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1.
J Environ Manage ; 368: 122124, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39126847

RESUMO

The coordination of heterogeneous environmental regulations (HER) is crucial for promoting regional green synergistic development. The primary objective of this study is to evaluate the impact of various heterogeneous environmental regulations (HER) on the green economic transformation (GET) of cities in China. We developed a comprehensive index system to measure the GET across three dimensions: the level of economic green development, the capacity for resource and environmental support, and the level of support for green transformation. This study examines 284 Chinese cities during the period from 2011 to 2020. Applying a dynamic panel model, a dynamic Durbin model, and a synergy model, we explore direct effects, spatial effects, and asymmetry of synergistic effects of HER on the GET of Chinese cities. We find that, in terms of direct effects, all environmental regulations can promote urban GET, though the magnitude of effects is heterogeneous. In terms of spatial spillover effects, market-incentive and public-participation environmental policies in a given region inhibit green transformation in neighboring regions, while overall environmental regulation and command-and-control regulation have significant positive effects on neighboring regions' green transformation. Furthermore, the total short-term effect of HER is significantly higher than the total long-term effect. The synergistic effect of HER is positive for the Beijing-Tianjin-Hebei city cluster and the Yangtze River Delta city cluster. This study can provide valuable policy implications for regional coordinated development with a low-carbon focus.


Assuntos
Cidades , China , Conservação dos Recursos Naturais , Desenvolvimento Econômico , Política Ambiental
2.
Proc Biol Sci ; 291(2024): 20232791, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835273

RESUMO

Sociality underpins major evolutionary transitions and significantly influences the structure and function of complex ecosystems. Social insects, seen as the pinnacle of sociality, have traits like obligate sterility that are considered 'master traits', used as single phenotypic measures of this complexity. However, evidence is mounting that completely aligning both phenotypic and evolutionary social complexity, and having obligate sterility central to both, is erroneous. We hypothesize that obligate and functional sterility are insufficient in explaining the diversity of phenotypic social complexity in social insects. To test this, we explore the relative importance of these sterility traits in an understudied but diverse taxon: the termites. We compile the largest termite social complexity dataset to date, using specimen and literature data. We find that although functional and obligate sterility explain a significant proportion of variance, neither trait is an adequate singular proxy for the phenotypic social complexity of termites. Further, we show both traits have only a weak association with the other social complexity traits within termites. These findings have ramifications for our general comprehension of the frameworks of phenotypic and evolutionary social complexity, and their relationship with sterility.


Assuntos
Isópteros , Comportamento Social , Isópteros/fisiologia , Animais , Evolução Biológica , Fenótipo , Comportamento Animal
3.
ACS Appl Mater Interfaces ; 15(18): 22752-22761, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37119204

RESUMO

Hole-transport materials (HTMs) play an important role in perovskite solar cells (PSCs) to enhance the power conversion efficiency (PCE). The innovation of HTMs can increase the hole extraction ability and reduce interfacial recombination. Three organic small molecule HTMs with 4H-cyclopenta[2,1-b:3,4-b']dithiophene (CPDT) as the central unit was designed and synthesized, namely, CPDTE-MTP (with the 2-ethylhexyl substituent and diphenylamine derivative end-group), CPDT-MTP (with the hexyl substituent and diphenylamine derivative end-group), and CPDT-PMTP (with the hexyl substituent and triphenylamine derivative end-group), which can form bifunctional and robust hole transport layer (HTL) on ITO and is tolerable to subsequent solvent and thermal processing. The X-ray photoelectron spectroscopy (XPS) results proved that CPDT-based HTMs can both interact with ITO through the nitrogen element in them and the tin element in ITO and passivate the upper perovskite layer. It is worth noting that the champion efficiency of MAPbI3 PSCs based on CPDT-PMTP achieved 20.77%, with an open circuit voltage (VOC) of 1.10 V, a short-circuit current (JSC) of 23.39 mA cm-2, and a fill factor (FF) of 80.83%, as three new materials were introduced into p-i-n PSCs as dopant-free HTMs.

