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We use narrow spectral lines from the X-ray spectra of various highly charged ions to measure low-energy tail-like deviations from a Gaussian response function in a microcalorimeter X-ray spectrometer with Au absorbers at energies from 650 to 3320 eV. We review the literature on low-energy tails in other microcalorimeter X-ray spectrometers and present a model that explains all the reviewed tail fraction measurements. In this model, a low-energy tail arises from the combination of electron escape and energy trapping associated with Bi X-ray absorbers. [ABSTRACT FROM AUTHOR]

Nitric oxide adsorption, decomposition, and desorption were studied on Rh(100) in the temperature range from 88 to 1100 K using electron energy loss spectroscopy (EELS) and temperature programmed desorption (TPD). The EEL spectrometer was equipped with a multichannel detector for fast data acquisition. There are two adsorption states of NO on Rh(100), designated α1NO and α2NO, characterized by vibrational modes at 114 and 196 meV, respectively, and assigned to a lying down or highly inclined species and a vertically adsorbed species. The populations of the two states as functions of the total NO coverage were measured on the clean surface and with coadsorbed oxygen and CO. These coadsorbed species, whether adsorbed before or after the NO, increase the α2 population at the expense of α1. A model that includes an adsorbate–adsorbate interaction (rangeapprox. 7 Å) which converts α1NO to α2NO and which permits adsorbing NO to diffuse so as to favor α1 adsorption fits the measured populations of the two species on the clean surface and produces a saturation coverage of 0.62 ML (1 ML=1.39×1015 molecule/cm2), in good agreement with the published result. Decomposition and desorption of NO at temperatures >90 K were studied by a series of temperature programmed EELS (TP-EELS) experiments at heating rates from 0.048 to 5.25 K/s and by TPD. At saturation, 62% of the NO decomposes as evidenced by the extent of N2 desorption in TPD peaks at 460 and 770 K. The remaining NO desorbs molecularly near 430 K with an activation energy Ea=28±3 kcal/mol and first order preexponential v=1014±1 s-1, as determined by TP-EELS. The decomposition of α1NO occurs near 170 K with Ea=10.5±0.7 kcal/mol and v=1011.8±0.7 s-1. The extent of the α2NO decomposition and its activation energy are strongly coverage dependent. The temperature at which its decomposition rate is a maximum approaches that of α1NO at low... [ABSTRACT FROM AUTHOR]

The CO adsorption site occupations on Fe(111) have been determined as a function of coverage and temperature using temperature programmed desorption (TPD) and time-resolved electron energy loss spectroscopy (TREELS). CO does not adsorb in a thermally equilibrated distribution among the four adsorption sites at 100 K; selective adsorption occurs due to different coverage and temperature dependent sticking probabilities. Upon heating, the nonequilibrium distribution relaxes via CO site changes. At approx. 250 K and moderate coverage, CO adsorbed in the on-top site changes to the bridge-like shallow hollow site. A heating rate variation analysis yielded an activation barrier E=4.5±0.5 kcal mol-1 and effective first order preexponential ν1=101.5±0.5 s-1 for this process. A similar site change from the deep hollow to the shallow hollow occurs at low coverage near 160 K. Dissociation occurs at approx. 300 K when all CO are adsorbed in the shallow hollow site. With low coverages the dissociation reaction occurs with E=20±5 kcal mol-1 and ν1=1011±2 s-1. The resulting adsorbed atomic C and O recombinatively desorb at approx. 760 K with Eapprox. 48 kcal mol-1 and ν2approx. 0.1 cm2 s-1. At higher coverages, in addition to dissociation, some of the CO in the shallow hollow desorb, with Eapprox. 32 kcal mol-1 and ν1approx. 1017 s-1. [ABSTRACT FROM AUTHOR]

The intensities of the stretch modes of CO adsorbed in bridge and top sites on Rh(100) are presented as a function of coverage, temperature, and during reaction with O. Following adsorption at 90 K, the top site is predominantly occupied at low coverages, and at 0.5 atomic monolayers (ML) only the top site is occupied and a c(2×2) low energy electron diffraction (LEED) pattern is observed. With higher coverages the bridge site is increasingly occupied, and at saturation a p(4(2)1/2×(2)1/2)R45° LEED pattern is observed. The occupations of bridge and top sites at a fixed (0.5 ML) total coverage are observed to vary reversibly when the temperature is linearly ramped from 87 to 371 K and back down to 90 K; the difference in the binding enthalpy of bridge and top sites is determined to be 1.10±0.06 kcal mol-1. The enthalpy difference between bridge and top sites is also obtained from temperature programmed EELS (TP-EELS) which follows the site occupations as the temperature is increased past desorption. Surface order is found to have a significant effect on the normalized intensities of CO in conventional EEL spectra. The normalized intensities in angle integrated spectra, obtained by modulating the voltage difference applied to the two halves of the split analyzer input lenses, are insensitive to changes in the degree of surface order. The effect of low frequency frustrated rocking motions of diatomic molecules on the temperature dependence of the intensities observed in electron energy loss spectroscopy (EELS) is discussed. TP-EELS of coadsorbed CO and O allows the direct observation of the changes in the occupation of CO binding sites during reaction, and the results are correlated with LEED and temperature programmed reaction spectroscopy (TPRS) measurements of the reaction. Segregation of the reactants during the reaction is important. [ABSTRACT FROM AUTHOR]

