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1.
Plant Biotechnol J ; 21(7): 1361-1372, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36912620

RESUMO

Nonhost resistance (NHR) is a robust plant immune response against non-adapted pathogens. A number of nucleotide-binding leucine-rich repeat (NLR) proteins that recognize non-adapted pathogens have been identified, although the underlying molecular mechanisms driving robustness of NHR are still unknown. Here, we screened 57 effectors of the potato late blight pathogen Phytophthora infestans in nonhost pepper (Capsicum annuum) to identify avirulence effector candidates. Selected effectors were tested against 436 genome-wide cloned pepper NLRs, and we identified multiple functional NLRs that recognize P. infestans effectors and confer disease resistance in the Nicotiana benthamiana as a surrogate system. The identified NLRs were homologous to known NLRs derived from wild potatoes that recognize P. infestans effectors such as Avr2, Avrblb1, Avrblb2, and Avrvnt1. The identified CaRpi-blb2 is a homologue of Rpi-blb2, recognizes Avrblb2 family effectors, exhibits feature of lineage-specifically evolved gene in microsynteny and phylogenetic analyses, and requires pepper-specific NRC (NLR required for cell death)-type helper NLR for proper function. Moreover, CaRpi-blb2-mediated hypersensitive response and blight resistance were more tolerant to suppression by the PITG_15 278 than those mediated by Rpi-blb2. Combined results indicate that pepper has stacked multiple NLRs recognizing effectors of non-adapted P. infestans, and these NLRs could be more tolerant to pathogen-mediated immune suppression than NLRs derived from the host plants. Our study suggests that NLRs derived from nonhost plants have potential as untapped resources to develop crops with durable resistance against fast-evolving pathogens by stacking the network of nonhost NLRs into susceptible host plants.


Assuntos
Phytophthora infestans , Solanum tuberosum , Phytophthora infestans/fisiologia , Solanum tuberosum/genética , Leucina , Filogenia , Nucleotídeos/metabolismo
2.
Sensors (Basel) ; 23(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005536

RESUMO

An automotive 2.1 µm CMOS image sensor has been developed with a full-depth deep trench isolation and an advanced readout circuit technology. To achieve a high dynamic range, we employ a sub-pixel structure featuring a high conversion gain of a large photodiode and a lateral overflow of a small photodiode connected to an in-pixel storage capacitor. With the sensitivity ratio of 10, the expanded dynamic range could reach 120 dB at 85 °C by realizing a low random noise of 0.83 e- and a high overflow capacity of 210 ke-. An over 25 dB signal-to-noise ratio is achieved during HDR image synthesis by increasing the full-well capacity of the small photodiode up to 10,000 e- and suppressing the floating diffusion leakage current at 105 °C.

3.
New Phytol ; 233(2): 934-947, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34632584

RESUMO

The hypersensitive response (HR) is a robust immune response mediated by nucleotide-binding, leucine-rich repeat receptors (NLRs). However, the early molecular event that links activated NLRs to cell death is unclear. Here, we demonstrate that NLRs target plasma membrane H+ -ATPases (PMAs) that generate electrochemical potential, an essential component of living cells, across the plasma membrane. CCA 309, an autoactive N-terminal domain of a coiled-coil NLR (CNL) in pepper, is associated with PMAs. Silencing or overexpression of PMAs reversibly affects cell death induced by CCA 309 in Nicotiana benthamiana. CCA 309-induced extracellular alkalization causes plasma membrane depolarization, followed by cell death. Coimmunoprecipitation analyses suggest that CCA 309 inhibits PMA activation by preoccupying the dephosphorylated penultimate threonine residue of PMA. Moreover, pharmacological experiments using fusicoccin, an irreversible PMA activator, showed that inhibition of PMAs contributes to CNL-type (but not Toll interleukin-1 receptor NLR-type) resistance protein-induced cell death. We suggest PMAs as primary targets of plasma membrane-associated CNLs leading to HR-associated cell death by disturbing the electrochemical gradient across the membrane. These results provide new insight into NLR-mediated cell death in plants, as well as innate immunity in higher eukaryotes.


