bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atomic Structure and Electrical Properties of In(Te) Nanocontacts on CdZnTe(110) by Scanning Probe Microscopy
Authors: Cohen‐Taguri Gili , Sinkevich Ori , Levinshtein Mario , Ruzin Arie , Goldfarb Ilan 
Published: November 2009

AbstractUnderstanding complex correlations between the macroscopic device performance (largely dependent on the character of the metal–semiconductor contact) and the metallurgy of contact formation on the atomic level in cadmium zinc telluride (CdZnTe) radiation detectors remains a formidable challenge. In this work, an effort towards bridging that macro–nano knowledge gap is made by conducting a series of controlled experiments aimed at correlating electrical properties of the In contact to n‐type CdZnTe(110) surface with the step‐by‐step process of contact formation. This can only be achieved by using high spatial resolution techniques, capable of conducting highly localized measurements on the nano‐ and sub‐nanoscale, such as scanning probe microscopy. Scanning tunneling microscopy is used in situ to monitor the behavior of various In atom coverages on an atomically flat and ordered CdZnTe surface under well‐controlled molecular beam epitaxial conditions in ultra‐high vacuum. Electrical derivatives of atomic force microscopy are used to measure the electrical contact properties, such as contact potential difference and spreading resistance in torsion resonance tunneling mode. It is concluded that In atoms preferentially reacted with Te atomic‐rows already at room temperature, forming nanometric patches of indium–telluride Schottky‐type contacts. The methods developed in this study, in terms of both nanocontact fabrication and characterization (especially in terms of electrical properties) should benefit basic and applied research of any metal–semiconductor system.
Multifunctional Fluorene‐Based Oligomers with Novel Spiro‐Annulated Triarylamine: Efficient, Stable Deep‐Blue Electroluminescence, Good Hole Injection, and Transporting Materials with Very High Tg
Authors: Jiang Zuoquan , Liu Zhongyin , Yang Chuluo , Zhong Cheng , Qin Jingui , Yu Gui , Liu Yunqi 
Published: November 2009

AbstractA series of fluorene‐based oligomers with novel spiro‐annulated triarylamine structures, namely DFSTPA, TFSTPA, and TFSDTC, are synthesized by a Suzuki cross‐coupling reaction. The spiro‐configuration molecular structures lead to very high glass transition temperatures (197–253 °C) and weak intermolecular interactions, and consequently the structures retain good morphological stability and high fluorescence quantum efficiencies(0.69–0.98). This molecular design simultaneously solves the spectral stability problems and hole‐injection and transport issues for fluorene‐based blue‐light‐emitting materials. Simple double‐layer electroluminescence (EL) devices with a configuration of ITO/TFSTPA (device A) or TFSDTC (device B)/ TPBI/LiF/Al, where TFSTPA and TFSDTC serve as hole‐transporting blue‐light‐emitting materials, show a deep‐blue emission with a peak around 432 nm, and CIE coordinates of (0.17, 0.12) for TFSTPA and (0.16, 0.07) for TFSDTC, respectively, which are very close to the National Television System Committee (NTSC) standard for blue (0.15, 0.07). The maximum current efficiency/external quantum efficiencies are 1.63 cd A−1/1.6% for device A and 1.91 cd A−1/2.7% for device B, respectively. In addition, a device with the structure ITO/DFSTPA/Alq3/LiF/Al, where DFSTPA acts as both the hole‐injection and ‐transporting material, is shown to achieve a good performance, with a maximum luminance of 14 047 cd m−2, and a maximum current efficiency of 5.56 cd A−1. These values are significantly higher than those of devices based on commonly usedN,N′‐di(1‐naphthyl)‐N,N′‐diphenyl‐[1,1′‐biphenyl]‐4,4′‐diamine (NPB) as the hole‐transporting layer (11 738 cd m−2 and 3.97 cd A−1) under identical device conditions.
Spatial patterns and evolutionary processes in southern South America: A study of dental morphometric variation
Authors: Bernal Valeria , Perez S. Ivan , Gonzalez Paula N. , Sardi Marina L. , Pucciarelli Héctor M. 
Published: November 2009

