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1.
Mol Psychiatry ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003414

RESUMO

Neuroligin-3 (Nlgn3) is an autism-associated cell-adhesion molecule that interacts with neurexins and is robustly expressed in both neurons and astrocytes. Neuronal Nlgn3 is an essential regulator of synaptic transmission but the function of astrocytic Nlgn3 is largely unknown. Given the high penetrance of Nlgn3 mutations in autism and the emerging role of astrocytes in neuropsychiatric disorders, we here asked whether astrocytic Nlgn3 might shape neural circuit properties in the cerebellum similar to neuronal Nlgn3. Imaging of tagged Nlgn3 protein produced by CRISPR/Cas9-mediated genome editing showed that Nlgn3 is enriched in the cell body but not the fine processes of cerebellar astrocytes (Bergmann glia). Astrocyte-specific knockout of Nlgn3 did not detectably alter the number of synapses, synaptic transmission, or astrocyte morphology in mouse cerebellum. However, spatial transcriptomic analyses revealed a significant shift in gene expression among multiple cerebellar cell types after the deletion of astrocytic Nlgn3. Hence, in contrast to neuronal Nlgn3, astrocytic Nlgn3 in the cerebellum is not involved in shaping synapses but may modulate gene expression in specific brain areas.

2.
PLoS Biol ; 19(4): e3001190, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33844686

RESUMO

Chemical insecticides have been heavily employed as the most effective measure for control of agricultural and medical pests, but evolution of resistance by pests threatens the sustainability of this approach. Resistance-conferring mutations sometimes impose fitness costs, which may drive subsequent evolution of compensatory modifier mutations alleviating the costs of resistance. However, how modifier mutations evolve and function to overcome the fitness cost of resistance still remains unknown. Here we show that overexpression of P450s not only confers imidacloprid resistance in the brown planthopper, Nilaparvata lugens, the most voracious pest of rice, but also leads to elevated production of reactive oxygen species (ROS) through metabolism of imidacloprid and host plant compounds. The inevitable production of ROS incurs a fitness cost to the pest, which drives the increase or fixation of the compensatory modifier allele T65549 within the promoter region of N. lugens peroxiredoxin (NlPrx) in the pest populations. T65549 allele in turn upregulates the expression of NlPrx and thus increases resistant individuals' ability to clear the cost-incurring ROS of any source. The frequent involvement of P450s in insecticide resistance and their capacity to produce ROS while metabolizing their substrates suggest that peroxiredoxin or other ROS-scavenging genes may be among the common modifier genes for alleviating the fitness cost of insecticide resistance.


Assuntos
Hemípteros/efeitos dos fármacos , Resistência a Inseticidas/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Oryza/parasitologia , Peroxirredoxinas/fisiologia , Adaptação Biológica/efeitos dos fármacos , Adaptação Biológica/genética , Alelos , Animais , Mapeamento Cromossômico , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Genes de Insetos/efeitos dos fármacos , Genes Modificadores/efeitos dos fármacos , Genes Modificadores/fisiologia , Estudos de Associação Genética , Aptidão Genética/efeitos dos fármacos , Hemípteros/fisiologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Oryza/efeitos dos fármacos , Peroxirredoxinas/genética , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade
3.
Environ Res ; 262(Pt 2): 119932, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39241855

RESUMO

China's groundwater is facing a significant threat from nitrate pollution. Here we analyzed 2348 regional surveys of groundwater nitrate levels in China from 1990 to 2020, examining distribution, trends, and drivers. This study uncovers a concerning rise in nitrate pollution, with estimated median nitrate levels climbing from 3.84 mg/L in 1990 to 6.94 mg/L in 2020. A stark contrast is observed between regions: the northern areas have a median nitrate concentration of 8.54 mg/L, significantly higher than the southern regions, where the median is just 7.15 mg/L. From 1990 to 2020, agricultural activity consistently emerges as the dominant driver of changes in groundwater nitrate concentrations, while groundwater exploitation, domestic pollution, and industrial production also contribute to varying degrees. This analysis highlights the urgency for region-specific policies and interventions to address the escalating nitrate pollution in China's groundwater.

