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1.
Biosens Bioelectron ; 262: 116542, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38991372

ABSTRACT

Continuous glucose monitors are crucial for diabetes management, but invasive sampling, signal drift and frequent calibrations restrict their widespread usage. Microneedle sensors are emerging as a minimally-invasive platform for real-time monitoring of clinical parameters in interstitial fluid. Herein, a painless and flexible microneedle sensing patch is constructed by a mechanically-strong microneedle base and a thin layer of fluorescent hydrogel sensor for on-site, accurate, and continuous glucose monitoring. The Förster resonance energy transfer (FRET)-based hydrogel sensors are fabricated by facile photopolymerizations of acryloylated FRET pairs and glucose-specific phenylboronic acid. The optimized hydrogel sensor enables quantification of glucose with reversibility, high selectivity, and signal stability against photobleaching. Poly (ethylene glycol diacrylate)-co-polyacrylamide hydrogel is utilized as the microneedle base, facilitating effective skin piercing and biofluid extraction. The integrated microneedle sensor patch displays a sensitivity of 0.029 mM-1 in the (patho)physiological range, a low detection limit of 0.193 mM, and a response time of 7.7 min in human serum. Hypoglycemia, euglycemia and hyperglycemia are continuously monitored over 6 h simulated meal and rest activities in a porcine skin model. This microneedle sensor with high transdermal analytical performance offers a powerful tool for continuous diabetes monitoring at point-of-care settings.

2.
Front Psychol ; 15: 1305121, 2024.
Article in English | MEDLINE | ID: mdl-38737952

ABSTRACT

Purpose: The purpose of this study was to examine the relationships among perceived physical literacy (PPL), knowledge of physical activity and fitness (PAF knowledge), and physical fitness. Methods: Undergraduates (N = 968, female = 414; Mage = 18.64) from a public university in central China completed a simplified Chinese version of the PPL instrument, an online test for PAF knowledge, and seven health-related physical fitness tests. The PPL includes three dimensions: (a) confidence and physical competence, (b) motivation, and (c) interaction with the environment. The fitness tests measured lung capacity, body mass index (BMI), and performances in 800 (female)/1000 (male) meters run, 50 meters dash (50 M), sit-up (female) / pull-up (male), standing long jump (SLJ), and sit-and-reach. Results: PPL and its dimensions significantly predicted six fitness test performances both in male (ß: -0.42 - 0.37; p < 0.01-0.05; R2: 0.01-0.13) and female (ß: -0.59 - 0.49; p < 0.01-0.05; R2: 0.03-0.13) students. PAF knowledge (ß: -0.17 - 0.18; p < 0.01-0.05; R2: 0.01-0.05) significantly predicted BMI (males) and performances in 50 M (females) and SLJ (females) tests. Conclusion: To support college students' fitness development and maintenance, tailored physical activity and fitness promotion programs are needed to strengthen students' PPL and PAF knowledge.

