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1.
PLoS One ; 19(4): e0302029, 2024.
Article in English | MEDLINE | ID: mdl-38630727

ABSTRACT

In light of the long-term constraints posed by the "dual carbon" objective, can digital technology emerge as a transformative solution for enterprises to embark on a sustainable development trajectory? The existing body of research has yet to reach a consensus. In order to shed further light on the intricate relationship between digital transformation and ESG performance of enterprises, this study empirically examines the mechanisms and boundaries through which digital transformation influences ESG performance, based on observational data from A-share manufacturing listed companies in Shanghai Stock Exchange and Shenzhen Stock Exchange spanning from 2011 to 2021. The findings demonstrate that digital transformation exerts a significant positive impact on the ESG performance of manufacturing enterprises. Mechanism analysis reveals that the enabling effect of digital transformation primarily enhances company transparency, thereby fostering continuous improvements in ESG performance among manufacturing enterprises. The performance expectation gap will give rise to the phenomenon of "stop-loss in time" and impede the promotional impact of digital transformation. Further investigation into industrial characteristics and industry competition intensity indicates that state-owned enterprises and those operating within highly competitive environments experience more pronounced effects of digital transformation on their ESG performance. This study expands the mechanism and boundary of digital transformation on ESG performance of manufacturing enterprises, and provides a new perspective for manufacturing enterprises to realize the collaborative transformation of digital and green.


Subject(s)
Commerce , Technology , China , Industry , Digital Technology
2.
Chem Commun (Camb) ; 60(24): 3303-3306, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38426541

ABSTRACT

A palladium-catalyzed asymmetric α-arylation of N-carbamoyl imine precursors containing CCl3, CF3 and CF2H is presented. This protocol provides facile access to a series of chiral α-aryl trichloroethylamines bearing various functional groups, with moderate to high yields (40-82% yield) and high enantioselectivity (80-99% ee).

3.
Chem Sci ; 14(41): 11546-11553, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37886092

ABSTRACT

The introduction of difluoromethylene moieties into organic molecules has garnered significant attention due to their profound influence on the physicochemical and biological properties of compounds. Nonetheless, the existing approaches for accessing difluoroalkanes from readily available feedstock chemicals remain limited. In this study, we present an efficient and modular protocol for the synthesis of difluorinated compounds from alkenes, employing the readily accessible reagent, ClCF2SO2Na, as a versatile "difluoromethylene" linchpin. By means of an organophotoredox-catalysed hydrochlorodifluoromethylation of alkenes, followed by a ligated boryl radical-facilitated halogen atom transfer (XAT) process, we have successfully obtained various difluorinated compounds, including gem-difluoroalkanes, gem-difluoroalkenes, difluoromethyl alkanes, and difluoromethyl alkenes, with satisfactory yields. The practical utility of this linchpin strategy has been demonstrated through the successful preparation of CF2-linked derivatives of complex drugs and natural products. This method opens up new avenues for the synthesis of structurally diverse difluorinated hydrocarbons and highlights the utility of ligated boryl radicals in organofluorine chemistry.

