bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Remarkably Efficient MnFe2O4‐based Oxidase Nanozyme
Authors: Vernekar Amit A. , Das Tandrila , Ghosh Sourav , Mugesh Govindasamy 
Published: September 2015

AbstractNanomaterials‐based enzyme mimetics (nanozymes) have attracted considerable interest due to their applications in imaging, diagnostics, and therapeutic treatments. Particularly, metal‐oxide nanozymes have been shown to mimic the interesting redox properties and biological activities of metalloenzymes. Here we describe an efficient synthesis of MnFe2O4 nanomaterials and show how the morphology can be controlled by using a simple co‐precipitation method. The nanomaterials prepared by this method exhibit a remarkable oxidase‐like activity. Interestingly, the activity is morphology‐dependent, with nanooctahedra (NOh) exhibiting a catalytic efficiency of 2.21×109 m−1 s−1, the highest activity ever reported for a nanozyme.
Automatic calibration of fundamental diagram for first‐order macroscopic freeway traffic models
Authors: Zhong Renxin , Chen Changjia , Chow Andy H. F. , Pan Tianlu , Yuan Fangfang , He Zhaocheng 
Published: September 2015

SummaryDespite its importance in macroscopic traffic flow modeling, comprehensive method for the calibration of fundamental diagram is very limited. Conventional empirical methods adopt a steady state analysis of the aggregate traffic data collected from measurement devices installed on a particular site without considering the traffic dynamics, which renders the simulation may not be adaptive to the variability of data. Nonetheless, determining the fundamental diagram for each detection site is often infeasible. To remedy these, this study presents an automatic calibration method to estimate the parameters of a fundamental diagram through a dynamic approach. Simulated flow from the cell transmission model is compared against the measured flow wherein an optimization merit is conducted to minimize the discrepancy between model‐generated data and real data. The empirical results prove that the proposed automatic calibration algorithm can significantly improve the accuracy of traffic state estimation by adapting to the variability of traffic data when compared with several existing methods under both recurrent and abnormal traffic conditions. Results also highlight the robustness of the proposed algorithm. The automatic calibration algorithm provides a powerful tool for model calibration when freeways are equipped with sparse detectors, new traffic surveillance systems lack of comprehensive traffic data, or the case that lots of detectors lose their effectiveness for aging systems. Furthermore, the proposed method is useful for off‐line model calibration under abnormal traffic conditions, for example, incident scenarios. Copyright © 2015 John Wiley & Sons, Ltd.
Simplifying sample preparation using fabric phase sorptive extraction technique for the determination of benzodiazepines in blood serum by high‐performance liquid chromatography
Authors: Samanidou Victoria , Kaltzi Ioanna , Kabir Abuzar , Furton Kenneth G. 
Published: September 2015

AbstractFabric phase sorptive extraction (FPSE), a recently introduced novel sample preparation technology, has been evaluated for the extraction of benzodiazepines from human blood serum. FPSE utilizes a flexible fabric surface as the substrate platform for creating sol‐gel hybrid organic‐inorganic sorbent coatings. FPSE media can be introduced directly into the sample containing the target analyte(s), requiring no need for prior sample pretreatment or clean‐up. Benzodiazepines were selected as model analytes because they represent one of the most widely used therapeutic drugs in psychiatry and are also amongst the most frequently encountered drugs in forensic toxicology. The chromatographic separation of target analytes was performed on a LiChroCART‐LiChrospher®100 RP‐18e (5 µm, 250 × 4 mm) analytical column, operated at room temperature. Ternary gradient elution was applied with a mobile phase that consisted of acetonitrile, methanol and ammonium acetate (0.05 M), which was delivered at a flow rate of 1.0 mL/min. Diode array detection was performed with monitoring at 240 nm. FPSE was performed using cellulose fabric extraction media coated with sol‐gel poly(ethylene glycol) (sol‐gel PEG). Absolute recovery values in the equilibrium state for the examined benzodiazepines were found to be 27% for bromazepam, 63% for lorazepam, 42 % for diazepam and 39% for alprazolam. Copyright © 2015 John Wiley & Sons, Ltd.
Development and validation of a liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) method for the quantification of tigecycline in rat brain tissues
Authors: Munyeza Chiedza F. , Shobo Adeola , Baijnath Sooraj , Bratkowska Dominika , Naiker Suhashni , Bester Linda A. , Singh Sanil D. , Maguire Glenn E. M. , Kruger Hendrik G. , Naicker Tricia , Govender Thavendran 
Published: September 2015

