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Adolescents are high-risk population for major depressive disorder. Executive dysfunction emerges as a common feature of depression and exerts a significant influence on the social functionality of adolescents. This study aimed to identify the multimodal co-varying brain network related to executive function in adolescent with major depressive disorder. A total of 24 adolescent major depressive disorder patients and 43 healthy controls were included and completed the Intra-Extra Dimensional Set Shift Task. Multimodal neuroimaging data, including the amplitude of low-frequency fluctuations from resting-state functional magnetic resonance imaging and gray matter volume from structural magnetic resonance imaging, were combined with executive function using a supervised fusion method named multimodal canonical correlation analysis with reference plus joint independent component analysis. The major depressive disorder showed more total errors than the healthy controls in the Intra-Extra Dimensional Set Shift task. Their performance on the Intra-Extra Dimensional Set Shift Task was negatively related to the 14-item Hamilton Rating Scale for Anxiety score. We discovered an executive function-related multimodal fronto-occipito-temporal network with lower amplitude of low-frequency fluctuation and gray matter volume loadings in major depressive disorder. The gray matter component of the identified network was negatively related to errors made in Intra-Extra Dimensional Set Shift while positively related to stages completed. These findings may help to deepen our understanding of the pathophysiological mechanisms of cognitive dysfunction in adolescent depression.
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Transtorno Depressivo Maior , Função Executiva , Imageamento por Ressonância Magnética , Imagem Multimodal , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/fisiopatologia , Adolescente , Função Executiva/fisiologia , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Neuroimagem/métodos , Cognição/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos , Mapeamento Encefálico/métodosRESUMO
Rapid construction of new fluorescence emitters is essential in advancing synthetic luminescent materials. This study illustrated a piperidine-promoted reaction of chiral dialdehyde with benzoylacetonitrile and malonitrile, leading to the formation of the 6/6/7 fused cyclic product in good yield. The proposed reaction mechanism involves a dual condensation/cyclization process, achieving the formation of up to six bonds for fused polycycles. The single crystal structure analysis revealed that the fused cyclic skeleton contains face-to-face naphthyl and cyanoalkenyl motifs, which act as the electronic donor and acceptor, respectively, potentially resulting in through-space charge transfer (TSCT) emission. While the TSCT emissions were weak in solution, a notable increase in luminescence intensity was observed upon aggregation, indicating bright fluorescent light. A series of theoretical analyses further supported the possibility of spatial electronic communication based on frontier molecular orbitals, the distance of charge transfer, and reduced density gradient analysis. This work not only provides guidance for the one-step synthesis of complex polycycles, but also offers valuable insights into the design of aggregation-enhanced TSCT emission materials.
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Rheumatoid arthritis (RA) is a complicated chronic disorder of the immune system, featured with severe inflammatory joints, synovium hyperplasia, articular cartilage, and bone damage. In the RA microenvironment, RA-involved cells, overproduced nitric oxide (NO), and pro-inflammatory cytokines are highly interplayed and mutually reinforced, which form a vicious circle and play crucial roles in the formation and progression of RA. To comprehensively break the vicious circle and obtain the maximum benefits, we have developed neutrophil membrane-camouflaged NO scavenging nanoparticles based on an NO-responsive hyaluronic acid derivative for delivery of MTX. These multifunctional nanoparticles (NNO-NPs/MTX), by inheriting the membrane functions of the source cells, possess prolonged circulation and specific localization at the inflamed sites when administrated in the body. Remarkably, NNO-NPs/MTX can neutralize the pro-inflammatory cytokines via the outer membrane receptors, scavenge NO, and be responsively disassociated to release MTX for RA-involved cell regulation and HA for lubrication in the RA sites. In a collagen-induced arthritis mouse model, NNO-NPs/MTX exhibits a significant anti-inflammation effect and effectively alleviates the characteristic RA symptoms such as synovial hyperplasia and cartilage destruction, realizing the synergistic and boosted therapeutic outcome against intractable RA. Thus, NNO-NPs/MTX provides a promising and potent platform to integrately treat RA.
