| 1. |
- Carlson, Stefan, et al.
(författare)
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XAFS experiments at beamline I811, MAX-lab synchrotron source, Sweden
- 2006
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Ingår i: Journal of Synchrotron Radiation. - 1600-5775. ; 13, s. 359-364
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Tidskriftsartikel (refereegranskat)abstract
- A description of a new facility for X-ray absorption spectroscopy at the materials science beamline, I811, at MAX-lab synchrotron source, Lund, Sweden, is given. The beamline is based on a superconducting multipole wiggler source inserted in a straight section of the 1.5 GeV MAX-II ring. X-rays in the energy range 2.4- 12 keV are extracted by a standard optical scheme consisting of a vertical collimating first mirror, double-crystal monochromator, and a second vertically focusing mirror. The second monochromator crystal provides sagittal focusing. The total flux impinging on the sample at 9 keV is 5 x 10(11) photons s(-1), for a minimum beam spot of 0.5 mm x 0.5 mm. The beamline has facilities for experiments in transmission, fluorescence and total-electronyield mode and experiments have been performed by international research groups on a wide range of materials, such as dilute systems with metal concentrations below 10 p. p. m.
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| 2. |
- Salford, Leif, et al.
(författare)
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The mammalian brain in the electromagnetic fields designed by man with special reference to blood-brain barrier function, neuronal damage and possible physical mechanisms
- 2008
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Ingår i: PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT. - 0375-9687. ; :173, s. 283-309
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Konferensbidrag (refereegranskat)abstract
- Life oil earth was formed during billions of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation, atmospheric electric fields and the terrestrial magnetism. The Schumann resonances at 7.4 Hz are all example of oscillations possibly important for life.(1)) The existing organisms are created to function in harmony with these forces. However, in the late 19th century mankind introduced the use of electricity, in the early 20th century long-wave radio and in the 1940-ies short-wave radio. High frequency RF was introduced in the 50-ies as FM and television and during the very last decades, microwaves of the modern communication society spread around the world. Today, however, one third of the world's population is owner of the microwave-producing mobile phones and an even larger number is exposed to the cordless RF emitting systems. To what; extent are all living organisms affected by these, almost everywhere present radio frequency fields? And what will be the effects of many years of continuing exposure? Since 1989 Our group has studied the effects upon the mammalian blood-brain barrier (BBB) in rats by non-thermal radio frequency electromagnetic fields (RF-EMF). These have been shown to cause significantly increased leak-age of the rats' own blood albumin through the BBB of exposed rats, at energy levels of 1W/kg and below, as compared to non-exposed animals in a total series of about two thousand animals.(2)-6)) One remarkable observation is the fact that the lowest energy levels, with whole-body average power densities below 10mW/kg, give rise to the most pronounced albumin leakage. If mobile communication, even at extremely low energy levels, causes the users' own albumin to leak out through the BBB, also other unwanted and toxic molecules in the blood, may leak into the brain tissue and concentrate in and damage the neurons and glial cells of the brain. In later studies we have shown that a 2-h exposure to GSM 915 MHz, at non-thermal SAB-values of 0.2, 2 and 200 mW/kg, gives rise to significant neuronal damage, seen not only 50 days after the exposure 7) but also after 28 days but not after 14 days. Albumin extravasations and uptake into neurons was enhanced after 14 clays, but not after 28.(8)) in our continued research, also the non-thermal effects oil tissue structure and memory function of long-term exposure for 13 months are studied.(9)) We have also performed microarray analysis of brains from rats exposed to short term GSM both at 1,800 MHz and at 900MHz and have found significant effects upon gene expression of membrane associated genes as compared to control animals.(10),11)) Most of our findings support that living organisms are affected by the non-thermal radio frequency fields. Some other Studies agree while others find no effects. The mechanisms by which the EMFs may alter BBB permeability are not Well Understood. At low field strengths, the effects on body temperature are negligible and thus heating effects are not involved. A change in the physicochemical characteristics of membranes has been suggested as a cause.(12)) We have performed experiments to verify a quantum mechanical model for interaction with protein-bound ions. Our results show that controlled frequency and amplitude of ELF EM fields upon spinach plasma vesicles can steer transport over the membrane.(13)) This may be a first proof of a resonance phenomenon where appropriate levels of frequency and amplitude in the right combination have the potency to communicate with the biology of membranes and transport systems. Our study has prompted Lis to elaborate on magnetic resonance models; the Ion Cyclotron Resonance (ICR) model and the Ion Parametric Resonance (IPR) Model in an attempt to explain the occurrence of resonance frequencies. This is extensively described here under the heading: Mechanisms behind the effects of electromagnetical fields upon biology. We also bring forward the concept of solitons being active in membranes and DNA/RNA-transcription as a, possible mean to understand and prove the biological effects of EMF. The Nishinomiya-Yukawa International and Interdisciplinary Symposium 2007 raised the question: What is Life? An obvious and simple answer could be: It is DNA! The DNA strand can be looked upon as an antenna resonating in the microwave band 6GHz with its harmonics and subharmonics.(14)-18)) If this holds true, the dramatic situation might exist, that all living organisms have a receptor for the newly constructed and world-wide man-made microvaves, leading to a direct effect upon the function of DNA - in concordance with our experimental findings! Our generation invented the microwave emitters. We now have in imperative obligation to further investigate the links between EMF and biology in order to prevent possible detrimental effects of the microwaves.
