Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 580
Filtrar
1.
Chemistry ; : e202401063, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654592

RESUMO

14,14'-Bidibenzo[a,j]anthracenes (BDBAs) were prepared by iridium-catalyzed annulation of 5,5'-biterphenylene with alkynes. Overcrowded BDBAs with highly distorted molecular halves and a small interplanar angle between two anthryl moieties (down to approximately 31º, currently the lowest reported value) were verified by X-ray crystallography. The strong intramolecular interactions and electronic couplingsbetween two molecular halves resulted in upfield 1H NMR signals, redshifted absorption and emission bands, and a reduced HOMO-LUMO gap. Photodynamic investigations on BDBAs indicated that the formation of the conventional symmetry-breaking charge transfer (SBCT) state was suspended by restricted rocking around the central C-C bond. Such a mechanism associated with this highly constrained conformation was examined for the first time.

2.
Inorg Chem ; 63(17): 7705-7713, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38620065

RESUMO

Herein, three In(III)-based metal-organic frameworks (In-MOFs) with different degrees of interpenetration (DOI), namely In-MOF-1, In-MOF-2, and In-MOF-3, constructed by In3+ and Y-shaped ligands 4,4',4″-s-triazine-2,4,6-triyltribenzoate (H3TATB), are successfully synthesized through the ionothermal/solvothermal method. Subsequently, three novel In-MOFs, including noninterpenetration polycatenation, 2-fold interpenetrated, and 4-fold interpenetrated structure, are employed as the platform for systematically investigating the separation efficiency of CO2/N2, CO2/CH4, and CO2/CH4/N2 mixture gas system. Among them, In-MOF-2 shows the highest CO2 uptake capacities at 298 K and simultaneously possesses the low adsorption enthalpy of CO2 (26.4 kJ/mol at low coverage), a feature desirable for low-energy-cost adsorbent regeneration. The CO2/N2 (v: v = 15/85) selectivity of In-MOF-2 reaches 37.6 (at 298 K and 1 bar), also revealing outstanding selective separation ability from flue gases and purifying natural gas, affording a unique robust separation material as it has moderate DOI and pore size. In-MOF-2 shows exceptional stability and feasibility to achieve reproducibility. Aperture adjustment makes In-MOF-2 a versatile platform for selectively capturing CO2 from flue gases or purifying natural gas.

3.
Huan Jing Ke Xue ; 45(5): 3016-3026, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629562

RESUMO

Sweet sorghum has a large biomass and strong cadmium (Cd) absorption capacity, which has the potential for phytoremediation of Cd-contaminated soil. In order to study the Cd phytoremediation effect of sweet sorghum assisted with citric acid on the typical parent materials in southern China, a field experiment was carried out in two typical parent material farmland areas (neutral purple mud field and jute sand mud field) with Cd pollution in Hunan Province. The results showed that:① Citric acid had no inhibitory effect on the growth of sweet sorghum. After the application of citric acid, the aboveground biomass of sweet sorghum at the maturity stage increased by 10.1%-24.7%. ② Both sweet sorghum planting and citric acid application reduced the soil pH value, and the application of citric acid further reduced the soil pH value at each growth stage of sweet sorghum; this decrease was greater in the neutral purple mud field, which decreased by 0.24-0.72 units. ③ Both sweet sorghum planting and citric acid application reduced the total amount of soil Cd, and the decreases in the neutral purple mud field and jute sand mud field were 23.8%-52.2% and 17.1%-31.8%, respectively. The acid-extractable percentage of soil Cd in both places increased by 38.6%-147.7% and 4.8%-22.7%, respectively. ④ The application of citric acid could significantly increase the Cd content in various tissues of sweet sorghum. The Cd content in the aboveground part of the plant in the neutral purple mud field was higher than that in the jute sand mud field, and the Cd content in stems and leaves was 0.25-1.90 mg·kg-1 and 0.21-0.64 mg·kg-1, respectively. ⑤ After applying citric acid, the Cd extraction amount of sweet sorghum in neutral purple mud soil in the mature stage reached 47.56 g·hm-2. In summary, citric acid could enhance the efficiency of sweet sorghum in the phytoremediation of Cd-contaminated soil, and the effect was better in neutral purple mud fields. This technology has the potential for remediation coupled with agro-production for heavy metal-contaminated farmland.


