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Exponential splitting for unbounded operators

We present a convergence analysis for exponential splitting methods applied to linear evolution equations. Our main result states that the classical order of the splitting method is retained in a setting of unbounded operators, without requiring any additional order condition. This is achieved by basing the analysis on the abstract framework of (semi)groups. The convergence analysis also includes

Neurogenin2 identifies a transplantable dopamine neuron precursor in the developing ventral mesencephalon.

In neural transplantation studies, there is an interest in identifying and isolating mesencephalic dopamine (mesDA) neuron precursors that have the capacity to differentiate into fully mature mesDA neurons after transplantation. We report here that in the developing ventral mesencephalon (VM) the proneural gene Neurogenin2 (Ngn2) is expressed exclusively in the part of the ventricular zone that gi

Sentinel lymph node biopsy in operations for recurrent breast cancer

Background: In a pilot prospective consecutive series on 50 patients with recurrent breast cancer, results of sentinel lymph node biopsy (SLNB) are reported. The interval between primary operation and recurrence was 8 years (range 1-18 years). Only three patients had not undergone dissection of the axilla (ALND). Results: In 51% of patients scintigraphy disclosed sentinel nodes (SN). At operation

pi K scattering in three flavour ChPT : π K scattering in three flavour ChPT

We present the scattering lengths for the piK processes in the three flavour Chiral Perturbation Theory (ChPT) framework at next-to-next-to-leading order (NNLO). The calculation has been performed analytically but we only include analytical results for the dependence on the low-energy constants (LECs) at NNLO due to the size of the expressions. These results, together with resonance estimates of t

Consensus meeting on microdialysis in neurointensive care

Background: Microdialysis is used in many European neurointensive care units to monitor brain chemistry in patients suffering subarachnoid hemorrhage (SAH) or traumatic brain injury (TBI). Discussion: We present a consensus agreement achieved at a meeting in Stockholm by a group of experienced users of microdialysis in neurointensive care, defining the use of microdialysis, placement of catheters,

Lack of replication of association findings in complex disease: an analysis of 15 polymorphisms in prior candidate genes for sporadic Alzheimer's disease

There is considerable enthusiasm for the prospect of using common polymorphisms (primarily single nucleotide polymorphisms; SNPs) in candidate genes to unravel the genetics of complex disease. This approach has generated a number of findings of loci which are significantly associated with sporadic Alzheimer's disease (AD). In the present study, a total of 15 genes of interest were chosen from amon

Oxidized alpha(1)-antitrypsin stimulates the release of monocyte chemotactic protein-1 from lung epithelial cells: potential role in emphysema

Li Z, Alam S, Wang J, Sandstrom CS, Janciauskiene S, Mahadeva R. Oxidized alpha(1)-antitrypsin stimulates the release of monocyte chemotactic protein-1 from lung epithelial cells: potential role in emphysema. Am J Physiol Lung Cell Mol Physiol 297: L388-L400, 2009. First published June 12, 2009; doi:10.1152/ajplung.90373.2008.-alpha(1)-Antitrypsin ( AT) is a major elastase inhibitor within the lun

Optimization of steam pretreatment of corn stover to enhance enzymatic digestibility

Among the available agricultural byproducts, corn stover, with its yearly production of 10 million t (dry basis), is the most abundant promising raw material for fuel ethanol production in Hungary. In the United States, more than 216 million t of corn stover is produced annually, of which a portion also could possibly be collected for conversion to ethanol. However, a network of lignin and hemicel

Disturbance from roads negatively affects Andean condor habitat use

Human disturbance can be a severe problem for some animal species. Behavioural ecology theory predicts that sensitivity to mortality risks, and thereby to disturbance, will be related to life-history characteristics. Long-lived species with low reproductive rates are expected to have a high cost of predation and therefore avoid risks strongly. In this paper we quantify the effect of roads on the A

The effect of organic farming on butterfly diversity depends on landscape context

The recent dramatic decline in farmland biodiversity is often attributed to agricultural intensification and structural changes in the agricultural landscape. One suggested farm practice seen to benefit biodiversity and reverse declines is organic farming. Because organic farming is viewed as a more sustainable form of agriculture it is currently subsidized by European agri-environment schemes. Ho

Small animal imaging with pinhole single-photon emission computed tomography

BACKGROUND. High resolution spatial details of the distribution of activity in three dimensions is required to evaluate the localization and dosimetric properties of radiolabelled monoclonal antibodies in tumors and normal tissues. Planar imaging of small animals with a resolution of 5-10 mm is usually the imaging modality of choice. The authors investigated high resolution single-photon emission

Photoexcitation of excitons in self-assembled quantum dots

Using an approach of combining Fourier transform infrared spectroscopy with resonant illumination from a secondary external light source, we have measured the photocurrent (PC) for multiple layers of self-assembled InAs dots embedded in a matrix of InP. Without external illumination, we observe photoexcitation of electrons from bound states in the dots to the InP barrier. By additional illuminatio

Beta1 integrin is not essential for hematopoiesis but is necessary for the T cell-dependent IgM antibody response.

Several experimental evidences suggested that beta1 integrin-mediated adhesion of hematopoietic stem cells (HSC) is important for their function in the bone marrow (BM). Using induced deletion of the beta1 integrin gene restricted to the hematopoietic system, we show that beta1 integrin is not essential for HSC retention in the BM, hematopoiesis, and trafficking of lymphocytes. However, immunizati

A broadband laser plasma X-ray source for application in ultrafast chemical structure dynamics

A plasma source free from characteristic emission lines is described, based on laser irradiation of a water jet in a helium atmosphere. Various key aspects of the laser interaction are presented along with practical characterization of the observed isotropic ~4–10 keV x-ray emissions, measurements of which indicate subpicosecond duration. Observations are consistent with a vacuum heating plasma me