4.
Ying Yong Sheng Tai Xue Bao ; 34(6): 1517-1524, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37694413

ABSTRACT

The invasiveness and dissemination of exotic species are strongly influenced by its sexual reproduction characteristics, including blooming characteristics and breeding system. Exploring the association of these sexual reproductive traits with invasiveness would be helpful for revealing the mechanism of its successful invasion. We examined the blooming characteristics and breeding system of Gaura parviflora based on field observations, out-crossing index (OCI) estimation, and hand-pollination experiments. The results showed flowering duration of the G. parviflora population (flowering period) was short (more than 3 months). The life span of single flower (floral longevity) was 40.46 h. Its flower diameter was 3.99 mm. Over seven flowers in bloom per inflorescence and most individuals often bloomed synchronously, which showed a 'mass-flowering pattern'. The changing trend of pollen and stigma vitality was relatively similar, but the duration of stigma vitality was 2 h longer than that of pollen. The stigma and the anthers were close to each other at the initial flowering stage, but the stigma removed from the anthers at the full-blooming stage with the style curving downwards. Many pollinators visited flowers in late full-blooming stage, which were mainly Apis mellifera and Syrphidae spp. Their average visiting frequency was 9.8 times·m-2·h-1. The fruit set in natural pollination after emasculation treatment (insect or wind pollination) was signi-ficantly higher than that in bagged and emasculation treatment, and the treatment of emasculated and bagged with nylon net (excluding insect pollination) could also bear fruits, indicating possible existence of ambophily in G. parviflora. The results of pollen ovule ratio (P/O) mensuration, OCI estimation and hand-pollination experiments showed that its mating system type belonged to additive mixed mating system. So, its characteristics, such as smaller flower size, shorter floral longevity and flowering period, were conducive to allocating more resources to plant growth and seed development, which would help improve its total fitness. The changes of spatial position of male and female organs not only avoided interference between male and female functions, but also created opportunities for stigmas to receive outcross pollen. In addition, the 'mass-flowering pattern' was conducive to attracting pollinators. The pollination mechanism of ambophily was helpful to ensure cross-pollination. The additive mixed mating system could provide double reproductive assurance for this species. These reproductive characteristics were significant for the successful invasion and expansion of G. parviflora.


Subject(s)
Plant Breeding , Reproduction , Humans , Animals , Bees , Pollen , Pollination , Flowers
5.
PeerJ ; 11: e15580, 2023.
Article in English | MEDLINE | ID: mdl-37337583

ABSTRACT

Background: This study aims to analyze the changes of approximately 1 month in fatigue, sleep, and mood in athletes after returning to training following infection with the COVID-19 Omicron strain and provide recommendations for returning to training after infection. Methods: Two hundred and thirty professional athletes who had returned to training after being infected with COVID-19 in December 2022 were recruited to participate in three tests conducted from early January 2023. The second test was completed approximately 1 week after the first, and the third was completed about 2 weeks after the second. Each test consisted of completing scales and the exercise-induced fatigue measure. The scales included a visual analog scale, the Athens Insomnia Scale for non-clinical application, and the Depression-Anxiety-Stress scale. The exercise task was a six-minute stair climb test, and athletes evaluated subjective fatigue levels before and after exercise using another Visual Analog Scale and the Karolinska Sleepiness Scale. Results: After returning to training, athletes' physical fatigue decreased initially but increased as training progressed. Cognitive fatigue did not change significantly. The exercise task led to elevated levels of physical fatigue after a longer duration of training. Sleep quality problems decreased rapidly after the start of training but remained stable with prolonged training. Depression levels continued to decline, while anxiety levels only reduced after a longer duration of training. Stress levels decreased rapidly after the start of training but did not change with prolonged training. Conclusion: Athletes who return to training after recovering from COVID-19 experience positive effects on their fatigue, sleep, and mood. It is important to prioritize anxiety assessment and interventions during the short period after returning and to continue monitoring fatigue levels and implementing recovery interventions over a longer period of time.


Subject(s)
Affect , Athletes , COVID-19 , Exercise , Sleep , Humans , Athletes/psychology , COVID-19/pathology , COVID-19/psychology , COVID-19/virology , Exercise/psychology , Exercise/statistics & numerical data , Male , Female , Adolescent , Young Adult , Adult , SARS-CoV-2 , Surveys and Questionnaires , Time Factors , Diagnostic Self Evaluation
6.
Discov Nano ; 18(1): 40, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36969494

ABSTRACT

Abstract: Ischemic stroke is one of the most severe neurological disorders with limited therapeutic strategies. The utilization of nanoparticle drug delivery systems is a burgeoning field and has been widely investigated. Among these, biomimetic drug delivery systems composed of biogenic membrane components and synthetic nanoparticles have been extensively highlighted in recent years. Biomimetic membrane camouflage presents an effective strategy to prolong circulation, reduce immunogenicity and enhance targeting. For one thing, biomimetic nanoparticles reserve the physical and chemical properties of intrinsic nanoparticle. For another, the biological functions of original source cells are completely inherited. Compared to conventional surface modification methods, this approach is more convenient and biocompatible. In this review, membrane-based nanoparticles derived from different donor cells were exemplified. The prospect of future biomimetic nanoparticles in ischemic stroke therapy was discussed.

