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1.
Anal Chem ; 96(5): 2078-2086, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38259249

RESUMO

A series of optically active helical poly(phenylacetylene)s (PPA-Pro1, PPA-Pro3, PPA-Pro6, PPA-Pro9, and PPA-Pro12) bearing different chain lengths of L-proline oligopeptide in the side chains were obtained by polymerizing the corresponding novel phenylacetylene monomers. The monomer adopted a trans-rich helix structure when the L-proline oligopeptide chain length was longer, according to the optical activities and 2D-NMR analysis. The helical structure could be maintained and significantly influenced the polymers' helical conformation by introducing the L-proline oligopeptide to the pendants. By the way, the morphology of PPA-Pro3 was observed by atomic force microscope (AFM) on highly oriented pyrolytic graphite (HOPG), and the information on the helix direction, pitch, and chain arrangement was obtained. Also, the chiral separation properties of these polymer-based chiral stationary phases (CSPs) were investigated using high-performance liquid chromatography (HPLC). The poly(phenylacetylene)s showed enhanced enantioseparation properties toward various racemates depending on the longer chain length of the L-proline oligopeptide in the pendants and the positive synergy between the helical backbone and helical side chains. Particularly, PPA-Pro9 showed comparable or even superior enantioseparation properties for racemates 2 and 9 to four commercial columns (Daicel Chiralpak or Chiralcel AD, AS, OD, and OT), indicating that these poly(phenylacetylene)-based CSPs have potential practical values. This work presented here provides inspiration for the further development of CSPs based on a new paradigm.

2.
Opt Lett ; 49(5): 1313-1316, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427001

RESUMO

Bound states in the continuum (BICs) provide an alternative way of trapping light at nanoscale. Although the last 10 years have witnessed tremendous progress on BICs from fundamentals to applications, nonreciprocal BICs and their potential applications have not been fully exploited yet. In this study, we demonstrated a one-way quasi-BIC by leveraging an all-dielectric magneto-optical (MO) metasurface. We show that the key point for achieving a one-way quasi-BIC is to excite a magnetization-induced leaky resonance. Here we adopt the longitudinal toroidal dipole (TD) resonance characterized by a vortex distribution of head-to-tail magnetic dipoles parallel to the plane of the MO metasurface. We show that, by breaking the time-reversal symmetry, at critical conditions, the TD resonance can be enhanced in the forward channel and perfectly canceled in the time-reversed channel, resulting in a one-way quasi-BIC. The demonstrated phenomena hold significant promise for practical applications such as magnetic field optical sensing, nonreciprocal optical switching, isolation, and modulation.

3.
Langmuir ; 40(21): 11329-11339, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38748512

RESUMO

The current membrane materials used for oil-water separation suffer from low separation efficiency and poor durability, and membrane contamination is also a key issue that must be addressed urgently. In this paper, a superhydrophilic PANI/Ag/TA@PVDF composite membrane with PANI-Ag NPs heterojunction structure was prepared via chelation and reduction of Ag+ by tannic acid (TA) and in situ growth of hydrochloric acid-doped polyaniline (PANI). TA endows the prepared composite membrane with excellent superhydrophilicity and underwater oleophobicity, remarkable oil-water separation capacity (the separation efficiency of more than 97% for soybean oil), and extraordinary antifouling properties. Notably, the range of photodegradation is expanded from UV to visible light by the construction of a Schottky heterostructure between PANI and Ag NPs, the photocatalytic degradation ability of composite membrane for organic pollutants has been improved obviously, and the degradation efficiency for crystal violet (CV) is 97.9%. Considering these merits, the PANI/Ag/TA@PVDF composite membrane provides an effective strategy to overcome the shortcomings of existing membrane materials, presenting enormous potential in the treatment and purification of oily wastewater.

4.
Langmuir ; 40(11): 5869-5877, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38437509

RESUMO

Membrane separation technology offers a sustainable and efficient solution to wastewater management; however, membrane fouling significantly impedes its application. Photocatalytic membranes, integrating photocatalytic and membrane separation technologies, enhance membrane separation efficacy while effectively mitigating organic and biological contaminations. In this work, Ag2S/PANI@PES composite membranes were prepared via a facile in situ polymerization and successive layer adsorption technique. The modified poly(ether sulfone) (PES) membrane demonstrated improved hydrophilicity and separation performance, and its heterostructure between polyaniline (PANI), Ag0, and Ag2S effectively addressed organic fouling issues. Moreover, Ag2S/PANI@PES exhibited outstanding antimicrobial properties, as well as chemical and mechanical stability.

