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1.
Phytopathology ; : PHYTO08230287R, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38451704

RESUMO

HC-Pro and coat protein (CP) genes of a potyvirus facilitate cell-to-cell movement and are involved in the systemic movement of the viruses. The interaction between HC-Pro and CP is mandatory for aphid transmission. Two turnip mosaic virus (TuMV) isolates, RC4 and YC5, were collected from calla lily plants in Taiwan. The virus derived from the infectious clone pYC5 cannot move systemically in Chenopodium quinoa plants and loses aphid transmissibility in Nicotiana benthamiana plants, like the initially isolated virus. Sequence analysis revealed that two amino acids, P5 and A206, of YC5 CP uniquely differ from RC4 and other TuMV strains. Recombination assay and site-directed mutagenesis revealed that the fifth residue of leucine (L) at the N-terminal region of the CP (TuMV-RC4), rather than proline (P) (TuMV-YC5), is critical to permit the systemic spread in C. quinoa plants. Moreover, the single substitution mutant YC5-CPP5L became aphid transmissible, similar to RC4. Fluorescence microscopy revealed that YC5-GFP was restricted in the petioles of inoculated leaves, whereas YC5-CPP5L-GFP translocated through the petioles of inoculated leaves, the main stem, and the petioles of the upper uninoculated leaves of C. quinoa plants. In addition, YC5-GUS was blocked at the basal part of the petiole connecting to the main stem of the inoculated C. quinoa plants, whereas YC5-CPP5L-GFP translocated to the upper leaves. Thus, a single amino acid, the residue L5 at the N-terminal region right before the 6DAG8 motif, is critical for the systemic translocation ability of TuMV in a local lesion host and for aphid transmissibility in a systemic host.

2.
Mol Plant Microbe Interact ; 36(6): 345-358, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36794975

RESUMO

East Asian passiflora virus (EAPV) seriously affects passionfruit production in Taiwan and Vietnam. In this study, an infectious clone of the EAPV Taiwan strain (EAPV-TW) was constructed, and EAPV-TWnss, with an nss tag attached to its helper component-protease (HC-Pro), was generated for monitoring the virus. Four conserved motifs of EAPV-TW HC-Pro were manipulated to create single mutations of F8I (simplified as I8), R181I (I181), F206L (L206), and E397N (N397) and double mutations of I8I181, I8L206, I8N397, I181L206, I181N397, and L206N397. Four mutants, EAPV I8I181, I8N397, I181L206, and I181N397, infected Nicotiana benthamiana and yellow passionfruit plants without conspicuous symptoms. Mutants EAPV I181N397 and I8N397 were stable after six passages in yellow passionfruit plants and expressed a zigzag pattern of accumulation dynamic, typical of beneficial protective viruses. An agroinfiltration assay indicated that the RNA silencing suppression capabilities of the four double mutated HC-Pros are significantly reduced. Mutant EAPV I181N397 accumulated the highest level of the small interfering RNA at 10 days postinoculation (dpi) in N. benthamiana plants, then dropped to background levels after 15 dpi. In both N. benthamiana and yellow passionfruit plants, EAPV I181N397 conferred complete cross protection (100%) against severe EAPV-TWnss, as defined by no severe symptoms and absence of the challenge virus, checked by Western blotting and reverse transcription PCR. Mutant EAPV I8N397 provided high degrees of complete protection against EAPV-TWnss in yellow passionfruit plants (90%) but not in N. benthamiana plants (0%). Both mutants showed complete protection (100%) against the Vietnam severe strain EAPV-GL1 in passionfruit plants. Thus, the mutants EAPV I181N397 and I8N397 have excellent potential for controlling EAPV in Taiwan and Vietnam. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Proteção Cruzada , Passiflora , Doenças das Plantas , Potyvirus , Passiflora/virologia , Potyvirus/genética , Interferência de RNA , Nicotiana , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia
3.
Phytopathology ; 113(2): 334-344, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36129763

