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1.
Sci Total Environ ; 924: 171573, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38462005

RESUMEN

The critical impacts of microclimate on carbon (C) cycling have been widely reported. However, the potential effects of global change on wetland microclimate remain unclear, primarily because of the absence of field manipulative experiment in inundated wetland. This study was designed to examine the effects of nighttime warming and nitrogen (N) addition on air, water, and sediment temperature and also reveal the controlling factors in a Phragmites australis dominated freshwater wetland on the North China Plain. Nighttime warming increased daily air, water, and sediment temperature by 0.24 °C, 0.27 °C, and 0.36 °C, respectively. The diurnal temperature range of water was decreased by 0.44 °C under nighttime warming, whereas warming had no effect on diurnal temperature range of air and sediment. In addition, N addition caused a reduction of 0.20 °C and 0.14 °C in daily water and sediment temperature by increasing vegetation coverage. There was a significant interaction between nighttime warming and N addition on water temperature. Furthermore, the vapor pressure deficit is the main factor affecting the extent of the warming-induced increases in air temperature. The changes of height and leaf area index of Phragmites australis are responsible for the cooling effects in the N addition plots. This study provides empirical evidence for the positive climate warming - microclimate feedback in freshwater wetland. However, N deposition leads to decreased water and sediment temperature. Our findings highlight the importance of incorporating the differential impacts of nighttime warming and N addition on air, water, and sediment temperature into the predictions of wetland C cycling responses to climate change.

2.
STAR Protoc ; 5(1): 102907, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38412101

RESUMEN

Here, we present a finite element method-based scheme for solving coupled partial differential equations (PDEs) for the analysis of lithiation-induced stress in largely deformed spherical nanoparticles via the PDE module in COMSOL. We describe steps for software installation and setting PDEs, initial/boundary conditions, and mesh parameters. We then detail procedures for dividing the mesh and analyzing lithium trapping during electrochemical cycling. This protocol can also be extended to analyze a wide range of problems involving diffusion-induced stress. For complete details on the use and execution of this protocol, please refer to Li et al.1.


Asunto(s)
Dietilestilbestrol/análogos & derivados , Nanopartículas , Difusión , Nanopartículas/efectos adversos
3.
Nat Commun ; 14(1): 6134, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37783711

RESUMEN

Artificial neural networks (ANNs) have gained considerable momentum in the past decade. Although at first the main task of the ANN paradigm was to tune the connection weights in fixed-architecture networks, there has recently been growing interest in evolving network architectures toward the goal of creating artificial general intelligence. Lagging behind this trend, current ANN hardware struggles for a balance between flexibility and efficiency but cannot achieve both. Here, we report on a novel approach for the on-demand generation of complex networks within a single memristor where multiple virtual nodes are created by time multiplexing and the non-trivial topological features, such as small-worldness, are generated by exploiting device dynamics with intrinsic cycle-to-cycle variability. When used for reservoir computing, memristive complex networks can achieve a noticeable increase in memory capacity a and respectable performance boost compared to conventional reservoirs trivially implemented as fully connected networks. This work expands the functionality of memristors for ANN computing.

4.
Zhongguo Gu Shang ; 35(11): 1087-94, 2022 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-36415197

RESUMEN

OBJECTIVE: To compare the effects of different concentrations of linolenin on inhibiting apoptosis of chondrocytes in the growth plate, and to screen the optimal concentration of linolenin, so as to provide theoretical support for delaying epiphyseal closure and promoting long bone growth in rats. METHODS: Two 4-week-old male SD rats (SPF grade) with a body mass of 80 g were selected. The growth plate cartilage of rat tibia and femur was dissected and isolated in vitro to obtain growth plate chondrocytes for culture. The chondrocytes were observed and identified by inverted phase contrast microscope and typeⅡ collagen immunofluorescence test, and then 20 ng/ml IL-1ß was used to induce apoptosis of growth plate chondrocytes as model group, and added with 1, 10, 20, 40 µM linolenin as the experimental group, and 5 µM letrozole as the positive control group. The cells were cultured for 24 and 48 hours respectively. The drug promoted cell proliferation was observed by MTT method, and the drug inhibited cell apoptosis was detected by flow cytometry. RESULTS: Contents 1, 10, 20, 40 µM could promote cell proliferation in varying degrees, and the principle was that the drug inhibits IL-1ß induced chondrocyte apoptosis in the growth plate, and the optimal concentration of drugs to inhibit apoptosis was 20 µM. CONCLUSION: The appropriate concentration of linseed lignans can significantly inhibit the apoptosis of chondrocytes in the growth plate of rats, and the optimal drug concentration is 20 µM. It provides possibility for delayed bone closure and longer growth time to promote bone growth during development.


