优秀人才缺乏导致大起大落欧洲教训为移动运营商敲响警钟

移动运营商在过去的12年中经历了一个爆发性增长的“火山期”和一个低增长的-一冰河期”。起落之间反映的是运营商在人才上的缺失,这一来自欧洲电信市场上的教训值得全球所有运营商警惕。     

On‐Demand Wrinkling Patterns in Thin Metal Films Generated from Self‐Assembling Liquid Crystals

In this work, a new, universal method is described that uses the photopatterning of liquid crystals, which is accurately translated into a controlled, intricately wrinkled metal surface. Remarkably, the patterns have an oscillation in amplitude of the wrinkles. This rapid method allows generation of intricate multidomain patterns and continuous circular structures, including azimuthal, radial, and even higher complexity arrangements as examples. These wrinkled gold surfaces are also strikingly visual, which is interesting for applications ranging from diffractive elements to fine jewelry.     

Cell‐Tethered Ligands Modulate Bone Remodeling by Osteoblasts and Osteoclasts

The goals of the present study are to establish an in vitro co‐culture model of osteoblast and osteoclast function and to quantify the resulting bone remodeling. The bone is tissue engineered using well‐defined silk protein biomaterials in 2D and 3D formats in combination with human cells. Parathyroid hormone (PTH) and glucose‐dependent insulinotropic peptide (GIP) are selected because of their roles in bone remodeling for expression in tethered format on human mesenchymal stem cells (hMSCs). The cell‐modified biomaterial surfaces are reconstructed from scanning electron microscopy images into 3D models for quantitative measurement of surface characteristics. Increased calcium deposition and surface roughness are found in 3D surface models of silk protein films remodeled by co‐cultures containing tethered PTH, and decreased surface roughness is found for the films remodeled by tethered GIP co‐cultures. Increased surface roughness is not found in monocultures of hMSCs expressing tethered PTH, suggesting that osteoclast‐osteoblast interactions in the presence of PTH signaling are responsible for the increased mineralization. These data point towards the design of in vitro bone models in which osteoblast‐osteoclast interactions are mimicked for a better understanding of bone remodeling.     

A physical optics approach to near field RCS computations

The scattered field of a perfectly conducting body treated using a physical optics approach is obtained in near field in either the monostatic or bistatic case. This approach opens new prospects for a broad range of applications in the areas of radar cross section (rcs) and antennas. Numerical examples for simple shapes (circular and rectangular plates) are given. Remarkable phenomena are found and discussed.     

Exploring time series retrieved from cardiac implantable devices for optimizing patient follow-up

Current cardiac implantable devices (IDs) are equipped with a set of sensors that can provide useful information to improve patient follow-up and prevent health deterioration in the postoperative period. In this paper, data obtained from an ID with two such sensors (a transthoracic impedance sensor and an accelerometer) are analyzed in order to evaluate their potential application for the follow-up of patients treated with a cardiac resynchronization therapy (CRT). A methodology combining spatiotemporal fuzzy coding and multiple correspondence analysis (MCA) is applied in order to: 1) reduce the dimensionality of the data and provide new synthetic indexes based on the "factorial axes" obtained from MCA; 2) interpret these factorial axes in physiological terms; and 3) analyze the evolution of the patient's status by projecting the acquired data into the plane formed by the first two factorial axes named "factorial plane." In order to classify the different evolution patterns, a new similarity measure is proposed and validated on the simulated datasets, and then, used to cluster observed data from 41 CRT patients. The obtained clusters are compared with the annotations on each patient's medical record. Two areas on the factorial plane are identified, one being correlated with a health degradation of patients and the other with a stable clinical state.     

Detection and mapping of oxygen in silicon wafers by scanning infrared absorption

Scanning Infrared Absorption (S.I.R.A.) setup was carried out for investigating and mapping of microdefects distribution in Czochralski silicon wafers. Using CO₂ laser, this non destructive, non contact test method allows transmitted beam local attenuation from oxygen precipitates to be determined. Transmitted intensity I_t maps from peak height of the 1080 cm^?1 absorption band were obtained. An inhomogeneous initial oxygen distribution is found in as-grown samples. The samples were then submitted to preannealing at 750°C for 16 hours, followed by annealing at 900°C for 24 hours. The obtained I_t fluctuations mapping depicts a ring-shaped distribution of oxygen precipitates.     

Segmentation of video sequences and rate control

This paper deals with the relation between segmentation for coding and rate control. The efficiency of a segmentation-based coding scheme heavily relies on this step that defines how many and which regions have to be segmented. In this paper, we show that this problem can be formulated as a rate/distortion problem. The proposed solution not only controls the segmentation, but also defines the coding strategy to be used in each region. Together with the general approach, several simplified versions of the segmentation control are proposed and discussed.