bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of recording performances between three different stabilizing schemes of soft underlayer
Authors: Lee Hwan‐Soo , Hong Sooyoul , Lee Hyung J.
Published: December 2007

Recording characteristics of perpendicular recording media with three different stabilizing schemes of soft under (SUL) were investigated; conventional, synthetic antiparallelly (SAP) coupled, and antiferromagnetically (AFM) coupled SULs. The strong pinning due to the AFM, which led to a quasi‐single domain, presented some negative effects on recording performances, displaying a poorer writing characteristic and a stronger sensitivity to adjacent dc‐saturated tracks. Even multi‐domains due to the relatively weak pinning of the SAP appear to be sufficient for suppressing additional media noise from the SUL as the domain structure is properly controlled. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The property of multilayered SmCo5 film with perpendicular magnetic anisotropy
Authors: Takei Shigeto , Liu Xiaoxi , Morisako Akimitsu
Published: December 2007

In order to fabricate thick SmCo5 film, the dependences of the magnetic properties of SmCo/Ru/Cu/Ru films and its multilayer films on the SmCo layer thickness were studied. The SmCo/Ru/Cu/Ru film with the SmCo layer thickness up to 200 nm showed the perpendicular magnetic anisotropy while the multilayer film with the total SmCo layer thickness of 1000 nm indicated the magnetic easy axis was in the perpendicular direction. It was found that the multilayered structure is preferable for the increase in total thickness of the SmCo layer with the perpendicular anisotropy. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Detection of current‐driven magnetic domain wall deformation using anisotropic magnetoresistance effect
Authors: Maekawa H. , Nozaki T. , Kasai S. , Mizuguchi M. , Shiraishi M. , Ono T. , Suzuki Y.
Published: December 2007

We report on an electrical detection of current driven domain wall (DW) deformation induced by a current pulse injection in arc‐shaped permalloy (Py) submicron wires. Current polarity and pulse length dependence were investigated under an assisting external magnetic field. Initial DW states prepared by an application of a large magnetic field were distributed to two distinct DW states. A current pulse application promoted transition between them. In addition, the third DW state was established only by an application of the short pulses (<50 ns). This result suggests the possibility of the high‐speed control of the DW dynamics. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
PMMA coated carbonyl iron microbeads and their magnetic characteristics
Authors: Kim Min Su , Cho Min Sung , Choi Hyoung Jin
Published: December 2007

In order to improve the stability of magnetorheological (MR) fluid, we synthesized poly(methyl methacrylate) (PMMA) ‐ encapsulated carbonyl iron (CI) particles by an in‐situ dispersion polymerization method. In addition, PMMA shell was cross‐linked by a cross‐linking agent. The cross‐linked PMMA is expected to be more effective than non‐cross‐linked PMMA, improving the physical properties. The synthesized CIPMMA composite particles were characterized by SEM, and VSM. Cross‐linking of PMMA was also confirmed by measuring the FT‐IR after etching process. Rheological properties of the PMMA‐coated CI based MR fluid were measured via a rotational rheometer. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin‐filtering effect in a two‐dimensional electron gas under a local fringe field
Authors: Huh Seon‐Gu , Eom Jonghwa , Koo Hyun Cheol , Kim Hyung‐jun , Chang Joonyeon , Han Suk‐Hee
Published: December 2007

We fabricated a spin‐filtering device which consists of InAs based two‐dimensional electron gas and two ferromagnetic pads. A fringe field at the edge of a ferromagnetic pad was used to induce spin polarization of the moving electrons in a two‐dimensional electron gas. The direction of the fringe field was determined by the magnetization of the ferromagnetic pad, which was switched by using the external magnetic field. A current of which spins were aligned by one fringe field (polarizer) was filtered by the other fringe field (analyzer). The resistance of the device was in either a high state or a low state depending on the alignment of the fringe fields. The spin‐filtering effect diminishes rapidly as the thermal energy exceeds the Zeeman splitting. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetometry on quantum Hall systems: Thermodynamic energy gaps and the density of states distribution
Authors: Wilde M. A. , Springborn J. I. , Roesler O. , Ruhe N. , Schwarz M. P. , Heitmann D. , Grundler D.
Published: December 2007

We review experiments on the de Haas–van Alphen (dHvA) effect, i.e., the quantum oscillatory behavior of the magnetization M, in modulation‐doped AlGaAs/GaAs heterostructures at low temperature T. In particular we focus on the thermodynamic energy gaps and the density of states (DOS) of two‐dimensional electron systems (2DES's) in the integer quantum Hall regime. M as a thermodynamic quantity yields direct access to both quantities. Energy gaps due to Landau quantization at even integer filling factors ν are extracted from different samples that cover a wide range of electronic parameters. They are varied by heterostructure growth parameters. For the quantitative analysis we simulate the magnetization starting from a single‐particle model DOS. We find that a DOS consisting of, both, levels with a Gaussian broadening and a background that increases linearly with ν is essential to model magnetization data for the different heterostructures over a wide range of ns and T. In particular we discuss the correlation of the Landau level broadening with the specific sample parameters. Oscillations in M at odd filling factors resulting from the spin splitting of Landau levels are investigated as a function of magnetic field and electron density ns. We recalculate the exchange‐energy contribution to the spin splitting and find a disagreement with Hartree–Fock calculations. However, our results are consistent with previously published magnetocapacitance measurements. In the sample exhibiting the lowest level broadening we observe discontinuous jumps of M at even ν. This specific feature of the 2DES magnetization was predicted more than 70 years ago by Peierls but never reported for dHvA effect studies before. Both, the significant improvements of the measurement technique and the optimization of heterostructure growth during recent years have allowed us to observe such discontinuities in M. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Weak ferromagnetism in CdMnZnTe single crystal
Authors: Hwang Younghun , Chung Soo‐seong , Um Youngho
Published: December 2007

