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1.
Am J Primatol ; 86(8): e23636, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38824636

RESUMEN

As a central topic in Behavioral Ecology, animal space use involves dynamic responses to social and ecological factors. We collared 22 rhesus macaques (Macaca mulatta) from six groups on Neilingding Island, China, and collected 80,625 hourly fixes over a year. Using this high-resolution location data set, we quantified the macaques' space use at the individual level and tested the ecological constraints model while considering various environmental and human interfering factors. As predicted by the ecological constraints model, macaques in larger groups had longer daily path lengths (DPLs) and larger home ranges. We found an inverted U-shape relationship between mean daily temperatures and DPLs, indicating that macaques traveled farther on mild temperature days, while they decreased DPLs when temperatures were too high or too low. Anthropogenic food subsidies were positively correlated to DPLs, while the effect of rainfall was negative. Macaques decreased their DPLs and core areas when more flowers and less leaves were available, suggesting that macaques shifted their space use patterns to adapt to the seasonal differences in food resources. By applying GPS collars on a large number of individuals living on a small island, we gained valuable insights into within-group exploitation competition in wild rhesus macaques.


Asunto(s)
Sistemas de Información Geográfica , Fenómenos de Retorno al Lugar Habitual , Macaca mulatta , Animales , Macaca mulatta/fisiología , China , Masculino , Femenino , Ecosistema , Temperatura , Estaciones del Año , Islas
2.
Sensors (Basel) ; 23(13)2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37447748

RESUMEN

With the steady improvement of advanced manufacturing processes and big data technologies, modern industrial systems have become large-scale. To enhance the sensitivity of fault detection (FD) and overcome the drawbacks of the centralized FD framework in dynamic systems, a new data-driven FD method based on Hellinger distance and subspace techniques is proposed for dynamic systems. Specifically, the proposed approach uses only system input/output data collected via sensor networks, and the distributed residual signals can be generated directly through the stable kernel representation of the process. Based on this, each sensor node can obtain the identical residual signal and test statistic through the average consensus algorithms. In addition, this paper integrates the Hellinger distance into the residual signal analysis for improving the FD performance. Finally, the effectiveness and accuracy of the proposed method have been verified in a real multiphase flow facility.


Asunto(s)
Algoritmos , Industrias , Comercio , Tecnología
3.
Org Biomol Chem ; 20(23): 4709-4713, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35612896

RESUMEN

A one-pot catalyst-free reaction of o-hydroxyaryl azomethine ylides, vinyl pyridines and paraformaldehyde for the synthesis of benzopyrroxazines is reported, which offers a straightforward and atom-economical procedure for the preparation of benzopyrroxazine derivatives in moderate to excellent yields under mild conditions. A self-catalyzed [3 + 2] annulation through a mutual activation method and a sequential non-catalyzed [5 + 1] annulation process contribute to this strategy. The corresponding control experiments have been conducted to reveal the mechanism of this reaction.


Asunto(s)
Alquenos , Catálisis
4.
Nanotechnology ; 31(33): 335717, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32375129

RESUMEN

N-doped carbon-based materials are crucial electrically conductive additives and non-metal electrocatalysts for the oxygen reduction reaction. At present, many pieces of research are focused on the effects of micropore, mesopore and hierarchical pore structure on the catalytic activity, however, there are few works concerning the role of large-dimension through-hole structure. Hence, in this work, we prepare two kinds of carbon materials with large through-hole structure, i.e. N-doped carbon hollow-spheres and hollow-tubes, as the oxygen reduction catalysts. The synthesis follows template-free morphology-controlled pyrolysis, which is more convenient than the preparation of conventional N-doped nanotubes and graphene. The resultant N-doped carbon hollow-spheres and hollow-tubes evidently enhanced their ORR catalytic activity, remarkable long-term stability and methanol resistance. The large-dimension through-hole structure is found to account for the increase in mass transfer.

5.
Entropy (Basel) ; 23(1)2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33374991

RESUMEN

For ensuring the safety and reliability of high-speed trains, fault diagnosis (FD) technique plays an important role. Benefiting from the rapid developments of artificial intelligence, intelligent FD (IFD) strategies have obtained much attention in the field of academics and applications, where the qualitative approach is an important branch. Therefore, this survey will present a comprehensive review of these qualitative approaches from both theoretical and practical aspects. The primary task of this paper is to review the current development of these qualitative IFD techniques and then to present some of the latest results. Another major focus of our research is to introduce the background of high-speed trains, like the composition of the core subsystems, system structure, etc., based on which it becomes convenient for researchers to extract the diagnostic knowledge of high-speed trains, where the purpose is to understand how to use these types of knowledge. By reasonable utilization of the knowledge, it is hopeful to address various challenges caused by the coupling among subsystems of high-speed trains. Furthermore, future research trends for qualitative IFD approaches are also presented.