Assuntos
Proteínas NLR , Doenças das Plantas , Morte Celular , Membrana Celular/metabolismo , Proteínas NLR/metabolismo , Imunidade Vegetal , Proteínas de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo
4.
J Chem Phys ; 155(2): 024120, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34266276

RESUMO

Due to their optimal bandgap size and large defect tolerance, nitrides are becoming pivotal materials in several optoelectronic devices, photovoltaics, and photocatalysts. A computational method that can accurately predict their electronic structures is indispensable for exploring new nitride materials. However, the relatively small bandgap of nitrides, which stems from the subtle balance between ionic and covalent bond characteristics, makes conventional density functional theory challenging to achieve satisfactory accuracy. Here, we employed a self-consistent hybrid functional where the Hartree-Fock mixing parameter is self-consistently determined and thus the empiricism of the hybrid functional is effectively removed to calculate the bandgaps of various nitride compounds. By comparing the bandgaps from the self-consistent hybrid functional calculations with the available experimental and high-level GW calculation results, we found that the self-consistent hybrid functional can provide a computationally efficient approach for quantitative predictions of nitride electronic structures with an accuracy level comparable to the GW method. Additionally, we aligned the band edge positions of various nitride compounds using self-consistent hybrid functional calculations, providing material design principles for heterostructures of nitride-based optoelectronic devices. We anticipate the wide use of the self-consistent hybrid functional for accelerating explorations and predictions of new nitride-based functional materials in various photoactive applications.

5.
New Phytol ; 215(3): 1132-1143, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28631815

RESUMO

Chemical barriers contribute to nonhost resistance, which is defined as the resistance of an entire plant species to nonadapted pathogen species. However, the molecular basis of metabolic defense in nonhost resistance remains elusive. Here, we report genetic evidence for the essential role of phytoalexin capsidiol in nonhost resistance of pepper (Capsicum spp.) to potato late blight Phytophthora infestans using transcriptome and genome analyses. Two different genes for capsidiol biosynthesis, 5-epi-aristolochene synthase (EAS) and 5-epi-aristolochene-1,3-dihydroxylase (EAH), belong to multigene families. However, only a subset of EAS/EAH gene family members were highly induced upon P. infestans infection, which was associated with parallel accumulation of capsidiol in P. infestans-infected pepper. Silencing of EAS homologs in pepper resulted in a significant decrease in capsidiol accumulation and allowed the growth of nonadapted P. infestans that is highly sensitive to capsidiol. Phylogenetic and genomic analyses of EAS/EAH multigene families revealed that the emergence of pathogen-inducible EAS/EAH genes in Capsicum-specific genomic regions rendered pepper a nonhost of P. infestans. This study provides insights into evolutionary aspects of nonhost resistance based on the combination of a species-specific phytoalexin and sensitivity of nonadapted pathogens.


Assuntos
Vias Biossintéticas/genética , Capsicum/genética , Resistência à Doença/genética , Família Multigênica , Phytophthora infestans/fisiologia , Doenças das Plantas/microbiologia , Sesquiterpenos/metabolismo , Solanum tuberosum/microbiologia , Alquil e Aril Transferases/metabolismo , Capsicum/microbiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genoma de Planta , Filogenia , Doenças das Plantas/genética , Sesquiterpenos/química , Especificidade da Espécie , Transcriptoma/genética
6.
J Phys Chem Lett ; 15(17): 4575-4580, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38639559

RESUMO

Many studies have focused on tailoring the photophysical properties of two-dimensional (2D) materials for photocatalytic (PC) or photoelectrochemical (PEC) applications. To understand the optical properties of 2D materials in solution, we established a computational method that combined the Bethe-Salpeter equation (BSE) calculations with our GW-GPE method, allowing for GW/BSE-level calculations with implicit solvation described using the generalized Poisson equation (GPE). We applied this method to MoS2, phosphorene (PP), and g-C3N4 and found that when the solvent dielectric increased, it reduced the exciton binding energy and quasiparticle bandgap, resulting in almost no solvatochromic shift in the excitonic peaks of MoS2 and PP, which is consistent with previous experiments. However, our calculations predicted that the solvent dielectric had a significant impact on the excitonic properties of g-C3N4, exhibiting a large solvatochromic shift. We expect that our GW/BSE-GPE method will offer insights into the design of 2D materials for PC and PEC applications.