We studied the magnetic properties of diluted magnetic semiconductors Cd0.65–yMn0.35Zny Te single crystals grown using a vertical Bridgman method. The Cd0.65–yMn0.35Zny Te crystals with various Zn mole fractions have been grown in the zinc‐blende structure. The band‐gap energy obtained from the optical absorption spectrum at 300 K is linearly increased with increasing the addition of Zn into CdMnTe, which may be due to a decrease in the lattice constant. We have observed that the Cd0.22Mn0.35Zn0.43Te crystal showed weak ferromagnetic ordering up to 300 K, and the coercive field was 25 Oe at 250 K. The magnetic moment showed a maximum for the sample with y = 0.43, and the value was approximately ten times larger than that of the Cd0.65Mn0.35Te crystal. This result reflects that Zn ion mediates and enhances the spin‐spin interaction between Mn2+ ions with increasing Zn composition up to y = 0.43. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties of Na0.68CoO2 thin film
Authors: Hsu M. H. , Liu H. L. , Chang W. J. , Lin J. Y.
Published: December 2007

The optical reflectance of single‐crystalline Na0.68CoO2 (thickness around 3000 Å) thin film has been measured over a wide frequency (40–55000 cm–1) and at temperatures between 20 and 300 K. The room‐temperature optical conductivity spectrum displays a metallic character. In addition, one E1u phonon mode at about 518 cm‐1 is identified, while the other four phonon peaks are due to the sapphire substrate. As the temperature is lowered, the Drude plasma frequency exhibits little temperature dependence, whereas the scattering rate monotonically decreases with decreasing temperature. Notably, the Drude scattering rate at 20 K is found to approach zero, consistent with the small residual resistivity, indicating high quality of Na0.68CoO2 thin film. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Permittivity modulation study of multiferroic AlN/NiFe/AlN films
Authors: Hung D. S. , Yao Y. D. , Wu K. T. , Hsu J. C. , Chen Y. C. , Ding Y.
Published: December 2007

This paper reports the dielectric properties of AlN/NiFe/AlN multiferroelectric films that were fabricated by the reactive sputtering system. The permittivity that was relative to thickness and number of NiFe layers was observed from 40 Hz to 30 MHz. In this investigation, we found that the dielectric constant of the AlN/NiFe/AlN/ multilayered film was up to 60 for a nano‐scale NiFe interlayer. The data indicated that the dielectric constant of the AlN/NiFe/AlN was strongly dependent on the number of the NiFe layers but weak to their thickness. The dielectric tuniability of AlN/NiFe/AlN was also observed by in this study. The results concluded the dielectric‐electric variation of AlN films that are modulated by the NiFe ferromagnetic layers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The numerical computation of the self‐demagnetization factor of bonded magnets
Authors: Tu L. T. , Vuong N. V. , Kim C. G.
Published: December 2007

The self‐demagnetization effect (SDE) in bonded magnets (BMs), which are compacted with ferromagnetic particles embedded in a binder medium, was investigated by means of the numerical computation. It is shown that the self‐demagnetization factor N is dependent not only on the shape but also the granular structure of bonded magnets. The calculated factor N is determined as a function of the magnet shape, mass density and particle orientation. And also the influences of the self‐demagnetization effect on the characterization of bonded magnets are discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ru‐mediated interlayer exchange coupling in Co/Pd and Co/Au multilayers with perpendicular magnetic anisotropy
Authors: Kamiko Masao , Chihaya Hiroaki , Yamamoto Ryoichi
Published: December 2007

Ru‐mediated interlayer exchange coupling was introduced in Co/Pd (111) and Co/Au (111) metallic multilayers with perpendicular magnetic anisotropy in order to induce antiferromagnet alignment inside them. The magnetic and electronic transport properties were investigated. The magnetically controlled Co/Pd(111) and Co/Au (111) multilayers exhibited unique resistivity changes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic behaviors and enhanced magnetoresistance in granular (La0. 7Pb0.3MnO3)1−x(Fe2O3)x composites
Authors: Young S. L. , Horng Lance , Ho Y. W. , Wu K. M. , Shih Y. T. , Chen H. Z. , Kao M. C. , Shi J. B. , Lin C. C.
Published: December 2007

Recently, researches indicate that grain boundaries and interfaces can be the major factors of magnetoresistance effects, which has attracted renewed interests on the colossal magnetoresistance materials. In this article, the magnetic behaviours and magnetotransport properties of (La0.7Pb0.3MnO3)1‐x(Fe2O3)x composites have been investigated. Ferromagnetism is gradually suppressed as the weight percentage of Fe2O3 is increased. Saturation magnetization (MS) decreases from 78.7 emu/g for x = 0.0 to 60.6 emu/g for x = 0.2, while ferromagnetic transition temperature (TC) remains around 346K for all composites. The resistivity increases significantly as the x value increases in these composites. It is suggested that the introduction of Fe2O3 into the composites acts as a separation layer between La0.7Pb0.3MnO3 grains. The enhancement of magnetoresistance has been verified with the addition of Fe2O3 into the composites. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characteristics of W‐C‐N thin films on Si as a role of diffusion barrier for La0.67Sr0.33MnO3 manganese oxide layer
Authors: Kim Soo In , Lee Chang Woo
Published: December 2007

