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1.
Nano Lett ; 23(5): 1938-1945, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36802631

RESUMO

Symmetry-broken-induced spin splitting plays a key role for selective circularly polarized light absorption and spin carrier transport. Asymmetrical chiral perovskite is rising as the most promising material for direct semiconductor-based circularly polarized light detection. However, the increase of asymmetry factor and extension of response region remain to be a challenge. Herein, we fabricated a two-dimensional tin-lead mixed chiral perovskite with tunable absorption in the visible region. Theoretical simulation indicates that the mixing of the tin and lead in chiral perovskite breaks the symmetry of the pure ones, resulting in pure spin splitting. We then fabricated a chiral circularly polarized light detector based on this tin-lead mixed perovskite. A high asymmetry factor for the photocurrent of 0.44 is achieved, which is 144% higher than pure lead 2D perovskite, and it is the highest value reported for the pure chiral 2D perovskite-based circularly polarized light detector using a simple device structure.

2.
Chemistry ; 29(14): e202202930, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36484147

RESUMO

Recently, extensive efforts have been devoted to the development of the second near-infrared bio-window (NIR-II, 1000-1700 nm) theranostic agents owing to the excellent tissue-penetration capability of NIR-II light. The exploration of organic NIR-II photothermal therapy materials, especially those with absorption peak over 1000 nm, is an appealing yet significantly challenging task. Herein, we have designed conjugated polymer nanoparticles (PIS NPs) with NIR-II absorption peak at 1026 nm through a combined strategy of introducing quinoid donor-acceptor (D-A) structures, constructing intramolecular "conformational locks" and extending the conjugation area to narrow the band gap. Irradiated at 1064 nm, PIS NPs showed remarkable photothermal conversion performance for efficient photothermal ablation of tumor cells in vitro and in vivo. This study provides useful insights into the rational design of organic NIR-II photothermal agents based on multiple strategies.


Assuntos
Nanopartículas , Terapia Fototérmica , Polímeros/química , Nanopartículas/química , Fenômenos Químicos , Fototerapia , Nanomedicina Teranóstica
3.
Angew Chem Int Ed Engl ; 61(20): e202202346, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35233881

RESUMO

The combination of comprehensive surface passivation and effective interface carriers transfer plays a critical role in high-performance perovskite solar cells. A 2D structure is an important approach for surface passivation of perovskite film, however, its large band gap could compromise carrier transfer. Herein, we synthesize a new molecule 2-thiopheneethylamine thiocyanate (TEASCN) for the construction of bilayer quasi-2D structure precisely on a tin-lead mixed perovskite surface. This bilayer structure can passivate the perovskite surface and ensure effective carriers transfer simultaneously. As a result, the open-circuit voltage (Voc ) of the device is increased without sacrificing short-circuit current density (Jsc ), giving rise to a high certified efficiency from a credible third-party certification of narrow band gap perovskite solar cells. Furthermore, theoretical simulation indicates that the inclusion of TEASCN makes the bilayer structure thermodynamically more stable, which provides a strategy to tailor the number of layers of quasi-2D perovskite structures.

4.
Invest New Drugs ; 39(4): 1089-1098, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686452

RESUMO

Notch signaling plays an important role in development and tissue homeostasis. Deregulation of Notch signaling has been implicated in multiple malignancies. Crenigacestat (LY3039478), a potent Notch inhibitor, decreases Notch signaling and its downstream biologic effects. I6F-MC-JJCD was a multicenter, nonrandomized, open-label, Phase 1b study with 5 separate, parallel dose-escalations in patients with advanced or metastatic cancer from a variety of solid tumors, followed by a dose-confirmation phase in prespecified tumor types. This manuscript reports on 3 of 5 groups. The primary objective was to determine the recommended Phase 2 dose of crenigacestat in combination with other anticancer agents (taladegib, LY3023414 [dual inhibitor of phosphoinositide 3-kinase; mechanistic target of rapamycin], or abemaciclib). Secondary objectives included evaluation of safety, tolerability, efficacy, and pharmacokinetics. Patients (N = 63) received treatment between November 2016 and July 2019. Dose-limiting toxicities occurred in 12 patients, mostly gastrointestinal (diarrhea, nausea, vomiting). The maximum-tolerated dose of crenigacestat was 25 mg in Part B (LY3023414), 50 mg in Part C (abemaciclib), and not established in Part A (taladegib) due to toxicities. Patients had at least 1 adverse event (AE) and 75.0-82.6% were ≥ Grade 3 all-causality AEs. No patient had complete or partial response. Disease control rates were 18.8% (Part B) and 26.1% (Part C). The study was terminated before dose confirmation cohorts were triggered. This study demonstrated that crenigacestat combined with different anticancer agents (taladegib, LY3023414, or abemaciclib) was poorly tolerated, leading to lowered dosing and disappointing clinical activity in patients with advanced or metastatic solid tumors. NCT02784795 and date of registration: May 27, 2016.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias/tratamento farmacológico , Aminopiridinas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzazepinas/administração & dosagem , Benzimidazóis/administração & dosagem , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neoplasias/patologia , Ftalazinas/administração & dosagem , Piridinas/administração & dosagem , Quinolonas/administração & dosagem
5.
Invest New Drugs ; 39(4): 1057-1071, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33624233

