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Olefin industry as a vital part in economic development is facing a problem of high CO2 emission. In this work, for the global and China's olefin industry under different development scenario, the carbon emission is predicted after the revealing of carbon footprint in different olefin routes. The results show that the carbon footprint of the natural gas liquids (NGLs)-derived route is highly lower than that of the oil- and coal-derived routes. The carbon emission from the global olefin industry in 2015 is 553 million ton CO2 (MtCO2). In 2030, it will be ranged between 739 and 924 MtCO2 under different scenarios. Under sustainable development scenario, 15% reduction space is existed, whereas 6% growth is observed under the hybrid-development scenario compared to the business-as-usual situation. In the case of China, its carbon emission is 120 MtCO2 in 2015. Its potential carbon emission in 2030 will increase to 264-925 MtCO2, depending on the rest new capacity from low-carbon or high-carbon routes. The large gap implies the significant influence of the development route choice. However, if most new capacity is from the existed planned olefin projects, the carbon emission will be ranged between 390 and 594 MtCO2. Finally, the low-carbon roadmaps as well as polices are proposed for sustainable development of olefin industry.
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Dióxido de Carbono , Carbono , Dióxido de Carbono/análise , Carbono/análise , Alcenos , Carvão Mineral , Gás Natural , China , Desenvolvimento EconômicoRESUMO
Pulses, as a sustainable source of nutrients, are an important choice for human diets, but vast quantities of seed coats generated in pulses processing are usually discarded or used as low-value ruminant feed. It has been demonstrated that pulses seed coats are excellent sources of dietary nutrients and phytochemicals with potential health benefits. With growing interest in the sustainable use of resources and the circular economy, utilization of pulses seed coats to recover these valuable components is a core objective for their valorization and an important step toward agricultural sustainability. This review comprehensively provides a comprehensive insight on the nutritional and phytochemical profiles presented in pulses seed coats and their health benefits obtained from the findings of in vitro and in vivo studies. Furthermore, in the food industry, pulses seed coats can be acted as potential food ingredients with nutritional, antioxidant and antimicrobial characteristics or as the matrix or active components of films for food packaging and edible coatings. A better understanding of pulses seed coats may provide a reference for increasing the overall added value and realizing the pulses' sustainable diets.
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Anti-Infecciosos , Sementes , Humanos , Sementes/química , Antioxidantes/análise , Compostos Fitoquímicos/análise , Indústria Alimentícia , Anti-Infecciosos/análiseRESUMO
Gamma-aminobutyric acid (GABA) is a naturally occurring potential bioactive compound present in plants, microorganisms, animals, and humans. Especially, as a main inhibitory neurotransmitter in the central nervous system, GABA possesses a broad spectrum of promising bioactivities. Thus, functional foods enriched with GABA have been widely sought after by consumers. However, the GABA levels in natural foods are usually low, which cannot meet people's demand for health effects. With the increasing public awareness on the food securities and naturally occurring processes, using enrichment technologies to elevate the GABA contents in foods instead of exogenous addition can enhance the acceptability of health-conscious consumers. Herein, this review provides a comprehensive insight on the dietary sources, enrichment technologies, processing effects of GABA, and its applications in food industry. Furthermore, the various health benefits of GABA-enriched foods, mainly including neuroprotection, anti-insomnia, anti-depression, anti-hypertensive, anti-diabetes, and anti-inflammatory are also summarized. The main challenges for future research on GABA are related to exploring high GABA producing strains, enhancing the stability of GABA during storage, and developing emerging enrichment technologies without affecting food quality and other active ingredients. A better understanding of GABA may introduce new windows for its application in developing functional foods.
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BACKGROUND: Pediatric pulmonary hypertension (PH) is a serious and rare disease that is often derived from genetic mutations. Kabuki syndrome (KS) is a chromosomal abnormality disease that has its origin in the mutation of lysine methyltransferase 2D(KMT2D). Recent evidence has shown that KMT2D mutations are associated with pediatric pulmonary disorders. However, the relationship between the clinical courses of PH and the KMT2D mutation is reported in extremely few cases. Therefore, in this paper, a case was presented and previous literature was reviewed for better understanding of the correlation between pediatric PH and KMT2D mutations. CASE PRESENTATION: A 3-year-old girl was transferred to our center for severe cough, shortness of breath, fatigue and fever. Physical examination revealed facial deformities and growth retardation. Echocardiography showed a small atrial septal defect (ASD), and right heart catheterization indicated a significant increase in pulmonary vascular pressure and resistance. The genetic test suggested that she had a KMT2D gene mutation. The patient was finally diagnosed with KS. She was given targeted drugs to reduce pulmonary vascular pressure, but the effect was unsatisfactory. CONCLUSIONS: KS can be complicated with multiple organ malformations and dysfunction. With the progress of next generation sequencing, an increasing number of new phenotypes related to KMT2D mutations have been reported. A bold hypothesis is proposed in this article, that is, PH may be a new phenotype associated with KMT2D mutations. It is suggested that KS and PH should be differentiated from each other to avoid delayed diagnosis and treatment in clinical practice. There is no specific drug for KS treatment. The prognosis of children with inherited PH is usually poor, and lung transplantation may increase their survival rates.
