bluuebunny/crossref_metadata_2025 huggingface dataset:
In Situ High Temperature X‐Ray Diffraction Reveals Residual Stress Depth‐Profiles in Blasted TiN Hard Coatings
Authors: Bartosik M. , Pitonak R. , Keckes J.
Published: January 2011

High temperature X‐ray diffraction (XRD) is used to characterize residual stress depth‐profiles and volume‐averaged residual stresses in blasted 9 µm thick TiN coatings on WC/Co substrates in the temperature range of 25–1100 °C using a dedicated high temperature attachment from Anton Paar GmbH. Room temperature measurements reveal that the blasting process changes the almost constant tensile residual stress of 560 MPa across the coating to compressive stress which decreases exponentially within the coating surface region of 1–3 µm. The magnitude of the compressive stresses is dependent on the particle pressure used during the blasting process. Heating up results in rapid compressive stress relaxation already at relatively low temperatures and is accompanied by relaxation of stresses of II and III order. During cooling down from 1100 °C, tensile residual stresses are formed. After reaching the original stress value of about 560 MPa, the tensile stresses do not increase upon cooling anymore but are relaxed by cracks. The analysis of diffraction peaks shows that blasting results in anisotropic nano‐structural changes in the coating surface. In summary, the approach documents that HT‐XRD can provide important insights into the high temperature behavior of engineering components.
Behavioral response of a chimpanzee mother toward her dead infant
Authors: Cronin Katherine A. , van Leeuwen Edwin J.C. , Mulenga Innocent Chitalu , Bodamer Mark D.
Published: January 2011

The mother–offspring bond is one of the strongest and most essential social bonds. Following is a detailed behavioral report of a female chimpanzee 2 days after her 16‐month‐old infant died, on the first day that the mother is observed to create distance between her and the corpse. A series of repeated approaches and retreats to and from the body are documented, along with detailed accounts of behaviors directed toward the dead infant by the mother and other group members. The behavior of the mother toward her dead infant not only highlights the maternal contribution to the mother–infant relationship but also elucidates the opportunities chimpanzees have to learn about the sensory cues associated with death, and the implications of death for the social environment. Am. J. Primatol. 73:415–421, 2011. © 2011 Wiley‐Liss, Inc.
Highly efficient amine‐based catalytic system for room temperature Suzuki–Miyaura reactions of aryl halides with arylboronic acids
Authors: Das Pankaj , Sarmah Chandan , Tairai Archana , Bora Utpal
Published: January 2011

An in situ‐generated catalytic system based on PdCl2 and primary amine‐based ligand exhibited excellent activity (up to 98% isolated yield) in the Suzuki–Miyaura cross‐coupling reactions of aryl bromides with arylboronic acids in water, at room temperature, without any additive. The efficiencies of the ligands follow the order: (C6H5)3CNH2 > C6H5CH2 NH2 > C6H5 NH2 > C6H11 NH2, which is in accordance with the palladacycle forming capacity of the respective ligands. Moderate‐to‐good yields (up to 78% isolated yield) of the coupling products were also obtained with less reactive aryl chlorides as substrates at room temperature in isopropanol using an alternative protocol based on Pd(OAc)2 and (C6H5)3CNH2. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis, characterization and cytotoxic activity of new diorganotin(IV) complexes of N‐(3,5‐dibromosalicylidene)tryptophane
Authors: Tian Laijin , Liu Xicheng , Zheng Xiaoliang , Sun Yuxi , Yan Dongmei , Tu Linglan
Published: January 2011

Four new diorganotin(IV) complexes of N‐(3,5‐dibromosalicylidene)tryptophane, R2Sn[3,5‐Br2‐2‐OC6H2CHNCH(CH2Ind)COO] [Ind = 3‐indolyl; R = Et (1); n‐Bu (2); Cy (3); Ph (4)], were synthesized and characterized by elemental analysis and IR, NMR (1H, 13C and 119Sn) spectra. The crystal structures of complexes 1–3 were determined by X‐ray single crystal diffraction. The tin atom is five‐coordinated and its coordination geometry is best described as an intermediate between trigonal bipyramidal and square pyramidal. Intermolecular weak interactions in the complexes 1–3 connect molecules into a one‐dimensional helical chain and a two‐dimensional array. The dibutyltin complex 2 has potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complex 1 displays weak cytotoxic activity. Copyright © 2011 John Wiley & Sons, Ltd.
Oppression of the different: impact and treatment
Authors: Campbell David B.
Published: January 2011

This paper explores the psychological impact of oppressive social forces among those with personal differences and delineates the affective and cognitive patterns that can unfold as a result. Recommendations for clinicians who treat patients with social/personal differences are offered. Copyright © 2011 John Wiley & Sons, Ltd.
Energetic trade‐offs between brain size and offspring production: Marsupials confirm a general mammalian pattern
Authors: Isler Karin
Published: January 2011

Recently, Weisbecker and Goswami presented the first comprehensive comparative analysis of brain size, metabolic rate, and development periods in marsupial mammals. In this paper, a strictly energetic perspective is applied to identify general mammalian correlates of brain size evolution. In both marsupials and placentals, the duration or intensity of maternal investment is a key correlate of relative brain size, but here I show that allomaternal energy subsidies may also play a role. In marsupials, an energetic constraint on brain size in adults is only revealed if we consider both metabolic and reproductive rates simultaneously, because a strong trade‐off between encephalization and offspring production masks the positive correlation between basal metabolic rate and brain size in a bivariate comparison. In conclusion, starting from an energetic perspective is warranted to elucidate relations between ecology, social systems, life history, and brain size in all mammals.
Alkaloid Diversity in Galanthus elwesii and Galanthus nivalis
Authors: Berkov Strahil , Bastida Jaume , Sidjimova Borjana , Viladomat Francesc , Codina Carles
Published: January 2011

