bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ru–η6‐benzene–phosphine complex‐catalyzed transfer hydrogenation of ketones
Authors: Wang Lei , Yang Qin , Fu Hai‐Yan , Chen Hua , Yuan Mao‐Lin , Li Rui‐Xiang 
Published: July 2011

AbstractThree Ru–η6‐benzene–phosphine complexes bearing tri‐(p‐methoxyphenyl)phosphine, triphenylphosphine and tri‐(p‐trifluoromethylphenyl)phosphine were synthesized and characterized by 31P{1H} NMR, 1H NMR, 13C{1H} NMR and elemental analyses. Complex 1 was further identified by X‐ray crystallography. These complexes exhibit good to excellent activities for the transfer hydrogenation of ketones in refluxing 2‐propanol, and the highest turnover frequency (TOF) is up to 5940 h−1. The effect of electronic factors of these complexes on the transfer hydrogenation of ketones reveals that the catalytic activity is promoted by electron‐donating phosphine and the catalyst stability is improved by electron‐withdrawing phosphine. Copyright © 2011 John Wiley & Sons, Ltd.
Cure kinetic of castor oil‐based polyurethane
Authors: Milanese Andressa Cecília , Cioffi Maria Odila Hilário , Voorwald Herman Jacobus Cornelis , Shigue Carlos Yujiro 
Published: July 2011

AbstractThis research presents the kinetic studies on the cure reactions of a new material, castor oil‐based polyurethane resin. Thermal analysis by isothermal differential scanning calorimetry was used, as a variety of factors affect its cure, including formulation and polymerization process. The kinetic reaction of this catalyzed system is described by nth order equation. Castor oil, a vegetable triglyceride, was reacted with methylene diphenyl 4,4′‐diisocyanate to produce an elastomeric matrix. The objective of this research is thermal characterization of new polyurethane that is less aggressive to humans and environment; therefore, castor oil used on the synthesis is derived from a natural and renewable resource. The activation energy measured for the castor oil‐based polyurethane resin studied in this work was about 56 kJ/mol. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Properties of flat‐pressed wood plastic composites containing fire retardants
Authors: Ayrilmis Nadir , Benthien Jan T. , Thoemen Heiko , White Robert H. 
Published: July 2011

AbstractThis study investigated physical, mechanical, and fire properties of the flat‐pressed wood plastic composites (WPCs) incorporated with various fire retardants (FRs) [5 or 15% by weight (wt)] at 50 wt % of the wood flour (WF). The WPC panels were made from dry‐blended WF, polypropylene (PP) with maleic anhydride‐grafted PP (2 wt %), and FR powder formulations using a conventional flat‐pressing process under laboratory conditions. The water resistance and strength values of the WPC panels were negatively affected by increasing the FR content as compared to the WPC panels without FR. The WPC panels incorporated with zinc borate (ZB) gave an overall best performance in both water resistance and strength values followed by the panels containing magnesium hydroxide (MH) and ammonium polyphosphate (APP). For these three FR's, the best fire resistance as measured in the cone calorimeter was obtained with the 15 wt % APP treatment and then followed by 15 wt % ZB, or 15 wt % MH formulations. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
An analysis of the educational value of low‐fidelity anatomy models as external representations
Authors: Chan Lap Ki , Cheng Maurice M.W. 
Published: July 2011

AbstractAlthough high‐fidelity digital models of human anatomy based on actual cross‐sectional images of the human body have been developed, reports on the use of physical models in anatomy teaching continue to appear. This article aims to examine the common features shared by these physical models and analyze their educational value based on the literature on cognition, learning, and external representations. A literature search on these physical models in three popular anatomy journals published over a 10‐year period from 2001 to 2010 found that all of them have low fidelity: they oftentimes do not closely resemble the regions of the human body they are representing. They include only a small number of the structures that exist in these regions of the human body and do not accurately represent the shape and surface details of these structures. However, these models strongly correspond to the human body in the spatial relationship of the represented structures, which is crucial to achieving their educational purpose of teaching three‐dimensional comprehension and anatomical reasoning. The educational value of these models includes acting as memory aids, reducing cognitive overload, facilitating problem solving, and arousing students' enthusiasm and participation. Because these models often lack a close resemblance to the human body, their use in anatomy teachingshould always be accompanied by adequate explanations to the students to establish the correspondence between the models and the parts of the human body they are representing. Anat Sci Educ. © 2011 American Association of Anatomists.
Dynamic Covalent Chemistry: A Facile Room‐Temperature, Reversible, Diels–Alder Reaction between Anthracene Derivatives and N‐Phenyltriazolinedione
Authors: Roy Nabarun , Lehn Jean‐Marie 
Published: July 2011