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Anormalidades Múltiplas , Hipertensão Pulmonar , Humanos , Feminino , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/genética , Fenótipo , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Testes GenéticosRESUMO
Lower olefins-generally referring to ethylene, propylene and butylene-are basic carbon-based building blocks that are widely used in the chemical industry, and are traditionally produced through thermal or catalytic cracking of a range of hydrocarbon feedstocks, such as naphtha, gas oil, condensates and light alkanes. With the rapid depletion of the limited petroleum reserves that serve as the source of these hydrocarbons, there is an urgent need for processes that can produce lower olefins from alternative feedstocks. The 'Fischer-Tropsch to olefins' (FTO) process has long offered a way of producing lower olefins directly from syngas-a mixture of hydrogen and carbon monoxide that is readily derived from coal, biomass and natural gas. But the hydrocarbons obtained with the FTO process typically follow the so-called Anderson-Schulz-Flory distribution, which is characterized by a maximum C2-C4 hydrocarbon fraction of about 56.7 per cent and an undesired methane fraction of about 29.2 per cent (refs 1, 10, 11, 12). Here we show that, under mild reaction conditions, cobalt carbide quadrangular nanoprisms catalyse the FTO conversion of syngas with high selectivity for the production of lower olefins (constituting around 60.8 per cent of the carbon products), while generating little methane (about 5.0 per cent), with the ratio of desired unsaturated hydrocarbons to less valuable saturated hydrocarbons amongst the C2-C4 products being as high as 30. Detailed catalyst characterization during the initial reaction stage and theoretical calculations indicate that preferentially exposed {101} and {020} facets play a pivotal role during syngas conversion, in that they favour olefin production and inhibit methane formation, and thereby render cobalt carbide nanoprisms a promising new catalyst system for directly converting syngas into lower olefins.
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Alcenos/síntese química , Monóxido de Carbono/química , Carbono/química , Carvão Mineral , Cobalto/química , Hidrogênio/química , Nanoestruturas/química , Gás Natural , Biomassa , Catálise , Metano/síntese química , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , PressãoRESUMO
BACKGROUND: The aim of this study was to evaluate anterior teeth movement with different archwire planes and archwire sizes during space closure with and without miniscrew in sliding mechanics. METHODS: A 3D finite element method was applied to simulate anterior teeth retraction with and without miniscrew and power arm. Initial displacements and pressure stresses of periodontal tissue in anterior teeth were calculated after the teeth were applied with retraction forces with different archwire planes and archwire sizes. RESULTS: High archwire plane showed better torque control of anterior teeth in both sliding mechanics. With intramaxillary retraction, anterior teeth showed lingual tipping and extrusion movement, whereas larger-size archwires did not reduce it. In miniscrew sliding mechanics, anterior teeth showed labial tipping and intrusion movement. Compared with intramaxillary retraction, the retraction force produced less pressure stress on periodontal tissue in miniscrew sliding mechanics with long power arm. CONCLUSIONS: Higher archwire plane is conducive to anterior teeth torque control. In order to achieve the bodily movement of the anterior teeth during space closure, it is more important to choose the appropriate method (miniscrew sliding mechanics with long power arm), instead of increasing the size of the archwire.
