bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication of a polymer monolithic column via redox system and its application in efficient separation of Chinese herb Rheum palmatumL.
Authors: Jiang Xiaoya , Jiao Xiaoyan , Zhang Doudou , Bai Ligai , Liu Haiyan , Yan Hongyuan 
Published: January 2017

ABSTRACTA polymer monolithic column was prepared via redox system in a stainless steel column (50 × 4.6 mm i.d.) by using 1,6‐hexanediol diacrylate as monomer and ethylene dimethacrylate as cross linking agent. Characteristics of the homemade monolithic column were investigated by scanning electron microscopy, nitrogen adsorption‐desorption and mercury intrusion porosimeter, respectively. The results showed that the resulting monolithic column occupied relative uniform porous skeleton structure. Furthermore, the monolith was tested by separating aromatic compounds in conjunction of high performance liquid chromatography with the highest column efficiency of more than 21,000 plate per meter, which was relative high for polymer‐based monolithic column with 4.6 mm i.d. At last, the monolithic column was used to simultaneously separate and quantitatively analyzes five active compounds in Chinese herb Rheum palmatum L. The validation of the method was carried out, which indicated that the accuracy represented by recovery was in the range of 98.48% to 101.57%. Limit of detection and limit of quantification for the five active compounds were less than 33.7 ng and 90.8 ng, respectively. All the results indicated that the present method was simple and efficient for quantitative analysis of the five active compounds from Chinese herb Rheum palmatum L. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44874.
Comparison of cellulose and chitin nanocrystals for reinforcing regenerated cellulose fibers
Authors: Chen Jing‐Huan , Liu Jin‐Gang , Yuan Tong‐Qi , Sun Run‐Cang 
Published: January 2017

ABSTRACTIn this study, regenerated cellulose fibers reinforced by cellulose nanocrystals (CENC) and chitin nanocrystals (CHNC) were prepared by blending the nanocrystals suspensions with the cellulose solution in NaOH/urea/water solvent at room temperature. The effect of nanocrystals' addition on the properties of spinning dopes and regenerated fibers were investigated and compared. Results showed that the obtained CENC and CHNC had different dimensions, and both of them increased the viscosity and decreased the transparency of the spinning dopes. However, the dissolution state of cellulose was not changed. CHNC had a greater influence on the properties of spinning dopes, while CENC had more obvious effect on the performance of regenerated fibers. The CENC reinforced fibers showed a higher crystallinity index as compared to the CHNC reinforced fibers. The tensile strength of the regenerated fibers was evidently improved when 3 wt % CENC or 2 wt % CHNC were added, while the elongation at break of the fibers was slightly decreased with the increase of nanocrystals content. The morphology and thermal stability of the regenerated fibers was not affected by the addition of nanocrystals. This study suggested that the dimension, group and content of nanocrystals were important factors for the reinforcement of regenerated cellulose fibers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44880.
Synthesis and photoluminescence properties of red emitting phosphor La2–xEuxLi0.5Al0.5O4 [x = 0.2–2] with K2NiF4 structure
Authors: Kasturi S. , Satish Kumar S. , Sivakumar V. 
Published: January 2017

AbstractEuropium (Eu)3+‐substituted La2Li0.5Al0.5O4 red emitting phosphors were prepared by a conventional high‐temperature solid‐state reaction method. Powder X‐ray diffraction, diffuse reflectance spectra and spectrofluorometry were used as vital characterizing tools for the phosphors. The Eu concentration dependence luminescence properties and Judd–Ofelt intensity parameters were investigated and calculated, respectively. All compositions showed an orange red emission (due to the magnetic and electric dipole transitions of the Eu3+ ion) with the appropriate Commission Internationale de l'Eclairage (CIE) colour gamut under near ultraviolet or blue ray light excitation. The calculated critical distance showed that the energy transfer occured between Eu to Eu via an exchange mechanism. The Eu1.4La0.6Li0.5Al0.5O4 composition showed the highest red emission intensity with CIE colour saturation compared with that of the commercial Eu‐activated yttrium oxysulfide red phosphor.
Streptomyces venezuelae TX‐TL – a next generation cell‐free synthetic biology tool
Authors: Moore Simon J. , Lai Hung‐En , Needham Hannah , Polizzi Karen M. , Freemont Paul S. 
Published: January 2017

