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1.
Anim Biosci ; 37(8): 1408-1417, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38419537

RESUMEN

OBJECTIVE: This study investigated the effects of dietary supplementation with lysolecithins (LPC) on growth performance, nutrient digestibility, blood profiles, immunity, and liver health in broiler chickens. METHODS: A cohort of 240 one-day-old male Arbor Acres broilers of comparable weight was divided into four treatment groups, each comprising six replicates of 10 birds. The groups were defined as follows: positive control with recommended metabolizable energy (PC+ME), negative control with 90 kcal/kg reduced ME (NC+ME), PC supplemented with 300 mg/kg LPC (PC+LPC), and NC supplemented with 300 mg/kg LPC (NC+LPC). RESULTS: LPC supplementation led to a statistically significant reduction in the feed conversion ratio (p = 0.05) and a decrease in the proportion of abdominal fat and the liver (p<0.05). Digestibility of dry matter was also enhanced (p<0.05). Malondialdehyde concentrations in the liver were significantly reduced by LPC (p<0.01), with a noteworthy interaction between energy levels and LPC affecting this reduction (p<0.05). Serum levels of interleukin-6 were reduced on day 21, and both endotoxin and interleukin-6 levels were lower on day 42. Notably, a significant interaction was observed between the energy levels and LPC on relative liver weight and endotoxin concentrations in the serum (p<0.05). CONCLUSION: The study concluded that LPC positively affects growth performance, nutrient digestibility, immune response, and antioxidative capacity in broiler chickens, affirming its value as a beneficial feed additive in poultry nutrition.

2.
Anim Nutr ; 15: 297-306, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38033609

RESUMEN

Medium-chain fatty acids and their derivatives are natural ingredients that support immunological functions in animals. The effects of glycerol monolaurate (GML) on intestinal innate immunity and associated molecular mechanisms were investigated using a chicken embryo model. Sixty-four Arbor Acres broiler embryos were randomly allocated into four groups. On embryonic day 17.5, the broiler embryos were administered with 9 mg of GML, which was followed by a 12-h incubation period and a 12-h challenge with 32 µg of lipopolysaccharide (LPS). On embryonic day 18.5, the jejunum and ileum were harvested. Results indicated that GML reversed the LPS-induced decline in villus height and upregulated the expression of mucin 2 (P < 0.05). GML decreased LPS-induced malondialdehyde production and boosted antioxidant enzyme activity (P < 0.05). GML alleviated LPS-stimulated intestinal secretion of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) (P < 0.05). GML also normalized LPS-induced changes in the gene expression of Toll-like receptor 4, nuclear factor kappa-B p65 (NF-κB p65), cyclooxygenase-2, NOD-like receptor protein 3, IL-18, zonula occludens 1, and occludin (P < 0.05). GML enhanced as well the expression of AMP-activated protein kinase α1 and claudin 1 (P < 0.05). In conclusion, GML improved intestinal morphology and antioxidant status by alleviating inflammatory responses and modulating NF-κB signaling in LPS-challenged broiler embryos.

3.
Sci Data ; 10(1): 594, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37679362

RESUMEN

Chickens are remarkably versatile animals that are used as model organisms for biomedical research. Here, we performed metabolomic and RNA sequencing (RNA-Seq) transcriptomic analyses of the hypothalamus, liver tissue and serum of poultry with different genetic backgrounds, providing detailed information for hypothalamus and liver tissue at the transcriptional level and for liver tissue and serum at the metabolite level. We present two datasets generated from 36 samples from three poultry breeds using high-throughput RNA-Seq and liquid chromatography coupled with mass spectrometry acquisition (LC/MS). The transcriptomic and metabolomic data obtained for poultry of different genetic backgrounds will be a valuable resource for further studies on this model organism.


Asunto(s)
Aves de Corral , Transcriptoma , Animales , Pollos/genética , Perfilación de la Expresión Génica , Metabolómica , Aves de Corral/genética
4.
ACS Macro Lett ; 12(8): 1045-1051, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37440526

RESUMEN

We report the use of l-aspartic acid chiral ionic hydrogen bonds to drive liquid-liquid phase separation (LLPS) and precision two-dimensional electrostatic self-assembly in photo-RAFT aqueous polymerization-induced self-assembly (photo-PISA). Homopolymerization can yield salt-resistant, 3 nm ultrafine fibril-structured 5 nm ultrathin lamellae via LLPS, a left-to-right-handed chirality transition, and a droplets-to-lamellae transition. Like-charge block copolymerization leads to supercharged yet identical fibril-structured ultrathin lamellae, also, via LLPS, the left-to-right chirality transition and the droplets-to-lamellae transition. Ultrafine structures maintain intactness upon the seeded polymerization of the oppositely charged monomer. This work demonstrates that amino acid chiral ionic hydrogen bonds are powerful for the precision synthesis of salt-resistant ultrathin membrane nanomaterials.

