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1.
Artigo em Inglês | MEDLINE | ID: mdl-31478868

RESUMO

Constructing experiments to predict unknown miRNA-disease association is time-consuming, costly. Accordingly, new prediction model should be conducted to predict novel miRNA-disease associations. The performance of this method should be high and reliable. In this paper, a new computation model Logistic Weighted Profile-based Collaborative Matrix Factorization (LWPCMF) is put forward. In this method, weighted profile (WP) is combined with collaborative matrix factorization (CMF) to increase the performance of this model. And the neighbor information is considered. In addition, logistic function is applied to miRNA functional similarity matrix and disease semantic similarity matrix to extract valuable information. At the same time, by adding WP and logistic function, the known correlation can be protected. And Gaussian Interaction Profile (GIP) kernels of miRNAs and diseases are added to miRNA functional similarity network and disease semantic similarity network to augment kernel similarities. Then, a five-fold cross validation is implemented to evaluate the predictive ability of this method. Besides, case studies are conducted to view the experimental results. The final result contains not only known associations but also newly predicted ones. And the result proves that our method is better than other existing methods. This model is able to predict potential miRNA-disease associations.

2.
Chem Commun (Camb) ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482908

RESUMO

We report a novel metal-corrosion route beyond traditional top-down or bottom-up strategies for the mass production of 2D TMOs with a self-supported structure. The self-supported 2D Co3O4, a typical TMO, exhibits excellent electrocatalytic activity and stability in the oxygen evolution reaction surpassing those of commercial precious metal RuO2 catalysts at high currents.

3.
Exp Physiol ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31475750

RESUMO

NEW FINDINGS: What is the central question of this study? Research has reported that some sensory input can affect subliminal visual process, such as auditory and olfactory input. However, it is important to address whether tactile input, another form of elementary sensory input, could influence the interocular rivalry process. What is the main finding and its importance? We present several pieces of evidence regarding the influences of familiar tactile shapes and temperature on continuous flash suppression. Our findings provide support for the hypothesis that there is a cross-modal effect on unconscious visual semantic processing of Chinese characters. More specifically, tactile sensations affect subliminal processing of visual information. ABSTRACT: Tactile and visual sensations are the most vital human functions for obtaining environmental information. However, whether tactile information influences visual processing remains unclear. In this study, a breaking continuous flash suppression (b-CFS) paradigm was utilized to measure the extent to which tactile sensations facilitate visual processing unconsciously. In Experiment 1, cold and hot temperature finger stimulation served as primers for the words 'cold' and 'hot', which were in turn suppressed by CFS. In Experiment 2, subjects viewed the upright or inverted word 'cell phone' with or without tactile priming of holding a cell phone in their hand. Results demonstrated that the tactile primer significantly shortened the reaction time in the touch group compared to the control group in both experiments. Thus, the tactile sensation of a familiar article and/or temperature appears to facilitate corresponding visual semantic recognition to break CFS earlier. This article is protected by copyright. All rights reserved.

4.
PLoS Biol ; 17(9): e3000418, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31513574

RESUMO

Damaged acinar cells play a passive role in activating pancreatic stellate cells (PSCs) via recruitment of immune cells that subsequently activate PSCs. However, whether acinar cells directly contribute to PSC activation is unknown. Here, we report that the Hippo pathway, a well-known regulator of proliferation, is essential for suppression of expression of inflammation and fibrosis-associated genes in adult pancreatic acinar cells. Hippo inactivation in acinar cells induced yes-associated protein 1 (YAP1)/transcriptional coactivator with PDZ binding motif (TAZ)-dependent, irreversible fibrosis and inflammation, which was initiated by Hippo-mediated acinar-stromal communications and ameliorated by blocking YAP1/TAZ target connective tissue growth factor (CTGF). Hippo disruption promotes acinar cells to secrete fibroinflammatory factors and induce stromal activation, which precedes acinar proliferation and metaplasia. We found that Hippo disruption did not induce cell-autonomous proliferation but primed acinar cells to exogenous pro-proliferative stimuli, implying a well-orchestrated scenario in which Hippo signaling acts as an intrinsic link to coordinate fibroinflammatory response and proliferation for maintenance of the tissue integrity. Our findings suggest that the fibroinflammatory program in pancreatic acinar cells is suppressed under normal physiological conditions. While transient activation of inflammatory gene expression during tissue injury may contribute to the control of damage and tissue repair, its persistent activation may result in tissue fibrosis and failure of regeneration.

