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Phenols and anilines are of extreme importance for medicinal chemistry and material science. The development of efficient approaches to prepare both compounds has thus long been a vital research topic. The utility of phenols and anilines directly reflects the identity and pattern of substituents on the benzenoid ring. Electrophilic substitutions remain among the most powerful synthetic methods to substituted phenols and anilines, yet in principle achieving ortho- and para-substituted products. Therefore, the selective preparation of meta-substituted phenols and anilines is the most significant challenge. We herein report an efficient copper-catalyzed dehydrogenation strategy to exclusively synthesize meta-carbonyl phenols and anilines from carbonyl substituted cyclohexanes. Mechanistic studies indicate that this transformation undergoes a copper-catalyzed dehydrogenation/allylic hydroxylation or amination/oxidative dehydrogenation/aromatization cascade process.Phenols and anilines are of extreme importance for medicinal chemistry and material science but the selective preparation of meta-substituted phenols and anilines remains challenging. Here the authors report an efficient copper-catalyzed dehydrogenation strategy to exclusively synthesize meta-carbonyl phenols and anilines from carbonyl substituted cyclohexanes. [ABSTRACT FROM AUTHOR]

Interindividual differences in personal values are prevalent both within and across societies. Interindividual differences in personal value and the relationships with mental health disorders and life satisfaction remain to be holistically considered, especially in China. The present study aims to characterize personal value profiles based on Schwartz's theory model and to examine differences in several mental health-related disorders and life satisfaction potentially across these profiles. Using convenience sampling, a sample of 8,540 Chinese college students (Mage = 18.89, SDage = 2.02, 57.7% male) from three universities completed a questionnaire assessing personal values, internalizing problems, externalizing problems, substance disorders, crime/violence, and life satisfaction. The latent profile analysis identified five personal value profiles, which were labelled as traditional social orientation, open personal orientation, open social orientation, moderate traditional social orientation, and average. Chinese college students in the three social orientation profiles reported low mental health disorders and high life satisfaction. In contrast, students in the personal orientation profile reported high mental health disorders and low life satisfaction. The results indicate the heterogeneity of Chinese college students' personal values and the positive relationship of social-oriented values with mental health and life satisfaction in collectivist cultures. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the diagnostic accuracy of computed tomography pulmonary angiography (CTPA) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for pulmonary artery (PA) masses. Methods: Of 2889 patients with PA filling defects of PA on CTPA, 79 consecutive patients suspicious for PA malignancy who subsequently underwent 18F-FDG PET/CT were enrolled. All masses were diagnosed on the basis of pathological findings or clinical imaging follow-up. For each mass, morphological CT signs, standardized uptake value (SUVmax and SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on 18F-FDG PET/CT were used as diagnostic markers. Results: Expansive growth, irregular margin, invasion, CT contrast uptake, and wall eclipse sign were strongly associated with the malignant nature of masses. The coexistence of at least 5 CT signs perfectly identified malignant masses, whereas the detection of no more than 4 CT signs did not accurately discriminate between the natures of masses. Mean SUVmax, SUVmean, MTV, and TLG values were significantly higher in malignant masses compared to those in benign masses. The diagnostic accuracy of 18F-FDG PET/CT parameters (SUV, MTV, and TLG) was excellent in detecting malignant masses. Among patients with 3 or 4 pathological CT signs, SUVmax > 3.4 significantly increased the identification of malignancies. Conclusions: CTPA is a useful imaging modality for diagnosing PA masses, especially when at least 5 abnormal CT signs are identified. Similarly, 18F-FDG PET/CT accurately identified malignant masses and provided additional valuable information on diagnostic uncertainties after CTPA. [ABSTRACT FROM AUTHOR]

