bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of the human motor‐related thalamic nuclei during the first half of gestation, with special emphasis on GABAergic circuits
Authors: Kultas‐Ilinsky Kristy , Fallet Catherine , Verney Catherine 
Published: July 2004

AbstractThis study analyzed the expression of differentiation markers (Calbindin D28K: CaBP; parvalbumin: PARV; calretinin: CalR), gamma‐aminobutyric acid (GABA) markers (GABA, glutamic acid decarboxylases: GAD65, GAD67; and GABA transporters: GAT1, GAT3), and other markers (neurotensin: NT, and neurofilament‐specific protein: SMI32) in the human thalamus at 8–23 gestation weeks (g.w.), focusing on the motor‐related nuclei. From 8–13 g.w. mainly CaBP was expressed in the cells while fiber bundles traversing the thalamus in addition to CaBP expressed all GABA markers except GAD67. CaBP and PARV expression patterns in different nuclei changed over the time course studied, whereas NT was expressed consistently along the anterior‐lateral curvature of the thalamus. CalR and SMI were detectable at 23 g.w. in the ventral parts of the dorsal thalamus. Most remarkably, punctate GAD65 immunoreactivity in the neuropil was confined to the nigro‐ and pallidothalamic afferent receiving nuclei from 16 to about 21 g.w., overlapping with that of CaBP in some of these nuclei (subdivisions of the ventral anterior and mediodorsal nuclei) and with PARV in others (centromedian nucleus). During this period, GAD65 immunoreactivity can be considered a marker of the basal ganglia afferent receiving territory in the motor thalamus. GAD67‐positive local circuit neurons were first detected at 12–13 g.w. in the thalamic nuclei outside the basal ganglia afferent receiving territory. In the ventral anterior and centromedian nuclei, GAD‐containing local circuit neurons were not conspicuous even at 22–23 g.w. The cells of the reticular nucleus expressed GAD67 and PARV from 12 g.w. on starting in the lateral‐posterior regions. By 23 g.w., both markers were expressed in about two‐thirds of the nucleus except for its most medial‐anterior part. The results imply spatially and temporally differential expression of GABA and differentiation markers in the developing human thalamus. J. Comp. Neurol. 476:267–289, 2004. © 2004 Wiley‐Liss, Inc.
Subventricular zone‐derived neuronal progenitors migrate into the subcortical forebrain of postnatal mice
Authors: De Marchis Silvia , Fasolo Aldo , Puche Adam C. 
Published: July 2004

AbstractThe presence of a germinal layer and the capacity to generate neurons, once thought restricted to the embryonic brain, persists in the forebrain of both postnatal and adult mammals. The two regions in which this phenomenon has been extensively demonstrated are the hippocampal dentate gyrus and the lateral ventricle subventricular zone (SVZ). SVZ‐derived cells migrate along the rostral migratory stream into the olfactory bulb, where they differentiate into local interneurons. In this study, using tracer injections into the SVZ at different postnatal ages, we investigated the occurrence of secondary migratory pathways in the mouse subcortical forebrain. During the course of the first week postnatal, in addition to the well‐characterized rostral migratory stream, SVZ‐derived progenitors migrate in a ventral migratory mass across the nucleus accumbens into the basal forebrain and along a ventrocaudal migratory stream originating at the elbow between the vertical and horizontal limbs of the rostral migratory stream. These cells give rise to granule neurons in the Islands of Calleja and olfactory tubercle pyramidal layer, respectively. In adult, a very small number of cells continue to migrate along the ventrocaudal migratory stream, whereas no migration was observed across the nucleus accumbens. These data demonstrate that in early postnatal and, to a minor extent in adult mice, SVZ‐derived cells contribute new neurons to the subcortical forebrain. J. Comp. Neurol. 476:290–300, 2004. © 2004 Wiley‐Liss, Inc.
Axonogenesis in the medaka embryonic brain
Authors: Ishikawa Yuji , Kage Takahiro , Yamamoto Naoyuki , Yoshimoto Masami , Yasuda Takako , Matsumoto Atsuko , Maruyama Kouichi , Ito Hironobu 
Published: July 2004

