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1.
Huan Jing Ke Xue ; 44(11): 6412-6420, 2023 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-37973122

RESUMO

Industrial parks are the main carriers of industrial activities and are also key areas for carbon emissions. To deeply explore the decoupling state of carbon emissions and economic development of industrial parks and the driving forces, Zhengzhou Economic Development Zone were taken as example, based on the energy consumption data of industrial enterprises above a designated size from 2011 to 2020, the IPCC carbon emission accounting method, Tapio decoupling model, and logarithmic mean Divisia index decomposition method were used to analyze the characteristics of carbon emissions from energy consumption in the park, the relationship between carbon emissions and economic development, and the driving factors of decoupling. The results showed that:① in terms of carbon emission characteristics, the carbon emissions of energy consumption in Zhengzhou Economic Development Zone were mainly indirect carbon emissions, and the total carbon emissions showed a trend of rapid growth in the early stage, slowing down in the medium term, and negative growth in the later stage. The carbon emission intensity was decreasing annually. ② From the perspective of decoupling, the decoupling index between total carbon emissions and economic development in Zhengzhou Economic Development Zone from 2011 to 2016 was 1.021, which was in a state of growth linkage, and the decoupling index decreased to 0.089 from 2016 to 2020, turning into a weak decoupling state. ③ From the analysis of driving factors, from 2011 to 2016, four factors, namely carbon emission coefficient, energy efficiency, industrial structure, and economic level, all had a restraining effect on the decoupling of carbon emissions in Zhengzhou Economic Development Zone, and from 2016 to 2020, they all turned into promotion except for the economic level. This study showed that among the factors for the decoupling of carbon emissions in the Zhengzhou Economic Development Zone, the economic level played a major inhibitory role, and energy efficiency played a major role in promoting it. The results of this study can provide a reference for the industry-city integrated industrial park represented by Zhengzhou Economic Development Zone to formulate corresponding carbon emission reduction policies and achieve the carbon peaking and carbon neutrality goals.

2.
Virol J ; 18(1): 122, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108000

RESUMO

Using viral metagenomics, viral nucleic acid in 30 respiratory secretion samples collected from children with unknown etiological acute respiratory disease were investigated. Sequences showing similarity to human parainfluenza virus 1, anellovirus, bocavirus, coxsackievirus A4, human parechovirus (HPeV), and alphaflexivirus were recovered from these samples. Complete genomes of one anellovirus, one coxsackievirus A4, three parechoviruses were determined from these libraries. The anellovirus (MW267851) phylogenetically clustered with an unpublished anellovirus (MK212032) from respiratory sample of a Vietnamese patient, forming a separate branch neighboring to strains within the genus Betatorquevirus. The genome of coxsackievirus A4 (MW267852) shares the highest sequence identity of 96.4% to a coxsackievirus A4 (MN964079) which was identified in clinical samples from children with Hand, Foot, and Mouth Disease (HFMD). Two (MW267853 and MW267854) of the three parechoviruses belong to HPeV-1 and the other one (MW267855) belongs to HPeV-6. Recombination analysis indicated that an HPeV-1 (MW267854) identified in this study is a putative recombinant occurred between HPeV-1 and HPeV-3. Whether these viruses have association with specific respiratory disease calls for further investigation.


Assuntos
Parechovirus , Infecções por Picornaviridae , Doenças Respiratórias , Viroma , Criança , Genoma Viral , Humanos , Parechovirus/genética , Filogenia , Infecções por Picornaviridae/diagnóstico , RNA Viral , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/virologia , Análise de Sequência de DNA
3.
Front Plant Sci ; 7: 710, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27252725

