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A two‐enzyme cascade system containing ω‐transaminase (ω‐TA) and L‐threonine aldolase (L‐ThA) was reported for the synthesis of 3‐Phenylserine starting from benzylamine, and PLP was utilized as the only cofactor in these both two enzymes reaction system. Based on the transamination results, benzylamine was optimized as an advantageous amino donor as confirmed by MD simulation results. This cascade reaction system could not only facilitate the in situ removal of the co‐product benzaldehyde, enhancing the economic viability of the reaction, but also establish a novel pathway for synthesizing high‐value phenyl‐serine derivatives. In our study, nearly 95 % of benzylamine was converted, yielding over 54 % of 3‐Phenylserine under the optimized conditions cascade reaction. [ABSTRACT FROM AUTHOR]

High‐precision measurements of the magnetic field are critical to explore the near‐Mars environment. The Mars Orbiter MAGnetometer (MOMAG) is one of seven payloads on board the Tianwen‐1 orbiter. Its zero offset needs regular calibration, and the Wang‐Pan method I is applied to the MOMAG when the Tianwen‐1 orbiter is in the solar wind. The orbiter will remain out of the solar wind over tens of days each year, a method is necessary to ensure the accuracy of the zero offset during this period. Recently, a new method was proposed by Wang (2022b), https://doi.org/10.3847/1538-4357/ac822c, which is referred to as the Wang method II for ease of description. Here, we test the performance of this method using the MOMAG data measured in the Martian magnetosheath. We find that the zero offset Ow determined by the Wang method II varies around the zero offset Owp calculated by the Wang‐Pan method I using the potential Alfvénic fluctuations in the solar wind. After smoothing with a temporal window of 27 days, Ow is able to achieve an accuracy close to Owp. If the data segment has no gaps and its duration is < 27 days, the smoothed Ow might have an error >2 nT, but the error tends to be smaller if the segment's duration is longer. Our tests suggest that the Wang method II is suitable for the in‐flight calibration of the MOMAG when the Tianwen‐1 orbiter remains out of the solar wind. Key Points: We test the performance of the Wang method II in the Martian magnetosheath using the magnetic field data from the Tianwen‐1 orbiterThe zero offset determined by the Wang method II is close to that calculated by using the potential Alfvénic fluctuation in the solar windThe test results show that this method is suitable for determining the zero offset of the Tianwen‐1 orbiter in the Martian magnetosheath [ABSTRACT FROM AUTHOR]

Both hydrogen (H2) and copper ions (Cu+) can be used as anti‐cancer treatments. However, the continuous generation of H2 molecules and Cu+ in specific sites of tumors is challenging. Here we anchored Cu2+ on carbon photocatalyst (Cu@CDCN) to allow the continuous generation of H2 and hydrogen peroxide (H2O2) in tumors using the two‐electron process of visible water splitting. The photocatalytic process also generated redox‐active Cu‐carbon centers. Meanwhile, the Cu2+ residues reacted with H2O2 (the obstacle to the photocatalytic process) to accelerate the two‐electron process of water splitting and cuprous ion (Cu+) generation, in which the Cu2+ residue promoted a pro‐oxidant effect with glutathione through metal‐reducing actions. Both H2 and Cu+ induced mitochondrial dysfunction and intracellular redox homeostasis destruction, which enabled hydrogen therapy and cuproptosis to inhibit cancer cell growth and suppress tumor growth. Our research is the first attempt to integrate hydrogen therapy and cuproptosis using metal‐enhanced visible solar water splitting in nanomedicine, which may provide a safe and effective cancer treatment. [ABSTRACT FROM AUTHOR]

Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc2(WO4)3:Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back‐transfer the stored excitation energy to Ln3+ upon heating. Therefore, except routine anti‐thermal quenching, thermally enhanced 415‐fold downshifting and 405‐fold upconversion luminescence are even obtained in Sc2(WO4)3:Yb/Er, which has set a record of both the Yb3+‐Er3+ energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high‐temperature luminescence. [ABSTRACT FROM AUTHOR]

Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc2(WO4)3:Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back‐transfer the stored excitation energy to Ln3+ upon heating. Therefore, except routine anti‐thermal quenching, thermally enhanced 415‐fold downshifting and 405‐fold upconversion luminescence are even obtained in Sc2(WO4)3:Yb/Er, which has set a record of both the Yb3+‐Er3+ energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high‐temperature luminescence. [ABSTRACT FROM AUTHOR]

Different from organic dye/quantum dot possessing one luminescent center, upconversion luminescence (UCL) is actually a statistic of temporal behaviors of countless individual activators. Our experimental results have shown that the rise and decay dynamics of UCL is directly associated with the relative contribution of sensitizer‐to‐activator energy transfer and energy migration among sensitizers, which can be physically modulated by simply tuning the excitation laser. Therefore, dynamic UCL with record‐wide 20‐fold lifetime, ≈70‐fold red‐to‐green intensity ratio, and reversibly definable emission color is easily realized by just modulating the excitation laser. Moreover, this generally applicable strategy only requires a simplest‐possible UCL system whereas prevalent material engineering such as complicated composition design, sophisticated core–shell construction, or tedious chemical synthesis, is no longer needed. [ABSTRACT FROM AUTHOR]

Solar wind stream interaction regions (SIRs) and corotating interaction regions (CIRs) can cause geomagnetic storms and change energetic particle environment, ionospheric composition on Earth. Therefore advanced warning of SIRs/CIRs is vital for mitigating the effect of space weather on critical infrastructures in modern society. Recently, several solar missions, for example, Vigil mission (Luntama et al., 2020) and Solar Ring mission (Wang et al., 2020), that can be served as a space weather monitor, have been proposed. To evaluate the capabilities of these future missions of predicting SIRs/CIRs, the Solar Terrestrial Relations Observatory (STEREO‐B) spacecraft is used to investigate the correlation between SIRs/CIRs detected by STEREO‐B and Wind spacecraft. The correlation coefficients of solar wind velocity in SIRs/CIRs are significantly higher than that of magnetic field intensity or plasma density. It indicates that the velocity structure of solar wind is more persistent than magnetic field and ion density. By assuming the SIR/CIR structures are stable and ideal corotation, 58.9% of SIRs/CIRs in the STEREO‐B CIR catalog can be used to predict CIR arrival time in near‐Earth space. With increasing longitudinal and latitudinal separations between STEREO‐B and Wind, the percentage of accurately predicted CIRs decreases gradually from 100% to 20%. If the separation angle between STEREO‐B and Wind is within 30° in longitude and approximately ±5° in latitude, more than 93.2% of SIRs/CIRs can be accurately predicted several days in advance. This demonstrates that a spacecraft situated 30° trailing Earth in its orbit, can optimize our space weather‐predicting capabilities for the Earth and lessen the risk of missing or "false alarms" CIRs. Plain Language Summary: Stream interaction regions (SIRs) are formed by the interactions between the fast solar wind streams originating from coronal holes and slow solar wind streams. SIRs can corotate with the sun and they can also be called as Corotating Interaction Regions (CIRs), if those structures recur on successive solar rotations. When SIRs/CIRs reach the Earth, they may cause recurrent geomagnetic storms, alter the energetic particle environment around the Earth, and other meteorological processes in Earth's lower atmosphere, posing a threat to satellite systems, radio communications, electrical transmission, and technological critical infrastructure. As a result, the analysis and forecast of when SIRs/CIRs will hit the Earth is a critical issue in the space weather community. This study investigates the prediction ability of SIRs/CIRs with varied longitudinal and latitudinal spacecraft separations using in‐situ measurements from the Solar Terrestrial Relations Observatory (STEREO‐B) and Wind spacecraft. The statistical results reveal that the spacecraft longitudinal and latitudinal separation can have a significant impact on the accuracy of the SIRs/CIRs forecast. According to STEREO‐B in‐situ data, when the latitudinal separation is less than ±5° and the longitudinal separation is less than 30°, more than 93.2% CIR events can be well predicted in advance. Key Points: Spacecraft longitudinal and latitudinal separation can significantly affect the accurate forecast of Corotating Interaction Regions (CIRs)More than 93.2% of CIRs can be reliably predicted in advance with separations of less than 30° longitude and ±5° latitudeMost of CIRs arrived at Earth earlier than predicted, when Solar Terrestrial Relations Observatory‐B was located to the south of the Earth in the Heliocentric Earth Equatorial coordinate [ABSTRACT FROM AUTHOR]