Seventy alkaloids of galanthamine, lycorine, homolycorine, tazettine, haemanthamine, narciclasine, and tyramine types were detected by GC/MS in 25 Galanthus elwesii and seven Galanthus nivalis populations, collected from different locations in Bulgaria. Intraspecies diversity in the alkaloid profiles regarding the main alkaloid types (chemotypes) was observed. Tyramine‐type protoalkaloids (namely, hordenine and its derivatives) were dominant in 19 populations of G. elwesii. In other populations of G. elwesii, the plants accumulated mainly homolycorine‐, lycorine‐, and galanthamine‐type alkaloids. The alkaloid profiles of G. nivalis were dominated by narciclasine‐, galanthamine‐, lycorine‐, haemanthamine‐, or tazettine‐type compounds. Geographical distribution of chemotypes indicated a relationship between populations, since adjacent populations often displayed similar alkaloid profiles. The results from year‐to‐year sampling and transplantation experiments imply genetic determination of alkaloid synthesis in the two studied species of Galanthus.
Four New Asterosaponins, Hippasteriosides A – D, from the Far Eastern Starfish Hippasteria kurilensis
Authors: Kicha Alla A. , Kalinovsky Anatoly I. , Ivanchina Natalia V. , Malyarenko Timofey V. , Dmitrenok Pavel S. , Ermakova Svetlana P. , Stonik Valentin A.
Published: January 2011

Four new sulfated steroidal glycosides (asterosaponins), hippasteriosides A–D (1–4, resp.), were isolated from the alcoholic extract of the Far Eastern starfish Hippasteria kurilensis, collected in the Sea of Okhotsk near Kuril Islands. Compounds 1–4 were determined to contain the same unprecedented hexasaccharide moiety, β‐D‐xylopyranosyl‐(1→3)‐β‐D‐fucopyranosyl‐(1→2)‐β‐D‐quinovopyranosyl‐(1→4)‐[β‐D‐quinovopyranosyl‐(1→2)]‐β‐D‐xylopyranosyl‐(1→3)‐β‐D‐quinovopyranosyl, linked to C(6) of 3‐O‐sulfonylated steroidal aglycons, which differ from each other in their side‐chain structures. Structures 1–4 were elucidated by extensive NMR and MS techniques, and chemical transformations. Not all the asterosaponins show a prominent cytotoxic activity against human colon tumor HT‐29 cells, but some of them, especially compound 4 demonstrate a remarkable inhibition of the HT‐29 colony formation in soft‐agar clonogenic assay, suggesting its anticancerogenic properties.
Solid‐Phase Microextraction (SPME) Analysis of Six Italian Populations of Ephedra nebrodensisTineo ex Guss. subsp. nebrodensis
Authors: Maggi Filippo , Nicoletti Marcello , Petitto Valentina , Sagratini Gianni , Papa Fabrizio , Vittori Sauro
Published: January 2011

Headspace solid‐phase microextraction (HS‐SPME) coupled with GC/FID and GC/MS was applied for the first time in the analysis of the volatile fraction of an Ephedra species. Notably, six Italian populations (Marche, Abruzzo, and Sardinia) of Ephedra nebrodensis subsp. nebrodensis, covering almost the entire Italian area, were investigated to examine the chemical variability and to support the taxonomy of the species. A fiber screening with polymethylsiloxane (PDMS), CarboxenTM/polymethylsiloxane (CAR/PDMS), and polymethylsiloxane/divinylbenzene (PDMS/DVB) coatings, together with an optimization of the extraction conditions were carried out before analysis of the six populations. A total of 119 volatiles were identified in the headspace of different samples, accounting for 63.35–100.00% of the total volatiles. A great variability was found in the qualitative composition of different samples, since only 18 components were in common among all populations. The headspace composition was dominated by sesquiterpene hydrocarbons (52.30–88.32%), with β‐maaliene (traces–7.49%), β‐patchoulene (traces–1.29%), β‐panasinsene (traces–6.85%), α‐isocomene (traces–31.25%), α‐trans‐bergamotene (traces–6.95%), alloaromadendrene (traces–33.20%), α‐acoradiene (traces–9.41%), and γ‐muurolene (0.61–16.33%) being the most abundant constituents. Noteworthy is the occurrence in a sample of two major unknown sesquiterpenes, one hydrocarbon (24.49%, RI: 1396) and one oxygenated compound (10.37%, RI: 1591), whose mass spectra were reported for the first time. Multivariate chemometric techniques, such as cluster analysis (CA) and principal component analysis (PCA), were used to characterize the samples according to the geographical origin.
On the Mechanism of Eukaryotic Cell Penetration by α‐ and β‐Oligoarginines – Targeting Infected Erythro­cytes
Authors: Kamena Faustin , Monnanda Bopanna , Makou Danielle , Capone Stefania , Patora‐Komisarska Krystyna , Seebach Dieter
Published: January 2011

Fluorescein‐labeled α‐ and β‐octaarginine amides were synthesized. The route, by which these oligoarginine (OA) derivatives enter cells (hepatocytes, fibroblasts, macrophages), was investigated by confocal fluorescence microscopy. Comparisons (by co‐localization experiments) with compounds of known penetration modes revealed that the β‐octaarginine amide also uses multiple pathways to enter cells. There was no difference between the α‐ and the β‐OAs. Like other cell‐penetrating peptides (CPPs), the β‐octaarginine eventually winds up in the nucleoli of the cell nuclei (cf. Chem. Biodiversity, 2004, 1, 65). Surprisingly, there was no entry of α‐ or β‐OA into intact and healthy human erythrocytes (which do not possess a nucleus). Blood cells infected by Plasmodium falciparum (malaria parasite) were, however, entered readily, and the OAs went all the way through a couple of membranes into the parasite. The potential of these results for delivering specific antimalarial drugs directly into the parasite is discussed.
Enzymatic Dynamic Kinetic Resolution of Oxazinones: A New Approach to Enantiopure β2‐Amino Acids
Authors: Berkessel Albrecht , Jurkiewicz Ilona , Mohan Resmi
Published: January 2011

