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1.
J Integr Plant Biol ; 66(1): 17-19, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38078380

RESUMO

A sample delivery method, modified from cut-dip-budding, uses explants with robust shoot regeneration ability, enabling transformation and gene editing in medicinal plants, bypassing tissue culture and hairy root formation. This method has potential for applications across a wide range of plant species.


Assuntos
Edição de Genes , Plantas Medicinais , Edição de Genes/métodos , Plantas Medicinais/genética , Transformação Genética , Plantas Geneticamente Modificadas/genética
2.
J Integr Plant Biol ; 66(4): 642-644, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38390811

RESUMO

Knockout of the soybean (Glycine max) betaine aldehyde dehydrogenase genes GmBADH1 and GmBADH2 using CRISPR/Cas12i3 enhances the aroma of soybeans. Soy milk made from the gmbadh1/2 double mutant seeds exhibits a much stronger aroma, which consumers prefer; this mutant has potential for enhancing quality in soy-based products.


Assuntos
Glycine max , Leite de Soja , Glycine max/genética , Odorantes/análise , Melhoramento Vegetal
3.
J Integr Plant Biol ; 66(6): 1148-1157, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38597776

RESUMO

Yield improvement has long been an important task for soybean breeding in the world in order to meet the increasing demand for food and animal feed. miR396 genes have been shown to negatively regulate grain size in rice, but whether miR396 family members may function in a similar manner in soybean is unknown. Here, we generated eight soybean mutants harboring different combinations of homozygous mutations in the six soybean miR396 genes through genome editing with clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated nuclease (Cas)12SF01 in the elite soybean cultivar Zhonghuang 302 (ZH302). Four triple mutants (mir396aci, mir396acd, mir396adf, and mir396cdf), two quadruple mutants (mir396abcd and mir396acfi), and two quintuple mutants (mir396abcdf and mir396bcdfi) were characterized. We found that plants of all the mir396 mutants produced larger seeds compared to ZH302 plants. Field tests showed that mir396adf and mir396cdf plants have significantly increased yield in growth zones with relatively high latitude which are suited for ZH302 and moderately increased yield in lower latitude. In contrast, mir396abcdf and mir396bcdfi plants have increased plant height and decreased yield in growth zones with relatively high latitude due to lodging issues, but they are suited for low latitude growth zones with increased yield without lodging problems. Taken together, our study demonstrated that loss-of-function of miR396 genes leads to significantly enlarged seed size and increased yield in soybean, providing valuable germplasms for breeding high-yield soybean.


Assuntos
Glycine max , MicroRNAs , Sementes , Glycine max/genética , Glycine max/crescimento & desenvolvimento , MicroRNAs/genética , MicroRNAs/metabolismo , Sementes/genética , Mutação/genética , Genes de Plantas , Edição de Genes , Técnicas de Inativação de Genes
4.
World Wide Web ; 26(2): 539-559, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35528264

RESUMO

Developmental dysplasia of the hip (DDH) is one of the most common diseases in children. Due to the experience-requiring medical image analysis work, online automatic diagnosis of DDH has intrigued the researchers. Traditional implementation of online diagnosis faces challenges with reliability and interpretability. In this paper, we establish an online diagnosis tool based on a multi-task hourglass network, which can accurately extract landmarks to detect the extent of hip dislocation and predict the age of the femoral head. Our method utilizes a multi-task hourglass network, which trains an encoder-decoder network to regress the landmarks and predict the developmental age for online DDH diagnosis. With the support of precise image analysis and fast GPU computing, our method can help overcome the shortage of medical resources and enable telehealth for DDH diagnosis. Applying this approach to a dataset of DDH X-ray images, we demonstrate 4.64 mean pixel error of landmark detection compared to the results of human experts. Moreover, we can improve the accuracy of the age prediction of femoral heads to 89%. Our online automatic diagnosis system has provided service to 112 patients, and the results demonstrate the effectiveness of our method.

