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1.
Ecol Appl ; : e2969, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38562107

RESUMO

Drought and nitrogen enrichment could profoundly affect the productivity of semiarid ecosystems. However, how ecosystem productivity will respond to different drought scenarios, especially with a concurrent increase in nitrogen availability, is still poorly understood. Using data from a 4-year field experiment conducted in a semiarid temperate steppe, we explored the responses of aboveground net primary productivity (ANPP) to different drought scenarios and nitrogen addition, and the underlying mechanisms linking soil properties, plant species richness, functional diversity (community-weighted means of plant traits, functional dispersion) and phylogenetic diversity (net relatedness index) to ANPP. Our results showed that completely excluding precipitation in June (1-month intense drought) and reducing half the precipitation amount from June to August (season-long chronic drought) both significantly reduced ANPP, with the latter having a more negative impact on ANPP. However, reducing half of the precipitation frequency from June to August (precipitation redistribution) had no significant effect on ANPP. Nitrogen addition increased ANPP irrespective of drought scenarios. ANPP was primarily determined by soil moisture and nitrogen availability by regulating the community-weighted means of plant height, rather than other aspects of plant diversity. Our findings suggest that precipitation amount is more important than precipitation redistribution in influencing the productivity of temperate steppe, and nitrogen supply could alleviate the adverse impacts of drought on grassland productivity. Our study advances the mechanistic understanding of how the temperate grassland responds to drought stress, and implies that management strategies to protect tall species in the community would be beneficial for maintaining the productivity and carbon sequestration of grassland ecosystems under climate drought.

2.
Sci Total Environ ; 927: 172276, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583634

RESUMO

The increases in extent and frequency of extreme drought events and increased nitrogen (N) deposition due to global change are expected to have profound impacts on carbon cycling in semi-arid grasslands. However, how ecosystem CO2 exchange processes respond to different drought scenarios individually and interactively with N addition remains uncertain. In this study, we experimentally explored the effects of different drought scenarios (early season extreme drought, 50 % reduction in precipitation amount, and 50 % reduction in precipitation events) and N addition on net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), and gross ecosystem productivity (GEP) over three growing seasons (2019-2021) in a semi-arid grassland in northern China. The growing-season ecosystem carbon fluxes in response to drought and N addition were influenced by inter-annual precipitation changes, with 2019 as a normal precipitation year, and 2020 and 2021 as wet years. Early season extreme drought stimulated NEE by reducing ER. 50 % reduction in precipitation amount decreased ER and GEP consistently in three years, but only significantly suppressed NEE in 2019. 50 % reduction in precipitation events stimulated NEE. Nitrogen addition stimulated NEE, ER, and GEP, but only significantly in wet years. The structural equation models showed that changes in carbon fluxes were regulated by soil moisture, soil temperature, microbial biomass nitrogen (MBN), and the key plant functional traits. Decreased community-weighted means of specific leaf area (CWMSLA) was closely related to the reduced ER and GEP under early season extreme drought and 50 % reduction in precipitation amount. While increased community-weighted means of plant height (CWMPH) largely accounted for the stimulated ER and GEP under 50 % reduction in precipitation events. Our study stresses the distinct effects of different drought scenarios and N enrichment on carbon fluxes, and highlights the importance of soil traits and the key plant traits in determining carbon exchange in this water-limited ecosystem.


