bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scheibe‐Aggregate Monolayers of Cyanine Dyes without Long Alkyl Chains
Authors: Yonezawa Y. , Möbius D. , Kuhn H. 
Published: July 2012

AbstractScheibe‐aggregates of three cyanine dyes with methyl or ethyl groups instead of long alkyl substituents have been prepared at the air‐water interface by spreading a mixture of the cyanine dye and arachidic acid on a water surface and compressing the monolayer. The general features of the reflection spectra of the dye‐arachidic acid monolayers at the air‐water interface, in particular the presence of a distinct J‐band, are in accordance with absorption spectra of monolayers deposited on glass plates by the Langmuir‐Blodgett technique. The dichroism observed in polarized absorption spectra of the dye‐arachidic acid films indicates that the Scheibe‐aggregates of the dyes with a meso phenyl group have a preferential orientation of the long axis of the molecules in the layer plane parallel to the direction of motion in depositing the layer. The brick‐stone model of Scheibe‐aggregates is adequate for chromophore organization in these monolayers.
A Comment on the β‐Factor and Enthalpy of Activation for Oxygen Reduction at Pt and Au Electrodes
Authors: Damjanovic A. , Sepa D. B. , Vracar Lj. M. , Vojnovic M. V. 
Published: July 2012

AbstractTemperature dependence of the symmetry factor, β, for oxygen reduction at Au electrodes is found to be different than that at Pt electrodes under similar experimental conditions. At Au electrodes, β is proportional to absolute temperature, i.e., β = β'T, while at Pt electrodes β is independent of T. The significance of apparent enthalpies of activation at these electrodes, ΔH*ap, determined at a constant potential E, is reassessed in view of the different dependences of β on T. At Au, Δ*ap is equal to Δ*0, the enthalpy of activation at the zero Galvani potential difference at the electrode. It is therefore independent of the potential at which the change of current density with T has been determined. At Pt, ΔH*ap is the enthalpy corresponding to the potential at which the change of current density with T has been determined. It increases linearly with electrode potential.
Röntgenstrukturuntersuchung des flüssigen Silicium‐, Germanium‐ und Zinntetrachlorids. Ein Beitrag zur Frage einer gemeinsamen Flüssigkeitsstruktur. II. Bestimmung der individuellen partiellen Paarkorrelationsfunktionen. Vorschlag eines einheitlichen Strukturmodells
Authors: Jöllenbeck K. M. , Weidner J. U. 
Published: July 2012

AbstractThe determination of partial atomic pair correlation functions for liquid tetrachlorides following the method of isomorphic chemical substitution in X‐ray scattering, is reported. From the properties of the intensity distributions of radiation scattered by silicon‐, germanium‐, and tin tetrachloride and binary liquid mixtures, which were investigated recently, there is evidence for the individual partial functions to differ gradually when changing the components or the mole fraction of the mixtures. For separating the partials from the intermolecular reduced intensities, a procedure of successive refinement was employed, therefore, that accounts for such differences, and allows for the realization of well‐known restrictions reflecting, for example, the limiting behaviour of the pair correlation functions with respect to small and large intermolecular atomic distances, and the preservation of particle numbers. Using functions that are parametrized adequately, the procedure enables the individual partial pair correlation functions of pure compounds SiCl4, GeCL4, SnCl4, to be deduced.—By analysis of the partial correlation functions and partial particle numbers conclusions are drawn concerning the structure of short range order that amount to a definite suggestion for a structural model. Accordingly, short range order is represented by a space filling configuration common to the tetrachloride liquids under consideration, but exposing gradually different features, which is derived from a structural model for liquid CCl4 proposed by Narten.
Extraction of nickel with dihexyl phosphinic acid and study of Ni(II)‐saccharate complexes
Authors: Beneitez P. , Millan A. 
Published: July 2012

AbstractThe equilibrium extraction behavior for nickel(II) using a kerosene (Shellsol‐T) solution containing dihexyl‐phosphinic acid is studied. From experimental data, treated by a graphical method, monomeric Ni(DHP)2(HDHP)2 and dimeric (Ni(DHP)2(HDHP)2)2 species are found responsible for the extraction. Constants for the extraction equilibrium have been determined as: log K12 = −11.45 and log K22 = −18.81. Constant for monomer‐dimer equilibrium of nickel species is given as: log K = 4.10. —In presence of ligand, saccharate, is concluded to exist in the aqueous phase a nickel(II)‐saccharate complex (1:1) with a stability constant of 3.46 · 103 and general formula C6H8O8Ni · 3H2O.
The use of high UV photon densities for physicochemical studies in the life sciences
Authors: Greulich K. O. , Wolfrum J. 
Published: July 2012