AbstractTigecycline (TIG), a derivative of minocycline, is the first in the novel class of glycylcyclines and is currently indicated for the treatment of complicated skin structure and intra‐abdominal infections. A selective, accurate and reversed‐phase high‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) method was developed for the determination of TIG in rat brain tissues. Sample preparation was based on protein precipitation and solid phase extraction using Supel‐Select HLB (30 mg/1 mL) cartridges. The samples were separated on a YMC Triart C18 column (150 mm x 3.0 mm. 3.0 µm) using gradient elution. Positive electrospray ionization (ESI+) was used for the detection mechanism with the multiple reaction monitoring (MRM) mode. The method was validated over the concentration range of 150–1200 ng/mL for rat brain tissue. The precision and accuracy for all brain analyses were within the acceptable limit. The mean extraction recovery in rat brain was 83.6%. This validated method was successfully applied to a pharmacokinetic study in female Sprague Dawley rats, which were given a dose of 25 mg/kg TIG intraperitoneally at various time‐points. Copyright © 2015 John Wiley & Sons, Ltd.
Development and validation of a UHPLC‐MS/MS bioanalytical method to quantify in plasma the analgesic candidate PT‐31 following a preliminary pharmacokinetic study in rats
Authors: Bessegato T. C. , Niehues M. , Buqui G. A. , Lopes N. P. , Pitta I. R. , Galdino S. L. , Dalla Costa T. 
Published: September 2015

AbstractA selective and sensitive UHPLC‐MS/MS bioanalytical method to determine PT‐31, an analgesic drug candidate, in rat plasma was developed and validated. Analyses were performed using a UHPLC‐MS/MS system equipped with an electrospray ionization interface operating in the positive ionization mode using a C18 reversed‐phase column with a mobile phase of water:acetonitrile (68:31, v/v) containing 0.1% acetic acid eluting in a gradient mode with a flow rate of 0.3 mL/min. Plasma samples were deproteinized with cold acetonitrile containing 0.01% TFA (1:2, v/v) and 50 μL of the supernatant were injected into the system. PT‐31 and phenytoin (internal standard) retention times were roughly 1.0 and 1.5 min, respectively. Linear standard curves were plotted for the 0.01–10 µg/mL concentration range, with a coefficient of determination > 0.99. The method's precision was over 88%. Maximum intra‐ and inter‐day relative standard deviations were 14.6% and 11.6%, respectively. Interfering substances were not detected in the chromatogram, indicating that the method was specific. PT‐31 stability was assessed under different temperature and storage settings. The method was used to characterize PT‐31 plasma pharmacokinetics following administration of 5 mg/kg i.v. to Wistar rats. Therefore, the method described is sensitive, linear, precise and specific enough to determine PT‐31 in preclinical pharmacokinetic investigations. Copyright © 2015 John Wiley & Sons, Ltd.
Metformin prevents DMH‐induced colorectal cancer in diabetic rats by reversing the warburg effect
Authors: Jia Yanglei , Ma Zengyi , Liu Xiaofei , Zhou Wenjing , He Shan , Xu Xia , Ren Guijie , Xu Gang , Tian Keli 
Published: September 2015

