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1.
Sensors (Basel) ; 23(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37420627

RESUMEN

The use of non-destructive commercial near-infrared (NIR) spectroscopy to estimate Brix% was verified using all samples of cherry tomato 'TY Chika', currant tomato 'Microbeads', and the M&S or market-purchased and supplemental local source tomatoes. Additionally, the relationship between fresh weight and Brix% of all samples was examined. These tomatoes had a diversity of cultivars, growing methods, harvest timing, and production locations and varied widely from 4.0% to 14.2% for Brix% and 1.25 g to 95.84 g for fresh weight. Regardless of the diversity of all samples, it was revealed that the refractometer-based Brix% (y) was practically estimated from the NIR-derived Brix% value (x) using a relationship of y = x (RMSE = 0.747 Brix%) after only a one-time calibration for the NIR spectrometer offset. An inverse relationship between fresh weight and Brix% could be modeled using a hyperbolic curve fit, and the model showed an R2 of 0.809 except for 'Microbeads'. The Brix% of 'TY Chika' was highest on average (9.5%) and had a large difference from 6.2 to 14.2% among the samples. Data distribution of cherry tomato groups such as 'TY Chika' and M&S cherry tomatoes was closer, indicating a roughly linear correlation between fresh weight and Brix%.


Asunto(s)
Solanum lycopersicum , Espectroscopía Infrarroja Corta , Frutas , Refractometría
2.
Cells ; 12(5)2023 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-36899877

RESUMEN

The developmental origins of health and disease (DOHaD) indicate that fetal tissues and organs in critical and sensitive periods of development are susceptible to structural and functional changes due to the adverse environment in utero. Maternal immune activation (MIA) is one of the phenomena in DOHaD. Exposure to maternal immune activation is a risk factor for neurodevelopmental disorders, psychosis, cardiovascular diseases, metabolic diseases, and human immune disorders. It has been associated with increased levels of proinflammatory cytokines transferred from mother to fetus in the prenatal period. Abnormal immunity induced by MIA includes immune overreaction or immune response failure in offspring. Immune overreaction is a hypersensitivity response of the immune system to pathogens or allergic factor. Immune response failure could not properly fight off various pathogens. The clinical features in offspring depend on the gestation period, inflammatory magnitude, inflammatory type of MIA in the prenatal period, and exposure to prenatal inflammatory stimulation, which might induce epigenetic modifications in the immune system. An analysis of epigenetic modifications caused by adverse intrauterine environments might allow clinicians to predict the onset of diseases and disorders before or after birth.


Asunto(s)
Efectos Tardíos de la Exposición Prenatal , Embarazo , Femenino , Humanos , Sistema Inmunológico/metabolismo , Parto , Citocinas , Madres
3.
J Inflamm Res ; 14: 355-365, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33603435

RESUMEN

BACKGROUND: A number of childhood diseases have been identified, such as severe infection or autoinflammatory disease, in which immune overreaction against inflammation is a possible underlying mechanism. Previous reports have demonstrated that fetal cells exposed to maternal immune activation (MIA) induced by polyriboinosinic-polyribocytidylic acid [poly(I:C)] exhibited hypersensitivity to inflammation in vitro. However, the details of this mechanism remain unclear. Therefore, this study aimed to reveal the reaction to inflammation in offspring exposed to MIA in the prenatal period, as well as its molecular mechanism, using a viral infection mouse model. MATERIALS AND METHODS: Pregnant mice at 12.5, 14.5, and 16.5 days post coitum were injected intraperitoneally with poly(I:C) 20 mg/kg body weight (BW) or saline. Offspring aged 3-4 weeks received the second injection of 20 mg/kg BW or 4 mg/kg BW poly(I:C) or saline. Serum and tissues were collected at 2, 24, 48, and 72 h after the postnatal injection. The cytokine profile, histopathology of organs, and unfolded protein response (UPR) in offspring were examined. RESULTS: The serum levels of interleukin (IL)-6, IL-17, and interferon-γ were significantly higher in the MIA group, and acute liver necrosis was detected. Moreover, failure in UPR was observed in the MIA group compared with that in the control group. CONCLUSION: Overall, MIA exposure in utero caused failure in UPR as well as immune overreaction to the second attack of inflammation in offspring. Our results suggested that prenatal exposure to MIA might contribute to the congenital inflammatory constitution after birth.