5.
Scand J Gastroenterol ; 59(4): 445-455, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38053282

RESUMO

BACKGROUND: Accompanied by the growing prevalence of nonalcoholic fatty liver disease (NAFLD), the coexistence of chronic hepatitis B (CHB) and NAFLD has increased. In the context of CHB, there is limited understanding of the factors that influence the development of NASH. METHODS: We enrolled CHB combined NAFLD patients who had liver biopsy and divided them to NASH vs. non-NASH groups. A whole transcriptome chip was used to examine the expression profiles of long noncoding RNAs (lncRNAs) and mRNA in biopsied liver tissues. The function analysis of HIGD1A were performed. We knocked down or overexpressed HIGD1A in HepG2.2.15 cells by transient transfection of siRNA-HIGD1A or pcDNA-HIGD1A. In vivo investigations were conducted using hepatitis B virus (HBV) transgenic mice. RESULTS: In 65 patients with CHB and NAFLD, 28 were patients with NASH, and 37 were those without NASH. After screening 582 differentially expressed mRNAs, GO analysis revealed differentially expressed mRNAs acting on nicotinamide adenine dinucleotide phosphate (NADPH), which influenced redox enzyme activity. KEGG analysis also shown that they were involved in the NAFLD signaling pathway. The function analysis revealed that HIGD1A was associated with the mitochondrion. Then, both in vivo and in vitro CHB model, HIGD1A was significantly higher in the NASH group than in the non-NASH group. HIGD1A knockdown impaired mitochondrial transmembrane potential and induced cell apoptosis in HepG2.2.15 cells added oleic acid and palmitate. On the contrary, hepatic HIGD1A overexpression ameliorated free fatty acids-induced apoptosis and oxidative stress. Furthermore, HIGD1A reduced reactive oxygen species (ROS) level by increasing glutathione (GSH) expression, but Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/Acetyl-CoA carboxylase (ACC) pathway was not involved. CONCLUSION: Both in vivo and in vitro CHB model, an upward trend of HIGD1A was observed in the NASH-related inflammatory response. HIGDIA played a protective role in cells against oxidative stress. Our data suggested that HIGD1A may be a positive regulator of NASH within the CHB context.


Assuntos
Hepatite B Crônica , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatite B Crônica/complicações , Fígado/patologia , Vírus da Hepatite B/genética , Espécies Reativas de Oxigênio/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-38466071

RESUMO

Objective: To investigate glycyrrhizin's effects and molecular mechanisms on the progression of alcoholic fatty liver. Methods: An alcoholic fatty liver model was established, followed by the administration of glycyrrhizin ammonium (20 mg/kg). Liver tissue pathological changes were observed using oil red O staining, and pyroptotic bodies were observed using transmission electron microscopy. Western blot was used to detect the expression of related proteins. To establish a model of alcoholic fatty liver cells to explore the molecular mechanism of glycolic acid in this disease. Results: Glycyrrhizin ammonium reduced the area of oil red staining in liver tissue and the number of pyroptotic bodies decreased the relative protein expression of NOX2, NOX3, p-SYK, STING, p-PDE4B, NLRP3, IL-1ß, GSDMD, Caspase-1, and Caspase-4, and increased the relative protein expression of p-SHP1 and Nrf2. Conclusion: Glycyrrhizin ameliorates the progression of alcoholic fatty liver by modulating the SHP1/SYK signaling pathway in macrophages, thereby inhibiting hepatic lipid peroxidation and pyroptosis.

7.
Sensors (Basel) ; 24(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38400377

RESUMO

The construction sector is responsible for almost 30% of the world's total energy consumption, with a significant portion of this energy being used by heating, ventilation and air-conditioning (HVAC) systems to ensure people's thermal comfort. In practical applications, the conventional approach to HVAC management in buildings typically involves the manual control of temperature setpoints by facility operators. Nevertheless, the implementation of real-time alterations that are based on the thermal comfort levels of humans inside a building has the potential to dramatically improve the energy efficiency of the structure. Therefore, we propose a model for non-intrusive, dynamic inference of occupant thermal comfort based on building indoor surveillance camera data. It is based on a two-stream transformer-augmented adaptive graph convolutional network to identify people's heat-related adaptive behaviors. The transformer specifically strengthens the original adaptive graph convolution network module, resulting in further improvement to the accuracy of the detection of thermal adaptation behavior. The experiment is conducted on a dataset including 16 distinct temperature adaption behaviors. The findings indicate that the suggested strategy significantly improves the behavior recognition accuracy of the proposed model to 96.56%. The proposed model provides the possibility to realize energy savings and emission reductions in intelligent buildings and dynamic decision making in energy management systems.

