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Peri-implant debris certainly lead to osteolysis, necrosis, pseudotumor formation, tissue granulation, fibrous capsule contractions, and even implant failure. For the three-dimensional (3D) printed cage, impaction during cage insertion is one of the most potential sources of fracture debris. A finite-element study was carried out to reduce the impact-induced debris of the 3D-printed cage. This study focused on the design strategy of solid and cellular structures along the load-transferring path. Using the finite-element method, the cellular structure of the transforaminal lumbar interbody fusion (TLIF) cage was systematically modified in the following four variations: a noncellular cage (NC), a fully cellular (FC) cage, a solid cage with a cellular structure in the middle concave (MC) zone, and a strengthened cage (SC) in the MC zone. Three comparison indices were considered: the stresses at the cage-instrument interfaces, in the MC zone, and along the specific load-transferring path. The NC and FC were the least and most highly stressed variations at the cage-instrument interfaces and in the MC zone, respectively. Along the entirely load-transferring path, the FC was still the most highly stressed variation. It showed a higher risk of stress fracture for the FC cage. For the MC and SC, the MC zone was consistently more stressed than the directly impacted zone. The further strengthened design of the SC had a lower peak stress (approximately 29.2%) in the MC zone compared with the MC. Prior to 3D printing, the load-transferring path from the cage-instrument interfaces to the cage-tissue interfaces should be determined. The cage-instrument interfaces should be printed as a solid structure to avoid impact-induced fracture. The other stress-concentrated zones should be cautiously designed to optimize the coexistence strategy of the solid and cellular structures.

In a series of papers in the 1980s Alexander Holevo proved a classification theorem for continuous quantum measurement processes, or, as they would today be called, stationary quantum trajectories in continuous time. His main tools were functional analytic in character: starting from a Bochner-type inequality he employed dilation techniques for positive definite kernels. Here, we give an alternative, more probabilistic proof: we use weak convergence of measures and employ Lévy’s Continuity Theorem. We clarify the boundedness conditions in Holevo’s theorem, and supply a simple example from quantum optics.

Previous research applied sliding mode control with a sliding perturbation observer (SMCSPO) algorithm as a robust controller to control a surgical robotic instrument and reported that reaction force loaded on the tip can be estimated similarly by the sliding perturbation observer (SPO). However, some factors, such as friction, in which it is difficult to find the model parameters beforehand, can have an effect on the reaction force estimation because the factors are included in the estimated perturbation. This paper addresses the SPO based reaction force estimation method to extract a pure reaction force on a surgical robot instrument in the case of including Coulomb friction due to the operation of cable-pulley structure. Coulomb friction can be estimated experimentally and compensated for from the estimated perturbation. An experimental evaluation was performed to prove the suggested estimation method. The results show that SPO can be substituted for sensors to measure the reaction force. This estimated reaction force will be used to realize the haptic function by sending the reaction force to a master device for a surgeon. The results will help to create surgical benefit such as shortening the practice time of a surgeon and providing haptic information to the surgeon by using it as haptic signal to protect an organ by forming a force boundary.

A general form of the Wigner-Araki-Yanase theorem is proved in the framework of quantum measurement theory based on the notion of instrument.

Systemic lupus erythematosus (SLE) is a complicated multisystem autoimmune disease that carries substantial mortality and morbidity. The development of new therapies is partly hindered by the lack of a flawless instrument to gauge disease activity in different organs for the primary efficacy outcome. Until a global consensus is reached regarding the most preferred assessment tool, application of any of the existing disease activity indices is acceptable in clinical practice and research. However, one should have a more thorough understanding of the strength and limitations of individual disease activity instruments. This article updates the SLE disease activity indices commonly used in clinical trials and their latest stage of development.

Many economic theories and hypotheses have implications on and only on a moment condition or a set of moment conditions. A popular method to estimate model parameters contained in the moment condition is the Generalized Method of Moments (GMM). In this chapter, we first provide some economic examples for the moment condition, and define the GMM estimator. We then establish the consistency and asymptotic normality of the GMM estimator. Since the asymptotic variance-covariance matrix of a GMM estimator depends on the choice of a weighting matrix, we introduce an asymptotically optimal two-stage GMM estimator with a suitable choice of a weighting matrix. With the construction of a consistent asymptotic variance estimator, we then propose an asymptotically χ² Wald test statistic for the hypothesis of interest, and a model specification test for the moment condition.

The ASTRO-H satellite is an X-ray astronomy satellite currently planned to be launched in 2015. It is a successor of the series of Japan's X-ray astronomy satellites, and is being developed under an international collaboration with the US, some European countries, and Canada. The satellite carries four scientific payloads: SXS (soft X-ray spectrometer), SXI (soft X-ray imager), HXI (hard X-ray imager), and SGD (soft gamma-ray detector), providing a non-dispersive high-resolution spectroscopic capability with SXS and a wide energy coverage with the four instruments. We present the status of the development and some of the scientific prospects related to the interest of the session, which includes high-resolution X-ray spectroscopy of neutron stars.

The paper reviews the results of St. Petersburg metrologists work on the development of dynamic measurement and instrument models, as well as algorithms for measurement data processing. The results were obtained in the 60-ies – 80-ies of the past century within the framework of three generalized formal problems, two of which are related to ill-posed inverse problems. The developed methods for dynamic measurement instrument identification are presented. The general characteristic is given for the problem of an input signal recovery of the dynamic measurement instrument. The topicality of the obtained results is pointed out.