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1.
Chemistry ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32162421

RESUMO

The metal-organic frameworks (MOFs) with long persistent luminescence (LPL) have caused widespread attention due to potential applications in displaying, anti-counterfeiting, and so on. However, MOF materials are often with large pore size, which restricts the formation of efficient inter- and intramolecular interactions to realize LPL. Herein, we report a new approach to achieve LPL in MOFs by multi-fold interpenetration of discrete frameworks. By the comparison between 3-fold and 2-fold interpenetrating MOFs, we found that the former with higher multiplicity and denser frameworks can be endowed with enhanced inter- and intramolecular interactions, and thus prolonged long persistent luminescence is obtained. Meanwhile, metal cluster and heavy halogen effect could also arouse variations in LPL durations and colours.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32212367

RESUMO

The borocarbonylative coupling of unactivated alkenes with alkyl halides remains a challenge. In this communication, a Cu-catalyzed borocarbonylative coupling of unactivated alkenes with alkyl halides for the synthesis of ß-boryl ketones has been developed. A broad range of ß-boryl ketone derivatives was prepared in moderate to excellent yields with complete regioselectivity.

3.
Chem Asian J ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32012458

RESUMO

Aggregation-induced emission (AIE) technology has been demonstrated to be a facile approach for in-situ monitoring atom transfer radical polymerization (ATRP). A series of tertraphenyl ethylene (TPE)-containing α-bromo compounds were synthesized and applied as ATRP initiators. The photoluminescent (PL) emission of the polymerization system is proved to be sensitive to the local viscosity owing to the AIE characteristics of TPE. Linear relationships between the resulting molecular weight Mn and PL intensity were observed in several polymerization systems with different monomers, indicating the variability of this technique. Compared to physical blending, the chemical bonding of the TPE group in the chain end has higher sensitivity and accuracy to the polymer segments and the surrounding environment. This work promoted the combination of the AIE technique and controlled living radical polymerization, and introduced such an optical research platform to the ATRP polymerization process.

4.
Virol J ; 17(1): 19, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32014014

RESUMO

BACKGROUND: Porcine parvovirus (PPV) and pseudorabies virus (PRV) are the important etiological agents of swine infectious diseases, resulting in huge economic losses to the Chinese swine industry. Interleukin-6 (IL-6) has the roles to support host immune response to infections as a pleiotropic cytokine. It is essential to construct a live attenuated vaccine-based recombinant PRV that expresses PPV VP2 protein and porcine IL-6 for prevention and control of PRV and PPV. METHODS: The recombinant plasmid, pGVP2-IL6, was constructed by porcine IL-6 gene substituting for EGFP gene of the PRV transfer plasmid pGVP2-EGFP containing VP2 gene of PPV. Plasmid pGVP2-IL6 was transfected into swine testicle cells pre-infected with the virus rPRV-VP2-EGFP strain through homologous recombination and plaque purification to generate a recombinant virus rPRV-VP2-IL6. The recombinant PRV was further identified by PCR and DNA sequencing, and the expression of the VP2 protein and porcine IL-6 was analyzed by reverse transcription-PCR (RT-PCR) and Western blot. The virus titer was calculated according to Reed and Muench method. The immunogenicity of the recombinant virus was preliminarily evaluated in mice by intramuscular administration twice with the rPRV-VP2-IL6 at 4-week intervals. RESULTS: A recombinant virus rPRV-VP2-IL6 was successfully constructed and confirmed in this study. The properties of rPRV-VP2-IL6 were similar to the parental virus HB98 in terms of growth curve, morphogenesis and virus plaque sizes, and rPRV-VP2-IL6 was proliferated in different cell types. It induced specific antibodies against PPV as well as a strong increase of PPV-specific lymphocyte proliferation responses in mice immunized with rPRV-VP2-IL6, and provided partial protection against the virulent PPV challenge. rPRV-VP2-IL6 also induced a high level of neutralizing antibodies against PRV, and significantly reduced the mortality rate of (1 of 10) following virulent PRV challenge compared with the control (10 of 10). CONCLUSIONS: The recombinant rPRV-VP2-IL6 might be a potential candidate vaccine against PRV and PPV infections in pigs.