7.
ACS Macro Lett ; 12(2): 263-268, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36734851

ABSTRACT

A coumarinacyl anilinium (CAA) salt, facilely synthesized via a one-pot reaction, is shown to be a versatile visible and NIR photoinitiator for cationic and step-growth polymerizations. CAA salt exhibits superior photoinitiation performance as compared to commercial iodonium salt in cationic polymerization. Upon visible-light irradiation, this salt undergoes hemolytic and heterolytic cleavage and subsequent electron transfer and hydrogen abstraction reactions, forming reactive species capable of initiating cationic polymerization of epoxides and vinyl monomers. After a short irradiation period, polymerization also proceeds in the dark due to the non-nucleophilic nature of the counteranion. NIR-induced polymerizations were successfully conducted based on upconversion photochemistry. CAA salt can also initiate step-growth polymerization of N-ethyl carbazole (NEC) by oxidation of the monomer by the photochemically formed anilium radical cations. Subsequent proton release and radical coupling reactions essentially yield polycarbazole. CAA salt, featuring straightforward synthesis and long-wavelength sensitivity as well as versatile photoinitiating performance, has great potential in various applications.

8.
Front Physiol ; 14: 1247659, 2023.
Article in English | MEDLINE | ID: mdl-38260100

ABSTRACT

Purpose: This study aims to explore the relationship between the dynamic changes in oxygen uptake (V˙O2) and deoxyhemoglobin (HHb) and peripheral fatigue in athletes during incremental exhaustive exercise under different environmental conditions, including high temperature and humidity environment, hypoxic environment, and normal conditions. Methods: 12 male modern pentathlon athletes were recruited and performed incremental exhaustive exercise in three different environments: normal condition (23°C, 45%RH, FiO2 = 21.0%, CON), high temperature and humidity environment (35°C, 70%RH, FiO2 = 21.0%, HOT), and hypoxic environment (23°C, 45%RH, FiO2 = 15.6%, HYP). Gas metabolism data of the athletes were collected, and muscle oxygen saturation (SmO2) and total hemoglobin content in the vastus lateralis muscles (VL) were measured to calculate the deoxyhemoglobin content. Linear and nonlinear function models were used to fit the characteristic parameters of V˙O2 and HHb changes. Results: The results showed that compared to the CON, V˙O2, V˙CO2, and exercise time were decreased in the HOT and HYP (p < 0.05). ΔEV˙O2 and OUES were reduced in the HOT and HYP compared to the CON (p < 0.05). The Gas exchange threshold in the CON corresponded to higher V˙O2 than in the HYP and HOT (p < 0.05). ΔEV˙O2-1 was reduced in the HOT compared to the HYP (p < 0.05). ΔEHHb was higher in the HOT compared to the CON (p < 0.05). ΔEHHb-1 was increased in the HYP compared to the CON (p < 0.05). There was a negative correlation between ΔEHHb and corresponding V˙O2⁡max in the HOT (r = -0.655, p < 0.05), and a negative correlation between ΔEHHb-1 and corresponding V˙O2⁡max in the HYP (r = -0.606, p < 0.05). Conclusion: Incremental exhaustive exercise in hypoxic environment and high temperature and humidity environments inhibits gas exchange and oxygen supply to skeletal muscle tissue in athletes. For athletes, the accelerated deoxygenation response of skeletal muscles during incremental exhaustive exercise in high temperature and humidity environments, as well as the excessive deoxygenation response before BP of deoxyhemoglobin in hypoxic environment, may be contributing factors to peripheral fatigue under different environmental conditions.