The upregulation of immune and inflammatory response may play a role in the negative symptoms of schizophrenia. Berberine is an effective drug with anti-inflammatory property, and may be beneficial for the treatment of negative symptoms. The aim of this study is to test this hypothesis through a randomized, double-blind, placebo-controlled, clinical trial. Eligible patients with schizophrenia were randomized to receive placebo or berberine (900 mg/day) for 8 weeks as adjunctive treatment to single atypical antipsychotic drug. The Positive and Negative Syndrome Scale (PANSS) was used to evaluate clinical symptoms at three time points (baseline, 4th and 8th week). Blood samples were collected at the above three time points to determine the concentrations of inflammatory markers including interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP). 59 patients with intention-to-treat were analyzed, 32 in the berberine group and 27 in the placebo group. From the baseline to the 8th week, berberine treatment significantly improved the negative symptom subscale of PANSS (F = 18.981; p < 0.001). From the baseline to the 8th week, the plasma CRP concentration decreased in the berberine group, while increased in the placebo group (F = 5.373; p = 0.024). Furthermore, in the berberine group, the change of CRP concentration was significantly positively correlated with the change of PANSS negative symptom subscale within 8 weeks (r = 0.56; p = 0.002). There was no significant difference in adverse events between the two groups (p's > 0.05). Our study suggests that berberine treatment is well tolerated in patients with schizophrenia. Berberine may improve negative symptoms through anti-inflammatory effect. Trial registration: Clinicaltrials.gov identifier: NCT 03548155. [ABSTRACT FROM AUTHOR]

As an ideal substitute for traditional organic fluorescent dyes or up-conversion nanomaterials, copper nanoclusters (CuNCs) have developed rapidly and have been involved in exciting achievements in versatile applications. The emergence of novel CuNCs composites improves the poor stability and fluorescence intensity of CuNCs. With this in mind, great efforts have been made to develop a wide variety of CuNCs composites, and impressive progress has been made in the past few years. In this review, we systematically summarize absorption, fluorescence, electrochemiluminescence, and catalytic properties and focus on the multiple factors that affect the fluorescence properties of CuNCs. The fluorescence properties of CuNCs are discussed from the point of view of core size, surface ligands, self-assembly, metal defects, pH, solvent, ions, metal doping, and confinement effect. Especially, we illustrate the research progress and representative applications of CuNCs composites in bio-related fields, which have received considerable interests in the past years. Additionally, the sensing mechanism of CuNCs composites is highlighted. Finally, we summarize current challenges and look forward to the future development of CuNCs composites. Schematic diagram of the categories, possible sensing mechanisms, and bio-related applications of copper nanoclusters composites. [ABSTRACT FROM AUTHOR]

In order to study the ecological suitability evaluation of urban construction land, based on GIS and RS technology, this paper uses Delphi method to determine the natural, socio-economic, and ecological security factors that affect the ecological suitability of urban construction land and uses AHP to calculate the weight of the relevant factors. The results show that the superposition values are divided into five categories by K-means clustering. In conclusion, according to the principle of ecological protection priority, a set of evaluation model system and method of ecological suitability of urban construction land is established, and the basic ecological control area of the study area is divided according to the principle of ecological protection priority, so as to provide suggestions for reasonable and effective planning of urban land resources. [ABSTRACT FROM AUTHOR]

Asthma is a chronic and genetically complex respiratory disease that affects over 300 million people worldwide. Here, we report a genome-wide analysis for asthma using data from the UK Biobank and the Trans-National Asthma Genetic Consortium. We identify 66 previously unknown asthma loci and demonstrate that the susceptibility alleles in these regions are, either individually or as a function of cumulative genetic burden, associated with risk to a greater extent in men than women. Bioinformatics analyses prioritize candidate causal genes at 52 loci, including CD52, and demonstrate that asthma-associated variants are enriched in regions of open chromatin in immune cells. Lastly, we show that a murine anti-CD52 antibody mimics the immune cell-depleting effects of a clinically used human anti-CD52 antibody and reduces allergen-induced airway hyperreactivity in mice. These results further elucidate the genetic architecture of asthma and provide important insight into the immunological and sex-specific relevance of asthma-associated risk variants. Asthma is a common disease of the airways for which numerous genetic loci have been identified. Here, Han et al. carry out a genome-wide analysis for asthma to identify additional loci, report sex-stratified and genetic risk score analyses, and functionally follow-up one locus using a murine model of airway hyperreactivity. [ABSTRACT FROM AUTHOR]

