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1.
Opt Express ; 31(12): 20286-20305, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381427

RESUMEN

Artificial intelligence (AI) has been widely used in various fields of physics and engineering in recent decades. In this work, we introduce model-based reinforcement learning (MBRL), which is an important branch of machine learning in the AI domain, to the broadband frequency-swept laser control for frequency modulated continuous wave (FMCW) light detection and ranging (LiDAR). With the concern of the direct interaction between the optical system and the MBRL agent, we establish the frequency measurement system model on the basis of the experimental data and the nonlinearity property of the system. In light of the difficulty of this challenging high-dimensional control task, we propose a twin critic network on the basis of the Actor-Critic structure to better learn the complex dynamic characteristics of the frequency-swept process. Furthermore, the proposed MBRL structure would stabilize the optimization process greatly. In the training process of the neural network, we apply a delaying strategy to the policy update and introduce a smoothing regularization strategy to the target policy to further enhance the network stability. With the well-trained control policy, the agent generates the excellent and regularly updated modulation signals to control the laser chirp precisely and an excellent detection resolution is obtained eventually. Our proposed work demonstrates that the integration of data-driven reinforcement learning (RL) and optical system control gives an opportunity to reduce the system complexity and accelerate the investigation and optimization of control systems.

2.
Int J Mol Sci ; 24(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36982803

RESUMEN

Female mice can discriminate the urinary odors of male mice due to their olfactory acuity. Parasitic infection or subclinical infection can decrease the odor attractiveness of male mice and finally lead to aversion or avoidance responses in odor selection for female mice. Trichinella spiralis is a kind of tissue-parasitizing nematode that causes trichinellosis, a zoonotic parasitic disease that spreads throughout the world. However, the reproductive injury caused by Trichinella spiralis infection was not fully revealed. In this study, we explored the effect of Trichinella spiralis infection on the reproductive capacity in ICR/CD-1 male mice. We identified eight volatile compounds in urine by GC-MS analysis, and the results indicated that the contents of dimethyl sulfone, Z-7-tetradecen-1-ol, 6-Hydroxy-6-methyl-3-heptanone and (S)-2-sec-butyl-4,5-dihydrothiazole were significantly downregulated after parasitic infection, which might lead to the reduction of attractiveness of male mice urine to females. On the other hand, parasitic infection decreased sperm quality and downregulated the expression levels of Herc4, Ipo11, and Mrto4, and these genes were strongly related to spermatogenesis. In summary, this study revealed that the reproductive injury caused by Trichinella spiralis infection in ICR/CD-1 male mice could be associated with a decrease in urine pheromone content and sperm quality.


Asunto(s)
Trichinella spiralis , Triquinelosis , Masculino , Femenino , Ratones , Animales , Trichinella spiralis/genética , Ratones Endogámicos ICR , Feromonas , Semen , Triquinelosis/parasitología , Zoonosis , Espermatozoides
3.
Opt Express ; 30(12): 20647-20658, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224804

RESUMEN

The prevalence of machine learning (ML) opens up new directions for plenty of scientific fields. The development of optics technologies also benefits from it. However, due to the complex properties of nonlinear and dynamic optical systems, optical system control with ML is still in its infancy. In this manuscript, to demonstrate the feasibility of optical system control using reinforcement learning (RL), i.e., a branch of ML, we solve the linearization problem in the frequency modulated continuous wave (FMCW) generation with the model-based RL method. The experiment results indicate an excellent improvement in the linearity of the generated FMCW, showing a sharp peak in the frequency spectrum. We confirm that the RL method learns the implicit physical characteristics very well and accomplishes the goal of the linear FMCW generation effectively, indicating that the marriage of ML and optics systems could have the potential to open a new era for the development of optical system control.

