Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Theor Appl Genet ; 137(6): 127, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733416

RESUMEN

KEY MESSAGE: Quantitative trait locus analysis identified independent novel loci in cucumbers responsible for resistance to races 0 and 1 of the anthracnose fungal pathogen Colletotrichum orbiculare. Cucumbers have been reported to be vulnerable to Colletotrichum orbiculare, causing anthracnose disease with significant yield loss under favorable conditions. The deployment of a single recessive Cssgr gene in cucumber breeding for anthracnose resistance was effective until a recent report on high-virulent strains infecting cucumbers in Japan conquering the resistance. QTL mapping was conducted to identify the resistance loci in the cucumber accession Ban Kyuri (G100) against C. orbiculare strains 104-T and CcM-1 of pathogenic races 0 and 1, respectively. A single dominant locus An5 was detected in the disease resistance hotspot on chromosome 5 for resistance to 104-T. Resistance to CcM-1 was governed by three loci with additive effects located on chromosomes 2 (An2) and 1 (An1.1 and An1.2). Molecular markers were developed based on variant calling between the corresponding QTL regions in the de novo assembly of the G100 genome and the publicly available cucumber genomes. Multiple backcrossed populations were deployed to fine-map An5 locus and narrow the region to approximately 222 kbp. Accumulation of An2 and An1.1 alleles displayed an adequate resistance to CcM-1 strain. This study provides functional molecular markers for pyramiding resistance loci that confer sufficient resistance against anthracnose in cucumbers.


Asunto(s)
Mapeo Cromosómico , Colletotrichum , Cucumis sativus , Resistencia a la Enfermedad , Enfermedades de las Plantas , Sitios de Carácter Cuantitativo , Cucumis sativus/microbiología , Cucumis sativus/genética , Colletotrichum/patogenicidad , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Marcadores Genéticos , Fenotipo , Ligamiento Genético , Genes de Plantas , Fitomejoramiento
2.
J Clin Psychol ; 80(6): 1306-1322, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38408189

RESUMEN

BACKGROUND: Meaning in life is a benchmark indicator of flourishing that can likely mitigate the severity of depression symptoms among persons seeking mental healthcare. However, patients contending with serious mental health difficulties often experience a painful void or absence of ultimate meaning in their lives that might hinder recovery. This two-wave longitudinal study examined temporal associations between perceived presence of meaning in life, struggles with ultimate meaning, flourishing, and depression symptoms among adults in a spiritually integrated inpatient treatment program. METHODS: Of the 242 patients assessed at intake, 90% (N = 218; 40% Cisgender male; 57% Cisgender female; 3.0% nonbinary) completed validated measures of these meaning-related factors and mental health outcomes at discharge. RESULTS: Cross-sectional analyses revealed perceptions of meaning in life and ultimate meaning struggles were inversely linked with one another along with being associated with indices of positive and negative mental health in varying ways at the start and end of treatment. Drawing upon a two-wave cross-lagged panel design, longitudinal structural equation modeling analyses supported a Primary Meaning Model whereby having a subjective sense of meaning in life at intake was prospectively linked with lower levels of ultimate meaning struggles and greater flourishing at discharge. However, baseline levels of mental health outcomes were not predictive of the meaning-related factors in this sample. CONCLUSION: Findings highlight the utility of assessing patients' perceived meaning in life and ultimate meaning struggles in spiritually integrated programs and for clinicians to be prepared to possibly address these meaning-related concerns in the treatment process.


Asunto(s)
Pacientes Internos , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Estudios Longitudinales , Pacientes Internos/psicología , Estudios Transversales , Espiritualidad , Depresión/psicología
3.
Theor Appl Genet ; 136(6): 136, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37231314

