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Land use studies in drylands: an evaluation of object-oriented classification of very high resolution panchromatic imagery

Object-oriented classification approaches offer an alternative to per-pixel methods for assessment of land use and land cover. Combining object-oriented approaches with very high resolution imagery may provide enhanced possibilities for applications requiring land use and land cover data. The aim of this study is to evaluate the application of object-oriented classification of panchromatic very hi

MYC-containing double minutes in hematologic malignancies: evidence in favor of the episome model and exclusion of MYC as the target gene

Double minutes (dmin)-circular, extra-chromosomal amplifications of specific acentric DNA fragments-are relatively frequent in malignant disorders, particularly in solid tumors. In acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS), dmin are observed in similar to 1% of the cases. Most of them consist of an amplified segment from chromosome band 8q24, always including the MYC gene. B

Analysis of sampling errors in biopsy techniques using data from whole muscle cross sections

Because of the large variability in the proportion of fiber types within a whole muscle, a single biopsy is a poor estimator of the fiber type proportion for a whole muscle. Data on the proportions of type I and II fibers, obtained from cross sections of whole human muscles (vastus lateralis) from young male individuals, have therefore been analyzed statistically in order to determine the sampling

t(19;22)(q13;q12) Translocation Leading to the Novel Fusion Gene EWSRI-ZNF444 in Soft Tissue Myoepithelial Carcinoma

Myoepithelial neoplasms of soft tissue have only recently been acknowledged as a separate diagnostic entity. To know based on histological appearance whether these tumors are benign or malignant is often difficult, and their tumorigenic mechanisms remain poorly understood. We report a myoepithelial carcinoma with an aberrant near-diploid karyotype, 43 similar to 47,XX,add(1)(p34)x2,add(3)(q27)x2,d

A simple test for cointegration in dependent panels with structural breaks

This paper develops a very simple test for the null hypothesis of no cointegration in panel data. The test is general enough to allow for heteroskedastic and serially correlated errors, unit-specific time trends, cross-sectional dependence and unknown structural breaks in both the intercept and slope of the cointegrated regression, which may be located at different dates for different units. The l

Multiple displacement amplification of DNA from human colon and rectum biopsies: Bacterial profiling and identification of Helicobacter pylori-DNA by means of 16S rDNA-based TTGE and pyrosequencing analysis

Amplifying bacterial DNA by PCR from human biopsy specimens has sometimes proved to be difficult, mainly due to the low amount of bacterial DNA present. Therefore, nested or semi-nested 16S rDNA PCR amplification has been the method of choice. In this study, we evaluate the potential use of whole genome amplification of total DNA isolated from human colon and rectum biopsy specimens, followed by 1

Two-dimensional gas-phase temperature measurements using phosphor thermometry

A new technique based on phosphor thermometry for measurements of two-dimensional gas-phase temperature, was examined as a new laser diagnostic. Calibration of Dy:YAG phosphor was carried out on the surface of a solid. The data were applicable for gas thermometry since the validation of the line intensity ratios method, showed good agreement with both the lifetime method and thermocouple data in a

Platelets support pulmonary recruitment of neutrophils in abdominal sepsis

Objective. Recent findings Indicate that platelets not only regulate thrombosis and hemostasis but may also be involved in proinflammatory activities. Herein, we hypothesized that platelets may play a role in sepsis by activating and priming circulating neutrophils for subsequent recruitment Into the lung. Design: Prospective experimental study. Setting. University Hospital Research Unit. Subject.

A theory of stochastic harvesting in stochastic environments

We investigate how model populations respond to stochastic harvesting in a stochastic environment. In particular, we show that the effects of variable harvesting on the variance in population density and yield depend critically on the autocorrelation of environmental noise and on whether the endogenous dynamics of the population display over- or undercompensation to density. These factors interact

Joint High-Resolution Fundamental Frequency and Order Estimation

In this paper, we present a novel method for joint estimation of the fundamental frequency and order of a set of harmonically related sinusoids based on the MUltiple SIgnal Classification (MUSIC) estimation criterion. The presented method, termed HMUSIC, is shown to have an efficient implementation using fast Fourier transforms (FFTs). Furthermore, refined estimates can be obtained using a gradien

Parietal lobe: Activation in rapid, automatized naming by adults

Three automatic naming tasks (Wiig & Nielsen, 1999) were administered to 60 normal functioning adults. The mean time required for naming 40 single-dimension (colors, forms, numbers, and letters) and 40 dual dimension stimuli (color-form, color-number, and color letter combinations) were compared in young (17-38 yr.) and older (40-68 yr.) men and women. Analysis of variance for the combined gro

Disentangling the effects of climate and people on Sahel vegetation dynamics

The Sahel belt of Africa has been the focus of intensive scientific research since the 1960s, spurred on by the chronic vulnerability of its population to recurring drought and the threat of long-term land degradation. But satellite sensors have recently shown that much of the region has experienced significant increases in photosynthetic activity since the early 1980s, thus re-energizing long-sta

A revised geochronology for the Blekinge Province, southern Sweden

Zircon grains from nine samples of metavolcanic rocks, gneisses, granitoids and migmatites from the Blekinge Province in southeasternmost Sweden have been dated by U-Pb using ion microprobe. The results suggest that most of the Blekinge bedrock was formed within a narrow time interval of 1.77-1.75 Ga, including the Vastana supracrustal formation and 'coastal gneisses' previously dated to c. 1.70 G

Endothelium-specific ablation of PDGFB leads to pericyte loss and glomerular, cardiac and placental abnormalities

Platelet-derived growth factor-B (PDGFB) is necessary for normal cardiovascular development, but the relative importance of different cellular sources of PDGFB has not been established. Using Cre-lox techniques, we show here that genetic ablation of Pdgfb in endothelial cells leads to impaired recruitment of pericytes to blood vessels. The endothelium-restricted Pdgfb knockout mutants also develop

Antagonism of rat beta -cell voltage-dependent K+ currents by exendin-4 requires dual activation of the cAMP/PKA and PI3 kinase signalling pathways.

Antagonism of voltage-dependent K+ (Kv) currents in pancreatic {beta}-cells may contribute to the ability of glucagon-like peptide-1 (GLP-1) to stimulate insulin secretion. The mechanism and signaling pathway regulating these currents in rat {beta}-cells were investigated using the GLP-1 receptor agonist exendin 4. Inhibition of Kv currents resulted from a 20-mV leftward shift in the voltage depen

The use of language in understanding subject matter

Abstract in UndeterminedEmpirical results show that frequently the meaning of expressions used by students in expressing their understanding of subject matter does not correspond to the meaning of those expressions in the subject matter theory that the students are expected to learn. There is also often a lack of identity of meaning between the same students' use of the same expression from one us

Bias and temperature dependence of the escape processes in quantum dots-in-a-well infrared photodetectors

The performance of quantum dots-in-a-well infrared photodetectors (DWELL IPs) has been studied by means of interband and intersubband photocurrent measurements as well as dark current measurements. Using interband photocurrent measurements, substantial escape of electrons from lower lying states in the DWELL structure at large biases was revealed. Furthermore, a significant variation in the escape

Molecular imaging with endogenous substances

Dynamic nuclear polarization has enabled hyperpolarization of nuclei such as C-13 and N-15 in endogenous substances. The resulting high nuclear polarization makes it possible to perform subsecond C-13 MRI. By using the dynamic nuclear polarization hyperpolarization technique, 10% polarization was obtained in an aqueous solution of 100 mM C-13-labeled urea, ready for injection. The in vivo T, relax