AbstractHigh UV photon densities can be used in a wide range of applications in life sciences. Below the threshold for photodamage, time resolved fluorescence spectroscopy and UV resonance Raman Spectroscopy with proteins and nucleic acids can be performed. 1 GW/cm2 is significantly above the ablation threshold of tissue and can now be transported conveniently through tapered quartz fibres. 100 GW/cm2 in the tunable wavelength region 265 to 685 nm are generated by coupling nearly diffraction limited dye laser pulses into a microscope. This allows a detailed wavelength study on the interaction of high photon densities with human red blood cells, which may serve as a model for biological tissue. Using the same equipment, biological cells can be fused with each other in a very selective way. Furthermore, human chromosomes can be microdissected into fine slices and DNA for diagnosis of human disease can be isolated from these localized regions of the human genome.
Search of “chlorophyll forms” in vivo by non‐linear laser spectroscopy
Authors: Leupold D. , Stiel H. , Klose E. , Hoffmann P. 
Published: July 2012

AbstractInduction of a non‐linearity in the long‐wavelength part of the S0 —S1 absorption band of chlorophyll in vivo by a monochromatic pulse results in a simultaneous band shape change in the whole range of investigation (645 – 680 nm). Such homogeneous broadening behaviour at least for time periods ⩾0.5 ns (pulse duration) does not support the hypothesis of many small sub‐bands representing “chlorophyll forms”. The band shape changes at different excitation intensities indicate two excited state absorptions of antenna chlorophyll.
Laser induced dynamic nuclear polarization
Authors: Hausser K. H. 
Published: July 2012

AbstractA large nuclear spin polarization pn is desirable for most NMR investigations since NMR is basically an insensitive method and since the signal‐to‐noise ratio is proportional to pn. The classical method to polarize nuclear spins is the “solid effect” in which the much higher Boltzmann polarization of unpaired electrons in doublet ground states is transferred to the nuclear spins by inducing forbidden transitions with the selection rules Δms = ±1, Δm1 = ±1. However, a drawback of this method is the presence of unpaired electrons within the sample which produce unwanted effects in most experiments to be performed with polarized nuclear spins. Using the unpaired electronic spins of optically excited triplet states instead of doublet ground states has the important advantage that after switching off the exciting light it renders a diamagnetic crystal with polarized nuclear spins due to the short lifetime of the triplet states. —The population differences of the electronic sublevels of the excited triplet states to be transferred to the nuclear spins originate in this case from the very selective population rates si and depopulation rates ki due to the selection rules of spin orbit coupling. Since the transfer occurs by inducing forbidden transitions by microwaves, the method was termed Microwave Induced Optical Nuclear Polarization (MI —ONP). The different CW‐ and pulse‐techniques are discussed. Furthermore, a more recently developed technique will be described where the polarization is obtained with special cross‐relaxation transitions which satisfy the “Hartmann‐Hahn condition” for electronic spins spin‐locked in the rotating frame to the radio frequency B1‐field and nuclear spins in the static magnetic field B0 in the laboratory frame. —The highest nuclear polarization obtained so far is pn = 33% which corresponds to an amplification factor of more than 2000 as compared to the Boltzmann polarization in the same magnetic field, but we expect to reach even higher polarizations of more than 50% with improved techniques, in particular with higher B1‐fields.
Application of confocal laser scanning microscopy in plant biology
Authors: Knebel W. , Quader H. , Wijnaendts‐van‐Resandt R. , Engelhardt H. 
Published: July 2012

