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Using grazing-incidence x-ray diffraction and scanning tunneling microscopy (STM), we show that the thermal decomposition of an electronic-grade wafer of 6H-SiC after annealing at increasing temperatures T[sub A] between 1080 and 1320 °C leads to the layer-by-layer growth of unconstrained, heteroepitaxial single-crystalline graphite. The limited width of the in-plane diffraction rod profiles of graphite reveals large terraces, with an average size larger than 200 Å and a very small azimuthal disorientation. The overlayer is unstrained and adopts the crystalline parameter of bulk graphite even at the smallest coverage studied, which corresponds to a single graphene plane, as inferred from the flat out-of-plane diffraction profile. By increasing T[sub A], additional graphene planes can be grown below this graphite layer from the solid-state decomposition of SiC, forming the AB stacking of Bemal graphite. A C-rich precursor is evidenced in STM by an intrinsic (6 × 6) reconstruction made of ordered ring or starlike structures. The resulting epitaxial film is indistinguishable from a bulk graphite single crystal. [ABSTRACT FROM AUTHOR]

Background: Claudin-18 (CLDN18) is a highly specific tight junction protein of the gastric mucosa. An isoform of CLDN18, the Claudin 18.2, has recently emerged as an innovative drug target for metastatic gastric cancer.Methods: We investigated the immunohistochemical profile of CLDN18, p53, p16, E-cadherin, MSH2, MSH6, MLH1, PSM2, HER2, and PDL-1 in a large series of 523 primary gastric carcinomas (GCs; n = 408) and gastro-oesophageal carcinomas (GECs; n = 115) and 135 matched and synchronous nodal metastases. The status of HER2 and EBER by means of chromogenic in situ hybridisation (CISH) was also evaluated.Results: High membranous CLDN18 expression was present in 150/510 (29.4%) primary cases and in 45/132 (34.1%) metastases. An abnormal expression (i.e. nuclear and/or cytoplasmic) was observed in 115 (22.5%) primary cases and in 33 (25.0%) metastases. A 38.8% of the cases showed significant CLDN18 intratumoural variability among the different tissue microarray cores obtained from the same tumour. Positive membrane CLDN18 expression was statistically associated with non-antral GCs (p = 0.016), Lauren diffuse type (p = 0.009), and with EBV-associated cancers (p < 0.001).Conclusions: CLDN18 is frequently expressed in gastric and gastro-oesophageal cancers; further studies should investigate the prognostic significance of CLDN18 heterogeneity in order to implement its test into clinical practice. [ABSTRACT FROM AUTHOR]

Merkel cell carcinoma (MCC) is a rare, aggressive primary cutaneous neuroendocrine carcinoma. It usually appears on the face and neck of elderly Caucasian people as a flesh-colored, erythematous or violaceous dome-shaped, non-tender nodule with a smooth surface. In immunocompromised patients with T-cell dysfunction, such as patients with acquired immunodeficiency syndrome (AIDS) or solid organ transplant recipients, the incidence of this disease is markedly increased. This suggests a link between the development of MCC and the immune system. Merkel cell polyolmavirus (MCPyV) is clonally integrated into the majority of MCCs, suggesting its causative role in the pathogenesis of the majority of these tumors. Despite wide local excision, sentinel lymph node biopsy and eventually, adjuvant radiation therapy, which remains the first-line treatment for MCC, the identification of MCPyV has opened novel therapeutic insights. Novel therapeutic strategies could be to inhibit MCPyV oncoproteins and to stimulate immune responses against virus-infected tumor cells by immunostimulatory cytokines, including interferons and interleukin-2. [ABSTRACT FROM AUTHOR]

Innate immune cells recognize highly conserved pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs). Previous studies have demonstrated that PRRs also recognize endogenous molecules, termed damage-associated molecular patterns (DAMPs) that are derived from damaged cells. PRRs include Toll-like receptors (TLRs), scavenger receptors, C-type lectin receptors and nucleotide oligomerization domain-like receptors. To date, 10 TLRs have been identified in humans and each receptor responds to a different ligand. The recognition of PAMPS or DAMPs by TLRs leads to the activation of signaling pathways and cellular responses with subsequent pro-inflammatory cytokine release, phagocytosis and antigen presentation. In the human skin, TLRs are expressed by keratinocytes and melanocytes: The main cells from which skin cancers arise. TLRs 1-6 and 9 are expressed in keratinocytes, while TLRs 2-5, 7, 9 and 10 have been identified in melanocytes. It is hypothesized that TLRs may present a target for melanoma therapies. In this review, the involvement of TLRs in the pathogenesis and treatment of melanoma was discussed. [ABSTRACT FROM AUTHOR]