4.
Int J Mol Sci ; 23(22)2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36430336

RESUMEN

Echinochloa crus-galli var. crus-galli, E. crus-galli var. zelayensis, and E. glabrescens, morphologically similar at the seedling stage, are the most pernicious barnyard grass species in paddy fields worldwide. Chloroplast (cp) genomes could be conducive to their identification. In this study, we assembled the complete cp genome sequences of Echinochloa crus-galli var. crus-galli (139,856 bp), E. crus-galli var. zelayensis (139,874 bp), and E. glabrescens (139,874 bp), which exhibited a typical circular tetramerous structure, large and small single-copy regions, and a pair of inverted repeats. In Echinochloa crus-galli var. crus-galli, there were 136 simple sequence (SSRs) and 62 long (LRs) repeats, and in the other two species, 139 SSRs and 68 LRs. Each cp genome contains 92 protein-encoding genes. In Echinochloa crus-galli var. crus-galli and E. glabrescens, 321 and 1 single-nucleotide polymorphisms were detected compared to Echinochloa crus-galli var. zelayensis. IR expansion and contraction revealed small differences between the three species. The phylogenetic tree based on cp genomes demonstrated the phylogenetic relationship between ten barnyard grass species and other common Gramineae plants, showing new genetic relationships of the genus Echinochloa. This study provides valuable information on cp genomes, useful for identifying and classifying the genus Echinochloa and studying its phylogenetic relationships and evolution.


Asunto(s)
Echinochloa , Genoma del Cloroplasto , Echinochloa/genética , Filogenia
5.
Arch Microbiol ; 204(1): 56, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34936038

RESUMEN

The insects of Ostrinia furnacalis and Helicoverpa armigera are the two main pests that affect maize growth, which significantly decrease the yield. Plants induce various immune-related pathways to antagonize insect feeding during insect-plant interactions. Moreover, different insect elicitors or effectors participate in the interactions via releasing into plants. While there are many bacteria during insect regurgitation, their roles in insect-plant interaction are unknown. In this study, four bacterial strains were isolated from regurgitation fluid of O. furnacalis and H. armigera, and their cultures were inoculated on maize leaves for response analysis. All the four bacterial strains altered gene expression profiles in maize, and these altered expression profiles included phytohormones, secondary metabolic pathways, transcription factors, MAPK, and plant-pathogen interaction-related genes. A total of 210 genes, such as WRKY54, WRKY62, PIF5, argonaute 1, Xa21, NRR, ubiquitin-proteasome system genes, were co-changed in response to bacterial inoculation. These changes were similar with maize gene profile changes after insect feeding. Symbiotic insect bacteria participate in insect-plant interactions by changing maize gene expression profiles, which might be used to develop anti-pest microbial agents by activating plant defense system with identified microbes. In future, understanding the roles of symbiotic insect bacteria on plant-insect interaction might provide a promising and novel strategy for pest biocontrol using microbes.


Asunto(s)
Mariposas Nocturnas , Zea mays , Animales , Bacterias , Larva , Mariposas Nocturnas/genética , Transcriptoma , Zea mays/genética
6.
Exp Cell Res ; 395(2): 112220, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32777225

RESUMEN

Capn4, a small regulatory subunit of the calpain proteolytic system, functions as a potential tumor promoter in several cancers. However, the biological functions and molecular mechanisms of Capn4 in gastric cancer (GC) remain poorly understood. In the current study, we found that upregulation of Capn4 was detected frequently in GC tissues, and was associated with significantly worse survival among the GC patients. Multivariate analyses revealed that abundance of Capn4 was an independent predictive marker for the poor prognosis of GC. Further, Capn4 knockdown notably suppressed GC invasion and metastasis in vitro. Consistently, a xenograft assay showed that silencing of Capn4 in GC cells suppressed their dissemination to lung tissue in vivo. Moreover, our results indicated that Capn4 promotes gastric cancer metastasis by increasing MMP9 expression, and demonstrated that MMP9 is crucial for the pro-metastasis role of Capn4 in GC cells. Further investigation revealed that Capn4 regulated MMP9 expression via activation of Wnt/ß-catenin signaling pathway. Mechanistically, we found that Capn4 can decreased ß-catenin ubiquitination to enhance the protein stability of ß-catenin in GC cells. Collectively, Capn4 has a central role in gastric cancer metastasis, which could be a potential diagnostic and therapeutic target for GC.


