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1.
J Hazard Mater ; 472: 134382, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38703675

RESUMO

The photocatalytic efficiency for removing volatile organic compounds (VOCs) is significantly influenced by operational parameters like humidity and flow velocity, exhibiting notable and inconsistent fluctuations in both lab-scale and large-scale demonstrations. In this study, operando spectroscopy and isotope analysis were employed to investigate the correlation between humidity levels and degradation of gaseous acetaldehyde using TiO2 photocatalysts, aiming to demonstrate the scaling-up of photocatalytic air purifier. It was observed that rate constants for the mineralization of acetaldehyde rapidly decreased by 30% as relative humidity increased from 25% to 80% in the flow system (with an air velocity, v = 0.78 m/s). However, batch system showed smaller change with only a 10% reduction of the rate constant. Humidity fluctuations were more pronounced under high-speed conditions and were amplified in air purifier (v = 3.8 m/s). Time-resolved operando spectroscopy using an 13C isotope of acetaldehyde revealed that humidity's distinct role in dark adsorption and photocatalytic reactions. Water was found to inhibit the formation of crotonaldehyde during aldol condensation reaction in dark condition. Moreover, water suppressed photocatalytic mineralization by inhibiting acetate oxidation to formate. These findings provide valuable insights for improving realistic air purification processes, underscoring the importance of identifying key intermediates and controlling humidity to enhance the selectivity of gaseous pollutant oxidation reactions.

2.
Am J Public Health ; 114(7): 696-704, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38696736

RESUMO

Objectives. To evaluate changes in monthly buprenorphine dispensation associated with federal prescribing policies in Washington State from 2012 to 2022. Methods. We conducted an interrupted time series analysis comparing monthly buprenorphine prescriptions dispensed per 1000 population after the Comprehensive Addiction and Recovery Act (CARA), Substance Use-Disorder Prevention That Promotes Opioid Recovery and Treatment for Patients and Communities Act (SUPPORT), and new prescribing rules during the COVID-19 pandemic. Buprenorphine formulated for opioid use disorder was included from the Washington State Prescription Monitoring Program. A log-linear autoregressive model measured linear trend changes. Results. Physician prescribing increased by 1.63% (95% confidence interval [CI] = 1.41%, 1.85%) per month after CARA with sustained declines after SUPPORT. Nurse practitioner (NP) prescribing increased by 19.48% (95% CI = 18.8%, 20.16%) per month after CARA with physician assistants (PAs) showing similar trends. Following the implementation of SUPPORT, NP and PA trends continued to increase at a reduced growth rate of 3.96% (95% CI = 2.01%, 5.94%) and 1.87% (95% CI = 0.56%, 3.19%), respectively. No prescribers experienced increases during the COVID-19 pandemic. Conclusions. CARA nearly tripled the buprenorphine prescribing rate. The SUPPORT Act initiated sustained declines for physician prescribing, and the COVID-19 period reversed gains for PAs and NPs. The current opioid crisis requires expanded efforts in Washington State. (Am J Public Health. 2024;114(7):696-704. https://doi.org/10.2105/AJPH.2024.307649).


Assuntos
Buprenorfina , COVID-19 , Transtornos Relacionados ao Uso de Opioides , Padrões de Prática Médica , Buprenorfina/uso terapêutico , Humanos , Washington , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Padrões de Prática Médica/estatística & dados numéricos , COVID-19/epidemiologia , Tratamento de Substituição de Opiáceos/estatística & dados numéricos , Prescrições de Medicamentos/estatística & dados numéricos , Análise de Séries Temporais Interrompida , Antagonistas de Entorpecentes/uso terapêutico , Analgésicos Opioides/uso terapêutico
3.
Front Plant Sci ; 15: 1387954, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685962