AbstractIn order to know the general pattern of axonogenesis in vertebrates, we examined axonogenesis in the embryonic brain of a teleost fish, medaka (Oryzias latipes), and the results were compared with previous studies in zebrafish and mouse. The axons and somata were stained immunocytochemically using antibodies to a cell surface marker (HNK‐1) and acetylated tubulin and visualized by retrograde and anterograde labeling with a lipophilic dye. The fiber systems developed correlating with the organization of the longitudinal and transverse subdivisions of the embryonic brain. The first axons extended from the synencephalic tegmentum, forming the first fiber tract (fasciculus longitudinalis medialis) in the ventral longitudinal zone of the neural rod, 38 hours after fertilization. In the neural tube, throughout the entire brain two pairs of longitudinal fiber systems, one ventral series and one dorsal or intermediate series, and four pairs of transverse fiber tracts in the rostral brain were formed sequentially during the first 16 hours of axon production. In one of the dorsal longitudinal tracts, its branch retracted and disappeared at later stages. One of the transverse tracts was found to course in the telencephalon and hypothalamus. The overall pattern of the longitudinal fiber systems in medaka brain is similar to that in mouse, but apparently different from that in zebrafish. We propose that a ventral tract reported in zebrafish partially belongs to the dorsal fiber system, and that the longitudinal fiber systems in all vertebrate brains pass through a common layout defined by conserved genetic and developmental programs. J. Comp. Neurol. 476:240–253, 2004. © 2004 Wiley‐Liss, Inc.
Differentiation of the midbrain dopaminergic pathways during mouse development
Authors: Hu Zhaoliang , Cooper Margaret , Crockett David P. , Zhou Renping 
Published: July 2004

AbstractDopaminergic (DA) neurons in the substantia nigra (SN) and ventral tegmental area (VTA) of the midbrain project to the dorsolateral caudate/putamen and to the ventromedially located nucleus accumbens, respectively, establishing the mesostriatal and the mesolimbic pathways. Disruptions in this system have been implicated in Parkinson's disease, drug addiction, schizophrenia, and attention deficit hyperactivity disorder. However, progress in our understanding has been hindered by a lack of knowledge of how these pathways develop. In this study, different retrograde tracers, placed into the dorsolateral caudate/putamen and the nucleus accumbens, were used to analyze the development of the dopaminergic pathways. In embryonic day 15 mouse embryos, both SN and VTA neurons, as well as their fibers, were doubly labeled by striatal injections into the dorsolateral and ventromedial striatum. However, by birth, the SN DA neurons were labeled exclusively by DiA placed in the dorsolateral striatum, and the VTA DA neurons were labeled only by DiI injected into the ventromedial striatum. These data suggest that initial projections from midbrain DA neurons target nonspecifically to both the dorsolateral striatum and the nucleus accumbens. Later during development, the separate mesostriatal and mesolimbic pathways differentiate through the selective elimination of mistargeted collaterals. J. Comp. Neurol. 476:301–311, 2004. © 2004 Wiley‐Liss, Inc.
On the Bond‐Stretch Isomerism in the Benzo[1,2:4,5]dicyclobutadiene System—An ab initio MR‐AQCC Study
Authors: Antol Ivana , Eckert‐Maksić Mirjana , Lischka Hans , Maksić Zvonimir B. 
Published: July 2004

AbstractBond‐stretch isomerism in benzo[1,2:4,5]dicyclobutadiene (BDCB) has been investigated using the MR‐AQCC/6–31G(d) method, a high‐level multireference ab initio approach including size‐extensivity corrections. The applied theoretical approach includes both nondynamical and dynamical electron correlation effects. Full MR‐AQCC geometry optimizations of localized (1) and delocalized (3) isomers as well as the transition structure (TS) have been determined using D2h symmetry restriction. The calculations show that both isomers are approximately of equal stability separated by a barrier with a height of about 5 kcal mol−1. Thus, the present results strongly indicate that benzo[1,3:4,5]dicyclobutadiene is a very good candidate for an organic compound exhibiting bond‐stretch isomerism, since isomers 1 and 3 correspond to true minima on the double‐well potential energy surface, which are separated by a sufficiently high barrier. It is particularly important to emphasize that isomer 3 represents a realization of the highly elusive quasi‐[10]annulene.
Two‐Photon Absorption in Linear Bis‐dioxaborine Compounds—The Impact of Correlation‐Induced Oscillator‐Strength Redistribution
Authors: Zojer Egbert , Wenseleers Wim , Halik Marcus , Grasso Cara , Barlow Stephen , Perry Joseph W. , Marder Seth R. , Brédas Jean‐Luc 
Published: July 2004

