bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical Diversity of Volatiles of Teucrium orientale L. var. orientale, var. puberulens, and var. glabrescens Determined by Simultaneous GC‐FID and GC/MS Techniques
Authors: Özek Gulmira , Özek Temel , Dinç Muhittin , Doǧu Süleyman , Başer Kemal H. C. 
Published: June 2012

AbstractIn the present work, three varieties of Teucrium orientale, var. orientale, var. puberulens, and var. glabrescens, were collected and investigated for chemical composition of the oils. Subsequent gas chromatography (GC‐FID) and gas chromatography coupled to mass spectrometry (GC/MS) revealed high abundance of sesquiterpenes in the essential oils analyzed. All the oils contained β‐caryophyllene (22.6, 8.5, and 6.3%, resp.) and hexadecanoic acid (7.9, 12.8, and 13.1%). Germacrene D (24.6 and 33.4%) and bicyclogermacrene (6.7 and 8.5%) were found to be the main constituents of var. orientale and var. puberulens, respectively. The high percentages of β‐cubebene (26.9%), α‐cubebene (9.0%), and α‐copaene (7.2%) established the diversity of var. glabrescens. The qualitative difference between the essential oils allowed the differentiation between the varieties in agreement with the morphological observations described in Flora of Turkey for each variety studied. In addition, a cluster analysis of twelve Teucrium taxa based on the essential‐oil composition has been carried out. Hovewer, the analysis did not clearly reflect the infrageneric classification of the genus, it largely confirmed the relationships between the infraspecific taxa of Teucrium orientale and T. chamaedrys.
Molecular‐Dynamics Simulation of Dioxygen Egress from 12/15‐LipoxygenaseArachidonic Acid Complex
Authors: Pietra Francesco 
Published: June 2012

AbstractExtensive random‐acceleration molecular‐dynamics (RAMD) simulations of the egress of dioxygen (O2) from a model of rabbit 12/15‐lipoxygenasearachidonic acid complex disclosed several exit portals in addition to those previously described from implicit ligand sampling calculations and limited MD simulations.
Population Variability of Nonacosan‐10‐ol and n‐Alkanes in Needle Cuticular Waxes of Macedonian Pine (Pinus peuceGriseb.)
Authors: Nikolić Biljana , Tešević Vele , Đorđević Iris , Todosijević Marina , Jadranin Milka , Bojović Srdjan , Marin Petar D. 
Published: June 2012

AbstractThis is the first report on population variability of nonacosan‐10‐ol and n‐alkanes in needle epicuticular waxes of Macedonian pine (Pinus peuce Griseb.) Hexane extracts of needle samples, originating from two natural populations in Montenegro (Zeletin and Sjekirica) and from one population in Serbia (Mokra Gora) were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The amount of nonacosan‐10‐ol varied individually from 41.3 to 72.31% (average 55.9%), with the Sjekirica population being statistically divergent (64.4% on average). The results showed n‐alkanes in epicuticular waxes ranging from C18 to C33. The most abundant alkanes were C29, C25, C27, and C23 (15.5, 11.1, 10.6, and 10.5% on average, resp.). The carbon preference index of Pinus peuce ranged from 1.0 to 4.3 (1.9 on average). Average chain length ranged from 18.4 to 27.7 (average 25.7). A high level of inidividual quantitative variation in all of these hydrocarbon parameters was also detected. These results were compared with published data on other species from the Pinus genus.
Cumene Hydroperoxide Hydrogenation on a Pd/Al2O3 Catalyst in a Trickle Bed Reactor – Kinetics of Hydrogenation and Deactivation
Authors: Ma Y. , Zhu Q.‐C. 
Published: June 2012

AbstractLiquid‐phase hydrogenation using a Pd/Al2O3 catalyst provides a potential technique for the reduction of cumene hydroperoxide (CHP) to α‐cumyl alcohol (CA). In this paper, CHP hydrogenation was carried out in a cocurrent downflow trickle‐bed reactor over a wide range of reaction conditions to study the reaction and deactivation kinetics. The proposed intrinsic rate expression for CHP hydrogenation is based on an Eley‐Rideal mechanism that accounts for an irreversible surface reaction between the absorbed CHP with nonabsorbed hydrogen molecules. During CHP hydrogenation, an exponential decay in activity of the Pd/Al2O3 catalyst and the presence of residual activity were observed. A kinetic deactivation model with residual activity was developed. Based on reaction and deactivation kinetics, catalyst deactivation was attributed to oxidation of the catalyst surface by CHP. The presence of residual activity was due to the partial reduction of oxidized catalyst surface by hydrogen.
Consecutive Intermolecular Reductive Hydroamination: Cooperative Transition‐Metal and Chiral Brønsted Acid Catalysis
Authors: Fleischer Steffen , Werkmeister Svenja , Zhou Shaolin , Junge Kathrin , Beller Matthias 
Published: June 2012