Several hepatitis B virus (HBV) serum markers have been identified as risk factors for liver fibrosis in patients with chronic HBV infection, and several noninvasive fibrosis tests based on serum indexes are now used to identify the severity of liver fibrosis. We aimed to identify the relationship between hepatitis B core‐related antigen (HBcrAg) serum levels and liver fibrosis in treatment‐naive chronic HBV infection patients. A total of 246 treatment‐naive chronic HBV infection patients were enrolled in this study. All of the patients underwent liver biopsies at baseline. Using the METAVIR fibrosis stages, there were 15, 140, 50, 26 and 15 patients in the F0, F1, F2, F3 and F4 stages (METAVIR scoring system), respectively. The biochemical, serological and virological parameters were measured using standard laboratory procedures. The HBcrAg serum levels of the patients were examined via ELISA. HBcrAg serum levels of F2, F3 and F4 stage patients were significantly higher than those of nonsignificant liver fibrosis patients (METAVIR F0‐F1), but there were no significant differences among F2, F3 and F4 stage patients. Serum HBcrAg (OR, 2.18; 95% confidence interval [CI], 1.51–3.16), albumin (ALB) (OR, 0.60; 95% CI, 0.41–0.87), prothrombin activity (PTA) (OR, 0.58; 95% CI, 0.40–0.83) and platelet (PLT) counts (OR, 0.38; 95% CI, 0.25–0.57) were associated with significant liver fibrosis (METAVIR F2‐F4). The serum HBcrAg value enabled the correct identification of patients with significant fibrosis, with an area under the receiver operating characteristic curve of 0.81 (95% CI, 0.75–0.88). The APRI, FIB‐4 index and ALBI score can identify significant liver fibrosis with an area under the ROC curve of 0.74 (95% CI, 0.66–0.81), 0.73 (95% CI, 0.65–0.80) and 0.63 (95% CI, 0.55–0.72), respectively. Compared with these three indexes, the accuracy rate of diagnosis of significant fibrosis based on HBcrAg was higher than that of the FIB‐4 index (p = 0.0479) and ALBI score (p = 0.0030). HBcrAg, ALB, PTA serum levels and PLT counts were associated with significant liver fibrosis in treatment‐naive chronic HBV infection patients. HBcrAg serum levels enabled the correct identification of patients with significant fibrosis (METAVIR F2–F4), and HBcrAg was more effective than the FIB‐4 index and ALBI score. [ABSTRACT FROM AUTHOR]

Ene reductases (ERs) are attractive biocatalysts in terms of their high enantioselectivity and expanded substrate scope. Recent works have proved that synthetic nicotinamide coenzyme biomimetics (NCBs) can be used as easily accessible alternatives to natural cofactors in ER‐catalyzed reactions. However, the structure‐reactivity relationships between NCBs and ERs and influence factors are still poorly understood. In this study, a series of C‐5 methyl modified NCBs were synthesized and tested in the PETNR‐catalyzed asymmetric reductions. The physicochemical properties of these NCBs including electrochemical properties, stability, and kinetic behavior were studied in detail. The results showed that hydrophobic interaction caused by the introduced methyl group contributed to the stabilization of binding conformation in enzyme active site, resulting in comparable catalytic activity with that of NADPH. Molecular dynamics and steered molecular dynamics simulations were further performed to explain the binding mechanism between PETNR and NCBs, which revealed that stable catalytic conformation, appropriate donor‐acceptor distance and angle, as well as free dissociation energy are important factors affecting the activity of NCBs. [ABSTRACT FROM AUTHOR]

Utilizing hydrogen energy produced by water electrolysis is conducive to carbon neutrality from a technological point of view. However, this perspective is restrained by the high electricity cost in commercial development. Powering electrochemical reactions by renewable electricity converted from distributed mechanical energy can lead to commercial electric energy saving and cost reduction. In this work, a self‐powered electrochemical system (SPECS) is proposed for the conversion from blue energy of ocean waves to green energy via hydrogen fuel. This system consists of triboelectric nanogenerator (TENG) devices and an electrolyzer, where the TENG devices serve as ocean wave energy harvesters for electricity generation, while the seawater‐containing electrolyzer is employed for hydrogen generation. After power management on the output of the TENGs and electrochemical reaction optimization, the system can generate hydrogen at a rate of 814.8 µL m‐2 d‐1 and a Faraday efficiency of 69.1% under ideal operation conditions, demonstrating the practical potential of the constructed system toward carbon neutralization. [ABSTRACT FROM AUTHOR]