Assuntos
Ciclo do Carbono , Secas , Pradaria , Nitrogênio , Nitrogênio/análise , China , Chuva , Mudança Climática , Ecossistema , Carbono/metabolismo , Estações do Ano
3.
Sci Adv ; 10(16): eadl2063, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640232

RESUMO

All-perovskite tandem solar cells (TSCs) have exhibited higher efficiencies than single-junction perovskite solar cells (PSCs) but still suffer from the unsatisfactory performance of low-bandgap (LBG) tin-lead (Sn-Pb) subcells. The inherent properties of PEDOT:PSS are crucial to high-performance Sn-Pb perovskite films and devices; however, the underlying mechanism has not been fully explored and revealed. Here, we report a facile oxalic acid treatment of PEDOT:PSS (OA-PEDOT:PSS) to precisely regulate its work function and surface morphology. OA-PEDOT:PSS shows a larger work function and an ordered reorientation and fiber-shaped film morphology with efficient hole transport pathways, leading to the formation of more ideal hole-selective contact with Sn-Pb perovskite for suppressing interfacial nonradiative recombination losses. Moreover, OA-PEDOT:PSS induces (100) preferred orientation growth of perovskite for higher-quality Sn-Pb films. Last, the OA-PEDOT:PSS-tailored LBG PSC yields an impressive efficiency of up to 22.56% (certified 21.88%), enabling 27.81% efficient all-perovskite TSC with enhanced operational stability.

4.
Genes Genomics ; 46(4): 423-436, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38324226

RESUMO

BACKGROUND: Rubisco activase (RCA) is a pivotal enzyme that can catalyse the activation of Rubisco in carbon assimilation pathway. Many studies have shown that RCA may be a potential target for genetic manipulation aimed at enhancing photosynthetic efficiency and crop yield. OBJECTIVE: To understand the biological function of the GhRCAß2 gene in upland cotton, we cloned the coding sequence (CDS) of the GhRCAß2 gene and investigated its sequence features, evolutionary relationship, subcellular localization, promoter sequence and expression pattern. METHODS: The bioinformatics tools were used to analyze the sequence features of GhRCAß2 protein. Transient transformation of Arabidopsis mesophyll protoplasts was performed to determine the subcellular localization of the GhRCAß2 protein. The expression pattern of the GhRCAß2 gene was examined by analyzing transcriptome data and using the quantitative real-time PCR (qRT-PCR). RESULTS: The full-length CDS of GhRCAß2 was 1317 bp, and it encoded a protein with a chloroplast transit peptide. The GhRCAß2 had two conserved ATP-binding domains, and did not have the C-terminal extension (CTE) domain that was unique to the RCA α-isoform in plants. Evolutionarily, GhRCAß2 was clustered in Group A, and had a close evolutionary relationship with the soybean RCA. Western blot analysis demonstrated that GhRCAß2 was immunoreactive to the RCA antibody displaying a molecular weight similar to that of the RCA ß-isoform. The GhRCAß2 protein was found in chloroplast, aligning with its role as a vital enzyme in the process of photosynthesis. The GhRCAß2 gene had a leaf tissue-specific expression pattern, and the yellow-green leaf mutant exhibited a decreased expression of GhRCAß2 in comparison to the wild-type cotton plants. The GhRCAß2 promoter contained several cis-acting elements that respond to light, phytohormones and stress, suggesting that the expression of GhRCAß2 may be regulated by these factors. An additional examination of stress response indicated that GhRCAß2 expression was influenced by cold, heat, salt, and drought stress. Notably, diverse expression pattern was observed across different stress conditions. Additionally, low phosphorus and low potassium stress may result in a notable reduction in the expression of GhRCAß2 gene. CONCLUSION: Our findings will establish a basis for further understanding the function of the GhRCAß2 gene, as well as providing valuable genetic knowledge to improve cotton photosynthetic efficiency and yield under challenging environmental circumstances.