AbstractEnantiomerically pure chiral amines are of increasing importance and commercial value in the fine chemical, pharmaceutical, and agrochemical industries. Here, we describe the straightforward synthesis of chiral amines by combining the atom‐economic and environmentally friendly hydroamination of alkynes with an enantioselective hydrogenation of in situ generated imines by using inexpensive hydrogen. By following this novel approach, a wide range of terminal alkynes can be reductively hydroaminated with primary amines including alkyl‐, and arylalkynes as well as aryl and heteroaryl amines. Excellent yields and selectivities up to 94 % ee and 96 % isolated yield were obtained.
A Nano‐Fibrillated Mesoporous Carbon as an Effective Support for Palladium Nanoparticles in the Aerobic Oxidation of Alcohols “on Pure Water”
Authors: Karimi Babak , Behzadnia Hesam , Bostina Mihnea , Vali Hojatollah 
Published: June 2012

AbstractA novel nano‐fibrillated mesoporous carbon (IFMC) was successfully prepared via carbonization of the ionic liquid 1‐methyl‐3‐phenethyl‐1H‐imidazolium hydrogen sulfate (1) in the presence of SBA‐15. The material was shown to be an efficient and unique support for the palladium nanoparticle (PdNP) catalyst Pd@IFMC (2) in aerobic oxidation of heterocyclic, benzylic, and heteroatom containing alcohols on pure water at temperatures as low as 40 °C for the first time and giving almost consistent activities and selectivities within more than six reaction runs. The catalyst has also been employed as an effective catalyst for the selective oxidation of aliphatic and allylic alcohols at 70–80 °C. The materials were characterized by X‐ray photoelectron spectroscopy (XPS), N2 adsorption–desorption analysis, transmission electron microscopy (TEM), and electron tomography (ET). Our compelling XPS and ET studies showed that higher activity of 2 compared to Pd@CMK‐3 and Pd/C in the aerobic oxidation of alcohols on water might be due to the presence of nitrogen functionalities inside the carbon structure and also the fibrous nature of our materials. The presence of a nitrogen heteroatom in the carboneous framework might also be responsible for the relatively uniform and nearly atomic‐scale distribution of PdNPs throughout the mesoporous structure and the inhibition of Pd agglomeration during the reaction, resulting in high durability, high stability, and recycling characteristics of 2. This effect was clearly confirmed by comparing the TEM images of the recovered 2 and Pd@CMK‐3.
Synthetic Studies toward C‐Glucosidic Ellagitannins: A Biomimetic Total Synthesis of 5‐O‐Desgalloylepipunicacortein A
Authors: Malik Gaëlle , Natangelo Anna , Charris Jaime , Pouységu Laurent , Manfredini Stefano , Cavagnat Dominique , Buffeteau Thierry , Deffieux Denis , Quideau Stéphane 
Published: June 2012

AbstractC‐glucosidic ellagitannins constitute a subclass of bioactive polyphenolic natural products with strong antioxidant properties, as well as promising antitumoral and antiviral activities that are related to their capacity to interact with both functional and structural proteins. To date, most synthetic efforts toward ellagitannins have concerned glucopyranosic species. The development of a synthetic strategy to access C‐glucosidic ellagitannins, whose characteristic structural feature includes an atropoisomeric hexahydroxydiphenoyl (HHDP) or a nonahydroxyterphenoyl (NHTP) unit that is linked to an open‐chain glucose core by a C‐aryl glucosidic bond, is described herein. The total synthesis of the biarylic HHDP‐containing 5‐O‐desgalloylepipunicacortein A (1 β) was achieved by either using the natural ellagic acid bis‐lactone as a precursor of the requested HHDP unit or by implementing an atroposelective intramolecular oxidative biarylic coupling to forge this HHDP unit. Both routes converged in the penultimate step of this synthesis to enable a biomimetic formation of the key C‐aryl glucosidic bond in the title compound.
ortho‐Quinone Methides in Natural Product Synthesis
Authors: Willis Nicky J. , Bray Christopher D. 
Published: June 2012

