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1.
Anal Chem ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38730304

ABSTRACT

Rapidly identifying and quantifying Gram-positive bacteria are crucial to diagnosing and treating bacterial lower respiratory tract infections (LRTIs). This work presents a field-deployable biosensor for detecting Gram-positive bacteria from exhaled breath condensates (EBCs) based on peptidoglycan recognition using an aptamer. Dielectrophoretic force is employed to enrich the bacteria in 10 s without additional equipment or steps. Concurrently, the measurement of the sensor's interfacial capacitance is coupled to quantify the bacteria during the enrichment process. By incorporation of a semiconductor condenser, the whole detection process, including EBC collection, takes about 3 min. This biosensor has a detection limit of 10 CFU/mL, a linear range of up to 105 CFU/mL and a selectivity of 1479:1. It is cost-effective and disposable due to its low cost. The sensor provides a nonstaining, culture-free and PCR-independent solution for noninvasive and real-time diagnosis of Gram-positive bacterial LRTIs.

2.
Opt Express ; 32(7): 11886-11894, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38571026

ABSTRACT

A polarization beam-splitting multimode filter using pixelated waveguides has been presented and experimentally demonstrated in this paper. Finite difference time domain method and direct binary search optimization algorithm are employed to optimize pixelated waveguides to realize compact size, broad bandwidth, large extinction ratio, low insertion loss, and good polarization extinction ratio. Measurement results show that, in a wavelength range from 1520 to 1560 nm, for the fabricated device working at transverse-electric polarization, the measured insertion loss is less than 1.23 dB and extinction ratio is larger than 15.14 dB, while for transverse-magnetic polarization, the corresponding insertion loss lower than 0.74 dB and extinction ratio greater than 15.50 dB are realized. The measured polarization extinction ratio larger than 15.02 dB is achieved. The device's length is only 15.4 µm.

3.
J Biochem Mol Toxicol ; 38(5): e23714, 2024 May.
Article in English | MEDLINE | ID: mdl-38629493

ABSTRACT

Parkinson's disease (PD) is a neurodegenerative disease featured by progressive loss of nigrostriatal dopaminergic neurons, the etiology of which is associated with the existence of neuroinflammatory response and oxidative stress. Vincamine is an indole alkaloid that was reported to exhibit potent anti-inflammatory and antioxidant properties in many central and/or peripheral diseases. Nevertheless, the specific role of vincamine in PD development remains unknown. In our study, dopaminergic neuron loss was determined through immunohistochemistry staining and western blot analysis of tyrosine hydroxylase (TH) expression in the substantia nigra (SN) of PD mice. Reactive oxygen species (ROS) production and malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) levels were detected through DHE staining and commercially available kits to assess oxidative stress. Pro-inflammatory cytokine (TNF-α, IL-1ß, and IL-6) levels in the SN were measured via RT-qPCR and western blot analysis. Microglial and astrocyte activation was examined through immunofluorescence staining of Iba-1 (microglia marker) and GFAP (astrocyte marker) in the SN. The regulation of vincamine on the NF-κB and Nrf2/HO-1 pathway was estimated through western blot analysis. Our results showed that vincamine treatment decreased TNF-α, IL-1ß, and IL-6 mRNA and protein levels, reduced GFAP and Iba-1 expression, decreased ROS production and MDA level, and increased SOD activity and GSH level in the SN of PD mice. Mechanically, vincamine repressed the phosphorylation levels of p65, IKKß, and IκBα but enhanced the protein levels of Nrf2 and HO-1 in PD mice. Collectively, vincamine plays a neuroprotective role in PD mouse models by alleviating neuroinflammation and oxidative damage via suppressing the NF-κB pathway and activating the Nrf2/HO-1 pathway.