5.
Entropy (Basel) ; 24(12)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36554230

RESUMEN

The gravitational search algorithm is a global optimization algorithm that has the advantages of a swarm intelligence algorithm. Compared with traditional algorithms, the performance in terms of global search and convergence is relatively good, but the solution is not always accurate, and the algorithm has difficulty jumping out of locally optimal solutions. In view of these shortcomings, an improved gravitational search algorithm based on an adaptive strategy is proposed. The algorithm uses the adaptive strategy to improve the updating methods for the distance between particles, gravitational constant, and position in the gravitational search model. This strengthens the information interaction between particles in the group and improves the exploration and exploitation capacity of the algorithm. In this paper, 13 classical single-peak and multi-peak test functions were selected for simulation performance tests, and the CEC2017 benchmark function was used for a comparison test. The test results show that the improved gravitational search algorithm can address the tendency of the original algorithm to fall into local extrema and significantly improve both the solution accuracy and the ability to find the globally optimal solution.

6.
Sensors (Basel) ; 22(17)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36081109

RESUMEN

In this paper, a robust differential game guidance law is proposed for the nonlinear zero-sum system with unknown dynamics and external disturbances. First, the continuous-time nonlinear zero-sum differential game problem is transformed into solving the nonlinear Hamilton-Jacobi-Isaacs equation, a time-varying cost function is developed to reflect the fixed terminal time, and the robust guidance law is developed to compensate for the external disturbance. Then, a novel neural network identifier is designed to approximate the unknown nonlinear dynamics with online weight tuning. Subsequently, an online critic neural network approximator is presented to estimate the cost function, and time-varying activation functions are considered to deal with the fixed final time problem. An adaptive weight tuning law is given, where two additional terms are added to ensure the stability of the closed-loop nonlinear system and so as to meet the terminal cost at a fixed final time. Furthermore, the uniform ultimate boundedness of the closed-loop system and the critic neural network weights estimation error are proven based upon the Lyapunov approach. Finally, some simulation results are presented to demonstrate the effectiveness of the proposed robust differential game guidance law for nonlinear interception.


Asunto(s)
Redes Neurales de la Computación , Dinámicas no Lineales , Algoritmos , Simulación por Computador , Retroalimentación
7.
Anim Biosci ; 35(12): 1904-1910, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35760403

RESUMEN

OBJECTIVE: This study aimed to investigate the effects of corticotropin-releasing factor (CRF) on the feed intake of broiler chickens and explore its influencing mechanism. METHODS: The study included two trials. In trial 1, 32 male broiler chickens (Arbor Acres, Gallus gallus domesticus) were given ventricle buried tubes, and they were allowed to recover for 3 days. At 8:00 AM, intracerebroventricular (ICV) injection with CRF or normal saline was performed in 10-day-old broiler chickens, which were divided into the 5, 10, and 20 µg and control (normal saline) groups according to the dose of CRF injection. In trial 2, chickens were divided into the 10 µg and control group (physiological saline) to repeat trial 1. RESULTS: Results of trial 1 showed that the cumulative amount of feed intake in the 10 or 20 µg groups was considerably lower than that of the control group after ICV injection with CRF. The lowest amount of feed intake was obtained with the addition of 10 µg of CRF. In trial 2, the expression of ghrelin in the hypothalamus injected with 10 µg of CRF increased significantly, but the expression of ghrelin in various sections of the small intestine considerably decreased. The expression of CRF receptor subtypes 1 (CRFR1) in the hypothalamus and some parts of the small intestine remarkably increased, and the expression of CRF receptor subtypes 2 (CRFR2) increased only in the duodenum, whereas the expression of growth hormone secretagogue receptor (GHSR-1α) in the jejunum and ileum increased considerably after ICV injection of 10 µg of CRF. CONCLUSION: The CRF at 10 µg increased ghrelin expression in the hypothalamus and CRFR1 expression in the small intestine, and this phenomenon was related to the suppressed feed intake of broiler chickens.