8.
Sensors (Basel) ; 24(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38610494

RESUMO

Accurately and effectively detecting the growth position and contour size of apple fruits is crucial for achieving intelligent picking and yield predictions. Thus, an effective fruit edge detection algorithm is necessary. In this study, a fusion edge detection model (RED) based on a convolutional neural network and rough sets was proposed. The Faster-RCNN was used to segment multiple apple images into a single apple image for edge detection, greatly reducing the surrounding noise of the target. Moreover, the K-means clustering algorithm was used to segment the target of a single apple image for further noise reduction. Considering the influence of illumination, complex backgrounds and dense occlusions, rough set was applied to obtain the edge image of the target for the upper and lower approximation images, and the results were compared with those of relevant algorithms in this field. The experimental results showed that the RED model in this paper had high accuracy and robustness, and its detection accuracy and stability were significantly improved compared to those of traditional operators, especially under the influence of illumination and complex backgrounds. The RED model is expected to provide a promising basis for intelligent fruit picking and yield prediction.

9.
Analyst ; 148(8): 1877-1886, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36960700

RESUMO

A novel one-handed helical copoly(phenylacetylene) (CPA) bearing L-proline tripeptide pendants and a few triethoxysilyl residues was synthesized and hybridized into SiO2 porous microspheres (PMSs) during microsphere growth through the hydrolytic polycondensation of ethoxysilyl groups. Nuclear magnetic resonance and Fourier transform infrared spectroscopy results verified the successful preparation of CPA and its hybrid product using SiO2 PMSs. The chiral recognition ability of the resulting CPA with a hybridized-type chiral stationary phase (HCSP) for high-performance liquid chromatography (HPLC) was investigated, revealing its high recognition ability for selected racemates. Moreover, the HCSP showed good solvent tolerability, thus broadening the selection of suitable eluents. The separation effect of the HCSP for the racemate N,N-diphenylcyclohexane-1,2-dicarboxamide (7) improved significantly after introducing CHCl3 in the eluent, resulting in separation factors equivalent or superior to common commercially available polysaccharide-based chiral stationary phases. The proposed preparation strategy provides a new and valuable method for obtaining poly(phenylacetylene)-based HCSPs suitable for a wide range of applications and eluent conditions.

10.
Phys Chem Chem Phys ; 25(46): 31869-31873, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37970959

RESUMO

The unidirectional asymmetry transmission is demonstrated based on quasi-accidental bound states in the continuum by a one-dimensional chiral photonic crystal slab (CPhCs) composed of tilted silicon nano-pillars. The chirality breaks symmetries on the far field polarization and radiation Q-factor between the upward and downward radiation channels. Accordingly, the CPhCs only supports the unidirectional maximal asymmetry transmission at fixed incident and conical angles. The numerical simulation indicates that the CPhCs obtains a circular dichroism of 0.99 and Q-factor of 753.7 at λ = 1.565 µm. In addition, the handedness of polarization is also effectively converted between the incidence and transmission, and the handedness depends on the incident direction and conical angle. Our scheme provides a feasible route for applications in manipulating polarization and chiral sensing.

11.
Phys Chem Chem Phys ; 25(3): 2050-2055, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36546559

RESUMO

We propose a dielectric metasurface constructed by quadrumer silicon nano-disks with crossed slots in the middle. This metasurface can support the excitation of bound states in the continuum which are closely related to the toroidal dipole resonance. After introducing chiral enantiomers with weak chirality into the surrounding medium, due to the bound states in the continuum, the chiroptical effect of the metasurface can be greatly enhanced. In particular, this metasurface breaks neither the in-plane nor out-plane symmetry, which has lower requirements of spatial processing capabilities. The proposed metasurface can be used in the trace analysis of chiral enantiomers and may lead to potential applications for tailored phase control and ultra-integrated molar chiral sensing metadevices.