Subject(s)
Parkinson Disease , Vincamine , Animals , Mice , Brain Injuries , Interleukin-6/metabolism , Neurodegenerative Diseases , Neuroinflammatory Diseases , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Oxidative Stress , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , Reactive Oxygen Species , Signal Transduction , Superoxide Dismutase/metabolism , Tumor Necrosis Factor-alpha/metabolism , Vincamine/administration & dosage
4.
Front Immunol ; 15: 1322256, 2024.
Article in English | MEDLINE | ID: mdl-38524127

ABSTRACT

Introduction: Wound healing poses a clinical challenge in diabetes mellitus (DM) due to compromised host immunity. CD64, an IgG-binding Fcgr1 receptor, acts as a pro-inflammatory mediator. While its presence has been identified in various inflammatory diseases, its specific role in wound healing, especially in DM, remains unclear. Objectives: We aimed to investigate the involvement of CD64 in diabetic wound healing using a DM animal model with CD64 KO mice. Methods: First, we compared CD64 expression in chronic skin ulcers from human DM and non-DM skin. Then, we monitored wound healing in a DM mouse model over 10 days, with or without CD64 KO, using macroscopic and microscopic observations, as well as immunohistochemistry. Results: CD64 expression was significantly upregulated (1.25-fold) in chronic ulcerative skin from DM patients compared to non-DM individuals. Clinical observations were consistent with animal model findings, showing a significant delay in wound healing, particularly by day 7, in CD64 KO mice compared to WT mice. Additionally, infiltrating CD163+ M2 macrophages in the wounds of DM mice decreased significantly compared to non-DM mice over time. Delayed wound healing in DM CD64 KO mice correlated with the presence of inflammatory mediators. Conclusion: CD64 seems to play a crucial role in wound healing, especially in DM conditions, where it is associated with CD163+ M2 macrophage infiltration. These data suggest that CD64 relies on host immunity during the wound healing process. Such data may provide useful information for both basic scientists and clinicians to deal with diabetic chronic wound healing.


Subject(s)
Diabetes Mellitus, Experimental , Skin Ulcer , Wound Healing , Animals , Mice , Diabetes Mellitus, Experimental/metabolism , Disease Models, Animal , Macrophages/metabolism , Skin/metabolism , Wound Healing/genetics
5.
Int Wound J ; 21(4): e14562, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38130102

ABSTRACT

Burn injuries result in localised tissue damage and precipitate systemic responses; routine clinical treatments, which typically include metabolic nutritional support and anti-infection therapies, do not yield optimal outcomes. Therefore, we aimed to systematically evaluate the effects of ulinastatin on wound infection and healing in patients with burns to provide reliable evidence-based recommendations for burn treatment. An electronic search of the Web of Science, PubMed, Cochrane Library, Embase, Wanfang, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure databases, supplemented by manual searches, was conducted from database inception to October 2023 to collect randomised controlled trials (RCTs) assessing the efficacy of ulinastatin for the treatment of burns. Two researchers screened all retrieved articles according to the inclusion and exclusion criteria; the included studies were evaluated for quality, and the relevant data were extracted. Stata 17.0 software was employed for data analysis. Overall, 8 RCTs with 803 patients were included, with 404 and 399 in the ulinastatin and conventional treatment groups, respectively. The analysis revealed that wound infections (odds ratio [OR] = 0.08, 95% CI: 0.02-0.35, p = 0.001) and complications (OR = 0.21, 95% CI: 0.10-0.42, p < 0.001) were significantly lower, and wound healing time (standardised mean differences [SMD] = -1.31, 95% CI: -2.05 to -0.57, p = 0.001) was significantly shorter, in the ulinastatin groups than in the control group. This meta-analysis revealed that ulinastatin can effectively reduce the incidence of wound infections and complications and significantly shorten the duration of wound healing in patients with burns, thereby promoting early recovery in these patients.