In the presence of Candida antarctica lipase B, the alcoholytic ring opening of 5‐substituted oxazinones proceeds as kinetic resolution (KR) and affords N‐acyl β2‐amino acid esters in up to 96 % ee, the remaining oxazinones were obtained in up to 99 % ee. In the presence of triethylamine as racemization catalyst, the enzyme‐catalyzed alcoholytic oxazinone opening proceeds as dynamic kinetic resolution (DKR), affording quantitative yields of N‐protected β2‐amino acid esters in high enantiomeric purity (up to 96 % ee). N,C‐double deprotection to afford the β2‐amino acid can be effected without loss of enantiopurity.
pH‐Switchable Inversion of the Metal‐Centered Chirality of Metallabenzenes: Opposite Stereodynamics in Reactions of Ruthenabenzene with L‐ and D‐Cysteine
Authors: Lin Ran , Zhang Hong , Li Shunhua , Chen Leiqi , Zhang Weiguang , Wen Ting Bin , Zhang Hui , Xia Haiping
Published: January 2011

We report herein the first study on the chemical interaction between metallabenzenes and bioactive molecules. Due to its unique stereoelectronic activities, a phenanthroline‐derived ruthenabenzene [Ru{CHC(PPh3)CHC(PPh3)CH}Cl(C12H8N2)(PPh3)]Cl2 (1) selectively binds cysteine in aqueous solution at physiological pH and then undergoes a dynamic inversion of configuration at the Ru center. The structure of the L‐cysteine‐binding product of 1 has been determined by means of X‐ray diffraction. The replacement of the L‐cysteine with the D form results in an inverted stereodynamic effect. Furthermore, the inversion process of the Ru‐centered configuration could be conveniently controlled by a simple pH adjustment. This is attributed to the significant influence of a special intramolecular electrostatic interaction on the dynamic epimerization process of the cysteine‐binding product.
Synthesis of a [2]Rotaxane Incorporating a “Magic Sulfur Ring” by the Thiol‐Ene Click Reaction
Authors: Zheng Haiyan , Li Yuliang , Zhou Chunjie , Li Yongjun , Yang Wenlong , Zhou Weidong , Zuo Zicheng , Liu Huibiao
Published: January 2011

The mild and highly efficient thiol‐ene click reaction has been used to construct a rotaxane incorporating dibenzo‐24‐crown‐8 (DB24C8) and a dibenzylammonium‐derived thread in high yield under the irradiation of UV light. A rotaxane containing a disulfide linkage in the macrocycle was also synthesized by the thiol‐ene click reaction. It has been demonstrated that the formation of the [2]rotaxane with the disulfide bond in the macrocycle occurs by a mechanism that is different to the threading‐followed‐by‐stoppering process. The successful construction of a rotaxane directly from its constituent components, the macrocycle containing a disulfide linkage and the dibenzylammonium hexafluorophosphate salt, suggests that the space within the macrocycle incorporating the disulfide linkage is smaller than the phenyl unit and a plausible reaction mechanism has been proposed as follows: A small amount of the initiator forms two radicals upon the absorption of UV irradiation; the radicals act as a “key” to “unlock” the disulfide bond in the macrocycle. The resulting crown ether like moiety in the macrocycle is clipped around the ammonium ion center in the dumb‐bell‐shaped compound. The [2]rotaxane is generated upon recombination of the disulfide linkage.
Rhythm Control for Management of Patients With Atrial Fibrillation: Balancing the Use of Antiarrhythmic Drugs and Catheter Ablation
Authors: Viles‐Gonzalez Juan F. , Fuster Valentin , Halperin Jonathan , Calkins Hugh , Reddy Vivek Y.
Published: January 2011

Antiarrhythmic drug (AAD) therapy may be beneficial for patients with symptoms attributable to atrial fibrillation despite adequate rate control. The limited long‐term efficacy of AAD and the relatively large proportion of patients discontinuing therapy because of side effects led to the development of nonpharmacological therapies to achieve rhythm control. Pressing questions remain about the effect of ablation therapy on long‐term patient outcomes. Based on recent clinical trials and meta‐analyses, ablation appears more effective and possibly safer than AAD for long‐term maintenance of sinus rhythm in selected patients, but the evidence is insufficient to recommend ablation in preference to drug therapy as the first AAD therapy for the majority of patients in whom a rhythm control strategy is justified. Herein, we review the most current evidence supporting the use of AAD and catheter ablation in atrial fibrillation. Copyright © 2011 Wiley Periodicals, Inc.

Hugh Calkins, MD is a consultant to Sanofi Aventis, Biosense Webster, and Medtronic, and he receives research support from Biosense Webster and Medtronic. All other authors have no conflicts of interest to disclose.
Offline enforcement of contracts for high‐performance computing
Authors: Damevski Kostadin
Published: January 2011

Design by contract is a well‐known software design methodology which enhances the quality of software through assertions expressed at the interface level. The overhead averse nature of High‐Performance Computing (HPC) applications often precludes the use of design by contract due to its potential overhead, especially when handling the large data sizes common in HPC. Our approach is to reduce the overhead of design by contract, by postponing (or offloading) across time and space the enforcement of contracts. We argue that the semantic implications of this approach are not significant, while leading to a large potential overhead reduction. A reduced overhead strategy to contract implementation may be necessary for a wider acceptance of this useful software engineering primitive. We apply our approach to contracts developed for software components based on the CCA (Common Component Architecture) model, which targets HPC applications. Copyright © 2011 John Wiley & Sons, Ltd.
N,N′‐Bis(2,2′‐bipyridine‐6‐ylmethyl)‐2,2′‐biphenylenediamines: A Tuneable Ligand Scaffold for Room Temperature Fe2+ SCO Complexes
Authors: Petzold Holm , Heider Silvio
Published: January 2011