W‐C‐N ternary thin films are suggested as a diffusion barrier to prevent the interdiffusion between La0.67Sr0.33MnO3 (La‐Sr‐MnO) and Si substrate for adapting the Si process. La‐Sr‐MnO layers have grown on W‐C‐N/Si thin film by sol‐gel spinning processes and the thermal stabilities of W‐C‐N thin films with various nitrogen concentrations are studied during the annealing process up to 1000 °C. Experimental results show that the grain size of La‐Sr‐MnO layer depends on W‐C‐N diffusion barrier. From these results, the MR ratio of the La‐Sr‐MnO layer on the W‐C‐N films is higher than that of the La‐Sr‐MnO layer on the W‐C films. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Double talk: Synthesizing everyday and science language in the classroom
Authors: Brown Bryan A. , Spang Eliza
Published: December 2007

This research project explores the language practices that emerged as a teacher taught a lesson designed to promote science literacy development for traditionally underrepresented students. This ethnographic study of a Detroit, Michigan, school examined the teacher's use of science language and its influence on students' use of science language. Using sociolinguistic discourse analysis, two modes of classroom language were identified. First, the teacher used a hybrid method of language involving her explaining science ideas by using vernacular and scientific language. This parenthetical type of speech, which we describe as “double talk,” was also found in students. Second, students appropriated this same strategy for using science language in which they produced vernacular and scientific descriptions during explanations. The findings of this study are significant in their contribution to contemporary research about teaching and learning for minority students. These results implicate the need to teach science explicitly as a second language in urban classrooms. © 2007 Wiley Periodicals, Inc. Sci Ed 92:708–732, 2008
Mg2+‐Doped GaN Nanoparticles as Blue‐Light Emitters: A Method to Avoid Sintering at High Temperatures
Authors: Mahalingam Venkataramanan , Sudarsan Vasanthakumaran , Munusamy Prabhakaran , van Veggel Frank C. J. M. , Wang Rui , Steckl Andrew J. , Raudsepp Mati
Published: December 2007

Bright blue‐light emission at 410 nm is observed from Mg2+‐doped GaN nanoparticles prepared by the nitridation of Ga2MgO4 nanoparticles at 950°C. The sintering of these nanoparticles during high‐temperature nitridation was prevented by mixing the Ga2MgO4 precursor nanoparticles with La2O3 as an inert matrix before the nitridation process. The Mg2+‐doped GaN nanoparticles were isolated from the matrix by etching with 10 % nitric acid. The Mg2+‐doped GaN nanoparticles were characterized by photoluminescence, atomic force microscopy, X‐ray diffraction, and IR analyses.
Pharmacological MRI in awake rats predicts selective binding of α4β2 nicotinic receptors
Authors: Chin Chih‐Liang , Pauly James R. , Surber Bruce W. , Skoubis Pamela D. , McGaraughty Steve , Hradil Vincent P. , Luo Yanping , Cox Bryan F. , Fox Gerard B.
Published: December 2007

Neuronal nicotinic receptors are the subject of intensive research focused on developing novel therapies for drug abuse, neurocognitive disorders, neurodegenerative diseases, and pain. In this study, we have applied pharmacological magnetic resonance imaging (phMRI) in awake rats to map functional brain responses to the selective α4β2 nicotinic receptor agonists, A‐85380, and ABT‐594. Moreover, we have validated our methods by comparison with autoradiography using [3H]‐A‐85380 and [3H]‐ABT‐594. Under awake conditions (no anesthesia during scanning) where rats were habituated to the imaging environment, both compounds increased regional cerebral blood volume (rCBV) across multiple brain regions that closely matched regional brain receptor distribution with the same tritiated compounds. In addition, regional ABT‐594‐induced rCBV changes under awake conditions were also derived and characterized using a pharmacological model. Area‐under‐curve and maximum rCBV changes in brain were found to be dose‐related and region‐specific, and corresponded well with the known preclinical behavioral profile of this drug. In contrast, under conditions of α‐chloralose anesthesia where physiological variables were maintained within normal ranges, increases in rCBV induced by ABT‐594 were primarily restricted to some cortical areas and did not agree well with autoradiography data. Our data demonstrate the utility of using phMRI in awake animals to characterize selective pharmacological action but also highlight an important confound (anesthesia) that is rarely considered in preclinical phMRI studies. Synapse 62:159–168, 2008. © 2007 Wiley‐Liss, Inc.
Neurotoxic‐related changes in tyrosine hydroxylase, microglia, myelin, and the blood‐brain barrier in the caudate‐putamen from acute methamphetamine exposure
Authors: Bowyer John F. , Robinson Bonnie , Ali Syed , Schmued Larry C.
Published: December 2007