Subject(s)
Burns , Glycoproteins , Wound Infection , Humans , Wound Infection/drug therapy , Wound Healing , Burns/complications , Burns/drug therapy , China
6.
Micromachines (Basel) ; 14(11)2023 Oct 29.
Article in English | MEDLINE | ID: mdl-38004870

ABSTRACT

Bridge sensors are widely used in military and civilian fields, and their demand gradually increases each year. Digital sensors are widely used in the military and civilian fields. High-precision and low-power analog-to-digital converters (ADCs) as sensor read-out circuits are a research hotspot. Sigma-delta ADC circuits based on switched-capacitor topology have the advantages of high signal-to-noise ratio (SNR), good linearity, and better compatibility with CMOS processes. In this work, a fourth-order feed-forward sigma-delta modulator and a digital decimation filter are designed and implemented with a correlated double sampling technique (CDS) to suppress pre-integrator low-frequency noise. This work used an active pre-compensator circuit for deep phase compensation to improve the system's stability in the sigma-delta modulator. The modulator's local feedback factor is designed to be adjustable off-chip to eliminate the effect of process errors. A three-stage cascade structure was chosen for the post-stage digital filter, significantly reducing the number of operations and the required memory cells in the digital circuit. Finally, the layout design and engineering circuit were fabricated by a standard 0.35 µm CMOS process from Shanghai Hua Hong with a chip area of 9 mm2. At a 5 V voltage supply and sampling frequency of 6.144 MHz, the modulator power consumption is 13 mW, the maximum input signal amplitude is -3 dBFs, the 1 Hz dynamic range is about 118 dB, the modulator signal-to-noise ratio can reach 110.5 dB when the signal bandwidth is 24 kHz, the practical bit is about 18.05 bits, and the harmonic distortion is about -113 dB, which meets the design requirements. The output bit stream is 24 bits.

7.
Arterioscler Thromb Vasc Biol ; 43(12): 2301-2311, 2023 12.
Article in English | MEDLINE | ID: mdl-37855127

ABSTRACT

BACKGROUND: The regional heterogeneity of vascular components and transcriptomes is an important determinant of aortic biology. This notion has been explored in multiple mouse studies. In the present study, we examined the regional heterogeneity of aortas in nonhuman primates. METHODS: Aortic samples were harvested from the ascending, descending thoracic, suprarenal, and infrarenal regions of young control monkeys and adult monkeys with high fructose consumption for 3 years. The regional heterogeneity of aortic structure and transcriptomes was examined by histological and bulk RNA sequencing analyses, respectively. RESULTS: Immunostaining of CD31 and αSMA (alpha-smooth muscle actin) revealed that endothelial and smooth muscle cells were distributed homogeneously across the aortic regions. In contrast, elastic fibers were less abundant and dispersed in the infrarenal aorta compared with other regions and associated with collagen deposition. Bulk RNA sequencing identified a distinct transcriptome related to the Notch signaling pathway in the infrarenal aorta with significantly increased NOTCH3 mRNA compared with other regions. Immunostaining revealed that NOTCH3 protein was increased in the media of the infrarenal aorta. The abundance of medial NOTCH3 was positively correlated with the dispersion of elastic fibers. Adult cynomolgus monkeys with high fructose consumption displayed vascular wall remodeling, such as smooth muscle cell loss and elastic fiber disruption, predominantly in the infrarenal region. The correlation between NOTCH3 and elastic fiber dispersion was enhanced in these monkeys. CONCLUSIONS: Aortas of young cynomolgus monkeys display regional heterogeneity of their transcriptome and the structure of elastin and collagens. Elastic fibers in the infrarenal aorta are dispersed along with upregulation of medial NOTCH3.


Subject(s)
Aorta, Abdominal , Elastic Tissue , Animals , Mice , Aorta, Abdominal/metabolism , Macaca fascicularis/metabolism , Elastic Tissue/metabolism , Receptor, Notch3/genetics , Receptor, Notch3/metabolism , Elastin/metabolism , Collagen/metabolism , Fructose
8.
Environ Sci Pollut Res Int ; 30(52): 112104-112116, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37824054