RESUMO

Papaya (Carica papaya) production is seriously limited by papaya ringspot virus (PRSV) worldwide, including in Vietnam. Control of PRSV by cross protection is dependent on the availability of effective mild strains. Here, an infectious cDNA clone was constructed from PRSV isolate TG5 from South Vietnam. Site-directed mutagenesis with point mutations on the essential motifs of the helper component proteinase (HC-Pro) was performed, with or without deleting five amino acids (d5) from its N-terminal region. Mutants TG-d5, TG-d5I7, and TG-d5L206 containing d5, d5 + F7I, and d5 + F206L, respectively, induced mild mottling followed by symptomless recovery on papaya and infected Chenopodium quinoa without lesion formation. Each mutant accumulated in papaya at reduced levels with a zigzag pattern and was stable beyond six monthly passages. The cross-protection effectiveness of the three mutants in papaya against TG5 was investigated, each with 60 plants from three independent trials. The results showed that each mutant provided complete protection (100%) against TG5, 1 month after the challenge inoculation, as verified by the lack of severe symptoms and lack of local lesions in C. quinoa. Further tests revealed that TG-d5I7 also confers high levels of protection against other severe PRSV isolates from South Vietnam, including isolates DN (97%) and ST2 (50%). However, TG-d5I7 is ineffective or less effective (0 to 33%) against seven other severe PRSV strains from different geographic origins, including the isolate HN from North Vietnam. Our results indicate that the protection by the three mutants is highly strain-specific and suitable for the control of PRSV in South Vietnam.


Assuntos
Carica , Potyvirus , Peptídeo Hidrolases/metabolismo , Vietnã , Proteção Cruzada , Doenças das Plantas/prevenção & controle , Potyvirus/genética , Gerenciamento Clínico
4.
Phytopathology ; 113(8): 1583-1594, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36935377

RESUMO

The application of attenuated viruses has been widely practiced for protecting crops from infection by related severe strains of the same species. Papaya ringspot virus W-type (PRSV W) and zucchini yellow mosaic virus (ZYMV) devastate cucurbits worldwide. However, the prevailing of these two viruses in cucurbits cannot be prevented by a single protective virus. In this study, we disclosed that co-infection of horn melon plants by two mild strains, PRSV P-type (PRSV P) HA5-1 and ZYMV-ZAC (a previously developed mild mutant of ZYMV) confers concurrent protection against PRSV P and ZYMV. Consequently, mild mutants of PRSV W were created by site-directed mutagenesis through modifications of the pathogenicity motifs FRNK and PD in helper component-protease (HC-Pro). A stable PRSV W mutant WAC (PRSV-WAC) with R181I and D397N mutations in HC-Pro was generated, inducing mild mottling, followed by symptomless recovery in cucurbits. Horn melon plants pre-infected by PRSV-WAC and ZYMV-ZAC showed no apparent interference on viral accumulation with no synergistic effects on symptoms. An agroinfiltration assay of mixed HC-Pros of WACHC-Pro + ZACHC-Pro revealed no additive effect of RNA silencing suppression. PRSV-WAC or ZYMV-ZAC alone only antagonized a severe strain of homologous virus, while co-infection with these two mild strains provided complete protection against both PRSV W and ZYMV. Similar results were reproduced in muskmelon and watermelon plants, indicating the feasibility of a two-in-one vaccine for concurrent control of PRSV W and ZYMV in cucurbits.


Assuntos
Afídeos , Coinfecção , Cucurbitaceae , Potyvirus , Animais , Doenças das Plantas , Potyvirus/genética
5.
Plant Dis ; 107(6): 1757-1768, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36401850

