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1.
Food Sci Nutr ; 12(6): 4049-4062, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873458

RESUMO

The primary objective of this investigation was to explore the beneficial impacts of Enteromorpha prolifera polysaccharide (EP) on dysglycemia in Zucker diabetic fatty (ZDF) rats, while also shedding light on its potential mechanism using 1H-NMR-based metabolomics. The results demonstrated a noteworthy reduction in fasting blood glucose (FBG, 46.3%), fasting insulin (50.17%), glycosylated hemoglobin A1c (HbA1c, 44.1%), and homeostatic model assessment of insulin resistance (HOMA-IR, 59.75%) following EP administration, while the insulin sensitivity index (ISI, 19.6%) and homeostatic model assessment of ß-cell function (HOMA-ß, 2.5-fold) were significantly increased. These findings indicate that EP enhances ß-cell function, increases insulin sensitivity, and improves insulin resistance caused by diabetes. Moreover, EP significantly reduced serum lipid levels, suggesting improvement of dyslipidemia. Through the analysis of serum metabolomics, 17 metabolites were found to be altered in diabetic rats, 14 of which were upregulated and 3 of which were downregulated. Notably, the administration of EP successfully reversed the abnormal levels of 9 out of the 17 metabolites. Pathway analysis further revealed that EP treatment partially restored metabolic dysfunction, with notable effects observed in valine, leucine, and isoleucine metabolism; aminoacyl-transfer RNA (tRNA) biosynthesis; and ketone body metabolism. These findings collectively indicate the potential therapeutic efficacy of EP in preventing glycemic abnormalities and improving insulin resistance. Thus, EP holds promise as a valuable treatment option for individuals with diabetes.

2.
Opt Express ; 30(3): 3876-3892, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209637

RESUMO

Continuous-variable quantum secret sharing (CVQSS) allows a legitimate user, i.e., the dealer, to share a string of secret keys with multiple distant users. These users cannot individually recover the dealer's secret key unless they work cooperatively. Although the theoretical security proof of CVQSS has been well established, its practical security and implementation still face challenges. In this paper, we suggest a practical scheme for CVQSS using plug-and-play (P&P) configuration and dual-phase-modulated coherent state (DPMCS). The proposed scheme, called P&P DPM-based CVQSS, waives the necessity that each user has to prepare respective coherent states with their own lasers, thereby eliminating synchronous loopholes caused by different lasers and reducing the complexity of deployment of the user's stations. Moreover, the local oscillator (LO) can be generated locally by the dealer so that the whole CVQSS system could be naturally immune to all LO-aimed attacks. We derive the security bounds for P&P DPM-based CVQSS by properly making most of the existing security analysis techniques of continuous-variable quantum key distribution (CVQKD). In addition, an experimental concept of P&P DPM-based CVQSS is also presented, which can be deemed a guideline for future implementation.

3.
Sci Rep ; 11(1): 21686, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737374

RESUMO

Security issues and attack management of optical communication have come increasingly important. Quantum techniques are explored to secure or protect classical communication. In this paper, we present a method for in-service optical physical layer security monitoring that has vacuum-noise level sensitivity without classical security loopholes. This quantum-based method of eavesdropping detection, similar to that used in conventional pilot tone systems, is achieved by sending quantum signals, here comprised of continuous variable quantum states, i.e. weak coherent states modulated at the quantum level. An experimental demonstration of attack detection using the technique was presented for an ideal fibre tapping attack that taps 1% of the ongoing light in a 10 dB channel, and also an ideal correlated jamming attack in the same channel that maintains the light power with excess noise increased by 0.5 shot noise unit. The quantum monitoring system monitors suspicious changes in the quantum signal with the help of advanced data processing algorithms. In addition, unlike the CV-QKD system which is very sensitive to channel excess noise and receiver system noise, the quantum monitoring is potentially more compatible with current optical infrastructure, as it lowers the system requirements and potentially allows much higher classical data rate communication with links length up to 100 s km.