ABSTRACT

Aerobic composting, especially semipermeable membrane-covered aerobic fermentation, is known to be an effective method for recycling and reducing vegetable waste. However, this approach has rarely been applied to the aerobic composting of vegetable waste; in addition, the product characteristics and GHG emissions of the composting process have not been studied in-depth. This study investigated the effect of using different structural ventilation systems on composting efficiency and greenhouse gas emissions in a semipermeable membrane-covered vegetable waste compost. The results for the groups (MV1, MV2, and MV3) with bottom ventilation plus multichannel ventilation and the group (BV) with single bottom ventilation were compared here. The MV2 group effectively increased the average temperature by 19.06% whilst also increasing the degradation rate of organic matter by 30.81%. Additionally, the germination index value reached more than 80%, 3 days in advance. Compared to those of the BV group, the CH4, N2O, and NH3 emissions of MV2 were reduced by 32.67%, 21.52%, and 22.57%, respectively, with the total greenhouse gas emissions decreasing by 24.17%. Overall, this study demonstrated a multichannel ventilation system as a new method for improving the composting efficiency of vegetable waste whilst reducing gas emissions.


Subject(s)
Composting , Greenhouse Gases , Composting/methods , Greenhouse Gases/analysis , Vegetables , Methane/analysis , Temperature , Soil/chemistry
9.
bioRxiv ; 2023 Aug 26.
Article in English | MEDLINE | ID: mdl-37767086

ABSTRACT

Background: The regional heterogeneity of vascular components and transcriptomes is an important determinant of aortic biology. This notion has been explored in multiple mouse studies. In the present study, we examined the regional heterogeneity of aortas in non-human primates. Methods: Aortic samples were harvested from the ascending, descending, suprarenal, and infrarenal regions of young control monkeys and adult monkeys provided with high fructose for 3 years. The regional heterogeneity of aortic structure and transcriptomes was examined by histological and bulk RNA sequencing analyses. Results: Immunostaining of CD31 and αSMA revealed that endothelial and smooth muscle cells were distributed homogeneously across the aortic regions. In contrast, elastic fibers were less abundant and dispersed in the infrarenal aorta compared to other regions and associated with collagen deposition. Bulk RNA sequencing identified a distinct transcriptome related to the Notch signaling pathway in the infrarenal aorta with significantly increased NOTCH3 mRNA compared to other regions. Immunostaining revealed that NOTCH3 protein was increased in the media of the infrarenal aorta. The abundance of medial NOTCH3 was positively correlated with the dispersion of elastic fibers. Adult cynomolgus monkeys provided with high fructose displayed vascular wall remodeling, such as smooth muscle cell loss and elastic fiber disruption, predominantly in the infrarenal region. The correlation between NOTCH3 and elastic fiber dispersion was enhanced in these monkeys. Conclusions: Aortas of young cynomolgus monkeys display regional heterogeneity of their transcriptome and the structure of elastin and collagens. Elastic fibers in the infrarenal aorta are dispersed along with upregulation of medial NOTCH3. HIGHLIGHTS: - The present study determined the regional heterogeneity of aortas from cynomolgus monkeys.- Aortas of young cynomolgus monkeys displayed region-specific aortic structure and transcriptomes.- Elastic fibers were dispersed in the infrarenal aorta along with increased NOTCH3 abundance in the media.

10.
Environ Sci Pollut Res Int ; 30(44): 99620-99651, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37620698

ABSTRACT

Nowadays, solar power generation has gradually become a part of electric energy sharing. How to effectively enhance the energy conversion efficiency of solar cells and components has gradually emerged as a focal point of research. This paper presents a boosted atomic search optimization (ASO) with a new anti-sine-cosine mechanism (ASCASO) to realize the parameter estimation of photovoltaic (PV) models. The anti-sine-cosine mechanism is inspired by the update principle of sine cosine algorithm (SCA) and the mutation strategy of linear population size reduction adaptive differential evolution (LSHADE). The working principle of anti-sine-cosine mechanism is to utilize two mutation formulas containing arcsine and arccosine functions to further update the position of atoms. The introduction of anti-sine-cosine mechanism achieves the populations' random handover and promotes the neighbors' information communication. For better evaluation, the proposed ASCASO is devoted to estimate parameters of three PV models of R.T.C France, one Photowat-PWP201 PV module model, and two commercial polycrystalline PV panels including STM6-40/36 and STM6-120/36 with monocrystalline cells. The proposed ASCASO is compared with nine reported comparative algorithms to assess the performance. The results of parameter estimation for different PV models of various methods demonstrate that ASCASO performs more accurately and reliably than other reported comparative methods. Thus, ASCASO can be considered a highly effective approach for accurately estimating the parameters of PV models.