RESUMO

Root architecture traits are belowground traits that harness moisture and nutrients from the soil and are equally important to above-ground traits in crop improvement. In soybean, the root length locus qRL16.1 was previously mapped on chromosome 16. The qRL16.1 has been characterized by transcriptome analysis of roots in near-isogenic lines (NILs), gene expression analysis in a pair of lines contrasting with alleles of qRL16.1, and differential gene expression analysis in germplasm accessions contrasting with root length. Two candidate genes, Glyma.16g108500 and Glyma.16g108700, have shown relatively higher expression in longer root accessions than in shorter rooting accessions. The C-terminal domain of Glyma.16g108500 and Glyma.16g108700 is similar to the conserved domain of C-terminally encoded peptides (CEPs) that regulate root length and nutrient response in Arabidopsis. Two polymorphisms upstream of Glyma.16g108500 showed a significant association with primary root length and total root length traits in a germplasm set. Synthetic peptide assay with predicted CEP variants of Glyma.16g108500 and Glyma.16g108700 demonstrated their positive effect on primary root length. The two genes are root-specific in the early stage of soybean growth and showed differential expression only in the primary root. These genes will be useful for improving soybean to develop a deep and robust root system to withstand low moisture and nutrient regimes.

4.
Behav Sci (Basel) ; 14(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38392474

RESUMO

In the post-COVID-19 era, the content of work and the necessary skills are rapidly changing due to the digital transformation of the way people work. Entrepreneurial adaptability and digital capability are the most necessary competencies for exploring opportunities and quickly turning them into a professional career amid a crisis. Financial literacy is also essential for expanding skills in economic and social life. The purpose of this study is to verify the influence of university students' financial literacy and digital capability on entrepreneurial intention and the mediating effect of entrepreneurship. To this end, a survey was conducted on university students in Busan and Gyeongnam, and a sample of 162 respondents was verified using SPSS 28.0. As a result of the study, it was found that financial literacy had a partially positive effect on entrepreneurship and entrepreneurial intention. Digital capability was found to have a positive effect on entrepreneurship and entrepreneurial intention. It was found that entrepreneurship had a partially positive effect on entrepreneurial intention. It was found that entrepreneurship had a partially positive mediating effect between financial literacy and entrepreneurial intention. It was found that entrepreneurship had a positive mediating effect between digital capability and entrepreneurial intention. As a result of this study, it was confirmed that financial literacy, digital capability, and entrepreneurship are very important competencies for university students to adapt to new trends and promote start-ups in a rapidly changing job environment after COVID-19, suggesting the need for further education.

5.
Biom J ; 66(2): e2300037, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368275

RESUMO

Conventional canonical correlation analysis (CCA) measures the association between two datasets and identifies relevant contributors. However, it encounters issues with execution and interpretation when the sample size is smaller than the number of variables or there are more than two datasets. Our motivating example is a stroke-related clinical study on pigs. The data are multimodal and consist of measurements taken at multiple time points and have many more variables than observations. This study aims to uncover important biomarkers and stroke recovery patterns based on physiological changes. To address the issues in the data, we develop two sparse CCA methods for multiple datasets. Various simulated examples are used to illustrate and contrast the performance of the proposed methods with that of the existing methods. In analyzing the pig stroke data, we apply the proposed sparse CCA methods along with dimension reduction techniques, interpret the recovery patterns, and identify influential variables in recovery.


Assuntos
Genômica , Acidente Vascular Cerebral , Animais , Suínos , Genômica/métodos , Análise de Correlação Canônica , Algoritmos
6.
J Marital Fam Ther ; 50(2): 290-306, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38124395

RESUMO

Studies investigating the potential structures underlying the connection between mindfulness and romantic relationship quality are not sufficient and require additional empirical findings. The current study aimed to examine a hypothesized model underlying the association between mindfulness and relationship quality, while investigating the roles of individuals' level of awareness and application of care in a romantic relationship among 199 adult participants in a southeastern region of the United States. Structural equation modeling (SEM) and path analysis were executed to examine the hypothesized structural model, testing a multi-step pathway as to how mindfulness influences relationship quality. The SEM and path analyses showed a good fit for the present study's hypothesized model, indicating that individuals' mindfulness had a direct influence on their self-awareness level. Individuals' self-awareness and application of care mediated the link between mindfulness and relationship quality. Implications for family life educators, dyadic couples researchers, and marriage and family practitioners are discussed.