Ultra-thin Ag/Ni(111) reconstructed interfaces have been revisited by a combination of in-situ grazing incidence x-ray diffraction (GIXD) and x-ray photoelectron diffraction (XPD) in order to determine the growth mode and to evaluate the interface spacing. Evidence for predominance of single-layer growth in the early stages was obtained through the analysis of the x-ray diffraction rods from the Ag/Ni(111) (√52 x √52)R13.9° reconstructed interlace, whereas photoelectron diffraction patterns could reveal traces of second-layer Ag scatterers before full wetting of the substrate. Refinement of the atomic coordinates provided by quenched molecular dynamics simulation on the basis of the new x-ray data set enabled us to assess the Ag/Ni average interplanar distance, which was lbund unexpanded at 2.44 ± 0.07 Å, in contrast with recent determination by low-energy electron diffraction and microscopy. For increasing deposited amounts, both GIXD and XPD showed the expected features of two- and three-layer silver epitaxial overgrowths. [ABSTRACT FROM AUTHOR]

Abstract: The first stages of growth and organisation of a silver atom deposit on a nickel (111) surface have been investigated by scanning tunnelling microscopy. For a coverage lower than two monolayers and depending on the surface defect content, deposition at room temperature leads to a random distribution of small Ag islands on the surface, while growth at 400K shows the Ag trend to form islands mainly attached to the substrate step edges. When the sample is annealed at 525K, Ag organises in stripes decorating the steps edges and in islands located in the middle of the large terraces, with a thickness of one or two monolayers. Further annealing at 675K completely reorganises the surface morphology with a strong demixing: Ag uniformly covers part of the substrate terraces, and leaves large bare Ni areas. At this stage, the ultra-thin film always presents a thickness of two monolayers. [Copyright &y& Elsevier]

It is demonstrated that grazing-incidence X-ray diffraction is a direct tool for measuring the elastic displacement modes near the surface of a crystal. Due to the fact that X-ray diffraction is a Fourier transform of the electronic density, and thus, of the atomic positions, elastic displacement modes appear as additional spots in the reciprocal space. Their characteristics can be directly derived from the elastic constants of the material. Measuring the amplitude of the diffracted wave for these peaks allows direct determination of the force distribution at the surface, which is at the origin of the elastic displacements. Various examples of such determinations are given for self-organized surfaces and for vicinal surfaces. [ABSTRACT FROM AUTHOR]

In this work we investigate the diffusion and precipitation of supersaturated substitutional carbon in 200-nmthick SiGeC layers buried under a silicon cap layer of 40 nm. The samples were annealed in either inert (N[sub 2]) or oxidizing (O[sub 2]) ambient at 850 °C for times ranging from 2 to 10 h. The silicon self-interstitial (I) flux coming from the surface under oxidation enhances the C diffusion with respect to the N[sub 2]-annealed samples. In the early stages of the oxidation process, the loss of C from the SiGeC layer by diffusion across the layer/cap interface dominates. This phenomenon samrates after an initial period (2-4 h), which depends on the C concentration. This saturation is due to the formation and growth of C-containing precipitates that are promoted by the I injection and act as a sink for mobile C atoms. The influence of carbon concentration on the competition between precipitation and diffusion is discussed. [ABSTRACT FROM AUTHOR]

A method for completely suppressing the transient enhanced diffusion (TED) of boron implanted in preamorphized silicon is demonstrated. Boron is implanted in a molecular beam epitaxy (MBE) grown silicon sample that has been previously amorphized by silicon implantation. The sample is then annealed in order to epitaxially regrow the amorphous layer and electrically activate the dopant. The backflow of silicon interstitials released by the preamorphization end-of-range (EOR) damage is completely trapped by a carbon-rich silicon layer interposed by MBE between the damage and the implanted boron. No appreciable TED is observed in the samples up to complete dissolution of the EOR damage, and complete electrical activation is obtained. The method might be considered for the realization of ultrashallow junctions for the far future complementary metal-oxide-semiconductor technology nodes. © 2001 American Institute of Physics. [DOI: 10.1063/1.1425458]. [ABSTRACT FROM AUTHOR]