Condensation and subsequent reduction of 2,2′‐diaminobiphenyls 5 with 6′‐ and 5′‐substituted 6‐carbaldehyde‐2,2′‐bipyridines 4 yielded N,N′‐bis(2,2′‐bipyridine‐6‐ylmethyl)‐2,2′‐biphenyl‐enediamines 7, which were employed as hexadendate ligands with N6 donor sets in the synthesis of dicationic [Fe2+(7‐κ6N)] complexes 8. Dependent on the substitution pattern the respective complexes are found in the HS state (8b and 8c) or show SCO behaviour. By means of temperature‐dependent susceptibility measurements, usingEvans' method, the thermodynamic parameters ΔH, ΔS and T1/2 for the SCO have been determined. T1/2 as well as ΔH are remarkably susceptible to substitution next to the central C–C bond of the biphenyl bridge.
Flexible framework for the operation of distribution networks: synchronizing and connecting grid areas using multi back‐to‐back converters
Authors: de Graaff R. A. A. , Duarte J. L. , Kling W. L. , Vaessen P. T. M.
Published: January 2011

Due to the unbundling of the electricity sector and simultaneously the growing interest in distributed generation, the uncertainty in operation and planning has increased for distribution network operators. To avoid uneconomic investments, flexible solutions are needed. For this, the concept of intelligent nodes is proposed, which is an application of multiple converters with back‐to‐back connections. This contribution addresses the control aspects for one of its specific operation conditions: the transition from supplying a radial feeder with loads and/or generation into controlling the power flow in a meshed network without loss of supply. The theoretical framework is described, followed by the measurement results of a laboratory‐scale demonstration. Copyright © 2011 John Wiley & Sons, Ltd.
Altered motor network activation and functional connectivity in adult tourette's syndrome
Authors: Werner Cornelius J. , Stöcker Tony , Kellermann Thilo , Bath Jessica , Beldoch Margarete , Schneider Frank , Wegener Hans Peter , Shah Jon N. , Neuner Irene
Published: January 2011

Tourette's syndrome (TS) is a developmental neuropsychiatric disorder characterized by motor and vocal tics as well as psychiatric comorbidities. Disturbances of the fronto‐striatal‐thalamic pathways responsible for motor control and impulse inhibition have been previously described in other studies. Although differences in motor performance are well recognized, imaging data elucidating the neuronal correlates are scarce. Here, we examined 19 adult TS patients (13 men, aged 22–52 years, mean = 34.3 years) and 18 age‐ and sex‐matched controls (13 men, aged 24–57 years, mean = 37.6 years) in a functional magnetic resonance imaging study at 1.5 T. We corrected for possible confounds introduced by tics, motion, and brain‐structural differences as well as age, sex, comorbidities, and medication. Patients and controls were asked to perform a sequential finger‐tapping task using their right, left, and both hands, respectively. Task performance was monitored by simultaneous MR‐compatible video recording. Although behavioral data obtained during scanning did not show significant differences across groups, we observed differential neuronal activation patterns depending on both handedness (dominant vs. nondominant) and tapping frequency in frontal, parietal, and subcortical areas. When controlling for open motor performance, a failure of deactivation in easier task conditions was found in the subgenual cingulate cortex in the TS patients. In addition, performance‐related functional connectivity of lower‐ and higher‐order motor networks differed between patients and controls. In summary, although open performance was comparable, patients showed different neuronal networks and connectivity patterns when performing increasingly demanding tasks, further illustrating the impact of the disease on the motor system. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Bismuth(III) Chloride‐Catalyzed Highly Efficient Transesterification of β‐Keto Esters
Authors: Sabitha Gowravaram , Srinivas Rangavajjula , Gopal Peddabuddi , Bhikshapathi M. , Singh Yadav Jhillu
Published: January 2011

Bismuth(III) chloride was found to be an efficient catalyst for the transesterification of a variety of β‐keto esters with a wide range of alcohols to afford transesterified products in good to high yields in short reaction times (see Table).
Reaction of 3‐Hydroxyquinoline‐2,4‐diones with Isocyanates and Thermally Induced Transformation of the Reaction Products
Authors: Mrkvička Vladimír , Lyčka Antonín , Vícha Robert , Klásek Antonín
Published: January 2011

3‐Hydroxyquinoline‐2,4‐diones 1 react with isocyanates to give novel 1,2,3,4‐tetrahydro‐2,4‐dioxoquinolin‐3‐yl (alkyl/aryl)carbamates 2 and/or 1,9b‐dihydro‐9b‐hydroxyoxazolo[5,4‐c]quinoline‐2,4(3aH,5H)‐diones 3. Both of these compounds are converted, by boiling in cyclohexylbenzene solution in the presence of Ph3P or 4‐(dimethylamino)pyridine, to give 3‐(acyloxy)‐1,3‐dihydro‐2H‐indol‐2‐ones 8. All compounds were characterized by IR, and 1H‐ and 13C‐NMR spectroscopy, as well as by EI mass spectrometry.
First Synthesis of aC‐Homosteroid from Pregn‐4‐ene‐3,11,20‐trione
Authors: Zhang Zonglei , Wang Lizhong , Bian Xiaoqin , Sun Qian , Xu Hangxian , Wang Cunde
Published: January 2011

