In recent years, much interest has been paid to difluoromethylthiolated molecules as the “SCF2” moiety is a key motif in drug and agrochemical research. Consequently, the development of versatile ...strategies for the selective synthesis of SCF2H‐ and SCF2FG‐containing molecules (FG=functional group) has attracted a lot of attention and inspired the scientific community to design new tools. This Minireview highlights the major progress made in this field. Particularly, methodologies developed for the difluoromethylation of sulfur‐containing molecules and the direct construction of C−SCF2 bonds in various classes of compounds are showcased and discussed.
Compliments to the C−F: The development of versatile strategies for the selective synthesis of SCF2H‐ and SCF2FG‐containing molecules (FG=functional group) has attracted a lot of attention. This Minireview highlights the major progress made in this field, including methodologies developed for the difluoromethylation of sulfur‐containing molecules and the direct construction of C−SCF2 bonds in various classes of compounds.
The rapid development of online technology has facilitated the gradual growth and development of e-commerce and online marketing, creating a new business model and new opportunities. This has had a ...major impact on the future development of the market economy and the international competitiveness of companies and countries. At the same time, its appearance has also subverted the traditional retail market, and the convenience, reliability, and security of payment have been quickly recognized by people. Technological innovations represented by artificial intelligence have driven the development of the digital economy for decades. In order to better strengthen the statistics of the online shopping market and promote the development of the real economy, this study discusses the analysis of consumer behavior in online shopping based on the market changes of artificial intelligence and digital economy. Through the questionnaire, it can be found that all age groups have been exposed to online shopping, most of them are young people, and the number of shopping per month is still concentrated between 4 and 11 times. The study also examined the size of China’s online retail market and found that there were 820 million Internet shoppers in China by December 2021, which is forecast to be 910 million by 2022. The report also found that the B2C market share will reach nearly 61% in 2021 due to the B2C model featuring higher quality goods and more guaranteed services.
Chemical contamination in food is one of the most serious food safety problems. Competitive enzyme-linked immunosorbent assay (Cp-ELISA) is the most widely used analytical tool for detection of food ...chemical contaminants due to its high throughput, low cost, and straightforward readouts. However, conventional ELISA suffers from low sensitivity, which greatly limits its potential in highly sensitive detection. To fulfill increasingly stringent control requirement for chemical contaminants in food, improving the sensitivity of Cp-ELISA is important and meaningful. In this paper, we will briefly review various emerging strategies for increasing Cp-ELISA sensitivity, including: 1) screening higher affinity antibodies to target antigens; 2) preparing competing antigens with lower affinity to antibodies; 3) employing signal amplification; and 4) introducing novel signal transducer elements. This review will focus on clarifying the underlying mechanisms of these strategies in improving sensitivity and providing a careful comparison. Brief discussion on challenges and future directions will be elaborated.
•Emerging strategies for improving the detection sensitivity of competitive ELISA was systematically reviewed.•Three core elements of antibodies, competing antigens and signal transducers in competitive ELISA were highlighted.•Typical applications for food chemical contamination detection were selected.•This work perhaps stimulates an extensive and deep research in this field.
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► Mainland China and adjacent areas harbor the world’s most diverse temperate flora. ► We review the phylogeographic literature on this flora for the first time. ► Studies generally ...reveal strong genetic imprints of Quaternary climate and environmental change. ► This challenges the oft-stated view of East Asia as a glacial sanctuary for temperate plants.
The Sino-Japanese Floristic Region (SJFR) of East Asia harbors the most diverse of the world’s temperate flora, and was the most important glacial refuge for its Tertiary representatives (‘relics’) throughout Quaternary ice-age cycles. A steadily increasing number of phylogeographic studies in the SJFR of mainland China and adjacent areas, including the Qinghai–Tibetan-Plateau (QTP) and Sino-Himalayan region, have documented the population histories of temperate plant species in these regions. Here we review this current literature that challenges the oft-stated view of the SJFR as a glacial sanctuary for temperate plants, instead revealing profound effects of Quaternary changes in climate, topography, and/or sea level on the current genetic structure of such organisms. There are three recurrent phylogeographic scenarios identified by different case studies that broadly agree with longstanding biogeographic or palaeo-ecological hypotheses: (i) postglacial re-colonization of the QTP from (south-)eastern glacial refugia; (ii) population isolation and endemic species formation in Southwest China due to tectonic shifts and river course dynamics; and (iii) long-term isolation and species survival in multiple localized refugia of (warm-)temperate deciduous forest habitats in subtropical (Central/East/South) China. However, in four additional instances, phylogeographic findings seem to conflict with a priori predictions raised by palaeo-data, suggesting instead: (iv) glacial in situ survival of some hardy alpine herbs and forest trees on the QTP platform itself; (v) long-term refugial isolation of (warm-)temperate evergreen taxa in subtropical China; (vi) ‘cryptic’ glacial survival of (cool-)temperate deciduous forest trees in North China; and (vii) unexpectedly deep (Late Tertiary/early-to-mid Pleistocene) allopatric-vicariant differentiation of disjunct lineages in the East China-Japan-Korea region due to past sea transgressions. We discuss these and other consequences of the main phylogeographic findings in light of palaeo-environmental evidence, emphasize notable gaps in our knowledge, and outline future research prospects for disentangling the evolution and biogeographic history of the region’s extremely diverse temperate flora.
