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Magnetic skyrmions are candidates for information carriers in Brownian and stochastic computers. Developing a technique for fabricating a film with a suitable potential landscape, wherein the information carrier may diffuse freely, is essential for these probabilistic computers. In this study, to build the desired local potential into magnetic films, a 1.2 nm-thick Co-Fe-B film with a 5.2 nm-thick cap layer was irradiated by a focused ion beam (FIB) using Ga+ as the ion source under a low acceleration voltage of 5 keV. The fluences ranged from 0 to 25 × 1012 ions/cm2. Consequently, the critical temperature at which skyrmions appear or disappear is shifted by several 1–10 K depending on the ion fluence. The origin of this effect is discussed by observing the ion implantation profile and the surface sputtering depth using time-of-flight secondary ion mass spectrometry (TOF-SIMS) and atomic force microscopy (AFM). The results of TOF-SIMS measurements show that most of the Ga atoms exist in the Co–Fe–B layer. If all Ga atoms exist in the Co–Fe–B layer, the Ga concentration is 7 × 10−3 at. % after irradiation of 0.8 × 1012 ions/cm2. The AFM results show a sputtered pattern with 0.2 nm depth after irradiation of 16 × 1012 ions/cm2. Finally, the effect of irradiation on the diffusion coefficient was examined. It was determined that small fluences of 1.6 × 1012 and 0.8 × 1012 ions/cm2 can construct a potential barrier controlling skyrmions while maintaining diffusion coefficients as high as 10 μm2/s. The FIB process can be used to draw a circuit of probabilistic computers with skyrmions as information carriers.

Since skin on the lips has a lower water content in the stratum corneum (SC) and a higher transepidermal water loss (TEWL) value than skin on the cheek, the lips are usually very dry and rough areas. Therefore, a lip balm approach to increase occlusivity of the lips is generally used to reduce water loss. Although there have been reports of an improvement effect on lip roughness by specific care agents, differences in the effects due to the occlusivity of a formulation without a specific care agent have not been reported. The purpose of this study was to clarify the improvement effect on dryness and roughness of the lips by a highly occlusive formulation consisting of a combination of common oil and wax, not by a specific care agent.Twenty Japanese female subjects with normal skin (age range 20-39 years; mean 28.1) were enrolled in this study. A 4-week continuous use test was conducted using samples with low and high occlusivity. The degree of lip roughness and wrinkles was scored, the hollow index was assessed using ANTERA 3D images, and values of capacitance and TEWL were measured.The hollow index was significantly correlated with both the appearance roughness score and the wrinkle score. The sample with high occlusivity showed significant improvement in the appearance roughness score, wrinkle score, the hollow index and capacitance of the SC. In a comparison between the groups of samples with different occlusive properties, a significant improvement effect in rough appearance was seen in subjects using the highly occlusive formulation.The hollow index assessed by ANTERA 3D imaging allowed the objective evaluation of the improvement in appearance. In the case of continuous use of the highly occlusive formulation, an improvement of capacitance in the SC, which is most correlated with lip roughness, was obtained after 2 and 4 weeks. These results demonstrate for the first time that a highly occlusive formulation is effective in improving the roughness of the lips, and this effect is due to the difference in the occlusive property not by a specific care agent.La peau qui recouvre les lèvres ayant une plus faible teneur en eau dans la couche cornée (CC) et une valeur de perte d’eau transépidermique (PETE) plus élevée que la peau des joues, les lèvres sont généralement des zones très sèches et rugueuses. Par conséquent, l’utilisation d’un baume à lèvres pour augmenter l’occlusivité des lèvres est généralement l’approche adoptée pour réduire la perte d’eau. Même s’il y a eu des rapports d’un effet d’amélioration de la rugosité des lèvres grâce à des agents de soin spécifiques, aucune différence par rapport aux effets dus aux propriétés occlusives d’une formule ne contenant pas un agent de soin spécifique n’a été rapportée. Le but de cette étude était de clarifier l’effet d’amélioration de la sécheresse et de la rugosité des lèvres d’une formule hautement occlusive composée d’une association d’huile et de cire courantes, et non pas d’un agent de soin spécifique. MÉTHODES: Vingt sujets de sexe féminin japonais ayant une peau normale (tranche d’âge : 20 à 39 ans ; moyenne : 28,1) ont été inclus dans cette étude. Un test d’utilisation continue pendant 4 semaines a été mené en utilisant des échantillons ayant des propriétés occlusives faibles et élevées. Le degré de rugosité et de ridules des lèvres a été noté, l’indice de creux a été évalué à l’aide d’images 3D ANTERA, et les valeurs de capacitance et de PETE ont été mesurées. RÉSULTATS: L’indice de creux était significativement corrélé avec le score de l’aspect de rugosité et le score de ridules. L’échantillon comportant des propriétés occlusives élevées a démontré une amélioration significative du score de l’aspect de rugosité, du score de ridules, de l’indice de creux et de la capacitance de la CC. Dans une comparaison entre les groupes d’échantillons comportant différentes propriétés occlusives, une amélioration significative de l’effet sur l’aspect rugueux a été observée chez les sujets utilisant la formule aux propriétés occlusives élevées.L’indice de creux évalué par l’imagerie 3D ANTERA a permis d’effectuer une évaluation objective de l’amélioration de l’aspect. Dans le cas d’une utilisation continue de la formule aux propriétés occlusives élevées, une amélioration de la capacitance de la CC, qui était le plus corrélée avec la rugosité des lèvres, a été atteinte au bout de 2 et 4 semaines. Ces résultats montrent pour la première fois qu’une formule aux propriétés occlusives élevées est efficace dans l’amélioration de la rugosité des lèvres, et cet effet est dû à la différence dans les propriétés occlusives et non pas à un agent de soin spécifique.