Abstractortho‐Quinone methides (o‐QMs) are emerging as highly useful intermediates, the inherent reactivity of which can be used in linchpin reactions for the construction of complex natural products. This review encompasses the major contributions in this field, exemplifying the major strategies and reactivity modes which can be applied.
Organophosphorus Reagents in Organocatalysis: Synthesis of Optically Active α‐Methylene‐δ‐lactones and δ‐Lactams
Authors: Albrecht Anna , Morana Fabio , Fraile Alberto , Jørgensen Karl Anker 
Published: June 2012

AbstractIn this paper we describe new asymmetric, catalytic strategies for the synthesis of biologically important α‐methylene‐δ‐lactones and δ‐lactams. The elaborated protocols utilize iminium‐ion‐mediated Michael addition of trimethyl phosphonoacetate to α,β‐unsaturated aldehydes catalyzed by (S)‐(−)‐α,α‐diphenyl‐2‐pyrrolidinemethanol trimethylsilyl ether as the key step. Enantiomerically enriched Michael adducts are employed in three different reaction pathways. Transformation into α‐methylene‐δ‐lactones is realized by a sequence of reactions involving chemoselective reduction of the aldehyde, followed by a trifluoroacetic acid (TFA)‐mediated cyclization and Horner–Wadsworth–Emmons olefination of formaldehyde. On the other hand, indolo[2, 3‐a]quinolizine‐framework‐containing products can be accessed when enantiomerically enriched Michael adducts are employed in a Pictet–Spengler reaction with tryptamine, followed by Horner–Wadsworth–Emmons olefination. Finally, reductive amination of the Michael adducts by using methylamine and Horner–Wadsworth–Emmons olefination of formaldehyde is demonstrated to give α‐methylene‐δ‐lactams. The developed strategies can be realized without the purification of intermediates, thus greatly increasing their practicality.
Detection of knee‐joint motions using two linear accelerometers for pendulum test
Authors: Kusuhara Toshimasa , Jikuya Kazuaki , Nakamura Takao , Michinishi Hiroyuki , Yamamoto Yoshitake , Okamoto Takuji 
Published: June 2012

AbstractIn order to solve nonlinear differential equations concerning spinal stretch reflexes in the pendulum test, mutually synchronized values of the angle, angular velocity, and angular acceleration in the knee joint are frequently used as initial values. In this study, we propose a method which can detect both the angle and angular acceleration in the knee joint at the same time by simple operations on the outputs of two accelerometers. The principle of knee‐joint motion detection, the evaluation of amplitude accuracy in the measured waveforms, and the evaluation of synchronization accuracy are successively described. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(7): 41–48, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11383
Different Inertness of Titanocene [Cp2Ti] and Decamethyltitanocene [Cp*2Ti] in Reactions with N,N‐Bis(trimethylsilyl)sulfurdiimide – Elimination of Tetramethyl­fulvene and Formation of Half‐Titanocene Complexes
Authors: Kaleta Katharina , Kessler Monty , Beweries Torsten , Arndt Perdita , Spannenberg Anke , Rosenthal Uwe 
Published: June 2012

AbstractThe reaction of the titanocene alkyne complex [Cp*2Ti(η2‐Me3SiC2SiMe3)] (1) (Cp* = η5‐pentamethylcyclopentadienyl) with N,N‐bis(trimethylsilyl)sulfurdiimide (2) results in the formation of 1,2,3,4‐tetramethylfulvene (3) as well as three titanium complexes 4, 5 and 6. During the reaction, formal elimination of one Cp* ligand induces a series of C–H and N–S bond activation steps, thus yielding the products. The molecular structures of complex 5 and of the free fulvene were determined by X‐ray crystallographic analysis. Evidently, in these reactions [Cp*2Ti] is less stable than [Cp2Ti]; a possible reason was found to be the well‐known intramolecular C–H activation yielding the tautomeric tetramethylfulvene hydride species, from which 1,2,3,4‐tetramethylfulvene (3) can dissociate.
Measurements of Pore Size Distribution, Porosity, Effective Oxygen Diffusivity, and Tortuosity of PEM Fuel Cell Electrodes
Authors: Yu Z. , Carter R. N. , Zhang J. 
Published: June 2012