RESUMO

Background Tumor-associated macrophages (TAMs) promote tumor growth, metastasis, and therapeutic resistance via colony-stimulating factor-1 (CSF-1), acting through CSF-1 receptor (CSF-1R) signaling. This phase 1 study determined the safety, tolerability, pharmacokinetics-pharmacodynamics, immunogenicity, and efficacy of the anti-CSF-1R antibody LY3022855 in solid tumors. Methods Patients with advanced solid tumors refractory to standard therapy were enrolled and treated in 2 dosing cohorts: weight-based (part A) and non-weight-based (part B). Part A patients were assigned to intravenous (IV) dose-escalation cohorts: 2.5 mg/kg once per week (QW), 0.3 mg/kg QW, 0.6 mg/kg QW, 1.25 mg/kg once every 2 weeks (Q2W) and 1.25 mg/kg QW doses of LY3022855. Non-weight-based doses in part B were 100 mg and 150 mg IV QW. Results Fifty-two patients (mean age 58.6 ± 10.4 years) were treated with ≥1 dose of LY3022855 (range: 4-6). Five dose-limiting toxicities (left ventricular dysfunction, anemia, pancreatitis, rhabdomyolysis, and acute kidney injury) occurred in 4 patients. The non-weight-based 100 mg QW dose was established as the RP2D. The most common treatment-emergent adverse events were increase in liver function variables, fatigue, nausea, vomiting, diarrhea, anorexia, pyrexia, increased lipase, amylase, and lactate dehydrogenase. Clearance decreased with increasing dose and weight-based dosing had minimal effect on pharmacokinetics. Serum CSF-1, and IL-34 levels increased at higher doses and more frequent dosing, whereas TAMs and CD14dimCD16bright levels decreased. Three patients achieved stable disease. No responses were seen. Conclusions LY3022855 was well tolerated and showed dose-dependent pharmacokinetics-pharmacodynamics and limited clinical activity in a heterogenous solid tumor population. ClinicalTrials.gov ID NCT01346358 (Registration Date: May 3, 2011).


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Piridinas/uso terapêutico , Administração Intravenosa , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/efeitos adversos , Piridinas/farmacocinética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Adulto Jovem
6.
Mol Pharm ; 17(12): 4443-4462, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-32926628

RESUMO

As a BCS IV drug, ursolic acid (UA) has low oral bioavailability mainly because of its poor aqueous solubility/dissolution, poor permeability, and metabolism by cytochrome P450 (CYP) isozymes, such as CYP3A4. Most UA preparations demonstrated a much higher dissolution than that of its crystalline form yet a low drug concentration in plasma due to their lower consideration or evaluation for the permeability and metabolism issues. In the current study, a supramolecular coamorphous system of UA with piperine (PIP) was prepared and characterized by powder X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy. In comparison to crystalline UA and UA in physical mixture, such coamorphous system enhanced solubility (5.3-7-fold in the physiological solution) and dissolution (7-8-fold in the physiological solution within 2 h) of UA and exhibited excellent physical stability under 90-day storage conditions. More importantly, the pharmacokinetic study of coamorphous UA in rats exhibited 5.8-fold and 2.47-fold improvement in AUC0-∞ value, respectively, compared with its free and mixed crystalline counterparts. In order to further explore the mechanism of such improvement, the molecular interactions of a coamorphous system in the solid state were investigated. Fourier transform infrared spectroscopy, solid-state 13C nuclear magnetic resonance spectroscopy, and density functional theory modeling suggested that intermolecular hydrogen bonds with strong interactions newly formed between UA and PIP after coamorphization. The in vitro permeability studies across Caco-2 cell monolayer and metabolism studies by rat hepatic microsomes indicated that free PIP significantly increased the permeability of UA and inhibited the enzymatic metabolism of UA by CYP3A4. However, PIP in the coamorphous combination exhibited a much lower level in the bioenhancing than its free form arising from the synchronized dissolution characteristic of the preparation (only 60% of PIP released in comparison to its free counterpart in 2 h). The in situ loop study in rats proposed that the acid-sensitive dissolution in the stomach of the coamorphous preparation helped to improve the effective free drug concentration, thereby facilitating PIP to play its role in bioenhancing. The current study offers an exploratory strategy to overcome poor solubility/dissolution, poor permeability, and metabolism by cytochrome P450 isozymes of the BCS IV drug to improve its oral bioavailability.