East Asia's temperate deciduous forests served as sanctuary for Tertiary relict trees, but their ages and response to past climate change remain largely unknown. To address this issue, we elucidated ...the evolutionary and population demographic history of Cercdiphyllum, comprising species in China/Japan (Cercdiphyllum japonicum) and central Japan (Cercdiphyllum magnificum).
Fifty-three populations were genotyped using chloroplast and ribosomal DNA sequences and microsatellite loci to assess molecular structure and diversity in relation to past (Last Glacial Maximum) and present distributions based on ecological niche modelling.
Late Tertiary climate cooling was reflected in a relatively recent speciation event, dated at the Mio-/Pliocene boundary. During glacials, the warm-temperate C. japonicum experienced massive habitat losses in some areas (north-central China. north Japan) but increases in others (southwest/-east China, East China Sea landbridge, south Japan). In China, the Sichuan Basin and/or the middle-Yangtze were source areas of postglacial northward recolonization; in Japan, this may have been facilitated through introgressive hybridization with the cool-temperate C. magnificum.
Our findings challenge the notion of relative evolutionary and demographic stability of Tertiary relict trees, and may serve as a guideline for assessing the impact of Neogene climate change on the evolution and distribution of East Asian temperate plant.
OBJECTIVESIn late December 2019, an outbreak of coronavirus disease (COVID-19) in Wuhan, China was caused by a novel coronavirus, newly named severe acute respiratory syndrome coronavirus 2. We aimed ...to quantify the severity of COVID-19 infection on high-resolution chest computed tomography (CT) and to determine its relationship with clinical parameters.
MATERIALS AND METHODSFrom January 11, 2020, to February 5, 2020, the clinical, laboratory, and high-resolution CT features of 42 patients (26–75 years, 25 males) with COVID-19 were analyzed. The initial and follow-up CT, obtained a mean of 4.5 days and 11.6 days from the illness onset were retrospectively assessed for the severity and progression of pneumonia. Correlations among clinical parameters, initial CT features, and progression of opacifications were evaluated with Spearman correlation and linear regression analysis.
RESULTSThirty-five patients (83%) exhibited a progressive process according to CT features during the early stage from onset. Follow-up CT findings showed progressive opacifications, consolidation, interstitial thickening, fibrous strips, and air bronchograms, compared with initial CT (all P < 0.05). Before regular treatments, there was a moderate correlation between the days from onset and sum score of opacifications (R = 0.68, P < 0.01). The C-reactive protein, erythrocyte sedimentation rate, and lactate dehydrogenase showed significantly positive correlation with the severity of pneumonia assessed on initial CT (Rrange, 0.36–0.75; P < 0.05). The highest temperature and the severity of opacifications assessed on initial CT were significantly related to the progression of opacifications on follow-up CT (P = 0.001–0.04).
CONCLUSIONSPatients with the COVID-19 infection usually presented with typical ground glass opacities and other CT features, which showed significant correlations with some clinical and laboratory measurements. Follow-up CT images often demonstrated progressions during the early stage from illness onset.
Background and Aims
Accurate assessment of liver functional reserve pre‐operatively is vital for safe hepatic resection. The ALBI score is a new model for assessing liver function. This study aimed ...to evaluate the value of combining ALBI score with sFLR in predicting post‐operative morbidity and PHLF in HCC patients who underwent hepatectomy.
Methods
Patients undergoing three‐dimensional CT reconstruction prior to hepatectomy for HCC between January 2015 and January 2017 were enrolled. The values of the CP score, ALBI score and sFLR in predicting post‐operative outcomes were evaluated.
Results
A total of 229 HCC patients were enrolled; 24 (10.5%) experienced major complications and 21 (9.2%) developed PHLF. The incidence of major complications and PHLF increased with increasing ALBI grade. The ALBI grade classified patients with CP grade A into two subgroups with different incidences of PHLF (P=.029). sFLR and ALBI scores were identified as independent predictors of PHLF. The AUC values for the CP score, ALBI score, sFLR and sFLR×ALBI for predicting major complications were 0.600, 0.756, 0.660 and 0.790 respectively. The AUC values of the CP score, ALBI score, sFLR and sFLR×ALBI for predicting PHLF were 0.646, 0.738, 0.758 and 0.884 respectively.
