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1.
Food Chem ; 335: 127655, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32731125

RESUMO

In the present study, the profile of phenolic compounds in colored (white, yellow, black and blue) naked barley was detected and their content and antioxidant abilities were investigated. The results showed that there were 156 phenolic substances identified, including monophenol, phenolic acids, flavonoids and other polyphenols. The black sample had the most types of phenolic. The content of phenolic varies depending on color of naked barley and the highest values of total phenolic acid and total flavonoids were observed in black and white samples. Furthermore, the strongest ferric reducing antioxidant power and the free radical scavenging ability of DPPH, ABTS, and superoxide anion showed in white, white, yellow and black naked barley. While white and yellow samples had the strongest scavenging ability of hydroxyl radical. There was significant correlation between phenolic components and anti-oxidation. This study suggests that colored naked barley grains are rich in phenolic compounds with antioxidant capacity.

2.
Biochim Biophys Acta Gen Subj ; 1865(1): 129756, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33010351

RESUMO

BACKGROUND: Crotonase superfamily members exhibit great catalytic diversity towards various acyl-CoA substrates. A common CoA moiety binding pattern is usually observed in this family, understanding the substrate-binding mechanism would facilitate the rational engineering of crotonases for improved properties. METHODS: We applied X-ray crystallography to investigate a putative enoyl-CoA hydratase/isomerase OdaA in Pseudomonas aeruginosa. Thermal shift assay (TSA) were performed to explore the binding of OdaA with CoA thioester substrates. Furthermore, we performed molecular dynamics (MD) simulations to elucidate the dynamics of its CoA-binding site. RESULTS: We solved the crystal structures of the apo and CoA-bound OdaA. Thermal shift assay (TSA) showed that CoA thioester substrates bind to OdaA with a different degree. MD simulations demonstrated that the C-terminal alpha helix underwent a structural transition and a hinge region would associate with this conformational change. CONCLUSIONS: TSA in combination with MD simulations elucidate that the dynamics of C-terminal alpha helix in CoA-binding, and a hinge region play an important role in conformational change. GENERAL SIGNIFICANCE: Those results help to extend our knowledge about the nature of crotonases and would be informative for future mechanistic studies and industry applications.

3.
J Ethnopharmacol ; 266: 113461, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33039625

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jinmaitong (JMT) is a prescription of Traditional Chinese Medicine, which is composed of ten herbal drugs and two animal drugs. It has long been used for the treatment of diabetic peripheral neuropathy (DPN). AIM OF STUDY: Wnt/ß-catenin pathway is considered as an essential and direct driver of myelinogenesis. This study aims to evaluate the protective effect of JMT against DPN dynamically during a 16-weeks' treatment, and to investigate the underlying mechanism in which the Wnt/ß-catenin pathway is involved. MATERIALS AND METHODS: Diabetic model was induced by single intraperitoneal injection of Streptozotocin (STZ) using male Sprague-Dawley rats. The model rats were divided into five groups and administrated with JMT at three doses (0.437, 0.875, and 1.75 g/kg per day), neurotropin (positive drug, 2.67 NU/kg per day), and placebo (deionized water), respectively, for continuous 8 weeks (n = 9-10), 12 weeks (n = 8-10), or 16 weeks (n = 7-9). Meanwhile, rats in control group were administrated with placebo (n = 10 for 8 weeks, n = 9 for 12 and 16 weeks, respectively). Blood glucose and body weight were monitored every four weeks. Mechanical allodynia was assessed using mechanical withdrawal threshold (MWT) test. The morphological change of sciatic nerves were observed by transmission electron microscope (TEM) and hematoxylin and eosin (HE) stain. The mRNA and protein levels of targeted genes were evaluated by quantitative real time-PCR and western bolt, respectively. Myelin protein zero (MPZ) and mediators involved in Wnt/ß-catenin pathway, such as ß-catenin, glycogen synthase kinase 3ß (GSK-3ß), and WNT inhibitory factor-1 (WIF-1), were compared among different groups after treatment of 8, 12, and 16 weeks, respectively. RESULTS: The mechanical allodynia and peripheral nerve morphology were degenerated in DPN rats over time, and notably improved after JMT-treatment of 12 and 16 weeks. The decreased MPZ level in DPN rats were also significantly amended by JMT. More importantly, we found that the suppressed Wnt/ß-catenin pathway in sciatic nerves of DPN rats was overtly up-regulated by JMT in a time-dependent manner. Among the three doses, JMT at the middle dose showed the best effect. CONCLUSIONS: JMT effectively ameliorated diabetic-induced peripheral neuropathy, which was mediated by the activation of Wnt/ß-catenin signaling pathway. This study provided new perspective to understand the neuroprotective mechanism of JMT.

