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Optimal cepstrum estimation using multiple windows

The aim of this paper is to find a multiple window estimator that is mean square error optimal for cepstrum estimation. The estimator is compared with some known multiple window methods as well as with the parametric AR-estimator. The results show that the new estimator has high performance, especially for data with large spectral dynamics, and that it is also robust against parameter choices. Sim

Dissemination of Thrombolysis for Acute Ischemic Stroke Across a Nation. Experiences From the Swedish Stroke Register, 2003 to 2008.

BACKGROUND AND PURPOSE: We used Riks-Stroke, the Swedish Stroke Register, to explore how thrombolysis has been disseminated in Swedish hospitals since it was approved in 2003. METHODS: All 78 hospitals in Sweden admitting patients with acute stroke participate in Riks-Stroke. Between 2003 and 2008, 72 033 adult patients were hospitalized for acute ischemic stroke. We analyzed thrombolysis use by r

The Ca2+-Regulation of the Mitochondrial External NADPH Dehydrogenase in Plants Is Controlled by Cytosolic pH.

NADPH is a key reductant carrier that maintains internal redox and antioxidant status, and that links biosynthetic, catabolic and signalling pathways. Plants have a mitochondrial external NADPH oxidation pathway, which depends on Ca2+ and pH in vitro, but concentrations of Ca2+ needed are not known. We have determined the K0.5(Ca2+) of the external NADPH dehydrogenase from Solanum tuberosum mitoch

Archaeal Ammonia Oxidizers Dominate in Numbers, but Bacteria Drive Gross Nitrification in N-amended Grassland Soil.

Both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) play an important role in nitrification in terrestrial environments. Most often AOA outnumber AOB, but the relative contribution of AOA and AOB to nitrification rates remains unclear. The aim of this experiment was to test the hypotheses that high nitrogen availability would favor AOB and result in high gross nitrification r

Polyphase structural evolution of a fine-grained, fold-dominated end moraine, Bruarjokull surge-type glacier, Iceland

The glaciotectonic architecture and structural evolution of a fine-grained end moraine formed by the 1890 glacier surge of Bruarjokull is described from four excavated cross-sections. The end moraine ridge is a morphological expression of a marginal sedimentary wedge formed during the last days of the surge. The actual end-moraine ridge was formed on the last day of the 1890 surge when the glacier

Rödlistade och sällsynta vedskalbaggar i Strömsrum, Småland. [Red-listed and rare wood-living beetles at Strömsrum, Småland]

Strömsrum in SE Sweden is one of the most important areas for threatened insects in northern Europe. This is a review of the red-listed and formerly red-listed species of wood-living beetles collected at Strömsrum with notes of their habitats. In an area of a few hundred hectares over 1000 old hollow oaks and almost as many hollow trees of other deciduous trees occur. From the current red list (Gä

Strong microsite control of seedling recruitment in tundra

The inclusion of environmental variation in studies of recruitment is a prerequisite for realistic predictions of the responses of vegetation to a changing environment. We investigated how seedling recruitment is affected by seed availability and microsite quality along a steep environmental gradient in dry tundra. A survey of natural seed rain and seedling density in vegetation was combined with

Quantitative 3D imaging of scattering media using structured illumination and computed tomography

An imaging technique capable of measuring the extinction coefficient in 3D is presented and demonstrated on various scattering media. The approach is able to suppress unwanted effects due to both multiple scattering and light extinction, which, in turbid situations, seriously hampers the performance of conventional imaging techniques. The main concept consists in illuminating the sample of interes

α-decay spectra of odd nuclei using the effective Skyrme interaction

Background: For nuclei heavier than Pb-208 alpha decay is a dominating decay mode. alpha decay of odd nuclei can give spectroscopic information because different states in the daughter nucleus can be populated in the decay. Purpose: To explore and test microscopic descriptions of alpha decay of odd nuclei based on self-consistent models with effective nuclear interactions. To predict the hindrance

Photocoagulation of human retinal pigment epithelial cells in vitro: evaluation of necrosis, apoptosis, cell migration, cell proliferation and expression of tissue repairing and cytoprotective genes.

Sight-threatening diabetic retinopathy has been treated with photocoagulation for decades but the mechanisms behind the beneficial clinical effects are poorly understood. One target of irradiation and a potential player in this process is the retinal pigment epithelium (RPE). Here we establish an in vitro model for photocoagulation of human RPE cells.

A Singular Value Decomposition Based Closed Loop Stability Preserving Controller Reduction Method

In this paper a controller reduction method which preserves closed loop stability is described. A Lyapunov inequality based sufficient condition is proposed in the search of the reduced controller. The reduced controller leads to a stable closed loop system with guaranteed approximation quality. Furthermore, the proposed problem can be formulated as a matrix approximation problem which can be solv

Testing a post-copulatory pre-zygotic reproductive barrier in a passerine species pair

Sexual selection may drive speciation, but most research focuses on pre-copulatory sexual selection, overlooking post-copulatory processes. Post-copulatory sexual selection in allopatric populations could drive divergence in post-copulatory pre-zygotic (PCPZ) phenotypes, limiting gene flow upon secondary contact. Here, we performed in vitro experiments examining one potential PCPZ barrier between

Endovascular Repair of Acute Uncomplicated Aortic Type B Dissection Promotes Aortic Remodelling: 1 Year Results of the ADSORB Trial

Objectives: Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint

Functionality of epidermal melanin pigments: current knowledge on UV-dissipative mechanisms and research perspectives.

So far it is not known whether epidermal melanins are solely photoprotective or also phototoxic. Also largely unknown are underlying UV-induced mechanisms and impact of the chemical structure. This perspective will focus on the current insights into the UV-dissipative mechanisms in melanin model systems and the implications for the in vivo pigments. We will also identify future research perspectiv

Pituitary Homeobox 2 Regulates Adrenal4 Binding Protein/Steroidogenic Factor-1 Gene Transcription in the Pituitary Gonadotrope through Interaction with the Intronic Enhancer

Ad4BP/SF-1 (Adrenal4 Binding Protein/Steroidogenic Factor-1 (NR5A1)) is a factor important for animal reproduction and endocrine regulation, and its expression is tightly regulated in the gonad, adrenal gland, ventromedial hypothalamic nucleus (VMH), and pituitary gonadotrope. Despite its functional significance in the pituitary, the mechanisms underlying pituitary-specific expression of the gene

In vivo production of catalase containing haem analogues.

Haem (protohaem IX) analogues are toxic compounds and have been considered for use as antibacterial agents, but the primary mechanism behind their toxicity has not been demonstrated. Using the haem protein catalase in the Gram-positive bacterium Enterococcus faecalis as an experimental system, we show that a variety of haem analogues can be taken up by bacterial cells and incorporated into haem-de

Modification of SOVA-based Algorithms for Efficient Hardware Implementation

In this paper, a modified soft-output Viterbi algorithm (SOVA) is presented to enable efficient hardware implementation. The forward-only processing of the SOVA has an inherent lower latency than forward-backward algorithms such as BCJR and its offspring, which are commonly used in iterative decoders. Thus, SOVA-based architectures require less parallelization and therefore hardware for the same d