bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Even‐Handed Approach: Strategies for the Deployment of Racemic Chiral Catalysts
Authors: Evans Louise A. , Hodnett Neil S. , Lloyd‐Jones Guy C. 
Published: January 2012

AbstractAsymmetric catalysis is predominantly associated with the use of enantiomerically pure chiral ligands and catalysts. Although racemic chiral catalysts have been employed quite extensively in polymerization, their utility in mainstream organic synthesis and catalyst development has arguably been rather overlooked. This Minireview collates various themes for the strategic application of racemic ligands and catalysts, ranging from the estimation of selectivity and determination of enantiomeric excess, through to control of regio‐ and stereochemical outcomes, and mechanistic studies. What emerges is a clear picture that, in isolation or in concert with enantiopure catalysts, the “even‐handed” approach has much to offer.
Preparation of sulfonated poly(ethylene terephthalate) submicron fibrous membranes for removal of basic dyes
Authors: Chegoonian P. , Feiz M. , Ravandi S. A. Hosseini , Mallakpour S. 
Published: January 2012

AbstractIn this investigation, a nanofibrous sulfonated poly(ethylene terephthalate) (SPET) membrane was prepared by electrospinning of the SPET solution in trifluoroaceticacid (TFA)/dichloromethane (DCM) mixture. The produced nanofibers had diameter ranging from 300 nm to 1 μm. The performance of this membrane's separation process was evaluated under different operating conditions. The influence of the electrospinning and filtration process parameters, such as concentration, applied voltage, deposition time, operating pressure, and filtration time on rejection of C.I. Basic Blue 3 were studied. The dead‐end recirculation ultrafiltration set‐up was employed. Under optimum conditions (concentration of 20% (w/v) of SPET, applied voltage of 20 kV and deposition time of 3 h) the removal of the aforementioned dye was 98%. Operating pressure has posed a significant influence on the membrane's separation performance, whereas the operating time had some effect on the separation performance. Two equilibrium adsorption isotherms: Langmuir and Freundlich were fitted to the dyes' equilibrium sorption data on SPET membrane at different feed concentrations. The Freundlich isotherm was found to well represent the measured adsorption data based on the higher coefficient of determination (r2). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
River dolphin distribution in regulated river systems: implications for dry‐season flow regimes in the Gangetic basin
Authors: Choudhary Sunil , Dey Sushant , Dey Subhashish , Sagar Viveksheel , Nair Tarun , Kelkar Nachiket 
Published: January 2012

ABSTRACT

River flow regulation and fragmentation is a global threat to freshwater biodiversity, ecosystem processes, and associated human activities. Large dams in the Ganges river basin of the Indian subcontinent have severely altered natural flow regimes, particularly in the low‐flow dry season. Altered flows could have negative impacts on endangered species such as the Ganges river dolphin Platanista gangetica.
Habitat use by river dolphins was investigated in relation to river channel depth and morphology, over 332 km of the flow‐regulated Gandak River in India. Dolphin distribution patterns were compared across multiple spatial scales in the Gandak, Kosi, Chambal, Sone Rivers and the upper and lower sections of the Ganges main stem.
Dolphin presence was recorded in 40% of segments in the Gandak river, with a best count of 257 (range 250–267) and average individual encounter rates at 0.75 dolphins km‐1 (SD 0.89). Bayesian zero-inflated spatial models showed that river dolphin abundance was positively influenced by river depth, presence of meanders and corresponded closely with gillnet fishing. Minimum mid‐channel depth requirements were estimated at 5.2 m for dolphin adults and between 2.2 and 2.4 m for mother–calf pairs.
Adult dolphins showed highly similar habitat preferences across regulated or unregulated rivers, for depths >5 m, and meandering channels. Dry‐season habitat availability was reduced as the degree of flow regulation increased across rivers, mainly owing to loss of lateral and longitudinal channel connectivity.
Overall encounter rates were reduced from >3 km‐1 in less regulated stretches, to <0.3 km‐1 in regulated rivers. Clustering of dolphins in deep pools increased along the gradient of river flow reduction, with dolphins almost absent from intervening segments because of low flow rates. These results indicate the importance of maintaining adequate dry‐season flows to ensure river habitat availability and connectivity for dolphins. Copyright © 2012 John Wiley & Sons, Ltd.
A breath of fresh air: avoiding anoxia and mortality of freshwater turtles in fyke nets by the use of floats
Authors: Larocque Sarah M. , Cooke Steven J. , Blouin‐Demers Gabriel 
Published: January 2012

