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1.
Plant Phenomics ; 6: 0181, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726389

RESUMEN

Leaves, crucial for plant physiology, exhibit various morphological traits that meet diverse functional needs. Traditional leaf morphology quantification, largely 2-dimensional (2D), has not fully captured the 3-dimensional (3D) aspects of leaf function. Despite improvements in 3D data acquisition, accurately depicting leaf morphologies, particularly at the edges, is difficult. This study proposes a method for 3D leaf edge reconstruction, combining 2D image segmentation with curve-based 3D reconstruction. Utilizing deep-learning-based instance segmentation for 2D edge detection, structure from motion for estimation of camera positions and orientations, leaf correspondence identification for matching leaves among images, and curve-based 3D reconstruction for estimating 3D curve fragments, the method assembles 3D curve fragments into a leaf edge model through B-spline curve fitting. The method's performances were evaluated on both virtual and actual leaves, and the results indicated that small leaves and high camera noise pose greater challenges to reconstruction. We developed guidelines for setting a reliability threshold for curve fragments, considering factors occlusion, leaf size, the number of images, and camera error; the number of images had a lesser impact on this threshold compared to others. The method was effective for lobed leaves and leaves with fewer than 4 holes. However, challenges still existed when dealing with morphologies exhibiting highly local variations, such as serrations. This nondestructive approach to 3D leaf edge reconstruction marks an advancement in the quantitative analysis of plant morphology. It is a promising way to capture whole-plant architecture by combining 2D and 3D phenotyping approaches adapted to the target anatomical structures.

2.
Clin Exp Nephrol ; 27(5): 465-472, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36840900

RESUMEN

BACKGROUND: It remains unclear whether urinary albumin changes can predict subsequent kidney disease progression in people with diabetes. METHODS: This retrospective cohort study included 4570 Japanese adults with type 2 diabetes (T2D). The exposure was changes in urinary albumin-to-creatinine ratio (UACR) over 3 years, categorized into three categories: ≤ - 30%, minor change, or ≥ 30%. During the exposure period, eGFR decline was also examined and categorized into two categories: < 30% or ≥ 30% decline. The primary outcome was the composite of eGFR halving or initiation of kidney replacement therapy (KRT). The secondary outcome was the initiation of KRT. RESULTS: In the spline model, the hazard ratio for the primary outcome increased linearly on the log2 scale of UACR changes. When classified into six groups based on the categories of UACR changes and eGFR decline, people with a ≤ - 30% UACR change and < 30% eGFR decline had a 38% lower incidence of the outcome compared to those with a minor UACR change and < 30% eGFR decline. Meanwhile, the risk in those with a ≤ - 30% UACR change and ≥ 30% eGFR decline was 2.89 times. People with a ≥ 30% UACR change had the higher risk, regardless of whether a ≥ 30% eGFR decline occurred. Similar results were obtained in the secondary outcome. CONCLUSIONS: UACR changes can be a useful surrogate for kidney disease progression in people with T2D. However, when setting a decrease in UACR as the surrogate, it may be necessary to simultaneously evaluate kidney function decline.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedades Renales , Adulto , Humanos , Albúminas/metabolismo , Albuminuria/orina , Creatinina/orina , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Progresión de la Enfermedad , Tasa de Filtración Glomerular , Riñón , Estudios Retrospectivos
3.
Diabetes Care ; 46(1): 183-189, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36399781

RESUMEN

OBJECTIVE: To elucidate the association of glomerular filtration rate (GFR) at baseline with subsequent progression of albuminuria in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS: This was a single-center retrospective cohort study of 6,618 Japanese adults with type 2 diabetes and urinary albumin-to-creatinine ratio of <300 mg/g, comprising 2,459 women and 4,159 men with a mean (± SD) age of 60 ± 12 years. The exposure was baseline estimated GFR (eGFR) (mL/min/1.73 m2), treated as a categorical variable and classified into five categories: ≥90, 75-90, 60-75, 45-60, and <45, as well as a continuous variable. The outcome was progression of albuminuria category (i.e., from normoalbuminuria to micro- or macroalbuminuria or from micro- to macroalbuminuria). Hazard ratios (HRs) for the outcome were estimated using the multivariable Cox proportional hazards model. In the analysis treating baseline eGFR as a continuous variable, the multivariable-adjusted restricted cubic spline model was used. RESULTS: During the median follow-up period of 6.3 years, 1,190 individuals reached the outcome. When those with a baseline eGFR of 75-90 mL/min/1.73 m2 were considered the reference group, HRs (95% CIs) for the outcome in those with a baseline eGFR of ≥90, 60-75, 45-60, or <45 mL/min/1.73 m2 were 1.38 (1.14-1.66), 1.34 (1.14-1.58), 1.81 (1.50-2.20), or 2.37 (1.84-3.05), respectively. Furthermore, the inverse J-shaped curve was more clearly shown by the spline model. CONCLUSIONS: This study of Japanese adults with type 2 diabetes suggests that both high and low GFRs are implicated in the pathogenesis of albuminuria progression.


