bluuebunny/crossref_metadata_2025 huggingface dataset:
Expanding the World of Endohedral Fullerenes—The Tm3N@C2n (39≤n≤43) Clusterfullerene Family
Authors: Krause Matthias , Wong Joanna , Dunsch Lothar
Published: December 2004

A new family of endohedral fullerenes, based on an encaged trithulium nitride (Tm3N) cluster, was synthesised, isolated and characterised by HPLC, mass spectrometry, and visible‐NIR and FTIR spectroscopy. Tm3N clusterfullerenes with cages as small as C76 and as large as C88 were prepared and six of them were isolated. Tm3N@C78 is a small clusterfullerene. The two isomers of Tm3N@C80 (I and II) were the most abundant structures in the fullerene soot. Tm3N@C82, Tm3N@C84, and Tm3N@C86 represent a new series of higher clusterfullerenes. All six isolated Tm3N clusterfullerenes were classified as large energy‐gap structures with optical energy gaps between ∼1.2 and ∼1.75 eV. Tm3N@C80 (I) and Tm3N@C80 (II) were assigned to the C80 cages C80:7 (Ih) and C80:6 (D5h). For Tm3N@C78, the analysis pointed to an elliptical carbon cage with C78:1 (D3) or C78:4 (D3h) being the probable structures.
C5H4BR2 Bending in Ferrocenylboranes: A Delocalized Through‐Space Interaction Between Iron and Boron
Authors: Scheibitz Matthias , Bolte Michael , Bats Jan W. , Lerner H.‐Wolfram , Nowik Israel , Herber Rolfe H. , Krapp Andreas , Lein Matthias , Holthausen Max C. , Wagner Matthias
Published: December 2004

A comparison of the molecular structures of mono‐, di‐ and tetraborylated ferrocenes [Fc{B(R1)(R2)}] (R1/R2=Br/Br, Br/Fc, Br/Me, Me/Me, Me/OH, OMe/OMe), 1,1′‐[fc{B(R1)(R2)}2] (R1/R2=Br/Br, Br/Me, OMe/OMe), and 1,1′,3,3′‐[Fe{C5H3(BMe2)2}2] revealed the boryl substituent(s) to be bent out of the Cp ring plane towards the iron center. The corresponding dip angle α* decreases with decreasing Lewis acidity of the boron atom and with increasing degree of borylation at the ferrocene core. This trend is well reproduced by DFT calculations (including [FcBH2], not yet accessible experimentally). A Bader analysis of the electron density topology of [FcBH2] (α*=26.5°; BP86/TZVP) clearly showed that there is no direct iron–boron bonding in this compound. Instead, strongly delocalized orbital interactions have been identified that involve the boron p orbital, Cipso of the adjacent Cp ring, d orbitals at iron, and a through‐space interaction with the second Cp ring. A second important factor is attractive electrostatic interactions, which are enhanced upon ligand bending. Cyclic voltammetric measurements on the series [FcBMe2], 1,1′‐[fc(BMe2)2], and 1,1′,3,3′‐[Fe{C5H3(BMe2)2}2] indicate a substantial anodic shift in the oxidation potential of the central iron atom upon introduction of BMe2 substituents. Addition of 4‐dimethylaminopyridine (DMAP) does not just counterbalance this effect, but leads to a cathodic shift of the FeII/FeIII redox transition far beyond the half‐wave potential of parent ferrocene. In the Mössbauer spectra, a continuous decrease in the quadrupole splitting (QS) is observed upon going from parent ferrocene to [FcBMe2], to 1,1′‐[fc(BMe2)2], and to 1,1′,3,3′‐[Fe{C5H3(BMe2)2}2]. In contrast, no significant differences are found between the QS values of ferrocene, [Fc(BMe2DMAP)], and 1,1′‐[fc(BMe2−DMAP)2].
Roles of JUMONJI in mouse embryonic development
Authors: Jung Jooyoung , Mysliwiec Matthew R. , Lee Youngsook
Published: December 2004

Cardiac development is a complex biological process requiring the integration of cell specification, differentiation, migration, proliferation, and morphogenesis. Although significant progress has been made recently in understanding the molecular basis of cardiac development, mechanisms of transcriptional control of cardiac development remain largely unknown. In search for the developmentally important genes, the jumonji gene (jmj) was identified by gene trap technology and characterized as a critical nuclear factor for mouse embryonic development. Jmj has been shown to play important roles in cardiovascular development, neural tube fusion process, hematopoiesis, and liver development in mouse embryos. The amino acid sequence of the JUMONJI protein (JMJ) reveals that JMJ belongs to the AT‐rich interaction domain transcription factor family and more recently has been described as a member of the JMJ transcription factor family. Here, we review the roles of jmj in multiple organ development with a focus on cardiovascular development in mice. Developmental Dynamics 232:21–32, 2005. © 2004 Wiley‐Liss, Inc.
Genome‐wide identification of female‐enriched genes in zebrafish
Authors: Wen Chaoming , Zhang Zhenhai , Ma Weiping , Xu Min , Wen Zilong , Peng Jinrong
Published: December 2004

Characteristic differences in morphology, physiology, and behavior between a male and female are correlated to the differential selection of sex‐dependent transcriptomes. By using a cDNA array carrying ∼9,000 zebrafish unique genes, we identified a group of genes whose expression are enriched in the female fish. A subset of these genes have been confirmed and further grouped as egg‐enriched genes, as both somatic‐ and egg‐enriched genes or as somatic‐enriched genes by means of RNA gel blot hybridization. Most importantly, a significant proportion of these genes are either functionally unknown or are novel genes. Thus, future studies of this group of genes will help us greatly to understand more about sex‐determination and sex‐related physiology and behavior. In addition, comparison of zebrafish female‐enriched genes with that in Drosophila, we found that only germline genes are shared between vertebrate and invertebrate, suggesting that the process of oogenesis is highly conserved during the evolution. Developmental Dynamics 232:171–179, 2005. © 2004 Wiley‐Liss, Inc.
Peripheral blood fibrocytes contribute to the formation of the avian spleen
Authors: Nagy Nándor , Bíró Éva , Takács Ágnes , Pólos Miklós , Magyar Attila , Oláh Imre
Published: December 2004