ABSTRACT

Freshwater turtles are susceptible to drowning in commercial fishing nets and this is a major conservation concern. Methods to mitigate turtle bycatch mortality typically involve reducing the capture of bycatch using gear modifications. Another method to reduce mortality is to keep bycatch alive following capture.
Using physiological measures of anoxia, this study determined whether providing air spaces using floats within fyke nets could prevent turtles from drowning. In a controlled setting, blood lactate and pH of painted turtles (Chrysemys picta) experimentally introduced into submerged nets, nets with floats, and nets that breached the surface were compared. While emulating commercial fishing practices – where turtles and fish voluntarily entered nets – catch rates and compositions as well as blood lactate in turtles captured were compared in submerged nets with and without floats.
Painted turtles in submerged nets exhibited elevated blood lactate and pronounced acidosis compared with turtles from nets with floats and surfaced nets.
Catch rates and compositions from emulated fishing were statistically similar in nets with and without floats; however, total fish catches were roughly one‐third less in nets with floats. The same pattern of physiological disturbance was observed with turtles captured in submerged nets with and without floats as in the controlled experiment.
Overall, blood physiology indicated that anoxia occurred in turtles in submerged nets while nets with floats reduced physiological disturbance. However, variation in blood lactate levels when fishing fyke nets with floats suggests that turtles were experiencing slight anoxia and so the size of air spaces may be important in allowing access to air. Creating air spaces in fyke nets using floats is a simple and cost‐effective method to avoid the drowning of turtles.Copyright © 2012 John Wiley & Sons, Ltd.
The absorption and emission spectrum of the magnetic Herbig Ae star HD 190073
Authors: Cowley C.R. , Hubrig S. 
Published: January 2012

AbstractWe determine abundances from the absorption spectrum of the magnetic Herbig Ae star HD 190073 (V1295 Aql). The observations are primarily from HARPS spectra obtained at a single epoch. We accept arguments that the presence of numerous emission lines does not vitiate a classical abundance analysis, though it likely reduces the achievable accuracy. Most abundances are closely solar, but several elements show departures of a factor of two to three, as an earlier study has also shown. We present quantitative measurements of more than 60 emission lines, peak intensities, equivalent widths, and FWHM's. The latter range from over 200 km s–1(Hα, He D3) down to 10–20 km s–1(forbidden lines). Metallic emission lines have intermediate widths. We eschew modeling, and content ourselves with a presentation of the observations a successful model must explain. Low‐excitation features such as the Na I D‐lines and [O I] appear with He I D3, suggesting proximate regions with widely differing Te and Ne as found in the solar chromosphere. The [O I] and [Ca II] lines show sharp, violet‐shifted features. Additionally, [Fe II] lines appear tobe weakly present in emission (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A magnetic cycle of τ Bootis? The coronal and chromospheric view
Authors: Poppenhaeger K. , Günther H.M. , Schmitt J.H.M.M. 
Published: January 2012

Abstractτ Bootis is a late F‐type main sequence star orbited by a Hot Jupiter. During the last years spectropolarimetric observations led to the hypothesis that this star may host a global magnetic field that switches its polarity once per year, indicating a very short activity cycle of only one year duration. In our ongoing observational campaign, we have collected several X‐ray observations with XMM‐Newton and optical spectra with TRES/FLWO in Arizona to characterize τ Boo's corona and chromosphere over the course of the supposed one‐year cycle. Contrary to the spectropolarimetric reconstructions, our observations do not show indications for a short activity cycle (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling spatio‐temporal nonlocality in mean‐field dynamos
Authors: Rheinhardt M. , Brandenburg A. 
Published: January 2012