5.
Angew Chem Int Ed Engl ; 61(7): e202114080, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-34882934

RESUMO

Cu2 O microparticles with controllable crystal planes and relatively high stability have been recognized as a good platform to understand the mechanism of the electrocatalytic CO2 reduction reaction (CO2 RR). Herein, we demonstrate that the in situ generated Cu2 O/Cu interface plays a key role in determining the selectivity of methane formation, rather than the initial crystal plane of the reconstructed Cu2 O microparticles. Experimental results indicate that the methane evolution is dominated on all three different crystal planes with similar Tafel slopes and long-term stabilities. Density functional theory (DFT) calculations further reveal that *CO is protonated via a similar bridge configuration at the Cu2 O/Cu interface, regardless of the initial crystal planes of Cu2 O. The Gibbs free energy changes (ΔG) of *CHO on different reconstructed Cu2 O planes are close and more negative than that of *OCCOH, indicating the methane formation is more favorable than ethylene on all Cu2 O crystal planes.

7.
Opt Express ; 27(4): 5598-5609, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876159

RESUMO

For deep-sea natural gas hydrate exploration, highly sensitive detection of the dissolved gas in seawater near the seabed is significant because it requires the sensor system to be small in size, low in power consumption, and high in sensitivity. A mid-infrared sensor system was developed to detect dissolved carbon dioxide (CO2) in sea-water, while employing a 4319 nm continuous-wave interband cascade laser (ICL) and a multi-pass gas cell (MPGC) with a 29.8 m optical path length. A compact rectilinear optical structure was proposed by using the free-space-emitting ICL and tunable laser absorption spectroscopy (TLAS). This leads to a minimized sensor size and a simple optical alignment for deep-sea operation. A strong CO2 absorption line, located at 2315.19 cm-1 and a weak 2315.28 cm-1 line and at a low pressure of 40 Torr, was targeted for low- and high-concentration CO2 detection within a concentration range of 0-1000 parts per billion by volume (ppbv) and 0-40 parts per million by volume (ppmv), respectively. The limit of detection (LoD) was assessed to be 0.72 ppbv at an averaging time of 2 s, and the response time was measured to be ~30 s at a flow rate of ~180 standard cubic centimeters per minute (sccm). Deployment of the CO2 sensor combined with a gas-liquid separator was carried out for the CO2 detection in the gas extracted from water, which validated the reported sensor system's potential application for deep-sea natural gas hydrate exploration.

8.
Inorg Chem ; 58(9): 5423-5427, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31007026

RESUMO

Producing ammonia (NH3) by electrocatalytic N2 fixation is a promising and environmentally friendly strategy, in comparison to the Haber-Bosch process with high consumption of energy and CO2 emissions. Because of the extremely high bond energy, it is indispensable to explore valid catalysts to activate the triple bond. In this paper, Cr-doped CeO2 nanorods are developed to serve as non-noble-metal electrocatalysts for an electrocatalytic N2 reduction reaction. Introducing Cr into the catalyst leads to an increase of the oxygen vacancies. In a 0.1 M Na2SO4 solution, the Cr0.1CeO2 nanorods achieve a high Faradaic efficiency (3.84%) and a large NH3 yield (16.82 µg h-1 mgcat.-1) at -0.7 V versus reversible hydrogen electrode. The Cr0.1CeO2 nanorods also exhibit high stability during the reaction.

10.
Plant Physiol ; 173(1): 206-218, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27799422

RESUMO

Programmed cell death (PCD)-triggered degradation of plant tapetum is essential for microspore development and pollen coat formation; however, little is known about the cellular mechanism regulating tapetal PCD Here, we demonstrate that Rab7-mediated vacuolar transport of tapetum degradation-related cysteine proteases is crucial for tapetal PCD and pollen development in Arabidopsis (Arabidopsis thaliana), with the following evidence: (1) The monensin sensitivity1 (mon1) mutants, which are defective in Rab7 activation, showed impaired male fertility due to a combined defect in both tapetum and male gametophyte development. (2) In anthers, MON1 showed preferential high level expression in tapetal cell layers and pollen. (3) The mon1 mutants exhibited delayed tapetum degeneration and tapetal PCD, resulting in abnormal pollen coat formation and decreased male fertility. (4) MON1/CALCIUM CAFFEINE ZINC SENSITIVITY1 (CCZ1)-mediated Rab7 activation was indispensable for vacuolar trafficking of tapetum degradation-related cysteine proteases, supporting that PCD-triggered tapetum degeneration requires Rab7-mediated vacuolar trafficking of these cysteine proteases. (5) MON1 mutations also resulted in defective pollen germination and tube growth. Taken together, tapetal PCD and pollen development require successful MON1/CCZ1-mediated vacuolar transport in Arabidopsis.