AbstractEpidemiologic studies have shown that the treatment of diabetics with metformin reduced the risk of cancer‐related mortality. Here, we investigated the chemopreventive effects of metformin on dimethylhydrazine (DMH)‐induced colorectal carcinogenesis in diabetic SD rats following metformin treatment and the effect on Warburg effect involved in this process. Diabetic rat models were induced with high‐fat feeding in combination with a low dose of Streptozotocin (STZ) and then induce colorectal cancer with a low dose of DMH. The formation of colorectal Aberrant crypt foci (ACF) and the incidence, number and size of the tumor were measured. The proliferation indices of colonic tissues were determined through Proliferating cell nuclear antigen (PCNA) immunostaining. Then detect the expression of PK and IDH in colonic tissues using immunohistochemistry and Western blot. The enzyme activities of HK and PDH in colonic tissues were measured. The growth and expression of PK and IDH and activity of HK and PDH in cell lines LoVo and HT‐29 were measured after metformin treatment. The results showed that metformin treatment significantly inhibited the formation of ACF and tumors. The proliferation index of colonic tissues was significantly decreased following metformin treatment. In addition, metformin inhibited cell growth and decreased the imbalance in the expression of the enzymes involved in glycolysis and the TCA cycle. These findings suggested that metformin might produce a synergistic colon cancer‐preventative effect in diabetic patients through the regulation of the enzymes expression involved in glucose metabolism.
Potentially functional polymorphisms in PAK1 are associated with risk of lung cancer in a Chinese population
Authors: Zheng Mingfeng , Liu Jia , Zhu Meng , Yin Rong , Dai Juncheng , Sun Jie , Shen Wei , Ji Yong , Jin Guangfu , Ma Hongxia , Dong Jing , Xu Lin , Hu Zhibin , Shen Hongbing 
Published: September 2015

AbstractP21‐activated kinase 1(PAK1) plays an important role in the regulation of cell morphogenesis, motility, mitosis, and angiogenesis and has been implicated with tumorigenesis and tumor progression. We hypothesized that functional polymorphisms in PAK1 gene may modify the risk of lung cancer. We screened four potentially functional polymorphisms (rs2154754, rs3015993, rs7109645, and rs2844337) in PAK1 gene and evaluated the association between the genetic variants and lung cancer risk in a case–control study including 1341 lung cancer cases and 1982 cancer‐free controls in a Chinese population. We found that variant allele of rs2154754 was significantly associated with a decreased risk of lung cancer (OR = 0.85, 95% CI: 0.77–0.95, P = 0.004), meanwhile the result of rs3015993 was marginal (OR = 0.90, 95%CI: 0.81–1.00, P = 0.044). After multiple comparisons, rs2154754 was still significantly associated with the lung cancer risk (P < 0.0125 for Bonferroni correction). We also detected a significant interaction between rs2154754 genotypes and smoking levels on lung cancer risk (P = 0.042). Combined analysis of these two polymorphisms showed a significant allele‐dosage association between the number of protective alleles and reduced risk of lung cancer (Ptrend = 0.008). These findings indicate that genetic variants in PAK1 gene may contribute to susceptibility to lung cancer in the Chinese population.
Using an informed consent in mammography screening: a randomized trial
Authors: Baena‐Cañada José M. , Rosado‐Varela Petra , Expósito‐Álvarez Inmaculada , González‐Guerrero Macarena , Nieto‐Vera Juan , Benítez‐Rodríguez Encarnación 
Published: September 2015