OBJECTIVE Lips can easily become dry and rough, one reason being the characteristics of their ceramide (CER) profile. Lips have lower levels of total ceramides, higher percentages of CER[NS] and CER[AS], and lower percentages of CER[NP] and CER[NH] than skin in other regions of the body. The purpose of this study was to clarify the effects of synthetic pseudo‐ceramide (pCer; Cetyl‐PG hydroxyethyl palmitamide) to improve the dryness and roughness of the lips of healthy subjects in a formulation that exclude an occlusive effect. METHODS Thirty‐one Japanese female subjects with normal skin (age range 21–37 years; mean 28.6) were enrolled in this study. A four‐week continuous use test was conducted using samples with or without 0.5% or 2.0% pCer. The degree of lip roughness was scored, and values of capacitance, transepidermal water loss (TEWL) and lip surface elasticity were measured. Endogenous CER profiles and absorption levels of pCer in the stratum corneum (SC) were analysed in tape‐stripped skin specimens. RESULTS Treatment with the pCer‐2.0% sample significantly improved the visual roughness score after 2 and 4 weeks compared to 0 weeks and compared to the Blank. Moreover, an improvement in TEWL was observed after 4 weeks of treatment with the pCer‐2.0% sample. CER[NP] showed a significant increase in pCer‐2.0% treated lips after 4 weeks compared to the Blank. Both pCer‐0.5% and pCer‐2.0% were significantly absorbed after 2 weeks compared with the Blank. CONCLUSION The effect of the synthetic pseudo‐ceramide pCer to improve the roughness of lips was shown excluding the effect of occlusiveness derived from the formulation for the first time. Since the improvement of TEWL and absorption of pCer was observed, we concluded that pCer was first absorbed in rough lip areas, improved the ceramide profile and consequently restored the barrier function., For the first time, the effect of the synthetic pseudo‐ceramide pCer to improve the roughness of the lips was shown excluding the effect of occlusiveness derived from the formulation. pCer was first absorbed in rough lip areas, improved the ceramide profile and consequently restored the barrier function.

