Defect compensation and intervalence charge transfer state-based Pr3+-doped niobate antithermal quenching phosphors.

Herein, a scheme of Sr2+/Ca2+ ion substitution was employed to simultaneously regulate the defect and intervalence charge transfer (IVCT) state of Sr2-xCaxNb2O7:Pr3+ phosphors, resulting in a dual-modulation strategy for enhancing phosphor thermal stability.

Enhanced thermally stable performance of Pr3+-doped vanadate phosphor by inhibiting the intervalence charge transfer quenching channel.

Praseodymium (Pr3+) ion and the transition metal vanadium (V5+) ion with d0 electronic configuration can form an intervalence charge transfer (IVCT) band, which can function both as a compensatory channel for its red emission and as a quenching channel, thus affecting the luminescence thermal stability of the phosphors. Research studies reveal that the emission of Pr3+ in the YVO4 matrix can be quenched by the IVCT mechanism, thereby limiting the application of phosphors. As such, the present contribution is based on the solid solution replacement strategy to inhibit the constitutent of the IVCT quenching channel and thus improve thermal stability. Therefore, phosphonium (P5+) with a valence state matching V5+ and a similar ion radius was selected for the V/P substitution. It lacks a d0 electron configuration, preventing the formation of an IVCT band with Pr3+ and thereby inhibiting the construction of the quenching channels to enhance thermal stability. While the empirical formula of IVCT indicates a decrease in the IVCT energy level from 3.32438 to 3.06251 eV upon the introduction of P5+, the PLE spectra demonstrate a sharp reduction in IVCT intensity, i.e., weakening of the quenching channel. The thermal stability of the phosphors at different excitation locations was enhanced with the rise of P5+ concentration. When excited at the 3P2 level, the Y0.995PO4:0.5%Pr3+ phosphor demonstrated highly stable red emission from 303 to 523 K, with a luminescence integrated intensity ranging from 95.5% to 105.3% compared to that at 303 K. This research provides a novel approach for inhibiting the IVCT quenching channel and broadens the commercial value of YVO4:Pr3+ phosphor for various applications.

Construction of thermally stable Tb3+-activated green-emitting phosphors: dual driving strategy of doping concentration and excitation wavelength.

The realization of thermally stable Tb3+-doped green emission at high temperatures in solid-state lighting is still a crucial challenge. Nevertheless, the study on modulating the thermally stable luminescence at high temperatures is seldom reported. The position of the intervalence charge transfer (IVCT) energy level is used to systematically investigate the thermal quenching performance of Tb3+-activated green-emitting phosphors with varying concentration gradients of Gd1-xTaO4:xTb3+ (x = 0.1%, 0.5%, and 2%) in this study. The IVCT energy levels were determined according to the empirical formula to show a decreasing trend, consistent with the position of the IVCT energy levels measured in the excitation and diffuse reflectance spectra. Moreover, the thermal quenching performance of different wavelength excitation positions (host absorption, 4f-5d of Tb3+, and Tb3+-Ta5+ IVCT band) is quite different. The modulation of thermal quenching performance among distinct phosphors when subjected to host excitation or IVCT excitation can be elucidated through optimal positions within the energy levels associated with IVCT. The diverse concentration gradient samples exhibit varying degrees of thermal quenching performance in the variable-temperature spectra. The fluorescence lifetimes of the samples are generally comparable but slightly lower. The quantum efficiency rapidly improves as the Tb concentration increases. The underlying mechanism governing this phenomenon is elucidated by constructing a model that encapsulates the interplay between the compensating and quenching channels, in addition to the energy conversion of Tb3+ into Gd3+. The abovementioned results indicate that the dual driving scheme of the doping concentration and excitation wavelength is an effective means to regulate the thermal quenching performance of Tb-activated green-emitting tantalate phosphors.

Comparative study of electro-Fenton and photoelectro-Fenton processes using a novel photocatalytic fuel cell electro-Fenton system with g-C3 N4 @N-TiO2 and Ag/CNT@CF as electrodes.