4.
Nat Commun ; 14(1): 626, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36746946

RESUMO

Although perovskite X-ray detectors have revealed promising properties, their dark currents are usually hundreds of times larger than the practical requirements. Here, we report a detector architecture with a unique shunting electrode working as a blanking unit to suppress dark current, and it theoretically can be reduced to zero. We experimentally fabricate the dark-current-shunting X-ray detector, which exhibits a record-low dark current of 51.1 fA at 5 V mm-1, a detection limit of 7.84 nGyair s-1, and a sensitivity of 1.3 × 104 µC Gyair-1 cm-2. The signal-to-noise ratio of our polycrystalline perovskite-based detector is even outperforming many previously reported state-of-the-art single crystal-based X-ray detectors by serval orders of magnitude. Finally, the proof-of-concept X-ray imaging of a 64 × 64 pixels dark-current-shunting detector array is successfully demonstrated. This work provides a device strategy to fundamentally reduce dark current and enhance the signal-to-noise ratio of X-ray detectors and photodetectors in general.

5.
Mol Plant Pathol ; 19(12): 2561-2574, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30030900

RESUMO

Pattern recognition receptors (PRRs) can trigger plant immunity through the recognition of pathogen-associated molecular patterns. In this study, we report that a malectin-like/leucine-rich repeat receptor protein kinase gene, RLK-V, from Haynaldia villosa putatively acts as a PRR to positively regulate powdery mildew resistance caused by Blumeria graminis f. sp. tritici (Bgt) in wheat. RLK-V has two alternatively spliced transcripts corresponding to an intact RLK-V1.1 and a truncated RLK-V1.2 caused by intron retention. Expression analysis showed that both transcripts could be up-regulated by Bgt in resistant materials, whereas the functional RLK-V1.1 was expressed only after Bgt inoculation. Promoter activity assays indicated that RLK-V could respond to Bgt even in susceptible wheat. Silencing of RLK-V in Pm21-carrying resistant materials resulted in compromised resistance to Bgt. In addition, over-expression of RLK-V1.1 in Pm21-lacking susceptible Yangmai158 and SM-1 by single-cell transient expression and stable transformation in Yangmai158 could improve powdery mildew resistance. We propose that RLK-V regulates basal resistance to powdery mildew, which is also required for broad-spectrum resistance mediated by the Pm21 gene. Over-expression of RLK-V1.1 could trigger cell death in Nicotiana benthamiana, and RLK-V1.1 transgenic wheat accumulated more reactive oxygen species and displayed a stronger hypersensitive response than did the recipient, which led to enhanced Bgt resistance. However, constitutive activation of RLK-V1.1 resulted in the abnormal growth of transgenic plants.


Assuntos
Ascomicetos/fisiologia , Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas/genética , Triticum/genética , Triticum/microbiologia , Processamento Alternativo/genética , Sequência de Bases , Morte Celular , Cromossomos de Plantas/genética , Suscetibilidade a Doenças , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Proteínas de Repetições Ricas em Leucina , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Vírus de Plantas/fisiologia , Regiões Promotoras Genéticas/genética , Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Nicotiana/microbiologia , Regulação para Cima/genética
6.
Med Phys ; 31(12): 3393-405, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15651622

RESUMO

In a previous article, we presented development and verification of an integral transport equation-based deterministic algorithm for computing three-dimensional brachytherapy dose distributions. Recently, we have included fluorescence radiation physics and parallel computation to the standing algorithms so that we can compute dose distributions for a large set of seeds without resorting to the superposition methods. The introduction of parallel computing capability provided a means to compute the dose distribution for multiple seeds in a simultaneous manner. This provided a way to study strong heterogeneity and shadow effects induced by the presence of multiple seeds in an interstitial brachytherapy implant. This article presents the algorithm for computing fluorescence radiation, algorithm for parallel computing, and display results for an 81-seed implant that has a perfect and imperfect lattice. The dosimetry data for a single model 6711 seeds is presented for verification and heterogeneity factor computations using simultaneous and superposition techniques are presented.


Assuntos
Artefatos , Braquiterapia/instrumentação , Braquiterapia/métodos , Modelos Biológicos , Proteção Radiológica/métodos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Carga Corporal (Radioterapia) , Simulação por Computador , Humanos , Radioisótopos de Irídio/análise , Radioisótopos de Irídio/uso terapêutico , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade
7.
Phys Med Biol ; 48(1): 73-93, 2003 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-12564502

RESUMO

We developed a transport-equation-based deterministic algorithm for computing three-dimensional brachytherapy dose distributions. The deterministic algorithm has been based on the integral transport equation. The algorithm provided us with the capability of computing dose distributions for multiple isotropic point and/or volumetric sources in a homogenous/heterogeneous medium. The algorithm results have been benchmarked against the results from the literature and MCNP results for isotropic point sources and volumetric sources.


Assuntos
Algoritmos , Braquiterapia/métodos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioisótopos do Iodo , Controle de Qualidade , Radiometria/normas , Dosagem Radioterapêutica
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