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1.
Adv Mater ; : e2205338, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36189887

RESUMO

The generation of photoinduced defects and freely moving halogen ions is dynamically updated in real time. Accordingly, most reported strategies are static and short-term, which make their improvements in photostability very limited. Therefore, seeking new passivation strategies to match the dynamic characteristics of defect generation is very urgent. Without newly generated defects, a passivation molecule should exist in the configuration that would not become the initiation sites for defect generation. With newly generated defects, the passivation molecule should transfer into the other configuration that possesses the passivation sites. Herein, a classical photoisomeric molecule, spiropyran, is adopted, whose pre- and post-isomeric forms meet the requirements for two different configurations, to realize the state transition once the photoinduced defects appear during subsequent operation and dynamic capture for continuous renewal of defects. Consequently, spiropyrans work as light-triggered and self-healing sustainable passivation sites to realize continuous defect repair. The target devices retain 93% and 99% of their initial power conversion efficiencies after 456 h aging under ultraviolet illumination and 1200 h aging under full-spectrum illumination, respectively. This work provides a novel concept of sustainable passivation strategy to realize continuous defect-passivation and film-healing in perovskite photovoltaics.

2.
Environ Sci Technol ; 56(22): 15685-15694, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36251006

RESUMO

Aquatic environments are important reservoirs of antibiotic wastes, antibiotic resistance genes, and bacteria, enabling the persistence and proliferation of antibiotic resistance in different bacterial populations. To prevent the spread of antibiotic resistance, effective approaches to detect antimicrobial susceptibility in aquatic environments are highly desired. In this work, we adopt a metabolism-based bioorthogonal noncanonical amino acid tagging (BONCAT) method to detect, visualize, and quantify active antimicrobial-resistant bacteria in water samples by exploiting the differences in bacterial metabolic responses to antibiotics. The BONCAT approach can be applied to rapidly detect bacterial resistance to multiple antibiotics within 20 min of incubation, regardless of whether they act on proteins or DNA. In addition, the combination of BONCAT with the microscope enables the intuitive characterization of antibiotic-resistant bacteria in mixed systems at single-cell resolution. Furthermore, BONCAT coupled with flow cytometry exhibits good performance in determining bacterial resistance ratios to chloramphenicol and population heterogeneity in hospital wastewater samples. In addition, this approach is also effective in detecting antibiotic-resistant bacteria in natural water samples. Therefore, such a simple, fast, and efficient BONCAT-based approach will be valuable in monitoring the increase and spread of antibiotic resistance within natural and engineered aquatic environments.


Assuntos
Aminoácidos , Bactérias , Bactérias/genética , Antibacterianos/farmacologia , Água
3.
J Am Chem Soc ; 144(40): 18470-18478, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36164747

RESUMO

Despite recent encouraging developments, achieving efficient blue perovskite light-emitting diodes (PeLEDs) have been widely considered a critical challenge. The efficiency breakthrough only occurred in the sky-blue region, and the device performance of pure-blue and deep-blue PeLEDs lags far behind those of their sky-blue counterparts. To avoid the negative effects associated with dimensionality reduction and excess chloride typically needed to achieve deep-blue emission, here we demonstrate guanidine (GA+)-induced deep-blue (∼457 nm) perovskite emitters enabling spectrally stable PeLEDs with a record external quantum efficiency (EQE) over 3.41% through a combination of quasi-2D perovskites and halide engineering. Owing to the presence of GA+, even a small inclusion of chloride ions is sufficient for generating deep-blue electroluminescence (EL), in clear contrast to the previously reported deep-blue PeLEDs with significant chloride inclusion that negatively affects spectral stability. Based on the carrier dynamics analysis and theoretical calculation, GA+ is found to stabilize the low-dimensional species during annealing, retarding the cascade energy transfer and facilitating the deep-blue EL. Our findings open a potential third route to achieve deep-blue PeLEDs beyond the conventional methods of dimensionality reduction and excessive chloride incorporation.