AbstractStreptomyces venezuelae is a promising chassis in synthetic biology for fine chemical and secondary metabolite pathway engineering. The potential of S. venezuelae could be further realized by expanding its capability with the introduction of its own in vitro transcription‐translation (TX‐TL) system. TX‐TL is a fast and expanding technology for bottom‐up design of complex gene expression tools, biosensors and protein manufacturing. Herein, we introduce a S. venezuelae TX‐TL platform by reporting a streamlined protocol for cell‐extract preparation, demonstrating high‐yield synthesis of a codon‐optimized sfGFP reporter and the prototyping of a synthetic tetracycline‐inducible promoter in S. venezuelae TX‐TL based on the tetO‐TetR repressor system. The aim of this system is to provide a host for the homologous production of exotic enzymes from Actinobacteria secondary metabolism in vitro. As an example, the authors demonstrate the soluble synthesis of a selection of enzymes (12–70 kDa) from the Streptomyces rimosus oxytetracycline pathway.
Optimized Reaction Conditions Enable the Hydration of Non‐natural Substrates by the Oleate Hydratase from Elizabethkingia meningoseptica
Authors: Demming Rebecca M. , Otte Konrad B. , Nestl Bettina M. , Hauer Bernhard 
Published: January 2017

AbstractThe oleate hydratase from Elizabethkingia meningoseptica (Em‐OAH) catalyzes the hydration of oleic acid (C18) to (R)‐10‐hydroxystearic acid. In previous work, low activity of Em‐OAH towards chemically synthesized (Z)‐undec‐9‐enoic acid (C11) was observed. Product formation in the hydration of the truncated C11 substrate was improved by optimizing the reaction conditions by applying statistical experiment design. Optimized reaction conditions resulted in a 2.8‐fold increase in product formation in just one quarter of the time (64 % conversion in 28 h). The applicability has been assessed in the upscaling of the conversion of (Z)‐undec‐9‐enoic acid to (S)‐10‐hydroxyundecanoic acid (132 mg product, >95 % purity). Reaction conditions developed for the hydration of C11 facilitated the first hydration of non‐natural alkenes. By using a fatty acid dummy substrate, 1‐decene was successfully hydrated to (S)‐2‐decanol with excellent stereoselectivity and 50 % conversion after four days of incubation.
Probing Excimers of Pt(II) Compounds with Phenyl‐1,2,3‐Triazolyl and Pyridyl‐1,2,4‐Triazolyl Chelate Ligands by Means of Electrochemiluminescence
Authors: Xiang Guiming , Wang Xiang , Li Michelle S. M. , Lac Kevin , Wang Suning , Ding Zhifeng 
Published: January 2017

AbstractPt(II) complexes are well known for their excellent phosphorescence properties. Here, we report the results of an electrochemical and electrochemiluminescence (or electrogenerated chemiluminescence, ECL) study of two Pt complexes with phenyl‐1,2,3‐triazolyl and pyridyl‐1,2,4‐triazolyl chelate ligands to explore their effectiveness as ECL luminophores. The two Pt complexes with the two substituents CF3 and t‐Bu on the pyridyl‐1,2,4‐triazolyl ligand (Pt1 and Pt2) were purposely chosen to see the structure and ECL correlations. It was discovered that excimers, the excited states of analyte dimers, contributed mainly to the ECL production. These two complexes exhibited weak ECL efficiencies following the annihilation mechanism. However, ECL was enhanced with co‐reactants such as tri‐n‐propylamine for Pt1 and ammonium persulfate for Pt2. Spooling ECL spectroscopy was utilized to gain analytical insight into light emission mechanisms. It is shown that excimers were probed easily by means of ECL.
Equiatomic AEAuX (AE=Ca−Ba, X=Al−In) Intermetallics: A Systematic Study of their Electronic Structure and Spectroscopic Properties
Authors: Benndorf Christopher , Stegemann Frank , Seidel Stefan , Schubert Lea , Bartsch Manfred , Zacharias Helmut , Mausolf Bernhard , Haarmann Frank , Eckert Hellmut , Pöttgen Rainer , Janka Oliver 
Published: January 2017