RESUMO

Cross protection application of HA5-1, an attenuated mutant of papaya ringspot virus (PRSV) HA strain from Hawaii, was withdrawn from Taiwan due to the narrow geographic strain specificity of HA5-1. Here, to overcome this problem, we created attenuated mutants of PRSV YK, a dominant severe strain from Taiwan, by mutating helper component protease (HC-Pro) at F7, R181, F206, and D397 residues critical for potyviral pathogenicity. PRSV YK HC-Pro R181I, F206L, and D397N single-mutant viruses induced mild symptoms, but their adverse effects on growth of papaya plants disqualified them as useful protective viruses. However, F7I single-mutant and F7I + F206L double-mutant viruses displayed mild symptoms followed by recovery, and they showed a zigzag pattern of accumulation in papaya plants, indicating their potential to trigger RNA silencing and retain partial antagonistic suppression of host defense. Although F7I + R181I and F7I + D397N double-mutant viruses caused symptomless infection, they accumulated barely above mock level and, thus, were not qualified as proper protective viruses. RNA silencing suppression (RSS) analysis by agroinfiltration in Nicotiana benthamiana plants revealed that the HC-Pro F7I and F7I + F206L mutant proteins were weaker in RSS ability than the wild-type protein. Under greenhouse conditions, F7I and F7I + F206L mutant viruses were genetically stable but not aphid transmissible. Compared with the HA5-1 mutant's low degree (10%) of protection to papaya plants, the F7I and F7I + F206L mutants provided complete (100%) protection to papaya and horn melon plants against strain YK. Thus, F7I and F7I + F206L mutants solve the problem of strain-specific protection and have great potential for control of PRSV in Taiwan.


Assuntos
Proteção Cruzada , Proteínas Virais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Cisteína Endopeptidases/metabolismo
6.
Sensors (Basel) ; 23(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37177475

RESUMO

In addition to traditional battery exchange services and stationary charging stations, researchers have proposed wireless charging technology, such as decentralized laser charging or drone-to-drone charging in flight, to provide power to drones with insufficient battery electricity. However, the charging methods presented in the literature will inevitably cause drones to wait in line for charging during peak hours and disrupt their scheduled trips when the number of drones grows rapidly in the future. To the best of our knowledge, there have been no integrated solutions for drone flight path and charging planning to alleviate charging congestion, taking into account the different mission characteristics of drones and the charging cost considerations of drone operators. Accordingly, this paper provides adaptive charging options to help drone operators to solve the above-mentioned problems. Drones on ordinary missions can use conventional battery swap services, wired charging stations, or electromagnetic wireless charging stations to recharge their batteries as usual, whereas drones on time-critical missions can choose drone-to-drone wireless charging or decentralized laser charging deployed along the fight paths to charge the batteries of drones in flight. Notably, since fixed-wing drones have larger wing areas to install solar panels, they can also use solar energy to charge during flight if the weather is clear. The simulation results exhibited that the proposed work reduced the power load of the power grid during peak hours, met the charging needs of each individual drone during flight, and cut down the charging costs of drone operators. As a result, an all-win situation for drone operators, drone customers, and power grid operators was achieved.

7.
Sensors (Basel) ; 23(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37765823

RESUMO

The popularity of video services such as video call or video on-demand has made it impossible for people to live without them in their daily lives. It can be anticipated that the explosive growth of vehicular communication owing to the widespread use of in-vehicle video infotainment applications in the future will result in increasing fragmentation and congestion of the wireless transmission spectrum. Accordingly, effective bandwidth management algorithms are demanded to achieve efficient communication and stable scalability in next-generation vehicular networks. To the best of our current knowledge, a noticeable gap remains in the existing literature regarding the application of the latest advancements in network communication technologies. Specifically, this gap is evident in the lack of exploration regarding how cutting-edge technologies can be effectively employed to optimize bandwidth allocation, especially in the realm of video service applications within the forthcoming vehicular networks. In light of this void, this paper presents a seamless integration of cutting-edge 6G communication technologies, such as terahertz (THz) and visible light communication (VLC), with the existing 5G millimeter-wave and sub-6 GHz base stations. This integration facilitates the creation of a network environment characterized by high transmission rates and extensive coverage. Our primary aim is to ensure the uninterrupted playback of real-time video applications for vehicle users. These video applications encompass video conferencing, live video, and on-demand video services. The outcomes of our simulations convincingly indicate that the proposed strategy adeptly addresses the challenge of bandwidth competition among vehicle users. Moreover, it notably boosts the efficient utilization of bandwidth from less crowded base stations, optimizes the fulfillment of bandwidth prerequisites for various video applications, and elevates the overall video quality experienced by users. Consequently, our findings serve as a successful validation of the practicality and effectiveness of the proposed methodology.