Asunto(s)
Calpaína/metabolismo , Metástasis de la Neoplasia/patología , Neoplasias Gástricas/patología , Vía de Señalización Wnt/fisiología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Metaloproteinasa 9 de la Matriz/metabolismo , Neoplasias Gástricas/metabolismo , Regulación hacia Arriba
7.
Arch Insect Biochem Physiol ; 107(4): e21829, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34191347

RESUMEN

The olfactory system of insects facilitates their search for host and mates, hence it plays an essential role for insect survival and reproduction. Insects recognize odor substances through olfactory neurons and olfactory genes. Previous studies showed that there are significant sex-specific differences in how insects identify odorant substances, especially sex pheromones. However, whether the sex-specific recognition of odorant substances is caused by differences in the expression of olfaction-related genes between males and females remains unclear. To clarify this problem, the whole transcriptome sequence of the adult Helicoverpa assulta, an important agricultural pest of tobacco and other Solanaceae plants, was obtained using Pacbio sequencing. RNA-seq analysis showed that there were 27 odorant binding proteins (OBPs), 24 chemosensory proteins, 4 pheromone-binding proteins (PBPs), 68 odorant receptors and 2 sensory neuron membrane proteins (SNMPs) genes, that were expressed in the antennae of male and female H. assulta. Females had significantly higher expression of General odorant-binding protein 1-like, OBP, OBP3, PBP3 and SNMP1 than males, while males had significantly higher expression of GOBP1, OBP7, OBP13, PBP2 and SNMP2. These results improve our understanding of mate search and host differentiation in H. assulta.


Asunto(s)
Antenas de Artrópodos/metabolismo , Mariposas Nocturnas/metabolismo , Caracteres Sexuales , Olfato/genética , Transcriptoma , Animales , Femenino , Masculino , Mariposas Nocturnas/genética
8.
Arch Virol ; 165(4): 989-991, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32170393

RESUMEN

This work identified a novel rhabdo-like virus in a Chinese black cutworm (Agrotis ipsilon), which we tentatively named "Agrotis ipsilon virus" (AIpsV). The complete genome of AIpsV is 15,454 nucleotides in length and contains seven open reading frames, collectively encoding more than 160 amino acids. The AIpsV genome is predicted to encode three structural proteins, nucleoprotein (N), glycoprotein (G), and large polymerase protein (L), and four unknown proteins. Phylogenetic analysis revealed that the AIpsV clusters with Wuhan ant virus and Hubei rhabdo-like virus 1 within the rhabdo-like virus clade. The level of expression of AIpsV genes was found to be higher in the pupal and adult stages than in the egg and larval stages.


Asunto(s)
Genoma Viral , Virus de Insectos/genética , Mariposas Nocturnas/virología , Animales , Secuencia de Bases , Virus de Insectos/clasificación , Virus de Insectos/aislamiento & purificación , Larva/crecimiento & desarrollo , Larva/virología , Mariposas Nocturnas/crecimiento & desarrollo , Sistemas de Lectura Abierta , Filogenia , Proteínas Virales/genética , Secuenciación Completa del Genoma
9.
J Insect Sci ; 19(2)2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30865781