In this study, a novel photocatalytic fuel cell electro-Fenton (PFC-EF) system was constructed using g-C3 N4 @N-TNA and Ag/CNT@CF as electrodes. The composition, structure, and morphology of the electrodes were obtained. The g-C3 N4 @N-TNA, with its 2.37 eV band gap and 100 mV photovoltage, has excellent excitation properties for sunlight. Ag/CNT@CF with abundant pores, CNT 3D nanostructures, and Ag crystals on the surface can improve the electro-Fenton efficiency. A comparative study of rhodamine B (RhB) degradation was performed in this system. It has been shown that electric fields can greatly enhance the oxidation efficiency of both anode photocatalysis and the cathode electro-Fenton process. Under optimal conditions, RhB can be completely removed by the photoelectro-Fenton (PEF) process. The energy consumption of the PEF system was obtained. The electrical energy per order (EE/O) is only 9.2 kWh/m3 ·order, which is only 16.5% of EF and 2.2% of PFC-EF system. The mineralization current efficiency (MCE) of the PEF system reached 93.3% for a 2-h reaction. Therefore, the PEF system has the advantage of saving energy. The kinetic analysis shows that the RhB removal follows a first-order kinetic law, and the reaction rate constant reaches 0.1304 min-1 , which is approximately 5.2 times larger and 4.0 times larger than the electro-Fenton and PFC-EF processes, respectively. RhB removal is a coupling multimechanism in which an electric field enhances photoelectron migration, Ag loading improves H2 O2 generation, UV light coupled with H2 O2 promotes hydroxyl radical (Ù OH) generation, and the nanoconfinement effect of CNTs promotes Ù OH accumulation in favor of RhB degradation. PRACTITIONER POINTS: Novel efficiency photocatalytic fuel cell electro-Fenton system was constructed. The electric field greatly enhances the photocatalytic fuel cell electro-Fenton system. Multiple coupling mechanisms of UV/H2O2, UV/Fenton and photo-electro-Fenton have been revealed.

N-doped graphene aerogel cathode with internal aeration for enhanced degradation of p-nitrophenol by electro-Fenton process.

A columnar N-doped graphene aerogel (NGA) was successfully fabricated by one-step hydrothermal synthesis using L-hydroxyproline as reductant, N-doping, and swelling agent, and it was used as the cathode with internal aeration mode for the electro-Fenton degradation of p-nitrophenol. Owing to the stable solid-liquid-gas three-phase interface, more active defects, and modulated nitrogen dopants, the NGA cathode exhibited enhanced electrocatalytic activity. H2O2 could be continuously electro-generated via a two-electron oxygen reduction, and the yield of H2O2 was 153.3 mg·L-1·h-1 with the low electric energy consumption of 15.3 kWh kg-1. Simultaneously, the NGA cathode had better charge transfer capability with N-doping, which was conducive to the conversion of Fe3+/Fe2+. Under the optimal condition, nearly 100% removal of p-nitrophenol and 84% removal of TOC were obtained within 60 and 120 min, respectively. The NGA cathode also presented good stability and versatile applicability in different water matrices. Therefore, the NGA is a cost-effective cathode material in electro-Fenton system with adequate activity and reuse stabilization.

Encryption chain based on measurement result and its applications on semi-quantum key distribution protocol.

This study proposes a new encoding method, also known as an encryption chain based on the measurement result. Then, using the encryption chain to propose a unitary-operation-based semi-quantum key distribution protocol (SQKD) protocol. In the existing SQKD protocols, semi-quantum environments adopt a round-trip transmission strategy. In round-trip transmission, the classical participant must resend the received photons to the quantum participant after implementing local operations. Therefore, round-trip transmissions are vulnerable to Trojan horse attacks. Hence, the classical participant must be equipped with a photon number splitter and an optical wavelength filter device against Trojan horse attacks. This is illogical for semi-quantum environments because the burden on the classical participant is significantly increased as it involves the prevention of Trojan horse attacks. The proposed SQKD protocol is congenitally immune to Trojan horse attacks and involves no extra hardware because it is designed based on a one-way transmission as opposed to a round-trip transmission. When compared to the existing SQKD protocols, the proposed SQKD protocol provides the best qubit efficiency, and classical participants only require two quantum capabilities, which enhance its practicability. Moreover, the proposed SQKD protocol is free from collective attacks, Trojan horse attacks, and intercept-resend attacks. Thus, the proposed scheme is more efficient and practical than the existing SQKD protocols.