AbstractThe purpose of this article is to examine the patterns of evolutionary relationships between human populations from the later Late Holocene (1,500–100 years BP) of southern South America on the basis of dental morphometric data. We tested the hypotheses that the variation observed in this region would be explained by the existence of populations with different phylogenetic origin or differential action of gene flow and genetic drift. In this study, we analyzed permanent teeth from 17 samples of male and female adult individuals from throughout southern South America. We measured mesiodistal and buccolingual diameters at the base of the crown, along the cement–enamel junction. The results of multiple regression analysis and a mantel correlogram indicate the existence of spatial structure in dental shape variation, as the D2 Mahalanobis distance between samples increases with increasing geographical distance between them. In addition, the correlation test results show a trend toward reduction of the internal variation of samples with increasing latitude. The detected pattern of dental variation agrees with the one expected as an outcome of founder serial effects related to an expansion of range during the initial occupation of southern South America. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc.
Influence of microwave heating on the kinetic of acrylic acid polymerization and crosslinking
Authors: Jovanovic Jelena , Adnadjevic Borivoj 
Published: November 2009

AbstractKinetics of isothermal formation of poly (acrylic acid) (PAA) hydrogels through polymerization of acrylic acid and crosslinking of the PAA formed in a conventionally heated reaction system and in a microwave heated reaction system were investigated. It was found that in the microwave heated system the reaction rate constant of PAA hydrogel formation significantly increased (from 32 to 43 times) when compared with the conventionally heated system. The isothermal kinetics of the PAA hydrogel formation during the microwave process could be described by the so‐called first‐order chemical reaction kinetics model. In contrast, the so‐called second‐order chemical reaction rate model could best describe the isothermal kinetics of the PAA hydrogel formation during the conventionally heated process. Also, in the microwave heated system, the reaction kinetics of the PAA hydrogel formation and its kinetic parameters changed, that is, the activation energy (Ea) decreased by about 19% and the pre‐exponential factor (lnA) decreased by 2.2 times. The decrease in activation energy, change in entropy of activation energy, and decrease in the pre‐exponential value of PAA hydrogel formation under microwave heating are caused with increased energy of the reactive species when compared with their energy in thermal activation. Increased energy of the reactive species is a consequence of rapid transfer and absorption of the energy of microwave field to the existing reactive species. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
New Phylogenetic Analysis of the Family Elephantidae Based on Cranial‐Dental Morphology
Authors: Todd Nancy E. 
Published: November 2009

AbstractIn 1973, Vincent Maglio published a seminal monograph on the evolution of the Elephantidae, in which he revised and condensed the 100+ species named by Henry Fairfield Osborn in 1931. Michel Beden further revised the African Elephantidae in 1979, but little systematic work has been done on the family since this publication. With addition of new specimens and species and revisions of chronology, a new analysis of the phylogeny and systematics of this family is warranted. A new, descriptive character dataset was generated from studies of modern elephants for use with fossil species. Parallel evolution in cranial and dental characters in all three lineages of elephants creates homoplastic noise in cladistic analysis, but new inferences about evolutionary relationships are possible. In this analysis, earlyLoxodontaand early AfricanMammuthusare virtually indistinguishable in dental morphology. TheElephaslineage is not monophyletic, and results from this analysis suggest multiple migration events out of Africa into Eurasia, and possibly back into Africa. New insight into the origin of the three lineages is also proposed, withStegotetrabelodonleading to theMammuthuslineage, andPrimelephasas the ancestor ofLoxodontaandElephas. These new results suggest a much more complex picture of elephantid origins, evolution, and paleogeography. Anat Rec, 2010. © 2009 Wiley‐Liss, Inc.
Polarized Light Microscopic Analysis of Bone Formation After Inhibition of Cyclooxygenase 1 and 2
Authors: Retamoso Luciana Borges , Montagner Francisco , Camargo Elisa Souza , Vitral Roberto Willer Farinazzo , Tanaka Orlando Motohiro 
Published: November 2009

AbstractPotassium diclofenac is a potent nonsteroidal anti‐inflammatory drug (NSAID) and COX isoforms (COX‐1 and COX‐2) inhibitor. Quantitative analysis of birefringence with polarized light microscopy is a useful method to investigate the macromolecular orientation and organization of collagen fibers in connective tissues. The aim of this research was to analyze the collagen structure and maturation in bone formed after potassium diclofenac administration, during first molar orthodontic movement. Sixty Wistar rats were divided in two equal groups (N = 30): control (C) and potassium diclofenac (PD). The animals in Group C received 0.9% saline solution and the PD group received potassium diclofenac Cataflam® (5 mg/kg). Animals were sacrificed 3, 7, or 14 days after a NiTi unilateral closed‐coil spring was stretched between the upper right first molar and the incisors. The first molar area was fixed, decalcified, and histologically processed using picrosirius pigment. The collagen birefringence of bone turnover was analyzed by phase retardation. Two‐way ANOVA and Tukey's test showed that optical retardation was influenced by time and treatment. There was increase in the collagen organization over time. On the third day, the C group showed better collagen organization than the PD group. Potassium diclofenac interfered in collagen maturation, reducing fibril organization in the initial phase of orthodontic movement. Anat Rec, 2010. © 2009 Wiley‐Liss, Inc.
Platinum‐Decorated Ruthenium Nanoparticles for Enhanced Methanol Electrooxidation
Authors: Chen Ching‐Hsiang , Sarma Loka Subramanyam , Wang Di‐Yan , Lai Feng‐Ju , Al Andra Cun‐Cun , Chang Shi‐Hong , Liu Din‐Goa , Chen Chia‐Chun , Lee Jyh‐Fu , Hwang Bing‐Joe 
Published: November 2009

