An instrumental variable method for robot identification based on time variable parameter estimation

This paper considers the data-based identification of industrial robots using an instrumental variable method that uses off-line estimation of the joint velocities and acceleration signals based only on the measurement of the joint positions. The usual approach to this problem relies on a ‘tailor-made’ prefiltering procedure for estimating the derivatives that depends on good prior knowledge of the system’s bandwidth. The paper describes an alternative Integrated Random Walk SMoothing (IRWSM) method that is more robust to deficiencies in such a priori knowledge and exploits an optimal recursive algorithm based on a simple integrated random walk model and a Kalman filter with associated fixed interval smoothing. The resultant IDIM-IV instrumental variable method, using this approach to signal generation, is evaluated by its application to an industrial robot arm and comparison with previously proposed methods

Iron: a target for the management of Kaposi's sarcoma?

BACKGROUND: Kaposi's sarcoma (KS) is a mesenchymal tumour associated with human herpesvirus-8 infection. However, the incidence of human herpesvirus-8 infection is far higher than the prevalence of KS, suggesting that viral infection per se is not sufficient for the development of malignancy and that one or more additional cofactors are required. DISCUSSION: Epidemiological data suggest that iron may be one of the cofactors involved in the pathogenesis of KS. Iron is a well-known carcinogen and may favour KS growth through several pathways. Based on the apoptotic and antiproliferative effect of iron chelation on KS cells, it is suggested that iron withdrawal strategies could be developed for the management of KS. Studies using potent iron chelators in suitable KS animal models are critical to evaluate whether iron deprivation may be a useful anti-KS strategy. SUMMARY: It is suggested that iron may be one of non-viral co-factors involved of KS pathogenesis and that iron withdrawal strategies might interfere with tumour growth in patients with KS

Cytocompatibility of Medical Biomaterials Containing Nickel by Osteoblasts: a Systematic Literature Review

The present review is based on a survey of 21 studies on the cytocompatibility of medical biomaterials containing nickel, as assessed by cell culture of human and animal osteoblasts or osteoblast-like cells. Among the biomaterials evaluated were stainless steel, NiTi alloys, pure Ni, Ti, and other pure metals. The materials were either commercially available, prepared by the authors, or implanted by various techniques to generate a protective layer of oxides, nitrides, acetylides. The observation that the layers significantly reduced the initial release of metal ions and increased cytocompatibility was confirmed in cell culture experiments. Physical and chemical characterization of the materials was performed. This included, e.g., surface characterization (roughness, wettability, corrosion behavior, quantity of released ions, microhardness, and characterization of passivation layer). Cytocompatibility tests of the materials were conducted in the cultures of human or animal osteoblasts and osteoblast-like cells. The following assays were carried out: cell proliferation and viability test, adhesion test, morphology (by fluorescent microscopy or SEM). Also phenotypic and genotypic markers were investigated. In the majority of works, it was found that the most cytocompatible materials were stainless steel and NiTi alloy. Pure Ni was rendered and less cytocompatible. All the papers confirmed that the consequence of the formation of protective layers was in significant increase of cytocompatibility of the materials. This indicates the possible further modifications of the manufacturing process (formation of the passivation layer)

Preliminary investigations of storage battery locomotives : specifications laboratory tests permissible schedule /

"Publications on investigations of electrical equipment": p. 34-35.Running title: Storage-battery locomotives.First edition, October, 1920. cf. verso of t.-p.At head of title: Department of the interior. John Barton Payne, secretary. Bureau of mines. Frederick G. Cottrell, director.Includes Bibliographic references. Bibliography: p.Mode of access: Internet

United States Bureau of Mines Bulletin 313

From Introduction: "The purpose of this paper is therefore to give essential data in regard to the construction of approved storage-battery locomotives and power trucks.

United States Bureau of Mines Bulletin 343

From Description of Permissible Loaders and Conveyors: "The following descriptions of permissible loading machines and conveyors now included in the bureau's list of approved equipment are given to indicate to mine operators not only the types available but also show to some extent the special features employed in designing machines that minimize the hazard of gas and dust ignitions. Furthermore, the authors hope that the descriptions will have some value to manufactures who may contemplate entering this field of special design.