Subject(s)
Algorithms , Communication , Electricity , France , Mutation
11.
Materials (Basel) ; 16(15)2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37569962

ABSTRACT

Composite structure design is an important way to improve reinforcement strengthening efficiency. The dispersion of the external reinforcement is often not uniform enough, however, and it is agglomerated in the matrix, which cannot uniformly and effectively bear the load. The interconnected reinforcement network prepared by the in-situ self-growth method is expected to obtain higher material properties. In this paper, the TiN shell was formed on the surface of Ti powder by the in-situ nitriding method, and then the network TiN/Ti composites were prepared by sintering. In the control group, TiN was dispersed by mechanical ball milling, and it was found that TiN powder was coated on the surface of Ti particles, and the sintered TiN/Ti composites formed a discontinuous structure with a great deal of TiN agglomeration. A uniform TiN nitride layer of 5~7 µm was formed on the surface of Ti powder by the in-situ nitriding method, and a connected TiN network was formed in the sintered Ti-N/Ti composites. The composites prepared by nitriding have higher compressive strength, hardness, and plasticity. The hardness of the Ti-N/Ti composite is 685.7 HV and the compressive strength is 1468.5 MPa. On this basis, the influence of the connected TiN structure on the material properties was analyzed, which provided theoretical guidance for the structural design of the network structure-reinforced titanium matrix composites.

12.
Front Neurosci ; 17: 1146147, 2023.
Article in English | MEDLINE | ID: mdl-37434761

ABSTRACT

Astrocytes are highly heterogeneous and involved in different aspects of fundamental functions in the central nervous system (CNS). However, whether and how this heterogeneous population of cells reacts to the pathophysiological challenge is not well understood. To investigate the response status of astrocytes in the medial vestibular nucleus (MVN) after vestibular loss, we examined the subtypes of astrocytes in MVN using single-cell sequencing technology in a unilateral labyrinthectomy mouse model. We discovered four subtypes of astrocytes in the MVN with each displaying unique gene expression profiles. After unilateral labyrinthectomy, the proportion of the astrocytic subtypes and their transcriptional features on the ipsilateral side of the MVN differ significantly from those on the contralateral side. With new markers to detect and classify the subtypes of astrocytes in the MVN, our findings implicate potential roles of the adaptive changes of astrocyte subtypes in the early vestibular compensation following peripheral vestibular damage to reverse behavioral deficits.

13.
Opt Lett ; 48(12): 3347-3350, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37319098

ABSTRACT

In this Letter, a polarization-insensitive high-order mode pass filter is presented, designed, and experimentally demonstrated. When TE0, TM0, TE1, and TM1 modes are injected into the input port, TM0 and TE0 modes are filtered, and TE1 and TM1 modes exit from the output port. To attain compactness, broad bandwidth, low insertion loss, excellent extinction ratio, and polarization-insensitive property, the finite difference time domain method and direct-binary-search or particle swarm optimization algorithm are employed for the optimization of structural parameters of the photonic crystal region and the coupling region in the tapered coupler. Measurement results reveal that, for the fabricated filter working at TE polarization, the extinction ratio and insertion loss are 20.42 and 0.32 dB at 1550 nm. In the case of TM polarization, the corresponding extinction ratio and insertion loss are 21.43 and 0.30 dB. Within a bandwidth from 1520 to 1590 nm, insertion loss smaller than 0.86 dB and extinction ratio larger than 16.80 dB are obtained for the fabricated filter working at TE polarization, while in the case of TM polarization, insertion loss lower than 0.79 dB and extinction ratio greater than 17.50 dB are realized.