SIN3-HDAC complex-associated factor, a chromatin remodelling gene located in the 12p amplicon, is a potential germ cell tumour-specific oncogene.

A genetic hallmark of malignant germ cell tumours (GCTs) is isochromosome 12p, but oncogenes located in 12p that are specifically expressed in GCT have not yet been identified. SIN3-HDAC complex-associated factor (SINHCAF) is a subunit of the Sin3/histone deacetylase (HDAC) complex, and it defines a Sin3a-Hdac complex variant that is required for the self-renewal of mouse embryonic stem cells. This study demonstrated that SINHCAF is expressed in a vast majority of malignant GCTs and is rarely expressed in somatic malignancy. Fluorescence in situ hybridisation revealed SINHCAF amplification in malignant GCTs. SINHCAF silencing using shRNA reduced anchorage-dependent cell proliferation and tumoursphere formation and inhibited tumour cell migration and invasion in GCT cell lines. Moreover, in the GCT cell line NTERA2/D1, SINHCAF silencing inhibited the expression of genes associated with embryonic stem cells and induced the expression of genes associated with neuronal and white fat cell differentiation. Compared with somatic cell lines, GCT cell lines were more susceptible to HDAC inhibitor treatment. Thus, we identified SINHCAF to be a potential oncogene located in the amplicon of chromosome 12p and showed that SINHCAF was specifically expressed in malignant GCTs. HDAC inhibitor treatment may counteract the oncogenic activity of SINHCAF and is a promising therapeutic approach for GCTs. © 2022 The Pathological Society of Great Britain and Ireland.

Authenticated Semi-Quantum Key Distribution Protocol Based on W States.

In 2019, Wen et al. proposed authenticated semi-quantum key distribution (ASQKD) for identity and message using the teleportation of W states and GHZ-like states without pre-shared keys. However, the ASQKD protocol presents a vital issue in the teleportation of W states owing to its inappropriate design. Bob recovers the teleported W states without obtaining the position of the corresponding photons and then returns the recovered photons back to Alice. Hence, the teleportation of W states in Wen et al.'s ASQKD protocol was malfunctioning. Moreover, Wen et al.'s ASQKD protocol requires quantum memory, which strongly disobeys the definition of semi-quantum proposed by Boyer et al. Therefore, in this study, we discover the flaws of Wen et al.'s ASQKD protocol and propose an authenticated semi-quantum key distribution protocol. When compared to Wen et al.'s ASQKD protocol, the proposed ASQKD protocol has the following advantages: legal semi-quantum environment (i.e., does not require quantum memory), reduced quantum hardware requirement (i.e., based only on W states), does not involve classical cryptography (i.e., the hash function), and provided 1.6 times higher qubit efficiency.

Cryptanalysis of a Semi-Quantum Bi-Signature Scheme Based on W States.

Recently, Zhao et al. proposed a semi-quantum bi-signature (SQBS) scheme based on W states with two quantum signers and just one classical verifier. In this study, we highlight three security issues with Zhao et al.'s SQBS scheme. In Zhao et al.'s SQBS protocol, an insider attacker can perform an impersonation attack in the verification phase and an impersonation attack in the signature phase to capture the private key. In addition, an eavesdropper can perform a man-in-the-middle attack to obtain all of the signer's secret information. All of the above three attacks can pass the eavesdropping check. Without considering these security issues, the SQBS protocol could fail to ensure the signer's secret information.

Lightweight mediated semi-quantum key distribution protocol with a dishonest third party based on Bell states.

The mediated semi-quantum key distribution (MSQKD) protocol is an important research issue that lets two classical participants share secret keys securely between each other with the help of a third party (TP). However, in the existing MSQKD protocols, there are two improvable issues, namely (1) the classical participants must be equipped with expensive detectors to avoid Trojan horse attacks and (2) the trustworthiness level of TP must be honest. To the best of our knowledge, none of the existing MSQKD protocols can resolve both these issues. Therefore, this study takes Bell states as the quantum resource to propose a MSQKD protocol, in which the classical participants do not need a Trojan horse detector and the TP is dishonest. Furthermore, the proposed protocol is shown to be secure against well-known attacks and the classical participants only need two quantum capabilities. Therefore, in comparison to the existing MSQKD protocols, the proposed protocol is better practical.