12.
Phys Chem Chem Phys ; 24(46): 28325-28332, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36383206

RESUMO

The propagating behavior of surface plasmons in chiral media is different from that in achiral media. By comparing the propagation behavior of SPPs, the chirality of the environment can be evaluated. We theoretically reveal the features of SPPs in a structure with two individual graphene sheets surrounded by chiral environment. A more universal dispersion relation covering the achiral cases is obtained. The effects of the chirality of medium and the chemical potential of graphene on the SPPs are explored. Besides, a novel method of detecting the chirality of the environment based on the lateral optical force and torque is proposed. The characteristics of the structure may enrich the surface plasmonic wave theory on the waveguides with multiple graphene sheets and provide new opportunities for the design of more compact nanophotonic functional devices and novel biosensors.

13.
Chirality ; 34(5): 701-710, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35174536

RESUMO

A novel cellulose derivative bearing bulky 4-(2-benzothienyl)phenylcarbamate substituents (Cel-1) was readily synthesized by carbamoylation followed by Suzuki-Miyaura coupling reaction. The corresponding coated-type chiral stationary phase (CSP) was prepared on basis of the derivative, and its chiral recognition ability was then evaluated by high-performance liquid chromatography (HPLC). The chiral recognition ability of the cellulose derivative was greatly influenced by introduction of the bulky benzothienyl pendants on the aromatic moieties of phenylcarbamates, compared with its analog with smaller groups. Many racemates, including the metal tris(acetylacetonate) complexes, chiral drug, and the analyte with axial chirality, were sufficiently separated with good enantioselectivities on Cel-1. Some of them were even higher than those on the commercially powerful Chiralcel OD, which is also a coated-type CSP derived from cellulose phenylcarbamate derivative containing smaller 3,5-dimethyl pendants. The 1 H NMR and circular dichroism (CD) spectra of Cel-1 indicated that the obtained derivative possessed a regular higher order structure, and a strong cotton effect was observed within the absorption range of π-conjugated pendant at 350-500 nm. Impressively, the cellulose derivative bearing the bulky 4-(2-benzothienyl)phenylcarbamates exhibited good enantioselective fluorescence quenching behavior to the enantiomer pair of 1-phenylethylamine, probably suggesting its potential for the application as a chiral fluorescent sensor with high efficiency. The combination of the arrangement of bulky π-conjugated benzothienyl pendants on the phenylcarbamate moieties surrounding the helical backbone and the regular higher order structure of the polymer itself probably played a key role for this high chiral fluorescent recognition ability of Cel-1. The interaction sites of bulky 4-(2-benzothienyl)phenylcarbamate pendants in its excited state can exhibit higher enantioselective discrimination via fluorescent response to the chiral compound Q1, whereas the chiral recognition ability of Cel-1 to the same compound in the ground state had no clear improvement.


Assuntos
Celulose , Fenilcarbamatos , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Dicroísmo Circular , Fenilcarbamatos/química , Estereoisomerismo
14.
Eur Child Adolesc Psychiatry ; 31(1): 99-120, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33185773

RESUMO

It is known that younger patients treated with antipsychotics are at increased risk of metabolic events; however, it is unknown how this risk varies according to ethnicity, the class of antipsychotic and the specific product used, and by age group. We conducted a multinational sequence symmetry study in Asian populations (Hong Kong, Japan, Korea, Taiwan and Thailand) and non-Asian populations (Australia and Denmark) to evaluate the metabolic events associated with antipsychotics in both Asian and non-Asian populations, for typical and atypical antipsychotics, and by the subgroups of children and adolescents, and young adults. Patients aged 6-30 years newly initiating oral antipsychotic drugs were included. We defined a composite outcome for metabolic events which included dyslipidemia, hypertension and hyperglycemia. We calculated the sequence ratio (SR) by dividing the number of people for whom a medicine for one of the outcome events was initiated within a 12-month period after antipsychotic initiation by the number before antipsychotic initiation. This study included 346,904 antipsychotic initiators across seven countries. Antipsychotic use was associated with an increased risk of composite metabolic events with a pooled adjusted SR (ASR) of 1.22 (95% CI 1.00-1.50). Pooled ASRs were similar between Asian (ASR, 1.22; 95% CI 0.88-1.70) and non-Asian populations (ASR, 1.22; 95% CI 1.04-1.43). The pooled ASR for typical and atypical antipsychotics was 0.98 (95% CI 0.85-1.12) and 1.24 (95% CI 0.97-1.59), respectively. No difference was observed in the relative effect in children and adolescents compared to young adults. The risk of metabolic events associated with antipsychotics use was similar in magnitude in Asian and non-Asian populations despite the marked difference in drug utilization patterns.


