bluuebunny/crossref_metadata_2025 huggingface dataset:
Electroshocking and PIT Tagging of Juvenile Atlantic Salmon: Are There Interactive Effects on Growth and Survival?
Authors: Sigourney Douglas B. , Horton Gregg E. , Dubreuil Todd L. , Varaday Aimee M. , Letcher Benjamin H.
Published: July 2005

Electroshocking and tagging of fish with passive integrated transponder (PIT) tags are two commonly used methods for conducting mark–recapture studies in freshwater environments and are frequently used in combination. We conducted an experiment to test for the effects of electroshocking, tagging, and a combination of electroshocking plus tagging on the growth and survival of Atlantic salmon Salmo salar parr. We used five treatments that included the presence or absence of PIT tags and electroshocking at 300 or 500 V plus a control group. Fish were measured, weighed, and electroshocked on four occasions separated by approximately 2-month intervals. The average (±1 SD) fork length was 62.1 ± 1.9 mm and the average weight was 2.5 ± 0.3 g at the start of the experiment; at the end of the experiment, length averaged 120.5 ± 11.6 mm and weight averaged 20.9 ± 6.1 g. We did not detect any significant effects of electroshocking on growth or survival over the course of the experiment. However, there was evidence that tagging negatively influenced survival over the first interval after initial tagging and that survival was positively correlated with fish size. In addition, tagged fish seemed to suffer a minor depression in growth over the first interval, although differences in size among tagged and untagged fish were nonsignificant throughout the course of the experiment. We suggest that the size at tagging may have a greater effect on survival and growth of small (<80;eqmm) Atlantic salmon parr than the amount of exposure to electroshocking.
Extent of Anadromy in Bull Trout and Implications for Conservation of a Threatened Species
Authors: Brenkman Samuel J. , Corbett Stephen C.
Published: July 2005

The use of radiotelemetry revealed that adult bull trout Salvelinus confluentus moved between freshwater and the Pacific Ocean and between watersheds along coastal Washington. Forty-seven of 82 radio-tagged bull trout implanted in the Hoh River and Kalaloch Creek basins were anadromous, and 23 fish were relocated in five different estuaries up to 47 km south of their tagging locations. Anadromous bull trout typically entered the Hoh River from May to July, ascended as far as 78 km upstream to spawning areas by September, and returned to the ocean to overwinter. This is the first study to verify that anadromy is a primary life history form in coastal bull trout. The presence of anadromy and the irregular periods of freshwater, estuarine, and marine residence observed in this study are consistent with observations reported for other Salvelinus species. These results also demonstrate that anadromous bull trout inhabit a diverse range of estuarine, freshwater, and marine habitats. Their affinity to estuaries and their observed temporal movements suggest that bull trout optimize winter refugia and forage opportunities and are susceptible to incidental mortality in gill-net and recreational fisheries directed at other Pacific salmonids. An understanding of the extent of anadromy, sources of mortality, and diversity of habitats occupied by bull trout is informative in the establishment of appropriate conservation and recovery strategies for this species.
Effect of Measurement Error on Tests of Density Dependence of Catchability for Walleyes in Northern Wisconsin Angling and Spearing Fisheries
Authors: Hansen Michael J. , Beard T. Douglas , Hewett Steven W.
Published: July 2005

We sought to determine how much measurement errors affected tests of density dependence of spearing and angling catchability for walleye Sander vitreus by quantifying relationships between spearing and angling catch rates (catch/h) and walleye population density (number/acre) in northern Wisconsin lakes. The mean measurement error of spearing catch rates was 43.5 times greater than the mean measurement error of adult walleye population densities, whereas the mean measurement error of angling catch rates was only 5.6 times greater than the mean measurement error of adult walleye population densities. The bias-corrected estimate of the relationship between spearing catch rate and adult walleye population density was similar to the ordinary-least-squares regression estimate but differed significantly from the geometric mean (GM) functional regression estimate. In contrast, the bias-corrected estimate of the relationship between angling catch rate and total walleye population density was intermediate between ordinary-least-squares and GM functional regression estimates. Catch rates of walleyes in both spearing and angling fisheries were not linearly related to walleye population density, which indicated that catch rates in both fisheries were hyperstable in relation to walleye population density. For both fisheries, GM functional regression overestimated the degree of hyperdepletion in catch rates and ordinary-least-squares regression overestimated the degree of hyperstability in catch rates. However, ordinary-least-squares regression induced significantly less bias in tests of density dependence than GM functional regression, so it may be suitable for testing the degree of density dependence in fisheries for which fish population density is estimated with mark– recapture methods similar to those used in our study.
Effects of Vitamin‐B Complex Supplementation on Periodontal Wound Healing
Authors: Neiva Rodrigo F. , Al‐Shammari Khalaf , Nociti Francisco H. , Soehren Stephen , Wang Hom‐Lay
Published: July 2005

Background: Reports have demonstrated that nutrient supplements, in particular vitamin‐B complex (Vit‐B), can positively influence wound healing processes. However, limited information is available on the effects of Vit‐B on periodontal wound healing.

Methods: A total of 30 patients (13 males, 17 females) presenting with generalized moderate to severe chronic periodontitis were enrolled in this study. All subjects presented ≥ two teeth in the same sextant with probing depth (PD) ≥5 mm and bleeding upon probing (BOP) in need of access flap surgery (AFS). This study was a randomized, double‐masked, placebo‐controlled clinical trial. Subjects were instructed to take one capsule a day of either Vit‐B (50 mg of the following: thiamine HCl, riboflavin, niacinamide, d‐calcium pantothenate, and pyridoxine HCl; 50 µg each of d‐biotin and cyanocobalamin; and 400 mcg of folate) or placebo for 30 days following AFS. Clinical attachment levels (CAL) and N‐benzoyl‐dl‐arginine‐2‐ naphthylamide (BANA) test scores were measured at baseline and at 90 and 180 days following surgical intervention. Assessments of the healing response were also performed using BOP, gingival index (GI), and plaque index (Pl) at baseline and 7, 14, 30, 90, and 180 days. The mean results of each parameter were averaged within a group. Differences between groups were analyzed by using repeated measures analysis of variance (ANOVA).

