bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scene from above: Retinal ganglion cell topography and spatial resolving power in the giraffe (Giraffa camelopardalis)
Authors: Coimbra João Paulo , Hart Nathan S. , Collin Shaun P. , Manger Paul R. 
Published: November 2012

AbstractThe giraffe (Giraffa camelopardalis) is a browser that uses its extensible tongue to selectively collect leaves during foraging. As the tallest extant terrestrial mammal, its elevated head height provides panoramic surveillance of the environment. These aspects of the giraffe's ecology and phenotype suggest that vision is of prime importance. Using Nissl‐stained retinal wholemounts and stereological methods, we quantitatively assessed the retinal specializations in the ganglion cell layer of the giraffe. The mean total number of retinal ganglion cells was 1,393,779 and their topographic distribution revealed the presence of a horizontal visual streak and a temporal area. With a mean peak of 14,271 cells/mm2, upper limits of spatial resolving power in the temporal area ranged from 25 to 27 cycles/degree. We also observed a dorsotemporal extension (anakatabatic area) that tapers toward the nasal retina giving rise to a complete dorsal arch. Using neurofilament‐200 immunohistochemistry, we also detected a dorsal arch formed by alpha ganglion cells with density peaks in the temporal (14–15 cells/mm2) and dorsonasal (10 cells/mm2) regions. As with other artiodactyls, the giraffe shares the presence of a horizontal streak and a temporal area which, respectively, improve resolution along the horizon and in the frontal visual field. The dorsal arch is related to the giraffe's head height and affords enhanced resolution in the inferior visual field. The alpha ganglion cell distribution pattern is unique to the giraffe and enhances acquisition of motion information for the control of tongue movement during foraging and the detection of predators. J. Comp. Neurol. 521:2042–2057, 2013. © 2012 Wiley Periodicals, Inc.
Neurochemical characterization of neurons expressing melanin‐concentrating hormone receptor 1 in the mouse hypothalamus
Authors: Chee Melissa J.S. , Pissios Pavlos , Maratos‐Flier Eleftheria 
Published: November 2012

AbstractMelanin‐concentrating hormone (MCH) is a hypothalamic neuropeptide that acts via MCH receptor 1 (MCHR1) in the mouse. It promotes positive energy balance; thus, mice lacking MCH or MCHR1 are lean, hyperactive, and resistant to diet‐induced obesity. Identifying the cellular targets of MCH is an important step to understanding the mechanisms underlying MCH actions. We generated the Mchr1‐cre mouse that expresses cre recombinase driven by the MCHR1 promoter and crossed it with a tdTomato reporter mouse. The resulting Mchr1‐cre/tdTomato progeny expressed easily detectable tdTomato fluorescence in MCHR1 neurons, which were found throughout the olfactory system, striatum, and hypothalamus. To chemically identify MCH‐targeted cell populations that play a role in energy balance, MCHR1 hypothalamic neurons were characterized by colabeling select hypothalamic neuropeptides with tdTomato fluorescence. TdTomato fluorescence colocalized with dynorphin, oxytocin, vasopressin, enkephalin, thyrothropin‐releasing hormone, and corticotropin‐releasing factor immunoreactive cells in the paraventricular nucleus. In the lateral hypothalamus, neurotensin, but neither orexin nor MCH neurons, expressed tdTomato. In the arcuate nucleus, both Neuropeptide Y and proopiomelanocortin cells expressed tdTomato. We further demonstrated that some of these arcuate neurons were also targets of leptin action. Interestingly, MCHR1 was expressed in the vast majority of leptin‐sensitive proopiomelanocortin neurons, highlighting their importance for the orexigenic actions of MCH. Taken together, this study supports the use of the Mchr1‐cre mouse for outlining the neuroanatomical distribution and neurochemical phenotype of MCHR1 neurons. J. Comp. Neurol. 521:2208–2234, 2013. © 2012 Wiley Periodicals, Inc.
Nonlinear Optical Response of a Polymer Electret with Incorporated Organic Chromophores
Authors: Balakina Marina Yu. 
Published: November 2012

