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A 2.4-to-5.3GHz Dual-Core CMOS VCO with Concentric 8-Shaped Coils

Despite recent attempts to relax the phase-noise demands on voltage-controlled oscillators (VCOs) for cellular communications [1], mainstream radios require harmonic VCOs capable of a very low phase noise with moderate power consumption, associated to a large tuning range (TR) and a high insensitivity to interfering signals. Ideally, the TR should be in excess of one octave, since this allows the

High population variability and source-sink dynamics in a solitary bee species

Although solitary bees are considered to play key roles in ecosystem functions, surprisingly few studies have explored their population dynamics. We investigated the population dynamics of a rare, declining, solitary bee (Andrena humilis) in a landscape of 80 km 2 in southern Sweden from 2003 to 2011. Only one population was persistent throughout all years studied; most likely this population supp

Process performance in lignin separation from softwood black liquor by membrane filtration

Black liquor is a side-stream in the production of kraft pulp. The extraction of lignin and hemicelluloses from black liquor would reduce the load on the recovery boiler and give valuable by-products. Lignin was separated from black liquor by membrane filtration, using one ceramic and three polymeric nanofiltration membranes, with molecular weight cut-offs in the range of 200 Da to 1 kDa. Ultrafil

A multiple representation data structure for dynamic visualisation of generalised 3D city models

In this paper, a novel multiple representation data structure for dynamic visualisation of 3D city models, called CityTree, is proposed. To create a CityTree, the ground plans of the buildings are generated and simplified. Then, the buildings are divided into clusters by the road network and one CityTree is created for each cluster. The leaf nodes of the CityTree represent the original 3D objects

alpha-Synuclein propagates from mouse brain to grafted dopaminergic neurons and seeds aggregation in cultured human cells

Post-mortem analyses of brains from patients with Parkinson disease who received fetal mesencephalic transplants show that alpha-synuclein-containing (alpha-syn-containing) Lewy bodies gradually appear in grafted neurons. Here, we explored whether intercellular transfer of alpha-syn from host to graft, followed by seeding of alpha-syn aggregation in recipient neurons, can contribute to this phenom

An integrated approach towards sustainable entrepreneurship - Experience from the TEST project in transitional economies

The challenge how to assist enterprises more effectively within industrial hot spots of the Danube River Basin in order to meet environmental standards while enhancing their competitiveness was addressed by the project Transfer of Environmentally Sound Technology (TEST). New, integrated approaches were developed and found to be effective in fostering organizational learning and helping to ensure i

The Bergman projection on vector-valued L-2-spaces with operator-valued weights

We characterize the boundedness of the Bergman projection on vector-valued L-2-spaces with operator-valued weights in terms of an appropriate condition of Muckenhoupt-type for the weight. This contrasts with the situation en Hardy spaces, where such characterizations are only possible in the finite-dimensional case. (C) 2011 Elsevier Inc. All rights reserved.

Adding particle collisions to the formation of asteroids and Kuiper belt objects via streaming instabilities

Modelling the formation of super-km-sized planetesimals by gravitational collapse of regions overdense in small particles requires numerical algorithms capable of handling simultaneously hydrodynamics, particle dynamics and particle collisions. While the initial phases of radial contraction are dictated by drag forces and gravity, particle collisions become gradually more significant as filaments

Commutants and Centers in a 6-Parameter Family of Quadratically Linked Quantum Plane Algebras

We consider a family of associative algebras, defined as the quotient of a free algebra with the ideal generated by a set of multi-parameter deformed commutation relations between four generators consisting of five quantum plane relations between pairs of generators and one sub-quadratic relation inter-linking all four generators. For generic parameter vectors, the center and the commutants of the

Enclosure-Induced Interference Effects in a Miniaturized Sidescan Sonar

On, for instance, the miniaturized submersible explorer, Deeper Access, Deeper Understanding (DADU), only 20 cm in length and 5 cm in diameter, the sidescan sonar needs to be tightly mounted in the hull. Finite element analysis (FEA) as well as physical measurements were used to investigate the effects of beam interaction with acoustically nearby rigid boundaries. Computer simulations showed the f

Asymmetric InGaAs MOSFETs with InGaAs source and InP drain

Asymmetric In0.53Ga0.47As MOSFETs with different regrown contacts at source (In0.53Ga0.47As) and drain (InP) have been developed. By introducing a wider bandgap material, InP as drain electrode, higher self-gain g(m)/g(d) has been obtained with reduced output conductance g(d) and improved break-down voltage V-bd. For L-g=100nm, a high oscillation frequency f(max)= 270GHz has been obtained using an

Between love and fear - determinants of sexual behavior among Ugandan university students

Background: More than half of all new HIV infections in sub-Saharan African countries, including Uganda, occur among young people between the ages of 15 and 24, the most sexually active period of their lives. Understanding the contextual determinants of sexual behavior in this group is crucial in combating the pandemic. Aim: The overall aim of this study was to assess the impact of demographic, r

The Czechoslovak Iron and Steel Industry: Productive efficiency under state socialism in a comparative perspective

Czechoslovak productive efficiency of the iron and steel sector fluctuated below the energy efficiency frontier. Until early 1970s, the country's iron sector was one of the least efficient ones in our sample. It was, however, during the decades of 1970s and 1980s that efficiency measures were adopted and the energy efficiency of the Czechoslovak iron and steel sector increased significantly to, de

A thermomechanical constitutive model for cemented granular materials with quantifiable internal variables. Part II - Validation and localization analysis

We study the mechanical failure of cemented granular materials (e.g., sandstones) using a constitutive model based on breakage mechanics for grain crushing and damage mechanics for cement fracture. The theoretical aspects of this model are presented in Part I: Tengattini et al. (2014), A thermomechanical constitutive model for cemented granular materials with quantifiable internal variables, Part

Enterococcus faecalis Infection Causes Inflammation, Intracellular Oxphos-Independent ROS Production, and DNA Damage in Human Gastric Cancer Cells

Background: Achlorhydria caused by e.g. atrophic gastritis allows for bacterial overgrowth, which induces chronic inflammation and damage to the mucosal cells of infected individuals driving gastric malignancies and cancer. Enterococcus faecalis (E. faecalis) can colonize achlohydric stomachs and we therefore wanted to study the impact of E. faecalis infection on inflammatory response, reactive ox

Exploring the Impact of Contrasting Cases in Text and Picture Processing

Abstract Multimodal learning materials are frequently met in education assuming enhanced learning outcomes. This study examined whether contrasts in such materials are likely to support reading comprehension for all readers. Young adults (n=46) met either text-only or text+picture material. Participants (19 with low phonological awareness [PA] and 27 controls with high PA) thereafter answered open