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A novel multifunctional silica magnetic molecularly imprinted polymer (MQDs-MIPs) nanoparticle probe was synthesized for the rapid detection of triflumuron (TFM). The fluorescence probe consists of magnetite (Fe3O4) as a core and is wrapped with a molecularly imprinted polymer doped with Mn-doped ZnS quantum dots (QDs). Under optimal detection condition, the fluorescence quenching efficiency of MIP@Fe3O4@ZnS:Mn QDs displayed a linear relationship over the concentration range of 0–27.88 μmol/L with a correlation coefficient of 0.9947. Four structurally similar compounds were selected for selectivity testing and the nanocomposite showed good selectivity with a higher imprint factor of 2.52. This developed method has the advantages of simple preparation, fast response and low toxicity for trace TFM detection. [ABSTRACT FROM AUTHOR]

Tunnel failure caused due to geologic heterogeneity and variability in both mining processes and tunnel arrangement in deep metal mines is very complex. In this paper, a quantitative risk assessment for deep tunnel failure was conducted using clustering and logistic regression. The study was performed by considering various representative evaluation indexes of geological conditions, mining disturbance, and microseismic (MS) data. Comprehensive Seismic Event Clustering (CSEC) methodology was used to analyse the MS data to filter noise data and identify seismic sources. Additionally, peak particle velocity (PPV) was used to quantitatively evaluate the influence of MS activities on the response of tunnel which would aid in determining the PPV distribution characteristics of a large regional tunnel. Furthermore, Excavation Vulnerability Potential (EVP) index was used to quantitatively evaluate the effect of site conditions on response of the tunnel. Thus, based on logistic regression, PPV and EVP were used to establish a risk assessment model to determine the tunnel damage levels and probability of damage occurrence. The successful application of the proposed method at the Ashele copper mine demonstrates that it is capable of conducting a risk assessment for tunnel failure in deep metal mines. [ABSTRACT FROM AUTHOR]

Background: Stone recurrence is a major problem limiting the effects of surgical treatment for hepatolithiasis. It was showed that hyperplasia of perihilar liver may compress the hepatic portal and cause deficient bile flow because of compressed hilar bile duct, thereby leading to the formation of bile stasis and precipitating stone recurrence. This retrospective study aimed to evaluate the efficiency of perihilar hepatectomy for hepatolithiasis with compressed hilar bile duct induced by perihilar hyperplasia of liver. Methods: 135 patients with compressed hilar bile duct induced by hypertrophied perihilar liver were included in this study from January 2011 to July 2016. Among these patients, 77 underwent conventional operation procedure (control group) and 58 underwent conventional operation procedure added by perihilar hepatectomy (perihilar hepatectomy group). Clinical data containing preoperative data, intraoperative data, operation complications, and short-term and long-term outcomes were collected. Results: The demographic and disease-related characteristics of the two groups were comparable. The two groups were not remarkably different in operationrelated characteristics. The incidence of bile leakage in the perihilar hepatectomy group was substantially higher than that in the control group. Other postoperative complications were not remarkably different between the two groups. In the long-term postoperative follow-up period, the incidence of the recurrence of stones and cholangitis in the control group was considerably higher than that in the perihilar hepatectomy group. Conclusions: Based on conventional operation procedure, additional perihilar hepatectomy is a reliable intervention with definite clinical effects for hepatolithiasis with compressed hilar bile duct induced by hypertrophied perihilar liver. [ABSTRACT FROM AUTHOR]

In order to improve thermal and humid environment of the heat hazard mine, a ground cooling system is proposed. In the ground cooling system, the chilled water is transmitted to the air cooler in working face through long-distance vertical-buried pipes (LDVBP). Under this background, the simplified numerical heat transfer model between LDVBP and rock-soil layers is established to calculate the temperature rise and heat loss of the chilled water. Comparing the calculated results with the measured data in Wutongzhuang Coal Mine of Hebei province, the error is less than 5%. Furthermore, the numerical simulation results show the main influencing factors on heat loss of LDVBP are the heat transfer temperature difference of underground high- and low-pressure heat exchanger, flow rate, and inlet temperature of supply water when there is no groundwater seepage, which should be considered in ground cooling system design. In this study, the supply water temperature rise is 0.15°C and the comprehensive heat loss coefficient is less than 5.8%, which can meet the requirements of mine cooling engineering. [ABSTRACT FROM AUTHOR]