Assuntos
Poluentes do Solo , Sorghum , Cádmio/análise , Biodegradação Ambiental , Solo , Areia , Ácido Cítrico , Poluentes do Solo/análise , China , Grão Comestível/química
4.
Huan Jing Ke Xue ; 45(5): 2757-2766, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629539

RESUMO

Hutuo River Basin straddles Shanxi and Hebei provinces, and Hutuo River was once cut off due to economic development and urban expansion after 2000; however, with the national emphasis on ecological civilization and the implementation of the South-North Water Diversion Project, the ecological protection of Hutuo River Basin has been significantly improved. MODIS data, Landsat data, and night light remote sensing data were selected based on the google earth engine (GEE) platform, and a new evaluation index system was generated by combining the biological richness index, vegetation cover index, land stress index, and pollution load index in the ecological environment index (EI) and the humidity index in the remote sensing ecological index (RSEI), using the variation coefficient method and entropy weighting method to assign weights to these indices. An ecological environment evaluation model was constructed to evaluate and classify the ecological environment quality of Hutuo River Basin from 2000 to 2020, and the driving factors were interpreted by using geographic probes. The results showed that:① on a time scale, the ecological environment of Hutuo River Basin was in a decline period from 2000 to 2015 and a recovery period from 2015 to 2020. From a grid scale, the ecological environment quality in the central part of the basin showed a state of improvement year by year, and in the western and eastern parts of the basin, the ecological environment quality in the decline period decreased year by year, whereas the ecological environment quality in the recovery period improved. ② Hot spot analysis showed that the spatial distribution of the ecological environment quality in Hutuo River Basin was high in the middle and low on both sides. Cold spot regions were mainly located in major cities and towns in the eastern and southern parts and scattered in the river valley area on the west side. ③ Geodetection analysis showed that the single factor detection drivers were mainly population density, vegetation net primary productivity (NPP), fractional vegetation cover (FVC), and geomorphological type. The dominant factor of cross-detection was "geomorphological type + FVC." With the deepening of ecological civilization construction and the implementation of Hutuo River Protection Regulations, in combination with different factors such as the natural environment and social characteristics in this basin, the research on ecological environment evaluation in Hutuo River Basin can provide data support for proposing localized policies to improve the ecological environment.

5.
Anal Chem ; 96(17): 6847-6852, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38639290

RESUMO

Organic photoelectrochemical transistor (OPECT) has shown substantial potential in the development of next-generation bioanalysis yet is limited by the either-or situation between the photoelectrode types and the channel types. Inspired by the dual-photoelectrode systems, we propose a new architecture of dual-engine OPECT for enhanced signal modulation and its biosensing application. Exemplified by incorporating the CdS/Bi2S3 photoanode and Cu2O photocathode within the gate-source circuit of Ag/AgCl-gated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) channel, the device shows enhanced modulation capability and larger transconductance (gm) against the single-photoelectrode ones. Moreover, the light irritation upon the device effectively shifts the peak value of gm to zero gate voltage without degradation and generates larger current steps that are advantageous for the sensitive bioanalysis. Based on the as-developed dual-photoelectrode OPECT, target-mediated recycling and etching reactions are designed upon the CdS/Bi2S3, which could result in dual signal amplification and realize the sensitive microRNA-155 biodetection with a linear range from 1 fM to 100 pM and a lower detection limit of 0.12 fM.


Assuntos
Cobre , Técnicas Eletroquímicas , Sulfetos , Tiofenos , Técnicas Eletroquímicas/instrumentação , Cobre/química , Sulfetos/química , Compostos de Cádmio/química , Técnicas Biossensoriais/instrumentação , Bismuto/química , Transistores Eletrônicos , Processos Fotoquímicos , Poliestirenos/química , MicroRNAs/análise , Eletrodos , Polímeros/química
6.
Phytochemistry ; 222: 114067, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583852

RESUMO

1,2-diarylpropanes are a kind of abundant natural products formed by radical coupling. On account of molecular flexibility, it was challenged in the identifications of relative and absolute configurations of the 1,2-diarylpropanes. In this research, fourteen pairs of enantiomeric 1,2-diarylpropanes (1a/1b-14a/14b), comprising twelve previously undescribed pairs (1a/1b-4a/4b, 6a/6b-10a/10b, and 12a/12b-14a/14b), were isolated from the fruit of Crataegus pinnatifida. Their structures were determined through multiple NMR spectral analyses, empirical NMR rules, X-ray crystallography, and the comparison of experimental ECD spectra with calculated data. In addition, the analysis of ECD spectra revealed that substituent effects could generate an inverted chiroptical response, exhibiting in mirror-image ECD signals. This phenomenon was investigated by conformational analysis, molecular orbital analysis, the transition density matrix and hole/electron distributions. Moreover, a potential experimental rule was proposed for the rapid determination of the absolute configurations of the 1,2-diarylpropanes.