Assuntos
Apoptose , Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Pólen/citologia , Pólen/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Cisteína Proteases/metabolismo , Ativação Enzimática , Genes Dominantes , Germinação , Modelos Biológicos , Mutação/genética , Infertilidade das Plantas/genética , Folhas de Planta/metabolismo , Pólen/ultraestrutura , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/metabolismo , Protoplastos/metabolismo , Vacúolos/metabolismo , proteínas de unión al GTP Rab7
11.
Nanotechnology ; 29(22): 225705, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29498626

RESUMO

The adhesion and friction between two Al2O3 nanowires (NWs) was characterized by the use of optical microscopy based nanomanipulation, with which peeling, shearing and sliding was performed. The elastically deformed shape of the NWs during peeling and shearing was used to calculate the adhesion and frictional forces; force sensing was not required. The obtained adhesion stress between two Al2O3 NWs varied from 0.14 to 0.25 MPa, lower than that observed for carbon nanotube junctions, and was attributed to van der Waals attraction. Stick-slip was observed during the shearing and sliding of two NWs, and was the consequence of discrete contact between surface asperities. The obtained static and kinetic frictional stresses varied from 0.7 to 1.3 MPa and 0.4 to 0.8 MPa, respectively; significantly greater than the obtained adhesion stress.

12.
BMC Plant Biol ; 17(1): 76, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28427341

RESUMO

BACKGROUND: Hybrid vigor is highly valued in the agricultural industry. Male sterility is an important trait for crop breeding. Pollen development is under strict control of both gametophytic and sporophytic factors, and defects in this process can result in male sterility. Both in the dicot Arabidopsis and in the moncot rice, proper timing of programmed cell death (PCD) in the tapetum ensures pollen development. Dynamic ROS levels have been reported to control tapetal PCD, and thus pollen development, in Arabidopsis and rice. However, it was unclear whether it is evolutionarily conserved, as only those two distantly related species were studied. RESULTS: Here, we performed histological analyses of anther development of two economically important dicot species, tobacco and tomato. We identified the same ROS amplitude during anther development in these two species and found that dynamic ROS levels correlate with the initiation and progression of tapetal PCD. We further showed that manipulating ROS levels during anther development severely impaired pollen development, resulting in partial male sterility. Finally, real-time quantitative PCR showed that several tobacco and tomato RBOHs, encoding NADPH oxidases, are preferentially expressed in anthers. CONCLUSION: This study demonstrated evolutionarily conserved ROS amplitude during anther development by examining two commercially important crop species in the Solanaceae. Manipulating ROS amplitude through genetic interference of RBOHs therefore may provide a practical way to generate male sterile plants.


Assuntos
Nicotiana/citologia , Células Vegetais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Solanum lycopersicum/citologia , Morte Celular , Flores/crescimento & desenvolvimento , Flores/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Nicotiana/genética , Nicotiana/metabolismo
13.
Plant Cell ; 26(5): 2007-2023, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24808050

RESUMO

Male sterility in angiosperms has wide applications in agriculture, particularly in hybrid crop breeding and gene flow control. Microspores develop adjacent to the tapetum, a layer of cells that provides nutrients for pollen development and materials for pollen wall formation. Proper pollen development requires programmed cell death (PCD) of the tapetum, which requires transcriptional cascades and proteolytic enzymes. Reactive oxygen species (ROS) also affect tapetal PCD, and failures in ROS scavenging cause male sterility. However, many aspects of tapetal PCD remain unclear, including what sources generate ROS, whether ROS production has a temporal pattern, and how the ROS-producing system interacts with the tapetal transcriptional network. We report here that stage-specific expression of NADPH oxidases in the Arabidopsis thaliana tapetum contributes to a temporal peak of ROS production. Genetic interference with the temporal ROS pattern, by manipulating RESPIRATORY-BURST OXIDASE HOMOLOG (RBOH) genes, affected the timing of tapetal PCD and resulted in aborted male gametophytes. We further show that the tapetal transcriptional network regulates RBOH expression, indicating that the temporal pattern of ROS production intimately connects to other signaling pathways regulated by the tapetal transcriptional network to ensure the proper timing of tapetal PCD.

