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1.
Small ; 19(8): e2204620, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36456203

RESUMEN

Protein assemblies have drawn much attention as platforms for biomedical applications, including gene/drug delivery and vaccine, due to biocompatibility and functional diversity. Here, the construction and functionalization of a protein assembly composed of human clathrin heavy chain and light chain for a targeted protein delivery, is presented. The clathrin heavy and light chains are redesigned and associated with each other, and the resulting triskelion unit further self-assembled into a clathrin assembly with the size of about 28 nm in diameter. The clathrin assembly is dual-functionalized with a protein cargo and a targeting moiety using two different orthogonal protein-ligand pairs through one-pot reaction. The functionalized clathrin assembly exhibits about a 900-fold decreased KD value for a cell-surface target due to avidity compared to a native targeting moiety. The utility of the clathrin assembly is demonstrated by an efficient delivery of a protein cargo into tumor cells in a target-specific manner, resulting in a strong cytotoxic effect. The present approach can be used in the creation of protein assemblies with multimodality.


Asunto(s)
Clatrina , Sistemas de Liberación de Medicamentos , Humanos , Clatrina/metabolismo
2.
J Aquat Anim Health ; 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38050651

RESUMEN

Feed additives have attracted increased attention in aquaculture due to their ability to modulate fish gut microbiota, resulting in improved fish growth and immunity. This study assessed two synbiotics' effects in Japanese eels: Bacillus subtilis with mannooligosaccharide (MOS) and Enterococcus faecium with fructooligosaccharide (FOS). Six diets, including a control (CON), oxytetracycline (OTC), and four synbiotic diets - B.subtilis at 1 × 106 and 107 CFU/g with 5 g/kg MOS (BS6MO and BS7MO) and E. faecium at 1 × 106 and 107 CFU/g with 5 g/kg FOS (EF6FO and EF7FO) - were fed to triplicate groups of 20 fish averaging 6.00 ± 0.07g for eight weeks. Fish fed the BSMOS diets showed significantly higher weight gain (WG), specific growth rate (SGR), and feed efficiency (FE) compared to the CON and OTC diets (P < 0.05), but not significantly different from those fed the EFFOS diets. Weight gain, SGR of fish fed EFFOS were not significantly different from those fed all other diets (P > 0.05). Fish fed the OTC diet showed a higher mean aspartate aminotransferase (AST) level, though the difference was not statistically significant. The myeloperoxidase (MPO) activity of fish fed the BS7MO diet was significantly higher than in all other diets, and the superoxide dismutase (SOD) activity of fish fed the BS7MO diet was also significantly higher than in the EF7FO diet. Overall, the BSMOS synbiotic diets were significantly more effective than the CON diet in enhancing fish survival against Vibrio anguillarum. Our findings suggest that synbiotics can be a preferable alternative to antibiotics in aquaculture.

3.
Nanotechnology ; 29(45): 455201, 2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30156565

RESUMEN

With the view towards future non-volatile random access memories that can be integrated at a large scale, extensive study on resistive switching (RS) devices arranged in a crossbar array is currently underway. Although the crossbar array architecture offers relatively simple and acceptable scalability, the presence of sneak current is recognized as a critical issue that needs to be resolved at device level. In addressing this issue, we demonstrate a new type of RS device fabricated by combining graphene oxide (G-O) and zinc oxide (ZnO) with highly asymmetric current-voltage (I-V) characteristics depending on the polarity of bias voltage. The distinctive highly asymmetric I-V characteristics result from the presence of a hetero-junction interface formed between the G-O and ZnO layers. This hetero-junction manifests resistance in the range of GΩ under both forward and reverse bias voltage when the device is in the OFF state, in contrast, when the device is in the ON state, it exhibits resistance in the range of MΩ or kΩ under forward bias and GΩ under reverse bias. We propose to employ demonstrated RS devices with highly asymmetric I-V characteristics to mitigate adverse effects of the sneak current.