8.
Nano Lett ; 21(5): 2207-2215, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33600178

RESUMO

In this paper, a universal approach toward constructing a new bilayer device architecture, a few-nanometer-thick third-component layer on a bulk-heterojunction (BHJ) binary blend layer, has been demonstrated in two different state-of-the-art organic photovoltaic (OPV) systems. Through a careful selection of a third component, the power conversion efficiency (PCE) of the device based on PM6/Y6/layered PTQ10 layered third-component structure was 16.8%, being higher than those of corresponding devices incorporating the PM6/Y6/PTQ10 BHJ ternary blend (16.1%) and the PM6/Y6 BHJ binary blend (15.5%). Also, the device featuring PM7/Y1-4F/layered PTQ10 layered third-component structure gave a PCE of 15.2%, which is higher than the PCEs of the devices incorporating the PM7/Y1-4F/PTQ10 BHJ ternary blend and the PM7/Y1-4F BHJ binary blend (14.2 and 14.0%, respectively). These enhancements in PCE based on layered third-component structure can be attributed to improvements in the charge separation and charge collection abilities. This simple concept of the layered third-component structure appears to have great promise for achieving high-performance OPVs.

9.
Phytopathology ; 111(9): 1675-1685, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33487021

RESUMO

Passionfruit plantings in Vietnam increased to 10,000 ha in 2019. However, outbreaks of passionfruit woodiness disease (PWD) have become a serious threat to production. In this study, five virus isolates (DN1, DN4, NA1, GL1, and GL2) were collected from different areas of Vietnam. Their causal roles in PWD were verified by back-inoculation to passionfruit. Analyses of coat protein (CP) and genomic sequences revealed that the GL1 isolate is closely related to East Asia Passiflora virus (EAPV) AO strain of Japan (polyprotein nt and aa identities of 98.1 and 98.2%, respectively), and the GL2 isolate is related to Telosma mosaic virus (TelMV) isolate PasFru, China (polyprotein nt and aa identities of 87.1 and 90.9%, respectively). CP comparison, host range, and cytological characterization indicated that DN1, DN4, and NA1 are potyviruses but are different from EAPV and TelMV. Phylogenic analyses of their CP and genome sequences indicated that these three isolates and the passionfruit severe mottle-associated virus Fujian isolate of China belong to a distinct clade, which does not meet the threshold (76% nt identity of polyprotein) to be regarded as any of potyviral species. Thus, a new species name, Passiflora mottle virus, (PaMoV), has been proposed by the International Committee on Taxonomy of Viruses. A rabbit antiserum was produced against the CP of DN1, and it can distinguish PaMoV from TelMV and EAPV in western blotting and enzyme-linked immunosorbent assay (ELISA) without cross-reactions. Field surveys of 240 samples by ELISA and reverse transcription PCR found that PWD in Vietnam is caused mainly by PaMoV, followed by EAPV, mixed infection of PaMoV and EAPV, and rare cases of TelMV.


Assuntos
Passiflora , Potyvirus , Animais , China , Doenças das Plantas , Potyvirus/genética , Coelhos , Vietnã
10.
Nano Lett ; 20(1): 715-721, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31870153

RESUMO

Bulk heterojunction (BHJ) structure based organic photovoltaics (OPVs) have recently showed great potential for achieving high power conversion efficiencies (PCEs). An ideal BHJ structure would feature large donor/acceptor interfacial areas for efficient exciton dissociation and gradient distributions with high donor and acceptor concentrations near the anode and cathode, respectively, for efficient charge extraction. However, the random mixing of donors and acceptors in the BHJ often suffers the severe charge recombination in the interface, resulting in poor charge extraction. Herein, we propose a new approach-treating the surface of the zinc oxide (ZnO) as an electron transport layer with potassium hydroxide-to induce vertical phase separation of an active layer incorporating the nonfullerene acceptor IT-4F. Density functional theory calculations suggested that the binding energy difference between IT-4F and the PBDB-T-2Cl, to the potassium (K)-presenting ZnO interface, is twice as strong as that for IT-4F and PBDB-T-2Cl to the untreated ZnO surface, such that it would induce more IT-4F moving toward the K-presenting ZnO interface than the untreated ZnO interface thermodynamically. Benefiting from efficient charge extraction, the best PCEs increased to 12.8% from 11.8% for PBDB-T-2Cl:IT-4F-based devices, to 12.6% from 11.6% for PBDB-T-2Cl:Y1-4F-based devices, to 13.5% from 12.2% for PBDB-T-2Cl:Y6-based devices, and to 15.7% from 15.1% for PM6:Y6-based devices.