4.
Plant Methods ; 16: 118, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32874194

RESUMEN

BACKGROUND: Measurement of plant structure is useful in monitoring plant conditions and understanding the responses of plants to environmental changes. 3D imaging technologies, especially the passive-SfM (Structure from Motion) algorithm combined with a multi-camera photography (MCP) system has been studied to measure plant structure due to its low-cost, close-range, and rapid image capturing ability. However, reconstruction of 3D plant models with complex structure is a time-consuming process and some systems have failed to reconstruct 3D models properly. Therefore, an MCP based SfM system was developed and an appropriate reconstruction method and optimal range of camera-shooting angles were investigated. RESULTS: An MCP system which utilized 10 cameras and a rotary table for plant was developed. The 3D mesh model of a single leaf reconstruction using a set of images taken at each viewing zenith angle (VZA) from 12° (C2 camera) to 60° (C6 camera) by the MCP based SfM system had less undetected or unstable regions in comparison with other VZAs. The 3D mesh model of a whole plant, which merged 3D dense point cloud models built from a set of images taken at each appropriate VZA (Method 1), had high accuracy. The Method 1 error percentages for leaf area, leaf length, leaf width, stem height, and stem width are in the range of 2.6-4.4%, 0.2-2.2%, 1.0-4.9%, 1.9-2.8%, and 2.6-5.7% respectively. Also, the error of the leaf inclination angle was less than 5°. Conversely, the 3D mesh model of a whole plant built directly from a set of images taken at all appropriate VZAs (Method 2) had lower accuracy than that of Method 1. For Method 2, the error percentages of leaf area, leaf length, and leaf width are in the range of 3.1-13.3%, 0.4-3.3%, and 1.6-8.6%, respectively. It was difficult to obtain the error percentages of stem height and stem width because some information was missing in this model. In addition, the calculation time for Method 2 was 1.97 times longer computational time in comparison to Method 1. CONCLUSIONS: In this study, we determined the optimal shooting angles on the MCP based SfM system developed. We found that it is better in terms of computational time and accuracy to merge partial 3D models from images taken at each appropriate VZA, then construct complete 3D model (Method 1), rather than to construct 3D model by using images taken at all appropriate VZAs (Method 2). This is because utilization of incorporation of incomplete images to match feature points could result in reduced accuracy in 3D models and the increase in computational time for 3D model reconstruction.

6.
J Nanosci Nanotechnol ; 16(4): 3277-81, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27451617

RESUMEN

In this study, we used a liquid crystalline (LC) semiconductor, 8TNAT8, solution (e.g., 0.1 wt% in toluene) for forming an organic semiconductor layer by solution casting method, and fabricated bottom-gate/bottom-contact type field effect transistors (FETs). These LC semiconductors show FET characteristic properties and have high carrier mobility of 0.01 cm2 V-1 s-1. We have investigated the surface morphology and the influence of temperature variation on LC FET properties across the phase transition from crystal to mesophase of a LC semiconductor, 8TNAT8. In the most cases, FET mobility was irreversibly decreased after. temperature heat stress above the melting point of 8TNAT8, owing to the morphological change of LC layer.

7.
ChemistryOpen ; 5(2): 150-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27308226

RESUMEN

The spontaneous organization of two-dimensional polyaromatic molecules into well-defined nanostructures through noncovalent interactions is important in the development of organic-based electronic and optoelectronic devices. Two regioisomers of thiophene-fused zinc naphthalocyanines ZnTNcendo and ZnTNcexo have been designed and synthesized to obtain photo- and electroactive liquid crystalline materials. Both compounds exhibited liquid crystalline behavior over a wide temperature range through intermolecular π-π interactions and local phase segregation between the aromatic cores and peripheral side chains. The structural differences between ZnTNcendo and ZnTNcexo affected the stacking mode in self-assembled columns, as well as symmetry of the two-dimensional rectangular columnar lattice. The columnar structure in liquid crystalline phase exhibited an ambipolar charge-transport behavior.

