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Popular Abstract in Swedish I ett atomkraftsmikroskop avbildar man ytor och föremål genom att känna av ojämnheter med hjälp av en vass spets. Spetsen har en diameter på ca en tusendel av ett hårstrå. I avhandlingen beskrivs en teknik för hur man med denna extremt vassa spets kan manipulera nanometerstora metall- och halvledar partiklar mellan elektroder på en yta för att bygga elektriska komponentIn this thesis a technique to manipulate nanoparticles with an atomic force microscope (AFM) is presented. Particles in the size range of 5-500 nm could be positioned in arbitrary two-dimensional patterns on different surfaces by mechanically pushing them with the AFM tip. The technique which is material-independent can be applied to any type of nanometer-sized particles or objects that are free t

We minimize the frequency and time occupancy of multicarrier binary linear modulation based on two-dimensional faster than Nyquist (FTN) signaling. FTN analysis provides the asymptotic time-frequency consumption per bit and prolate spheroidal wave analysis minimizes the side lobe occupancy. For both problems, an excellent choice is a Gaussian pulse, with some adjustment of the side lobes.

The enlargement of the European Union provides opportunities for members to be mobile in seeking various forms of permanent and non-permanent employment, particularly temporary work and contract labour. These changing conditions require quick reactions, overcoming soft issues such as language barriers and coping with culture clashes and political issues that could create problems for the worker. W

In April 2001 the new European Standard EN 12975:2000: ''Thermal solar systems and components--Solar Collectors'' was established. With the publication of this European standard all national standards, related to the same topic, have to be withdrawn by the nations of the European Community. Now only one standard for testing solar collectors is valid throughout Europe.This European Standard specifi

Popular Abstract in Swedish Tumörer uppstår då celler i kroppen plötsligt börjar växa och dela sig obehindrat. Tumöromvandlingen är ett resultat av mutationer i cellens gener som kontrollerar hur celler tillväxer och differentieras. Sådana gener kallas för onkgener och suppressorgener. Tumörer som respekterar sin omgivning kallas för benigna men så snart de börjar växa invasivt in i omkringliggandNatural killer (NK) cells and T lymphocytes are the major effector cells that can recognize and kill tumor cells. NK cells have a constitutive cytotoxic activity and kill a wide spectrum of tumor cells while T cells recognize specific tumor antigens and need to be activated through their TCR to differentiate into cytotoxic T lymphocyte (CTL) killers or T helper cells. Interleukin-2 is the principa

Wireless communication using very-large multiple-input multiple-output (MIMO) antennas is a new research field, where base stations are equipped with a very large number of antennas as compared to previously considered systems. In theory, as the number of antennas increases, propagation properties that were random before start to become deterministic. Theoretical investigations with independent id

Popular Abstract in Swedish Under de senaste två decennierna har transplantation av embryonal vävnad från ventrala mesencephalon, mitthjärnan, utvecklats till en möjlig terapi för Parkinson’s sjukdom. Ju bättre transplantatet återställer den dopaminerga neurotransmissionen, desto större blir den motoriska förbättringen hos patienten. Dessvärre dör över 90% av de dopaminerga nervcellerna under tranOver the past two decades, grafting of embryonic nigral tissue has developed into a feasible therapeutic strategy for Parkinson's disease (PD). It has become apparent that the degree of restoration of dopaminergic neurotransmission by the transplanted cells is highly correlated to the symptomatic relief. However, the efficacy of the treatment is still far from optimal: More than 90% of the grafted

Acoustic trapping has been shown to be a gentle way of performing non-contact immobilization of cells and particles in microfluidic systems. Acoustic trapping uses localized ultrasonic standing waves that are created in microfluidic channels, cavities or other small, confined spaces. The standing wave creates a pressure node that attracts and holds particles and cells. Commonly, structures in the

Popular Abstract in Swedish De senaste decenniernas forskning om kemiska reaktionsmekanismer har gett resultat som visat sig användbara bl.a. för förståelsen av förbränningsreaktioner, ozonförstöringen i stratosfären och för utvecklingen av syntesmetoder. En stor utmaning vid undersökningar av reaktionsmekanismer utgör det faktum att även till synes enkla kemiska reaktioner ofta har ett kompliceraThe reaction dynamics of several polyatomic systems have been investigated in solution by femtosecond spectroscopy. Tetranitromethane-naphtalene complexes excited in the charge-transfer band at 400 nm undergo dissociative electron transfer, resulting in three primary products: [naphthalene].+, NO2 and C(NO2)3-. It was shown that this triad is formed within 200 fs. The subsequent competing reaction

In conventional MIMO, propagation conditions are often considered wide-sense stationary over the entire antenna array. In massive MIMO systems, where arrays can span over large physical dimensions, the situation is quite different. For instance, significant variations in signal strength, due to shadowing, can be experienced across a large array. These effects vary with propagation environment in w

Combustion modeling based on a multi-step global reaction mechanism [1] is applied to CFD (Computational Fluid Dynamics) analysis of a scaled swirl-stabilized 4th generation premixed DLE (Dry Low Emission) burner for gas turbines. The flexi-fuel burner consists of a MAIN premixed flame, a premixed PILOT flame and a confined RPL (Rich Pilot Lean) flame. Both steady-state RANS (Reynolds Averaged Nav

DNA shows strong interactions with cationic cosolutes and these have both biological and technological significance. We outline our research on various mixed system of DNA and cationic amphiphiles including the interaction of DNA with simple cationic surfactants as well as the interaction with catanionic mixtures and positively charged catanionic vesicles. An overview from phase behavior to micros

The search for planets around white dwarf stars, and evidence for dynamical instability around them in the form of atmospheric pollution and circumstellar disks, raises questions about the nature of planetary systems that can survive the vicissitudes of the asymptotic giant branch (AGB). We study the competing effects, on planets at several AU from the star, of strong tidal forces arising from the