6.
Nanotechnology ; 29(46): 465402, 2018 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-30156562

RESUMEN

Development of bifunctional non-metal electrocatalyst for oxygen reduction reactions (ORRs) and oxygen evolution reactions (OERs) with high efficiency, durable stability and low cost is a crucial and challenging issue. However, the heteroatom-doped carbon material including a carbon-based conductive additive would be easily oxidized under the high potential needed for driving the OER. Besides, the interaction between the heteroatom-doped carbon material that possesses electrocatalyst activity and a carbon-based conductive additive is weak, affecting the performance of the electrocatalyst. In this context, we introduce CoS nanoparticles into a three-dimensional N-doped carbon framework (CoS/NCF) by a morphology-retaining pyrolysis of polyaniline/CoS framework precursor, in which the polyaniline framework provides abundant functional groups to nucleate and grow CoS nanoparticles while retaining its interconnected three-dimensional porous structure. Benefiting from (i) the lower OER potential of CoS nanoparticles than the electro-oxidation decomposition potential of a carbon material and (ii) the strong affinity of CoS nanoparticles for a N-doped carbon framework, higher stability than commercial Pt/C system and greater catalytic activity towards ORR with an onset potential of about 0.921 V versus reversible hydrogen electrode (RHE) are observed. Furthermore, only a potential of 1.515 V versus RHE is required for achieving a current density of 10 mA cm-2.

7.
J Fluoresc ; 27(6): 2111-2117, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28785903

RESUMEN

A novel fluorescein-based dual probe was designed and synthesized. The probe exhibited highly sensitive and selective colormetric response to Fe3+ and turn-on fluorescence response towards OCl- with very low detection limits of 100 and 50 nM, respectively. It was successfully applied for quantitative detection of Fe3+ and OCl- in real water samples. Moreover, probe 1 was expected to be a potentially powerful tool for studying and providing further insights into OCl- and Fe3+ chemistry in the near future.

8.
Angew Chem Int Ed Engl ; 55(5): 1805-9, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26696566

RESUMEN

The present communication reports a concept battery made by direct contact of magnesium foil with ultralight polyaniline (PANI) foam in the absence of additional electrolyte. Electrical current is allowed to be steadily released from the junction with a specific energy of 646 mWh g(-1) and specific capacity of 1247 mAh g(-1). Additionally, the battery offers an environmentally friendly route of hydrogen production along with discharging. Mechanistic studies indicated that the ubiquitous galvanic corrosion combined with decomposition of adsorbed trace water in the semi-conducting polymer foam enabled the generation of electricity, which overturns the traditional view. The higher moisture level is conducive to the discharge. This work is believed to open up new possibilities for the design of electrochemical batteries.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1300-5, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26415448

RESUMEN

Recently, the problem of food security is more and more serious, and people pay attention to mercury because of the toxic of it. A new approach for the determination of mercury content in foodstuff is devised. In this paper, first, we design and synthesis a new kind of fluorescent probe whose matrix based on rhodamine B, hydrazine hydrate and hydroxy benzaldehyde. Through the analysis of H-NMR spectra of the synthesized product L1, we confirm that the synthetic substance is the adjacent carboxyl benzaldehyde hydrazone structure generation of rhodamine B. Then, we measure the fluorescence signal intensity of the probe with different concentrations of mercury ions fully upon complexation by fluorescence spectrometer and we can study the relationship between the mercury ion concentration and the fluorescence intensity and draw the standard working curve. Following, It's time to discuss the microwave digestion processing of tea, after digestion we use the synthetic probe Li for determination of mercury content in tea. The experimental results show that the maximum excitation wavelength of the probe and coordination compound are 568. 05 and 560. 00 nm, the maximum emission wavelength are 587. 94 and 580. 00 nm. Then we can find the best testing conditions to improve the degree of accuracy, that is: room temperature, 50% the methanol solution, 3. 0 mL pH 4. 0 buffer solution, in the extent of 30 min. The experimental results show that Na+, K+, Ca2+, Cu2+, Zn2+, Al3+ have little impact on the fluorescence intensity of the:probe. Fe3+, Mg2+, Ba2+ has a weak enhancement to the fluorescence intensity of the probe. While a low concentrations of Hg2+ have an obviously enhanced effect on the fluorescence intensity of the probe. In contrast to other metal ions, the probe for Hg2+ has a good selectivity. Linear relationship between the magnitude of increase in fluorescence intensity and concentration of mercury ion was in the range of 5~20 ng . L-1 with detection limit (3S/N) of 1. 9 ng . L-1. The proposed method was applied to determination of mercury ion in samples of tea and sausage and the obtained result and sample recovery were all satisfactory. The methods of analysis instrument has the advantages of simple structure, sensitivity, high accuracy, good selectivity and less volume of simple, without the need for enrichment, being very practical.