AbstractThe characterization of proton exchange membrane fuel cell electrodes is essential for understanding the electrode performance. In this paper, mercury intrusion porosimetry and the nitrogen adsorption method were used to measure pore size distributions and porosities (ϵ) of various electrodes, which were made with either platinum supported on amorphous carbon (Pt/VA) or platinum supported on graphitized carbon (Pt/VG), and had ionomer‐to‐carbon weight ratios (I/C) of 0.5, 1.0, and 1.5. The oxygen effective diffusivity ($ D_{{\rm O}_2}^{\rm eff} $) in electrodes was measured as a function of relative humidity (RH) in an apparatus that was previously described [Z. Yu, R. N. Carter, J. Power Sources 195 (2010) 1079–1084]. The tortuosity of electrodes at the dry condition (80 °C and 0% RH) was then determined from the measured porosities and $ D_{{\rm O}_2}^{\rm eff} $. For a given catalyst, as the I/C ratio increased, it was found that the electrode's mean pore size, porosity, and $ D_{{\rm O}_2}^{\rm eff} $ all decreased, but the tortuosity increased. For a given I/C ratio, the Pt/VA electrode exhibited larger mean pore size, larger porosity, larger $ D_{{\rm O}_2}^{\rm eff} $, and smaller tortuosity compared with the Pt/VG electrode. The contrast between Pt/VA and Pt/VG electrodes with the same I/C ratio indicates different ionomer distribution on the catalyst surface.
Novel Route to 4‐(Adamantan‐1‐yl)quinoline Derivatives Based on the Friedländer Condensation
Authors: Kozubková Zuzana , Rouchal Michal , Nečas Marek , Vícha Robert 
Published: June 2012

Abstract2,3,4‐Trisubstituted quinolines, substituted with adamantan‐1‐yl or (adamantan‐1‐yl)methyl in the 4‐position, were prepared from the corresponding admantan‐1‐yl 2‐aminophenyl ketones or admantan‐1‐ylmethyl 2‐aminophenyl ketones and ketones with an α‐CH2 group. These reactions were carried out under neat conditions or in toluene, and the products were obtained in moderate‐to‐excellent yields. The scope and limitations of the examined procedures are discussed. All new compounds are fully characterized by IR and NMR spectroscopy and mass spectrometry. The molecular structures of five new quinolines, obtained via single‐crystal X‐ray diffraction analyses, are discussed.
Successful therapeutic vaccination with integrase defective lentiviral vector expressing nononcogenic human papillomavirus E7 protein
Authors: Grasso Felicia , Negri Donatella R.M. , Mochi Stefania , Rossi Alessandra , Cesolini Armando , Giovannelli Andrea , Chiantore Maria Vincenza , Leone Pasqualina , Giorgi Colomba , Cara Andrea 
Published: June 2012

AbstractPersistent infection with high risk genotypes of human papillomavirus (HPV) is the cause of cervical cancer, one of most common cancer among woman worldwide, and represents an important risk factor associated with other anogenital and oropharyngeal cancers in men and women. Here, we designed a therapeutic vaccine based on integrase defective lentiviral vector (IDLV) to deliver a mutated nononcogenic form of HPV16 E7 protein, considered as a tumor specific antigen for immunotherapy of HPV‐associated cervical cancer, fused to calreticulin (CRT), a protein able to enhance major histocompatibility complex class I antigen presentation (IDLV‐CRT/E7). Vaccination with IDLV‐CRT/E7 induced a potent and persistent E7‐specific T cell response up to 1 year after a single immunization. Importantly, a single immunization with IDLV‐CRT/E7 was able to prevent growth of E7‐expressing TC‐1 tumor cells and to eradicate established tumors in mice. The strong therapeutic effect induced by the IDLV‐based vaccine in this preclinical model suggests that this strategy may be further exploited as a safe and attractive anticancer immunotherapeutic vaccine in humans.
Simvastatin‐loaded macroporous calcium phosphate cement: Preparation, in vitro characterization, and evaluation of in vivo performance
Authors: Yin Han , Li Yong‐Gang , Si Meng , Li Jian‐Min 
Published: June 2012

AbstractThe aim of our study was to construct macroporous calcium phosphate bone cements (CPCs) with enhanced osteogenic potential. For this purpose, 300 mM sodium dodecyl sulfate (SDS) as an air‐entraining agent was added to the liquid phase and 1, 5, and 10% simvastatin (SIM) was homogenized with the solid phase. The physical and mechanical characteristics of the test samples were investigated. Biological properties of the new CPCs were examined after intramuscular and endosteal implantation in rabbits. The introduction of SDS produced interconnected macropores and did not significantly affect initial setting time, transformation of solid phase to hydroxyapatite, and biocompatibility of CPCs. Large amounts (10 wt %) of SIM could decrease the compressive strength and induce severe muscular necrosis and inflammatory reaction. Small amounts (1 wt %) of SIM were compatible with the CPCs did not affect the physico‐chemical properties or biocompatibility and were sufficient to enhance the osteogenic potential of macroporous CPCs. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:2991–3000, 2012.
An analysis of polymer type and chain length for use as a biological composite graft extender in impaction bone grafting: A mechanical and biocompatibility study
Authors: Tayton Edward , Fahmy Sherif , Purcell Matthew , Aarvold Alexander , Smith James O. , Kalra Spandan , Briscoe Adam , Lanham Stuart , Howdle Steven , Shakesheff Kevin , Dunlop Douglas G. , Oreffo Richard O. C. 
Published: June 2012