AbstractA series of readily accessible, dynamic Diels–Alder reactions that are reversible at room temperature have been developed between anthracene derivatives as dienes and N‐phenyl‐1,2,4‐triazoline‐3,5‐dione as the dienophile. The adducts formed undergo reversible component exchange to form dynamic libraries of equilibrating cycloadducts. Furthermore, reversible adduct formation allows temperature‐dependent modulation of the fluorescent properties of anthracene components; a feature of potential interest for the design of optodynamic polymeric materials by careful selection and manipulation of these simple dienes and dienophiles.
Chemical Modification and Organelle‐Specific Localization of Orlistat‐Like Natural‐Product‐Based Probes
Authors: Yang Peng‐Yu , Liu Kai , Zhang Chongjing , Chen Grace Y. J. , Shen Yuan , Ngai Mun Hong , Lear Martin J. , Yao Shao Q. 
Published: July 2011

AbstractOrlistat, also known as tetrahydrolipstatin (THL), is an FDA‐approved anti‐obesity drug with potential anti‐cancer activity. Previously, we developed a chemical proteomic approach, based on the Orlistat‐like probe (1a) for large‐scale identification of unknown cellular targets of Orlistat in human hepatocytes. In this article, we report the chemical synthesis and biological evaluation of an expanded set of Orlistat‐like compounds, with the intention to further dissect and manipulate potential cellular targets of Orlistat. In doing so, we carried out proteome‐wide activity‐based profiling and large‐scale pull‐down/LCMS analysis of these compounds in live HepG2 cells, and successfully identified many putative cellular targets for Orlistat and its structural analogues. By qualitatively assessing the spectra counts of potential protein hits against each of the seventeen Orlistat analogues, we obtained both common and unique targets of these probes. Our results revealed that subtle structural modifications of Orlistat led to noticeable changes in both the cellular potency and target profiles of the drug. In order to further improve the cellular activity of Orlistat, we successfully applied the well‐established AGT/SNAP‐tag technology to our cell‐permeable, benzylguanine (BG)‐containing Orlistat variant (4). We showed that the drug could be delivered and effectively retained in different sub‐cellular organelles of living cells. This strategy may provide a general and highly effective chemical tool for the potential sub‐cellular targeting of small molecule drugs.
Long-term outcome of isolated limb perfusion with tumour necrosis factor-α for patients with melanoma in-transit metastases
Authors: Deroose J P , Grünhagen D J , Van Geel A N , De Wilt J H W , Eggermont A M M , Verhoef C 
Published: July 2011

Abstract

Background
The use of tumour necrosis factor (TNF) α in isolated limb perfusion (ILP) for in-transit melanoma metastasis is not uniformly accepted. This article reports the long-term results of adding TNF-α to standard melphalan-based ILP (TM-ILP) for treatment of melanoma in-transit metastases.

Methods
Data for patients treated between 1991 and 2005 were retrieved from a prospectively maintained database. Hyperthermic ILP was performed with 1–4 mg TNF-α. With a median potential follow-up of 13 years, response rates, time to local progression and disease-specific survival were analysed in relation to standard baseline factors.

Results
Some 118 TM-ILPs were analysed in 105 patients, 54 for stage IIIA, 50 for stage IIIAB and 14 for stage IV disease. The overall response rate was 93·2 per cent; the response was complete in 67·8 per cent and partial in 25·4 per cent. The response rate was significantly influenced by stage of disease (IIIA versus IIIAB; P = 0·006). The complete response was maintained until the end of follow-up in 35 patients (33·3 per cent), and local control was achieved with one additional intervention in 12 others (11·4 per cent). Local progression occurred after 66 ILPs (55·9 per cent). Number of in-transit metastases (P = 0·008) and complete response after ILP (P &lt; 0·001) were strong prognostic factors for time to local progression. The 5-year disease-specific survival rate was 27·3 per cent; survival was positively influenced by age, stage of disease, previous ILP and complete response after ILP.