4.
Sensors (Basel) ; 24(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38544120

RESUMO

Community wastewater management systems (CWMS) are small-scale wastewater treatment systems typically in regional and rural areas with less sophisticated treatment processes and often managed by local governments or communities. Research and industrial applications have demonstrated that online UV-Vis sensors have great potential for improving wastewater monitoring and treatment processes. Existing studies on the development of surrogate parameters with models from spectral data for wastewater were largely limited to lab-based. In contrast, industrial applications of these sensors have primarily targeted large wastewater treatment plants (WWTPs), leaving a gap in research for small-scale WWTPs. This paper demonstrates the suitability of using a field-based online UV-Vis sensor combined with advanced data analytics for CWMSs as an early warning for process upset to support sustainable operations. An industry case study is provided to demonstrate the development of surrogate monitoring parameters for total suspended solids (TSSs) and chemical oxygen demand (COD) using the UV-Vis spectral data from an online UV-Vis sensor. Absorbances at a wavelength of 625 nm (UV625) and absorbances at a wavelength of 265 nm (UV265) were identified as surrogate parameters to measure TSSs and COD, respectively. This study contributes to the improvement of WWTP performance with a continuous monitoring system by developing a process monitoring framework and optimization strategy.

5.
J Org Chem ; 88(1): 513-524, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36545950

RESUMO

Herein, the efficient photoredox/nickel dual-catalyzed cyanoalkylation reaction of enamides is illustrated. A wide scope of enamides and cycloketone oxime esters was well-tolerated, affording the synthetically versatile and geometrically defined ß-cyanoalkylated enamide scaffolds. The synthetic practicality of this protocol was revealed by gram-scale reactions, further transformations of enamides, and late-stage modifications of biologically active molecules.


Assuntos
Amidas , Níquel , Estrutura Molecular , Catálise
6.
Clin Oral Investig ; 27(8): 4531-4539, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37285103

RESUMO

OBJECTIVES: The prediction of posttreatment outcomes is conducive to the final determination of ideal therapeutic options. However, the prediction accuracy in orthodontic class III cases is unclear. Therefore, this study conducted exploration on prediction accuracy in orthodontic class III patients using the Dolphin® software. MATERIALS AND METHODS: In this retrospective study, lateral cephalometric radiographs of pre- and posttreatment were collected from 28 angle class III adults who received completed non-orthognathic orthodontic therapy (8 males, 20 females; mean age = 20.89 ± 4.26 years). The values of 7 posttreatment parameters were recorded and inserted into the Dolphin® Imaging software to generate a predicted outcome, and then the prediction radiograph and actual posttreatment radiograph were superimposed and compared in terms of soft tissue parameters and landmarks. RESULTS: The prediction showed significant differences with the actual outcomes in nasal prominence (the difference between the prediction and the actual value was - 0.78 ± 1.82 mm), the distance from the lower lip to the H line (0.55 ± 1.11 mm), and the distance from the lower lip to the E line (0.77 ± 1.62 mm) (p < 0.05). Point subnasale (Sn) (an accuracy of 92.86% in the horizontal direction and 100% in the vertical direction in 2 mm) and point soft tissue A (ST A) (an accuracy of 92.86% in the horizontal direction and 85.71% in the vertical direction in 2 mm) were proven to be the most accurate landmarks, while the predictions in the chin region were relatively inaccurate. Furthermore, the predictions in the vertical direction were of higher accuracy compared to the horizontal direction except for the points around the chin. CONCLUSIONS: The Dolphin® software demonstrated acceptable prediction accuracy in midfacial changes in class III patients. However, there were still limitations for changes in the chin and lower lip prominence. CLINICAL RELEVANCE: Clarifying the accuracy of Dolphin® software in predicting soft tissue changes of orthodontic class III cases will facilitate physician-patient communication and clinical treatment.