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Artrite Reumatoide , Ácido Hialurônico , Metotrexato , Óxido Nítrico , Ácido Hialurônico/química , Animais , Artrite Reumatoide/tratamento farmacológico , Camundongos , Metotrexato/farmacologia , Metotrexato/administração & dosagem , Metotrexato/química , Óxido Nítrico/metabolismo , Nanopartículas/química , Humanos , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas Multifuncionais/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologiaRESUMO
BACKGROUND: Low concentrations of S100B have neurotrophic effects and can promote nerve growth and repair, which plays an essential role in the pathophysiological and histopathological alterations of major depressive disorder (MDD) during disease development. Studies have shown that plasma S100B levels are altered in patients with MDD. In this study, we investigated whether the plasma S100B levels in MDD differ between genders. METHODS: We studied 235 healthy controls (HCs) (90 males and 145 females) and 185 MDD patients (65 males and 120 females). Plasma S100B levels were detected via multifactor assay. The Mahalanobis distance method was used to detect the outliers of plasma S100B levels in the HC and MDD groups. The Kolmogorov-Smirnov test was used to test the normality of six groups of S100B samples. The Mann-Whitney test and Scheirer-Ray-Hare test were used for the comparison of S100B between diagnoses and genders, and the presence of a relationship between plasma S100B levels and demographic details or clinical traits was assessed using Spearman correlation analysis. RESULTS: All individuals in the HC group had plasma S100B levels that were significantly greater than those in the MDD group. In the MDD group, males presented significantly higher plasma S100B levels than females. In the male group, the plasma S100B levels in the HC group were significantly higher than those in the MDD group, while in the female group, no significant difference was found between the HC and MDD groups. In the male MDD subgroup, there was a positive correlation between plasma S100B levels and years of education. In the female MDD subgroup, there were negative correlations between plasma S100B levels and age and suicidal ideation. CONCLUSIONS: In summary, plasma S100B levels vary with gender and are decreased in MDD patients, which may be related to pathological alterations in glial cells.
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Transtorno Depressivo Maior , Subunidade beta da Proteína Ligante de Cálcio S100 , Humanos , Transtorno Depressivo Maior/sangue , Masculino , Feminino , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Adulto , Fatores Sexuais , Pessoa de Meia-Idade , Caracteres Sexuais , Biomarcadores/sangue , Estudos de Casos e ControlesRESUMO
The combination of immune checkpoint inhibitors and immunogenic cell death (ICD) inducers has become a promising strategy for the treatment of various cancers. However, its efficacy remains unmet because of the dense stroma and defective vasculatures in the tumor microenvironment (TME) that restricts the intratumoral infiltration of cytotoxic T lymphocytes (CTLs). Herein, cancer-associated fibroblasts (CAFs)-targeted nanoemulsions are tailored to combine the ICD induction and the TME reprogramming to sensitize checkpoint blockade immunotherapy. Melittin, as an ICD inducer and an antifibrotic agent, is efficiently encapsulated into the nanoemulsion accompanied by a nitric oxide donor to improve its bioavailability and tumor targeting. The nanoemulsions exhibited dual functionality by directly inducing direct cancer cell death and enhancing the tumoral immunogenicity, while also synergistically reprogramming the TME through reversing the activated CAFs, decreasing collagen deposition and restoring tumor vessels. Consequently, these nanemulsions successfully facilitated the CTLs infiltration and suppressing the recruitment of immunosuppressive cells. A combination of AE-MGNPs and anti-CTLA-4 antibody greatly elicited a striking level of antitumor T-cell response to suppress tumor growth in CAFs-rich colorectal tumor models. Our work emphasized the integration of the ICD induction with simultaneous modulation of the TME to enhance the sensitivity of patients to checkpoint blockade immunotherapy.