Assuntos
Crataegus , Frutas , Crataegus/química , Frutas/química , Estrutura Molecular , Estereoisomerismo , Conformação Molecular , Cristalografia por Raios X , Dicroísmo Circular , Modelos Moleculares , Espectroscopia de Ressonância Magnética
7.
J Integr Med ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38688809

RESUMO

BACKGROUND: Yiqi Peiyuan (YQPY) prescription, a composite prescription of traditional Chinese medicine, has been used to prevent or delay the continued deterioration of renal function after acute kidney injury (AKI) in some institutions and has shown considerable efficacy. OBJECTIVE: This is the first randomized controlled trial to assess efficacy and safety of YQPY for improving short-term prognosis in adult patients with AKI. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: This is a prospective, double-blind, multicenter, randomized, and placebo-controlled clinical trial. A total of 144 enrolled participants were randomly allocated to two groups according to a randomization schedule. Participants, caregivers and investigators assessing the outcomes were blinded to group assignment. Patients in the YQPY group received 36 g YQPY granules twice a day for 28 days. Patients in the placebo group received a placebo in the same dose as the YQPY granules. MAIN OUTCOME MEASURES: The primary outcome was the change in the estimated glomerular filtration rate (eGFR) between baseline and after 4 and 24 weeks of treatment. The secondary outcomes were the change of serum creatinine (Scr) level between baseline and after treatment, and the incidence of endpoint events, defined as eGFR increasing by more than 25% above baseline, eGFR >75 mL/min per 1.73 m2 or the composite endpoint, which was defined as the sum of patients meeting either of the above criteria. RESULTS: Data from a total of 114 patients (59 in the YQPY group and 55 in the control group) were analyzed. The mean changes in eGFR and Scr in weeks 4 and 24 had no difference between the two groups. In further subgroup analysis (22 in the YQPY group and 31 in the control group), the mean change in eGFR after treatment for 4 weeks was 27.39 mL/min per 1.73 m2 in the YQPY group and 5.78 mL/min per 1.73 m2 in the placebo group, and the mean difference between groups was 21.61 mL/min per 1.73 m2 (P <0.001). Thirteen (59.1%) patients in the YQPY group and 5 (16.1%) in the placebo group reached the composite endpoints (P = 0.002). During the intervention, 2 and 4 severe adverse events were reported in the YQPY and placebo groups, respectively. CONCLUSION: The YQPY granules can effectively improve the renal function of patients 4 weeks after the onset of AKI, indicating that it has good efficacy for improving short-term renal outcomes in patients with AKI. The YQPY granules may be a promising therapy for adults with AKI. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100051723. Please cite this article as: Wu JJ, Zhang TY, Qi YH, Zhu MY, Fang Y, Qi CJ, et al. Efficacy and safety of Yiqi Peiyuan granules for improving the short-term prognosis of patients with acute kidney injury: a multicenter, double-blind, placebo-controlled, randomized trial. J Integr Med. 2024; Epub ahead of print.

8.
J Mol Cell Cardiol ; 190: 62-75, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583797

RESUMO

Intimal hyperplasia is a complicated pathophysiological phenomenon attributable to in-stent restenosis, and the underlying mechanism remains unclear. Interleukin enhancer-binding factor 3 (ILF3), a double-stranded RNA-binding protein involved in regulating mRNA stability, has been recently demonstrated to assume a crucial role in cardiovascular disease; nevertheless, its impact on intimal hyperplasia remains unknown. In current study, we used samples of human restenotic arteries and rodent models of intimal hyperplasia, we found that vascular smooth muscle cell (VSMC) ILF3 expression was markedly elevated in human restenotic arteries and murine ligated carotid arteries. SMC-specific ILF3 knockout mice significantly suppressed injury induced neointimal formation. In vitro, platelet-derived growth factor type BB (PDGF-BB) treatment elevated the level of VSMC ILF3 in a dose- and time-dependent manner. ILF3 silencing markedly inhibited PDGF-BB-induced phenotype switching, proliferation, and migration in VSMCs. Transcriptome sequencing and RNA immunoprecipitation sequencing depicted that ILF3 maintained its stability upon binding to the mRNA of the high-mobility group box 1 protein (HMGB1), thereby exerting an inhibitory effect on the transcription of dual specificity phosphatase 16 (DUSP16) through enhanced phosphorylation of signal transducer and activator of transcription 3 (STAT3). Therefore, the results both in vitro and in vivo indicated that the loss of ILF3 in VSMC ameliorated neointimal hyperplasia by regulating the STAT3/DUSP16 axis through the degradation of HMGB1 mRNA. Our findings revealed that vascular injury activates VSMC ILF3, which in turn promotes intima formation. Consequently, targeting specific VSMC ILF3 may present a potential therapeutic strategy for ameliorating cardiovascular restenosis.