United States Bureau of Mines Bulletin 382

From Schedules, Approvals, and Approval Plates: " This schedule has been revised from time to time to conform with information gained from testing a large variety of equipment and to bring the requirements in line with new developments in the art. As the approval plate on a machine evidences compliance with the safety requirements established by the Bureau the user, in fairness to the Bureau and the manufacturer, should not operate such a machine if it has been changed from the design approved without authority or if it has become unsafe through neglect or accident. The machine should be in proper condition, or the approval plate should be removed and destroyed.

La clarté du concept de soi et le coping proactif : des ressources personnelles pour faire face aux stresseurs scolaires?

International audienceLa présente étude concerne le versant psychologique de la qualité de vie scolaire. Elle s'intéresse à deux déterminants potentiels du bien-être subjectif de collégiens en classe de 3ème : la clarté du concept de soi qui renvoie à la certitude, la cohérence et la stabilité de la description de soi (Campbell et al., 1996) et le coping proactif, forme de coping orienté vers la gestion des situations futures (Schwarzer, 2000). L'hypothèse testée est celle d'un modèle de médiation dans lequel la clarté du concept de soi exerce un effet positif sur le coping proactif qui à son tour réduit la pression et les difficultés scolaires perçues (stresseurs), lesquelles influencent négativement le bien-être de l'élève. Dans ce but, 410 élèves de 3ème ont complété une échelle de clarté du concept de soi (Brunot, Valéau & Juhel, 2015), une échelle de coping proactif pour adolescents (Greenglass, Schwarzer et Laghi, 2008) et 7 items mesurant la pression et les difficultés scolaires perçues. Enfin, une mesure de la composante affective du bien-être subjectif a été effectuée à l'aide de la SPANE (Diener et al., 2010). Les résultats de la modélisation en équations structurelles confortent le modèle envisagé. La discussion, tout en soulignant les limites de cette étude au caractère transversal, suggèrera l'intérêt de tester auprès d'élèves des programmes visant le développement de la connaissance de soi et des stratégies de coping proactif pour réduire leur vulnérabilité face aux stresseurs scolaires et améliorer ainsi leur bien-être et, plus généralement, la qualité de vie scolaire perçue

Response of fibroblast activity and polyelectrolyte multilayer films coating titanium

International audienceOBJECTIVES:The study of surface properties is a recent and crucial issue in the biomaterial fields applied to Odontology. The reference biomaterial in dental implantology is titanium. The principal objective is a perfect bio-integration in the oral ecosystem, both in terms of mucosal and bone tissues. The aim of this work was to optimize the tissue-titanium interface by applying polyelectrolyte multilayer films on the surface of titanium.METHODS:The experimental study was undertaken on pure titanium samples. Two types of film ending with polycations or polyanions were selected. Both film types were built with a first poly(ethyleneimine) (PEI) base layer and composed either of poly(styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) or of hyaluronic acid (HA) and poly(l-lysine) (PLL) layers. Final architectures were as follows: PEI-(PSS/PAH)(10), or PEI-(PSS/PAH)(10)-PSS, or chemically cross-linked PEI-(HA/PLL)(10) or PEI-(HA/PLL)(10)-HA. An analysis of the physicochemical characteristics of the surfaces was carried out by tensiometry measurements (dynamic contact angle, wettability, contact angle hysteresis) and atomic force microscopy. A biological study with human fibroblasts was followed over a 7-day culture period at days 0, 2, 4 and 7 to observe the cellular response in terms of morphology (scanning electron microscopy) and viability (Mosmann's test).RESULTS:The results showed that polyelectrolyte multilayer films could be successfully deposited onto titanium as previously described for glass or composite. Fibroblast adhesion and proliferation was strongly dependent on film type. SEM observations of cells on the different films agreed with the viability cell test. Furthermore, films containing PSS/PAH generated a better cellular response than films containing cross-linked HA/PLL.CONCLUSION:PSS/PAH polyelectrolyte films coating titanium could represent a new approach for oral bio-integration with great potential for clinical application in the fields of dental implantology. More particularly, the specific biofunctionalization of PSS/PAH films coating titanium could be envisioned by introducing layers of molecules that encourage the bio-integration process between the films