Changes in the histological morphology of the caudate‐putamen (CPu) were determined after a high‐dose methamphetamine (METH) exposure in an effort to elucidate whether BBB disruption plays a role in CPu neurotoxicity. This was accomplished by evaluating the tyrosine hydroxylase immunoreactivity (TH‐IR), isolectin B4 reactivity, Black Gold II (BG‐II) and Fluoro‐Jade C (FJ‐C) staining, and immunoreactivity to mouse immunoglobulin G (IgG‐IR) in adult male mice at 90‐min, 4‐h, 12‐h, 1‐day, and 3‐day post‐METH exposure. The IgG‐IR indicated that the BBB was only modestly altered in the CPu at time points after neurodegeneration occurred and dependent on hyperthermia and status epilepticus. The modest CPu IgG‐IR changes observed in the perivascular areas indicated that immunoglobulins were present on some CPu microglia 1 day or more after METH. The first signs of CPu damage were swellings in the TH‐IR axons, myelin damage, and a few degenerating neurons at 4‐h post‐METH. The loss of TH‐IR was dependent on hyperthermia but not seizures or CPu neurodegeneration, and the TH‐IR was virtually absent throughout the CPu within 12 h. Surprisingly, signs of FJ‐C labeling (degenerating) axons in the CPu were seen only in the regions of pronounced somatic neurodegeneration and independent of TH‐IR loss. Microglial activation did not occur until 1 day or more post‐METH. In summary, a major BBB disruption within the CPu does not directly contribute to neurotoxicity in this single high‐dose METH exposure. However, seizure activity produced or exacerbated by amygdalar BBB disruption can significantly increase CPu somatic neurodegeneration (but not affect dopamine (DA) terminal damage). The time course of microglial activation indicates a response to the neurodegeneration, myelin damage, and/or damaged DA terminals after loss of TH‐IR. Synapse 62:193–204, 2008. © 2007 Wiley‐Liss, Inc.
Oscillatory firing of dopamine neurons: Differences between cells in the substantia nigra and ventral tegmental area
Authors: Zhang Die , Yang Shen , Jin Guo‐Zhang , Bunney Benjamin S. , Shi Wei‐Xing
Published: December 2007

Neuronal oscillations have been suggested to play an important role in information processing in the brain. Using spectral analysis, we have recently shown that the repetitive burst‐like firing in many dopamine (DA) neurons in the ventral tegmental area (VTA) can be described as a slow oscillation (SO) in firing rate. In this study, we examined whether DA neurons in the adjacent substantia nigra (SN) also display a SO. DA neurons were recorded extracellularly using the cells/track technique in chloral hydrate‐anesthetized rats. Spectral analysis showed that firing patterns of SN DA neurons exhibited a SO similar to that observed in VTA DA neurons. The amplitude of the SO, however, was much reduced in the SN compared with that in the VTA and so was the number of DA neurons qualified as high‐SO cells. In high‐SO DA neurons, the amplitude of the SO was strongly correlated with the degree of bursting, and this correlation was observed in both the VTA and SN. In low‐SO cells, however, the SO was more significantly correlated with the variability of firing than with firing rate and bursting. Since the generation of the SO depends on afferent inputs to DA neurons, a better understanding of its difference between the SN and VTA may provide important insights into the neural networks that control DA neurons in the two areas. Synapse 62:169–175, 2008. © 2007 Wiley‐Liss, Inc.
The enduring effects of an adolescent social stressor on synaptic density, part II: Poststress reversal of synaptic loss in the cortex by adinazolam and MK‐801
Authors: Leussis Melanie P. , Lawson Katherine , Stone Kimberly , Andersen Susan L.
Published: December 2007

Experience programs synaptic development to match the needs of the environment. This process depends on the nature and timing of the experience. Exposure to stress during adolescence selectively reduces synaptic density in the prefrontal cortex (a later maturing region), while sparing hippocampal synapses (an earlier maturing region). To determine whether the anatomical effects of an adolescent social stressor in rats endures into adulthood and are reversible, male subjects were isolation or group housed between days 30 and 35 and then treated with vehicle, adinazolam, MK‐801, or tianeptine between days 40 and 55. At day 60, immunohistochemistry revealed a 13.5% ± 5.3% reduction in synaptophysin in the infralimbic cortex and cingulate gyrus in isolation‐housed subjects. MK‐801 and adinazolam restored cortical synaptic density to within 2% of group‐housed values, suggesting that the synaptic loss induced by stress during adolescence is modulated through reduced glutamatergic activity directly by NMDA antagonism or indirectly by enhancing GABAergic activity. Tianeptine did not modulate adolescent stress effects in the prefrontal cortex. None of these drugs increased cortical synaptophysin in group‐housed controls. Increased synaptophysin was observed in the group‐housed condition in the hippocampus, striatum, and nucleus accumbens following drug exposure. Although stress did not decrease synaptic density in these regions, drug exposure failed to increase synaptic density when compared with the controls. Taken together, stress‐induced changes in cortical, but not hippocampal, synaptic density initiated during adolescence endure into adulthood. These cortical changes can be reversed through a reduction of glutamatergic activity, but not serotonin augmentation. © 2007 Wiley‐Liss, Inc. Synapse 62:185–192, 2008.
Identification and Characterization of Hamster Stearoyl‐CoA Desaturase Isoforms
Authors: Wang Jian , Yu Lan , Wang He , Gao Yunling , Schrementi James P. , Porter Regina K. , Yurek David A. , Kuo Mingshang , Suen Chen‐Shian , Cao Guoqing , Bean James S. , Kauffman Raymond F. , Qian Yuewei
Published: December 2007