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Antineoplásicos , Neoplasias Colorretais , Neoplasias , Humanos , Microambiente Tumoral , Inibidores de Checkpoint Imunológico/farmacologia , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Imunoterapia , Linhagem Celular TumoralRESUMO
BACKGROUND: Antepartum depression has been reported to be associated with the intensity of maternal prenatal noise exposure; however, the association between noise exposure duration and the development of antepartum depression has not been established. This study aimed to determine the total and trimester-specific association of prenatal noise exposure duration with the development of antepartum depression. METHODS: From May 2018 to June 2021, we recruited 2,166 pregnant women from Shengjing Hospital, northeast China. We used a standardized questionnaire to assess women's prenatal noise exposure and used the Edinburgh Postnatal Depression Scale to assess pregnant women's antepartum depression during the 1st -, 2nd -, and 3rd - trimesters. We calculated a cumulative noise exposure score ranging from 0 to 3, with a higher score reflecting higher frequency and longer duration of noise exposure during pregnancy. RESULTS: Women who were exposed to noise for ≥ 15 min per day had an increased risk of antepartum depression compared with women who were not exposed to noise during pregnancy [odds ratio (OR) = 1.83, 95%CI:1.18, 2.83]. Noise exposure in a specific trimester was associated with higher risk of depression in the same trimester and subsequent trimesters. We observed increases in antepartum depression risk with increasing cumulative noise exposure scores (P for trend < 0.05 for all). Pregnant women with the highest scores had the highest risk of antepartum depression during the first (OR = 1.30, 95%CI:1.02, 1.65), second (OR = 1.75, 95%CI:1.23, 2.50) trimesters. Women with a cumulative noise exposure score of 2 had the highest risk of antepartum depression during the third trimester (OR = 1.79, 95%CI:1.14, 2.80), as well as during the whole pregnancy (OR = 1.94, 95%CI:1.14, 3.30). CONCLUSIONS: Maternal prenatal noise exposure duration was positively associated with antepartum depression risk in a dose-response manner. It is necessary to develop strategies by which pregnant women can avoid excessive exposure to noise to prevent antepartum depression.
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Depressão Pós-Parto , Depressão , Ruído , Feminino , Humanos , Gravidez , Depressão/etiologia , Depressão/complicações , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/etiologia , Exposição Materna , Terceiro Trimestre da Gravidez , Trimestres da Gravidez , Gestantes , Ruído/efeitos adversosRESUMO
OBJECTIVES: To investigate the effect of topical 0.05% cyclosporine A (CsA) eye drops as an adjunct to conventional therapy in maintaining post-femtosecond-assisted laser in situ keratomileusis (FS-LASIK) ocular surface stability. METHODS: Sixty-six patients (eyes) undergoing FS-LASIK were randomized into 2 groups: 33 patients (eyes) in group I (conventional treatment group) and 33 patients (eyes) in group II (CsA group). Conventional treatments include topical levofloxacin, fluorometholone, and artificial tears. Group II received topical 0.05% CsA eye drops twice daily for three months in addition to conventional treatment. Ocular Surface Disease Index (OSDI), numerical rating scale (NRS), tear break-up time (TBUT), Schirmer I test (SIt), corneal fluorescein staining (CFS), conjunctival lissamine green (LG) staining, corneal sensitivity, and corneal nerve morphology were measured. In addition, tear inflammatory cytokine levels were measured using the Luminex assay. Follow-up was performed preoperatively and 1 and 3 months postoperatively. RESULTS: In the CsA group, OSDI, TBUT, LG, corneal sensitivity, and corneal nerve fiber total branch density recovered better than in the conventional treatment group. As for tear inflammatory cytokines, interferon (INF) -γ, interleukin (IL)-10, and IL-6 levels were significantly higher in the conventional treatment group as compared with the CsA group. In addition, no significant differences in NRS, SIt, and CFS scores were observed between the two groups. CONCLUSION: In conclusion, 0.05% CsA eye drops is a useful adjunct to conventional treatment for restoring the ocular surface stability after corneal refractive surgery and is more potent in sustaining anti-inflammatory effects.
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Córnea , Ciclosporina , Imunossupressores , Ceratomileuse Assistida por Excimer Laser In Situ , Soluções Oftálmicas , Lágrimas , Humanos , Ciclosporina/administração & dosagem , Masculino , Soluções Oftálmicas/administração & dosagem , Feminino , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Adulto , Lágrimas/metabolismo , Imunossupressores/administração & dosagem , Adulto Jovem , Córnea/efeitos dos fármacos , Síndromes do Olho Seco/tratamento farmacológico , Miopia/cirurgia , Miopia/tratamento farmacológico , Lasers de Excimer/uso terapêutico , Estudos Prospectivos , Administração TópicaRESUMO
The unprecedented navigation ability in micro/nanoscale and tailored functionality tunes micro/nanomotors as new target drug delivery systems, open up new horizons for biomedical applications. Herein, we designed a light-driven rGO/Cu2 + 1O tubular nanomotor for active targeting of cancer cells as a drug delivery system. The propulsion performance is greatly enhanced in real cell media (5% glucose cells isotonic solution), attributing to the introduction of oxygen vacancy and reduced graphene oxide (rGO) layer for separating photo-induced electron-hole pairs. The motion speed and direction can be readily modulated. Meanwhile, doxorubicin (DOX) can be loaded quickly on the rGO layer because of π-π bonding effect. The Cu2 + 1O matrix in the tiny robots not only serves as a photocatalyst to generate a chemical concentration gradient as the driving force but also acts as a nanomedicine to kill cancer cells as well. The strong propulsion of light-driven rGO/Cu2 + 1O nanomotors coupled with tiny size endow them with active transmembrane transport, assisting DOX and Cu2 + 1O breaking through the barrier of the cell membrane. Compared with non-powered nanocarrier and free DOX, light-propelled rGO/Cu2 + 1O nanomotors exhibit greater transmembrane transport efficiency and significant therapeutic efficacy. This proof-of-concept nanomotor design presents an innovative approach against tumor, enlarging the list of biomedical applications of light-driven micro/nanomotors to the superficial tissue treatment.