Assuntos
Golfinhos , Má Oclusão Classe III de Angle , Masculino , Feminino , Animais , Face/anatomia & histologia , Estudos Retrospectivos , Queixo/anatomia & histologia , Software , Lábio/diagnóstico por imagem , Cefalometria/métodos , Mandíbula
7.
Appl Environ Microbiol ; 88(6): e0231721, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35108080

RESUMO

Volatile organic compounds (VOCs) produced by microorganisms are considered promising environmental-safety fumigants for controlling postharvest diseases. Ceratocystis fimbriata, the pathogen of black spot disease, seriously affects the quality and yield of sweet potato in the field and postharvest. This study tested the effects of VOCs produced by Streptomyces setonii WY228 on the control of C. fimbriata in vitro and in vivo. The VOCs exhibited strong antifungal activity and significantly inhibited the growth of C. fimbriata. During the 20-day storage, VOC fumigation significantly controlled the occurrence of the pathogen, increased the content of antioxidants and defense-related enzymes and flavonoids, and boosted the starch content so as to maintain the quality of the sweet potatoes. Headspace analysis showed that the volatiles 2-ethyl-5-methylpyrazine and dimethyl disulfide significantly inhibited the mycelial growth and spore germination of C. fimbriata in a dose-dependent manner. Fumigation with 100 µL/L 2-ethyl-5-methylpyrazine completely controlled the pathogen in vivo after 10 days of storage. Transcriptome analysis showed that volatiles mainly downregulated the ribosomal synthesis genes and activated the proteasome system of the pathogen in response to VOC stress, while the genes related to spore development, cell membrane synthesis, mitochondrial function, and hydrolase and toxin synthesis were also downregulated, indicating that WY228-produced VOCs have diverse modes of action for pathogen control. Our study demonstrates that fumigation of sweet potato tuberous roots with S. setonii WY228 or use of formulations based on the VOCs is a promising new strategy to control sweet potato and other food and fruit pathogens during storage and shipment. IMPORTANCE Black spot disease caused by Ceratocystis fimbriata has caused huge economic losses to worldwide sweet potato production. At present, the control of C. fimbriata mainly depends on toxic fungicides, and there is a lack of effective alternative strategies. The research on biological control of sweet potato black spot disease is also very limited. An efficient biocontrol technique against pathogens using microbial volatile organic compounds could be an alternative method to control this disease. Our study revealed the significant biological control effect of volatile organic compounds of Streptomyces setonii WY228 on black spot disease of postharvest sweet potato and the complex antifungal mechanism against C. fimbriata. Our data demonstrated that Streptomyces setonii WY228 and its volatile 2-ethyl-5-methylpyrazine could be a candidate strain and compound for the creation of fumigants and showed the important potential of biotechnology applications in the field of food and agriculture.


Assuntos
Ascomicetos , Ipomoea batatas , Streptomyces , Compostos Orgânicos Voláteis , Antifúngicos/farmacologia , Ipomoea batatas/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Compostos Orgânicos Voláteis/farmacologia
8.
Mol Ecol ; 31(15): 3999-4016, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35665559

RESUMO

Switching to a new host plant is a driving force for divergence and speciation in herbivorous insects. This process of incorporating a novel host plant into the diet may require a number of adaptations in the insect herbivores that allow them to consume host plant tissue that may contain toxic secondary chemicals. As a result, herbivorous insects are predicted to have evolved efficient ways to detoxify major plant defences and increase fitness by either relying on their own genomes or by recruiting other organisms such as microbial gut symbionts. In the present study we used parallel metatranscriptomic analyses of Altica flea beetles and their gut symbionts to explore the contributions of beetle detoxification mechanisms versus detoxification by their gut consortium. We compared the gut meta-transcriptomes of two sympatric Altica species that feed exclusively on different host plant species as well as their F1 hybrids that were fed one of the two host plant species. These comparisons revealed that gene expression patterns of Altica are dependent on both beetle species identity and diet. The community structure of gut symbionts was also dependent on the identity of the beetle species, and the gene expression patterns of the gut symbionts were significantly correlated with beetle species and plant diet. Some of the enriched genes identified in the beetles and gut symbionts are involved in the degradation of secondary metabolites produced by plants, suggesting that Altica flea beetles may use their gut microbiota to help them feed on and adapt to their host plants.


Assuntos
Besouros , Animais , Besouros/genética , Herbivoria , Insetos , Plantas , Simbiose/genética
9.
Arch Insect Biochem Physiol ; 111(4): e21966, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36106458

RESUMO

The family Disteniidae is a moderately large and widely distributed lineage. Distenia punctulatoides belongs to the family Disteniidae from the cerambycoid assemblage. Here, we report the complete mitogenome of D. punctulatoides, which is 15,675 bp in length. It contains 37 genes and a noncoding control region, which are arranged in the same order as that of the putative ancestor of beetles. The total base composition of the new mitogenome is 40.2% for A, 17.1% for C, 10.0% for G, and 32.7% for T. The new mitogenomic organization, nucleotide composition, and codon usage do not differ significantly from other beetles. Using available complete mitogenomes, the high-level phylogeny of the family Disteniidae was explored. The phylogenetic analyses showed that Disteniidae were monophyletic, and the genus Distenia grouped with the genus Clytomelegena as sister groups. Combining the morphological and molecular data, Typodryas Thomson, 1864 is suggested to be a junior synonym of Distenia Lepeletier and Audinet-Serville, 1828.