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| 3. |
- Shen, Z, et al.
(författare)
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Chondroadherin expression changes in skeletal development
- 1998
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Ingår i: The Biochemical journal. - 0264-6021. ; 330, s. 549-557
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Tidskriftsartikel (refereegranskat)abstract
- Chondroadherin is a cartilage protein with cell binding properties. The expression of chondroadherin was studied in rat tissues and during postnatal femoral head development. For design of oligonucleotide probes and primers a 1664 bp, full length, rat chondroadherin cDNA was isolated from a rat chondrosarcoma library and sequenced. Northern blot analysis showed chondroadherin mRNA to be present in femoral head and rib cartilage, as well as in tendon. More sensitive reverse-transcriptase PCR additionally identified the mRNA in calvaria, long bone and bone marrow. Localization of chondroadherin by immunocytochemistry in the developing femoral head from postnatal day 14 to day 60 showed presence of the protein in cartilaginous regions. With increasing age a very distinct localization of chondroadherin was seen in the territorial matrix around late proliferative cells in the growth plate as well as in the developing articular cartilage in the maturing femoral head. Localization of chondroadherin mRNA by in situ hybridization was in agreement with immunocytochemistry with strong hybridization signals in late proliferative cells in the growth plate. In the articular cartilage the expression was restricted to cells in the lower regions. A three-fold increase of cartilage chondroadherin content in the growing femoral head was demonstrated by Western blot analysis. The high expression of this cell binding protein in a dynamic region of cartilage suggests an important role for chondroadherin in the regulation of chondrocyte growth and proliferation.
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| 4. |
- Thiagarajan, Balasubramanian, et al.
(författare)
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The Normal Incidence Monochromator Beamline I3 on MAX III
- 2010
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Ingår i: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. ; 1234, s. 661-664
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Konferensbidrag (refereegranskat)abstract
- On the 700 MeV MAX III ring at MAX-lab, a 6.65 m off-axis eagle type monochromator beamline has recently been commissioned. The beamline is sourced by an apple type variable polarization undulator. The energy range of the beamline is 4.6-50 eV and the resolving power achieved is more than 100,000. There are two branch lines, one for angle and spin resolved photoemission studies from solids and the other for gas phase and luminescence experiments. We present the design and performance of the beamline.
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| 5. |
- Ursby, Thomas, et al.
(författare)
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The new macromolecular crystallography stations at MAX-lab: The MAD station
- 2004
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Ingår i: AIP Conference Proceedings. - 0094-243X .- 1551-7616. ; 705, s. 1241-1244
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Konferensbidrag (refereegranskat)abstract
- A new beamline, Cassiopeia, at MAX II is about to come into operation. It consists of an energy-tunable station and four side stations intended for macromolecular crystallography. The X-ray source is a 3.5 T superconducting multipole wiggler installed in the 1.5 GeV MAX II storage ring. The energy-tunable station use grazing incidence Rh-coated silicon mirrors and an internally water-cooled Si(111) double-crystal monochromator while the four side stations use bent diamond and germanium monochromators and multilayer mirrors. This paper concentrates on the optics design of the energy-tunable station and also briefly describes other beamline components
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| 6. |
- Westergren, Tomas, et al.
(författare)
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Phosphatidylinositol 4-Kinase Associated with Spinach Plasma Membranes. Isolation and Characterization of Two Distinct Forms
- 1999
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Ingår i: Plant Physiology. - 1532-2548. ; 121:2, s. 507-516
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Tidskriftsartikel (refereegranskat)abstract
- Highly purified plasma membranes from spinach (Spinacia oleracea L.) leaves contained phosphatidylinositol (PtdIns) kinase activity that was firmly associated with the membrane. The enzyme was solubilized by detergent treatment (2% [w/v] Triton X-100) and purified by heparin-Sepharose and Q-Sepharose chromatography. Two enzymically active fractions, QI and QII, both exhibiting PtdIns 4-kinase activity, were resolved and purified 100- to 300-fold over the plasma membrane. QI and QII shared similar high apparent Km values for ATP (approximately 0.45 mM) and PtdIns (approximately 0.2 mM) and were insensitive to inhibition by adenosine. While Mg2+ was the preferred divalent cation, Mn2+ could partly substitute in the reaction catalyzed by the QII enzyme but not in that catalyzed by QI. Mn2+ acted synergistically with suboptimal Mg2+ concentrations to activate not only the QII enzyme, but also to some extent QI. Both enzymes were inhibited by millimolar concentrations of Ca2+ and micromolar concentrations of wortmannin. The apparent molecular mass for QI was 120 kD, which was determined by SDS-PAGE and western blotting using an antibody against a peptide unique for lipid kinases and the binding of 3H-wortmannin, and for QII 65 kD as determined by immunodetection and renaturation of PtdIns kinase activity in the 65-kD region of polyacrylamide gels.
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