bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Interionic Structure, and Reactivity toward CO and p‐Methylstyrene of Palladacyclic Compounds Bearing α‐Diimine Ligands
Authors: Zuccaccia Cristiano , Bellachioma Gianfranco , Cardaci Giuseppe , Macchioni Alceo , Binotti Barbara , Carfagna Carla
Published: August 2006

Palladacyclic compounds [Pd(C6H4(C6H5CO)CNR)(NN)] [X] (R = Et, iPr, 2,6‐iPr2C6H3; NN = bpy = 2,2′‐bipyridine, or 1,4‐(o,o′‐dialkylaryl)‐1,4‐diazabuta‐1,3‐dienes; [X]− = [BF4]− or [PF6]−) were synthesized from the dimers [{Pd(C6H4(C6H5CO)CNR)(μ‐Cl)}2] and NN ligands. Their interionic structure in CD2Cl2 was determined by means of 19F,1H‐HOESY experiments and compared with that in the solid state derived from X‐ray single‐crystal studies. [Pd(C6H4(C6H5CO)CNR)(NN)] [X] complexes were found to copolymerize CO and p‐methylstyrene affording syndiotactic or isotactic copolymers when bpy or 1,4‐(o,o′‐dimethylaryl)‐1,4‐diazabuta‐1,3‐dienes were used, respectively. The reactions with CO and p‐methylstyrene of the bpy derivatives were investigated. Two intermediates derived from a single and a double insertion of CO into the PdC bonds were isolated and completely characterized in solution.
Chiral (Diphosphonite)platinum Complexes in Asymmetric Hydroformylation
Authors: van Duren Ruben , Cornelissen Leandra L. J. M. , van der Vlugt Jarl Ivar , Huijbers Jeroen P. J. , Mills Allison M. , Spek Anthony L. , Müller Christian , Vogt Dieter
Published: August 2006

The chiral diphosphonite ligand (11bR,11′bR)‐4,4′‐(9,9‐dimethyl‐9H‐xanthene‐4,5‐diyl)bis[dinaphtho[2,1‐d:1′,2′‐f][1,3,2]dioxaphosphepin] ((R,R)‐XantBino; (R)‐1), based on a rigid xanthene backbone, was applied in the Pt/Sn‐catalyzed hydroformylation of styrene (4a), 4‐methylstyrene (4b), vinyl acetate (4c), and allyl acetate (4d), by using a Pt/Sn ratio of 1 : 1. High ee of up to 80% were observed, along with good regioselectivities towards the desired branched aldehydes. For styrene, an interesting inversion in the stereoselection process was observed at elevated temperatures, and a mechanism is proposed considering the temperature dependence of the regioselectivity. The complex [PtCl2{(S,S)‐XantBino}] ((S)‐2) was characterized by X‐ray crystal‐structure analysis, revealing an unusual out‐of‐plane ligand coordination of the metal fragment. The complex [PtCl(SnCl3){(R,R)‐XantBino}] ((R)‐3) was characterized by means of 31P‐NMR spectroscopy.
Copolymerization of 7‐Methylenebicyclo[4.1.0]heptane with Carbon Monoxide Initiated by Optically Active Palladium Complexes
Authors: Takeuchi Daisuke , Yasuda Ayami , Okada Takeshi , Kuwabara Junpei , Osakada Kohtaro , Tomooka Katsuhiko
Published: August 2006

Seven Pd‐complexes with optically active bis[dihydroxazole]‐type ligands promote asymmetric alternating copolymerization of 7‐methylenebicyclo[4.1.0]heptane with CO, which produces an optically active polyketone, [C(CH2)COC6H10]n. The reaction under increased CO pressure (> 5 atm) affords a polymer that contains monomer units with the cis‐cyclohexane‐1,2‐diyl group almost exclusively. The polyketone exhibits positive or negative optical rotation depending on the Pd‐complex. The highest and lowest [α]$\rm{_{{D}}^{25} }$ of the polymer obtained are + 68.9 and − 76.1, respectively. Addition of dibutylcuprate to a solution of the polymer in the presence of Me3SiCl transforms the enone groups of the polymer to silyl enol ether groups, which are ozonized to (silyloxy)oxirane moieties.
Systematic Study of the Asymmetric Methoxycarbonylation of Styrene Catalyzed by Palladium Systems Containing Chiral Ferrocenyl Diphosphine Ligands
Authors: Godard Cyril , Ruiz Aurora , Claver Carmen
Published: August 2006

We present the first systematic study of the Pd‐catalyzed asymmetric methoxycarbonylation of styrene in the presence of chiral ferrocenyl phosphine ligands. The reaction conditions were optimized, and a screening of different catalyst precursors was performed. A number of 1,1′‐bis(phosphino)ferrocenes of theMandyphos, Josiphos, Walphos, andTaniaphostypes were tested in combination with [PdCl2(NCPh)2], in the presence of TsOH as the acid source. These systems afforded high enantioselectivities, although the regioselectivity of the reaction was found to be in favor of the (undesired) linear ester. The catalytic system made with theJosiphosligand1gave rise to an enantiomeric excess (ee) of 86%.
Preparation of Partially Hydrogenated 4,6‐Dimethyldibenzothiophenes
Authors: Kukula Pavel , Gramlich Volker , Prins Roel
Published: August 2006