Results: Both groups experienced comparable levels of PD reduction following AFS (test: −1.57 ± 0.34; control: −1.50 ± 0.21). Changes in mean CAL were more favorable in Vit‐B supplemented subjects (test: +0.41 ± 0.12; control: −0.52 ± 0.23; P = 0.024). Stratified data demonstrated significantly better results for the test group in both shallow (test: −0.08 ± 0.03; control: −1.11 ± 0.27; P = 0.032) and deep sites (test: +1.69 ± 0.31; control: +0.74 ± 0.23; P = 0.037). No significant differences were observed between groups regarding PI, GI, and BOP. BANA test values were significantly reduced in both groups after surgical treatment and no significant differences were noted between groups.

Conclusion: Vitamin B‐complex supplement in combination with AFS resulted in statistically significant superior CAL gains when compared to placebo. J Periodontol 2005;76:1084‐1091.
A Scanning Electron Microscopy Study of Idiopathic External Tooth Resorption in the Cat
Authors: DeLaurier April , Boyde Alan , Horton Michael A. , Price Joanna S.
Published: July 2005

Background: Multiple idiopathic root resorption (MIRR) is a rare condition in man characterized by cervical resorption leading to significant tooth loss. A similar condition, feline osteoclastic resorptive lesions (FORL), affects up to 70% of domestic cats and thus provides a valuable model for investigating the etiopathogenesis of MIRR. The aim of the present study was to establish changes in the surface microanatomy of the tooth in late stage FORL and to identify whether its location has a surface bias.

Methods: Scanning electron microscopy (SEM) was used to analyze the surface features of enamel and cementum of feline teeth affected with advanced FORL.

Results: Resorption involved the coronal root at the cementoenamel junction (CEJ) in 95% of teeth and focal resorption of intact enamel was observed in 14% of teeth. In 55% of teeth, the main lesion was on the buccal surface and a distinct circumferential resorption “front” was present at the apical margin of resorption. The root surfaces of most affected teeth either lacked extrinsic fibers or cellular lacunae or featured evidence of cementum remodeling. Woven bone‐like tissue was found within lesions, on resorbed dentin, or on the root surface in 27% of teeth.

Conclusions: This study demonstrates that most FORL involve the CEJ, and the presence of focal lesions at this site suggests that this is where resorption is initiated. This implies that local factors in the oral microenvironment play a role in the etiopathogenesis of this condition. The study also shows that FORL are more likely to occur on buccal surfaces and are associated with changes in the microarchitecture of the root surface consistent with destruction of the normal periodontal attachment and stimulation of a reparative response. These findings may be relevant to understanding the etiopathogenesis of multiple idiopathic resorption areas in man. J Periodontol 2005;76:1106‐1112.
Short‐Term Assessment of the Nd:YAG Laser With and Without Sodium Fluoride Varnish in the Treatment of Dentin Hypersensitivity – A Clinical and Scanning Electron Microscopy Study
Authors: Kumar N. Gautham , Mehta D.S.
Published: July 2005

Background: The aim of the present study was to evaluate clinically and under scanning electron microscopy (SEM) the efficacy of Nd:YAG laser irradiation alone and in combination with 5% sodium fluoride varnish in the management of dentin hypersensitivity.

Methods: The study was conducted on 40 patients divided into four groups who had at least one tooth of Grade III mobility with clinically elicitable dentin hypersensitivity. Following the pretreatment assessment of hypersensitivity using the visual analog scale (VAS) and cold air blast test, the selected tooth in all the groups received 1% citric acid treatment for 1 minute. Group 1 patients received no further treatment; group 2, 3, and 4 patients received additional treatment with 5% sodium fluoride varnish, Nd:YAG laser for 2 minutes, and a combination of 5% sodium fluoride varnish and Nd:YAG laser, respectively. Two hours following treatment, hypersensitivity was again assessed, and the teeth were extracted, sectioned, and scanned using scanning electron microscopy (SEM).

Results: The mean VAS score in group 1 showed a 27% increase from baseline, but groups 2, 3, and 4 showed a decrease of 33%, 44%, and 62%, respectively. The mean cold air blast score showed a 22% increase in group 1, but values decreased by 43%, 50%, and 83% in groups 2, 3, and 4, respectively. The number of patent tubules also progressively decreased from group 1 through group 4.

Conclusions: The combination of Nd:YAG laser and 5% sodium fluoride varnish seems to show an impressive efficacy, when compared to either treatment alone, in treating dentin hypersensitivity. The SEM findings seem to relate to the clinical findings in that reduction in number/patency of tubules was associated with improvement in treatment efficacy. J Periodontol 2005;76:1140‐1147.
The Effect of Non‐Steroidal Anti‐Inflammatory Drugs on Bleeding During Periodontal Surgery
Authors: Braganza Annabel , Bissada Nabil , Hatch Craig , Ficara Anthony
Published: July 2005

Background: With the increasing prevalence of individuals taking non‐steroidal anti‐inflammatory drugs (NSAIDs), there is concern as to whether low‐dose NSAIDs cause bleeding problems during periodontal surgery.