11.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445289

RESUMO

The NSs protein and the nucleocapsid protein (NP) of orthotospoviruses are the major targets for serological detection and diagnosis. A common epitope of KFTMHNQIF in the NSs proteins of Asia orthotospoviruses has been applied as an epitope tag (nss-tag) for monitoring recombinant proteins. In this study, a monoclonal antibody TNP MAb against the tomato spotted wilt virus (TSWV) NP that reacts with TSWV-serogroup members of Euro-America orthotospoviruses was produced. By truncation and deletion analyses of TSWV NP, the common epitope of KGKEYA was identified and designated as the np sequence. The np sequence was successfully utilized as an epitope tag (np-tag) to monitor various proteins, including the green fluorescence protein, the coat protein of the zucchini yellow mosaic virus, and the dust mite chimeric allergen Dp25, in a bacterial expression system. The np-tag was also applied to investigate the protein-protein interaction in immunoprecipitation. In addition, when the np-tag and the nss-tag were simultaneously attached at different termini of the expressed recombinant proteins, they reacted with the corresponding MAbs with high sensitivity. Here, we demonstrated that the np sequence and TNP MAb can be effectively applied for tagging and detecting proteins and can be coupled with the nss-tag to form a novel epitope-tagging system for investigating protein-protein interactions.


Assuntos
Mapeamento de Epitopos , Imuno-Histoquímica/métodos , Proteínas do Nucleocapsídeo/imunologia , Vírus de Plantas/imunologia , América , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Epitopos/análise , Epitopos/química , Europa (Continente) , Imunoprecipitação , Vírus do Mosaico/química , Vírus do Mosaico/classificação , Vírus do Mosaico/imunologia , Proteínas do Nucleocapsídeo/química , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Vírus de Plantas/química , Vírus de Plantas/classificação , Potyvirus/química , Potyvirus/imunologia , Coloração e Rotulagem/métodos , Tospovirus/química , Tospovirus/classificação , Tospovirus/imunologia
12.
Nano Lett ; 19(8): 5053-5061, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31298866

RESUMO

Solution-processed organic photovoltaics (OPVs) based on bulk-heterojunctions have gained significant attention to alleviate the increasing demend of fossil fuel in the past two decades. OPVs combined of a wide bandgap polymer donor and a narrow bandgap nonfullerene acceptor show potential to achieve high performance. However, there are still two reasons to limit the OPVs performance. One, although this combination can expand from the ultraviolet to the near-infrared region, the overall external quantum efficiency of the device suffers low values. The other one is the low open-circuit voltage (VOC) of devices resulting from the relatively downshifted lowest unoccupied molecular orbital (LUMO) of the narrow bandgap. Herein, the approach to select and incorporate a versatile third component into the active layer is reported. A third component with a bandgap larger than that of the acceptor, and absorption spectra and LUMO levels lying within that of the donor and acceptor, is demonstrated to be effective to conquer these issues. As a result, the power conversion efficiencies (PCEs) are enhanced by the elevated short-circuit current and VOC; the champion PCEs are 11.1% and 13.1% for PTB7-Th:IEICO-4F based and PBDB-T:Y1 based solar cells, respectively.