The administration of cyproterone acetate (CPA) and estradiol is a common regimen used by male-to-female transsexuals (transwoman) to adjust their body to their gender identity. Major adverse events are uncommon in these subjects in spite of long-term, high dose cross-sex steroid treatments. We describe the occurrence of a meningioma in a transwoman treated with estrogens and CPA over a period of nine years. The meningioma was revealed during a magnetic resonance imaging (MRI) scan performed as follow-up of a previous surgery for ganglioglioma. CPA intake was discontinued and tumor resection was performed. Histological diagnosis confirmed a strong progesterone receptor-positive and slight estrogen positive meningioma. After surgery, the patient continued her treatment with leuprorelina acetate and estradiol. At one-year follow-up, the MRI scan reveals no recurrence of the tumor. This is the ninth case in literature of a meningioma in a transwoman treated with estrogens and CPA, confirming a possible association between female sex steroids and meningioma. Although there is no still strong evidence of an association between meningioma and CPA, this report may suggest use of alternative treatment for transwomen. This report highlights the importance to record all the cases of meningiomas in high dose CPA-users, in order to improve data. [ABSTRACT FROM AUTHOR]

Positive surgical margins (PSMs) in radical prostatectomy specimens are usually considered a negative prognostic parameter . However, their definition and the management of patients with PSMs remain unclear . The aim of the present review is to define pathological features of PSMs, to report their incidence and risk factors and to update PSMs prognostic meaning and possible treatment modalities. The average incidence of PSMs in contemporary series ranges from 6.5% to 32%. The likelihood of PSMs is influenced by pre-operative PSA (total-PSA and PSA-density), tumor features (volume, grade and stage), previous prostatic surgery (open or TURP), patients' characteristics (BMI and pelvis shape) and surgeons' skill. Although PSMs are a predictor of biochemical recurrence, their impact on cause specific survival is highly variable and largely influenced by the tumor Gleason Score. Adjuvant radiotherapy is an effective treatment in PSMs patients but early salvage radiotherapy may be an alternative option that guarantees equivalent survival benefits with less side effects. Further studies are required to define the best candidates to adjuvant or early salvage radiation therapy. [ABSTRACT FROM AUTHOR]

The pharmacokinetics of the novel cephalosporin cefovecin were investigated in a series of in vivo, ex vivo and in vitro studies following administration to adult cats at 8 mg/kg bodyweight. Bioavailability and pharmacokinetic parameters were determined in a cross-over study after intravenous (i.v.) and subcutaneous (s.c.) injections. [14C]cefovecin was used to evaluate excretion for 21 days after s.c. administration. Protein binding was determined in vitro in feline plasma and ex vivo in transudate from cats surgically implanted with tissue chambers. After s.c. administration, cefovecin was characterized by rapid absorption with mean peak plasma concentrations of 141 ± 12 μg/mL being achieved within 2 h of s.c. injection with full bioavailability (99%). The mean elimination half-life was 166 ± 18 h. After i.v. administration, volume of distribution was 0.09 ± 0.01 L/kg and mean plasma clearance was 0.35 ± 0.04 mL/h/kg. Approximately 50% of the administered radiolabelled dose was eliminated over the 21-day postdose period via urinary excretion and up to approximately 25% in faeces. In vitro and ex vivo plasma protein binding ranged from 99.8% to 99.5% over the plasma concentration range 10–100 μg/mL. Ex vivo protein binding in transudate was as low as 90.7%. From 8 h postdose, concentrations of unbound (free) cefovecin in transudate were consistently higher than in plasma, with mean unbound cefovecin concentrations being maintained above 0.06 μg/mL ( MIC90 of Pasteurella multocida) in transudate for at least 14 days postdose. The slow elimination and long-lasting free concentrations in extracellular fluid are desirable pharmacokinetic attributes for an antimicrobial with a 14-day dosing interval. [ABSTRACT FROM AUTHOR]

It is shown that information on the spatial correlation of nano‐objects embedded in a crystalline matrix can be retrieved by analysing the X‐ray scattering around the Bragg reflections of the host matrix. Data are reported for vertically aligned Ni and CoNi alloy nanowires (NWs) in an SrTiO3 matrix. When the Bragg condition is fulfilled for the matrix and not for the NWs, the latter can be approximated by voids, and the scattering around the matrix reflections contains information on the self‐correlation of the NWs (i.e. on their diameter d) and on the correlation between NWs (interdistance D). Nondestructive synchrotron X‐ray diffraction data provide information on these values averaged over large areas, complementing local transmission electron microscopy observations. The measurements show that off‐Bragg scattering around the matrix reflections can be exploited to study the spatial correlation and morphology of embedded nano‐objects, independently of their crystallinity or strain or the presence of defects. [ABSTRACT FROM AUTHOR]