8.
Front Nutr ; 9: 868093, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35571886

RESUMEN

This study was conducted to investigate the effects of Bacillus licheniformis DSM5749 on the production performance and intestinal health in laying hens. A total of 32-week-old laying hens (Hyline Brown) were randomly assigned to two dietary groups (10 replicates of 27 laying hens), namely, basal diet and basal diet complemented with 200 g/t B. licheniformis (3.2 × 109 CFU/kg). The trial lasted for 8 weeks, and samples were collected at the last week. Results revealed that B. licheniformis DSM5749 significantly improved laying performance, including an increase in egg production rate and average daily egg yield, and a decrease in the feed-to-egg ratio during the entire 8-week experimental period (P < 0.05). B. licheniformis DSM5749 increased the levels of superoxide dismutase and glutathione peroxidase in the liver and decreased the IL-1 level in the serum (P < 0.05). In addition, the integrity of intestinal morphology (villus height, crypt depth, and villus height/crypt depth), tight junctions (ZO-1, Claudin-1, and Occludin), and lipase vitality in the intestine were potentiated by B. licheniformis DSM5749 in laying hens (P < 0.05). B. licheniformis DSM5749 decreased the Firmicutes/Bacteroidetes ratio (P < 0.05) in the cecum. Furthermore, B. licheniformis DSM5749 modulated the microbiota in the cecum of the laying hens, increased the relative abundance of beneficial bacteria (e.g., Prevotella) at the genus level and decreased the relative abundance of potential pathogens (e.g., Desulfovibrio). In conclusion, B. licheniformis DSM5749 can improve laying performance, promote intestinal health, affect the composition of cecal microorganisms, and regulate the intestinal micro-ecological balance, making B. licheniformis a good probiotic candidate for application in the laying hens industry.

9.
Chem Commun (Camb) ; 58(48): 6793-6796, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35615871

RESUMEN

We present a template strategy for precision synthesis of "complex coacervates-in-dodecyl atmosphere" ultrathin lamellae possessing exceptional shape-preservation and charge-tolerance properties.

10.
Nonlinear Dyn ; 109(1): 265-284, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35283556

RESUMEN

In the absence of specific drugs and vaccines, the best way to control the spread of COVID-19 is to adopt and diligently implement effective and strict anti-epidemic measures. In this paper, a mathematical spread model is proposed based on strict epidemic prevention measures and the known spreading characteristics of COVID-19. The equilibria (disease-free equilibrium and endemic equilibrium) and the basic regenerative number of the model are analyzed. In particular, we prove the asymptotic stability of the equilibria, including locally and globally asymptotic stability. In order to validate the effectiveness of this model, it is used to simulate the spread of COVID-19 in Hubei Province of China for a period of time. The model parameters are estimated by the real data related to COVID-19 in Hubei. To further verify the model effectiveness, it is employed to simulate the spread of COVID-19 in Hunan Province of China. The mean relative error serves to measure the effect of fitting and simulations. Simulation results show that the model can accurately describe the spread dynamics of COVID-19. Sensitivity analysis of the parameters is also done to provide the basis for formulating prevention and control measures. According to the sensitivity analysis and corresponding simulations, it is found that the most effective non-pharmaceutical intervention measures for controlling COVID-19 are to reduce the contact rate of the population and increase the quarantine rate of infected individuals.

11.
Physica A ; 590: 126717, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34924686

RESUMEN

The global spread of COVID-19 has not been effectively controlled, posing a huge threat to public health and the development of the global economy. Currently, a number of vaccines have been approved for use and vaccination campaigns have already started in several countries. This paper designs a mathematical model considering the impact of vaccination to study the spread dynamics of COVID-19. Some basic properties of the model are analyzed. The basic reproductive number ℜ 1 of the model is obtained, and the conditions for the existence of endemic equilibria are provided. There exist two endemic equilibria when ℜ 1 < 1 under certain conditions, which will lead to backward bifurcation. The stability of equilibria are analyzed, and the condition for the backward bifurcation is given. Due to the existence of backward bifurcation, even if ℜ 1 < 1 , COVID-19 may remain prevalent. Sensitivity analysis and simulations show that improving vaccine efficacy can control the spread of COVID-19 faster, while increasing the vaccination rate can reduce and postpone the peak of infection to a greater extent. However, in reality, the improvement of vaccine efficacy cannot be realized in a short time, and relying only on increasing the vaccination rate cannot quickly achieve the control of COVID-19. Therefore, relying only on vaccination may not completely and quickly control COVID-19. Some non-pharmaceutical interventions should continue to be enforced to combat the virus. According to the sensitivity analysis, we improve the model by including some non-pharmaceutical interventions. Combining the sensitivity analysis with the simulation of the improved model, we conclude that together with vaccination, reducing the contact rate of people and increasing the isolation rate of infected individuals will greatly reduce the number of infections and shorten the time of COVID-19 spread. The analysis and simulations in this paper can provide some useful suggestions for the prevention and control of COVID-19.