4.
Nanotechnology ; 28(17): 175402, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28278133

RESUMEN

Recently, many researchers have been paying attention to nanogenerators (NGs) as energy sources for self-powered mirco-nano systems, and studying how to achieve their higher power generation. Hence, we propose a hybrid-type NG for harvesting both the piezoelectric and triboelectric effect simultaneously. In the proposed hybrid NG, the piezoelectric NG (PNG) and triboelectric NG (TENG) are fabricated using polydimethylsiloxane (PDMS) and perovskite zinc stannite (ZnSnO3) nanocubes with a high charge polarization of 59 uC cm-2 composite (PDMS + ZnSnO3) and UV surface-treated PDMS, respectively. To effectively combine a high output current of PNG and a high voltage of TENG, these two NGs are stacked upon each other, and separated by sponge spacers providing a uniform air gap for the triboelectric effect. In particular, this fabricated structure has a low Young's modulus for piezoelectricity. The proposed hybrid NG device effectively achieves a combined peak voltage of 300 V on an open circuit, a power density of 10.41 mW cm-2 at 1 MΩ load, and a maximum short circuit current density of 16 mA cm-2 at 50 Ω load. It is feasible that the proposed NG can be utilized as a source for various self-powered systems.

5.
Sensors (Basel) ; 17(12)2017 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-29258273

RESUMEN

In this paper, a compact microstrip feed inset patch sensor is proposed for measuring the salinities in seawater. The working principle of the proposed sensor depends on the fact that different salinities in liquid have different relative permittivities and cause different resonance frequencies. The proposed sensor can obtain better sensitivity to salinity changes than common sensors using conductivity change, since the relative permittivity change to salinity is 2.5 times more sensitive than the conductivity change. The patch and ground plane of the proposed sensor are fabricated by conductive copper spray coating on the masks made by 3D printer. The fabricated patch and the ground plane are bonded to a commercial silicon substrate and then attached to 5 mm-high chamber made by 3D printer so that it contains only 1 mL seawater. For easy fabrication and testing, the maximum resonance frequency was selected under 3 GHz and to cover salinities in real seawater, it was assumed that the salinity changes from 20 to 35 ppt. The sensor was designed by the finite element method-based ANSYS high-frequency structure simulator (HFSS), and it can detect the salinity with 0.01 ppt resolution. The designed sensor has a resonance frequency separation of 37.9 kHz and reflection coefficients under -20 dB at the resonant frequencies. The fabricated sensor showed better performance with average frequency separation of 48 kHz and maximum reflection coefficient of -35 dB. By comparing with the existing sensors, the proposed compact and low-cost sensor showed a better detection capability. Therefore, the proposed patch sensor can be utilized in radio frequency (RF) tunable sensors for salinity determination.

6.
Langmuir ; 32(44): 11432-11439, 2016 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-27718582

RESUMEN

Because printed resistance temperature detectors (RTDs) are affected by tension and compression of metallic patterns on flexible or curved surfaces, a significant temperature-sensing error occurs in general. Hence, we propose a differential temperature sensor (DTS) to compensate the bending effect of the printed RTDs, which is composed of two serially connected similar meander patterns fabricated back-to-back on a polyimide polyethylene terephthalate substrate through a Dimatix DMP-3000 inkjet printer using silver nanoparticles. Under mechanical deformation, the resistance of the proposed DTS is not varied significantly under the same temperature environment because its patterns vary differentially as one side experiences tension while the opposite side experiences compression. A single meander pattern of the proposed DTS has a total length of 75 mm and device dimensions of 7 × 7 mm2. The total resistance variation is observed to be 15.5 Ω against the temperature variation from 0 to 100 °C, and the temperature coefficient of resistance is 1.076 × 10-3 °C-1. The proposed DTS exhibits no significant resistance change on bendability testing down to 2 mm diameter because of mechanical deformation. In addition, it is also used to detect the curvature of a body shape down to 2 mm diameter because its resistance changes by ±8.22% using a single meander pattern of DTS. The proposed sensor can be applied on a curved or flexible surface to measure relatively accurate temperature when compared to a single meander pattern.

7.
Opt Express ; 23(24): 30583-91, 2015 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-26698691

RESUMEN

To apply in wearable electronics, we propose a stretchable photo sensor that detects an inversely changed resistance by varying light intensity, which is stably operated up to 25% axial strain. Especially, the stretchabity of the proposed photo sensor is achived by using a uniform ridged substrate made of polydimethylsiloxane (PDMS). The proposed device is composed of a thin film of perylene/graphene composite, which is sandwiched between bottom and top indium tin oxide (ITO) transparent electrodes fabricated through electro-hydrodynamic (EHD) technique. The electrical conductivity of perylene is improved by blending graphene with it. The resistance of the proposed photo sensor changes from 108 MΩ to 87 MΩ within the light intensity range of 0 to 400 lux, respectively. Furthermore, the flexibility is verified through a bendability test from 16 mm down to 0 mm and a bending endurance test for more than 1000 cycles. Uniform and smooth deposition of the active layer is tested through surface morphology characterization.