Assuntos
Arabidopsis , Gossypium , Gossypium/genética , Ribulose-Bifosfato Carboxilase/genética , Ribulose-Bifosfato Carboxilase/metabolismo , Ativador de Plasminogênio Tecidual , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Isoformas de Proteínas , Arabidopsis/metabolismo
5.
Res Aging ; 46(5-6): 275-286, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38189254

RESUMO

Consumer-directed Care (CDC) empowers older people to flexibly arrange services and enhances their well-being. Prior studies have suggested that limited attention and hassle costs are major demand-side barriers to using CDC. However, many other psychosocial factors were unexplored. In this study, we explore associations between CDC utilization and a wider range of psychosocial factors based on behavioral economics theories. A cross-sectional telephone survey of older persons (or family members that represent them) was conducted in Guangzhou, China in 2021. We adopted a two-stage sampling method based on administrative records and analyzed the data using multivariate logistic models. Procedural literacy, hassle costs, and social norms regarding CDC were associated with using CDC. The findings reveal nuances in the decision-making process, and people are not unboundedly rational in making care-related decisions. Policymakers could employ cost-effective tools to facilitate CDC utilization and optimize resources to address the most crucial service barriers.


Assuntos
Economia Comportamental , Humanos , Idoso , Feminino , Masculino , Estudos Transversais , China , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Inquéritos e Questionários , Tomada de Decisões
6.
ACS Chem Neurosci ; 15(3): 572-581, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38277219

RESUMO

Abnormal glutamate signaling is implicated in the heightened vulnerability of dopaminergic neurons in Parkinson's disease (PD). NMDA receptors are ion-gated glutamate receptors with high calcium permeability, and their GluN2D subunits are prominently distributed in the basal ganglia and brainstem nuclei. Previous studies have reported that dopamine depletion led to the dysfunctions of GluN2D-containing NMDA receptors in PD animal models. However, it remains unknown whether selective modulation of GluN2D could protect dopaminergic neurons against neurotoxicity in PD. In this study, we found that allosteric activation of GluN2D-containing NMDA receptors decreased the cell viability of MES23.5 dopaminergic cells and the GluN2D inhibitor, QNZ46, showed antioxidant effects and significantly relieved apoptosis in 6-OHDA-treated cells. Meanwhile, we demonstrated that QNZ46 might act via activation of the ERK/NRF2/HO-1 pathway. We also verified that QNZ46 could rescue abnormal behaviors and attenuate dopaminergic cell loss in a 6-OHDA-lesioned rat model of PD. Although the precise mechanisms underlying the efficacy of QNZ46 in vivo remain elusive, the inhibition of the GluN2D subunit should be a considerable way to treat PD. More GluN2D-selective drugs, which present minimal side effects and broad therapeutic windows, need to be developed for PD treatment in future studies.


Assuntos
Síndromes Neurotóxicas , Doença de Parkinson , Ratos , Animais , Oxidopamina/farmacologia , Neurônios Dopaminérgicos/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais
7.
Adv Mater ; 36(14): e2308969, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38145547

RESUMO

High efficiency and long-term stability are the prerequisites for the commercialization of perovskite solar cells (PSCs). However, inadequate and non-uniform doping of hole transport layers (HTLs) still limits the efficiency improvements, while the intrinsic instability of HTLs caused by ion migration and accumulation is difficult to be addressed by external encapsulation. Here it is shown that the addition of a conjugated phosphonic acid (CPA) to the Spiro-OMeTAD benchmark HTL can greatly enhance the device efficiency and intrinsic stability. Featuring an optimal diprotic-acid structure, indolo(3,2-b)carbazole-5,11-diylbis(butane-4,1-diyl) bis(phosphonic acid) (BCZ) is developed to promote morphological uniformity and mitigate ion migration across both perovskite/HTL and HTL/Ag interfaces, leading to superior charge conductivity, reinforced ion immobilization, and remarkable film stability. The dramatically improved interfacial charge collection endows BCZ-based n-i-p PSCs with a champion power conversion efficiency of 24.51%. More encouragingly, the BCZ-based devices demonstrate remarkable stability under harsh environmental conditions by retaining 90% of initial efficiency after 3000 h in air storage. This work paves the way for further developing robust organic HTLs for optoelectronic devices.