RESUMO

Exogenous ethylene, or ethephon, has been widely used to induce pineapple flowering, but the molecular mechanism behind ethephon induction is still unclear. In this study, we cloned four genes encoding ethylene receptors (designated AcERS1a, AcERS1b, AcETR2a, and AcETR2b). The 5' flanking sequences of these four genes were also cloned by self-formed adaptor PCR and SiteFinding-PCR, and a group of putative cis-acting elements was identified. Phylogenetic tree analysis indicated that AcERS1a, AcERS1b, AcETR2a, and AcETR2b belonged to the plant ERS1s and ETR2/EIN4-like groups. Quantitative real-time PCR showed that AcETR2a and AcETR2b (subfamily 2) were more sensitive to ethylene treatment compared with AcERS1a and AcERS1b (subfamily 1). The relative expression of AcERS1b, AcETR2a, and AcETR2b was significantly increased during the earlier period of pineapple inflorescence formation, especially at 1-9 days after ethylene treatment (DAET), whereas AcERS1a expression changed less than these three genes. In situ hybridization results showed that bract primordia (BP) and flower primordia (FP) appeared at 9 and 21 DAET, respectively, and flowers were formed at 37 DAET. AcERS1a, AcERS1b, AcETR2a, and AcETR2b were mainly expressed in the shoot apex at 1-4 DAET; thereafter, with the appearance of BP and FP, higher expression of these genes was found in these new structures. Finally, at 37 DAET, the expression of these genes was mainly focused in the flower but was also low in other structures. These findings indicate that these four ethylene receptor genes, especially AcERS1b, AcETR2a, and AcETR2b, play important roles during pineapple flowering induced by exogenous ethephon.

4.
Molecules ; 19(6): 8518-32, 2014 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-24959679

RESUMO

The fruit physico-chemical properties, antioxidant activity and mineral contents of 26 pineapple [Ananas comosus (L.) Merr.] genotypes grown in China were measured. The results showed great quantitative differences in the composition of these pineapple genotypes. Sucrose was the dominant sugar in all 26 genotypes, while citric acid was the principal organic acid. Potassium, calcium and magnesium were the major mineral constituents. The ascorbic acid (AsA) content ranged from 5.08 to 33.57 mg/100 g fresh weight (FW), while the total phenolic (TP) content varied from 31.48 to 77.55 mg gallic acid equivalents (GAE)/100 g FW. The two parameters in the predominant cultivars Comte de Paris and Smooth Cayenne were relative low. However, MD-2 indicated the highest AsA and TP contents (33.57 mg/100 g and 77.55 mg GAE/100 g FM, respectively), and it also showed the strongest antioxidant capacity 22.85 and 17.30 µmol TE/g FW using DPPH and TEAC methods, respectively. The antioxidant capacity of pineapple was correlated with the contents of phenolics, flavonoids and AsA. The present study provided important information for the further application of those pineapple genotypes.


Assuntos
Ananas/química , Antioxidantes/análise , Carboidratos/análise , Minerais/análise , Ananas/classificação , Ananas/genética , Ácido Ascórbico/análise , Cálcio/análise , China , Ácido Cítrico/análise , Flavonoides/análise , Genótipo , Magnésio/análise , Fenóis/análise , Potássio/análise , Sacarose/análise
5.
Blood Transfus ; 12(2): 238-43, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23399369

RESUMO

BACKGROUND: Despite the introduction of anti-D prophylaxis into clinical practice, RhD alloimmunisation remains a problem, particularly in the context of transfusions and pregnancy-induced alloimmunisation. The incidence of RhD alloimmunisation among phenotypically RhD-negative individuals is unknown in most countries. We investigated RhD alloimmmunisation in RhD-negative pregnant women and transfusion recipients in south-east China in order to optimise the prevention of this phenomenon. METHODS: We analysed the RhD alloimmunisation status of RhD-negative pregnant women and transfusion recipients in south-east China. The RhD blood types of the study population were identified by standard serological methods. The D antigen was further tested with the indirect antiglobulin test to exclude or confirm weak D or partial D types. RhC, c, E and e antigens were typed in all subjects. If anti-D antibody screening was positive, the specificity and titre of the antibody were determined. The Del phenotype was investigated by the polymerase chain reaction sequence-specific primer method. RESULTS: An anti-D antibody was found in 61 of 416 RhD-negative pregnant women (14.66%), and in 11 of 227 RhD-negative transfusion recipients (4.85%). None of the 72 RhD-negative pregnant women or transfusion recipients with anti-D had the Del phenotype. Anti-D antibodies were not detected among Del phenotype individuals and Del phenotypes were not found in anti-D antibody producing individuals. DISCUSSION: Our study suggests that the risk of alloimmunity-induced neonatal haemolysis increases in true RhD-negative multipara. Perinatal protection would be necessary in these patients, while antenatal anti-D testing and Rh immune globulin prophylaxis would be unnecessary for RhDel pregnant women. Pregnant women and transfusion recipients with the Del type seldom produce anti-D antibody. RhD-negative recipients are not at risk of alloimmunisation after transfusion with Del red blood cells.