AbstractSpanish women do not make an informed choice regarding breast cancer screening (BCS). Our aim was to evaluate the impact of receiving information regarding real BCS benefits and risks on knowledge, attitude, decision, feelings, and worries about cancer. Randomized controlled clinical trial of 355 women aged between 45 and 67 years, 177 and 178 assigned to the intervention group (IG) and control group (CG), respectively. After breast screening, women received either Nordic Cochrane Centre information on BCS or standard information. The primary outcome (knowledge) was determined from questionnaire administered at baseline and after a month. Answers were scored from 0 to 10 and scores of 5 or more indicated that women were well informed (had “good knowledge”). Questionnaires regarding attitudes, future screening intentions, and psychosocial impact were also administered. The Chi‐squared and Student's t‐tests were used to compare qualitative and quantitative variables, respectively. Good knowledge was acquired by 32 (18.10%) IG women and 15 (8.40%) CG women (P = 0.008). Mean scores from first to second interview increased from 2.97 (SD 1.16) to 3.43 (SD 1.39) in the CG and from and from 2.96 (SD 1.23) to 3.95 (SD 1.78) (P = 0.002) in the IG. No differences were found in the secondary endpoints. Women receiving information based on the Nordic Cochrane Centre document were better informed. This means of providing information is not very efficacious, nor does it modify attitude, decision, feelings, or worries about cancer.
Ethnic Identity in Emerging Adults in Sub‐Saharan Africa and the USA, and Its Associations with Psychological Well‐Being
Authors: Adams Byron G. , Abubakar Amina , Van de Vijver Fons J. R. , De Bruin Gideon P. , Arasa Josephine , Fomba Emmanuel , Gillath Omri , Hapunda Given , Looh La Joseph , Mazrui Lubna , Murugami Margaret 
Published: September 2015

AbstractEthnic identity as a social dimension of identity is argued to be developmentally important for psychological well‐being. However, the relationships between these constructs are mainly examined in Western contexts, amongst dominant–non‐dominant groups. We investigate ethnic identity across the mainstream group of a prototypical Western society (the USA) and several multi‐ethnic sub‐Saharan African countries (Cameroon, Kenya, South Africa, and Zambia), as well as how it relates to psychological well‐being. A total of 1255 university students (61.8% females, Mage = 20.94 years, SD = 2.97) completed a questionnaire with ethnic identity and psychological well‐being measures. Results indicated that ethnic identity was most salient in two different South African ethnocultural samples and least salient in a mainstream US sample. These results suggest that groups that are more exposed to ethnic strain in multicultural societies tend to have more salient ethnic identities. Furthermore, the underlying structure in the ethnic identity psychological well‐being relationship was similar across groups. Copyright © 2015 John Wiley & Sons, Ltd.
Inhibition of Gli/hedgehog signaling in prostate cancer cells by “cancer bush” Sutherlandia frutescens extract
Authors: Lin Hui , Jackson Glenn A. , Lu Yuan , Drenkhahn Sara K. , Brownstein Korey J. , Starkey Nicholas J. , Lamberson William R. , Fritsche Kevin L. , Mossine Valeri V. , Besch‐Williford Cynthia L. , Folk William R. , Zhang Yong , Lubahn Dennis B. 
Published: September 2015

AbstractSutherlandia frutescens is a medicinal plant, traditionally used to treat various types of human diseases, including cancer. Previous studies of several botanicals link suppression of prostate cancer growth with inhibition of the Gli/hedgehog (Gli/Hh) signaling pathway. Here we hypothesized the anti‐cancer effect of S. frutescens was linked to its inhibition of the Gli/Hh signaling in prostate cancer. We found a dose‐ and time‐dependent growth inhibition in human prostate cancer cells, PC3 and LNCaP, and mouse prostate cancer cell, TRAMP‐C2, treated with S. frutescens methanol extract (SLE). We also observed a dose‐dependent inhibition of the Gli‐reporter activity in Shh Light II and TRAMP‐C2QGli cells treated with SLE. In addition, SLE can inhibit Gli/Hh signaling by blocking Gli1 and Ptched1 gene expression in the presence of a Gli/Hh signaling agonist (SAG). A diet supplemented with S. frutescens suppressed the formation of poorly differentiated carcinoma in prostates of TRAMP mice. Finally, we found Sutherlandioside D was the most potent compound in the crude extract that could suppress Gli‐reporter in Shh Light II cells. Together, this suggests that the S. frutescens extract may exert anti‐cancer effect by targeting Gli/Hh signaling, and Sutherlandioside D is one of the active compounds.
Atomic Observations of Microporous Materials Highly Unstable under the Electron Beam: The Cases of Ti‐Doped AlPO4‐5 and Zn–MOF‐74
Authors: Mayoral Alvaro , Sanchez‐Sanchez Manuel , Alfayate Almudena , Perez‐Pariente Joaquín , Diaz Isabel 
Published: September 2015