Asunto(s)
Conductometría/instrumentación , Dimetilpolisiloxanos/química , Grafito/química , Dispositivos Ópticos , Perileno/química , Fotometría/instrumentación , Módulo de Elasticidad , Electrodos , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Ensayo de Materiales
8.
Sensors (Basel) ; 14(9): 17807-16, 2014 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-25254305

RESUMEN

The mechanical scanning of a single element transducer has been mostly utilized for high-frequency ultrasound imaging. However, it requires space for the mechanical motion of the transducer. In this paper, a rotational scanning ultrasound biomicroscopy (UBM) system equipped with a high-frequency angled needle transducer is designed and implemented in order to minimize the space required. It was applied to ex vivo ultrasound imaging of porcine posterior ocular tissues through a minimal incision hole of 1 mm in diameter. The retina and sclera for the one eye were visualized in the relative rotating angle range of 270°~330° and at a distance range of 6~7 mm, whereas the tissues of the other eye were observed in relative angle range of 160°~220° and at a distance range of 7.5~9 mm. The layer between retina and sclera seemed to be bent because the distance between the transducer tip and the layer was varied while the transducer was rotated. Certin features of the rotation system such as the optimal scanning angle, step angle and data length need to be improved for ensure higher accuracy and precision. Moreover, the focal length should be considered for the image quality. This implementation represents the first report of a rotational scanning UBM system.


Asunto(s)
Diagnóstico por Imagen/métodos , Microscopía Acústica/métodos , Retina/diagnóstico por imagen , Esclerótica/diagnóstico por imagen , Animales , Ondas de Choque de Alta Energía , Retina/fisiología , Esclerótica/fisiología , Porcinos
9.
ACS Appl Mater Interfaces ; 16(36): 47100-47109, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39216082

RESUMEN

Specific targeting of tumor cells is a key to achieving high therapeutic efficacy while minimizing off-target side effects. As a general approach to targeting diverse tumor cells, considerable attention has been paid to the tumor microenvironment, particularly its slightly acidic pH (6.5-6.8). However, existing pH-sensitive nanomaterials, based on organic polymers and proteins, often lack sufficient pH sensitivity and specificity. Here, we demonstrate a strategy to construct a pH-responsive protein assembly through clustering of a single amino acid repeat as a charge-tunable moiety. As a proof of concept, a histidine peptide with varying lengths was displayed on the surface of a ferritin assembly composed of 24 subunits by genetic fusion to a subunit. The resulting self-assembled ferritin particles, termed "pHerricle (pH-responsive ferritin particle)", were shown to exhibit a specific binding to tumor cells in response to pH changes through cooperative effects of histidine peptides. Increasing the histidine peptide length from 0 to 12 residues increased the pHerricle's cell-binding capacity by 21-fold and allowed modulation of the targetable pH range. General applicability as a tumor cell-targeting platform was shown by specific delivery of a cytotoxic cargo by the pHerricle into tumor cells of various origins in a pH-dependent manner.


Asunto(s)
Ferritinas , Histidina , Concentración de Iones de Hidrógeno , Humanos , Histidina/química , Ferritinas/química , Ferritinas/metabolismo , Ferritinas/genética , Péptidos/química , Línea Celular Tumoral
10.
Adv Healthc Mater ; 13(4): e2302656, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37966427

RESUMEN

A stimuli-responsive protein self-assembly offers promising utility as a protein nanocage for biotechnological and medical applications. Herein, the development of a virus-like particle (VLP) that undergoes a transition between assembly and disassembly under a neutral and acidic pH, respectively, for a targeted delivery is reported. The structure of the bacteriophage P22 coat protein is used for the computational design of coat subunits that self-assemble into a pH-responsive VLP. Subunit designs are generated through iterative computational cycles of histidine substitutions and evaluation of the interaction energies among the subunits under an acidic and neutral pH. The top subunit designs are tested and one that is assembled into a VLP showing the highest pH-dependent structural transition is selected. The cryo-EM structure of the VLP is determined, and the structural basis of a pH-triggered disassembly is delineated. The utility of the designed VLP is exemplified through the targeted delivery of a cytotoxic protein cargo into tumor cells in a pH-dependent manner. These results provide strategies for the development of self-assembling protein architectures with new functionality for diverse applications.