AbstractAn analytical approach aimed at modeling the nonlinear optical (NLO) response of a polymer electret with incorporated organic dipole chromophores is extended to the dynamic case. The approach allows the effect of the locally anisotropic, polarizable, deformable polymer matrix on the chromophore NLO response to be accounted for. The method exploits the original cavity ansatz according to which the virtual cavity occupied by the chromophore in the polymer matrix is chosen to be conformal to the characteristic ellipsoid of the generalized permittivity tensor. Analytical expressions for the dynamic electric moments of dipole chromophores and macroscopic polarization of a polymer electret at fundamental and second harmonic frequencies are obtained by using a computational scheme based on two self‐consistency procedures. On the basis of the expressions for dynamic macroscopic polarization, the analytical formulas for linear, ${\chi _j^{i(1)} (\omega )}$, and quadratic, ${\chi _{jk}^{i(2)} (2\omega )}$, electric susceptibilities are obtained. The presented expressions establish the relationship between the molecular polarizabilities of chromophores and the macroscopic electrical properties of the polymer electret.
Towards a Spectroscopic and Theoretical Identification of the Isolated Building Blocks of the Benzene–Acetylene Cocrystal
Authors: Böning Markus , Stuhlmann Benjamin , Engler Gernot , Busker Matthias , Häber Thomas , Tekin Adem , Jansen Georg , Kleinermanns Karl 
Published: November 2012

AbstractIsomer‐ and mass‐selective UV and IR–UV double resonance spectra of the BA3, B2A, and B2A2clusters of benzene (B) and acetylene (A) are presented. Cluster structures are assigned by comparison with the UV and IR spectra of benzene, the benzene dimer, as well as the BA, BA2, and B2A clusters. The intermolecular vibrations of BA are identified by dispersed fluorescence spectroscopy. Assignment of the cluster structures is supported by quantum chemical calculations of IR spectra with spin‐component scaled second‐order Møller–Plesset (SCS‐MP2) theory. Initial propositions for various structures of the BA3and B2A2aggregates are generated with model potentials based on density functional theory combined with the symmetry‐adapted perturbation theory (DFT‐SAPT) approach. Shape and relative cluster stabilities are then confirmed with SCS‐MP2. T‐shaped geometries are the dominant structural motifs. Higher‐energy isomers are also observed. The detected cluster structures are correlated with possible cluster formation pathways and their role as crystallization seeds is discussed.
IR Spectroscopy of the 4‐Aminobenzonitrile–Ar Cluster in the S0, S1 Neutral and D0 Cationic States
Authors: Nakamura Takashi , Miyazaki Mitsuhiko , Ishiuchi Shun‐ichi , Weiler Martin , Schmies Matthias , Dopfer Otto , Fujii Masaaki 
Published: November 2012

AbstractThe S1–S0 resonant enhanced multiphoton ionization (REMPI) spectrum as well as the infrared (IR) spectra in the S0 and S1 states of 4‐aminobenzonitrile (4ABN) and its van der Waals complex with Ar (4ABN–Ar) were measured by means of IR depletion spectroscopy (REMPI–IR). The IR spectrum of 4ABN–Ar in S0 shows symmetric and antisymmetric NH stretching vibrations (νs and νa) of the amino group at the same positions as those in the 4ABN monomer. This suggests that the Ar ligand locates above the benzene ring by van der Waals interactions (π‐bound). The same coincidence of vibrational frequencies was found in S1, and the π‐bound geometry was kept by the electronic excitation. The REMPI–IR spectrum of 4ABN+–Ar was also measured, and three major vibrational transitions were found. From the comparison to the IR dissociation spectrum with an electron impact source (EI–IR), they were assigned to νs, νa and an NH‐bending overtone of the π‐bound structure. It is concluded that photoionization of 4ABN+–Ar does not promote site‐switching of Ar from the π‐site to the H‐site.
Mesenchymal markers on human adipose stem/progenitor cells
Authors: Zimmerlin Ludovic , Donnenberg Vera S. , Rubin J. Peter , Donnenberg Albert D. 
Published: November 2012