Assuntos
Atenção Plena , Adulto , Humanos , Análise de Classes Latentes , Casamento
7.
J Appl Stat ; 50(3): 675-690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36819077

RESUMO

The current large amounts of data and advanced technologies have produced new types of complex data, such as histogram-valued data. The paper focuses on classification problems when predictors are observed as or aggregated into histograms. Because conventional classification methods take vectors as input, a natural approach converts histograms into vector-valued data using summary values, such as the mean or median. However, this approach forgoes the distributional information available in histograms. To address this issue, we propose a margin-based classifier called support histogram machine (SHM) for histogram-valued data. We adopt the support vector machine framework and the Wasserstein-Kantorovich metric to measure distances between histograms. The proposed optimization problem is solved by a dual approach. We then test the proposed SHM via simulated and real examples and demonstrate its superior performance to summary-value-based methods.

8.
J Appl Stat ; 49(15): 3889-3907, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324486

RESUMO

Many research proposals involve collecting multiple sources of information from a set of common samples, with the goal of performing an integrative analysis describing the associations between sources. We propose a method that characterizes the dominant modes of co-variation between the variables in two datasets while simultaneously performing variable selection. Our method relies on a sparse, low rank approximation of a matrix containing pairwise measures of association between the two sets of variables. We show that the proposed method shares a close connection with another group of methods for integrative data analysis - sparse canonical correlation analysis (CCA). Under some assumptions, the proposed method and sparse CCA aim to select the same subsets of variables. We show through simulation that the proposed method can achieve better variable selection accuracies than two state-of-the-art sparse CCA algorithms. Empirically, we demonstrate through the analysis of DNA methylation and gene expression data that the proposed method selects variables that have as high or higher canonical correlation than the variables selected by sparse CCA methods, which is a rather surprising finding given that objective function of the proposed method does not actually maximize the canonical correlation.

9.
J Neurosci Methods ; 364: 109374, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34600917

RESUMO

BACKGROUND: In the Gaussian graphical model framework, precision matrices reveal conditional dependence structure among random variables. In functional magnetic resonance imaging (fMRI) data, estimating such precision matrices of multi-subjects and aggregating them to a group-level is an essential step for constructing a group brain network. NEW METHOD: In this article, we considered joint estimation of multiple precision matrices with regularized aggregation. Also, in the construction of a group precision matrix, we integrated robust aggregation to the estimation. In the estimation of individual precision matrices, we took a regularization approach to induce sparsity, which made brain network estimation more realistic. RESULTS: We demonstrated the effectiveness of the proposed method through simulated examples, and analyses on real fMRI data acquired during eye movement tasks assessing cognitive control. For the fMRI data, the joint estimation of multiple precision matrices (JEMP) with regularized aggregation (RA) captured more robust associations between task-relevant neural regions of interest (ROIs), compared to the analyses using JEMP alone. The JEMP with RA also was sensitive to increased neural efficiency after task practice. COMPARISON WITH EXISTING METHOD(S): The simple average of individual precision matrices may be affected by outliers and provide inconsistent outcomes between subject-level and group-level networks. In contrast, the proposed method yielded a robust group graph that could identify and ease the effect of outliers. CONCLUSIONS: The proposed method identified regions of practice-induced attenuation associated with reduced cognitive demand after repeat task exposure. Through simulated and real data, we demonstrated that this method does not require any distribution assumption, can identify outliers, and provides robust, representative group brain networks. This method can be applied to datasets that have extensive variability and/or multiple outliers, including applications to specific, and general, cognitive processes, as well as for studies that may require longitudinal data, such as pharmaceutical trials.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos
10.
Biosensors (Basel) ; 11(5)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34065000

