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Abstract The field of nickel catalysis has witnessed remarkable growth in recent years. However, the use of nickel catalysts in enantioselective C–H activation remains a daunting challenge because of their variable oxidation states, intricate coordination chemistry, and unpredictable reactivity patterns. Herein, we report an enantioselective C–H activation reaction catalyzed by commercially available and air-stable nickel(II) catalyst. Readily available and simple (S)-BINOL is used as a chiral ligand. This operationally simple protocol enables the synthesis of planar chiral metallocenes in high yields with excellent enantioselectivity through desymmetrization and kinetic resolution. Air-stable planar chiral nickelacycle intermediates are first synthesized via enantioselective C–H nickelation and shown to be possible intermediates of the reaction. Deuterium-labeling studies, alongside the characterization and transformation of chiral nickel(II) species, suggest that C–H cleavage is the enantio-determining step. Moreover, the large-scale synthesis and diverse synthetic transformations underscore the practicality of this protocol.

Based on the model of multiple random phase screens of atmospheric turbulence, the optical fields of a ring Airyprime vortex beam (RAPVB) and an Airyprime vortex beam array (APVBA) propagating in atmospheric turbulence are expressed in the form of operators. The effect of the refractive index structure constant on normalized light intensity and vortex phase for a RAPVB and an APVBA propagating in atmospheric turbulence is examined. The influences of the atmospheric propagation distance, the refractive index structure constant, and the topological charge on the target orbital angular momentum (OAM) power proportion of a RAPVB and an APVBA are analyzed. Anyway, the topological charge initially carried by a RAPVB and an APVBA can be successfully detected on the observation plane. This study indicates that a RAPVB and an APVBA with the saturated beam number are equivalent when used for analysis of target OAM power proportion. Further, this study is beneficial to the optimal design of atmospheric optical communication (AOC) systems. A RAPVB is more suitable for short distance AOC, while an APVBA is more suitable for long distance AOC.

Analytical expressions of the electric field, the centriod, the beam half width, and the linear momentum of the fractional Fourier transform (FrFT) of an Airyprime beam are derived, respectively. The relation between the centriods or the beam half widths of an Airyprime beam in the exit and the input planes of a FrFT system is also presented. The effect of the fractional order p on the FrFT of an Airyprime beam is investigated in detail and graphically presented. The cycle of the light intensity, the centriod, and the linear momentum of an Airyprime beam in the exit plane of a FrFT system versus p is 4, while the cycle of the beam half width versus p is 2. This research in the FrFT of an Airyprime beam has potential applications. First, special laser beams with different shapes can be generated by controlling p. Then, the FrFT of an Airyprime beam can be used as an optical switch due to the reversal of the positive and the negative signs of the linear momentum in the first and the last half cycle. Finally, the mirror transformation of the spatial orientation of the beam spot for the FrFT of an Airyprime can be used in optical micro-manipulation.

As the superposition of an even and odd modes constitutes an elegant Laguerre-Gaussian beam (ELGB), Airy transformation of the even mode, the odd mode, and the ELGB is studied. Analytical expressions of the even mode, the odd mode, and the ELGB in the receiver plane of Airy transformation are derived, respectively. Also, the analytical centroid and the analytical beam width for the arbitrary even mode, the arbitrary odd mode, and the arbitrary ELGB in the receiver plane of Airy transformation are concluded by numerical calculations. Moreover, the relationship of the centroids and the beam widths among the even mode, the odd mode, and the ELGB in the receiver plane of Airy transformation are presented. As typical examples, the properties of the even, the odd, and the whole beam for E01, E02, E11, and E12 are demonstrated in the receiver plane of Airy transformation. The above two subscripts correspond to the radial and the angular moduli, respectively. The effects of the transform coefficients on the normalized light intensity, the centroid, and the beam width of the even, the odd, and the whole beam for E01, E02, E11, and E12 in the receiver plane of Airy transformation are analyzed. Furthermore, the effect of the transform coefficients on the orbital angular momentum (OAM) density of E01, E02, E11, and E12 are examined. The OAM of the ELGB in the receiver plane of Airy transformation is conserved, which is not subject to influence of the transform coefficients. This study provides an optional scheme for obtaining peculiar laser beams, and also it expands applications of the even mode, the odd mode, and the ELGB.