AbstractQuantum‐chemical calculations of the two‐photon absorption (TPA) cross‐sections are used to determine the characteristics of the electronic excited states responsible for the observed peaks in the TPA spectra of two bis‐dioxaborine‐substituted biphenyl derivatives. We find two distinct TPA‐active states with very different TPA cross‐sections; the difference is explained on the basis of electron correlation. These effects, on the one hand, lead to TPA cross‐sections of up to 500×10−50 cm4 s photon−1 for the state favored by correlation; on the other hand, they limit the overall cross‐sections achievable in this class of materials.
Direct Measurement of Dynamic Frequency Shift Induced by Cross‐Correlations in 15N‐Enriched Proteins
Authors: Desvaux Hervé , Kümmerle Rainer , Kowalewski Jozef , Luchinat Claudio , Bertini Ivano 
Published: July 2004

AbstractWe describe a new NMR experimental scheme that allows the direct determination of the dynamic frequency shift induced by chemical shift anisotropy/dipolar interaction (CSA/DD) cross‐correlations in 15N‐enriched proteins. Its principle consists of comparing two rates of polarisation transfer between the amide proton and nitrogen. The first rate, which is independent of the dynamic frequency shift, is based on a selective Hartmann–Hahn coherence transfer. The second rate, which depends on the dynamic frequency shift, is based on a free evolution of the transverse magnetisation. We report experimental validation of this approach by measuring the average dynamic frequency shift due to CSA/DD cross‐correlations in the calcium‐binding protein D9k. The method may also be applicable to the measurement of dynamic frequency shift induced by cross‐correlations between the Curie spin and dipolar interactions.
Scanning Force Microscopy Based Rapid Force Curve Acquisition on Supported Lipid Bilayers: Experiments and Simulations Using Pulsed Force Mode
Authors: Krüger Stephanie , Krüger Daniel , Janshoff Andreas 
Published: July 2004

AbstractIn situ pulsed force mode scanning force microscopy (PFM–SFM) images of phase separated solid‐supported lipid bilayers are discussed with the help of computer simulations. Simultaneous imaging of material properties and topography in a liquid environment by means of PFM–SFM is severely hampered by hydrodynamic damping of the cantilever. Stiffness and adhesion images of solid‐supported membranes consisting of cholesterol, sphingomyelin, and 1,2‐dioleyl‐phosphatidylcholine obtained in aqueous solution exhibit contrast inversion of adhesion and stiffness images depending on parameters such as driving frequency, amplitude, and trigger setting. Simulations using a simple harmonic oscillator model explain experimental findings and give a deeper insight into the way PFM–SFM experiments have to be performed in order to obtain interpretable results and hence pave the way for reliable material contrast imaging at high speed.
Two‐Dimensional Double‐Quantum 2H NMR Spectroscopy in the Solid State under OMAS Conditions: Correlating 2H Chemical Shifts with Quasistatic Line Shapes
Authors: Hoffmann Anke , Schnell Ingo 
Published: July 2004

AbstractSolid‐state 2H NMR spectroscopy is a well‐established and versatile method to study molecular orientation and dynamics in selectively deuterated samples. Herein, we introduce a 2D 2H double‐quantum (DQ) NMR experiment performed under fast magic‐angle spinning with a slight offset of the magic angle (OMAS). The experiment combines 2H chemical‐shift resolution with DQ‐filtered quasistatic 2H line shapes. In this way, it is possible to separate 2H resonances and to independently determine 2H quadrupole couplings at multiple sites. While 2H chemical shifts are resolved in the 2H DQ dimension, the quadrupole parameters can be obtained from characteristic line shapes which are reintroduced in the second dimension by the magic‐angle offset. The 2D 2H DQ OMAS experiment is demonstrated on L‐histidine which was deuterated at multiple sites by recrystallisation from D2O.
Amorphous Silica as a Versatile Supermolecular Ligand for NiII Amine Complexes: Toward Interfacial Molecular Recognition
Authors: Boujday Souhir , Lambert Jean‐François , Che Michel 
Published: July 2004