4.
Small ; 18(28): e2201930, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35723194

RESUMO

Defect states play an important role in the photovoltaic performance of metal halide perovskites. Particularly, the passivation of surface defects has made great contributions to high-performance perovskite photovoltaics. This highlights the importance of understanding the surface defects from a fundamental level by developing more accurate and operando characterization techniques. Herein, a strategy to enable the surface carriers and photocurrent distributions on perovskite films to be visualized in the horizontal direction is put forward. The visual image of photocurrent distribution is realized by combining the static local distribution of carriers provided by scanning near-field optical microscopy with the dynamic transporting of carriers achieved via a scanning photocurrent measurement system. Taking a surface passivated molecule as an example, a comprehensive defect scene including static and dynamic as well as local and entire conditions is obtained using this strategy. The comprehensive analysis of the trap states in perovskite films is pioneered vertically and horizontally, which will powerfully promote the deep understanding of defect mechanisms and carrier behavior for the goal of fabricating high-performance perovskite optoelectronic devices.

5.
J Tradit Chin Med ; 42(1): 23-29, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35294119

RESUMO

OBJECTIVE: To investigate the protective efficacy of Bushen Culuan decoction (BCD) on ovarian follicle and follicular granulosa cells in mice with premature ovarian insufficiency (POI) induced by tripterygium wilfordii polyglycoside, and to study the potential mechanism underlying the action. METHODS: Eighty female Balb/c mice were randomly divided into 4 groups (n = 20 each): blank group, model group, Bushen Culuan decoction intervening group (BCD group) and estradiol valerate intervening group (EV group). In the first 14 model establishing d, mice in model group, BCD group and EV group were under Tripterygium wilfordii polyglycoside (TWP) gavage to establish POI models. In the 14-day therapeutic stage, mice in BCD group were taken BCD 18.35 mg·kg-1d-1, mice in EV group were taken EV solution 0.15 mg·kg-1d-1, while mice in blank group and model group were taken normal saline. When the mice accomplished therapy, whole blood was collected for serum hormone including follicle stimulating hormone (FSH), luteal hormone (LH), estradiol (E2), antimullerian hormone (AMH) levels and vascular endothelial growth factor (VEGF), bone morphogenetic protein-7 (BMP-7) measurement. Ovarian tissues were harvested for morphologic observation, follicle counting, ovarian follicular graulosa cell apoptosis test and testing BMP-7 and caspase-3 expressions. RESULTS: The body weights of the mice kept growing stably in the process expect in TWP intervening stage. Compared with model group, BCD group had significantly higher ovarian index, serum E2, AMH, VEGF, BMP-7 levels and significantly lower FSH level (P < 0.05). Meanwhile the VEGF level in BCD group was higher than in EV group (P < 0.05). Compared with model group, the histopathological damage and GCs apoptosis were mitigated; developing follicle counting, BMP-7 expression were up-regulated, and caspase-3 expression was downregulated in BCD groups (P < 0.05). CONCLUSION: BCD treatment could attenuate pathological process in POI ovaries, suppress GC apoptosis, probably through promoting BMP-7 expression and following inhibiting caspase-3 activation.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Ovariana Primária , Animais , Proteína Morfogenética Óssea 7 , Caspase 3/genética , Medicamentos de Ervas Chinesas/uso terapêutico , Estradiol , Feminino , Hormônio Foliculoestimulante , Células da Granulosa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Folículo Ovariano , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/tratamento farmacológico , Insuficiência Ovariana Primária/genética , Tripterygium/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/genética
6.
Adv Mater ; 34(16): e2200320, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35201633

RESUMO

Perovskite photovoltaics are strong potential candidates to drive low-power off-grid electronics for indoor applications. Compared with rigid devices, flexible perovskite devices can provide a more suitable surface for indoor small electronic devices, enabling them have a broader indoor application prospect. However, the mechanical stability of flexible perovskite photovoltaics is an urgent issue solved. Herein, a kind of 3D crosslinking agent named borax is selected to carry out grain boundary penetration treatment on perovskite film to realize full-dimensional stress release. This strategy improves the mechanical and phase stabilities of perovskite films subjected to external forces or large temperature changes. The fabricated perovskite photovoltaics deliver a champion power conversion efficiency (PCE) of 21.63% under AM 1.5G illumination, which is the highest one to date. The merit of low trap states under weak light makes the devices present a superior indoor PCE of 31.85% under 1062 lux (LED, 2956 K), which is currently the best flexible perovskite indoor photovoltaic device. This work provides a full-dimensional grain boundary stress release strategy for highly stable flexible perovskite indoor photovoltaics.

