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1.
Sci Total Environ ; 931: 172920, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38701933

RESUMO

Scleractinian corals are capable of accumulating polycyclic aromatic hydrocarbons (PAHs) in reef environments; however, the mechanism behind their PAHs tolerance is unknown. This study investigated the occurrence and bioaccumulation of PAHs in coral reef ecosystems and examined the physiological responses induced by PAHs in coral hosts and their algal symbionts, the massive coral Galaxea fascicularis and branching coral Pocillopora damicornis. G. fascicularis had a higher PAHs accumulation capacity than P. damicornis. Both the coral hosts and algal symbionts preferentially accumulated acenaphthene, dibenzo(a,h)anthracene, and benzo(a)pyrene. The accumulated PAHs by G. fascicularis and P. damicornis hosts was accompanied by a reduction in detoxification ability. The accumulated PAHs could induce oxidative stress in P. damicorni hosts, thus G. fascicularis demonstrated a greater tolerance to PAHs compared to P. damicornis. Meanwhile, their algal symbionts had fewer physiological responses to accumulated PAHs than the coral hosts. Negative effects were not observed with benzo(a)pyrene. Taken together, these results suggest massive and branching scleractinian corals have different PAHs bioaccumulation and tolerance mechanisms, and indicate that long-term PAHs pollution could cause significant alterations of community structures in coral reef ecosystems.


Assuntos
Antozoários , Recifes de Corais , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Antozoários/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Bioacumulação , Monitoramento Ambiental , Simbiose
2.
Environ Sci Technol ; 58(21): 9091-9101, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38709279

RESUMO

People of all ages consume salt every day, but is it really just salt? Plastic nanoparticles [nanoplastics (NPs)] pose an increasing environmental threat and have begun to contaminate everyday salt in consumer goods. Herein, we developed a combined surface enhanced Raman scattering (SERS) and stimulated Raman scattering (SRS) approach that can realize the filtration, enrichment, and detection of NPs in commercial salt. The Au-loaded (50 nm) anodic alumina oxide substrate was used as the SERS substrate to explore the potential types of NP contaminants in salts. SRS was used to conduct imaging and quantify the presence of the NPs. SRS detection was successfully established through standard plastics, and NPs were identified through the match of the hydrocarbon group of the nanoparticles. Simultaneously, the NPs were quantified based on the high spatial resolution and rapid imaging of the SRS imaging platform. NPs in sea salts produced in Asia, Australasia, Europe, and the Atlantic were studied. We estimate that, depending on the location, an average person could be ingesting as many as 6 million NPs per year through the consumption of sea salt alone. The potential health hazards associated with NP ingestion should not be underestimated.


Assuntos
Análise Espectral Raman , Plásticos , Nanopartículas , Cloreto de Sódio/química
3.
Front Psychol ; 15: 1270246, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38362247

RESUMO

The results from studies on relationship between caffeine intake and risk of anxiety remains controversial, so we conducted a meta-analysis to summarize the evidence about the association between caffeine intake and risk of anxiety. Relevant articles were identified by researching PubMed, Web of Science, Cochrane library, Embase, CNKI, WANFANG DATA, SinoMed and VIP from the inception to December, 2022. Three investigators independently sifted through the literature, extracted the data, and evaluated the quality of the included studies based on predetermined selection criteria and assessed articles with Risk of bias assessment tool for Cochrane systematic reviews and analytical cross-sectional study quality assessment tool from JBI PACES. After assessing the quality of the literature, meta-analysis was performed using Revman 5.4 and Stata 12.0. Data were obtained from eight articles, and 546 participants from 14 studies in eight articles from healthy populations were included in the caffeine-anxiety analyses. As the scales used to assess anxiety vary in the literature, we chose standardized mean difference as the outcome indicator. In terms of overall effect, the results of the meta-analysis showed that caffeine intake increased the risk of anxiety [SMD = 0.94, 95% Cl = (0.28, 1.60), p < 0.05]. After suspecting that dose size might be responsible for the heterogeneity by sensitivity analysis, we performed subgroup analysis according to dose size and found that low-dose caffeine intake moderately increased the risk of anxiety [SMD = 0.61, 95%Cl = (0.42, 0.79), p < 0.05], whereas high-dose caffeine intake had a highly significant increase in the risk of anxiety [SMD = 2.86, 95%Cl = (2.50, 3.22), p < 0.05]. The results confirm that caffeine intake is associated with an elevated risk of anxiety in healthy individuals without psychiatric disorders, especially when the intake dose is greater than 400 mg.