14.
Nanotechnology ; 27(6): 065709, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26762859

RESUMO

SiC nanowires were manipulated under an optic microscope to investigate the nanoscale friction between nanowires and a flat substrate. The deflection of the nanowires was modeled as that of an Euler-Bernoulli beam subjected to a uniformly distributed load. A simple formula was developed to calculate the kinetic friction from the normalized deflections at the two ends of a nanowire. The frictional force per unit area determined ranges from 0.18-0.51 MPa. Both experimental and simulated results demonstrated that the proposed approach was reliable. The results were also compared with those estimated using an energy-conservation model, which produced a frictional force ranging from 0.21-0.62 MPa. The results obtained from the two different methods are in excellent agreement.

15.
Chem Commun (Camb) ; 60(5): 542-545, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38093711

RESUMO

A hydrophobic cationic-ionomer layer of quaternary ammonium poly(N-methyl-piperidine-co-p-terphenyl) and PTFE is presented to enhance the CO2 electroreduction in a zero-gap membrane electrode assembly (MEA) electrolyzer under acidic and low alkali ion concentration conditions. The modified MEA achieved a maximum CO faradaic efficiency of 95.6% at 100 mA cm-2.

16.
Psychiatry Res ; 332: 115672, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38150811

RESUMO

Cognitive impairments are a core symptom of schizophrenia. Although low-intensity repetitive transcranial magnetic stimulation (rTMS) also has cognitive improving effect like the commonly used high-intensity rTMS, it has not been applied in schizophrenia yet. To fill this gap, inpatients with schizophrenia were randomized to receive 20 sessions of daily adjunctive active low-intensity rTMS in 4 weeks, or sham treatment. At baseline, 4 weeks, and 6 months, the Positive and Negative Syndrome Scale (PANSS) was used to assess psychotic symptom severity, while the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Stroop Color and Word Test (SCWT) were used to assess cognitive functions. Compared to the sixty-nine patients receiving sham treatment, those fifty-nine patients receiving active rTMS performed better in all cognitive domains at post-treatment with small to large effect sizes. This superiority of active rTMS over sham treatment remained significant at 6-month follow-up, with small to large effect sizes, except for visuospatial function and delayed memory. The reduction in PANSS scores were not correlated with cognitive improvements. Our findings provide evidence for using low-intensity rTMS to ameliorate cognitive impairments in schizophrenia. More research are needed to determine the optimal intensity for each domain of cognitive functions.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/complicações , Esquizofrenia/terapia , Esquizofrenia/diagnóstico , Estimulação Magnética Transcraniana , Resultado do Tratamento , Córtex Pré-Frontal , Método Duplo-Cego , Cognição
17.
Innovation (Camb) ; 5(2): 100564, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38379787

RESUMO

The type V-I CRISPR-Cas system is becoming increasingly more attractive for genome editing. However, natural nucleases of this system often exhibit low efficiency, limiting their application. Here, we used structure-guided rational design and protein engineering to optimize an uncharacterized Cas12i nuclease, Cas12i3. As a result, we developed Cas-SF01, a Cas12i3 variant that exhibits significantly improved gene editing activity in mammalian cells. Cas-SF01 shows comparable or superior editing performance compared to SpCas9 and other Cas12 nucleases. Compared to natural Cas12i3, Cas-SF01 has an expanded PAM range and effectively recognizes NTTN and noncanonical NATN and TTVN PAMs. In addition, we identified an amino acid substitution, D876R, that markedly reduced the off-target effect while maintaining high on-target activity, leading to the development of Cas-SF01HiFi (high-fidelity Cas-SF01). Finally, we show that Cas-SF01 has high gene editing activities in mice and plants. Our results suggest that Cas-SF01 can serve as a robust gene editing platform with high efficiency and specificity for genome editing applications in various organisms.