Stearoyl‐CoA desaturase (SCD) catalyzes the formation of monounsaturated fatty acids from saturated fatty acids. It plays a key role in lipid metabolism and energy expenditure in mammals. In mice, four SCD isoforms (SCD1–4) have been identified. Here we report the identification of cDNA sequences corresponding to SCD1, SCD2 and SCD3 of golden hamster. The deduced amino acid sequences of these hamster SCD (hmSCD) isoforms display a high degree of homologies to their mouse counterparts (mouse SCD). Polyclonal antibodies specific to rodent SCDs detected proteins of predicted size in the human embryonic kidney 293 cells transfected with hmSCD cDNAs. Microsome fractions prepared from these cells also displayed increased SCD activity versus cells transfected with vector alone. Real‐time reverse transcription‐polymerase chain reaction analysis revealed the highest expression of hmSCD1 in liver and adipose tissue, while the highest hmSCD2 expression was detected in the brain. Very low levels of hmSCD3 mRNA can be detected in the tissues tested. This report is the first description of three SCD isoforms in the hamster and will provide useful tools in the further study of fatty acids metabolism in this species.
Associations between orthopaedic findings, ambulation and health-related quality of life in children with myelomeningocele
Authors: Danielsson Aina J. , Bartonek Åsa , Levey Eric , McHale Kathleen , Sponseller Paul , Saraste Helena
Published: December 2007

Purpose

Modern principles for treatment of patients with myelomeningocele include early closure of the neural tube defect, neurosurgical treatment of hydrocephalus and treatment aimed at minimizing contractures and joint dislocations. The aim is to achieve a better survival rate and a better quality of life (QOL). Better ambulatory function is thought to improve the management of activities of daily living. This study focused on evaluating which factors might affect ambulation, function and health-related QOL in children with myelomeningocele.

Methods

Thirty-eight patients with neurological deficit from myelomeningocele were examined in an unbiased follow-up. This included a physical examination using validated methods for ambulatory function and neuromuscular status, chart reviews and evaluation of radiographs in terms of hip dislocation and spine deformity. The Pediatric Evaluation of Disability Inventory (PEDI) was used to measure mobility, self-care and social function, and the Child Health Questionnaire (CHQ-PF50) was used to measure QOL.

Results

Muscle function class, quadriceps strength, spasticity in hip and/or knee joint muscles and hip flexion contracture as well as the ambulatory level all affected functional mobility as well as self-care/PEDI. Patients with hip dislocation, spinal deformity or those who were mentally retarded also had significantly worse functional mobility. Besides being affected by the severity of the neurological lesion, self-care/PEDI was significantly impaired by hip flexion contracture and absence of functional ambulation. General health-related QOL was significantly lower in this patient group than for US norms. Nonambulatory and mentally retarded patients had a significantly lower physical function of their QOL (CHQ).

Conclusions

The severity of the disease, i.e. reduced muscle strength and occurrence of spasticity around hip/knee, affected ambulation, functional mobility and self-care. Acquired deformities (hip dislocation and spine deformity) affected functional ambulation only. Patients with reduced functional mobility and self-care experienced lower physical QOL. Children with myelomeningocele had significantly reduced QOL compared to healthy individuals.
Experiments on gas transfer at the air–water interface induced by oscillating grid turbulence
Authors: HERLINA  , JIRKA G. H.
Published: December 2007

The gas transfer process across the air–water interface in a turbulent flow environment, with the turbulence generated in the water phase far away from the surface, was experimentally investigated for varying turbulent Reynolds numbersReTranging between 260 and 780. The experiments were performed in a grid-stirred tank using a combined particle image velocimetry – laser induced fluorescence (PIV-LIF) technique, which enables synoptic measurements of two-dimensional velocity and dissolved gas concentration fields. The visualization of the velocity and concentration fields provided direct insight into the gas transfer mechanisms. The high data resolution allowed detailed quantification of the gas concentration distribution (i.e. mean and turbulent fluctuation characteristics) within the thin aqueous boundary layer as well as revealing the near-surface hydrodynamics. The normalized concentration profiles show that asReTincreases, the rate of concentration decay into the bulk becomes slower. Independent benchmark data for the transfer velocityKLwere obtained and their normalized values (KLSc0.5/uHT) depend onReTwith exponent −0.25. The spectra of the covariance termc′w′ indicate that the contribution ofc′w′ is larger in the lower-frequency region for cases with smallReT, whereas for the other cases with higherReT, the contribution ofc′w′ appears to be larger in the higher-frequency region (small eddies). These interrelated facts suggest that the gas transfer process is controlled by a spectrum of different eddy sizes and the gas transfer at different turbulence levels can be associated with certain dominant eddy sizes. The normalized mean turbulent flux$\overline{c^\prime w^\prime}$profiles increase from around 0 at the interface to about 1 within a depth of approximately 2δe, where δeis the thickness of the gas boundary layer. The measured turbulent flux (c′w′) is of the same order as the total flux (j), which shows that the contribution ofc′w′ to the total flux is significant.
New species and new records of the lichen genus Caloplaca from India
Authors: JOSHI Yogesh , UPRETI Dalip K.
Published: December 2007

Caloplaca tropica Y. Joshi & Upreti, is described as new to science and belongs to the Sideritis group in the lichen genus Caloplaca. Caloplaca hueana (section Cocciniodiscus), C. squamosa (Squamosa group) and C. pollinii are reported for the first time from India.
A chemotaxonomic study of Lethariella zahlbruckneri and L. smithii (lichenized Ascomycota: Parmeliaceae) from Hengduanshan Mountains
Authors: NIU Dong-ling , WANG Li-song , ZHANG Ying-jun , YANG Chong-ren
Published: December 2007

A taxonomic investigation of Lethariella smithii and L. zahlbruckneri has established that they are conspecific. Three chemical races are recognized: race 1 containing norstictic acid, race 2 norstictic acid and placodiolic acid, and race 3 placodiolic acid as major medullary substances.
Lecania belgica van den Boom & Reese Næsborg, a new saxicolous lichen species from western Europe
Authors: REESE NÆSBORG Rikke , VAN DEN BOOM Pieter P. G.
Published: December 2007