The rocksalt‐type ferromagnetic (FM) insulator EuS (bulk TC = 17 K) grown on Bi2Se3 with well‐matched (111) plane of the film and (0001) plane of the substrate is studied. The system may feature magnetic proximity effect breaking the time‐reversal symmetry and opening a bandgap in the metallic topologically protected surface state of Bi2Se3. The experimental X‐ray diffraction studies are combined with ab initio calculations to resolve contradictory results concerning the enhancement of the TC up to 300 K and the degree of induced magnetization in the system. It is concluded that previous studies relied on idealized and unconfirmed structure models. Herein, it is shown by surface X‐ray diffraction (SXRD) with ab initio calculations that a two double layer‐thick EuS film grows with a sharp interface and without chemical intermixing in a single domain state in an FCC‐type stacking on the Bi2Se3(0001) surface in which the topmost layer is metallic, thereby lifting polarity. A large pz‐orbital‐derived top‐layer sulfur magnetic moment of 0.6 μB is found, whereas for europium, μEu = 6.9 μB throughout the film is found. No magnetization within the first Bi2Se3 quintuple layer is found. The calculation of the exchange parameters Jij indicates a complex FM and antiferromagnetic ordering between europium and sulfur with a maximum Néel temperature of 226 K. [ABSTRACT FROM AUTHOR]

We explore the use of continuous scanning during data acquisition for Bragg coherent diffraction imaging, i.e., where the sample is in continuous motion. The fidelity of continuous scanning Bragg coherent diffraction imaging is demonstrated on a single Pt nanoparticle in a flow reactor at 400 ∘ C in an Ar-based gas flowed at 50 ml/min. We show a reduction of 30% in total scan time compared to conventional step-by-step scanning. The reconstructed Bragg electron density, phase, displacement and strain fields are in excellent agreement with the results obtained from conventional step-by-step scanning. Continuous scanning will allow to minimise sample instability under the beam and will become increasingly important at diffraction-limited storage ring light sources. [ABSTRACT FROM AUTHOR]

Kirkendall effect has played an important role in developing the understanding of atomic diffusion and mass transport in solids. In thin films and multilayers, in which the microstructure may be far from thermal equilibrium, behavior of a system can be very different from that of the bulk. Therefore, there is a great need to understand the peculiarities of Kirkendall shift occurring at nanometer or sub-nanometer length scale in such systems. In the present work, Kirkendall shift in thin films has been measured with sub-nanometer accuracy, by making use of x-ray planar waveguide structures. Using this technique, we report an apparently counterintuitive result of Kirkendall shift associated with self-diffusion in nanocrystalline iron. The cavity of the waveguide consists of two layers of iron having different microstructures, separated by a thin marker layer of Ag. Thermal annealing results in shift of the Ag marker towards the Fe layer having a coarser grain structure. The effect is established unambiguously by studying two samples with the order of the two Fe layers reversed, and a third sample with the two Fe layers having the same microstructure. The result can be understood in terms of the difference in the microstructure of the two Fe layers; difference in the grain size and hence different concentration of the grain boundaries in the two layers results in a net mass transfer from one region to the other. [Display omitted] [ABSTRACT FROM AUTHOR]

Objectives: Gastritis OLGA-staging ranks the risk for gastric cancer (GC) in progressive stages (0-IV). This long-term follow-up study quantifies the GC risk associated with each OLGA stage.Methods: Consecutive patients (7436) underwent esophagogastroscopy (T-0), with mapped gastric biopsies, OLGA staging, and H. pylori status assessment. Patients with neoplastic lesion (invasive or non-invasive) at the index endoscopy (and/or within 12 months) were excluded. All patients were followed-up (T-1) by combining different sources of clinical/pathological information (Regional Registries of: (i) esophagogastroduodenoscopies; (ii) pathology reports; (iii) cancer, (iv) mortality). The endpoint was histologically documented development of gastric epithelial neoplasia.Results: At T-0, the patients’ distribution by OLGA stage was: Stage 0 = 80.8%; Stage I = 12.6%; Stage II = 4.3%; Stage III = 2.0%; Stage IV = 0.3%; H. pylori infection was detected in 25.9% of patients. At the end of the follow-up (mean/median = 6.3/6.6 years), 28 incident neoplasia were documented (overall prevalence = 0.60 per 103/person-years; low-grade intraepithelial neoplasia = 17/28; high-grade intraepithelial neoplasia = 4/28; GC = 7/28). By OLGA stage at the enrollment, the rate of incident neoplasia was: Stage 0 = 1 case; rate/103 person-years = 0.03; 95%CI: 0.004-0.19; Stage I = 2 cases; rate/103 person-years = 0.34; 95%CI: 0.09-1.36; Stage II = 3 cases; rate/103 person-years = 1.48; 95%CI: 0.48-4.58; Stage III = 17 cases; rate/103 person-years = 19.1; 95%CI: 11.9-30.7; Stage IV = 5 cases; rate/103 person-years = 41.2; 95%CI: 17.2-99.3. Multivariate analysis including gender, age, H. pylori status, and OLGA stage at enrollment only disclosed OLGA stage as predictor of neoplastic progression (OLGA stage III: HR = 712.4, 95%CI = 92.543-5484.5; OLGA stage IV: HR = 1450.7, 95%CI = 166.7-12626.0).Conclusions: Among 7436 patients, OLGA stages at the enrollment correlated significantly with different risk for gastric neoplasia. Based on the obtained results, gastritis staging is a critical adjunct in endoscopy follow-up protocols aimed at GC secondary prevention. [ABSTRACT FROM AUTHOR]