Objectives: To determine whether glucocorticoids can improve clinical outcomes of severe fever with thrombocytopenia syndrome (SFTS) patients, and how to identify patients who may benefit from the treatment. Methods: A retrospective study was performed to include patients with confirmed SFTS from designated hospitals. The effect of glucocorticoids in reducing case fatality rate (CFR) and improving clinical recovery was evaluated by multivariate logistic regression models. Results: A total of 2478 eligible patients were analyzed, of whom 331 received glucocorticoids. An integrated parameter (L-index) based on Log10(lactate dehydrogenase*blood urea nitrogen/lymphocyte count) was constructed to discriminate disease severity. In patients with L-index >3.823 indicating severe SFTS, significantly reduced CFR was observed in patients receiving low-moderate glucocorticoid doses with ≤60 mg daily methylprednisolone or equivalent (odds ratio [OR] 0.46, 95% confidence interval [CI], 0.23-0.88), but not in patients receiving high doses. In patients with L-index ≤3.823 indicating mild SFTS, glucocorticoid treatment was significantly associated with increased CFR (OR 3.34, 95% CI, 1.35-9.51), and mainly attributable to high-dose glucocorticoids (OR 2.83, 95% CI, 1.72-4.96). Disaggregated data analysis revealed a significant effect only in patients ≤65 years old, male, and early admission within 7 days after onset, but not in their counterparts. Conclusion: Glucocorticoids are not recommended for mild patients defined by L-index

Nobiletin (NOB) is one of the major polymethoxyflavone in citrus peels, which has antioxidant activities. The purpose of this study was to investigate the effects of NOB on hypoxia-induced placental oxidative stress and its mechanism. In vitro experiments, JEG-3 hypoxic model was constructed, and treated with 100 μM NOB. In vivo experiment, pregnant rats were injected intraperitoneally with 50 mg/kg body weight NOB daily, and the placental hypoxia model was established by RUPP. NOB hampered the reducing of reducing power in hypoxic cells, promoted NADPH to provide hydrogen donors to regenerate antioxidants GPX and GSH, thereby promoting the decomposition of ROS. NOB alleviated the adverse reaction of hypoxic placental one-carbon metabolism disorder by regulating the levels of homocysteine, DNMTs and TETs. Moreover, NOB suppressed offspring brain damage induced by RUPP. Taken together, NOB attenuated hypoxia-induced placental redox perturbation and subsequent offspring brain injury by modulating one-carbon metabolism.

Freshwater fungi are an integral part of freshwater ecosystems. They promote the carbon cycle of the ecosystem by decomposing wood substrates. Menisporopsis is a fungal genus of Chaetosphaeriales in Sordariomycetes, which has been commonly collected from aquatic and marine environments. Most species of this genus are saprophytes.Here, a new freshwater hyphomycetous fungus, Menisporopsis aquatica, reported from submerged rotten wood samples collected in a stream in Zhejiang Province, south-eastern China. The new species is characterised by hyaline conidia appendiculate with 1-2 setulae at each end and synnematous conidiophores growing closely around a black central seta. Molecular phylogeny of Menisporopsis was studied using a combined two-loci dataset, including the internal transcribed spacer sequences (ITS) and the nuclear ribosomal large subunit gene sequences (nrLSU). The new species is illustrated and a synopsis of the Menisporopsis species is presented in this paper.

Objectives: Selenium deficiency can be associated with increased susceptibility to some viral infections and even more severe diseases. In this study, we aimed to examine whether this association applies to severe fever with thrombocytopenia syndrome (SFTS). Method: An observational study was conducted based on the data of 13,305 human SFTS cases reported in mainland China from 2010 to 2020. The associations among incidence, case fatality rate of SFTS, and crop selenium concentration at the county level were explored. The selenium level in a cohort of patients with SFTS was tested, and its relationship with clinical outcomes was evaluated. Results: The association between selenium-deficient crops and the incidence rate of SFTS was confirmed by multivariate Poisson analysis, with an estimated incidence rate ratio (IRR, 95% confidence interval [CI]) of 4.549 (4.215−4.916) for moderate selenium-deficient counties and 16.002 (14.706−17.431) for severe selenium-deficient counties. In addition, a higher mortality rate was also observed in severe selenium-deficient counties with an IRR of 1.409 (95% CI: 1.061−1.909). A clinical study on 120 patients with SFTS showed an association between serum selenium deficiency and severe SFTS (odds ratio, OR: 2.94; 95% CI: 1.00–8.67) or fatal SFTS (OR: 7.55; 95% CI: 1.14–50.16). Conclusion: Selenium deficiency is associated with increased susceptibility to SFTS and poor clinical outcomes.