A new species, Lecania belgica, is described and illustrated. It is a saxicolous lichen known only from the type locality in Belgium. It is characterized by apothecia with pruinose, irregularly undulating discs, relatively short ascospores, and by having 12–16 spores in the asci. It was found on mortar together with Diplotomma alboatrum.
Mental rotation of congenitally absent hands
Authors: FUNK MARION , BRUGGER PETER
Published: December 2007

We compared motor imagery performance of normally limbed individuals with that of individuals with one or both hands missing since birth (i.e., hand amelia). To this aim, 14 unilaterally and 2 bilaterally amelic participants performed a task requiring the classification of hands depicted in different degrees of rotation as either a left or a right hand. On the same task, 24 normally limbed participants recapitulated previously reported effects; that is, that the hand motor dominance and, more generally, a lifelong use of hands are important determinants of left–right decisions. Unilaterally amelic participants responded slower to hands corresponding to their absent, compared with their existing, hand. Moreover, left and right hand amelic participants showed prolonged reaction times to hands (whether left or right) depicted in unnatural orientations compared with natural orientations. Among the bilateral amelics, the individual with phantom sensations, but not the one without, showed similar differentiation. These findings demonstrate that the visual recognition of a hand never physically developed is prolonged, but still modulated by different rotation angles. They are further compatible with the view that phantom limbs in hand amelia may constrain motor imagery as much as do amputation phantoms. (JINS, 2008,14, 81–89.)
Paging equals functionality
Authors: GRAFMAN JORDAN
Published: December 2007

There are a number of devices now used in automobiles that allow subscribed companies to track the car and to aid the owner in the case of accidents, lockouts, being lost, etc. Even in the age of the cell-phone, having a human whom you can routinely contact and who is paid to help you when a problem occurs is reassuring. Given the forthcoming graying of the baby boomers with a significant proportion of us developing a dementia, along with the large number of people who suffer head injuries, strokes, and similar disorders, the market for a similar device, worn on the body—perhaps as a secured bracelet—appears obvious. Compensatory aids may have an important role to play in helping patients become functional—particularly when used as a reminder, to orient them to time and place, or to provide a human voice to give instructions when necessary. Since one operator potentially can handle many patients at the same time, it could be a cost-effective device to obtain. I say “may have an important role” because very few studies have used such a device, much less carefully evaluated its usefulness. In this issue, Fish, Manly, and Wilson (2008) describe a very nice application of a single-case design to evaluate the use of a compensatory device in a patient with a frontal lobe lesion associated with deficits in planning that were characterized as goal-neglect by the authors.
THE DIFFERENTIAL STAINING OF HUMAN AND DOG SPERMATOZOA
Authors: Wales RG
Published: December 2007

Human spermatozoa can be stained successfully with trypan blue, eosin and erythrosin and although each stain gives a difference in the estimate of “live” cells in a sample, this difference is consistent for each ejaculate, before and after heat treatment.

It is suggested that because of the relative simplicity of the procedure, eosin‐nigrosin should be used routinely to stain human spermatozoa.

Eosin‐nigrosin should be used in preference to congo red‐nigrosin as a vital stain for dog spermatozoa as it gives better differentiation, a variance estimate which is more consistent with that expected from theory and less difference between operators.

The percentage of stained spermatozoa in a semen‐eosin mixture has been found to increase with time of exposure to the stain. This effect was seen with both dog and human spermatozoa.
STUDIES ON THE ESTIMATION OF GLYCEROL, FRUCTOSE AND LACTIC ACID WITH PARTICULAR REFERENCE TO SEMEN
Authors: White IG
Published: December 2007

Zinc sulphate and either barium hydroxide or sodium hydroxide are suitable deproteinizing agents for estimating glycerol, fructose or lactic acid in semen.

The stability of the glycerol and lactic acid colour is fairly good. The fructose colour, however, is likely to increase appreciably on standing for an hour unless the tubes are heated for 20 minutes at 80–85°C. instead of the usual 10 minutes.

Potassium metaperiodate is preferable to sodium paraperiodate in the estimation of glycerol as it gives a calibration curve with a steeper slope.

The glycerol method can be used for the estimation of glycerylphosphorylcholine in semen if fructose is first removed by copper‐lime treatment.

Barium‐zinc extracts of fructose and lactic acid were found to be stable normally for several weeks in a refrigerator. Contamination with yeast organisms can, however, cause a rapid fall in the fructose content.
THE PERMEABILITY OF LIVER AND SKIN CAPILLARIES TO LIPIDS IN THE CAT
Authors: Courtice FC
Published: December 2007

Lymph was collected from the hepatic and leg ducts of cats before and after the intravenous infusion of artificial fat emulsions, homologous chyle and heterologous hypercholesterolaemic plasma.

The fat particles of the artificial fat emulsion appeared in the hepatic lymph in quantities similar to those previously found for chyle. In the paw there was only a very little transfer of the particles of artificial fat emulsion and chyle from plasma to lymph even after injuring the skin by a thermal burn. The smaller lipid complexes of hypercholesterolaemic rabbit plasma, however, penetrated the capillary membrane and appeared in the lymph.

The mechanisms of transfer in the liver and in the skin have been discussed.
THE EFFECT OF SALICYLATE ON PLASMA PROTEIN BOUND IODINE IN MAN
Authors: Charnock John S , Good Brian F , Hetzel Basil S
Published: December 2007

The effect of a large single oral dose (5 gm.) of sodium salicylate on plasma PBI has been compared with that of a similar dose of sodium parahydroxybenzoate.