8.
Sensors (Basel) ; 16(6)2016 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-27314348

RESUMEN

For plant breeding and growth monitoring, accurate measurements of plant structure parameters are very crucial. We have, therefore, developed a high efficiency Multi-Camera Photography (MCP) system combining Multi-View Stereovision (MVS) with the Structure from Motion (SfM) algorithm. In this paper, we measured six variables of nursery paprika plants and investigated the accuracy of 3D models reconstructed from photos taken by four lens types at four different positions. The results demonstrated that error between the estimated and measured values was small, and the root-mean-square errors (RMSE) for leaf width/length and stem height/diameter were 1.65 mm (R² = 0.98) and 0.57 mm (R² = 0.99), respectively. The accuracies of the 3D model reconstruction of leaf and stem by a 28-mm lens at the first and third camera positions were the highest, and the number of reconstructed fine-scale 3D model shape surfaces of leaf and stem is the most. The results confirmed the practicability of our new method for the reconstruction of fine-scale plant model and accurate estimation of the plant parameters. They also displayed that our system is a good system for capturing high-resolution 3D images of nursery plants with high efficiency.


Asunto(s)
Capsicum/anatomía & histología , Fotograbar/instrumentación , Hojas de la Planta/anatomía & histología , Tallos de la Planta/anatomía & histología
9.
Chemistry ; 21(29): 10379-90, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26095600

RESUMEN

Four new donor-acceptor triads (D-A-D) based on discotic and arylene mesogens have been synthesized by using Sonogashira coupling and cyclization reactions. This family of triads consists of two side-on pending triphenylene mesogens, acting as the electron-donating groups (D), laterally connected through short lipophilic spacers to a central perylenediimide (PI), benzo[ghi]perylenediimide (BI), or coronenediimide (CI) molecular unit, respectively, playing the role of the electron acceptor (A). All D-A-D triads self-organize to form a lamello-columnar oblique mesophase, with a highly segregated donor-acceptor (D-A) heterojunction organization, consequent to efficient molecular self-sorting. The structure consists in the regular alternation of two disrupted rows of triphenylene columns and a continuous row of diimine species. High-resolution STM images demonstrate that PI-TP2 forms stable 2D self-assembly nanostructures with some various degrees of regularity, whereas the other triads do not self-organize into ordered architectures. The electron-transport mobility of CI-TP2, measured by time-of-flight at 200 °C in the mesophase, is one order of magnitude higher than the hole mobility. By means of this specific molecular designing idea, we realized and demonstrated for the first time the so-called p-n heterojunction at the molecular level in which the electron-rich triphenylene columns act as the hole transient pathways, and the coronenediimide stacks form the electron-transport channels.

10.
ACS Appl Mater Interfaces ; 7(2): 1107-13, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25536370

RESUMEN

We reported before that a silica hollow particle whose shell consists of silica nanoparticle (SHP-NP) has a high light reflection ability to prevent light transmission through the particle, which is caused from the intensive light diffusion by the hollow structure and the nanoparticle of the shell. Since the difference in the refractive indices between silica and air is responsible for the strong light reflection, the mixing of the particle with organic components having refractive indices close to that of silica such as tetradecane produced transparent mixtures by suppression of the light reflection. The transparency of the mixtures thus prepared could be controlled by temperature variation. For example, the mixture of the particle SHP-NP with tetradecane was transparent at 20 °C and opaque at 70 °C, while the mixture with n-hexyl cyclohexane was opaque at 20 °C and transparent at 70 °C. As the refractive indices of organic components changed with temperature more than 10 times wider than that of silica, the temperature alternation produced a significant change in the difference of the refractive indices between them to achieve complete control of the transparency of the mixtures. This simple control of the light transmission that can automatically regulate sunlight into the room with temperature alteration is expected to be suitable for smart glass technology for energy conservation.