4.
Int J Biol Macromol ; 260(Pt 2): 129635, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266860

RESUMO

Although androgen deprivation therapy (ADT) by the anti-androgen drug enzalutamide (Enz) may improve the survival level of patients with castration-resistant prostate cancer (CRPC), most patients may eventually fail due to the acquired resistance. The reprogramming of glucose metabolism is one type of the paramount hallmarks of cancers. PKM2 (Pyruvate kinase isozyme typeM2) is a speed-limiting enzyme in the glycolytic mechanism, and has high expression in a variety of cancers. Emerging evidence has unveiled that microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have impact on tumor development and therapeutic efficacy by regulating PKM2 expression. Herein, we found that lncRNA SNHG3, a highly expressed lncRNA in CRPC via bioinformatics analysis, promoted the invasive ability and the Enz resistance of the PCa cells. KEGG pathway enrichment analysis indicated that glucose metabolic process was tightly correlated with lncRNA SNHG3 level, suggesting lncRNA SNHG3 may affect glucose metabolism. Indeed, glucose uptake and lactate content determinations confirmed that lncRNA SNHG3 promoted the process of glycolysis. Mechanistic dissection demonstrated that lncRNA SNHG3 facilitated the advance of CRPC by adjusting the expression of PKM2. Further explorations unraveled the role of lncRNA SNHG3 as a 'sponge' of miR-139-5p and released its binding with PKM2 mRNA, leading to PKM2 up-regulation. Together, Our studies suggest that lncRNA SNHG3 / miR-139-5p / PKM2 pathway promotes the development of CRPC via regulating glycolysis process and provides valuable insight into a novel therapeutic approach for the disordered disease.


Assuntos
Benzamidas , MicroRNAs , Nitrilas , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração , RNA Longo não Codificante , Masculino , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Antagonistas de Androgênios , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Glicólise/genética , Glucose , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica
5.
Environ Sci Process Impacts ; 26(2): 451-460, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38289156

RESUMO

Microplastic (<5 mm) pollution has become a pressing environmental concern in recent years. The present study investigated the occurrence characteristics and assessed the ecological risk of microplastics in the surface water and sediment of the Chitian Reservoir, a drinking water source in Hainan province (China). The results indicated that microplastics were detected in the surface water and sediment of the Chitian Reservoir and its surrounding areas. The overall abundance of microplastics in the water was 3.05 ± 1.16 items per L and in the sediment was 0.15 ± 0.06 items per g dry weight, which is relatively low compared to other reservoirs in China. The dominant components of microplastics detected in the Chitian Reservoir were polypropylene (PP), rayon, and polyester. Physical morphology analysis of microplastics showed that fibers with small particle sizes (<1 mm) and white color were the predominant characteristics in both the surface water and sediment. The domestic sewage from surrounding residents and agricultural wastewater may be the primary sources of microplastics in the reservoir. Ecological risk assessment revealed that the overall pollution load index (PLI) in the surface water (0.65) and sediment (0.51) of the Chitian Reservoir and its surrounding area is at a low level. The potential ecological hazards (RI) of microplastics (0.13 to 336.78 in water; 0.23 to 465.93 in sediment) in most sites fall within the scope of level I, but those in a few sites are at level II due to the presence of polyvinyl chloride (PVC). This study enriches the data on microplastic pollution in inland reservoir systems, providing fundamental reference information for future ecotoxicological studies and the management of microplastic pollution control.