The synthesis of three key intermediates of the hydrogenation pathway in the hydrodesulfurization of 4,6‐dimethyldibenzothiophene (4,6‐DM‐DBT; 1) is described. The hydrogenated derivatives 1,2,3,4‐tetrahydro‐4,6‐dimethyldibenzothiophene (= 4,6‐dimethyl‐1,2,3,4‐tetrahydrodibenzothiophene; 4,6‐DM‐TH‐DBT; 2), 1,2,3,4,4a,9b‐hexahydro‐4,6‐dimethyldibenzothiophene (= 4,6‐dimethyl‐1,2,3,4,4a,9b‐hexahydrodibenzothiophene; 4,6‐DM‐HH‐DBT; 3), and dodecahydro‐4,6‐dimethyldibenzothiophene (= 4,6‐dimethylperhydrodibenzothiophene; 4,6‐DM‐PH‐DBT; 4) were prepared by direct hydrogenation of 1. The reactions were carried out in continuous and batch reactors by using metal sulfide as well as noble‐metal catalysts. The influence of the reaction conditions on the formation of the products and the distribution of their stereoisomers was studied in detail. The isomers of the main products were isolated and characterized by NMR, GC/MS/MS, and X‐ray crystal‐structure diffractometry.
Asymmetric Hydroformylation of Vinylfurans Catalyzed by {(11bS)‐4‐{[(1R)‐2′‐Phosphino[1,1′‐binaphthalen]‐2‐yl]oxy}dinaphtho[2,1‐d:1′,2′‐f]‐ [1,3,2]dioxaphosphepin}rhodium(I) [RhI{(R,S)‐binaphos}] Derivatives
Authors: Nakano Koji , Tanaka Ryo , Nozaki Kyoko
Published: August 2006

The asymmetric hydroformylation of 2‐ and 3‐vinylfurans (2a and 2b, resp.) was investigated by using [Rh{(R,S)‐binaphos}] complexes as catalysts ((R,S)‐binaphos = (11bS)‐4‐{[1R)‐2′‐phosphino[1,1′‐binaphthalen]‐2‐yl]oxy}dinaphtho[2,1‐d:1′,2′‐f][1,3,2]dioxaphosphepin; 1). Hydroformylation of 2 gave isoaldehydes 3 in high regio‐ and enantioselectivities (Scheme 2 and Table). Reduction of the aldehydes 3 with NaBH4 successfully afforded the corresponding alcohols 5 without loss of enantiomeric purity (Scheme 3).
Cobalt‐Catalyzed Carbonylation of N‐Alkylbenzaldimines to ‘N‐Alkylphthalimidines’ (= 2,3‐Dihydro‐1H‐isoindol‐1‐ones) via Tandem CH Activation and Cyclocarbonylation
Authors: Funk Jeffrey K. , Yennawar Hemant , Sen Ayusman
Published: August 2006

The reaction of N‐alkylbenzaldimines with carbon monoxide (CO) in the presence of cobalt (Co) catalysts resulted in the formation of N‐alkylphthalimidines (Table 1). Their formation is proposed to occur by CH activation of the aryl ring, migratory insertion of the hydride species into the benzaldimine functionality, CO coordination, and insertion into the CoC bond, followed by reductive elimination of the N‐alkylphthalimidine and regeneration of the starting Co species (Scheme 4). Deuterium (2H)‐labeling NMR studies are consistent with this mechanism (Scheme 5).
Chloro(η6‐p‐cymene)(phosphoramidite)ruthenium(II), a 16‐Electron Fragment Stabilized by an η2‐Aryl–Metal Interaction, and Its Use in Asymmetric Cyclopropanation
Authors: Huber Dominik , Kumar P. G. Anil , Pregosin Paul S. , Mikhel Igor S. , Mezzetti Antonio
Published: August 2006

Chloride abstraction from the half‐sandwich complexes [RuCl2(η6‐p‐cymene)(P*‐κP)] (2a: P* = (Sa,R,R)‐1a = (1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐1‐phenylethyl)]phosphoramidite; 2b: P* = (Sa,R,R)‐1b = (1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐(1‐(1‐naphthalen‐1‐yl)ethyl]phosphoramidite) with (Et3O)[PF6] or Tl[PF6] gives the cationic, 18‐electron complexes dichloro(η6‐p‐cymene){(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐phenyl]ethyl}[(1R)‐1‐phenylethyl]phosphoramidite‐κP}ruthenium(II) hexafluorophosphate (3a) and [Ru(S)]‐dichloro(η6‐p‐cymene){(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐naphthalen‐1‐yl]ethyl}[(1R)‐1‐(naphthalen‐1‐yl)ethyl]phosphoramidite‐κP)ruthenium(II) hexafluorophosphate (3b), which feature the η2‐coordination of one aryl substituent of the phosphoramidite ligand, as indicated by 1H‐, 13C‐, and 31P‐NMR spectroscopy and confirmed by an X‐ray study of 3b. Additionally, the dissociation of p‐cymene from 2a and 3a gives dichloro{(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐(1‐(η6‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP)ruthenium(II) (4a) and di‐μ‐chlorobis{(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐1‐(η6‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP}diruthenium(II) bis(hexafluorophosphate) (5a), respectively, in which one phenyl group of the N‐substituents is η6‐coordinated to the Ru‐center. Complexes 3a and 3b catalyze the asymmetric cyclopropanation of α‐methylstyrene with ethyl diazoacetate with up to 86 and 87% ee for the cis‐ and the trans‐isomers, respectively.
Ligand‐Controlled Formation of a Low‐Valent Pincer Rhodium(I)–Dioxygen Adduct Bearing a Very Short OO Bond
Authors: Frech Christian M. , Shimon Linda J. W. , Milstein David
Published: August 2006