AbstractFluorescence confocal laser scanning microscopy (CLSM) is increasingly acknowledged as a suitable technique to study the 3‐dimensional structure of animal and plant cells. The imaging process involves the collection of the emitted fluorescent light of a defined volume in the object. A powerful processing system is, however, required to store the single data and reconstruct the image of the object. A 3‐D‐image of an object can be achieved either by the extended focus, the stereo image, or the shadowing mode1). —These procedures were applied to elaborate on the spatial arrangement of structural components and organells in fixed or living plant cells. Microtubule arrays in dividing onion root cells and in caulonema tip cells of moss protonemata are visualized by the indirect immunofluorescence technique. In addition, the endoplasmic reticulum is visualized through vital staining with the fluorochrome 3,3'‐dihexyloxacarbocyanine‐iodide (DiOC). For example in adaxial onion bulb scale epidermis cells and root hair cells. Also, several examples are shown which demonstrate the possibilities the CLSM offers with respect to magnification, image, and motility measurements of single organelles. Some of the measurements have been performed with a compact inverted confocal system which also includes a classical fluorescence microscope. Fluorescence confocal laser scanning microscopy turned out to be of great advantage for studying the 3‐D‐arrangement of plant cell constituents due to the property of the focal scanner which discriminates fluorescent light outside of the depth of focus.
Far Infrared Absorption and Rotational Motion of CH3F and of CH3F‐Argon Mixtures at High Pressures to 1000 bar
Authors: Frost M. , Bohn M. A. , Franck E. U. 
Published: July 2012

AbstractFIR‐absorption spectra of methyl fluoride (CH3F) as a pure fluid and as a one mole percent component in mixtures with dense argon and CF4 have been measured. A frequency range between 10 cm‐1 and 200 cm‐1 was covered. Temperatures of —10, 69 and 125°C were used. Total sample pressures extended to 1000 bar. PVT‐data permit the discussion of the spectra as functions of density. Measurements were made with a modified Fourier‐transform IR‐spectrometer. An optical absorption cell for use to 1000 bar and 200°C is described. The molar absorptivity at 69°C has a pronounced maximum at 40 cm‐1 at all temperatures and densities which indicates hindered rotation. This absorption decreases with growing density and an increasing absorption develops above 70 cm‐1, caused by in termolecular libration. The suppression of the CH3F‐rotation in the dense argon is much weaker than in the pure polar fluid. The intermolecular mean squared torque increases linearly with density with the pure fluids CH3F and CHFl2F and about four times as strongly as with the compounds diluted in argon. Spectral fourth moments of the power spectra and time correlation functions for pure fluids and mixtures are compared to show the influence of dipole interaction on rotation and libration. Spectra obtained with CH3F in high pressure CF4 are analogous to those with argon as solvent.
Effects of oxygen‐glucose deprivation on microglial mobility and viability in developing mouse hippocampal tissues
Authors: Eyo Ukpong , Dailey Michael E. 
Published: July 2012

AbstractAs brain‐resident immune cells, microglia (MG) survey the brain parenchyma to maintain homeostasis during development and following injury. Research in perinatal stroke, a leading cause of lifelong disability, has implicated MG as targets for therapeutic intervention during stroke. Although MG responses are complex, work in developing rodents suggests that MG limit brain damage after stroke. However, little is known about how energy‐limiting conditions affect MG survival and mobility (motility and migration) in developing brain tissues. Here, we used confocal time‐lapse imaging to monitor MG viability and mobility during hypoxia or oxygen‐glucose deprivation (OGD) in hippocampal tissue slices derived from neonatal GFP‐reporter mice (CX3CR1GFP/+). We found that MG remain viable for at least 6 h of hypoxia but begin to die after 2 h of OGD, while both hypoxia and OGD reduce MG motility. Unexpectedly, some MG retain or recover motility during OGD and can engulf dead cells. Additionally, MG from younger neonates (P2–P3) are more resistant to OGD than those from older ones (P6–P7), indicating increasing vulnerability with developmental age. Finally, transient (2 h) OGD also increases MG death, and although motility is rapidly restored after transient OGD, it remains below control levels for many hours. Together, these results show that MG in neonatal mouse brain tissues are vulnerable to both transient and sustained OGD, and many MG die within hours after onset of OGD. Preventing MG death may, therefore, provide a strategy for promoting tissue restoration after stroke. © 2012 Wiley Periodicals, Inc.
Roles of cytokines and progesterone in the regulation of the nitric oxide generating system in bovine luteal endothelial cells
Authors: Yoshioka Shin , Acosta Tomas J. , Okuda Kiyoshi 
Published: July 2012

