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Harmonic morphisms from the classical non-compact semisimple Lie groups

We construct the first known complex-valued harmonic morphisms from the non-compact Lie groups View the MathML source, SU*(2n) and View the MathML source equipped with their standard Riemannian metrics. We then introduce the notion of a bi-eigenfamily and employ this to construct the first known solutions on the non-compact Riemannian SO*(2n), SO(p,q), SU(p,q) and Sp(p,q). Applying a duality princ

The effect of alpha-synuclein knockdown on MPP plus toxicity in models of human neurons

The protein alpha-synuclein is central to the pathophysiology of Parkinson's disease (PD) but its role in the development of neurodegeneration remains unclear. alpha-Synuclein-knockout mice develop without gross abnormality and are resistant to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a mitochondrial inhibitor widely used to model parkinsonism. Here we show that differentiated human do

The role of inter-specific, micro-habitat and climatic factors on the carbon isotope (delta C-13) variability of a modern leaf assemblage from northern Scandinavia: implications for climate reconstruction

To provide a basis for the interpretation of past climatic conditions from Quaternary leaf records, leaf carbon isotope (delta C-13) results are presented for 12 northern European dwarf-shrub, shrub and tree species growing across a network of 18 sites in northern Scandinavia. The role of micro-habitat (hummock/hollow) on carbon isotope trends is explored in addition to a comparison of the carbon

Direct action on the molecule is one of several mechanisms by which ultrasound enhances the fibrinolytic effects of reteplase.

Enhanced fibrinolytic reperfusion therapy may improve the outcome in embolic stroke, where ultrasound exposure has been shown to be one option. We recently verified that the fibrinolytic properties of streptokinase were modulated following ultrasound exposure of the molecule. We have now explored this possibility following ultrasound exposure of the reteplase molecule. The effects on clot lysis of

Accumulation of ubiquitin conjugates in a polyglutamine disease model occurs without global ubiquitin/proteasome system impairment

Aggregation-prone proteins have been suggested to overwhelm and impair the ubiquitin/proteasome system (UPS) in polyglutamine (polyQ) disorders, such as Huntington's disease (HD). Overexpression of an N-terminal fragment of mutant huntingtin (N-mutHtt), an aggregation-prone polyQ protein responsible for HD, obstructs the UPS in cellular models. Furthermore, based on the accumulation of polyubiquit

Macroporous monolithic hydrogels in a 96-minicolumn plate format for cell surface-analysis and integrated binding/quantification of cells

Macroporous monolithic hydrogels (cryogel monoliths; rods 12.5 mm x 7.1 mm diameter) are elastic, sponge-like materials with large (10-100 mu m), interconnected pores. Phenyl- and IMAC-(Me(II)-iminodiacetic acid)-cryogel monoliths were inserted into the open-ended wells of a standard 96-well plate, forming a system of 96 drainage-protected minicolumns, and were used in a parallel assay of hydropho

Phase transition in vertex-reinforced random walks on Z with non-linear reinforcement

Vertex-reinforced random walk is a random process which visits a site with probability proportional to the weight w k of the number k of previous visits. We show that if w k ∼ k α, then there is a large time T 0 such that after T 0 the walk visits 2, 5, or ∞ sites when α < 1, = 1, or > 1, respectively. More general results are also proven.

Assessment of QT-measurement accuracy using the 12-lead electrocardiogram derived from EASI leads

The purpose of the present study is to assess QT-interval measurements from the EASI 12-lead electrocardiogram (ECG) as compared with the standard 12-lead ECG. The QT interval was automatically determined in simultaneously recorded standard and EASI 12-lead ECGs, using a validated wavelet-based delineator. The agreement between the 2 sets of measurements was quantified both on a lead-by-lead basis

Eating difficulties, complications and nursing interventions during a period of three months after a stroke

AIM: The aim of this study was to describe eating difficulties and especially swallowing in patients with dysphagia, types of nursing intervention, and the development of complications over 3 months. The aim was also to explore common characteristics of eating difficulties that influenced the ability to finish meals. METHODS: Twenty-four consecutive patients admitted because of stroke and dysphagi