(3α,5α)‐3‐Hydroxy‐C‐homopregnane‐11,20‐dione (3) was prepared in eleven steps from the commercially available pregn‐4‐ene‐3,11,20‐trione (4)viathe 11‐oxo‐13‐formyl‐12,13‐secopregnane intermediate11(Scheme 2). Subjection of this secopregnane to an intramolecular aldol condensation afforded theα,β‐unsaturated key intermediateC‐homopregn‐12‐en‐11‐one12.
Ypsilactosides A and B, Two New C22‐Steroidal Lactone Glycosides from Ypsilandra thibetica
Authors: Lu Yi , Xie Bai‐Bo , Chen Chang‐Xiang , Ni Wei , Hua Yan , Liu Hai‐Yang
Published: January 2011

Two new C22‐steroidal lactone glycosides, ypsilactosides A (1) and B (2), were isolated from the EtOH extract of the whole plant of Ypsilandra thibetica. Their structures were established as (3β,5α,16β,20S)‐3,16‐dihydroxy‐6‐oxopregnane‐20‐carboxylic acid γ‐lactone 3‐(β‐D‐glucopyranoside) (1) and (3β,16β)‐3,16‐dihydroxypregna‐5,20‐diene‐20‐carboxylic acid γ‐lactone 3‐{O‐α‐L‐rhamnopyranosyl‐(1→4)‐O‐α‐L‐rhamnopyranosyl‐(1→4)‐O‐[α‐L‐rhamnopyranosyl‐(1→2)]‐β‐D‐glucopyranoside} (2) on the basis of extensive spectroscopic analyses and chemical degradations.
Two New C20‐Diterpenoid Alkaloids from Aconitum carmichaelii
Authors: Shen Yong , Zuo Ai‐Xue , Jiang Zhi‐Yong , Zhang Xue‐Mei , Wang Hong‐Ling , Chen Ji‐Jun
Published: January 2011

Two new C20‐diterpenoid alkaloids, named aconicarchamines A and B (1 and 2, resp.), were isolated from Aconitum carmichaelii. By UV, IR, MS, and 1D‐ and 2D‐NMR analyses, their structures were elucidated as 14,17‐dihydro‐14,17‐dihydroxyajabicine and 15‐O‐acetyllassiocarpine. Compound 1 is the third C20‐diterpenoid alkaloid with the lycoctine skeleton bearing an exocyclic C‐atom at C(14).
Efficient Synthesis of [1,3]Oxazino[3,2‐f]phenanthridine Derivatives by a Novel 1,4‐Dipolar Cycloaddition Involving a Phenanthridine–Dimethyl Acetylenedicarboxylate Zwitterion and Aromatic Aldehydes
Authors: Li Ming , Pan Lei , Wen Li‐Rong
Published: January 2011

An efficient synthesis of [1,3]oxazino[3,2‐f]phenanthridine derivatives via a three‐component reaction of phenanthridine, dimethyl acetylenedicarboxylate (DMAD), and aromatic aldehydes is described. This novel method is complementary to the classical Huisgen 1,4‐dipolar cycloaddition in that it is well‐suited to the preparation of [1,3]oxazino[3,2‐f]phenanthridines.
Amaryllidaceae Alkaloids from Lycoris radiata
Authors: Feng Tao , Wang Yuan‐Yuan , Su Jia , Li Yan , Cai Xiang‐Hai , Luo Xiao‐Dong
Published: January 2011

A phytochemical investigation on bulbs of Lycoris radiata resulted in the isolation of three new Amaryllidaceae alkaloids, named 5,6‐dehydrodihydrolycorine (1), 6β‐acetoxycrinamine (2), and (+)‐8‐O‐acetylhomolycorine α‐N‐oxide (3), together with eleven known alkaloids, 4–14. The structures of the new alkaloids were established by means of spectroscopic methods, and the known compounds were identified by comparison of their data with those in the literature. Compound 2 showed cytotoxicity against HL‐60, A‐549, and MCF‐7 cells, with IC50 values of 8.1, 24.3, and 15.0 μM, respectively.
Stereocontrolled Synthesis of Unnatural Tetrapeptides Containing L‐Valine Units. Part 3
Authors: Balducci Daniele , Porzi Gianni
Published: January 2011

The stereoselective synthesis of the new nonproteinogenic branched tetrapeptides 9a–9d and 15a,b, containing two L‐valine units and unnatural α‐amino acids, was accomplished starting from the chiral synthon 1a, a monolactim ether easily obtained from L‐valine.
Two‐Step Synthesis of 1,3‐Disubstituted 3,4‐Dihydro‐4‐thioxoquinazolin‐2(1H)‐ones from 1‐Bromo‐2‐fluorobenzenes
Authors: Kobayashi Kazuhiro , Komatsu Toshihide , Yokoi Yuki , Konishi Hisatoshi
Published: January 2011

An efficient synthesis of 3‐alkyl‐3,4‐dihydro‐4‐thioxobenzoquinazolin‐2(1H)‐ones 3 has been accomplished in two steps and in satisfactory yields from 1‐bromo‐2‐fluorobenzenes 1. Thus, the reaction of 1‐fluoro‐2‐lithiobenzenes, generated by the Br/Li exchange between 1 and BuLi, with alkyl isothiocyanates, gives N‐alkyl‐2‐fluorobenzothioamides 2, which, in turn, react with a series of isocyanates in the presence of NaH to give the desired products 3.
Reactions with 4‐Hydroxy‐2‐methylbutananilides: Unexpected Formation of a Cyclopropanecarboxamide
Authors: Mekhael Maged K. G. , Linden Anthony , Heimgartner Heinz
Published: January 2011