Asunto(s)
Bacteriófago P22 , Proteínas de la Cápside , Proteínas de la Cápside/metabolismo , Bacteriófago P22/química , Bacteriófago P22/metabolismo , Concentración de Iones de Hidrógeno
11.
Adv Sci (Weinh) ; 11(35): e2404993, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38994888

RESUMEN

Metal-organic frameworks (MOFs) have emerged as promising materials for triboelectric nanogenerators (TENGs), but the effects of ligand choice on triboelectric charge remain underexplored. Hence, this paper demonstrates the effect of single, binary, and ternary ligands on TENG performance of cobalt/cerium-based (Co─Ce) bimetallic MOFs utilizing 2-methylimidazole (2Melm), terephthalic acid (BDC), and benzene tricarboxylic acid (BTC) as ligands. The detailed structural characterization revealed that varying ligand chemistries led to distinct MOF features affecting TENG performance. Single ligand bimetallic MOFs (designated as CoCe-2MeIm, CoCe-BDC, CoCe-BTC) has lower performance than binary ligand (designated as CoCe-2MeIm-BDC, CoCe-2MeIm-BTC, CoCe-BDC-BTC) and ternary ligand MOFs (designated as CoCe-2MeIm-BDC-BTC). Among all, the binary ligand MOF, CoCe-2MeIm-BTC, shows the best results (598 V, 26.7 µA) due to the combined effect of imidazole ring and (─COO─) groups. This is attributed to lone pairs on nitrogen atoms and a delocalized π-electron system in imidazole system in this material. CoCe-BTC has the lowest results (31 V, 3.2 µA) due to the bulkier nature of the electron-withdrawing (─COO─) groups and their impact on the π-electron system of the benzene ring. This study showcases the potential of ligand chemistry manipulation to control triboelectric charge and thereby enhance MOF-based TENG performance.

12.
Antioxidants (Basel) ; 13(6)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38929086

RESUMEN

Gamma-aminobutyric acid (GABA) is a non-protein amino acid that is found in the brain and central nervous system of animals as an inhibitory neurotransmitter. It has been shown to have a variety of physiological functions, including stress reduction and immune enhancement. This study investigated the effects of dietary supplementation with GABA on growth, serum biochemistry, innate immunity, and disease resistance in juvenile olive flounders (Paralichthys olivaceus) challenged with Edwardsiella tarda under high-stocking density. A control diet and three experimental diets were prepared, with 150 mg/kg (GABA150), 200 mg/kg (GABA200), and 250 mg/kg (GABA250) of GABA added to each diet, respectively. Each experimental diet was fed to olive flounders in triplicate with an initial weight of 12.75 g ± 0.3 g in 40 L tanks at two stocking densities: normal density (20 fish/tank) and high density (40 fish/tank). After 8 weeks of the feeding trial, growth, feed utilization, whole-body proximate compositions, blood analyses, and non-specific immune responses were measured, and challenge tests were performed. There were no significant differences in the weight gain (WG) and specific growth rate (SGR) among fish fed the GABA-supplemented diets at the two stocking densities. However, the normal-density groups showed significantly higher WG and SGR than the high-density groups (p < 0.05). There was no significant difference in feed efficiency and protein efficiency ratio among all groups. Moreover, there was no significant difference in the whole-body proximate composition analysis (p > 0.05). There were no significant differences in cortisol levels in fish fed the GABA at both densities, but the high-density group showed a significantly higher cortisol than the low-density group. Blood GABA significantly increased in a dose-dependent manner regardless of the density groups (p < 0.05). Superoxide dismutase activity showed significantly higher levels than the control group, but there was no significant effect of the stocking densities in fish fed the GABA diets (p < 0.05). Myeloperoxidase activities in fish fed the GABA200 and GABA250 diets showed significantly higher levels at both of the stocking densities (p < 0.05). Lysozyme activity was significantly higher in the GABA150 group than in the CON, GABA200, and GABA250 groups (p < 0.05). After 15 days of challenge tests with Edwardsiella tarda, the cumulative survival rates of the GABA150, GABA200, and GABA250 groups were significantly higher than that of the CON group (p < 0.05). The results suggested that the optimal dietary GABA level for juvenile olive flounder culture is 150 mg/kg, regardless of rearing density, to enhance growth, immunity, and disease resistance.