Methods: A controlled, single‐blind study was designed to measure the effect of ibuprofen at peak plasma levels on intraoperative bleeding. Fifteen medically healthy subjects (seven males and eight females), each having two sites requiring periodontal surgery of similar complexity, type, and duration, were selected for the study. The subjects were instructed to take ibuprofen prior to one of the surgeries. A standard bleeding time and papillary bleeding index score were recorded at initial consultation, and prior to the first and second surgeries. The volume of aspirated blood was measured during each surgery by subtracting the amount of water used for irrigation from the total volume of fluid (blood + irrigation water) collected at 15‐minute intervals during the surgery.

Results: An analysis of the results showed an increase in intraoperative bleeding when ibuprofen was taken prior to surgery (31.93 ± 15.72 versus 17.80 ± 9.57 ml; P <0.01). Ibuprofen appeared to have its greatest effect on bleeding mid‐surgery. The average bleeding time also increased significantly (P <0.01) when ibuprofen was preadministered (4.17 ± 0.96 versus 3.8 ± 0.92 minutes), although the bleeding remained within the normal range. Papillary bleeding did not show a significant difference between the two surgeries. Surgeries involving osseous resection showed a significant increase in bleeding when ibuprofen was preadministered.

Conclusion: Taken prior to periodontal surgery, ibuprofen increases intraoperative blood loss in patients up to almost two times that of those who did not take ibuprofen. J Periodontol 2005;76:1154‐1160.
Human Histological Research: Is It Necessary? Humane? Ethical?
Authors: Leib Alden M. , Kowalski Charles J.
Published: July 2005

A review of the dental literature in the United States over the past 60 years is replete with studies utilizing human histological evidence for research. The first reference found for the use of human tissue for histological study was published in 1941 in the Journal of Dental Research.1 Much of this literature focuses on the use of block sections, in which teeth scheduled for extraction are removed along with portions of the surrounding soft tissue and bone in order to study the effects of various interventions. The tissue removed in no way facilitates the surgical extraction of the tooth. It is removed to establish the type of healing, repair, or regeneration by histological evidence. There is no compensating benefit to the patient who, in fact, is put at risk—the removal of the extra tissue may compromise the fit of a subsequent prosthetic restoration. J Periodontol 2005;76:1207‐1210.
Mesocrystals: Inorganic Superstructures Made by Highly Parallel Crystallization and Controlled Alignment
Authors: Cölfen Helmut , Antonietti Markus
Published: July 2005

Controlled self‐organization of nanoparticles can lead to new materials. The colloidal crystallization of non‐spherical nanocrystals is a reaction channel in many crystallization reactions. With additives, self‐organization can be stopped at an intermediary step—a mesocrystal—in which the primary units can still be identified. Mesocrystals were observed for various systems as kinetically metastable species or as intermediates in a crystallization reaction leading to single crystals with typical defects and inclusions. The control forces and mechanism of mesocrystal formation are largely unknown, but several mesocrystal properties are known. Mesocrystals are exiting examples of nonclassical crystallization, which does not proceed through ion‐by‐ion attachment, but by a modular nanobuilding‐block route. This path makes crystallization more independent of ion products or molecular solubility, it occurs without pH or osmotic pressure changes, and opens new strategies for crystal morphogenesis.
New thermochromic liquid–crystalline polymer: Synthesis and phase behavior
Authors: Wang Ying , Hu Jian‐She , Zhang Bao‐Yan , Jiang Tong‐Ying
Published: July 2005

A series of new thermochromic side‐chain liquid–crystalline polymers were prepared. The chemical structures of the resulting monomers and polymers were characterized by element analyses, FTIR, 1H‐NMR, and 13C‐NMR. Their mesogenic properties were investigated by differential scanning calorimetry, thermogravimetric analyses, polarizing optical microscopy, and X‐ray diffraction measurements. The influence of the content of dye groups on phase behavior of the polymers was discussed. The polymers P1–P3 showed smectic phase, and P4–P7 revealed cholesteric phase. The polymers containing less than 30 mol % of the dye groups showed good solubility, reversible phase transition, wider mesophase temperature ranges, and higher thermal stability. Experimental results demonstrated that the clearing temperature and mesophase temperature ranges decreased with increasing the concentration of the dye groups. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 329–335, 2005
Preparation of polydimethylsiloxane nanolatices by emulsion polymerization in a water–aminoethanol system
Authors: Zhang Dunming , Jiang Xiqun , Yang Changzheng
Published: July 2005

Stable and translucent polydimethylsiloxane nanolatices in a water–aminoethanol (AE) system were prepared by the emulsion polymerization of octamethylcyclotetrasiloxane (D4) with nonionic polyoxyethylene alcohol ethers and polyoxyethylene aryl ether as surfactants and with KOH as an initiator. The effects of the AE concentration on the emulsion polymerization rate (Rp) of D4 and the physical properties of the resultant nanolatices were investigated. Increasing the AE concentration in the reaction mixture dramatically increased the emulsion Rp value of D4, and the kinetics of the D4 emulsion polymerization in this system were consistent with the Morgan–Kaler theory of microemulsion polymerization. When the AE concentration in the emulsion increased, the transparency value of the resultant emulsion increased, and the size of the droplets in the resultant nanolatices decreased. In addition, the molecular weight of the polysiloxane in the resultant emulsion also increased with the increase in the AE concentration in the reaction mixture. A nanolatex prepared by the emulsion polymerization of 0.98M D4 with 185 g/L AE had a transparency value of 80.9% and a mean diameter of 59.5 nm. The morphology of polysiloxane nanolatices cured with (N,N‐diethylaminomethyl)‐triethoxysilane was observed with transmission electron microscopy, and the size of the globular particles was consistent with that obtained by dynamic light scattering. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 347–352, 2005
Characterization of defatted soy flour and elastomer composites
Authors: Jong L.
Published: July 2005