4.
Water Res ; 188: 116407, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-33065415

RESUMO

Understanding the temporal and spatial roles of nutrient limitation on phytoplankton growth is necessary for developing successful management strategies. Chesapeake Bay has well-documented seasonal and spatial variations in nutrient limitation, but it remains unknown whether these patterns of nutrient limitation have changed in response to nutrient management efforts. We analyzed historical data from nutrient bioassay experiments (1992-2002) and data from long-term, fixed-site water-quality monitoring program (1990-2017) to develop empirical approaches for predicting nutrient limitation in the surface waters of the mainstem Bay. Results from classification and regression trees (CART) matched the seasonal and spatial patterns of bioassay-based nutrient limitation in the 1992-2002 period much better than two simpler, non-statistical approaches. An ensemble approach of three selected CART models satisfactorily reproduced the bioassay-based results (classification rate = 99%). This empirical approach can be used to characterize nutrient limitation from long-term water-quality monitoring data on much broader geographic and temporal scales than would be feasible using bioassays, providing a new tool for informing water-quality management. Results from our application of the approach to 21 tidal monitoring stations for the period of 2007-2017 showed modest changes in nutrient limitation patterns, with expanded areas of nitrogen-limitation and contracted areas of nutrient saturation (i.e., not limited by nitrogen or phosphorus). These changes imply that long-term reductions in nitrogen load have led to expanded areas with nutrient-limited phytoplankton growth in the Bay, reflecting long-term water-quality improvements in the context of nutrient enrichment. However, nutrient limitation patterns remain unchanged in the majority of the mainstem, suggesting that nutrient loads should be further reduced to achieve a less nutrient-saturated ecosystem.

5.
Ann Palliat Med ; 9(5): 3162-3169, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33065782

RESUMO

BACKGROUND: Evaluate the accuracy of IWI predicting weaning in patients with mechanical ventilation greater than 72 hours. METHODS: All patients were divided into two groups, according to FiO2 in the intensive care unit (ICU) with mechanically ventilated for more than 72 hours. Recorded Integrative weaning index (IWI) related indicators in all patients. Evaluate the accuracy of IWI predicting weaning success. RESULTS: Within these 50 patients, 32 of them were weaning successfully, and 18 of the patients failed. Using IWI >45.70 mL/cmH2O breaths/minute/liter as a threshold of predicting successful weaning, the sensitivity is 0.91, and the specificity is 0.83. The AUC of IWI was 0.91. In the group with FiO2 =0.40, 17 patients were successfully liberated from MV, while 8 patients failed. The sensitivity is 0.8235, and specificity is 0.88 using IWI >50.40 mL/cmH2O breath/minute/liter as a threshold for predicting the outcome of weaning. The AUC of IWI was 0.846±0.117. In the FiO2 =0.35 group, 15 patients were successfully liberated from MV, while 10 patients failed. Using IWI >39.33 mL/cmH2O breaths/minute/liter, as a threshold to predict successful weaning, results in a sensitivity of 0.93 and a specificity of 0.90. The AUC of IWI was 0.953±0.395. CONCLUSIONS: Results showed IWI has a significantly higher AUC value compared with other traditional weaning indexes. Hence, it can be a significant predictor for weaning outcomes.

6.
Insects ; 11(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066376

RESUMO

Ecdysteroid titer determines the state of the cell cycle in silkworm (Bombyxmori) metamorphosis. However, the mechanism of this process is unclear. In this study, we demonstrated that the BmFoxO gene participates in the regulation of the cell cycle induced by 20-Hydroxyecdysone (20E) in BmN-SWU1 cells. The 20E blocks the cell cycle in the G2/M phase through the ecdysone receptor (EcR) and inhibits DNA replication. The 20E can promote BmFoxO gene expression. Immunofluorescence and Western blot results indicated that 20E can induce BmFoxO nuclear translocation in BmN-SWU1 cells. Overexpression of the BmFoxO gene affects cell cycle progression, which results in cell cycle arrest in the G0/G1 phase as well as inhibition of DNA replication. Knockdown of the BmFoxO gene led to cell accumulation at the G2/M phase. The effect of 20E was attenuated after BmFoxO gene knockdown. These findings increase our understanding of the function of 20E in the regulation of the cell cycle in B. mori.