7.
RSC Adv ; 14(10): 7081-7087, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38414988

RESUMO

SnSe2 with its layered structure is a promising thermoelectric material with intrinsically low lattice thermal conductivity. However, its poor electronic transport properties have motivated extensive doping studies. Br doping effectively improves the power factor and converts the dimorphic SnSe2 to a fully hexagonal structure. To understand the mechanisms underlying the power factor improvement of Br-doped SnSe2, the electronic band parameters of Br-doped dimorphic and hexagonal SnSe2 should be evaluated separately. Using the single parabolic band model, we estimate the intrinsic mobility and effective mass of the Br-doped dimorphic and hexagonal SnSe2. While Br doping significantly improves the mobility of dimorphic SnSe2 (with the dominant hexagonal phase), it results in a combination of band convergence and band flattening in fully hexagonal SnSe2. Br-doped dimorphic SnSe2 is predicted to exhibit higher thermoelectric performance (zT ∼0.23 at 300 K) than Br-doped fully hexagonal SnSe2 (zT ∼0.19 at 300 K). Characterisation of the other, currently unidentified, structural phases of dimorphic SnSe2 will enable us to tailor the thermoelectric properties of Br-doped SnSe2.

8.
ACS Nano ; 17(23): 23732-23745, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38039389

RESUMO

Defect engineering provides an effective way to explore efficient nanostructured catalysts. Herein, we synthesize defect-regulated two-dimensional superlattices comprising interstratified holey g-C3N4 and TiO2 monolayers with tailorable interfacial coupling. Using this interfacial-coupling-controlled hybrid system, a strong interdependence among vacancy content, performance, and interfacial coupling was elucidated, offering key insights for the design of high-performance catalysts. The defect-optimized g-C3N4-TiO2 superlattice exhibited higher photocatalytic activity toward visible-light-induced N2 fixation (∼1.06 mmol g-1 h-1) than defect-unoptimized and disorderly assembled g-C3N4-TiO2 homologues. The high photocatalytic performance of g-C3N4-TiO2 was attributed to the hybridization-induced defect creation, facilitated hydrogenation of adsorbed nitrogen, and improvement in N2 adsorption and charge transport. A comparison of the defect-dependent photocatalytic activity of g-C3N4, g-C3N4 nanosheets, and g-C3N4-TiO2 revealed the presence of optimal defect content for improving photocatalytic performance and the continuous increase of hybridization impact with the defect content. Sophisticated mutual influence among defect, electronic coupling, and photocatalytic ability underscores the importance of defect fine control in exploring high-performance hybrid photocatalysts. Along with the DFT calculation, the excellent photocatalyst performance of defect-optimized g-C3N4-TiO2 can be ascribed to the promotion of the uphill *N hydrogenation step as well as to enhancement of N2 adsorption, charge transfer kinetics, and mass transports.

9.
Angiology ; : 33197231225281, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38147027

RESUMO

Pancreaticoduodenal and gastroduodenal artery aneurysms (PDAAs and GDAAs) are rare visceral aneurysms. Considering the rupture risk regardless of size, treatment should be provided promptly. We reviewed the characteristics and management of peripancreatic aneurysms in a retrospective, single-center review of consecutive patients with PDAAs and GDAAs between 2000 and 2022. Demographics, clinical characteristics, radiologic features, treatment, and outcomes were recorded. Nineteen PDAAs and seven GDAAs were identified in 24 patients. The median sizes of the PDAAs and GDAAs were 21 mm (range: 8-50 mm) and 14 mm (range: 11-32 mm), respectively. There were 4 ruptured cases (15.4%). Ten aneurysms (38.5%) had concomitant visceral aneurysms, and 16 (61.6%) were associated with celiac pathology. Aneurysms were managed using endovascular in 12 (46.2%), surgical in 4 (15.4%), and combined methods in 3 (11.5%) cases; 7 patients (26.9%) were lost to follow-up or refused treatments. During a median 13.8-month follow-up (range: 1-147.6), two complications (7.7%) occurred including pancreatitis and coil migration into the superior mesenteric artery after embolization within 30 days. After 30 days, aorto-common hepatic artery bypass graft stenosis was identified in one PDAA. Depending on the characteristics of peripancreatic aneurysms, endovascular, surgical, and hybrid approaches might all be practical treatment options.