8.
J Aging Soc Policy ; : 1-21, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38151708

RESUMO

Consumer-directed care (CDC) programs for older people aim to optimize health outcomes by offering clients control and flexibility regarding service arrangements. However, policy design features may differ due to heterogenous sociostructural systems. By operationalizing a framework with three dimensions of CDC, i.e. control and direct services, variety of service options, and information and support, we analyzed how countries vary in their policy designs to achieve consumer direction. Using an expert survey (n = 20) and cross-national document analysis, we analyzed 12 CDC programs from seven selected countries: the United States, the United Kingdom, Germany, the Netherlands, China, Australia, and Spain. Among the three dimensions, CDC programs placed more emphasis on and displayed more homogenous performance of policy designs that achieve consumer direction in the dimension of control and direct services, while less emphasis was placed on and more heterogenous performance displayed in the dimensions of variety of service options and information and support. We offer a systematically operationalized framework to investigate CDC policy designs. Findings advance our understanding of CDC policy features from a cross-national perspective. Policymakers could incorporate these findings to empower older people in their respective societies.

9.
iScience ; 26(11): 108130, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37876795

RESUMO

Parkinson's disease (PD) is characterized by the irreversible loss of dopaminergic neurons and the accumulation of α-synuclein in Lewy bodies. The oligomeric α-synuclein (O-αS) is the most toxic form of α-synuclein species, and it has been reported to be a robust inflammatory mediator. Mutations in Leucine-Rich Repeat Kinase 2 (LRRK2) are also genetically linked to PD and neuroinflammation. However, how O-αS and LRRK2 interact in glial cells remains unclear. Here, we reported that LRRK2 G2019S mutation, which is one of the most frequent causes of familial PD, enhanced the effects of O-αS on astrocytes both in vivo and in vitro. Meanwhile, inhibition of LRRK2 kinase activity could relieve the inflammatory effects of both LRRK2 G2019S and O-αS. We also demonstrated that nuclear factor κB (NF-κB) pathway might be involved in the neuroinflammatory responses. These findings revealed that inhibition of LRRK2 kinase activity may be a viable strategy for suppressing neuroinflammation in PD.

10.
Mitochondrion ; 73: 10-18, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37708949

RESUMO

Mutations in the Leucine-rich repeat protein kinase 2 (LRRK2) gene are the most frequent cause of familial Parkinson's disease (PD). Although LRRK2 has been extensively studied, the pathogenic mechanism of the LRRK2 G2385R mutation, which is most common in Asian populations, especially in the Chinese Han population, remains unclear. In this study, we demonstrated that the LRRK2 G2385R mutation in HEK293T cells led to a reduction in cellular PGC-1α protein expression and inhibition of mitochondrial biogenesis through the PGC-1α-TFAM pathway. This resulted in a decrease in mitochondrial genome expression, which in turn impaired the normal electron transfer process of the oxidative phosphorylation respiratory chain, leading to mitochondrial dysfunction and onset of apoptosis. The mitochondrial dysfunction and apoptosis caused by the LRRK2 G2385R mutation were significantly alleviated by antioxidant Idebenone, which provides a theoretical basis for the subsequent development of precise treatment specifically for PD patients with LRRK2 G2385R mutation. Further validation of our findings in neurons and animal models are necessary.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Humanos , Proteínas de Ligação a DNA/genética , Células HEK293 , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Proteínas Mitocondriais/genética , Mutação , Biogênese de Organelas , Doença de Parkinson/genética , Fatores de Transcrição/genética , Mitocôndrias
11.
ACS Appl Mater Interfaces ; 15(34): 41109-41120, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37590128