Structure-guided antibody cocktail for prevention and treatment of COVID-19.

Development of effective therapeutics for mitigating the COVID-19 pandemic is a pressing global need. Neutralizing antibodies are known to be effective antivirals, as they can be rapidly deployed to prevent disease progression and can accelerate patient recovery without the need for fully developed host immunity. Here, we report the generation and characterization of a series of chimeric antibodies against the receptor-binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Some of these antibodies exhibit exceptionally potent neutralization activities in vitro and in vivo, and the most potent of our antibodies target three distinct non-overlapping epitopes within the RBD. Cryo-electron microscopy analyses of two highly potent antibodies in complex with the SARS-CoV-2 spike protein suggested they may be particularly useful when combined in a cocktail therapy. The efficacy of this antibody cocktail was confirmed in SARS-CoV-2-infected mouse and hamster models as prophylactic and post-infection treatments. With the emergence of more contagious variants of SARS-CoV-2, cocktail antibody therapies hold great promise to control disease and prevent drug resistance.

Synthesis, Characterization, and Catalytic Application of Palladium Complexes Containing Indolyl-NNN-Type Ligands.

In this study, a series of N-heterocyclic indolyl ligand precursors 2-Py-Py-IndH, 2-Py-Pz-IndH, 2-Py-7-Py-IndH, 2-Py-7-Pz-IndH, and 2-Ox-7-Py-IndH (L1H-L5H) were prepared. The treatment of ligand precursors with 1 equivalent of palladium acetate affords palladium complexes 1-5. All ligand precursors and palladium complexes were characterized by NMR spectroscopy and elemental analysis. The molecular structures of complexes 3 and 5 were determined by single crystal X-ray diffraction techniques. The application of those palladium complexes 1-5 to the Suzuki reaction with aryl halide substrates was examined.

Paenibacillus glycinis sp. nov., an Endophytic Bacterium Isolated from the Nodules of Soybean (Glycine max (L.) Merr).

A Gram-negative-staining, endospore-forming, rod-shaped bacterium, designated T1T, was isolated from root nodules of soybean (Glycine max (L.) Merr) in Heilongjiang Province of China. The isolate was identified as a member of the genus Paenibacillus based on phenotypic and phylogenetic characteristics. The 16S rRNA sequence was closely related to that of Paenibacillus sacheonensis SY01T with a similarity of 98.4%. Average nucleotide identity and in silico DNA-DNA hybridization values between strain T1T and P. sacheonensis DSM 23054 T were 81.4% and 25.4%, respectively. The DNA G + C content of strain T1T was 58.2 mol%. meso-Diaminopimelic acid was detected in the cell-wall peptidoglycan. The major cellular fatty acids were anteiso-C15:0, iso-C16:0 and iso-C15:0. The predominant respiratory quinone was MK-7. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified phospholipids, four unidentified aminophospholipids, an unidentified glycolipid and an unidentified lipid. Based on these results, T1T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus glycinis sp. nov. is proposed. The type strain is T1T (= CGMCC 1.18563 = KCTC43227).

Chinese Traditional Medicine NiuBeiXiaoHe (NBXH) Extracts Have the Function of Antituberculosis and Immune Recovery in BALB/c Mice.