We report the successful use of in situ grazing incidence small-angle X-ray scattering to follow the anodization of aluminum. A dedicated electrochemical cell was designed and developed for this purpose with low X-ray absorption, with the possibility to access all azimuthal angles (360°) and to remotely control the temperature of the electrolyte. Three well-known fabrication techniques of nanoporous alumina, i.e., single, double, and pretextured, were investigated. The differences in the evolution of the scattering images are described and explained. From these measurements, we could determine at which moment the pores start growing even for very short anodization times. Furthermore, we could follow the thickness of the alumina layer as a function of the anodization time by monitoring the period of the Kiessig fringes. This work is aimed at helping to understand the different steps taking place during the anodization of aluminum at the very early stages of nanoporous alumina formation. [ABSTRACT FROM AUTHOR]

Objectives: To test miR-223 upregulation during gastric (intestinal-type) and Barrett esophageal carcinogenesis.Methods: miR-223 expression was assessed by quantitative reverse transcription polymerase chain reaction in a series of 280 gastroesophageal biopsy samples representative of the whole spectrum of phenotypic changes involved in both carcinogenetic cascades. The results were further validated by in situ hybridization on multiple tissue specimens obtained from six surgically treated gastroesophageal adenocarcinomas. miR-223 expression was also assessed in plasma samples from 30 patients with early stage (ie, stages I and II) gastroesophageal adenocarcinoma and relative controls.Results: In both gastric and esophageal models, miR-223 expression significantly increased along with the severity of the considered lesions (analysis of variance, P  <   .001). Among atrophic gastritis and long-segment Barrett esophagus samples, miR-223 overexpression was significantly associated with the score of intestinal metaplasia. miR-223 plasma levels were significantly upregulated in patients with cancer compared with controls ( t test, both P  <   .001).Conclusions: miR-223 early upregulation observed in tissue samples and its diagnostic value in discriminating patients with early adenocarcinoma by plasma testing provide a solid rationale for further exploring the diagnostic reliability of this microRNA as a novel biomarker in gastroesophageal adenocarcinoma secondary prevention strategies. [ABSTRACT FROM AUTHOR]

Producing a usable semiconducting form of graphene has plagued the development of graphene electronics for nearly two decades. Now that new preparation methods have become available, graphene's intrinsic properties can be measured and the search for semiconducting graphene has begun to produce results. This is the case of the first graphene "buffer" layer grown on SiC(0001) presented in this work. We show, contrary to assumptions of the last 40 years, that the buffer graphene layer is not commensurate with SiC. The new modulated structure we've found resolves a long-standing contradiction where ab initio calculations expect a metallic buffer, while experimentally it is found to be a semiconductor. Model calculations using the new incommensurate structure show that the semiconducting π-band character of the buffer comes from partially hybridized graphene incommensurate boundaries surrounding unperturbed graphene islands. [ABSTRACT FROM AUTHOR]

The growth by pulsed laser deposition of fully epitaxial nanocomposites made of CoxNi1–x nanowires (NW) vertically self-assembled in Sr0.5Ba0.5TiO3/SrTiO3(001) layers is reported. The diameter of the wires can be tuned in the 1.8–6 nm range. The composition of the wires can be controlled, with the growth sequence and the fcc crystallographic structure of the wires preserved for Co content up to 78%. The nanocomposite systems obtained display a uniaxial magnetic anisotropy with out-of-plane easy axis as shown through analysis of ferromagnetic resonance measurements. It is shown that the magnitude of the magnetic anisotropy depends sensitively on the structural quality of the nanocomposites.The energy barrier for magnetization reversal scales as the square of the diameter of the NW and reaches 60 for 6 nm diameter, with Tamb = 300 K. [ABSTRACT FROM AUTHOR]

We report the design of a mobile setup for synchrotron based in situ studies during atomic layer processing. The system was designed to facilitate in situ grazing incidence small angle x-ray scattering (GISAXS), x-ray fluorescence (XRF), and x-ray absorption spectroscopy measurements at synchrotron facilities. The setup consists of a compact high vacuum pump-type reactor for atomic layer deposition (ALD). The presence of a remote radio frequency plasma source enables in situ experiments during both thermal as well as plasma-enhanced ALD. The system has been successfully installed at different beam line end stations at the European Synchrotron Radiation Facility and SOLEIL synchrotrons. Examples are discussed of in situ GISAXS and XRF measurements during thermal and plasma-enhanced ALD growth of ruthenium from RuO4 (ToRuS™, Air Liquide) and H2 or H2 plasma, providing insights in the nucleation behavior of these processes. [ABSTRACT FROM AUTHOR]