Assuntos
Isoanticorpos/sangue , Complicações na Gravidez , Isoimunização Rh , Sistema do Grupo Sanguíneo Rh-Hr/sangue , Reação Transfusional , Adulto , China , Feminino , Humanos , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/prevenção & controle , Isoimunização Rh/sangue , Isoimunização Rh/epidemiologia , Isoimunização Rh/prevenção & controle , Imunoglobulina rho(D)
6.
Blood Transfus ; 12(2): 244-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24333082

RESUMO

BACKGROUND: The characteristics of the D antigen are important as they influence the immunogenicity of D variant cells. Several studies on antigenic sites have been reported in normal D positive, weak D and partial D cases, including a comprehensive analysis of DEL types in Caucasians. The aim of this study was to assess D antigen density and epitopes on the erythrocyte surface of Asian type DEL phenotypic individuals carrying the RHD1227A allele in the Chinese population. MATERIALS AND METHODS: A total of 154 DEL phenotypic individuals carrying the RHD1227A allele were identified through adsorption and elution tests and polymerase chain reaction analysis with sequence-specific primers in the Chinese population. D antigen density on the erythrocyte surface of these individuals was detected using a flow cytometric method. An erythrocyte sample with known D antigen density was used as a standard. Blood samples from D-negative and D-positive individuals were used as controls. In addition, D antigen epitopes on the erythrocyte surface of DEL individuals carrying the RHD1227A allele were investigated with 18 monoclonal anti-D antibodies specific for different D antigen epitopes. RESULTS: The means of the median fluorescence intensity of D antigen on the erythrocyte membrane surface of D-negative, D-positive and DEL individuals were 2.14±0.25, 193.61±11.43 and 2.45±0.82, respectively. The DEL samples were estimated to have approximately 22 D antigens per cell. The samples from all 154 DEL individuals reacted positively with 18 monoclonal anti-D antibodies specific for different D antigen epitopes. DISCUSSION: In this study, D antigen density on the erythrocyte surface of DEL individuals carrying the RHD1227A allele was extremely low, there being only very few antigenic molecules per cell, but the D antigen epitopes were grossly complete.


Assuntos
Alelos , Epitopos/metabolismo , Eritrócitos/metabolismo , Sistema do Grupo Sanguíneo Rh-Hr/metabolismo , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Epitopos/genética , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Sistema do Grupo Sanguíneo Rh-Hr/genética
7.
Int J Mol Sci ; 13(8): 9460-9477, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22949808

RESUMO

Differences in carbohydrate contents and metabolizing-enzyme activities were monitored in apical, medial, basal and core sections of pineapple (Ananas comosus cv. Comte de paris) during fruit development and ripening. Fructose and glucose of various sections in nearly equal amounts were the predominant sugars in the fruitlets, and had obvious differences until the fruit matured. The large rise of sucrose/hexose was accompanied by dramatic changes in sucrose phosphate synthase (SPS) and sucrose synthase (SuSy) activities. By contrast, neutral invertase (NI) activity may provide a mechanism to increase fruit sink strength by increasing hexose concentrations. Furthermore, two cDNAs of Ac-sps (accession no. GQ996582) and Ac-ni (accession no. GQ996581) were first isolated from pineapple fruits utilizing conserved amino-acid sequences. Homology alignment reveals that the amino acid sequences contain some conserved function domains. Transcription expression analysis of Ac-sps, Ac-susy and Ac-ni also indicated distinct patterns related to sugar accumulation and composition of pineapple fruits. It suggests that differential expressions of multiple gene families are necessary for sugar metabolism in various parts and developmental stages of pineapple fruit. A cycle of sucrose breakdown in the cytosol of sink tissues could be mediated through both Ac-SuSy and Ac-NI, and Ac-NI could be involved in regulating crucial steps by generating sugar signals to the cells in a temporally and spatially restricted fashion.