Defatted soy flour (DSF) is an abundant renewable commodity and is more economically favorable then soy protein isolate or soy protein concentrate. DSF contains soy protein, soy carbohydrate, and soy whey. The aqueous dispersion of DSF was blended with styrene‐butadiene latex to form elastomer composites. The inclusion of soy carbohydrate increased the tensile stress in the small strain region, but reduced the elongation at break. The shear elastic modulus of the composites showed an increase in the small strain region, consistent with its stress‐strain behavior. The inclusion of soy carbohydrate and soy whey also improved the recovery behavior in the nonlinear region. At small strain, the shear elastic modulus of 30% filled composites at 140°C was about 500 times higher than that of the unfilled elastomer, indicating a significant reinforcement effect generated by DSF. Compared with soy protein isolate (SPI), the stress softening effect and recovery behavior under dynamic strain indicate the addition of soy carbohydrate and soy whey may have increased the filler‐rubber interaction. In general, the DSF composites gave better mechanical properties compared with the protein composites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 353–361, 2005
Comparison of thin‐layer and bulk MIPs synthesized by photoinitiated in situ crosslinking polymerization from the same reaction mixtures
Authors: Schneider Frank , Piletsky Sergey , Piletska Elena , Guerreiro Antonio , Ulbricht Mathias
Published: July 2005

The synthesis and comparative characterization of molecularly imprinted polymers (MIPs) in two different formats, as thin layers grafted to the entire surface of polypropylene microfiltration membranes and as conventional particles, are described. Imprinting with atrazine was performed by using itaconic acid and N,N′‐methylene‐bisacrylamide as functional and crosslinker monomers in methanol as the solvent. Polymerization had been initiated by UV irradiation of benzoin ethyl ether and driven to low monomer conversion for the thin‐layer polymers and to high monomer conversion for the bulk materials. The binding performance of MIP composite membranes and of MIP particles packed into cartridges was evaluated in solid‐phase extraction (SPE) experiments of atrazin and simazin from aqueous solutions. The SPE performance depended strongly on pH and buffer concentration. Although an imprinting effect was observed for both formats, the specificity (MIP versus Blank) and the selectivity (atrazin versus simazin) were much higher for the thin‐layer composite membranes than for the bulk polymer particles. In particular, the atrazin/simazin selectivity increased from 32% for the Blank to 78% for the MIP composite membranes. A major reason is the hindered accessibility of the internal pore structure of the particles, whereas the porous filtration membranes are much more compatible with the fast SPE protocol. Furthermore, based on pKa of the functional carboxylic acid groups—from potentiometric titration and polarity of the binding environment—from fluorescent probe analysis, different properties of the imprinted binding sites can be postulated for the two MIP formats. However, the differences between MIP and Blank were much more pronounced for the thin‐layer composite membranes. The hydrophobic surface of the polypropylene membrane appeared to be a major factor affecting the binding performance of thin‐layer MIPs. The new porous composite membranes could be particularly useful as selective SPE materials in environmental, pharmaceutical, and analytical applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 362–372, 2005
Origin of corpses received by the anatomical institute at the University of Jena during the Nazi regime
Authors: Redies Christoph , Viebig Michael , Zimmermann Susanne , Fröber Rosemarie
Published: July 2005

During the Nazi regime (1933–1945), the anatomical institute at the University of Jena received 2,224 corpses, of which approximately 200 originated from executions. The available data clearly suggest that a large portion of these 200 executed persons must be considered victims of Nazi crimes. Approximately an equal number of bodies were delivered from state nursing homes and mental institutions in the state of Thuringia during the same time period. The available data suggest that it is highly likely that many of them were victims of decentralized “euthanasia” programs. The remains of many prisoners of nearby labor camps, mostly from Eastern Europe, are listed in the body register at the institute as well. A group of anatomists and historians has investigated the institute's association with Nazi crimes. Apart from documenting the association, the aim of the investigation is to clarify the whereabouts of the corpses. In particular, it must be ascertained that none of the specimens publicly displayed in the anatomical collection of the Friedrich Schiller University originated in the context of Nazi crimes. Anat Rec (Part B: New Anat) 285B:6–10, 2005. © 2005 Wiley‐Liss, Inc.
Cancer surveillance in ulcerative colitis
Authors: Chambers W M , Warren B F , Jewell D P , McC. Mortensen N J
Published: July 2005

Background

Patients with ulcerative colitis are at a higher risk of developing colorectal cancer than those without the disease. Surveillance programmes are used routinely to detect dysplasia and cancer in patients with ulcerative colitis. However, such programmes are poorly effective. This article discusses possible improvements suggested by recent research.

Methods

Papers relating to cancer associated with ulcerative colitis and surveillance programmes to detect such cancer were identified using Medline searches. Further papers were identified from the reference lists of identified papers.

Results

The probability of cancer for all patients with ulcerative colitis regardless of disease extent was 2 per cent at 10 years, 8 per cent at 20 years and 18 per cent at 30 years; the overall prevalence of colorectal cancer in any patient was 3·7 per cent. Indications for colonoscopic surveillance are extensive disease for 8–10 years, especially in those with active inflammation, a family history of colorectal cancer and primary sclerosing cholangitis. Problems affecting surveillance include the diagnosis of dysplasia, difficulty in differentiating ‘sporadic’ adenomas from a dysplasia-associated lesion or mass, and decision making based on surveillance findings. Molecular genetic and endoscopic advances to alleviate these problems are discussed.

