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Världen är föränderlig. För att kunna överleva måste allt liv kunna anpassa sig till rådande förhållanden. För cellen, livets minsta enhet, sker detta bland annat genom reglering av produktionstakten av proteiner, vilka är de molekyler som utför de flesta grundläggande funktioner. En speciell klass av proteiner utgörs av så kallade transkriptionsfaktorer. Dessa slår av eller på en gens produktion Living organisms can be viewed as complex biological machines. In order to function, they must regulate their internal mechanism to do the right thing, at the right time, and in the right amount. Part of this regulation is encoded in gene regulatory networks. These are built up of genes which produce special proteins (transcription factors, tf) that regulate other tf-producing genes. Thus a networ

Since the mid-2000s, Russia has increased its efforts to strengthen the legal rights of children and to improve the systems of social assistance to vulnerable families in in line with the UN Convention of the Rights of the Child. The reform drive has met fierce resistance by a grassroots mobilization in defence of ‘traditional Russian family values’. Child rights are conceived of as weapons in a W

In this chapter I propose a social constructionist perspective on public relations, and will particularly focus on crisis communication as an important sub-field, with inspiration from the American sociologist Peter L. Berger. Berger is most well-known for the book The Social Construction of Reality (1966), co-authored with the German sociologist Thomas Luckmann. This book has had a fundamental im

While previous research has advocated the use of online sales channels as a driver for international expansion, the nature of the relationship between e-commerce and international sales is still unexplored. The purpose of this paper is to create a parsimonious model where we investigate whether, and to what extent, strategies pertaining to the geographical scope of international operations moderat

The codification of canon law in the twelfth and thirteenth centuries occurred at the same time as important changes in pastoral practice. This article deals with changes in the practice of baptism that are tied to changes in canonical regulations.Canon law makes a fundamental distinction between solemn baptism and emergency baptism. While emergency baptisms could take place anywhere and at any ti

Experimental results for Na and K deposited at 100 K on the A1(100) surface using low-energy electron diffraction and high-resolution core-level spectroscopy are presented. Our results show that from a coverage of 0.20 monolayers (ML), Na condenses into dense islands with a local Na coverage of 0.50 ML. In the case of K, the overlayer condenses into islands at a coverage of 0.18 ML, with a local c

Thin overlayers of Na, K. Rb, and Cs on different sp-metal substrates have been investigated using photo-electron spectroscopy. The alkali core levels show clearly resolved binding-energy shifts between the surface layer, the intermediate layer(s), and the interface layer. The magnitude of these shifts depends on sp metal and on alkali metal. The layer-resolved core-level binding-energy shifts are

The origin of fine structure in the core-level photoemission spectra of the C2H4, C2D4, C2H3 and C2D3 molecules chemisorbed on Rh(111) is probed in a careful high-resolution study showing that this structure arises from internal molecular vibrations rather than from other chemically-shifted carbon atoms. It is shown by comparison of the adsorbate and gas-phase spectra that the underlying features

High resolution photoemission applied to the C 1s and Rh 3d core levels has been used to investigate the adsorption sites at low temperature of CO on the Rh(111) single crystal surface as a function of CO coverage. Two different sites are found to be occupied by the CO molecules. At coverages up to 0.5 monolayers the majority of the molecules are found to adsorb in on-top sites whereas at higher c

The electronic structure of Ba0.6K0.4BiO3-y single crystals has been studied using a scanning photoelectron microscope with a lateral resolution in the one micrometer range. It is possible to change the oxygen content (y) and convert the surface from the metallic to the dielectric state presumably by breaking the Bi-O bonds by using the focused zero-order light to irradiate the sample surface. The

The influence on O 2p holes in single crystalline Bi2Sr2CaCu2O8 upon the interface formation to Cu, Ag and Au has been studied by O K edge X-ray absorption measurements. It was found that Cu reduces the amount of doping induced O 2p holes significantly in the vicinity of the interface, whereas Ag and Au gave a much smaller reduction of these states. Photoemission spectra confirmed previous finding

Semiconducting Ba0.9K0.1BiO3 and superconducting Ba0.6K0.4BiO3 single crystals cleaved in situ have been studied by core level and valence band photoelectron spectroscopy and O K edge x-ray absorption spectroscopy. It was found that the general shape of the valence band spectrum agrees with the shape predicted by band structure calculations, but the intensity near the Fermi level was lower in the

The O 1s core level of three different Bi-Sr-Ca-Cu-O superconductors has been studied by means of high-resolution x-ray-photoelectron spectroscopy (XPS) and x-ray-absorption spectroscopy (XAS). The O 1s XPS spectra could be decomposed into three components that were unambiguously assigned to the emission from the three different oxide layers in the crystal structure. These are, in order of increas

Alkali-metal-induced satellite peaks associated with the K 3p and Al 2p core levels have been measured with photoemission for K/Al(111) and K/Al(100) under both low- and room-temperature preparation conditions. For low-temperature deposition we observedddd loss peaks in good agreement with electron-energy-loss spectroscopy studies of analogous systems which we assign to the excitation of collectiv

For soft x-ray fluorescence spectroscopy with selective energy excitation, it is desirable to have maximum flux at moderate resolution. A plane grating monochromator with varied line spacing can be used in the convergent beam of an ellipsoidal focusing mirror to provide moderate resolution with a large collection angle and minimum number of reflecting surfaces. We determine the design parameters f

Insertion devices on the third-generation 1.5 GeV electron storage ring MAX II will subject the grazing incidence mirrors and gratings of new soft x-ray beamlines to high thermal loads. These thermal loads will cause distortion in the optical surfaces which can be reduced to acceptable levels by the proper choice of substrate material and cooling. A finite element analysis of the temperature varia

The performance of a scanning photoelectron microscope at the MAX I storage ring in Lund is presented. The microscope utilizes undulator radiation in the energy range 15-150 eV and is comprised of a plane-grating monochromator with a Kirkpatrick-Baez objective and a gracing incidence ellipsoidal focusing mirror. The instrument with its high photon flux, 109-1010 photons/s, and narrow bandwidth, be

High resolution core level photoemission measurements are reported of the binding energy shifts of the 3d core level of Mo, Rh and Pd atoms in interfaces between these 4d metals and alkali metals. The core level binding energies of the interface 4d atoms are found to be almost equal to those of the clean surface atoms for Mo and Rh. For Pd a large alkali induced shift towards higher binding energy

Core level binding energy shifts from approximately three layers of different alkali metals deposited on Pd(111), Pd(100), Rh (111), and Rh (110) are presented in order to demonstrate how the packing of the substrate surface affects the layer-resolved alkali core level binding energy shifts. It is found that a more open surface induces a larger alkali core level binding energy shift. It is shown t