6.
Clin Cardiol ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32032438

RESUMO

BACKGROUND: It was found that delayed activation wave often appeared in terminal QRS wave in non-ST-elevated myocardial infarction (NSTEMI) with culprit vessel in left circumflex artery (LCX), yet little is known about the similarities among non-"N"-wave non-ST-elevated myocardial infarction (N-NSTEMI) and ST-elevated myocardial infarction (STEMI). HYPOTHESIS: In AMI patients with the culprit vessel in LCX, "N" wave NSTEMI has a risk equivalent to STEMI. METHODS: All 874 patients admitted to Shenjing Hospital of China Medical University between January 1, 2013 and December 30, 2017 were included and whose coronary angiography (CAG) indicated the culprit vessel in LCX. Patients were divided into three groups: ST-elevated myocardial infarction group (STEMI group, n = 322), "N" wave non-ST-elevated myocardial infarction group (N-NSTEMI group, n = 232) and non-"N"-wave NSTEMI group (non N-NSTEMI group, n = 320). The basic data and the incidence of MACE during hospitalization and 12 months were analyzed. RESULTS: In STEMI and N-NSTEMI groups, AST, CK, CK-MB, TnI, and stenosis severity were significantly higher than non N-NSTEMI (P < .05). The lesions in the N-NSTEMI and STEMI groups were more often located proximal LCX before giving rise to OM1 of LCX (P < .05), however, the non N-NSTEMI group was often located distal LCX after giving rise to OM1 and the OM1 (P < .05). The incidence rates of all MACEs, all-cause death, ST, TVR, and rUAP were similar in N-NSTEMI and STEMI groups, which were greater than non N-NSTEMI (P < .05). Both N-NSTEMI and STEMI are independent risk factors for MACE (P < .05). CONCLUSION: The basic data and the incidence of major adverse cardiac event were similar in N-NSTEMI and STEMI patients, N-NSTEMI has a risk equivalent to acute STEMI.

7.
J Exp Bot ; 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32092145

RESUMO

Photosynthesis is currently measured using time laborious and/or destructive methods which slows research and breeding efforts to identify crop germplasm with higher photosynthetic capacities. We present a plot level screening tool for quantification of photosynthetic parameters and pigment contents that utilizes hyperspectral reflectance from sunlit leaf pixels collected from a plot (~2mx2m) in less than one minute. Using field grown Nicotiana tabacum with genetically altered photosynthetic pathways over two growing seasons (2017 and 2018), we built predictive models for eight photosynthetic parameters and pigment traits. Using partial least squares regression (PLSR) analysis of plot-level sunlit vegetative reflectance pixels from a single VNIR (400-900nm) hyperspectral camera, we predict maximum carboxylation rate of Rubisco (Vc,max , R2 =0.79) maximum electron transport rate in given conditions (J1800 , R2 = 0.59), maximal light saturated photosynthesis (Pmax , R2 = 0.54), chlorophyll content (Chl, R2 = 0.87), the ratio of chlorophyll a to b (Chl a:b, R2 = 0.63), carbon content (C, R2 = 0.47) and nitrogen content (N, R2 = 0.49). Model predictions did not improve when using two cameras spanning 400-1800nm suggesting a robust, widely applicable and more 'cost-effective' pipeline requiring only a single VNIR camera. The analysis pipeline and methods can be used in any cropping system with modified species specific PLSR analysis to offer a high throughput field phenotyping screening for germplasm with improved photosynthetic performance in field trials.

8.
Nanoscale ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32068219

RESUMO

A structurally stable stacked multilayer carbonitride is predicted with the aid of ab initio calculations. This carbonitride consists of C3N tetrahedra, and is similar to T-carbon and thus named T-C3N. Its 2-dimensional (2D) monolayer is also carefully investigated in this work. The studies on electronic properties reveal that bulk and 2D T-C3N are insulators with a 5.542 eV indirect band gap and a 5.741 eV direct band gap, respectively. However, the monolayer T-C3N exhibits an excellent uniform porosity. Its 5.50 Å pore size is perfect for water nanofiltration. The adsorption and permeation of water molecules on the monolayer T-C3N are investigated. Its promising potential application in highly efficient nanofiltration membranes for seawater desalination is discussed.