13.
Adv Mater ; 36(19): e2311029, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38299366

RESUMEN

Practical application of triboelectric nanogenerators (TENGs) has been challenging, particularly, under harsh environmental conditions. This work proposes a novel 3D-fused aromatic ladder (FAL) structure as a tribo-positive material for TENGs, to address these challenges. The 3D-FAL offers a unique materials engineering platform for tailored properties, such as high specific surface area and porosity, good thermal and mechanical stability, and tunable electronic properties. The fabricated 3D-FAL-based TENG reaches a maximum peak power density of 451.2 µW cm-2 at 5 Hz frequency. More importantly, the 3D-FAL-based TENG maintains stable output performance under harsh operating environments, over wide temperature (-45-100 °C) and humidity ranges (8.3-96.7% RH), representing the development of novel FAL for sustainable energy generation under challenging environmental conditions. Furthermore, the 3D-FAL-based TENG proves to be a promising device for a speed monitoring system engaging reconstruction in virtual reality in a snowy environment.

14.
Antioxidants (Basel) ; 12(8)2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37627488

RESUMEN

An 8-week feeding trial was executed to evaluate the efficacy of four functional feed additives in replacing antibiotics in juvenile olive flounder, Paralichthys olivaceus, fed with a low-fish-meal diet. A basal diet without feed additives was used as a control (CON); other diets were formulated by supplementing 0.50% taurine (TW), 0.30% peptide (PT), 0.23% mineral water (MW), 0.35% yeast-extracted nucleotides (GRO), 0.35% GRO + 0.50% taurine (GROTW), 0.35% GRO + 0.30% peptide (GROPT) and 0.35% GRO + 0.23% mineral water (GROMW) into the basal diet; in addition, one diet was supplemented with oxytetracycline (OTC) at 0.5% as a positive control. Triplicate groups of 25 fish with an average weight of 5.15 ± 0.06 g (mean ± SD) were fed one of the nine experimental diets. At the end of the feeding trial, the weight gain, specific growth rate and protein efficiency ratio of fish fed the GRO, GROMW, GROPT and GROTW diets were significantly higher than those of fish fed the CON diet (p < 0.05). The feed efficiency of fish fed the GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the TW and OTC diets. However, the survival, hepatosomatic index, viscerosomatic index and condition factor of fish, as well as their whole-body proximate composition, were not significantly affected by the experimental diets (p > 0.05). The serum glutamic pyruvic transaminase of fish fed the GROPT diet was significantly lower than that of fish fed the CON diet. However, glutamic oxaloacetic transaminase, glucose and total protein were not significantly affected by the experimental diets (p > 0.05). The serum superoxide dismutase activity of fish fed the PT, TW, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON diet. The lysozyme activity of fish fed the PT, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON and OTC diets. The myeloperoxidase activity of fish fed the TW, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON, PT and MW diets (p < 0.05). The flounder growth hormone gene expression of fish fed the TW, GRO, GROMW, GROPT, GROTW and OTC diets was significantly higher than that of fish fed the CON, PT and MW diets (p < 0.05). The interleukin 1ß and interleukin 10 gene expressions of fish fed the GRO, GROMW, GROPT and GROTW diets were significantly higher than those of fish fed the CON, PT, TW and MW diets (p < 0.05). Intestinal histology showed a significantly higher villi length for fish fed the GRO, GROMW, GROPT and GROTW diets compared to that of fish fed the CON diet (p < 0.05). Digestive enzyme activities such as trypsin activity were significantly higher in fish fed the GROMW, GROPT and GROTW diets than those in the rest of the diet groups (p < 0.05). Amylase activity in fish fed the MW, GRO, GROMW, GROPT, GROTW and OTC diets was significantly higher than that of fish fed the PT, TW and CON diets (p < 0.05). On the other hand, the lipase activity of fish fed the TW, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON, PT, MW and OTC diets (p < 0.05). The cumulative survival rate of fish fed the PT, GROTW, GROPT and GROMW diets was significantly higher than that of fish fed the CON, TW and MW diets after thirteen days of the challenge testing. Overall, the results demonstrate that the GRO, GROMW, GROPT and GROTW diets could be beneficial feed additives to replace antibiotics in juvenile olive flounder fed low-fish-meal diets.