RESUMO

Poly(3-hexylthiophene) (P3HT) represents a promising hole transport material for emerging perovskite solar cells (PSCs) due to its appealing merits of high thermal stability and appropriate hydrophobicity. Nonetheless, large energy losses at the P3HT/perovskite interface lead to unsatisfied efficiency and stability of the devices. Herein, two ionic dendritic molecules, 3,3'-(2,7-bis(3,6-bis(bis(4-methoxyphenyl)amino)-9H-carbazol-9-yl)-9H-fluorene-9,9-diyl)bis(N,N,N-trimethylpropan-1-aminium) iodide and 3,3'-(2,7-bis(bis(4-(bis(4-methoxyphenyl)amino)phenyl)amino)-9H-fluorene-9,9-diyl)bis(N,N,N-trimethylpropan-1-aminium) iodide, namely, MPA-Cz-FAI and MPA-PA-FAI, are rationally designed as the interlayer to enhance interfacial compatibility. The dendritic backbone with conjugated structure endows the hole transport layer with high conductivity, derived from the more ordered microstructure with larger crystallization and higher connectivity of domain zones. Besides, a better energy level alignment is established between P3HT and perovskite, which enhances the charge extraction and transport yield. In addition, the peripheral methoxy groups enable effective defect passivation at the interface to suppress nonradiative recombination and the quaternary ammonium iodide serving as side chains enable efficient interfacial hole extraction contributing to enhanced charge collection yield. As a result, the dopant-free P3HT-based PSCs modified with MPA-Cz-PAI deliver a champion efficiency of 19.7%, significantly higher than that of the control devices (15.4%). More encouragingly, the unencapsulated devices demonstrate competitive environmental stability by retaining over 85% of its initial efficiency after 1500 h of storage under humid conditions (70% relative humidity). This work provides an effective molecular design strategy for interface engineering, envisaging a bright prospect for the further development of efficient and stable perovskite solar cells.

12.
Acta Pharmacol Sin ; 44(12): 2418-2431, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37563446

RESUMO

Pain is a common annoying non-motor symptom in Parkinson's disease (PD) that causes distress to patients. Treatment for PD pain remains a big challenge, as its underlying mechanisms are elusive. Pituitary adenylate cyclase-activating polypeptide (PACAP) and its receptor PAC1-R play important roles in regulating a variety of pathophysiological processes. In this study, we investigated whether PACAP/PAC1-R signaling was involved in the mechanisms of PD pain. 6-hydroxydopamine (6-OHDA)-induced PD model was established in rats. Behavioral tests, electrophysiological and Western blotting analysis were conducted 3 weeks later. We found that 6-OHDA rats had significantly lower mechanical paw withdrawal 50% threshold in von Frey filament test and shorter tail flick latency, while mRNA levels of Pacap and Adcyap1r1 (gene encoding PAC1-R) in the spinal dorsal horn were significantly upregulated. Whole-cell recordings from coronal spinal cord slices at L4-L6 revealed that the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) in dorsal horn neurons was significantly increased, which was reversed by application of a PAC1-R antagonist PACAP 6-38 (250 nM). Furthermore, we demonstrated that intrathecal microinjection of PACAP 6-38 (0.125, 0.5, 2 µg) dose-dependently ameliorated the mechanical and thermal hyperalgesia in 6-OHDA rats. Inhibition of PACAP/PAC1-R signaling significantly suppressed the activation of Ca2+/calmodulin-dependent protein kinase II and extracellular signal-regulated kinase (ERK) in spinal dorsal horn of 6-OHDA rats. Microinjection of pAAV-Adcyap1r1 into L4-L6 spinal dorsal horn alleviated hyperalgesia in 6-OHDA rats. Intrathecal microinjection of ERK antagonist PD98059 (10 µg) significantly alleviated hyperalgesia in 6-OHDA rats associated with the inhibition of sEPSCs in dorsal horn neurons. In addition, we found that serum PACAP-38 concentration was significantly increased in PD patients with pain, and positively correlated with numerical rating scale score. In conclusion, activation of PACAP/PAC1-R induces the development of PD pain and targeting PACAP/PAC1-R is an alternative strategy for treating PD pain.


