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1.
Nature ; 629(8013): 798-802, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599238

RESUMO

Compared to polycrystalline semiconductors, amorphous semiconductors offer inherent cost-effective, simple and uniform manufacturing. Traditional amorphous hydrogenated Si falls short in electrical properties, necessitating the exploration of new materials. The creation of high-mobility amorphous n-type metal oxides, such as a-InGaZnO (ref. 1), and their integration into thin-film transistors (TFTs) have propelled advancements in modern large-area electronics and new-generation displays2-8. However, finding comparable p-type counterparts poses notable challenges, impeding the progress of complementary metal-oxide-semiconductor technology and integrated circuits9-11. Here we introduce a pioneering design strategy for amorphous p-type semiconductors, incorporating high-mobility tellurium within an amorphous tellurium suboxide matrix, and demonstrate its use in high-performance, stable p-channel TFTs and complementary circuits. Theoretical analysis unveils a delocalized valence band from tellurium 5p bands with shallow acceptor states, enabling excess hole doping and transport. Selenium alloying suppresses hole concentrations and facilitates the p-orbital connectivity, realizing high-performance p-channel TFTs with an average field-effect hole mobility of around 15 cm2 V-1 s-1 and on/off current ratios of 106-107, along with wafer-scale uniformity and long-term stabilities under bias stress and ambient ageing. This study represents a crucial stride towards establishing commercially viable amorphous p-channel TFT technology and complementary electronics in a low-cost and industry-compatible manner.

2.
Water Sci Technol ; 86(5): 1108-1121, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36358049

RESUMO

In order to explore the effect of influent PO43--P concentration on the relationship of phosphorus remove performance and sludge settleability, three sequencing batch reactors (SBRs) operated as anaerobic/aerobic mode were used to treat wastewater with different PO43--P concentrations (same COD), and the organic loading rate (OLR) was changed through adjusting the anaerobic (aerobic) duration. The sludge settleability, nutrients removal, and microorganism species were investigated. The results showed that when the influent PO43--P were 4.3 mg·L-1 and 8.6 mg·L-1, increasing the OLR through decreasing aerobic duration could significantly improve sludge settleability, while decreasing anaerobic duration could not. It was found that increase the OLR could promote the denitrification compete for carbon sources with phosphorus release process by inhibiting the accumulation of NO2--N, leading to the decrease of phosphorus removal ability. When the influent PO43--P was 17.2 mg·L-1, sufficient nitrification was beneficial to enrich denitrifying phosphorus accumulating bacteria (DPAO), and the activities of Thauera and Flavobacterium (DPAO) were stronger. Therefore, increasing influent PO43--P concentration and reducing aerobic duration could help phosphorus accumulating bacteria (PAO) compete with denitrification for COD and enrich DPAO, thus reducing carbon source consumption.


Assuntos
Desnitrificação , Esgotos , Esgotos/microbiologia , Eliminação de Resíduos Líquidos , Reatores Biológicos/microbiologia , Nitrogênio , Nitrificação , Fósforo , Águas Residuárias , Carbono , Nutrientes , Bactérias
3.
Nat Commun ; 13(1): 1741, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365628

RESUMO

Despite the impressive development of metal halide perovskites in diverse optoelectronics, progress on high-performance transistors employing state-of-the-art perovskite channels has been limited due to ion migration and large organic spacer isolation. Herein, we report high-performance hysteresis-free p-channel perovskite thin-film transistors (TFTs) based on methylammonium tin iodide (MASnI3) and rationalise the effects of halide (I/Br/Cl) anion engineering on film quality improvement and tin/iodine vacancy suppression, realising high hole mobilities of 20 cm2 V-1 s-1, current on/off ratios exceeding 107, and threshold voltages of 0 V along with high operational stabilities and reproducibilities. We reveal ion migration has a negligible contribution to the hysteresis of Sn-based perovskite TFTs; instead, minority carrier trapping is the primary cause. Finally, we integrate the perovskite TFTs with commercialised n-channel indium gallium zinc oxide TFTs on a single chip to construct high-gain complementary inverters, facilitating the development of halide perovskite semiconductors for printable electronics and circuits.