Assuntos
Ananas/metabolismo , Metabolismo dos Carboidratos/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/metabolismo , Sacarose/metabolismo , beta-Frutofuranosidase/metabolismo , Sequência de Aminoácidos , Ananas/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Genes de Plantas , Glucosiltransferases/genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Homologia de Sequência de Aminoácidos , beta-Frutofuranosidase/genética
8.
Int J Mol Sci ; 13(6): 7383-7392, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22837701

RESUMO

Volatile compounds from two pineapples varieties (Tainong No.4 and No.6) were isolated by headspace solid phase microextraction (HS-SPME) and identified and quantified by gas chromatography-mass spectrometry (GC/MS). In the Tainong No. 4 and No. 6 pineapples, a total of 11 and 28 volatile compounds were identified according to their retention time on capillary columns and their mass spectra, and quantified with total concentrations of 1080.44 µg·kg(-1) and 380.66 µg·kg(-1) in the Tainong No.4 and No. 6 pineapples, respectively. The odor active values (OAVs) of volatile compounds from pineapples were also calculated. According to the OAVs, four compounds were defined as the characteristic aroma compounds for the Tainong No. 4 pineapple, including furaneol, 3-(methylthio)propanoic acid methyl ester, 3-(methylthio)propanoic acid ethyl ester and δ-octalactone. The OAVs of five compounds including ethyl-2-methylbutyrate, methyl-2-methylbutyrate, 3-(methylthio)propanoic acid ethyl ester, ethyl hexanoate and decanal were considered to be the characteristic aroma compounds for the Tainong No. 6 pineapple.


Assuntos
Ananas/química , Compostos Orgânicos Voláteis/análise , China , Cromatografia Gasosa-Espectrometria de Massas/métodos
9.
Plant Physiol Biochem ; 55: 33-42, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22522578

RESUMO

Polar auxin transport (PAT) plays an important role in the adventitious root formation of mango cotyledon segments, but the molecular mechanism remains unclear. In this study, we cloned a gene encoding an auxin efflux carrier (designated as MiPIN1), and we cloned four genes encoding auxin influx carriers (designated as MiAUX1, MiAUX2, MiAUX3 and MiAUX4). The results of a phylogenetic tree analysis indicated that MiPIN1 and the MiAUXs belong to plant PIN and AUXs/LAXs groups. Quantitative real-time PCR indicated that the expression of MiPIN1 and the MiAUXs was lowest at 0 days but sharply increased on and after day 4. During the root formation in the mango cotyledon segments, the MiPIN1 expression in the distal cut surface (DCS) was always higher than the expression in the proximal cut surface (PCS) whereas the expression of the MiAUXs in the PCS was usually higher than in the DCS. This expression pattern might be result in the PAT from the DCS to the PCS, which is essential for the adventitious root formation in the PCS. Our previous study indicated that a pre-treatment of embryos with indole-3-butyric acid (IBA) significantly promoted adventitious rooting in PCS whereas a pre-treatment with 2,3,5-triiodobenzoic acid (TIBA) completely inhibited this rooting. In this study, however, IBA and TIBA pre-treatments slightly changed the expression of MiPIN1. In contrast, while the MiAUX3 and MiAUX4 expression levels were significantly up-regulated by the IBA pre-treatment, the expression levels were down-regulated by the TIBA pre-treatment. These findings imply that MiAUX3 and MiAUX4 are more sensitive to the IBA and TIBA treatments and that they might play important roles during adventitious root formation in mango cotyledon segments.