Assuntos
Alcaloides/farmacocinética , Benzodioxóis/farmacocinética , Inibidores do Citocromo P-450 CYP3A/farmacocinética , Citocromo P-450 CYP3A/metabolismo , Piperidinas/farmacocinética , Alcamidas Poli-Insaturadas/farmacocinética , Triterpenos/farmacocinética , Administração Oral , Alcaloides/administração & dosagem , Alcaloides/química , Animais , Benzodioxóis/administração & dosagem , Benzodioxóis/química , Disponibilidade Biológica , Células CACO-2 , Inibidores do Citocromo P-450 CYP3A/administração & dosagem , Inibidores do Citocromo P-450 CYP3A/química , Combinação de Medicamentos , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Microssomos Hepáticos , Permeabilidade , Piperidinas/administração & dosagem , Piperidinas/química , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/química , Ratos , Solubilidade , Triterpenos/administração & dosagem , Triterpenos/química , Ácido Ursólico
7.
Small ; 13(26)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28544445

RESUMO

1D hollow nanostructures combine the advantages of enhanced surface-to-volume ratio, short transport lengths, and efficient 1D electron transport, which can provide more design ideas for the preparation of highly active oxygen evolution (OER) electrocatalysts. A unique architecture of dual-phase octahedral CoMn2 O4 /carbon hollow nanofibers has been prepared via a two-step heat-treatment process including preoxidation treatment and Ostwald ripening process. The hollow and porous structures provide interior void spaces, large exposed surfaces, and high contact areas between the nanofibers and electrolyte and the morphology can be engineered by adjusting the heating conditions. Due to the intimate electrical and chemical coupling between the oxide nanocrystals and integrated carbon, the dual-phase octahedral CoMn2 O4 /carbon hollow nanofibers exhibit excellent OER activity with overpotentials of 337 mV at current density of 10 mA cm-2 and Tafel slope of 82 mV dec-1 . This approach will lead to the new perception of design issue for the nanoarchitecture with fine morphology, structures, and excellent electrocatalytic activity.

8.
Chemistry ; 23(48): 11513-11518, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28707378

RESUMO

A thin layer of a highly porous metal-organic framework material, ZIF-8, is fabricated uniformly on the surface of nanostructured transition metal oxides (ZnO nanoflakes and MnO2 nanorods) to boost the transfer of lithium ions. The novel design and uniform microstructure of the MOF-coated TMOs (ZIF-8@TMOs) exhibit dramatically enhanced rate and cycling performance comparing to their pristine counterparts. The capacities of ZIF-8@ZnO (nanoflakes) and ZIF-8@MnO2 (nanorods) are 28 % and 31 % higher that of the pristine ones at the same current density. The nanorods of ZIF-8@MnO2 show a capacity of 1067 mAh g-1 after 500 cycles at 1 Ag-1 and without any fading. To further improve the conductivity and capacity, the ZIF-8-coated materials are pyrolyzed at 700 °C in an N2 atmosphere (ZIF-8@TMO-700 N). After pyrolysis, a much higher capacity improvement is achieved: ZIF-8@ZnO-700 N and ZIF-8@MnO2 -700 N have 54 % and 69 % capacity increases compared with the pristine TMOs, and at 1 Ag-1 , the capacity of ZIF-8@MnO2 -700 N is 1060 mAh g-1 after cycling for 300 cycles.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2198-202, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26672293