7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(6): 1864-1868, 2021 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-34893124

RESUMO

OBJECTIVE: To investigate the characteristics of gene mutations in patients with myelodysplastic syndromes (MDS) and its prognostic significance. METHODS: High-throughput sequencing was used to detect 34 blood tumor-related genes in 210 patients with MDS, and the relationship with the revised International Prognostic Scoring System (IPSS-R) and the impact on prognosis of the patients were analyzed. RESULTS: Among the 210 MDS patients, 142 cases (67.6%) showed mutations, and the first six genes with the highest mutation detection rate were ASXL1(20.5%), TET2(17.1%), U2AF1(14.3%), DNMT3A (11.9%), TP53(10.5%) and RUNX1(10.0%). The gene mutation rate of the patients in IPSS-R relatively high-risk group was higher than those in relatively low-risk group (P=0.001). Both TP53 and BCOR genes showed higher mutation rates in the higher risk group than in the lower risk group (P<0.05). Survival time of the patients in TP53 mutant group was lower than those in non-mutant group (P<0.001), survival time of patients in SF3B1 mutant group was higher than those in non-mutant group (P=0.018). According to the number of gene mutations, the patients could be divided into groups with 0-1, 2 and ≥3 gene mutations, and the median OS of the three groups were not reached, 43 and 27 months, respectively (P=0.004). The Multivariate analysis showed that the increasing number of gene mutations and TP53 mutation was the independent risk factors affecting prognosis of the patients, while SF3B1 mutation was the independent protective factor for the prognosis of the patients. CONCLUSION: The gene mutation rate was higher in MDS patients. And the increasing numbers of gene mutation, TP53 and SF3B1 were the influence factors of prognosis in the patients.


Assuntos
Síndromes Mielodisplásicas , Genes Reguladores , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Síndromes Mielodisplásicas/genética , Prognóstico
8.
Chem Sci ; 12(36): 11936-11954, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34667561

RESUMO

With the rapid development of the Internet of Things (IoTs), photovoltaics (PVs) has a vast market supply gap of billion dollars. Moreover, it also puts forward new requirements for the development of indoor photovoltaic devices (IPVs). In recent years, PVs represented by organic photovoltaic cells (OPVs), silicon solar cells, dye-sensitized solar cells (DSSCs), etc. considered for use in IoTs mechanisms have also been extensively investigated. However, there are few reports on the indoor applications of perovskite devices, even though it has the advantages of better performance. In fact, perovskite has the advantages of better bandgap adjustability, lower cost, and easier preparation of large-area on flexible substrates, compared with other types of IPVs. This review starts from the development status of IoTs and investigates the cost, technology, and future trends of IPVs. We believe that perovskite photovoltaics is more suitable for indoor applications and review some strategies for fabricating high-performance perovskite indoor photovoltaic devices (IPVs). Finally, we also put forward a perspective for the long-term development of perovskite IPVs.

9.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2644-2649, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34296560