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Cobre , Doxorrubicina , Grafite , Luz , Cobre/química , Humanos , Doxorrubicina/farmacologia , Doxorrubicina/química , Grafite/química , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Portadores de Fármacos/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Linhagem Celular TumoralRESUMO
As a plant-specific endoreplication regulator, the SIAMESE-RELATED (SMR) family (a cyclin-dependent kinase inhibitor) plays an important role in plant growth and development and resistance to stress. Although the genes of the maize (Zea mays) SMR family have been studied extensively, the ZmSMR10 (Zm00001eb231280) gene has not been reported. In this study, the function of this gene was characterized by overexpression and silencing. Compared with the control, the transgenic plants exhibited the phenotypes of early maturation, dwarfing, and drought resistance. Expression of the protein in prokaryotes demonstrates that ZmSMR10 is a small protein, and the results of subcellular localization suggest that it travels functionally in the nucleus. Unlike ZmSMR4, yeast two-hybrid experiments demonstrated that ZmSMR10 does not interact strongly with with some cell cycle protein-dependent protein kinase (CDK) family members ZmCDKA;1/ZmCDKA;3/ZmCDKB1;1. Instead, it interacts strongly with ZmPCNA2 and ZmCSN5B. Based on these results, we concluded that ZmSMR10 is involved in the regulation of endoreplication through the interaction of ZmPCNA2 and ZmCSN5B. These findings provide a theoretical basis to understand the mechanism of the regulation of endoreplication and improve the yield of maize through the use of molecular techniques.
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Arabidopsis , Endorreduplicação , Arabidopsis/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas , Zea mays/genética , Zea mays/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , SecasRESUMO
In the development of ultra-deep wells, extremely high temperatures can lead to inefficiency of additives in drilling fluids. Hence, there is a need to prepare additives with a simple preparation process and good effects at ultra-high temperatures to ensure stable drilling fluid performance. In this study, a high temperature resistant filtration loss polymer (LY-2) was prepared using γ-methacryloyloxypropyltrimethoxysilane (KH570), N,N-dimethylallyl ammonium chloride (DMDAAC), sodium p-styrenesulfonate (SSS), and ß-cyclodextrin (ß-CD). The impact of the different monomer ratios on particle size, rheology, and filtration performance was systematically investigated. Infrared spectroscopy afforded the structural features. Thermogravimetric Analysis detected the temperature stability, and scanning electron microscopy characterized the polymer micromorphology. LY-2 was completely decomposed at a temperature above 600 °C. Experiments showed FLAPI of the drilling fluid containing 3% LY-2 aged at 260 °C/16 h was only 5.1 mL, which is 85.4% lower compared to the base fluid. This is attributed to the synergistic effect of the polymer adsorption through chemical action at high temperatures and the blocking effect of carbon nanoparticles on the filter cake released by cyclodextrin carbonization at high temperatures. Comparing LY-2 with commercial filter loss reducers shows that LY-2 has excellent temperature resistance, which exhibited five times higher filtration performance and relatively low cost, making it possible to be applied to ultra-high temperature drilling operations in an industrial scale-up.