Higher cumulative revision rate of knee arthroplasties in younger patients with osteoarthritis

This study was designed to test the hypothesis that younger patients treated for osteoarthritis and similar conditions using total knee arthroplasty and unicompartmental knee arthroplasty have a lower implant survival rate when compared with older patients. Previous studies have been done on a small number of patients and only included the younger patients. In many cases patients treated for rheum

Soot volume fraction measurements in aero-engine exhausts using extinction-calibrated backward laser-induced incandescence

Control and reduction of soot particle emissions from aeronautic turbines requires a monitoring system suitable for quantification of these emissions. Currently, such emissions are estimated using the technique of smoke number. This is an extractive method, which is not sensitive enough for the low emission levels of modern gas turbines. Within a recent European project, AEROTEST, part of the proj

A dual to Lyapunov's stability theorem

Lyapunov's second theorem is a standard tool for stability analysis of ordinary differential equations. Here we introduce a theorem which can be viewed as a dual to Lyapunov's result. From existence of a scalar function satisfying certain inequalities it follows that “almost all trajectories” of the system tend to zero. The scalar function has a physical interpretation as the stationary density of

Parallel fiber receptive fields: a key to understanding cerebellar operation and learning.

In several theories of the function of the cerebellum in motor control, the mossy-fiber-parallel fiber input has been suggested to provide information used in the control of ongoing movements whereas the role of climbing fibers is to induce plastic changes of parallel fiber (PF) synapses on Purkinje cells. From studies of climbing fibers during the last few decades, we have gained detailed knowled

Steam condensation in parallel channels of plate heat exchangers- an experimental investigation

An experimental investigation has been carried out to find the pressure difference of the process of steam condensation across the port to channel in plate heat exchangers. In the present study, low corrugation angle (30°) plates have been used for different number of channels, namely, 10 and 80. The process steam entered at 1 bar with a small degree of superheat. Water has been used as the cold f

Endometrial expression of vasopressin, oxytocin and their receptors in patients with primary dysmenorrhoea and healthy volunteers at ovulation.

OBJECTIVE: To investigate gene expressions for neurohypophyseal and ovarian hormones as well as their receptors in the endometrium of women with primary dysmenorrhoea and healthy subjects at ovulation. STUDY DESIGN: A group of eight women with moderate to severe dysmenorrhoea and eight healthy subjects were compared in parallel between 18 and 35 years of age, regularly menstruating, non-overweight

High-resolution Late Silurian correlations between Gotland, Sweden and the Broken River region, NE Australia: Lithologies, conodonts and isotopes

High-resolution correlations, partly with a precision better than 10 ka, are achieved between late Ludfordian sequences on Gotland, Sweden (on Baltica), and a section (COG) through the Coral Gardens Formation along the Broken River, northeastern Australia (on Gondwana), despite these sections having been on different palaeocontinents facing different oceans. The interval is characterised by rapid,

Crystal structure of human cystatin D, a cysteine peptidase inhibitor with restricted inhibition profile.

Cystatins are natural inhibitors of papain-like (family C1) and legumain-related (family C13) cysteine peptidases. Cystatin D is a type 2 cystatin, a secreted inhibitor found in human saliva and tear fluid. Compared to its homologues, cystatin D presents an unusual inhibition profile with a preferential inhibition cathepsin S > cathepsin H > cathepsin L, and no inhibition of cathepsin B or pig leg

Fixation of distal radius fractures using a fragment-specific system

Operative treatment for distal radius fractures continues to evolve, but small-fragment fixation has some advantages compared with previous methods. We assessed two groups of patients. Group 1 was an initial series of patients treated with small-fragment fixation at a large institution in the United States, and Group 2 was a review of patients treated in Lund, Sweden. The first group was evaluated

Structure of Proton-Conducting Alkali Thio-Hydroxogermanates

Using it combination Of neutron diffraction, infrared spectroscopy. and first-principles calculations, we have investigated the structure of hydrated and dehydrated proton conducting alkali thio-hydroxogermanates of general formula M2GeS2(OH)(2)center dot yH(2)O (M = K, Rb, and Cs). The results show that the structure of hydrated and dry materials are basically the same, which confirms previous in