13.
Mol Plant Microbe Interact ; 31(1): 86-100, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29090655

RESUMO

The viral infection process is a battle between host defense response and pathogen antagonizing action. Several studies have established a tight link between the viral RNA silencing suppressor (RSS) and the repression of salicylic acid (SA)-mediated defense responses, nonetheless host factors directly linking an RSS and the SA pathway remains unidentified. From yeast two-hybrid analysis, we identified an interaction between the potyviral RSS helper-component proteinase (HCPro) and SA-binding protein SABP3. Co-localization and bimolecular fluorescence complementation analyses validated the direct in vivo interaction between Turnip mosaic virus (TuMV) HCPro and the Arabidopsis homologue of SABP3, AtCA1. Additionally, transient expression of TuMV HCPro demonstrated its ability to act as a negative regulator of AtCA1. When the plants of the AtCA1 knockout mutant line were inoculated with TuMV, our results indicated that AtCA1 is essential to restrict viral spreading and accumulation, induce SA accumulation, and trigger the SA pathway. Unexpectedly, the AtCA1 overexpression line also displayed a similar phenotype, suggesting that the constitutive expression of AtCA1 antagonizes the SA pathway. Taken together, our results depict AtCA1 as an essential regulator of SA defense responses. Moreover, the interaction of potyviral HCPro with this regulator compromises the SA pathway to weaken host defense responses and facilitate viral infection.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/virologia , Anidrases Carbônicas/metabolismo , Cisteína Endopeptidases/metabolismo , Inativação Gênica , Potyvirus/metabolismo , Ácido Salicílico/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , Cisteína Endopeptidases/química , Fluorescência , Técnicas de Inativação de Genes , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas , Ligação Proteica , Proteínas Virais/química
14.
Stereotact Funct Neurosurg ; 95(3): 142-148, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28486221

RESUMO

PURPOSE: To analyze and compare the characteristics of dose distributions for Leksell Gamma Knife Perfexion (LGK-PFX) and CyberKnife (CK) in treating arteriovenous malformations (AVMs). SUBJECTS AND METHODS: Twenty-four patients with AVMs who received CK radiosurgery at a prescribed dose (PD) of 16-25 Gy in a single fraction were selected. A LGK-PFX treatment plan with the same PD was designed for each patient. Dosimetric values for both systems were compared with respect to the conformity index (CI); selectivity index (SI); gradient index (GI) of 75, 50, and 25% of the PD; heterogeneity index; volume of the brain tissue covered by doses of 10 and 12 Gy; maximum dose delivered to the brainstem; and beam-on time. RESULTS: The CIs of LGK-PFX and CK were 0.744 ± 0.075 and 0.759 ± 0.071 (p = 0.385), respectively. The SIs of LGK-PFX and CK were 0.764 ± 0.081 and 0.780 ± 0.076 (p = 0.424), respectively. The GI75%, GI50%, and GI25% values of LGK-PFX and CK were 1.028 ± 0.123 and 2.439 ± 0.338 (p < 0.001), 3.169 ± 0.265 and 4.972 ± 0.852 (p < 0.001), and 8.650 ± 0.914 and 14.261 ± 2.476 (p < 0.001), respectively. Volumes of the brain tissue covered by 10 Gy and 12 Gy for LGK-PFX and CK (p < 0.001) exhibited a significant difference. CONCLUSIONS: LGK-PFX and CK exhibited similar dose conformity. LGK-PFX showed superior normal tissue sparing.


Assuntos
Malformações Arteriovenosas/radioterapia , Malformações Arteriovenosas/cirurgia , Encéfalo/efeitos da radiação , Encéfalo/cirurgia , Radiocirurgia/métodos , Dosagem Radioterapêutica , Humanos , Planejamento da Radioterapia Assistida por Computador
15.
J Appl Clin Med Phys ; 18(6): 114-122, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960724

RESUMO

In Gamma Knife forward treatment planning, normalization effect may be observed when multiple shots are used for treating large lesions. This effect can reduce the proportion of coverage of high-value isodose lines within targets. The aim of this study was to evaluate the performance of forward treatment planning techniques using the Leksell Gamma Knife for the normalization effect reduction. We adjusted the shot positions and weightings to optimize the dose distribution and reduce the overlap of high-value isodose lines from each shot, thereby mitigating the normalization effect during treatment planning. The new collimation system, Leksell Gamma Knife Perfexion, which contains eight movable sectors, provides an additional means to reduce the normalization effect by using composite shots. We propose different techniques in forward treatment planning that can reduce the normalization effect. Reducing the normalization effect increases the coverage proportion of higher isodose lines within targets, making the high-dose region within targets more uniform and increasing the mean dose to targets. Because of the increase in the mean dose to the target after reducing the normalization effect, we can set the prescribed marginal dose at a higher isodose level and reduce the maximum dose, thereby lowering the risk of complications.