RESUMO

To study the clinical efficacy and safety of Bushen Huoxue Culuan Formula in treating infertility caused by diminished ovarian reserve(DOR) with kidney deficiency and blood stasis. A total of 100 DOR patients treated at Xiyuan Hospital, Acupuncture Hospital and Clinic of China Academy of Chinese Medical Sciences from 2017 to 2020 in line with the inclusion criteria were selected and randomly divided into experimental group and control group at the ratio of 1∶1. The experimental group was treated with Bushen Huoxue Culuan Formular, while the control group was treated with Climen and Clomiphene for 3 menstrual cycles. The ovulation rate, pregnancy rate, pregnancy success rate, serum hormone levels, and traditional Chinese medicine(TCM) symptom scores were observed in the 2 groups. The total effective rate was 92.00% in the experimental group and 72.00% in the control group, with a statistical difference between the two groups(P<0.01); the experimental group was superior to the control group in reducing FSH level, increasing AMH level, improving TCM symptoms, increasing pregnancy rate and pregnancy success rate, with a significant difference(P<0.05). There was no abnormal safety indicator and adverse reaction. Bushen Huoxue Culuan Formular is effective in treating infertility caused by DOR due to kidney deficiency and blood stasis, with a safety and reliability.


Assuntos
Medicamentos de Ervas Chinesas , Infertilidade Feminina , Reserva Ovariana , China , Feminino , Humanos , Infertilidade Feminina/tratamento farmacológico , Rim , Gravidez , Reprodutibilidade dos Testes , Resultado do Tratamento
10.
New Phytol ; 231(6): 2215-2230, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34101835

RESUMO

Moso bamboo (Phyllostachys edulis) is a fast-growing species with uneven growth and lignification from lower to upper segments within one internode. MicroRNAs (miRNAs) play a vital role in post-transcriptional regulation in plants. However, how miRNAs regulate fast growth in bamboo internodes is poorly understood. In this study, one moso bamboo internode was divided during early rapid growth into four segments called F4 (bottom) to F1 (upper) and these were then analysed for transcriptomes, miRNAs and degradomes. The F4 segment had a higher number of actively dividing cells as well as a higher content of auxin (IAA), cytokinin (CK) and gibberellin (GA) compared with the F1 segment. RNA-seq analysis showed DNA replication and cell division-associated genes highly expressed in F4 rather than in F1. In total, 63 miRNAs (DEMs) were identified as differentially expressed between F4 and F1. The degradome and the transcriptome indicated that many downstream transcription factors and hormonal responses genes were modulated by DEMs. Several miR-target interactions were further validated by tobacco co-infiltration. Our findings give new insights into miRNA-mediated regulatory pathways in bamboo, and will contribute to a comprehensive understanding of the molecular mechanisms governing rapid growth.


Assuntos
MicroRNAs , Regulação da Expressão Gênica de Plantas , Giberelinas , Ácidos Indolacéticos , MicroRNAs/genética , Poaceae/genética , Transcriptoma/genética
11.
Cell Tissue Res ; 384(2): 231-240, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33544212

RESUMO

Cardiovascular diseases are the leading cause of death in the world due to the high incidence of the diseases coupled with the limited therapeutic options. In recent years, advances in regenerative medicine have emerged as a promising treatment. Differentiation of induced pluripotent stem cells (iPSCs) into cardiac cells and emerging technologies allowing arrangement of cells into complex 3D tissue-like structures open new frontiers for transplantation and engraftment of these tissue patches onto the damaged heart. Despite the cells integrating and presenting initial neovascularization, the functional and electric properties of these patches are still not comparable with those of the host cardiac tissue. Future research optimizing maturation and integration of the iPSC-derived cardiomyocytes is paramount for cardiac cell therapy to attain clinical use. Herein, we will review the state of the art and the different approaches to constructing these 3D transplantable structures.


Assuntos
Regeneração Tecidual Guiada/métodos , Imageamento Tridimensional/métodos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Engenharia Tecidual/métodos , Diferenciação Celular , Humanos , Miócitos Cardíacos/citologia
12.
J Am Chem Soc ; 143(6): 2593-2600, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33535753