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Major Depressive Disorder (MDD) is a complex mental disorder that involves alterations in signal transmission across multiple scales and structural abnormalities. The development of effective antidepressants (ADs) has been hindered by the dominance of monoamine hypothesis, resulting in slow progress. Traditional ADs have undesirable traits like delayed onset of action, limited efficacy, and severe side effects. Recently, two categories of fast-acting antidepressant compounds have surfaced, dissociative anesthetics S-ketamine and its metabolites, as well as psychedelics such as lysergic acid diethylamide (LSD). This has led to structural research and drug development of the receptors that they target. This review provides breakthroughs and achievements in the structure of depression-related receptors and novel ADs based on these. Cryo-electron microscopy (cryo-EM) has enabled researchers to identify the structures of membrane receptors, including the N-methyl-D-aspartate receptor (NMDAR) and the 5-hydroxytryptamine 2A (5-HT2A) receptor. These high-resolution structures can be used for the development of novel ADs using virtual drug screening (VDS). Moreover, the unique antidepressant effects of 5-HT1A receptors in various brain regions, and the pivotal roles of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and tyrosine kinase receptor 2 (TrkB) in regulating synaptic plasticity, emphasize their potential as therapeutic targets. Using structural information, a series of highly selective ADs were designed based on the different role of receptors in MDD. These molecules have the favorable characteristics of rapid onset and low adverse drug reactions. This review offers researchers guidance and a methodological framework for the structure-based design of ADs.
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Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Serotonina , Estrutura Molecular , Microscopia Crioeletrônica , Antidepressivos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismoRESUMO
Visible light-driven photocatalytic deracemization is highly esteemed as an ideal tool for organic synthesis due to its exceptional atom economy and synthetic efficiency. Consequently, successful instances of deracemization of allenes have been established, where the activated energy of photosensitizer should surpass that of the substrates, representing an intrinsic requirement. Accordingly, this method is not applicable for axially chiral molecules with significantly high triplet energies. In this study, we present a photoredox catalytic deracemization approach that enables the efficient synthesis of valuable yet challenging-to-access axially chiral 2-azaarene-functionalized quinazolinones. The substrate scope is extensive, allowing for both 3-axis and unmet 1-axis assembly through facile oxidation of diverse central chiral 2,3-dihydroquinazolin-4(1H)-ones that can be easily prepared and achieve enantiomer enrichment via deracemization. Mechanistic studies reveal the importance of photosensitizer selection in attaining excellent chemoselectivity and highlight the indispensability of a chiral Brønsted acid in enabling highly enantioselective protonation to accomplish efficient deracemization.
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Based on panel data from 2011 to 2019 for heavily polluting listed firms in the manufacturing industry, this paper examines the impact of environmental taxes on technological innovation and firm performance using the propensity score matching (PSM) and differences-in-differences (DID) methods. The empirical results show the following: (i) Firm performance and innovation quantity are positively affected by environmental taxes. The average effects of environmental taxes on firm performance and innovation quantity are 1.28 and 0.219, respectively. However, environmental taxes have no significant impact on innovation quality. (ii) A mechanism analysis reveals that innovation quantity plays a significant partial mediating role in the positive effect of environmental taxes on firm performance. (iii) Heterogeneity analysis shows that different environmental tax rates lead to a variation in innovation quantity and firm performance across regions. The positive effect of environmental taxes on innovation quantity is only confirmed in high-tax and low-tax areas. Meanwhile, high environmental taxes are related to better firm performance. Based on the research, policy recommendations are put forward to optimise environmental taxes, such as improving the environmental tax system and coordinating environmental tax and innovation policies.
