Interlayer Magnetic Frustration in Quasi-stoichiometric Li1-xNi1+xO2

Susceptibility, high-field magnetization and submillimeter wave electron spin resonance measurements of layered quasi-stoichiometric Li1-xNi1+xO2 are reported and compared to isomorphic NaNiO2. A new mechanism of magnetic frustration induced by the excess Ni ions always present in the Li layers is proposed. We finally comment on the possible realization of an orbital liquid state in this controversial compound.Comment: 4 pages, 5 figures, submitted to Phys.Rev.B, Rapid Com

Cognitive Function in Patients Undergoing Arthroplasty: The Implications for Informed Consent

Obtaining informed consent for an operation is a fundamental daily interaction between orthopaedic surgeon and patient. It is based on a patient's capacity to understand and retain information about the proposed procedure, the potential consequences of having it, and the alternative options available. We used validated tests of memory on 59 patients undergoing lower limb arthroplasty to assess how well they learned and recalled information about their planned procedure. All patients showed an ability to learn new material; however, younger age and higher educational achievement correlated with better performance. These results have serious implications for orthopaedic surgeons discussing planned procedures. They identify groups of patients who may require enhanced methods of communicating the objectives, risks, and alternatives to surgery. Further research is necessary to assess interventions to improve communication prior to surgery

Recursive internetwork architecture, investigating RINA as an alternative to TCP/IP (IRATI)

Driven by the requirements of the emerging applications and networks, the Internet has become an architectural patchwork of growing complexity which strains to cope with the changes. Moore’s law prevented us from recognising that the problem does not hide in the high demands of today’s applications but lies in the flaws of the Internet’s original design. The Internet needs to move beyond TCP/IP to prosper in the long term, TCP/IP has outlived its usefulness. The Recursive InterNetwork Architecture (RINA) is a new Internetwork architecture whose fundamental principle is that networking is only interprocess communication (IPC). RINA reconstructs the overall structure of the Internet, forming a model that comprises a single repeating layer, the DIF (Distributed IPC Facility), which is the minimal set of components required to allow distributed IPC between application processes. RINA supports inherently and without the need of extra mechanisms mobility, multi-homing and Quality of Service, provides a secure and configurable environment, motivates for a more competitive marketplace and allows for a seamless adoption. RINA is the best choice for the next generation networks due to its sound theory, simplicity and the features it enables. IRATI’s goal is to achieve further exploration of this new architecture. IRATI will advance the state of the art of RINA towards an architecture reference model and specifcations that are closer to enable implementations deployable in production scenarios. The design and implemention of a RINA prototype on top of Ethernet will permit the experimentation and evaluation of RINA in comparison to TCP/IP. IRATI will use the OFELIA testbed to carry on its experimental activities. Both projects will benefit from the collaboration. IRATI will gain access to a large-scale testbed with a controlled network while OFELIA will get a unique use-case to validate the facility: experimentation of a non-IP based Internet

Quantitative features of multifractal subtleties in time series

Based on the Multifractal Detrended Fluctuation Analysis (MFDFA) and on the Wavelet Transform Modulus Maxima (WTMM) methods we investigate the origin of multifractality in the time series. Series fluctuating according to a qGaussian distribution, both uncorrelated and correlated in time, are used. For the uncorrelated series at the border (q=5/3) between the Gaussian and the Levy basins of attraction asymptotically we find a phase-like transition between monofractal and bifractal characteristics. This indicates that these may solely be the specific nonlinear temporal correlations that organize the series into a genuine multifractal hierarchy. For analyzing various features of multifractality due to such correlations, we use the model series generated from the binomial cascade as well as empirical series. Then, within the temporal ranges of well developed power-law correlations we find a fast convergence in all multifractal measures. Besides of its practical significance this fact may reflect another manifestation of a conjectured q-generalized Central Limit Theorem

Infusion Micro-Pump Development Using MEMS Technology

International audienceDiabetes is a chronic condition that occurs when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin it produces. People having type 1 diabetes require insulin (10% of all diabetics). People with type 2 diabetes can be treated with oral medication, but may also require insulin; 10% of all type 2 diabetics require insulin. Among the actual different methods to administer insulin (syringes, pens and conventional infusion pumps) a possibility to increase infuser performances is offered by the utilization of silicon based MEMS pumps (Micro- Electro Mechanical Systems). The main two pump families are classified as mechanical and non-mechanical pumps. The former contains check-valve, peristaltic, rectification without valves and rotary ones (“Displacement Pumps”) or Ultrasonic and Centrifugal (“Dynamic Pumps”); the latter consists in Pressure, Concentration, Electrical Potential gradients and Magnetic Potential micro-pumps. The micro-pump described here is an electro-mechanical device actuated with a piezoelectric-element and based on MEMS technology, able to minimize size and costs, offering a high precision pharmacological dispense. Three slices are bonded to reach the final results: top and bottom caps and an intermediate SOI. In case of anodic bonding, top and bottom caps are constituted of micromachined borophosphosilicate wafers, whereas in case of metallic bonding three silicon slices are used. The paper deals with the fabrication evolution of the device according to the different items that had to be faced during development: design, fluidic, mechanical and electrical simulations and characterization, safety requirements and final testing. Built-in reliability is ensured by two inner sensors able to detect any occlusion or malfunctioning and informing so the patient. The result is a compact, core pump chip that can deliver from 0.02 Units of insulin up to 3.6 Units per minute with accuracy better than 5%