4.
Am J Chin Med ; 50(3): 799-815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35300568

RESUMO

Stroke has become a major cause of death and disability worldwide. The cellular recycling pathway autophagy has been implicated in ischemia-induced neuronal changes, but whether autophagy plays a beneficial or detrimental role is controversial. Hydroxysafflor Yellow A (HSYA), a popular herbal medicine, is an extract of Carthamus tinctorius and is used to treat ischemic stroke (IS) in China. HSYA has been shown to prevent cardiovascular and cerebral ischemia/reperfusion injury in animal models. However, the specific active ingredients and molecular mechanisms of HSYA in IS remain unclear. Here, we investigated the effect of HSYA treatment on autophagy in a rat model of IS. IS was induced in rats by middle cerebral artery occlusion. Rats were treated once daily for 3 days with saline, HYSA, or the neuroprotective agent Edaravone. Neurobehavioral testing was performed on days 1, 2, and 3 post-surgery. Brains were removed on day 3 post-surgery for histological evaluation of infarct area, morphology, and for qRT-PCR and western blot analysis of the expression of the autophagy factor LC3 and the signaling molecules HIF-1[Formula: see text], BNIP3, and Notch1. Molecular docking studies were performed in silico to predict potential interactions between HSYA and LC3, HIF-1[Formula: see text], BNIP3, and Notch1 proteins. The result showed that HSYA treatment markedly alleviated IS-induced neurobehavioral deficits and reduced brain infarct area and tissue damage. HSYA also significantly reduced hippocampal expression levels of LC3, HIF-1[Formula: see text], BNIP3, and Notch1. The beneficial effect of HSYA was generally superior to that of Edaravone. Molecular modeling suggested that HSYA may bind strongly to HIF-1[Formula: see text], BNIP3, and Notch1 but weakly to LC3. In conclusion, HSYA inhibits post-IS autophagy induction in the brain, possibly by suppressing HIF-1[Formula: see text], BNIP3 and Notch1. HSYA may have utility as a post-IS neuroprotective agent.


Assuntos
Isquemia Encefálica , Chalcona , AVC Isquêmico , Fármacos Neuroprotetores , Animais , Autofagia , Isquemia Encefálica/patologia , Chalcona/análogos & derivados , Chalcona/farmacologia , Chalcona/uso terapêutico , Edaravone/farmacologia , Fator 1 Induzível por Hipóxia , AVC Isquêmico/tratamento farmacológico , Proteínas de Membrana/genética , Proteínas Mitocondriais/farmacologia , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/farmacologia , Quinonas/farmacologia , Ratos , Receptor Notch1/genética
5.
Nat Prod Commun ; 17(2): 1934578X221075075, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35136386

RESUMO

Objective: To predict the mechanism of Shengmai Injection (SMI) in the acute treatment of COVID-19 by network pharmacology and molecular docking. Methods: Search the compounds in the Traditional Chinese Medicine Systems Pharmacology (TCMSP), and screen them by Drug-like properties (DL) and Oral bioavailability (OB); Using PharmMapper database and GeneCards database to collect compounds targets and COVID-19 targets, and using UniProt database to standardize the names of target genes; Using DAVID database for KEGG pathway annotation and GO bioinformatics analysis; Using Cytoscape 3.8.2 software and STRING 10.5 database to construct "Component-Target-Pathway" network and Protein-Protein Interaction network (PPI); Using molecular docking to predict the binding ability of key compounds and key proteins. Results: A total of 34 active components, 38 core targets and 180 signaling pathways were screened out. The results of molecular docking showed that Schisantherin A and Moupinamide have strong binding with EGFR and MAPK1. Conclusion: The key active compounds of SMI in the treatment of COVID-19 may be Schisantherin A and Moupinamide, and the molecular mechanism may be related to key targets such as EGFR and MAPK1, and may be involved in the PI3K-Akt signaling pathway and MAPK signaling pathway.

6.
Bioprocess Biosyst Eng ; 44(10): 2051-2059, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33993384

RESUMO

The partial denitrification (PD) is a very promising process developed in the last decade, to study the comprehensive influence of influent carbon to nitrogen (C/N) on the activated sludge system under PD, six sequencing batch reactors (SBRs) were operated in parallel at C/N of 2.75, 3.30, 4.13, 5.50, 8.25 and 16.50, the nitrogen removal, phosphorus removal and sludge settleability of PD were investigated. The results showed that PD was observed treating synthetic wastewater in all the six SBRs, and the nitrite accumulation rate (NAR) was highest at C/N of 5.50 (NAR of 82.30%). However, due to the alternate inhibition of NO2--N and free nitrous acid (FNA) produced by a limited carbon source, both the sludge settleability and phosphorus removal deteriorated. The average SVI at C/N of 8.25 was 130% lower than C/N of 3.30, and the average amount of PO43--P released at C/N of 16.5 was 189% higher than C/N of 2.75. Kinetic analysis showed that the denitrification kinetics of PD and complete denitrification were similar, and the nitrite accumulation was caused by the difference between nitrate reduction rate and nitrite reduction rate. Variations of on-line parameters (pH and ORP) revealed that nitrite accumulation could be indicated by judging the nitrate turning point and nitrite turning point on pH and ORP curves, which provided guidance for the setup of PD.