7.
BMC Public Health ; 20(1): 1557, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066742

RESUMO

BACKGROUND: Tuberculosis (TB) is one of the major infectious diseases that seriously endanger people's health. In Shandong province, the relationship between the level of economic development and TB incidence has not been studied. This study aims to provide more research basis for the government to prevent and control TB by exploring the impact of different economic factors on TB incidence. METHODS: By constructing threshold regression model (TRM), we described the extent to which different economic factors contribute to TB registered incidence and differences in TB registered incidence among seventeen cities with different levels of economic development in Shandong province, China, during 2006-2017. Data were retrieved from the China Information System for Disease Control and Prevention. RESULTS: Per capita medical expenditure (regression coefficient, -0.0314462; SD, 0.0079305; P > |t|, 0.000) and per capita savings (regression coefficient, 0.0001924; SD, 0.0000566; P > |t|, 0.001) passed the significance test at the level of 1%.They are the two economic indicators that have the greatest impact on TB registered incidence. Through the threshold test, we selected the per capita savings as the threshold variable. In the three stages of per capita savings (<9772.8086 China Yuan(CNY); 9772.8086-33,835.5391 CNY; >33,835.5391 CNY), rural per capita income always has a significant negative impact on the TB registered incidence (The regression coefficients are - 0.0015682, - 0.0028132 and - 0.0022253 respectively. P is 0.007,0.000 and 0.000 respectively.).In cities with good economies, TB registered incidence was 38.30% in 2006 and dropped to 25.10% by 2017. In cities with moderate economies, TB registered incidence peaked in 2008 at 43.10% and dropped to 27.1% by 2017.In poorer cities, TB registered incidence peaked in 2008 at 56.30% and dropped to 28.9% in 2017. CONCLUSION: We found that per capita savings and per capita medical expenditure are most closely related to the TB incidence. Therefore, relevant departments should formulate a more complete medical system and medical insurance policy to effectively solve the problem of "difficult and expensive medical treatment". In order to further reduce the TB incidence, in addition to timely and accurate diagnosis and treatment, it is more important for governments to increase investment in medicine and health care.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33067789

RESUMO

Nanofiltration (NF) membranes show great potential for advanced water treatment, especially for trace organic pollutant removal. The removal efficiency of pharmaceuticals and personal care products (PPCPs) and environmental estrogenic hormones (EEHs) by positively charged hollow fiber NF membranes (PEI-NF) were evaluated. The separation properties were evaluated by changing the operating pressure, temperature, ionic strength, and cation species. A relationship between the physicochemical characteristics of the pharmaceuticals and the NF membrane retention behavior was established. The results showed that the rejection rates of the PEI-NF membrane for the selected PPCPs and EEHs ranged from 81 to ~ 91.26%. For positively (negatively) charged pharmaceutical molecules, the electrostatic repulsion (attraction) effect and steric hindrance were the dominant rejection mechanisms of the PEI-NF membrane. For neutral pharmaceutical molecules, in addition to the size sieving effect, the hydration-induced size increase of hydrophilic substances improved the rejection rates. Both the molecular structure and diffusion coefficient of pharmaceutical molecules influenced their rejection by the PEI-NF membrane to a certain extent. Moreover, the PEI-NF membrane showed a high removal effect for PPCPs and EEHs in water samples from actual tap water plants.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33067864

RESUMO

Gold is the most inert metal and does not react with H 2 to form bulk hydrides. Here, we report the isolation and characterization of a gold nanohydride protected by diphosphine ligands, [Au 22 H 4 (dppo) 6 ] 2+ [dppo = 1,8-bis(diphenylphosphino)octane]. The Au 22 core consists of two Au 11 units bonded by eight Au atoms not coordinated by the diphosphine ligands. The four H atoms are found to bridge the eight uncoordinated Au atoms at the interface. Each Au 11 unit can be viewed as a tetravalent superatom forming four delocalized Au-H-Au bonds, similar to the quadruple bond first discovered in the [Re 2 Cl 8 ] 2- inorganic cluster. The [Au 22 H 4 (dppo) 6 ] 2+ nanohydride is found to lose H atoms over an extended time via H combination (H 2 ), proton (H + ) and hydride (H - ) transfers. This complete repertoire of H-related transformations suggests that the [Au 22 H 4 (dppo) 6 ] 2+ nanohydride is a versatile model catalyst for understanding the mechanisms of chemical reactions involving hydrogen on the surface of gold nanoparticles.