Background/aims Lips can easily become dry and rough and their biggest problems are drying and chapping. The cause of those problems is considered to be that the stratum corneum (SC) moisture is small and its barrier function is low. However, those problems decrease in subjects as they approach 40 years of age, after which problems due to their shape and color increase. The purpose of this study was to investigate relationships between SC properties of the lips during aging and to clarify the cause(s) of lip problems. Methods One hundred and 38 Japanese female subjects with normal skin ranging in age from 16 to 78 years were enrolled in the study. The capacitance and transepidermal water loss (TEWL) values, viscoelasticity, and color of their lips were measured and compared with their cheeks. Results The capacitance values for the lip and the cheek increased and TEWL values for both areas decreased with age. TEWL values for the lip decreased until ~30 years of age and this is considered to be related to the problem of drying. Although the maximum amplitude Uf of the lip increased with age, the Ur /Uf had no correlation with age. As for color, the L* and a* values decreased with age. Conclusion Age-related changes with regard to SC functions, viscoelasticity and color of the lips have been clarified for the first time, and it is clear that these changes are related to problems of the lips. Compared with the cheeks, differences with the lips are more apparent.

Cancer therapies that target a single protein or pathway may be limited by their specificity, thus missing key players that control cellular proliferation and contributing to the failure of the treatment. We propose that approaches to cancer therapy that hit multiple targets would limit the chances of escape. To this end, we have developed a bicistronic adenoviral vector encoding both the CDKN2A and p53 tumor suppressor genes. The bicistronic vector, AdCDKN2A-I-p53, supports the translation of both gene products from a single transcript, assuring that all transduced cells will express both proteins. We show that combined, but not single, gene transfer results in markedly reduced proliferation and increased cell death correlated with reduced levels of phosphorylated pRB, induction of CDKN1A and caspase 3 activity, yet avoiding the induction of senescence. Using isogenic cell lines, we show that these effects were not impeded by the presence of mutant p53. In a mouse model of in situ gene therapy, a single intratumoral treatment with the bicistronic vector conferred markedly inhibited tumor progression while the treatment with either CDKN2A or p53 alone only partially controlled tumor growth. Histologic analysis revealed widespread transduction, yet reduced proliferation and increased cell death was associated only with the simultaneous transfer of CDKN2A and p53. We propose that restoration of two of the most frequently altered genes in human cancer, mediated by AdCDKN2A-I-p53, is beneficial since multiple targets are reached, thus increasing the efficacy of the treatment.

Visual observations reveal a complicated flow in the liquid melt and a melting front configuration resulting from horizontal ice plate melting from above into a 20 wt% calcium chloride aqueous solution. The initial temperature of the ice plate and the mixture are both −5°C. Small scale “mountain and valley” structures (∼1 mm) appear on the flat melting front just after melting begins, which have been called “sharkskin”. Innumerable upward and downward flows appear near the sharkskin and are controlled by its “mountain and valley” structure. These typical flows will considerably promote the melting of the ice plate to be 30% larger as compared to the numerically predicted results assuming a flat melting front (i.e., without the sharkskin), and also by three times larger compared with the results for melting from below.

A strong dependence of tunnel magnetoresistance (TMR) on the crystal orientation of ferromagnetic electrodes was confirmed experimentally. We studied the TMR of Fe/Al2O3/Fe50Co50 tunnel junctions with single-crystal Fe electrodes of different crystal orientations and found that the TMR ratio increased from 13% to 42% at 2K (8% to 26% at room temperature) when the crystal orientation was changed from (100) to (211). Such a TMR anisotropy could be explained in terms of the anisotropic spin polarization of Fe bulk and/or interface electronic states. The importance of the "momentum-filtering" effect of the tunnel barrier was also discussed.

The Schottky barrier height (SBH) of MnSb(0001)/n-GaAs(111)B diodes was investigated in terms of current-voltage characteristics for three different GaAs surfaces, GaAs (root 19x root 19), GaAs (2x2), and sulfur passivated GaAs. We observed that the SBH and the ideality factor changed significantly depending on the GaAs surface structure prepared before the MnSb growth. The sulfur passivated sample was superior to the others in that it has a lower ideality factor and higher barrier. The SBH fell off linearly with increasing ideality factor n. The SBH of MnSb(0001)/n-GaAs(111)B was estimated to be 0.94 eV by extrapolating the linear relationship to n=1. (C) 2000 American Institute of Physics. [S0021-8979(00)02916-9].