RESUMO

For researching the community structure, composition, and distribution of the planktonic algae in the Three Gorges Reservoir (TRG), especially, within TRG water levels' fluctuating, mpacting to water quality with the algae's growing, 6 sampling cites in the end of the TGR's back water zone, from Chaotianmen to Taihonggang Town, are chosen to monitor, at the sensitive stages time of algal bloom between March to May 2012, namely, water levels lowing from the highest impounding. The community's structure, composition, and distribution of the planktonic algae in the TGR, and the correlation of water quality parameters and DOM's fluorescence features with algae density, are obtained. According to the experimental results, blue algae fibre, chlorella, melosira, navicula are the dominated algae in the end of the TGR's back water zone, from Chaotianmen to Taihonggang Town, algae density are 0.40~0.56 × 10(6), 1.9~0.8 × 10(6), 0.36~0.25 × 10(6), 0.42~0.15 × 10(6) cells · L(-1) respectively. Besides, anabaena, phormidium, cladophora, feather, ovate algae are existing in only limited 2 sections. The fitting results reveal obvious linear correlation of the EEM characteristics of DOM with the 4 kinds of dominated algal density, which could be useful conference for the algae bloom monitor, conveniently and effectively.


Assuntos
Fluorescência , Compostos Orgânicos/análise , Fitoplâncton , Água/química , China , Diatomáceas , Meio Ambiente , Eutrofização , Rios , Qualidade da Água
10.
Bioinformatics ; 29(10): 1275-82, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23589650

RESUMO

MOTIVATION: RNA-seq experiments produce digital counts of reads that are affected by both biological and technical variation. To distinguish the systematic changes in expression between conditions from noise, the counts are frequently modeled by the Negative Binomial distribution. However, in experiments with small sample size, the per-gene estimates of the dispersion parameter are unreliable. METHOD: We propose a simple and effective approach for estimating the dispersions. First, we obtain the initial estimates for each gene using the method of moments. Second, the estimates are regularized, i.e. shrunk towards a common value that minimizes the average squared difference between the initial estimates and the shrinkage estimates. The approach does not require extra modeling assumptions, is easy to compute and is compatible with the exact test of differential expression. RESULTS: We evaluated the proposed approach using 10 simulated and experimental datasets and compared its performance with that of currently popular packages edgeR, DESeq, baySeq, BBSeq and SAMseq. For these datasets, sSeq performed favorably for experiments with small sample size in sensitivity, specificity and computational time. AVAILABILITY: http://www.stat.purdue.edu/∼ovitek/Software.html and Bioconductor. CONTACT: ovitek@purdue.edu SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Modelos Estatísticos , Análise de Sequência de RNA/métodos , Distribuição Binomial , Probabilidade , RNA/genética , Tamanho da Amostra , Transcriptoma
11.
Natl Sci Rev ; 11(5): nwae055, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38577668

RESUMO

Enhancing the quality of junctions is crucial for optimizing carrier extraction and suppressing recombination in semiconductor devices. In recent years, metal halide perovskite has emerged as the most promising next-generation material for optoelectronic devices. However, the construction of high-quality perovskite junctions, as well as characterization and understanding of their carrier polarity and density, remains a challenge. In this study, using combined electrical and spectroscopic characterization techniques, we investigate the doping characteristics of perovskite films by remote molecules, which is corroborated by our theoretical simulations indicating Schottky defects consisting of double ions as effective charge dopants. Through a post-treatment process involving a combination of biammonium and monoammonium molecules, we create a surface layer of n-type low-dimensional perovskite. This surface layer forms a heterojunction with the underlying 3D perovskite film, resulting in a favorable doping profile that enhances carrier extraction. The fabricated device exhibits an outstanding open-circuit voltage (VOC) up to 1.34 V and achieves a certified efficiency of 19.31% for single-junction wide-bandgap (1.77 eV) perovskite solar cells, together with significantly enhanced operational stability, thanks to the improved separation of carriers. Furthermore, we demonstrate the potential of this wide-bandgap device by achieving a certified efficiency of 27.04% and a VOC of 2.12 V in a perovskite/perovskite tandem solar cell configuration.

