Detecting the concentration of reactive dyes and their hydrolyzed products is essential for controlling the dyeing process and is an important guide for upgrading and improving textile dyeing technology. In this study, capillary electrophoresis (CE) with UV detection was for the first time applied in a real trichromatic dyeing process to provide qualitative and quantitative determination of reactive dyes and their hydrolyzed forms. Here, three original reactive dyes (SES-Cl-red-195, SES-Cl-yellow-145, and SES-Cl-blue-194), their vinyl sulfone forms (VS-Cl-red-195, VS-Cl-yellow-145, and VS-Cl-blue-194), and complete hydrolyzed forms (HES-OH-red-195, HES-OH-yellow-145, and HES-OH-blue-194) could be baseline separated in our developed BGE comprised of 10.
View Article and Find Full Text PDFForests are experiencing increasingly severe drought stress worldwide. Although most studies have quantified how tree growth was affected by extreme droughts, how trees recover from different drought intensities are still poorly understood for different species. We used a network of tree-ring data comprising 731 Quercus mongolica trees across 29 sites, 312 Larix olgensis Henry trees from 13 sites, and 818 Larix principis-rupprechtii trees from 34 sites, covering most of their distribution range in northern China, to compare the influences of drought intensity on post-drought recovery.
View Article and Find Full Text PDFIn recent years, both domestic and international research on quadruped robots has advanced towards high dynamics and agility, with a focus on high-speed locomotion as a representative motion in high-dynamic activities. Quadruped animals like cheetahs exhibit high-speed running capabilities, attributed to the indispensable role played by their flexible spines during the flight phase motion. This paper establishes dynamic models of flexible spinal quadruped robots with different degrees of simplification, providing a parameterized description of the flight phase motion for both rigid-trunk and flexible-spine quadruped robots.
View Article and Find Full Text PDFIn this work, a simple, accurate, and rapid capillary electrophoresis with an indirect ultraviolet detection method was developed to simultaneous separate 10 biogenic amines. It was found that β-cyclodextrin and ethylene diamine tetraacetic acid facilitated the separation of tryptamine and tyramine, spermidine and spermine, respectively. The optimized background electrolytes consisted of 20.
View Article and Find Full Text PDFPressure-assisted electrokinetic injection (PAEKI) was applied for stacking of positively charged biogenic amines (BAs) to improve the sensitivity of capillary electrophoresis (CE). It is well known that the essential step for PAEKI is finding a stationary state of the running buffer such that the movement of the running buffer due to electroosmotic flow (EOF) is counterbalanced by external pressure in the opposite direction of the EOF under a given electric field. In order to find the balance point systematically and integrally, we studied the velocity of the whole BGE in the capillary by the impetus of opposite direction pressure (-0.
View Article and Find Full Text PDFA novel capillary electrophoresis - capacitively coupled contactless conductivity detection (CE-CD) method for the separation of 12 antibiotics, including four types of aminoglycosides, three types of fluoroquinolones, two types of tetracyclines, and three types of macrolides, was developed. Half of these antibiotics were not determined by ultraviolet (UV) because of their lack of UV-absorbing groups. Formic acid (FA) (pH 2.
View Article and Find Full Text PDFInt J Environ Res Public Health
December 2021
There is a rising concern that Olympic venue construction may affect the surrounding environment. The construction of Winter Olympic venues and competition zones is more likely to degrade the surrounding natural environment than the summer counterpart, considering the prominent land use change and extensive vegetation disturbance during the construction of ski trails in mountainous areas. Scientific assessment of the impact of this Winter Olympic Games construction on the surrounding ecological environment can be of significance for the construction of a Green Olympics.
View Article and Find Full Text PDFA reliable and simple CE method with dual CD and UV detection modes for simultaneous determination of major metal cations and whey proteins in milk samples was developed. Sample pretreatment comprised dilution, acidification to pH 4.55 with 10 mM AcOH and centrifugation.
View Article and Find Full Text PDFBackground: Spinal intraosseous schwannomas (SIS) are rare, and as yet have not been fully described in the literature. The first case of SIS was reported in 1971, and 24 cases of SIS have been reported so far. However, including the present case, there are only seven cases without spinal canal and neuroforamina involvement.
View Article and Find Full Text PDFIn this article, capillary electrophoresis was applied to investigate the chiral recognition mechanism for the enantioseparation on a well-known second-generation photodynamic therapy drug of benzoporphyrin derivative monoacid ring A, that is, verteporfin. In our previous study, cholate salts have been studied as the chiral selectors, which can realize baseline separation of the four verteporfin isomers. Aiming to reveal the chiral recognition mechanism, the separation effect of several kinds of chiral selectors was discussed.
View Article and Find Full Text PDFAn aminosulfonylation of alkenyl sulfonamides was reported. Using iodine as the catalyst, TBHP as the oxidant, and sulfonyl hydrazides as the sulfonyl radical sources, a variety of sulfonylmethyl piperidines, pyrrolidines and pyrazolines were obtained in moderate to excellent yields.
View Article and Find Full Text PDFClin Interv Aging
December 2019
Purpose: In this study, we aimed to investigate the role of lncRNA cancer susceptibility 11 (CASC11) and tumor necrosis factor (TNF-α) in postmenopausal osteoporosis (POP).
Methods And Materials: POP patients and healthy controls were included in this study and levels of CASC11 and TNF-α in plasma of those participants were measured by qPCR and Western blot, respectively. ROC curve was used for diagnostic analysis.