AbstractA promising electrocatalyst based on the reduction of Pt2+ ions on the surface of hexagonally close‐packed (hcp) Ru core nanoparticles has been prepared by a redox–transmetalation process. This simple synthetic process generates a Pt‐on‐Ru catalyst with a lower Pt content than commercially available PtRu electrocatalysts and with a long‐range ordered hcp structure, which can significantly reduce the Pt loading. X‐Ray absorption spectroscopy of the Pt‐on‐Ru catalyst reveals pronounced electronic modifications when compared to the commercial PtRu black catalyst. The Pt‐on‐Ru catalyst exhibits a higher mass‐specific current than the PtRu black catalyst in solution in 0.5 M H2SO4 with 10 vol. % CH3OH under the conditions of rotating disk experiments. Further optimization of this synthetic procedure may yield even more active electrocatalysts with a significant reduction in noble metal loadings.
Total Synthesis, Characterization, and Conformational Analysis of the Naturally Occurring Hexadecapeptide Integramide A and a Diastereomer
Authors: De Zotti Marta , Damato Francesca , Formaggio Fernando , Crisma Marco , Schievano Elisabetta , Mammi Stefano , Kaptein Bernard , Broxterman Quirinus B. , Felock Peter J. , Hazuda Daria J. , Singh Sheo B. , Kirschbaum Jochen , Brückner Hans , Toniolo Claudio 
Published: November 2009

AbstractIntegramide A is a 16‐amino acid peptide inhibitor of the enzyme HIV‐1 integrase. We have recently reported that the absolute stereochemistries of the dipeptide sequence near the C terminus are L‐Iva14‐D‐Iva15. Herein, we describe the syntheses of the natural compound and its D‐Iva14‐L‐Iva15 diastereomer, and the results of their chromatographic/mass spectrometric analyses. We present the conformational analysis of the two compounds and some of their synthetic intermediates of different main‐chain length in the crystal state (by X‐ray diffraction) and in solvents of different polarities (using circular dichroism, FTIR absorption, and 2D NMR techniques). These data shed light on the mechanism of inhibition of HIV‐1 integrase, which is an important target for anti‐HIV therapy.
The Interaction of Zinc(II) and Hydroxamic Acids and a Metal‐Triggered Lossen Rearrangement
Authors: Ducháčková Lucie , Roithová Jana 
Published: November 2009

AbstractThe structure and reactivity of a complex of zinc(II), water, acetic acid, and acetohydroxamic acid, in which one of the acids is deprotonated, is investigated by means of mass spectrometry, labeling studies, and density functional calculations to unravel the exceptional binding properties of hydroxamic acids towards zinc‐containing enzymes at the molecular level. It is shown that acetohydroxamic acid is deprotonated in the complex, whereas acetic acid is present in its neutral form. The binding energies of the ligands towards zinc increase in the following order: water<acetic acid<acetohydroxamic acid. The structure of the complex and its fragmentation provide experimental evidence for the proposed mode of operation of drugs based on hydroxamic acids. Furthermore, coordinatively unsaturated complexes of zinc and acetohydroxamic acid undergo a zinc‐assisted Lossen rearrangement followed by elimination of water if acetohydroxamic acid is present as a neutral ligand, or by loss of methylisocyanate if acetohydroxamic acid is deprotonated.
Altered balance of γ‐aminobutyric acidergic and glutamatergic afferent inputs in rostral ventrolateral medulla‐projecting neurons in the paraventricular nucleus of the hypothalamus of renovascular hypertensive rats
Authors: Biancardi Vinicia Campana , Campos Ruy Ribeiro , Stern Javier Eduardo 
Published: November 2009