AbstractSelective adsorption of NiII amine complexes used as precursors for supported catalysts was studied on amorphous silica surfaces. The nature of the adsorption sites was probed by [Ni(en)(dien)(H2O)]2+, [Ni(en)2(H2O)2]2+, and [Ni(dien)(H2O)3]2+ (en=ethylenediamine, dien=diethylenetriamine), which respectively contain one, two, and three labile aqua ligands. The silica surface acts as a mono‐ or polydentate ligand that can substitute the aqua ligands of the NiII complexes in an inner‐sphere adsorption mechanism. Room‐temperature adsorption isotherms indicate that each nickel complex selects a limited number of adsorption sites; different sites are recognised by the three complexes, even though they have the same charge and comparable sizes. Several spectroscopic techniques (UV/Vis/NIR, EXAFS, and 29Si NMR) were used to confirm the selective character of the interaction of NiII amine complexes with the silica surface. The specific sites include both silanol/silanolate groups in the same number as the original labile ligands and other surface groups that probably act as hydrogen‐bond acceptors. These two types of groups cooperate to result in interfacial molecular‐recognition phenomena with interactional complementarity.
Microsolvation of Phthalocyanines in Superfluid Helium Droplets
Authors: Lehnig Rudolf , Slenczka Alkwin 
Published: July 2004

AbstractExperimental and theoretical investigations of the spectroscopy of molecules in superfluid helium droplets provide evidence for the key role of the first helium layer surrounding the dopant molecule in determining the molecule's spectroscopic features. Recent investigations of emission spectra of phthalocyanine in helium droplets revealed a doubling of all transitions. Herein, we present the emission spectra of Mg‐phthalocyanine and of phthalocyanine–argon clusters in helium droplets, which confirm the splitting as a general effect of the helium environment. A scheme of levels is deduced from the emission spectra and attributed to quantized states of the first helium layer surrounding the dopant molecule.
Morphology and Nanomechanics of Conducting Plastic Crystals
Authors: Volel Maritza , Alarco Pierre‐Jean , Abu‐Lebdeh Yaser , Armand Michel 
Published: July 2004

AbstractWe present a temperature‐controlled scanning probe microscopy characterisation of morphology and mechanical behaviour of conducting N,N′‐cyclized pyrazolium salts. These salts are plastic crystals belonging to the pyrazolium trifluoromethanesulfonimide family. Going from a five‐membered to a seven‐membered ring, and adding a methyl group in α to either the five‐membered or six‐membered rings, allows modulation of the temperature of the phase transitions. Before and after the transitions, the materials' Young moduli, hardnesses and surface roughnesses change. We attribute these macroscopic modifications to specific states: brittle, elastoplastic and viscoplastic, corresponding to variations in the extent of the dislocations present in the crystal lattice planes of the compounds.
2003 Nobel Prize in Physics for Theoretical Work on Superfluid 3He
Authors: Leggett Anthony J. 
Published: July 2004

AbstractThe element helium comes in two (stable) forms, 4He and 3He; at low temperatures and pressures both form liquids rather than solids. The liquid phase of the common isotope, 4He, was realized nearly a century ago, and since 1938 has been known to show, at temperatures below about 2 K, the property of superfluidity—the ability to flow through the narrowest capillaries without apparent friction. The light isotope, 3He, is believed to be of quite a different nature; however,because of its similarity to the electrons in metals, which at low temperatures sometimes form “Cooper pairs” and thereby become superconducting, theorists in the 1960s and early 1970s had speculated that something similar might happen in liquid 3He, which would then also show superfluidity though for reasons rather different than 4He. In 1972 nuclear magnetic resonance (NMR) experiments at Cornell University revealed the existence, below 3 millidegrees, if two new phases, one of which displayed extraordinary NMR properties. Anthony Leggett is one of the theorists who succeeded in fitting the experimental properties into the “Cooper‐pairing” scenario; in particular, he explained the NMR behavior and predicted further novel NMR phenomena which were subsequently found.
Type H Superconductors and the Vortex Lattice
Authors: Abrikosov Alexei A. 
Published: July 2004