Chick–quail chimeric studies were made to determine the origin of the cells of splenic ellipsoid. The ellipsoid is formed by supporting and phagocytic cells, which are embedded in a well‐organized extracellular matrix. Splenic and bursal anlage of 6‐ to 6.5‐day‐old quail embryos were transplanted into the coelomic cavity of 3‐day‐old chick embryos and further incubated for 17 days. CD45+ chicken hemopoietic cells colonized both organs. They formed the cells of the ellipsoid and the periellipsoidal white pulp of the transplanted quail spleen. Chicken‐specific collagen III was produced only in the donor quail spleen, but not in the bursa of Fabricius. The CD45+/collagen I+/collagen III+ cells are probably identical with the mammalian peripheral blood fibrocytes and contribute to the formation of supporting cells, whereas the CD45+/74.2+ ellipsoid‐associated macrophages are of monocytic origin. We provide, for the first time, experimental evidence that peripheral blood fibrocytes exist in the avian species; they are present in the circulation of the chicken embryo and contribute to the organogenesis of the spleen. Developmental Dynamics 232:55–66, 2005. © 2004 Wiley‐Liss, Inc.
Regulation of iro3 expression in the zebrafish spinal cord
Authors: Lewis Katharine E. , Bates Jennifer , Eisen Judith S.
Published: December 2004

Specification of spinal cord neurons is regulated by several different transcription factors. In this study, we analyze expression and regulation of the transcription factor iro3 in zebrafish spinal cord. In addition to its broad expression in the progenitor domain of intermediate spinal cord, iro3 is also expressed in postmitotic ventral neurons, starting at early somitogenesis stages. Initially, this expression is only in two primary motoneurons, CaP and VaP, but by 24 hr postfertilization, iro3 is expressed by all classes of zebrafish spinal motoneurons as well as by a ventral interneuron called VeLD. iro3 expression in the progenitor domain of intermediate spinal cord is regulated independently from its expression in ventral neurons. Hedgehog (Hh) signaling is unnecessary for iro3 expression in intermediate spinal cord, but it is required to repress iro3 expression in the progenitor domain of ventral spinal cord. We also show that the basic helix‐loop‐helix transcription factor Olig2 is required for repression of iro3 expression in the progenitor domain of ventral spinal cord. We discuss our findings in the context of previous studies, suggesting that iro3 represses formation of motoneurons and promotes formation of interneurons. Developmental Dynamics 232:140–148, 2005. © 2004 Wiley‐Liss, Inc.
Turtle–chicken chimera: An experimental approach to understanding evolutionary innovation in the turtle
Authors: Nagashima Hiroshi , Uchida Katsuhisa , Yamamoto Keiko , Kuraku Shigehiro , Usuda Ryo , Kuratani Shigeru
Published: December 2004

Turtles have a body plan unique among vertebrates in that their ribs have shifted topographically to a superficial layer of the body and the trunk muscles are greatly reduced. Identifying the developmental factors that cause this pattern would further our understanding of the evolutionary origin of the turtles. As the first step in addressing this question, we replaced newly developed epithelial somites of the chicken at the thoracic level with those of the Chinese soft‐shelled turtle Pelodiscus sinensis (P. sinensis somites into a chicken host) and observed the developmental patterning of the grafted somites in the chimera. The P. sinensis somites differentiated normally in the chicken embryonic environment into sclerotomes and dermomyotomes, and the myotomes differentiated further into the epaxial and hypaxial muscles with histological morphology similar to that of normal P. sinensis embryos and not to that of the chicken. Epaxial dermis also arose from the graft. Skeletal components, however, did not differentiate from the P. sinensis sclerotome, except for small fragments of cartilage associated with the host centrum and neural arches. We conclude that chicken and P. sinensis share the developmental programs necessary for the early differentiation of somites and that turtle‐specific traits in muscle patterning arise mainly through a cell‐autonomous developmental process in the somites per se. However, the mechanism for turtle‐specific cartilage patterning, including that of the ribs, is not supported by the chicken embryonic environment. Developmental Dynamics 232:149–161, 2005. © 2004 Wiley‐Liss, Inc.
Toll‐like receptor 6‐independent signaling by diacylated lipopeptides
Authors: Buwitt‐Beckmann Ute , Heine Holger , Wiesmüller Karl‐Heinz , Jung Günther , Brock Roland , Akira Shizuo , Ulmer Artur J.
Published: December 2004

Bacterial lipopeptides are strong immune modulators that activate early host responses after infection as well as initiating adjuvant effects on the adaptive immune system. These lipopeptides induce signaling in cells of the immune system through Toll‐like receptor 2 (TLR2)–TLR1 or TLR2–TLR6 heteromers. So far it has been thought that triacylated lipopeptides, such as the synthetic N‐palmitoyl‐S‐[2,3‐bis(palmitoyloxy)‐(2RS)‐propyl]‐(R)‐cysteine (Pam3)‐CSK4, signal through TLR2–TLR1 heteromers, whereas diacylated lipopeptides, like the macrophage‐activating lipopeptide from Mycoplasma fermentans (MALP2) or S‐[2,3‐bis(palmitoyloxy)‐(2RS)‐propyl]‐(R)‐cysteine (Pam2)‐CGNNDESNISFKEK, induce signaling through TLR2–TLR6 heteromers. Using new synthetic lipopeptide derivatives we addressed the contribution of the lipid and, in particular, the peptide moieties with respect to TLR2 heteromer usage. In contrast to the current model of receptor usage, not only triacylated lipopeptides, but also diacylated lipopeptides like Pam2CSK4 and the elongated MALP2 analog Pam2CGNNDESNISFKEK‐SK4 (MALP2‐SK4) induced B lymphocyte proliferation and TNF‐α secretion in macrophages in a TLR6‐independent manner as determined with cells from TLR6‐deficient mice. Our results indicate that both the lipid and the N‐terminal peptides of lipoproteins contribute to the specificity of recognition by TLR2 heteromers and are responsible for the ligand–receptor interaction on host cells.
Cryptopatches and isolated lymphoid follicles: dynamic lymphoid tissues dispensable for the generation of intraepithelial lymphocytes
Authors: Pabst Oliver , Herbrand Heike , Worbs Tim , Friedrichsen Michaela , Yan Sheng , Hoffmann Matthias W. , Körner Heiner , Bernhardt Günter , Pabst Reinhard , Förster Reinhold
Published: December 2004