Assuntos
Proteína HMGB1 , Hiperplasia , Camundongos Knockout , Músculo Liso Vascular , Miócitos de Músculo Liso , Proteínas do Fator Nuclear 90 , Estabilidade de RNA , Fator de Transcrição STAT3 , Túnica Íntima , Animais , Humanos , Masculino , Camundongos , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Regulação da Expressão Gênica , Proteína HMGB1/metabolismo , Proteína HMGB1/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Neointima/metabolismo , Neointima/patologia , Proteínas do Fator Nuclear 90/metabolismo , Proteínas do Fator Nuclear 90/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Túnica Íntima/metabolismo , Túnica Íntima/patologia
9.
Eur Spine J ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526628

RESUMO

BACKGROUND: Neurofibromatosis type 1 (NF 1) is an autosomal-dominant tumor predisposition genetic disease affecting approximately 1 in 3000 live births. The condition could present various manifestations ranging from skin abnormalities to neurological tumors. The musculoskeletal system could also be frequently affected, and scoliosis is the most common orthopedic manifestation. Characterized by the early-onset and rapid progression tendency, NF 1-related dystrophic scoliosis presented discrepancies from idiopathic scoliosis in terms of natural history, clinical features, and management outcomes and thus required special attention. In the current study, the authors conducted a systemic review to outline the body of evidence of the natural history, clinical characteristics, surgical outcomes, and surgical complications of NF 1-induced scoliosis, aiming to provide an elucidative insight into this condition. METHOD: Systemic review and meta-analysis were conducted according to the latest Preferred Reporting Items for Systematic Reviews Meta-Analyses (PRISMA) guidelines. The search was performed in Medline, Embase, and Web of Science Core Collection up to December 27, 2022, using related keywords. Clinical features such as frequencies, segmental involvement, and hereditary information were summarized and described qualitatively. Meta-analysis was conducted using R software and the 'meta' package to yield an overall outcome of efficacy and safety of surgical management, precisely, spinal fusion procedure and growing rods procedure. Corrective rate of Cobb angle, sagittal kyphosis angle, and T1-S1 length post-operative and at the last follow-up was used to evaluate the efficacy, and the occurrence of surgery-related complications was used to evaluate the safety. RESULT: A total of 37 articles involving 1023 patients were included. Approximately 26.6% of the NF 1 patients would present with scoliosis. Patients tend to develop scoliosis at an earlier age. The thoracic part turned out to be the most affected segment. No obvious correlation between scoliosis and genotype or hereditary type was observed. Both spinal fusion and growing rod surgery have shown acceptable treatment outcomes, with spinal fusion demonstrating better performance in terms of effectiveness and safety. The growing rods technique seemed to allow a better lengthening of the spine. The mainstay post-operative complications were implant-related complications but could be managed with limited revision surgery. Severe neurological deficits were rarely reported. CONCLUSION: Scoliosis, especially the subtype characterized by dystrophic bony changes, is a significant orthopedic manifestation of NF1. It has an early onset, a tendency to persistently and rapidly progress, and is challenging to deal with. The current review outlines the available evidence from the perspective of natural history, clinical features, and the treatment efficacy and safety of the mainstay surgical options. Patients with NF1 scoliosis will benefit from a better understanding of the disease and evidence based treatment strategies.