Although a significant fall in plasma PBI occurred after two hours following both agents, the fall with salicylate was significantly greater (P < 0·05).

A similar fall in plasma PBI was observed in a diabetic patient given salicylate in a dosage of 60–100 grains per day with a plasma salicylate level of 21–31 mg. p.c.

The possible mechanisms involved are discussed and it is concluded that the effect may be due to an action on the feed back mechanism for thyroid hormone in the hypothalamus.
THE HAEMATOLOGY OF THE CENTRAL AUSTRALIAN ABORIGINE
Authors: Casley‐Smith JR
Published: December 2007

Total leukocyte and differential counts were performed on a group of aborigines. These lived under semi‐detribalized conditions at Haast's Bluff. A control series was taken of Europeans living at Adelaide.

The total leukocyte and absolute lymphocyte counts were slightly but significantly raised in the aborigines. The eosinophil counts were markedly increased in the aborigines.

Direct eosinophil counts were performed on nomads visiting Haast's Bluff. These also had greatly raised values. Many of them had positive Casoni tests. Those with positive tests had more eosinophilia than those with negative reactions. Hospital natives had fewer positive reactions.
A STUDY OF THE METASTATIC DISTRIBUTION OF ERLICH ASCITES TUMOUR CELLS IN MICE
Authors: Selecki EE
Published: December 2007

The introduction of a method of labelling ascites tumour cells with radioactive chromium has facilitated a quantitative study of metastasis of these cells.

A rapid rate of removal of tumour cells from the blood stream takes place in the first 15 minutes after the intravenous injection of labelled tumour cells, and a corresponding rise in the number of tumour cells lodged in the lungs is observed at this time.

A constant release of tumour cells from the lungs into the systemic circulation occurs immediately after the intravenous injection. The release is relatively slight in the first three hours, but after 24 hours only 5 p.c. of the number of cells accumulated remain in the lung.

The liver accumulates about 20 p.c. of the total number of cells injected in the first six hours. The subsequent disappearance of the cells from the organ is slow.

A steady accumulation of cells is observed in the spleen up to the third day after injection. The total number of cells reaching the spleen is small, but the concentration per gram of splenic tissue is relatively high.
PLASMA CELL PROLIFERATION FOLLOWING WHOLE BODY IRRADIATION
Authors: Nossal GJV
Published: December 2007

The effects of large doses of whole body irradiation on lymphoid tissues have been studied, with special reference to the normal plasma fell populations of the tissues. Plasma cells were found to be more radioresistant than lymphocytes.

After a sublethal dose of 500 r of whole body X‐rays, considerable plasma cell proliferation followed. This plasma cell proliferation occurred earlier and was relatively more extensive than lymphocyte regeneration.

The view is put forward that the plasma cell proliferation might represent an antibody response to invading micro‐organisms entering the irradiated animal via the damaged gastrointestinal tract.
THE ESTABLISHMENT OF A STRAIN OF HUMAN CELLS IN TISSUE CULTURE
Authors: Larkin Maureen F
Published: December 2007

A strain of human cells–B‐184–has been grown continuously in tissue culture for over 12 months. The cells are maintained easily in simple fluid medium on glass. They can be stored successfully at –50°C, for at least four mouths. Poliovirus multiplied within these cells and produced cytopathogenic effects.
SERUM MAGNESIUM‐CHOLESTEROL RELATIONSHIPS IN THE CENTRAL AUSTRALIAN ABORIGINE AND IN EUROPEANS WITH AND WITHOUT ISCHAEMIC HEART DISEASE
Authors: Charnock John S , Casley‐Smith John , Schwartz Colin J
Published: December 2007

The serum cholesterol level of Australian aborigines has been shown to be significantly lower than that of Australian controls of European descent, living either in Adelaide or Alice Springs.

The serum magnesium level of the Australian aborigine was greater than that of European controls, living in or near Adelaide; but was less than that of the European controls living in the Alice Springs area.

A relationship between the serum magnesium and cholesterol levels was not demonstrated by correlation coefficients.

The reason for the difference between the cholesterol levels of Australian aborigines and Europeans is, of course, speculative, but could be assigned to a difference of dietary fat. Similarly the difference in magnesium levels existing between Europeans in Adelaide and all racial groups in Alice Springs could be assigned to either a higher intake of magnesium or to climatic conditions such as dehydration.
THE HAEMATOLOGY OF THE CENTRAL AUSTRALIAN ABORIGINE
Authors: Casley‐Smith JR
Published: December 2007

Blood films of 30 aborigines and 30 Europeans were studied to obtain neutrophil and lymphocyte haemograms.

The aborigines had an increased proportion of young cells in both cases.

It was held that these results show that the observed leukocytosis is due to increased cell production. This may be due to the greater, long continued “stress” of the aborigines' environment.
DETERMINATION OF SERUM CHOLESTEROL WITH PERCHLORIC ACID
Authors: Brown WD
Published: December 2007

An exceptionally stable and sensitive method for serum cholesterol determination is described. A source of error in determination of serum cholesteryl esters without saponification is described and this is related to accuracy of estimates obtained for cholestery esters isolated on silicic acid.
THE EFFECT OF THE LEVEL OF DIETARY FAT ON THE TOXICITY OF PHENOLIC ANTIOXIDANTS
Authors: Brown WD , Johnson AR , O'Halloran MW
Published: December 2007

A study was made of the effect of two antioxidants, butylated hydroxy anisole (BHA) and butylated hydroxy toluene (BHT), with variation in the type and quantity of dietary fat, on growth, food consumption, reproduction, mortality, organ weights and post‐mortem pathology of the rat.

