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Ultrafast study of the photodissociation of bromoiodomethane in acetonitrile upon 266 nm excitation

We studied the A-band photodissociation of bromoiodomethane, CH2BrI, in acetonitrile solution at room temperature by femtosecond pump-probe spectroscopy, Initiated by the 266 nm light, this reaction leads to the CH2Br-I isomer, most likely produced via in-cage recombination of the CH,Br and I photofragments. The isomer is formed vibrationally excited with a time constant of similar to7.5 ps and th

Central projections of sensory innervation of cranial vessels

Primary headaches (e.g. migraine and cluster headache), the symptoms of which is associated with cranial vascular activity, is likely to be dependent on a primary central nervous system dysfunction. To further our understanding of the mechanisms behind primary headaches, we investigated the central projections of sensory nerves from three cranial vessels by tract-tracing techniques. In papers I-I

Serum and bronchial lavage fluid concentrations of IL-8, SLPI, sCD14 and sICAM-1 in patients with COPD and asthma

Background: Airway inflammation is associated with an increased expression and release of inflammatory reactants that regulate processes of cell migration, activation and degranulation. The purpose of this study was to quantify bronchial lavage (BAL) fluid and serum levels of chemokine (IL-8), secretory leukocyte protease inhibitor (SLPI), soluble intracellular adhesion molecules-1 (sICAM-1) and s

Stepwise charge separation from a ruthenium-tyrosine complex to a nanocrystalline TiO2 film

A supramolecular complex composed of Ru(II) tris-bipyridine, tyrosine, and dipicolylamine was synthesized and characterized. This complex was attached to TiO2 nanocrystalline films via ester groups at the Ru(II) chromophore, and photoinduced multistep electron transfer was investigated by laser flash photolysis and electron paramagnetic resonance techniques. Following ultrafast electron injection

Site use by dark-bellied brent geese Branta bernicla bernicla on the Russian tundra as recorded by satellite telemetry: implications for East Atlantic Flyway conservation

In 1999, seven dark-bellied brent geese Branta bemicla bemicla were followed during spring migration from western Europe to Arctic Russia using satellite telemetry. For six of the birds we were also able to monitor their summer stay at the Taymyr Peninsula, and for five birds part of their autumn migration was recorded. In this article, we report on site use during summer and spring/autumn migrati

Inte bara föraren styr

De senaste åren har bjudit på en veritabel revolution beträffande tekniken i fordon. Utvecklingen av kraftfulla, billiga och pålitliga mikroprocessorer har öppnat dörren för avancerad datorbaserad styrning av en mångfald fordonsfunktioner. Mycket av den nya tekniken syns inte på utsidan av fordonen, men innebär väsentliga förbättringar för miljö, säkerhet, ekonomi och bekvämlighet.

The renewables portfolio standard in Texas: an early assessment

Texas has rapidly emerged as one of the leading wind power markets in the United States. This development can be largely traced to a well-designed and carefully implemented renewables portfolio standard (RPS). The RPS is a new policy mechanism that has received increasing attention as an attractive approach to support renewable power generation. Though replacing existing renewable energy policies

Variable-phase-shift-based RF-baseband codesign for MIMO antenna selection

We introduce a novel soft antenna selection approach for multiple antenna systems through a joint design of both RF (radio frequency) and baseband signal processing. When only a limited number of frequency converters are available, conventional antenna selection schemes show severe performance degradation in most fading channels. To alleviate those degradations, we propose to adopt a transformatio

Co-existing disorders in ADHD - implications for diagnosis and intervention

Background It is only recently that comorbidity in ADHD has come to the forefront as one of the most important aspects of the disorder. It is agreed that, often, these problems are at least as important as ADHD in contributing to the longer term outcome in the individual child. Objective To provide the reader with basic information about clinics and treatment of comorbidity in ADHD. Method Revie

Oxygen loss and thermal double donor formation in germanium

Kinetics of interstitial oxygen loss and oxygen-related thermal double donor (TDD) generation upon heat treatments of Ge:O crystals at 350 degrees C have been studied. The TDD concentration (N-TDD) was derived from Hall effect measurements in the temperature range 77-400 K. The bistability of the first TDD species was taken into account. The interstitial oxygen concentration ([O-i]) in the crystal

Effect of clarithromycin on nuclear factor-kappa B and transforming growth factor-beta in chronic rhinosinusitis

OBJECTIVES: Long-term, low-dose macrolide therapy is effective in the treatment of chronic rhinosinusitis. It is believed that macrolide antibiotics produce this benefit through an anti-inflammatory effect. In this study, the effect of clarithromycin treatment on the expression of transforming growth factor (TGF)-beta and the key pro-inflammatory nuclear transcription factor, NF-kappa B, was exami

Nurses' personalities, nursing-related qualities and work satisfaction: a 10-year perspective

The personalities and qualities of nursing personnel are considered to be of great importance for their interactions and nursing relationships with patients and may also influence work satisfaction. The aim of the study was to explore the extent to which different personal qualities and personality factors, with a possible effect on motivation, professional conduct and coping with stress and anxie