10.
J Phys Chem Lett ; 13(32): 7574-7582, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35948424

RESUMO

Computational simulations have become of major interest to screen potential photocatalysts for optimal band edge positions which straddle the redox potentials. Unfortunately, these methods suffer from a difficulty in resolving the dynamic solvent response on the band edge positions. We have developed a computational method based on the GW approximation coupled with an implicit solvation model that solves a generalized Poisson equation (GPE), that is, GW-GPE. Using GW-GPE, we have investigated the band edge locations of (quasi) 2D materials immersed in water and found a good agreement with experimental data. We identify two contributions of the solvent effect, termed a "polarization-field effect" and an "environmental screening effect", which are found to be highly sensitive to the atomic and charge distribution of the 2D materials. We believe that the GW-GPE scheme can pave the way to predict band edge positions in solvents, enabling design of 2D material-based photocatalysts and energy systems.

11.
Adv Sci (Weinh) ; 9(2): e2103042, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34761539

RESUMO

The hybridization of conductive nanospecies has garnered significant research interest because of its high efficacy in improving the diverse functionalities of nanostructured materials. In this study, a novel synthetic strategy is developed to optimize the defect structure, structural ordering, and energy-related functionality of nanostructured-materials by employing a multilayer multicomponent two-dimenstional (2D) graphene/metal oxide/graphene nanosheet (NS) as a versatile hybridization matrix. The hybridization of the robust trilayer, polydiallyldiammonium (PDDA)-anchored reduced-graphene oxide (prGO)/metal oxide/prGO NS effectively enhance the structural ordering and porosity of the hybridized MoS2 /MnO2 NS through suppression of defect formation and tight stacking. In comparison with monolayer rGO/RuO2 NS-based homologs, the 2D superlattice trilayer prGO/RuO2 /prGO NS hybrids deliver better functionalities as a hydrogen evolution electrocatalyst and as a supercapacitor electrode, demonstrating the merits of hybridization with multilayer NSs. The advantages of using multilayer multicomponent conductive NSs as hybridization matrices arise from the enhancement of charge and mass transport through the layer flattening or defect suppression of the hybridized NSs and the increase in porosity, as evidenced by density functional theory calculations. Finally, the universal utility of multilayer NSs is confirmed by investigating the strong effect of the stacking order on the electrocatalytic functionality of MoS2 /rGO/RuO2 films fabricated through layer-by-layer deposition.

12.
BMJ Open Sport Exerc Med ; 7(1): e000689, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614125

RESUMO

OBJECTIVE: The increasing incidence of sports injury among athletes calls for systemic surveillance of injuries and illnesses in this field to develop preventive measures. The patterns of injuries and illnesses that occurred among Korean athletes during the 2018 Asian Games held in Indonesia were studied. METHODS: We recorded the occurrence of all injuries and illnesses reported to the chief medical officer, coordinated with the help of an instant social messaging application in real time. RESULTS: A total of 782 elite athletes participated in 46 sporting events. A total of 141 (18.03%) injuries were recorded, with 121 (15.47%) athletes suffering at least one injury. Out of 141 injuries 80 (56.74%) were in male athletes and 61 (43.26%) were in female athletes. The highest number of injuries was seen among sport climbing athletes (n=10, 71.43%), followed by sepak takraw. A total of 16 (11.35%) injuries were expected to prevent athletes from participation in competition/training. Most of the injuries occurred during training (46.10%), with lower lumbar spine being the most common part injured. A total of 209 (26.72%) illnesses were reported, with at least one illness in 170 (21.73%) athletes. The incidence among female athletes (26.90%) was comparable with that of male athletes (26.90%). Maximum illness rate was reported in table tennis (100%). The most common system involved was gastrointestinal (n=93, 44.49%), followed by respiratory (n=53, 25.36%). Environmental factors were causative in 111 athletes (53.11%) and infection in 79 (37.79%). Illnesses resulted in loss of at least 1 day among 30 (14.35%) athletes. CONCLUSION: Overall 15.47% of athletes suffered at least one injury and 21.73% suffered at least one illness; the incidence of injury and illness varied depending on the type of sports.