Conclusion

Rates of detection of dysplasia can be improved by chromoendoscopy. Molecular genetics has the potential to identify patients most at risk of cancer and can differentiate between different types of lesion.
Simultaneous analysis of haloperidol, its three metabolites and two other butyrophenone‐type neuroleptics by high performance liquid chromatography with dual ultraviolet detection
Authors: Higashi Yasuhiko , Kitahara Miyuki , Fujii Youichi
Published: July 2005

We investigated simultaneous determination of haloperidol (HAL), its three metabolites [reduced HAL (R‐HAL), 3‐(4‐fluorobenzoyl)propionic acid (FBPA) and 4‐(4‐chlorophenyl)‐4‐hydroxypiperidine (CPHP)] and two related compounds [spiperone (SPI) and droperidol (DRO)] in phosphate‐buffered saline using high‐performance liquid chromatography (HPLC) coupled with dual ultraviolet detection (220 and 250 nm). Retention times of HAL, R‐HAL, FBPA, CPHP, SPI and DRO were 16.8, 11.8, 10.2, 4.1, 12.6 and 8.3 min, respectively. Their lower limits of detection were 7.5, 14, 4.5, 12, 10 and 20 ng/mL in the same order. The coefficients of variation for their intra‐ and inter‐day assays were less than 7.8 and 9.4%, respectively. Of the other centrally acting drugs, only amoxapine interfered with the peak of DRO. Using our procedure, the binding study of tested compounds to synthetic melanin, human serum albumin and α1‐acid glycoprotein was performed by determining the unbound concentration to total concentration ratio. These results indicated that simultaneous assay of HAL, R‐HAL, FBPA, CPHP, SPI and DRO in phosphate‐buffered saline by HPLC equipped with dual ultraviolet detection is simple, sensitive and reproducible. Also, our assay system can be applied to the binding study of these compounds to synthetic melanin, human serum albumin and α1‐acid glycoprotein. Copyright © 2005 John Wiley & Sons, Ltd.
Addition of Nitriles to Alkaline Earth Metal Complexes of 1,2‐Bis[(phenyl)imino]acenaphthenes
Authors: Fedushkin Igor L. , Morozov Alexander G. , Rassadin Oleg V. , Fukin Georgii K.
Published: July 2005

Compounds [Sr(dpp‐bian)(thf)4] (2), [Ba(dpp‐bian)(dme)2.5] (3) and [Mg(dtb‐bian)(thf)2] (4) (dpp‐bian=1,2‐bis[(2,6‐diisopropylphenyl)imino]acenaphthene; dtb‐bian=1,2‐bis[(2,5‐di‐tert‐butylphenyl)imino]acenaphthene) were prepared by reduction of dpp‐bian and dtb‐bian with an excess of metallic Mg, Sr, or Ba in THF or DME. Reactions of [Mg(dpp‐bian)(thf)3], 3, and 4 with diphenylacetonitrile gave keteniminates [Mg(dpp‐bianH)(NCCPh2)(thf)2] (5), [Mg(dtb‐bianH)(NCCPh2)(thf)2] (6), and [Ba(dpp‐bianH)(NCCPh2)(dme)2] (7), respectively. The reaction of 2 with CH3CN in THF gave [{Sr(dpp‐bianH)[N(H)C(CH3)C(H)CN](thf)}2] (8). The compounds 2, 3, 5–8 were characterized by elemental analysis, and IR and NMR spectroscopy. Molecular structures of 2, 3, 7, and 8 were determined by single‐crystal X‐ray diffraction. In contrast to reactions of alkali‐metal reagents, magnesium amides, or yttriumalkyls with α‐H acidic nitriles, which are accompanied by an amine or an alkane elimination, the reactions of [Mg(dpp‐bian)(thf)3] (1), 2, 3, and 4 with such nitriles proceeded with formation of Mg, Sr, and Ba keteniminates and simultaneous protonation of one nitrogen atom of the bian ligand. The NMR spectroscopic data obtained for complex 5 indicated that in solution the amino hydrogen atom underwent the fast (on the NMR timescale) shuttle transfer between both nitrogen atoms of the dpp‐bianH ligand.
Template‐Fabricated Gold Nanowires from Gas‐Phase Transport Reactions
Authors: Köppe Ralf , Schmid Günter , Schneider Sibylle , Schnöckel Hansgeorg
Published: July 2005

Aluminium oxide membranes are partially filled with solid nanowires of gold by chemical vapour transport (1000 to 650 °C) using iodine as the transport agent. The transport is due to the formation of gas‐phase AuI. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Generation and Characterization of Multilayer Systems Consisting of Au55(PPh3)12Cl6 Double Layers and SiO2 Barrier Films
Authors: Reuter Torsten , Neumeier Stefan , Schmid Günter , Koplin Eva , Simon Ulrich
Published: July 2005

Multilayer systems, consisting of Au55(PPh3)12Cl6 double layers and SiO2 barrier films of different thickness, have been generated and characterised. The formation of the double layer between the barrier films was carried out by using spin‐coating techniques. For the generation of the SiO2 films, a plasma‐assisted physical vapour deposition (PAPVD) procedure has been applied, based on an anodic plasma arc process. Samples of up to nine cluster/SiO2 combinations have been produced and have been characterised by AFM and SEM. Impedance measurements showed that there is a characteristic thermally activated frequency dependence of the capacitance of the different systems. The cluster layers interact by dipoles formed in the double layers at low frequencies. It has also been shown that multilayer systems with SiO2 films thicker than 15 nm tend to spontaneously crystallise. Furthermore, wetting problems during the spin‐coating processes have been investigated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Bis(trimethylsilyl)ketene Acetals as C,O‐Dinucleophiles: One‐Pot Formation of Polycyclic γ‐ and δ‐Lactones from Pyridines and Pyrazines
Authors: Rudler Henri , Denise Bernard , Xu Yiming , Parlier Andrée , Vaissermann Jacqueline
Published: July 2005