10.
Environ Toxicol ; 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33068063

RESUMO

Oral cancer is a multifactorial cancer that affects millions of peoples worldwide. The current exploration aimed to evaluate the mechanisms that thymoquinone nanoencapsulated carrier and its effects on 7,12-Dimethylbenz[a]anthracene (DMBA) stimulated hamster buccal pouch cancer in Syrian hamster model. Nanocarrier was characterized by SEM, TEM, FTIR analysis. The incidence of tumor, and biochemicals makers was studied through standard methods. The mRNA expression level of inflammatory markers NF-κBp50, NF-κBp65, and PI3K/AKT/mTOR markers in the buccal tissues of control and experimental animals were investigated through RT-PCR analysis. In thymoquinone (TQ) loaded calcium alginate and polyvinyl alcohol carrier (TQ/Ca-alg-PVA) no squamous cell carcinogenesis developed and others moderate dysplasia revealed differentiated form of hyperplasia and keratosis. In biochemical analyses with DMBA + TQ/Ca-alg-PVA (20 mg/kg bw) orally administered hamsters showed restored the antioxidants, detoxification, xenobiotic metabolising enzymes in DMBA induced plasma and oral tissues of hamsters. Further, mRNA expression level of NF-κBp50/p65 and PI3K/AKT/mTOR were upregulated in the DMBA alone painted hamster. In contrast, these expressions were down regulated in orally TQ/Ca-alg-PVA treated experimental animals. This ability more eligible to deregulate the inflammatory and PI3K/AKT/mTOR signaling pathway that proved it suppresses anti-invasion/metastasis activity during hamster buccal pouch carcinogenesis. From this study, we recommended that TQ/Ca-alg-PVA has documented as effective chemopreventive agents, in further many molecular machineries need to study.

11.
Zhongguo Zhen Jiu ; 40(10): 1093-6, 2020 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-33068352

RESUMO

Even though the twelve meridians are connected with five zang and six fu organs separately according to the record in Huangdi Neijing (Yellow Emperor's Internal Classic), the relations of meridians with corresponding zangfu organs are different in characteristics. Through comparing the relative characteristics between meridians and zangfu organs, it is believed that the relationship is established earlier and is quite closer between meridians and five zang organs. There is a great correlation between the disorders of five zang organs and the disorders of meridians. The disorders of five zang organs are commonly treated by the corresponding five-shu points of meridians. The relationship between meridians and six fu organs is established relatively late and the correlation between them is not as closer as that between meridians and five zang organs. The disorders of six fu organs are generally treated by the lower he-sea points. The different characteristics of the correlation between meridians and zangfu organs are relevant with the degree of their integration, the philosophical and cultrual factors and the recognition of ancient masters on zangfu organs.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33047450

RESUMO

Despite the aesthetically appealing structures and tantalizing physical and chemical properties, zigzag hydrocarbon belts and their heteroatom-embedded analogs remain as challenging synthetic targets. We report for the first time the synthesis of diverse O/N-doped zigzag hydrocarbon belts based on selective bridging of the fjords of resorcin[4]arene derivatives through intramolecular S N Ar and Pd-catalyzed intermolecular C-N bond formation reactions. Perfectly preorganized conformations of mono-macrocyclic, half-belt and quasi-belt compounds were revealed to facilitate cyclization reaction to construct heteroatom-linked octahydrobelt[8]arenes. The acquired products gave strained square prism-shaped belt structures in which all six-membered heterocyclic rings adopted unusual boat conformation with alkyl groups being equatorially configured. The unprecedented heteroatom-bearing belts also exhibited different photophysical and redox properties from that of octahydrobelt[8]arene analogs.