Assuntos
Neoplasias Encefálicas/cirurgia , Neuroma Acústico/cirurgia , Planejamento de Assistência ao Paciente/normas , Radiocirurgia/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Algoritmos , Tronco Encefálico/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
16.
Neonatology ; : 1-10, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38797163

RESUMO

INTRODUCTION: Meconium aspiration syndrome (MAS) may cause severe pulmonary and neurologic injuries in affected infants after birth, leading to long-term adverse pulmonary or neurodevelopmental outcomes. METHODS: This retrospective population-based cohort study enrolled 1,554,069 mother-child pairs between 2004 and 2014. A total of 8,049 infants were in the MAS-affected group, whereas 1,546,020 were in the healthy control group. Children were followed up for at least 3 years. According to respiratory support, MAS was classified as mild, moderate, and severe. With the healthy control group as the reference, the associations between MAS severity and adverse pulmonary outcomes (hospital admission, intensive care unit (ICU) admission, length of hospital stay, or invasive ventilator support during admission related to pulmonary problem) or adverse neurodevelopmental outcomes (cerebral palsy, needs for rehabilitation, visual impairment, or hearing impairment) were accessed. RESULTS: MAS-affected infants had a higher risk of hospital and ICU admission and longer length of hospital stay, regardless of severity. Infants with severe MAS had a higher risk of invasive ventilator support during re-admission (odds ratio: 17.50, 95% confidence interval [CI]: 7.70-39.75, p < 0.001). Moderate (hazard ratio [HR]: 1.66, 95% CI: 1.30-2.13, p < 0.001) and severe (HR: 4.94, 95% CI: 4.94-7.11, p < 0.001) MAS groups had a higher risk of adverse neurodevelopmental outcome, and the statistical significance remained remarkable in severe MAS group after adjusting for covariates (adjusted HR: 2.28, 95% CI: 1.54-3.38, p < 0.001) Conclusions: Adverse pulmonary or neurodevelopmental outcomes could occur in MAS-affected infants at birth. Close monitoring and follow-up of MAS-affected infants are warranted.

17.
Nat Commun ; 15(1): 2170, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461153

RESUMO

All-polymer solar cells (all-PSCs) offer improved morphological and mechanical stability compared with those containing small-molecule-acceptors (SMAs). They can be processed with a broader range of conditions, making them desirable for printing techniques. In this study, we report a high-performance polymer acceptor design based on bithiazole linker (PY-BTz) that are on par with SMAs. We demonstrate that bithiazole induces a more coplanar and ordered conformation compared to bithiophene due to the synergistic effect of non-covalent backbone planarization and reduced steric encumbrances. As a result, PY-BTz shows a significantly higher efficiency of 16.4% in comparison to the polymer acceptors based on commonly used thiophene-based linkers (i.e., PY-2T, 9.8%). Detailed analyses reveal that this improvement is associated with enhanced conjugation along the backbone and closer interchain π-stacking, resulting in higher charge mobilities, suppressed charge recombination, and reduced energetic disorder. Remarkably, an efficiency of 14.7% is realized for all-PSCs that are solution-sheared in ambient conditions, which is among the highest for devices prepared under conditions relevant to scalable printing techniques. This work uncovers a strategy for promoting backbone conjugation and planarization in emerging polymer acceptors that can lead to superior all-PSCs.

18.
Biomimetics (Basel) ; 8(6)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37887598

RESUMO

It is expected that interconnected networks of autonomous vehicles, especially during peak traffic, will face congestion challenges. Moreover, the existing literature lacks discussions on integrating next-generation wireless communication technologies into connected vehicular networks. Hence, this paper introduces a tailored bandwidth management algorithm for streaming applications of autonomous vehicle passengers. It leverages cutting-edge 6G wireless technology to create a network with high-speed transmission and broad coverage, ensuring smooth streaming application performance. The key features of bandwidth allocation for diverse streaming applications in this work include bandwidth relay and pre-loading of video clips assisted by vehicle-to-vehicle communication. Through simulations, this research effectively showcases the algorithm's ability to fulfill the bandwidth needs of diverse streaming applications for autonomous vehicle passengers. Specifically, during periods of peak user bandwidth demand, it notably increases the bandwidth accessible for streaming applications. On average, users experience a substantial 55% improvement in the bandwidth they can access. This validation affirms the viability and promise of the proposed approach in efficiently managing the intricate complexities of bandwidth allocation issues for streaming services within the connected autonomous vehicular networks.