12.
Micromachines (Basel) ; 12(11)2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34832785

RESUMEN

In robot inertial navigation systems, to deal with the problems of drift and noise in the gyroscope and accelerometer and the high computational cost when using extended Kalman filter (EKF) and particle filter (PF), a complementary filtering algorithm is utilized. By combining the Inertial Measurement Unit (IMU) multi-sensor signals, the attitude data are corrected, and the high-precision attitude angles are obtained. In this paper, the quaternion algorithm is used to describe the attitude motion, and the process of attitude estimation is analyzed in detail. Moreover, the models of the sensor and system are given. Ultimately, the attitude angles are estimated by using the quaternion extended Kalman filter, linear complementary filter, and Mahony complementary filter, respectively. The experimental results show that the Mahony complementary filtering algorithm has less computational cost than the extended Kalman filtering algorithm, while the attitude estimation accuracy of these two algorithms is similar, which reveals that Mahony complementary filtering is more suitable for low-cost embedded systems.

13.
ACS Macro Lett ; 10(11): 1410-1415, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-35549018

RESUMEN

Macromolecular crowding plays a key role in liquid-phase condensation of proteins and membraneless organelles yet is largely unexplored for artificial liquid materials. Herein, we present a strategy for direct access to multiphase liquid condensates with individual charged/neutral subdomains, by introducing macromolecular crowding to our previous protocol of liquid-liquid phase-separation-driven polymerization-induced electrostatic self-assembly (LLPS-PIESA). We show that reversible addition fragmentation chain transfer (RAFT) aqueous dispersion photo-copolymerization of a charged monomer with a specific neutral monomer, in the presence of a polar macrochain transfer agent (CTA) and an oppositely charged polyion, can induce self-sorting and macromolecular crowding. LLPS-PIESA proceeds via liquid-phase condensation of as-assembled nascent clusters up to biologically important nanostructured multiphase condensates with individual charged/neutral subdomains.


Asunto(s)
Proteínas , Iones , Sustancias Macromoleculares , Polimerizacion , Electricidad Estática
14.
ACS Macro Lett ; 10(7): 780-785, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35549188

RESUMEN

We present the nanostructured multiphase condensation of complex coacervates in the dynamic evolving aqueous medium of liquid-liquid phase separation driven polymerization-induced electrostatic self-assembly (LLPS-PIESA). We show that the parent droplets evolve into nanostructured coacervate-in-coacervate multiphase condensates with diverse morphologies, such as dandelions, worms, lamellae, vesicles, and vesicle polymers, upon the kinetically dictated recruitment of anionic free chains, cationic growing chains, and nascent clusters from the dynamic evolving aqueous medium of LLPS-PIESA, under the interplay of electrostatic and arginine-like salt bridge interactions.


Asunto(s)
Nanoestructuras , Polímeros , Cationes , Polimerizacion , Electricidad Estática
15.
J Anim Sci ; 98(7)2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32599620

RESUMEN

Glucocorticoids (GCs) induce the activation of the central adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling pathway in birds. In this study, we aimed to investigate the effects of corticosterone (CORT) supplemented in diet on the central AMPK signaling pathway in broilers. The average daily gain was reduced by CORT treatment, and the average daily feed intake remained unchanged. Plasma glucose, triglyceride, total cholesterol, and CORT contents were increased by CORT administration. In addition, CORT treatment decreased the relative weights of heart, spleen, and bursa and increased the relative weights of liver and abdominal fat. The glycogen contents in the liver and breast muscle were higher in the chicks treated with CORT. CORT treatment upregulated the gene expression of mammalian target of rapamycin, glucocorticoid receptor, AMPKα2, neuropeptide Y(NPY), liver kinase B1 (LKB1), AMPKα1, and fatty acid synthase in the hypothalamus. Moreover, CORT treatment increased the protein levels of acetyl-coenzyme A carboxylase (ACC) phosphorylation and total AMPK and phosphorylated AMPK in the hypothalamus. Hence, CORT administration in the diet activated the LKB1-AMPK-NPY/ACC signaling pathway in the hypothalamus of broiler.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Pollos/fisiología , Corticosterona/administración & dosificación , Dieta/veterinaria , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/genética , Adenosina Monofosfato/metabolismo , Adenosina Monofosfato/farmacología , Animales , Pollos/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glucocorticoides/metabolismo , Hipotálamo/metabolismo , Masculino , Neuropéptido Y/metabolismo , Músculos Pectorales/efectos de los fármacos , Músculos Pectorales/crecimiento & desarrollo
16.
Chem Commun (Camb) ; 56(36): 4954-4957, 2020 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-32239069

RESUMEN

The noncovalent structural locking of thermoresponsive polyion complex micelles, nanowires, and vesicles can be implemented via hydrogen bonding assisted polyion complexation through polymerization-induced electrostatic self-assembly (PIESA) using an arginine-like cationic monomer.