In this paper, we investigate the origin of spurious signals in the GaAs-tip-based spin-polarized scanning tunneling microscope setup. Experimentally as well as theoretically, dichroism and birefringence are found to induce a power modulation signal up to a 10% depth. In particular, the presence of dichroism fluctuations in the sample's substrate, at a submicronic scale and of non-magnetic origin, led to the formation of an image showing a domain-like structure on a mica/Au (10 nm) non-magnetic sample. As a conclusion, this parasitic signal is therefore competing with the expected spin-dependent tunneling conductance phenomenon. Finally, we discuss of a new image obtained with a high-quality, microfabricated tips, where both phenomena may be present at the same time.

Magneto-optical response of the wedge-shaped Au ultrathin film grown on an Fe layer was investigated precisely. The magnetic circular dichroism in the reflection configuration oscillates with respect to the Au layer thickness showing superposition of several oscillations with different periods. The energy dependence of the oscillation periods is clearly explained by a concept of the spin-polarized quantum size effect in the Au layer by employing fully relativistic band calculation and electron-electron correlation.

A new furnace, based on a halogen lamp, and a sample cell have been designed and constructed for in situ X-ray absorption spectroscopy experiments in conventional and dispersive mode (transmission and fluorescence geometries). The main application of the apparatus is thermal treatment studies under controlled conditions for dynamical processes. The sol-gel (gelatin) method has been utilized to synthesize NiO nanoparticles. During this heating process, in situ Ni K-edge X-ray absorption near-edge structural measurements provided evidence of the evolution of a Ni environment until complete NiO nanoparticle crystallization. This case is reported in order to show the furnace performance in dispersive mode.

This paper describes QDsim, a parallel application designed to compute the quantum concurrence by calculating the Wootters correlation of a quantum system. The system is based on a two-level two quantum dots inside a resonant cavity. A Beowulf-like cluster was used for running QDsim. The application was developed using open, portable and scalable software and can be controlled via a GUI client from a remote terminal over either the Internet or a local network. A serial version and three parallel models (shared memory, distributed memory and hybrid –distributed/shared memory) using two different partitioning schemes were implemented to assess their performance. Results showed that the hybrid model approach using domain decomposition achieves the highest performance (12.2X speedup in front of the sequential version) followed by the distributed memory model (6.6X speedup). In both cases, the numerical error is within 1×10− 4, which is accurate enough for estimating the correlation trend.

This paper describes the small-angle scattering beamline built at the Brazilian Synchrotron Light Laboratory (LNLS). Vertical focusing of the synchrotron beam is achieved by an elastically bent gold-plated cylindrical mirror. An asymmetric cut curved triangle-shaped silicon single crystal (111 reflection) is used for monochromatization and horizontal focusing. The mirror, monochromator optics and 2θ arm were designed to cover the spectral range between 1.0 and 2.0 Å. Three slit sets, a secondary photon shutter, two beam monitors, filters and absorbers, a multi-sample holder, a vacuum path, a beam-stopper and a set of detectors are the basic components of the workstation. The stepping motors are equipped with specially designed encoders. All mechanical and pneumatic movements and detectors can be remotely controlled using a direct panel or a PC.

This report summarizes XAFS investigations, particularly in the XANES region, performed to date on a variety of materials containing Si, Al and Mg using a double-crystal YB 66 monochromator in the 1-2 keV region.

'Summaro form only given. A Cellular Neural Network (CNN) computational scheme is a processor array structure that emulates the most valuable parallelizing capabilities of the Artificial Neural Network (ANN) (L. Chua, L. Yang, Circuits and Systems, IEEE Tran, 1988). Each cell or processor inside the array has a specific processing capabilities depending on the mapped numerical application over it. This scheme has been proved in different applications that assure a PDE regular mesh mapping (A. Kiss, Z. Nagy, Journal of Circuit Theory and App, 2008).

A long standing theoretical problem ``the absence of a white line in the ${L}_{2}$ x-ray absorption near edge spectrum of Pt metal'' has been solved taking into account relativistic effects and the presence of a core hole. The photoabsorbing atom is treated as a single-site impurity in our theory of x-ray absorption near edge structure (XANES) based on the fully relativistic layer Korringa-Kohn-Rostoker Green-function method. Comparing the XANES of Al with those of Cu and Pt, it is found that for transition metals $d$ electrons play a dominant role in deep core-hole screening, whereas in Al $\mathrm{sp}$ electrons are important.