AbstractAn imbalance of excitatory and inhibitory functions has been shown to contribute to numerous pathological disorders. Accumulating evidence supports the idea that a change in hypothalamic γ‐aminobutyric acid (GABA)‐ergic inhibitory and glutamatergic excitatory synaptic functions contributes to exacerbated neurohumoral drive in prevalent cardiovascular disorders, including hypertension. However, the precise underlying mechanisms and neuronal substrates are still not fully elucidated. In the present study, we combined quantitative immunohistochemistry with neuronal tract tracing to determine whether plastic remodeling of afferent GABAergic and glutamatergic inputs into identified RVLM‐projecting neurons of the hypothalamic paraventricular nucleus (PVN‐RVLM) contributes to an imbalanced excitatory/inhibitory function in renovascular hypertensive rats (RVH). Our results indicate that both GABAergic and glutamatergic innervation densities increased in oxytocin‐positive, PVN‐RVLM (OT‐PVN‐RVLM) neurons in RVH rats. Despite this concomitant increase, time‐dependent and compartment‐specific differences in the reorganization of these inputs resulted in an altered balance of excitatory/inhibitory inputs in somatic and dendritic compartments. A net predominance of excitatory over inhibitory inputs was found in OT‐PVN‐RVLM proximal dendrites. Our results indicate that, along with previously described changes in neurotransmitter release probability and postsynaptic receptor function, remodeling of GABAergic and glutamatergic afferent inputs contributes as an underlying mechanism to the altered excitatory/inhibitory balance in the PVN of hypertensive rats. J. Comp. Neurol. 518:567–585, 2010. © 2009 Wiley‐Liss, Inc.
Hind‐limb paraparesis in a rat model for neurolathyrism associated with apoptosis and an impaired vascular endothelial growth factor system in the spinal cord
Authors: Kusama‐Eguchi Kuniko , Yamazaki Yoshiko , Ueda Tadashi , Suda Atsuhiro , Hirayama Yukari , Ikegami Fumio , Watanabe Kazuko , May Mike , Lambein Fernand , Kusama Tadashi 
Published: November 2009

AbstractNeurolathyrism is a motor neuron disease characterized by lower limb paraparesis. It is associated with ingestion of a plant excitotoxin, β‐N‐oxalyl‐L‐αβ‐diaminopropionic acid (L‐β‐ODAP), an agonist of α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA)/kainate‐type glutamatergic receptors. Previously, a limited model of neurolathyrism was reported for the rat. To improve upon the model, we stressed rat pups by separation from their mothers, followed by the subcutaneous L‐β‐ODAP treatment, resulting in a 4.6‐fold higher incidence (14.0–15.6%) of the paraparesis compared with the prior study. The number and size of motor neurons in these rats were decreased only in the lumbar and sacral cord segments, at approximately 13–36 weeks after treatment. Only lumbar and sacral spinal cord tissue revealed pathological insults typical of physical and ischemic spinal cord injury in the surviving motor neurons. In addition, extensive but transient hemorrhage occurred in the ventral spinal cord parenchyma of the rat, and numerous TdT‐mediated dUTP‐biotin nick end‐labeling (TUNEL)‐positive cells were also observed. In parallel, vascular endothelial growth factor receptor (VEGFR)‐2 (Flk‐1) levels were significantly lowered in the lumbosacral spinal cord of the paraparetic rats compared with their controls, suggesting a failure of the VEGF system to protect neurons against L‐β‐ODAP toxicity. We propose, based on these data, a novel pathological process of motor neuron death induced by peripheral L‐β‐ODAP. For the first time, we present a model of the early molecular events that occur during chemically induced spinal cord injury, which can potentially be applied to other neurodegenerative disorders. J. Comp. Neurol. 518:928–942, 2010. © 2009 Wiley‐Liss, Inc.
Effects of incisor extraction on jaw and tongue motor representations within face sensorimotor cortex of adult rats
Authors: Avivi‐Arber Limor , Lee Jye‐Chang , Sessle Barry J. 
Published: November 2009