RESUMO

As diagnostic biosensors for analyzing fluids from the human body, the development of inorganic NPs is of increasing concern. For one, nanoceramic phosphors have been studied to meet the increasing requirements for biological, imaging, and diagnostic applications. In this study, Y2O3 NPs co-doped with trivalent rare earths (erbium and ytterbium) were obtained using a liquid phase-pulsed laser ablation (LP-PLA) method after getting high density Er, Yb:Y2O3 ceramic targets by Spark plasma sintering (SPS). Most NPs are under 50 nm in diameter and show high crystallinity of cubic Y2O3 structure, containing (222), (440), and (332) planes via HR-TEM. Excitation under a 980 nm laser to a nanoparticle solution showed 525 and 565 nm green, and 660 nm red emissions. The green emission intensity increased and decreased with increasing Yb3+ additive concentration, when the red spectrum continuously strengthened. Utilizing this study's outcome, we suggest developing technology to mark invisible biomolecules dissolved in a solvent using UC luminescence of Er3+, Yb3+ co-doped Y2O3 NPs by LP-PLA. The LP-PLA method has a potential ability for the fabrication of UC NPs for biosensors with uniform size distribution by laser parameters.


Assuntos
Técnicas Biossensoriais , Secreções Corporais/química , Érbio/química , Humanos , Luminescência , Poliésteres , Itérbio/química
11.
Polymers (Basel) ; 13(5)2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33799974

RESUMO

Skin aging is caused by exposure to various external factors. Ultraviolet B (UVB) irradiation induces oxidative stress, photoaging, and inflammation in skin cells. Pinus densiflora Sieb. et Zucc. (red pine) has various antimicrobial and antioxidant activities. However, the anti-inflammatory effects of red pine on skin have rarely been reported. The protective effects of malonic acid (MA) isolated from Pinus densiflora were investigated against UVB-induced damage in an immortalized human keratinocyte cell line (HaCaT). MA increased levels of the antioxidant enzymes superoxide dismutase 1 (SOD-1) and heme oxygenase 1 (HO-1) via activation of nuclear factor-erythroid 2-related factor-2 (Nrf2), resulting in a reduction in UVB-induced reactive oxygen species (ROS) levels. Additionally, the inhibition of ROS increased HaCaT cell survival rate. Thus, MA downregulated the expression of ROS-induced nuclear factor-κB, as well as inflammation-related cytokines (interleukin-6, cyclooxygenase-2, and tumor necrosis factor-α). Furthermore, MA significantly suppressed the mitogen-activated protein kinase/activator protein 1 signaling pathway and reduced the expression of matrix metalloproteinases (MMPs; MMP-1, MMP-3, and MMP-9). In contrast, MA treatment increased the expression of collagen synthesis regulatory genes (COL1A1 and COL3A1) via regulation of Smad2/3 signal induction through transforming growth factor-ß. In conclusion, MA protected against UVB-induced photoaging via suppression of skin inflammation and induction of collagen biosynthesis.

12.
J Phys Chem Lett ; 12(11): 2770-2779, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33709718

RESUMO

Nickel oxides (NiO) as hole transport layers (HTLs) in inverted-type perovskite solar cells (PSCs) have been widely studied mainly because of their high stability under illumination. Increases in the power conversion efficiency (PCE) with NiO HTLs have been presented in numerous reports, although the photoluminescence (PL) quenching behavior does not coincide with the PCE increase. The dynamics of the charge carrier transport between the NiO HTLs and the organic-inorganic halide perovskite absorbers is not clearly understood yet and quite unusual, in contrast to organic/polymerics HTLs. We deposited NiO HTLs with precisely controlled thicknesses by atomic layer deposition (ALD) and studied their photovoltaic performances and hole transfer characteristics. Ground state bleaching (GSB) recovery was observed by ultrafast transient absorption spectroscopy (TAS), which suggested that backward hole injection occurred between the perovskites and NiO HTLs, so that the uncommon PL behaviors can be clearly explained. Backward hole injection from the NiO HTL to the perovskite absorber originated from their similar valence band (VB) energy positions. The thickness increase of the NiO HTLs induced VB sharing, which caused a red-shift of the photoinduced hole absorption spectrum in near-infrared (NIR) femtosecond TAS and a decrease in the PL intensity. Our studies on inorganic metal oxide transport layers, NiO in this work, with a thickness dependence and the comparison with organic layers provide a better understanding of the interfacial carrier dynamics in PSCs.