Tamarind nut powder (TNP) from kitchen waste of tamarind nuts was modified with in situ generated copper nanoparticles (CuNPs) using hydrothermal method. The modified TNP had spherical CuNPs with an average size of 84 nm. The thermal stability of the modified TNP was lower than that of the TNP due to the catalytic activity of the in situ generated CuNPs in lowering the thermal stability. Further, it exhibited significant antibacterial activity against both the Gram negative and Gram positive bacteria and hence can be used as low-cost filler to prepare antibacterial hybrid polymer nanocomposites for packaging and medical applications. [ABSTRACT FROM AUTHOR]

The Shule River Basin is an ecologically fragile area in arid zone. To understand the state of land eco-security, the Environment-Economic-Society model was applied to build a land eco-security evaluation index system in the Shule River Basin. An entropy-weighted and matter-element model was built for eco-security evaluation from 2005 to 2014. Principal component analysis was used to quantitatively study the limiting factors of land ecological security. The result showed: the direction of development of the state of land eco-security in the Shule River Basin from 2005 to 2014 was characterized by “unsafe (No4) → safe (No1),” and presented an upward trend. The land eco-security status during 2005–2007 was in the “Unsafe” state and the state changed to “Critical Safe” in 2008–2009, “Safer” in 2010–2011, but “Safe” in 2012–2014. The key factors that affected land eco-security in the Shule River Basin were Per Capita Arable Land, Forest Cover Rate, Per Capita Water Resources, Water Production Modulus, the Tertiary Industry Output Value, and GDP Ratio and Water Consumption. Among them, Forest Cover Rate and Water Production Modulus had the greatest impact, with principal component loads of up to 0.973 and 0.968, respectively. The result of this study is expected to serve as reference and support for the conservation and management of Shule River Basin to ensure sustainable development. [ABSTRACT FROM AUTHOR]

A simple and facile copper-catalyzed synthesis ofβ-ketophosphine oxides via direct oxyphosphorylation of alkynes with H-phosphine oxides and dioxygen has been developed under mild conditions without any base or cocatalyst. A radical reaction pathway for the formation ofβ-ketophosphine oxides is proposed. An18O labeling experiment suggested that the carbonyl oxygen atom ofβ-ketophosphine oxides originated from dioxygen. [ABSTRACT FROM PUBLISHER]

Genetic variations in cytochrome P450 2C9 are known to contribute to interindividual and interethnic variability in response to clinical drugs, but little is known about the genetic variation of CYP2C9 in the Uyghur population.We directly sequenced the whole CYP2C9 gene in 96 unrelated, healthy Uyghur from Xinjiang Uygur Autonomous Region of China and screened for genetic variants in the promoter, exons, introns and 3′-UTR.Thirty five previously reported alleles and six genotypes were detected in this study. The allele frequencies of CYP2C9*1, *2, *11, *12, *29 and *33 were 89.58, 7.81, 0.52, 0.52, 1.04 and 0.52%, respectively. We detected one non-synonymous novel variant at position 329 from Arg to Cys and this mutation is predicted to be intolerant by SIFT.Our results provide basic information about CYP2C9 alleles in Uyghur, which may help to optimize pharmacotherapy effectiveness by providing personalized medicine to this ethnic group. [ABSTRACT FROM PUBLISHER]

1. CYP2C19is a clinically important enzyme and is involved in the metabolism of approximately 10% of drugs used in daily clinical practice. Previous studies mainly focused on Chinese Han populations or other ethnic groups, little is known about Uyghur populations. 2. The present study was designed to determine the genetic basis ofCYP2C19polymorphisms. 3. We used direct sequencing to investigate the promoter, exons and surrounding introns, and 3′-untranslated region of theCYP2C19gene in 96 unrelated healthy Uyghur individuals. 4. A total of 31 differentCYP2C19polymorphisms were identified in the Uyghur population, three of which were novel, including two nonsynonymous variants (57807A > M, Gln279Pro and 19257G > R, Asp262Asn) and one synonymous variants in exon 5 (19184T > Y, Leu237Leu). In addition,CYP2C19*1, *2 and *3 alleles showed frequencies of 83.34%, 14.06% and 2.08%, respectively. 5. This is the first study that systematically screened the polymorphisms of the wholeCYP2C19gene in Uyghur population. Hence, our results provided important information onCYP2C19polymorphisms in Uyghur population and could be helpful for future personalized medicine studies in Uyghur population generally. [ABSTRACT FROM PUBLISHER]