Asunto(s)
Diabetes Mellitus Tipo 2 , Masculino , Adulto , Humanos , Femenino , Persona de Mediana Edad , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/orina , Tasa de Filtración Glomerular , Albuminuria/etiología , Estudios Retrospectivos , Pruebas de Función Renal , Factores de Riesgo
4.
Breed Sci ; 72(1): 19-30, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36045892

RESUMEN

The morphological traits of plants contribute to many important functional features such as radiation interception, lodging tolerance, gas exchange efficiency, spatial competition between individuals and/or species, and disease resistance. Although the importance of plant phenotyping techniques is increasing with advances in molecular breeding strategies, there are barriers to its advancement, including the gap between measured data and phenotypic values, low quantitativity, and low throughput caused by the lack of models for representing morphological traits. In this review, we introduce morphological descriptors that can be used for phenotyping plant morphological traits. Geometric morphometric approaches pave the way to a general-purpose method applicable to single units. Hierarchical structures composed of an indefinite number of multiple elements, which is often observed in plants, can be quantified in terms of their multi-scale topological characteristics using topological data analysis. Theoretical morphological models capture specific anatomical structures, if recognized. These morphological descriptors provide us with the advantages of model-based plant phenotyping, including robust quantification of limited datasets. Moreover, we discuss the future possibilities that a system of model-based measurement and model refinement would solve the lack of morphological models and the difficulties in scaling out the phenotyping processes.

5.
Diabetologia ; 65(1): 234-245, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34739552

RESUMEN

AIM/HYPOTHESIS: It remains unclear whether people with diabetes exhibiting non-albuminuric kidney insufficiency have higher risk of kidney function decline and mortality compared with those exhibiting preserved kidney function without albuminuria. Furthermore, information regarding the incidence of albuminuria in people with this unique phenotype is sparse. Here, we aimed to elucidate the risk of the kidney outcomes and all-cause mortality in people with diabetes exhibiting non-albuminuric kidney insufficiency. METHODS: In this retrospective cohort study, 8320 Japanese adults with type 2 diabetes were classified into four groups based on the presence of albuminuria and kidney insufficiency at baseline, defined as urinary albumin/creatinine ratio of equal to or above 30 mg/g and eGFR of less than 60 ml min-1 1.73 m-2, respectively. The primary composite kidney endpoint was a 50% decrease in eGFR from baseline or the initiation of kidney replacement therapy. The annual percentage change in eGFR slope and progression of albuminuria category were evaluated as the secondary and tertiary kidney endpoints, respectively. All-cause death was also set as the endpoint. RESULTS: Compared with people exhibiting non-albuminuric preserved kidney function, those with non-albuminuric kidney insufficiency had the higher risk for the primary kidney endpoint (HR 4.1; 95% CI 2.5, 6.7; p < 0.001), steep percentage change in eGFR slope (-1.96%/year vs -1.36%/year, p < 0.001), incidence of albuminuria (HR 2.1; 1.7, 2.6; p < 0.001) and all-cause mortality (HR 1.5; 1.2, 2.0; p = 0.003). In the sensitivity analyses treating the incidence of albuminuria as a competing risk, people with non-albuminuric kidney insufficiency still had higher risk for the primary kidney endpoint and all-cause mortality than those with non-albuminuric preserved kidney function (subdistribution HR 2.8; 1.4, 5.6; p = 0.004; and 1.6; 1.1, 2.2; p = 0.014, respectively). CONCLUSIONS/INTERPRETATION: People with type 2 diabetes exhibiting non-albuminuric kidney insufficiency had poorer kidney outcomes and life prognosis than those exhibiting non-albuminuric preserved kidney function.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Insuficiencia Renal Crónica , Insuficiencia Renal , Albuminuria , Tasa de Filtración Glomerular , Humanos , Riñón , Insuficiencia Renal/complicaciones , Estudios Retrospectivos , Factores de Riesgo
6.
Diabetes Res Clin Pract ; 172: 108519, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33096189

RESUMEN

AIMS: To examine the association of dipstick hematuria with kidney function and albuminuria in patients with type 2 diabetes (T2D). METHODS: A total of 7,945 patients with T2D were studied. In the cross-sectional study, patients were classified into 6 groups based on the stage of albuminuria and estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73 m2 at baseline. In the longitudinal study where patients were classified by the presence of hematuria, the primary composite endpoint was a 30% decrease in eGFR from baseline or the initiation of kidney replacement therapy. Other outcomes included eGFR slope and stage progression of albuminuria. RESULTS: Cross-sectionally, hematuria was more prevalent in patients with more advanced stages of albuminuria and with lower eGFR, independently of each other. In the longitudinal study, patients with hematuria experienced 50% increased incidence of the primary endpoint (p < 0.001). The eGFR slope was steeper in patients with hematuria than in those without hematuria (p < 0.001). On the other hand, hematuria was unlikely to be associated with the progression of albuminuria. CONCLUSIONS: In patients with T2D, dipstick hematuria was associated with prevalent albuminuria and reduced eGFR, as well as faster decline in kidney function but not higher risk of development or progression of albuminuria.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Hematuria/etiología , Insuficiencia Renal Crónica/complicaciones , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad
7.
Microsc Microanal ; 23(3): 472-483, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28399948