3.
J Toxicol ; 2023: 8832355, 2023.
Article in English | MEDLINE | ID: mdl-37168533

ABSTRACT

Background: Trimeresurus stejnegeri (T.s) accounts for most snakebites in southern China, which always leads to coagulation dysfunction. Coagulopathy due to venom is widely considered to be a characteristic phenomenon of the DIC-like syndrome. It is vitally important for first-line clinicians to improve this condition as soon as possible. However, clinical factors associated with coagulation function in Trimeresurus stejnegeri has not been well characterized yet. Materials: Patients bitten by vipers were admitted to the Emergency Department of a hospital in Shenzhen, southern China, from 2021 to 2022 and were retrospectively reviewed. Patient clinical characteristics and laboratory data were compared in the eligible patients bitten by T.s by their prothrombin time (PT), fibrinogen level (FIB), and platelet count on 2-3 days after bitten. Results: 105 patients were included in this study. The mean values of PT, FIB, and PLT are as follows: 12.8 ± 0.79 s, 2.25 ± 0.47 g/L, and 196.2 ± 57.1 × 109/L. Uric acid (UA) (367.9 ± 103.85), blood glucose (6.53 + 1.64) show negative trend of correlation, while CRP (2.12 + 4.17) shows positive trend of association with coagulation function. The smoke and systolic blood pressure may exert negative effects on PT and PLT, respectively. Logistic regression analysis indicated that uric acid (UA) shows significant connection with PT (OR = 1.15 and P value <0.0001), FIB (OR = 0.89 and P value = 0.026), and PLT (OR = 0.79 and P value = 0.007). CRP is also shown to be associated with FIB (OR = 1.33 and P value = 0.043). Conclusion: : Uric acid (UA) shows a significant association with PT, FIB, and PLT. CRP is related to FIB. Blood glucose shows a negative trend of correlation with PT. We do recommend physician should low the level of UA in some degree on the basis of injection of an antivenom serum.

4.
Materials (Basel) ; 15(3)2022 Feb 04.
Article in English | MEDLINE | ID: mdl-35161145

ABSTRACT

Incremental sheet metal forming characterized as increased flexibility and local plastic deformation is well suitable for low-production-run manufacturing and a new sample trial production of complex shapes. Thickness thinning is still an obstacle to the application of incremental forming. In this study, a novel mathematical algorithm based on a non-uniform rational B-spline (NURBS) surface was proposed and implemented which focuses on predicting and calculating the final thickness for arbitrary parts in incremental forming. In order to evaluate the validity of the proposed model, the finite element simulation and forming experiments of three kinds of parts, such as truncated cones, truncated pyramids and ellipsoid parts, were conducted. The thickness of theoretical prediction was compared with that of finite element simulation and experiment, and good agreements were obtained. The results show that the proposed model and the method are effective and robust for predicting the thickness of the formed parts in incremental sheet metal forming.

6.
PLoS One ; 10(7): e0131538, 2015.
Article in English | MEDLINE | ID: mdl-26171611

ABSTRACT

Mesoscale eddies in the subtropical oligotrophic ocean are ubiquitous and play an important role in nutrient supply and oceanic primary production. However, it is still unclear whether these mesoscale eddies can efficiently transfer CO2 from the atmosphere to deep waters via biological pump because of the sampling difficulty due to their transient nature. In 2007, particulate organic carbon (POC) fluxes, measured below the euphotic zone at the edge of warm eddy were 136-194 mg-C m-2 d-1 which was greatly elevated over that (POC flux = 26-35 mg-C m-2 d-1) determined in the nutrient-depleted oligotrophic waters in the Western North Pacific (WNP). In 2010, higher POC fluxes (83-115 mg-C m-2 d-1) were also observed at the boundary of mesoscale eddies in the WNP. The enhanced POC flux at the edge of eddies was mainly attributed to both large denuded diatom frustules and zooplankton fecal pellets based on scanning electron microscopy (SEM) examination. The result suggests that mesoscale eddies in the oligotrophic waters in the subtropical WNP can efficiently increase the oceanic carbon export flux and the eddy edge is a crucial conduit in carbon sequestration to deep waters.


Subject(s)
Carbon/chemistry , Organic Chemicals/chemistry , Pacific Ocean , Seawater/chemistry
7.
Nature ; 521(7550): 65-9, 2015 May 07.
Article in English | MEDLINE | ID: mdl-25951285