RESUMO

The inorganic lead-free Cs2AgBiBr6 double perovskite structure is the promising development direction in perovskite solar cells (PSCs) to solve the problem of the instability of the APbX3 structure and lead toxicity. However, the low short-circuit current and power conversion efficiency (PCE) caused by the low crystallization of Cs2AgBiBr6 greatly limit the optoelectronic application. Herein, we adopt a simple strategy to dope single-layered MXene nanosheets into titania (Ti3C2Tx@TiO2) as a multifunctional electron transport layer for stable and efficient Cs2AgBiBr6 double PSCs. The single-layered MXene nanosheets significantly improve the electrical conductivity and electron extraction rate of TiO2; meanwhile, the single-layered MXene nanosheets change the surface wettability of the electron transport layer and promote the crystallization of the Cs2AgBiBr6 double perovskite in solar cell devices. Therefore, the PCE went up by more than 40% to 2.81% compared to that of a TiO2 based device, and the hysteresis was greatly suppressed. Furthermore, the device based on Ti3C2Tx@TiO2 showed the long-term operating stability. After storing the device for 15 days under ambient air conditions, the PCE still remained a retention rate of 93% of the initial one. Our finding demonstrates the potential of Ti3C2Tx@TiO2 in electron transfer material of high-performance double PSCs.

13.
Science ; 371(6529): 636-640, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33542138

RESUMO

The band edges of metal-halide perovskites with a general chemical structure of ABX3 (A, usually a monovalent organic cation; B, a divalent cation; and X, a halide anion) are constructed mainly of the orbitals from B and X sites. Hence, the structural and compositional varieties of the inorganic B-X framework are primarily responsible for regulating their electronic properties, whereas A-site cations are thought to only help stabilize the lattice and not to directly contribute to near-edge states. We report a π-conjugation-induced extension of electronic states of A-site cations that affects perovskite frontier orbitals. The π-conjugated pyrene-containing A-site cations electronically contribute to the surface band edges and influence the carrier dynamics, with a properly tailored intercalation distance between layers of the inorganic framework. The ethylammonium pyrene increased hole mobilities, improved power conversion efficiencies relative to that of a reference perovskite, and enhanced device stability.

14.
Food Chem ; 339: 127885, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32866704

RESUMO

The current study develops an effective, convenient, low-cost, and environmentally friendly method for determining trans-resveratrol (TRA) in peanut oils, the unique proportion of peanut oil, by employing natural cotton fibers without any pretreatment as extraction sorbent and an in-syringe extraction device. The primary factors affecting the extraction recovery are optimized in detail. The condition of 200.0 mg of cotton fibers, six push-pull times, 2.0 mL of n-hexane as washing solvent and 2.0 mL of ethanol as desorption solvent is selected as the best. The linear range is demonstrated to be 10-1000 ng/g with a satisfactory correlation coefficient (R2 = 0.9995), while the limit of detection is calculated as 2.47 ng/g. In addition, the recoveries of TRA are obtained in the range of 93.8-104.4% with RSDs less than 5.5%. Finally, the developed method is successfully applied to determine TRA concentrations in commercial peanut oils and other edible oils.


Assuntos
Arachis/química , Cromatografia Líquida de Alta Pressão/métodos , Fibra de Algodão , Óleo de Amendoim/química , Resveratrol/análise , Adsorção , Arachis/metabolismo , Hexanos/química , Isomerismo , Limite de Detecção , Reprodutibilidade dos Testes , Resveratrol/isolamento & purificação , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Espectrofotometria Ultravioleta
15.
Front Bioeng Biotechnol ; 9: 811917, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35223819

RESUMO

Metabolic disorders are major clinical challenges of health that are progressing globally. A concurrence of metabolic disorders such as obesity, insulin resistance, atherogenic dyslipidemia, and systematic hypertension leads to metabolic syndrome. Over the past years, the metabolic syndrome leads to a five- and two-fold rise in diabetes mellitus type II and cardiovascular diseases. Natural products specifically plant extracts have insulin-sensitizing, anti-inflammatory, and antioxidant properties and are also considered as an alternative option due to few adverse effects. Nanotechnology is one of the promising strategies, which improves the effectiveness of treatment and limits side effects. This review mainly focuses on plant extract-based nanosystems in the management of the metabolic syndrome. Numerous nano-drug delivery systems, i.e., liposomes, hydrogel nanocomposites, nanoemulsions, micelles, solid lipid, and core-shell nanoparticles, have been designed using plant extracts. It has been found that most of the nano-formulations successfully reduced oxidative stress, insulin resistance, chronic inflammation, and lipid profile in in vitro and in vivo studies as plant extracts interfere with the pathways of metabolic syndrome. Thus, these novel plant-based nanosystems could act as a promising candidate for clinical applications.