RESUMEN

High-quality color output from digital photocopiers and laser printers is in strong demand, motivating attempts to achieve fine dot reproducibility and stability. The resolution of a digital photocopier depends on the charge density distribution on the organic photoconductor surface; however, directly measuring the charge density distribution is impossible. In this study, we propose a new electron optical instrument that can rapidly measure the electrostatic latent image on an organic photoconductor surface, which is a dielectric surface, as well as a novel method to quantitatively estimate the charge density distribution on a dielectric surface by combining experimental data obtained from the apparatus via a computer simulation. In the computer simulation, an improved three-dimensional boundary charge density method (BCM) is used for electric field analysis in the vicinity of the dielectric material with a charge density distribution. This method enables us to estimate the profile and quantity of the charge density distribution on a dielectric surface with a resolution of the order of microns. Furthermore, the surface potential on the dielectric surface can be immediately calculated using the obtained charge density. This method enables the relation between the charge pattern on the organic photoconductor surface and toner particle behavior to be studied; an understanding regarding the same may lead to the development of a new generation of higher resolution photocopiers.

8.
Ultramicroscopy ; 176: 86-92, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28341556

RESUMEN

Advanced techniques for overcoming problems encountered during in situ electron holography experiments in which a voltage is applied to an ionic conductor are reported. The three major problems encountered were 1) electric-field leakage from the specimen and its effect on phase images, 2) high electron conductivity of damage layers formed by the focused ion beam method, and 3) chemical reaction of the specimen with air. The first problem was overcome by comparing experimental phase distributions with simulated images in which three-dimensional leakage fields were taken into account, the second by removing the damage layers using a low-energy narrow Ar ion beam, and the third by developing an air-tight biasing specimen holder.

9.
Ultramicroscopy ; 178: 20-26, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27528443

RESUMEN

In situ electron holography is used to observe changes of electric-potential distributions in an amorphous lithium phosphorus oxynitride (LiPON) solid-state electrolyte when different voltages are applied. 2D phase images are simulated by integrating the 3D potential distribution along the electron trajectory through a thin Cu/LiPON/Cu region. Good agreement between experimental and simulated phase distributions is obtained when the influence of the external electric field is taken into account using the 3D boundary-charge method. Based on the precise potential changes, the lithium-ion and lithium-vacancy distributions inside the LiPON layer and electric double layers (EDLs) are inferred. The gradients of the phase drops at the interfaces in relation to EDL widths are discussed.

10.
Ultramicroscopy ; 173: 64-70, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27923137

RESUMEN

Advanced techniques for overcoming problems encountered during in situ electron holography experiments in which a voltage is applied to an ionic conductor are reported. The three major problems encountered were 1) electric-field leakage from the specimen and its effect on phase images, 2) high electron conductivity of damage layers formed by the focused ion beam method, and 3) chemical reaction of the specimen with air. The first problem was overcome by comparing experimental phase distributions with simulated images in which three-dimensional leakage fields were taken into account, the second by removing the damage layers using a low-energy narrow Ar ion beam, and the third by developing an air-tight biasing specimen holder.

11.
ACS Nano ; 9(3): 3206-14, 2015 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-25738973

RESUMEN

Manipulation of individual graphene sheets/films into specific architectures at macroscopic scales is crucially important for practical uses of graphene. We present herein a versatile and robust method based on annealing of solid carbon precursors on nickel templates and thermo-assisted removal of poly(methyl methacrylate) under low vacuum of ∼0.6 Pa for fabrication of macroscopic, freestanding, and tubular graphene (TG) architectures. Specifically, the TG architectures can be obtained as individual and woven tubes with a diameter of ∼50 µm, a wall thickness in the range of 2.1-2.9 nm, a density of ∼1.53 mg·cm(-3), a thermal stability up to 600 °C in air, an electrical conductivity of ∼1.48 × 10(6) S·m(-1), and field emission current densities on the order of 10(4) A·cm(-2) at low applied electrical fields of 0.6-0.7 V·µm(-1). These properties show great promise for applications in flexible and lightweight electronics, electron guns, or X-ray tube sources.

12.
J Electron Microsc (Tokyo) ; 59 Suppl 1: S89-94, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20551446

RESUMEN

A simple and quick method to measure the electric field distribution near a specimen using a conventional transmission electron microscope has been developed. The electric field distribution around a field emitter needle was measured to evaluate the performance of the method. It was found that this method allows us to measure the 2D distribution of electric field quantitatively with error of <10% with submicron spatial resolution. The dedicated aperture and software to construct an automated analysis system have been developed.

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