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We presented a NIR-driven Janus Cu2O/Au nanomotor. The nanomotor has a truncated octahedral structure. By asymmetric Au evaporation, the light response range of Cu2O nanomotor is extended to near-infrared range, and the speed of Cu2O/Au nanomotors under NIR is significantly increased. In promoting apoptosis of hepatocellular carcinoma, except the nanotoxicity of Cu2O itself, the Au layer enhances the photothermal properties, allowing Cu2O/Au nanomotors to induce apoptosis in hepatocellular carcinoma cells by heating them. On the other hand, a Schottky barrier formed at the interface of Cu2O and Au, preventing the recombination of electrons, which makes more electrons react with biomolecules to produce toxic ROS to kill hepatocellular cells. The killing rate of hepatocellular carcinoma cells reached 87 % by the combined effect of nanotoxicity inhibition of proliferation and photothermal & photodynamic therapy (PTT & PDT). Nanomotors in combination with multiple approaches are explored as a new treatment to tumor in this article.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias/terapia , Linhagem Celular , Neoplasias Hepáticas/tratamento farmacológicoRESUMO
Visible-light-driven photoredox catalysis is known to be a powerful tool for organic synthesis. Its occurrence critically depends on the twice exothermic single-electron transfer processes of photosensitizers, which are governed by the redox properties of the species involved. Hence, the inherently narrow range of redox potentials of photosensitizers inevitably constrains their further availability. Sensitization-initiated electron transfer has recently been found to effectively overcome this substantial challenge. However, feasible and practical strategies for designing such complicated catalytic systems are rather scarce. Herein we report an elaborate dual-catalyst platform, with dicyanopyrazine as a visible light photosensitizer and a pyrenyl-incorporated chiral phosphoric acid as a co-sensitizer, and we demonstrate the applicability of this sensitization-initiated electron transfer strategy in an asymmetric formal de Mayo-type reaction. The catalysis platform enables otherwise thermodynamically unfavourable electron transfer processes to close the redox cycle and allows for precise access to valuable enantioenriched 1,5-diketones with a wide substrate range.
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The extensive utilization in food industry of pea protein is often impeded by its low water solubility, resulting in poor functional properties. Various methods, including pH-shifting (PS), ultrasonication (US), high-pressure micro-fluidization (MF), pH-shifting combined with ultrasonication (PS-US), and pH-shifting with micro-fluidization (PS-MF), were utilized to modify pea protein isolate (PPI) in order to enhance its functionality in emulsion formulation. The physicochemical properties and structural changes of the protein were investigated by assessing solubility, particle size, surface charge, protein profile, surface hydrophobicity, free sulfhydryl groups, and secondary structure content. The extent of modification induced by each treatment method on PPI-stabilized emulsions was compared based on parameters such as adsorbed interfacial protein concentration, particle size, zeta potential, and microstructure of the prepared emulsions. All modification increased the solubility of pea protein in the sequence of PS (4-fold) < MF (7-fold) < US (11-fold) < PS-US (13-fold) < PS-MF (14-fold). For single treatments, proteins dissolved more readily under US, resulting in the most uniform emulsions with small particle. The combined processes of PS-US and PS-MF further improved solubility, decreased emulsions particle size, promoted uniformity of emulsions. PS-US-stabilized emulsions displayed more smaller droplet size, narrower size distribution, and slightly higher stability than those prepared by PS-MF. The relatively higher emulsifying capacity of PPI treated by PS-US than those by PS-MF may be attributed to its higher surface hydrophobicity.
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Emulsões , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Proteínas de Ervilha , Solubilidade , Emulsões/química , Proteínas de Ervilha/química , Concentração de Íons de Hidrogênio , Pisum sativum/química , Sonicação , Estrutura Secundária de Proteína , Manipulação de Alimentos/métodosRESUMO
The aim of this study was to reveal the stoichiometric characteristics of carbon, nitrogen and phosphorus in rhizosphere and non-rhizosphere soils of Pinus sylvestris var. mongolica in the Hulunbuir desert. We investigated the contents and stoichiometry of organic carbon, total nitrogen, and total phosphorus contents of rhizosphere and non-rhizosphere soils across different stand ages (28, 37 and 46 a) of P. sylvestris var. mongolica plantations, with P. sylvestris var. mongolica natural forest as the control. We analyzed the correlation between soils properties and soil stoichiometry. The results showed that rhizosphere effect significantly affected soil N:P, and stand age significantly affected soil organic carbon content in P. sylvestris var. mongolica plantation. Soil organic carbon content in plantation was significantly lower than that in natural forest. Soil organic carbon and total nitrogen contents of plantations in both rhizosphere and non-rhizosphere soils firstly decreased and then increased with increasing stand age, while total phosphorus firstly increased and then decreased in rhizosphere soils, and firstly decreased and then increased in non-rhizosphere soils. There was significant positive correlations between C:N and C:P in rhizosphere soils but not in non-rhizosphere soils, suggesting that higher synergistic rhizosphere soil N and P limitation. The mean N:P values of rhizosphere and non-rhizosphere soils were 4.98 and 8.40, respectively, indicating that the growth of P. sylvestris var. mongolica was restricted by soil N and the rhizosphere soils were more N-restricted. The C:N:P stoichiometry of rhizosphere and non-rhizosphere soils were significantly influenced by soil properties, with available phosphorus being the most important driver. The growth of P. sylvestris var. mongolica was limited by N in the Hulunbuir desert, and root system played an obvious role in enriching and maintaining soil nutrients. It was recommended that soil nitrogen should be supplemented appropriately during the growth stage of P. sylvestris var. mongolica plantation, and phosphorus should be supplemented appropriately according to the synergistic nature of nitrogen and phosphorus limitation.