Assuntos
Cotilédone/genética , Ácidos Indolacéticos/metabolismo , Mangifera/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Transporte Biológico , Clonagem Molecular , Cotilédone/crescimento & desenvolvimento , Cotilédone/metabolismo , DNA Complementar/química , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Mangifera/crescimento & desenvolvimento , Mangifera/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
10.
Int J Mol Sci ; 13(1): 1039-1053, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22312303

RESUMO

PISTILLATA (PI)-like genes are crucial regulators of flowering in angiosperms. A homologue of PI, designated as AcPI (Genbank accession number HQ717796), was isolated from pineapple cultivar Comte de Paris by reverse transcriptase polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The cDNA sequence of AcPI is 907 bp in length and contains an open reading frame of 594 bp, which encodes a protein of 197 amino acids. The molecular weight was 2.29 kDa and the isoelectric point was 9.28. The alignment showed that AcPI had a high identity with CsPIC2 (78.6%), AoPI (77.4%), OrcPI (75.7%) and HPI2 (72.4%). Quantitative real-time polymerase chain reaction (qRT-PCR) analyses in different tissues showed that the expression pattern of AcPI was different from the B-class genes in eudicots. AcPI was expressed in all the tissues investigated. The expression level was very low in fruit stems, bracts, leaves and sepals, high in petals and carpels, and moderate in apical meristems, flesh and stamens. The qRT-PCR analyses in different stages indicated that the expression of AcPI reached the highest level at 40 days after flower inducement, when the multiple fruit and floral organs were forming. It proved the important role of AcPI in floral organs and fruit development. The 35S::AcPI transgenic Arabidopsis plants flowered earlier and had more inflorescences or branches than wild type plants.


Assuntos
Ananas/metabolismo , Clonagem Molecular , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , DNA Complementar/metabolismo , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
11.
Molecules ; 16(6): 5104-12, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21694674

RESUMO

Characteristic aroma volatile compounds from different parts of cayenne pineapple were analyzed by headspace-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC/MS). The main volatile compounds were esters, terpenes, ketones and aldehydes. The number and content of aroma compounds detected in pulp were higher than those found in core. In pulp, the characteristic aroma compounds were ethyl 2-methylbutanoate, ethyl hexanoate, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF), decanal, ethyl 3-(methylthio)propionate, ethyl butanoate, and ethyl (E)-3-hexenoate; while in core the main compounds were ethyl 2-methylbutanoate, ethyl hexanoate and DMHF. The highest odor units were found to correspond to ethyl 2-methylbutanoate, followed by ethyl hexanoate and DMHF. The odor units found for pulp were higher than those for core.


Assuntos
Ananas/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise
12.
Artigo em Chinês | MEDLINE | ID: mdl-21055323

RESUMO

OBJECTIVE: To explore the influence of histamine H3 receptor agonist, IMETIT and simultaneous use of IMETIT and H1-receptor antagonist, Loratadine, on the symptoms of allergic rhinitis (AR) and substance P(SP) secretion and expression of SP receptor (SP-R) mRNA in AR model in guinea pigs. METHODS: Guinea pigs were divided randomly into 4 groups: AR group (group A), IMETIT group (group B), Loratadine group (group C) and IMETIT+Loratadine group (group D). The severity of AR was assessed by determining the extent of three markers of allergic symptoms (sneezing, nasal rubbing and nose blocking). The changes in the nasal mucosa were studied by pathological methods. The expression of positive cell of SP was detected by immunohistochemistry. SP-R mRNA expression in nasal mucosa was used to do reverse transcriptive-polymerase chain reaction (RT-PCR). Statistical analysis was performed using a SPSS 13.0 software. RESULTS: In Group B, the mean (x ± s) number of sneeze [(15.0 ± 1.3) times], scratching nose [(16.5 ± 2.3) times] and respiratory frequency [(76.3 ± 4.1) times/min] were significantly improved than those in group A [(23.5 ± 2.6) times, (26.1 ± 4.1) times and (66.5 ± 5.8) times/min, respectively), P value were 0.000, 0.000 and 0.001, respectively]. The numbers of SP-positive cells [(11.6 ± 3.6)/HP] and SP-R mRNA expression (0.64 ± 0.04) in group B were reduced significantly compared to group A [(27.1 ± 9.7)/HP, (0.83 ± 0.03), P value were 0.000, 0.000, respectively]. Sneeze [(10.0 ± 2.3) times], scratching nose [(11.8 ± 1.7) times] and respiration [(90.0 ± 5.0) times/min] in Group D were improved significantly than those in group B (P value were 0.000, 0.002 and 0.000, respectively). SP-positive cells [(2.0 ± 1.7)/HP] and SP-R mRNA expression (0.52 ± 0.06) in Group D compared with group B were also significantly reduced (P value were 0.012 and 0.000, respectively). Pathological changes in guinea pig nasal mucosa in group B, group D were alleviated than those in group A. The combination of IMETIT and Loratadine had a synergistic effect on these effects (F value were 11.59, 8.28, 5.61, 5.48, 6.50, respectively, P value were 0.002, 0.008, 0.025, 0.027, 0.017). CONCLUSIONS: IMETIT and the combination of IMETIT with Loratadine can effectively relieve the symptoms of AR in guinea pigs, its mechanism may be relevant to reduce SP secretion and the expression of SP-R mRNA, and the two has a synergistic effect. It may be useful as a novel therapeutic approach in nasal allergy.