In comparison to secondary lymphoid organs, gut‐associated lymphoid tissues such as isolated lymphoid follicles (ILF) and cryptopatches (CP) have been less intensively studied. To gain a better insight into processes regulating organization and function of these structures, which are believed to participate in immune responses and extrathymic T cell development, we characterized the lymphoid structures of the murine small intestine in more detail. The size and cellular composition of small intestinal lymphoid aggregations were analyzed in C57BL/6 and BALB/c wild‐type and lymphotoxin (LT)‐deficient mice, by flow cytometry, histology and automated multi‐color immunofluorescence microscopy evaluating large coherent areas of the intestine. These evaluations demonstrate that aggregated lymphoid structures in the small intestine vary in size and cellular composition, with a majority of structures not matching the current definitions of CP or ILF. Accordingly, significant variations depending on species, age and mouse strain were observed. Furthermore, small bowel transplantation revealed a rapid exchange of B but not T cells between host and grafted tissue. Moreover, LT‐deficient animals lack any intestinal lymphoid aggregations yet possess the complete panel of intraepithelial lymphocytes (IEL). In summary, our observations disclose intestinal lymphoid aggregations as dynamic structures with a great deal of inborn plasticity and demonstrate their dispensability for the generation of IEL.
A mass‐conserving Level‐Set method for modelling of multi‐phase flows
Authors: van der Pijl S. P. , Segal A. , Vuik C. , Wesseling P.
Published: December 2004

A mass‐conserving Level‐Set method to model bubbly flows is presented. The method can handle high density‐ratio flows with complex interface topologies, such as flows with simultaneous occurrence of bubbles and droplets. Aspects taken into account are: a sharp front (density changes abruptly), arbitrarily shaped interfaces, surface tension, buoyancy and coalescence of droplets/bubbles. Attention is paid to mass‐conservation and integrity of the interface.

The proposed computational method is a Level‐Set method, where a Volume‐of‐Fluid function is used to conserve mass when the interface is advected. The aim of the method is to combine the advantages of the Level‐Set and Volume‐of‐Fluid methods without the disadvantages. The flow is computed with a pressure correction method with the Marker‐and‐Cell scheme. Interface conditions are satisfied by means of the continuous surface force methodology and the jump in the density field is maintained similar to the ghost fluid method for incompressible flows. Copyright © 2005 John Wiley & Sons, Ltd.
Probability distributions, trading strategies and leverage: an application of Gaussian mixture models
Authors: Lindemann Andreas , Dunis Christian L. , Lisboa Paulo
Published: December 2004

The purpose of this paper is twofold. Firstly, to assess the merit of estimating probability density functions rather than level or classification estimations on a one‐day‐ahead forecasting task of the EUR/USD time series. This is implemented using a Gaussian mixture model neural network, benchmarking the results against standard forecasting models, namely a naïve model, a moving average convergence divergence technical model (MACD), an autoregressive moving average model (ARMA), a logistic regression model (LOGIT) and a multi‐layer perceptron network (MLP). Secondly, to examine the possibilities of improving the trading performance of those models with confirmation filters and leverage.

While the benchmark models perform best without confirmation filters and leverage, the Gaussian mixture model outperforms all of the benchmarks when taking advantage of the possibilities offered by a combination of more sophisticated trading strategies and leverage. This might be due to the ability of the Gaussian mixture model to identify successfully trades with a high Sharpe ratio. Copyright © 2004 John Wiley & Sons, Ltd.
Many faces of risk: Free speech versus public safety
Authors: Jervis Jane L.
Published: December 2004

National controversy erupted when students at a public university invited a man who was on death row for killing a police officer to speak at their graduation ceremony.
Miami Redskins: Deciding about a university nickname
Authors: Risser Paul G.
Published: December 2004

The decision whether to keep or to change a university's nickname is an intense no‐win situation for a new president. To some, the name is racist and insensitive; to others, it reflects great pride and tradition.
High‐throughput assay of rotenone in olive oil using atmospheric pressure chemical ionization tandem mass spectrometry
Authors: di Donna Leonardo , Grassi Giovanni , Mazzotti Fabio , Perri Enzo , Sindona Giovanni
Published: December 2004

A high‐throughput method is presented for the determination of rotenone in contaminated matrices. The procedure involves atmospheric pressure chemical ionization tandem mass spectrometry with a triple‐quadrupole instrument and the use as internal standard of a cycloadduct derivative of rotenone itself. The method was applied to the evaluation of the decay of rotenone in olives and olive oil at various times after exposure to the contaminant. Copyright © 2004 John Wiley & Sons, Ltd.
Ticlopidine quantification in human plasma by high‐performance liquid chromatography coupled to electrospray tandem mass spectrometry. Application to bioequivalence study
Authors: Borges Ney Carter do Carmo , Mendes Gustavo Duarte , Borges André , Oliveira Sandro Evandir de , Barrientos‐Astigarraga Rafael Eliseo , Nucci Gilberto De
Published: December 2004