Conclusions
The ALBI score showed superior predictive value of post‐operative outcomes over CP score, and the combination of sFLR and ALBI score was identified as a stronger predictor of post‐operative outcomes than the sFLR or ALBI score alone.
Warm‐temperate evergreen (WTE) forest represents the typical vegetation type of subtropical China, but how its component species responded to past environmental change remains largely unknown. Here, ...we reconstruct the evolutionary history of Tetrastigma hemsleyanum, an herbaceous climber restricted to the WTE forest. Twenty populations were genotyped using chloroplast DNA sequences and nuclear microsatellite loci to assess population structure and diversity, supplemented by phylogenetic dating, ancestral area reconstructions and ecological niche modeling (ENM) of the species distributions during the Last Glacial Maximum (LGM) and at present. Lineages in Southwest vs Central‐South‐East China diverged through climate/tectonic‐induced vicariance of an ancestral southern range during the early Pliocene. Long‐term stability in the Southwest contrasts with latitudinal range shifts in the Central‐South‐East region during the early‐to‐mid‐Pleistocene. Genetic and ENM data strongly suggest refugial persistence in situ at the LGM. Pre‐Quaternary environmental changes appear to have had a persistent influence on the population genetic structure of this subtropical WTE forest species. Our findings suggest relative demographic stability of this biome in China over the last glacial–interglacial cycle, in contrast with palaeobiome reconstructions showing that this forest biome retreated to areas of today's tropical South China during the LGM.
Phylogeography has been one major focus of evolutionary biology in recent years, with many important advances in Chinese species. In this issue, we collected 11 phylogeographic studies of plants by ...Chinese laboratories. We further synthesized the main findings and patterns emerging from these and previous phylogeographic studies in China and asked where phylogeographic research should be directed in the coming years. Numerous examples have shown that phylogeographic patterns in China did not show an expected expansion–contraction pattern at large scale, mirroring the geological records showing that no unified ice sheet had developed in China during the Quaternary Period. Instead, regional expansions and intraspecific divergences are very common in most studied species during the Quaternary oscillations. Different intraspecific lineages or alleles (haplotypes) were detected in multiple localized refugia, from where regional or local expansions are likely to have started. Hybridizations and introgressions are frequent between intraspecific lineages or between different species. We also reviewed computational methods for phylogeographic analyses. Despite the great progress made in recent years, there remains much to discover about the spatial–temporal dimensions and underlying speciation mechanisms of Chinese plants. Phylogeographic studies represent a key knot that connects the genus phylogeny (macroevolution) and speciation and adaptation (microevolution). Therefore, we advocate that: (i) phylogeographic studies of plants in China should be directed to the closely related species or a monophyletic group (for example, a genus or a section) in the coming years; and (ii) population genetic data based on direct sequencing multiple loci, especially those from nuclear genome and statistical tests should be widely adopted and enforced. The recovered intraspecific divergences and phylogeographic patterns of multiple‐species may allow us to better understand the high plant diversity in China and set up concrete hypotheses for studying plant speciation and diversification mechanisms in this region.
Poor oxygen diffusion at multiphase interfaces in an air cathode suppresses the energy densities of zinc–air batteries (ZABs). Developing effective strategies to tackle the issue is of great ...significance for overcoming the performance bottleneck. Herein, inspired by the bionics of diving flies, a polytetrafluoroethylene layer was coated on the surfaces of Co3O4 nanosheets (NSs) grown on carbon cloth (CC) to create a hydrophobic surface to enable the formation of more three‐phase reaction interfaces and promoted oxygen diffusion, rendering the hydrophobic‐Co3O4 NSs/CC electrode a higher limiting current density (214 mA cm−2 at 0.3 V) than that (10 mA cm−2) of untreated‐Co3O4 NSs/CC electrode. Consequently, the assembled ZAB employing hydrophobic‐Co3O4 NSs/CC cathode acquired a higher power density (171 mW cm−2) than that (102 mW cm−2) utilizing untreated‐Co3O4 NSs/CC cathode, proving the enhanced interfacial reaction kinetics on air cathode benefiting from the hydrophobization engineering.
A bionic‐inspired hydrophobization engineering of electrocatalysts is developed to enable the formation of more three‐phase reaction interfaces and promoted oxygen diffusion on an air cathode, achieving enhanced electrocatalytic efficiency toward zinc–air battery with higher energy density in comparison with that employing the air cathode without hydrophobic surface design.
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