Assuntos
Agonistas dos Receptores Histamínicos/farmacologia , Imidazóis/farmacologia , Receptores da Neurocinina-1/metabolismo , Rinite Alérgica Perene/metabolismo , Substância P/metabolismo , Tioureia/análogos & derivados , Animais , Feminino , Cobaias , Agonistas dos Receptores Histamínicos/uso terapêutico , Imidazóis/uso terapêutico , Loratadina/farmacologia , Loratadina/uso terapêutico , Masculino , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/metabolismo , RNA Mensageiro/metabolismo , Receptores da Neurocinina-1/genética , Substância P/genética , Tioureia/farmacologia , Tioureia/uso terapêutico
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(7): 1934-8, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20828003

RESUMO

The combinational-stimulated bands were used to develop linear and nonlinear calibrations for the early detection of sclerotinia of oilseed rape (Brassica napus L.). Eighty healthy and 100 Sclerotinia leaf samples were scanned, and different preprocessing methods combined with successive projections algorithm (SPA) were applied to develop partial least squares (PLS) discriminant models, multiple linear regression (MLR) and least squares-support vector machine (LS-SVM) models. The results indicated that the optimal full-spectrum PLS model was achieved by direct orthogonal signal correction (DOSC), then De-trending and Raw spectra with correct recognition ratio of 100%, 95.7% and 95.7%, respectively. When using combinational-stimulated bands, the optimal linear models were SPA-MLR (DOSC) and SPA-PLS (DOSC) with correct recognition ratio of 100%. All SPA-LSSVM models using DOSC, De-trending and Raw spectra achieved perfect results with recognition of 100%. The overall results demonstrated that it was feasible to use combinational-stimulated bands for the early detection of Sclerotinia of oilseed rape, and DOSC-SPA was a powerful way for informative wavelength selection. This method supplied a new approach to the early detection and portable monitoring instrument of sclerotinia.


Assuntos
Ascomicetos , Brassica napus/microbiologia , Doenças das Plantas/microbiologia , Espectroscopia de Luz Próxima ao Infravermelho , Algoritmos , Calibragem , Análise dos Mínimos Quadrados , Modelos Lineares , Modelos Teóricos , Folhas de Planta/microbiologia , Máquina de Vetores de Suporte
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(1): 62-5, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20302082

RESUMO

Near infrared (NIR) spectroscopy combined with variable selection method of modeling power was investigated for the fast and accurate geographical origin discrimination of auricularia auricula. A total of 240 samples of auriculari auricula were collected in the market, and the spectra of all samples were scanned within the spectral region of 1100-2500 nm. The calibration set was composed of 180 (45 samples for each origin) samples, and the remaining 60 samples were employed as the validation set. The optimal partial least squares (PLS) discriminant model was achieved after performance comparison of different preprocessing (Savitzky-Golay smoothing, standard normal variate, 1-derivative, and 2-derivative). The effective wavelengths, which were selected by modeling power (MP) and used as input data matrix of least squares-support vector machine (LS-SVM), were employed for the development of modeling power-least squares-support vector machine (MP-LS-SVM) model. Radial basis function (RBF) kernel was applied as kernel function. Three threshold methods for variable selection by modeling power were applied in MP-LSSVM models, and there were the values of modeling power higher than 0.95, higher than 0.90, and higher than 0.90 combined with peak location (0.90+Peak). The correct recognition ratio in the validation set was used as evaluation standards. The absolute error of prediction was set as 0.1, 0.2 and 0.5, which showed the wrong recognition threshold value. The results indicated that the MP-LS-SVM (0.90+Peak) model could achieve the optimal performance in all three absolute error standards (0.1, 0.2 and 0.5), and the correct recognition ratio was 98.3%, 100% and 100%, respectively. The variable selection threshold (0.90+Peak) was the most suitable one in the application of modeling power. It was concluded that modeling power was an effective variable selection method, and near infrared spectroscopy combined with MP-LS-SVM model was successfully applied for the origin discrimination of auricularia auricula, and an excellent prediction precision was also achieved.