Assuntos
Doença de Parkinson , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Ratos , Humanos , Animais , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Oxidopamina , Doença de Parkinson/tratamento farmacológico , Transmissão Sináptica , Dor , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células do Corno Posterior/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo
13.
Adv Mater ; 35(35): e2303692, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37354138

RESUMO

Although hole transport layers (HTLs) based on solution-processed doped Spiro-OMeTAD are extremely popular and effective for their remarkable performance in n-i-p perovskite solar cells (PSCs), their scalable application is still being held back by poor chemical stability and unsatisfied scalability. Essentially, the volatile components and hygroscopic nature of ionic salts often cause morphological deformation that deteriorate both device efficiency and stability. Herein, a simple and effective molecular implantation-assisted sequential doping (MISD) approach is strategically introduced to modulate spatial doping uniformity of organic films and fabricate all evaporated Spiro-OMeTAD layer in which phase-segregation free HTL is achieved accompanied with high molecular density, uniform doping composition, and superior optoelectronic characteristics. The resultant MISD-based devices attain a record power conversion efficiency (PCE) of 23.4%, which represents the highest reported value among all the PSCs with evaporated HTLs. Simultaneously, the unencapsulated devices realize considerably enhanced stability by maintaining over 90% of their initial PCEs in the air for 5200 h and after working at maximum power point under illumination for 3000 h. This method provides a facile way to fabricate robust and reliable HTLs toward developing efficient and stable perovskite solar cells.

14.
Int J Mol Sci ; 24(7)2023 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-37047620

RESUMO

Sedoheptulose-1,7-bisphosphatase (SBPase, EC 3.1.3.37) is a key enzyme in the plant Calvin cycle and one of the main rate-limiting enzymes in the plant photosynthesis pathway. Many studies have demonstrated that the SBPase gene plays an important role in plant photosynthetic efficiency, yield, and stress responses; however, few studies have been conducted on the function and expression of the GhSBPase gene in upland cotton. In this study, our results showed that the coding sequence (CDS) of GhSBPase gene was 1182 bp, encoding a protein with 393 amino acids. The GhSBPase protein had adenosine monophosphate (AMP) binding site and a FIG (FBPase/IMPase/glpX) domain, and had six Cys residues and a CGGT(A/Q)C motif that were involved in redox regulation in plants. Evolutionarily, the GhSBPase protein clustered into the dicotyledon subgroup and was most closely related to the tomato SlSBPase protein. Western-blot analysis further indicated that the GhSBPase gene was indeed the gene encoding the SBPase protein in upland cotton. The GhSBPase protein was localized in chloroplast, which was consistent with its function as a key enzyme in photosynthesis. The GhSBPase gene was specifically highly expressed in leaves, and its expression level was significantly lower in a yellow-green leaf mutant than in the wild type. Moreover, the GhSBPase expression was in response to drought, salt, high- and low-temperature stress, and exhibits different expression patterns. The GhSBPase promoter had the cis-acting elements in response to abiotic stress, phytohormone, and light. In addition, the GhSBPase expression was positively correlated with the chlorophyll fluorescence parameters, suggesting that changes in the expression of the GhSBPase had potential applicability in breeding for enhanced cotton photosynthetic efficiency. These results will help to understand the function of the GhSBPase gene in photosynthesis and the adaptability of plants to external stress and provide important gene information for the high-yield breeding of crops in the future.


Assuntos
Gossypium , Melhoramento Vegetal , Gossypium/genética , Gossypium/metabolismo , Fotossíntese/genética , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Regulação da Expressão Gênica de Plantas
15.
Adv Mater ; 35(28): e2300233, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37021877