ABSTRACT

Internal gravity waves, the subsurface analogue of the familiar surface gravity waves that break on beaches, are ubiquitous in the ocean. Because of their strong vertical and horizontal currents, and the turbulent mixing caused by their breaking, they affect a panoply of ocean processes, such as the supply of nutrients for photosynthesis, sediment and pollutant transport and acoustic transmission; they also pose hazards for man-made structures in the ocean. Generated primarily by the wind and the tides, internal waves can travel thousands of kilometres from their sources before breaking, making it challenging to observe them and to include them in numerical climate models, which are sensitive to their effects. For over a decade, studies have targeted the South China Sea, where the oceans' most powerful known internal waves are generated in the Luzon Strait and steepen dramatically as they propagate west. Confusion has persisted regarding their mechanism of generation, variability and energy budget, however, owing to the lack of in situ data from the Luzon Strait, where extreme flow conditions make measurements difficult. Here we use new observations and numerical models to (1) show that the waves begin as sinusoidal disturbances rather than arising from sharp hydraulic phenomena, (2) reveal the existence of >200-metre-high breaking internal waves in the region of generation that give rise to turbulence levels >10,000 times that in the open ocean, (3) determine that the Kuroshio western boundary current noticeably refracts the internal wave field emanating from the Luzon Strait, and (4) demonstrate a factor-of-two agreement between modelled and observed energy fluxes, which allows us to produce an observationally supported energy budget of the region. Together, these findings give a cradle-to-grave picture of internal waves on a basin scale, which will support further improvements of their representation in numerical climate predictions.

8.
Luminescence ; 30(5): 619-24, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25349045

ABSTRACT

A novel and sensitive gas sensor was developed for the determination of benzene based on its cataluminescence (CTL) by oxidation in air on the surface of hollow magnesium silicate spheres. Luminescence characteristics and optimum conditions were investigated. Results indicated that the as-prepared magnesium silicate hollow spheres exhibited outstanding CTL properties such as stable intensity, high signal/noise values, and short response and recovery times. Under optimized conditions, benzene exhibited a broad linear range of 1-4500 ppm, with a correlation coefficient of 0.9946 and a limit of detection (signal-to-noise ratio (S/N) = 3) of 0.6 ppm, which was below the standard permitted concentration. The relative standard deviation (RSD) for 100 ppm benzene was 4.3% (n = 6). Furthermore, the gas sensor system showed outstanding selectivity for benzene compared with nine other common volatile organic compounds (VOCs). The proposed gas sensor showed good characteristics of high selectivity, fast response time and long lifetime, which suggested the promising application of magnesium silicate hollow spheres as a novel highly efficient CTL sensing material. The mechanism for the improved performance was also discussed based on the experimental results.


Subject(s)
Benzene/analysis , Luminescent Measurements/methods , Magnesium Silicates/chemistry , Air/analysis , Calibration , Equipment Design , Limit of Detection , Luminescent Measurements/instrumentation , Nanostructures/chemistry , Sensitivity and Specificity , Signal-To-Noise Ratio , Temperature
9.
Luminescence ; 30(3): 318-24, 2015 May.
Article in English | MEDLINE | ID: mdl-24990144

ABSTRACT

A three-dimensional hierarchical CdO nanostructure with a novel bio-inspired morphology is reported. The field emission scanning electronic microscopy, transmission electron microscopy and X-ray diffractometer were employed to characterize the as-prepared samples. In gas-sensing measurements, acetone and diethyl ether were employed as target gases to investigate cataluminescence (CTL) sensing properties of the CdO nanostructure. The results show that the as-fabricated CdO nanostructure exhibited outstanding CTL properties such as stable intensity, high signal/noise values, short response and recovery time. The limit of detection of acetone and diethyl ether was ca. 6.5 ppm and 6.7 ppm, respectively, which was below the standard permitted concentrations. Additionally, a principal components analysis method was used to investigate the recognizable ability of the CTL sensor, and it was found that acetone and diethyl ether can be distinguished clearly. The performance of the bio-inspired CdO nanostructure-based sensor system suggested the promising application of the CdO nanostructure as a novel highly efficient CTL sensing material.