We have helped to develop novel synchrotron‐radiation‐based techniques, using circularly polarized x rays. Photoelectron spectroscopy, photoelectron diffraction, and x‐ray absorption variants will be discussed. From these, we are working to establish the structure–property relationships in nanoscale magnetic systems.

A fully relativistic Green function formalism is applied to calculate the layer-, k/sub ///- and double group symmetry-resolved densities of states (DOS) and the spin-resolved normal photoemission intensities produced by normally incident circularly polarized light for the (001) surface of Cu3Au in its ordered phase. In the calculated photoemission spectra, a number of features can be ascribed to interband transitions in the authors simultaneously calculated bulk band structure, with a real self-energy correction of -0.45 eV for the lower and of 2.5 eV for the upper states. In addition, the authors identify seven features as due to surface states or surface resonances. A comparison with spin-resolved experimental data shows reasonable agreement with regard to existence, energy and preferential spin polarization (i.e. symmetry type of initial states) for most features.

To study the electronic structure of ferromagnetic crystalline compounds, their surfaces and adsorbed ultrathin films, a fully relativistic Green function formalism has been developed. For a semi-infinite system, which is described by a complex effective potential the single-particle Green function and thence the layer-, k/sub ///- and spin- or symmetry-resolved densities of states-at the surface and in the bulk-are obtained using a layer Korringa-Kohn-Rostoker method. This Green function-for quasi-hole states-is employed in a relativistic one-step model formalism to yield spin- and angle-resolved photoemission intensities.

A strong enhancement of the angle-resolved photocurrent, which was observed for many metals at special ultraviolet photon energies, is understood as a consequence of competing direct transitions coupled by electron-hole scattering. This mechanism is formally described by a many-body Keldysh diagram, in which one photon vertex is renormalized by a screened Coulomb interaction. Numerical evaluation within a three-step-model approximation leads to good agreement with experimental data for Pd(111).

Photoelectrons emitted normal to (001) surfaces of nonmagnetic centrosymmetric cubic crystals by off-normally incident linearly and unpolarized light are spin polarized. From symmetry, the polarization is perpendicular to the incidence plane and its size has no azimuthal dependence. As is seen analytically, the effect is due to the spin-orbit-induced hybridization of basis functions of different spatial symmetry types. Relativistic one-step-model multiple scattering calculations for Pt(001) and Pd(001) predict large polarization features depending sensitively on the top layer spacing.

In normal photoemission from (1 1 1) surfaces of non-magnetic centro- symmetric cubic crystals by off-normally incident linearly and unpolarized light, spin-orbit coupling produces two different spin polarization effects. One, which already occurs for normal incidence, arises from half-space initial states of double group symmetry Λ 4+5 . The other comes from Λ 6 states and reflects the hybridization of basis functions of spatial symmetries Λ 1 and Λ 3 . For a special azimuthal angle of photon incidence the two surface-parallel spin polarization vectors are perpendicular to each other. Relativistic dynamical calculations for Pt(1 1 1) reveal large polarization features, which are sensitive to the surface barrier.

A relativistic Green function formalism has been applied to calculate layer-projected densities of states on Pd(110). In particular, we obtained unoccupied surface states and their dispersion relations along two directions in the surface Brillouin zone. Good agreement with recent inverse photoemission data is reached by using an energy-dependent “dynamical” surface potential barrier, which is based on a simple electron-plasmon interaction model, instead of a “static” surface barrier.