Assuntos
Água Potável , Poluentes Químicos da Água , Microplásticos , Plásticos/análise , Água Potável/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Água/análise , China
6.
Mikrochim Acta ; 191(2): 90, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214747

RESUMO

A novel mosaic structure Silica@C/Co@ZIF-67 composite was synthesized by successfully embedding Co nanoparticles on the surface of silica spheres with the help of thermoplastic polyethyleneimine by carbon-reduction. The ZIF-67 half-shell layer structure was synthesized by the in-situ growth of ZIF-67 on the surface of silica spheres through the coordination of 2-methylimidazole with Co metal nodes. The composite was used as a magnetic solid-phase extraction adsorbent combined with high performance liquid chromatography-ultraviolet detector (HPLC-UV) for the extraction and determination of benzoylurea insecticides (BUs) in vegetables and tea. Based on the presence of π-π, hydrophobic and hydrogen bonding interactions between Silica@C/Co@ZIF-67 and BUs, the BUs were rapidly captured by the composites resulting in high adsorption performance. Under the optimal extraction parameters, the linear ranges were 0.3-200 µg L-1 for diflubenzuron, 0.6-200 µg L-1 for chlorbenzuron, and 1.0-200 µg L-1 for triflumuron, teflubenzuron, and flufenoxuron, with correlation coefficients (R2) greater than 0.9991. The limits of detection (LODs) of the method were 0.1-0.3 µg L-1, and the relative standard deviations (RSDs) were 1.2-3.0% for intra-day and 2.6-4.6% for inter-day. In the spiked recovery experiments of vegetables and tea, the recoveries of the five kinds of BUs ranged from 75.8 to 112.9%. In addition, after 10 repetitions using Silica@C/Co@ZIF-67, the recoveries of the five kinds of BUs were still as high as 78.4 to 83.9%.


Assuntos
Diflubenzuron , Inseticidas , Inseticidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Chá/química , Dióxido de Silício
7.
RSC Adv ; 13(50): 35018-35025, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38046632

RESUMO

The coupling of hetero monolayers into van der Waals (vdW) heterostructures has become an effective way to obtain tunable physical and chemical properties of two dimensional (2D) materials. In this work, based on first principles calculations, we systematically explore the electronic and magnetic properties of a 2D VOCl2/PtTe2 heterostructure. Our results indicate that the ground state of the VOCl2/PtTe2 heterostructure is a ferromagnetic (FM) metal with large magnetic anisotropy energy, among which, the VOCl2 "sublayer" shows FM half metallic properties while the PtTe2 "sublayer" shows nonmagnetic metallic properties. The Curie temperature (TC) of VOCl2/PtTe2 is 111 K. Moreover, the FM-antiferromagnetic (AFM) phase transition can be obtained under biaxial strain. Our work provides an effective way to improve the performance of 2D monolayers in nano-electronic devices.

8.
Entropy (Basel) ; 25(12)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38136531

RESUMO

Based on the NTRU trapdoor used in NIST's Falcon, a signcryption scheme following the sign-then-encrypt paradigm is constructed. The existing partitioning technique based on Waters hash over the lattice can not complete the security reduction in the standard model for the signature part due to the "partiality" of the pre-image generated with the NTRU trapdoor. To address this, a variant of Waters hash over small integers is proposed and, the probability of the successful reduction is analyzed. The resulting signcryption achieves existential unforgeability under the adaptive chosen-message attacks. By utilizing the uniqueness of the secret and the noise in an NTRU instance, the tag used in encryption is eliminated. Furthermore, a method to construct tamper-sensitive lattice public key encryption is proposed. This approach implants the ciphertext-sensitive information into the lattice public key encryption and binds it to the encrypted information. The malleability to the public key ciphertext triggers the change of the message-signature pair so that the IND-CCA2 security of the entire ciphertext can be guaranteed by the signature for the message. Thanks to the rational design and the efficiency of the NTRU trapdoor, the computational overhead of the proposed scheme is reduced significantly compared to the existing lattice-based signcryption scheme, reaching orders of magnitude improvement in efficiency. The experiment shows that the proposed scheme is efficient.