BACKGROUND: The Traditional Chinese Medicine NiuBeiXiaoHe (NBXH) is a valid antituberculosis (TB) prescription from the experience of clinical practice. However, the mechanism of NBXH extracts' immunotherapy has been poorly understood. Herein, the immunotherapeutic efficacy and the differentially expressed (DE) genes of NBXH extracts were evaluated and identified in BALB/c mice. METHODS: The total RNA was extracted from peripheral blood mononuclear cells, and the DE genes were identified by gene chip. The enrichment and signaling pathway analyses were performed using Gene Ontology (GO) and KEGG database. RESULTS: It was shown that the treatment of NBXH extracts (high dose) significantly reduced mycobacteria loads and histopathological lesions in mice infected by Mycobacterium tuberculosis and resulted in 3,454 DE upregulated genes and 3,594 downregulated DE genes. Furthermore, NBXH extracts killed mycobacteria by inhibiting the supply of necessary ingredients for their growth and proliferation. They restored the disordered immune microenvironments by up- or downregulating immune and inflammation-related pathways. CONCLUSIONS: Taken together, NBXH extracts not only efficiently decreased the mycobacteria loads but also balanced the immune disorders in mice. These new findings provide a fresh perspective for elucidating the immunotherapeutic mechanism of NBXH extracts and pointed out the direction for improving the treatment efficacy of NBXH extracts.

Removal of aniline from water by an Fe(II)-nano-Fe3O4@PAC heterogeneous catalyst in a Fenton-like process.

Aniline is a toxic chemical, and in many industries it is degraded by Fenton processes. In this study, an Fe(II)-nano-Fe3O4@PAC heterogeneous Fenton catalyst (MFC) was prepared with a coprecipitation and impregnation method, which is simple, efficient and cost effective. The results of the magnetic performance tests showed that the MFC has typical ferromagnetism properties. Nano-Fe3O4 was found both on the surface and inside the pores of the powdered activated carbon (PAC). MFC was found to be an efficient catalyst in the Fenton-like process for aniline degradation. The optimal conditions were obtained by the orthogonal experimental method. The results showed that under the optimal conditions (pH = 3.00, temperature = 20°C, concentration of MFC = 1.0 g/L, concentration of H2O2 = 0.27 g/L), the 5 mg/L aniline solution degradation ratio reached 91.2% and the mineralization ratio reached 75.77% in 30 min. In addition, kinetics studies indicated that the aniline degradation process follows a pseudo-first-order kinetics model. No refractory intermediate such as azobenzene, was found during the reaction. The pH value is an important factor in aniline solution degradation. This result indicates that in addition to the surface catalytic reaction, the Fenton reaction also occurs in solution. Fe2+/Fe3+ on the MFC surface and Fe2+/Fe3+ in solution both affect aniline degradation. This catalyst has the advantage of being easily magnetically separated from the aqueous phase. It has useful application prospects in solving organic industrial wastewater pollutions in developing countries because of its cost-effectiveness.

Impact of Soybean Nodulation Phenotypes and Nitrogen Fertilizer Levels on the Rhizosphere Bacterial Community.

The effects of nodulation properties of legumes on the rhizosphere bacterial community are still not clear. To determine the effects of nodulation phenotypes on bacterial communities in the rhizosphere of soybean plants, we performed high-throughput sequencing of the 16S rRNA gene to estimate the rhizosphere bacterial community of three soybean lines with different nodulation phenotypes grown in soil supplied with different levels of N fertilizer. The results revealed that both the soybean nodulation phenotypes and the N levels affected the rhizosphere bacteria community, but the nodulation phenotypes contributed more than the N-supply. The diversity of bacteria was decreased in the rhizosphere of super-nodulating phenotype. The response of rhizosphere bacterial communities to the soil available nitrogen (AN) concentrations was different than the response with the three nodulation phenotypes of soybean which was more stable in the wild-type (Nod+) soybean samples than that in the mutant samples (Nod- and Nod++). Bradyrhizobium in the rhizosphere was positively correlated with nodule number and negatively correlated to AN in the soil, while Burkholderia and Dyella were positively correlated with nodule biomass and nitrogenase activity. These results demonstrated that the nodulation phenotype of soybean affects the rhizosphere microbiome.

Investigation of Atyp.C using UF-5000 flow cytometer in patients with a suspected diagnosis of urothelial carcinoma: a single-center study.