We study by grazing incidence x-ray diffraction the strain field induced by periodic double steps on a Si(1 1 15) surface that is a vicinal of a Si(001) surface misoriented by 5.4° towards the (110) direction. The best fit of the experimental structure factors is reached on the basis of the rebonded DB step edge model and the displacement field is well characterized assuming that steps are described by parallel rows of extended buried elastic dipoles. The dipole characteristics are the dipole position with respect to the step edge, thedipole amplitude (2.0 ± 0.5 nN), and the lever arm Ω = 5.3° and force F = 3.7° orientations. We show that the dipole is dominated by a large stretch component localized between the lower and the upper corners of the step, which we assign to the presence of the rebonded atom at the step. [ABSTRACT FROM AUTHOR]

We report on the magnetization at the Cr/MgO interface, which we studied through two complementary techniques: angle-resolved photoemission spectroscopy and polarized neutron reflectivity. We experimentally observe an enhanced interface magnetization at the interface, yet with values much smaller than the ones reported so far by theoretical and experimental studies on Cr(001) surfaces. Our findings cast some doubts on the interpretations on previous works and could be useful in antiferromagnetic spin torque studies. [ABSTRACT FROM AUTHOR]

MnSi has been extensively studied for five decades; nonetheless detailed information on the Fermi surface (FS) symmetry is still lacking. This missed information prevents a comprehensive understanding of the nature of the magnetic interaction in this material. Here, by performing angle-resolved photoemission spectroscopy on high-quality MnSi films epitaxially grown on Si(111), we unveil the FS symmetry and the evolution of the electronic structure across the paramagnetic-helimagnetic transition at Tc ~40K, along with the appearance of sharp quasiparticle emission below Tc. The shape of the resulting FS is found to fulfill robust nesting effects. These effects can be at the origin of strong magnetic fluctuations not accounted for by the state-of-the-art quasiparticle self-consistent GW approximation. From this perspective, the unforeseen quasiparticle damping detected in the paramagnetic phase and relaxing only below Tc, along with the persistence of the d-band splitting well above Tc, at odds with a simple Stoner model for itinerant magnetism, opens the search for exotic magnetic interactions favored by FS nesting and affecting the quasiparticle lifetime. [ABSTRACT FROM AUTHOR]

Scanning tunneling microscopy (STM) and grazing-incidence x-ray diffraction (GIXD) have been used tofollow in situ the growth and the structure of Au-Cu nanoparticles (NPs) formed on TiO2(1 10) by successive metal evaporations. STM observations of the same area of the substrate highlight the strong dependence between the sequence of deposition and the final result. Deposition of Cu first leads to a system where both Au-Cu and pure Au NPs coexist. Deposition of Au first ensures growing mostly bimetallic NPs. GIXD results show that Cu alloys instantaneously with Au NPs at room temperature. Similar observations during evaporation of Au on Cu NPs show that some of the Au atoms alloy with Cu whereas the rest remain at the NP shell. This is attributed both to kinetics and thermodynamics origins. [ABSTRACT FROM AUTHOR]

We compared the anti-estrogen receptors (ER) SP1, 6F11, and 1D5 antibodies in breast carcinoma cases with different ranges of positive cells to evaluate whether this could generate different therapies for patients. We selected 66 cases of breast cancer, each of which was immunostained with the 3 antibodies. 1D5 was less sensitive than SP1 and 6F11, as seen in 26, 20, and 21 negative cases, respectively. Nine cases showed differences in endocrine-therapy indications, of which 8 1D5-negative cases showed low positivity for SP1 and/ or 6F11. However, these cases were prevalently G3, progesterone receptor-negative or low-positive, with high Ki-67 and positive HER-2 findings, all biological features associated with endocrine resistance. Finally ER values obtained with these 3 antibodies had no implications for chemotherapy. [ABSTRACT FROM AUTHOR]