Conclusion
ILP with TNF-α may obtain long-term local control in selected patients with in-transit metastases from melanoma.
The Frataxin Homologue Fra Plays a Key Role in Intracellular Iron Channeling in Bacillus subtilis
Authors: Albrecht Alexander G. , Landmann Hannes , Nette David , Burghaus Olaf , Peuckert Florian , Seubert Andreas , Miethke Marcus , Marahiel Mohamed A. 
Published: July 2011

AbstractFrataxin homologues are important iron chaperones in eukarya and prokarya. Using a native proteomics approach we were able to identify the structural frataxin homologue Fra (formerly YdhG) of Bacillus subtilis and to quantify its native iron‐binding stoichiometry. Using recombinant proteins we could show in vitro that Fra is able to transfer iron onto the B. subtilis SUF system for iron–sulfur cluster biosynthesis. In a four‐constituents reconstitution system (including SufU, SufS, Fra and CitB) we observed a Fra‐dependent formation of a [4 Fe–4 S] cluster on SufU that could be efficiently transferred onto the target apo‐aconitase (CitB). A Δfra deletion mutant showed a severe growth phenotype associated with a broadly disturbed iron homeostasis; this indicates that Fra is a central component of intracellular iron channeling in B. subtilis.
A Palladium‐Catalyzed Multicascade Reaction: Facile Low‐Temperature Hydrogenolysis of Activated Nitriles and Related Functional Groups
Authors: Yap Aaron J. , Chan Bun , Yuen Alexander K. L. , Ward Antony J. , Masters Anthony F. , Maschmeyer Thomas 
Published: July 2011

AbstractThe facile hydrogenolysis of various nitriles, imines, and amines over Pd/C has been achieved by using straightforward and relatively mild conditions. Substrates that contain an aryl group adjacent to the nitrogen‐containing functionality were hydrogenolyzed most effectively. The stabilization of the proposed η2‐coordinated palladium intermediate by this group was partly responsible for this observation and is borne out by ab initio calculations.
Rational Design of Microporous and Mesoporous Solids for Catalysis: From the Molecule to the Reactor
Authors: Louis Benoît , Laugel Guillaume , Pale Patrick , Pereira Marcelo Maciel 
Published: July 2011

AbstractZeolitic materials are the heterogeneous catalysts that have the highest annual production and are used in numerous acid‐catalyzed reactions. Nowadays, hydrocarbon transformations, such as cracking, alkylation, and isomerization, are preferably conducted using these environmentally friendly microporous solid acids. In the general shift from homogeneous towards heterogeneous catalysis, zeolites play a key role. The rational design of these inorganic materials with highly crystalline structure is warranted both in academic and in industrial research. A proper chemical composition, a hierarchical porosity, an appropriate crystal size have, therefore, to be combined with a proper shape at the reactor level.
Flow Characteristics of Gas Permeation through a PVF Porous Tube
Authors: Zhang X. W. , Hao P. F. , Yao Z. H. 
Published: July 2011

AbstractPVF (polyvinyl formal) porous materials have attractive properties, such as noise attenuation, good structural integrity, thermal and chemical stability, high permeability and large specific surface area, for many flow‐through applications. Several characteristics of the porous material will have an impact on the permeability, and gas flow and diffusion. However, the shape and the design of the device may also have significant impact on the gas flow. A porous media model and Darcy‐Forchheimer principle were used as the basic theoretical frame. The unified governing equations were used to describe the compressible flow in and out of a PVF porous tube. A robust NND numerical scheme was used to discretize the equations and the TDBC (time‐dependent boundary conditions) were used to treat the nonreflective boundaries. Numerical simulations of an interior and exterior flow field of a PVF porous tube were completed. The detailed flow characteristics of the inner and outer flow fields of the tube were obtained. The velocity distribution of the outside of the tube compare very well with the experimental data.
Enhancement of Oily Wastewater Treatment by Ceramic Microfiltration Membranes using Powder Activated Carbon
Authors: Abbasi M. , Reza Sebzari M. , Mohammadi T. 
Published: July 2011