Hybrid at either the mechanism or the device level can lead to a hybridization effect of the kinetics and electrochemical characteristic of a supercapacitor (SC). Herein, a heterostructured NiCo2S4/CoxNi1‐x(OH)2 battery‐like cathode material was designed, with which the obtained sample accomplished the combination of excellent electronic and ionic conductivity so as to realize an enhanced faradaic redox storage process. Besides, a SC‐type highly capacitive anode material of a N and S co‐doped porous carbon nanosheets (ACNS) was also fabricated, which exhibits great advantages in terms of its enlarged specific surface area, the ease of introducing pseudocapacitive reactions, and its physical structure. These features directly lead to significant improvements in the electric double‐layer capacitor (EDLC)‐type electrochemical properties of the carbon anode. The combination of an EDLC‐type carbon anode with the redox‐reaction‐type cathode in a full cell device could potentially lead to a charge storage process that simultaneously integrates the electrophysical and electrochemical processes. For these reasons, the obtained solid‐state hybrid SC delivers a wide voltage window of 1.6 V, a high specific capacity of 121.3 C g−1, and enhanced energy/power densities of 26.1 Wh kg−1/11 kW kg−1. The as‐assembled device can maintain a high and stable capacity retention of 89.1 % for over 10 000 cycles. The developed hybrid assembly strategy and the electrode combination may provide design guidelines for designing other high‐energy hybrid SCs. [ABSTRACT FROM AUTHOR]

Stream interaction regions (SIRs) are important sources of geomagnetic storms. In this work, we first extend the end time of the widely used SIR catalog developed by Jian et al. (2006, https://doi.org/10.1007/s11207-006-0132-3), which covered the period from 1995 to 2009, to the end of 2016. Based on this extended SIR catalog, the geoeffectiveness of SIRs is discussed in detail. It was found that 52% of the SIRs caused geomagnetic storms with Dstmin ≤−30 nT, but only 3% of them caused intense geomagnetic storms with Dstmin ≤−100 nT. Furthermore, we found that 10 of the intense geomagnetic storms caused by SIRs were associated with complex structures due to interactions between SIRs and interplanetary coronal mass ejections (ICMEs). In such a structure, an ICME is embedded in the SIR and located between the slow and fast solar wind streams. In addition, we found that the geoeffectiveness of SIRs interacting with ICMEs is enhanced. The possibility of SIR‐ICME interaction structures causing geomagnetic storms is markedly higher than that of isolated SIRs or isolated ICMEs. In particular, the geoeffectiveness of SIR‐ICME interaction structures is similar to that of the Shock‐ICME interaction structures, which have been demonstrated to be the main causes of geomagnetic storms. Key Points: The near‐Earth SIR catalog developed by Jian et al. (2006) has been extended to the end of 2016Fifty‐two percent of the SIRs caused geomagnetic storms, but only 3% of the SIRs caused intense geomagnetic stormsSIRs that interact with ICMEs exhibit significantly enhanced geoeffectiveness [ABSTRACT FROM AUTHOR]

Abstract: Magnetic flux rope (MFR) is the core structure of the greatest eruptions, that is, the coronal mass ejections (CMEs), on the Sun, and magnetic clouds are posteruption MFRs in interplanetary space. There is a strong debate about whether or not a MFR exists prior to a CME and how the MFR forms/grows through magnetic reconnection during the eruption. Here we report a rare event, in which a magnetic cloud was observed sequentially by four spacecraft near Mercury, Venus, Earth, and Mars, respectively. With the aids of a uniform‐twist flux rope model and a newly developed method that can recover a shock‐compressed structure, we find that the axial magnetic flux and helicity of the magnetic cloud decreased when it propagated outward but the twist increased. Our analysis suggests that the “pancaking” effect and “erosion” effect may jointly cause such variations. The significance of the pancaking effect is difficult to be estimated, but the signature of the erosion can be found as the imbalance of the azimuthal flux of the cloud. The latter implies that the magnetic cloud was eroded significantly leaving its inner core exposed to the solar wind at far distance. The increase of the twist together with the presence of the erosion effect suggests that the posteruption MFR may have a high‐twist core enveloped by a less‐twisted outer shell. These results pose a great challenge to the current understanding on the solar eruptions as well as the formation and instability of MFRs. [ABSTRACT FROM AUTHOR]