Abstract: Autonomous driving is one of the most interesting fields of research, with a number of important applications, like agricultural, military and, most significantly, safety. This paper addresses the problem of designing a general purpose path planner and its associated low level control for autonomous vehicles operating in unknown environments. Different kinds of inputs, like the results of obstacle detection, ditch localization, lane detection, and global path planning information are merged together using potential fields to build a representation of the environment in real-time; kinematically feasible trajectories, based on vehicle dynamics, are generated on a cost map. This approach demonstrated both flexibility and reliability for vehicle driving in very different environments, including extreme road conditions. This controller was extensively tested during VIAC, the VisLab Intercontinental Autonomous Challenge, a 13,000km long test for intelligent vehicle applications. The results, collected during the development stage and the experiment itself, are presented in the final part of this article. [Copyright &y& Elsevier]

Abstract: We have studied by Grazing Incidence X-ray Diffraction (GIXD) the strain field induced by periodic triple steps on a Si(7710) surface that is a vicinal of Si(111) surface 10° misoriented towards the direction. We find that the strain field induced by the triple steps is well described by an elastic model in which the steps are modelized by parallel rows of buried elastic dipoles. The best fit of the experimental results is reached on the basis of the (7710) surface structure model proposed by Teys et al. (Surface Science 600 (2006) 4878). The so-obtained dipole characteristics are the dipole amplitude (decomposed in a stretch component P T =1.5nN and a torque component P S =0.2nN) as well as the lever arm Ω=170° and force Φ=81° orientations of the dipole. We also determine the prefactor of the elastic interaction energy between triple steps A el. =0.52eVÅ we discuss in the light of other independent measurements. [Copyright &y& Elsevier]

Abstract: In view of understanding silicon incorporation in the δ doping process of GaAs (001), Si atoms have been deposited, under UHV, on a α(2×4) arsenic terminated substrate. In the low coverage regime, a transition to a less As rich (3×2) reconstructed Si–GaAs (001) surface was observed whose atomic structure has been investigated by grazing incidence X-ray diffraction performed in situ. Silicon is found to occupy not only a Ga substitutional site, precursor of a donor dopant but also to form nuclei for neutral clusters, on a template made by the (3×2) GaAs (001) reconstructed surface observed by Martrou et al. [Phys. Rev. B 72 (2005) 241307®]. The maximum surface concentration of donor-like silicon is estimated at 1.04×1014 cm−2 (1/6th monolayer). [Copyright &y& Elsevier]

Background: Monitoring adverse events during chemotherapy by clinicians is a standard practice but clinicians may report fewer side-effects or lower symptom severity than patients. Our aim was to compare symptoms self-reported by patients with symptoms registered by clinicians and nurses, to assess validity of a nurse reporting. [ABSTRACT FROM PUBLISHER]

Background: Myopericytoma is a rare tumor deriving from the perivascular myoid cellular environment, it’s usually described in soft tissues of the extremities and closed to vascular structures; intracranial localization is even more unusual with only nine cases reported in literature. We describe the first combined treatment of a myopericytoma involving the central nervous system with microsurgery and Gamma Knife radiosurgery. Case report: A 19 year-old female presented with worsening nuchal headache started one week before hospitalization. Computed tomography scan and subsequent magnetic resonance imaging showed a posterior cranial fossa well-circumscribed enhancing lesion attached to the right tentorial edge, radiologically suggestive for meningioma. She underwent gross total surgical excision through a retrosigmoid approach. Histopathology revealed a myopericytoma. At 3 months follow-up a tumor regrowth was found, with also supratentorial extension. In order to minimize the risks of a second surgical operation, Gamma Knife radiosurgery was performed obtaining a remarkable response, with no radiological evidence of residual tumor or recurrence 2 years after radiosurgery. The patient is neurologically asymptomatic. Conclusions: Myopericytoma is a novel class of perivascular tumors, it has mostly a benign course and based on the actual literature, a gross total resection should be the mainstay of treatment, when achievable. Nowadays, no preoperative study can allow to myopericytoma diagnosis that depends on histological examination, since it can mimic meningioma or cerebrovascular malformations on imaging. Surgical resection combined with Gamma Knife radiosurgery may be considered for high-risk surgical residual or recurrent intracranial myopericytomas. [ABSTRACT FROM AUTHOR]

We report on a step-induced morphological modification in Cobalt thin films (from 5 to 90 monolayers (ML)) on Au(1 1 1) substrates studied by grazing incidence X-ray diffraction (GIXD). When the cobalt film is deposited on the highly stepped Au(2 3 3) substrate its structure is found to be mainly face centered cubic (FCC) whereas its natural bulk structure is hexagonal close-packed (HCP). Relaxation and stacking fault probability have been determined using a simple diffraction model which fits all the GIXD data. A vicinal Co interface including this stacking fault probability and a small rotation of the Co(1 1 1) planes with respect to the Au(1 1 1) planes is proposed which is in exact registry with the Au vicinal surface. [Copyright &y& Elsevier]