Assuntos
Besouros , Genoma Mitocondrial , Animais , Filogenia , Besouros/genética , Composição de Bases
10.
Antonie Van Leeuwenhoek ; 115(12): 1405-1420, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36284037

RESUMO

Arctium lappa L. is one of the medicinal and food homologous plants in China, which is rich in nutrients and medicinal ingredients. The use of plant growth-promoting (PGP) endophytic bacteria is an alternative to reducing chemical fertilizers in agricultural production. The aim of this study was to analyze the diversity of endophytic bacteria in different cultivars of A. lappa L. collected from two geographical locations in China and evaluate PGP traits of the isolates and their potential PGP ability in greenhouse condition. Endophytic bacterial community was investigated by culture-dependent and culture-independent methods. Isolates were screened and investigated for multiple PGP traits, and representative strains were inoculated host seedlings to evaluate the growth promoting effect. A total of 348 endophytic bacteria were obtained and they were distributed into 4 phyla and 30 genera. In addition, high throughput sequencing revealed more abundant bacterial community, including 17 bacterial phyla and 207 genera. A high proportion of PGP traits were detected, including production of indole acetic acid, siderophore, ammonia and phosphate solubilization. Four representative strains with multiple PGP traits of the most dominant genera (Bacillus, Pantoea, Microbacterium and Pseudomonas) were further selected for host inoculation and growth promoting evaluation, and they significantly increase seedlings length, root length and fresh weight. This study demonstrated that A. lappa L. harbors abundant endophytic bacteria, and some endophytic bacteria showed good potential for the development of microbial fertilizer in the future.


Assuntos
Arctium , Pantoea , Plantas Medicinais , Endófitos , Desenvolvimento Vegetal , Plântula , Raízes de Plantas/microbiologia
11.
J Environ Manage ; 317: 115331, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35636104

RESUMO

Photovoltaic (PV) technologies are critical for sustainable energy supply, climate change mitigation, and energy security with lower environmental impact compared to other generation alternatives. Despite the environmental benefits of PV technologies, one of these major downsides is the growing concern over the environmental impact due to risks associated with improper waste handling and disposal of decommissioned PV panels. As a result, there are strong incentives for PV panel recycling to recover valuable resources and mitigate risks caused by hazardous substances. This study proposes a reverse logistical planning framework for collecting end-of-life PV panels, which aims to support the integration of existing recycling technologies and collection schemes using a holistic approach for ensuring feasibility and reducing environmental impact. The framework reviews current recycling methodologies for PV waste and the state of PV markets, including PV uptake, waste stream forecast, collection and logistic strategies. Additionally, South Australia is used as the context of analysis for a case study where the framework is applied to identify the potential strategies for handling and collection of end-of-life PV panels based on current PV uptake and waste stream forecast. As a result, capital, transportation and operation costs can be reduced, contributing to lower overall recycling cost for the PV waste treatment and a more efficient reverse logistic system.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Meio Ambiente , Reciclagem/métodos , Eliminação de Resíduos/métodos , Austrália do Sul , Gerenciamento de Resíduos/métodos
12.
BMC Oral Health ; 22(1): 495, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384518