Bis(trimethylsilyl)ketene acetals react with pyridines, quinoline and isoquinoline in the presence of stoichiometric amounts of methyl chloroformate to give the corresponding dihydropyridine‐, dihydroquinoline‐ and dihydroisoquinoline‐substituted carboxylic acids in satisfactory yields. The regio‐ and diastereoselectivities of the addition reactions, together with the presence or absence of rotamers, have been established. The isolated acids react with peracids to give β‐hydroxy‐δ‐lactones through an intramolecular reaction. Similar lactonizations could also be brought about directly from the azaaromatic compounds in one‐pot reactions with silica gel, iodine or bromine. In these cases δ‐lactones or β‐halo‐δ‐lactones were produced. The behaviour of pyrazines in these transformations is peculiar, since methyl chloroformate on its own induces the formation, through interaction with both nitrogen atoms, of polycyclic γ‐lactones, a reaction formally reminiscent of the double nucleophilic addition of the same ketene acetals to (arene)tricarbonylchromium complexes. Most of the new structures were assigned through X‐ray crystal structure determinations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Extended Cavitands of Nanoscale Dimensions
Authors: Menozzi Edoardo , Onagi Hideki , Rheingold Arnold L. , Rebek Julius
Published: July 2005

New tetrabenzimidazole cavitands with upper rims extended by aromatic groups have been prepared and their X‐ray structures were analyzed. The reversible encapsulation of a series of n‐alkylammonium guests was studied by NMR spectroscopy and mass spectrometry. These guests showed different binding modes and unique interactions with the hydrophobic cavity. The trimethylammonium guests bearing n‐butyl to n‐hexyl substituents stabilize the C4v conformation of the cavitand by additional CH···π interactions with the aromatic upper part. The longest n‐hexylammonium salt adopts a minimal gauche conformation to fit in the cavity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
1,3‐Selenazole
Authors: Below Harald , Pfeiffer Wolf‐Diethard , Geisler Karlheinz , Lalk Michael , Langer Peter
Published: July 2005

The parent 1,3‐selenazole was prepared by cyclization of selenoformamide with α‐bromoacetaldehyde. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Ring Opening of 1‐Azabicyclo[1.1.0]butanes with Hydrazoic Acid – a Facile Access to N‐Unsubstituted Azetidin‐3‐Amines
Authors: Mlostoń Grzegorz , Celeda Małgorzata
Published: July 2005

Sterically congested 1‐azabicyclo[1.1.0]butanes 1 add hydrazoic acid smoothly at 0–5°, giving 3‐azidoazetidines 2 in good to excellent yields. After hydrogenolysis over Pd/C catalyst, compounds 2 were converted into N‐unsubstituted azetidin‐3‐amines 4. Attempted reduction of 2a with Raney‐Ni led to a mixture of the expected azetidin‐3‐amine 4a and the ring‐enlarged 2,5‐dihydro‐1H‐imidazole derivative 5.
New Synthesis of Pyrrolidines via Reaction of γ‐Halocarbanions with Imines
Authors: Mąkosza Mieczysław , Judka Marek
Published: July 2005

γ‐Chlorocarbanions of proper nucleophilicity, generated from 3‐chloropropyl pentachlorophenyl sulfone (=pentachloro[(3‐chloropropyl)sulfonyl]benzene; 1; Ar=C6Cl5), add to electron‐deficient formal imines 3a–l to produce anionic adducts that enter intramolecular substitution leading to substituted pyrrolidines. This new and simple synthesis of pyrrolidines mimics a 1,3‐dipolar cycloaddition, although it proceeds in two distinct steps.
Activation Energies and Reaction Energetics for 1,3‐Dipolar Cycloadditions of Hydrazoic Acid with CC and CN Multiple Bonds from High‐Accuracy and Density Functional Quantum Mechanical Calculations
Authors: Jones Gavin O. , Ess Daniel H. , Houk Kendall N.
Published: July 2005

The reactions of hydrazoic acid (HN3) with ethene, acetylene, formaldimine (H2CNH), and HCN were explored with the high‐accuracy CBS‐QB3 method, as well as with the B3LYP and mPW1K density functionals. CBS‐QB3 predicts that the activation energies for the reactions of hydrazoic acid with ethylene, acetylene, formaldimine, and HCN have remarkably similar activation enthalpies of 19.0, 19.0, 21.6, and 25.2 kcal/mol, respectively. The reactions are calculated to have reaction enthalpies of −21.5 for triazoline formation from ethene, and −63.7 kcal/mol for formation of the aromatic triazole from acetylene. The reaction to form tetrazoline from formaldimine has a reaction enthalpy of −8 kcal/mol (ΔGrxn=+5.6 kcal/mol), and the formation of tetrazole from HCN has a reaction enthalpy of −23.0 kcal/mol. The trends in the energetics of these processes are rationalized by differences in σ‐bond energies in the transition states and adducts, and the energy required to distort hydrazoic acid to its transition‐state geometry. The density functionals predict activation enthalpies that are in relatively good agreement with CBS‐QB3, the results differing from CBS‐QB3 results by ca. 1–2 kcal/mol. Significant errors are revealed for mPW1K in predicting the reaction enthalpies for all reactions.
Application of the ‘Direct Amide Cyclization’ to Peptides Containing an Anthranilic Acid Residue
Authors: Philipova Irena , Linden Anthony , Heimgartner Heinz
Published: July 2005