15.
Sci Rep ; 13(1): 4905, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36966189

RESUMEN

In the present study, various statistical and machine learning (ML) techniques were used to understand how device fabrication parameters affect the performance of copper oxide-based resistive switching (RS) devices. In the present case, the data was collected from copper oxide RS devices-based research articles, published between 2008 to 2022. Initially, different patterns present in the data were analyzed by statistical techniques. Then, the classification and regression tree algorithm (CART) and decision tree (DT) ML algorithms were implemented to get the device fabrication guidelines for the continuous and categorical features of copper oxide-based RS devices, respectively. In the next step, the random forest algorithm was found to be suitable for the prediction of continuous-type features as compared to a linear model and artificial neural network (ANN). Moreover, the DT algorithm predicts the performance of categorical-type features very well. The feature importance score was calculated for each continuous and categorical feature by the gradient boosting (GB) algorithm. Finally, the suggested ML guidelines were employed to fabricate the copper oxide-based RS device and demonstrated its non-volatile memory properties. The results of ML algorithms and experimental devices are in good agreement with each other, suggesting the importance of ML techniques for understanding and optimizing memory devices.

16.
Animals (Basel) ; 12(3)2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35158571

RESUMEN

Recent research is increasingly shedding light on the important role that microbial metabolites such as γ-aminobutyric acid (GABA) play in the context of nutrition, cognition, immune function, and the modulation of the gut microbiome. Yet, very few trials were conducted to assess the effects of its supplementation on biomarkers of fish health. Therefore, an eight-week feeding trial was devised to evaluate GABA supplementation in juvenile olive flounder, (Paralichthys olivaceus). A total of 630 fish with an average weight of 4.90 ± 0.10 g (±SD) were randomly assigned to one of seven triplicate groups and fed a non-GABA supplemented diet (CON, with 92 mg/kg GABA content), a positive control with 4 g/kg oxytetracycline (OTC), and five other diets supplemented with 50, 100, 150, 200 and 250 mg/kg GABA (corresponding to a total GABA content of 154, 229, 282, 327 and 352 mg/kg, respectively). Growth, blood chemistry, nonspecific immunity, digestive enzyme activity and disease resistance were assessed. The results showed that 100 and 150 mg/kg GABA supplementation consistently yielded significant improvements (p < 0.05) in growth, intestinal amylase, serum lysozyme, and survival against infection with Streptococcus iniae. Based on polynomial analysis, the optimal supplementation level was determined to be 237 mg/kg. These results support GABA as an important functional feed additive in juvenile olive flounder.

17.
Antibiotics (Basel) ; 11(2)2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35203732

RESUMEN

We investigated the three probiotic bacteria and a processed yeast (GroPro-Aqua) as the replacers of antibiotics in juvenile olive flounder. A total of seven diets were used, that is, one basal or control (CON) diet; and six other diets, of which, three diets were prepared by supplementing probiotic bacteria such as Bacillus subtilis WB60 (BSWB60) at 1 × 108 CFU/g diet, Bacillus subtilis SJ10 (BSSJ10) at 1 × 108 CFU/g diet, and Enterococcus faecium SH30 (EFSH30) at 1 × 107 CFU/g diet; one diet with processed yeast (GRO) at 0.35% diet; and two other diets were supplemented with oxytetracycline (OTC) and amoxicillin (AMO) at 4 g/kg of each. Triplicate groups of fish (average 12.1 g) were fed one of the diets for eight weeks. At the end of the feeding trial, the fish that were fed the probiotic bacteria-supplemented diets had a significantly higher final weight, weight gain, and specific growth rate compared to the CON, OTC, and AMO diets. Fish that were fed the GRO diet had significantly higher feed efficiency and protein efficiency ratios than those of the fish that were fed the CON diet. Serum glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, glucose, and total protein were not affected by the diets. Lysozyme activity in fish that were fed the BSSJ10, BSWB60, and EFSH30 diets were significantly higher compared to the CON and OTC diets, whereas myeloperoxidase activity of fish fed the BSWB60 and EFSH30 diets were significantly higher than those of fish fed the CON and AMO diets. Flounder growth hormone gene expressions of fish that were fed BSWB60 and GRO diets were significantly higher compared to the CON, OTC, and AMO diets. The interleukin-1ß gene expression of fish that were fed the BSSJ10, BSWB60, EFSH30, OTC, and GRO diets was significantly higher than those of fish fed the CON diet. The interleukin-10 gene expression of fish that were fed the BSSJ10, EFSH30, and GRO diets was significantly higher than those of fish fed the CON and AMO diets. Posterior intestinal histology of fish showed significantly higher villi length in fish that were fed the BSSJ10, BSWB60, EFSH30, and GRO diets compared to the CON diet. After 15 days of challenge test with pathogenic bacteria Edwardsiella tarda, the cumulative survival rate of fish that were fed the BSSJ10, BSWB60, EFSH30, and GRO diets were significantly higher than those of fish that were fed the CON diet. Overall, the results indicate that dietary supplementation of B. subtilis (108 CFU/g diet), E. faecium (107 CFU/g diet), and processed yeast (GroPro-Aqua at 0.35% diet) could replace the antibiotics in terms of improving growth, immunity, gut health, and disease resistance in juvenile olive flounder.