Exchange and spin-orbit scattering asymmetries of spin-polarized low-polarized low-energy electrons from Fe(110) are measured at room temperature for several beams at constant energies as functions of the polar angle of incidence (“rocking curves”). Corresponding calculations by means of a relativistic multiple scattering formalism gave results in good agreement with the experimental data. The sensitivity of part of the calculated curves to changes in the layer magnetization implies an enhancement of the topmost layer magnetization by about 36 to 40% relative to the bulk and possibly a reduction in the second layer. Further, a dominance of spin-down over spin-up inelastic scattering is deduced associated with 3p 3d excitation. Die durch Austauschwechselwirkung und Spinbahnkopplung bedingten Streuasymmetrien bei der Beugung langsamer Elektronen an Fe(110) werden bei Zimmertemperatur fur verschiedene Strahlen bei konstanter Energie als Funktionen des polaren Einfallswinkels gemessen. Entsprechende Rechnungen mittels eines relativistischen Vielfachstreuformalismus liefern Ergebnisse in guter Ubereinstimmung mit den experimentellen Daten. Aus der Empfindlichkeit von Teilen der berechneten Kurven gegenuber Anderungen der schichtabhangigen Magnetisierung folgt eine Erhohung der Magnetisierung der obersten Schicht um ca. 36 bis 40% relativ zum Volumenwert und moglicherweise eine Verringerung in der zweiten Schicht. Auserdem folgt, das bei der 3p 3d-Anregung Minoritatselektronen starker inelastisch gestreut werden als Majoritatselektronen.

The magnetic polarization of delocalized Cu electrons in the layered $\mathrm{Co}∕\mathrm{Cu}$ structures and the exchange coupling energy of ferromagnetic Co moments across the Cu spacer have been calculated using the quantum-interference model. The quantum-well term of the total Cu spin moment oscillates versus the spacer thickness with a phase retarded by about $\ensuremath{\pi}∕2$ from the coupling energy. This phase relation has been evidenced experimentally by measuring x-ray magnetic circular dichroic (XMCD) absorptions at the Co and Cu $K$ edges from a series of $\mathrm{Co}∕\mathrm{Cu}$ multilayers with varying Cu thicknesses. The normalized Cu XMCD signals show a larger modulation as a function of Cu-layer thickness than predicted by the quantum-well term of the total Cu moment. The interface term makes marginal contributions to the total Cu moment probably because of the detrimental effects of rough interfaces in the sputter-deposited $\mathrm{Co}∕\mathrm{Cu}$ multilayers.

Locking caches, providing full determinism and good performance, are a very interesting solution to replacing conventional caches in real-time systems. In such systems, temporal correctness must be guaranteed. The use of predictable components, like locking caches, helps the system designer to determine if all the tasks will meet its deadlines. However, when locking caches are used in a static manner, the system performance depends on the instructions loaded and locked in cache. The selection of these instructions may be accomplished through a genetic algorithm.

Cache memories are crucial to obtain high performance on contemporary processors. However, they have been traditionally avoided in embedded real-time systems due to their lack of determinism. Unfortunately, most of the techniques to attain predictability on caches are complex to apply, precluding their use on real applications. This work reviews several techniques developed by the authors to use cache memories in “real” embedded real-time systems, with the ease of use in mind. Those techniques are based on a locking cache, which offers a very predictable behaviour. Both static and dynamic use are proposed as well as the algorithms and methods required to make the schedulability analysis using two different scheduling policies. Also proposed is a genetic algorithm that finds, within acceptable computational cost, the sub-optimal set of instructions that must be preloaded in cache. Finally, a set of statistical analyses compares the locking cache versus a conventional one.

The tunnel magnetoresistance effect (TMR), which is intrinsically determined by the interface monolayer of an electrode, was realized by using magnetic tunnel junctions (MTJs) with a single-crystal Cr(001) layer inserted between a tunnel barrier and an electrode. The MTJs showed an oscillation of the TMR ratio as a function of the thickness of the Cr(001) layer with a period of 2 monatomic layers, which corresponds to the layered antiferromagnetic structure of Cr(001). These oscillations originate from electron scattering at the interface, due to the mismatching of the symmetry of the wave functions and band structure in Cr(001).

This study aims to treat locally-advanced nasopharyngeal cancer by concurrent conventional irradiation at 2.0 Gy/day five days per week up to a total dose of 68 Gy, and daily intra-arterial infusion of cisplatin 3 mg/m2 plus 24 hours intravenous drip infusion of 5-fluorouracil 150 mg/m2 per day, five days per week. All of five enrolled patients completed the schedule, and treatment compliance was considered to be identical. Of the five patients evaluable for response, four with complete response (80%) and one with partial response (20%), with an overall response rate of 100% was achieved. The median survival time was 26 months. Two-year survival of the patients was 80%. This regimen showed marginal mucositis but well tolerated. We concluded that this treatment option is safe and effective for the locally-advanced nasopharyngeal cancer.