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Carbono , Nitrogênio , Fósforo , Pinus sylvestris , Rizosfera , Solo , Fósforo/análise , Nitrogênio/análise , Solo/química , Carbono/análise , Pinus sylvestris/crescimento & desenvolvimento , Florestas , China , Raízes de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimentoRESUMO
Global warming has led to severe land desertification on the Mongolian plateau. It puts great environmental pressure on vegetation communities. This pressure leads to fragmentation of land use and landscape patterns, thus triggering changes in the spatial distribution patterns of vegetation. The spatial distribution pattern of vegetation is crucial for the performance of its ecosystem services. However, there is not enough research on the relationship between large-scale spatial distribution patterns of vegetation and ecosystem services. Therefore, this study is to construct an ecological spatial network on the Mongolian Plateau based on landscape ecology and complex network theory. Combining pattern analysis methods to analyze the network, we obtained the spatial and temporal trends of forest and grass spatial distribution patterns from 2000 to 2100, and explored the relationship between the topological properties of source patches and ecosystem services in different patterns. It was found that there are four basic patterns of spatial distribution of forest and grass in the Mongolian Plateau. The Core-Linked Ring pattern accounts for 40.74 % and exhibits the highest stability. Under the SSP5-RCP8.5 scenario, source patches are reduced by 22.76 % in 2100. Topological indicators of source patches showed significant correlations with ecosystem services. For example, the CUE of grassland patches in the Centralized Star pattern was positively correlated with betweeness centrality. The most significant improvement in WUE after optimization is 19.90 % compared to pre-optimization. The conclusion of the study shows that the spatial distribution pattern of vegetation can be used to enhance the stability of ecological spatial network and improve ecosystem services at a larger scale. It can provide a certain reference for the study of spatial patterns of vegetation distribution in arid and semi-arid areas.
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Microbial nitrogen (N) removal is crucial for purifying surface water quality in paddy irrigation and drainage units (IDUs). However, the spatiotemporal microbial N removal potential characteristics within these IDUs and the effects of changing anaerobic conditions on this potential remain insufficiently studied. In this study, we investigated the microbial N removal potential of conventional rice-wheat rotation and anaerobically enhanced rice-crayfish rotation IDUs using field measurements, isotope tracing techniques, and quantitative PCR. Our findings reveal that paddy fields were identified as hotspots for anammox activity, contributing to 76.0 %-97.4 % of the total anammox N removal potential in the IDU, while denitrification processes in ditches accounted for 43.5 %-77.4 % of the IDU's denitrification potential. During the rice transplanting period, the anammox N removal potential peaked, representing 35.8 % and 71.8 % of the total anammox N removal potential of the paddy fields in rice-wheat and rice-crayfish IDUs, respectively. An increase in anaerobic conditions diminished the anammox N removal potential while amplifying denitrification capabilities. The N removal potential in paddy fields decreased with increasing depth, contrasting with the relative stability in ditches. Spatiotemporal fluctuations in N removal potentials within these units are influenced by Fe2+ concentration, carbon and N content, WFPS, and pH levels. This study provides a scientific basis for improving nitrogen removal and water quality treatment in IDUs.
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Recently, bioinspired fluorescent materials have drawn ever-increasing attention due to their ecofriendliness and easy accessibility. Herein, we demonstrate that anthraquinone/metal ion coordination complexes can form well-defined crystals and possess obvious fluorescence enhancement properties. The fluorescence quantum yields of anthraquinone/metal ion assemblies are more than 2 orders of magnitude compared to those of anthraquinone assemblies. The electronic structures of the first excited singlet states of anthraquinone/metal ion molecules are obtained, and the mechanism of the fluorescence enhancement is elucidated. Such photoluminescent anthraquinone/metal ion crystals can be considered as efficient phosphors in fabricating light-emitting diodes. This work provides a simple route for the development of highly efficient natural fluorescent materials.