Assuntos
Antipsicóticos , Adolescente , Adulto , Antipsicóticos/efeitos adversos , Austrália , Criança , Etnicidade , Humanos , República da Coreia , Taiwan , Adulto Jovem
15.
Cluster Comput ; 25(5): 3591-3616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431616

RESUMO

Surgical case scheduling is a key issue in the field of medician, which is a challenging work because of the difficulty in assigning resources to patients. This study regards the surgical case scheduling problem as a flexible job shop scheduling problem (FJSP). Considering the switching and preparation time of patients in different stage, an improved multi-objective imperialist competitive algorithm (IMOICA), which adopts the non-dominant sorting method, is proposed to optimize the whole scheduling. First, the social hierarchy strategy is developed to initialize the empire. Then, to enhance the global search ability of the algorithm, the concept of attraction and repulsion (AR) is introduced into the assimilation strategy. Moreover, to increase the diversity of the population, the revolution strategy is utilized. Finally, the variable neighborhood search (VNS) strategy is embedded to improve its exploitation capacity further. Experiments show that scheduling in advance saves time and cost, and IMOICA can solve the surgical case scheduling problem studied efficiently.

16.
Opt Lett ; 46(8): 1975-1978, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33857120

RESUMO

In this Letter, considering the chiral-graphene-chiral structure, we investigate the more universal dispersion relation covering the achiral cases, the effect of the chirality of a medium, and the chemical potential of graphene on the behavior of graphene surface plasmon polaritons (GSPPs) and transverse spin density, which is key to understanding the lateral optical force. This research is dedicated to looking for a regulating mechanism based on chirality and graphene to apply in devices of information processing and biosensor for identifying molecular chirality. We found the averaging effect of chirality in both sides of graphene in tuning the behavior of GSPPs. We believe this work can make contributions to enrich SPP theory and benefit the development of novel detection techniques for chiral molecules based on graphene.

17.
Appl Intell (Dordr) ; 51(6): 3936-3951, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34764571

RESUMO

The outbreak of the novel coronavirus clearly highlights the importance of the need of effective physical examination scheduling. As treatment times for patients are uncertain, this remains a strongly NP-hard problem. Therefore, we introduce a complex flexible job shop scheduling model. In the process of physical examination for suspected patients, the physical examiner is considered a job, and the physical examination item and equipment correspond to an operation and a machine, respectively. We incorporate the processing time of the patient during the physical examination, the transportation time between equipment, and the setup time of the patient. A unique scheduling algorithm, called imperialist competition algorithm with global search strategy (ICA_GS) is developed for solving the physical examination scheduling problem. A local search strategy is embedded into ICA_GS for enhancing the searching behaviors, and a global search strategy is investigated to prevent falling into local optimality. Finally, the proposed algorithm is tested by simulating the execution of the physical examination scheduling processes, which verify that the proposed algorithm can better solve the physical examination scheduling problem.

19.
Opt Lett ; 45(10): 2826-2829, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32412478

RESUMO

Magnetic and electric toroidal dipoles possess interesting properties differing from traditional electric and magnetic dipoles. In order to generate both the magnetic and electric toroidal dipoles simultaneously in one single structure, a permittivity-asymmetric dielectric metasurface is proposed, which is composed of clusters of four high-index dielectric nano-disks with asymmetric permittivity distribution. These two types of toroidal dipole responses can be separately observed at different spectral positions. This study reveals that symmetry-breaking in a broad sense is crucial for exciting toroidal responses, and the proposed metasurface points to a unique routine of exciting and enhancing the toroidal responses, which may be used to realize efficient light-matter interaction in the area of meta-optics.

20.
Langmuir ; 36(3): 760-768, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31893498

RESUMO

Intelligent materials with controlled wettability have caused widespread concern in various sewage applications. In this study, a smart pH-responsive polyaniline (PANI) coating has been synthesized in one step in aqueous media and coated on materials in common use, such as polyester mesh, cotton fabric, and sponge. The PANI coatings can switch their superwettability response to ambient pH and be used in continuous separation of oil-water-oil systems which are frequently found in actual oil leakage accidents. Moreover, bidirectional emulsion separation (water-in-oil and oil-in-water) can be realized on such a coating material. The coated sponge can be used as an oil adsorbent for invertible capture and release by changing pH. Based on excellent antifouling and recyclability, as well as the prominent chemical/mechanical stability, PANI coatings can be applied in actual oily wastewater treatment systems. It is anticipated that the coating materials will show promise in many applications because of the cost-effective and environmentally friendly aqueous media preparation procedure.

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