BACKGROUND: This study evaluated the predictive power of Atyp.C (a parameter of UF-5000 flow cytometer) for patients with a suspected diagnosis of urothelial carcinoma. METHODS: We analyzed 163 urine specimens from 128 patients with suspected urothelial carcinoma using a fully automated fluorescence flow cytometry analyzer (UF-5000) and evaluated its performance on identifying atypical/malignant urothelial cells. From January 1, 2019 to April 4, 2019, all consecutive specimens for urinary cytopathology were enrolled. RESULTS: Of the specimens with urinary cytopathology, 67 specimens (41.1%) revealed abnormal findings in cytology analysis. Among them, 20 specimens (12.3%) were diagnosed as atypical urothelial cells, 26 specimens (16.0%) as suspicious for malignancy (S-malignancy), and 21 specimens (12.9%) as confirmed malignancy. The UF-5000 findings were positive in 59 specimens (36.2%); therefore, the agreement with cytopathology was 73.0%. Using follow-up histologic diagnosis of urothelial carcinoma with or without urinary tract cytology (UTCy) as a reference standard (suspicious and confirmed malignancy were the positive criteria for UTCy), the sensitivity was 59.0%, specificity was 82.1%, positive predictive value was 75.0%, negative predictive value was 68.8%, and the agreement was 71.1%. CONCLUSIONS: It is worth knowing and reporting that the Atyp.C assay may be used as an accessory test for patients with suspected urothelial carcinoma, based on its ability to identify high-risk patients who might need closer follow-up or additional medical treatment.

Fabrication of a double-layer membrane cathode based on modified carbon nanotubes for the sequential electro-Fenton oxidation of p-nitrophenol.

To improve the electrocatalytic efficiency of the cathode and provide a wider pH range in the electro-Fenton process, N-doped multi-walled carbon nanotubes (NCNTs) and ferrous ion complexed with carboxylated carbon nanotubes (CNT-COOFe2+) were used to fabricate the diffusion layer and catalyst layer of a membrane cathode, respectively. The morphology, structure, and composition of CNT-COOFe2+ were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The oxygen reduction performance of NCNT was evaluated using cyclic voltammetry (CV) and the rotating disk electrode technique (RDE). In addition, a potential application of the cathode in sequential electro-Fenton degradation of p-nitrophenol (p-NP) was investigated. The results revealed that iron was successfully doped on the carboxylated carbon nanotubes in ionic complexation form and the content of iron atoms in CNT-COOFe2+ was 2.65%. Furthermore, the defects on the tube walls provided more reactive sites for the electro-Fenton process. A combination of CV and RDE data indicated that NCNT had better electrocatalytic H2O2 generation activity with a more positive onset potential and higher cathodic peak current response than CNT. A p-NP removal rate of 96.04% was achieved within 120 min, and a mineralization efficiency of 80.26% was obtained at 180 min in the sequential electro-Fenton process at a cathodic potential of - 0.7 V vs SCE and neutral pH. The activity of the used cathode was restored simply through electro-reduction at - 1.0 V vs SCE, and a p-NP removal rate of more than 70% was obtained at 60 min after six regeneration cycles.

Fabrication and characterization of the magnetic separation photocatalyst C-TiO2@Fe3O4/AC with enhanced photocatalytic performance under visible light irradiation.

Congo red (CR) is a kind of refractory contaminant. Conventional biological treatment processes are ineffective for the CR degradation. However, photocatalysis technology could be an alternative for the decomposition of CR because of its high efficiency. In this study, we prepared three kinds of photocatalysts, all of which have advanced visible light excitation characteristics. The magnetic catalyst C-TiO2@Fe3O4/AC was produced by loading C-TiO2 and nano-Fe3O4 onto granular activated carbon (AC). C-TiO2@Fe3O4/AC has a band gap of 2.535 eV, stable magnetic characteristics, and stability toward CR removal. C-TiO2@Fe3O4/AC showed the best performance for CR removal under both simulated sunlight (200-800 nm) and visible light (400-800 nm) irradiation compared to the other catalysts. The CR removal rate reached 92.9% after 30 min of simulated sunlight irradiation, and the reaction rate constant was 0.1776 min-1. Under visible light, the CR removal rate reached 65%. The hydroxyl radical (OH) was detected, and its concentration was determined. Furthermore, the spectral analysis results indicated that the azo bonds and aromatic rings in CR were destroyed. The C-TiO2@Fe3O4/AC has a self-cleaning ability to prevent organic contamination. This study provides a new way of thinking and a simple preparation technique for magnetic visible light catalyst synthesis.