AbstractLoss of teeth is associated with changes in somatosensory inputs and altered patterns of mastication, but it is unclear whether tooth loss is associated with changes in motor representations within face sensorimotor cortex of rats. We used intracortical microstimulation (ICMS) and recordings of cortically evoked muscle electromyographic (EMG) activities to test whether changes occur in the ICMS‐defined motor representations of the left and right jaw muscles [masseter, anterior digastric (LAD, RAD)] and tongue muscle [genioglossus (GG)] within the cytoarchitectonically defined face primary motor cortex (face‐M1) and adjacent face primary somatosensory cortex (face‐S1) 1 week following extraction of the right mandibular incisor in anesthetized (ketamine‐HCl) adult male Sprague‐Dawley rats. Under local and general anesthesia, an “extraction” group (n = 8) received mucoalveolar bone surgery and extraction of the mandibular right incisor. A “sham‐extraction” group (n = 6) received surgery with no extraction. A “naive” group (n = 6) had neither surgery nor extraction. Data were compared by using mixed‐model repeated‐measures ANOVA. Dental extraction was associated with a significantly increased number of sites within face‐M1 and face‐S1 from which ICMS evoked RAD EMG activities, a lateral shift of the RAD and LAD centers of gravity within face‐M1, shorter onset latencies of ICMS‐evoked GG activities within face‐M1 and face‐S1, and an increased number of sites within face‐M1 from which ICMS simultaneously evoked RAD and GG activities. Our novel findings suggest that dental extraction may be associated with significant neuroplastic changes within the rat's face‐M1 and adjacent face‐S1 that may be related to the animal's ability to adapt to the altered oral state. J. Comp. Neurol. 518:1030–1045, 2010. © 2009 Wiley‐Liss, Inc.
Expression of vascular endothelial growth factor receptor‐3 mRNA in the rat developing forebrain and retina
Authors: Choi Jeong‐Sun , Shin Yoo‐Jin , Lee Ji‐Yeon , Yun Hou , Cha Jung‐Ho , Choi Jae‐Youn , Chun Myung‐Hoon , Lee Mun‐Yong 
Published: November 2009

AbstractVascular endothelial growth factor receptor (VEGFR)‐3, a receptor for VEGF‐C and VEGF‐D, is expressed in neural progenitor cells, but there has been no comprehensive study of its distribution in the developing brain. Here, the temporal and cell‐specific expression of VEGFR‐3 mRNA was studied in the developing rat forebrain and eye. Expression appeared along the ventricular and subventricular zones of the lateral and third ventricles showing ongoing neurogenesis as early as embryonic day 13 but was progressively down‐regulated during development and remained in the subventricular zone and rostral migratory stream of the adult forebrain. VEGFR‐3 expression was also detectable in some differentiating and postmitotic neurons in the developing cerebral cortex, including Cajal‐Retzius cells, cortical plate neurons, and subplate neurons. Expression in the subplate increased significantly during the early postnatal period but was absent by postnatal day 14. It was also highly expressed in nonneural tissues of the eye during development, including the retinal pigment epithelium, the retinal ciliary margin, and the lens, but persisted in a subset of cells in the pigmented ciliary epithelium of the adult eye. In contrast, there was weak or undetectable expression in the early neural retina, but a subset of retinal neurons in the postnatal and mature retina showed intense signals. These unique spatiotemporal mRNA expression patterns suggest that VEGFR‐3 might mediate the regulation of both neurogenesis and adult neuronal function in the rat forebrain and eye. J. Comp. Neurol. 518:1064–1081, 2010. © 2009 Wiley‐Liss, Inc.
Paraventricular hypothalamic nucleus: Axonal projections to the brainstem
Authors: Geerling Joel C. , Shin Jung‐Won , Chimenti Peter C. , Loewy Arthur D. 
Published: November 2009

AbstractThe paraventricular hypothalamic nucleus (PVH) contains many neurons that innervate the brainstem, but information regarding their target sites remains incomplete. Here we labeled neurons in the rat PVH with an anterograde axonal tracer, Phaseolus vulgaris leucoagglutinin (PHAL), and studied their descending projections in reference to specific neuronal subpopulations throughout the brainstem. While many of their target sites were identified previously, numerous new observations were made. Major findings include: 1) In the midbrain, the PVH projects lightly to the ventral tegmental area, Edinger‐Westphal nucleus, ventrolateral periaqueductal gray matter, reticular formation, pedunculopontine tegmental nucleus, and dorsal raphe nucleus. 2) In the dorsal pons, the PVH projects heavily to the pre‐locus coeruleus, yet very little to the catecholamine neurons in the locus coeruleus, and selectively targets the viscerosensory subregions of the parabrachial nucleus. 3) In the ventral medulla, the superior salivatory nucleus, retrotrapezoid nucleus, compact and external formations of the nucleus ambiguus, A1 and caudal C1 catecholamine neurons, and caudal pressor area receive dense axonal projections, generally exceeding the PVH projection to the rostral C1 region. 4) The medial nucleus of the solitary tract (including A2 noradrenergic and aldosterone‐sensitive neurons) receives the most extensive projections of the PVH, substantially more than the dorsal vagal nucleus or area postrema. Our findings suggest that the PVH may modulate a range of homeostatic functions, including cerebral and ocular blood flow, corneal and nasal hydration, ingestive behavior, sodium intake, and glucose metabolism, as well as cardiovascular, gastrointestinal, and respiratory activities. J. Comp. Neurol. 518:1460–1499, 2010. © 2009 Wiley‐Liss, Inc.