RESUMO

The perovskite buried interfaces have demonstrated pivotal roles in determining both the efficiency and stability of perovskite solar cells (PSCs); however, challenges remain in understanding and managing the interfaces due to their non-exposed feature. Here, we proposed a versatile strategy of pre-grafted halides to strengthen the SnO2 -perovskite buried interface by precisely manipulating perovskite defects and carrier dynamics through alteration of halide electronegativity (χ), thereby resulting in both favorable perovskite crystallization and minimized interfacial carrier losses. Specifically, the implementation of fluoride with the highest χ induces the strongest binding affinity to uncoordinated SnO2  defects and perovskite cations, leading to retarded perovskite crystallization and high-quality perovskite films with reduced residual stress. These improved properties enable champion efficiencies of 24.2% (the control: 20.5%) and 22.1% (the control: 18.7%) in rigid and flexible devices with extremely low voltage deficit down to 386 mV, all of which are among the highest reported values for PSCs with a similar device architecture. In addition, the resulting devices exhibit marked improvements in the device longevity under various stressors of humidity (>5000 h), light (1000 h), heat (180 h), and bending test (10 000 times). This method provides an effective way to improve the quality of buried interfaces toward high-performance PSCs.


Assuntos
Compostos de Cálcio , Compostos Inorgânicos , Óxidos , Cristalização
16.
ACS Appl Mater Interfaces ; 15(17): 21252-21260, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37073888

RESUMO

Interfaces between functional layers in perovskite solar cells (PSCs) are of paramount importance in determining their efficiency and stability, but the interaction and stability of metal-hole conductor (HC) interfaces have received less attention. Here, we discover an intriguing transient behavior in devices which induces a profound efficiency fluctuation from 9 to 20% during the initial performance testing. Air exposure (e.g., oxygen and moisture) can significantly accelerate this nonequilibrium process and simultaneously enhance the device maximal efficiency. Structural analysis reveals that the chemical reaction between Ag and HC occurred during the metal deposition by thermal evaporation, leading to the formation of an insulating barrier layer at their interfaces, which results in a high charge-transport barrier and poor device performance. Accordingly, we propose a metal diffusion-associated barrier evolution mechanism to understand the metal/HC interfaces. To mitigate these detrimental effects, we strategically develop an interlayer strategy by introducing an ultrathin layer of molybdenum oxide (MoO3) between Ag and HC, which is found to effectively suppress the interfacial reaction, yielding highly reliable PSCs with instant high efficiency. This work provides new insights into understanding the metal-organic interfaces, and the developed interlayer strategy can be generally applicable to engineer other interfaces in realizing efficient and stable contacts.

17.
Mater Horiz ; 10(7): 2609-2617, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37097145

RESUMO

The bottom hole transport layers (HTLs) are of paramount importance in determining both the efficiency and stability of inverted perovskite solar cells (PSCs), however, their surface nature and properties strongly interfere with the upper perovskite crystallization kinetics and also influence interfacial carrier dynamics. In this work, we strategically develop a simple, facile and spontaneous fabrication method of the HTL at the perovskite/electrode interface by dynamic self-assembly (DSA) of small molecules during perovskite crystallization. Different from the traditional layer-by-layer approach, this DSA strategy involves a bilateral movement of self-assembled molecules (SAMs) from perovskite solution, realizing simultaneous fabrication of the HTL and perovskite surface passivation. We design a multifunctional molecule, (4-(7H-benzo[c]carbazol-7-yl)butyl)phosphonic acid (BCB-C4PA), for the DSA process, to optimize both self-assembly ability and interfacial energy alignment. Benefitting from this unconventional DSA approach and BCB-C4PA, a champion PCE of 22.2% is achieved along with remarkable long-term environmental stability for over 2750 h, which is among the highest reported efficiencies for SAM-based PSCs. This investigation provides a creative, unique and effective molecular approach for preparing reliable charge transport layers, opening up new avenues for the further development of efficient interfacial contacts for PSCs.