Treatment of [{Me2C6H(CH2PtBu2)2}Rh(η1‐N2)] (1a) with molecular oxygen (O2) resulted in almost quantitative formation of the dioxygen adduct [{Me2C6H(CH2PtBu2)2}Rh(η2‐O2)] (2a). An X‐ray diffraction study of 2a revealed the shortest OO bond reported for RhO2 complexes, indicating the formation of a RhIO2 adduct, rather than a cyclic RhIII η2‐peroxo complex. The coordination of the O2 ligand in 2a was shown to be reversible. Treatment of 2a with CO gas yielded almost quantitatively the corresponding carbonyl complex [{Me2C6H(CH2PtBu2)2}Rh(CO)] (3a). Surprisingly, treatment of the structurally very similar pincer complex [{C6H3(CH2PiPr2)2)}Rh(η1‐N2)] (1b) with O2 led to partial decomposition, with no dioxygen adduct being observed.
Palladium‐Promoted Carbon Monoxide/Ethylene/Styrene Terpolymerization Reaction: Throwing Light on the Different Reactivity of the Two Alkenes
Authors: Durand Jérôme , Scarel Alessandro , Milani Barbara , Seraglia Roberta , Gladiali Serafino , Carfagna Carla , Binotti Barbara
Published: August 2006

The catalytic behavior of dicationic bis‐chelated PdII complexes, [Pd(NN)2][PF6]2, in the CO/ethylene/styrene terpolymerization reaction is studied in detail. The bidentate N‐donor ligands were chosen among 2,2′‐bipyridine (1), 1,10‐phenanthroline (3), their symmetrically substituted derivatives 2, 4, and 5, and 3‐alkyl‐substituted 1,10‐phenanthrolines 6–10. The effect of several parameters (like temperature, CO/ethylene pressure, styrene content, reaction time) was investigated and related to the productivity of the catalytic system, to the relative content of the two olefins in the polymeric chains, and to the molecular mass of the synthesized polyketones. The presence of 1,4‐benzoquinone was necessary to reach productivities as high as 16 kg of terpolymer (TP) per gram of Pd. 13C‐NMR spectroscopy was useful to characterize the distribution of the two repetitive units along the polymer chain. Terpolymers with prevailingly isolated CO/styrene units in CO/ethylene blocks as well as terpolymers with CO/styrene and CO/ethylene blocks were obtained by varying the reaction conditions. Detailed MALDI‐TOF‐MS analysis was performed on the CO/ethylene/styrene terpolymers for the first time, and it allowed us to characterize the end groups of the terpolymer chains. The presence of different chain end groups was found to be related to the initial amount of the two alkenes, thus suggesting that different reactions are involved in the initiation and termination steps of the terpolymerization catalytic cycle.
Preparation of C2‐Symmetric Bis[2‐(diphenylphosphino)ferrocen‐1‐yl]‐ methane and Its Use in Rhodium‐ and Ruthenium‐Catalyzed Hydrogenation
Authors: Wang Yaping , Weissensteiner Walter , Mereiter Kurt , Spindler Felix
Published: August 2006

The two diphosphine ligands (Rp,Rp)‐ and (Sp,Sp)‐bis[2‐(diphenylphospino)ferrocenyl]methane, (Rp,Rp)‐ and (Sp,Sp)‐1, resp., were prepared in six steps from (S)‐ and (R)‐ferrocenyl tolyl sulfoxide, respectively (Scheme). In the solid state, both the diborane complex (Rp,Rp)‐1 ⋅ (BH3)2 and the palladium dichloride complex [PdCl2((Rp,Rp)‐1)] were found to adopt C2‐pseudosymmetric structures according to X‐ray analyses (Figs. 2 and 3). In the Rh‐ and Ru‐catalyzed hydrogenation of selected alkenes and ketones in the presence of the new ligands, enantioselectivities of up to 55% ee were obtained.
The Methoxycarbonylation of Vinyl Acetate Catalyzed by Palladium Complexes of [1,2‐Phenylenebis(methylene)]bis[di(tert‐butyl)phosphine]
Authors: Rucklidge Adam J. , Morris George E. , Slawin Alexandra M. Z. , Cole‐Hamilton David J.
Published: August 2006

Palladium complexes of [1,2‐phenylenebis(methylene)]bis[di(tert‐butyl)phosphine] (1) catalyze the methoxycarbonylation of vinyl acetate (= ethenyl acetate) in the presence of methanesulfonic acid (Scheme 1). High selectivities to ester products can be obtained if free phosphine ligand is in excess over the amount of added acid (Table 1). Selectivities to methyl 2‐acetoxypropanoate, a precursor to lactate esters, can be as high as 3.6 : 1 at low temperature and pressure (Table 2). Replacing tBu by iPr groups leads to less‐active catalysts and lower selectivities to the branched product. Replacing the phenylene moiety by a naphthalenediyl moiety also gives lower activity, but with similar selectivity to the phenylene‐based analogues. Linear hydrocarbon‐chain linkers as the backbone instead of the phenylenebis(methylene) linker leads to poor catalysis, except for a propane‐1,3‐diyl linker, which gives good rates but poor branched selectivity (Table 5). The effect of different reaction conditions on the catalysis is discussed. The syntheses of the new xylene‐based diphosphines 2–5 with one to four iPr groups replacing the tBu groups at the P‐atoms of 1 and of the ligands 6 and 7 based on 1,2‐ and 2,3‐dimethylnaphthalene are also described (Schemes 2 and 3).
The role of cyclophosphamide and granulocyte colony‐stimulation factor in achieving high‐level chimerism in allotransplanted limbs
Authors: Muramatsu Keiichi , You‐Xin Song , Hashimoto Takahiro , Matsunaga Tsunemitsu , Taguchi Toshihiko
Published: August 2006

