RNA passes through a biological nanopore, which causes the current in the pore to fluctuate. During basecalling, context-dependent current measurements are translated into the base sequence of the DNA/RNA strand. Accurate and fast basecalling is vital for downstream analyses such as genome assembly and detecting single-nucleotide polymorphisms and genomic structural variants. However, owing to the various changes in DNA/RNA molecules, noise during sequencing, and limitations of basecalling methods, accurate basecalling remains a challenge. In this paper, we propose Causalcall, which uses an end-to-end temporal convolution-based deep learning model for accurate and fast nanopore basecalling. Developed on a temporal convolutional network (TCN) and a connectionist temporal classification decoder, Causalcall directly identifies base sequences of varying lengths from current measurements in long time series. In contrast to the basecalling models using recurrent neural networks (RNNs), the convolution-based model of Causalcall can speed up basecalling by matrix computation. Experiments on multiple species have demonstrated the great potential of the TCN-based model to improve basecalling accuracy and speed when compared to an RNN-based model. Besides, experiments on genome assembly indicate the utility of Causalcall in reference-based genome assembly. [ABSTRACT FROM AUTHOR]

Abstract Due to the wide use of silver nanoparticles (AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In this study, comparative experiments were conducted to investigate the toxicological impacts of polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) with two kinds of dosing regimens, continuous and one-time pulsed dosing, in different exposure media (deionized water and XiangJiang River water). There were a number of quite different experimental results (including 100% mortality of zebrafish, decline in the activity of enzymes, and lowest number and length of adventitious roots) in the one-time pulsed dosing regimen at high PVP-AgNP concentration exposure (HOE) compared to the three other treatments. Meanwhile, we determined that the concentration of leached silver ions from PVP-AgNPs was too low to play a role in zebrafish death. Those results showed that HOE led to a range of dramatic ecosystem impacts which were more destructive than those of other treatments. Moreover, compared with the continuous dosing regimen, despite the fact that higher toxicity was observed for HOE, there was little difference in the removal of total silver from the aquatic environment for the different dosing regimens. No obvious differences in ecological impacts were observed between different water columns under low concentration exposure. Overall, this work highlighted the fact that the toxicity of AgNPs was impacted by different dosing regimens in different exposure media, which may be helpful for assessments of ecological impacts on aquatic environments. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Surface integrity determines the performance and quality of the end product. It often needs to change the input parameters, such as cutting parameter, cutting tool geometry and material, and tool coating, to obtain the best machining surface integrity. This article presents and demonstrates the effectiveness for the multi-objective optimization of cutter geometric parameters for surface integrity of milling Ti-5Al-5Mo-5V-1Cr-1Fe titanium alloy via grey relational analysis coupled with the Taguchi method, entropy weight method, and analytic hierarchy process. The main influence factors are chosen as radial rake angle, primary radial relief angle, and helix angle, while surface roughness and residual stress are taken as performance characteristics. Based on the Taguchi method, an L16 (43) orthogonal array is chosen for the experiments. The effect of cutter geometric parameters on surface roughness and residual stress is analysed by signal-to-noise ratio. Then, the multiple objectives optimization problem is successfully converted to a single-objective optimization of grey relational grade with the grey relational analysis. The weight coefficient for grey relational grade is determined by entropy weight method integrated with analytic hierarchy process. The results show that the order of importance for controllable factor to the milling surface integrity, in sequence, is radial rake angle, primary radial relief angle, and helix angle. The validation experiment verifies that the proposed optimization method has the ability to find out the optimal geometric parameters in terms of milling surface integrity. [ABSTRACT FROM AUTHOR]