A rapid, sensitive and specific method to quantify ticlopidine in human plasma using clopidogrel as the internal standard (IS) is described. The analyte and the IS were extracted from acidified plasma by liquid–liquid extraction using diethyl ether–hexane (80 : 20, v/v). The extracts were analyzed by high‐performance liquid chromatography coupled to electrospray tandem mass spectrometry (HPLC/MS/MS). Chromatography was performed isocratically on a Jones Genesis C84 µm analytical column (150 × 4.1 mm i.d.). The method had a chromatographic run time of 3.0 min and a linear calibration curve over the range 1.0–1000 ng ml−1(r2> 0.999427). The limit of quantification was 1.0 ng ml−1. This HPLC/MS/MS procedure was used to assess the bioequivalence of two ticlopidine 250 mg tablet formulations (ticlopidine test formulation from Apotex do Brasil, Brazil, and Ticlid from Sanofi‐Synthelabo, standard reference formulation). A single 250 mg dose of each formulation was administered to healthy volunteers. The study was conducted using an open, randomized, two‐period crossover design with a 2 week washout interval. Since the 90% confidence interval forCmaxand area under the curve ratios were all inside the 80–125% interval proposed by the US Food and Drug Administration, it was concluded that ticlopidine formulation from Apotex do Brasil is bioequivalent to Ticlid formulation with respect to both the rate and the extent of absorption. Copyright © 2004 John Wiley & Sons, Ltd.
Matrix‐assisted laser desorption/ionization mass spectrometry for the characterization of ionic liquids and the analysis of amino acids, peptides and proteins in ionic liquids
Authors: Zabet‐Moghaddam Masoud , Krüger Ralf , Heinzle Elmar , Tholey Andreas
Published: December 2004

Ionic liquids are interesting solvents for a number of applications in chemistry and biotechnology. We characterized five different ionic liquids by laser desorption/ionization (LDI) and by matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry (MS) and studied the analysis of amino acids, peptides and proteins dissolved in these solvents. Signals of both anions and cations of the ionic liquids could be observed both in LDI‐ and in MALDI‐MS. In the latter case, adduct formation between anions and cations of the analytes was observed. Amino acids, peptides and proteins could be analyzed in ionic liquids after addition of matrix substances. Sodium and potassium adducts were not observed in any analysis involving ionic liquids. Low molecular mass compounds and peptides could be analyzed best in the presence of water‐immiscible ionic liquids, whereas proteins gave the best results in water‐miscible ionic liquids. Optimal analysis conditions such as molar matrix‐to‐analyte and ionic liquid‐to‐matrix ratios were determined. Homogeneity of samples in the presence of ionic liquids was reduced compared with classical MALDI preparations. Relative quantitation of amino acids was possible using isotope‐labeled internal standards. MALDI‐MS thus can be used for the analysis of chemical reactions and the screening of enzyme‐catalyzed reactions in ionic liquids and for the analysis of the biocatalysts dissolved in these solvents. Theoretical aspects of ion formation in the presence of ionic liquids both in LDI and MALDI analysis are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of covalently inhibited extracellular lipase from Streptomyces rimosus by matrix‐assisted laser desorption/ionization time‐of‐flight and matrix‐assisted laser desorption/ionization quadrupole ion trap reflectron time‐of‐flight mass spectrometry: localization of the active site serine
Authors: Zehl Martin , Leščić Ivana , Abramić Marija , Rizzi Andreas , Kojić‐Prodić Biserka , Allmaier Günter
Published: December 2004

A chemical modification approach combined with matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry was used to identify the active site serine residue of an extracellular lipase from Streptomyces rimosus R6‐554W. The lipase, purified from a high‐level overexpressing strain, was covalently modified by incubation with 3,4‐dichloroisocoumarin, a general mechanism‐based serine protease inhibitor. MALDI time‐of‐flight (TOF) mass spectrometry was used to probe the nature of the intact inhibitor‐modified lipase and to clarify the mechanism of lipase inhibition by 3,4‐dichloroisocoumarin. The stoichiometry of the inhibition reaction revealed that specifically one molecule of inhibitor was bound to the lipase. The MALDI matrix 2,6‐dihydroxyacetophenone facilitated the formation of highly abundant [M + 2H]2+ ions with good resolution compared to other matrices in a linear TOF instrument. This allowed the detection of two different inhibitor‐modified lipase species. Exact localization of the modified amino acid residue was accomplished by tryptic digestion followed by low‐energy collision‐induced dissociation peptide sequencing of the detected 2‐(carboxychloromethyl)benzoylated peptide by means of a MALDI quadrupole ion trap reflectron TOF instrument. The high sequence coverage obtained by this approach allowed the confirmation of the site specificity of the inhibition reaction and the unambiguous identification of the serine at position 10 as the nucleophilic amino acid residue in the active site of the enzyme. This result is in agreement with the previously obtained data from multiple sequence alignment of S. rimosus lipase with different esterases, which indicated that this enzyme exhibits a characteristic Gly‐Asp‐Ser‐(Leu) motif located close to the N‐terminus and is harboring the catalytically active serine residue. Therefore, this study experimentally proves the classification of the S. rimosus lipase as GDS(L) lipolytic enzyme. Copyright © 2004 John Wiley & Sons, Ltd.
Forecasting Australian drought using Southern Hemisphere modes of sea‐surface temperature variability
Authors: White Warren B. , Gershunov Alexander , Annis Jeffrey L. , McKeon Greg , Syktus Jozef
Published: December 2004

Drought of 3 to 7 years' duration has devastated the flora, fauna, and regional economies in rangeland grazing districts over eastern and central Australia every 15 to 25 years throughout the 20th century, in some cases degrading the land beyond recovery. Recently, these drought and degradation episodes have been associated with a global interdecadal oscillation (IDO) of period 15 to 25 years. This IDO signal brought cooler sea‐surface temperatures (SSTs) to the western extra‐tropical South Pacific Ocean in association with reduced onshore transport of moisture over eastern/central Australia during the summer monsoon. Here, we utilize optimized canonical correlation analysis (CCA) to forecast principal components of summer precipitation (PCP) anomalies over Australia from the persistence of principal components that dominate spring SST anomalies across the Southern Hemisphere. These summer PCP forecasts are cross‐validated with the CCA forecast model for each year independent of that year's variability. Resulting cross‐validated forecasts are best over Queensland, correlating with those observed at >0.40 from 1890 through to 2001, significant at >99% confidence level. More importantly, 6 of 10 drought episodes (but only three of seven degradation episodes) observed in eastern/central Australia during the 20th century are forecast. Copyright © 2004 Royal Meteorological Society
Sudden failure of dual channel pulse generators
Authors: Alesch François
Published: December 2004

An Editor‐Solicited Manufacturer ResposeEditor‐Solicited Manufacturer Respose to this article has been published in Movement Disorders.