A hybrid monolith was prepared from perovskite and cucurbit[6]uril [poly(hydroxyethyl methacrylate-pentaerythritol triacrylate) monolith] for the enrichment of phosphopeptides. By coupling with mass spectrometry, three goals were simultaneously realized, viz. (a) selective enrichment of phosphopeptides from non-phosphopeptides, (b) identification of mono- and multi-phosphopeptides, and (c) recognition of tyrosine phosphopeptides. The perovskite introduced into the monolith warrants high selectivity for phosphopeptides even at a high (10,000:1) ratio of non-phosphopeptides to phosphopeptides, and and enables identification of eight mono- and multi-phosphopeptides from standard β-casein tryptic digests. Tyrosine phosphopeptides were specifically detected via the recognition capability of cucurbit[6]uril integrated into the monolith. The method has remarkably specific enrichment capacity for phosphopeptides from samples including human serum, nonfat milk, and human acute myelocytic leukemia cell lysate. [ABSTRACT FROM AUTHOR]

Melanoma is an aggressive cancer with increasing incidence and a growing lifetime risk that arises from normal melanocytes or their precursors. A thorough understanding of the molecular mechanism of melanomagenesis and melanoma biology is essential for the diagnosis, prognostication, and therapy of melanoma. Cyclin-dependent protein kinase 5 (Cdk5) is one of the proteins highly expressed in B16-F10 melanoma cells that controls melanoma cell motility, invasiveness, and metastatic spread and might be a promising novel therapeutic target. The effect of Cdk5 on proliferation and migration, which are important for carcinogenesis, has not been reported. In the current study, we found that siRNA-mediated knockdown of Cdk5 in B16-F10 melanoma cells inhibited melanoma cell proliferation through downregulation of the CaMK4-p-CREB pathway, inhibited migration through downregulation of p-CREB, integrin beta 1, and integrin beta 5, and also inhibited tyrosinase activity and melanin production through p-CREB-MITF regulation. The results indicate that Cdk5 controls melanoma development, with an essential regulatory role for p-CREB. [ABSTRACT FROM AUTHOR]

In this work, poly(glycidyl methacrylate-ethyleneglycol dimethacrylate) monolith functionalized with copper tetra(N-carbonylacrylic) aminephthalocyanine and iminodiacetic acid was successfully synthesized. Owing to hydrogen bonding and hydrophilic interactions, the monolith exhibited good performance for glycopeptide enrichment. When the tryptic digests of horseradish peroxidase were enriched by the developed monolith, a total of 20 glycopeptides could be captured and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis with a detection limit as low as 0.5 fmol μL−1. With the mixture of bovine serum albumin and horseradish peroxidase digests (200:1, m/m) as the sample, 14 glycopeptides were identified after enrichment, showing the high selectivity of the monolith. Moreover, the functionalized monolith exhibited good stability and reproducibility. It was successfully applied to enrich glycopeptides from human serum, demonstrating its potential applications in selective and efficient capture of glycopeptides in complex biological samples.ᅟ [ABSTRACT FROM AUTHOR]

The Chan-Lam reaction was applied to the preparation of a porous aromatic framework (PAF) at room temperature in air without employing expensive noble metal catalysts. The PAF is shown to be a viable sorbent for use in solid-phase microextraction of antioxidants and preservatives as contained in cosmetics. The material was characterized by FT-IR, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. Effects of various experimental parameters on the extraction efficiency were investigated. The analytes were extracted by using a fiber coated with the PAF. Following extraction, the fiber was directly inserted into a GC analyzer with flame ionization detection. Specifically, the following antioxidants and preservatives were extracted and detected: 2- tert-butyl-4-methoxyphenol (BHA), 2,6-bis(1,1-dimethylethyl)-4-methylphenol (BHT), methylparaben (MP), and propylparaben (PP). Under the optimum experimental conditions, the method has a low limit of detection (0.12-0.22 μg L for antioxidants and 0.19-0.30 μg L for preservatives) and a linear response in the 0.02 to 500 mg L for concentration range. Relatives standard deviations (RSDs) for one fiber ranged from 1.2% to 7.2% ( n = 6) while those for three different fibers ( n = 3) were in the range between 4.3% and 11.0%. The fiber was successfully employed to the determination of antioxidants and preservatives in cosmetic samples with recoveries of 81.5%-110.2%. [ABSTRACT FROM AUTHOR]