RESUMEN

Holotrichia parallela damages seriously on peanut (Arachis hypogaea) pods. Elucidation of its flight and walking performance in the presence of different plants may provide an insight in its host selection process and an explanation to its strong olfactory preference to an attractive nonhost, castor bean (Ricinus communis). We determined the relationships among flight performance, mate choice, and body weight of H. parallela beetles, and then investigated their flight and walking patterns in the presence of known hosts and attractive nonhost plants using a flight mill and a locomotion compensator, respectively. Body weights were not related to mating success, regardless of sex. The flight proportion of selected females drastically decreased compared with nonselected females, nonselected males, and selected males. Within mated males, heavier individuals exhibited poorer flight performance than lighter ones. In flight bioassay, peanut showed an arrestment effect on virgin females. For walking activity factors (distance, time, and speed), the host plants velvetleaf (Abutilon theophrasti) and Siberian elm (Ulmus pumila) elicited the strongest responses in females and males, respectively. Interestingly, the most preferred adult host, Siberian elm, and the nonhost, castor bean, elicited the highest values of two orientation factors (orientation and upwind length) in females. The chemical similarity hypothesis, which states that feeding or oviposition of insects mistakenly on nonhost can be traced to their chemical similarity to actual hosts, could explain the attraction of H. parallela to castor bean.


Asunto(s)
Peso Corporal , Escarabajos/fisiología , Vuelo Animal , Herbivoria , Preferencia en el Apareamiento Animal , Animales , Femenino , Magnoliopsida , Masculino , Odorantes , Factores Sexuales , Caminata
10.
J Chem Ecol ; 44(10): 965-974, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30116996

RESUMEN

The castor bean, Ricinus communis L., is a non-host plant for the large black chafer, Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae). In laboratory bioassays we found that this plant was no less attractive than the main host plant (peanut, Arachis hypogaea) and three food plant species: velvetleaf (Abutilon theophrasti), the glossy privet (Ligustrum lucidum), and the Siberian elm (Ulmus pumila). In field trapping experiments a Soxhlet extract of castor bean leaves caught more beetles than the optimal sex lure blend [(R)-(-)-linalool and (L)-isoleucine methyl ester blended in a ratio of 1:4], compared at equal doses (500 µl), and laboratory bioassays indicated that a castor bean plant could enhance the attractiveness of different blend ratios of sex lures. Olfactometer bioassays showed that males prefer volatiles emitted from different combinations of castor bean plant extracts and a signaling female over a female alone. In the presence of castor bean plants copulation rates of H. parallela were highest among all test environments both in laboratory bioassays (60%) and in field tests (70%). This study, combined with our previous observation of the feeding behavior of H. parallela adults on castor bean leaves, suggests that castor bean plants may provide an attractive but risky mating site for H. parallela beetles. The enhancement of male mate-location and copulation rate in the presence of castor bean plants can balance its paralytic effects on H. parallela after intake of potential toxins contained in its leaves.


Asunto(s)
Escarabajos/efectos de los fármacos , Ricinus communis/metabolismo , Conducta Sexual Animal/efectos de los fármacos , Animales , Femenino , Masculino , Riesgo , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/farmacología
11.
Appl Opt ; 57(24): 6976-6981, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30129591

RESUMEN

Aimed at a high-performance biosensor for sensing biological molecules quickly and accurately, a novel nonuniform photonic crystal waveguide (NUPhCW) with a feedback loop is systematically investigated based on the mode-splitting effect. Thanks to the careful design of the nonuniform holes of NUPhCW with a feedback loop, the Autler-Townes splitting occurs in our device, and the spacing of two splitting resonance modes changes with the environmental refractive index, which is beneficial for achieving biosensing scenarios. Further, this integrated structure allows for self-referencing detection for immunity against environmental noise. Sensitivity of the NUPhCW is achieved at ∼117 nm/RIU, which is 2.6 times more than that of the common microring resonator, indicating that our proposed device structure would be promising for high-quality optical label-free sensing.