The successive treatment of the N,N‐disubstituted 4‐hydroxy‐2‐methylbutanamide 2a with lithium diisopropylamide (LDA) and diphenyl phosphorochloridate (DPPCl) led to the 1‐methylcyclopropanecarboxamide 10 in good yield. This base‐catalyzed cyclization offers a new approach to cyclopropanecarboxamides. Under similar conditions, the N‐monosubstituted 4‐hydroxy‐2‐methylbutanamide 2b gave the 3‐methylpyrrolidin‐2‐one 11. The structure of the cyclopropanecarboxamide 10 was established by X‐ray crystallography.
Flavone 8‐C‐Glycosides from Haberlea rhodopensisFriv. (Gesneriaceae)
Authors: Ebrahimi Samad N. , Gafner Frank , Dell'Acqua Giorgio , Schweikert Kuno , Hamburger Matthias
Published: January 2011

Phytochemical profiling of a MeOH extract from Haberlea rhodopensis by a combination of liquid/liquid extraction, and preparative and semi‐preparative HPLC afforded three new flavone C‐glycosides, hispidulin‐8‐C‐(2″‐O‐syringoyl)‐β‐glucopyranoside (3), hispidulin 8‐C‐(6‐O‐acetyl‐β‐glucopyranoside) (4), and hispidulin 8‐C‐(6‐O‐acetyl‐2‐O‐syringoyl‐β‐glucopyranoside) (5), along with two known phenolic glycosides, myconoside (1) and paucifloside (2). The structures were established by extensive spectroscopic analyses including 1D‐ and 2D‐NMR (COSY, HSQC, and HMBC), and HR‐ESI‐TOF‐MS, and by comparison with published data.
In situ deflection of tendon cell‐cilia in response to tensile loading: an in vitro study
Authors: Lavagnino Michael , Arnoczky Steven P. , Gardner Keri
Published: January 2011

To determine if a correlation exists between tensile loading and the deflection of tendon cell‐cilia in situ, rat‐tail tendon fascicles were stained for tubulin and mounted in a loading device attached to the stage of a confocal microscope. Individual tendon cells (n = 13) were identified and sequential images taken at 0%, 2%, 4%, 6%, and 8% grip to grip strain. The change in ciliary deflection angle was then measured at each strain level. To determine the ability of cilia to return to their original orientation, additional fascicles were loaded to 6% strain and then unloaded to 0% and tendon cell‐ciliary (n = 10) deflection angle measured. There was a weak (r2 = 0.40) but significant (p < 0.0001) correlation between the change in deflection angle and applied strain. Tensile loading produced a change in deflection angle from 0% to 3% (p = 0.039) and from 3% to 6% (p = 0.001) strain. There was no change (p = 1.000) in deflection angle from 6% to 8% strain. Reducing the strain from 6% to 0% resulted in a change (p = 0.048) in angle towards the pre‐load position. However, the angle did not return to the pre‐strain position (p = 0.025). These results demonstrate that tensile loading produces in situ deflection of tendon cell‐cilia and supports the concept that cilia are involved in the mechanotransduction response of tendon cells. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:925–930
Long‐term changes of aggregate‐associated and labile soil organic carbon and nitrogen after conversion from forest to grassland and cropland in northern Turkey
Authors: Kocyigit R. , Demirci S.
Published: January 2011

Soil management systems can have great effect on soil chemical, physical and biological properties. Conversion of forest to grassland and cropland can alter C and N dynamics. The objective of this study was to evaluate the changes in aggregate‐associated and labile soil organic C and N fractions after conversion of a natural forest to grassland and cropland in northern Turkey. This experiment was conducted on plots subject to three different adjacent land uses (forest, grassland and cropland). Soil samples were taken from 0–5, 5–15 and 15–30 cm depths from each land use. Some soil physical (soil texture, bulk density), chemical (soil pH, soil organic matter, lime content, total organic C and N, inorganic N, free and protected organic C) and biological (microbial biomass C and N, mineralizable C and N) properties were measured. The highest and lowest bulk densities were observed in grassland (1.41 g cm−3) and cropland (1.14 g cm−3), respectively. Microbial biomass C and total organic C in forest were almost twice greater than grassland and four‐times greater than cropland. Cultivation of forest reduced total organic N, mineralizable N and microbial biomass N by half. The great portion of organic C was stored in macroaggregates (>250 µm) in all the three land uses. Free organic C comprised smaller portion of soil organic C in all the three land uses. Thus, this study indicated that long‐term conversion of forest to grassland and cropland significantly decreased microbial biomass C, mineralizable C and physically protected organic C and the decreases were the greatest in cropland. Copyright © 2011 John Wiley & Sons, Ltd.
Polyaspartamide‐graft‐Polymethacrylate Nanoparticles for Doxorubicin Delivery
Authors: Licciardi Mariano , Cavallaro Gennara , Di Stefano Mauro , Fiorica Calogero , Giammona Gaetano
Published: January 2011

A new PHEA‐IB‐PMANa+ copolymer has been synthesized and its pH‐induced self‐assembly has been investigated in an aqueous medium. PHEA‐IB‐PMANa+ formed nanoparticles with diameters from 25 to 50 nm upon protonation of the carboxylic acid moieties dislocated along the grafted polymethacrylate sodium salt side chains. The physico‐chemical characterization of the nanoparticles was performed using light scattering, zeta‐potential measurements, SEM, and AFM. Doxorubicin‐loaded nanoparticles were prepared and drug release profiles were evaluated under conditions mimicking physiological media. A biological characterization was carried out by testing the cytotoxicity on Caco‐2 cells, and cellular uptake on mouse monocyte macrophage (J774 A.1) and Caco‐2 cells.