The establishment of a high‐level of chimerism may be the most stable strategy for donor‐specific tolerance. The purpose of this study was to evaluate the efficacy of a new protocol using cyclophosphamide (CYP) and granulocyte colony‐stimulation factor (G‐CSF) to induce high‐level chimerism following rat whole‐limb allotransplantation. Seventy‐three whole‐limb allotransplants from LacZ transgenic rats to LEW rats were performed. CYP was injected at day 2, and G‐CSF was given from day 0 to 3. Nontreated limb allografts were rejected after 4.2 days. In FK506‐treated group for 28 days, the survival time was prolonged to 64 days. In the group treated with CYP/G‐CSF, limb allografts were rejected after 5.4 days and 5 of 15 recipients showed acute lethal graft‐versus‐host disease (GVHD). Polymerase chain reaction (PCR) study showed a high level of chimerism even within 1 week after transplantation. Fourteen of 30 recipients given CYP/G‐CSF/FK506 died within 2 weeks. The limb survival was significantly prolonged, however, with three grafts surviving more than 300 days. Seven recipients (24%) showed chronic GVHD. A high‐level of chimerism was maintained when limb allografts were not rejected by recipients. Limb allografting could function as a vascularized carrier for bone marrow transplantation, provide a continuous source of donor cells and contribute to a high level of chimerism in the recipient. Pretransplant CYP followed by G‐CSF and FK506 treatment significantly prolonged the survival of limb allografts but frequently caused chronic GVHD in the recipients. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:2133–2140, 2006
Regenerative properties of fetal sheep tendon are not adversely affected by transplantation into an adult environment
Authors: Favata Michele , Beredjiklian Pedro K. , Zgonis Miltiadis H. , Beason David P. , Crombleholme Timothy M. , Jawad Abbas F. , Soslowsky Louis J.
Published: August 2006

Tendon injuries account for a significant number of musculoskeletal afflictions each year. While new surgical techniques and rehabilitation protocols have led to improved clinical outcomes, postsurgical scarring remains the most problematic aspect of tendon repair. In contrast to this typical pattern of fibrosis, recent studies have shown that fetal tendon is capable of healing without scar. However, whether this regenerative healing pattern is intrinsic to the fetal tissue itself or the result of its environment is not known. Thus, the objective of this study is to examine the influence of an adult environment on healing in adult and fetal tendons. We hypothesized that injured fetal tendon tissue transplanted into an adult environment would retain a regenerative healing pattern after injury, demonstrating normal histological and mechanical properties. Our results support this hypothesis. Histological analyses revealed considerable alterations in adult tendon transplants after injury while fetal transplants showed no abnormalities. The injured adult tendons also demonstrated elevated levels of TGF‐β1, bFGF, and CD44 at the wound site, whereas the fetal specimens showed little or no such changes in response to injury. The data from our biomechanical studies further corroborate these observations, with significant decreases in the stiffness, modulus, and almost all viscoelastic properties in wounded versus unwounded adult tendons, and fetal specimens showing no differences in mechanical properties between the wounded and unwounded groups. Thus, the results of our investigation demonstrate that the adult environment is not an impediment to scarless repair and that this capability is intrinsic to the fetal tendon itself. Our study also begins to provide insight into the mechanisms controlling this regenerative response. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:2124–2132, 2006
Tephrochronological dating of varved interglacial lake deposits from Piànico‐Sèllere (Southern Alps, Italy) to around 400 ka
Authors: Brauer Achim , Wulf Sabine , Mangili Clara , Moscariello Andrea
Published: August 2006

The sediment record from the Piànico palaeolake in the southern Alps is continuously varved, spans more than 15 500 years, and represents a key archive for interglacial climate variability at seasonal resolution. The stratigraphic position of the Piànico Interglacial has been controversial in the past. The identification of two volcanic ash layers and their microscopic analysis provides distinct marker layers for tephrochronological dating of these interglacial deposits. In addition to micro‐facies analyses reconstructing depositional processes of both tephra layers within the lake environment, their mineralogical and geochemical composition has been determined through major‐element electron probe micro‐analysis on glass shards. Comparison with published tephra data traced the volcanic source regions of the Piànico tephras to the Campanian volcanic complex of Roccamonfina (Italy) and probably the Puy de Sancy volcano in the French Massif Central. Available dating of near‐vent deposits from the Roccamonfina volcano provides a robust tephrochronological anchor point at around 400 ka for the Piànico Interglacial. These deposits correlate with marine oxygen isotope stage (MIS) 11 and thus are younger than Early to Middle Pleistocene previously suggested by K/Ar dating and older than the last interglacial as inferred from macrofloral remains and the geological setting. Copyright © 2006 John Wiley & Sons, Ltd.
Late Quaternary environments, vegetation and agriculture in northern New Zealand
Authors: Horrocks M. , Nichol S. L. , Augustinus P. C. , Barber I. G.
Published: August 2006

A sedimentological and plant microfossil history of the Late Quaternary is preserved in two sediment cores from early Polynesian ditch systems on southern Aupouri Peninsula. The study places human activities into a geomorphological and ecological context and allows comparison of natural and anthropogenic effects on two different geological settings: a floodplain and a relatively closed peat swamp. The data fill part of the current gap in the environmental record from northern New Zealand, namely MIS 3 (57k–26k yr BP). There is evidence for an increase in fire frequency in the region after 40k 14C yr BP, suggesting a shift to drier (and cooler) conditions. Pollen records show that conifer‐hardwood forest dominated by podocarps (especially Dacrydium) prevailed prior to Polynesian arrival and deforestation within the last millennium, with Fuscopsora insignificant throughout. Both cores show sections with gaps in deposition or preservation, possible flood‐stripping of peat during the pre‐Holocene and mechanical disturbance by early Polynesians. The identification of prehistoric starch grains and other microremains of introduced Colocasia esculenta (taro) in both cores supports indirect evidence that the ditch systems of far northern New Zealand were used for the extensive cultivation of this crop. Copyright © 2006 John Wiley & Sons, Ltd.
Chemical composition, antinutritional constituents, precaecal crude protein and amino acid digestibility in three unconventional tropical legumes in broilers
Authors: Iyayi Eustace A , Kluth Holger , Rodehutscord Markus
Published: August 2006