Asunto(s)
Lino , Lignanos , Masculino , Ratas , Animales , Placa de Crecimiento , Condrocitos , Ratas Sprague-Dawley , Apoptosis , Lignanos/farmacología
5.
Artículo en Inglés | MEDLINE | ID: mdl-35270459

RESUMEN

The anti-glare facilities in median strips are designed to block opposing headlights in order to avoid disability glare, but a large amount of headlight leakage results in uncomfortable glare, to the point that drivers can barely detect dangerous obstacles or road conditions. This paper aims to explore the glare range under high-beam headlights on drivers' visual requirements. Based on an analysis of the mechanism of headlight glare, this paper proposes a subjective headlight glare scale, and classifies glare discomfort into two categories: interference glare, and acceptability glare. Combining the scales, 24 drivers and a standard light-emitting diode automotive headlamp were used to conduct glare effect tests. The size of the laboratory that closes to scotopic vision is 12 m × 6 m. The illuminance thresholds of disability glare-interference glare (DGIG) and interference glare-acceptability glare (IGAG), along with the spatial distribution of each glare level, were collected at the longitudinal distances of 3 m, 5 m, 7 m, 10 m, and 12 m. Meanwhile, the illuminance threshold and the spatial distribution of each glare level up to a longitudinal distance of 120 m were calculated. The results indicate that disability glare is distributed in the central area, while interference glare and acceptability glare are distributed from the center to the margins. At the same longitudinal distance, the vertical illuminance of the driver's eye under the same glare level is almost equal. In the range of a longitudinal distance of 120 m, the spatial distribution of each glare level enlarges with each increase in longitudinal distance. The results can provide scientific evidence for calculating the reasonable heights of anti-glare facilities for expressways with different alignments.


Asunto(s)
Conducción de Automóvil , Deslumbramiento
6.
Artículo en Inglés | MEDLINE | ID: mdl-35270742

RESUMEN

Pavement marking in daylight with poor quality cannot provide a reference for drivers to specify their own position relative to nearby vehicles. Luminance and Correlated color temperature (CCT) of sunlight is of importance for daytime visibility of in-service pavement markings, which lacks detailed consideration. This paper aims to explore the daytime visibility requirements of in-service pavement markings considering the influence of natural light characteristics. Based on analyzing the mechanism and impact factors of daytime visibility of pavement markings, a subjective scale of pavement markings state in the drivers' field of view was proposed and a short and bold line was recommended as the standard state. Thirty-six tested drivers were randomly selected to detect white and yellow markings of both 15 cm and 20 cm width under 2000 to 23,000 lx and 5500 to 8500 K for outdoor natural light environment. The luminance contrast of the pavement marking to the surrounding road surface ranged from 0 to 10. The result indicated that the natural light with 2000 to 3000 lx and 7500 to 8500 K is the most unfavorable light environment for drivers to recognize pavement markings during daytime. The detection distance is becoming longer with the increase of luminance contrast. The detection distance does not increase with the increase of luminance contrast when the luminance contrast of white markings is greater than 4 and that of yellow markings is greater than 3. The model was established expressing the relationship between luminance contrast and Qd contrast. The preview time 3.65 s was selected to calculate the minimum requirements of Qd at speeds of 60, 80, 100 km/h, respectively, for different types of markings. The results can provide scientific evidence for quality evaluation and maintenance management of pavement markings in service for daytime visibility.