10.
Eur J Ageing ; 21(1): 9, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502408

RESUMO

OBJECTIVE: Adequate sleep is closely related to people's health. However, with increasing age, the quality of sleep worsens. At the same time, among elderly individuals, frailty is also a disturbing factor, which makes elderly individuals more vulnerable to negative factors. To explore the relationship between the two, we conducted this study. METHODS: In this paper, independent genetic variations related to insomnia, sleep duration and daytime sleepiness were selected as IVs, and related genetic tools were used to search published genome-wide association studies for a two-sample Mendelian randomization (TSMR) analysis. The inverse-variance weighted (IVW) method was used as the main Mendelian randomization analysis method. Cochran's Q test was used to test heterogeneity, MR‒Egger was used to test horizontal pleiotropy, and the MR-PRESSO test was used to remove outliers. RESULTS: According to our research, insomnia (OR = 1.10, 95% CI 1.03-1.17, P = 2.59e-97), long sleep duration (OR = 0.66, 95% CI 0.37-1.17, P = 0.02), short sleep duration (OR = 1.30, 95% CI 1.22-1.38, P = 2.23e-17) and daytime sleepiness (OR = 1.49, 95% CI 1.25-1.77, P = 0.96e-4) had a bidirectional causal relationship with frailty. CONCLUSIONS: Our research showed that there is a causal relationship between sleep disturbances and frailty. This result was obtained by a TSMR analysis, which involves the use of genetic variation as an IV to determine causal relationships between exposure and outcome. Future TSMR studies should include a larger sample for analysis.

12.
Sci Total Environ ; 927: 172040, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554962

RESUMO

Civil airports are recognized as significant contributors to fine particulate matter, especially ultra-fine particulate matter (UFP). The pollutants from airport activities have a notable adverse impact on global climate, urban air quality, and public health. However, there is a lack of practical observational studies on the characterization of integrated pollutant emissions from large civil airports. This study aims to focus on the combined emission characteristics of particulate number concentration (PNC), size distribution, and components at a large civil airport, especially UFP. The findings reveal that airport activities significantly contribute to elevated PNC levels during aircraft activity in downwind conditions (four times higher than background levels) and upwind conditions (7.5 times higher). UFP dominates the PNC around the airport. The particle size distribution shows two peaks occurring around 10-30 nm and 60-80 nm. Notably, particles within the ranges of 17-29 nm and 57-101 nm account for 65.9 % and 12.0 % of the total PNC respectively. Aircraft landing has the greatest impact on particles sized between 6 and 17 nm while takeoff affects particles sized between 29 and 57 nm resulting in a respective increase in PNC by factors of approximately 3.27 and 35.4-fold increase compared to background levels. Different aircraft types exhibit varying effects on PNC with A320 and A321 showing more pronounced effects during takeoff and landing.The presence of airports leads to roughly five-fold rise in elemental component concentrations with Si being highest followed by OC, Ca, Al, Fe, Ca2+, EC, and Mg2+. The OC/EC ratio under high aircraft activity in downwind conditions falls within range of approximately 2.5-3.5. These characteristic components and ratio can be considered as identifying species for civil airports. PMF model show about 75 % of the particulate emissions at the airport boundary were related to airport activities.

13.
Pest Manag Sci ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459963

RESUMO

BACKGROUND: Resistance to dicamba in Chenopodium album was first documented over a decade ago, however, the molecular basis of dicamba resistance in this species has not been elucidated. In this research, the resistance mechanism in a dicamba-resistant C. album phenotype was investigated using a transcriptomics (RNA-sequence) approach. RESULTS: The dose-response assay showed that the resistant (R) phenotype was nearly 25-fold more resistant to dicamba than a susceptible (S) phenotype of C. album. Also, dicamba treatment significantly induced transcription of the known auxin-responsive genes, Gretchen Hagen 3 (GH3), small auxin-up RNAs (SAURs), and 1-aminocyclopropane-1-carboxylate synthase (ACS) genes in the susceptible phenotype. Comparing the transcripts of auxin TIR/AFB receptors and auxin/indole-3-acetic acid (AUX/IAA) proteins identified from C. album transcriptomic analysis revealed that the R phenotype contained a novel mutation at the first codon of the GWPPV degron motif of IAA16, resulting in an amino acid substitution of glycine (G) with aspartic acid (D). Sequencing the IAA16 gene in other R and S individuals further confirmed that all the R individuals contained the mutation. CONCLUSION: In this research, we describe the dicamba resistance mechanism in the only case of dicamba-resistant C. album reported to date. Prior work has shown that the dicamba resistance allele confers significant growth defects to the R phenotype investigated here, suggesting that dicamba-resistant C. album carrying this novel mutation in the IAA16 gene may not persist at high frequencies upon removal of dicamba application. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