Asunto(s)
Técnicas Biosensibles/instrumentación , Óptica y Fotónica/métodos , Refractometría/instrumentación , Diseño de Equipo , Fotones
12.
Chemistry ; 23(11): 2610-2618, 2017 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-28000323

RESUMEN

A flexible and freestanding supercapacitor electrode with a N,P-co-doped carbon nanofiber network (N,P-CNFs)/graphene (GN) composite loaded on bacterial cellulose (BC) is first designed and fabricated in a simple, low-cost, and effective approach. The porous structure and excellent mechanical properties make the BC paper an ideal substrate that shows a large areal mass of 8 mg cm-2 . As a result, the flexible N,P-CNFs/GN/BC paper electrode shows appreciable areal capacitance (1990 mF cm-2 in KOH and 2588 mF cm-2 in H2 SO4 electrolytes) without sacrificing gravimetric capacitance (248.8 F g-1 and 323.5 F g-1 ), exhibits excellent cycling ability (without capacity loss after 20 000 cycles), and remarkable tensile strength (42.8 MPa). By direct coupling of two membrane electrodes, the symmetric supercapacitor delivers a prominent areal capacitance of 690 mF cm-2 in KOH and 898 mF cm-2 in H2 SO4 , and remarkable power/energy density (19.98 mW cm-2 /0.096 mW h cm-2 in KOH and 35.01 mW cm-2 /0.244 mW h cm-2 in H2 SO4 ). Additionally, it shows stable behavior in both bent and flat states. These results promote new opportunities for N,P-CNFs/GN/BC paper electrodes as high areal performance, freestanding electrodes for flexible supercapacitors.

13.
Pestic Biochem Physiol ; 126: 42-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26778433

RESUMEN

American sloughgrass is a troublesome annual grass weed in winter wheat field rotated with rice in China. The overreliance on acetyl-coenzyme A carboxylase (ACCase) inhibiting herbicides has resulted in resistance evolution in this weed. In this study, the cross-resistance patterns to fenoxaprop-p-ethyl, clodinafop-propargyl, fluazifop-p-butyl, haloxyfop-p-methyl, sethoxydim, clethodim and pinoxaden were established using purified plants individually homozygous for specific mutant ACCase alleles. Results indicated that 1781Leu allele endows high-level resistance to APPs, CHDs and pinoxaden while confers moderate resistance to haloxyfop-p-methyl. The 2027Cys and 2041Asn alleles endow high-level resistance to APPs and pinoxaden and lower level resistance to CHDs. The 2078Gly allele confers high-level resistance to all herbicides tested in this study, however, moderate resistance to sethoxydim. The 2096Ala very likely endows high-level resistance to fluazifop-p-butyl, haloxyfop-p-methyl and moderate resistance to sethoxydim. In addition, one undefined resistance mechanism was involved in population SD-04.


Asunto(s)
Acetil-CoA Carboxilasa/genética , Herbicidas/toxicidad , Proteínas de Plantas/genética , Poaceae/efectos de los fármacos , Acetil-CoA Carboxilasa/antagonistas & inhibidores , Ciclohexanonas/toxicidad , Relación Dosis-Respuesta a Droga , Resistencia a los Herbicidas/genética , Compuestos Heterocíclicos con 2 Anillos/toxicidad , Oxazoles/toxicidad , Proteínas de Plantas/antagonistas & inhibidores , Poaceae/enzimología , Poaceae/genética , Propionatos/toxicidad , Piridinas/toxicidad
14.
Pestic Biochem Physiol ; 126: 22-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26778430