9.
J Environ Manage ; 348: 119330, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37871548

RESUMO

Many soil and water conservation measures (SWCM) have been implemented in the Loess Plateau of China, and they have an impact on ecosystems all levels and involve complicated mechanisms. Previously, studies typically focused on a single factor's effect on diversity or productivity. With this background, the current investigation embarked on an extensive study, with vegetation survey conducted in the no measure plots (NM), vegetation measure plots (VM) and engineering measure plots (EM) in the Loess Plateau of China. We used structural equation models (SEM) to explain the mechanism by which SWCM affects plant productivity and diversity. VM have direct effects on plant diversity, and EM have direct effects on soil properties and community structure. The two measures also had indirect effects on plant functional traits and community structure. The results show that the changes in plant functional traits and community structure by SWCM decreased plant diversity, whereas the increase of productivity was primarily dominated by improvements in community structure, and we conclude that variability in plant diversity and productivity across different measures on the Loess Plateau was primarily due to the responses of different plants to variable soil properties and the community responses. It was also emphasized that vegetation measures were beneficial to the increase of biomass per plant, while engineering measures were more beneficial to the growth of dominant species. These findings provide a theoretical foundation for vegetation management and restoration after the application of different SWCM.


Assuntos
Conservação dos Recursos Hídricos , Ecossistema , Solo , Plantas , Biomassa , China
10.
Front Oncol ; 13: 1147805, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681027

RESUMO

Introduction: Immunogenic cell death (ICD) is a form of regulated cell death that activates an adaptive immune response in an immunocompetent host and is particularly sensitive to antigens from tumor cells. Kidney clear cell carcinoma (KIRC) is an immunogenic tumor with extensive tumor heterogeneity. However, no reliable predictive biomarkers have been identified to reflect the immune microenvironment and therapeutic response of KIRC. Methods: Therefore, we used the CIBERSORT and ESTIMATE algorithms to define three ICD clusters based on the expression of ICD-related genes in 661 KIRC patients. Subsequently, we identified three different ICD gene clusters based on the overlap of differentially expressed genes (DEGs) within the ICD clusters. In addition, principal component analysis (PCA) was performed to calculate the ICD scores. Results: The results showed that patients with reduced ICD scores had a poorer prognosis and reduced transcript levels of immune checkpoint genes regulated with T cell differentiation. Furthermore, the ICD score was negatively correlated with the tumor mutation burden (TMB) value of KICD. patients with higher ICD scores showed clinical benefits and advantages of immunotherapy, indicating that the ICD score is an accurate and valid predictor to assess the effect of immunotherapy. Discussion: Overall, our study presents a comprehensive KICD immune-related ICD landscape that can provide guidance for current immunotherapy and predict patient prognosis to help physicians make judgments about the patient's disease and treatment modalities, and can guide current research on immunotherapy strategies for KICD.

11.
J Chromatogr A ; 1707: 464324, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37634259

RESUMO

Hydrophobization and stability is crucial for the practical application of most metal-organic frameworks (MOFs) in extraction technique. In this study, a stable core-shell MOF@COF composite (NH2-MIL-101(Fe)@TAPB-FPBA-COF) was successfully prepared by Schiff base reaction and applied to solid-phase extraction (SPE) of hydrophobic flavonoids. Notably, the TAPB-FPBA-COF shell acts as a hydrophobic "shield", which not only improves the hydrophobicity and stability of hydrophilic NH2-MIL-101(Fe), but also makes the extraction efficiency of flavonoids from MOF@COF composite significantly higher than that of pure NH2-MIL-101(Fe) and TAPB-FPBA-COF. In addition, a sensitive analytical method with excellent linearities (0.1-500 ng mL-1, R2 ≥ 0.9967), low limits of detection (0.02-0.04 ng mL-1 for water; 0.04-0.07 ng mL-1 for grape juice; 0.06-0.08 ng mL-1 for honey), good repeatability (intra-day/inter-day precision are 1.86-5.37%/1.82-7.79%, respectively) and only 5 mg of adsorbent per cartridge was established by optimizing the SPE process combined with high performance liquid chromatography with ultraviolet-visible detector (HPLC-UV). Meanwhile, selectivity study and comparative experiments with the commercial C18 adsorbent showed that the MOF@COF adsorbent exhibited satisfactory extraction efficiency for flavonoids due to multiple interactions such as hydrogen bonding, hydrophobic, and π-π interactions. Finally, the good recoveries in grape juice (84.5-102.5%) and honey (87.5-104.6%) samples further validated the applicability of the proposed method in complex samples.