5.
J Environ Sci (China) ; 85: 138-146, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471020

RESUMO

Arsenic (As) is an omnipresent metalloid toxicant, which has elicited serious environmental pollution and health risky problems. Previous studies have uncovered that the As exposure could also cause markedly reduction of serum triglycerides in mice. However, the regulation mechanisms are still largely unknown. The present study is aimed to elucidate the molecular mechanisms of lncRNAs in As-induced lipid metabolic disequilibrium. We demonstrated that lncRNA PU.1 AS was significantly induced in the liver of As-feed mice companied with lower serum triglycerides contents; further in vitro experiment confirmed that PU.1 AS regulated liver cells lipid accumulation by nile red fluorescence staining. Intensive mechanistic investigations illustrated that PU.1 AS could interact with EZH2 protein to regulate its downstream target gene expression, and As-induced PU.1 AS attenuated EZH2-supppressed Sirt6 expression, thereafter leading to a decreased SREBP-1c protein expression, as well as the diminished synthesis of triglycerides in hepatocytes. In conclusion, this study provided a new lncRNA-related regulatory signaling pathway participating in As-induced abnormal lipid metabolism.


Assuntos
Arsênico/metabolismo , Metabolismo dos Lipídeos/genética , Animais , Camundongos , RNA Longo não Codificante/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1 , Triglicerídeos
6.
Appl Opt ; 58(24): 6629-6637, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503595

RESUMO

A combination of an image plane tilt method and usage of a multifocal lens array is proposed to reduce the intensity of the laser echo in surveillance and tracking imaging optical systems. The tilt of the image plane was used to reduce the energy of the laser echo, while the aberration due to the tilt of the image plane was effectively corrected by the multifocal lens array. To verify the feasibility and performance of the proposed method, an experimental setup was used, which consisted of a 2×2 lens array with a dual focal length. The experimental results showed that the measured variation law of the energy of the laser echo was consistent with the derived equation of the echo. It was demonstrated that the sharpness of the image edge increased for a tilt angle of 3° when the lens array was added. Thus, the multifocal lens array could effectively reduce the image edge blur caused by the tilted image plane.

7.
Acta Pharmacol Sin ; 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399700

RESUMO

Cocaine is one of the most abused illicit drugs worldwide. It is well known that the dopamine (DA) transporter is its major target; but cocaine also acts on other targets including nicotinic acetylcholine receptors (nAChRs). In this study, we investigated the effects of cocaine on a special subtype of neuronal nAChR, α3ß4-nAChR expressed in native SH-SY5Y cells. α3ß4-nAChR-mediated currents were recorded using whole-cell recordings. Drugs were applied using a computer-controlled U-tube drug perfusion system. We showed that bath application of nicotine induced inward currents in a concentration-dependent manner with an EC50 value of 20 µM. Pre-treatment with cocaine concentration-dependently inhibited nicotine-induced current with an IC50 of 1.5 µM. Kinetic analysis showed that cocaine accelerated α3ß4-nAChR desensitization, which caused a reduction of the amplitude of nicotine-induced currents. Co-application of nicotine and cocaine (1.5 µM) depressed the maximum response on the nicotine concentration-response curve without changing the EC50 value, suggesting a non-competitive mechanism. The cocaine-induced inhibition of nicotine response exhibited both voltage- and use-dependence, suggesting an open-channel blocking mechanism. Furthermore, intracellular application of GDP-ßS (via recording electrode) did not affect cocaine-induced inhibition, suggesting that cocaine did not alter receptor internalization. Moreover, intracellular application of cocaine (30 µM) failed to alter the nicotine response. Finally, cocaine (1.5 µM) was unable to inhibit the nicotine-induced inward current in heterologous expressed α6/α3ß2ß3-nAChRs and α4ß2-nAChRs expressed in human SH-EP1 cells. Collectively, our results suggest that cocaine is a potent blocker for native α3ß4-nAChRs expressed in SH-SY5Y cells.