RESUMEN

Fenoxaprop-P-ethyl-resistant Alopecurus japonicus has become a recurring problem in winter wheat fields in eastern China. Growers have resorted to using mesosulfuron-methyl, an acetolactate synthase (ALS)-inhibiting herbicide, to control this weed. A single A. japonicus population (AH-15) resistant to fenoxaprop-P-ethyl and mesosulfuron-methyl was found in Anhui Province, China. The results of whole-plant dose-response experiments showed that AH-15 has evolved high-level resistance to fenoxaprop-P-ethyl (95.96-fold) and mesosulfuron-methyl (39.87-fold). It was shown via molecular analysis that resistance to both fenoxaprop-P-ethyl and mesosulfuron-methyl was due to an amino acid substitution of Ile1781 to Leu in acetyl-CoA carboxylase (ACCase) and a substitution of Trp 574 to Leu in ALS, respectively. Whole-plant bioassays indicated that the AH-15 population was resistant to the ACCase herbicides clodinafop-propargyl, clethodim, sethoxydim and pinoxaden as well as the ALS herbicides pyroxsulam, flucarbazone-Na and imazethapyr, but susceptible to the ACCase herbicide haloxyfop-R-methyl. This work reports for the first time that A. japonicus has developed resistance to ACCase- and ALS-inhibiting herbicides due to target site mutations in the ACCase and ALS genes.


Asunto(s)
Acetolactato Sintasa/genética , Acetil-CoA Carboxilasa/genética , Herbicidas/toxicidad , Proteínas de Plantas/genética , Poaceae/genética , Acetolactato Sintasa/antagonistas & inhibidores , Acetil-CoA Carboxilasa/antagonistas & inhibidores , Sustitución de Aminoácidos , Secuencia de Bases , China , ADN de Plantas/genética , Resistencia a los Herbicidas/genética , Datos de Secuencia Molecular , Mutación , Proteínas de Plantas/antagonistas & inhibidores , Poaceae/efectos de los fármacos , Análisis de Secuencia de ADN
15.
Pestic Biochem Physiol ; 119: 9-15, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25868811

RESUMEN

Pseudosclerochloa kengiana is a troublesome annual grass weed of wheat fields in the rice-wheat double cropping areas in China. Resistance has evolved in P. kengiana under continuously selective pressure of ACCase-inhibiting herbicides. Whole-plant experiments showed that two suspected resistant populations 12-SD-12 and 12-SD-13 were highly resistant to fenoxaprop-P-ethyl (69.9- and 57.2-fold); moderately resistant to clodinafop-propargyl (5.9- and 4.1-fold) and pinoxaden (4.4- and 3.5-fold); lowly resistant to fluazifop-P-butyl (2.2- and 2.0-fold) and sethoxydim (1.8- and 1.6-fold), but were sensitive to clethodim (1.0- and 0.9-fold) and mesosulfuron-methyl (1.1- and 0.9-fold). Molecular analyses confirmed that a Trp1999 to Ser mutation was present in the resistant populations. Two dCAPS markers were also developed to positively determine the wild type Trp and mutant Ser alleles at ACCase position 1999. All 350 individual plants of 12-SD-12 population analysed were heterozygous mutants. Meanwhile, 318 mutant heterozygotes and 32 wild types were detected from the 12-SD-13 population. In addition, the analysis of plant genotype and phenotype showed that all wild type plants were killed after treatment with any one of the ACCase-inhibiting herbicides used, while individual plants carrying the W1999S mutation survived except when treated with clethodim. To our knowledge, this is the first report of pinoxaden resistance and a Trp-1999-Ser mutation in the plastid ACCase for P. kengiana.


Asunto(s)
Acetil-CoA Carboxilasa/genética , Resistencia a los Herbicidas , Herbicidas/farmacología , Proteínas de Plantas/genética , Poaceae/efectos de los fármacos , Poaceae/enzimología , Acetil-CoA Carboxilasa/metabolismo , Alelos , Mutación , Oxazoles/farmacología , Proteínas de Plantas/metabolismo , Poaceae/genética , Propionatos/farmacología
16.
Pestic Biochem Physiol ; 124: 66-72, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26453232

