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Abstract Fine constructing the chemical environment of the central metal is vital in developing efficient single‐atom catalysts (SACs). Herein, the atomically dispersed Cu on the N‐doped carbon is modulated by introducing CuP moiety to CuNC SAC. Through fine‐tuning with another heteroatom P, the Cu SAC shows the superior performance of ethylene oxychlorination. The Cu site activity of Cu‐NPC is four times higher than the P‐free Cu‐NC catalyst and 25 times higher than the Ce‐promoted CuCl2/Al2O3 catalyst in the long‐term test (>200 h). The selectivity of ethylene dichloride can be splendidly kept at ≈99%. Combined experimental and simulation studies provide a theoretical framework for the coordination of Cu, N, and P in the complex active center and its role in effectively catalyzing ethylene oxychlorination. It integrates the oxidation and chlorination reactions with superior catalytic performance and unrivaled ability of corrosive‐HCl resistance. The concept of fine constructing with another heteroatom is anticipated to provide with inspiration for rational catalyst design and expand the applications of carbon‐based SACs in heterogeneous catalysis.

ObjectivesThe study aimed to determine whether SARS-CoV-2 Omicron variant could be detected in the vaginal fluid and anal swabs of reproductive-aged and postmenopausal women infected with SARS-CoV-2 Omicron variant.MethodsIncluded in this study were 63 women who were laboratory confirmed as having SARS-CoV-2 Omicron variant infection and admitted to the responsible ward of Daping Hospital of at the National Exhibition and Convention Center(Shanghai) Makeshift Hospital from May 1–24, 2022.From them, vaginal and anal swabs were obtained with informed consent. The demographic and baseline clinical characteristics and the swab test results were analyzed.ResultsThe 63 included patients ranged in age from 18 to 72 years with a median of 47.71 ± 15.21 years. Of them, 38 women (60.3%) were in their reproductive years. Most of the participants (77.8%) were healthy without significant underlying diseases. Fourteen patients (22.2%) had asymptomatic infection and the remaining 49 (77.8%) had mild infection. The upper respiratory tract symptoms including cough (40/63.5%) and sore throat (18/28.6%)were the most common clinical manifestations of these mildly infected patients. Only 5 patients (7.8%) had gastrointestinal (GI) symptoms, including simple diarrhea in 4 patients, and diarrhea with vomiting in one patient. Pharyngeal,vaginal and anal swabs were collected simultaneously from all 63 patients 8–16 (mean 11.25 ± 2.23) days after SARS-Cov-2 Omicron variant infection. The vaginal swabs were negative for SARS-CoV-2 in all 63 patients, and the anal swabs were positive in 4 patients (6.5%). The overall median hospitalization duration was 16.73 ± 3.16 days.ConclusionThe results of the present study suggest that there is a low possibility of SARS-Cov-2 Omicron variant transmission via the digestive tract and vaginal fluid. The correlation between the GI symptoms and the presence of viral RNA in anal swabs is uncertain.

Engineering unique electronic structure of catalyst to boost catalytic performance is of prime scientific and industrial importance. Herein, the identification of intrinsic electronic sensitivity for direct propene epoxidation was first achieved over highly stable Au/wormhole-like TS-1 catalyst. Results show that the electron transfer of Au species can be regulated by manipulating the dynamic evolutions and contents of Au valence states, thus resulting in different catalytic performance in 100 h time-on-stream. By DFT calculations, kinetic analysis and multi-characterizations, it is found that the Au0 species with higher electronic population can easily transfer more electrons to activate surface O2 compared with Au1+ and Au3+ species. Moreover, there is a positive correlation between Au0 content and activity. Based on this correlation, a facile strategy is further proposed to boost Au0 percentage, resulting in the reported highest PO formation rate without adding promoters. This work harbors tremendous guiding significance to the design of highly efficient Au/Ti-containing catalyst for propene epoxidation with H2 and O2.

Objectives: It was the aim of this study to investigate the feasibility of polymerase chain reaction (PCR)/ligase detection reaction (LDR)/capillary electrophoresis for the detection of paternally inherited fetal CD17 (A→T) mutation of β-thalassemia in maternal plasma. Methods: The target DNA in maternal plasma was amplified by PCR and the mutant signal was detected by LDR. Unique LDR products were produced and separated by capillary electrophoresis. PCR/LDR/capillary electrophoresis was applied to detect CD17 (A→T) mutation in an experimental model at different sensitivity levels and from 3 maternal plasma samples. Results: The sensitivity of PCR/LDR/capillary electrophoresis for detecting low-abundance CD17 (A→T) mutation was 1:5,000 at least. The technique was applied in maternal plasma DNA for detecting paternally inherited fetal CD17 (A→T) mutation, and the results were concordant with that of PCR/reverse dot blot of amniotic fluid cell DNA. Conclusions: PCR/LDR/capillary electrophoresis has a very high sensitivity to distinguish low-abundance single nucleotide differences and probably detects paternally inherited fetal point mutations in maternal plasma. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]