18.
Animals (Basel) ; 12(9)2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35565646

RESUMEN

The price of fish oil has reached a historical peak due to a consistent downward production trend, and therefore, the search for sustainable alternative sources has received great attention. This research was conducted to evaluate dietary micro-algae, Schizochytrium sp. (SC) as fish oil (FO) replacer in rainbow trout, Oncorhynchus mykiss. In the first trial, apparent digestibility coefficient (ADC) was 92.4% for dry matter, 91.4% for crude protein, and 94.2% for crude lipid in rainbow trout. In the second trial, six diets were formulated to replace FO at 0% (CON), 20% (T20), 40% (T40), 60% (T60), 80% (T80), and 100% (T100) with SC in the rainbow trout (3.0 ± 0.4 g, mean ± SD) diet. After eight weeks' feeding trial, weight gain (WG), specific growth rate (SGR), and feed efficiency (FE) of fish fed the T20 diet were significantly higher than those of fish fed other diets (p < 0.05). However, there were no significant differences in these parameters among those of fish fed CON, T40, T60, and T80 diets. Lysozyme activity of fish fed the T20 diet was significantly higher than those of fish fed other experimental diets (p < 0.05). After 10 days of disease challenge testing with pathogenic bacteria (Lactococcus garvieae 1 × 108 CFU/mL), the cumulative survival rate of fish fed the T20 diet was significantly higher than those of fish fed the CON, T80, and T100 diets. Therefore, these results suggest dietary microalgae SC is well-digested and could replace up to 80% of fish oil in the diet of rainbow trout without negative effects on growth and immune responses.

19.
Microsyst Nanoeng ; 8: 56, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35646385

RESUMEN

By exploiting ion transport phenomena in a soft and flexible discrete channel, liquid material conductance can be controlled by using an electrical input signal, which results in analog neuromorphic behavior. This paper proposes an ionic liquid (IL) multistate resistive switching device capable of mimicking synapse analog behavior by using IL BMIM FeCL4 and H2O into the two ends of a discrete polydimethylsiloxane (PDMS) channel. The spike rate-dependent plasticity (SRDP) and spike-timing-dependent plasticity (STDP) behavior are highly stable by modulating the input signal. Furthermore, the discrete channel device presents highly durable performance under mechanical bending and stretching. Using the obtained parameters from the proposed ionic liquid-based synaptic device, convolutional neural network simulation runs to an image recognition task, reaching an accuracy of 84%. The bending test of a device opens a new gateway for the future of soft and flexible brain-inspired neuromorphic computing systems for various shaped artificial intelligence applications.

20.
Opt Express ; 19(9): 8254-66, 2011 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-21643075

RESUMEN

The discrete layer-peeling algorithm (DLPA) requires to discretize the continuous medium into discrete reflectors to synthesize nonuniform fiber Bragg gratings (FBG), and the discretization step of this discrete model should be sufficiently small for synthesis with high accuracy. However, the discretization step cannot be made arbitrarily small to decrease the discretization error, because the number of multiplications needed with the DLPA is proportional to the inverse square of the layer thickness. We propose a numerically extrapolated time domain DLPA (ETDLPA) to resolve this tradeoff between the numerical accuracy and the computational complexity. The accuracy of the proposed ETDLPA is higher than the conventional time domain DLPA (TDLPA) by an order of magnitude or more, with little computational overhead. To be specific, the computational efficiency of the ETDLPA is achieved through numerical extrapolation, and each addition of the extrapolation depth improves the order of accuracy by one. Therefore, the ETDLPA provides us with computationally more efficient and accurate methodology for the nonuniform FBG synthesis than the TDLPA.


Asunto(s)
Algoritmos , Modelos Teóricos , Refractometría/instrumentación , Refractometría/métodos , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Dinámicas no Lineales , Reproducibilidad de los Resultados
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