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The photon collider at TESLA

High energy photon colliders (gammagamma,gammae) are based on e(-)e(-) linear colliders where high energy photons are produced using Compton scattering of laser light on high energy electrons just before the interaction point. This paper is a part of the Technical Design Report of the linear collider TESLA.(1) Physics program, possible parameters and some technical aspects of the photon collider a

Formation of Rhodium Carbonyl Cluster Thiolates with Concomitant H2 evolution

Reaction of [Rh6(CO)15(NCMe)] with p-thiocresol [(4-Me)C6H4SH] leads to the formation of [Rh2(CO)4(μ-SC6H4CH3)2] as the main product along with a small amount of [Rh6(CO)16]. An approximately 30-fold excess of the thiol is required in order to obtain a good yield of the thiolate-bridged dimer while reaction of [Rh4(CO)12] with an excess of p-thiocresol leads to an apparently clean conversion to th

Quantification, of photosystem I and II in different parts of the thylakoid membrane from spinach

Abstract: Electron paramagnetic resonance (EPR) was used to quantify Photosystem I (PSI) and PSII in vesicles originating from a series of well-defined but different domains of the thylakoid membrane in spinach prepared by non-detergent techniques. Thylakoids from spinach were fragmented by sonication and separated by aqueous polymer two-phase partitioning into vesicles originating from grana and

On the crest of a population wave

Understanding the population highs and lows of periodic outbreaks of insect pests should contribute to more efficient control measures. As Ranta and colleagues discuss in their Perspective, a new modeling approach (Bjørnstad et al.) has accurately predicted the direction and speed of traveling waves of larch budmoth outbreaks, which have defoliated large areas of larch forest in the European Alps.

Naturläkemedel och hormonpreparat ­ potentiell risk för bröstcancerpatienter. Studie kartlägger bruk av medel som kanske motverkar behandlingen

We have studied the use of complimentary alternative medicine (CAM) among 233 consecutive breast cancer patients operated on at the Lund University Hospital, Sweden between 2002 and 2004. Questionnaires were administered preoperatively (n = 233), and again 3-6 months post-operatively (n = 167) and one year after surgery (n = 88). At baseline, 14,5% used CAM, 3-6 months post-operatively 14,4% used Bruket av naturläkemedel och andra faktorer som kan interagera med behandling av bröstcancer kartläggs i en pågående studie hos bröstcancerpatienter i Lund; i artikeln redovisas basdata för 233 patienter. Vid inskrivningen använde totalt 14,5 procent av patienterna naturläkemedel, vid 1-årskontrollen 18,2 procent. Sammanlagt 35 olika preparat användes, varav soja och övriga fytoöstrogener, vitlök,

Older people's use of powered wheelchairs for activity and participation

Objective: The aims of this study were to investigate outcomes of older people's use of powered wheelchairs and risk factors for negative outcomes. Design: The study was a cross-sectional interview-study including 111 powered wheelchair users over 65 years of age. Results: All participants used their powered wheelchair in the summer; nearly all users regarded it as important and found that it gave

Search for single top production via FCNC at LEP at root s=189-208 GeV

A search for single top production (e(+)e(-) --> t (c) over bar) via flavour changing neutral currents (FCNC) was performed using the data taken by the DELPHI detector at LEP2. The data analyzed have been accumulated at center-of-mass energies ranging from 189 to 208 GeV. Limits at 95% confidence level were obtained on the anomalous coupling parameters kappa(gamma) and kappa(Z). (C) 2004 Published

Cerebroelectrical depression following surfactant treatment in preterm neonates

During surfactant treatment of respiratory distress syndrome, 23 premature newborns were investigated with continuous amplitude-integrated electroencephalography (cerebral function monitors). Simultaneously, arterial blood pressure and transcutaneous blood gas values were recorded. A short (less than 10 minutes) but significant decrease in cerebral activity was seen in almost all neonates immediat

Atrial fibrillation--Where do we stand today?

The basic underlying mechanisms behind atrial fibrillation (AF), the most abundant therapy demanding cardiac dysrhythmia, have until recently being largely unknown. Once established, AF is not only self-perpetuating but also self-destructive, prompting rapid treatment against possible initiating mechanisms. Recent observations reveal that the ectopic beats, initiating AF, often originate in the wa

Early enteral supply of lactobacillus and fiber versus selective bowel decontamination: A controlled trial in liver transplant recipients

Background. Early enteral nutrition with solutions containing prebiotics (fiber) and probiotics (Lactobacillus) is suggested to reduce bacterial translocation and minimize the incidence of infections after liver transplantation. Methods. In a prospective, randomized placebo-controlled trial consisting of 95 patients, we compared the incidence of postoperative infections and other complications aft

A Hybrid Phase-based Single Frequency Estimator

The topic of low computational complexity frequency estimation of a single complex sinusoid corrupted by additive white Gaussian noise has received significant attention over the last decades due to the wide applicability of such estimators in a variety of fields. In this letter, we propose a computationally fast and statistically improved hybrid phase-based estimator that outperforms other recent

Measurement of lifetimes by laser-induced fluorescence and determination of transition probabilities of astrophysical interest in NdIII

Selective lifetime measurements by time-resolved laser-induced fluorescence spectroscopy for 5 levels belonging to the 4f(3)5d configuration of doubly ionized neodymium provide a first and useful experimental test of the relativistic Hartree-Fock calculations in this ion of astrophysical interest. As a consequence, the accuracy of the transition probabilities deduced in the present work is well as

The interaction between the ISO tapping machine and lightweight floors

The ISO standard tapping machine, used as an excitation source in rating the impact-sound level of a floor structure, interacts with the floor structure during the hammer impact. Expressions for the force spectrum due to the impact are presented. The 6 dB difference at low frequencies of the force spectrum, evident in measurements, and reasons for it, are discussed. The interaction is investigated

A simple model for the arterial system

We present a simple model for the arterial part of the cardiovascular system, based on Poiseuille flow constrained by the power dissipated into the cells lining the vessels. This, together with the assumption of a volume-filling network, leads to correct predictions for the evolution of vessel radii, vessel lengths and blood pressure in the human arterial system. The model can also be used to find