Summary Melanoma patients with oncogenic BRAF V600E mutation have poor prognoses. While the role of BRAF V600E in tumorigenesis is well established, its involvement in metastasis that is clinically observed in melanoma patients remains a topic of debate. Here, we show that BRAF V600E melanoma cells have extensive invasion activity as assayed by the generation of F-actin and cortactin foci that mediate membrane protrusion, and degradation of the extracellular matrix (ECM). Inhibition of BRAF V600E blocks melanoma cell invasion. In a BRAF V600E -driven murine melanoma model or in patients’ tumor biopsies, cortactin foci decrease upon inhibitor treatment. In addition, genome-wide expression analysis shows that a number of invadopodia-related genes are downregulated after BRAF V600E inhibition. Mechanistically, BRAF V600E induces phosphorylation of cortactin and the exocyst subunit Exo70 through ERK, which regulates actin dynamics and matrix metalloprotease secretion, respectively. Our results provide support for the role of BRAF V600E in metastasis and suggest that inhibiting invasion is a potential therapeutic strategy against melanoma. [ABSTRACT FROM AUTHOR]

The mechanisms by which 2,5-hexanedione (2,5-HD) exposure adversely affects reproduction are unclear. In the present study, whole neonatal mouse ovaries were exposed to 2,5-HD in vitro and then assessed for progesterone levels to determine the effects of this compound on ovary function. Ovarian histomorphological analyses were performed to assess the effects of 2,5-HD on follicular development, and PI3K signaling pathway was evaluated to elucidate the molecular mechanisms of 2,5-HD-mediated toxicity on follicular development. The results showed that after ovarian exposure to 2,5-HD in vitro, the percentage of secondary follicles decreased, while the progesterone levels and the percentage of unhealthy follicles increased, with oocytes identified as the target of damage. The 2,5-HD treatment significantly decreased the of the gene encoding the apoptosis-related protein caspase-8, and PI3K/AKT/FOXO3 pathway signaling was also altered. Furthermore, the effects of 2,5-HD on the gene expression of the PI3K/AKT/FOXO3 and follicular development were blocked by 740Y-P (a PI3K activator), miR-214-3p was abnormally expressed, and luciferase reporter assay results demonstrated that the 3′ untranslated region of PI3K was a direct target of miR-214-3p. Overall, the results of the present study indicate that 2,5-HD exposure inhibits follicular development, and the underlying mechanism may involve interference with miR-214-3p-mediated regulation of the PI3K signaling pathway. Image 1 • 2,5-HD-exposure disrupted the follicular development in neonatal mice. • 2,5-HD-exposure interfere follicular development by affecting the expression of PI3K. • MiR-214-3p involved in regulation of 2,5-HD-exposure on follicular development. [ABSTRACT FROM AUTHOR]

Abstract: In order to obtain magnetic nanoparticles (NPs) coated with small biomolecules, histidine (His)-coated iron oxide (His-Fe3O4) and cobalt ferrite (His-CoFe2O4) with a polycrystalline structure were prepared by a simple liquid deposition method at room temperature. The growth mechanism for His-Fe3O4 and His-CoFe2O4 NPs was preliminarily explained, and their growth conditions, such as His concentrations, Co/Fe ratio, the synthesis time, were studied. The analysis of Fourier transform infrared spectra and X-ray photoelectron spectroscopy results indicated that the as-prepared particles were conjugated with the small histidine molecules. The hysteresis loops of NPs revealed their good magnetic property. L929 Cell tests indicate the good cytocompatibility of His-Fe3O4 and His-CoFe2O4 NPs, which is better than the previous prepared magnetic NPs with the polymer. [Copyright &y& Elsevier]