9.
Int J Biol Macromol ; 146: 497-507, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923489

RESUMO

Cyclic GMP-AMP (cGAMP) synthase (cGAS) is a predominant DNA sensor inducing the activation of the innate immune responses that produce proinflammatory cytokines and type I interferons, which has been well-investigated in mammals. However, chicken cGAS (chcGAS), which participates in avian innate immunity, has not been well-investigated. Here, we cloned the complete open reading frame sequence of chcGAS. Multiple sequence alignment and phylogenetic analysis revealed that chcGAS was homologous to mammalian cGAS. The chcGAS mRNA was highly expressed in the bone marrow and ileum. The subcellular localization of chcGAS was mainly in the cytoplasm, and partial co-localization was observed in the endoplasmic reticulum. Through overexpression and RNA interference, we demonstrated that chcGAS responded to exogenous dsDNA, HS-DNA, and poly(dA:dT), and to self dsDNA from the DNA damage response, thereby triggering the activation of STING/TBK1/IRF7-mediated innate immunity in both chicken embryonic fibroblasts and chicken liver cancer cells. Furthermore, downregulation of chcGAS enhanced the infection of fowl adenovirus serotype 4 in LMH cells. Our results demonstrated that chcGAS was an important cytosolic DNA sensor activating innate immune responses and may shed light on a strategy for preventing infectious diseases in the poultry industry.

10.
Ann Bot ; 125(4): 677-690, 2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-31922527

RESUMO

BACKGROUND AND AIMS: Hosting several global biodiversity hotspots, the region of the Qinghai-Tibetan Plateau (QTP) is exceptionally species-rich and harbours a remarkable level of endemism. Yet, despite a growing number of studies, factors fostering divergence, speciation and ultimately diversity remain poorly understood for QTP alpine plants. This is particularly the case for the role of hybridization. Here, we explored the evolutionary history of three closely related Gentiana endemic species, and tested whether our results supported the mountain geo-biodiversity hypothesis (MGH). METHODS: We genotyped 69 populations across the QTP with one chloroplast marker and 12 nuclear microsatellite loci. We performed phylogeographical analysis, Bayesian clustering, approximate Bayesian computation and principal components analysis to explore their genetic relationship and evolutionary history. In addition, we modelled their distribution under different climates. KEY RESULTS: Each species was composed of two geographically distinct clades, corresponding to the south-eastern and north-western parts of their distribution. Thus Gentiana veitchiorum and G. lawrencei var. farreri, which diverged recently, appear to have shared at least refugia in the past, from which their range expanded later on. Indeed, climatic niche modelling showed that both species went through continuous expansion from the Last Interglacial Maximum to the present day. Moreover, we have evidence of hybridization in the northwest clade of G. lawrencei var. farreri, which probably occurred in the refugium located on the plateau platform. Furthermore, phylogenetic and population genetic analyses suggested that G. dolichocalyx should be a geographically limited distinct species with low genetic differentiation from G. lawrencei var. farreri. CONCLUSIONS: Climatic fluctuations in the region of the QTP have played an important role in shaping the current genetic structure of G. lawrencei var. farreri and G. veitchiorum. We argue that a species pump effect did occur prior to the Last Interglacial Maximum, thus lending support to the MGH. However, our results do depart from expectations as suggested in the MGH for more recent distribution range and hybridization dynamics.