Three tropical crop seeds, namely Enterolobium cyclocarpum, Mucuna pruriens and Centrosema pubescens, were assessed for their contents of chemical constituents, antinutritional factors (ANFs), crude protein (CP) and amino acid (AA) digestibility. Their meals were incorporated into broiler diets in place of maize starch at two levels (150 and 300 g kg−1). Four hundred and twenty 1‐day‐old broilers were randomly assigned to seven experimental diets on a weight basis and used to determine CP and AA digestibility in the diets and seeds, and performance of the birds. The CP contents were 237, 278 and 252 g kg−1 DM in E. cyclocarpum, M. pruriens and C. pubescens, respectively. Compared to the basal diet, the digestibility of CP and AAs in the diets and seeds was significantly (p < 0.05) reduced at higher level of inclusion of E. cyclocarpum and M. pruriens but increased at higher C. pubescens inclusion. Digestibility of arginine, threonine and lysine in the C. pubescens meal diets was similar to that in the basal diet. Digestibility values of CP and AAs were least in E. cyclocarpum. Aspartic acid was the least and glutamic acid the most digested AA in all the seeds. Among the essential AAs, threonine was the least digested AA, while leucine (in E. cyclocarpum and M. pruriens) and lysine (in C. pubescens) had the highest digestibility with values of 65, 73 and 72%, respectively. Feed intake, body weights and weight gain in the birds were significantly (P < 0.05) reduced in the E. cyclocarpum and M. pruriens diets but increased in the C. pubescens diets compared to the basal diet. Results of the study suggest that, based on the CP content and AA profiles in the seeds, they have potential for poultry feeding. The presence of ANFs, especially in E. cyclocarpum and M. pruriens, however, could be a major limitation in their use in poultry feeding. Copyright © 2006 Society of Chemical Industry
Quantum information of a three-level atom in one-dimensional photonic bandgaps
Authors: Abdel-Aty M , Saif F
Published: August 2006

In this paper a novel analytical method is applied to the problem of investigating the fidelity and linear entropy of a three-level system in the presence of a photonic band gap. Using this analytic solution, we conclusively calculate the fidelity and linear entropy, related particularly to the entanglement phenomena. We demonstrate how fluctuations in the fidelity and linear entropy are effected by the presence of the photonic-band-gap. The outcomes are illustrated with numerical simulations applied to GaAs. It is found that the time evolution of the lower bound of the linear entropy systematically captures the corresponding collapse and revival features. Our work also sheds light on quantum information storage and processing with multi-level atoms.
Nucleation, growth and characterization studies of a nonlinear
optical crystal – tris allylthiourea cadmium chloride (ATCC)
Authors: Siddheswaran R , Sankar R , Rathnakumari M , Jayavel R , Murugakoothan P , Sureshkumar P
Published: August 2006

The nonlinear optical crystals of tris allylthiourea
cadmium chloride have been grown by temperature lowering solution
growth technique. Solubility of ATCC has been determined for
various temperatures. Meta stable zone width and induction period
values have been determined in order to optimize the growth
parameters. Nucleation parameters such as Interfacial tension,
critical radius and the free energy of formation of critical
nucleus have been evaluated. The as grown crystals were
characterized by the powder X-ray diffraction, UV-VIS absorption
and transmittance, FT-IR absorption, TGA-DTA, Dielectric and micro
hardness studies.
Laser induced negative conductivity of diamond
Authors: Baturin A S , Belousov Yu M , Gorelkin V N , Krainov V P , Rastunkov V S
Published: August 2006

We consider the negative mobility of electrons in
diamond excited by a picosecond laser pulse at low temperatures,
due to the inelastic electron-phonon collisions. For the first
time the dependence of the deformation potential on the phonon
wave number has been taken into account. This dependence changes
significantly the region of the negative electron mobility as a
function of the phonon temperature.
Investigation of cluster formation in reversed micelles
systems by the method of correlation spectroscopy of scattered
light
Authors: Potapov A V , Alekseev D B , Alekseeva I G , Saletsky A M
Published: August 2006

Influences of temperature, water content ω and
ethylene glycol on the structure of waterless and hydrated
reversed micelles solutions have been studied by the method of
correlation spectroscopy of scattered light. Two points on the
temperature scale, characterizing threshold of the formation of
micellar clusters and threshold of the stability of surfactant
hydrocarbon layer of micelle, were registered and their location
dependencies on ω were established.
Experimental investigation of laser power addition
with composite four-mirror cavity
Authors: Lei M , Gong M , Zhang H , Liu Q , Wang Y
Published: August 2006

Beam combination is an effective geometry which can
improve laser output power with good beam quality. A new and
practical four-mirror cavity configuration is presented to combine
the beams intracavity. This close-ended scheme is good at
withstanding environmental perturbations and is easier to realize
the alignment than the conventional Michelson cavity. The length
of each arm can be rather short which makes the cavity more
compact in practical implement. With this four-mirror cavity, the
output brightness is efficiently improved compared to single F-P
cavity laser by combining two Nd:YAG lasers. A single beam output
exceeding 3.3 W is achieved in this composite cavity, which has
the potential for scaling to much higher output power with high
brightness.
On temperature dependence of the valence band in the
Raman spectrum of liquid water
Authors: Kargovsky A V
Published: August 2006