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Ortodontia , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Incisivo , Fios Ortodônticos , Técnicas de Movimentação Dentária/métodosRESUMO
PURPOSE: Our recent study has reported that whole mung bean showed better beneficial effects on high-fat diet (HFD)-induced obesity and gut microbiota disorders when compared with the decorticated mung bean at the same intervention dose level, suggesting that the mung bean seed coat (MBC) may play a crucial role in its health benefits. This study aims to investigate whether MBC has beneficial benefits on the prevention of HFD-induced obesity and the modulation of gut microbiota in mice when it was supplemented in HFD. METHODS: Herein, male C57BL/6 J mice were fed with normal control diet, HFD, and HFD supplemented with MBC (3-6%, w/w) for 12 weeks. The changes in physiological, histological, biochemical parameters, serum endotoxin, proinflammatory cytokines, and gut microbiota composition of mice were determined to assess the ability of MBC to alleviate HFD-induced obesity and modulate gut microbiota disorders in mice. RESULTS: MBC supplementation exhibited significant reductions in the HFD-induced adiposity, fat accumulation, serum lipid levels, lipopolysaccharide, and proinflammatory cytokines concentrations (P < 0.05), which was accompanied by improvements in hepatic steatosis and adipocyte size. Especially, the elevated fasting blood glucose and insulin resistance were also significantly improved by MBC supplementation (P < 0.05). Furthermore, high-throughput sequencing of the 16S rRNA gene revealed that MBC could normalize HFD-induced gut microbiota dysbiosis. MBC not only could promote the bloom of Akkermansia, but also restore several HFD-dependent taxa (Blautia, Ruminiclostridium_9, Bilophila, and unclassified_f_Ruminococcaceae) back to normal status, co-occurring with the decreases in obesity-related indices. CONCLUSIONS: This study provides evidence that MBC may be mainly responsible for the beneficial effects of whole mung bean on preventing the HFD-induced changes, thus enlarging the application value of MBC.
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Microbioma Gastrointestinal , Vigna , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/prevenção & controle , RNA Ribossômico 16S , SementesRESUMO
Internet hospitals, as a new forum for doctors to conduct diagnosis and treatment activities based on the internet, are emerging in China and have become integral to the development of the medical field in conjunction with increasing reforms and policies in China's medical and health system. Here, we take the Internet Hospital of the First Affiliated Hospital, Zhejiang University (FAHZU Internet Hospital) as an example to discuss the operations and functional positioning of developing internet hospital medical services in relation to physical hospitals. This viewpoint considers the platform operation, management, and network security of FAHZU Internet Hospital, and summarizes the advantages and limitations in the operation to provide a reference for other areas with interest in developing internet hospitals.
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Telemedicina , China , Hospitais , Humanos , InternetRESUMO
PURPOSE: Obesity, a strong risk factor for metabolic disorder, has become a major impediment for public health globally. The objective of this study was to assess the anti-obesity effect of mung bean, and the relationship between the gut microbiota modulatory effects of mung bean and the prevention of obesity. METHODS: Thirty-two four-week-old male C57BL/6 J mice were divided into four groups: normal chow diet (NCD), high-fat diet (HFD), a high-fat diet supplemented with 30% whole mung bean flour (HFD-WMB), and a high-fat diet supplemented with 30% decorticated mung bean flour (HFD-DMB). The ability of a mung bean-based diet to combat obesity-related metabolic disorder was determined by assessing the changes in physiological, histological, biochemical parameters, and gut microbiota composition of mice with HFD-induced obesity at 12 weeks. RESULTS: Both of WMB and DMB supplementation can effectively alleviate HFD-induced lipid metabolic disorders, which was accompanied by a reduction in hepatic steatosis. However, the only supplementation with WMB significantly reduced HFD-induced body weight gain, fat accumulation, and adipocyte size, and ameliorated the glucose tolerance and insulin resistance by sensitizing insulin action. Furthermore, high-throughput pyrosequencing of 16S rRNA revealed that WMB and DMB supplementation could normalize HFD-induced gut microbiota dysbiosis. Especially, WMB and DMB supplementation significantly promoted the relative abundance of Akkermansia and Bifidobacterium, respectively, and both of them significantly restored the relative abundance of several HFD-dependent taxa back to normal status in this study. Spearman's correlation analysis revealed that those genera are closely correlated with obesity-related indices. CONCLUSIONS: Although WMB showed better beneficial effects on HFD-induced obesity in comparison with DMB, DMB still retained some health benefits. Moreover, the alleviation of HFD-induced changes by mung bean supplementation was, at least, partially conciliated by structural modulation of gut microbiota.