We report a series of four sudden hardware failures in dual channel pulse generators implanted for chronic stimulation of the subthalamic nucleus in the treatment of Parkinson's disease. In all cases, a sudden and severe deterioration of the patient's neurological condition occurred with symptoms similar to those present before surgery. In all cases, destructive analysis of the generator revealed a fracture of the wire bonds connecting the battery to the hybrid (electronic) part of the pulse generator. This fracture led to repeated Power On Resets, bringing the parameter settings back to default (factory settings). As a cause, we propose that relative movements between the hybrid and the battery led to low cycle fatigue fractures due to insufficient stiffness of the device. That three of four failures occurred when the implant was in the infracostal region makes it likely that the fractures depend on the mechanical stress applied to the device. The efficacy of the therapy resumed immediately after device replacement. As a corrective measure, the manufacturer has added epoxy between both components, increasing significantly the stiffness of the device. © 2004 Movement Disorder Society
Pallidal deep brain stimulation influences both reflexive and voluntary saccades in Huntington's disease
Authors: Fawcett Adrian P. , Moro Elena , Lang Anthony E. , Lozano Andres M. , Hutchison William D.
Published: December 2004

Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is being evaluated as a potential new therapy for patients with Huntington's disease (HD). In addition to skeletal movement disorders, HD patients have difficulty initiating voluntary saccades and have difficulty in suppressing rapid saccades toward newly appearing stimuli. We measured several saccade parameters in an HD patient who had marked improvement of clinical symptoms with bilateral GPi DBS to determine whether oculomotor performance improved in parallel with clinical scores. Oculomotor performance was assessed using three testing paradigms: pro‐saccades, anti‐saccades, and memory‐guided saccades. The data from the HD patient was also compared to that of two healthy controls. Pallidal DBS decreased pro‐saccade latency, total movement time, and the number of correctly executed trials, as well as increasing saccade gain. Memory–saccade performance was negatively affected with stimulation: saccade gain decreased, latency increased, and the patient's ability to suppress unwanted saccades decreased with stimulation. Our data demonstrate a task‐specific improvement of oculomotor deficits in this HD patient with pallidal DBS, supporting a role of GPi in oculomotor control. © 2004 Movement Disorder Society
Trial of subtherapeutic pergolide in de novo Parkinson's disease
Authors: Grosset Katherine , Grosset Donald , Lees Andrew ,   Parkinson's Disease Research Group of the United Kingdom
Published: December 2004

The effect of pergolide 25 μg twice daily on levodopa initiation was assessed in a randomized, placebo‐controlled, parallel group, double‐blind multicenter trial in 106 untreated early Parkinson's disease patients. The primary endpoint of mean time until levodopa was 520 days (95% confidence interval [CI], 422–618 days) for pergolide versus 434 days (95% CI, 358–609 days) for placebo. However, this increase of 86 days for pergolide was not statistically significant. The wash‐in effect of pergolide was significant at 6 weeks (change in mean Unified Parkinson's Disease Rating Scale [UPDRS] 2 and 3 was −0.1 [95% CI, −1.4 to 1.3] for pergolide vs. 2.2 [95% CI, 1.1–3.3] for placebo). At termination, the change from baseline in mean UPDRS 2 and 3 score was 11.4 (95% CI, 8.8–14) for pergolide and 14.6 (95% CI, 12–17.2) for placebo (P = 0.08). There was no significant change in UPDRS 2 and 3 for the 83 patients achieving the planned 4‐week washout at termination (pergolide 1.2 [95% CI, −0.8 to 3.2] vs. placebo 0.0 [95% CI, −1.6 to 1.6]. Adverse events were infrequent and occurred equally for pergolide and placebo. The study shows no evidence of a neuroprotective effect but indicates a mild symptomatic benefit from pergolide at a dose normally considered subtherapeutic. © 2004 Movement Disorder Society
Melt‐extensional properties and orientation behaviors of polypropylene‐layered silicate nanocomposites
Authors: Koo Chong Min , Kim Jong Hyun , Wang Ki Hyun , Chung In Jae
Published: December 2004

Polypropylene‐layered silicate nanocomposites consisting of three components—pure polypropylene, maleated polypropylene, and organically modified silicate—were prepared by the melt‐intercalation method to investigate melt‐extensional properties such as melt strength, neck‐in test, and orientation behavior. The nanocomposites showed an enhanced tensile modulus, enhanced storage modulus, much enhanced melt tension, and reduced neck‐in during the melt processing as compared with neat polymer. The uniaxial drawing induced the silicate surface to align parallel to the sheet surface. The c and a* axes of the polypropylene crystals were bimodally oriented to the flow direction, and the b axes were oriented to the thickness direction. The bimodal orientation of the polypropylene crystal was enhanced with the concentration of silicates. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 158–167, 2005
Syntheses, Crystal Structures, and Antibacterial Activities of Four Schiff Base Complexes of Copper and Zinc
Authors: You Zhong‐Lu , Zhu Hai‐Liang
Published: December 2004