Abstract Cobalt nanoparticles (CoNPs) have been widely used in industry given their physical, chemical and magnetic properties; however, CoNPs may cause neurological symptoms and diseases in human, yet their mechanisms of toxicity remain unknown. Here, we used male Wistar rats to investigate differences in the toxic effects associated with CoNPs and CoCl 2. Upon exposure to CoCl 2 , and 96 nm or 123 nm CoNPs at the same concentration, the Co2+ content in CoCl 2 group was significantly higher than that in either the CoNPs groups in brain tissues and blood, but lower in liver. Significant neural damage was observed in both hippocampus and cortex of the temporal lobe. Increase malondialdehyde (MDA) content and CASPASE 9 protein level were associated both with CoCl 2 and CoNPs treatments, consistent with lipid perioxidation and apoptosis. Heme oxygenase-1 and (NF-E2) p45-related factor-2 protein levels were elevated in response to 96 nm CoNPs exposure. In PC12 cells, NRF2 downregulation led to reduced cell viability and increased apoptotic rate. In conclusion, both CoNPs and CoCl 2 cause adverse neural effects, with nanoparticles showing greater neurotoxic potency. In addition, NRF2 protects neural cells from damage induced by CoCl 2 and CoNPs by activating downstream antioxidant responses. Highlights • Both CoNPs and CoCl2 can enter central nervous system and cause toxic effects. • Both CoNPs and CoCl2 can induce apoptosis in vivo and in vitro. • Oxidative stress and apoptosis induced by CoNPs are more severethan CoCl2. • NRF2 protects neural cells from damage induced by both CoNPs and CoCl2. [ABSTRACT FROM AUTHOR]

In this study, graphene wrapped Fe-doped TiO 2 (G-TiO 2 -Fe) spheres were prepared through a simple hydrothermal process. The structural, optical and photocatalytic properties of synthesized composite were characterized by field emission scanning electron microscope (FE-SEM), X-ray diffraction ( XRD), Raman Microprobe (Raman), X-ray photoelectron spectroscopy (XPS) and UV–Vis diffuse reflectance spectrophotometer (DRS). The G-TiO 2 -Fe composite showed a significant red-shift in light response edge as compared with TiO 2 . Meanwhile, the band gap exhibited an obvious decline from 3.24 to 2.99 eV. The photocatalytic capacity of G-TiO 2 -Fe was further evaluated by methylene blue (MB) degradation experiments, and the results indicated that the optimized G-TiO 2 -Fe exhibited a remarkable increase in photocatalytic activity. The superior photocatalytic performance of the novel material could be ascribed to the synthetic effects of doped Fe and wrapped graphene shells. The unique geometrical configuration and constructive component which modified the TiO 2 electronic structure will largely improve the electron transporting efficiency and restrain the electron-hole recombination. [ABSTRACT FROM AUTHOR]

Summary: Epithelial-mesenchymal transition (EMT) is an important developmental process hijacked by cancer cells for their dissemination. Here, we show that Exo70, a component of the exocyst complex, undergoes isoform switching mediated by ESRP1, a pre-mRNA splicing factor that regulates EMT. Expression of the epithelial isoform of Exo70 affects the levels of key EMT transcriptional regulators such as Snail and ZEB2 and is sufficient to drive the transition to epithelial phenotypes. Differential Exo70 isoform expression in human tumors correlates with cancer progression, and increased expression of the epithelial isoform of Exo70 inhibits tumor metastasis in mice. At the molecular level, the mesenchymal—but not the epithelial—isoform of Exo70 interacts with the Arp2/3 complex and stimulates actin polymerization for tumor invasion. Our findings provide a mechanism by which the exocyst function and actin dynamics are modulated for EMT and tumor invasion. [Copyright &y& Elsevier]

Abstract: Silk fibroin (SF)-coated Fe3O4 nanoparticles (NPs) with good superparamagnetism were successfully prepared via a bio-mineralization process at room temperature. Two cell tests revealed that mineralized SF-coated Fe3O4 NPs presented good cytocompatibility for L929 and osteoblast cells and higher cell density after 5d with high concentrations of SF-coated Fe3O4 NPs (up to 0.5mg/mL). These resulted from SF surface coating on NPs, nano-surface morphology and iron ion release of Fe3O4 NPs. The mineralized SF-coated Fe3O4 NPs could be envisioned for various bone orthopedic and therapeutic applications, in which SF-coated NPs location is controlled through an external magnetic field to promoted bone growth. [Copyright &y& Elsevier]

Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) is characteristic of genetically extensive variation. The objective of the present study was to analyze the molecular variation and evolution of porcine reproductive and respiratory syndrome virus in China based on the complete genomic sequences of three highly pathogenic Chinese PRRSV strains isolated in 2006 and the sequences of the amplified Nsp2, ORF5 and ORF7 genes from clinical specimens during 2006–2008. Full-length genome sequencing and phylogenetic analysis showed that the three strains (JXwn06, BJsy06 and NX06) had a unique 30-amino-acid discontinuous deletion in Nsp2, and were classified into the same subgroup that consisted of the most Chinese strains isolated during 2006–2007, the pandemic period of atypical PRRS. The evolution analysis suggested that the emergence of the highly pathogenic PRRSV in China experienced a gradual variation and evolution accumulation progress from Chinese domestic virus. The variation analysis of the amplified 41 Nsp2, 59 ORF5 and 59 ORF7 genes indicated that the diversity of PRRSV strain existed in the field, and the highly pathogenic PRRSV strain with the 30-amino-acid deletion in Nsp2 was the dominating virus in China in recent years. Our data contribute to the understanding of molecular variation and epidemiology surveillance of PRRSV in China. [Copyright &y& Elsevier]

MicroRNA-150-5p (miR-150-5p) has been implicated in the progression of several cancer types, yet its specific functional role and regulatory mechanisms in bladder cancer (BC) remain largely unexplored. Our study revealed significant downregulation of miR-150-5p and upregulation of NEDD4-binding protein 2-like 1 gene (N4BP2L1) in BC tissues compared to controls using quantitative real-time polymerase chain reaction and western blot analysis, respectively. Reduced miR-150-5p expression correlated with advanced tumor stage and lymph node metastasis, while increased N4BP2L1 levels were associated with larger tumor size by the Chi-square test. Functionally, miR-150-5p exerted significant inhibitory effects on BC cell proliferation, migration, inducing G0/G1 phase arrest, and apoptosis. We confirmed N4BP2L1 as a direct target of miR-150-5p in BC cells using luciferase reporter assay. Crucially, N4BP2L1 knockdown mimicked, while overexpression counteracted the inhibitory impacts of miR-150-5p on BC cell proliferation, migration, and invasion. In addition, N4BP2L1 overexpression reversed miR-150-5p-induced alterations in CDK4, Cyclin D1, Bcl-2, PCNA, Ki-67, N-cadherin, Bad, and E-cadherin levels in BC cells. Based on these results, it can be inferred that the miR-150-5p/N4BP2L1 axis might constitute a promising candidate for therapeutic targeting in the treatment of BC., (Copyright © 2024 Copyright: © 2024 Journal of Physiological Investigation.)

Owing to their distinctive 1,3-dipolar structure, the catalytic asymmetric hydrogenation of nitrones to hydroxylamines has been a formidable and longstanding challenge, characterized by intricate enantiocontrol and susceptibility to N-O bond cleavage. In this study, the asymmetric hydrogenation and transfer hydrogenation of nitrones were accomplished with a tethered TsDPEN-derived cyclopentadienyl rhodium(III) catalyst (TsDPEN: p-toluenesulfonyl-1,2-diphenylethylene-1,2-diamine), the reaction proceeds via a novel 7-membered cyclic transition state, producing chiral hydroxylamines with up to 99 % yield and >99 % ee. The practical viability of this methodology was underscored by gram-scale catalytic reactions and subsequent transformations. Furthermore, mechanistic investigations and DFT calculations were also conducted to elucidate the origin of enantioselectivity., (© 2024 Wiley‐VCH GmbH.)