Assuntos
Desnitrificação , Nitratos/análise , Nutrientes/isolamento & purificação , Reatores Biológicos , Concentração de Íons de Hidrogênio , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Esgotos , Águas Residuárias/química
7.
Adv Mater ; 32(31): e2002717, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32584475

RESUMO

Perovskites have been intensively investigated for their use in solar cells and light-emitting diodes. However, research on their applications in thin-film transistors (TFTs) has drawn less attention despite their high intrinsic charge carrier mobility. In this study, the universal approaches for high-performance and reliable p-channel lead-free phenethylammonium tin iodide TFTs are reported. These include self-passivation for grain boundary by excess phenethylammonium iodide, grain crystallization control by adduct, and iodide vacancy passivation through oxygen treatment. It is found that the grain boundary passivation can increase TFT reproducibility and reliability, and the grain size enlargement can hike the TFT performance, thus, enabling the first perovskite-based complementary inverter demonstration with n-channel indium gallium zinc oxide TFTs. The inverter exhibits a high gain over 30 with an excellent noise margin. This work aims to provide widely applicable and repeatable methods to make the gate more open for intensive efforts toward high-performance printed perovskite TFTs.

8.
Plant Sci ; 294: 110432, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32234227

RESUMO

Cold stress is one of the major environmental factors that limit growth and utilization of bermudagrass [Cynodon dactylon (L.) Pers], a prominent warm-season turfgrass. However, the molecular mechanism of cold response in bermudagrass remains largely unknown. In this study, we characterized a cold-responsive ERF (ethylene responsive factor) transcription factor, CdERF1, from bermudagrass. CdERF1 expression was induced by cold, drought and salinity stresses. The CdERF1 protein was nucleus-localized and encompassed transcriptional activation activity. Transgenic Arabidopsis plants overexpressing CdERF1 showed enhanced cold tolerance, whereas CdERF1-underexpressing bermudagrass plants via virus induced gene silencing (VIGS) method exhibited reduced cold resistance compared with control, respectively. Under cold stress, electrolyte leakage (EL), malondialdehyde (MDA), H2O2 and O2- contents were reduced, while the activities of SOD and POD were elevated in transgenic Arabidopsis. By contrast, these above physiological indicators in CdERF1-underexpressing bermudagrass exhibited the opposite trend. To further explore the possible molecular mechanism of bermudagrass cold stress response, the RNA-Seq analyses were performed. The result indicated that overexpression of CdERF1 activated a subset of stress-related genes in transgenic Arabidopsis, such as CBF2, pEARLI1 (lipid transfer protein), PER71 (peroxidase) and LTP (lipid transfer protein). Interestingly, under-expression of CdERF1 suppressed the transcription of many genes in CdERF1-underexpressing bermudagrass, also including pEARLI1 (lipid transfer protein) and PER70 (peroxidase). All these results revealed that CdERF1 positively regulates plant cold response probably by activating stress-related genes, PODs, CBF2 and LTPs. This study also suggests that CdERF1 may be an ideal candidate in the effort to improve cold tolerance of bermudagrass in the further molecular breeding.


Assuntos
Proteínas de Transporte/metabolismo , Cynodon/metabolismo , Proteínas de Plantas/metabolismo , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/genética , Resposta ao Choque Frio/genética , Resposta ao Choque Frio/fisiologia , Cynodon/genética , Inativação Gênica/fisiologia , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo
9.
ACS Appl Mater Interfaces ; 11(36): 33157-33164, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31431012

RESUMO

An optimized polyol reduction method was proposed for p-type CuxO deposition using a spin-coating method at low temperatures. The film characterizations and the electrical properties of integrated thin-film transistors (TFTs) were investigated as a function of annealing temperature and polyol type. The CuxO TFTs derived from propylene glycol showed the optimal performance with an average field-effect hole mobility of 0.15 cm2 V-1 s-1, an on/off current ratio of ∼104, and a threshold voltage of -7 V at a low temperature of 220 °C. Considering few investigations on the operational/air stability of solution-processed p-type oxide TFTs, we carried out systematical studies and revealed different roles of O2 and H2O on the device performance. The low activation energy (0.16 eV) for hole transport and high voltage gain (37) of the composed complementary inverter highlight great potential for the construction of all oxide-based transparent flexible electronics and circuits.