12.
Stat Med ; 32(9): 1509-23, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23023654

RESUMO

Medical cost data are typically highly skewed to the right with a large proportion of zero costs. It is also common for these data to be censored because of incomplete follow-up and death. In the case of censoring due to death, it is important to consider the potential dependence between cost and survival. This association can occur because patients who incur a greater amount of medical cost tend to be frailer and hence are more likely to die. To handle this informative censoring issue, joint modeling of cost and survival with shared random effects has been proposed. In this paper, we extend this joint modeling approach to handle a final feature of many medical cost data sets, i.e., Specifically, the fact that data were obtained via a complex survey design. Specifically, we extend the joint model by incorporating the sample weights when estimating the parameters and using the Taylor series linearization approach when calculating the standard errors. We use a simulation study to compare the joint modeling approach with and without these adjustments. The simulation study shows that parameter estimates can be seriously biased when information about the complex survey design is ignored. It also shows that standard errors based on the Taylor series linearization approach provide satisfactory confidence interval coverage. The proposed joint model is applied to monthly hospital costs obtained from the 2004 National Long Term Care Survey.


Assuntos
Modelos Econômicos , Modelos Estatísticos , Análise de Sobrevida , Idoso , Idoso de 80 Anos ou mais , Simulação por Computador , Intervalos de Confiança , Humanos , Assistência de Longa Duração/economia
13.
PLoS Genet ; 6(11): e1001193, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-21085628

RESUMO

The genetic model plant Arabidopsis thaliana, like many plant species, experiences a range of edaphic conditions across its natural habitat. Such heterogeneity may drive local adaptation, though the molecular genetic basis remains elusive. Here, we describe a study in which we used genome-wide association mapping, genetic complementation, and gene expression studies to identify cis-regulatory expression level polymorphisms at the AtHKT1;1 locus, encoding a known sodium (Na(+)) transporter, as being a major factor controlling natural variation in leaf Na(+) accumulation capacity across the global A. thaliana population. A weak allele of AtHKT1;1 that drives elevated leaf Na(+) in this population has been previously linked to elevated salinity tolerance. Inspection of the geographical distribution of this allele revealed its significant enrichment in populations associated with the coast and saline soils in Europe. The fixation of this weak AtHKT1;1 allele in these populations is genetic evidence supporting local adaptation to these potentially saline impacted environments.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Ecossistema , Variação Genética , Água do Mar , Sódio/metabolismo , Simportadores/genética , Simportadores/metabolismo , Alelos , Arabidopsis/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Geografia , Folhas de Planta/genética , Folhas de Planta/metabolismo
14.
Environ Sci Pollut Res Int ; 30(35): 83558-83574, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37341941

RESUMO

Over the past decade, financial development has been a prominent debate for stakeholders and policymakers alike. Financial development are prerequisites for innovation and CO2 emissions, followed by the Paris Climate Summit (COP21). In the wake of the global economic recession, financial development continues to address CO2 emissions efforts. However, scant attention is paid to the role of financial development in innovation and CO2 emissions relationship, especially in the context of developing countries. The current study explores the relationship between innovation and CO2 emissions through moderating role of financial development, especially in the context of developing countries. Utilizing a dynamic panel threshold approach, the current study utilizes data from 26 countries between 1990 and 2014. Our findings reveal that innovation positively impacts the reduction of carbon emissions when the stock market value-to-private credit ratio is below 1.71, while an opposite effect is observed when the ratio exceeds this threshold. We believe that the findings broaden the debate on financial development in developing countries. The results revealed that developing countries should allocate their domestic resources to financial development and poverty reduction, rather than solely addressing environmental concerns. In addition, a more sustainable balance between innovation and CO2 emissions could benefit through financial development and the impact may be the result in terms of achieving sustainable development.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Carbono , Clima
15.
PLoS One ; 18(12): e0296007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38100486