Asunto(s)
Colorantes Fluorescentes/química , Análisis de los Alimentos/métodos , Mercurio/análisis , Rodaminas/química , Espectrometría de Fluorescencia , Tampones (Química) , Concentración de Iones de Hidrógeno , Iones , Límite de Detección
10.
Artículo en Inglés | MEDLINE | ID: mdl-38994582

RESUMEN

CONTEXT: Supplemental methotrexate (MTX) may affect the clinical course of Graves' disease (GD). OBJECTIVE: Evaluate efficacy of add-on MTX on medical treatment in GD. DESIGN: Prospective, open-label, randomized supplementation controlled trial. SETTING: Academic endocrine outpatient clinic. PATIENTS: One hundred and fifty-three untreated hyperthyroid patients with GD. INTERVENTION: Patients received MTX 10 mg/d with methimazole (MMI) or MMI only. MTX and MMI were discontinued at months 12-18 in euthyroid patients. MAIN OUTCOME MEASURES: Discontinuation rate at months 18 in each group. RESULTS: In the MTX with MMI group, the discontinuation rate was higher than the MMI group at months 15-18 (50.0 vs. 33.3%, P=0.043, 95% CI 1.020 to 3.922; and 55.6 vs 38.9%, P=0.045, 95%CI 1.011 to 3.815, respectively). The decrease in TRAb levels in the MTX with MMI group was significant from baseline to months 6 compared to the MMI alone group [MTX+MMI 67.22% (43.12-80.32), MMI 54.85% (33.18-73.76), P= 0.039) and became more significant from months 9 [MTX+MMI 77.79% (62.27-88.18), MMI 69.55% (50.50-83.22), P= 0.035] to months 18 (P < 0.01 in 15-18 months). A statistically significant difference between the levels of TRAb in the MTX with MMI group and the MMI group at 9-18 months. There were no significant differences in the levels of FT3, FT4 and TSH between two groups. No serious drug-related adverse events were observed in both groups(P=0.771). CONCLUSIONS: Supplemental MTX with MMI resulted in higher discontinuation rate and improvement in decreased TRAb levels to homeostatic levels faster than methimazole treatment alone at months 12-18.

11.
ISA Trans ; 125: 415-425, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34187683

RESUMEN

Incipient faults in running gear systems corrupt the overall performance of high-speed trains, increasing the necessity of fault detection and diagnosis whose purpose is to maintain the safe and stable operation of high-speed trains. For this purpose, a novel data-driven method, that utilizes Hellinger distance and slow feature analysis, is proposed in this study. By integrating Hellinger distance into slow feature analysis, a new test statistic is defined for detecting incipient faults in running gear systems. Furthermore, the hidden Markov method is developed for performing reliable fault diagnosis tasks. The salient strengths of the proposed method lie in its satisfactory fault detectability on the one hand and the considerable robustness against high-level noises on the other hand. Finally, the effectiveness of the proposed method is verified through a numerical example and a running gear system of high-speed trains under actual working conditions.

12.
J Endocrinol ; 255(1): 1-9, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35695299

RESUMEN

Graves' disease (GD) is characterized by dysregulation of the immune system with aberrant immune cell function. However, there have been few previous studies on the role of monocytes in the pathology of GD. The object of this study was to investigate whether and how monocytes participate in GD pathology. CD14+ monocytes were isolated from untreated initial GD patients and healthy controls. Then, RNA-seq was performed to investigate changes in global mRNA expression in monocytes and found that type I interferon (IFN) signalling was among the top upregulated signalling pathways in GD monocytes. Type I IFN-induced sialic acid-binding immunoglobulin-like lectin1 (SIGLEC1) expression was significantly upregulated in untreated GD patients and correlated with thyroid parameters. Patient serum SIGLEC1 concentrations were reduced after anti-thyroid drug treatment. Inhibiting SIGLEC1 expression could inhibit proinflammatory cytokine (IL-1ß, IL-6, IL-8, IL-10 and M-CSF) expression in monocytes. In conclusion, our study suggested that type I IFN-mediated monocyte activation could have a deleterious effect on the pathogenesis of GD. These observations indicated that the inhibition of type I IFN-activated monocytes/macrophages could have a therapeutic effect on GD remission.