18.
Health Inf Sci Syst ; 11(1): 26, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37325196

RESUMO

Semi-supervised learning (SSL) has attracted increasing attention in medical image segmentation, where the mainstream usually explores perturbation-based consistency as a regularization to leverage unlabelled data. However, unlike directly optimizing segmentation task objectives, consistency regularization is a compromise by incorporating invariance towards perturbations, and inevitably suffers from noise in self-predicted targets. The above issues result in a knowledge gap between supervised guidance and unsupervised regularization. To bridge the knowledge gap, this work proposes a meta-based semi-supervised segmentation framework with the exploitation of label hierarchy. Two main prominent components named Divide and Generalize, and Label Hierarchy, are built in this work. Concretely, rather than merging all knowledge indiscriminately, we dynamically divide consistency regularization from supervised guidance as different domains. Then, a domain generalization technique is introduced with a meta-based optimization objective which ensures the update on supervised guidance should generalize to the consistency regularization, thereby bridging the knowledge gap. Furthermore, to alleviate the negative impact of noise in self-predicted targets, we propose to distill the noisy pixel-level consistency by exploiting label hierarchy and extracting hierarchical consistencies. Comprehensive experiments on two public medical segmentation benchmarks demonstrate the superiority of our framework to other semi-supervised segmentation methods, with new state-of-the-art results.

19.
IEEE Trans Pattern Anal Mach Intell ; 45(6): 7123-7141, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36417745

RESUMO

Scene text spotting is of great importance to the computer vision community due to its wide variety of applications. Recent methods attempt to introduce linguistic knowledge for challenging recognition rather than pure visual classification. However, how to effectively model the linguistic rules in end-to-end deep networks remains a research challenge. In this paper, we argue that the limited capacity of language models comes from 1) implicit language modeling; 2) unidirectional feature representation; and 3) language model with noise input. Correspondingly, we propose an autonomous, bidirectional and iterative ABINet++ for scene text spotting. First, the autonomous suggests enforcing explicitly language modeling by decoupling the recognizer into vision model and language model and blocking gradient flow between both models. Second, a novel bidirectional cloze network (BCN) as the language model is proposed based on bidirectional feature representation. Third, we propose an execution manner of iterative correction for the language model which can effectively alleviate the impact of noise input. Additionally, based on an ensemble of the iterative predictions, a self-training method is developed which can learn from unlabeled images effectively. Finally, to polish ABINet++ in long text recognition, we propose to aggregate horizontal features by embedding Transformer units inside a U-Net, and design a position and content attention module which integrates character order and content to attend to character features precisely. ABINet++ achieves state-of-the-art performance on both scene text recognition and scene text spotting benchmarks, which consistently demonstrates the superiority of our method in various environments especially on low-quality images. Besides, extensive experiments including in English and Chinese also prove that, a text spotter that incorporates our language modeling method can significantly improve its performance both in accuracy and speed compared with commonly used attention-based recognizers. Code is available at https://github.com/FangShancheng/ABINet-PP.

20.
IEEE Trans Image Process ; 32: 4567-4580, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37556339

RESUMO

As a crucial application in privacy protection, scene text removal (STR) has received amounts of attention in recent years. However, existing approaches coarsely erasing texts from images ignore two important properties: the background texture integrity (BI) and the text erasure exhaustivity (EE). These two properties directly determine the erasure performance, and how to maintain them in a single network is the core problem for STR task. In this paper, we attribute the lack of BI and EE properties to the implicit erasure guidance and imbalanced multi-stage erasure respectively. To improve these two properties, we propose a new ProgrEssively Region-based scene Text eraser (PERT). There are three key contributions in our study. First, a novel explicit erasure guidance is proposed to enhance the BI property. Different from implicit erasure guidance modifying all the pixels in the entire image, our explicit one accurately performs stroke-level modification with only bounding-box level annotations. Second, a new balanced multi-stage erasure is constructed to improve the EE property. By balancing the learning difficulty and network structure among progressive stages, each stage takes an equal step towards the text-erased image to ensure the erasure exhaustivity. Third, we propose two new evaluation metrics called BI-metric and EE-metric, which make up the shortcomings of current evaluation tools in analyzing BI and EE properties. Compared with previous methods, PERT outperforms them by a large margin in both BI-metric ( ↑ 6.13 %) and EE-metric ( ↑ 1.9 %), obtaining SOTA results with high speed (71 FPS) and at least 25% lower parameter complexity. Code will be available at https://github.com/wangyuxin87/PERT.

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