13.
J Med Food ; 24(1): 50-58, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33449861

RESUMO

Korean red pine needle (RPN) exhibits various biological and pharmacological activities. Among the various compounds of RPN, we isolated dehydroabietic and 4-epi-trans-communic acid. At first, we confirmed that two compounds inhibited angiotensin converting enzyme (ACE) and induced p-Akt in human umbilical vein endothelial cells (HUVEC). RPN extract powder significantly reduced systolic blood pressure in spontaneous hypertensive rats (SHRs) through the reduced expression of ACE and angiotensin type I receptors in the lungs of SHRs. The Lineweaver-Burk plots suggested that the two compounds were noncompetitive inhibitors of ACE. Using docking analysis, we found that two compounds showed the best returned pose at ACE active sites, and formed hydrogen and hydrophobic bonds with ACE residues. These results demonstrate that RPNs may be a source of compounds effective for preventing hypertension and may be useful in the development of antihypertensive drugs.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Diterpenos/uso terapêutico , Hipertensão/tratamento farmacológico , Pinus/química , Preparações de Plantas/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Peptidil Dipeptidase A/genética , Compostos Fitoquímicos/farmacologia , Ratos , Ratos Endogâmicos SHR
14.
Neural Regen Res ; 16(5): 842-850, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33229718

RESUMO

Magnetic resonance imaging (MRI) is a clinically relevant, real-time imaging modality that is frequently utilized to assess stroke type and severity. However, specific MRI biomarkers that can be used to predict long-term functional recovery are still a critical need. Consequently, the present study sought to examine the prognostic value of commonly utilized MRI parameters to predict functional outcomes in a porcine model of ischemic stroke. Stroke was induced via permanent middle cerebral artery occlusion. At 24 hours post-stroke, MRI analysis revealed focal ischemic lesions, decreased diffusivity, hemispheric swelling, and white matter degradation. Functional deficits including behavioral abnormalities in open field and novel object exploration as well as spatiotemporal gait impairments were observed at 4 weeks post-stroke. Gaussian graphical models identified specific MRI outputs and functional recovery variables, including white matter integrity and gait performance, that exhibited strong conditional dependencies. Canonical correlation analysis revealed a prognostic relationship between lesion volume and white matter integrity and novel object exploration and gait performance. Consequently, these analyses may also have the potential of predicting patient recovery at chronic time points as pigs and humans share many anatomical similarities (e.g., white matter composition) that have proven to be critical in ischemic stroke pathophysiology. The study was approved by the University of Georgia (UGA) Institutional Animal Care and Use Committee (IACUC; Protocol Number: A2014-07-021-Y3-A11 and 2018-01-029-Y1-A5) on November 22, 2017.

15.
Materials (Basel) ; 13(13)2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32635456

RESUMO

As jointed plain concrete pavements (JPCP) age in South Korea, the cost of pavement maintenance is increasing annually. To extend the life of jointed concrete pavements through preventive maintenance, this study used 2017 pavement management system data to analyze the effects of traffic volume, alkali-silica reaction (ASR) grade, age, smoothness, and damaged area on the remodeling index (RMI-a measure of expressway pavement condition). In addition, this study evaluates the final RMI as well as the corresponding pavement condition and change in RMI value after conducting preventive maintenance in lieu of resurfacing or overlaying. The results demonstrated that the effect of ASR grade increased as the RMI forecast year increased and that change in surface distress (△SD) increased with age (most intensively when the pavement was 15-20 years of age). Moreover, change in international roughness index (△IRI) increased with age and traffic volume (similarly within 15-20 years of pavement age). Hence, preventive maintenance is a must for sections with high traffic volume and age even if the RMI is low. Finally, performing repairs through preventive maintenance decreases the number of expressway sections requiring resurfacing and overlaying, thus extending the life of the concrete pavement.