10.
Adv Mater ; : e1802379, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29974529

RESUMO

Here, room-temperature solution-processed inorganic p-type copper iodide (CuI) thin-film transistors (TFTs) are reported for the first time. The spin-coated 5 nm thick CuI film has average hole mobility (µFE ) of 0.44 cm2 V-1 s-1 and on/off current ratio of 5 × 102 . Furthermore, µFE increases to 1.93 cm2 V-1 s-1 and operating voltage significantly reduces from 60 to 5 V by using a high permittivity ZrO2 dielectric layer replacing traditional SiO2 . Transparent complementary inverters composed of p-type CuI and n-type indium gallium zinc oxide TFTs are demonstrated with clear inverting characteristics and voltage gain over 4. These outcomes provide effective approaches for solution-processed inorganic p-type semiconductor inks and related electronics.

11.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(9): 975-978, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-28899466

RESUMO

OBJECTIVE: To investigate the clinical and genetic features of two families with late-onset glutaric aciduria type II caused by ETFDH mutations. METHODS: Target gene sequence capture and next generation sequencing were used for sequencing of suspected patients and their family members. The patients' clinical features were retrospectively analyzed and literature review was performed. RESULTS: The probands of the two families had a clinical onset at the ages of 10 years and 5.5 years respectively, with the clinical manifestations of muscle weakness and muscle pain. Laboratory examinations revealed significant increases in the serum levels of creatine kinase, creatine kinase-MB, and lactate dehydrogenase. Tandem mass spectrometry showed increases in various types of acylcarnitines. The analysis of urine organic acids showed an increase in glutaric acid. Electromyography showed myogenic damage in both patients. Gene detection showed two novel mutations in the ETFDH gene (c.1331T>C from the mother and c.824C>T from the father) in patient 1, and the patient's younger brother carried the c.1331T>C mutation but had a normal phenotype. In patient 2, there was a novel mutation (c.177insT from the father) and a known mutation (c.1474T>C from the mother) in the ETFDH gene. Several family members carried such mutations. Both patients were diagnosed with glutaric aciduria type II. Their symptoms were improved after high-dose vitamin B2 treatment. CONCLUSIONS: For patients with unexplained muscle weakness and pain, serum creatine kinase, acylcarnitines, and urinary organic acids should be measured, and the possibility of glutaric aciduria type II should be considered. Genetic detection is helpful to make a confirmed diagnosis.


Assuntos
Flavoproteínas Transferidoras de Elétrons/genética , Proteínas Ferro-Enxofre/genética , Deficiência Múltipla de Acil Coenzima A Desidrogenase/genética , Mutação , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Criança , Biologia Computacional , Feminino , Humanos , Masculino , Deficiência Múltipla de Acil Coenzima A Desidrogenase/tratamento farmacológico
12.
Ecotoxicology ; 25(8): 1445-1457, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27443677

RESUMO

There is widespread distribution of salinized lands in northern China. Harnessing such land is essential to environmental health. Bermudagrass [Cynodon dactylon (L.) Pers.] has the potential to improve the salinized lands. However, low temperature remarkably limits the growth of bermudagrass in winter. Currently, there is no information about the interaction of cold and salt in this plant. Hence, the objectives of this study were to figure out the effects of combined cold and salinity stress on bermudagrass. In this study, 4 °C and 200 mM salt solution was used as cold and salt treatments respectively while 4 °C along with 200 mM salt solution were applied as combined stress. After 5 days treatment, bermudagrass displayed a dramatic decline in the turf quality and chlorophyll content, but higher malonaldehyde, electrolyte leakage, hydrogen peroxide content, antioxidant enzyme activity in the combined stress regime as compared to cold or salt treated alone. Analysis of chlorophyll a revealed that the combined stress aggravated stress-induced inhibition of photosystem II. In addition, the expressions of stress-related genes were up-regulated with a lower expression level when cold and salt applied together. In summary, the grass exposed to combined stress presented a relatively lower stress tolerance and suffered a more severe damage than grass grown in the other regimes. These findings are crucial for elucidating the molecular mechanisms of cold and salt combined stress in bermudagrass, and provide information for breeding programs to select and develop bermudagrass cultivars that are suitable for improvement of the northern China salinized land.