Assuntos
Estruturas Metalorgânicas , Flavonoides , Extração em Fase Sólida
12.
Sci Total Environ ; 899: 165571, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459992

RESUMO

Rice-vegetable rotations are dominant in (sub)-tropical agriculture worldwide. However, fate and risks of the insecticide flonicamid (FLO) and its main degradates (collectively called FLOMs) in multiple substrates from those cropping systems remain largely unknown. In this study, we characterized residual concentrations, driving factors, transport, and potential ecological risks of FLOMs in different substrates in 28 tropical rice-vegetable rotations. Concentrations (median) of FLOMs were 0.013-3.03 (0.42) ng g-1 in plants, 0.012-1.92 (0.23) ng g-1 in soil, 0.029-0.63 (0.126) µg L-1 in water, and 0.002-0.398 (0.055) ng g-1 in sediments. Flonicamid and its metabolite N-(4-trifluoromethylnicotinoyl) glycine were the dominant species in the four substrates (84.1 % to 88.5 %). Plants had the highest levels of FLOMs, with the highest bioconcentration factor in peppers. According to boosted regression trees coupled with a partial least squares structural equation model, levels and composition of FLOMs showed high spatiotemporal and crop-related patterns in different substrates, with patterns highly codetermined by agricultural practices (e.g., crop type and FLO/neonicotinoid/pyrethroid applications), substrate parameters (e.g., pH, organic matter or total organic carbon), and climate features (e.g., wet/dry seasons). Moreover, a fugacity method indicated differences in transport and partitioning patterns in different substrates during rice and vegetable planting periods. Integrated substrate risk assessment of FLOMs contamination was conducted based on species-sensitive distributions and substrate weight index. Although overall risks of FLOM contamination in tropical rice-vegetable rotations were negligible to low, the highest risks were in soils, vegetable planting periods, and a central intensively planted area.


Assuntos
Oryza , Verduras , Verduras/química , Oryza/metabolismo , Agricultura/métodos , Solo/química , China
13.
Heliyon ; 9(6): e16533, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37274694

RESUMO

Avoiding injury and ensuring safe evacuations of children in disasters has always been a central issue requiring close attention in policymaking. However, there is little behavioural data on children's evacuation on stairs. In this study, evacuation drills were conducted in a three-storey kindergarten in Dalian, China. The article explores the well-trained children's vertical evacuation behaviour on stairs and horizontal evacuation behaviour in other areas such as corridors and lobbies. According to the vertical behavioural evacuation data collected in this study, the mean speed of children aged 4-6 is 0.55 ± 0.12 m/s, and children of different age groups exhibit distinctive evacuation behaviours on stairs. The mean speed of children on a horizontal plane is 0.87 ± 0.22 m/s. Then, the relationship between behavioural data (movement time, density, velocity, and flow rate) is compared and analyzed. It is found that the density and flow rate of the crowd at the stairwell entrance and the exit are higher than that of adults, and the children's walking speed is relatively slow. This study can provide reference for safety design, evacuation strategies and evacuation simulation settings of multi-storey kindergartens.

14.
Nanotechnology ; 34(36)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37311448

RESUMO

The local surface plasmon resonance (LSPR) effect has been widely used in various nanophotonic applications. However, because the LSPR effect is highly sensitive to the structure and geometry, it is desirable to efficiently search viable geometries for predefined local field enhancement spectrum. Herein we present a generative adversarial network-based LSPR nanoantenna design scheme. By encoding the antenna structure information into an red-green-blue (RGB) color image, the corresponding nanoantenna structure can be inverse-designed to achieve the required enhancement spectrum of the local field. The proposed scheme can accurately offer the multiple geometry layout for the customized specific spectrum in seconds, which could be beneficial for fast design and fabrication of plasmonic nanoantenna.