AbstractThis work presents the highest resolution micrographs reported so far of two beam‐sensitive microporous materials: Ti‐doped AlPO4‐5 (TAPO‐5) and the metal–organic framework Zn–MOF‐74. They were registered by means of Cs‐corrected STEM. The high‐resolution images of the TAPO‐5 along the [0 0 1] orientation allows a clear observation of the aluminophosphate‐five (AFI) type framework, and illustrates the atomic distribution of the “T” atoms of the structure. However, no definitive conclusions about Ti substitution mechanism could be afforded because of the high symmetry of the AFI framework. In the case of Zn–MOF‐74, the images were also obtained at 300 kV proving that under certain conditions of beam current this technique can provide invaluable information of an ever‐increasing variety of molecular sieves.
Regioselective C−S Bond Formation between Flavones and Arylsulfonyl Chlorides through the Use of Ammonium Iodide
Authors: Zhao Wannian , Zhou Aihua 
Published: September 2015

AbstractA novel and regioselective ammonium iodide mediated C−S bond formation protocol involving flavones and sulfonyl chlorides to generate different ArS‐substituted flavone derivatives in high yields was developed. Different from existing metal‐free C−S bond formation protocols with the use of PPh3 or I2 as the catalyst, this method provides an alternative way of constructing C−S bonds through the use of NH4I as a catalyst, which makes it highly valuable for the efficient synthesis of thioether compounds.
Bimetallic Catalysis: Asymmetric Transfer Hydrogenation of Sterically Hindered Ketones Catalyzed by Ruthenium and Potassium
Authors: Slagbrand Tove , Kivijärvi Tove , Adolfsson Hans 
Published: September 2015

AbstractAn efficient protocol for the asymmetric reduction of sterically hindered ketones under transfer‐hydrogenation conditions was developed. The corresponding chiral alcohols were obtained in good to excellent yields with enantiomeric excess values up to 99 %. The role of the cation associated with the base present in the reduction reaction was investigated. In contrast to previous studies on this catalyst system, potassium ions rather than lithium ions significantly enhanced the reaction outcome.
Highly Regioselective Isomerizing Hydroformylation of Long‐Chain Internal Olefins Catalyzed by a Rhodium Bis(Phosphite) Complex
Authors: Pandey Swechchha , Chikkali Samir H. 
Published: September 2015

AbstractThe single‐step synthesis, coordination behavior, and application of a bis(phosphite) ligand in the isomerizing hydroformylation of internal olefins was investigated. Interestingly, high‐pressure NMR spectroscopy investigations revealed unexpected inequivalency of the two phosphorus nuclei, which display bisequatorial coordination of the bis(phosphite) ligand in a trigonal bipyramidal rhodium complex. Upon employment in the isomerizing hydroformylation of the exceedingly challenging plant oil derived substrate methyl oleate, the bis(phosphite) rhodium complex revealed an unprecedented linear selectivity of 75 %.
Solvent‐Controlled C2/C5‐Regiodivergent Alkenylation of Pyrroles
Authors: Su Youla , Gao Shang , Huang Yue , Lin Aijun , Yao Hequan 
Published: September 2015