AbstractThe three intermetallic compounds SrAuGa, BaAuAl and BaAuGa were synthesised from the elements in niobium ampoules. The Sr compound crystallises in the orthorhombic KHg2‐type structure (Imma, a=465.6(1), b=771.8(2), c=792.6(2) pm, wR2=0.0740, 324 F2 values, 13 variables), whereas the Ba compounds were both found to crystallise in the cubic non‐centrosymmetric LaIrSi‐type structure (P213, BaAuAl: a=696.5(1) pm; wR2=0.0427, 446 F2 values, 12 variables; BaAuGa: a=693.49(4) pm, wR2=0.0717, 447 F2 values, 12 variables). The samples were investigated by powder X‐ray diffraction and their structures refined on the basis of single‐crystal X‐ray diffraction data. The title compounds, along with references from the literature (CaAuAl, CaAuGa, CaAuIn, and SrAuIn), were characterised further by susceptibility measurements and 27Al and 71Ga solid‐state NMR spectroscopy. Theoretical calculations of the density of states (DOS) and the NMR parameters were used for the interpretation of the spectroscopic data. The electron transfer from the alkaline‐earth metals and the group 13 elements onto the gold atoms was investigated through X‐ray photoelectron spectroscopy (XPS), classifying these intermetallics as aurides.
Ligand versus Complex: C−F and C−H Bond Activation of Polyfluoroaromatics at a Cyclic (Alkyl)(Amino)Carbene
Authors: Paul Ursula S. D. , Radius Udo 
Published: January 2017

AbstractC−F and C−H bond activation reactions of polyfluoroaromatics at the cyclic (alkyl)(amino)carbene (cAAC) cAACmethyl (1) are reported. Studies on the C−F bond activation using the cAAC‐stabilized nickel(0) complex [Ni(cAACmethyl)2] (2) have shown that 2 does not react with fluorinated arenes. However, these investigations led to the observation of C−F bond cleavage of perfluorinated arenes by the carbene ligand cAACmethyl (1) itself. The reaction of 1 with C6F6, C6F5−C6F5, C6F5−CF3, and C5F5N afforded the insertion products of cAAC into one of the C−F bonds of the substrate, that is, the C−F bond activation products (cAACmethyl)F(Arf) (Arf=C6F5 4 a, C6F4−C6F5 4 b, C6F4−CF3 4 c, C5F4N 4 d). These products decompose readily upon heating to 80 °C within a few hours in solution with formation of ionic iminium salts [(cAACmethyl)(Arf)][X] 6 a–d or neutral alkenyl perfluoroaryl imine compounds 7 a–d. The compounds (cAACmethyl)F(Arf) 4 a–d readily transfer fluoride, which has been exemplified by the fluoride transfer of all compounds using BF3 etherate as fluoride acceptor. Fluoride transfer has also been achieved starting from (cAACmethyl)F(C6F4‐CF3) (4 c) or (cAACmethyl)F(C5F4N) (4 d) to other selected substrates such as trimethylchlorosilane, benzoyl chloride and tosyl chloride. Instead of C−F bond activation, insertion of the cAAC into the C−H bond was observed if 1 was treated with the partially fluorinated arenes C6F5H, 1,2,4,5‐C6F4H2, 1,3,5‐C6F3H3, and 1,3‐C6F2H4. The compounds (cAACmethyl)H(Arf) (Arf=C6F5 12 e, 2,3,5,6‐C6F4H 12 f, 2,4,6‐C6F3H2 12 g and 2,6‐C6F2H3 12 h) have been isolated in good yields and have been characterized including X‐ray analysis. Fluorobenzene C6FH5 (pKa ≈37), the least C−H acidic fluoroarene used in this study, does not react. In order to investigate the scope and limitations of this type of cAAC C−H bond activation reaction, cAACmethyl (1) was treated with several other reagents of different C−H acidity such as imidazolium salts, imidazoles, esters, and trimethylphosphine. These investigations led to the isolation and characterization of the compounds [(cAACmethyl)H(R2ImMe2)]X (13 a,b), (cAACmethyl)H(ImR2) (14 a–c), (cAACmethyl)H(CH(COOCH3)2) (15 b) and (cAACmethyl)H(CH2‐PMe2) (16). Deprotonation of [(cAACmethyl)H(Me2ImMe2)][BF4] (13 a) at the cAAC carbon atom using KHMDS as a base led to isolation and structural characterization of the cAACmethyl‐NHC heterodimer (17).
Personalized, assessment‐based, and tiered medical education curriculum integrating treatment guidelines for atrial fibrillation
Authors: Lee Brian C. , Ruiz‐Cordell Karyn D. , Haimowitz Steven M. , Williams Cara , Stambler Bruce S. , Mandarakas Anthia 
Published: January 2017