14.
Huan Jing Ke Xue ; 45(3): 1793-1802, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471890

RESUMO

A rice pot experiment was conducted to identify the effect of silica fertilizer prepared from husk ash on the soil bioavailability of cadmium (Cd) and arsenic (As), enzyme activities, microbial community structure, and heavy metal content in brown rice at different growth stages. The results showed that the application of 0.1%-1.0% silica fertilizer-husk ash increased the pH value of soil by 0.04-0.24 units and the content of soil available silicon by 44.2%-97.5%. It also decreased the content of available Cd and available As by 16.2%-21.4% and 16.0%-24.9%, respectively. With the increase in application amount, the soil enzyme activities increased at all growth stages, and the sucrase activity and the dehydrogenase activity significantly increased by 6.3%-145.7% and 6.7%-224.1%, respectively. The analysis of the soil microbial community composition structure at mature stages showed that the application of silica fertilizer-husk ash had no effect on microbial α-diversity, but it had a significant effect on microbial ß-diversity and then promoted microbial growth and maintained the stability of the community structure. With the increase in application amount, the contents of Cd in brown rice decreased by 29.3%-89.7%, and the contents of total As and inorganic As in brown rice decreased by 7.8%-42.3% and 17.2%-44.5%, respectively. Under the application of 0.5% and 1.0% silica fertilizer-husk ash, the Cd contents in brown rice were lower than 0.2 mg·kg-1, and the inorganic As contents in brown rice were lower than 0.35 mg·kg-1. In conclusion, the silica fertilizer-husk ash can improve soil quality and reduce the contents of Cd and As in brown rice, and it is eco-friendly and can be used to remedy the paddy soil contaminated with Cd and As.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Cádmio/análise , Arsênio/análise , Dióxido de Silício , Solo/química , Oryza/química , Fertilizantes/análise , Poluentes do Solo/análise
15.
Huan Jing Ke Xue ; 45(2): 1118-1127, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471949

RESUMO

In this study, a field experiment was conducted to examine the effects of the application of irrigation water containing Zn at the key growth period (booting stage and filling stage) on exchangeable Cd content in the soil, Cd concentration in pore water, and Cd uptake and transport in rice in a Cd-contaminated paddy field in Liuyang City, Hunan Province. The results indicated that: ① the application of irrigation water containing Zn during the key growth period could inhibit the releasing process of exchangeable Cd from the soil into pore water. Compared with that in the control, the content of exchangeable Cd in soil was slightly changed, but the concentration of Cd in soil pore water at the mature stage was significantly reduced by 16.7%-57.6%. ② The application of irrigation water containing Zn at the key growth period could significantly reduce the Cd content in various parts of rice. Cd contents in root, stem, and brown rice with the application of irrigation water containing 20 mg·L-1 Zn before the booting and the filling stage (BF1) were significantly decreased by 56.0%, 83.8%, and 85.2%, respectively. ③ Compared with the application of 100 mg·L-1 irrigation water containing Zn, the application of 20 mg·L-1 irrigation water containing Zn significantly reduced the uptake and transport of Cd in rice, and the translocation factor (TF) of Cd from rice roots to stems was also significantly reduced by 12.5%-56.3%, with the B1 and BF1 treatments reaching significant levels. These results suggested that the application of irrigation water containing Zn could significantly reduce the uptake and accumulation of Cd in rice, and the application of 20 mg·L-1 irrigation water containing Zn before the booting and filling stage could effectively realize the safe production of Cd-contaminated paddy fields.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Poluentes do Solo/análise , Solo , Água , Zinco
16.
J Am Chem Soc ; 146(10): 6974-6982, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38417031

RESUMO

The two-dimensional (2D) perovskites have drawn intensive attention due to their unique stability and outstanding optoelectronic properties. However, the debate surrounding the spatial phase distribution and band alignment among different 2D phases in the quasi-2D perovskite has created complexities in understanding the carrier dynamics, hindering material and device development. In this study, we employed highly sensitive transient absorption spectroscopy to investigate the carrier dynamics of (BA)2(MA)n-1PbnI3n+1 quasi-2D Ruddlesden-Popper perovskite thin films, nominally prepared as n = 4. We observed the carrier-density-dependent electron and hole transfer dynamics between the 2D and three-dimensional (3D) phases. Under a low carrier density within the linear response range, we successfully resolved three ultrafast processes of both electron and hole transfers, spanning from hundreds of femtoseconds to several picoseconds, tens to hundreds of picoseconds, and hundreds of picoseconds to several nanoseconds, which can be attributed to lateral-epitaxial, partial-epitaxial, and disordered-interface heterostructures between 2D and 3D phases. By considering the interplay among the phase structure, band alignment, and carrier dynamics, we have proposed material synthesis strategies aimed at enhancing the carrier transport. Our results not only provide deep insights into an accurate intrinsic photophysics of quasi-2D perovskites but also inspire advancements in the practical application of these materials.

