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1.
Chemistry ; 29(33): e202300719, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-36928880

RESUMO

The Pd-catalyzed Suzuki-Miyaura cross-couplings (SMRs) are utilized as the most practical method to construct C-C bond, especial for biaryls. However, a major disadvantage of current protocols is the requirement of excess organoboron coupling partner (1.5-3.0 equiv.). Herein, a novel palladacyclic 1,3-bis(2,6-diisopropylphenyl)acenaphthoimidazol-2-ylidene (AnIPr) precatalyst possessing a chiral oxazoline was designed, which enabled a general protocol towards bulky tri-ortho-substituted biaryls, ternaphthalenes and diarylanthracenes via the Pd-catalyzed SMR employing equimolar organoborons and aryl bromides. A remarkable scope of substrates with various functional groups and heterocycles were well compatible with an adaptability to synthesize useful ligands.


Assuntos
Brometos , Paládio , Paládio/química , Catálise , Ligantes , Brometos/química
2.
J Environ Manage ; 275: 111221, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956918

RESUMO

Accurately assessing the effectiveness of industrial carbon emission reduction in each province and optimizing the emission reduction path have important practical significance for China's Nationally Determined Contribution (NDC) emission reduction achievement targets. This study first evaluates the industry's emission reduction effects across 30 provinces of China. Then, the emission reduction paths of "lagging regions," which fail to meet the 2030 industrial carbon emission reduction target, are optimized based on the two-dimensional perspective of carbon emission efficiency and emission reduction cost. This study found that (1) China has exceeded its 2020 industrial carbon emission reduction target. There are 9 potential "lagging regions" that failed to meet their 2020 targets, (2) if the current emission reduction rate is maintained, China is capable of exceeding its 2030 industrial carbon emission reduction target, but there are still 11 "lagging regions," (3) there are clear differences in carbon emission efficiency and shadow price among the "lagging regions," and (4) under the premise of ensuring feasibility and fairness, the three provinces of Liaoning, Guangxi, and Shaanxi can set strict emission reduction targets, while other "lagging regions" can set flexible targets.


Assuntos
Carbono , Indústrias , Carbono/análise , Dióxido de Carbono/análise , China , Custos e Análise de Custo
3.
Sci Rep ; 14(1): 13118, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849506

RESUMO

Quantum computing has already demonstrated great computational potential across multiple domains and has received more and more attention. However, due to the connectivity limitations of Noisy Intermediate-Scale Quantum (NISQ) devices, most of the quantum algorithms cannot be directly executed without the help of inserting SWAP gates. Nevertheless, more SWAP gates lead to a longer execution time and, inevitably, lower fidelity of the algorithm. To this end, this paper proposes an optimized qubit mapping algorithm based on a dynamic look-ahead strategy to minimize the number of SWAP gates inserted. Firstly, a heuristic algorithm is proposed based on maximizing physical qubit connectivity to generate the optimal initial qubit mapping, which reduces the need for logical qubit shifts during subsequent SWAP gate insertion. Secondly, in the form of directed acyclic graphs, we identify quantum gates that violate the constraints of physical coupling and insert SWAP gates to remap qubits, thereby overcoming the limitations of qubit interactions. Finally, the optimal SWAP gate insertion strategy is built by comparing the cost of different SWAP gate insertion strategies through a multi-window look-ahead strategy to reduce the number of SWAP gates inserted. The experimental results show that the strategy in this paper decreases the number of SWAP gate insertions and significantly reduces the depth of quantum circuits when performing qubit mapping compared with state-of-the-art methods.

4.
Chem Commun (Camb) ; 56(17): 2630-2633, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32016259

RESUMO

Two efficient photosensitizers (PSs) with aggregation-induced emission characteristics were designed and synthesized for specific lysosome-targeted photodynamic therapy (PDT). Both PSs efficiently discriminated Gram-positive bacteria from Gram-negative bacteria and killed Gram-positive bacteria through the PDT effect.


Assuntos
Bactérias Gram-Positivas/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Bactérias Gram-Positivas/metabolismo , Células HeLa , Humanos , Lisossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
5.
Reprod Sci ; 26(11): 1468-1475, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30819044

RESUMO

Apoptosis is an interactive and dynamic biological process involved in all phases of embryogenesis. If apoptosis dominates the trophoblast cell growth process, it will result in adverse pregnancy outcomes. X-linked inhibitor of apoptosis protein (XIAP) is a potent caspase inhibitor and an important barrier to apoptotic cell death. MicroRNAs involve in posttranscriptional gene expression regulation and apoptosis. Online sequence alignment analysis showed that there was a putative binding site of miR-371a-5p on the 3'-untranslated region (UTR) of XIAP. Thirty chorionic villi samples were collected to examine the expression of miR-371a-5p and XIAP. The dual-luciferase reporter assay was applied to determine the relationship between miR-371a-5p and XIAP by human placental choriocarcinoma cells (JEG-3) cells in vitro. After 48-hour transfection of mimics and inhibitor by JEG-3 cells in vitro, Western blotting was used to, respectively, detect the protein expression levels of XIAP and caspase-3. Flow cytometry was used to validate the apoptosis ratio of transfection. The expression of miR-371a-5p and XIAP in recurrent pregnancy loss was greatly decreased. The results from the luciferase reporter assay strongly suggested binding of the XIAP 3'-UTR by miR-371a-5p. Apoptosis percentage of miR-371a-5p mimic was significantly greater than that of normal control. However, apoptosis percentage of miR-371a-5p inhibitor was significantly lower than that of normal control. A significant decrease in luciferase activity was observed in miR-371a-5p mimics-transfected JEG-3 cells compared with controls. These findings provide the evidence that miR-371a-5p is one of the regulating factors according to apoptosis pathway of XIAP-caspase-3 and may be involved in the pathogenesis of recurrent pregnancy loss.