We propose the model of liquid water as an ideal
mixture of small water associates in dynamical equilibrium state
for description of the temperature dependence of the valence band
shape in the Raman spectrum. The Placzek's theory of vibrational
Raman scattering is used for the spectrum simulation. The
presented model gives valid results, which are in qualitative
agreement with experimental data in the temperature range
-20...80°C. We show that clusters consisting of three
and four water molecules dominate in the given temperature range,
but monomer and dimer concentrations are relatively small at room
temperature. Different polarization types of Raman spectra are
discussed.
Genomic organization and structure of the 5′‐flanking region of the TEX101 gene: Alternative promoter usage and splicing generate transcript variants with distinct 5′‐untranslated region
Authors: Tsukamoto Hiroki , Takizawa Toshihiro , Takamori Kenji , Ogawa Hideoki , Araki Yoshihiko
Published: August 2006

A novel germ cell‐specific antigen, TEX101 (TES101‐reactive protein), was previously identified using a monoclonal antibody directed against mouse testicular cells. TEX101 is specifically located on the plasma membrane of germ cells, and its expression in gonadal organs is sexually dimorphic. To understand the fundamental mechanism directing gene expression, the genomic organization of TEX101 was studied. The gene consists of five translated exons (exons 2–6) and three 5′‐untranslated exons (exon 1a, 1b, and 1c), respectively. TEX101 forms three major transcripts classified by usage of the three 5′‐untranslated exons. One form of TEX101 mRNA is transcribed from exon 1c and spliced to the common acceptor site in exon 2. In the second form of the transcript, exon 1a is spliced to exon 1b and exon 2 in a sequential manner. Splicing from exon 1a to exon 2, arises the third form of transcript. Reverse Transcription (RT)‐polymerase chain reaction (PCR) analysis demonstrated differential expression pattern of the TEX101 transcripts between testis and ovary. Whereas the expression of transcript‐1 is constitutive in male and female gonads, the transcript‐2 and ‐3 are detected only after starting of the spermatogenesis. Luciferase reporter assays using GC‐2spd(ts) cells, a cell line from immortalized mouse testicular cells, showed that the 5′‐flanking sequence of exon 1c has higher promoter activity than exon 1a. Deletion analysis of the chimeric structures indicated that sequences essential to gene expression are present on the 5′‐flanking region between −3186 and +14, where the cluster of five CAAT boxes is located. Taken together, these findings should facilitate an understanding of the regulation of TEX101 expression during gametogenesis. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.
Optimization of self‐reference thermometry using complex field estimation
Authors: Kuroda Kagayaki , Kokuryo Daisuke , Kumamoto Etsuko , Suzuki Kyohei , Matsuoka Yuichiro , Keserci Bilgin
Published: August 2006

Referenceless, or self‐reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self‐reference technique based on complex field estimation using 2D polynomials comprising complex‐valued coefficients was proposed and optimized. Numerical simulations with a Gaussian‐profiled phase distribution demonstrated that the ROI radius had to be 2.3–2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex‐based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase‐based method using the similar‐order optimization strategy. The complex‐based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase‐based method yielded equivalent results with less polynomial orders. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Prevalence and risk factors of overactive bladder syndrome in Fuzhou Chinese women
Authors: Zhang Wenju , Song Yanfeng , He Xiaoyu , Huang Huijuan , Xu Bo , Song Jian
Published: August 2006

Aims

We randomly sampled a community‐based, healthy population to evaluate the prevalence and associated risk factors of overactive bladder (OAB) syndrome by using the International Continence Society (ICS) definition.

Methods

We randomly sampled 6,066 women (3.0% of registered female residents aged 20 years and older in Fuzhou) and mailed Bristol Female Lower Urinary Tract Symptoms questionnaire for women self‐completion. Women (4,684; 77.2%) with evaluable data were included in this study.

Results

The prevalence of OAB was 8.0% (n = 377), OABdry 2.4% (n = 114), and OABwet 5.6% (n = 263), hence 30% had OABdry and 70% OABwet. The prevalence of OAB and OABwet demonstrated an significant increasing with advancing age (P < 0.01). A multiple logistic regression analysis showed menopause, parity >2, constipation, episiotomy, and higher BMI were potential risk factors for OAB, constipation increased the occurrence of OABdry. OABwet was associated with menopause, parity >2, higher fetal birthweight, episiotomy, while cesarean delivery protected against the development of OABwet.

Conclusions

The prevalence of OAB in chinese women is lower than that of most reports in Occidental women, and increases with advancing age. Many potential risk factors increase the occurrence of OAB. Neurourol. Urodynam. 25:717–721, 2006. © 2006 Wiley‐Liss, Inc.
An improved deniable authentication protocol
Authors: Shao Jun , Cao Zhenfu , Lu Rongxing
Published: August 2006

Deniable authentication, which was introduced to realize secure online negotiation, has been an extensive topic of research. Wang et al. proposed an efficient deniable authentication protocol based on ElGamal cryptography. However, in this article, we show that Wang et al.'s protocol (WLT protocol) is vulnerable to the person‐in‐the‐middle (PIM) attack. An adversary who launches a PIM attack can impersonate a valid user to communicate with the verifier, which will eventually lead to the failure of an online negotiation. To mitigate this security breach, we propose an improved deniable authentication protocol based on Wang et al.'s scheme. Further, a detailed security analysis is conducted to verify the proposed scheme. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 48(4), 179–181 2006
The shortest path problem on large‐scale real‐road networks
Authors: Klunder G.A. , Post H.N.
Published: August 2006