Subject(s)
Algorithms , Photons
14.
Plant Dis ; 2023 Jun 29.
Article in English | MEDLINE | ID: mdl-37386701

ABSTRACT

Bletilla striata (Thunb. ex Murray) Rchb. F. (Orchidaceae) is an endangered traditional Chinese medicinal plant and has been traditionally used for hemostasis and detumescence in China (Wang et al. 2022). In March of 2021, during a field survey in Xuanwei city, Yunnan province, China, some B. striata plants with symptoms of plant dwarfing and leaf yellowing were observed. Roots of diseased plants presented numerous galls, typical symptoms of root-knot nematodes (RKNs) infection. The diseased area was approximately 66667 m2, showing a patchy disease distribution pattern. To identify the species of RKNs, females and eggs were isolated from galled tissue, and second-stage juveniles (J2s) were collected from eggs hatched. Nematodes were identified through comprehensive morphological and molecular methods. The perineal pattern of females is round to ovoid with a flat or moderately high dorsal arch and has two conspicuous lateral line striae. Morphological measurements of females (n=20) included body length (L) = 702.9 ± 70.8 (556.2-780.2) µm, body width (BW) = 404.1 ± 48.5 (327.5-470.1) µm, stylet length = 15.5 ± 2.2 (12.3-18.6) µm, distance from base of stylet to dorsal esophageal gland opening (DGO) = 3.7 ± 0.8 (2.1-4.9) µm. The morphometrics of J2s (n=20), L = 438.4 ± 22.6 (354.1-464.8) µm, BW = 17.4 ± 2.0 (12.9-20.8) µm, stylet length = 13.5 ± 0.4 (13.0-14.2) µm, DGO = 3.2 ± 0.6 (2.6-4.7) µm, and hyaline tail terminus = 12.3 ± 1.9 (9.6-15.7) µm. These morphological characteristics were similar to the original descriptions of Meloidogyne javanica (Rammah and Hirschmann 1990). DNA extraction was done 60 times, each from a different single females following the method of Yang et al. (2020). Amplification of ITS1-5.8S-ITS2 region of rDNA and the coxI region of mtDNA was done by using primers 18S/26S (5'-TTGATTACGTCCCTGCCCTTT-3'/5'-TTTCACTCGCCGTTACTAAGG-3') (Vrain et al. 1992) and cox1F/cox1R (5'-TGGTCATCCTGAAGTTTATG-3'/5'-CTACAACATAATAAGTATCATG-3') (Trinh et al. 2019) respectively. The PCR amplification program followed the method described by Yang et al. (2021). The ITS1-5.8S-ITS2 gene sequence (768 bp, GenBank Accession No. OQ091922) showed 99.35-100% identical to the known sequences of M. javanica (GenBank Accession Nos. KX646187, MW672262, KJ739710, KP901063, MK390613). The coxI gene sequence (410 bp, OQ080070) showed 99.75%-100% identical to the known sequences of M. javanica (OP646645, MZ542457, KP202352, KU372169, KU372170). Furthermore, M. javanica species-specific primers Fjav/Rjav (5'-GGTGCGCGATTGAACTGAGC-3'/5'-CAGGCCCTTCAGTGGAACTATAC-3') were used for PCR amplification. An expected fragment of approximately 670 bp was obtained, which was identical to that previously reported for M. javanica (Zijlstra et al. 2000). To verify pathogenicity of this nematode on B. striata, six 1.6-year-old tissue culture seedings of B. striata were maintained in 10-cm-diameter × 9-cm-high plastic pots containing a sterilized mixed soil (humus soil: laterite soil: perlite=3:1:1), and each plant was inoculated with 1000 J2s hatched from eggs of M. javanica. Three non-inoculated B. striata were used as the negative controls. All plants were placed in a greenhouse at approximately 14~26 ℃. After 90 days, the inoculated plants presented symptoms of leaf yellowing, and the roots with root knots identical to those observed in the fields. The root gall rating was 2 according to the 0-5 RKNs rating scale (Anwar and McKenry, 2002) and the reproductive factor (RF= final population/initial population) was 1.6. No symptoms or nematodes were observed on control plants. The nematode was reisolated and identified as M. javanica by morphological and molecular methods as above. To our knowledge, this is the first report of infection of M. javanica on B. striata. The infection of this economically important medicinal plant with M. javanica could pose a great threat to B. striata production in China, and further research will be necessary to develop control strategies.