16.
Sci Bull (Beijing) ; 66(4): 347-353, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36654414

RESUMO

Over the years, the efficiency of inorganic perovskite solar cells (PSCs) has increased at an unprecedented pace. However, energy loss in the device has limited a further increase in efficiency and commercialization. In this work, we used (NH4)2C2O4·H2O to treat CsPbBrI2 perovskite film during spin-coating. The CsPbBrI2 underwent secondary crystallization to form high quality films with micrometer-scale and low trap density. (NH4)2C2O4·H2O treatment promoted charge transfer capacity and reduced the ideal factor. It also dropped the energy loss from 0.80 to 0.64 eV. The resulting device delivered a power conversion efficiency (PCE) of 16.55% with an open-circuit voltage (Voc) of 1.24 V, which are largely improved compared with the reference device which exhibited a PCE of 13.27% and a Voc of 1.10 V. In addition, the optimized treated device presented a record indoor PCE of 28.48% under a fluorescent lamp of 1000 lux, better than that of the reference device (19.05%).

17.
Ying Yong Sheng Tai Xue Bao ; 31(9): 2977-2984, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-33345498

RESUMO

Stellera chamaejasme is one of most common poisonous plant species in degraded grasslands of China. S. chamaejasme could dominate the community in some severely degraded grasslands, which is a serious threat to the sustainable development of animal husbandry in natural grasslands. In this study, S. chamaejasme population was divided into 10 age classes according to the number of branches. We investigated the age structure of S. chamaejasme population and population dynamic indices, and quantified the survival status of S. chamaejasme population by compiling a static life table, drawing a survival curve, conducting survival analysis. The age structure of S. chamaejasme population in the study area was growth type. The number of individuals in Ⅰ age class was sufficient but with relatively low survival rate. The population structure of S. chamaejasme was fitted the growing type. The development process of population was fluctuating. The number of individuals would drop sharply in Ⅱ and Ⅷ, indicating that these two age classes were the bottleneck period in the development of S. chamaejasme population. The survival curves of S. chamaejasme population was the Deevey-Ⅱ type. The results of survival analysis showed that the population had a sharp decrease in the early stage and was stable in the later stage, which was because the value of fx and λx of S. chamaejasme in Ⅰ or Ⅱ age class were the highest. In conclusion, sufficient young individuals (Ⅰ) was the basis for the expansion of S. chamaejasme population in the degraded typical steppe. The low transformation rate of young individuals to adults might be one of the reasons explaining why S. chamaejasme population could not expand rapidly in the early stage of grassland degradation. Therefore, it was suggested to intervene early when the number of S. chamaejasme was limited.


Assuntos
Thymelaeaceae , Animais , China , Humanos
18.
Sci Rep ; 10(1): 10306, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32587358

RESUMO

The effects of increasing yield and quality of virus-free chewing cane seedlings and their physiological and molecular basis were studied in this study. Results showed that compared with infected seedlings (the control), the yield of chewing cane stems grown from virus-free seedlings increased by 21.81-29.93%, stem length increased by 28.66-34.49 cm, internode length increased by 2.16-2.68 cm, the single stem weight increased by 20.10-27.68%, the reducing sugar increased by 0.91-1.15% (absolute value), and sucrose increased by - 0.06-1.33% (absolute value). The decrease in sucrose content did not reach significant level, but all other parameters were reached significant level. The chlorophyll content, photosynthetic parameters such as stomatal conductance (Gs), net photosynthetic rate (Pn) and transpiration rate (Tr), the activity of photosynthetic key enzymes ribulose-1,5-bisphosphate carboxylase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC), and gene (pepc, rbcS, and rbcL) expression levels were all greater in virus-free seedlings than infected seedlings. The content of superoxide anion (O2-) and malondialdehyde (MDA) in virus-free seedlings was lower than infected seedlings at the main growth stage. With increased development, the activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were gradually higher in virus-free seedlings than infected seedlings. Our results indicate that virus-free seedlings may improve photosynthesis efficiency and promote photosynthesis by increasing chlorophyll content, photosynthetic key enzyme activity, and the gene expression levels in leaves. By increasing the activity of antioxidant enzymes, reducing the degree of membrane lipid peroxidation, and improving the stress resistance of chewing cane, the virus-free chewing cane seedlings increased yield and quality. Our findings provide a scientific and theoretical basis for the promotion and application of virus-free chewing cane seedlings.