7.
Ann Med ; 54(1): 622-632, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35175162

RESUMEN

OBJECTIVE: Previous study have shown that lipid accumulation product (LAP), visceral adiposity index (VAI), triglyceride/high-density lipoprotein cholesterol ratio (TG/HDL-C) and triglycerides/glucose index (TyG index) could be simple clinical indicators of insulin resistance (IR) based on anthropometric and/or biochemical parameters. However, the rational and preferred surrogate marker of IR in different population has yet to be validated. The aim of this study was evaluating the practicability of the LAP, VAI, TG/HDL-C, and TyG in predicting IR in middle-aged Chinese population. METHODS: A cross-sectional study was conducted in 569 Chinese participants (mean age was 48.5; man 67.7%), and each participant completed a questionnaire survey, anthropometric measurement, and biochemical testing. One-way ANOVAs, Chi-squared test, Pearson's correlation, and multiple logistic regression were used to evaluate the association between VAI, LAP, TG/HDL-C, and TyG with IR. To correctly discriminate individuals with insulin resistance, a receiver operating characteristic (ROC) analysis was conducted for each evaluated variable and the overall diagnostic accuracy was quantified using the area under the ROC curve (AUC). The AUC of evaluated variables were compared using a nonparametric approach. The optimal cut-off points were determined by the Youden's index, and the corresponding sensitivity and specificity were provided. RESULTS: Significant positive correlation was identified between HOMA-IR with TG/HDL-C (r = 0.306), VAI (r = 0.217), LAP (r = 0.381), and TyG (r = 0.371), respectively (all p < .001). After adjustment for potential confounders of IR, compared with the lowest tertiles, odds ratio (95% CI) having IR in the highest tertiles of TG/HDL-C, VAI, LAP and TyG were 6.07 (2.89-12.71), 10.89 (4.37-27.13), 4.68 (2.00-10.92), and 12.20 (5.04-29.56). The area under ROC curves to predict HOMA-diagnosed IR was 0.773 for TG/HDL-C, 0.767 for VAI, 0.806 for LAP, and 0.800 for TyG, respectively. Among those, LAP showed the greatest value of AUC [0.806 (0.763-0.850)] and highest specificity (0.804). CONCLUSION: Compared with other indicators, the LAP and TyG are simple, relatively accurate, clinically available surrogate markers of insulin resistance in middle-aged population in Hefei, China. Among 4 evaluated parameters, the LAP have the highest specificity and the TyG have the highest sensitivity.Key MessagesLAP and TyG could be used as simple and alternative methods to identify the individuals at risk for insulin resistance.LAP and TyG have relatively high predictive ability in diagnosis of IR compared with VAI and TG/HDL-C.No significant difference is observed between LAP and TyG in the ability of predicting insulin resistance.


Asunto(s)
Resistencia a la Insulina , Producto de la Acumulación de Lípidos , Biomarcadores/análisis , Glucemia/análisis , China/epidemiología , HDL-Colesterol , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Triglicéridos
8.
Ecol Evol ; 10(20): 11838-11846, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33145004

RESUMEN

The distribution of mangroves is influenced by the environment. We aimed to understand the ecological adaptability of various mangrove species within the range of the exotic species, Sonneratia apetala Buch.-Ham., in Dongzhai Harbor, Hainan Island, China. We used three niche breadth indexes (Simpson, Levins, and Shannon-Weiner) and two niche overlap indexes (Pianka and Levins) to quantitatively determine the niche characteristics of nine mangrove species. The results showed that the order of the niche breadth values of mangrove species was as follows: Aegiceras corniculatum (Linn.) Blanco > Kandelia obovata Sheue et al. > Bruguiera gymnorrhiza (L.) Poir. > Avicennia marina (Forsk.) Vierh. Hailanci > S. apetala > S. caseolaris (L.) Engl. > Rhizophora stylosa Griff > Ceriops tagal (Perr.) C. B. Rob. > B. sexangula (Lour.) Poir. Pearson correlation analysis revealed that the niche breadth of each population was significantly correlated with the importance value of the population in the whole sample (R1 = R2 = 0.771, R3 = 0.644, p < .05). The nine mangrove species were divided into three groups by Bray-Curtis cluster analysis; the groups were similar to the distribution of mangrove species in the natural state as determined by tide level. Niche similarity analysis showed that the niche similarity of most mangroves ranged between 0.5 and 0.8 and that the species pairs A. corniculatum-B. gymnorrhiza, A. corniculatum-Avicennia marina, and K. obovata-S. caseolaris were characterized by large niche similarity ratios. Although it had a moderate niche breadth, S. apetala had a relatively broad niche overlap with mangroves in the mid- and low-tide zones (S. caseolaris, A. corniculatum, K. obovata, and Avicennia marina), a moderate overlap with B. gymnorrhiza and R. stylosa, only a slight overlap with C. tagal, and no overlap with B. sexangular. There was no obvious linear relationship between niche width and niche overlap of mangroves. Due to its inefficiency in utilizing certain resources and relatively high degree of resource selection, it seems likely that S. apetala will not pose a threat to the survival of native plants, let alone completely replace native species.