BackgroundThis continuing medical education (CME) curriculum utilizes the Learner Assessment Platform (LAP), providing learners with personalized educational pathways related to atrial fibrillation treatment.HypothesisThere are improvements in knowledge among physician learners after CME, especially among LAP learners.MethodsIn this LAP‐based curriculum, an evaluation of learner deficits on designated learning objectives was conducted in tier 1 and used to direct learners to individualized tier 2 activities. Performance was assessed across learner tracks from baseline to learners’ final intervention. Retention data were measured by the postcurriculum assessment, completed 8 weeks after the learners last intervention. Additionally, each activity included a unique matched set of pretest and post‐test questions assessing the 4 learner domains: knowledge, competence, confidence, and practice patterns.ResultsSignificant learner improvement was measured across the curriculum over all 4 learner‐domains: 48% (P < 0.0005), 78% (P < 0.0005), 21% (P < 0.0005), and 20% (P < 0.0005) improvements for knowledge, competence, confidence, and practice, respectively. Significant gains in participant performance scores (28% increase, P < 0.0005) by the final activity was observed. Learners who participated in the LAP (N = 989) demonstrated greater improvement in performance from baseline compared to non‐LAP learners (41% increase for LAP vs 23% and 26% increase for non‐LAP learners who completed 1 (N = 1899) or ≥2 (N = 533) activities, respectively, P = 0.003).ConclusionsThe participant population (N = 3421) achieved statistically significant improvement across the curriculum, with LAP learners showing greater performance gains compared to non‐LAP learners. These findings support the value of the LAP methodology in providing a cumulative and individualized CME experience.
How Selective are Hsp90 Inhibitors for Cancer Cells over Normal Cells?
Authors: Wang Yao , Koay Yen Chin , McAlpine Shelli R. 
Published: January 2017

AbstractSelectively inhibiting target proteins in cancer cells over normal cells is one of the most critical features of a successful protein inhibitor for clinical applications. By evaluating and comparing the impact of a clinical N‐terminal heat shock protein 90 (Hsp90) inhibitor, AUY922 (luminespib), on Hsp90 inhibition‐associated cellular events in cancer cells versus normal cells, we found that it produces similar phenotype characteristics in both cell types, indicating that AUY922 is not selective for targeting Hsp90 in tumor cells. By comparison, the C‐terminal Hsp90 modulator SM258 suppresses cell proliferation, triggers apoptosis, regulates the expression of Hsp90‐associated heat shock proteins, and enhances the degradation of Hsp90′s client proteins preferentially in cancer cells over normal cells. Our findings support a new paradigm that AUY922 is not tumor selective, whereas SM258 is more selective and likely acts through an Hsp90‐dependent mechanism.
Lignin Depolymerisation and Lignocellulose Fractionation by Solvated Electrons in Liquid Ammonia
Authors: Prinsen Pepijn , Narani Anand , Rothenberg Gadi 
Published: January 2017

AbstractWe explored the depolymerisation of several lignins in liquid ammonia at relatively high temperatures and pressures (120 °C and 88 bar). Five different lignins were tested: Indulin AT kraft, Protobind 1000 soda, wheat straw organosolv, poplar organosolv and elephant grass‐milled wood lignin (EG MWL). In pure liquid ammonia, all lignins underwent slow incorporation of nitrogen into their structure, resulting in higher molecular weight and polydispersity index. Subsequently, we show a reductive depolymerisation by solvated electrons at room temperature by adding sodium metal to the liquid ammonia without any external hydrogen donor. The netto yields of bio‐oil are low for technical lignins (10–23 %), but with higher yields of alkylphenols. In the case of native EG MWL, netto yields of 40 % bio‐oil were achieved. Finally, when the room temperature method was applied to poplar wood fibre, we observe improved delignification upon the addition of sodium compared to poplar wood fractionation in pure liquid ammonia.
Chronic social instability in adult female rats alters social behavior, maternal aggression and offspring development
Authors: Pittet Florent , Babb Jessica A. , Carini Lindsay , Nephew Benjamin C. 
Published: January 2017