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High‐Tg Transparent Poly(ether sulfone)s Based on Phosphinated Bisphenols
Authors: Lin Ching Hsuan , Chang Sheng Lung , Wei Tsai Pei
Published: January 2011

The preparation of high‐Tg transparent polymers from poly(ether sulfone)s with bulky phosphinate pendants is described. Poly(ether sulfone)s P1–P3 based on biphenylene phosphinate‐substituted bisphenols were prepared. The thermal properties of P1 and P2 were studied and compared with a bisphenol‐A‐based poly(ether sulfone). P1 and P2 are flexible, foldable, and highly transparent with a cutoff wavelength around 327 and 328 nm, respectively. They display higher glass transition temperature (258 and 274 °C) and lower coefficient of thermal expansion (δ = 48 ppm per °C by TMA) than those of P0 (208 °C and δ = 57 ppm per °C).

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Selective Localization of Nanofillers: Effect on Morphology and Crystallization of PLA/PCL Blends
Authors: Wu Defeng , Lin Dongpo , Zhang Jie , Zhou Weidong , Zhang Ming , Zhang Yisheng , Wang Dongmei , Lin Bilei
Published: January 2011

Adding nanofillers to PLA/PCL blends to change their surface and interface properties can improve their phase morphology. Here the selective localization of CNTs and organoclays as the third component in the blend is studied. It is found that clay is selectively localized in the PLA phase and at the phase interface whereas CNTs are mainly found in the PCL phase and at the phase interface. With a reduced viscosity ratio of the blend matrices, the CNTs change their preferred localization from PCL to PLA. The effects of the different selective localization of clay and CNTs on the morphologies are studied. In addition, the crystallization behavior of ternary systems also shows a strong dependence on the selective localization of nanofillers.

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Structure Formation of Non‐Colloidal Particles in Viscoelastic Fluids Subjected to Simple Shear Flow
Authors: Hwang Wook Ryol , Hulsen Martien A.
Published: January 2011

The alignment and the aggregation of particles in a viscoelastic fluid in simple shear flow are qualitatively analyzed using a two‐dimensional direct numerical simulation. Depending on the shear thinning, solvent viscosity, and Weissenburg number, a typical sequence in structural transitions from random particle configuration to string formation is found with clustering and clustered string formation in between. The solvent viscosity and the Weissenburg number, the ratio of normal stress to shear stress, are found to be the most influential parameters for the onset of string formation. The influence of shear thinning is less clear. More shear thinning seems to promote string formation if the stress ratio is constant. The angular velocity of the particles is reduced by approximately 60% when particles form a string, independent of the parameters used.

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‘All‐supramolecular’ Nanocapsules from Low‐Molecular Weight Ureas Through Interfacial Addition Reaction in Miniemulsion
Authors: Groison Emilie , Adjili Salim , Ferrand Alice , Lortie Frédéric , Portinha Daniel , Sintes‐Zydowicz Nathalie
Published: January 2011

This contribution presents a new strategy for preparing nanocapsules with a shell made of a supramolecular polymer which repeating units are held together by reversible interactions rather than covalent bonds. These nanocapsules were prepared in classical miniemulsion through interfacial addition reaction of a diisocyanate (IPDI) and a monoamine (iBA), forming low‐molecular weight bis‐ureas moieties which are strong self‐complementary interacting molecules through hydrogen‐bonding. The nanocapsules present a diameter around 100 nm, and MALDI‐TOF MS and 1H NMR analyses confirm the expected molecular characteristics for the shell. This strategy opens the scope of a new type of nanomaterials exhibiting stimuli‐responsiveness due to the reversible interaction linking the repeating units.

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Cell Transplantation and Gene Therapy in Parkinson's Disease
Authors: Wakeman Dustin R. , Dodiya Hemraj B. , Kordower Jeffrey H.
Published: January 2011

Parkinson's disease is a progressive neurodegenerative disorder affecting, in part, dopaminergic motor neurons of the ventral midbrain and their terminal projections that course to the striatum. Symptomatic strategies focused on dopamine replacement have proven effective at remediating some motor symptoms during the course of disease but ultimately fail to deliver long‐term disease modification and lose effectiveness due to the emergence of side effects. Several strategies have been experimentally tested as alternatives for Parkinson's disease, including direct cell replacement and gene transfer through viral vectors. Cellular transplantation of dopamine‐secreting cells was hypothesized as a substitute for pharmacotherapy to directly provide dopamine, whereas gene therapy has primarily focused on restoration of dopamine synthesis or neuroprotection and restoration of spared host dopaminergic circuitry through trophic factors as a means to enhance sustained controlled dopamine transmission. This seems now to have been verified in numerous studies in rodents and nonhuman primates, which have shown that grafts of fetal dopamine neurons or gene transfer through viral vector delivery can lead to improvements in biochemical and behavioral indices of dopamine deficiency. However, in clinical studies, the improvements in parkinsonism have been rather modest and variable and have been plagued by graft‐induced dyskinesias. New developments in stem‐cell transplantation and induced patient‐derived cells have opened the doors for the advancement of cell‐based therapeutics. In addition, viral‐vector–derived therapies have been developed preclinically with excellent safety and efficacy profiles, showing promise in clinical trials thus far. Further progress and optimization of these therapies will be necessary to ensure safety and efficacy before widespread clinical use is deemed appropriate.Mt Sinai J Med 78:126–158, 2011.©2011 Mount Sinai School of Medicine
Economics of Children's Environmental Health
Authors: Trasande Leonardo
Published: January 2011

Economic analyses are increasingly appearing in the children's environmental‐health literature. In this review, an illustrative selection of articles that represent cost analyses, cost‐effectiveness analyses, and cost‐benefit analyses is analyzed for the relative merits of each approach. Cost analyses remain the dominant approach due to lack of available data. Cost‐effectiveness and cost‐benefit analyses in this area face challenges presented by estimation of costs of environmental interventions, whose costs are likely to decrease with further technological innovation. Benefits are also more difficult to quantify economically and can only be partially alleviated through willingness‐to‐pay approaches. Nevertheless, economic analyses in children's environmental health are highly informative and important informants to public‐health and policy practice. Further attention and training in their appropriate use are needed. Mt Sinai J Med 78:98–106, 2011. © 2011 Mount Sinai School of Medicine
Contributions of Built Environment to Childhood Obesity
Authors: Rahman Tamanna , Cushing Rachel A. , Jackson Richard J.
Published: January 2011