13.
Nat Commun ; 12(1): 1856, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767159

RESUMO

Electrocatalytic conversion of nitrogen oxides to value-added chemicals is a promising strategy for mitigating the human-caused unbalance of the global nitrogen-cycle, but controlling product selectivity remains a great challenge. Here we show iron-nitrogen-doped carbon as an efficient and durable electrocatalyst for selective nitric oxide reduction into hydroxylamine. Using in operando spectroscopic techniques, the catalytic site is identified as isolated ferrous moieties, at which the rate for hydroxylamine production increases in a super-Nernstian way upon pH decrease. Computational multiscale modelling attributes the origin of unconventional pH dependence to the redox active (non-innocent) property of NO. This makes the rate-limiting NO adsorbate state more sensitive to surface charge which varies with the pH-dependent overpotential. Guided by these fundamental insights, we achieve a Faradaic efficiency of 71% and an unprecedented production rate of 215 µmol cm-2 h-1 at a short-circuit mode in a flow-type fuel cell without significant catalytic deactivation over 50 h operation.

14.
Nat Commun ; 11(1): 4309, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855400

RESUMO

'Ideal' transparent p-type semiconductors are required for the integration of high-performance thin-film transistors (TFTs) and circuits. Although CuI has recently attracted attention owing to its excellent opto-electrical properties, solution processability, and low-temperature synthesis, the uncontrolled copper vacancy generation and subsequent excessive hole doping hinder its use as a semiconductor material in TFT devices. In this study, we propose a doping approach through soft chemical solution process and transparent p-type Zn-doped CuI semiconductor for high-performance TFTs and circuits. The optimised TFTs annealed at 80 °C exhibit a high hole mobility of over 5 cm2 V-1 s-1 and high on/off current ratio of ~107 with good operational stability and reproducibility. The CuI:Zn semiconductors show intrinsic advantages for next-generation TFT applications and wider applications in optoelectronics and energy conversion/storage devices. This study paves the way for the realisation of transparent, flexible, and large-area integrated circuits combined with n-type metal-oxide semiconductor.

15.
Front Immunol ; 10: 530, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949176

RESUMO

Recent studies have reported an increased incidence of inflammatory bowel disease (IBD) in patients with pulmonary diseases. Despite clinical and epidemiological studies of the interplay between colitis and asthma, the diseases' related underlying mechanisms remain unclear. In this study, we evaluated the development of colitis in a model of allergic airway inflammation. We revealed that intratracheal chronic ovalbumin (OVA) exposure induces colitis and allergic airway inflammation. Interestingly, induction of colitis was largely regulated by Th1, rather than Th2 responses, whereas allergic airway inflammation was primarily mediated by Th2 responses. Experiments in Tbx21 (T-bet) and Ifng (IFN-γ) deficient mice have confirmed that IFN-γ is a major mediator involved in OVA-induced colitis. These findings broaden current understanding of allergen induced colitis pathology and could play a role in the development of novel clinical treatment strategies for asthmatic patients who are at risk of developing colitis.


Assuntos
Colite/imunologia , Interferon gama/imunologia , Ovalbumina/toxicidade , Transdução de Sinais/imunologia , Células Th1/imunologia , Células Th2/imunologia , Animais , Colite/induzido quimicamente , Colite/genética , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Interferon gama/genética , Camundongos , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia
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