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Microbioma Gastrointestinal , Vigna , Animais , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade , RNA Ribossômico 16SRESUMO
High-molecular-weight glutenin subunits (HMW-GSs) are storage proteins present in the starchy endosperm cells of wheat grain. Encoding the synthesis of HMW-GS, the Glu-1 loci located on the long arms of group 1 chromosomes of the hexaploid wheat (1A, 1B, and 1D) present multiple allelism. In hexaploid wheat cultivars, almost all of them express 3 to 5 HMW-GSs and the 1Ay gene is always silent. Though HMW-GSs are the minor components in gluten, they are crucial for dough properties, and certain HMW-GSs make more positive contributions than others. The HMW-GS acts as a "chain extender" and provides a disulfide-bonded backbone in gluten network. Hydrogen bonds mediated by glutamine side chains are also crucial for stabilizing the gluten structure. In most cases, HMW-GSs with additional or less cysteines are related to the formation of relatively more or less interchain disulfide bonds and HMW-GSs also affect the gluten secondary structures, which in turn impact the end use qualities of dough.
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Endosperma/metabolismo , Glutens/genética , Glutens/metabolismo , Triticum/metabolismo , Endosperma/genética , Glutens/química , Peso Molecular , Triticum/genéticaRESUMO
BACKGROUND: Because of its high nutritional value and good sensory properties, fragrant rice is very popular all over the world. The aroma and taste of fragrant rice play an essential role in its sensory properties. However, there has been a lack of studies on flavor changes in fragrant rice during storage. RESULTS: Hexanal, nonanal, benzaldehyde, hexadecanoic acid, and methyl ester, were identified as aroma-active compounds in fresh fragrant rice. After storage, more than 100 volatile compounds can be identified. The results indicated that, at high-temperature storage, volatile compounds such as aldehydes, ketones, and furans increased, which led to a deterioration in rice quality. Marker compounds of flavor deterioration, methyl palmitate, 2-methyl-propanoic acid, and 3-hydroxy-2,2,4-trimethylpentyl ester, were determined by principal component analysis. In addition to threonine and proline, the other 14 amino acids contributed to the taste of fragrant rice during storage. Sucrose is the only main contributor to the sweetness of Daohuaxiang 2, whereas glucose and fructose had a little sweet taste contribution during storage. The electronic nose (e-nose) and the electronic tongue (e-tongue) could distinguish samples with different storage conditions. CONCLUSION: Different storage conditions can cause flavor differences in fragrant rice. Especially under high-temperature storage, volatile compounds such as aldehydes, ketones, and furans increase, which is an important reason for the deterioration in the quality of fragrant rice during storage. © 2020 Society of Chemical Industry.
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Aromatizantes/química , Oryza/química , Compostos Orgânicos Voláteis/química , Nariz Eletrônico , Armazenamento de Alimentos/instrumentação , Armazenamento de Alimentos/métodos , Temperatura Alta , Humanos , Odorantes/análise , PaladarRESUMO
Cryptotanshinone (CPT) is an efficacious acne treatment, while niosomal hydrogel is a known effective topical drug delivery system that produces a minimal amount of irritation. Three-dimensional (3D) printing technologies have the potential to improve the field of personalized acne treatment. Therefore, this study endeavored to develop a 3D-printed niosomal hydrogel (3DP-NH) containing CPT as a topical delivery system for acne therapy. Specifically, CPT-loaded niosomes were prepared using a reverse phase evaporation method, and the formulation was optimized using a response surface methodology. In vitro characterization showed that optimized CPT-loaded niosomes were below 150 nm in size with an entrapment efficiency of between 67 and 71%. The CPT-loaded niosomes were added in a dropwise manner into the hydrogel to formulate CPT-loaded niosomal hydrogel (CPT-NH), which was then printed as 3DP-CPT-NH with specific drug dose, shape, and size using an extrusion-based 3D printer. The in vitro release behavior of 3DP-CPT-NH was found to follow the Korsmeyer-Peppas model. Permeation and deposition experiments showed significantly higher rates of transdermal flux, Q24, and CPT deposition (p < 0.05) compared with 3D-printed CPT-loaded conventional hydrogel (3DP-CPT-CH), which did not contain niosomes. In vivo anti-acne activity evaluated through an acne rat model revealed that 3DP-CPT-NH exhibited a greater anti-acne effect with no skin irritation. Enhanced skin hydration, wide inter-corneocyte gaps in the stratum corneum and a disturbed lipid arrangement may contribute towards the enhanced penetration properties of CPT. Collectively, this study demonstrated that 3DP-CPT-NH is a promising topical drug delivery system for personalized acne treatments.