Novel blue-green emitting Ce3+- and Tb3+-activated K2CaP2O7 ( KCPO) luminescent materials were synthesized via a solid-state reaction method. X-ray diffraction, luminescence spectroscopy, decay time, and fluorescent thermal stability tests have been used to characterize the prepared samples. The KCPO:Ce3+,Tb3+ luminescence spectra show broad band of Ce3+ ions and characteristic line of Tb3+ ion transition (5D4-7F5). The color variation in the light emitting from blue to green under UV excitation can be obtained by tailoring the Tb3+ content in KCPO:Ce3+. Besides, Ce3+ ions obviously intensify Tb3+ ion emission through an effective energy transfer process, which was confirmed from decay curves. The energy transfer efficiency was determined to be 82.51%. A resonant type mechanism via the dipole-quadrupole interaction can be proposed for energy transfer. As a whole, the KCPO:Ce3+,Tb3+ phosphor exhibits excellent performance in the range from 77 to 673 K, indicating the phosphors are highly potential candidates for solid-state lighting. [ABSTRACT FROM AUTHOR]

Electrospinning, as a novel nontextile filament technology, is an important method to prepare continuous nanofibers and has shown its remarkable advantages, such as a broadly applicable material system, controllable fiber size and structure, and simple process. Electrospun nanofiber membranes prepared by electrospinning have shown promising applications in many fields, such as supercapacitors, lithium-ion batteries, and sodium-ion batteries, owing to their large specific surface area and adjustable network pore structure. The principle of electrospinning and key points relevant to its usage in the preparation of high-performance electrochemical energy storage materials are reviewed herein based on recent publications, particularly focusing on research progress of relative materials. Also, this review describes a distinctive conclusion and perspective on the future challenges and opportunities in electrospun nanomaterials. [ABSTRACT FROM AUTHOR]

A series of color tunable Tb3+- and Eu3+-activated Sr2P2O7 phosphors were synthesized by a traditional solid-state reaction method in air atmosphere. The crystal structure, photoluminescence ( PL) properties, energy transfer, thermal stability, and luminous efficiency were investigated. A series of characteristic emission of Tb3+ and Eu3+ were observed in the PL spectra and the variation in the emission intensities of the three emission peaks at around 416 nm (blue), 545 nm (green), and 593 nm (orange-red) induced the multicolor emission evolution by tuning the Tb3+/Eu3+ content ratio. The energy-transfer mechanism from Tb3+ to Eu3+ ion was determined to be dipole-dipole interaction, and the energy-transfer efficiency was about 90%. The novel phosphors have excellent thermal stability in the temperature range of 77-473 K and the Commission International De L'Eclairage 1931 chromaticity coordinates of Sr2P2O7: Tb3+, Eu3+ (λex = 378 nm) move toward the ideal white light coordinates. [ABSTRACT FROM AUTHOR]

Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc2(WO4)3:Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back‐transfer the stored excitation energy to Ln3+ upon heating. Therefore, except routine anti‐thermal quenching, thermally enhanced 415‐fold downshifting and 405‐fold upconversion luminescence are even obtained in Sc2(WO4)3:Yb/Er, which has set a record of both the Yb3+‐Er3+ energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high‐temperature luminescence. [ABSTRACT FROM AUTHOR]

Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc2(WO4)3:Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back‐transfer the stored excitation energy to Ln3+ upon heating. Therefore, except routine anti‐thermal quenching, thermally enhanced 415‐fold downshifting and 405‐fold upconversion luminescence are even obtained in Sc2(WO4)3:Yb/Er, which has set a record of both the Yb3+‐Er3+ energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high‐temperature luminescence. [ABSTRACT FROM AUTHOR]