AbstractSuperconducting material is used, for example, in magnetic resonance imaging for medical examinations and particle accelerators in physics. Knowledge about superfluid liquids can give us deeper insight into the ways in which matter behaves in its lowest and most ordered state. Work by the author on superconduction in liquid helium established the existence of type II superconductors and proved that vortex lattices exist in superfluid helium, in the presence of magnetic fields. He showed that the Ginzburg–Landau theory could be extended to include this “new” type of superconductors, which today are in common use. His work on phase transitions of these superconductors under the influence of magnetic fields was groundbreaking, although he has worked in many other areas since then. He was awarded the Nobel prize in 2003 “for pioneering contributions to the theory of superconductors and superfluids” with V. L. Ginzburg and A. J. Leggett.
Medical removal protection benefits: The special challenges of Beryllium
Authors: Abbotts John , Takaro Tim K. 
Published: July 2004

AbstractDuring the 1990s, the Department of Energy (DOE) established a Chronic Beryllium Disease Prevention Program and revised regulations for beryllium exposure to DOE and contractor employees. DOE beryllium regulations include “medical surveillance” of potentially exposed workers, along with “medical removal protection benefits” for beryllium‐sensitized workers. Medical removal benefits were first introduced into individual standards of the Occupational Safety and Health Administration (OSHA), beginning with a standard for asbestos in 1972. DOE modeled its medical removal protection benefits for beryllium in part on OSHA standards for lead and cadmium. But DOE also recognized significant differences in the toxicology of beryllium compared to these other metals. We survey OSHA standards for medical removal protection, provide a comparison with beryllium, and identify potential limits in beryllium protection benefits. © 2004 Wiley Periodicals, Inc.
Evaluation of the Digital Opacity Compliance System at military and commercial industrial sites
Authors: McFarland Michael J. , Stone Daniel A. , Rasmussen Steven L. , Calidonna Michael J. , Kerch Paul E. , Gunter Josh A. 
Published: July 2004

AbstractThe U.S. Environmental Protection Agency (EPA) has established EPA Reference Method 9 (Method 9) as the preferred enforcement approach for verifying compliance with federal visible opacity standards. The costs associated with maintaining Method 9 certification, including tuition fees, attendee's travel, and the three days of missed work every six months, supports the claim that the Method 9 program is expensive. Beyond the economic burden associated with Method 9 certification, its reliance on human observers to quantify visible opacity is inherently subjective, a characteristic that exposes the results to claims of inaccuracy, bias, and/or outright fraud.The Digital Opacity Compliance System (DOCS) has been proposed as a scientifically defensible alternative to Method 9. Field application of the DOCS at military and commercial industrial facilities has demonstrated that the accuracy of the DOCS in measuring plume opacity is not only comparable to Method 9–certified human observers but that the DOCS also provides a permanent digital image of the plume that can be easily referenced in challenging enforcement actions. © 2004 Wiley Periodicals, Inc.
Managing problem indoor environments by embracing subjective data: A case study for federal facilities
Authors: Thomas‐Mobley Linda , Oberle Rita 
Published: July 2004

AbstractThis article describes a new approach to embrace the multifaceted nature of “sick buildings” by analyzing industrial hygienist measurements, which are objective, along with occupant perception measurements, which are subjective, using a neural network–based model. Data, both objective and subjective, for this research were provided by the General Services Administration (GSA) on a wide variety of federal office buildings. Current literature on the subject suggests that the cause of poor indoor environments involves many variables interacting in an unlimited number of combinations. A blended definition of a narrowly defined “sick building” and a framework for a decision‐making support system is presented to help the building engineer better understand the complex nature of the indoor environment. The research and data analyses can be tailored to and applicable to any federal agency. © 2004 Wiley Periodicals, Inc.
Dynamical systems‐based optimal control of incompressible fluids
Authors: Hintermüller Michael , Kunisch Karl , Spasov Yulian , Volkwein Stefan 
Published: July 2004

AbstractFor optimal control problems related to fluid flow the choice of an adequate cost functional for suppression of vortices is of significant importance. In this research we propose a cost functional based on a local dynamical systems characterization of vortices. The resulting functional is a non‐convex function of the velocity gradient tensor. The resulting optimality system describing first order necessary optimality conditions is derived, a possible strategy for numerical realization of the optimal control problem is provided and a numerical feasibility study is conducted. Copyright © 2004 John Wiley & Sons, Ltd.