AbstractThe stromal‐vascular fraction (SVF) of adipose tissue is a rich source of multipotent stem cells. We and others have described three major populations of stem/progenitor cells in this fraction, all closely associated with small blood vessels: endothelial progenitor cells (EPC, CD45−/CD31+/CD34+), pericytes (CD45−/CD31−/CD146+), and supra‐adventitial adipose stromal cells (SA‐ASC, CD45−/CD31−/CD146−/CD34+). EPC are luminal, pericytes are adventitial, and SA‐ASC surround the vessel like a sheath. The multipotency of the pericytes and SA‐ASC compartments is strikingly similar to that of CD45−/CD34−/CD73+/CD105+/CD90+ bone marrow‐derived mesenchymal stem cells (BM‐MSC). Here, we determine the extent to which this mesenchymal pattern is expressed on the three adipose stem/progenitor populations. Eight independent adipose tissue samples were analyzed in a single tube (CD105‐FITC/CD73‐PE/CD146‐PETXR/CD14‐PECY5/CD33‐PECY5/CD235A‐PECY5/CD31‐PECY7/CD90‐APC/CD34‐A700/CD45‐APCCY7/DAPI). Adipose EPC were highly proliferative with (14.3 ± 2.8)% (mean ± SEM) having >2N DNA. About half (53.1 ± 7.6)% coexpressed CD73 and CD105, and (71.9 ± 7.4)% expressed CD90. Pericytes were less proliferative [(8.2 ± 3.4)% >2N DNA)] with a smaller proportion [(29.6 ± 6.9)% CD73+/CD105+, (60.5 ± 10.2)% CD90+] expressing mesenchymal associated markers. However, the CD34+ subset of CD146+ pericytes were both highly proliferative [(15.1 ± 3.6)% with >2N DNA] and of uniform mesenchymal phenotype [(93.3 ± 3.7)% CD73+/CD105+, (97.8 ± 0.7)% CD90+], suggesting transit amplifying progenitor cells. SA‐ASC were the least proliferative [(3.7 ± 0.8)%>2N DNA] but were also highly mesenchymal in phenotype [(94.4 ± 3.2)% CD73+/CD105+, (95.5 ± 1.2)% CD90+]. These data imply a progenitor/progeny relationship between pericytes and SA‐ASC, the most mesenchymal of SVF cells. Despite phenotypic and functional similarities to BM‐MSC, SA‐ASC are distinguished by CD34 expression. © 2012 International Society for Advancement of Cytometry
Diastereodivergent Synthesis of Chiral vic‐Disubstituted‐Cyclobutane Scaffolds: 1,3‐Amino Alcohol and 1,3‐Diamine Derivatives – Preliminary Use in Organocatalysis
Authors: Mayans Enric , Gargallo Albert , Álvarez‐Larena Ángel , Illa Ona , Ortuño Rosa M. 
Published: November 2012

AbstractThe synthesis of chiral cyclobutane containing 1,3‐amino alcohols and 1,3‐diamines has been accomplished in an efficient and diastereodivergent manner from a common chiral precursor. Regioselective manipulation of functional groups in the prepared products provides an easy entry to several derivatives, such as thioureas. Preliminary results on the use of these compounds as bifunctional organocatalysts are reported.
Effect of the Dispersing Agent on the Electrochemical Response of Glassy Carbon Electrodes Modified with Dispersions of Carbon Nanotubes
Authors: González‐Segura Karina , Cañete‐Rosales Paulina , del Rio Rodrigo , Yáñez Claudia , Ferreyra Nancy F. , Rivas Gustavo A. , Bollo Soledad 
Published: November 2012

AbstractThe electrochemical response of a glassy carbon electrode modified with carbon nanotubes (CNT) dispersed in two solvents, water and DMF, and two polymers, chitosan and Nafion is reported. The films were homogeneous when the dispersing agent was water or DMF. In the case of polymers, the surfaces present areas with different density of CNTs. A more sensitive electrochemical response was obtained when CNTs are dispersed in the solvents. In the case of CNT dispersed with polymers, the nature of the polymer demonstrated to be a critical parameter not only for dispersing the nanotubes but also for the electrochemical activity of the resulting electrodes.
Runoff and erosion processes and rates in the Zin valley badlands, northern Negev, Israel
Authors: Yair A. , Lavee H. , Bryan R. B. , Adar E. 
Published: November 2012

AbstractBadland areas are usually regarded as impermeable zones which generate high runoff and are very vulnerable to sheetwash and rainsplash. To test those considerations sprinkling experiments using two rainfall simulators were carried out on slopes of varying aspect in the northern Negev (Israel). For one unit 1·5 m2 plots were used with rainfall of natural characteristics at 36 mm/hr intensity and 43–48 minute duration, runoff being recorded and water/sediment samples taken every 5 minutes. The second unit was used on 30–50 m2 plots but rainfall energy production was below that of natural rainfall. Results show that due to the high stability and strong flocculation of clay‐rich aggregates rainsplash is ineffective in surface sealing so that infiltration capacities remain high despite intense, prolonged rainfall. Aspect differences are reflected in variation of surface properties despite homogenous bed‐rock, which cause marked differences in hydrological response. North‐facing slopes respond more quickly, more frequently and produce more runoff than south‐facing slopes. Non‐uniform runoff generation is also seen within plots of one aspect reflecting subtle variations in surface properties. Comparison of rainfall intensity and duration used during the experiments with those prevailing under natural conditions shows that under present day conditions surface flow in the Zin valley badlands must be extremely infrequent and denudation rates very low.
Erosion and deposition by debris flows at Mt Thomas, North Canterbury, New Zealand
Authors: Pierson Thomas C. 
Published: November 2012

