Trajectories of maternal depressive symptoms, maternal sensitivity, and children's functioning at school entry.

Using data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, the authors modeled trajectories of maternal depressive symptoms from infant age 1 month to 7 years. The authors identified 6 trajectories of maternal depressive symptoms: high-chronic, moderate-increasing, high-decreasing, intermittent, moderate-stable, and low-stable. Women on these depression trajectories varied in sociodemographic risk and in changes in observed maternal sensitivity over time. Maternal sensitivity was generally higher and increased when depressive symptoms were low; sensitivity was lower and decreased when depressive symptoms were either high or increasing. Child outcomes at 1st grade were examined by trajectory group. The authors discuss the complexity of disentangling maternal symptoms from maternal sensitivity and sociodemographic risk when predicting children's functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation between shear banding and penetration characteristics of conventional tungsten alloys

The dynamic compression failure and ballistic penetration characteristics of conventional tungsten alloys similar in strength were investigated. Dynamic compression failure properties were generated with a symmetric Taylor test technique and penetration characteristics were obtained with 44 mm kinetic penetrators against an 300 HB hardness steel target at 1400 m/s. From shear crack length data generated with Taylor specimens impacted at different impact speeds a critical speed characterizing shear band initiation was deduced. The critical equivalent plastic strain at shear band initiation sites, obtained from the numerical simulation of the Taylor test at the critical impact speed, was found to decrease with the increase of the penetration performance. These results reinforce the argument that shear band formation is a failure mechanism associated with the erosion process for conventional tungsten alloys.     

Postwar Science in Divided Europe: A Continuing Cooperation

This paper is devoted to an outline of certain aspects of international scientific cooperation and exchange between Eastern and Western European countries from 1950 to 1989, with an emphasis on mathematics, biochemistry and neuroscience.     

Tailoring Dielectric Properties of Multilayer Composites Using Spark Plasma Sintering

A straightforward and simple way to produce well-densified ferroelectric ceramic composites with a full control of both architecture and properties using spark plasma sintering (SPS) is proposed. SPS main outcome is indeed to obtain high densification at relatively low temperatures and short treatment times thus limiting interdiffusion in multimaterials. Ferroelectric/dielectric (BST64/MgO/BST64) multilayer ceramic densified at 97% was obtained, with unmodified Curie temperature, a stack dielectric constant reaching 600, and dielectric losses dropping down to 0.5%, at room-temperature. This result ascertains SPS as a relevant tool for the design of functional materials with tailored properties.     

Use of hydroxytelechelic cis-1,4-polyisoprene (HTPI) in the synthesis of polyurethanes (PUs). Part 1. Influence of molecular weight and chemical modification of HTPI on the mechanical and thermal properties of PUs

New telechelic cis-1,4-polyisoprene oligomers bearing an hydroxyl group at the end of the polyisoprene backbone and possessing controlled molecular weights were used as soft segments in the elaboration of polyurethane elastomers. Besides, the well defined hydroxytelechelic cis-1,4-polyisoprene (HTPI) structure obtained through a controlled methodology, was chemically modified leading to hydrogenated and epoxidized oligomers based polyurethanes. The influence of the structural changes of these precursors on the polyurethanes properties have been studied. Thus, mechanical parameters as well as glass transition and mechanical transition temperature measurements indicated an increase in PUs hardness when the length of soft segment decreases and when the degree of epoxidized and hydrogenated isoprenic moieties increases. Moreover, based on thermogravimetric analysis (TGA), a linear relationship was established between the weight loss in the urethane stage degradation and the amount of hard segments in the PUs. Otherwise, the hydrogenated soft segments were found more thermally stable than the epoxidized and the non modified ones. By comparison with similar investigations developed from commercial oligodienes (PBHT R20 LM^® and EPOL^®), this study mainly showed that the PUs based on hydrogenated hydroxytelechelic cis-1,4-polyisoprenes were more thermally stable and softer than the EPOL^® based analogues.     

Hypoglycaemia‐free artificial pancreas project

Driving blood glycaemia from hyperglycaemia to euglycaemia as fast as possible while avoiding hypoglycaemia is a major problem for decades for type‐1 diabetes and is solved in this study. A control algorithm is designed that guaranties hypoglycaemia avoidance for the first time both from the theory of positive systems point of view and from the most pragmatic clinical practice. The solution consists of a state feedback control law that computes the required hyperglycaemia correction bolus in real‐time to safely steer glycaemia to the target. A rigorous proof is given that shows that the control‐law respects the positivity of the control and of the glucose concentration error: as a result, no hypoglycaemic episode occurs. The so‐called hypo‐free strategy control is tested with all the UVA/Padova T1DM simulator patients (i.e. ten adults, ten adolescents, and ten children) during a fasting‐night scenario and in a hybrid closed‐loop scenario including three meals. The theoretical results are assessed by the simulations on a large cohort of virtual patients and encourage clinical trials.Inspec keywords: biochemistry, medical control systems, blood, diseases, medical computing, closed loop systems, biomedical equipment, state feedback, patient treatment, patient monitoring, biomedical measurement, physiological models, sugarOther keywords: fasting‐night scenario, hybrid closed‐loop scenario, hypoglycaemia‐free artificial pancreas project, blood glycaemia, euglycaemia, type‐1 diabetes, control algorithm, guaranties hypoglycaemia avoidance, pragmatic clinical practice, state feedback control law, required hyperglycaemia correction bolus, rigorous proof, control‐law, glucose concentration error, hypo‐free strategy control     

Energy Aware Signal Processing for Software Defined Radio Baseband Implementation

The fast pacing diversity and evolution of wireless communications require a wide variety of baseband implementations within a short time-to-market. Besides, the exponentially increased design complexity and design cost of deep sub-micron silicon highly desire the designs to be reused as much as possible. This yields an increasing demand for reconfigurable/ programmable baseband solutions. Implementing all baseband functionalities on programmable architectures, as foreseen in the tier-2 SDR, will become necessary in the future. However, the energy efficiency of SDR baseband platforms is a major concern. This brings a challenging gap that is continuously broadened by the exploding baseband complexity. We advocate a system level approach to bridge the gap. Specifically, we fully leverage the advantages (programmability) of SDR platforms to compensate its disadvantages (energy efficiency). Highly flexible and dynamic baseband signal processing algorithms are designed and implemented to exploit the abundant dynamics in the environment and the user requirement. Instead of always performing the best effort, the baseband can dynamically and autonomously adjust its work load to optimize the average energy consumption. In this paper, we will introduce such baseband signal processing techniques optimized for SDR implementations. The methodology and design steps will be presented together with 3 representative case studies in HSDPA, WiMAX and 3GPP LTE.