19.
Mol Plant Pathol ; 24(8): 973-988, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37158451

RESUMO

Zucchini yellow mosaic virus (ZYMV) seriously damages cucurbits worldwide. Control of ZYMV by cross-protection has been practised for decades, but selecting useful mild viruses is time-consuming and laborious. Most attenuated potyviruses used for cross-protection do not induce hypersensitive reaction (HR) in Chenopodium quinoa, a local lesion host Chenopodium quinoa. Here, severe ZYMV TW-TN3 tagged with green fluorescent protein (GFP), designated ZG, was used for nitrous acid mutagenesis. From three trials, 11 mutants were identified from fluorescent spots without HR in inoculated C. quinoa leaves. Five mutants caused attenuated symptoms in squash plants. The genomic sequences of these five mutants revealed that most of the nonsynonymous changes were located in the HC-Pro gene. The replacement of individual mutated HC-Pros in the ZG backbone and an RNA silencing suppression (RSS) assay indicated that each mutated HC-Pro is defective in RSS function and responsible for reduced virulence. Four mutants provided high degrees of protection (84%-100%) against severe virus TW-TN3 in zucchini squash plants, with ZG 4-10 being selected for removal of the GFP tag. After removal of the GFP gene, Z 4-10 induced symptoms similar to ZG 4-10 and still provided 100% protection against TW-TN3 in squash, thus is considered not a genetically engineered mutant. Therefore, using a GFP reporter to select non-HR mutants of ZYMV from C. quinoa leaves is an efficient way to obtain beneficial mild viruses for cross-protection. This novel approach is being applied to other potyviruses.


Assuntos
Cucurbita , Potyvirus , Ácido Nitroso , Potyvirus/genética , Mutagênese , Interferência de RNA
20.
Mol Plant Pathol ; 23(7): 947-965, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35285990

RESUMO

Control of plant viruses by cross-protection is limited by the availability of effective protective strains. Incorporation of an NIa-protease processing site in the extreme N-terminal region of the helper component protease (HC-Pro) of turnip mosaic virus (TuMV) resulted in a mutant virus TuHND I that induced highly attenuated symptoms. Recombination analysis verified that two variations, F7I mutation and amino acid 7-upstream-deletion, in HC-Pro co-determined TuHND I attenuation. TuHND I provided complete protection to Nicotiana benthamiana and Brassica campestris subsp. chinensis plants against infection by the severe parental strain. Aphid transmission tests revealed that TuHND I was not aphid-transmissible. An RNA silencing suppression (RSS) assay by agroinfiltration suggested the RSS-defective nature of the mutant HC-Pro. In the context (amino acids 3-17) encompassing the two variations of HC-Pro, we uncovered an FWKG-α-helix 1 (αH1) element that influenced the functions of aphid transmission and RSS, whose motifs were located far downstream. We further demonstrated that HC-Pro F7 was a critical residue on αH1 for HC-Pro functions and that reinstating αH1 in the RSS-defective HC-Pro of TuHND I restored the protein's RSS function. Yeast two-hybrid and bimolecular fluorescence complementation assays indicated the FWKG-αH1 element as an integral part of the HC-Pro self-interaction domain. The possibility of regulation of the mechanistically independent functions of RSS and aphid transmission by the FWKG-αH1 element is discussed. Extension of TuMV HC-Pro FWKG-αH1 variations to another potyvirus, zucchini yellow mosaic virus, also generated nonaphid-transmissible cross-protective mutant viruses. Hence, the modification of the FWKG-αH1 element can generate effective attenuated viruses for the control of potyviruses by cross-protection.


Assuntos
Afídeos , Potyvirus , Animais , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Doenças das Plantas/prevenção & controle , Potyvirus/fisiologia , Proteínas Virais
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