11.
Plant Cell Environ ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31922609

RESUMO

The lack of efficient means to accurately infer photosynthetic traits constrains understanding global land carbon fluxes and improving photosynthetic pathways to increase crop yield. Here, we investigated whether a hyperspectral imaging camera mounted on a mobile platform could provide the capability to help resolve these challenges, focusing on three main approaches, that is, reflectance spectra-, spectral indices-, and numerical model inversions-based partial least square regression (PLSR) to estimate photosynthetic traits from canopy hyperspectral reflectance for 11 tobacco cultivars. Results showed that PLSR with inputs of reflectance spectra or spectral indices yielded an R2 of ~0.8 for predicting V cmax and J max , higher than an R2 of ~0.6 provided by PLSR of numerical inversions. Compared with PLSR of reflectance spectra, PLSR with spectral indices exhibited a better performance for predicting V cmax (R2 = 0.84 ± 0.02, RMSE = 33.8 ± 2.2 µmol m-2 s-1 ) while a similar performance for J max (R2 = 0.80 ± 0.03, RMSE = 22.6 ± 1.6 µmol m-2 s-1 ). Further analysis on spectral resampling revealed that V cmax and J max could be predicted with ~10 spectral bands at a spectral resolution of less than 14.7 nm. These results have important implications for improving photosynthetic pathways and mapping of photosynthesis across scales.

12.
PeerJ ; 7: e8025, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799070

RESUMO

Chloroplasts are typically inherited from the female parent and are haploid in most angiosperms, but rare intra-individual heteroplasmy in plastid genomes has been reported in plants. Here, we report an example of plastome heteroplasmy and its characteristics in Gentiana tongolensis (Gentianaceae). The plastid genome of G. tongolensis is 145,757 bp in size and is missing parts of petD gene when compared with other Gentiana species. A total of 112 single nucleotide polymorphisms (SNPs) and 31 indels with frequencies of more than 2% were detected in the plastid genome, and most were located in protein coding regions. Most sites with SNP frequencies of more than 10% were located in six genes in the LSC region. After verification via cloning and Sanger sequencing at three loci, heteroplasmy was identified in different individuals. The cause of heteroplasmy at the nucleotide level in plastome of G. tongolensis is unclear from the present data, although biparental plastid inheritance and transfer of plastid DNA seem to be most likely. This study implies that botanists should reconsider the heredity and evolution of chloroplasts and be cautious with using chloroplasts as genetic markers, especially in Gentiana.

13.
Materials (Basel) ; 12(24)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817198

RESUMO

Based on the magneto-mechanical effect, the influence of crack size on stress evaluated with metal magnetic memory (MMM) technology was discussed in this paper. Based on equivalent theory, the regular rectangular grooves, with different widths and depths, were precut in the surface of an experimental sample for simulating surface crack, and a three dimensional electrically controlled displacement system was used to collect the Hp(y) signal of the sample under different stresses, and the fracture morphology was observed by using scanning electron microscopy (SEM). The results show that the influence of detection line on Hp(y) signal can be ignored; as stress increases, the Hp(y) signal turns counterclockwise around zero-crossing point and its mutation, corresponding to the location of groove, becomes distinct gradually. When groove depth is constant, the magnetic intensity gradient changes in the form of quadratic polynomial as groove width increases, and when the groove width is the same, the magnetic intensity gradient is a linear function of groove depth. When stress reaches the yield strength of the material, the magnetic intensity gradient decreases gradually as stress increases further, and the orientation of magnetic domain is seen as the main reason for that result. At last, the experimental results are discussed based on the piezomagnetic effect and leakage magnetic field theory of finite depth slit model, and the change of magnetic domain orientation is considered to be the main reason.

14.
J Nat Prod ; 82(12): 3504-3508, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31820976

RESUMO

Three new p-terphenyl derivatives, nocarterphenyls A-C (1-3), along with three known analogues (4-6) were isolated from the marine-derived actinobacterial strain Nocardiopsis sp. OUCMDZ-4936. Their structures were elucidated on the basis of spectroscopic analysis and a single-crystal X-ray diffraction experiment. Compounds 1 and 2 possess a benzothiazole and benzothiazine moiety, respectively, which are rare in the skeleton of p-terphenyls. Nocarterphenyl A (1) showed potent cytotoxic activity against the HL60 and HCC1954 cancer cell lines with the IC50 values of 0.38 and 0.10 µM among 26 human cancer cell lines.