8.
Bioresour Technol ; 292: 121957, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31430672

RESUMO

In this study, residue from saccharification and centrifugation of food waste ethanol fermentation was used as substrate to produce volatile fatty acids. The effects of different pH (5.5, 6.5, and uncontrolled) on the VFAs concentration, composition, acidogenic efficiency and microbial community distribution were investigated. The results showed that the highest concentration of VFAs was 267.8 ±â€¯8.9 mg COD/g VS at pH of 6.5, and the highest percentage of butyric acid (79.8%) was followed by propionic acid and acetic acid at the end of the reaction. Microbial analysis showed that the contents of Vagococcus and Actinomyces increased, while the contents of Bacteroides and Fermentimonas decreased during anaerobic fermentation. The comparative high pH induced the accumulation of butyric acid. This study provides a new idea for the step anaerobic fermentation of food waste to produce alcohol and acid simultaneously.

9.
Mikrochim Acta ; 186(8): 593, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31372825

RESUMO

A heterojunction microcomposite was synthesized that consists of ZnO nanoparticles (ZnO NPs) anchored on MoS2 microflowers (MoS2 MFs). The material is shown to enable trace level detection of the pollutant bisphenol A (BPA). The microcomposite was characterized by XRD, XPS, SEM and TEM. In addition, coupling reaction between phenolic estrogens and Pauly's reagents was adopted to greatly enhance the SERS signal. BPA display a characteristic Raman band at 1592 cm-1 which can be used for its selective detection. The assay is highly sensitive and has a 1 nM detection limit which is the lowest among the reported semiconductor substrates. Graphical abstract MoS2/ZnO MCs SERS substrate broke through the application barrier of semiconductor composite materials in SERS substrates. It also sheds light on a deeper understanding of the charge-transfer based enhancement mechanism.

10.
Neuroreport ; 30(13): 914-920, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31373972

RESUMO

This study was designed to investigate the cardiovascular effects of sulfur dioxide within the nucleus tractus solitarii. Sulfur dioxide or artificial cerebrospinal fluid was unilaterally applied into the nucleus tractus solitarii of rats, and the effects on blood pressure, heart rate, and arterial baroreflex sensitivity (ABR) were determined. To explore the mechanisms of the effects of intra-nucleus tractus solitarii sulfur dioxide, various inhibitors were applied prior to sulfur dioxide treatment. Unilateral microinjection of sulfur dioxide produced a dose-dependent decrease in blood pressure in anesthetized rats. Significant decreases in heart rate were also seen after unilateral microinjection of 20 and 200 pmol of sulfur dioxide (P < 0.05). Bilateral microinjection of sulfur dioxide into the nucleus tractus solitarii significantly decreased blood pressure and heart rate and also attenuated ABR. Pretreatment with glibenclamide or nicardipine within the nucleus tractus solitarii did not alter the hypotension or bradycardia (P > 0.05) induced by intra-nucleus tractus solitarii sulfur dioxide. Pretreatment with 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one, however, significantly attenuated this hypotension and bradycardia. Prior application of kynurenic acid or N(G)-Nitro-L-arginine methyl ester into the nucleus tractus solitarii partially diminished the hypotension and bradycardia induced by intra-nucleus tractus solitarii sulfur dioxide. Our present study shows that sulfur dioxide produces cardiovascular inhibitory effects in the nucleus tractus solitarii, predominantly mediated by glutamate receptors and the nitric oxide/cyclic GMP signal transduction pathway.

11.
Rev Environ Health ; 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31415239

RESUMO

Biobutanol offers several advantages and a larger market, that make it a biofuel to be studied with great interest. In fact, butanol has an energy content similar to that of gasoline, and it can be used as an alternative fuel to gasoline. It is a biofuel that is safe for the environment. The optimization of the production of butanol thus appears as an attractive option. Butanol production from food waste (FW) is a process for carbon recovery and a method for solid waste recycling. Recently, the use of FW and food processing waste (FPW) as raw material for the production of butanol has attracted much interest. However, an efficient fermentation process is vital to improve the production of biobutanol. To the best of our knowledge, no review on butanol production from FW has been presented so far. Thus, this review focuses on the characteristics of FW and its potential to produce butanol. In addition, the main factors that affect their use for the production of butanol are also discussed.