RESUMO

BACKGROUND: An ideal relationship of anterior teeth is closely related to postoperative function, stability, and aesthetics. Therefore, it is necessary to estimate the proportion of anterior teeth when communicating with patients about possible treatment plans and outcomes. This study aimed to establish a simple method for assessing the proportion of anterior teeth and to identify the standard ratio value to provide references for clinical work. METHODS: Five hundred fourteen patients were divided into derivation, standard, and validation datasets. We first deduced our novel simplified anterior tooth ratio (SATR) by finding the key teeth with the derivation datasets, then established standard values by measuring the standard models, and finally validated the diagnostic performance of SATR. Independent sample t-test was used to select key teeth. Pearson's correlation analysis and linear regression analysis was used to test and verify the correlation between SATR and the anterior Bolton ratio. Chi-square test and diagnostic test were used to verify the diagnostic results using SATR. P values of < 0.05 were considered statistically significant. RESULTS: Patients with an abnormal anterior Bolton ratio were more likely to have variations in the maxillary and mandibular lateral incisors. Therefore, the ratio of maxillary and mandibular lateral incisors was chosen as a simple way to assess the anterior tooth ratio and was defined as SATR (simplified anterior tooth ratio). A positive correlation was observed between SATR and anterior Bolton ratio (r = 0.702, p < 0.001), with the linear regression equation as follows: y = 0.503 + 0.328x, x = SATR, y = anterior Bolton ratio. The standard value of SATR was established (85.69% ± 3.57%) and proven reliable in clinical practice. CONCLUSIONS: The ratio of maxillary and mandibular lateral incisors can be used to estimate the anterior tooth ratio, which showed high reliability and efficiency.


Assuntos
Incisivo , Maxila , Humanos , Odontometria , Reprodutibilidade dos Testes , Incisivo/anatomia & histologia , Etnicidade
13.
Mol Plant Microbe Interact ; 34(7): 839-841, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33616420

RESUMO

Pseudomonas chlororaphis subsp. aureofaciens SPS-41 is a plant growth-promoting rhizobacterium with biocontrol potential that was isolated from the rhizosphere of sweet potato in Xuzhou, Jiangsu Province, China. Our previous study demonstrated that volatile organic compounds (VOCs) produced by SPS-41 inhibited black spot disease fungi Ceratocystis fimbriata in postharvest sweet potatoes and a variety of other plant pathogens, and the VOCs also displayed strong nematocidal activity. In order to further explore the application potential of this strain, we here report the complete genome sequence of strain SPS-41. The genome consists of one chromosome (6,757,898 bp) with a G+C content 63.10%, which contains 5,951 coding genes, 67 transfer RNA genes, 16 ribosome RNA genes, and 85 other non-coding RNA genes. No plasmid was detected. The information of the genome will provide resources for studying the biocontrol mechanism of this strain.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Pseudomonas , Rizosfera , Fungos , Desenvolvimento Vegetal , Pseudomonas/genética
14.
BMC Genomics ; 22(1): 243, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827435

RESUMO

BACKGROUND: Altica (Coleoptera: Chrysomelidae) is a highly diverse and taxonomically challenging flea beetle genus that has been used to address questions related to host plant specialization, reproductive isolation, and ecological speciation. To further evolutionary studies in this interesting group, here we present a draft genome of a representative specialist, Altica viridicyanea, the first Alticinae genome reported thus far. RESULTS: The genome is 864.8 Mb and consists of 4490 scaffolds with a N50 size of 557 kb, which covered 98.6% complete and 0.4% partial insect Benchmarking Universal Single-Copy Orthologs. Repetitive sequences accounted for 62.9% of the assembly, and a total of 17,730 protein-coding gene models and 2462 non-coding RNA models were predicted. To provide insight into host plant specialization of this monophagous species, we examined the key gene families involved in chemosensation, detoxification of plant secondary chemistry, and plant cell wall-degradation. CONCLUSIONS: The genome assembled in this work provides an important resource for further studies on host plant adaptation and functionally affiliated genes. Moreover, this work also opens the way for comparative genomics studies among closely related Altica species, which may provide insight into the molecular evolutionary processes that occur during ecological speciation.


Assuntos
Besouros , Sifonápteros , Animais , Besouros/genética , Evolução Molecular , Genoma , Genômica
15.
J Gen Virol ; 102(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33236978

RESUMO

Two Autographa californica nucleopolyhedrovirus (AcMNPV) encoded miRNAs, AcMNPV-miR-1 and AcMNPV-miR-3, have been reported by us in 2013 and 2019, respectively. Here, we present an integrated investigation of AcMNPV-encoded miRNAs, which include the above two miRNAs and three additional newly identified miRNAs. Six candidate miRNAs were predicted through small RNA deep sequencing and bioinformatics, of which, five were validated. Three miRNAs are located opposite the coding sequences, the other two are located in the coding sequences of viral genes. Targets in both virus and host were predicted and subsequently tested using dual-luciferase reporter assays. The validated targets were found mainly in AcMNPV, except for the targets of AcMNPV-miR-4, which are all host genes. Based on reporter assays, the five miRNAs predominantly function by down-regulating their targets. The transcription start sites of these miRNAs were bioinformatic screened based on known baculovirus promoter motifs. Our study reveals that AcMNPV-encoded miRNAs function as fine modulators of the interactions between host and virus by regulating viral and/or host genes.