Assuntos
Basidiomycota/classificação , Espectroscopia de Luz Próxima ao Infravermelho , Geografia , Análise dos Mínimos Quadrados , Modelos Estatísticos , Máquina de Vetores de Suporte
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(10): 2730-3, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-20038048

RESUMO

Site-specific variable pesticide application is one of the major precision crop production management operations. Rice blast is a severe threat for rice production. Traditional chemistry methods can do the accurate crop disease identification, however they are time-consuming, require being executed by professionals and are of high cost. Crop disease identification and classification by human sight need special crop protection knowledge, and is low efficient. To obtain fast, reliable, accurate rice blast disease information is essential for achieving effective site-specific pesticide applications and crop management. The present paper describes a multi-spectral leaf blast identification and classification image sensor, which uses three channels of crop leaf and canopy images. The objective of this work was to develop and evaluate an algorithm under simplified lighting conditions for identifying damaged rice plants by the leaf blast using digital color images. Based on the results obtained from this study, the seed blast identification accuracy can be achieved at 95%, and the leaf blast identification accuracy can be achieved at 90% during the rice growing season. Thus it can be concluded that multi-spectral camera can provide sufficient information to perform reasonable rice leaf blast estimation.


Assuntos
Oryza , Doenças das Plantas , Algoritmos , Praguicidas , Folhas de Planta
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(12): 3295-9, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20210154

RESUMO

Visible and near infrared (Vis-NIR) spectroscopy was used to fast and non-destructively classify the disease levels of rice panicle blast. Reflectance spectra between 325 and 1 075 nm were measured. Kennard-Stone algorithm was operated to separate samples into calibration and prediction sets. Different spectral pretreatment methods, including standard normal variate (SNV) and multiplicative scatter correction (MSC), were used for the spectral pretreatment before further spectral analysis. A hybrid wavelength variable selection method which is combined with uninformative variable elimination (UVE) and successive projections algorithm (SPA) was operated to select effective wavelength variables from original spectra, SNV pretreated spectra and MSC pretreated spectra, respectively. UVE was firstly operated to remove uninformative wavelength variables from the full-spectrum. Then SPA selected the effective wavelength variables with less colinearity after UVE. Least square-support vector machine (LS-SVM) was used as the calibration method for the spectral analysis in this study. The selected effective wavelengths were set as input variables of LS-SVM model. The LS-SVM model established based on SNV-UVE-SPA obtained the best results. Only six effective wavelengths (459, 546, 569, 590, 775 and 981 nm) were selected from the full-spectrum which has 600 wavelength variables by UVE-SPA, and their LS-SVM model's performance was further improved. For SNV-UVE-SPA-LS-SVM model, coefficient of determination for prediction set (R2(p)), root mean square error for prediction (RMSEP) and residual predictive deviation (RPD) were 0.979, 0.507 and 6.580, respectively. The overall results indicate that Vis-NIR spectroscopy is a feasible way to classify disease levels of rice panicle blast fast and non-destructively. UVE-SPA is an efficient variable selection method for the spectral analysis, and their selected effective wavelengths can represent the useful information of the full-spectrum and have higher signal/noise ratio and less colinearity.


Assuntos
Flores/microbiologia , Oryza/microbiologia , Doenças das Plantas/classificação , Espectroscopia de Luz Próxima ao Infravermelho , Algoritmos , Modelos Teóricos
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