AbstractImpaction bone grafting (IBG) with human allograft remains the preferred approach for replacement of lost bone stock during revision hip surgery. Associated problems include cost, disease transmission, and stem subsidence. Synthetic grafts are therefore appealing, and ideally display similar mechanical characteristics as allograft, but with enhanced ability to form de novo bone. High and low molecular weight forms of three different polymers [poly(DL‐lactide) (PDLLA), poly(DL‐lactide‐co‐glycolide) (PDLLGA), and poly(ε‐caprolactone) (PCL)] were milled, impacted into discs, and then examined in a shear testing rig, in comparison to allograft. In addition, skeletal stem cells (SSCs) were combined with each of the milled polymers, followed by impaction and examination for cell viability and number, via fluorostaining and biochemical assays. The shear strengths of high/low mwt PDLLA, and high/low mwt PDLLGA were significantly higher than allograft (p < 0.01). High/low mwt PCL had significantly lower shear strengths (p < 0.01). WST‐1 assay and fluorstaining indicated significantly increased cell viability on high mwt PDLLA and high mwt PDLLGA over allograft (p < 0.05). Mechanical and biochemical analysis indicated improved properties of high mwt PDLLA and high mwt PDLLGA over allograft. This study indicates the potential of these polymers for use as substitute human allograft, creating a living composition with SSC for application in IBG. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3211–3219, 2012.
Novel antiosteoclastogenic activity of phloretin antagonizingRANKL‐induced osteoclast differentiation of murine macrophages
Authors: Kim Jung‐Lye , Kang Min‐Kyung , Gong Ju‐Hyun , Park Sin‐Hye , Han Seon‐Young , Kang Young‐Hee 
Published: June 2012

ScopeBone‐remodeling imbalance resulting in more bone resorption than bone formation is known to cause skeletal diseases such as osteoporosis. Phloretin, a natural dihydrochalcone compound largely present in apple peels, possesses antiphotoaging, and antiinflammatory activity.Methods and resultsPhloretin inhibited receptor activator of NF‐κB ligand (RANKL)‐induced formation of multinucleated osteoclasts and diminished bone resorption area produced during the osteoclast differentiation process. It was also found that ≥10 μM phloretin reduced RANKL‐enhanced tartrate‐resistance acid phosphatase activity and matrix metalloproteinase‐9 secretion in a dose‐dependent manner. The phloretin treatment retarded RANKL‐induced expression of carbonic anhydrase II, vacuolar‐type H+‐ATPase D2 and β3 integrin, all involved in the bone resorption. Furthermore, submicromolar phloretin diminished the expression and secretion of cathepsin K elevated by RANKL, being concurrent with inhibition of TRAF6 induction and NF‐κB activation. RANKL‐induced activation of nuclear factor of activated T cells c1 (NFATc1) and microphthalmia‐associated transcription factor was also suppressed by phloretin.ConclusionThese results demonstrate that the inhibition of osteoclast differentiation and bone resorption by phloretin entail a disturbance of TRAF6‐NFATc1‐NF‐κB pathway triggered by RANKL. Therefore, phloretin may be a potential therapeutic agent targeting osteoclast differentiation and bone resorption in skeletal diseases such as osteoporosis.
Human brain imaging at 9.4 T using a tunable patch antenna for transmission
Authors: Hoffmann Jens , Shajan G. , Budde Juliane , Scheffler Klaus , Pohmann Rolf 
Published: June 2012

AbstractFor human brain imaging at ultrahigh fields, the traveling wave concept can provide a more uniform B1+ field over a larger field of view with improved patient comfort compared to conventional volume coils. It suffers, however, from limited transmit efficiency and receive sensitivity and is not readily applicable in systems where the radiofrequency shield is too narrow to allow for unattenuated wave propagation. Here, the near field of a capacitively adjustable patch antenna for excitation is combined with a receive‐only array at 9.4 T. The antenna is designed in compact size and placed in close proximity to the subject to improve the transmit efficiency in narrow bores. Experimental and numerical comparisons to conventional microstrip arrays reveal improved B1+ homogeneity and longitudinal coverage, but at the cost of elevated local specific absorption rate. High‐resolution functional and anatomical images demonstrate the use of this setup for in vivo human brain imaging at 9.4 T. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.