11.
Artículo en Inglés | MEDLINE | ID: mdl-25019803

RESUMEN

The structures of the discotic liquid crystalline (LC) phase of metal-free octa-substituted phthalocyanine (Pc) derivatives were investigated using molecular dynamics (MD) simulations. Special attention was paid to the LC phase structure of the non-peripheral octa-hexyl substituted Pc-derivatives that were recently found to show very high carrier mobilities for the discotic LCs. We obtained spontaneous transition to the columnar hexagonal (Col_{h}) LC phase in a melting simulation from the crystal structure obtained using an x-ray diffraction study. In this simulated Col_{h} structure, the Pc-core normal vectors were tilted 47{∘} from the column axis in parallel within each column, but the tilting directions are disordered between columns. We also found that the inter-core distance was not as large as previously suggested (0.4-0.5 nm) but similar to the common value (0.36 nm). This may resolve the contradiction between the high carrier mobility of the non-peripheral substituted Pcs, because larger inter-core separations degrade the mobilities.


Asunto(s)
Indoles/química , Cristales Líquidos/química , Congelación , Isoindoles , Simulación de Dinámica Molecular , Estructura Molecular , Difracción de Rayos X
12.
Chemistry ; 19(34): 11251-60, 2013 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-23821553

RESUMEN

We present herein the synthesis and properties of the largest hitherto unknown graphyne fragment, namely trigonally expanded tetrakis(dehydrobenzo[12]annulene)s (tetrakis-DBAs). Intramolecular three-fold alkyne metathesis reactions of hexakis(arylethynyl)DBAs 9 a and 9 b using Fürstner's Mo catalyst furnished tetrakis-DBAs 8 a and 8 b substituted with tert-butyl or branched alkyl ester groups in moderate and fair yields, respectively, demonstrating that the metathesis reaction of this protocol is a powerful tool for the construction of graphyne fragment backbones. For comparison, hexakis(arylethynyl)DBAs 9 c-g have also been prepared. The one-photon absorption spectrum of tetrakis-DBA 8 a bearing tert-butyl groups revealed a remarkable bathochromic shift of the absorption cut-off (λcutoff ) compared with those of previously reported graphyne fragments due to extended π-conjugation. Moreover, in the two-photon absorption spectrum, 8 a showed a large cross-section for a pure hydrocarbon because of the planar para-phenylene-ethynylene conjugation pathways. Hexakis(arylethynyl)-DBAs 9 c-e and 9 g and tetrakis-DBA 8 b bearing electron-withdrawing groups aggregated in chloroform solutions. Comparison between the free energies of 9 e and 8 b bearing the same substituents revealed the more favorable association of the latter due to stronger π-π interactions between the extended π-cores. Polarized optical microscopy observations, DSC, and XRD measurements showed that 8 b and 9 e with branched alkyl ester groups displayed columnar rectangular mesophases. By the time-resolved microwave conductivity method, the columnar rectangular phase of 8 b was shown to exhibit a moderate charge-carrier mobility of 0.12 cm(2) V(-1) s(-1) . These results indicate that large graphyne fragments can serve as good organic semiconductors.

13.
ACS Appl Mater Interfaces ; 4(4): 2212-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22448895

RESUMEN

Microwrinkle grooves serve as open microchannel capillaries, where the capillary action depends on the wettability of a liquid on the groove surface. Here, we report the photoinduced capillary action of a liquid in such microwrinkle grooves. The wettability is changed through the irradiation of a photoresponsive microwrinkle surface. By utilizing micropattern light-projection apparatus, we prepare liquid filaments that fill only the microgrooves prescribed by the patterned light, with micrometer-scale spatial resolution. This new technology enables the precise spatial control of liquids on a solid surface, and thus, is applicable in the fields of micropatterning and open-channel microfluidics.