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Acne Vulgar/tratamento farmacológico , Hidrogéis/química , Fenantrenos/administração & dosagem , Administração Cutânea , Animais , Sistemas de Liberação de Medicamentos/métodos , Lipossomos/farmacologia , Masculino , Tamanho da Partícula , Fenantrenos/química , Impressão Tridimensional , Ratos , Pele/metabolismo , Absorção CutâneaRESUMO
Context: Curcumin, a polyphenolic compound extracted from the rhizome of the tropical plant Curcuma longa L. (Zingiberaceae), has been considered as a cancer chemopreventive drug by American National Cancer Institute.Objective: To examine the effect of curcumin on acute monocytic leukaemia SHI-1 cells in vivo.Materials and methods: The SHI-1 cells (1 × 106 cells in 0.1 mL PBS) were injected subcutaneously into the right flanks of the female SCID mice. Curcumin dissolved in olive oil (15 and 30 mg/kg) was administered (i.p.) to mice once a day for 15 days while the control group received olive oil injection. Tumour proliferation and apoptosis were examined by PCNA, TUNEL and cleaved caspase-3 staining. The expression of MAPK, NF-κB, MMP9, MMP2 and vimentin were confirmed by RT-PCR, immunohistochemistry or western blotting.Results: Administration of curcumin significantly inhibited tumour growth, as the tumour weight decreased from 0.67 g (control) to 0.47 g (15 mg/kg) and 0.35 g (30 mg/kg). Curcumin inhibited the expression of PCNA and increased the degree of TUNEL and cleaved caspase-3 staining in tumour tissue. The results of western blotting showed that curcumin treatment inhibited NF-κB and ERK signalling while activating p38 and JNK. Moreover, curcumin attenuated the mRNA transcription and protein expression of MMP2 and MMP9. Curcumin also suppressed the level of vimentin.Discussion and conclusions: Our study demonstrates that curcumin can inhibit the growth and invasion of human monocytic leukaemia in vivo, suggesting the possible use of curcumin for anti-metastasis in leukaemia and the value of determining its unique target.
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Antineoplásicos Fitogênicos/farmacologia , Curcumina/farmacologia , Leucemia Monocítica Aguda/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Curcumina/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , Leucemia Monocítica Aguda/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos SCID , NF-kappa B/metabolismo , Invasividade Neoplásica , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The aim of this study was to investigate the in vitro starch digestibility and estimated glycemic index (eGI) of mung bean (Vigna radiata L.) as affected by endogenous proteins and lipids, and exogenous heat-processing methods. Results showed that the in vitro starch digestibility and eGI were significantly increased after the removal of protein, lipid, or both (P < 0.05). Moreover, the effects of endogenous proteins and lipids on the in vitro starch digestibility and eGI of mung bean followed the order: both protein and lipid removal > protein removal > lipid removal. In addition, heat-processing could make the slowly digestible starch and resistant starch convert to the rapidly digestible starch. The effects of different exogenous heat-processing methods on in vitro starch digestibility and eGI in the present study showed the following order: germination combined with cooking > high-pressure cooking > extrusion cooking > ordinary cooking. This study provided a crucial reference for the human with potential hyperglycemia to choose mung bean treated with ordinary cooking and without further protein and/or lipid removal.
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Amido , Vigna , Digestão , Índice Glicêmico , Temperatura Alta , Humanos , LipídeosRESUMO
Coal-based olefin (CTO) industry as a complement of traditional petrochemical industry plays vital role in China's national economic development. However, high CO2 emission in CTO industry is one of the fatal problems to hinder its development. In this work, the carbon emission and mitigation potentials by different reduction pathways are evaluated. The economic cost is analyzed and compared as well. According to the industry development plan, the carbon emissions from China's CTO industry will attain 189.43 million ton CO2 (MtCO2) and 314.11 MtCO2 in 2020 and 2030, respectively. With the advanced technology level, the maximal carbon mitigation potential could be attained to 15.3% and 21.9% in 2020 and 2030. If the other optional mitigation ways are combined together, the carbon emission could further reduce to some extent. In general, the order of mitigation potential is followed as: feedstock alteration by natural gas > CO2 hydrogenation with renewable electricity applied > CCS technology. The mitigation cost analysis indicates that on the basis of 2015 situation, the economic penalty for feedstock alteration is the lowest, ranged between 186 and 451 CNY/tCO2, and the cost from CCS technology is ranged between 404 and 562 CNY/tCO2, which is acceptable if the CO2 enhanced oil recovery and carbon tax are considered. However, for the CO2 hydrogenation technology, the cost is extremely high and there is almost no application possibility at present.