The 2,2‐disubstituted 2H‐azirin‐3‐amines 7a–7c were used as amino acid synthons to prepare linear peptides derived from anthranilic acid. These linear peptides, which contain α,α‐disubstituted α‐amino acids, were synthesized by using the ‘azirine/oxazolone method’ (Schemes 2–5) and were subjected to the acid‐catalyzed ‘direct amide cyclization’. Unfortunately, all attempts to isolate the ten‐membered cyclotripeptides, by starting with different precursors, failed. Instead of the expected cyclotripeptides, the corresponding 1,3a,7‐triazabenz[e]azulene‐3,6‐diones 12 and 17 (Schemes 2 and 3) were obtained in up to 44% yield. Most likely, these products were formed by a transannular ring contraction of the desired products, followed by dehydration. In the case of the linear precursor 24, the 20‐membered cyclodimer 25 was formed in 50% yield, together with traces of the 1,3a,7‐triazabenz[e]azulene‐3,6‐dione 27 and the completely unexpected quinazolinone 26 (Scheme 5). In the cases of the linear precursors 30 and 34, no ring closure was observed under the conditions of the ‘direct amide cyclization’, which indicates the limitations of this method.
Quantification of the β‐Stabilizing Effect of the Dicarbonyl(η5‐cyclopentadienyl)iron Group
Authors: Dulich Felix , Müller Karl‐Heinz , Ofial Armin R. , Mayr Herbert
Published: July 2005

Kinetic investigations of the reactions of (prop‐2‐enyl)dicarbonyl(cyclopentadienyl)iron complexes 1 with benzhydrylium ions 3, and of dicarbonyl(cyclopentadienyl)[(1,2‐η)propene]iron(II) tetrafluoroborate (9⋅BF4) with π‐nucleophiles have been performed to elucidate the magnitude of the β‐effect of the [(CO)2FeCp] group (Fp group). Introduction of the Fp group into the allylic position of propene and 2‐methylpropene increases the nucleophilicity of the π‐bonds by nine and six orders of magnitude, respectively, with the result that the allyl‐Fp complexes 1a (N=6.78) and 1b (N=8.45) are among the strongest neutral π‐nucleophiles. Replacement of one β‐H‐atom in the isopropyl cation by the Fp group reduces the electrophilicity by more than 20 orders of magnitude, so that 9+ ranks among the weakest cationic C‐electrophiles (E=−11.2).
Fluorinated Diazo Diketones in Rhodium(II)‐Catalyzed Reactions with Sultams: Chemoselective O‐Functionalization of Amide Carbonyl Groups
Authors: Zakharova Valeria M. , Schulze Bärbel , Rodina Ludmila L. , Sieler Joachim , Nikolaev Valerij A.
Published: July 2005

Rhodium(II)‐catalyzed decomposition of fluorinated diazo diketones in the presence of isothiazole‐3(2H)‐one 1,1‐dioxides offers a chemoselective and useful tool for O‐functionalization of their CO groups by interaction with transient fluorine‐containing RhII‐diketocarbenoids. The resulting O‐alkylimidates of isothiazole 1,1‐dioxides, bearing (trifluoromethyl)acetyl groups, easily react with traces of H2O giving rise to stable hydrates of the perfluoroacetyl groups. No O→N isomerization of O‐alkylimidates (similar to the Lander–Chapman rearrangement) was observed under the reaction conditions studied.
Light‐Induced Cycloaddition of 2,3‐Dihydro‐2,2‐dimethyl‐4H‐thiopyran‐4‐one (a 4‐Thiacyclohex‐2‐enone) to Alkenes and Dienes
Authors: Schmidt Kerstin , Kopf Jürgen , Margaretha Paul
Published: July 2005

The reactivity of (thiacyclic)‐2,3‐dihydro‐2,2‐dimethyl‐4H‐thiopyran‐4‐one (1a) in light‐induced cycloadditions to furan (F), acrylonitrile (AN), or 2,3‐dimethylbut‐2‐ene (TME) is compared to that of (carbocyclic) 5,5‐dimethylcyclohex‐2‐enone (1b). Whereas for the more‐flexible thiacycle, the efficiency of [2+2]‐photocycloadduct formation with AN or TME is generally much lower, the diastereoselectivity regarding the ring fusion in the bicyclo[4.2.0]octanes is quite similar for both enones. In contrast, 1a affords exclusively trans‐fused [4+2] cycloadducts with F, while 1b gives predominantly the corresponding cis‐fused products.
Synthesis of the 2‐Alkenyl‐4‐alkylidenebut‐2‐eno‐4‐lactone (=α‐Alkenyl‐γ‐alkylidenebutenolide) Core Structure of the Carotenoid Pyrrhoxanthin via the Regioselective Dihydroxylation of Hepta‐2,4‐diene‐5‐ynoic Acid Esters
Authors: Schmidt‐Leithoff Joachim , Brückner Reinhard
Published: July 2005

A new strategy for the stereoselective synthesis of 4‐alkylidenebut‐2‐eno‐4‐lactones (=γ‐alkylidenebutenolides) with (Z)‐configuration of the exocyclic CC bond at C(4) was developed. It is exemplified by the synthesis of 4‐alkylidenebutenolactone 31 (Scheme 4), which constitutes a substructure of the carotenoids pyrrhoxanthin (1) and peridinin. The formation of the precursor 4‐(1‐hydroxyalkyl)butenolactone 29 was accomplished either by cyclocarbonylation of the prop‐2‐yn‐1‐ol moiety of 27 (→29) or by hydrostannylation of the isopropylidene‐protected alkynoic acid ester 26 (→28) followed by transacetalization/transesterification (→30). The 4‐alkylidenebutenolactone was formed by the anti‐selective Mitsunobu dehydration 29→31.
Tautomerism in 5,8‐Diaza‐7,9‐dicarbaguanine (‘Alloguanine’)
Authors: Wagner Trixie , Han Bo , Koch Guido , Krishnamurthy Ramanarayanan , Eschenmoser Albert
Published: July 2005

An X‐ray structure analysis of the title compound reveals that this purinoid exists in the crystal as two tautomers which interact with each other in the mode of a reverse‐Watson–Crick base pair.
Studies on the oxidation of phenols catalyzed by a copper(II)–Schiff base complex in aqueous solution under mild conditions
Authors: Meng Xiang‐Guang , Zhu Jie , Yan Jie , Xie Jia‐Qing , Kou Xing‐Ming , Kuang Xiao‐Fan , Yu Li‐Feng , Zeng Xian‐Cheng
Published: July 2005