The normal cellular behaviour of experimental animals fed diets containing one hundred times the amount of the antioxidant normally expected to be present in human foods (normal testing dose, NTD), is the conventional yardstick of non‐toxicity.

The NTD of BHA produced no apparent changes in any of the parameters measured. When BHT was fed at a dietary level of 0·1 p.c. (the NTD) in conjunction with a 20 p.c. lard supplement, it significantly reduced the initial growth rate and mature weight of male rats. No such significant effect was noted in female rats or in male rats with a 10 p.c. lard supplement. A paired feeding experiment showed that this inhibition of growth was a direct toxic effect of BHT and could not be explained by a reduction in the palatability of the diet.

At the NTD, BHT produced a significant increase in the weight of the liver relative to the body weight. The mean absolute weight of the liver was also increased.

A significant loss of hair on the top of the head occurred in animals whose diet contained the NTD of BHT. This effect was only noted in animals under conditions of increased stress and was enhanced by an increase in the lard content of the diet. Anophthalmia occurred in 10 p.c. of the litters born of parents fed BHT.

Even when present in the diet at a concentration of 0·5 p.c., BHA and BHT had no effect on one reproductive cycle of the rat, or the histology of the spleen, kidney, liver, testes or skin, or the ratio to total body weight of the weight of the heart, spleen and kidney.

If the conventional NTD be accepted, BHA fulfilled the requirements of non‐toxicity. BHT, at the NTD, on the other hand, produced deleterious deviations from normal cellular behaviour which cast doubt on the advisability of permitting this antioxidant in foodstuffs for human consumption.
CANINE OVARIAN TUMOURS FOLLOWING STILBOESTROL ADMINISTRATION
Authors: Jabara Anne G
Published: December 2007

Infection of diethylstilboestrol into a group of eight dogs was followed, within nineteen months, by development of tumours of the ovary in all cases.

One of these was an hyperplasia and seven were definite neoplasms. The neoplastic nature of these was shown by invasion and development (in 3 cases) of metastases.

The tumours showed, in these cases, a multiplicity of tissues not seen in tumours in man.

The high yield indicates a specific activity of the injected material, either the stilboestrol itself or a metabolite, or its physiological activity provides a bulk of tissue on which some carcinogen acts.
THE INHIBITORY EFFECT OF SALICYLATE ON THE RELEASE OF HISTAMINE BY VENOM IN THE PRESENCE OF BLOOD
Authors: Trethewie ER , Morris CW
Published: December 2007

The output of histamine from two lobes of the one dog liver is similar when salicylate is perfused through one of them at a concentration of 100 mg. p.c. and the perfusing fluid in each is Tyrode.

There is a 50 p.c. reduction in output of histamine under similar circumstances, when salicylate is used in a concentration of 90 mg. p.c. and the perfusing fluid through each is diluted blood and Tyrode.
TOXOPLASMA IN QUEENSLAND
Authors: Cook Ian
Published: December 2007

Complement‐fixing antibodies were detected in 13 p.c. and dye‐test antibodies in 24 p.c. of 760 sera from the general population.

The incidence of antibodies was less in a small series from western Queensland.

Analysis by age suggests that dye‐test antibodies do not persist permanently, as has been generally believed.

Of 133 patients with diseases of the eye, 28 p.c. had complement‐fixing antibodies and 39 p.c. dye‐test antibodies in their sera, while, in 215 patients with glandular conditions, the incidence was 19 p.c. and 24 p.c. respectively.

Five cases of congenital toxoplasmosis were diagnosed serologically in children with choroiditis, and a rise in titre was demonstrated in the serum of an adult with glandular enlargement.

Dye‐test antibodies were also found in the sera of 39 p.c. of 49 aborigines on the east coast of Cape York Peninsula. On the west coast, antibodies were detected in 19 p.c. of 180 aborigines of the northern and central missions and in none of 60 in the south. Dye‐test antibodies were also found in 23 p.c. of 83 Papuans.
A HIGH FREQUENCY PULSE GENERATOR FOR INJURING TISSUE WITHIN THE SANDISON‐CLARK RABBIT EAR CHAMBER
Authors: Buckley IK , Semkiw J
Published: December 2007

A radio‐frequency pulse generator capable of inflicting variable but reproducible thermal injuries on tissue within the Sandison‐Clark rabbit car chamber is described. A technique facilitating the production of very small injuries at any chosen site within the car chamber is outlined. Some of the applications for the technique are discussed.
SOME OBSERVATIONS ON THE PRODUCTION OF BILE BY THE ISOLATED PERFUSED LIVER OF THE RAT
Authors: Morris Bede
Published: December 2007

A method for perfusing the isolated liver of the rat in a gas‐tight system is described. Under the conditions of the experiments, the livers produced bile and metabolized fat for several hours.

Some observations on the effect of temperature, perfusion pressure and the concentration of fat in the perfusate on the production of bile are reported. It was found that the production of bile was maximal at 38°C. At temperatures of 32 and 42°C., bile flow was significantly reduced. The volume of bile produced was related to the perfusion pressure and increased as the pressure was raised from 5 to 25 cm. of blood. The concentration of fat in the perfusate had no effect on bile production.

There was a significant interaction effect between temperature and perfusion pressure which was thought to be explained by the oxygen requirements of the liver cells in relation to blood flow and bile secretion. The results suggested that bile secretion reached a maximum when all the hepatic sinuses were perfused, provided the oxygen supply to the liver cells was adequate.