Assuntos
Aborto Habitual/metabolismo , MicroRNAs/biossíntese , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/biossíntese , Aborto Habitual/genética , Adulto , Apoptose/fisiologia , Linhagem Celular Tumoral , Células Cultivadas , Vilosidades Coriônicas/metabolismo , Feminino , Humanos , MicroRNAs/genética , Gravidez , Ligação Proteica/fisiologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética
6.
RSC Adv ; 8(27): 14995-15000, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35541307

RESUMO

In this work, we report a fluorescent probe (TPEQN-P) for detecting alkaline phosphatase (ALP) with high sensitivity and monitoring its activity based on the specific aggregation-induced emission (AIE) effect. TPEQN-P can be constructed by conjugating the phosphate moiety into an AIE molecule (TPE-QI) through a reactive p-hydroxybenzyl group, which exhibits very weak emission in aqueous media due to its good water solubility. In the presence of ALP, TPEQN-P undergoes dephosphorylation and releases the hydrolysis product TPE-QI, which is intensely fluorescent because of its poor water solubility. The detection limit for ALP using TPEQN-P can be as low as 0.0077 U L-1 with a linear range of 0-30 mU mL-1 in solution. TPEQN-P also shows excellent applicability in serum samples, demonstrating potential applications in clinical diagnosis and biomedical research. TPEQN-P also can be applied for the determination of ALP activity and in ALP inhibitor screening.

7.
PLoS One ; 9(12): e114638, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25506839

RESUMO

In this work, the positively or negatively charged anatase TiO2 nanoparticles were synthesized via a low temperature precipitation-peptization process (LTPPP) in the presence of poly(ethyleneimine) (PEI) and poly(sodium4- styrenesulfonate) (PSS). X-ray diffraction (XRD) pattern and high-resolution transmission electron microscope (HRTEM) confirmed the anatase crystalline phase. The charges of the prepared TiO2, PEI-TiO2 and PSS-TiO2 nanoparticles were investigated by zeta potentials. The results showed that the zeta potentials of PEI-TiO2 nanoparticles can be tuned from +39.47 mV to +95.46 mV, and that of PSS-TiO2 nanoparticles can be adjusted from -56.63 mV to -119.32 mV. In comparison with TiO2, PSS-TiO2 exhibited dramatic adsorption and degradation of dye molecules, while the PEI modified TiO2 nanoparticles showed lower photocatalytic activity. The photocatalytic performances of these charged nanoparticles were elucidated by the results of UV-vis diffuse reflectance spectra (DRS) and the photoluminescence (PL) spectra, which indicated that the PSS-TiO2 nanoparticles showed a lower recombination rate of electron-hole pairs than TiO2 and PEI-TiO2.


Assuntos
Corantes/isolamento & purificação , Nanopartículas/química , Fotólise , Titânio/química , Catálise , Temperatura Baixa , Nanopartículas/ultraestrutura , Polietilenoimina/química , Polímeros/química , Ácidos Sulfônicos/química , Difração de Raios X
8.
Toxicol Lett ; 221(3): 212-8, 2013 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-23831946

RESUMO

Preterm birth is the leading cause of death for newborn infants, and lipopolysaccharide (LPS) is commonly used to induce preterm delivery in experimental animals. Pyrrolizidine alkaloids (PAs) are widespread and occur in foods, herbs, and other plants. This study was to investigate the synergistic effects of LPS and two representative PAs, retrorsine (RTS) and monocrotaline (MCT), on preterm delivery and fetal death. Pregnant Kunming mice were divided into seven groups: control, RTS, MCT, LPS, RTS+LPS and two MCT+LPS groups. Animals in PAs and PAs+LPS groups were dosed intragastrically with RTS (10mg/kg) or MCT (20 mg/kg or 60 mg/kg) from gestational day (GD) 9 to GD16; mice given LPS were injected intraperitoneally with 150 µg/kg on GD15.5. Latencies to delivery, numbers of pups live and dead at birth were recorded, and livers of live neonates were collected. The incidence of LPS-induced preterm birth was enhanced in dams pretreated with MCT, and combination of PAs and LPS increased fetal mortality from PAs. The enhancement of LPS-induced preterm delivery and fetal demise in animals exposed chronically to PAs and other substances found in foods and beverages consumed widely by humans merits further focused investigation.


Assuntos
Morte Fetal/induzido quimicamente , Lipopolissacarídeos/toxicidade , Nascimento Prematuro/induzido quimicamente , Alcaloides de Pirrolizidina/toxicidade , Animais , Animais Recém-Nascidos , Feminino , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Gravidez , Organismos Livres de Patógenos Específicos , Estatísticas não Paramétricas , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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