Assuntos
Temperatura Baixa , Cynodon/fisiologia , Fotossíntese/fisiologia , Estresse Fisiológico , China , Clorofila/metabolismo , Clorofila A , Complexo de Proteína do Fotossistema II/fisiologia , Tolerância ao Sal , Cloreto de Sódio
13.
Plant Physiol Biochem ; 100: 94-104, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26807934

RESUMO

Melatonin (N-acetyl-5-methoxytryptamine) has been reported to participate in plant development and abiotic stress responses. The main objective of this study was to investigate the role of melatonin in the cold-sensitive (S) and the cold-tolerant (T) bermudagrass genotypes' response to cold stress. The genotypes were treated with 100 µM melatonin and exposed to 4 °C temperature for 3 days. In both genotypes, cold stress increased the endogenous melatonin levels, and more prominently in T than S. Physiological responses indicated that exogenous melatonin triggered antioxidant activities in both genotypes, while it alleviated cell damage in the T genotype response to cold stress. Melatonin treatment under cold stress increased fluorescence curve levels for both genotypes, and higher in T than S genotypes. In both genotypes, the alterations in photosynthetic fluorescence parameters after melatonin treatment highlighted the participation of melatonin in improving photosystem response to cold stress, particularly for the cold-tolerant genotype. The metabolic analyses revealed the alterations of 44 cold-responsive metabolites in the two genotypes, mainly including carbohydrates, organic acids and amino acids. After exogenous melatonin treatment under cold condition, there was high accumulation of metabolites in the cold-tolerant regimes than their cold-sensitive counterparts. Collectively, the present study revealed differential modulations of melatonin between the cold-sensitive and the cold-tolerant genotypes in response to cold stress. This was mainly by impacting antioxidant system, photosystem II, as well as metabolic homeostasis.


Assuntos
Resposta ao Choque Frio/efeitos dos fármacos , Cynodon/metabolismo , Genótipo , Melatonina/farmacologia , Fotossíntese/efeitos dos fármacos , Resposta ao Choque Frio/genética , Cynodon/genética , Fotossíntese/genética
14.
Chemotherapy ; 60(5-6): 379-83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26496663

RESUMO

BACKGROUND: Quorum sensing (QS), as the basis of bacterial cell-to-cell communication, is a promising approach to reduce the incidence of multidrug resistance. The objective of this study was to search for novel quorum sensing inhibitors from plants and control detrimental infections. METHODS: The crude extracts of Ficus carica and Perilla frutescens were examined for their anti-QS properties. Powdered plant samples were treated sequentially with organic solvents of increasing polarity. The extracts of each solvent were concentrated in vacuo to give crude extracts and tested against Chromobacterium violaceum CV026 and Pseudomonas aeruginosa PA01 especially. Anti-QS activity was measured by quantifying violacein production and swarming motility. RESULTS: All extracts of these two plants display anti-QS ability. Interestingly, the extract of F. carica with dichloromethane and of P. frutescens with MeOH exhibited the most pronounced inhibition of QS activity. CONCLUSIONS: These two plants can offer bioactive natural products with potential for attenuating pathogens.


Assuntos
Antibacterianos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Ficus , Perilla frutescens , Percepção de Quorum/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Chromobacterium/efeitos dos fármacos , Chromobacterium/fisiologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Humanos , Folhas de Planta , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum/fisiologia
15.
Bioresour Technol ; 134: 87-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23500564

RESUMO

The optimization, purification and characterization of bioflocculant produced by Paenibacillus elgii B69 were investigated. The bioflocculant was an exopolysaccharide composed of glucose, glucuronic acid, mannose and xylose. The maximum bioflocculant production was about 25.63 g/L achieved with sucrose at 51.35 g/L, peptone at 6.78 g/L and yeast extract at 0.47 g/L optimized by response-surface methodology. In addition, a series of experiments was performed to investigate the flocculation activities towards kaolin clay, dyeing pigment, heavy metal ion, and real wastewater and the result indicated the new bioflocculant had high activities towards all the tested pollutions. These results showed its great potential for water pretreatment used in industry.


Assuntos
Paenibacillus/metabolismo , Polissacarídeos/química , Águas Residuárias/microbiologia , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental/efeitos dos fármacos , Carbono/farmacologia , Cor , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Floculação , Íons , Metais Pesados/isolamento & purificação , Nitrogênio/farmacologia , Paenibacillus/efeitos dos fármacos , Reprodutibilidade dos Testes , Poluentes Químicos da Água/isolamento & purificação
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