AbstractWe investigated the consequences of chronic social instability (CSI) during adulthood on social and maternal behavior in females and social behavior of their offspring in a rat model. CSI consisted of changing the social partners of adult females every 2–3 days for 28 days, 2 weeks prior to mating. Females exposed to CSI behaved less aggressively and more pro‐socially towards unfamiliar female intruders. Maternal care was not affected by CSI in a standard testing environment, but maternal behavior of CSI females was less disrupted by a male intruder. CSI females were quicker to attack prey and did not differ from control females in their saccharin consumption indicating, respectively, no stress‐induced sensory‐motor or reward system impairments. Offspring of CSI females exhibited slower growth and expressed more anxiety in social encounters. This study demonstrates continued adult vulnerability to social challenges with an impact specific to social situations for mothers and offspring.
Invasive rodents have multiple indirect effects on seabird island invertebrate food web structure
Authors: Thoresen Joshua J. , Towns David , Leuzinger Sebastian , Durrett Mel , Mulder Christa P. H. , Wardle David A. 
Published: January 2017

AbstractBurrowing seabirds that nest on islands transfer nutrients from the sea, disturb the soil through burrowing, damage tree foliage when landing, and thereby modify the surface litter. However, seabirds are in decline worldwide, as are their community‐ and ecosystem‐level impacts, primarily due to invasive predatory mammals. The direct and indirect effects of seabird decline on communities and ecosystems are inherently complex. Here we employed network analysis, as a means of simplifying ecological complexity, to better understand the effects seabird loss may have on island invertebrate communities. Using data on leaf litter communities, we constructed invertebrate food webs for each of 18 offshore oceanic islands in northeastern New Zealand, nine of which have high seabird densities and nine of were invaded by rats. Ten network topological metrics (including entropy, generality, and vulnerability) were compared between rat‐invaded and uninvaded (seabird‐dominant) islands. We found that, on rat‐invaded islands, the invertebrate food webs were smaller and less complex than on their seabird‐dominated counterparts, which may be due to the suppression of seabird‐derived nutrients and consequent effects on trophic cascades. This decreased complexity of food webs due to the presence of rats is indicative of lower ecosystem resistance via lower trophic redundancy. Our results show that rat effects on island ecosystems are manifested throughout entire food webs, and demonstrate how network analysis may be useful to assess ecosystem recovery status as these invaded islands are restored.
A Novel Superoxide Anion Biosensor for Monitoring Reactive Species of Oxygen Released by Cancer Cells
Authors: Crulhas Bruno P. , Recco Lucas C. , Delella Flávia K. , Pedrosa Valber A. 
Published: January 2017

AbstractIn this study, novel sensitive and selective hydrogel microstructures to detect superoxide anions released by cancer cells, based on electrochemical biosensors, are proposed. Ferrocene was coupled with superoxide dismutase within a poly(ethylene glycol) diacrylate hydrogel matrix. The pre‐polymer solution was patterned by photolithography in gold microelectrodes fabricated on top of glass slides. The biosensor was characterized by electrochemical impedance spectroscopy and cyclic voltammetry, and was able to detect superoxide anions in a wide linear range from 5 to 100 μM, with a low detection limit of 0.001 μM and sensitivity of 14.1 nA μM/mm2. Moreover, the biosensor was able to directly detect reactive oxygen species released from prostate cells. Furthermore, the reproducibility, stability and selectivity of the biosensor achieved better results when compared with the previous report, so this methodology can be used in physiological and pathological detection of reactive oxygen species, providing a powerful platform for clinical diagnostics in the future.
Linking the Regulatory and Reimbursement Processes for Medical Devices: The Need for Integrated Assessments
Authors: Ciani Oriana , Wilcher Britni , van Giessen Anoukh , Taylor Rod S. 
Published: January 2017

AbstractMuch criticism has been directed at the licencing requirements for medical devices (MDs) as they often result in a lack of robust evidence to inform health technology assessment (HTA) decisions. To better understand the current international decisional framework on MD technologies, we undertook three linked research studies: a review of the device regulatory procedures, a survey of current HTA practices and an empirical comparison of HTA reports of drugs versus MDs. Our review confirms that current device regulatory processes across the globe are substantially less stringent than drugs. As a result, international HTA agencies report that they face a number of challenges when assessing MDs, including reliance on suboptimal data to make clinical and cost‐effectiveness decisions. Whilst many HTA agencies have adapted their processes and procedures to handle MD technology submissions, in our comparison of HTA reports we found little evidence of the application of methodologies that take account of device‐specific issues, such as incremental development. Overall, our research reinforces the need for better linkage between licencing and HTA and the development and application of innovative HTA methodologies with the objective of securing faster patient access for those technologies that can be shown to represent good value for money. © 2017 The Authors.Health EconomicsPublished by John Wiley & Sons, Ltd.