Tunneling conductance among nanoparticle arrays is extremely sensitive to the spacing of nanoparticles and might be applied to fabricate ultra-sensitive sensors. Such sensors are of paramount significance for various application, such as automotive systems and consumer electronics. Here, we represent a sensitive pressure sensor which is composed of a piezoresistive strain transducer fabricated from closely spaced nanoparticle films deposited on a flexible membrane.
View Article and Find Full Text PDFIntramolecular oxysulfonylation of alkenyl oximes was reported. Using iodine as the catalyst, TBHP as the oxidant, and sulfonyl hydrazides as the sulfonyl radical source, a variety of sulfonylated isoxazolines were obtained in moderate to excellent yields. Cyclic nitrones could also be readily obtained under the same conditions.
View Article and Find Full Text PDFA metal-free oxidative tandem coupling of N-allylbenzamide with aryl aldehydes was realized. This method allowed the 1,2-difunctionalization of the C═C double bond in N-allylbenzamides through simultaneous formation of two C(sp)-C(sp) bonds. In the presence of DTBP, 4-substituted 3,4-dihydroisoquinolin-1(2 H)-ones were obtained in satisfactory isolated yields.
View Article and Find Full Text PDFIn this study, a capillary zone electrophoresis (CZE) method was first developed to identify three microconstituents of isomeric pentacyclic triterpene acids (PTAs including oleanolic acid (OA), ursolic acid (UA) and betulinic acid (BA)) in Forsythiae Fructus (FF). The baseline separation of PTAs by CZE were eventually achieved in a background electrolyte (BGE) containing 50.0 mmol/L borax and 0.
View Article and Find Full Text PDFThe branched-chain amino acids (BCAAs) including leucine (Leu), isoleucine (Ile) and valine (Val) play a pivotal role in the human body. Herein, we developed capillary electrophoresis (CE) coupled with conventional UV detector to quantify underivatized BCAAs in two kinds of sport nutritional supplements. For direct UV detection at 195 nm, the BCAAs (Leu, two enantiomers of Ile and Val) were separated in a background electrolyte (BGE) consisting of 40.
View Article and Find Full Text PDFObjectives: This study aimed to evaluate the feasibility, local efficacy and long-term outcomes of microwave (MW) ablation for the treatment of hepatocellular carcinoma (HCC) that met up-to-seven criteria.
Methods: Between January 2007 and January 2012, 142 HCC patients with 294 nodules, which conformed to up-to-seven criteria, were enrolled into this retrospective study. All patients were followed up for more than 3 years after receiving MW ablation.
Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterized by progressive memory decline and cognitive impairment. Amyloid beta (Aβ) has been proposed as the causative role for the pathogenesis of AD. Accumulating evidence demonstrates that Aβ neurotoxicity is mediated by glutamate excitotoxicity.
View Article and Find Full Text PDFBiogenic amines (BAs) play significant roles in indicating human health or food quality. Aiming to simultaneously determine three structures (aliphatic, aromatic and heterocyclic) of underivatized BAs, we explored a simple and rapid capillary electrophoresis (CE) method only coupled with conventional UV detector for the separation of thirteen key BAs. The strategy is to choose a UV absorbing probe as co-ion in the background electrolyte (BGE), and different BAs could be characterized by positive or negative peaks according to the fact that their UV absorptivity coefficients at a certain wavelength are better or worse than that of the UV absorbing probe.
View Article and Find Full Text PDFThis paper aimed to build up a sensitive CE method for the analysis of tetracyclines (TCs) antibiotics (including tetracycline, chlorotetracycline, oxytetracycline, and doxycycline) with conventional UV detection. Here, the large volume sample stacking was applied to achieve in capillary preconcentration of the targets. To achieve large volume sample stacking, the essential step was a large volume of sample (around 83.
View Article and Find Full Text PDFThis article aims to build up a simple, rapid and accurate capillary zone electrophoresis (CZE) method for the separation of biogenic amines (BAs). Here, 10 key BAs (phenethylamine, histamine, tryptamine, tyramine, 5-hydroxytryptamine, octopamine, dopamine, norepinephrine, epinephrine and carnosine) owning significant functions were chosen for method development. The baseline separation and identification of 10 standards of the mixture by CZE were eventually achieved in 150.
View Article and Find Full Text PDFPressure-assisted electrokinetic injection (PAEKI) was applied to the highly sensitive enantioseparation of the positively charged drug citalopram (CIT) by capillary electrophoresis (CE). It was found that the injection discrimination occurred in electrokinetic injection (EKI) process due to the different dynamic equilibrium constant between chiral selector (sulfated-β-cyclodextrin, S-β-CD) and two isomers of CIT. Herein, it was proposed to use the background electrolyte (BGE) without chiral selector to fill the capillary, and then start the EKI step to eliminate the injection discrimination of free analytes.
View Article and Find Full Text PDFPressure-assisted electrokinetic injection (PAEKI) was applied for negatively charged verteporfin (VER) overloading and inline stacking, which targeted highly sensitive enantioseparation by CE. The essential step of PAEKI is a constant pressure used to counterbalance the electroosmotic flow (EOF), consequently, the large amount of analyte could be permitted into capillary and concentrated at the motionless boundary of the sample zone and background electrolyte (BGE). Aiming to know the balance, the velocity of the whole BGE in capillary by the impetus of pressure (0.
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