AbstractThe grass‐covered slopes on the southern flank of Mt Thomas, an upfaulted block of highly sheared sandstone and argillite 40 km NW of Christchurch, New Zealand, are presently undergoing severe erosion by a combination of mass‐wasting processes. Gully erosion, soil slips, and debris flows have carved out a number of steep, deeply incised ravines, from which coarse debris is transported (primarily by debris flows) to alluvial fans below. Geologic and historical evidence indicates that debris flows have been episodically active here for at least the last 20,000 years and have been the dominant process in fan building. This demonstrates that catastrophic geomorphic processes, rather than processes acting at relatively uniform rates, can be dominant in humid‐temperate areas as well as in arid and semi‐arid regions.In April 1978, debris flows were triggered in one of two unstable ravines in the Bullock Creek catchment by a moderate intensity, long duration rainstorm with a return period in excess of 20 years. Surges of fluid debris, moving at velocities up to 5 m/s, transported a dense slurry of gravel, sand, and mud up to 3·5 km over a vertical fall of 600 m. Deposition on the alluvial fan occurred when the flows left the confines of an entrenched fan‐head channel and spread out as a 0·16 km2 sheet averaging 1·2 m thick. In all, 195,000 m3 were deposited, roughly a third of that being reworked sediments from the head of the fan. Sediment yield from this one event would be equivalent to several thousand years worth of erosion at average sediment discharge rates for small South Island mountain catchments.Samples of viscous fluid debris during surges contained up to 84 per cent solids, composed of 70 per cent gravel, 20 per cent silt, and 4 per cent clay. Fluid density of the material ranged between 1·95 and 2·13 g/cm3, and it was extremely poorly sorted. Between surges the fluid was less viscous, less dense, and unable to carry gravel in suspension. Severe fan‐head entrenchment of the stream channel (approximately 10 m in less than 24 hours) was accomplished by the erosive action of the surges.Tectonic uplift of the Mt Thomas block and the weak, crushed condition of the bedrock appear to be ultimately responsible for the catastropic erosion of slopes in the Bullock Creek catchment. However, forest clearing within the last few centuries appears to have greatly increased the rate of mass wasting and gully erosion on these slopes.
The erosion of drainage ditches and its effect on bed‐load yields in mid‐Wales: Reconnaissance case studies
Authors: Newson Malcolm 
Published: November 2012

AbstractOpen ditching is a common and relatively cheap way of providing drainage for wet upland soils prior to afforestation or improved agriculture; it is sometimes also used to channelize moorland runoff into water storage schemes. In contrast to piped under‐drainage there is considerable danger of erosion in open ditches. Results are reported of investigations into the yield of bed‐load from ditched catchments; compared with unditched catchments there is a considerable increase in yield and this causes costly local problems of sedimentation. However, the implications of the erosion for downstream channel changes and reservoir sedimentation in the uplands are harder to predict without further study of the storage processes affecting bed‐load and of the influence of flood flows. The case studies are used to point to improvements in the design of open drainage networks.
Floodplain inundation: Processes and relationships with channel discharge
Authors: Hughes D. A. 
Published: November 2012

AbstractThe factors affecting the relationship between channel discharge and volume of inundation are discussed. For many floodplains this relationship is not simple, but involves hysteretic effects which vary according to the hydrological characteristics of individual floods and the way in which these interact with the surface form of the floodplain reach. Some methods of deriving or estimating the extent of the hysteresis on floodplain reaches are suggested, although an acute lack of available data prevents detailed examination at present. Further investigations are required before floodplain conductivity relations can be used as an aid to flood routing procedures or in floodplain management problems. A major priority must be the acquisition of sequential inundation data.
Distributed and boundary model predictive control for the heat equation
Authors: Altmüller Nils , Grüne Lars 
Published: November 2012