The magnitudes of the challenges facing electron-based metrology for post-CMOS technology are reviewed. Directed self-assembly, nanophotonics/plasmonics, and resistive switches and selectors are examined as exemplars of important post-CMOS technologies. Materials, devices, and architectures emerging from these technologies pose new metrology requirements: defect detection, possibly subsurface, in soft materials, accurate measurement of size, shape, and roughness of structures for nanophotonic devices, contamination-free measurement of surface-sensitive structures, and identification of subtle structural, chemical, or electronic changes of state associated with switching in non-volatile memory elements. Electron-beam techniques are examined in the light of these emerging requirements. The strong electron-matter interaction provides measurable signals from small sample features, rendering electron-beam methods more suitable than most for nanometer-scale metrology, but as is to be expected, solutions to many of the measurement challenges are yet to be demonstrated. The seeds of possible solutions are identified when they are available. [ABSTRACT FROM AUTHOR]

Background: Gaucher disease (GD) is an autosomal recessive disorder produced by mutations in the glucocerebrosidase gene (GBA), causing storage of glucosylceramide in reticuloendothelial cells in multiple organs. Traditionally, the prediction of the phenotype based on the genotype has been reported to be limited. Subjects and Methods: We investigated the correlation between the enzymatic residual activity (ERA) and the phenotype at diagnosis of the disease in 45 GD Spanish patients (44 with type I and 1 with type III GD). The genotype involved two of the following previously expressed proteins: c.517A>C (T134P), 1%; c.721G>A (G202R), 17%; c.1090G>T (G325W), 13.9%; c.1208G>A (S364N), 4.1%; c.1226A>G (N370S), 17.8%; c.1246G>A (G377S), 17.6%; c.1289C>T (P391L), 8.5%; c.1448T>C (L444P), 3%; and c.1504C>T (R463C), 24.5%. Recombinant alleles, deletion of 55 bp in exon 9 and 84GG mutation were considered as mutations with no residual enzymatic activity. Results: The ERA showed a statistically significant correlation with chitotriosidase (P<0.001), age (P<0.001), spleen size (P<0.001), 'Zimran's Severity Score Index' (P<0.01) and the 'Gaucher Disease Severity Score Index--Type I' (P< 0.0001) at diagnosis of the disorder. Previous to any medical intervention, a comparison between the ERA and bone involvement, demonstrated a statistically significant relationship (P<0.01) between the two variables. Conclusions: This study data allowed us to define a new criterion for prognostic assessment of the disease at diagnosis, called Protein Severity Index, which expresses the theoretical severity of the genotype presented by patients, according to the corresponding ERA. [ABSTRACT FROM AUTHOR]

Histiocytic sarcoma (HS) is a neoplasm derived from histiocytes. Its diagnosis was not clear until its immunohistochemistry profile was correctly established. Not much is known about its genetic properties. We report a case of a 48-year-old male patient whose bone marrow was almost completely occupied by monomorphic medium size neoplastic cellularity. Its immunohistochemical profile was CD68+, CD4+ CD45+ with negativity of other dendritic cells, and other lineage markers. Cytogenetic study showed 4 related clones: one with trisomy 8 and extra material on the short arms of chromosome 4; a second line with tetrasomy of chromosome 8, add(4)(p16); the third clone had the same alterations as the previous and deletion of chromosome 3 at q11; the fourth line had tetrasomy 8 and translocation t(3;5)(q25;q35). To our knowledge this is the first HS case showing chromosome 8 trisomy and tetrasomy and the other described alterations. [ABSTRACT FROM AUTHOR]

The design, construction, and operation of a high-resolution electron energy-loss spectrometer incorporating a multidetector of 96 discrete anodes are described. In conjunction with temperature and pressure perturbations, this fast data-acquisition spectrometer allows studies of surface kinetics and reaction mechanisms by accumulating spectra in as fast as 2 ms. A comprehensive hardware and software system has been developed that permits experimental control and data acquisition with an LSI 11/23 microcomputer. A routine increase in data-acquisition speed of ≊10, when compared to a conventional electron energy-loss apparatus, has been achieved when the spectrometer is operated with 10–20-meV resolution. [ABSTRACT FROM AUTHOR]

Abstract: When measuring rectangular and trapezoidal profile roughness specimens, the stylus tip increases the measured profile peak width and decreases the measured valley width. This can cause either an increase or a decrease in the apparent roughness average Ra, depending on the tip size and the ratio of peak width to valley width. Sometimes the change is larger than the combined measurement uncertainty from other sources. This raises the question as to whether measured surface parameters should be corrected for the effect of tip size. [Copyright &y& Elsevier]