The authors describe a hybrid of magnetic task-specific poly(ionic liquid) containing dual task-specific sites in an approach to both preconcentrate and quantify gold(III), palladium(II) and platinum(IV). The hybrid was obtained by successive alkaline coprecipitation, sol-gel, quaternization, elimination, anion exchange and polymerization. The material was characterized by scanning electron microscopy, transmission electron microscopy, FTIR spectroscopy, thermal gravimetric analysis, X-ray photoelectron spectrometry, X-ray diffractometry, and vibrating sample magnetometry. It was applied as an effective sorbent for magnetic solid-phase extraction of gold(III), palladium(II) and platinum(IV) ions. The effects of sample pH, amount of adsorbent, extraction time, eluent concentration and volume were optimized. Following elution with a thiourea/HCl solution, the ions were quantified by graphite furnace AAS. The calibration plot is linear in the 50 to 350 ng·L gold(III) concentration range, in the 50 to 650 ng·L palladium(II) concentration range, and in the 150 to 2100 ng L platinum(IV), respectively. Other figures of merit for noble metals determination, respective, include (a) detection limits of at 19.7, 22.3 and 107.0 ng·L, (b) enrichment factors of 197, 174 and 168; and (c) reproducibilities (expressed as relative standard deviations) of 2.1%, 1.4% and 1.5%. In our perception, the method excels by its high sensitivity and preconcentration capability. It was successfully applied to the determination of gold(III), palladium(II) and platinum(IV) in certified reference materials and (spiked) real samples. [ABSTRACT FROM AUTHOR]

With train speed increasing, the heat generation from its key equipment is growing as well and the cooling and ventilation of the equipment cabin become more and more important. In this paper, computational fluid dynamics (CFD) method is adopted to simulate the airflow and the temperature field in indoor and outdoor space of the equipment cabin when the train moves at 250 km/h in open space. The simulation results indicate that the surface temperature of the main heat generation equipment is not beyond the limit. When the train moves forward and backward, the maximum average surface temperature of the heat generation equipment is 56.5 °C and 71.7 °C, respectively, and the airflow rates of the fans in the equipment cabin are decreased by 9.1% and 5.2%, if compared to the rated value, respectively. Both forward and backward running conditions should be considered when designing the layout of the equipment and grilles. It is suggested that, the major heat generation equipment should be located in the middle of the cabin; the flow rate decrement of the cooling fan when the train moves at 250 km/h should be taken into account. [ABSTRACT FROM AUTHOR]

An organic-inorganic composite, γ-alumina nanoparticle modified polyacrylamide, was synthesized in this study. The composite was characterized by scanning electron microscope, nitrogen adsorption-desorption measurement, thermal gravimetric analyzer, differential scanning calorimetry, and Fourier-transformed infrared spectrometer. A novel solid-phase extraction method with the synthesized composite as the adsorbent was developed for the enrichment of Sunset Yellow coupled with ultraviolet-visible spectrophotometry. To obtain the optimum extraction efficiency, the experimental parameters in the processes of preparation of the adsorbent and solid-phase extraction were studied including synthesis temperature, synthesis time, the dosage of γ-alumina nanoparticles, sample flow rate, sample pH, eluant concentration, and eluant flow rate. Under the optimum conditions, the detection limit of the developed method was calculated to be 0.037 μg mL with intra-day and inter-day relative standard deviation values of 2.57% and 3.89%, respectively. When the method was applied to the determination of Sunset Yellow in beverages, satisfactory recoveries were obtained in the range of 92.3-109.8%. [ABSTRACT FROM AUTHOR]