The computation of shortest paths between different locations on a road network appears to be a key problem in many applications. Often, a shortest path is required in a very short time. In this article, we try to find an answer to the question of which shortest path algorithm for the one‐to‐one shortest path problem runs fastest on a large real‐road network. An extensive computational study is presented, in which six existing algorithms and a new label correcting algorithm are implemented in several variants and compared on the real‐road network of The Netherlands. In total, 168 versions are implemented, of which 18 versions are variants of the new algorithm and 60 versions are new by the application of bidirectional search. In the first part of the article we present a mathematical framework and a review of existing algorithms. We then describe combinations of existing algorithms with bidirectional search and heuristic‐estimate techniques based on Euclidean distance and landmarks. We also present some useful static reduction techniques. In the final part of the article we present results from computational tests on The Netherlands road network. The new algorithm, which combines concepts from previous work on buckets and label‐correcting techniques, has generally the shortest running times of any of the tested algorithms. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 48(4), 182–194 2006
The Middle Byzantine menu: palaeodietary information from isotopic analysis of humans and fauna from Kastella, Crete
Authors: Bourbou C. , Richards M. P.
Published: August 2006

We report here on the measurements of carbon and nitrogen stable isotopes of bone collagen from the Middle Byzantine site of Kastella, in the city of Heraklion, on the island of Crete, Greece. The data derived from the analysis suggest a diet based primarily on terrestrial, C3 protein, probably from animal sources, with the inclusion of some marine protein. The adult diet at this site is relatively uniform, with no detectable differences between average isotopic values for males and females. We also found that bone collagen δ15N values for a small number of juveniles decreased to adult levels after the age of two years, indicating that weaning occurred at or before this age. Copyright © 2006 John Wiley & Sons, Ltd.
Histological study of compact bone tissue in some mammals: a method for species determination
Authors: Martiniaková M. , Grosskopf B. , Omelka R. , Dammers K. , Vondráková M. , Bauerová M.
Published: August 2006

The purpose of this investigation was to study compact bone tissue microstructure of some mammals in terms of qualitative and quantitative characteristics, with an emphasis on finding an adequate identification key. Altogether, 36 femora of adult pigs, cows, sheep and rabbits were analysed. The qualitative characteristics were examined according to the classification systems of Enlow & Brown (1956) and Ricqlès et al. (1991) in anterior, posterior, medial and lateral views of thin sections. The quantitative characteristics were assessed using the specific software Scion Image (Scion Corporation, US). We measured area, perimeter, and minimum and maximum diameter of the Haversian canals, the secondary osteons and the vascular canals of primary osteons. The observed data were first used to evaluate inter‐ and intra‐species diversity. After that a discriminant function analysis was used for species determination. According to our results the basic structural pattern of the bone tissue was primary vascular plexiform in pigs, cows and sheep. We found dense Haversian bone tissue in all species. In addition, non‐vascular bone tissue was identified in cows and/or primary vascular longitudinal tissue in rabbits. Many resorption lacunae were found between secondary osteons in pigs. The irregular Haversian bone tissue was localised at the periosteal and endosteal borders in sheep. Classification functions for all investigated species gave a correct classification in 73.83% of cases. The most discriminating variables for the compact bone tissue appeared to be perimeter and minimum diameter of primary osteon's vascular canals. The percentage value can be increased by integrating conclusions from the qualitative analysis. Copyright © 2006 John Wiley & Sons, Ltd.
Thyroid involvement with Langerhans cell histiocytosis in a 3‐year‐old male
Authors: Burnett Aaron , Carney David , Mukhopadhyay Sanjay , Scalzetti Ernest M. , Leino Daniel , Souid Abdul‐Kader
Published: August 2006

We report on the thyroid involvement with Langerhans cell histiocytosis (LCH) in a 3‐year‐old male. The patient presented with goiter and primary hypothyroidism. His goiter caused life‐threatening airway obstruction. He developed locally invasive disease 4 years after his response to LCH therapy. LCH should be suspected as a cause of goiter and thyroidectomy is recommended. Pediatr Blood Cancer 2008;50:726–727. © 2006 Wiley‐Liss, Inc.
Prenatal diagnosis of the Cockayne syndrome: survey of 15 years experience
Authors: Kleijer Wim J. , van der Sterre Marianne L. T. , Garritsen Victor H. , Raams Anja , Jaspers Nicolaas G. J.
Published: August 2006

Objective

Evaluation of results in a consecutive series of 29 prenatal diagnoses for the Cockayne syndrome.

Methods

Recovery of DNA‐synthesis in UV‐irradiated cultured fetal cells was measured by scintillation counting of incorporated 3H‐thymidine. Semiquantitative autoradiographic assessment of the recovery of RNA‐synthesis (RecRS) was used as an adjunctive method.

Results

In 26 of the 29 pregnancies at risk, a definite diagnosis was directly made, based on normal (n = 23) or clearly reduced (n = 3) recovery of DNA‐synthesis in UV‐irradiated cultured chorionic villus (CV) cells (n = 23) or amniocytes (n = 3). Adjunctive studies were performed in several pregnancies to corroborate the initial results. On three occasions initial results were unreliable, which required investigation of the recovery of RNA‐synthesis (n = 2) or even additional amniocentesis (n = 1) to achieve a firm diagnosis. Thus, four affected fetuses were diagnosed in 29 pregnancies at risk (13.8%).