Four Schiff base complexes, [Cu2(L1)2(μ‐NCS)2] (1), [Cu2(L2)2(μ‐N3)2] (2), Cu[Cu(CH3COO)(L3)]2 (3), and [Zn{Zn(C3H4N2)(L3)}2(NO3)](NO3) (4) (where L1 = 2‐[(pyridin‐2‐ylmethylimino)methyl]phenol, L2 = 1‐[(pyridin‐2‐ylmethylimino)methyl]naphthalen‐2‐ol, and L3 = bis(salicylidene)‐1, 3‐propanediamine), were synthesized and characterized by elemental analyses, infrared spectroscopy, and single crystal X‐ray determinations. Both 1 and 2 are structurally similar di‐nuclear complexes, which are located at crystallographic inversion centers (with the center of the central Cu2N2 ring). In 1, each copper atom has a slightly distorted square pyramidal configuration, coordinated by two nitrogen atoms and one oxygen atom from L1 and another two terminal nitrogen atoms from two bridging thiocyanate anions. The Cu···Cu separation is 3.466(3) Å. The structure of 2 is similar to that of 1, with Cu···Cu separation of 3.368(2) Å. Both 3 and 4 are linear tri‐nuclear complexes. In 3, the central Cu2+ ion is located on an inversion centre and has a distorted octahedral coordination involving four bridging O atoms from two Schiff base ligands (L3) in the equatorial plane and one O atom from each bridging acetate group in the axial positions. The coordination around the terminal Cu2+ ions is irregular‐square pyramidal, with two O and two N atoms of L3 in the basal plane and one O atom from an acetate group in the apical position. The acetate bridges linking the central and terminal Cu2+ ions are mutually trans. The Cu···Cu separation is 3.009(3) Å. In 4, the coordination configuration of the central and the terminal zinc atoms are similar to that of the 3, with Zn···Zn separation of 3.153(4) Å. The three Schiff bases and the corresponding three copper complexes exhibit good antibacterial properties, while the zinc complex 4 has nearly no.
Synthesis and Crystal Structures of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16
Authors: Krivovichev Sergey V. , Kahlenberg Volker
Published: December 2004

Single crystals of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16 have been synthesized by evaporation from an aqueous solution of the ionic components. The structure of α‐Mg2[(UO2)3(SeO4)5](H2O)16 (monoclinic, C2/c, a = 19.544(3), b = 10.4783(11), c = 18.020(3) Å, β = 91.352(12)°, V = 3689.3(9) Å3) has been solved by direct methods and refined to R1 = 0.048 on the basis of 4338 unique observed reflections. The structure of β‐Mg2[(UO2)3(SeO4)5](H2O)16 (orthorhombic, Pbcm, a = 10.3807(7), b = 22.2341(19), c = 33.739(5) Å, V = 7787.2(14) Å3) has been solved by direct methods and refined to R1 = 0.107 on the basis of 3621 unique observed reflections. The structures of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16 are based upon sheets with the chemical composition [(UO2)3(SeO4)5]4‐. The sheets are formed by corner sharing between pentagonal bipyramids [UO7]8‐ and SeO42‐ tetrahedra. In the α‐modification, the [(UO2)3(SeO4)5]4‐ sheets are more or less planar and run parallel to (001). In the structure of the β‐modification, the uranyl selenate sheets are strongly corrugated and oriented parallel to (010). The [Mg(H2O)6]2+ polyhedra reside in the interlayers and provide three‐dimensional linkage of the uranyl selenate sheets via hydrogen bonding. In addition to H2O groups attached to Mg2+ cations, both structures also contain H2O molecules that are not bonded to any cation. The [(UO2)3(SeO4)5]4‐ sheets in the structures of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16 represent two different structural isomers. The sequences of the orientations of the tetrahedra within the sheets can be described by their orientational matrices with their shortened forms (ddudd□/uu□uud) and (dd□dd□uu□uu□/uuduumdduddm) for α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16, respectively. A short review on the isomerism of [(UO2)3(TO4)5]4‐ sheets (T = S, Cr, Se, Mo) is given.
Synthese, Strukturen, NMR‐ und EPR‐spektroskopische Untersuchungen an Übergangsmetallkomplexen monofluorsubstituierter Acylselenoharnstoffliganden
Authors: Kampf Michael , Richter Rainer , Hennig Lothar , Eidner Andreas , Baldamus Jens , Kirmse Reinhard
Published: December 2004

Die Synthesen und die Kristallstrukturen des Liganden N, N‐Diethyl‐N′‐(2‐fluor)benzoylselenoharnstoff HEt2mfbsu und dessen NiII‐ und ZnII‐Komplexen sowie des Liganden N, N‐Diisobutyl‐N′‐(2‐fluor)benzoylselenoharnstoff HBui2mfbsu und dessen NiII‐ und PdII‐Komplexen werden berichtet. Die Liganden koordinieren zweizähnig unter Bildung von Bischelaten. Der PdII‐ und die NiII‐Komplexe sind planar koordiniert und cis‐konfiguriert; [ZnII(Et2mfbsu)2] ist tetraedrisch koordiniert. Die Struktur des ebenfalls erhaltenen Bis[diisobutylamino‐(2‐fluorbenzoylimino)methyl]diselenids wird vorgestellt. Die CuII‐Komplexe beider Liganden konnten nicht isoliert werden. EPR‐Untersuchungen an den als Öle anfallenden Komplexen bestätigen jedoch eindeutig das Vorliegen der CuII‐Bischelate. Detaillierte NMR‐spektroskopische Untersuchungen ‐ 1H‐, 13C‐ und 19F‐COSY, HMBC und HMQC ‐ an [MII(Et2mfbsu)2] (M = NiII, ZnII) erlauben eine exakte Zuordnung aller Signale zu den magnetisch aktiven Kernen der Komplexe.
Complex Tellurium Salts with Supramolecular Bidimensional Lattices: Synthesis and X‐ray Characterization of (2‐Br‐C5NH5)2[TeX6] (X = Cl, Br)
Authors: Fernandes Ramão Marceli , de Oliveira Gelson Manzoni , Schulz Lang Ernesto , Vázquez‐López Ezequiel M.
Published: December 2004

The reaction of tellurium(IV) tetrahalides with hydrochloric and hydrobromic acid leads to the formation of (H3O)2[TeX6], which reacts subsequently with (2‐Br‐C5NH5)+X‐ to afford (2‐Br‐C5NH5)2[TeCl6] (1) and (2‐Br‐C5NH5)2[TeBr6] (2). The structure of the complex salts were analysed by X‐ray diffractometry affording the centrosymmetric space groups P21/n (monoclinic, 1) and P1¯ (triclinic, 2). Interionic hydrogen bondings hold their lattices in bidimensional supramolecular arrays not yet described in the literature. The lone electron pair of the AX6E‐system of the hexahalotellurates [TeX6]2‐ (X = Cl, Br) seems to be fully delocalized since only small octahedral deviations were observed for the anionic species. The structures of the title compounds were refined with the Te atoms occupying sites with full point symmetry, approximately m3¯m. In both cases the Te atoms enclose centers of inversion and the octahedrally dynamic structures are enforced and stabilized along the supramolecular lattices by the crystal field of the 2‐Br‐pyridinium cations.
Cyclic Iminoboranes: Analogues of Cycloalkynes
Authors: Münster Jochen , Paetzold Peter , Schröder Ernst , Schwan Heinrich , von Bennigsen‐Mackiewicz Theo
Published: December 2004