We show that graphene oxide functionalized with 3-aminophenylboronic acid represents a useful new adsorbent for the selective enrichment of the nucleosides, adenosine, guanosine, uridine, and inosine, which then were quantified by capillary electrophoresis. The analytes were separated within 10 min using a borate buffer of pH 9.3 (containing sodium dodecyl sulfate) at an operating voltage of 25 kV, a temperature of 20 °C, a sample injection time of 5 s, and with UV detection at 254 nm. The effects of sample pH, sample flow rate, eluent type, and eluent flow rate were optimized. Under the optimized conditions, the enrichment factor was determined to be 10. A linear relationship was obtained over the 0.1 to 100 μg mL concentration range, with regression coefficients of >0.9991. The intra-day and inter-day relative standard deviations of this method were in the range of 3.1-5.0 % and 4.8-7.5 %, respectively. The method was applied to the determination of the nucleosides in (spiked) traditional Chinese medicine injection samples, and recoveries ranged from 70.8 to 106.7 %. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We developed a methodology based on cloud point extraction (CPE) for the determination of three nitroanilines, p-nitroaniline (PNAL), m-nitroaniline (MNAL), and o-nitroaniline (ONAL). The CPE methodology was coupled with high performance liquid chromatography determinations. Tergitol 15-S-7, an environmentally friendly nonionic surfactant, was employed as the surfactant. To obtain the optimum extraction efficiency, several experimental factors were investigated, including sample pH, salt concentration, surfactant concentration, equilibration temperature, and incubation time. Under the optimized experimental conditions, the linear ranges were 0.06-1, 0.03-1, and 0.01-1 μg mL for PNAL, MNAL, and ONAL, respectively. The limits of detection (LOD) for PNAL, MNAL, and ONAL were 0.013, 0.005, and 0.002 μg mL with the intraday and interday relative standard deviations less than 3.1% and 6.5%. The present method proved to be simple, green, rapid, sensitive, and competitive when used for the determination of nitroanilines in water samples, and the accuracy was assessed through recovery experiments. [ABSTRACT FROM AUTHOR]

We report on the use of a water-insoluble pillar[5]arene derivative carrying ten carboxy groups as an adsorbent, packed in a glass microcolumn, for the separation and preconcentration of trace gold (Au) and palladium (Pd). Sample pH, sample loading time, sample flow rate, eluent concentration, and eluent flow rate were optimized. Effects of potentially interfering metal ions that are commonly encountered in soil were also investigated. Under the optimized conditions, the enrichment factors for Au and Pd are 12 and 16, respectively. Flow injection in combination with flame atomic absorption spectrometry was then applied for the quantitation of the elements. The analytical range is linear in the range between 0.05 and 1 μg mL for both Au and Pd. The limits of detection are 15.9 μg L for Au and 16.0 μg L for Pd, with relative standard deviations (for n = 11) of 0.7 % (Au) and 0.4 % (Pd), respectively. The accuracy of the method was validated using certified reference materials (coal and ash) and geological samples. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate whether hemodiafiltration combined with resin-mediated absorption is a better therapy for hyperlipidemic acute pancreatitis. Patients ( n = 67) with acute pancreatitis treated in ICU from January 2009 to December 2012 were included in this study. Seven of these 67 cases were diagnosed hyperlipidemic acute pancreatitis (HLAP). All the 7 HLAP patients went through fast, gastrointestinal decompression, anti-shock treatment, inhibition of pancreatic secretion, antiseptic treatments, and hemoperfusion (HP) combined with continuous veno venous hemodiafiltration (CVVHDF). After one round of treatment by resin adsorption, there was a significant decrease in serum triglycerides (TG) (29.78 %) and total cholesterol (TC) (24.02 %) levels ( p < 0.01). TG and TC levels dropped by 49.02 and 37.66 %, respectively, after 1-day treatment of HP + CVVHDF; by 62.81 and 47.37 % on day 2 post-treatment; and by 69.57 and 49.47 % on day 3 post-treatment. All the 7 patients survived. The average time spent in the ICU was 7 ± 3.8 days, and the average duration of hospitalization was 19 ± 15.1 days. Our results show that hemoperfusion combined with hemodiafiltration is an efficient treatment as this approach can reduce plasma lipid levels effectively and reduce the risk of acute pancreatitis due to hyperlipidemia. [ABSTRACT FROM AUTHOR]