An experimental system comprising a parallel-link manipulator based on a newly proposed singularity-perturbed design of the planar five-bar linkage is described. Experiments are carried out for end-point path tracking control along a path passing through both an undermobility and an overmobility type singularity and the experimental data analysis is presented.

The influence of steps on the surface states of the magnetic Fe(001) surface was studied at room temperature by scanning tunneling microscopy (STM). We observed the distinct bias-dependent differential conductivity $(dI/dV)$ contrasts at step edges from those on flat terraces. The observed $dI/dV$ line profiles across the step edge exhibit the strong reduction of the empty-state local density of states up to 1 eV above the Fermi level. That can be attributed to the scattering of the minority-spin surface states by the step edge, thus, a sizable spin-dependent contrast at the step edge is predicted in spin-polarized STM.

To improve survival rate in advanced head and neck cancer, we scheduled 90 patients to receive low dose cisplatin plus 5-fluorouracil regimen as neoadjuvant(NAC), concurrent(CC), adjuvant(AC), and second line chemotherapy (SC) setting. Our regimen consisted of cisplatin (CDDP 5 mg/m2/1 hr infusion on days 1-5, 8-12, 15-19, 22-26) and 5-fluorouracil (5-FU 200 mg/m2/24 hr infusion or oral administration of tegaful-uracil (UFT-E) 400 mg/body on days 1-28). The concurrent chemoradiotherapy consisted of conventional irradiation with 1.6-2.0 Gy/day on five days per week up to a total dose around 60Gy, and CDDP 3 mg/m2 by intravenous infusion over 1 hour plus 5-FU 150 mg/m2 by intravenous infusion over 24 hours per day on five days per week. For SC, 24 patients evaluable for response, 4 CR and 6 PR with RR of 42% were achieved. For NAC, 14 patients were evaluated for response, 2 CR and 7 PR were achieved. CC was indicated for locally unresectable cases. Of the 33 patients evaluable for response were 17 CR and 9 PR with RR of 79%. Dose limiting toxicities for chemotherapy were anemia and leukopenia and chemoradiotherapy was mucositis. Our treatment modality showed marginal toxicity and good response. Moreover, our regimen could be given in an outpatient setting safely so quality of life for patients was identical. We concluded that for advanced head and neck cancer, these treatment options were effective for second line and adjuvant setting. Chemoradiotherapy with this regimen also gave a impact for improving local control and survival period for locally unresectable cases.

Synchrotron anomalous X-ray scattering confirmed that Re distribution on the Hg–O plane did not produce a super cell (2 a × 2 b × 1 c ) in our Hg 0.8 Re 0.2 Ba 2 Ca 2 Cu 3 O 8.7+ d samples. Moreover, even for a high quality sample (highest T c and single phase diamagnetic transition), the synchrotron X-ray diffraction pattern analyzed by Rietveld refinement confirms there exist two superconducting phases present in the sample produced with optimal oxygen doping content (Hg-1223 and Hg,Re-1223). The non-existence of (2 a × 2 b × 1 c ) super cell can justify the scenario where charge inhomogeneities distribution are present in the outer CuO 2 layers.

Preliminary measurements in a proportional counter with two independently counting wires showed that counting rates up to 106 counts s−1 wire−1 can be reached without critical loss in the `true versus measured' linearity relation. Results obtained with a detector containing 30 active wires (2 mm pitch) are presented. With each wire is associated a fast pre-amplifier and a discriminator channel. Global counting rates in excess of 107 events s−1 are reported. Dead-time losses are corrected by use of simple mathematical-modelling functions. Data-acquisition systems are described for one-dimensional (real-time) and two-dimensional (off-line) position-sensitive detection systems.