15.
Front Public Health ; 11: 1093264, 2023.
Article in English | MEDLINE | ID: mdl-37033036

ABSTRACT

Introduction: China has the largest youth population in the world. To better implement the Smoke-free School Initiative, this study aims to examine the protective and risk factors for different smoking behaviors (never smoked, experimental smoking, and current smoking) among school adolescents based on social cognitive theory. Methods: This research was a secondary analysis of a cross-sectional survey of middle schools in Huli District of Xiamen, China. The final sample consisted of 1937 participants with an average age of 15.41 (SD = 1.64). Descriptive statistics were used to summarize the sociodemographic characteristics of the sample. Multivariate multinomial logistic regression analysis was performed using four models. Results: Of the respondents, 1685 (86.99%) were never smokers, 210 (10.84%) were experimental smokers, and 42 (2.17%) were current smokers. Social norms, positive outcome expectations, anti-smoking self-efficacy, and attitudes toward control tobacco policies were associated with adolescents' smoking behaviors. The number of smoking family members, classmates smoking, the perception that smoking is cool and attractive, and attitudes toward control tobacco policies were the predictors of current smoking behavior (p < 0.05). In contrast, friends smoking and individual and social relationship motivation were associated with only experimental smoking (p < 0.05). Discussion: The relationship of social norms, positive outcome expectations, anti-smoking self-efficacy, and attitudes toward control tobacco policies varied across smoking behaviors. Family, school, society and the government need to cooperate in prevention and intervention programs for adolescent smoking. The relationships between these factors and adolescents' different smoking behaviors needs to be further verified.


Subject(s)
Attitude , Family , Humans , Adolescent , Cross-Sectional Studies , Smoking/epidemiology , Cognition
16.
Opt Express ; 31(5): 8375-8383, 2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36859952

ABSTRACT

The integrated optical isolator is an essential building block in photonic integrated chips. However, the performance of on-chip isolators based on the magneto-optic (MO) effect has been limited due to the magnetization requirement of permanent magnets or metal microstrips on MO materials. Here, an MZI optical isolator built on a silicon-on-insulator (SOI) without any external magnetic field is proposed. A multi-loop graphene microstrip operating as an integrated electromagnet above the waveguide, instead of the traditional metal microstrip, generates the saturated magnetic fields required for the nonreciprocal effect. Subsequently, the optical transmission can be tuned by varying the intensity of currents applied on the graphene microstrip. Compared with gold microstrip, the power consumption is reduced by 70.8%, and temperature fluctuation is reduced by 69.5% while preserving the isolation ratio of 29.44 dB and the insertion loss of 2.99 dB at1550 nm.

17.
Micromachines (Basel) ; 14(2)2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36838145

ABSTRACT

Three-input logic primitives show high efficiency in logic synthesis compared to traditional two-input logic, which encourages researchers to implement three-input logic gates with emerging nanotechnologies. This paper demonstrates a compact implementation of three-input monotone logic gates based on the inverted T-shaped TFET. Firstly, based on the gate coupling mechanism in the novel inverted T channel, the BTBT current can be suppressed in the vertical or horizontal region to achieve the channel strobe. Therefore, the typical three-input monotone logic functions, Majority, OrAnd, and AndOr, are successfully implemented on a single transistor. Then, a simplified potential model describing gate coupling is established to describe the impact of key device parameters on the logic behavior. Combined with TCAD simulation, the design rules of devices with different logic functions are given. Finally, a series of three-input monotonic logic gates are designed and verified. The results show that the use of the proposed TFETs can effectively save the number of transistors in the three-input logic gate, which indicates that the three-input TFET is a compact and flexible candidate for three-input logic gates.