13.
Mikrochim Acta ; 187(11): 599, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034765

RESUMO

A tunable plasmon-assisted electrochemiluminescence (ECL) strategy is reported using concave Au nanocubes (Au CBs) for rapidly accelerated fibrosarcoma B-type (BRAF) detection. Concave Au CBs exhibit a strong surface plasmon coupling (SPC) effect between its sharp apexes and edges. The high spectral overlap with graphite phase carbon nitride quantum dots (g-C3N4 QDs) is achieved by tuning surface plasmon absorption peak of the concave Au CBs. It maximizes the SPC effect and enhances the ECL signal of g-C3N4 QDs 3-fold. The SPC effect of Au CBs is twice as high as with Au NPs. We also employed a toehold-mediated strand displacement (TMSD) strategy for sensitive target recycling amplification. Under optimal conditions, this sensor can determine BRAF gene from 1 pM to 1 nM with a detection limit of 3.06 × 10-5 nM (S/N = 3) and RSD 3.67%. With the aid of the TMSD strategy and tunable plasmon-assisted ECL sensing mode, this sensor also exhibits good analytical performance in human serum with satisfactory recovery of 90.2~109%. The proposed strategy provides a promising method to effectively enhance spectral overlap and detect BRAF gene.

14.
Comput Biol Chem ; 89: 107397, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33035753

RESUMO

Qiang-Huo-Sheng-Shi decoction (QHSSD), a classic traditional Chinese herbal formula, which has been reported to be effective in rheumatoid arthritis (RA) and osteoarthritis (OA). However, the concurrent targeting mechanism of how the aforementioned formula is valid in the two distinct diseases OA and RA, which represents the homotherapy-for-heteropathy principle in traditional Chinese medicine (TCM), have not yet been clarified. In the present study, network pharmacology was adopted to analyze the potential molecular mechanism, and therapeutic effective components of QHSSD on both OA and RA. A total of 153 active ingredients in QHSSD were identified, 142 of which associated with 59 potential targets for the two diseases were identified. By constructing the protein-protein interaction network and the compound-target-disease network, 72 compounds and 10 proteins were obtained as the hub targets of QHSSD against OA and RA. The hub genes of ESR1, PTGS2, PPARG, IL1B, TNF, MMP2, IL6, CYP3A4, MAPK8, and ALB were mainly involved in osteoclast differentiation, the NF-κB and TNF signaling pathways. Moreover, molecular docking results showed that the screened active compounds had a high affinity for the hub genes. This study provides new insight into the molecular mechanisms behind how QHSSD presents homotherapy-for-heteropathy therapeutic efficacy in both OA and RA. For the first time, a two-disease model was linked with a TCM formula using network pharmacology to identify the key active components and understand the common mechanisms of its multi-pathway regulation. This study will inspire more innovative and important studies on the modern research of TCM formulas.

15.
Sci Data ; 7(1): 323, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009397

RESUMO

Numerous ecosystem manipulative experiments have been conducted since 1970/80 s to elucidate responses of terrestrial carbon cycling to the changing atmospheric composition (CO2 enrichment and nitrogen deposition) and climate (warming and changing precipitation regimes), which is crucial for model projection and mitigation of future global change effects. Here, we extract data from 2,242 publications that report global change manipulative experiments and build a comprehensive global database with 5,213 pairs of samples for plant production (productivity, biomass, and litter mass) and ecosystem carbon exchange (gross and net ecosystem productivity as well as ecosystem and soil respiration). Information on climate characteristics and vegetation types of experimental sites as well as experimental facilities and manipulation magnitudes subjected to manipulative experiments are also included in this database. This global database can facilitate the estimation of response and sensitivity of key terrestrial carbon-cycling variables under future global change scenarios, and improve the robust projection of global change‒terrestrial carbon feedbacks imposed by Earth System Models.

