Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range

A modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays [Proc. SPIE 7077-7 (2007), Opt. Eng. 47, 073602 (2008)] has been proven to be an effective MTF calibration method for a number of interferometric microscopes and a scatterometer [Nucl. Instr. and Meth. A616, 172 (2010)]. Here we report on a further expansion of the application range of the method. We describe the MTF calibration of a 6 inch phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of millimeters

Revisiting the Effects of Gender Diversity in Small Groups on Divergent Thinking: A Large-Scale Study Using Synchronous Electronic Brainstorming

Numerous studies have examined the effects of gender diversity in groups on creative performance, and no clear effect has been identified. Findings depend on situational cues making gender diversity more or less salient in groups. A large-scale study on two cohorts (N = 2,261) was conducted among business students to examine the impact of the gender diversity in small groups on divergent thinking in an idea-generation task performed by synchronous electronic brainstorming. Participants were automatically randomized in three- or four-member groups to generate ideas during 10 min on a gendered or neutral task. Then, five categories of groups where the proportion of men/women in groups varied from three/four men to three/four women were compared to examine creative performance on three divergent thinking measures (fluency, flexibility, and originality). A Multivariate Generalized Linear Mixed Model (mGLMM) showed greater fluency in all-women groups than in other groups (except mixed-gender groups composed of two men and two women), and more specifically “solo” groups composed of a single woman/man among a majority of men/women. For flexibility and originality, the superiority of all-women groups was found only in comparison to “solo” groups composed of a single woman. As gender differences are more salient in “solo” groups than in other groups faultlines may appear in groups, leading to a deleterious impact on creative performance

Dax : Histoire et archéologie de la cité des eaux

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Troissereux, Oise (Picardie), “25-27 rue de Calais - tranche 3”. Une occupation mérovingienne et carolingienne : rapport de fouilles

L’opération a permis de détecter quatre phases d’occupation qui s’étendent de la Protohistoire ancienne à l’époque médiévale.Il s’agit tout d’abord d’un modeste ensemble de fosses isolées et réparties en deux points du site datées de l’âge du Bronze.Ensuite, se dessine un large fossé linéaire qui traverse le site d’est en ouest et se poursuit en dehors de l’emprise. Il n’a livré aucun reste mobilier mais les recoupements stratigraphiques montrent son antériorité par rapport à la première phase du haut Moyen Âge. Le comblement indique une utilisation vouée au drainage ou à l’apport d’eau d’un point situé dans le fond du vallon sec jusqu’au Thérain. Il est relié à une autre portion de fossé orientée nord-sud d’époque indéterminée mais probablement contemporaine de par leur relation.Enfin, l’ensemble de la parcelle est densément investie entre la seconde moitié du VIIe et le IXe siècle. L’occupation est matérialisée par de nombreux types de structures : des fours, des fonds de cabane, des trous de poteau, des silos, des puits, une sépulture et diverses fosses aux fonctions variées. Trois principaux secteurs de concentration de structures se dessinent : un secteur médian sud où se concentrent de nombreux bâtiments sur poteaux et de grandes fosses, un secteur oriental surtout marqué par la présence de fours domestiques et une dernière zone située à proximité de l’angle nord-est constituée de fosses et de trous de poteaux. L’ensemble est accompagné de structures réparties de manière plus lâche en périphérie de ces différents espaces.L’habitat principal situé dans la zone médiane s’accompagne de deux autres unités d’occupation. L’une d’entre elle a pu abriter une habitation de deuxième rang ou un groupement d’annexes, dans tous les cas la carte de répartition du mobilier atteste de sa position secondaire.Le type de structures rencontrées et l’organisation du site atteste d’une occupation vouée aux activités agro-pastorales. Comme d’autres établissements de la même période, cette unité agricole regroupe également un secteur d’activité plus spécifique et artisanal avec le secteur des fours culinaires.Même si cette unité a bien pu être mise en évidence, l’ensemble de l’occupation de cette période n’a sans doute pas été entièrement découverte. Il est fort probable que d’autres groupements se répartissent ailleurs dans cette vallée. D’ailleurs, plusieurs indices en témoignent au regard des résultats des diagnostics de 2011 et 2013. Il en est de même au sud comme le souligne la présence de mobilier dans les niveaux tourbeux. La présence de l’eau étant l’un des éléments primordiaux dans le choix d’implantation du site, il est fort probable que les berges du cours d’eau aient été également investies.Le site de Troissereux fait probablement partie intégrante d’un groupe de plusieurs unités réparties de manière plus lâche. Il est abandonné au cours de la période carolingienne. L’exemple de Troissereux permet d’apporter sa contribution aux débats sur la formation des villages au cour du haut Moyen Âge

Probing nanoscale structural and order/disorder phase transitions of supported Co-Pt clusters under annealing

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The prognostic value of erythrocyte polyamine in the post-nephrectomy stratification of renal cell carcinoma specific mortality.

International audiencePURPOSE: The polyamines spermine and spermidine are ubiquitous polycationic structures which are essential for cell proliferation and differentiation. Circulating polyamines, spermine and spermidine, represent valuable prognostic markers in prostate cancer, acute leukemia and supratentorial malignant glioma. We tested whether spermine and spermidine could improve the prognostic ability of several established predictors of cancer specific mortality after partial or radical nephrectomy for renal cell carcinoma. MATERIALS AND METHODS: Testing was performed on 399 patients with stages T(1-4), N(0-2), M(0-1) renal cell carcinoma who were treated with radical or partial nephrectomy at a single institution between 1990 and 2007. Univariable and multivariable Cox regression models tested the prognostic ability of spermine and spermidine levels in cancer specific mortality predictions. Covariates consisted of TNM stage, Fuhrman grade, tumor size and symptom classification. Harrell's concordance index (c-index) quantified accuracy and 200 bootstrap resamples were used to correct for overfit bias. RESULTS: The 5-year cancer specific mortality-free survival of patients with spermine levels 3 or less, 3.1 to 8, 8.1 to 13 and greater than 13 nmol/8x10(9) erythrocytes was 88.8%, 75.8%, 40.2% and 21.8%, respectively. Similarly the 5-year cancer specific mortality-free survival of patients with spermidine levels 12 or less, 12.1 to 15, 15.1 to 21 and greater than 21 nmol/8x10(9) erythrocytes was 79.0%, 56.6%, 53.2% and 27.4%, respectively. On multivariable analyses addressing cancer specific mortality after surgery spermine (p = 0.007) and spermidine (p = 0.04) achieved independent predictor status. Consideration of spermine and spermidine also improved the accuracy of established cancer specific mortality predictors by 2.2% (p <0.001). CONCLUSIONS: Spermine and spermidine may significantly improve the prognostic value of established cancer specific mortality predictors after partial or radical nephrectomy for all stages of renal cell carcinoma. Independent external validation of our findings is required

Characterization of electron microscopes with binary pseudo-random multilayer test samples

Verification of the reliability of metrology data from high quality x-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested [Proc. SPIE 7077-7 (2007), Opt. Eng. 47(7), 073602-1-5 (2008)} and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [Nucl. Instr. and Meth. A 616, 172-82 (2010)]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi2/Si multilayer coating with pseudo randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize x-ray microscopes. Corresponding work with x-ray microscopes is in progress