16.
Food Sci Biotechnol ; 29(6): 845-853, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32523794

RESUMO

Pinus densiflora sieb. et zucc.(pine needle) is a traditional medicine used in several East Asian countries. However, the efficacy of pine needle has rarely been reported. In this study showed that the anti-proliferative effects and the mechanisms of hexane layer of pine needle MeOH extract (PNH) on gastric cancer cells. At first, PNH inhibited the proliferation of gastric cancer cells in a dose-dependent manner. Moreover, PNH treatment induced G1 phase cell cycle arrest through the increased p27KIP1 expression and decreased cyclin dependent kinase (CDKs) activity. Furthermore, PNH treatment induced premature senescence without oncogenic stress, through the expression of p27KIP1 and Skp2. Taken together, these results showed that PNH inhibited gastric cancer cell proliferation through the induction of G1-cell cycle arrest and premature senescence via induced p27KIP1 expression, as controlled by Skp2 reduction. Also, PNH could be a candidate for anti-gastric cancer treatment and may be useful in the development of anti-gastric cancer drugs.

17.
Materials (Basel) ; 13(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906258

RESUMO

The compressive stress of concrete is used as a design variable for reinforced concrete structures in design standards. However, as the performance-based design is being used with increasing varieties and strengths of concrete and reinforcement bars, mechanical properties other than the compressive stress of concrete are sometimes used as major design variables. In particular, the evaluation of the mechanical properties of concrete is crucial when using fiber-reinforced concrete. Studies of high volume fractions in established compressive behavior prediction equations are insufficient compared to studies of conventional fiber-reinforced concrete. Furthermore, existing prediction equations for the mechanical properties of high-performance fiber-reinforced cementitious composite and high-strength concrete have limitations in terms of the strength and characteristics of contained fibers (diameter, length, volume fraction) even though the stress-strain relationship is determined by these factors. Therefore, this study developed a high-performance slurry-infiltrated fiber-reinforced cementitious composite that could prevent the fiber ball phenomenon, a disadvantage of conventional fiber-reinforced concrete, and maximize the fiber volume fraction. Then, the behavior characteristics under compressive stress were analyzed for fiber volume fractions of 4%, 5%, and 6%.

18.
J Appl Stat ; 47(6): 997-1016, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-35706918

RESUMO

This paper proposes a calibrated concave convex procedure (calibrated CCCP) for high-dimensional graphical model selection. The calibrated CCCP approach for the smoothly clipped absolute deviation (SCAD) penalty is known to be path-consistent with probability converging to one in linear regression models. We implement the calibrated CCCP method with the SCAD penalty for the graphical model selection. We use a quadratic objective function for undirected Gaussian graphical models and adopt the SCAD penalty for sparse estimation. For the tuning procedure, we propose to use columnwise tuning on the quadratic objective function adjusted for test data. In a simulation study, we compare the performance of the proposed method with two existing graphical model estimators for high-dimensional data in terms of matrix error norms and support recovery rate. We also compare the bias and the variance of the estimated matrices. Then, we apply the method to functional magnetic resonance imaging (fMRI) data of an attention deficit hyperactivity disorders (ADHD) patient.

