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Mechanical Tensioning of High-Strength Aluminum Alloy Friction Stir Welds

The extent to which in-situ global mechanical tensioning (GMT) can be used to modify the residual stress state in friction stir (FS) welds is investigated in this article. Residual stress distributions have been determined by synchrotron X-ray and neutron diffraction for four sets of FS welds in high-strength AA7449-W51 and lithium containing AA2199-T8 aerospace aluminum alloys subjected to a syst

Performance of handheld MIMO terminals in noise- and interference-limited urban macrocellular scenarios

Abstract in UndeterminedMultiple-antenna handheld terminals are an integral part of the latest mobile communication systems, due to the adoption of multiple-input multiple-output (MIMO) technology. In this contribution, MIMO performances of three multiple-antenna configurations for smart phones are investigated in an urban macrocellular environment, based on an extensive MIMO measurement campaign

Ultrafast conductivity in a low-band-gap polyphenylene and fullerene blend studied by terahertz spectroscopy

Time-resolved terahertz spectroscopy and Monte Carlo simulations of charge-carrier motion are used to investigate photoinduced transient conductivity in a blend of a low-band-gap polyphenylene copolymer and fullerene derivative. The optical excitation pulse generates free holes delocalized on polymer chains. We show that these holes exhibit a very high initial mobility as their initial excess ener

Investigation of microcracks in ferroelectric materials by application of a grain--boundary--motivated cohesive law

Ferroelectric materials exhibit a huge potential for engineering applications - ranging from electrical actuators (inverse piezoelectric effect) to sensor technology (direct piezoelectric effect). To give an example, lead zirconate titanate (PZT) is a typical perovskite ion crystal possessing ferroelectric properties. In this contribution, we are particularly interested in the modelling of microcr

Independent replication of a melanoma subtype gene signature and evaluation of its prognostic value and biological correlates in a population cohort.

Development and validation of robust molecular biomarkers has so far been limited in melanoma research. In this paper we used a large population-based cohort to replicate two published gene signatures for melanoma classification. We assessed the signatures prognostic value and explored their biological significance by correlating them with factors known to be associated with survival (vitamin D) o

Komplettering av kärlväxtfloran i Blekinge

Hela 122 nya arter för Blekinge – varav åtta även nya för Sverige – har hittats sedan Blekinges flora kom ut 2006. Lars Fröberg presenterar här den digra fyndlistan.

Ionization Constants pKa of Cardiolipin.

Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to diffe

Evaluation of assimilatory sulphur metabolism in Caldicellulosiruptor saccharolyticus

Caldicellulosiruptor saccharolyticus has gained reputation as being among the best microorganisms to produce H2 due to possession of various appropriate features. The quest to develop an inexpensive cultivation medium led to determine a possible replacement of the expensive component cysteine, i.e. sulphate. C. saccharolyticus assimilated sulphate successfully in absence of a reducing agent withou

Steady water waves with multiple critical layers

We construct small-amplitude periodic water waves with multiple critical layers. In addition to waves with arbitrarily many critical layers and a single crest in each period, multimodal waves with several crests and troughs in each period are found. The setting is that of steady two-dimensional finite-depth gravity water waves with vorticity.

Simple Group Graded Rings and Maximal Commutativity

In this paper we provide necessary and sufficient conditions for strongly group graded rings to be simple. For a strongly group graded ring R the grading group G acts, in a natural way, as automorphisms of the commutant of the neutral component subring R_e in R and of the center of R_e. We show that if R is a strongly G-graded ring where R_e is maximal commutative in R, then R is a simple ring if

A Winged Figure From Uppakra

During excavations at Uppakra in Scania, Sweden, an exceptional copper alloy mount in the shape of a winged human was found. The figure is unique not only in its exquisite craftsmanship, but also in its iconography. It is argued that the mount was made in the loth century AD and that it depicts Wayland the Smith.

Human uniqueness, bodily mimesis and the evolution of language

I argue that an evolutionary adaptation for bodily mimesis, the volitional use of the body as a representational devise, is the “small difference” that gave rise to unique and yet pre-linguistic features of humanity such as (over)imitation, pedagogy, intentional communication and the possibility of a cumulative, representational culture. Furthermore, it is this that made the evolution of language

Katolsk politisk doktrin och sociallära : religionsfrihet och mänskliga rättigheter

The 18th century witnessed profound changes in the political thinking of Western societies regarding the individual, society and the state. The principle of freedom of religion was confirmed in the American Declaration of Independence in 1776 and in the French Declaration of the Rights of Man and of the Citizen in 1789. A guiding principle was that the civic rights of individuals were not to be de

Within-population variation in ejaculate characteristics in a prolonged breeder, Peron's tree frog, Litoria peronii

Sperm number is often a good predictor of success in sperm competition; however, it has become increasingly clear that, for some species, variation in probability of paternity cannot be explained by sperm number alone. Intraspecific variation in ejaculate characteristics, such as the number of viable sperm and sperm longevity, may play an equally important role in determining fertilization success

Interobserver and intraobserver agreement in the evaluation of CT perfusion in ischemic stroke

Knowledge of interrater reliability in the evaluation of perfusion computed tomography (CTP) studies is very limited even though the method is widely used in the workup of acute stroke. The aims of this study were to estimate the inter- and intraolbserver agreement in the evaluation of CTP data and to evaluate the feasibility of the method. The CTP data of 20 consecutive patients (50% were females

Modeling dengue outbreaks

We introduce a dengue model (SEIR) where the human individuals are treated on an individual basis (IBM) while the mosquito population, produced by an independent model, is treated by compartments (SEI). We study the spread of epidemics by the sole action of the mosquito. Exponential, deterministic and experimental distributions for the (human) exposed period are considered in two weather scenarios

Frequent detection of respiratory agents by multiplex PCR on oropharyngeal samples in Swedish school-attending adolescents

Background: Respiratory agents may be detected in the oropharynx of healthy individuals. The extent of this condition and the reasons behind it are largely unknown. The objective of this study was to determine the factors associated with the presence of respiratory agents in the oropharynx of adolescents healthy enough to attend school activities. Methods: On a single day in December, samples from

Wetland development, permafrost history and nutrient cycling inferred from late Holocene peat and lake sediment records in subarctic Sweden

Permafrost in peatlands of subarctic Sweden is presently thawing at accelerated rates, which raises questions about the destiny of stored carbon and nutrients and impacts on adjacent freshwater ecosystems. In this study we use peat and lake sediment records from the Stordalen palsa mire in northern Sweden to address the late Holocene (5,000 cal BP-present) development of the mire as well as relate