1‐Azido‐ and 1‐[trimethylsilyl(trimethylsilyloxy)]boracycloalkanes, (‐Y‐BX‐) [X = N3 (2), N(OSiMe3)SiMe3 (3), Y = alkanediyl], were synthesized from the corresponding chloroboranes [X = Cl (1)]. The following alkanediyl ring fragments were considered: Y = ‐CH2‐CHMe‐CH2‐CH2‐ (a), 1, 5‐cyclooctanediyl (b), ‐(CH2)6‐ (c), ‐(CH2)7‐ (d), ‐CMe2‐(CH2)6‐ (e), ‐C(‐CMe2‐CH2‐)‐(CH2)6‐ (f). The thermal elimination of N2 (from 2) or (SiMe3)2O (from 3) is accompanied by the migration of one of the two alkanediyl ends from boron to nitrogen under ring expansion to give the cyclic iminoboranes 4. Formed in solution, the iminoboranes react immediately with undecomposed starting material 2 or 3 under formation of the products 5 or 6 by azidoboration or aminoboration, respectively, of the BN multiple bond. The temperature for the decomposition of 2 depends on the ring size: the five‐membered ring compound 2a and the bicyclic six‐membered ring compound 2b decompose beneath 0 °C, the seven‐ and eight‐membered ring compounds 2c and 2d in boiling hexane and toluene, respectively, whereas the eight‐membered ring compounds 2e and 2f are decomposed in solution above 100 °C so slowly that only unidentified polymers are found. The boranes 3a and 3b, stable at room temperature, afford a temperature of 80 °C for decomposition in solution. The azidoboranes 2c‐f can be transported into the gas‐phase without decomposition and can be thermolyzed there at 270‐285 °C. The cyclic iminoboranes 4c‐e, formed in the hot tube, were condensed at ‐196 °C, but thereafter not characterized, because they either cyclotrimerized (4c, d) or cyclodimerized (4e, e′; two isomers depending on which end of the 1, 1‐dimethylheptamethylene unit migrates) beneath ‐60 °C under formation of the corresponding borazines 10c, d or of the diazadiboretidine isomer mixture 9e, e′, respectively; the spirocyclic borane 2f gives a mixture of unidentified products on gas‐phase thermolysis. The iminoboranes 4e, e′ can be trapped by ethyloboration with BEt3 giving the products 8e, e′. The acyclic azidoborane R(Me)BN3 (2g; R = 1‐methylcycloheptyl), formed after the ring‐contracting rearrangement of a boracyclooctane derivative, gives the isolated and characterized mixture of the acyclic iminoboranes MeB≡NR (4g) and RB≡NMe (4g′) upon gas‐phase thermolysis; the stabilization of 4g, g′ gives the Dewar borazines 11g and 11g′.
Synthese und Struktur von (PPh4)3[Re2NCl10]
Authors: Schwarz Simon , Strähle Joachim
Published: December 2004

Der Rhenium(V)nitrido‐Komplex (PPh4)3[Re2NCl10] (1) entsteht bei der Reaktion von (PPh4)[ReNCl4] mit 1, 3‐Dioxan‐(2‐ylmethyl)diphenylphosphan in CH2Cl2/CH3CN in Form orangeroter, solvathaltiger Kristalle. Er kristallisiert als 1·2CH2Cl2 in der triklinen Raumgruppe P1¯ mit a = 1210, 7(2); b = 1232, 5(1); c = 2756, 3(5) pm; α = 99, 68(1)°; β = 100, 24(1)°; γ = 98, 59(1)° und Z = 2. In der Kristallstruktur liegen zwei symmetrieunabhängige, zentrosymmetrische Komplexanionen [Re2NCl10]3‐ mit symmetrischen Nitridobrücken Re=N=Re und Abständen Re(1) ‐ N(1) = 181, 34(5) und Re(2) ‐ N(2) = 181, 51(4) pm vor.
Interplay of Electronic Structure and Bulk Properties in 2D and 3D Ternary Carbonitrides from First Principles
Authors: Betranhandy E. , Matar Samir F. , El‐Kfoury Ch. , Weihrich R. , Etourneau J.
Published: December 2004

The changes in electronic structure and hardness as inferred from the bulk modulus are investigated for model structures of ternary compounds XC3N3 (X = B, Al, P, As, Ga) within the framework of density functional theory (DFT). The optimisations of the proposed two‐ (2D) and three‐dimensional (3D) structures and the calculations of the bulk moduli are performed by a pseudo potential method. The electronic structures are calculated with the augmented sphere wave method (ASW). The obtained hardness for 2D BC3N3 system (B0 ∼ 220 GPa) points to a magnitude close to that of graphitic C3N4. For heavier X atoms it decreases rapidly. This is equally observed for the 3D systems examined in the β‐C3N4 structure for which B0(β‐BC3N3) amounts to ∼330 GPa. Within the magnitude of the well known hard material cubic BN, the BC3N3 phases can be predicted as candidates for ultra hard materials. The electronic effect induced by the chemical nature of the X substitutional was examined according to its position in the periodic table i.e. XIII or XV. Both, band structures and the electron localisation function (ELF) were used for this analysis. The ELF plots show a decreasing covalency with heavier X‐atoms. Potential applications of the devised systems are proposed such as dopings with atoms (Li, rare gas) and molecules (N2).
Computational Design of Hybrid Frameworks: Structure and Energetics of Two Me3OF3{‐O2C‐C6H4‐CO2‐}3 Metal‐Dicarboxylate Polymorphs, MIL‐hypo‐1 and MIL‐hypo‐2
Authors: Mellot‐Draznieks C. , Dutour Julien , Férey Gérard
Published: December 2004