Until recently x-ray absorption fine structure (XAFS) measurements in the 1-2 keV region remained a challenging experimental task. This was primarily due to the lack of an adequate monochromator crystal that possessed both the required x-ray properties (large d-spacing, high resolution and reflectivity) and materials properties (ultra-high vacuum (UHV) capability, damage resistance in a synchrotron radiation beam, absence of constituent element absorption edges and stability, both thermal and mechanical). Traditionally, XAFS spectra in this photon energy range have been measured in a piece-wise fashion using a combination of monochromator crystals. Very recently, we have an experimental breakthrough in XAFS spectroscopy in this soft x-ray region. This energy region is of great importance for materials and basic research since the K-edges of Na (1070 eV), Mg (1303 eV), Al (1557 eV) and Si (1839 eV), the L-edges of some 4p elements from Ga to Sr and the M-edges of the rare-earth elements fall within this energy window of the electromagnetic spectrum. YB{sub 66}, a complex binary semiconducting yttrium boride having a cubic crystal structure with a lattice constant of 23.44 {angstrom} has been singled out as a candidate monochromator material for synchrotron radiation in the 1-2 keV region. There is no intrinsic absorption by the constituent elements in this region, which can adequately be dispersed by the (400) reflection having a 2d value of 11.76 {angstrom}. In terms of vacuum compatibility, resistance to radiation damage, thermal and mechanical stability, YB{sub 66} satisfies all the material requirements for use as a monochromator in a synchrotron beam. In the past few years, LLNL in collaboration with a number of other research institutes has pioneered the development of this unique man-made crystal for use as soft x-ray monochromator with synchrotron light sources for materials science studies. 23 refs., 4 figs.

Using a recently developed spin-polarized, fully relativistic, multiple scattering approach based on the layer Korringa-Kohn-Rostoker Green function method, we have reproduced the Fe $3p$ angle resolved soft x-ray photoemission spectra and analyzed the associated large magnetic dichroism effects for excitation with both linearly and circularly polarized light. Comparison between theory and experiment yields a spin-orbit splitting of 1.0-1.2 eV and an exchange splitting of 0.9-1.0 eV for Fe $3p$. These values are 50%-100% larger than those hitherto obtained experimentally.

Using a recently developed spin-polarized, fully relativistic, multiple scattering approach based on the layer KKR Green function method, we have reproduced the Fe 3p angle-resolved soft x-ray photoemission spectra and analyzed the associated large magnetic dichroism effects for excitation with both linearly and circularly polarized light. Comparison between theory and experiment yields a spin-orbit splitting of 1.0 – 1.2 eV and an exchange splitting of 0.9 – 1.0 eV for Fe 3p. These values are 50 – 100 % larger than those hitherto obtained experimentally.

A fully relativistic layer-KKR formalism was developed and implemented for calculating the single-particle Green function in atomic layers parallel to crystalline surfaces magnetic and non magnetic materials: The method was applied to the calculation surface spectroscopies, such as low energy electron diffraction (LEED), angle-resolve ultraviolet photo emission spectroscopy (UPS), and photoelectron scattering. Numeric tests were performed for non magnetic actinide surfaces and magnetic Fe surface Theoretical angle-resolved UPS spectra are presented for uranium monolayers on Pt(111) and for f.c.c. u(lll) surfaces. We find that u island formation can take place if a peak in the UPS spectra appears just before the Fermi energy immediately as u is deposited on P and we suggest an experimental procedure for testing this prediction. An intensity map photo excited electrons from the 2p{sub 3/2} core states of Fe(110) surface is also show Sizable magnetic anisotropy is found due to the interference between exchange and spin-orbit interaction, which is suitable for studying a possible surface-induced magnetism actinide adlayers.

Spin-resolved photoemission spectra from solid Xe(111) have been measured using circularly polarized synchrotron radiation with photon energies ranging from 11-18 eV. Corresponding calculations by a fully relativistic one-step-model layer KKR formalism produce fairly good agreement with the experimental data. The spectra can be interpreted in terms of direct interband transitions in the real part of a complex-potential band structure. This provides detailed information on the quasi-particle band structure including real and imaginary self-energy corrections to the valence and conduction bands. Observed 'opposite-spin features', which are absent in the calculated spectra, are tentatively interpreted as due to electron-hole scattering processes.