AbstractWhen scale separation in space or time is poor, the mean‐field α effect and turbulent diffusivity have to be replaced by integral kernels by which the dependence of the mean electromotive force on the mean magnetic field becomes nonlocal. Earlier work in computing these kernels using the test‐field method is now generalized to the case in which both spatial and temporal scale separations are poor. The approximate form of the kernel for isotropic stationary turbulence is such that it can be treated in a straightforward manner by solving a partial differential equation for the mean electromotive force. The resulting mean‐field equations are solved for oscillatory α –shear dynamos as well as α2 dynamos with α linearly depending on position, which makes this dynamo oscillatory, too. In both cases, the critical values of the dynamo number is lowered due to spatio‐temporal nonlocality.When scale separation in space or time is poor, the mean‐field α effect and turbulent diffusivity have to be replaced by integral kernels by which the dependence of the mean electromotive force on the mean magnetic field becomes nonlocal. Earlier work in computing these kernels using the test‐field method is now generalized to the case in which both spatial and temporal scale separations are poor. The approximate form of the kernel for isotropic stationary turbulence is such that it can be treated in a straightforward manner by solving a partial differential equation for the mean electromotive force. The resulting mean‐field equations are solved for oscillatory α –shear dynamos as well as α2 dynamos
Measurement of quetiapine and four quetiapine metabolites in human plasma by LC‐MS/MS
Authors: Fisher Danielle S. , Handley Simon A. , Taylor David , Flanagan Robert J. 
Published: January 2012

ABSTRACTThere is interest in monitoring plasma concentrations of N‐desalkylquetiapine in relation to antidepressant effect. A simple LC‐MS/MS method for quetiapine and four metabolites in human plasma (50 μL) has been developed to measure concentrations of these compounds attained during therapy. Analytes and internal standard (quetiapine‐d8) were extracted into butyl acetate–butanol (10:1, v/v) and a portion of the extract analysed by LC‐MS/MS (100 × 2.1 mm i.d. Waters Spherisorb S5SCX; eluent: 50 mmol/L methanolic ammonium acetate, pH* 6.0; flow‐rate 0.5 mL/min; positive ion APCI‐SRM, two transitions per analyte). Assay calibration (human plasma calibrators) was linear across the ranges studied (quetiapine and N‐desalkylquetiapine 5–800, quetiapine sulfoxide 100–15,000, others 2–100 µg/L). Assay validation was as per FDA guidelines. Quetiapine sulfone was found to be unstable and to degrade to quetiapine sulfoxide. In 47 plasma samples from patients prescribed quetiapine (prescribed dose 200–950 mg/day), the (median, range) concentrations found (µg/L) were: quetiapine 83 (7–748), N‐desalkylquetiapine, 127 (7–329), O‐desalkylquetiapine 12 (2–37), 7‐hydroxyquetiapine 3 (<1–48), and quetiapine sulfoxide 3,379 (343–21,704). The analyte concentrations found were comparable to those reported by others except that the concentrations of the sulfoxide were markedly higher. The reason for this discrepancy in unclear. Copyright © 2012 John Wiley & Sons, Ltd.
Applications of Shannon's Entropy Theory to Naphtha Pyrolysis Simulation
Authors: Zhang L. , Chen B. 
Published: January 2012

AbstractShannon's theory is applied for the first time to the simulation of naphtha pyrolysis for estimating selective coefficients of the primary reaction and predicting the feedstock component content. Compared with other methods, this approach can be extrapolated and provides more accurate results. Furthermore, it requires much less experimental data. Not only can exact constraints be used but also uncertainties can be specified by the user, resulting in a highly flexible model. The results demonstrate the effectiveness of Shannon's maximum entropy theory in obtaining the missing information for models of the naphtha pyrolysis process.
Relevance of Photocatalysis prior to Biological Treatment of Organic Pollutants – Selection Criteria
Authors: Fourcade F. , Yahiat S. , Elandaloussi K. , Brosillon S. , Amrane A. 
Published: January 2012

AbstractThe relevance of a photocatalytic pretreatment prior to a biological process for removal of organic pollutants was examined. Owing to the significant residual amount and toxicity, amitrole was not relevant. High mineralization allowed to remove bisphenol A and 2,4‐dichlorophenoxyacetic acid. Isoproturon and diuron cannot be considered due to the slight evolution of chemical oxygen demand/total organic carbon (COD/TOC) and average oxidation state during irradiation. After photocatalysis, the ratio of biological oxygen demand (BOD5)/COD remained below the biodegradability limit (0.4) for the rest of the molecules. A favorable COD/TOC trend (decrease during irradiation) was recorded for dimethoate and antibiotics. However, dimethoate and sulfamethoxazole seemed not pertinent due to the long time span for their removal. Since a decrease of toxicity was only recorded for tylosine, it can be selected for subsequent tests.
Nuclear features in endometrial cytology: Comparison of endometrial glandular and stromal breakdown and endometrioid adenocarcinoma grade 1
Authors: Norimatsu Yoshiaki , Shigematsu Yumie , Sakamoto Shingo , Ohsaki Hiroyuki , Yanoh Kenji , Kawanishi Namiki , Kobayashi Tadao K. 
Published: January 2012