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Alcenos/química , Dióxido de Carbono , Carbono , Carvão Mineral , Poluição Ambiental/prevenção & controle , Indústria Química , China , Poluição Ambiental/economiaRESUMO
A multimodal cancer therapeutic nanoplatform is reported. It demonstrates a promising approach to synergistically regulating the tumor microenvironment. The combination of intracellular reactive oxygen species (ROS) generated by irradiation of photosensitizer and endoplasmic reticulum (ER) stress induced by 2-deoxy-glucose (2-DG) has a profound effect on necrotic or apoptotic cell death. Especially, targeting metabolic pathway by 2-DG is a promising strategy to promote the effect of photodynamic therapy and chemotherapy. The nanoplatform can readily release its cargoes inside cancer cells and combines the advantages of ROS-sensitive releasing chemotherapeutic drugs, upregulating apoptosis pathways under ER stress, light-induced generation of cytotoxic ROS, achieving tumor accumulation, and in vivo fluorescence imaging capability. This work highlights the importance of considering multiple intracellular stresses as design parameters for nanoscale functional materials in cell biology, immune response, as well as medical treatments of cancer, Alzheimer's disease, etc.
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Antineoplásicos/farmacologia , Desoxiglucose/farmacologia , Estresse do Retículo Endoplasmático , Luz , Microambiente Tumoral/efeitos dos fármacos , Apoptose , Terapia Combinada , Humanos , Cinética , Células MCF-7 , Nanomedicina , Necrose , Fagocitose , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de OxigênioRESUMO
We have developed an iron-catalyzed direct olefination for enaminone synthesis, with saturated ketones as a source of olefins. This direct ketone ß-functionalization reaction has readily available starting materials and a wide range of substrates and requires mild reaction conditions.
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Nanoscale design of nanofillers and interfacial architecture are vital to achieve high-capacity and high-energy-conversion efficiency poly(vinylidene fluoride) [(PVDF)-based] nanocomposite materials for vast potential applications in modern electronic devices and electric power systems. Using traditional methods, the addition of ceramic nanoparticles can only produce one type of interface between the nanoparticles and this matrix, achieving an enhanced dielectric constant and energy density at the expense of the charge-discharge efficiency. Herein, we demonstrate a novel class of cross-linking nanofiller system, poly(vinylidene fluoride-chlorotrifluoroethylene)/γ-methacryloylpropyl trimethoxysilane@BaTiO3 [P(VDF-CTFE)/MPS@BT]. This novel approach can not only provide the interfaces between the nanoparticle and the matrix, but also scale down the size of crystalline domains, which results in producing more additional interfaces between the crystalline and amorphous phases to achieve an improved discharged energy density. Remarkably, the smaller crystalline domains, which were characterized by XRD and FTIR spectroscopy, could be beneficial for improving the dipole switchability from the polar phases to non-polar phases during the charge-discharge cycles, leading to unprecedented charge-discharge efficiency. Furthermore, the addition of MPS@BT NPs can regulate two stages of the discharge rate. The early discharge process can be accelerated, while the following stage is obviously delayed. The simplicity of the hierarchical interfacial engineering method provides a promising path to design ferroelectric polymer nanocomposites for dielectric capacitor applications.
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High-capacity or high-power-density capacitors are being actively investigated for portable electronics, electric vehicles, and electric power systems. We describe the filler system in dielectric nanocomposites with a small loading of Au nanorods [NRs] to elucidate the mechanism of interfacial crystallization behavior including the crystallization kinetics, and crystalline morphology and structure, and to investigate the intrinsic causes for concurrent great improvements in the dielectric constant and energy density in the nanocomposite system. Remarkly, at high crystallization temperature, the addition of Au NRs, which are used as heterogeneous nucleators, can reduce the nucleation barrier, resulting in accelerating the crystallization rate. However, the crystallization rate slows down at low temperatures because the addition of Au NRs limited the mobility of poly(vinylidene fluoride-chlorotrifluoroethylene) [P(VDF-CTFE)] chains, and thus enhanced the diffusion barrier. Furthermore, the addition of NRs has a huge impact on the crystalline morphology and structure which changes from large paraelectric α-phase spherulites with TGTG' conformations into minor ferroelectric γ-phase spherulites with T3GT3G' conformations, and also produces more exogenous interfaces between the lamellar crystals and amorphous regions, resulting in a higher dielectric constant and higher electric energy density in P(VDF-CTFE)/Au NRs nanocomposites. Our approach provides a facile and straightforward way to design or understand PVDF-based polymers for their practical applications in high-energy-density capacitors.