16.
Medicine (Baltimore) ; 99(41): e22523, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031294

RESUMO

There is scarce evidence that the erythrocyte sedimentation rate (ESR) could efficiently improve the prediction accuracy of the Global Registry of Acute Coronary Events (GRACE) risk score in cases of ST-elevation myocardial infarction (STEMI).A cohort of 1094 STEMI patients undergoing primary percutaneous coronary intervention was retrospectively recruited. Patients were categorized based on the ESR values. Final endpoints included cardiovascular death and major adverse cardiovascular event (MACE) occurrence. The predictive value of combined models with the GRACE score and ESR was assessed by receiver operating characteristic (ROC) analysis, net reclassification improvement (NRI), and integrated discrimination improvement.During the mean follow-up of 23 months, 34 patients died and 190 experienced MACEs, of which 23 patients died in the first year; both endpoints were more frequent in the higher group. The ESR and high-sensitivity C-reactive protein (hs-CRP) were independent risk factors of 1-year cardiovascular death, together with the GRACE score (ESR: hazard ratio = 1.03, P = .006 hs-CRP: hazard ratio = 1.00, P = .001; GRACE: 1.03, P = .012). Although no statistical improvement in the area under the ROC curve was observed in either the GRACE/ESR or the GRACE/hs-CRP model (GRACE/ESR models: 0. 8073 vs GRACE: 0.7714, P = .22; GRACE/ESR models: 0. 7815 vs GRACE: 0.7714, P = .61), the GRACE score and ESR together significantly improved the NRI (0.633; P< .001) compared with the GRACE alone. Regarding the mid-term mortality, adding the ESR to the GRACE score not only improved the NRI (0.8433; P < .001), but also increased the integrated discrimination improvement (0.0509; P = .04).The ESR is an independent risk factor of cardiovascular death and MACE in STEMI patients receiving primary percutaneous coronary intervention. The ESR comparatively enhanced the predictive values of the prognostic model, including the GRACE risk score.

17.
J Mol Model ; 26(11): 298, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034751

RESUMO

A series of energetic compounds derived from substituted oxadiazole molecules which were theoretically proved to have π-π stacking crystal structure using NIC method and QTAIM theory were designed and investigated theoretically as novel high-performance insensitive energetic materials. The heats of formation (HOFs) and detonation parameters were predicted based on Kamlet-Jacobs equations and Born-Haber cycle. All energetic compounds and derivatives were calculated at DFT-B3PW91/6-31G++(d,p) level and exhibited ideal oxygen balance (OB%) (- 19.50~15.68), positive heats of formation (424.0~957.4 kJ/mol), and pleasant crystal density (1.707~1.901 g/cm3). The predicted results revealed that detonation performances of some designed molecules are equal to traditional energetic materials while they are more stable and insensitive that can be considered to have potential synthesis and application value. Graphical abstract BRIEFS Three energetic molecules that proved may have a π-π stacking crystal structure and its derivatives were designed and investigated theoretical as novel high-performance insensitive energetic materials. The most of compounds exhibited positive solid phase heat of formation, idea oxygen balance and structural stability.

18.
Chemistry ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034923

RESUMO

Continuous-flow multi-step synthesis takes the advantages of microchannel flow chemistry and may transform the conventional multi-step organic synthesis by using integrated synthetic systems. To realize the goal, however, innovative chemical methods and techniques are urgently required to meet the significant remaining challenges. In the past years, by using green reactions, telescoped chemical design and/or novel in-line separation techniques, major and rapid advancement has been made in this direction. This minireview summarize the most recent reports (2017-) on continuous-flow synthesis of functional molecules. Particularly, several complex active pharmaceutical ingredients (APIs) have been prepared by the continuous-flow approach. Key technologies to the successes and remaining challenges are discussed. These results exemplified the feasibility of using modern continuous-flow chemistry for complex synthetic targets, and bode well for the future development of integrated, automated artificial synthetic systems.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33027899

RESUMO

Using Fishbein's multi-attribute model, this paper proposes that the impact of socio-demographic and psychosocial factors on local residents' overall attitude toward shale gas exploitation (SGE) is mediated by their risk and benefit perceptions. The proposition has been validated with the generalized structural equation modeling approach with a cross-sectional dataset of 825 residents from China's Fuling shale gas field. Results indicate that the influence of benefit perception on residents' overall attitude outweighs that of risk perception. Moreover, residents' perceived fairness, affective feeling, and trust in regulatory agencies have positive influences on their overall attitude, primarily via their risk and benefit perceptions, in decreasing order of influences. Finally, we also find that residents' attitudes have been significantly influenced by their socio-demographic factors, including age, residential area, and political ideology. Thus, our study extends the literature with theoretical and empirical models by exploring the influences factors of local residents' attitudes toward SGE, and results from our empirical survey provide insight into policy design to promote the acceptance of SGE.

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