The catalytic oxidation of phenol with hydrogen peroxide using a synthetic copper(II)–Schiff base complex as catalyst has been investigated in phosphate buffer at pH 7 and 25 °C. In order to further investigate the reaction pathway, the catalytic oxidation of hydroquinone, p‐benzoquinone and catechol were also studied under the same conditions. These reactions were found to be pseudo‐first‐order with respect to the concentration of phenolic substances. The rate constants were also calculated. In the presence of catalyst, the kinetics and the HPLC analysis showed that for the first step phenol was oxidized to hydroquinone and catechol, and the catalyst easily promoted the formation of hydroquinone but not catechol, for the second step the dihydroxybenzenes were further oxidized to benzoquinone, and lastly short‐chain acids, including maleic acid and oxalic acid, were formed. The activity of the catalyst hardly decreased during the whole reaction. Addition of imidazole accelerated the oxidation of phenol. The catalytic decomposition of hydrogen peroxide using this catalyst was also investigated. Copyright © 2005 Society of Chemical Industry
Molecular recognition by mass spectrometry
Authors: Di Tullio Alessandra , Reale Samantha , De Angelis Francesco
Published: July 2005

A recent major advance in the field of mass spectrometry in the biomolecular sciences is represented by the study of the supramolecular interactions among two or more partners in the gas phase. A great deal of chemistry and most of biochemistry concerns molecular interactions taking place in solution. The electrospray technique, which allows direct sampling from solution, and soft ionization of the solute without deposition into the analyte of large amounts of energy, guarantees in many cases the survival of noncovalent bondings and, hence, the direct analysis of the supramolecular complexes present in the condensed phase. The proper preparation of the solution to be studied and also the expert and accurate setting and use of the instrumental parameters are the prerequisites for gaining results as to the specific interactions between, for instance, a protein conformationally modified by its specific metal ion, eventually, and a ligand molecule. The analysis of the charge state of the protein itself and of the modifications of the complex integrity by activating collisions are also methods for studying the biomolecule–molecule interactions. Accordingly, this new mass spectrometric approach to the supramolecular chemistry, which could be also defined as ‘supramolecular mass spectrometry’, allows the study of ion–protein, protein–protein, protein–ligand and DNA–drug interactions. Chiral recognition can also be performed in the gas phase, studying by electrospray mass spectrometry the fragmentation of diastereomeric complex ions. Not the least, a deep insight can also be obtained into the formation and nature of inclusion complexes like those formed with crown ethers, cyclodextrins and calixarenes as host molecules. All these topics are treated to a certain extent in this special feature article. Copyright © 2005 John Wiley & Sons, Ltd.
Alpha‐synuclein immunohistochemistry in two cases of co‐occurring idiopathic Parkinson's disease and motor neuron disease
Authors: Klos Kevin J. , Josephs Keith A. , Parisi Joseph E. , Dickson Dennis W.
Published: July 2005

We report on two cases of sporadic idiopathic Parkinson's disease with motor neuron disease co‐occurring in the same individuals. Pathological analysis revealed the presence of Lewy bodies in brainstem nuclei and basal forebrain consistent with Lewy body disease (LBD), as well as motor neuron degeneration and argyrophilic grain disease. We compared our two cases to all previously published pathological cases of combined LBD and motor neuron degeneration. © 2005 Movement Disorder Society
Study on δ‐form complex in syndiotactic polystyrene–organic molecules systems. IV. Formation of complexes with a mixture of solvents and structural changes during the sorption of solvents by syndiotactic polystyrene mesophase membranes
Authors: Mahesh K. P. O. , Tsujita Y. , Yoshimizu H. , Okamoto S. , Mohan D.
Published: July 2005

The syndiotactic polystyrene (sPS) δ form was crystallized from mixtures with different compositions of p‐chlorotoluene–chlorobenzene (p‐CT–CB) and p‐chlorotoluene–1,1,2‐trichloroethane (p‐CT–TCE). The presence of the δ form and TTGG helical conformation was confirmed by Fourier transform infrared and wide‐angle X‐ray diffraction (WAXD) analyses. In sPS/p‐CT–CB and sPS/p‐CT–TCE δ‐form membranes, the relative absorbance (RA) of the p‐chlorotoluene (p‐CT) solvent peak was very high even at very low concentrations of p‐CT in comparison with the RA of higher concentrations of chlorobenzene (CB) or 1,1,2‐trichloroethane (TCE) in the mixtures. However, the RAs of both CB and TCE solvent peaks decreased with decreasing concentrations of CB and TCE in the mixtures. A negligible decrease in the RA of the TTGG helical content was observed with a decreasing concentration of CB or TCE. The WAXD results showed that the 2θ peak positions of the [010] and [$\bar{2}$10] planes of the sPS/p‐CT–CB and sPS/p‐CT–TCE δ‐form membranes appeared in the same position and were almost equal to those of the sPS–p‐CT δ‐form membrane. The mesophases of the sPS–p‐CT [p‐CT (A‐M)] and sPS–TCE [TCE (A‐M)] membranes were used for the sorption studies with different concentrations of various solvents. The sorption amount of aromatic solvents by both p‐CT (A‐M) and TCE (A‐M) mesophase membranes was higher than that of aliphatic solvents, regardless of the size, shape, and nature of the molecular cavity. The 2θ peak of the [010] plane of the sPS membranes slowly approached the original δ‐form value when the sPS mesophase membranes were immersed in various solvents of different concentrations for 48 h. The shifting of the 2θ peak of the [010] plane to the original δ form depended on the nature and concentration of the immersion solvents. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2380–2387, 2005