AbstractNitric oxide (NO) produced by luteal endothelial cells (LECs) plays important roles in regulating corpus luteum (CL) function, yet the local mechanism regulating NO generation in bovine CL remains unclear. The purpose of the present study was to elucidate if tumor necrosis factor‐α (TNF), interferon γ (IFNG), and/or progesterone (P4) play roles in regulating NO generating system in LECs. Cultured bovine LECs obtained from the CL at the mid‐luteal stage (Days 8–12 of the cycle) were treated for 24 hr with TNF (2.9 nM), IFNG (2.5 nM), or P4 (0.032–32 µM). NO production was increased by TNF and IFNG, but decreased by P4 (P < 0.05). TNF and IFNG stimulated the relative steady‐state amounts of inducible nitric oxide synthase (iNOS) mRNA and iNOS protein expression (P < 0.05), whereas P4 inhibited relative steady‐state amounts of iNOS mRNA and iNOS protein expression (P < 0.05). In contrast, endothelial nitric oxide synthase (eNOS) expression was not affected by any treatment. TNF and IFNG stimulated NOS activity (P < 0.05) and 1400W, a specific inhibitor of iNOS, reduced NO production stimulated by TNF and IFNG in LECs (P < 0.05). Onapristone, a specific P4 receptor antagonist, blocked the inhibitory effect of P4 on NO production in LECs (P < 0.05). The overall findings suggest that TNF and IFNG accelerate luteolysis by increasing NO production via stimulation of iNOS expression and NOS activity in bovine LECs. P4, on the other hand, may act in maintaining CL function by suppressing iNOS expression in bovine LECs. Mol. Reprod. Dev. 79: 689–696, 2012. © 2012 Wiley Periodicals, Inc.
All‐electron scalar relativistic calculations of atomic hydrogen adsorption on cubo‐octahedron Pt55 nanoparticles
Authors: Shin Jungho , Choi Jung‐Hae , Lee Seung‐Cheol 
Published: July 2012

AbstractAdsorption energies of hydrogen atoms on Pt were investigated by all‐electron density functional calculations using numeric atom‐centered orbital basis sets. The all‐electron calculations gave lower predicted adsorption energies for hydrogen atoms than pseudopotential calculations. Size effects were considered by comparing adsorption on bulk surfaces and nanoparticles. How size affects catalytic activity is presented on volcano curves, which can give insights into the catalytic activities of practical nanocatalysts.
A Novel Technique for Conduction Studies of the Infrapatellar Nerve
Authors: Tsenter Jeanna , Schwartz Isabella , Katz‐Leurer Michal , Meiner Zeev , Goldin Diana , Vatine Jean‐Jacques 
Published: July 2012

ObjectiveTo introduce a noninvasive method for electrodiagnostic evaluation of the infrapatellar nerve (IPN).DesignA prospective cohort study.SettingElectrodiagnostic laboratory, rehabilitation department, Hadassah University Hospital.ParticipantsA total of 38 healthy adults; 57 asymptomatic limbs were studied.MethodsSensory nerve action potential of the IPN was recorded with surface electrodes placed 2.5 cm below the distal pole of the patella and 2 cm medially from the medial border of the patellar tendon. Transcutaneous antidromic electrical stimulation of IPN was applied above the medial femoral condyle and 8‐10 cm proximally from the active surface electrode.ResultsThe sensory nerve action potential mean (n = 38) onset latency was 1.69 ± 0.32 ms. Peak latency was 2.36 ± 0.47 ms, and amplitude was 6.96 ± 3.68 μV.ConclusionsThis article describes a novel and simple technique for IPN conduction electrodiagnostic examination. The method used provides a new tool to evaluate IPN injury in reference to anterior or inferior knee pain with associated sensory deficit.
Late-Quaternary vegetational history of the Inner Hebrides
Authors: Birks H. J. B. , Williams W. 
Published: July 2012