As childhood obesity has reached epidemic proportions, it is critical to devise interventions that target the root causes of obesity and its risk factors. The two main components of childhood obesity are physical inactivity and improper nutrition, and it is becoming increasingly evident that the built environment can determine the level of exposure to these risk factors. Through a multidisciplinary literature review, we investigated the association between various built environment attributes and childhood obesity. We found that neighborhood features such as walkability/bikeability, mixed land use, accessible destinations, and transit increase resident physical activity; also that access to high‐caloric foods and convenience stores increases risk of overweight and obesity, whereas the presence of neighborhood supermarkets and farmers' markets is associated with lower childhood body mass index and overweight status. It is evident that a child's built environment impacts his access to nutritious foods and physical activity. In order for children, as well as adults, to prevent onset of overweight or obesity, they need safe places to be active and local markets that offer affordable, healthy food options. Interventions that are designed to provide safe, walkable neighborhoods with access to necessary destinations will be effective in combating the epidemic of obesity.Mt Sinai J Med 78:49–57, 2011.©2011 Mount Sinai School of Medicine
Accurate fracture modelling using meshless methods, the visibility criterion and level sets: Formulation and 2D modelling
Authors: Zhuang Xiaoying , Augarde Charles , Bordas Stéphane
Published: January 2011

Fracture modelling using numerical methods is well‐advanced in 2D using techniques such as the extended finite element method (XFEM). The use of meshless methods for these problems lags somewhat behind, but the potential benefits of no meshing (particularly in 3D) prompt continued research into their development. In methods where the crack face is not explicitly modelled (as the edge of an element for instance), two procedures are instead used to associate the displacement jump with the crack surface: the visibility criterion and the diffraction method. The visibility criterion is simple to implement and efficient to compute, especially with the help of level set coordinates. However, spurious discontinuities have been reported around crack tips using the visibility criterion, whereas implementing the diffraction method in 3D is much more complicated than the visibility criterion. In this paper, a tying procedure is proposed to remove the difficulty with the visibility criterion so that crack tip closure can be ensured while the advantages of the visibility criterion can be preserved. The formulation is based on the use of level set coordinates and the element‐free Galerkin method, and is generally applicable for single or multiple crack problems in 2D or 3D. The paper explains the formulation and provides verification of the method against a number of 2D crack problems. Copyright © 2011 John Wiley & Sons, Ltd.
Fast kd‐tree‐based hierarchical radiosity for radiative heat transport problems
Authors: Bindick Sebastian , Stiebler Maik , Krafczyk Manfred
Published: January 2011

In this paper we present a new efficient approach for radiative heat transfer simulations for various applications in engineering, combining existing approaches from different fields of computer science and heat transfer. For these application fields we assume radiative exchange between gray, diffuse surfaces in a radiatively nonparticipating medium. To solve the complex space–time behavior of radiation in 3D domains we use the hierarchical radiosity method. Here, the basic idea is to hierarchically subdivide surfaces forming a quad‐tree structure until a refinement criterion is reached. The fundamental underlying operation of the radiosity method is visibility detection which can be solved efficiently by using a space partitioning approach for the input surfaces. For this reason we choose a kd‐tree which is the best known acceleration structure for visibility detection on irregularly distributed surfaces. These approaches dramatically decrease the complexity of the radiation problem from n3 to O((k2 + n)logk), where k is the number of input surfaces and n is the number of refined surfaces. We validate the approach for several non‐trivial examples and demonstrate that the scheme is second‐order accurate. Copyright © 2011 John Wiley & Sons, Ltd.
Optimal convergence analysis for the extended finite element method
Authors: Nicaise Serge , Renard Yves , Chahine Elie
Published: January 2011

We establish some optimal a priori error estimates on some variants of the eXtended Finite Element Method (Xfem), namely the Xfem with a cut‐off function and the standard Xfem with a fixed enrichment area. Both the Lamé system (homogeneous isotropic elasticity) and the Laplace problem are considered. The convergence of the numerical stress intensity factors is also investigated. Some numerical experiments corroborating the theoretical results are presented. Copyright © 2011 John Wiley & Sons, Ltd.
Semi‐analytic solution for multiple interacting three‐dimensional inhomogeneous inclusions of arbitrary shape in an infinite space
Authors: Zhou Kun , Keer Leon M. , Wang Q. Jane
Published: January 2011

This paper develops a semi‐analytic solution for multiple arbitrarily shaped three‐dimensional inhomogeneous inclusions embedded in an infinite isotropic matrix under external load. All interactions between the inhomogeneous inclusions are taken into account in this solution. The inhomogeneous inclusions are discretized into small cuboidal elements, each of which is treated as a cuboidal inclusion with initial eigenstrain plus unknown equivalent eigenstrain according to the Equivalent Inclusion Method. All the unknown equivalent eigenstrains are determined by solving a set of simultaneous constitutive equations established for each equivalent cuboidal inclusion. The final solution is obtained by summing up the closed‐form solutions for each individual equivalent cuboidal inclusion in an infinite space. The solution evaluation is performed by application of the fast Fourier transform algorithm, which greatly increases the computational efficiency. Finally, the solution is validated by taking Eshelby's analytic solution of an ellipsoidal inhomogeneous inclusion as a benchmark and by the finite element analysis. A few sample results are also given to demonstrate the generality of the solution. The solution may have potentially significant applications in solving a wide range of inhomogeneity‐related problems. Copyright © 2011 John Wiley & Sons, Ltd.