AbstractWe consider a model predictive control (MPC) scheme without stabilizing terminal constraints applied to the linear heat equation. We apply a method to analyze minimal stabilizing optimization horizons based on an exponential controllability condition. While the method is known to yield conservative quantitative results for concrete examples, our analysis shows that it precisely determines qualitative changes in the horizon for changing parameters and changing problem structures. Particularly, it is able to explain numerically observed differences in the stability behavior of MPC for distributed and for boundary control (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal control of coupled multiphysics problems: Guidelines for real‐life applications demonstrated for a complex fuel cell model
Authors: Rund Armin , Chudej Kurt , Kerler Johanna , Pesch Hans Josef , Sternberg Kati 
Published: November 2012

AbstractIn practice one often is confronted with the simulation and optimization of dynamical processes of multiphysics systems depending on time and space. This paper shall serve as a guidebook for practioneers who wants to proceed from simulation to optimization. We are specially concerned in this paper with optimal control problems involving partial differential equations. After providing an insight into the theory of optimal control problems with partial differential equations, the focus of the paper lies on their numerical treatment to obtain approximate optimal solutions, or more precisely approximate candidate optimal solutions. The two basic approaches, first optimize then discretize (FOTD) and first discretize then optimize (FDTO) are first described in an abstract setting and then evaluated by means of the fuel cell example of this paper which can serve as a prototype problem for multiphysics processes. The example describes the dynamical behaviour inside a certain type of high temperature fuel cell where gas flows, heat distribution, and potential fields as well as chemical reactions are modelled by hyperbolic and parabolic partial differential as well as ordinary differential algebraic equations. The underlying problem is an optimal control problem where up to 28 instationary partial differential algebraic equations in one, respectively two spatial dimensions are involved. In the conclusion pros and cons of the aforementioned approaches are discussed. Hereby, not only the numerical efficiency but also the investigation of human resources are balanced against each other (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Adaptive refinement based on asymptotic expansions of finite element solutions for node insertion in 1d
Authors: Friederich Jan , Leugering Günther , Steinmann Paul 
Published: November 2012

AbstractWe consider refinement of finite element discretizations by splitting nodes along edges. For this process, we derive asymptotic expansions of Galerkin solutions of linear second‐order elliptic equations. Thereby, we calculate a topological derivative w.r.t. node insertion for functionals such as the total potential energy, minimization of which decreases the approximation error in the energy norm. Hence, these sensitivities can be used to define indicators for local h ‐refinement. Our results suggest that this procedure leads to an efficient adaptive refinement method. This presentation is concerned with a model problem in 1d. The extension of this concept to higher dimensions will be the subject of forthcoming publications (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Regularized nonlinear scalarization for vector optimization problems with PDE‐constraints
Authors: Leugering G. , Schiel R. 
Published: November 2012

AbstractThis paper concerns the generalization and regularization of a nonlinear scalarization method by Pascoletti and Serafini, [14], to abstract partially ordered Banach spaces. In particular, we put emphasis on the possibility that the ordering cone might have an empty interior. All this is motivated by applying the method to a vector optimization problem with PDE‐constraints (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Multi‐Locus Likelihood Method for Assessing Parent‐of‐Origin Effects Using Case‐Control Mother‐Child Pairs
Authors: Lin Dongyu , Weinberg Clarice R. , Feng Rui , Hochner Hagit , Chen Jinbo 
Published: November 2012

ABSTRACTParent‐of‐origin effects have been pointed out to be one plausible source of the heritability that was unexplained by genome‐wide association studies. Here, we consider a case‐control mother‐child pair design for studying parent‐of‐origin effects of offspring genes on neonatal/early‐life disorders or pregnancy‐related conditions. In contrast to the standard case‐control design, the case‐control mother‐child pair design contains valuable parental information and therefore permits powerful assessment of parent‐of‐origin effects. Suppose the region under study is in Hardy‐Weinberg equilibrium, inheritance is Mendelian at the diallelic locus under study, there is random mating in the source population, and the SNP under study is not related to risk for the phenotype under study because of linkage disequilibrium (LD) with other SNPs. Using a maximum likelihood method that simultaneously assesses likely parental sources and estimates effect sizes of the two offspring genotypes, we investigate the extent of power increase for testing parent‐of‐origin effects through the incorporation of genotype data for adjacent markers that are in LD with the test locus. Our method does not need to assume the outcome is rare because it exploits supplementary information on phenotype prevalence. Analysis with simulated SNP data indicates that incorporating genotype data for adjacent markers greatly help recover the parent‐of‐origin information. This recovery can sometimes substantially improve statistical power for detecting parent‐of‐origin effects. We demonstrate our method by examining parent‐of‐origin effects of the gene PPARGC1A on low birth weight using data from 636 mother‐child pairs in the Jerusalem Perinatal Study.