19.
PLoS One ; 14(12): e0226116, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31805143

RESUMO

The timing of both flowering and maturation determine crop adaptability and productivity. Soybean (Glycine max) is cultivated across a wide range of latitudes. The molecular-genetic mechanisms for flowering in soybean have been determined for photoperiodic responses to long days (LDs), but remain only partially determined for the delay of flowering under short-day conditions, an adaptive trait of cultivars grown in lower latitudes. Here, we characterized the late-flowering (LF) habit introduced from the Thai cultivar K3 into a photoperiod-insensitive genetic background under different photo-thermal conditions, and we analyzed the genetic basis using quantitative trait locus (QTL) mapping. The LF habit resulted from a basic difference in the floral induction activity and from the suppression of flowering, which was caused by red light-enriched LD lengths and higher temperatures, during which FLOWERING LOCUS T (FT) orthologs, FT2a and FT5a, were strongly down-regulated. QTL mapping using gene-specific markers for flowering genes E2, FT2a and FT5a and 829 single nucleotide polymorphisms obtained from restriction-site associated DNA sequencing detected three QTLs controlling the LF habit. Of these, a QTL harboring FT2a exhibited large and stable effects under all the conditions tested. A resequencing analysis detected a nonsynonymous substitution in exon 4 of FT2a from K3, which converted the glycine conserved in FT-like proteins to the aspartic acid conserved in TERMINAL FLOWER 1-like proteins (floral repressors), suggesting a functional depression in the FT2a protein from K3. The effects of the remaining two QTLs, likely corresponding to E2 and FT5a, were environment dependent. Thus, the LF habit from K3 may be caused by the functional depression of FT2a and the down-regulation of two FT genes by red light-enriched LD conditions and high temperatures.


Assuntos
Mapeamento Cromossômico , Flores/crescimento & desenvolvimento , Glycine max/genética , Glycine max/efeitos da radiação , Fotoperíodo , Locos de Características Quantitativas/genética , Temperatura Alta , Luz , Desequilíbrio de Ligação , Proteínas de Plantas/genética , Polimorfismo Genético , Glycine max/crescimento & desenvolvimento
20.
BMC Plant Biol ; 19(1): 510, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752696

RESUMO

BACKGROUND: Soybean is one of the most important crop sources of tocopherols (Toc). However, the content of α-Toc, an isoform with the highest vitamin E activity in humans, is low in most cultivars. With the aim of broadening genetic variability, we performed quantitative trait locus (QTL) analysis for a high seed α-Toc trait detected in a wild soybean and characterized the sequence polymorphisms and expression profiles of γ-tocopherol methyltransferase (γ-TMT) genes as potential candidates. RESULTS: A recombinant inbred line population was developed from a cross between the low α-Toc breeding line TK780 and the high α-Toc wild accession B04009. The α-Toc content in seeds correlated strongly with the ratio of α-Toc to γ-Toc contents. QTL analysis using a high-density map constructed with 7710 single nucleotide polymorphisms (SNPs) generated by restriction site-associated DNA sequencing detected six QTLs involved in α-Toc biosynthesis. Of these, three in chromosomes (Chr) 9, 11, and 12 produced consistent effects during a 2-year trial. B04009 allele at QTLs in Chr9 and Chr12 and TK780 allele at the QTL in Chr11 each promoted the conversion of γ-Toc to α-Toc, which elevated the seed α-Toc content. SNPs and indels were detected between the parents in three γ-TMT genes (γ-TMT1, γ-TMT2, and γ-TMT3) co-located in the QTLs in Chr9 and Chr12, of which some existed in the cis-regulatory elements associated with seed development and functions. In immature cotyledons, γ-TMT3 was expressed at higher levels in B04009 than TK780, irrespective of two thermal conditions tested, whereas the expression of γ-TMT2 was markedly upregulated under higher temperatures, particularly in B04009. CONCLUSIONS: We identified QTLs consistently controlling α-Toc biosynthesis in wild soybean seeds in 2-year trials. The QTL on Chr9 had been previously identified in soybean, whereas the QTLs on Chr11 and Chr12 were novel. Further molecular dissections and characterization of the QTLs may facilitate the use of high α-Toc alleles from wild soybean in soybean breeding and an understanding of the molecular mechanisms underlying α-Toc biosynthesis in soybean seeds.


Assuntos
Glycine max/genética , Metiltransferases/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , alfa-Tocoferol/metabolismo , Alelos , Cruzamento , Alimento Funcional , Endogamia , Metiltransferases/genética , Fenótipo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/fisiologia , Análise de Sequência de DNA , Glycine max/fisiologia , Tocoferóis
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