Conclusion

Reliable prenatal diagnosis of the Cockayne syndrome can be made by the demonstration of a strongly reduced recovery of DNA‐synthesis in UV‐irradiated cultured chorionic villus cells or amniocytes. Assessment of the recovery of RNA‐synthesis was needed as an adjunctive method in rare cases of poor cell growth and DNA‐synthesis. Copyright © 2006 John Wiley & Sons, Ltd.
Kinetics of the iodine transfer polymerization of vinylidene fluoride
Authors: Boyer Cyrille , Valade David , Lacroix‐Desmazes Patrick , Ameduri Bruno , Boutevin Bernard
Published: August 2006

The kinetics of the iodine transfer polymerization (ITP) of vinylidene fluoride (VDF) was achieved in the presence of three different chain‐transfer agents (CTAs): 1‐iodoperfluorohexane (C6F13I), 1‐iodo‐2H,2H‐perfluorooctane (C6F13CH2CF2I), and 1,1,2,2‐tetrafluoro‐3‐iodopropane (HCF2CF2CH2I). ITPs of VDF carried out in the presence of C6F13I and C6F13CH2CF2I showed the following: (1) a linear increase in DPn versus αVDF, which evidenced the controlled character of ITP, although the polydispersity indices were slightly high (ca 1.5), and (2) theoretical DPn values close to the targeted ones. In contrast, neither of these statements was observed for the ITP of VDF in the presence of HCF2CF2CH2I achieved under the same conditions, even if the synthesized oligomers could be reactivated. Although the CTr values of C6F13I and C6F13CH2CF2I were close (i.e., 7.7 at 75 °C), that of HCF2CF2CH2I was lower (0.3 at 75 °C). The percentages of CF2I and CH2I functionalities were also assessed, and in the course of the reaction, a reduction of CF2I end groups was noted. Then, the mechanism of the ITP of VDF was proposed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5763–5777, 2006
Using Q‐methodology to understand perceived fatigue reported by adolescents with cancer
Authors: Lai Jin‐Shei , Kupst Mary Jo , Cella David , Brown Steven R. , Peterman Amy , Goldman Stewart
Published: August 2006

Although fatigue is an unpleasant symptom commonly experienced by pediatric oncology patients, it also tends to be under‐recognized and under‐treated. A conceptual understanding of how patients perceive fatigue is beneficial for better identification and treatment planning. The purpose of this study was to understand how adolescents with cancer perceive their fatigue and to explore potential factors influencing their perceptions by using Q‐methodology. The sample included 15 patients (ages 12–18 years) from the Chicago metropolitan area who were receiving cancer treatment. All participants completed a 37‐statement Q‐sort task. Data were analyzed by using PQMethod computer software. Results identified three descriptors of perceived fatigues reported by adolescents: energy and related capacity for physical functioning, psychosocial effects, and anemia‐specific concerns. Appropriate referral for patients with the latter two descriptors of fatigue was recommended. Copyright © 2006 John Wiley & Sons, Ltd.
Flare pilot system safety
Authors: Bellovich John , Franklin Jim , Schwartz Bob
Published: August 2006

One of the worst nightmares a plant manager can experience is a complete flare system outage. The flare system is the last line of defense for many refining and petrochemical facilities and, when out of commission, can cause the shutdown of the entire facility. Flare ignition failure may lead to unburned venting of dangerous gases, and may develop into an explosive hazard leading to the loss of property and equipment, or worse, injury to personnel or loss of life. The safety and effectiveness of flaring are dependent upon one or more continuously burning pilots for immediate and sustained ignition of gases exiting a flare burner. Because pilot failure can compromise safety and effectiveness, it should be detected quickly and accurately to allow prompt automatic and/or operator response. Proper disposal of process and waste gases during routine and/or emergency conditions is crucial to help operating facilities protect plant employees and the surrounding community, and to avoid hundreds of thousands of dollars in fines. These reasons alone make the pilot monitoring and ignition system the most important component of any flare system. The advanced flare pilot systems explained in this article offer increased protection from harsh environmental conditions and rapid notice of pilot flame failure. Recently published industry standards for flare pilot design and performance are also discussed. © 2006 American Institute of Chemical Engineers Process Saf Prog, 2007
Regional and local labour market prospects: the importance of ageing in workforce development
Authors: Green Anne , Collis Clive
Published: August 2006

Overall, the labour force in the UK is ageing, although at different rates in different areas. This poses challenges for workforce development, and has implications not only for older workers, but for everyone, everywhere. However, demography is only one element in labour supply. It needs to be considered alongside trends in participation rates and in a broader policy and cultural context, and alongside likely changes in labour demand, in order to gain a picture of regional and local labour market prospects. The thrust of government policy is to raise employment rates amongst older people (aged 50–69) and to promote ‘active ageing’. The decline in employment rates amongst older men evident in the 1980s has been reversed, but participation rates remain low by earlier standards. Shifts in the industrial and occupational structure of employment mean that there is likely to be a growing demand for customer care and service skills, which older people are well‐placed to provide. Yet estimates of ‘replacement demand’ show that some of the most pressing workforce development issues are experienced in declining sectors and occupations, with an older than average age profile. Examples include agriculture and social care in Cornwall, where there is a lack of new recruits to replace those retiring. It is concluded that improved local intelligence on labour market flows and prospects is needed to inform skills and learning priorities. Copyright © 2006 John Wiley & Sons, Ltd.
Population ageing and older workers: employers' perceptions, attitudes and policies
Authors: Loretto Wendy , White Phil
Published: August 2006

Increasing employment of older workers (those aged 50 and over) has been proposed as a strategy to cushion the impact of declining and ageing populations. Focusing on Scotland, this article considers the various measures that have been put forward to counteract population decline, and reviews public policy approaches aimed at increasing economic activity rates among older workers. It is argued that the attitudes and behaviours of employers are a crucial, but neglected, issue within the debates on employability of older workers. After reviewing existing research relating to employers' approaches towards older workers, we present findings from focus groups of employers conducted in four areas of Scotland in 2003. Our findings show that, whilst employers claimed to operate equal opportunities policies, they also showed partiality in favour of and against older workers. There was little evidence of strategic deployment of older workers, either currently, or in relation to forward planning. Instead a range of sectoral, structural and spatial factors influenced the heterogeneous approaches of employers towards older workers. We discuss the future employability of older workers in light of recent migration trends, and conclude by examining the wider relevance of our research for population ageing and decline. Copyright © 2006 John Wiley & Sons, Ltd.