RESUMO

The spillover effect of university-based agricultural research and development (R&D) has been recognized as a crucial factor contributing to the enhanced performance of the agricultural industry. Nonetheless, the psychological impact of organizational inertia on individuals and groups may shape the influence of such spillovers for agribusiness firms. To date, there has been limited exploration of the interplay between university agricultural R&D spillovers and agribusiness firms. Utilizing panel data from Chinese listed agribusiness firms between 2009 and 2019, our empirical investigation reveals a negative short-term relationship between university agricultural R&D spillovers and agribusiness firm performance due to the similarity in knowledge backgrounds. In the short term, organizational inertia, stemming from familiar and parallel knowledge, renders university agricultural R&D spillovers unfavorable to agribusiness firm performance, thereby reducing their value to the enterprises. Conversely, the long-term influence of university agricultural R&D spillovers on agricultural enterprise performance is positive, as organizational inertia dissipates over time. Additionally, our findings indicate that university non-agricultural R&D spillovers serve to positively moderate the relationship between agricultural R&D spillovers and agribusiness firm performance in the short term, while exerting a negative moderating effect in the long term. Lastly, our analysis reveals a negative correlation between the effect of university agricultural R&D spillovers and the geographical distance between agribusiness firms and universities. This suggests that proximity to academic institutions may play a role in shaping the impact of R&D spillovers on agribusiness performance. In summary, our study highlights the complex dynamics between university agricultural R&D spillovers and agribusiness firm performance, revealing both short-term and long-term effects. We also underscore the importance of considering the influence of organizational inertia and the moderating role of non-agricultural R&D spillovers. Understanding these relationships is crucial for informing strategic decisions and fostering innovation within the agricultural industry.


Assuntos
Agricultura , Indústrias , Humanos , Universidades , Criatividade , China
16.
Life Sci ; 328: 121902, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392777

RESUMO

AIMS: The small GTPase protein ARF1 has been shown to be involved in the lipolysis pathway and to selectively kill stem cells in Drosophila melanogaster. However, the role of ARF1 in mammalian intestinal homeostasis remains elusive. This study aimed to explore the role of ARF1 in intestinal epithelial cells (IECs) and reveal the possible mechanism. MATERIALS AND METHODS: IEC-specific ARF1 deletion mouse model was used to evaluate the role of ARF1 in intestine. Immunohistochemistry and immunofluorescence analyses were performed to detect specific cell type markers, and intestinal organoids were cultured to assess intestinal stem cell (ISC) proliferation and differentiation. Fluorescence in situ hybridization, 16S rRNA-seq analysis, and antibiotic treatments were conducted to elucidate the role of gut microbes in ARF1-mediated intestinal function and the underlying mechanism. Colitis was induced in control and ARF1-deficient mice by dextran sulfate sodium (DSS). RNA-seq was performed to elucidate the transcriptomic changes after ARF1 deletion. KEY FINDINGS: ARF1 was essential for ISC proliferation and differentiation. Loss of ARF1 increased susceptibility to DSS-induced colitis and gut microbial dysbiosis. Gut microbiota depletion by antibiotics could rescue the intestinal abnormalities to a certain extent. Furthermore, RNA-seq analysis revealed alterations in multiple metabolic pathways. SIGNIFICANCE: This work is the first to elucidate the essential role of ARF1 in regulating gut homeostasis, and provides novel insights into the pathogenesis of intestinal diseases and potential therapeutic targets.


Assuntos
Fator 1 de Ribosilação do ADP , Células-Tronco Adultas , Microbioma Gastrointestinal , Intestino Delgado , Animais , Camundongos , Camundongos Knockout , Intestino Delgado/citologia , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Fator 1 de Ribosilação do ADP/metabolismo , Células-Tronco Adultas/metabolismo , Disbiose/metabolismo , Antibacterianos/administração & dosagem , Transcrição Gênica , Homeostase , Redes e Vias Metabólicas
17.
Heliyon ; 9(10): e20974, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876450

RESUMO

Amid heightened inter-company competition and the global drive towards ESG reforms, this study investigates whether enhancing the ESG performance of listed companies in China assists in elevating their reputation. It also examines the mediating role of investor attention in the relationship between ESG performance and company reputation, and further delves into whether there's a threshold effect of investor attention on the ESG-performance relationship. Utilizing sample data from Chinese listed companies spanning 2011 to 2021, and employing methods such as the panel two-way fixed-effects regression model, mediation effect testing, and threshold effect models, the study reveals that there is a significant positive relationship between ESG performance and the reputation of these companies. Moreover, a unique threshold effect is observed in the relationship between ESG performance and reputation. Innovatively, our research confirms the mediating role of investor attention in the relationship between ESG performance and company reputation, noting a more pronounced mediation effect in non-state-owned companies as opposed to state-owned ones. This study builds upon the existing literature on the relationship between CSR and company reputation, as well as between investor attention and reputation. By elucidating the mediating role of investor attention and its dual threshold effect, we provide a nuanced perspective on how ESG performance influences company reputation. Practically speaking, this research offers strategic recommendations for companies, investors, and regulators in the Chinese market on reputation management aligned with ESG principles. For instance, companies should prioritize their ESG performance, striving to maintain it above the market average, thus optimizing its effect on their reputation. Furthermore, companies should nurture their relationships with investors, aiming to elevate investor attention above the market mean. Policymakers should encourage companies to bolster their ESG performance, even contemplating more rewards and incentives for those with notable ESG achievements. Lastly, auditors should intensify their focus on non-financial information during audits, especially ensuring the accuracy and completeness of a company's ESG reports.