RESUMEN

Shortawn foxtail (Alopecurus aequalis) is a troublesome grass weed infesting winter wheat and oilseed rape productions in China. Fenoxaprop-p-ethyl and mesosulfuron-methyl failed to control shortawn foxtail of AHSX-1 population collected from a wheat field in Shou County, Anhui province. Molecular analyses revealed that Asp2078Gly mutation of ACCase and Trp574Leu mutation of AHAS were present in plants of the AHSX-1 population. The homozygous plants were isolated and cultured until seed maturity. Whole-plant herbicide bioassays were conducted in the greenhouse using the purified seeds of F1 generation. Dose-response experiments showed that the AHSX-1 population has evolved a very high level resistance to fenoxaprop-p-ethyl (RI = 275) and mesosulfuron-methyl (RI = 788). To determine the sensitivity to other herbicides, assays were conducted at the single recommended rate of each herbicide. Based on the results, the AHSX-1 population was considered to be highly resistant to clodinafop-propargyl, pyroxsulam and flucarbazone-sodium, moderately or highly resistant to quizalofop-p-ethyl, clethodim, sethoxydim and pinoxaden, and susceptible to isoproturon and chlorotoluron. This is the first report of Asp2078Gly mutation in shortawn foxtail and the two robust dCAPS markers designed could quickly detect Asp2078 and Trp574 mutations in ACCase and AHAS gene of shortawn foxtail, respectively.


Asunto(s)
Acetolactato Sintasa/genética , Acetil-CoA Carboxilasa/genética , Herbicidas/toxicidad , China , Ciclohexanonas/toxicidad , Resistencia a los Herbicidas/genética , Compuestos Heterocíclicos con 2 Anillos/toxicidad , Mutación , Oxazoles/toxicidad , Propionatos/toxicidad , Piridinas/toxicidad , Quinoxalinas/toxicidad , Compuestos de Sulfonilurea/toxicidad
17.
Pestic Biochem Physiol ; 117: 31-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25619909

RESUMEN

Water chickweed (Myosoton aquaticum L.), a competitive broadleaf weed, is widespread in wheat fields in China. Tribenuron and pyroxsulam failed to control water chickweed in the same field in Qiaotian Village in 2011 and 2012, respectively. An initial tribenuron resistance confirmation test identified a resistant population (AH02). ALS gene sequencing revealed a previously unreported substitution of Glu for Pro at amino acid position 197 in resistant individuals. A purified subpopulation (WRR04) that was individually homozygous for the Pro197Glu substitution was generated and characterized in terms of its response to different classes of ALS inhibitors. A whole-plant experiment showed that the WRR04 population exhibited broad-spectrum resistance to tribenuron (SU, 318-fold), pyrithiobac sodium (PTB, > 197-fold), pyroxsulam (TP, 81-fold), florasulam (TP, > 36-fold) and imazethapyr (IMI, 11-fold). An in vitro ALS assay confirmed that the ALS from WRR04 showed high resistance to all the tested ALS inhibitors. These results established that the Pro197Glu substitution endows broad-spectrum resistance across ALS inhibitors in water chickweed. In addition, molecular markers were developed to rapidly identify the Pro197Glu mutation.


Asunto(s)
Acetolactato Sintasa/genética , Caryophyllaceae/genética , Resistencia a los Herbicidas/genética , Malezas/genética , Acetolactato Sintasa/antagonistas & inhibidores , Sustitución de Aminoácidos , Arilsulfonatos/farmacología , Secuencia de Bases , Benzoatos/farmacología , Caryophyllaceae/efectos de los fármacos , Caryophyllaceae/enzimología , ADN de Plantas/genética , Herbicidas/farmacología , Ácidos Nicotínicos/farmacología , Malezas/efectos de los fármacos , Malezas/enzimología , Polimorfismo de Nucleótido Simple , Pirimidinas/farmacología , Análisis de Secuencia de ADN , Sulfonamidas/farmacología
18.
Pestic Biochem Physiol ; 110: 57-62, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24759052