AbstractResults of a hybrid microfiltration‐powdered activated carbon (MF‐PAC) system for the treatment of synthetic oily wastewaters with mullite and mullite‐alumina (50 % alumina content) ceramic membranes are presented. The experiments were conducted to determine the effects of the presence of PAC on MF process performance in terms of flux decline, membrane fouling, and total organic carbon (TOC) rejection. The experimental results demonstrate that PAC addition at low concentration (200–400 ppm) increases permeate flux by 19.6 % for mullite and 61 % for mullite‐alumina MF membranes. However, high PAC concentration (1200 ppm) decreases the permeate flux by 22 % for mullite and 25 % for mullite‐alumina MF membranes. Also, TOC rejection increases from 93.8 to 97.4 % for mullite and from 89.6 to 92.4 % for mullite‐alumina MF membranes.
Numerical Simulation of Dispersed Gas/Liquid Flows in Bubble Columns at High Phase Fractions using OpenFOAM®. Part I – Modeling Basics
Authors: Marschall H. , Mornhinweg R. , Kossmann A. , Oberhauser S. , Langbein K. , Hinrichsen O. 
Published: July 2011

AbstractVarious chemical products are synthesized in processes using gas/liquid reactors with bubbly flows. Hence, there is a significant interest in a more efficient process design as well as in process intensification with a strong focus on this reactor class. However, the design of industrial gas/liquid reactors requires more detailed information about the flow structures and characteristics of two‐ or multiphase systems. The basic models for two‐fluid model simulations of dispersed gas/liquid flows in bubble columns at high gas fractions are presented.
Four‐Coordinate Trispyrazolylboratomanganese and ‐iron Complexes with a Pyrazolato Co‐ligand: Syntheses and Properties as Oxidation Catalysts
Authors: Tietz Thomas , Limberg Christian , Stößer Reinhard , Ziemer Burkhard 
Published: July 2011

AbstractA series of complexes of the type [(TpR1,R2)M(X)] (Tp=trispyrazolylborato) with R1/R2 combinations Me/tBu, Ph/Me, iPr/iPr, Me/Me and for M=Mn or Fe coordinating [PzMe,tBu]− (Pz=pyrazolato) or Cl− as co‐ligand X has been synthesised. Although the chloride complexes were very unreactive and stable in air, the pyrazolato series was far more reactive in contact with oxidants like O2 and tBuOOH. The [(TpR1,R2)M(PzMe,tBu)] complexes proved to be active pre‐catalysts for the oxidation of cyclohexene with tBuOOH, reaching turnover frequencies (TOFs) ranging between moderate and good in comparison to other manganese catalysts. Cyclohexene‐3‐one and cyclohexene‐3‐ol were always found to represent the main products, with cyclohexene oxide occasionally formed as a side product. The ratios of the different oxidation products varied with the reaction conditions: in the case of a peroxide/alkene ratio of 4:1, considerably more ketone than alcohol was obtained and cyclohexene oxide formation was almost negligible, whereas a ratio of 1:10 led to a significant increase of the alcohol proportion and to the formation of at least small amounts of the epoxide. Pre‐treatment of the dissolved [(TpR1,R2)M(PzMe,tBu)] pre‐catalysts with O2 led to product distributions and TOFs that were very similar to those found in the absence of O2, so that it may be argued that tBuOOH and O2 both lead to the same active species. The results of EPR spectroscopy and ESI‐MS suggest that the initial product of the reaction of [(TpMe,Me)Mn(PzMe,tBu)] with O2 contains a MnIII(O)2MnIV core. Prolonged exposure to O2 leads to a different dinuclear complex containing three O‐bridges and resulting in different TOFs/product distributions. Analogous findings were made for other complexes and formation of these overoxidised products may explain the deviation of the catalytic performances if the reactions are carried out in an O2 atmosphere.
Rapid computation of value and risk for derivatives portfolios
Authors: Weston Stephen , Spooner James , Racanière Sébastien , Mencer Oskar 
Published: July 2011