12.
Arch Virol ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31428915

RESUMO

Current antiviral therapies against hepatitis B virus (HBV) infections, such as treatment with nucleos(t)ide analogs (NAs) and interferon alpha, can significantly lower HBV DNA titers, eventually to undetectable levels. However, it is still difficult to completely eliminate the stable template of HBV, the covalently closed circular DNA (cccDNA), and this contributes to viral rebound when treatment is discontinued. HBV pregenomic RNA (pgRNA), which was recently found to be present in the enveloped mature HBV viral particle in blood, is tentatively regarded, with still accumulating clinical evidence, as a novel bona fide virological marker reflecting the amount and status of cccDNA when serum HBV DNA becomes undetectable. HBV pgRNA and DNA share almost identical sequences, and it is therefore difficult to differentiate pgRNA from viral DNA using normal PCR methods. To exclude interference from viral DNA, methods for measuring pgRNA usually require a selective DNA degradation step, which is complicated and time-consuming and also compromises the accuracy of detection. In this study, we developed a simplified quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay with improved accuracy achieved by probing the polyA tail of pgRNA. Using clinical serum samples, we observed that not all patients share the same 3' sequence, suggesting slight differences between HBV strains in the way they end transcription. We then designed and evaluated a universal primer and probe set for distinguishing HBV pgRNA from HBV DNA. Our results demonstrated that a one-step qRT-PCR assay could selectively amplify HBV pgRNA from a mixture of HBV RNA and DNA, which is valuable for clinical applications.

13.
Bioresour Technol ; 291: 121849, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31387051

RESUMO

Anaerobic digestion (AD) has been widely applied as an economic option for food waste (FW) treatment. In this study, the group treated with ethanol pre-fermentation (EP) for 12 h (EP12) exhibited the highest cumulative biogas yield (206 mL/g-volatile solid) during AD process and therefore it was used to illuminate the underlying metabolic processes of AD with EP. Carbon isotope labeled glucose was supplemented to FW substrate, and the EP process was found to alleviate the acidification inhibition with conducting extremely high carbon flux towards ethanol formation (43.7%). Then an efficient acetogenesis phase was also observed in EP12 group, because of high carbon conversion rate from ethanol to acetate. Overall, higher carbon conversion rate to methane (90.1%) during methanogenesis was found in the AD system with EP than in the control experiment (80.3%). Thus, we quantitatively confirmed that EP affects the AD metabolism of FW in terms of carbon flow distribution.


Assuntos
Alimentos , Metano/biossíntese , Anaerobiose , Biocombustíveis , Isótopos de Carbono , Etanol/metabolismo , Fermentação , Marcação por Isótopo
14.
Org Lett ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31449425

RESUMO

Design of a unique reaction pathway in transition-metal-catalyzed 1,6-enynes cyclization to construct valuable synthetic motifs is a significant challenge in organic chemistry. Herein, we report a Ru(II)-catalyzed formal [3 + 2] cycloaddition as an efficient method to prepare unprecedented bicyclo[3.3.0]octenes from readily available (E)-1,6-enynes. Mechanistic studies based on the deuterium labeling experiments and the DFT calculation disclose a reasonable mechanistic pathway, where a ruthenacyclopentene generated by an ene-yne oxidative cyclization undergoes a sequential ß-hydride elimination and intramolecular hydroruthenation to form a ruthenacyclohexene, producing the desirable bicyclo[3.3.0]octenes.

15.
Zhongguo Zhen Jiu ; 39(8): 901-6, 2019 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-31397140

RESUMO

OBJECTIVE: To realize real-time measurement and recording of temperature parameters inside acupoints during acupuncture treatment. METHODS: The fine wire thermocouple was embedded in hollow needle body as acupoint detection probe. According to the structure of acupoint temperature signal processing circuit, the Agilent 34420A nanovolt/micro-eurometer was used to design the technology method of acupoint temperature data acquisition, and an acupoint temperature collection platform was established. In addition, a verification experiment was conducted to verify the feasibility and stability of the system. RESULTS: The contrast experiment with mercury thermometer measurement showed that the temperature measurement curve of the designed acupoint temperature data collection platform was highly consistent with that of the standard thermometer, which verified the stability and reliability of the designed temperature measurement platform. The experiment of animal in-vivo measurement showed that the acupoint temperature probe had good feasibility for in-vivo acupoint temperature measurement. CONCLUSION: Acupoint temperature probe and acupoint temperature data collection technology can measure the temperature inside acupoints, and ensured the accuracy and veracity of the results. As an experimental method of acupoints temperature parameter collection, it can quantitatively record the temperature changes during the acupuncture treatment.