We sought to study the clinical efficacy of various combined blood purification techniques in patients with non-viral acute liver failure complicated by multiple organ dysfunction syndrome (MODS). For this purpose, 19 patients diagnosed of mid- or late-stage liver failure with MODS score-4 were randomly divided into 3 treatment groups of PE+HP+CVVHDF, PE+CVVHDF, and HP+CVVHDF, respectively. Pre- and post-treatment heart rate (HR), mean arterial pressure (MAP), arterial blood gases (pH, PaO, and PaCO), hepatic function, platelet count, and blood coagulation were determined. The data show significant improvement in HR, MAP, PaO/FiO, total bilirubin (TBIL), and alanine aminotransferase (ALT) levels after treatment ( P < 0.05). TBIL decreased more significantly after treatment in PE+CVVHDF and PE+HP+CVVHDF groups ( P < 0.01). Significant improvement in prothrombin time and albumin was observed only in PE+CVVHDF and PE+HP+CVVHDF groups ( P < 0.05). The decrease of TBIL and improvement of PaO/FiO ratio were more pronounced in PE+HP+CVVHDF than in HP+CVVHDF group ( P < 0.05). To conclude, liver function was relatively improved by all the three combined blood purification techniques used; however, PE+HP+CVVHDF approach was found more efficient in the removal of toxic metabolites, especially bilirubin. The data suggest that the combined blood purification techniques used were effective and involved minor side effects. [ABSTRACT FROM AUTHOR]

The field of separation science has recently witnessed an explosion of interest and progress in the design and study of porous polymer monolithic materials. Monolithic columns with their unique structure possess some exceptional characteristics, which make them an excellent tool in the hands of analytical chemists, not only for separation but also for sample pretreatment. As a new member of the polymer monolith family, the micro/nanomaterial-functionalized polymer monolith has attracted considerable attention due to its many distinct characteristics, such as high permeability and selectively tailored surface chemistries. It exhibits great potential in separation science and analytical sample preparation. This review summarizes and highlights recent major advances of the micro/nanomaterial-functionalized polymer monolith, focusing on design considerations and the application of separation and enrichment. A brief overview of the properties of polymer monolithic columns is included, and then specific attention is paid to discuss the methods of fabrication and application of the micro/nanomaterial-functionalized polymer monolith in separation, sample pretreatment and enrichment, and highly sensitive detection. Finally, future possible research directions and challenges in the field are discussed. [ABSTRACT FROM AUTHOR]

In this paper, an improved particle swarm optimization (PSO) algorithm is proposed for the resource-constrained project scheduling problem (RCPSP) which is widely applied in advanced manufacturing, production planning, and project management. The algorithm treats the solutions of RCPSP as particle swarms and employs a double justification skill and a move operator for the particles, in association with rank-priority-based representation, greedy random search, and serial scheduling scheme, to execute the intelligent updating process of the swarms to search for better solutions. The integration combines and overhauls the characteristics of both PSO and RCPSP, resulting in enhanced performance. The computational experiments are subsequently conducted to set the adequate parameters and compare the proposed algorithm with other approaches. The results suggest that the proposed PSO algorithm augments the performance by 9.26, 16.17, and 10.45 % for the J30, J60, and J120 instances against the best lower bound-based PSO currently available, respectively. Moreover, the proposed algorithms demonstrate obvious advantage over other proposals in exploring solutions for large-scale RCPSP problems such as the J60 and J120 instances. [ABSTRACT FROM AUTHOR]

A simple and sensitive method based on polymer monolith microextraction (PMME) using a poly(methacrylic acid-co-ethylene glycol dimethacrylate) (poly(MAA-EGDMA)) monolith has been developed for the determination of triazines combined with high-performance liquid chromatography. The method is evaluated with several parameters including linear range, limits of detection, limits of quantification, and reproducibility after optimizing PMME experimental conditions. Sample flow rate, sample volume, eluent flow rate, and sample pH have been investigated and optimized in detail with respect to extraction efficiency of the target compounds from cereal samples. Good linearities are obtained for six triazines with the correlation coefficients ( R) above 0.9977. Limits of detection based on three times of standard deviations of blank by seven replicates are in the range of 1.1−2.8 μg kg. Good reproducibility of the method is obtained, yielding the intra-day and inter-day relative standard deviations less than 4.3% and 5.5%, respectively. The method has been proved to be efficient, fast, and sensitive for the quantitative analysis of triazines in practical cereal samples. [ABSTRACT FROM AUTHOR]