SUMMARYWe report new results from an on‐going project to accelerate derivatives computations. Our earlier work was focused on accelerating the valuation of credit derivatives. In this paper, we extend our work in two ways: by applying the same techniques, first, to accelerate the computation of portfolio level risk for credit derivatives and, second, to different asset classes using a different type of mathematical model, which together present challenges that are quite different to those dealt with in our earlier work. Specifically, we report acceleration over 270 times faster than a single Intel Core for a multi‐asset Monte Carlo model. We also explore the implications for risk. Copyright © 2011 John Wiley & Sons, Ltd.
Parallel pairwise statistical significance estimation of local sequence alignment using Message Passing Interface library
Authors: Agrawal Ankit , Misra Sanchit , Honbo Daniel , Choudhary Alok 
Published: July 2011

SUMMARYHomology detection is a fundamental step in sequence analysis. In the recent years, pairwise statistical significance has emerged as a promising alternative to database statistical significance for homology detection. Although more accurate, currently it is much time consuming because it involves generating tens of hundreds of alignment scores to construct the empirical score distribution. This paper presents a parallel algorithm for pairwise statistical significance estimation, called MPIPairwiseStatSig, implemented in C using MPI library. We further apply the parallelization technique to estimate non‐conservative pairwise statistical significance using standard, sequence‐specific, and position‐specific substitution matrices, which has earlier demonstrated superior sequence comparison accuracy than original pairwise statistical significance. Distributing the most compute‐intensive portions of the pairwise statistical significance estimation procedure across multiple processors has been shown to result in near‐linear speed‐ups for the application. The MPIPairwiseStatSig program for pairwise statistical significance estimation is available for free academic use at www.cs.iastate.edu~ankitag/MPIPairwiseStatSig.html. Copyright © 2011 John Wiley & Sons, Ltd.
Can new optical techniques for in vivo imaging and flow cytometry of the microcirculation benefit sickle cell disease research?
Authors: Morgan Stephen P. 
Published: July 2011

AbstractIntravital microscopy is a valuable tool for research into sickle cell disease with studies being carried out on transgenic mice and human volunteers. The method has helped to develop an explanation for sickle crises based on cell adhesion to the vascular endothelium followed by logjamming of rigid sickle cells and has stimulated much research into new treatments. In recent years there have been numerous new optical techniques developed for imaging the microcirculation and understanding the circulation of cells within the body, many of which have been further developed into in vivo flow cytometry techniques. This brief review highlights some of the progress made to date in the understanding of sickle cell disease using intravital microscopy. New techniques for imaging the microcirculation and their potential uses in understanding sickle cell disease are discussed. © 2011 International Society for Advancement of Cytometry
Basal levels of CD34 positive cells in peripheral blood differ between individuals and are stable for 18 months
Authors: Eidenschink Lisa , DiZerega Gere , Rodgers Kathy , Bartlett Mark , Wells Denise A. , Loken Michael R. 
Published: July 2011

AbstractBackground:Detection of basal levels of CD34 progenitor cells is a rare event analysis enumerating cells down to 1 cell/μl. A reproducible analytic approach was used in three independent clinical trials in which multiple sequential assays were obtained from the same individual.Methods:A 4 color panel combining, HLA‐DR, CD34, CD45, and CD11b was used in a dual platform analysis to quantify CD34 progenitor cells in peripheral blood, with quality control focused at the lowest measurements (i.e., basal levels), where assay error is greatest.Results:Repeat testing of individuals every 4 h over the course of 6 days provided a unique opportunity to assess the precision of the analytic technique and identified basal differences between individuals. In a second study, the basal levels were stable for 10 weeks while in a third study the individual differences were maintained for 18 months. This approach was then used to monitor the kinetics of mobilization of CD34 cells following G‐CSF stimulation every 4 h.Conclusions:The differences between individuals in basal levels of CD34 were shown to be a biologic constant, stable for 18 months and not a result of the variability of the assay, shown by low coefficients of variation for each individual. These results can be used to augment a quality control program by monitoring individuals over time to establish intra and inter‐laboratory assay precision. In addition, the response of six individuals to G‐CSF demonstrated differences in absolute numbers of mobilized CD34 progenitor cells but showed identical kinetics, peaking at 80–110 h. © 2011 International Clinical Cytometry Society