18.
Adv Mater ; 35(15): e2208522, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36692303

RESUMO

Methylammonium (MA)-free formamidinium (FA)-dominated Csx FA1-x PbI3 is rising as the most promising candidate for highly efficient and stable perovskite solar cells. However, the growth of high-quality Csx FA1-x PbI3 black-phase perovskite structure without ion doping in the lattice remains a challenge. Herein, propeller-shaped halogenated tertiary ammonium is synthesized, showing high binding energy on the perovskite surface and large steric hindrance. This molecule can significantly reduce the barrier of high surface energy that suppresses the growth of the α-phase Csx FA1-x PbI3 structure. As a result, the α-phase structure can be formed at room temperature, which can further act as a seed for the growth of high-quality film. Solar cells based on the film show a record efficiency up to 23.6% for MA free Csx FA1- x PbI3 solar cells with inverted structure and excellent stability at 85 °C over 200 h.

19.
Light Sci Appl ; 12(1): 62, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869071

RESUMO

Regulation of perovskite growth plays a critical role in the development of high-performance optoelectronic devices. However, judicious control of the grain growth for perovskite light emitting diodes is elusive due to its multiple requirements in terms of morphology, composition, and defect. Herein, we demonstrate a supramolecular dynamic coordination strategy to regulate perovskite crystallization. The combined use of crown ether and sodium trifluoroacetate can coordinate with A site and B site cations in ABX3 perovskite, respectively. The formation of supramolecular structure retard perovskite nucleation, while the transformation of supramolecular intermediate structure enables the release of components for slow perovskite growth. This judicious control enables a segmented growth, inducing the growth of insular nanocrystal consist of low-dimensional structure. Light emitting diode based on this perovskite film eventually brings a peak external quantum efficiency up to 23.9%, ranking among the highest efficiency achieved. The homogeneous nano-island structure also enables high-efficiency large area (1 cm2) device up to 21.6%, and a record high value of 13.6% for highly semi-transparent ones.

20.
Physiol Genomics ; 44(21): 1063-71, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22991206

RESUMO

Mammalian cells are normally stressed by high interstitial NaCl in the renal medulla and by lesser elevation of NaCl in several other tissues. High NaCl damages proteins and DNA and can kill cells. Known protective responses include nuclear translocation of the transcription factor NFAT5 and other proteins. In order better to understand the extent and significance of changes in nuclear protein abundance, we extracted nuclear and cytoplasmic proteins separately from HEK293 cells and measured by LC-MS/MS (iTRAQ) changes of abundance of proteins in the extracts in response to high NaCl at three time points: 1 h, 8 h, and adapted for two passages. We confidently identified a total of 3,190 proteins; 163 proteins changed significantly at least at one time point in the nucleus. We discerned the biological significance of the changes by Gene Ontology and protein network analysis. Proteins that change in the nucleus include ones involved in protein folding and localization, microtubule-based process, regulation of cell death, cytoskeleton organization, DNA metabolic process, RNA processing, and cell cycle. Among striking changes in the nucleus, we found a decrease of all six 14-3-3 isoforms; dynamic changes of "cytoskeletal" proteins, suggestive of nucleoskeletal reorganization; rapid decrease of tubulins; and dynamic changes of heat shock proteins. Identification of these changes of nuclear protein abundance enhances our understanding of high NaCl-induced cellular stress, and provides leads to previously unknown damages and protective responses.


Assuntos
Proteínas Nucleares/metabolismo , Cloreto de Sódio/metabolismo , Núcleo Celular/metabolismo , Células HEK293 , Humanos , Espectrometria de Massas , Proteômica
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