18.
Materials (Basel) ; 16(3)2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36770172

ABSTRACT

Composite material uses ceramic reinforcement to add to the metal matrix to obtain higher material properties. Structural design is an important direction of composite research. The reinforcement distribution of the core-shell structure has the unique advantages of strong continuity and uniform stress distribution. In this paper, a method of preparing boron carbide (B4C)-coated titanium (Ti) powder particles by ball milling and preparing core-shell B4C-reinforced Ti matrix composites by Spark Plasma Sintering was proposed. It can be seen that B4C coated on the surface of the spherical Ti powder to form a shell structure, and B4C had a certain continuity. Through X-ray diffraction characterization, it was found that B4C reacted with Ti to form layered phases of titanium boride (TiB) and titanium carbide (TiC). The compressive strength of the composite reached 1529.1 MPa, while maintaining a compressive strain rate of 5%. At the same time, conductivity and thermal conductivity were also characterized. The preparation process of the core-shell structure composites proposed in this paper has high feasibility and universality, and it is expected to be applied to other ceramic reinforcements. This result provides a reference for the design, preparation and performance research of core-shell composite materials.

19.
Nature ; 615(7951): 231-236, 2023 03.
Article in English | MEDLINE | ID: mdl-36813971

ABSTRACT

Observation of strong correlations and superconductivity in twisted-bilayer graphene1-4 has stimulated tremendous interest in fundamental and applied physics5-8. In this system, the superposition of two twisted honeycomb lattices, generating a moiré pattern, is the key to the observed flat electronic bands, slow electron velocity and large density of states9-12. Extension of the twisted-bilayer system to new configurations is highly desired, which can provide exciting prospects to investigate twistronics beyond bilayer graphene. Here we demonstrate a quantum simulation of superfluid to Mott insulator transition in twisted-bilayer square lattices based on atomic Bose-Einstein condensates loaded into spin-dependent optical lattices. The lattices are made of two sets of laser beams that independently address atoms in different spin states, which form the synthetic dimension accommodating the two layers. The interlayer coupling is highly controllable by a microwave field, which enables the occurrence of a lowest flat band and new correlated phases in the strong coupling limit. We directly observe the spatial moiré pattern and the momentum diffraction, which confirm the presence of two forms of superfluid and a modified superfluid to insulator transition in twisted-bilayer lattices. Our scheme is generic and can be applied to different lattice geometries and for both boson and fermion systems. This opens up a new direction for exploring moiré physics in ultracold atoms with highly controllable optical lattices.

20.
Comput Biol Med ; 155: 106623, 2023 03.
Article in English | MEDLINE | ID: mdl-36809696

ABSTRACT

In this article, we propose a lightweight and competitively accurate heart rhythm abnormality classification model based on classical convolutional neural networks in deep neural networks and hardware acceleration techniques to address the shortcomings of existing wearable devices for ECG detection. The proposed approach to build a high-performance ECG rhythm abnormality monitoring coprocessor achieves a high degree of data reuse in time and space, which reduces the number of data flows, provides a more efficient hardware implementation and reduces hardware resource consumption than most existing models. The designed hardware circuit relies on 16-bit floating-point numbers for data inference at the convolutional, pooling, and fully connected layers, and implements acceleration of the computational subsystem through a 21-group floating-point multiplicative-additive computational array and an adder tree. The front- and back-end design of the chip was completed on the TSMC 65 nm process. The device has an area of 0.191 mm2, a core voltage of 1 V, an operating frequency of 20 MHz, a power consumption of 1.1419 mW, and requires 5.12 kByte of storage space. The architecture was evaluated using the MIT-BIH arrhythmia database dataset, which showed a classification accuracy of 97.69% and a classification time of 0.3 ms for a single heartbeat. The hardware architecture offers high accuracy with a simple structure, low resource footprint, and the ability to operate on edge devices with relatively low hardware configurations.


Subject(s)
Heart Defects, Congenital , Wearable Electronic Devices , Humans , Algorithms , Heart Rate , Signal Processing, Computer-Assisted , Neural Networks, Computer , Electrocardiography/methods
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