Background: Knee osteoarthritis mainly affecting the lateral facet of the patella, especially in young patients, is a definite challenge to the surgeon. Our purpose was to investigate the long-term outcome of a simple operation such as the partial lateral facetectomy on middle-aged to elderly patients with predominant lateral patellofemoral osteoarthritis. Methods: A retrospective, long-term study of 39 knees (28 females, mean aged at surgery 61yearsold) with a minimum follow-up of 10years was performed. Evaluations included preoperative and postoperative questionnaires, physical examinations, and radiographs. Results: The main outcomes included the initial anterior pain relief, with higher scores using the Knee Society Score (that improved in 84% of the knees), and the eventual failure of the technique, including percentage of patients that required secondary total knee replacement (30% of the knees). Conclusion: Partial lateral facetectomy aiming to decrease the high pressure in the lateral facet of the patella confirmed frequent pain relief. This surgical procedure being minimally invasive, relatively simple, and effective in selected patients, is a valid early alternative to more complex operations and does not preclude further reconstructive surgery in case of disease progression. [ABSTRACT FROM AUTHOR]

Glioblastoma (GB) is the most common malignant CNS tumor. Incidence ingreases with age, peaking between 69 and 84 yers, and half of patients diagnosed have > 65 years. The question about how to treat these patients remains object of controversy. The purpose of this survey was to know the treatment recommendations for BG in academic Spanish hospitals. In 2018, surveys were e-mailed to all members of GEINO (Spanish Group for Neurooncology Reseach). The survey contained specific questions on the routine clinical practice regarding treatment recommendations for elderly patients with GB and anaplastic astrocytoma in different clinical situations: depending on ECOG, morbility, MGMT promoter methylation, age intervals (between 65-70 y, 70-80 y, >80 y). Response options were: a) Stupp regimen, b) Perry regimen, c) Radiation or TMZ depending on MGMT status and d) supportive care. Participants were also asked if they used MGMT status to select patients for Stupp or Perry regimen. Twenty-six neuro-oncoligist from twenty-six hospitals completed the survey. Mean of hospital beds of the institutions were 833.19 (range 150-1500). Mean of hospital veds of the instituions were 833,19 (range 150-1500). Median number of new cases treated per year were 31 (range 8-80). In patients with ECOG 0-1 and between 65 and 70 years old, 80.8 % of participants would recommend treatment with Stupp regiment. For patients with ECOG 0-1 and between 70-80; 46.2 % recommenden Perry regimen in methylated (M) and unmethylated (UM) patients; 38.5 % recommended Stupp regimen in both. For with ECOG 0-1 and > 80 % yo, 46,2 % recommend Perry regimen in both M and UM; 3.8 % Stupp regimen; 15,4 % radiation or TMZ according to MGMT status. In patients with anaplastic astrocytoma aged 70-80 y, 46,2 % would recommend Perry regimen and 42,3 % Stupp regimen. Table: 411P Table: 411P Most recommend treatment Percentage of responders Glioblastoma, age 70-80 (PS 0-1, minor comorbility) Perry Stupp 46.2 % 38.5 % Glioblastoma, age >80 (PS 0-1, mior comorbility Perry 46.2 % Glioblastoma, age 65-70 (PS 0-1, minor comorbility) Stupp 80.8 % Glioblastoma, no MGMT methylation 70-80 >80 65-70 Stupp Perry Stupp 50 % 34.6 % 68.5 % Glioblastoma >65, PS > 2 Stupp 36.8 % Anaplastic astrocytoma 70-80 yo Perry 30.8 % Anaplastic astrocytoma >80 Perry 34.6 % Anaplastic astrocytoma 65-70 Stupp 53.8 % Our research demonstrates there is no uniform approach to the management of elderly patient with glioblastoma among academic neuro-oncologist. GEINO (Grupo Español de Investigación en Neurooncología). Has not received any funding. M. Vaz Salgado: Advisory / Consultancy, Travel / Accommodation / Expenses: Pharmamar; Advisory / Consultancy: Lilly, Eisai y Celgene; Research grant / Funding (self): Pfizer. M. Vieito Villar: Travel / Accommodation / Expenses: Roche. R. Luque: Honoraria (self), Travel / Accommodation / Expenses: Janssen-Cilag; Honoraria (self), Travel / Accommodation / Expenses: Sanofi Aventis; Honoraria (self), Travel / Accommodation / Expenses: Astellas Medivation; Honoraria (self), Travel / Accommodation / Expenses: Roche; Honoraria (self), Travel / Accommodation / Expenses: Novartis; Honoraria (self), Travel / Accommodation / Expenses: Pfizer; Honoraria (self), Travel / Accommodation / Expenses: Bristol Mayers Squibb; Honoraria (self), Travel / Accommodation / Expenses: EUSA Pharma. All other authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]