SynopsisThe Inner Hebrides support a diverse flora and a wide range of vegetation types today. Native woodland is rare, even on the larger islands of Skye and Mull. The present-day floristic and vegetational diversity and the scarcity of native woodland raise important ecological questions, answers to which can be provided by pollen analysis of loch or bog sediments.Pollen analysis of sediments deposited during the last glacial stage on Skye and on Lewis suggest that some plants may have survived the last glaciation within the Hebrides. Pollen analysis of late-glacial (13500–10000 years ago) sediments on Skye indicate that even at the close of the last glaciation there was considerable floristic and vegetational diversity related to geology, altitude, and climate.Post-glacial (10000–0 year ago) vegetational histories are available from Skye, Soay, Canna, Tiree, and Jura. Forest was rare or absent on Canna and Tiree as well as on the Outer Hebrides throughout the postglacial. In contrast Soay and southern and eastern Skye were well forested, with birch, alder, hazel, and small amounts of elm and oak. Pine was confined to eastern Skye. Since 5,000 years ago there has been extensive forest destruction by man, especially on the better soils, and the spread of bog and heath on the poorer soils. Northern Skye supported birch, hazel, and willow scrub during the post-glacial. This has largely been removed by man since about 5,000 years ago. The present-day vegetation of the Inner Hebrides is predominantly anthropogenic.
Lichens of Colonsay
Authors: Rose Francis , Coppins Brian J. 
Published: July 2012

SynopsisThe results of eight days' recording and collecting of lichens on the island of Colonsay are presented. A wide range of habitats were studied but particular attention was paid to the two relict oak-woodlands and some areas of calcareous machair. An impressive total of 342 lichen taxa was recorded, and two species were added to the British flora.
Shellfish resources in the Inner Hebrides
Authors: Mason James , Shelton R. G. J. , Drinkwater J. , Howard F. G. 
Published: July 2012

SynopsisShellfish fishing, traditionally associated with crofting areas, has expanded greatly in Scotland generally, and particularly in the Inner Hebrides, during the past 30 years. Landings from Inner Hebrides waters in 1979 were valued at about £11 millions. Processing factories and storage installations have facilitated marketing.The seas around the Inner Hebrides provide a wide variety of habitats, from the fine mud necessary for Norway lobsters, through the sandy gravel on which scallops live, to the rocky sea bed inhabited by lobsters.The most valuable fisheries, those for Norway lobsters and scallops, are post-war developments. In both, the stocks appear to be in a healthy state. Landings in the traditional lobster fishery have declined recently and the stocks are giving some cause for concern. Periwinkles and queens make useful contributions to the economy. Pink shrimps and squat lobsters, though not sufficiently abundant to support a directed fishery, form a useful, occasional by-catch. Squids are caught sporadically, but their availability is very variable. The crab stocks could stand much greater exploitation.
Comparisons of Precision and Bias with Two Age Interpretation Techniques for Opercular Bones of Longnose Sucker, a Long-Lived Northern Fish
Authors: Perry Robert C. , Casselman John M. 
Published: July 2012

Abstract
Two preparations of opercular bones for estimating age of longnose suckers Catastomus catastomus revealed that annuli were obscured by dense bone and undetected when the whole operculum technique was used. By thin-sectioning the opercula, we removed the dense bone, revealing previously obscured annuli. Using opercula collected from older fish in Labrador, Canada, we found that the dense bone overgrowth led to an overall age bias of 1 year. When samples were broken into groups based on sectioned ages, however, there were minimal differences in age between the two techniques for fish age 6 and younger and a 2-year age difference for fish estimated to be age 10 and older. To compare precision in locating annuli between the two techniques, we calculated coefficient of variation values among independent determinations. Both techniques demonstrated low variance, however, age determinations had greater variation with thin-sectioning than with whole opercula interpretations. Therefore, we conclude that care must be taken when making annulus determinations from thin-sectioning. Due to the presence of dense bone overgrowth, associated with the whole operculum technique, we conclude a combination of both techniques would provide the most thorough procedure for interpreting opercular age for such long-lived fish (30–50 years).
Received November 23, 2011; accepted April 5, 2012
Mayo Clinic Challenging Images for Pulmonary Board Review
Authors: Rosenow, III Edward C. 
Published: July 2012

Abstract
This resource features a collection of more than 150 very unusual intrathoracic conditions that every pulmonologist, thoracic surgeon, and chest radiologist should know and understand. Featuring a broad array of chest images and corresponding pearls of wisdom on how to best interpret the chest radiograph and other images that are reviewed primarily by pulmonologists, thoracic surgeons, radiologists, and pathologists, the conditions are presented in a didactic, user-friendly, and interactive tutorial format to help practitioners recognize these conditions when encountered in practice.