AbstractThis study was to clarify the nuclear features of “condensed clusters of stromal cells (EGBD‐stromal cells)” and “metaplastic clumps with irregular protrusions (EGBD‐metaplastic cells)” which may be recognized in endometrial glandular and stromal breakdown (EGBD) cases in liquid‐based cytologic (LBC) preparations of endometrial brushings. The material consists of cytologic smears of 20 cases of proliferative endometrium (PE), 20 cases of EGBD, and 20 cases of endometrioid adenocarcinoma grade 1 (G1) for which histopathological diagnosis was obtained by endometrial curettage. Nuclear findings were examined in PE cells, EGBD‐stromal cells, EGBD‐metaplastic cells, and G1 cells, respectively.It was examined about the following items: (1) Nuclear shape; (2) A long/minor axis ratio in cell nuclei; (3) An area of cell nuclei; (4) Overlapping nuclei; (5) The distribution pattern of nuclei within cell clusters.The following observations were made: (1) In PE cells, round‐oval nuclei appeared to predominate, overlapping nuclei were not observed, and a slightly abnormal distribution pattern of nuclei was recorded; (2) In EGBD‐stromal cells, reniform nuclei were characteristically observed, nuclei had small size and a generally elongated appearance, overlapping nuclei were recognized, and a remarkable abnormal distribution pattern of nuclei was found; (3) In EGBD‐metaplastic cells, spindle nuclei were a characteristic feature, nuclei were larger in size and had a bipolar appearance, overlapping nuclei with moderately abnormal distribution pattern of nuclei were identified; (4) In G1 cells round‐oval nuclei predominated, overlapping nuclei with moderately abnormal distribution pattern of nuclei were found.The study demonstrates that the analysis of selected nuclear findings appears to be very useful in the cytopathological assessment of endometrial lesions in LBC samples, especially for the discrimination of EGBD and G1. Diagn. Cytopathol. 2012. © 2012 Wiley Periodicals, Inc.
A case of blastic plasmacytoid dendritic cell neoplasm: Cytomorphological findings of the touch imprint specimen of lymph node
Authors: Nakatsuka Shin‐ichi , Nagano Teruaki , Kimura Hayato , Nagatomo Tadasuke , Urase Yuriko , Hashimoto Koji 
Published: January 2012

AbstractThe patient is a 75‐year‐old man with axillary lymphadenopathy presenting an indurated papule on his buttock. Touch imprint cytology of the biopsied axillary lymph node revealed the monotonous appearance of medium‐sized tumor cells. The nuclei had a slightly irregular contour, finely dispersed chromatin, and a conspicuous nucleolus. Some tumor cells had intracytoplasmic microvacuoles. Immunohistochemistry of the imprint specimens showed that the tumor cells were positive for CD56 and CD123. Histological diagnosis of the lesion was blastic plasmacytoid dendritic cell neoplasm (BPDCN). Epstein‐Barr virus‐encoded RNAs were not detected in the tumor cells. Neither immunoglobulin heavy chain genes nor T‐ cell receptor genes was clonally rearranged. BPDCN should be strongly considered during the differential diagnosis of CD56‐positive neoplasms of the skin. We demonstrated a possible contribution of the cytomorphological and immunohistochemical findings of the touch imprint specimens to the diagnosis of BPDCN. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc.
Intrapancreatic accessory spleen: A case report and review of literature
Authors: Rodriguez Erika , Netto George , Li Qing Kay 
Published: January 2012