RESUMEN

KEY MESSAGE: Japanese weedy melon exhibits unique sex expression with interactions between previously reported sex determination genes and two novel loci. Sex expression contributes to fruit quality and yield in the Cucurbitaceae. In melon, orchestrated regulation by sex determination genes explains the mechanism of sex expression, resulting in a great variety of sexual morphologies. In this study, we examined the Japanese weedy melon UT1, which does not follow the reported model of sex expression. We conducted QTL analysis using F2 plants for flower sex on the main stem and the lateral branch and mapped "occurrence of pistil-bearing flower on the main stem" locus on Chr. 3 (Opbf3.1) and "type of pistil-bearing flower" (female or bisexual) loci on Chr. 2 (tpbf2.1) and Chr. 8 (tpbf8.1). The Opbf3.1 included the known sex determination gene CmACS11. Sequence comparison of CmACS11 between parental lines revealed three nonsynonymous SNPs. A CAPS marker developed from one of the SNPs was closely linked to the occurrence of pistil-bearing flowers on the main stem in two F2 populations with different genetic backgrounds. The UT1 allele on Opbf3.1 was dominant in F1 lines from crosses between UT1 and diverse cultivars and breeding lines. This study suggests that Opbf3.1 and tpbf8.1 may promote the development of pistil and stamen primordia by inhibiting CmWIP1 and CmACS-7 functions, respectively, making the UT1 plants hermaphrodite. The results of this study provide new insights into the molecular mechanisms of sex determination in melons and considerations for the application of femaleness in melon breeding.


Asunto(s)
Cucurbitaceae , Cucurbitaceae/genética , Flores/genética , Fitomejoramiento
4.
Sci Rep ; 13(1): 6771, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37186239

RESUMEN

Sodium niobate (NaNbO3) is a potential material for lead-free dielectric ceramic capacitors for energy storage applications because of its antipolar ordering. In principle, a reversible phase transition between antiferroelectric (AFE) and ferroelectric (FE) phases can be induced by an application of electric field (E) and provides a large recoverable energy density. However, an irreversible phase transition from the AFE to the FE phase usually takes place and an AFE-derived polarization feature, a double polarization (P)-E hysteresis loop, does not appear. In this study, we investigate the impact of chemically induced hydrostatic pressure (pchem) on the phase stability and polarization characteristics of NaNbO3-based ceramics. We reveal that the cell volume of Ca-modified NaNbO3 [(CaxNa1-2xVx)NbO3], where V is A-site vacancy, decreases with increasing x by a positive pchem. Structural analysis using micro-X-ray diffraction measurements shows that a reversible AFE-FE phase transition leads to a double P-E hysteresis loop for the sample with x = 0.10. DFT calculations support that a positive pchem stabilizes the AFE phase even after the electrical poling and provides the reversible phase transition. Our study demonstrates that an application of positive pchem is effective in delivering the double P-E loop in the NaNbO3 system for energy storage applications.

5.
Nanomaterials (Basel) ; 12(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36500793

RESUMEN

We investigate the origin of ferroelectricity in the BiFeO3-LaFeO3 system in rhombohedral R3c and tetragonal P4mm symmetries by ab initio density functional theory calculations and compare their electronic features with paraelectric orthorhombic Pnma symmetry. We show that a coherent accommodation of stereo-active lone pair electrons of Bi is the detrimental factor of ferroelectricity. A Bloch function arising from an indirect Bi_6p-Fe_3d hybridization mediated through O_2p is the primary origin of spontaneous polarization (Ps) in the rhombohedral system. In the orthorhombic system, a similar Bloch function was found, whereas a staggered accommodation of stereo-active lone pair electrons of Bi exclusively results in paraelectricity. A giant Ps reported in the tetragonal system originates from an orbital hybridization of Bi_6p and O_2p, where Fe-3d plays a minor role. The Ps in the rhombohedral system decreases with increasing La content, while that in the tetragonal system displays a discontinuous drop at a certain La content. We discuss the electronic factors affecting the Ps evolutions with La content.

6.
Breed Sci ; 72(4): 306-315, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36699825

RESUMEN

The pathogen Colletotrichum orbiculare is causal fungus of cucurbit anthracnose. Multiple races have been identified in the United States, suggesting that it is necessary to cultivate suitable resistant cultivars and breed new cultivars with the most suitable resistance gene. This study examined the pathogenicity and virulence of 20 strains in Japan to clarify the existence of races and virulence differences. Based on the symptoms on inoculated cotyledons and true leaves of watermelon, we could evaluate the compatibility of each strain to each host cultivar. Our analysis based on the reaction to the host cultivar harboring the resistance gene Ar-1 (Cla001017) revealed the existence of three races in Japan. An alarming result was that a race that overcame Ar-1, which is a target gene in current watermelon breeding in Japan, is present in Japan. The cucumber and melon host cultivars showed diverse symptoms, whereas a squash cultivar was resistant to all strains. Three strains caused severe damage even to the most resistant cucumber cultivar 'Ban Kyuri' and resistant cultivars harboring Cssgr, a well-known gene conferring loss-of-susceptibility resistance. Screening genetic resources for novel resistance genes using strains with high virulence is of vital importance for watermelon, cucumber, and melon production.