16.
J Neurosci ; 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31413075

RESUMO

Homeostatic regulation of synaptic strength allows for maintenance of neural activity within a dynamic range for proper circuit function. There are largely two distinct modes of synaptic plasticity that allow for homeostatic adaptation of cortical circuits: synaptic scaling and sliding threshold (BCM theory). Previous findings suggest that the induction of synaptic scaling is not prevented by blocking NMDA receptors (NMDARs) while sliding threshold model posits that the synaptic modification threshold of LTP and LTD readjusts with activity hence, the outcome of synaptic plasticity is NMDAR-dependent. While synaptic scaling and sliding threshold have been considered two distinct mechanisms, there are indications from recent studies that these two modes of homeostatic plasticity may interact or that they may operate under two distinct activity regimes. Here we report using both sexes of mouse that acute genetic knockout of the obligatory subunit of NMDAR or acute pharmacological block of NMDAR prevents experience-dependent homeostatic regulation of AMPAR-mediated miniature excitatory postsynaptic currents (mEPSCs) in layer 2/3 of visual cortex. This was not due to gross changes in postsynaptic neuronal activity with inhibiting NMDAR function as determine by c-Fos expression and 2 photon Ca2+ imaging in awake mice. Our results suggest that experience-dependent homeostatic regulation of intact cortical circuits is mediated by NMDAR-dependent plasticity mechanisms, which supports a sliding threshold model of homeostatic adaptation.SIGNIFICANCE STATEMENTProlonged changes in sensory experience lead to homeostatic adaptation of excitatory synaptic strength in sensory cortices. Both sliding threshold and synaptic scaling models can account for the observed homeostatic synaptic plasticity. Here we report that visual experience-dependent homeostatic plasticity of excitatory synapses observed in superficial layers of visual cortex is dependent on NMDA receptor function. In particular, both strengthening of synapses induced by visual deprivation and the subsequent weakening by reinstatement of visual experience were prevented in the absence of functional NMDA receptors. Our results suggest that sensory experience-dependent homeostatic adaptation depends on NMDA receptors, which supports the sliding threshold model of plasticity and input-specific homeostatic control observed in vivo.

17.
Int J Clin Oncol ; 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31414270

RESUMO

BACKGROUND: The aim of this study was to evaluate the prognostic veracity for disease-specific survival (DSS) of the eighth edition of the American Joint Committee on Cancer/Union for International Cancer Control tumor-node-metastasis staging system (TNM-8) compared with the seventh edition (TNM-7) in a Chinese population of patients with differentiated thyroid carcinoma (DTC) and to evaluate the impact of N1b redefinition and reclassification on prediction of survival. METHODS: A total of 569 DTC patients who underwent thyroid surgery in two Chinese hospitals were included in analysis to assess the predictive accuracy and N1b changes of TNM-8. Data from the Surveillance, Epidemiology and End Results (SEER) program were applied to validate the findings on N1b changes of TNM-8. Unadjusted DSS was calculated using the Kaplan-Meier method. Multivariable Cox proportional hazards models were used to evaluate the association of stage and lymph node metastasis (LNM) status with survival. The proportion of variation explained (PVE), Akaike information criterion (AIC), and Bayesian information criterion (BIC) were evaluated to compare model performance. RESULTS: When TNM-8 was applied, 39.7% of patients were downstaged relative to TMN-7. In comparison of TNM-7 and TMN-8, the PVE was 18.68% and 22.33%, the AIC was 704.22 and 680.50, and the BIC was 702.98 and 679.24, respectively. In 569 Chinese patients with DTC, levels I-V LNM was significantly related to poorer DSS compared with N0 and level VI LNM. Among patients aged ≥ 55 years, those with levels I-V and VII LNM had significantly worse DSS than those with N0 and Level VI LNM. In the SEER dataset, patients with levels I-V and VII LNM had significantly worse DSS compared with those with N0 and Level VI LNM, especially in older patients (age ≥ 55 years). CONCLUSIONS: TNM-8 staged a significant number of Chinese patients into lower stages and improved the accuracy of predicting DSS compared with TNM-7. However, changes in lateral LNM definition and classification of TNM-8 have a significant prognostic implication for patients with DTC, especially older patients (≥ 55 years). Our data suggest that a modified TNM staging system would be more useful for predicting mortality and determining a proper treatment strategy in patients with DTC.