AbstractA solvent‐controlled C2/C5‐selective alkenylation of 3,4‐disubstituted pyrroles has been developed. The C3 substituent of pyrroles proved crucial to the regioselectivity. Substrates bearing directing groups at the C3 position exhibited excellent C2‐selectivities in chelation‐assisted CH activation in toluene or 1,4‐dioxane. However, a DMSO/DMF solvent system could override the chelation effect of weak directing groups, such as carboxylate and carbonyl groups, favoring instead regioselectivity towards the more electron‐rich C5 position. A series of 3‐carboxylate and 3‐carbonyl pyrroles were tested and showed moderate to good yields with good regioselectivities for both C2‐ and C5‐alkenylation process.
Dimethylzinc‐Initiated Radical Coupling of β‐Bromostyrenes with Ethers and Amines
Authors: Sølvhøj Amanda , Ahlburg Andreas , Madsen Robert 
Published: September 2015

AbstractA new coupling reaction has been developed in which β‐bromostyrenes react with ethers and tertiary amines to introduce the styryl group in the α‐position. The transformation is mediated by Me2Zn/O2 with 10 % MnCl2 and is believed to proceed by a radical addition–elimination mechanism. The ether and the amine are employed as solvent and the coupling takes place through the most stable α radical for unsymmetrical substrates. The products are obtained in moderate to good yields as the pure E isomers. The coupling can be achieved with a range of smaller cyclic and acyclic ethers/amines as well as various substituted β‐bromostyrenes.
Substrate‐Controlled Asymmetric Total Syntheses of Microcladallenes A, B, and C Based on the Proposed Structures
Authors: Sohn Te‐ik , Kim Deukjoon , Paton Robert S. 
Published: September 2015

AbstractSubstrate‐controlled asymmetric total syntheses of (+)‐microcladallenes A, B, and C have been accomplished based on the proposed structures. The syntheses of microcladallenes A and B confirmed the structures and absolute configurations of both natural products. However, the synthesis of microcladallene C, which includes seven stereogenic centers and an (R)‐bromoallene in its compact C15 framework, brought the realization that its proposed structure must be revised. The introduction of C12‐bromine into these natural products with retention of configuration relied on TiBr4‐mediated nucleophile‐assisting leaving group brominations, the stereochemical outcome of which could be attributed, at least in part, to an oxonium or halonium ion formation–fragmentation sequence through intricate neighboring group participation. In addition, the pivotal β‐oriented vicinal cis‐dichloride function in microcladallene C was elaborated through a novel tandem Cl2‐induced electrophilic cyclization/imidate chlorination process. The positive rotations of these natural products with an (R)‐bromoallene constitute exceptions to Lowe’s rule for reasons yet to be determined.
Copper‐Catalyzed Oxyboration of Unactivated Alkenes
Authors: Itoh Taisuke , Matsueda Takumi , Shimizu Yohei , Kanai Motomu 
Published: September 2015

AbstractThe first regiodivergent oxyboration of unactivated terminal alkenes is reported, using copper alkoxide as a catalyst, bis(pinacolato)diboron [(Bpin)2] as a boron source, and (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO) as an oxygen source. The reaction is compatible with various functional groups. Two regioisomers are selectively produced by selecting the appropriate ligands on copper. The products may be used as a linchpin precursor for various other functionalizations, and net processes such as carbooxygenation, aminooxygenation, and dioxygenation of alkenes can be achieved after CB bond transformations. Mechanistic studies indicate that the reaction involves the following steps: 1) Transmetalation between CuOtBu and (Bpin)2 to generate a borylcopper species; 2) regiodivergent borylcupration of alkenes; 3) oxidation of the thus‐generated CCu bond to give an alkyl radical; 4) trapping of the resulting alkyl radical by TEMPO.
ChemInform Abstract: High Pressure Phase Transitions in Scheelite Structured Fluoride: ErLiF4.
Authors: Garg Nandini , Mishra A. K. , Poswal H. K. , Tyagi A. K. , Sharma Surinder M. 
Published: September 2015

AbstractErLiF4 is prepared by solid state reaction of stoichiometric amounts of LiF and ErF3 (1.