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Experimental validation of k–ε RANS-CFD on a high-pressure homogenizer valve

Since the emulsification in the High-Pressure Homogenizer (HPH) is controlled by hydrodynamic forces, the turbulent flow field in the valve region is of significant interest. Computational Fluid Dynamics (CFD) simulations have been used for this in many studies. However, there are reasons to question if the utilized turbulence models, with their inherent assumptions and simplifications, could accu

A psychophysical evaluation of haptic controllers: viscosity perception of soft environments

In this paper, human viscosity perception in haptic teleoperation systems is thoroughly analyzed. An accurate perception of viscoelastic environmental properties such as viscosity is a critical ability in several contexts, such as telesurgery, telerehabilitation, telemedicine, and soft-tissue interaction. We study and compare the ability to perceive viscosity from the standpoint of detection and d

Flame stabilization in a supersonic combustor with hydrogen injection upstream of cavity flame holders: experiments and simulations

Experimental observations and numerical simulation were conducted to study the flame characteristics and flame stabilization mechanism in a supersonic combustor with hydrogen injection upstream of cavity flame holders. OH radical distribution of the reacting flowfield was obtained using OH spontaneous emission and OH-PLIF (planar laser-induced fluorescence). The supersonic combustion flowfield wit

Dimensionality reduction of fMRI time series data using locally linear embedding.

OBJECTIVE: Data-driven methods for fMRI analysis are useful, for example, when an a priori model of signal variations is unavailable. However, activation sources are typically assumed to be linearly mixed, although non-linear properties of fMRI data, including resting-state data, have been observed. In this work, the non-linear locally linear embedding (LLE) algorithm is introduced for dimensional

Offshore wind power in Sweden - A qualitative analysis of attitudes with particular focus on opponents

The Swedish Parliament has voted for massive expansion of wind power within the next decade. As in many other countries, the establishment of new wind farms has aroused local opposition. This paper contributes to the literature using a qualitative methodology to analyse attitudes towards wind power. In 2007, we carried out in-depth interviews with 40 stakeholders concerned with two planned nearsho

Beyond the neutron drip line: The unbound oxygen isotopes O-25 and O-26

The very neutron-rich oxygen isotopes O-25 and O-26 are investigated experimentally and theoretically. The unbound states are populated in an experiment performed at the R3B-LAND setup at GSI via proton-knockout reactions from F-26 and F-27 at relativistic energies around 442 and 414 MeV/nucleon, respectively. From the kinematically complete measurement of the decay into O-24 plus one or two neutr

Priorities in emergency obstetric care in Bolivia--maternal mortality and near-miss morbidity in metropolitan La Paz

Objective To document the frequency and causes of maternal mortality and severe (near-miss) morbidity in metropolitan La Paz, Bolivia. Design Facility-based cross-sectional study. Setting Four maternity hospitals in La Paz and El Alto, Bolivia, where free maternal health care is provided through a government-subsidised programme. Population All maternal deaths and women with near-miss morbidity. M

Health Alliance for prudent antibiotic prescribing in patients with respiratory tract infections (HAPPY AUDIT) -impact of a non-randomised multifaceted intervention programme

Background: Excessive use of antibiotics is worldwide the most important reason for development of antimicrobial resistance. As antibiotic resistance may spread across borders, high prevalence countries may serve as a source of bacterial resistance for countries with a low prevalence. Therefore, bacterial resistance is an important issue with a potential serious impact on all countries. Initiative

Continuous-Time Delta-Sigma Modulators for Wireless Communication

The ever increasing data rates in wireless communication require analog to digital converters (ADCs) with greater requirements on speed and accuracy, while being power efficient to prolong battery life. This dissertation contains an introduction to the field and five papers that focus on the continuous-time (CT) Delta-Sigma modulator (DSM) as ADC. Paper I analyses the performance degradation of d

Modeling effect of surface roughness on nanoindentation tests

Surface roughness is a commonly used criterion for characterization of surface quality in a machining operation. In the study of micro-scale mechanical properties of machined surface and cutting tool with nanoindentation, prefect surface finish on the test specimen is often required for the reliable result. However, the prefect surface finish is often difficult to obtain from the machining operati

UV-B-induced DNA damage mediates expression changes of cell cycle regulatory genes in Arabidopsis root tips

Even though a number of studies have shown that UV-B radiation inhibits plant growth and regulates the cell cycle progress, little is known about the molecular and cellular mechanisms. Here, we developed a synchronous root-tip cell system to investigate expression changes of cell cycle marker genes and DNA damage under UV-B radiation. Expression analysis of cell cycle marker genes revealed that G1

Determination of pH or lactate in fetal scalp blood in management of intrapartum fetal distress: randomised controlled multicentre trial

Objective To examine the effectiveness of pH analysis of fetal scalp blood compared with lactate analysis in identifying hypoxia in labour to prevent acidaemia at birth. Design Randomised controlled multicentre trial. Setting Labour wards. Participants Women with a singleton pregnancy, cephalic presentation, gestational age >= 34 weeks, and clinical indication for fetal scalp blood sampling. Inter

Experimental and numerical studies of creasing of paperboard

A laboratory creasing device to capture the most important properties of a commercial rotary creasing tool was designed. Finite element analysis of the creasing of a multiply paperboard in the laboratory crease device was presented. The multiply paperboard was modeled as a multilayered structure with cohesive softening interface model connecting the paperboard plies. The paperboard plies were mode

Bjurkärr – en småländsk bokskog med unika lavar och svampar.

The old beech forest (250–300 yr) at Bjurkärr (core area 30 ha) in the province of Småland, S Sweden, was surveyed for epiphytic lichens of conservation concern in 1993–94. Several rare red-listed lichens were recorded, many with large populations. In 2011 the most endangered lichens were resurveyed due to the incorporation of Bjurkärr in the forthcoming national park of Lake Åsnen. Most species o

Interspecific competition and predation: relative effects on foragers and their densities

Predation and competition are both strong structuring forces in community dynamics, but their relative importance is disputed. In a laboratory experiment, we evaluated the relative importance of competition and predation from juvenile and adult brown trout, respectively, on foraging performance of groups of three stone loaches. We observed loach consumption rate, time spent inactive, and aggressiv