RESUMEN

American sloughgrass (Beckmannia syzigachne) is a troublesome weed in winter wheat field rotated with rice in China. Fenoxaprop-p-ethyl and pinoxaden were observed failing to control American sloughgrass in the same filed in Lujiang county in 2011 and 2012, respectively. Whole-plant bioassay was conducted to determine the resistance to fenoxaprop-p-ethyl, pinoxaden and other herbicides in American sloughgrass. Dose-response experiment indicated that Lujiang population was highly resistant to fenoxaprop-p-ethyl (199.8-fold), pinoxaden (76.2-fold), clodinafop-propargyl (334.1-fold) and sethoxydim (15.9-fold); moderately resistant to clethodim (6.3-fold), susceptible to mesosulfuron-methyl, flucarbazone-sodium, pyroxsulam and isoproturon. Partial gene of CT domain was cloned and sequenced to confirm the molecular mechanism of resistance to ACCase-inhibiting herbicides. A Trp2027Cys mutation was found in Lujiang population according to the sequencing result. This mutation is the molecular mechanism of resistance to fenoxaprop-p-ethyl in Lujiang population. Furthermore the Trp2027Cys mutation very likely results in cross resistance to clodinafop-propargyl and pinoxaden in Lujiang population. 103 mutant homozygotes were detected from the 108 plants tested using a rapid dCAPS method developed in this paper. This is the first report of pinoxaden resistance and a mutation at position of 2027 for American sloughgrass.


Asunto(s)
Acetil-CoA Carboxilasa/antagonistas & inhibidores , Herbicidas/toxicidad , Lolium/efectos de los fármacos , Acetil-CoA Carboxilasa/genética , Secuencia de Aminoácidos , China , Ciclohexanonas/toxicidad , Resistencia a los Herbicidas , Compuestos Heterocíclicos con 2 Anillos/toxicidad , Lolium/genética , Datos de Secuencia Molecular , Mutación , Oxazoles/toxicidad , Propionatos/toxicidad , Piridinas/toxicidad
19.
RSC Adv ; 14(5): 2889-2895, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38239456

RESUMEN

For developing commercially viable LiNi1-x-yMnxCoyO2 (NCM), it is necessary to alleviate the irreversible chemical process upon Li-ion insertion/extraction, which primarily accounts for prevailing capacity loss, impedance buildup as well as low columbic efficiency. To resolve this issue, we herein propose a simple but novel method to alter the chemical composition by a facile treatment of H2O2, which remarkably reduces the cation mixing of Li+/Ni2+ and residual lithium on the cathode. The tailored composition contributes great resistance to the structural reconstruction and enhancement in structural reversibility, as shown by in situ Raman and high-resolution transmission electron microscope (HRTEM) results. Thus, the modified sample outperforms the pristine one; it exhibits cyclability with 95.7% capacity retention over 300 cycles, high columbic efficiency and enhanced rate capability.

20.
RSC Adv ; 14(17): 12247-12254, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38628474

RESUMEN

Ni-rich layered materials LiNi0.8Co0.1Mn0.1O2 attracts extensive interest to build high-performance lithium-ion batteries, but ground challenges, e.g., unfavorable phase transfer and interfacial parasitic reactions during cycling, especially after being exposure to the air for a long time, greatly limit their practical utilization. Here, we prove that those issues of Ni-rich layered materials can be alleviated by concurrently incorporating the Al3+ and PO34-, and conduct corresponding comprehensive studies to explore mechanisms of the enhanced electrochemical performances. It is suggested that the phase transition (H2 to H3) that related to the lattice contraction can be suppressed after Al3+ and PO34- co-doping, leading to improved cycling stability. Additionally, the co-doping successfully mitigates the chemical reaction between the Ni-based oxides and the ambient air, significantly improving the reversibility of lithium intercalation and charge transfer kinetics against long-time storage. Specifically, the Al3+ and PO34- co-doped material maintains 94.1% capacity retention of 150 cycles before storage, and 73.6% capacity retention of 100 cycles after being stored in ambient air for 30 days, which is much better than that of the undoped one.

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