7.
Nanomaterials (Basel) ; 11(7)2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34361243

RESUMEN

Superlattice-structured epitaxial thin films composed of Mn(5%)-doped BiFeO3 and BaTiO3 with a total thickness of 600 perovskite (ABO3) unit cells were grown on single-crystal SrTiO3 substrates by pulsed laser deposition, and their polarization and dielectric properties were investigated. When the layers of Mn-BiFeO3 and BaTiO3 have over 25 ABO3 unit cells (N), the superlattice can be regarded as a simple series connection of their individual capacitors. The superlattices with an N of 5 or less behave as a unified ferroelectric, where the BaTiO3 and Mn-BiFeO3 layers are structurally and electronically coupled. Density functional theory calculations can explain the behavior of spontaneous polarization for the superlattices in this thin regime. We propose that a superlattice formation comprising two types of perovskite layers with different crystal symmetries opens a path to novel ferroelectrics that cannot be obtained in a solid solution system.

8.
RSC Adv ; 11(29): 17891-17900, 2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35480192

RESUMEN

The mechanism of electrochemical promotion of ammonia formation was investigated by kinetic and deuterium isotope analyses using a cell with a Pt (anode)|BaCe0.9Y0.1O3 (BCY)|Fe (cathode) configuration on the introduction of a gaseous mixture of H2(D2)-N2 to the cathode at 550 °C. To clarify the mechanism of electrochemical ammonia synthesis, the reaction orders for hydrogen, α, and nitrogen, ß, were investigated. The values of α and ß did not change after applying a negative voltage, which indicates that the reaction mechanism at rest potential is the same as that with cathodic polarization. Furthermore, deuterium isotope analysis was conducted to investigate the mechanism of electrochemical promotion. The isotopic composition of ammonia (i.e., NH3-x D x ) formed in the cathode was determined using Fourier-transform infrared spectroscopy (FTIR). The results show that the ammonia products with cathodic polarization correspond to the species of H2 (or D2) in the cathode, that is, NH3 (or ND3) was mainly formed when H2 (or D2) was introduced to the cathode. Isotopic analysis revealed that the ammonia formation rate via the electrochemical promotion of catalysis (EPOC) is faster than that via the charge-transfer reaction, suggesting that a significant increase in the ammonia formation rate will be caused by the EPOC.

9.
Sci Rep ; 9(1): 4225, 2019 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-30862877

RESUMEN

Controlling and manipulating defects in materials provides an extra degree of freedom not only for enhancing physical properties but also for introducing additional functionalities. In ferroelectric oxides, an accumulation of point defects at specific boundaries often deteriorates a polarization-switching capability, but on the one hand, delivers interface-driven phenomena. At present, it remains challenging to control oxygen vacancies at will to achieve a desirable defect structure. Here, we report a practical route to designing oxygen-vacancy distributions by exploiting the interaction with transition-metal dopants. Our thin-film experiments combined with ab-initio theoretical calculations for BiFeO3 demonstrate that isovalent dopants such as Mn3+ with a partly or fully electron-occupied eg state can trap oxygen vacancies, leading to a robust polarization switching. Our approach to controlling oxygen vacancy distributions by harnessing the vacancy-trapping capability of isovalent transition-metal cations will realize the full potential of switchable polarization in ferroelectric perovskite oxides.