Asunto(s)
Enfermedad de Graves , Interferón Tipo I , Lectinas , Proteínas de la Membrana , Monocitos , Enfermedad de Graves/genética , Enfermedad de Graves/inmunología , Humanos , Interferón Tipo I/genética , Interferón Tipo I/metabolismo , Lectinas/genética , Lectinas/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Monocitos/inmunología , Transducción de Señal
13.
Polymers (Basel) ; 14(7)2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35406148

RESUMEN

Solid electrolytes have been regarded as the most promising electrolyte materials for the next generation of flexible electronic devices due to their excellent safety and machinability. Herein, composite solid electrolytes (CSE) with "polymer in ceramic" are prepared by using lithium aluminum titanium phosphate (LATP) as a matrix and modified poly(ionic liquid) as a binder. The results revealed that adding a poly(ionic liquid)-based binder not only endowed good flexibility for solid electrolytes, but also significantly improved the ionic conductivity of the electrolytes. When the content of LATP in the CSE was 50 wt.%, the electrolyte obtained the highest ionic conductivity (1.2 × 10-3 S·cm-1), which was one order of magnitude higher than that of the pristine LATP. Finally, this study also characterized the compression resistance of the composite solid-state electrolyte by testing the Vickers hardness, and the results showed that the hardness of the composite solid-state electrolyte can reach 0.9 ± 0.1 gf/mm2 at a LATP content of 50 wt.%.

14.
Rapid Commun Mass Spectrom ; 25(18): 2633-40, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-23657958

RESUMEN

A metabonomic approach based on ultra-performance liquid chromatography coupled to mass spectrometry (UPLC/MS) was used to study the nephrotoxicity of rhizoma alismatis (RA) in rats. Potential biomarkers of RA toxicity were identified and the toxicological mechanism is discussed. Urine samples were collected from control and treated rats at various stages and analyzed by UPLC/MS in positive ionization mode. Histopathological analysis was used to evaluate renal function. The differences in the metabolic profiles of the control and treated rats were clearly distinguishable with principal components analysis (PCA) of the chromatographic data, and significant changes in 13 metabolite biomarkers were detected in the urine. This metabonomic method combined with PCA could discriminate the treated rats from the control rats on days 60, 120, and 180 after treatment, before serious organic renal damage was apparent on day 180 with histopathology. This research indicates that UPLC/MS-based metabonomic analysis of urine samples can be used to predict the chronic nephrotoxicity induced by rhizoma alismatis.


Asunto(s)
Alisma/química , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Enfermedades Renales/inducido químicamente , Espectrometría de Masas/métodos , Metabolómica/métodos , Rizoma/química , Orina/química , Animales , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/metabolismo , Medicamentos Herbarios Chinos/toxicidad , Humanos , Riñón/efectos de los fármacos , Riñón/metabolismo , Enfermedades Renales/metabolismo , Enfermedades Renales/orina , Masculino , Ratas , Ratas Wistar , Rizoma/efectos adversos
15.
Anal Bioanal Chem ; 399(3): 1363-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21107819

RESUMEN

A liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for the simultaneous determination of alisol A and alisol A 24-acetate from Alisma orientale (Sam.) Juz. in rat plasma using diazepam as an internal standard. A 200-µl plasma sample was extracted by methyl tert-butyl ether and the separation was performed on Kromasil C(18) column (150 × 4.6 mm, 5 µm) with the mobile phase of acetonitrile (containing 0.1% of formic acid)-water (73:27, v/v) at a flow rate of 0.8 ml/min in a run time of 10 min. The two analytes were monitored with positive electrospray ionization by selected ion monitoring mode. The lower limit of quantitation for both alisol A and alisol A 24-acetate were 10 ng/ml. The calibration curves were linear in the measured range 10-1,000 ng/ml for alisol A and 10-500 ng/ml for alisol A 24-acetate. The mean extraction recoveries were above 74.7% for alisol A and above 72.4% for alisol A 24-acetate from biological matrixes. The intra- and inter-day precision for all concentrations of quality controls was lower than 14.1% (RSD %) for each analyte. The accuracy ranged from -12.3% to 9.8% (RE %) for alisol A, and -8.6% to 14.2% (RE %) for alisol A 24-acetate. The method was successfully applied to the study on the pharmacokinetics of alisol A and alisol A 24-acetate in rat plasma.