Assuntos
MicroRNAs/genética , Nucleopoliedrovírus/genética , Spodoptera/virologia , Proteínas Virais/metabolismo , Animais , Sequência de Bases , Genes Virais , Nucleopoliedrovírus/isolamento & purificação , Células Sf9 , Spodoptera/genética , Proteínas Virais/genética , Replicação Viral/genética
16.
J Synchrotron Radiat ; 28(Pt 3): 910-918, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949998

RESUMO

The Long Short-Term Memory neural network (LSTM) has excellent learning ability for the time series of the nuclear pulse signal. It can accurately estimate the parameters (such as amplitude, time constant, etc.) of the digitally shaped nuclear pulse signal (especially the overlapping pulse signal). However, due to the large number of pulse sequences, the direct use of these sequences as samples to train the LSTM increases the complexity of the network, resulting in a lower training efficiency of the model. The convolution neural network (CNN) can effectively extract the sequence samples by using its unique convolution kernel structure, thus greatly reducing the number of sequence samples. Therefore, the CNN-LSTM deep neural network is used to estimate the parameters of overlapping pulse signals after digital trapezoidal shaping of exponential signals. Firstly, the estimation of the trapezoidal overlapping nuclear pulse is considered to be obtained after the superposition of multiple exponential nuclear pulses followed by trapezoidal shaping. Then, a data set containing multiple samples is set up; each sample is composed of the sequence of sampling values of the trapezoidal overlapping nuclear pulse and the set of shaping parameters of the exponential pulse before digital shaping. Secondly, the CNN is used to extract the abstract features of the training set in these samples, and then these abstract features are applied to the training of the LSTM model. In the training process, the pulse parameter set estimated by the present neural network is calculated by forward propagation. Thirdly, the loss function is used to calculate the loss value between the estimated pulse parameter set and the actual pulse parameter set. Finally, a gradient-based optimization algorithm is applied to update the weight by getting back the loss value together with the gradient of the loss function to the network, so as to realize the purpose of training the network. After model training was completed, the sampled values of the trapezoidal overlapping nuclear pulse were used as input to the CNN-LSTM model to obtain the required parameter set from the output of the CNN-LSTM model. The experimental results show that this method can effectively overcome the shortcomings of local convergence of traditional methods and greatly save the time of model training. At the same time, it can accurately estimate multiple trapezoidal overlapping pulses due to the wide width of the flat top, thus realizing the optimal estimation of nuclear pulse parameters in a global sense, which is a good pulse parameter estimation method.

17.
Phys Chem Chem Phys ; 23(32): 17113-17128, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34346439

RESUMO

Inorganic lead halide perovskite (ILHP) nanocrystals (NCs) show great potential in solid state lighting and next generation display technology due to their excellent optical properties. However, almost all ILHP NCs are still facing the problem of unstable luminescence properties caused by heating and/or UV illumination. Further improving the thermal and photo stability of ILHP NCs has become the most urgent challenge for their practical application. This Perspective review specifically focuses on the thermal and photo stability of ILHP NCs, discusses and analyzes the factors that affect the thermal and photo stability of ILHP NCs from the perspective of surface ligands and structure composition, summarizes the current strategies to improve the thermal and photo stability of ILHP NCs, and presents the key challenges and perspectives on the research for the improvement of thermal and photo stability of ILHP NCs.