4.
Light Sci Appl ; 9: 170, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082939

RESUMO

Optical fibre networks are advancing rapidly to meet growing traffic demands. Security issues, including attack management, have become increasingly important for optical communication networks because of the vulnerabilities associated with tapping light from optical fibre links. Physical layer security often requires restricting access to channels and periodic inspections of link performance. In this paper, we report how quantum communication techniques can be utilized to detect a physical layer attack. We present an efficient method for monitoring the physical layer security of a high-data-rate classical optical communication network using a modulated continuous-variable quantum signal. We describe the theoretical and experimental underpinnings of this monitoring system and the monitoring accuracy for different monitored parameters. We analyse its performance for both unamplified and amplified optical links. The technique represents a novel approach for applying quantum signal processing to practical optical communication networks and compares well with classical monitoring methods. We conclude by discussing the challenges facing its practical application, its differences with respect to existing quantum key distribution methods, and its usage in future secure optical transport network planning.

5.
Environ Sci Pollut Res Int ; 24(9): 8326-8335, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28161864

RESUMO

To effectively remove N and P from eutrophic water, the Phragmites australis after phytoremediation was harvested for preparation of modified biochar. The MgCl2-modified biochar (MPB) was successfully synthesized at 600 °C under N2 circumstance. The physiochemical characteristics, the adsorption capacity for N and P in the simulated solution, and their adsorption mechanism of MPB were then determined, followed by the treatment of eutrophic water of Tai lake and its inflow river from agricultural source. The results demonstrated that the MPB presented high adsorption capacity to both simulated NH4-N and PO4-P with the maximum adsorption capacity exceeding 30 and 100 mg g-1, respectively. The entire ammonium adsorption process could be described by a pseudo-second-order kinetic model whereas the phosphate adsorption process could be divided into three phases, as described by both intra-particle diffusion model and the pseudo-first-order kinetic. It was further found that the dominant mechanism for ammonium adsorption was Mg2+ exchange instead of functional groups and surface areas and the Mg-P precipitation was the main mechanism for phosphate adsorption. The MPB also showed high removal ratio of practical TP which reached nearly 90% for both the water in Tai lake and its agricultural source. It suggested that MPB based on harvested P. australis was a promising composite for eutrophic water treatment and it could deliver multiple benefits. Graphic abstract.


Assuntos
Compostos de Amônio/isolamento & purificação , Carvão Vegetal/química , Fosfatos/isolamento & purificação , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Difusão , Cinética , Cloreto de Magnésio , Poaceae , Soluções
6.
Bioresour Technol ; 193: 68-75, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26117237

RESUMO

Chlorella vulgaris, a marine microalgae strain adaptable to 0-50 g L(-1) of salinity, was selected for studying the coupling system of saline wastewater treatment and lipid accumulation. The effect of total nitrogen (T N) concentration was investigated on algal growth, nutrients removal as well as lipid accumulation. The removal efficiencies of TN and total phosphorus (TP) were found to be 92.2-96.6% and over 99%, respectively, after a batch cultivation of 20 days. To illustrate the response of lipid accumulation to nutrients removal, C. vulgaris was further cultivated in the recycling experiment of tidal saline water within the photobioreactor. The lipid accumulation was triggered upon the almost depletion of nitrate (<5 mg L(-1)), till the final highest lipid content of 40%. The nitrogen conversion in the sequence of nitrate, nitrite, and then to ammonium in the effluents was finally integrated with previous discussions on metabolic pathways of algal cell under nitrogen deficiency.


Assuntos
Chlorella vulgaris/metabolismo , Lipídeos/fisiologia , Microalgas/metabolismo , Nitratos/metabolismo , Cloreto de Sódio/metabolismo , Águas Residuárias/química , Compostos de Amônio/metabolismo , Redes e Vias Metabólicas/fisiologia , Nitritos/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Fotobiorreatores , Eliminação de Resíduos Líquidos/métodos
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