9.
Angew Chem Int Ed Engl ; 59(34): 14347-14351, 2020 Aug 17.
Article in English | MEDLINE | ID: mdl-32506841

ABSTRACT

Asymmetric catalysis with benzyne remains elusive because of the highly fleeting and nonpolar nature of benzyne intermediates. Reported herein is an electrochemical approach for the oxidative generation of benzynes (cyclohexyne) and its successful merging with chiral primary aminocatalysis, formulating the first catalytic asymmetric enamine-benzyne (cyclohexyne) coupling reaction. Cobalt acetate was identified to stabilize the in situ generated arynes and facilitate its coupling with an enamine. This catalytic enamine-benzyne protocol provides a concise method for the construction of diverse α-aryl (α-cyclohexenyl) quaternary carbon stereogenic centers with good stereoselectivities.

10.
Chemistry ; 25(43): 10033-10044, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31026120

ABSTRACT

Asymmetric electrochemical catalysis, an emerging frontline in asymmetric catalysis and electro-organic synthesis, is summarized. Representative works are classified, with respect to the external chiral resources, including chiral media, chiral mediator, chiral catalyst, and chiral electrode. This concept article is expected to provide readers with the general concepts and perspectives of each chiral electrochemical catalysis mode, and to indicate the potential and future development of asymmetric electrochemical catalysis.

11.
Org Lett ; 20(5): 1324-1327, 2018 03 02.
Article in English | MEDLINE | ID: mdl-29425046

ABSTRACT

The electro-oxidative generation of diaza-oxyallyl cation and its application to the synthesis of diamine motifs has been explored. Because of the synergistic combination of anodic and cathodic reactions, the current electrochemical method not only avoids the use of a stoichiometric amount of chemical oxidant but also eliminates the need for supporting electrolyte and external base required for effective oxidation.

12.
Org Lett ; 19(8): 2122-2125, 2017 04 21.
Article in English | MEDLINE | ID: mdl-28394132

ABSTRACT

Catalytic asymmetric electrochemical C-H functionalization of simple ketones has been developed. The transformation is realized by the combination of electrochemical oxidation and chiral primary amine catalysis. This metal- and oxidant-free method furnishes diverse C1-alkylated tetrahydroisoquinolines in high yields and with excellent enantioselectivities under very mild conditions.

13.
J Org Chem ; 80(21): 11021-30, 2015 Nov 06.
Article in English | MEDLINE | ID: mdl-26444498

ABSTRACT

An effective Friedel-Crafts alkylation reaction of electron-rich aromatics with N-vinylamides, induced by electrochemically in situ-generated TBPA radical cation, has been developed; the resulting adducts are produced in good to excellent yields. In the "ex-cell" type electrolysis, TBPA is transformed to its oxidized form in situ and subsequently employed as an electron transfer reagent to initiate a cationic chain reaction. An easily recoverable and reusable polymeric ionic liquid-carbon black (PIL-CB) composite was also utilized as a supporting electrolyte for the electrochemical generation of TBPA cation radical, without sacrificing efficiency or stability after four electrolyses. Cyclic voltammetry analysis and the results of control experiments demonstrate that the reaction of electron-rich aromatics and N-vinylamides occurs via a cationic chain reaction, which takes place though an oxidative activation of a C-H bond of electron-rich aromatics instead of oxidation of the N-vinylamide as previously assumed.

14.
Angew Chem Int Ed Engl ; 54(12): 3744-7, 2015 Mar 16.
Article in English | MEDLINE | ID: mdl-25619992

ABSTRACT

One of the major impediments to using electroorganic synthesis is the need for large amounts of a supporting electrolyte to ensure the passage of charge. Frequently this causes separation and waste problems. To address these issues, a polymeric ionic liquid-Super P carbon black composite has been formulated. The system enables electrolyses to be performed without adding an additional supporting electrolyte, and its efficient recovery and reuse. In addition, the ability of the composite to modify the electrode surface in situ leads to improved kinetics. A practical consequence is that one can decrease catalyst loading without sacrificing efficiency.

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