18.
PLoS Genet ; 14(10): e1007725, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30332402

RESUMO

Symbiotic bacteria are important drivers of phenotypic diversity in insects. One of the widespread symbionts to have emerged belongs to the genus Arsenophonus, however, its biological functions in most host insects remain entirely unknown. Here we report two distinct Arsenophonus strains in the brown planthopper (BPH), Nilaparvata lugens, a major pest insect in Asian countries that causes significant economic damage through rice crop destruction. Genomic resequencing data suggested that one Arsenophonus strain (S-type) negatively affected the insecticide resistance of the host. Indeed, replacement of the resident Arsenophonus with the S-type Arsenophonus significantly decreased host insecticide resistance. Transcriptome and metabolome analysis revealed down-regulation of xenobiotic metabolism and increased amino acid accumulation in the S-type Arsenophonus infected host. This study demonstrates how a symbiont-mediated phenotypic change can occur. The results of this study will aid in developing strategies that work through imposing an ecological disadvantage on insect pests, which will be of great value for pest control in agricultural industry.


Assuntos
Enterobacteriaceae/genética , Resistência a Inseticidas/genética , Animais , Ásia , Bactérias/genética , DNA Bacteriano/genética , Hemípteros , Insetos/genética , Resistência a Inseticidas/fisiologia , Inseticidas , Polimorfismo de Nucleotídeo Único/genética , Simbiose/genética
19.
Pestic Biochem Physiol ; 173: 104777, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33771256

RESUMO

Ceratocystis fimbriata is the pathogen of black rot disease, which widely exists in sweet potato producing areas all over the world. The antifungal activity of volatile organic compounds (VOCs) released by Pseudomonas chlororaphis subsp. aureofaciens SPS-41 against C. fimbriata was reported in our previous study. In this study, we attempted to reveal the underlying antifungal mechanism of SPS-41 volatiles. Our results showed that the VOCs released by SPS-41 caused the morphological change of hyphae, destroyed the integrity of cell membrane, reduced the content of ergosterol, and induced massive accumulation of reactive oxygen species in C. fimbriata cells. Furthermore, SPS-41 fumigation decreased the mitochondrial membrane potential, acetyl-CoA and pyruvate content of C. fimbriata cells, as well as the mitochondrial dehydrogenases activity. In addition, the VOCs generated by SPS-41 reduced the intracellular ATP content and increased the extracellular ATP content of C. fimbriata. In summary, SPS-41 fumigation exerted its antifungal activity by inducing oxidative stress and mitochondrial dysfunction in C. fimbriata.


Assuntos
Ascomicetos , Compostos Orgânicos Voláteis , Antifúngicos/farmacologia , Ceratocystis , Mitocôndrias , Estresse Oxidativo , Doenças das Plantas , Pseudomonas , Compostos Orgânicos Voláteis/farmacologia
20.
J Environ Manage ; 289: 112525, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33836438

RESUMO

In this study, a novel halotolerant phenol-degrading yeast strain, SDP-1, was isolated from a coastal soil in Jiangsu, China, and identified as Candida tropicalis by morphology and rRNA internal transcribed space region sequence analysis. Strain SDP-1 can efficiently remove phenol at wide ranges of pH (3.0-9.0), temperature (20-40 °C), and NaCl (0-5%, w/v), as well as the tolerance of Mn2+, Zn2+ and Cr3+ in aquatic phase. It also utilized multiple phenol derivatives and aromatic hydrocarbons as sole carbon source and energy for growth. Free cells of SDP-1 were able to degrade the maximum phenol concentration of 1800 mg/L within 56 h under the optimum culture conditions of 10% inoculum volume, pH 8.0, 35 °C and 200 rpm agitation speed. Meanwhile, SDP-1 was immobilized on sodium alginate, and the capability of efficiently phenol degradation of free cells and immobilized SDP-1 were evaluated. Shortened degradation time and long-term utilization and recycling for immobilized SDP-1 was achieved compared to free cells. The 1200 mg/L of phenol under 5% NaCl stress could be completely degraded within 40 h by immobilized cells. In actual industrial coking wastewater, immobilized cells were able to completely remove 383 mg/L phenol within 20 h, and the corresponding chemical oxygen demand (COD) value was decreased by 50.38%. Besides, in phenol-contained salinity soil (3% NaCl), 100% of phenol (500 and 1000 mg/kg) removal efficiency was achieved by immobilized SDP-1 within 12 and 26 days, respectively. Our study suggested that versatile yeast Candida tropicalis SDP-1 could be potentially used for enhanced treatment of phenol-contaminated wastewater and soil under hypersaline or no-salt environmental conditions.


Assuntos
Fenol , Águas Residuárias , Biodegradação Ambiental , Candida tropicalis/genética , China , Fenóis , Salinidade , Solo
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