17.
Neuroscience ; 542: 33-46, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38354901

RESUMO

The forkhead box protein P2 (Foxp2), initially identified for its role in speech and language development, plays an important role in neural development. Previous studies investigated the function of the Foxp2 gene by deleting or mutating Foxp2 from developmental stages. Little is known about its physiological function in adult brains. Although Foxp2 has been well studied in the dorsal striatum, its function in the nucleus accumbens (NAc) of the ventral striatum remains elusive. Here, we examine the physiological function of Foxp2 in NAc of mouse brains. We conditionally knocked out Foxp2 by microinjections of AAV-EGFP-Cre viruses into the medial shell of NAc of Foxp2 floxed (cKO) mice. Immunostaining showed increased c-Fos positive cells in cKO NAc at basal levels, suggesting an abnormality in Foxp2-deficient NAc cells. Unbiased behavioral profiling of Foxp2 cKO mice showed abnormalities in limbic-associated function. Foxp2 cKO mice exhibited abnormal social novelty without preference for interaction with strangers and familiar mice. In appetitive reward learning, Foxp2 cKO mice failed to learn the time expectancy of food delivery. In fear learning, Foxp2 cKO mice exhibited abnormal increases in freezing levels in response to tone paired with foot shock during fear conditioning. The extinction of the fear response was also altered in Foxp2 cKO mice. In contrast, conditional knockout of Foxp2 in NAc did not affect locomotion, motor coordination, thermal pain sensation, anxiety- and depression-like behaviors. Collectively, our study suggests that Foxp2 has a multifaceted physiological role in NAc in the regulation of limbic function in the adult brain.


Assuntos
Aprendizagem , Núcleo Accumbens , Camundongos , Animais , Núcleo Accumbens/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Proteínas Repressoras/metabolismo
18.
J Phys Chem Lett ; 15(9): 2470-2475, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38407037

RESUMO

Sum-frequency generation (SFG) vibrational spectroscopy is an invaluable tool in surface science, known for its specificity to surfaces and interfaces. Despite its wide application, it is often hampered by weak signal detection. Here, we present an innovative enhancement technique of postsample amplification, using a picosecond noncollinear optical parametric amplifier (NOPA). We conducted a systematical investigation into the impact of different intensities of pump and SFG seed light, as the input signal in NOPA, and demonstrated this method on the octadecanethiol (ODT) molecules on gold films. The amplified SFG by NOPA reproduced the SFG vibrational spectra, enhanced by about 4 orders of magnitude but with broader spectral resolution due to the short pulse width of the pump light in NOPA. This study makes it possible to realize highly sensitive SFG measurements, marking a significant advancement in spectroscopic analysis techniques.

19.
Angew Chem Int Ed Engl ; 63(16): e202401103, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412017

RESUMO

Singlet fission (SF) holds great promise for current photovoltaic technologies, where tetracenes, with their relatively high triplet energies, play a major role for application in silicon-based solar cells. However, the SF efficiencies in tetracene dimers are low due to the unfavorable energetics of their singlet and triplet energy levels. In the solid state, tetracene exhibits high yields of triplet formation through SF, raising great interest about the underlying mechanisms. To address this discrepancy, we designed and prepared a novel molecular system based on a hexaphenylbenzene core decorated with 2 to 6 tetracene chromophores. The spatial arrangement of tetracene units, induced by steric hindrance in the central part, dictates through-space coupling, making it a relevant model for solid-state chromophore organization. We then revealed a remarkable increase in SF quantum yield with the number of tetracenes, reaching quantitative (196 %) triplet pair formation in hexamer. We observed a short-lived correlated triplet pair and limited magnetic effects, indicating ineffective triplet dissociation in these through-space coupled systems. These findings emphasize the crucial role of the number of chromophores involved and the interchromophore arrangement for the SF efficiency. The insights gained from this study will aid designing more efficient and technology-compatible SF systems for applications in photovoltaics.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...