17.
ACS Macro Lett ; 9(4): 454-458, 2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35648501

RESUMEN

Scalable synthesis of multicompartment polyion complex (PIC) systems has been achieved via visible light-initiated RAFT polymerization of cationic monomer in the presence of anionic diblock copolymer micelles in water at 25 °C. This polymerization-induced hierarchical electrostatic self-assembly (hierarchical PIESA) implements structural hierarchy via programmable self-assembly to form multicompartment PIC micelles and their monolayer colloidal nanosheets and nanocages. The anionic micelles play decisive roles in such a hierarchical PIESA to access biologically relevant yet otherwise inaccessible multicompartment PIC systems.

18.
Sensors (Basel) ; 19(4)2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30823611

RESUMEN

The active aircraft defense problem is investigated for the stochastic scenario wherein a defending missile (or a defender) is employed to protect a target aircraft from an attacking missile whose pursuit guidance strategy is unknown. For the purpose of identifying the guidance strategy, the static multiple model estimator (sMME) based on the square-root cubature Kalman filter is proposed, and each model represents a potential attacking missile guidance strategy. Furthermore, an estimation enhancement approach is provided by using pseudo-measurement. For each model in the sMME, the model-matched cooperative guidance laws for the target and defender are derived by formulating the active defense problem as a constrained linear quadratic problem, where an accurate defensive interception and the minimum evasion miss distance are both considered. The proposed adaptive cooperative guidance laws are the result of mixing the model-matched optimal cooperative guidance laws in the criterion of maximum a posteriori probability in the framework of the sMME. By adopting the adaptive cooperative guidance laws, the target can facilitate the defender's interception with the attacking missile with less control effort. Also, simulation results show that the proposed guidance laws increase the probability of successful target protection in the stochastic scenario compared with other defensive guidance laws.

19.
ACS Macro Lett ; 8(5): 623-628, 2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35619369

RESUMEN

We herein present sequence-controlled polymerization-induced self-assembly (PISA) via photoswitchable reversible addition-fragmentation chain transfer (RAFT) copolymerization of oppositely-charged monomers using polyethylene glycol chain transfer agent in water at 25 °C. Thorough block copolymerization leads to a polymerization-induced electrostatic self-assembly named ABC-mode polymerization-induced electrostatic self-assembly (PIESA), by which PEGylated (PEG, polyethylene glycol) polyion complex (PIC) spheres, lamellae, and vesicles are achieved. We demonstrate the inherent spontaneous zwitterionic alternating copolymerization nature, which leads to the charge-dictated alternating or gradient zwitterionic sequence. As such, we developed sequence-controlled synthesis of nanostructured block-gradient zwitterionic terpolymer PICs via complete zwitterionic copolymerization starting from photoswitched incomplete first polymerization, i.e., AB(BC)-mode PIESA. This sequence-controlled PISA method provides the unprecedented control of the low-dimensional polyelectrolyte complex nanostructure involving not only shape but also size and thickness of micrometer-sized ultrathin PIC vesicles and lamellae, without necessarily changing the whole chemical composition and degree of polymerization.

20.
ACS Macro Lett ; 8(12): 1564-1569, 2019 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-35619391

RESUMEN

Typical cyclic diblock polymers are synthesized from their linear precursors via the ring-closure strategy in dilute conditions. Here we demonstrate a pseudo-high-dilution condition strategy for the efficient synthesis of cyclic rod-coil diblock copolymer from its linear precursor in selective solvents. The critical association concentration (CAC) of linear precursor is used for the control of unimer concentration during cyclization, while high copolymer synthetic concentrations are achieved via the dynamic equilibrium between unimers and micelles. The effects of CAC and micelle concentration on cyclization yield are studied and pure cyclic rod-coil diblock copolymer was obtained after azide resin treatment. Property investigations show the cyclic rod-coil copolymer has a larger second virial coefficient than its linear counterpart and self-assembles in selective solvents to form larger but looser spherical micelles due to its constraint topological structure.

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