14.
J Phys Chem B ; 116(8): 2339-46, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22352959

RESUMEN

The Larmor frequency and temperature dependence of the proton nuclear magnetic resonance (NMR) spin-lattice relaxation time was measured in the isotropic and columnar phases of both chain-end fluorinated triphenylene disk-like and fully hydrogenated molecules. In the columnar phase, the results are interpreted in terms of the collective motions, due to the deformations of the columns, and individual molecular translational self-diffusion displacements and rotations/reorientacions. In the isotropic phase, local molecular motions and order fluctuations as a pretransitional effect were considered. The activation energies of the molecular motions of the partially fluorinated molecule were found to be higher than those corresponding to the hydrocarbon homologue. Our findings show a clear difference in the relaxation dispersion between the two liquid crystals homologues. In particular it is observed that the columnar undulations have a much stronger contribution to the relaxation rate in the low frequency regime in the case of the fully hydrogenated triphenylene. The effect of fluorination of the pheripheral chain enhances the columnar mesophase's stability.


Asunto(s)
Crisenos/química , Simulación de Dinámica Molecular , Alquilación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Protones , Temperatura
15.
J Am Chem Soc ; 133(28): 10736-9, 2011 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-21699188

RESUMEN

Liquid crystalline donor (i.e., phthalocyanine) was covalently linked to acceptor (i.e, fullerene) to achieve efficient charge-transport properties in a liquid crystalline phase. The columnar structure exhibited highly efficient ambipolar charge-transport character, demonstrating the potential utility of the strategy in organic electronics.

16.
Chem Commun (Camb) ; 47(22): 6290-2, 2011 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-21505687

RESUMEN

A new truxene discotic liquid crystal possessing only three octyloxy chains (3C8OTRX) was studied on the mesomorphic and semiconducting properties to reveal that it exhibits a high drift mobility of positive carriers in the order of 10(-2) cm(2) V(-1) s(-1) in the hexagonal ordered columnar (Col(ho)) mesophase.

17.
Small ; 7(4): 506-13, 2011 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-21246715

RESUMEN

The ability to control metal patterns at the micro- and nanoscales, along with the development of a simple fabrication method, is important to many applications in the fields of materials science, biological sensing, electronics, and photonics. Herein, a simple approach to fabricating gold micropatterns with controlled roughness is reported. In this approach, gold is evaporated onto a striped liquid micropattern formed on self-organized microwrinkles. Gold nanoribbons with higher roughness form on the liquid part of the substrate because the deposited gold atoms can diffuse, grow, and aggregate at the liquid-air interface, whereas flat gold films form on the solid part. The rough gold nanoribbons formed on the liquid can then be peeled off through contact with water. The extinction spectrum of the rough gold nanoribbons suggests characteristic surface-plasmon absorption. This shows the possibility of using rough gold nanoribbons with controlled shape in plasmonic technology.


Asunto(s)
Oro/química , Líquidos Iónicos/química , Nanoestructuras/química , Nanotecnología/métodos
18.
Chem Commun (Camb) ; (12): 1452-4, 2008 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-18338053

RESUMEN

Four derivatives of hexakis(4-alkoxybenzoyloxy)triphenylene, for which peripheral phenylene groups are fluorinated at the inner and the outer positions were studied for their mesomorphic behaviour to reveal that the alteration of fluorinated positions in the phenyl rings leads to a drastic change of the mesomorphism involving the thermal stability.

19.
J Chem Phys ; 124(3): 034704, 2006 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-16438597

RESUMEN

We studied the mechanism of surface anchoring of rodlike molecules on substrates with the surfaces corrugated at molecular scale by molecular-dynamics simulation. We constructed a model for substrates that can have anisotoropic topographical patterns such as corrugation. The structural and thermodynamic properties of rodlike molecules on the corrugated surfaces, including the elastic and anchoring properties, were calculated and the influence of the surface structure on the anchoring was discussed. We found that the rodlike molecules are aligned along the grooves of the corrugated surfaces guided by the anisotropic molecular interaction between the molecules and the corrugated surface. The strength of anchoring was found to be increased when the period of corrugation is decreased at molecular level.

20.
Chem Commun (Camb) ; (37): 3874-6, 2006 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-17268655

RESUMEN

The valence state and the mesomorphic behaviour of a new cerium phthalocyanine double-decker complex bearing thioalkyl substituents are described and spectroscopic studies have revealed that the metal center in this lanthanide double-decker complex is tetravalent making the whole molecule neutral.

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