We have prepared an environmental friendly sorbent by modifying multi-walled carbon nanotubes with tannic acid. The adsorption of La (III), Tb (III) and Lu (III) as a function of contact time, initial solution pH, and quantity of adsorbent was studied using a batch technique. Both Langmuir and Freundlich isotherms can be used to describe the process. The major adsorption mechanisms were attributed to ion exchange and surface complexation. The kinetics of the adsorption follows a pseudo-second-order model. The thermodynamic functions Δ H, Δ G, and Δ S indicate that the sorption is endothermically driven. The adsorbed ions can be readily desorbed from the surface with 1 M hydrochloric acid. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In the present study, sec-nonylphenoxy acetic acid (CA100) and its mixtures with four neutral organophosphorus extractants, tri-butyl-phosphate (TBP), 2-ethylhexyl phosphonic acid di-2-ethyl ester (DEHEHP), Cyanex923, and Cyanex925 have been applied to the extraction of rare earths. Results show that all the four mixing systems do not have evident synergistic effects on the extraction of rare earths. The different extraction effects have been considered to the separation of rare earths. The four mixtures may be applied to the separation of yttrium from some certain lanthanoids at proper mole fractions of CA100. [ABSTRACT FROM AUTHOR]

simple, cheap, and nonpolluting method was developed for the cloud point extraction of gold (Au) and palladium (Pd). It is based on the complexation reaction of Au and Pd with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) and micelle mediated extraction of the complex using the non-ionic surfactant poly(ethylene glycol) mono- p-nonylphenyl ether (PONPE 7.5). Under the optimized experimental conditions, the enrichment factors are 16 and 17 for Au and Pd, respectively, for 15 mL of preconcentrated solution. The limits of detection are 3.8 μg L and 1.8 μg L for Au and Pd, respectively. The relative standard deviations are 1.4% for Au and 0.6% for Pd ( n = 11). The method was successfully applied to the determination of Au and Pd in certified reference materials and mine samples. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The extraction of rare earths from nitrate medium using three organophosphorus acids, 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (HEHEHP), di-(2-ethylhexyl) phosphoric acid (D2EHPA), bis(2,4,4-trimethylpentyl) phosphinic acid (Cyanex272), and their mixtures with sec-octylphenoxy acetic acid (CA12) has been studied in detail. The mixtures have different extraction effects on various rare earths. Synergistic extraction effects are only found when light rare earths and yttrium (III) are extracted with mixtures of D2EHPA and CA12. The possibilities of separating the rare earths with these mixtures are investigated according to the extractabilities. It is feasible and advantageous to separate yttrium (III) from the lanthanoids (III) with HEHEHP + CA12 and D2EHPA+CA12 mixtures at proper extractant ratios. The separation of yttrium (III) from heavy rare earths is also possible with mixtures of Cyanex272 and CA12. [ABSTRACT FROM AUTHOR]

In the present study, a synergistic extraction mixture, primary amine N1923 (RNH2) and Cyanex925 (B), was loaded on PTFE powder to prepare PTFE Selective Resin and was employed for the adsorption of zinc, cadmium, and copper from chloride medium. The effects of shaking time, resin amounts, concentration of metal ions, and experimental temperature on the distribution coefficients were determined. The stoichiometry of the adsorbed complexes was determined to be MCl2·(1/2)RNH2·B with the Selective Resin. The equilibrium constants and thermodynamic quantities (ΔH, ΔG, and ΔS) were calculated. Furthermore, the Freundlich isotherm proved to be more suitable than the Langmuir isotherm to indicate the effect of concentration of M2+ on the adsorption with PTFE Selective Resin. [ABSTRACT FROM AUTHOR]