AbstractIntrapancreatic accessory spleen is not an uncommon entity and usually located in the tail of the pancreas. Most of them are asymptomatic and incidental findings on radiologic study or at autopsy. On imaging study, it appears to be a well‐defined, solitary, and hypervascular lesion; therefore, it may be confused with pancreatic neoplasms, such as neuroendocrine neoplasm, well‐differentiated adenocarcinoma, solid pseudopapillary tumor, or metastatic tumor to the pancreas. As such, the diagnostic fine‐needle aspiration biopsy of the lesion may be performed. Several case reports describing cytological features of the lesion have been published in recent years. Among them, the most commonly identified cytological findings are sheets of a heterogeneous population of lymphocytes and prominent traversing blood vessels. Herein, we report an unusual EUS‐FNA case of intrapancreatic accessory spleen. In addition to above previously well‐described cytological features, our case revealed many cells with fine granular chromatin and areas with pseudo rosette‐like architecture, mimicking and engendering the differential diagnosis of pancreatic neuroendocrine tumors. Although cytological findings of our case are rare, they may extend our current knowledge and provide additional differential diagnostic information for this entity. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc.
Ca2NiSn2 – A Polymorphic Intermetallic Phase: Atomic and Electronic Structure as well as a Topological Description of the Phase Transition by a Sigmatropic‐Type Rearrangement of Ni and Sn Atoms
Authors: Siggelkow Lisa , Hlukhyy Viktor , Fässler Thomas F. 
Published: January 2012

AbstractThe synthesis and structural characterization of two polymorphic modifications of the intermetallic compound Ca2NiSn2 are described. The monoclinic modification mC‐Ca2NiSn2 is obtained by arc melting and rapid cooling and forms two‐dimensional Ni–Sn slabs that contain four‐ and six‐membered rings. These nets are interconnected by Sn2 dumbbells and thus 12‐membered rings form between the slabs. The cavities of the resulting three‐dimensional network are filled with Ca atoms. At annealing temperatures between 800 and 870 °C, an orthorhombic modification oP‐Ca2NiSn2 forms. The two‐dimensional Ni–Sn substructure contains Ni–Sn nets of four‐ and six‐membered rings. Sn2 dumbbells coordinate to these nets end‐on to form additional five‐membered Ni–Sn rings. The resulting slabs are separated by Ca atoms. Temperature‐dependent synthesis and differential thermal analysis experiments indicate that the monoclinic modification mC‐Ca2NiSn2 is a metastable modification. Two approaches to the topological description of the phase transition are presented: 1) a conversion by a simple shift of ribbons of atomic layers and 2) a least‐motion process describing the topology of the phase transformation by an electrocyclic mechanism through Ni–Sn bond scission and formation analogous to sigmatropic shifts known for organic molecules. The electronic structures and chemical bonding are discussed in terms of DFT calculations, including density of states, band structures and a topological analysis of the electron localization function, which revealed covalent Sn2–Sn2 bonds with partial π bonding of the Sn2 dumbbells in mC‐Ca2NiSn2 and a short Sn2–Sn3 contact with dominant lone‐pair character at the terminal Sn2 atom in oP‐Ca2NiSn2.
Synthesis and Evaluation of Lipophilic BTBP Ligands for An/Ln Separation in Nuclear Waste Treatment: The Effect of Alkyl Substitution on Extraction Properties and Implications for Ligand Design
Authors: Lewis Frank W. , Harwood Laurence M. , Hudson Michael J. , Distler Petr , John Jan , Stamberg Karel , Núñez Ana , Galán Hitos , Espartero Amparo G. 
Published: January 2012

AbstractFour new 6,6′‐bis(1,2,4‐triazin‐3‐yl)‐2,2′‐bipyridine (BTBP) ligands, which contain either additional alkyl groups on the pyridine rings or seven‐membered aliphatic rings attached to the triazine rings, have been synthesized, and the effects of the additional alkyl substitution in the 4‐ and 4′‐positions of the pyridine rings on their extraction properties with LnIII and AnIII cations in simulated nuclear waste solutions have been studied. The speciation of ligand 13 with some trivalent lanthanide nitrates was elucidated by 1H NMR spectroscopic titrations and ESI‐MS. Although 13 formed both 1:1 and 1:2 complexes with LaIII and YIII, only 1:2 complexes were observed with EuIII and CeIII. Quite unexpectedly, both alkyl‐substituted ligands 12 and 13 showed lower solubilities in certain diluents than the unsubstituted ligand CyMe4‐BTBP. Compared to CyMe4‐BTBP, alkyl‐substitution was found to decrease the rates of metal‐ion extraction of the ligands in both 1‐octanol and cyclohexanone. A highly efficient (DAm > 10) and selective (SFAm/Eu > 90) extraction was observed for 12 and 13 in cyclohexanone and for 13 in 1‐octanol in the presence of a phase‐transfer agent. The implications of these results for the design of improved extractants for radioactive waste treatment are discussed.