The present paper aims at exploring the candidate hybrid structures of the Cr/trimesic acid system by assembling pre‐defined hybrid building‐blocks in direct space. Two possible hybrid building‐blocks were identified where the connection of the 1, 4 BDC molecules to an inorganic metal‐containing trimer forms a large supertetrahedron (ST) or alternatively a large supercube (SC). From existing topologies derived from the space filling packing of corner‐sharing cubes and tetrahedra, two candidates hybrid crystal structures were constructed. Lattice energy minimizations were performed on each candidate structure, as a preliminary step towards the estimation of their relative stabilities. This work further illustrates the computational design of very open hybrid frameworks using the concept of pre‐defined building blocks and their assembly in 3D space.
Maple syrup urine disease 1954 to 1993
Authors: Peinemann F. , Danner D. J.
Published: December 2004

The clinical, molecular genetic and other biochemical aspects of branched‐chain α‐ketoacid dehydrogenase defects are reviewed.
Chondrodysplasia punctata with a mild clinical course
Authors: Nuoffer J. M. , Pfammatter J. P. , Spahr A. , Toplak H. , Wanders R. J. A. , Schutgens R. B. H. , Wiesmann U. N.
Published: December 2004

We report a 7‐year‐old patient with chondrodysplasia punctata but without rhizomelia. He was born with typical clinical and radiological symptoms of this disease. He developed slowly with considerable psychomotor retardation but improved later, gaining some speech and psychosocial contacts. Joint contractures and bilateral cataracts are still major problems.De novo plasmalogen synthesis in fibroblasts was greatly reduced and DHAP‐AT activity was at the lower limit of controls. Peroxisomal thiolase was present in its precursor form only. Membrane fluidity (measured by TMA‐DPH fluorescence anisotropy) was increased in erythrocyte ghosts and in lymphocytes. Plasma phytanic acid concentration was elevated 5‐fold. The patient represents a mild clinical course of chondrodysplasia punctata, resembling Conradi‐Hünermann syndrome, but biochemically he has the typical peroxisomal dysfunction of rhizomelic chondrodysplasia punctata except for a high residual activity of DHAP‐AT.
The N370S mutation in the glucocerebrosidase gene of Portuguese type 1 Gaucher patients: Linkage to the PvuII polymorphism
Authors: Lacerda L. , Amaral O. , Pinto R. , Aerts J. , Sá Miranda M. C.
Published: December 2004

The mutation N370S accounts for 63% of the mutated glucocerebrosidase alleles of Portuguese type 1 Gaucher patients. It has been shown previously that this mutation is linked to the Pv1.1− form of the PvuII polymorphism and suggested that the N370S mutation in glucocerebrosidase alleles has an Ashkenazi Jewish origin. We have found that in Portuguese type 1 Gaucher patients this mutation is also invariably associated with the Pv1.1− haplotype, despite the fact that there is no evidence of Ashkenazi Jewish background in this population.
Sjögren‐Larsson syndrome: Nuclear magnetic resonance imaging of the brain in a 4‐year‐old boy
Authors: Di Rocco M. , Filocamo M. , Tortori‐Donati P. , Veneselli E. , Borrone C. , Rizzo W. B.
Published: December 2004

Magnetic resonance imaging of the brain of a 4‐year‐old patient with fatty alcohol: NAD+ oxidoreductase deficiency (Sjögren‐Larsson syndrome) showed a severe leukodystrophy.
The DNA methylation events in normal and cloned rabbit embryos
Authors: Chen Tao , Zhang Yan-Ling , Jiang Yan , Liu Shu-Zhen , Schatten Heide , Chen Da-Yuan , Sun Qing-Yuan
Published: December 2004

To study the DNA methylation events in normal and cloned rabbit embryos, we investigated the methylation status of a satellite sequence and the promoter region of a single‐copy gene using bisulfite‐sequencing technology. During normal rabbit embryo development, both sequences maintained hypermethylation status until the 8‐ to 16‐cell stage when progressive demethylation took place. In cloned embryos, the single‐copy gene promoter sequence was rapidly demethylated and precociously de novo methylated, while the satellite sequence maintained the donor‐type methylation status in all examined stages. Our results indicate that unique sequences as well as satellite sequences may have aberrant methylation patterns in cloned embryos.
Reine Psychologie, Angewandte Psychologie und die Institutionalisierung der Psychologie
Authors: Gundlach Horst
Published: December 2004

Zusammenfassung. Bezweifelt wird die überkommene Darstellung der Angewandten Psychologie als eines Sprösslings der Reinen, in der Universität forschenden Psychologie. Das Universitätsfach Psychologie verdankt seine Entstehung vielmehr erst Anwendungsabsichten. Zur Begründung dieser Aussage ist die Unterscheidung zwischen dem Fach (oder der Disziplin) Psychologie und dem Gebiet Psychologie erforderlich. Das Fach Psychologie entstand im Zusammenhang der Bildungsreformen des beginnenden 19. Jahrhunderts, die der Philosophischen Fakultät die Ausbildung der Gymnasiallehrer übertrugen. Psychologie sollte Fachwissen für den Lehrerberuf liefern und wurde deshalb als Lehr- wie Prüfungsfach institutionalisiert. Als zu Beginn des 20. Jahrhunderts eine Angewandten Psychologie gefordert wurde, ging es darum, das Fach Psychologie nach dem Muster der Lehrerausbildung auch in Ausbildungsgänge anderer Berufe einzubauen. Unvorhergesehen entstand jedoch im 20. Jahrhundert eine Profession, die sich primär durch die Ausbildung im Fach Psychologie definiert, das Fach umwandelte und heute die Entstehung Angewandter Psychologen als Zweck des Faches erscheinen lässt. Damit verknüpfte sich die Illusion des Ursprungs der Angewandten aus einer angeblich Reinen Psychologie.