Subject(s)
Acetone/analysis , Cadmium Compounds/chemistry , Ether/analysis , Luminescent Measurements/methods , Nanostructures/chemistry , Oxides/chemistry , Equipment Design , Limit of Detection , Luminescent Measurements/instrumentation , Oxidation-Reduction , Principal Component Analysis , Sensitivity and Specificity , Signal-To-Noise Ratio , Temperature , X-Ray Diffraction
10.
J Acoust Soc Am ; 134(4): 3272-81, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24116522

ABSTRACT

Ocean current profiling using ocean acoustic tomography (OAT) was conducted in the Kuroshio Current southeast of Taiwan from August 20 to September 15, 2009. Sound pulses were transmitted reciprocally between two acoustic stations placed near the underwater sound channel axis and separated by 48 km. Based on the result of ray simulation, the received signals are divided into multiple ray groups because it is difficult to resolve the ray arrivals for individual rays. The average differential travel times from these ray groups are used to reconstruct the vertical profiles of currents. The currents are estimated with respect to the deepest water layer via two methods: An explicit solution and an inversion with regularization. The strong currents were confined to the upper 200 m and rapidly weakened toward 500 m in depth. Both methods give similar results and are consistent with shipboard acoustic Doppler current profiler results in the upper 150 m. The observed temporal variation demonstrates a similar trend to the prediction from the Hybrid Coordinate Ocean Model.


Subject(s)
Acoustics , Oceanography/methods , Seawater , Sound , Water Movements , Acoustics/instrumentation , Doppler Effect , Equipment Design , Models, Theoretical , Motion , Oceanography/instrumentation , Oceans and Seas , Signal Processing, Computer-Assisted , Sound Spectrography , Taiwan , Temperature , Time Factors , Transducers
11.
Ann N Y Acad Sci ; 1042: 419-28, 2005 May.
Article in English | MEDLINE | ID: mdl-15965088

ABSTRACT

Recently, the mitochondrion has been considered as a novel pharmacological target for anticancer therapy due to its crucial role involved in arbitrating cell apoptosis. We have previously demonstrated that 488-nm laser irradiation induced a specific mitochondrial reactive oxygen species (mROS) formation and apoptotic death. In this study, we used a second generation of photosensitizers, the benzoporphyrin-derivative monoacid ring A (BPD-MA). We investigated specifically mechanisms at the mitochondrial level for BPD-MA coupled with 690-nm laser irradiation, the photodynamic effect (PDE) of BPD-MA, using conventional and laser scanning imaging microscopy in intact C6 glioma cells. We demonstrated BPD-MA localized mainly in the mitochondrial area. The phototoxicity induced by 1-10 J 690-nm laser irradiation was minor as compared to that induced by 488-nm laser irradiation. Unlike other mitochondrion-targeted photosensitizers, the dark toxicity induced by BPD-MA (0.05-5 mg/mL, effective doses used for the PDE) was relatively low. Nevertheless, the PDE of BPD-MA using 0.5 mg/mL coupled with 5J 690-nm irradiation induced profound and rapid (< 1 min) mitochondrial swelling, mROS formation, and severe plasma membrane blebbing as compared to that induced by 488-nm laser irradiation (< 10 min). Later, the PDE of BPD-MA resulted in positive propidium iodide cell-death stain and positive TUNEL apoptotic nuclear stain and DNA laddering. Finally, the PDT of BPD-MA also instantaneously promoted the mitochondrion to diminish its covalent binding with a mitochondrial marker, MitoTracker Green. We conclude that the PDT of BPD-MA targeted primarily and compellingly the mitochondrion to induce effective mitochondria-mediated apoptosis and thus may serve as a powerful photosensitizer for clinical cancer therapy.


Subject(s)
Apoptosis/drug effects , Apoptosis/radiation effects , Mitochondria/drug effects , Mitochondria/radiation effects , Photosensitizing Agents/toxicity , Porphyrins/toxicity , Animals , Cell Line, Tumor , Mitochondrial Swelling/drug effects , Mitochondrial Swelling/radiation effects , Rats , Time Factors , Verteporfin
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