18.
Fertil Steril ; 112(1): 89-97.e1, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277770

RESUMO

OBJECTIVE: To evaluate whether intrauterine injection of hCG before embryo transfer can improve IVF-ET outcomes. DESIGN: Meta-analysis. SETTING: Not applicable. PATIENT(S): Infertile women who underwent IVF-ET and received an intrauterine injection of hCG before ET. INTERVENTION(S): Infertile women treated with or without intrauterine hCG injection before ET. MAIN OUTCOME MEASURE(S): The primary outcomes were live birth rate (LBR), ongoing pregnancy rate (OPR), and clinical pregnancy rate (CPR), and the secondary outcomes were implantation rate (IR) and miscarriage rate (MR). Odds ratios with 95% confidence intervals (CIs) and successful ET rates were pooled to determine the effects of hCG on IVF-ET outcomes. RESULT(S): Fifteen randomized controlled trials (RCTs) with a total of 2,763 participants were included. Infertile women in the experimental group (treated with intrauterine hCG injection before ET) exhibited significantly higher LBR (44.89% vs. 29.76%), OPR (48.09% vs. 33.42%), CPR (47.80% vs. 32.78%), and IR (31.64% vs. 22.52%) than those in the control group (intrauterine injection of placebo or no injection). Furthermore, MR was significantly lower (12.45% vs. 18.56%) in the experimental group than in the control group. CONCLUSION(S): The findings of this meta-analysis indicate that intrauterine injection of hCG can improve LBR, OPR, CPR, and IR after IVF-ET cycles. In addition, different timing and dosages of hCG administration may exert different effects on IVT-ET outcomes. Notably, infertile women treated with 500 IU hCG within 15 minutes before ET can achieve optimal IVF-ET outcomes.

19.
J Chromatogr Sci ; 57(8): 738-744, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31318427

RESUMO

Morus alba L. is a medicinal plant that contains a high amount of caffeoylquinic acids such as 3-caffeoylquinic acid (3-CQA), 5-caffeoylquinic acid (5-CQA) and 4-caffeoylquinic acid (4-CQA). This study aimed to establish a fast and efficient method for separating caffeoylquinic acids from mulberry leaves by using high-speed countercurrent chromatography coupled with macroporous resin. D101 resin showed better adsorption and desorption capacity for three caffeoylquinic acids among six macroporous resin adsorbents. The contents of 3-CQA, 5-CQA and 4-CQA reached for 4.77%, 18.95% and 9.84% through one cycle of D101 resin, which were 3.13-fold, 4.57-fold and 4.78-fold more than those in crude extracts, respectively. With a two-phase solvent system of ethyl acetate-water (1:1, V/V), >93% purity of target compounds were obtained in one cycle during 150 min with the recovery yields of 80.59%, 99.56% and 94.21% for 3-CQA, 5-CQA and 4-CQA, respectively. The structural identification of target compounds was carried out by ESI-MS, 1H NMR and 13C NMR spectra. The present result represented an easy and efficient separation strategy for the utilization of mulberry resource.

20.
Rev Sci Instrum ; 90(6): 066102, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31254978

RESUMO

In this note, a portable ultrawideband (UWB) electromagnetic radiator is developed based on a transistorized pulser with the peak power of 1.4 MW, the rise time less than 150 ps, and the repetition frequency of 50 kHz. To generate high-amplitude pulses, a 100-stage Marx circuit with parallel connection of multiple transistors is proposed. To improve the pulse repetition rate, the parallel charging Marx circuit is adopted with ferrite beads connected in series between stages for high isolation of pulses. In order to radiate the UWB electromagnetic pulse directionally, a compact combined antenna array is fabricated and connected with the pulser via a coaxial feeding module. The effective potential of the UWB radiator reaches 10.5 kV with the band range (-10 dB) from 173 MHz to 2.32 GHz.

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