15.
Opt Lett ; 48(12): 3283-3286, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319082

RESUMO

Topological edge states are a generic feature of topological insulators, and the long-range interactions, which break certain properties of topological edge states, are always non-negligible in real physical systems. In this Letter, we investigate the influence of next-nearest-neighbor (NNN) interactions on the topological properties of the Su-Schrieffer-Heeger (SSH) model by extracting the survival probabilities at the boundary of the photonic lattices. By introducing a series of integrated photonic waveguide arrays with different strengths of long-range interactions, we experimentally observe delocalization transition of light in SSH lattices with nontrivial phase, which is in good agreement with our theoretical predictions. The results indicate that the NNN interactions can significantly affect the edge states, and that the localization of these states can be absent in topologically nontrivial phase. Our work provides an alternative way to investigate the interplay between long-range interactions and localized states, which may stimulate further interest in topological properties in relevant structures.


Assuntos
Fótons , Análise por Conglomerados
16.
BMC Bioinformatics ; 24(1): 34, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36721089

RESUMO

BACKGROUND: As one of the fundamental problems in bioinformatics, the double digest problem (DDP) focuses on reordering genetic fragments in a proper sequence. Although many algorithms for dealing with the DDP problem were proposed during the past decades, it is believed that solving DDP is still very time-consuming work due to the strongly NP-completeness of DDP. However, none of these algorithms consider the privacy issue of the DDP data that contains critical business interests and is collected with days or even months of gel-electrophoresis experiments. Thus, the DDP data owners are reluctant to deploy the task of solving DDP over cloud. RESULTS: Our main motivation in this paper is to design a secure outsourcing computation framework for solving the DDP problem. We at first propose a privacy-preserving outsourcing framework for handling the DDP problem by using a cloud server; Then, to enable the cloud server to solve the DDP instances over ciphertexts, an order-preserving homomorphic index scheme (OPHI) is tailored from an order-preserving encryption scheme published at CCS 2012; And finally, our previous work on solving DDP problem, a quantum inspired genetic algorithm (QIGA), is merged into our outsourcing framework, with the supporting of the proposed OPHI scheme. Moreover, after the execution of QIGA at the cloud server side, the optimal solution, i.e. two mapping sequences, would be transferred publicly to the data owner. Security analysis shows that from these sequences, none can learn any information about the original DDP data. Performance analysis shows that the communication cost and the computational workload for both the client side and the server side are reasonable. In particular, our experiments show that PP-DDP can find optional solutions with a high success rate towards typical test DDP instances and random DDP instances, and PP-DDP takes less running time than DDmap, SK05 and GM12, while keeping the privacy of the original DDP data. CONCLUSION: The proposed outsourcing framework, PP-DDP, is secure and effective for solving the DDP problem.


Assuntos
Serviços Terceirizados , Humanos , Privacidade , Algoritmos , Biologia Computacional , Emoções
17.
Opt Lett ; 48(3): 554-557, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723529

RESUMO

Optical waveguides prepared by femtosecond laser direct writing have birefringent properties, which can affect polarization encoding and entanglement on chips. Here, we first propose a shape-stress dual compensation fabrication scheme to decrease birefringence. Ultralow birefringent waveguides (1 × 10-9) were obtained by controlling the cross sectional shape of the main waveguide and adjusting the position of the auxiliary lines. In addition, we prepared polarization-independent directional coupler and demonstrated the evolution of polarization-independent waveguide array with different polarized light. In the future, ultralow birefringent waveguides will be widely applied in polarization encoding and entangled quantum photonic integrated circuits.