Little is known about polymorphic distribution of pharmacogenes among ethnicities, including the Deng people. In this study, we recruited 100 unrelated, healthy Deng people and genotyped them with respect to 76 different single-nucleotide polymorphisms by the PharmGKB database. Our results first indicated that the polymorphic distribution of pharmacogenes of the Deng people is most similar to CHD, suggesting that Deng people have a closest genetic relationship with CHD. Our data will enrich the database of pharmacogenomics and provide a theoretical basis for safer drug administration and individualized treatment plans, promoting the development of personalized medicine. [ABSTRACT FROM PUBLISHER]

Aglinin A (1) is a mixture of C24-epimeric 20S,24-epoxy-24,25-dihydroxy-3,4-secodammar-4(28)-en-3-oic acid and present in plants of the family Meliaceae. The two epimers of 1 were resolved through an acetonide reaction, and the absolute configurations of two derivatives were deduced by the analysis of their 13C NMR differences induced by γ-gauche or steric effect. Based on it, the 13C NMR assignment of 24R-1 and 24S-1 was also established. [ABSTRACT FROM AUTHOR]

A simple, sensitive, and label-free electrochemical immunosensor has been developed for the measurement of serum thrombomodulin (TM), an endothelial glycoprotein which is associated with the progression and metastasis of tumors. At first, the graphene nanosheets, which were dispersed in Nafion solution, were used to coat the bare gold electrode. Then, silver-silver oxide nanoparticles (Ag-Ag2O NPs) were immobilized on the graphene-modified electrode by a one-step electrochemical deposition method. Lastly, a thrombomodulin antibody (anti-TM) was attached via amido-Ag affinity. This strategy combines graphene/Ag-Ag2O NPs hybrid materials as an immobilization matrix and Ag-Ag2O NPs also as an electrochemical signal indication reagent. The main advantage of this strategy has two important aspects. One is the high stability and unique electronic properties of the graphene nanostructure. The other is the use of Ag-Ag2O NPs as the immobilization matrix and redox probes, thus avoiding the laborious labeling protein operation. Using this strategy, the concentration of TM in the range of 0.1 to 20 ng/mL was detected, with a detection limit of 31.5 pg/mL (at 3σ). The proposed methodology demonstrates that the nanocomposite film composed of graphene and Ag-Ag2O NPs is a potential for biosensor applications. [ABSTRACT FROM PUBLISHER]

A pulsed pumped Yb3+-doped double-cladding fiber (DCF) amplifier is reported, Seeded by a passive mode-locked Yb3+-doped fiber laser, the fiber amplifier can generate 200 W peak-power and 120 ps duration pulses at 100 Hz repetition rate. Because of the pulsed pump approach, the amplified spontaneous emission (ASE) and the spurious lasing between pulses are well avoided. [ABSTRACT FROM AUTHOR]

(CeO)3(AsW9O34)2ċ2H2O12- was synthesized by the reaction of A-AsW9O349- with Ce(IV). The product was well characterized by IR, UV, 183W NMR spectra and elemental analyses. The structure of K5Na4H3[(CeO)3(H2O)2-(AsW9O34)2]ċ11H2O has been solved by X-ray diffraction. The structure comprises a belt of three oxygen atoms alternating with the three cerium atoms encapsulated between two fragments of the trivacant Keggin polyanions A-AsW9O349-. Its structure is similar to that of the analogue phosphorus derivative. The experimental results show that many ligands, [Fe(CN)6]4-, [Fe(CN)6]3-, SO32-, SCN-, etc. can replace the coordinated water molecules in aqueous solution resulting in characteristic colors of the solutions. [ABSTRACT FROM AUTHOR]