9.
Eur J Drug Metab Pharmacokinet ; 45(4): 453-466, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32170643

RESUMEN

BACKGROUND AND OBJECTIVES: Tacrolimus is a widely used immunosuppressive agent with narrow therapeutic window. Nowadays, tacrolimus has gained acceptance as a therapeutic option in myasthenia gravis (MG) treament, however, little is known about its pharmacokinetic characteristics in MG population. In this study, we aimed to investigate the population pharmacokinetic (PopPK) of tacrolimus in patients with MG and to develop model-informed dosing regimens. METHODS: Trough concentrations of tacrolimus (267 measurements) and cytochrome P450 (CYP) genotypes were determined in 97 Chinese adults. The non-linear mixed-effects model was used for PopPK modeling. Monte Carlo simulations based on the established model were employed to design dosing regimens. RESULTS: The PopPK model was described using a one-compartment model with first-order absorption and elimination. The mean apparent clearance (CL/F) of tacrolimus was 17.1 L/h, with a between-subject variability of 20.1%. Covariate screening of demographic characteristics, blood test results, co-medications, and CYP3A5*3 or CYP3A4*1G polymorphisms showed that the CYP3A5*3 genotype and co-administration of a Wuzhi capsule significantly affected tacrolimus CL/F. CONCLUSIONS: For patients with the CYP3A5*3*3 allele, the required tacrolimus dose for 75% of subjects to achieve target trough concentrations of 4.8-15 ng/mL was 2 mg every 12 h (q12h). For patients with the CYP3A5*1*1 allele, the required dose was 2 mg tacrolimus q12h with a Wuzhi capsule, and for patients with the CYP3A5*1*3 allele, the required dose was 3 mg of tacrolimus q12h or 4 mg q24h co-administered with a Wuzhi capsule. This model could be employed to optimize individualized therapies for patients with MG.


Asunto(s)
Inmunosupresores/farmacocinética , Modelos Biológicos , Miastenia Gravis/tratamiento farmacológico , Tacrolimus/farmacocinética , Adolescente , Adulto , Anciano , Pueblo Asiatico , China , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Cálculo de Dosificación de Drogas , Monitoreo de Drogas , Femenino , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/sangre , Masculino , Persona de Mediana Edad , Miastenia Gravis/sangre , Miastenia Gravis/etnología , Variantes Farmacogenómicas , Medicina de Precisión , Estudios Prospectivos , Tacrolimus/administración & dosificación , Tacrolimus/sangre , Resultado del Tratamiento , Adulto Joven
10.
Eur J Drug Metab Pharmacokinet ; 45(2): 163-172, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31792726

RESUMEN

Delayed or missed doses are unavoidable in clinical practice and remain as a challenge that threatens a patient's health and quality-of-life, especially in the pharmacotherapy of chronic disease treatment. Unfortunately, information or guidance concerning the management of delayed or missed doses is scarce, precluding clinicians or clinical pharmacologists from instructing patients in a precision dosing manner. It is therefore urgent to develop remedial strategies to inform patients of alternative dosing regimens in compensation for the loss of efficacy due to delayed or missed doses and minimize unintended clinical consequences. Studies aiming to establish remedial regimens have been conducted since the 1980s for oral contraceptives and antihypertensive agents, using the controlled substitution of placebos for active medications. However, it appeared to be unethical in many areas of pharmacotherapy due to deliberately discontinuing or restarting the medication. Alternatively, pharmacometric modeling and simulation offers an opportunity to investigate the effect of various non-adherence scenarios on pharmacokinetic profiles and establish the optimum remedial dosing regimen in a time-effective and systematical way. This review provides a general overview of procedures and strategies on how to develop remedial dosing regimens based on pharmacometric approaches through the scrutiny of case examples in the literature.


Asunto(s)
Cumplimiento de la Medicación , Modelos Biológicos , Preparaciones Farmacéuticas/administración & dosificación , Esquema de Medicación , Humanos , Farmacocinética , Calidad de Vida
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