15.
Carcinogenesis ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31740975

RESUMO

Gastric cancer remains one of the most lethal and prevalent malignancies, particularly in China. The majority of patients are diagnosed with gastric cancer at the late stages of the disease. Besides, the high relapse rate also contributes to the high mortality. Therefore, there exists an imperative need for the development of gastric cancer diagnostic techniques as well as novel indicators for gastric cancer metastasis. Exosomes, secreted by a variety of cell types, play critical roles in intercellular communication, which emerge as promising diagnostic biomarkers for gastric cancer. In this study, we present for the first time, at least to the best of our knowledge, the small RNA sequencing spectra of exosomes derived from the gastric cancer patient plasma using next-generation sequencing, focusing on the exploration of metastasis-related biomarkers. The exosomes enriched from patient plasma samples were well characterized by western blotting, transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). In the following bioinformatic analysis of exosomal miRNAs, three candidates were proposed as the biomarkers for metastasis of gastric cancer, namely miR-10b-5p, miR-101-3p, and miR-143-5p for gastric cancer with lymph node metastasis, gastric cancer with ovarian metastasis, and gastric cancer with liver metastasis, respectively. RT-qPCR was performed to test the accuracy of these candidates for validation. In conclusion, we successfully isolated and purified exosomes from plasma of patients with gastric cancer, and identified several potential exosomal miRNA markers to distinguish gastric cancer patients with various kinds of metastasis.

16.
Nanoscale Res Lett ; 14(1): 342, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712915

RESUMO

Converting solar energy into sustainable hydrogen fuel by photoelectrochemical (PEC) water splitting is a promising technology to solve increasingly serious global energy supply and environmental issues. However, the PEC performance based on TiO2 nanomaterials is hindered by the limited sunlight-harvesting ability and its high recombination rate of photogenerated charge carriers. In this work, layered SnS2 absorbers and CoOx nanoparticles decorated two-dimensional (2D) TiO2 nanosheet array photoelectrode have been rationally designed and successfully synthesized, which remarkably enhanced the PEC performance for water splitting. As the result, photoconversion efficiency of TiO2/SnS2/CoOx and TiO2/SnS2 hybrid photoanodes increases by 3.6 and 2.0 times under simulated sunlight illumination, compared with the bare TiO2 nanosheet arrays photoanode. Furthermore, the TiO2/SnS2/CoOx photoanode also presented higher PEC stability owing to CoOx catalyst served as efficient water oxidation catalyst as well as an effective protectant for preventing absorber photocorrosion.

17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(5): 663-666, 2019 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-31699197

RESUMO

Objective To compare the predictive value of different ratio measurement in predicting the risk of malignant thyroid nodules and to determine the best value of ratio in diagnosing thyroid nodules.Methods The clinical data of 342 thyroid nodules diagnosed by ultrasonography and confirmed by histology in our hospital from January 2018 to August 2018 were analyzed.The ratio of nodules in different sections,including longitudinal plane ratio(A/TL)and transverse plane ratio(A/TC),was obtained through the maximum head-foot diameter(TL),the maximum left-right diameter(TC),and the anterior-posterior diameter(A)of transverse section measured by ultrasonography.The correlation of histological diagnosis of benign or malignant nodule with longitudinal ratio and transverse ratio were analyzed.Results The A/TC and A/TL of malignant nodules were 1.00(0.83,1.17)and 0.81(0.65,1.00),respectively,which were significantly higher than those of benign nodules [0.81(0.67,0.93)(Z=-6.567,P=0.000)and 0.63(0.52,0.75)(Z=-7.239,P=0.000)].The area under the ROC curve of A/TC and A/TL was 0.734 and 0.712,respectively,showing no significant difference(area difference:0.0210,standard error:0.0213,95% CI:-0.0207-0.0627,Z=0.987,P=0.3235).The threshold values of A/TC and A/TL for predicting malignant nodules were 0.784 161 5 and 0.985 714 5,respectively.Conclusions Both A/TL and A/TC has similar diagnostic value in predicting the risk of malignant nodules.The best cutoff value of the above two ratios are 0.78 and 0.99 respectively.