We have studied by grazing incidence X-ray diffraction the self-ordering of the Cu–CuO stripe pattern. By comparing the experimental results to molecular dynamics simulations and anisotropic linear elastic calculations, we have been able to determine the atomic relaxations within the Cu substrate. The results show the importance of the crystalline anisotropy in the relaxation field. These relaxations are due to the surface stress difference Δσ between oxygen-covered and bare Cu(1 1 0) regions. For the different oxygen coverages studied, we have always found Δσ=1.0±0.1 N m−1. This surface stress difference is shown to be the origin of the self-ordering. [Copyright &y& Elsevier]

• Synchrotron-based in situ GISAXS and XRF are applied during Pd plasma-enhanced ALD. • The nucleation and the evolution in Pd nanoparticle morphology is investigated. • Pre-pulses with trimethylaluminum enhance the initial coverage of Pd nanoparticles. • The role of extra O 2 plasma pulse, with H 2 plasma as co-reactant, is investigated. • Precise control of the Pd nanoparticle dimensions and coverage is achieved. The morphology evolution of supported palladium nanoparticles (Pd NPs) during plasma-enhanced atomic layer deposition using palladium hexafluoroacetylacetonate (Pd(hfac) 2) as precursor was investigated using in situ and ex situ X-ray fluorescence (XRF) and grazing incidence small angle X-ray scattering (GISAXS), as well as ex situ scanning electron microscopy (SEM). The initial areal density of Pd NPs increases through adding cycles of the three-step process using Pd(hfac) 2 , H 2 plasma and trimethylaluminum (TMA) prior to the standard Pd(hfac) 2 + H 2 plasma process. The participation of an O 2 plasma exposure as additional co-reactant before or after the H 2 plasma step also plays a role in the nucleation density and particle coalescence, affecting also the shape of the deposited particles. Based on the gathered knowledge, a synthetic approach that enables precise control of the Pd nanoparticle dimensions and coverage is developed. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Structural properties of high density, nanometric size germanium dots grown on a silicon (001) surface covered by a very thin (1.2 nm thick) silicon oxide layer have been investigated by in-situ grazing incidence x-ray diffraction (GIXD) and ex-situ atomic force microscopy. Growth under molecular nitrogen partial pressure of 10-5 Torr yielded a high density (∼4×1010/cm2) of dots. The dot size can be progressively increased by successive depositions of germanium. GIXD investigations show that dots grow in epitaxial relationship to the silicon (001) substrate and that after few successive depositions, the dots are composed of pure and fully relaxed germanium. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Using highly controlled coverages of graphene on SiC(0001), we have studied the structure of the first graphene layer that grows on the SiC interface. This layer, known as the buffer layer, is semiconducting. Using x-ray reflectivity and x-ray standing wave analysis, we have performed a comparative study of the buffer layer structure with and without an additional monolayer graphene layer above it. We show that no more than 26% of the buffer carbon is covalently bonded to Si in the SiC interface. We also show that the top SiC bilayer is Si depleted and is likely the cause of the incommensuration previously observed in this system. When a monolayer graphene layer forms above the buffer, the buffer layer becomes less corrugated with signs of a change in the bonding geometry with the SiC interface. At the same time, the entire SiC interface becomes more disordered, presumably due to entropy associated with the higher growth temperature. [ABSTRACT FROM AUTHOR]

Using vicinal surfaces as a template for heteroepitaxial growth offers a unique possibility to control the orientation and the crystallinity of the grown layer. The study presented here focuses on the growth of Ag on a carefully chosen Ni(11 9 9) substrate. Ag adopts a Stranski-Krastanov growth mode with a slightly constrained wetting layer limited to two monolayers on which well crystallized islands grow. The specific orientation of the Ni substrate leads to Ag(7 9 9) orientation for the Ag thin film and it prevents the formation of twin and stacking fault. [ABSTRACT FROM AUTHOR]

Order-disorder transition of the epitaxial surface alloy of bulk immiscible elements Au1-x Fex on Ru(0001) is studied using complementary experiments of scanning tunneling microscopy and grazing incidence x-ray diffraction. For x ≃ 1/3, we evidence an apparent continuous transition towards disorder with increasing temperature from 550 to 700 K. An ordered Au2 Fe two-dimensional alloy is found to be composed of nanometer size domains of the three variants that switch to a two-dimensional solid solution with temperature. A two-levels model is developed to analyze those results which conducts to interpret this phase transition as the result of an order-disorder transition within two dimensional uncorrelated grains, or domains, with nearly fixed size. This system is a good candidate in order to study two-dimensional phase transitions of surface alloy, a largely unexplored domain but crucial to understanding thermal stability of bimetallic nanoparticles. [ABSTRACT FROM AUTHOR]