Assuntos
Saccharum/fisiologia , Plântula/crescimento & desenvolvimento , Clorofila/análise , Qualidade dos Alimentos , Interações Hospedeiro-Patógeno/fisiologia , Peroxidação de Lipídeos , Malondialdeído/análise , Lipídeos de Membrana/metabolismo , Vírus do Mosaico/patogenicidade , Fotossíntese , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Transpiração Vegetal , Saccharum/química , Saccharum/virologia , Plântula/química , Plântula/metabolismo , Plântula/virologia , Sacarose/análise , Superóxidos/análise
19.
ACS Appl Mater Interfaces ; 12(19): 21772-21778, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32319284

RESUMO

Organic-inorganic halide perovskite solar cells (PSCs) still suffer from stability issues which are caused by possible erosions from moisture, ultraviolet (UV) light, heat, and so forth. An electron-transporting layer (ETL), that is, TiO2, is a key component for state-of-the-art PSCs. However, UV-caused desorption of O2- in TiO2 would accelerate the degradation of PSCs. Herein, we explored perovskite oxide, NaTaO3, for the first time as an alternative ETL in PSCs. NaTaO3 as an ETL can effectively avoid the damage from UV irradiation, inhibit the degradation of the perovskite layer, and improve the overall stability of the PSC. PSCs fabricated with NaTaO3 yielded a power conversion efficiency (PCE) of 21.07% with a retention of more than 80% of this initial PCE after 240 min UV irradiation in air while the reference device with a PCE of 20.16% can only retain about 53% of its initial PCE after the same testing condition. The developed stable perovskite oxide material of NaTaO3 provides the diversification of electron-selective contact for highly efficient and stable PSCs.

20.
Biosens Bioelectron ; 156: 112136, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32174561

RESUMO

Shewanella oneidensis MR-1, a model species of exoelectrogenic bacteria (EEB), has been widely applied in bioelectrochemical systems. Biofilms of EEB grown on electrodes are essential in governing the current output and power density of bioelectrochemical systems. The MR-1 genome is exceptionally dynamic due to the existence of a large number of insertion sequence (IS) elements. However, to date, the impacts of IS elements on the biofilm-forming capacity of EEB and performance of bioelectrochemical systems remain unrevealed. Herein, we isolated a non-motile mutant (NMM) with biofilm-deficient phenotype from MR-1. We found that the insertion of an ISSod2 element into the flrA (encoding the master regulator for flagella synthesis and assembly) of MR-1 resulted in the non-motile and biofilm-deficient phenotypes in NMM cells. Notably, such a variant was readily confused with the wild-type strain because there were no obvious differences in growth rates and colonial morphologies between the two strains. However, the reduced biofilm formation on the electrodes and the deteriorated performances of bioelectrochemical systems and Cr(VI) immobilization for the strain NMM were observed. Given the wide distribution of IS elements in EEB, appropriate cultivation and preservation conditions should be adopted to reduce the likelihood that IS elements-mediated mutation occurs in EEB. These findings reveal the negative impacts of IS elements on the biofilm-forming capacity of EEB and performance of bioelectrochemical systems and suggest that great attention should be given to the actual physiological states of EEB before their applications.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Biofilmes/crescimento & desenvolvimento , Shewanella/fisiologia , Elementos de DNA Transponíveis , Eletricidade , Shewanella/genética , Shewanella/crescimento & desenvolvimento
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