BackgroundThis study aimed to determine the impact of co-infection of Clonorchis sinensis (CS) and hepatitis B virus (HBV) on the prognosis of patients with hepatocellular carcinoma (HCC) following hepatectomy.MethodsThe clinicopathological information of 946 patients with HCC following hepatectomy was retrospectively analyzed. The patients were divided into four groups depending on whether they had CS infection and/or HBV infection: double-negative group (infected with neither CS nor HBV), simple CS group (infected with only CS), simple HBV group (infected with only HBV), and double-positive group (co-infected with CS and HBV). Kaplan-Meier curves were used to evaluate the overall survival (OS) and recurrence-free survival (RFS), while log-rank tests were used to compare survival rates. Further, Cox regression was used to perform both univariate and multivariate survival analyses to identify variables linked to the prognosis of HCC.ResultsThe median overall survival (OS) and recurrence-free survival (RFS) in the double-positive, simple CS, simple HBV, and double-negative groups were 27 months and 9 months, 20 months and 7 months, 44 months and 12 months, and 42 months and 17 months, respectively. The double-positive group's 1-year, 3-year, and 5-year OS and RFS rates were 79.2% and 46.9%, 62.6% and 28.4%, 47.8%, and 12.2%, respectively. The simple CS group's 1-year, 3-year, and 5-year OS and RFS rates were 86.3% and 41.5%, 56.5% and 27.7%, 50.2%, and 18.5%, respectively. The simple HBV group's 1-year, 3-year, and 5-year OS and RFS rates were 89.8% and 56.0%, 72.5% and 30.5%, 63.8%, and 19.9%, respectively. The double-negative group's 1-year, 3-year, and 5-year OS and RFS rates were 91.5% and 62.3%, 76.1% and 32.9%, 64.0%, and 22.4%, respectively. Further, according to a Cox multivariate analysis, tumor size (> 5cm), Edmonson grade (III-IV), BCLC-C stage, and tumor satellite focus were independent risk factors for RFS and OS in patients with HCC.ConclusionPatients with HCC and Clonorchis sinensis infection experience a poor prognosis after hepatectomy, regardless of whether they are co-infected with HBV.

The article describes the case of a 60-year old male from Beijing, China who was diagnosed with severe fever with thrombocytopenia syndrome virus (SFTSV) infection attributed to cat contact. The patient demonstrated swollen lymph nodes in the groin area, leukopenia, thrombocytopenia and elevated levels of creatine kinase, aspartate transaminase and alanine transaminase. A field investigation suggested the role of cats in the maintenance and transmission of SFTSV within the natural environment.

As an initial channel for users learning about a mobile game, the interactive experience of the navigation interface will directly affect the first impression of the users on the game and their subsequent behaviors and willingness to use. This study aims to investigate players’ visual attention mechanisms of various interactive levels of mobile games’ interfaces under free-browsing and task-oriented conditions. Eye-tracking glasses and a questionnaire were used to measure the interactive experience of mobile games. The results show that in the free-browsing condition, the fixation count, saccade count and average saccade amplitude can be used to reflect and predict the interactive experiences of mobile games’ navigation interface; while in the task-oriented condition, the fixation count, first fixation duration, dwell time ratio and saccade count can be used to reflect and predict the interactive experience of mobile games’ navigation interface. These findings suggest that apart from the different eye movement indicators, players’ motivations should also be considered during the process of the games’ navigation interface design.

High-level user experience has become the key factor that one game can be successful in the game market. The home page of mobile games, especially the design of the navigation interface, has a significant impact on users’ initial experience, which is an important determent to users’ preferences and purchase decision. Hence, measuring users’ perceptual experiences of the navigation interface can help designers understand real demands from users. Previous studies primarily used self-report scales or interviews to measure gamers’ perceptual experiences. However, it may not reflect gamers’ real perceptions that they are feeling as most of time the feeling is short-lived and implicit. To fill this gap, the current study attempted to combine subjective evaluation with event-related potentials (ERP) to objectively measure gamers’ perceptual experience evoked by the navigation interface of the mobile game. The navigation interfaces of mobile games with low, medium, and high perceptual experience were developed and the ERP experiment was conducted to detect the differences in users’ electroencephalograph (EEG) components when subjects were exposed to the different design levels of navigation interface. The results showed that N1 reaction showed asymmetry in brain regions, and P2 and N2 showed symmetry, and relative to the navigation interface with low and medium perceptual experiences, the high level of navigation interface induced a larger amplitude of N2 in the anterior scalp and P2 in the frontal scalp. These EEG components can, therefore, be regarded as significant indicators reflecting gamers’ perceptions of the navigation interface. The findings benefit game companies of navigation interface designs.

A nanopositioner is described that has used a 6-prismatic-spherical-spherical parallel (PSS) linked compliant mechanism driven by 6 multilayered piezoelectric actuators (PZT). The nanopositioner is used for manipulating nano scale devices, fabricate nano components, or operate nano machines.