10.
Nat Commun ; 8(1): 207, 2017 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-28785049

RESUMEN

Photoferroelectrics offer unique opportunities to explore light energy conversion based on their polarization-driven carrier separation and above-bandgap voltages. The problem associated with the wide bandgap of ferroelectric oxides, i.e., the vanishingly small photoresponse under visible light, has been overcome partly by bandgap tuning, but the narrowing of the bandgap is, in principle, accompanied by a substantial loss of ferroelectric polarization. In this article, we report an approach, 'gap-state' engineering, to produce photoferroelectrics, in which defect states within the bandgap act as a scaffold for photogeneration. Our first-principles calculations and single-domain thin-film experiments of BiFeO3 demonstrate that gap states half-filled with electrons can enhance not only photocurrents but also photovoltages over a broad photon-energy range that is different from intermediate bands in present semiconductor-based solar cells. Our approach opens a promising route to the material design of visible-light-active ferroelectrics without sacrificing spontaneous polarization.Overcoming the optical transparency of wide bandgap of ferroelectric oxides by narrowing its bandgap tends to result in a loss of polarization. By utilizing defect states within the bandgap, Matsuo et al. report visible-light-active ferroelectrics without sacrificing polarization.

11.
Artículo en Inglés | MEDLINE | ID: mdl-21096215

RESUMEN

The purpose of this study is to investigate transient process of the charring at the laser catheter-tip in blood during therapeutic laser irradiation by the back scattering light measurement to detect precursor state of the charring. We took account of using photodynamic therapy for arrhythmia in blood through the laser catheter. We observed the influence of the red laser irradiation (λ=663 nm) upon the shape of red blood cells (RBCs). The RBCs aggregation, round formation, and hemolysis were took place sequentially before charring. With a model blood sandwiched between glass plates simulated as a catheter-tip boundary, we measured diffuse-reflected-light power and transmitted-light power simultaneously and continuously by a microscopic optics during the laser irradiation. We found that measured light power changes were originated with RBCs shape change induced by temperature rise due to the laser irradiation. A gentle peak following a slow descending was observed in the diffuse-reflected-light power history. This history might indicate the precursor state of the charring, in which the hemolysis might be considered to advance rapidly. We think that the measurement of diffuse-reflected-light power history might be able to detect precursor state of charring at the catheter-tip in blood.


Asunto(s)
Catéteres , Rayos Láser , Fotoquimioterapia/instrumentación , Albúminas/metabolismo , Animales , Eritrocitos/citología , Eritrocitos/efectos de la radiación , Glucosa/química , Glucosa/metabolismo , Hemólisis , Luz , Óptica y Fotónica , Fotoquimioterapia/métodos , Conejos , Sales (Química)/química , Dispersión de Radiación , Temperatura , Factores de Tiempo
12.
Res Microbiol ; 159(9-10): 685-91, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18790050

RESUMEN

Lactobacillus plantarum LA 318 is a potential probiotic strain isolated from normal human intestinal tissue that shows high adhesion to human colonic mucin mediated by the bacterial cell surface glyceraldehyde-3-phosphate dehydrogenase (GAPDH). We report the adhesion mechanism of the lactobacilli is in part due to GAPDH binding to human ABO-type blood group antigens expressed on human colonic mucin (HCM). After periodate oxidation of HCM, adhesion of L. plantarum LA 318 bacterial cells significantly decreased compared to normal HCM. A BIACORE binding assay of GAPDH to blood group antigens was then performed. High binding was observed to A and B group antigens, while binding to H group antigen was lower (P<0.01). No interaction was observed between GAPDH and various monosaccharides. Furthermore, GAPDH binding to the B-trisaccharide biotinyl polymer (BP)-probe [Galalpha1-3 (Fucalpha1-2) Gal-] was significantly higher as compared to B-disaccharide, Lewis D-trisaccharide, 3-fucosyl-N-acetylglucosamine and alpha-N-acetylneuraminic acid BP-probes. The data suggests the trisaccharide structure is important in binding to the blood group antigens. The binding of GAPDH to HCM significantly decreased after incubation with NAD+. This suggests that the NAD binding domain on GAPDH may be related to binding to HCM.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/metabolismo , Colon/microbiología , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Lactobacillus plantarum/enzimología , Lactobacillus plantarum/fisiología , Mucinas/metabolismo , Sistema del Grupo Sanguíneo ABO/química , Adhesión Bacteriana , Colon/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Lactobacillus plantarum/aislamiento & purificación , Probióticos/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...