Asunto(s)
Alisma/química , Colestenonas/sangre , Animales , Cromatografía Liquida , Masculino , Espectrometría de Masas , Conformación Molecular , Ratas , Ratas Wistar , Estereoisomerismo
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117467, 2020 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-31425863

RESUMEN

Herein, we presented two novel turn-on colorimetric and fluorescent probes based on a F- triggered SiO bond cleavage reaction, which displayed several desired properties for the quantitative detection for F-, such as high specificity, rapid response time (within 3 min) and naked-eye visualization. The fluorescence intensity at 574 nm (absorbance at 544 nm) of the solution was found to increase linearly with the concentration of F- (0.00-30.0 µM) with the detection limit was estimated to be 0.47 µM/0.48 µM. Based on these excellent optical properties, the probes were employed to monitor F- in real water samples and tea samples with satisfactory. Furthermore, it was successfully applied for fluorescent imaging of F- in living nude mice, suggesting that it could be used as a powerful tool to predict and explore the biological functions of F- in physiological and pathological processes.


Asunto(s)
Colorantes Fluorescentes/química , Fluoruros/análisis , Imagen Óptica/métodos , Espectrometría de Fluorescencia/métodos , Xantonas/química , Animales , Colorimetría , Límite de Detección , Modelos Lineales , Ratones , Ratones Desnudos , Té/química , Agua/química
17.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m928-9, 2009 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21583383

RESUMEN

In the title compound, [Cu(C(4)HN(3)O(4))(H(2)O)(3)](2)[Cu(2)(C(4)HN(3)O(4))(2)(H(2)O)(6)], both monomeric and dimeric mol-ecules are present in the solid state. In the monomeric compound, the Cu(II) atom is five-coordinated in a square-pyramidal configuration by one O atom and one N atom from one 1H-1,2,4-triazole-3,5-dicarboxyl-ate (TZDCA(2-)) ligand and three O atoms from water mol-ecules. In the centrosymmetric binuclear complex, each Cu(II) atom is six-coordinated in an octa-hedral geometry by one O atom and one N atom from one TZDCA(2-) ligand and four O atoms from water mol-ecules, two of which bridge the Cu(II) atoms. In the structure, there are intra-molecular O-H⋯O and N-H⋯O hydrogen bonds, and in the crystal, inter-molecular O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds link symmetry-related mol-ecules, forming a three-dimensional supra-molecular structure.

18.
RSC Adv ; 9(8): 4157-4161, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-35520197

RESUMEN

Solid-state electrolytes have emerged as a promising alternative to existing liquid electrolytes for next-generation flexible Li metal batteries with enhanced safety and stability. Nevertheless, the brittleness and inferior room temperature conductivity are major obstacles for practical applications. Herein, for the first time, we have fabricated a flexible lithium ion conductive glass-ceramic fiber by using a melt-spun homogeneous NASICON-type structured Li1.5Al0.5Ge1.5(PO4)3 (LAGP) glass melt and annealed at 825 °C. The annealed samples exhibited a higher lithium ion conductivity than the air-quenched sample due to the presence of a well-crystallized crystal grain in the annealed sample. Meanwhile, the ionic conductivity has shown an inverse relationship with the diameter of annealed LAGP glass-ceramic fibers. The results revealed that the annealed glass-ceramic fiber, with a diameter of 10 µm, resulted in lithium ion conductivity of 8.8 × 103 S cm-1 at room temperature.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 204: 657-664, 2018 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-29982156

RESUMEN

A rhodamine-based fluorescent probe for Cu2+ and ATP has been designed. The fluorescence intensity/absorbance was significantly enhanced upon the addition of Cu2+ owning to the opening of the spiro-ring of rhodamine, which quickly returned to the original level due to the reconstruction of the probe by the reacting with ATP. Cu2+/ATP-induced fluorescent intensity/aborbance changes showed a good linear relationship with the concentration of Cu2+/ATP in the range of 2-20 µM/0-10 µM with a detection limit of 0.1 µM/1.0 µM. The proposed method is simple in design and fast in operation, and is suitable for the reversible monitoring of Cu2+ and ATP in bioanalytical applications.


Asunto(s)
Adenosina Trifosfato/análisis , Cobre/análisis , Colorantes Fluorescentes/química , Rodaminas/química , Animales , Límite de Detección , Modelos Lineales , Ratones , Ratones Desnudos , Imagen Óptica , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia , Contaminantes Químicos del Agua/análisis
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