18.
J Chromatogr A ; 1691: 463814, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36702034

RESUMO

Metal-organic framework (MOF) and covalent organic framework (COF) exhibit excellent extraction performance in sample pretreatment, but their wider application is hindered by some inherent drawbacks. Herein, we successfully synthesized a novel MOF@COF hybrid material with large specific surface area, good chemical stability and reusability, which is suitable as a solid phase extraction (SPE) sorbent for the efficient extraction of flavonoids. Importantly, due to the synergistic effect, the obtained MOF@COF hybrid material showing a higher extraction efficiency than individual MOF and COF. This is mainly due to the obtained MOF@COF hybrid material combines the high specific surface area of MOF and multiple interactions (hydrophobic interaction, hydrogen bonding and π-π stacking interaction) with flavonoids conferred by the COF structure. Then, a sensitive analytical method for flavonoids with ideal linear range (1-500 ng mL-1), low detection limit (0.15-0.41 ng mL-1) and good repeatability (2.64-6.20%) was developed under optimized conditions. In addition, the MOF@COF hybrid sorbent has better selectivity for hydrophobic targets containing multiple hydrogen bond acceptors/donors. Finally, the established method was applied to the determination of flavonoids in different food samples, and satisfactory recoveries (81.4-102.1%) were obtained, which initially confirmed its applicability.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Flavonoides , Extração em Fase Sólida/métodos , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção
19.
IEEE Trans Cybern ; 53(7): 4280-4291, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35468076

RESUMO

In this article, the proportional-integral observer design problem is studied for a class of multirate networked systems subject to constrained bit rate. The sensor sampling period is allowed to be different from the system updating period and, to facilitate the observer design, the underlying multirate system is cast into a general single-rate one by resorting to the lifting technique. In order to curb the communication burden and promote the data security, the encoding-decoding procedure is implemented on the sensor-to-observer channel to convert the measurement signals into binary codewords. A sufficient condition is first proposed to reveal the fundamental relationship between the bit-rate constraints and the decoding accuracy, and then the exponentially ultimate boundedness of the error dynamics is assessed with the aid of the Lyapunov method. Subsequently, the desired observer gains are determined by solving two optimization problems with the aim to achieve two distinct performance indices, namely, the smallest ultimate bound and the fastest decay rate. Finally, the validity of the developed observer design approach is thoroughly demonstrated via the simulation examples.


Assuntos
Comunicação , Simulação por Computador
20.
Environ Sci Pollut Res Int ; 30(10): 26998-27012, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36372860

RESUMO

Water use efficiency (WUE) is an effective indicator to study the coupling of terrestrial carbon and water cycles. The Tibetan Plateau (TP) is the most important ecological security barrier in China, and it is important to understand the characteristics of WUE and the change mechanism to study the carbon and water cycles of plateau ecosystems and the rational use of water resources. This study analyzes the spatial and temporal characteristics of WUE on the TP and the influence of climate factors on WUE based on the gross primary productivity (GPP) and evapotranspiration (ET) data from GLASS. The results show that from 1985 to 2018, the WUE of the TP is on the rise under the combined effect of GPP and ET; the regions with higher mean WUE values are the southeastern and eastern parts of the plateau, and the low value areas are the central and northwestern parts of the plateau. Compared with precipitation, WUE is influenced by temperature over a larger area. The correlations between precipitation and temperature and WUE in different eco-geographic regions are complex, and there is a threshold effect on the correlation between WUE and temperature and precipitation. Temperature is the main driver of WUE changes in HIIA and HIB1 regions, while precipitation has a greater impact on WUE changes in HIIC2, HIIC2, HIC2, HIID3, and HIIC regions. Precipitation, temperature, and elevation are the main factors explaining the variation of WUE in the TP. According to the risk detector, it can be determined that grassland vegetation in warm and humid steep areas of low and medium elevations is more able to maintain efficient use of water. Meanwhile, grasslands located in the shade of northern slopes have weaker transpiration, which is conducive to vegetation accumulation of growth water, and thus can ensure higher WUE. The related study can provide a reference for the response of vegetation WUE to global changes in key climatic regions.


Assuntos
Ecossistema , Pradaria , Tibet , Água , China , Carbono , Mudança Climática
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