A rapid and reliable method based on micellar electrokinetic capillary chromatography has been developed for the determination of dexamethasone in cosmetics. Effects of buffer composition, concentration and pH, the detection wavelength, separation voltage, and injection time were systematically investigated. The optimum conditions were: 30 mM borax buffer containing 20 mM sodium dodecyl sulfate at pH 9.0, detection at 254 nm, injection time 10 s at a height of 10 cm, and a separation voltage of 15 kV. Under these conditions, the analysis of dexamethasone in cosmetics was carried out within 6 min. The method was validated for stability, precision, linearity and accuracy. Excellent linearity was obtained in the range of 50–1,000 μg mL−1, and acceptable precision, in intra-day and inter-day analysis, was also obtained with relative standard deviation in the range of 0.19–0.86 and 2.50–4.90% for migration time and peak area ratio, respectively. The method was used to analyse eight cosmetic samples purchased locally. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the usefulness of the limited fluid resuscitation regimen combined with blood pressure-controlling drugs in treating acute upper gastrointestinal hemorrhage concomitant with hemorrhagic shock. A total of 51 patients were enrolled and divided into a group that received traditional fluid resuscitation group (conventional group, 24 patients) and a limited fluid resuscitation group (study group, 27 patients). Before and after resuscitation, the blood lactate, base excess, and hemoglobin values, as well as the volume of fluid resuscitation and resuscitation time were examined. Compared with conventional group, study group had significantly better values of blood lactate, base excess, and hemoglobin (all p < 0.05). In addition, both volume of fluid resuscitation and resuscitation time were significantly ( p < 0.05) lower in these patients. Limited fluid resuscitation combined with blood pressure-controlling drugs effectivelyxxx maintains blood perfusion of vital organs, improves whole body perfusion indicators, reduces the volume of fluid resuscitation, and achieves better bleeding control and resuscitation effectiveness. [ABSTRACT FROM AUTHOR]

The design and preparation of magnetic cucurbit[6]uril hypercrosslinked with polymers are described. The materials have a large specific surface, abundant mesopores and cavities, and display superparamagnetism. They were applied to the enrichment of ubiquitinated peptides from standard protein digests. Following desorption with 0.15% TFA, the peptides were quantified by MALDI-TOF MS. The method has a detection limit of 2 fmol·μL−1 and a mass ratio selectivity of 1:5000 as shown for ubiquitin and bovine serum albumin. The materials enable selective capture of ubiquitinated peptides from genuine samples comprising of oyster mushroom and human serum. This demonstrates their potential for the analysis of low-level ubiquitin in complex samples. [ABSTRACT FROM AUTHOR]

An electrostatically controlled fluorometric assay is described that is based on the use of silver/copper bimetallic nanoclusters. The nanoclusters were coated with polyethyleneimine (PEI-Ag/CuNCs). At pH 7.4, these particles are positively charged. Their blue fluorescence (with excitation/emission peaks at 341/464 nm) depends on local pH values and temperature. If graphene oxide (which is negatively charged at pH 7.4) is introduced, the fluorescence of the PEI-Ag/CuNCs is quenched. Based on various electrostatic interactions, three kinds of biomacromolecules were detected by fluorometry. These include (negatively charged) heparin, (positively charged) protamine, and (virtually uncharged) trypsin. Heparin is detected by using GO/PEI-Ag/CuNCs, protamine by using GO/heparin/PEI-Ag/CuNCs, and trypsin by using GO/protamine/heparin/PEI-Ag/CuNC. The detection limits and linear ranges are 4.8 nM and 10-450 nM for heparin, 0.09 μg·mL−1 and 0.25-5 μg·mL−1 for protamine, and 0.03 μg·mL−1 and 0.05-1 μg·mL−1 for trypsin. Zeta potentials of the various substances in the system were determined to elucidate the detection mechanism. Comceivably, the method provides a widely applicable approach for electrostatically controlled biomolecular assays.Schematic presentation of electrostatically controlled fluorometric assay for the detection of heparin, protamine, and trypsin based on the silver/copper bimetallic nanoclusters modified with polyethyleneimine and graphene oxide. [ABSTRACT FROM AUTHOR]

A dual-pore covalent organic framework (COF) that contains micropores and mesopores was prepared from 2,4,6-triphenoxy-1,3,5-triazine (TPT). A building block is used in which double linking sites were introduced at each branch of a C3-symmetric skeleton. The COF is shown to be a viable coating for fibers for solid-phase microextraction of phthalic acid esters (PAEs). Its high specific surface, high hydrophobicity, and wide pore size distribution of a TPT-COF coated fiber result in extraordinarily powerful extraction of PAEs. The enrichment factor is up to 7790 under optimum conditions. The method has detection limits that range between 5 and 95 ng L−1. The inter-batch relative standard deviations are between 3.1 and 10.9%, and those for intra-batch assays are from 0.8 to 4.7%. The TPT-COF coated fibers were applied to the extraction of PAEs from (spiked) juice samples, and satisfactory recoveries were achieved.TPT-COF coated SPME fiber was prepared for the preconcentration of phthalate esters coupled with GC-FID. [ABSTRACT FROM AUTHOR]