18.
Heart Surg Forum ; 26(1): E020-E026, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36856501

RESUMO

OBJECTIVES: Cardiopulmonary bypass (CPB) induces inflammatory homeostasis dysregulation, closely related to many postoperative adverse effects. Minimizing the systemic inflammatory response to CPB is imperative to improving cardiac surgery safety. This study aimed to retrospectively evaluate the efficacy of the hemoperfusion cartridge, a device recently designed for extracorporeal blood purification to remove cytokines from the blood for patients undergoing cardiac valve replacement surgery using CPB. METHODS: The hemoperfusion (HP) group consisted of 138 patients, who underwent a hemoperfusion cartridge procedure during CPB. The control group included 149 patients, who received standard CPB management. The evaluated indices included inflammatory cytokines, blood biochemical indices, and postoperative outcome indices. RESULTS: Patients in the HP group had relatively lower interleukin (IL)-6 levels (days one and two post-CPB) and IL-8 (day one post-CPB) compared with the control group. Some relatively decreased biochemical blood indices also were observed in the HP group, including a significantly lower lactic acid level (days one, two, and three post-CPB), platelet counts (days one, two, and three post-CPB), and aspartate aminotransferase (days one and three post-CPB). Regarding the postoperative outcomes, no severe complications occurred in the patients; however, the HP group required less ventilation time than the control group. CONCLUSIONS: The hemoperfusion cartridge seems promising in limiting the inflammatory reactions during CPB, with noteworthy potential for application in cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Hemoperfusão , Humanos , Ponte Cardiopulmonar , Estudos Retrospectivos , Citocinas , Interleucina-6 , Valvas Cardíacas
19.
Front Cardiovasc Med ; 10: 1037357, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970344

RESUMO

Pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) is a severely progressive condition with uncertain physiological course. Hence, it has become increasingly relevant to clarify the specific mechanisms of molecular modification, which is crucial to identify more treatment strategies. With the rapid development of high-throughput sequencing, omics technology gives access to massive experimental data and advanced techniques for systems biology, permitting comprehensive assessment of disease occurrence and progression. In recent years, significant progress has been made in the study of PAH-CHD and omics. To provide a comprehensive description and promote further in-depth investigation of PAH-CHD, this review attempts to summarize the latest developments in genomics, transcriptomics, epigenomics, proteomics, metabolomics, and multi-omics integration.

20.
Yonsei Med J ; 64(4): 259-268, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36996897

RESUMO

PURPOSE: We aimed to analyze the optimal timing of enteral nutrition (EN) in the treatment of sepsis and its effect on sepsis-associated acute kidney injury (SA-AKI.). MATERIALS AND METHODS: The MIMIC-III database was employed to identify patients with sepsis who had received EN. With AKI as the primary outcome variable, receiver operating characteristic (ROC) curves were utilized to calculate the optimal cut-off time of early EN (EEN). Propensity score matching (PSM) was employed to control confounding effects. Logistic regressions and propensity score-based inverse probability of treatment weighting were utilized to assess the robustness of our findings. Comparisons within the EEN group were performed. RESULTS: 2364 patients were included in our study. With 53 hours after intensive care units (ICU) admission as the cut-off time of EEN according to the ROC curve, 1212 patients were assigned to the EEN group and the other 1152 to the delayed EN group. The risk of SA-AKI was reduced in the EEN group (odds ratio 0.319, 95% confidence interval 0.245-0.413, p<0.001). The EEN patients received fewer volumes (mL) of intravenous fluid (IVF) during their ICU stay (3750 mL vs. 5513.23 mL, p<0.001). The mediating effect of IVF was significant (p<0.001 for the average causal mediation effect). No significant differences were found within the EEN group (0-48 hours vs. 48-53 hours), except that patients initiating EN within 48 hours spent fewer days in ICU and hospital. CONCLUSION: EEN is associated with decreased risk of SA-AKI, and this beneficial effect may be proportionally mediated by IVF volume.


Assuntos
Injúria Renal Aguda , Sepse , Humanos , Estudos de Coortes , Nutrição Enteral/efeitos adversos , Pontuação de Propensão , Unidades de Terapia Intensiva , Sepse/complicações , Injúria Renal Aguda/terapia , Estudos Retrospectivos
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