Assuntos
Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Curva ROC , Medição de Risco , Sensibilidade e Especificidade , Ultrassonografia
18.
Bull Environ Contam Toxicol ; 103(5): 756-762, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31583424

RESUMO

The current study investigated the efficiency and mechanisms of in situ immobilization of artificially Cd-contaminated soils with ferronickel slag (FNS). The available Cd content of soil was measured and the modified European Community Bureau of Reference (BCR) sequential extraction procedure (SEP) was adopted to quantify the evolutions of Cd chemical speciation after the immobilization by the FNS. The results showed that the addition of FNS (5%‒15%) remarkably reduced the available Cd content and increased the pH and cation exchange capacity of soils. The passivation rate of Cd increased from 58.13% to 73.25% as the spiked Cd content rose from 10 to 120 mg kg‒1. The BCR SEP test revealed that the FNS addition substantially reduced the acid soluble fraction and increased the residual fraction of Cd, indicating the reduction of mobility and bioavailability of Cd in soils. The chemical precipitation, ion exchange and surface complexation might be involved in in situ immobilization of Cd-contaminated soils by the FNS.


Assuntos
Cádmio/análise , Poluição Ambiental/análise , Ferro/química , Níquel/química , Poluentes do Solo/análise , Solo/química , Disponibilidade Biológica , Cádmio/química , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química
19.
Clin Exp Med ; 19(4): 571-576, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31598794

RESUMO

Interleukin (IL)-8 has been reported to be associated with the progression of sepsis. Recent studies have explored the relationship between the IL-8 - 251 A/T polymorphism and sepsis risk. This study evaluated the association between the IL-8 - 251 A/T polymorphism and sepsis susceptibility in a Chinese Han population. We designed a case-control study with 254 sepsis cases and 322 controls. Genotyping was performed using the polymerase chain reaction-restriction fragment length polymorphism method. SPSS 20.0 software was used for all statistical analysis (SPSS Inc., Chicago, USA). This study showed that the IL-8 - 251 A/T polymorphism was associated with a decreased risk of sepsis. Stratified analyses found that this association held true in females, non-smokers, and older individuals (age > 60 years). The IL-8 - 251 A/T polymorphism was also related to the severity and 28-day mortality of sepsis. The IL-8 - 251 A/T polymorphism is associated with a decreased risk of sepsis.

20.
Remote Sens Environ ; 231: 111176, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31534277

RESUMO

Spectroscopy is becoming an increasingly powerful tool to alleviate the challenges of traditional measurements of key plant traits at the leaf, canopy, and ecosystem scales. Spectroscopic methods often rely on statistical approaches to reduce data redundancy and enhance useful prediction of physiological traits. Given the mechanistic uncertainty of spectroscopic techniques, genetic modification of plant biochemical pathways may affect reflectance spectra causing predictive models to lose power. The objectives of this research were to assess over two separate years, whether a predictive model can represent natural and imposed variation in leaf photosynthetic potential for different crop cultivars and genetically modified plants, to assess the interannual capabilities of a partial least square regression (PLSR) model, and to determine whether leaf N is a dominant driver of photosynthesis in PLSR models. In 2016, a PLSR analysis of reflectance spectra coupled with gas exchange data was used to build predictive models for photosynthetic parameters including maximum carboxylation rate of Rubisco (V c,max ), maximum electron transport rate (J max ) and percentage leaf nitrogen ([N]). The model was developed for wild type and genetically modified plants that represent a wide range of photosynthetic capacities. Results show that hyperspectral reflectance accurately predicted V c,max, J max and [N] for all plants measured in 2016. Applying these PLSR models to plants grown in 2017 resulted in a strong predictive ability relative to gas exchange measurements for V c,max, but not for J max, and not for genotypes unique to 2017. Building a new model including data collected in 2017 resulted in more robust predictions, with R2 increases of 17% for V c,max . and 13% J max . Plants generally have a positive correlation between leaf nitrogen and photosynthesis, however, tobacco with reduced Rubisco (SSuD) had significantly higher [N] despite much lower V c,max. The PLSR model was able to accurately predict both lower V c,max and higher leaf [N] for this genotype suggesting that the spectral based estimates of V c,max and leaf nitrogen [N] are independent. These results suggest that the PLSR model can be applied across years, but only to genotypes used to build the model and that the actual mechanism measured with the PLSR technique is not directly related to leaf [N]. The success of the leaf-scale analysis suggests that similar approaches may be successful at the canopy and ecosystem scales but to use these methods across years and between genotypes at any scale, application of accurately populated physical based models based on radiative transfer principles may be required.

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