The final location of a moving object is always misremembered in the direction of the object's motion; this occurrence is called representational momentum. Three experiments were conducted to investigate the effects of phasic alertness on representational momentum by presenting a visual or auditory warning cue. In experiment 1, the mouse pointer paradigm was used, and the results showed that external warning cues increased forward displacement. Experiment 2 indicated that the effects of phasic alertness and speed of motion on representational momentum were independent. In experiment 3, the probe paradigm was used, and the results showed that external warning cues increased forward displacement as well as participants' sensitivity to the difference between the target and probe positions. These findings prove that phasic alertness boosts rather than reduces representational momentum. We propose that phasic alertness might influence representational momentum by modulating the process of executive control in the retention interval., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yan, Zeng and Liu.)

The transition-metal-catalyzed asymmetric cycloisomerization of 1,7-enynes is regarded as a formidable challenge due to the poor ability of 1,7-enynes to serve as bidentate ligands to metal. In this Letter, a highly enantioselective rhodium(I)-catalyzed Alder-ene-type cycloisomerization of 1,7-enynes is disclosed, offering an efficient method for the synthesis of a wide range of fused six-membered cyclic compounds. Furthermore, a high turnover frequency experiment and deuterium-labeling experiment were performed to give insight into this transformation.

Prostaglandins are among the most important natural isolates owing to their broad range of bioactivities and unique structures. However, current methods for the synthesis of prostaglandins suffer from low yields and lengthy steps. Here, we report a practicability-oriented synthetic strategy for the enantioselective and divergent synthesis of prostaglandins. In this approach, the multiply substituted five-membered rings in prostaglandins were constructed via the key enyne cycloisomerization with excellent selectivity (>20:1 d.r., 98% e.e.). The crucial chiral centre on the scaffold of the prostaglandins was installed using the asymmetric hydrogenation method (up to 98% yield and 98% e.e.). From our versatile common intermediates, a series of prostaglandins and related drugs could be produced in two steps, and fluprostenol could be prepared on a 20-gram scale.

Polarized exocytosis is generally considered as the multistep vesicular trafficking process in which membrane-bounded carriers are transported from the Golgi or endosomal compartments to specific sites of the plasma membrane. Polarized exocytosis in cells is achieved through the coordinated actions of membrane trafficking machinery and cytoskeleton orchestrated by signaling molecules such as the Rho family of small GTPases. Elucidating the molecular mechanisms of polarized exocytosis is essential to our understanding of a wide range of pathophysiological processes from neuronal development to tumor invasion., (Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.)

During the past 2 years, an atypical clinical outbreak, caused by a highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) with a unique 30-amino-acid deletion in its Nsp2-coding region, was pandemic in China. In this study, we generated four full-length infectious cDNA clones: a clone of the highly virulent PRRSV strain JXwn06 (pWSK-JXwn), a clone of the low-virulence PRRSV strain HB-1/3.9 (pWSK-HB-1/3.9), a chimeric clone in which the Nsp2 region containing the 30-amino-acid deletion was replaced by the corresponding region of the low-virulence PRRSV strain HB-1/3.9 (pWSK-JXwn-HB1nsp2), and a mutated HB-1/3.9 clone with the same deletion in Nsp2 as JXwn06 (pWSK-HB1-ND30). We also investigated the pathogenicities of the rescued viruses (designated RvJXwn, RvJXwn-HB1nsp2, RvHB-1/3.9, and RvHB1-ND30, respectively) in specific-pathogen-free piglets in order to determine the role of the 30-amino-acid deletion in the virulence of the highly pathogenic PRRSV. All the rescued viruses could replicate stably in MARC-145 cells. Our findings indicated that RvJXwn-HB1nsp2 retained high virulence for piglets, like RvJXwn and the parental virus JXwn06, although the survival time of piglets infected with RvJXwn-HB1nsp2 was obviously prolonged. RvHB1-ND30 exhibited low virulence for piglets, like RvHB-1/3.9 and the parental virus HB-1/3.9. Therefore, we conclude that the 30-amino-acid deletion is not related to the virulence of the highly pathogenic PRRSV emerging in China.