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Quartz content and the quartz-to-plagioclase ratio determined by X-ray diffraction: a proxy for ice rafting in the northern North Atlantic?

Many paleoceanographic reconstructions of the glacial North Atlantic include estimates of iceberg discharge, which are based on the variable abundance of ice-rafted detritus (IRD) in deep-sea sediments. IRD abundance is most often determined by the mechanical separation and painstaking counting of terrigenous particles larger than a specified threshold grain size, typically 150 mum. Here we presen

Laterally and mutually constrained inversion of surface wave seismic data and resistivity data

The laterally and mutually constrained inversion (LCI and MCI) techniques allow for the combined inversion of multiple geophysical datasets and provide a sensitivity analysis of all model parameters. The LCI and MCI work with few-layered models, and are restricted to quasi-layered geological environments. LCI is used successfully for inversion of surface wave (SW) seismic data and MCI for combined

Expecting the unforeseeable: The 2007 Turkish elections in the media

This study presents an analysis of how the media reported the 2007 elections in Turkey. Past research on election campaign media coverage, particularly newspapers, suggests that the media can play an important role in informing voters. However, much of the research on campaign media coverage has focused on Western democracies with little attention paid to how features of the media system such as p

The importance of sexual and asexual reproduction in the recent evolution of Allium vineale

In the weedy plant species Allium vineale (wild garlic), individuals may simultaneously produce sexually and asexually derived offspring, by seed and bulbils, respectively. In this study, genetic and genotypic diversity was determined in samples from 14 European A. vineale populations using nuclear (RAPD) and cytoplasmic (PCR-RFLP of cpDNA) markers to investigate the importance of the different re

Comparison of low dose nicotinamide versus benzamide, administered per os, as radiosensitizers in a C3H mammary carcinoma

We have evaluated if any differences in tumor radiosensitization exist between the two adenosine diphosphate ribosyl transferase (ADPRT) inhibitors nicotinamide and benzamide at fractionated low doses. A significant radiosensitizing effect with nicotinamide at a 10 mg/kg per day dose was found in the tumor model used. We found, however, no radiosensitizing effect with benzamide given according to

Efficacy of desmopressin in the treatment of nocturia: a double-blind placebo-controlled study in men.

OBJECTIVE: To investigate the efficacy and safety of oral desmopressin in the treatment of nocturia in men. PATIENTS AND METHODS: Men aged >/=18 years with verified nocturia (>or=two voids/night) and nocturnal urine production greater than their maximum functional bladder capacity were recruited. A 3-week dose-titration phase established the optimum desmopressin dose (0.1, 0.2 or 0.4 mg). After a

Neonatal ACE inhibition in rats interferes with lung development.

The renin-angiotensin system (RAS) is developmentally up-regulated and it is essential for kidney development in several species. Given the fact that the rat lung undergoes postnatal development, the mammalian lung possesses the highest angiotensin-converting enzyme (ACE) levels and ACE activity increases during the first weeks postpartum, we tested the hypothesis that ACE inhibition influences po

Ultrastructural cerebrovascular changes in a model of subarachnoid hemorrhage in baboon based on triple cisternal blood injection

In a subarachnoid hemorrhage model in the baboon, achieved through three cisternal blood injections with 1-day intervals, the cerebral arteries were dissected out 7 days after the first blood injection for electron microscopy All the animals showed ultrastructural changes in the cerebral arteries: two with severe, one with moderate, and three with mild alterations in the vessel walls. The most con

Cutting Tool Fracture Prediction and Strength Evaluation by Stress Identification Part I: Stress Model

Cutting tool premature failure, caused by tool fracture and chipping, is a frequent problem in the metal cutting area. For a certain type of cutting tool, correctly identifying its load profile and property profile is very crucial for prediction of the tool premature failure. The most direct way to evaluate the load profile and property profile of a cutting tool is to identify the stress working o

Red giant stellar collisions in the Galactic Centre

We show that collisions with stellar-mass black holes can partially explain the absence of bright giant stars in the Galactic Centre, first noted by Genzel et al. We show that the missing objects are low-mass giants and asymptotic giant branch stars in the range 1-3 M-circle dot. Using detailed stellar evolution calculations, we find that to prevent these objects from evolving to become visible in

Exact density functional theory for ideal polymer fluids with nearest neighbor bonding constraints

We present a new density functional theory of ideal polymer fluids, assuming nearest-neighbor bonding constraints. The free energy functional is expressed in terms of end site densities of chain segments and thus has a simpler mathematical structure than previously used expressions using multipoint distributions. This work is based on a formalism proposed by Tripathi and Chapman [Phys. Rev. Lett.

Bisexuals in relationships: uncoupling intimacy from ontology

A dominant notion that homosexuality and heterosexuality give meaning to bisexuality already exists. But no one has explored the meaning that bisexuality might accrue with regard to monosexuality. Because bisexuals were never fully recognized within queer theory, the homosexual-heterosexual binary opposition continues to be the primary understanding of difference. Further, within queer theory, the

Real-time control of a virtual hand

A myoelectric control system for prostheses was developed and evaluated on six healthy subjects. These were able to control a computer-animated hand in real-time with a 20 Hz update rate. A data glove, equipped with joint angle sensors, was used to train the system and to evaluate the continuous predictions of joint angles. A linear envelop filter was used for EMG signal pre-processing and the rec

Molecular population divergence and sexual selection on morphology in the banded demoiselle (Calopteryx splendens)

The importance of sexual selection in population divergence is of much interest, mainly because it is thought to cause reproductive isolation and hence could lead to speciation. Sexually selected traits have been hypothesized to diverge faster between populations than other traits, presumably because of differences in the strength, mechanism or dynamics of selection. We investigated this by quanti

InAs nanowire metal-oxide-semiconductor capacitors

We present a capacitance-voltage study for arrays of vertical InAs nanowires. Metal-oxide-semiconductor (MOS) capacitors are obtained by insulating the nanowires with a conformal 10 nm HfO2 layer and using a top Cr/Au metallization as one of the capacitor's electrodes. The described fabrication and characterization technique enables a systematic investigation of the carrier density in the nanowire

Variability in the G3 domain content of bovine aggrecan from cartilage extracts and chondrocyte cultures

The content of the globular domains G1, G2 and G3 on the core protein of high-density (A1D1) aggrecan isolated from newborn and mature bovine cartilage and from cultures of bovine chondrocytes was examined. Quantitation based on the 220 nm absorbance of tryptic marker peptides from each domain isolated by reversed-phase HPLC showed that while the content of G1 and G2 was essentially the same for a

Simulations of the glaciation of a frontal mixed-phase cloud with the Explicit Microphysics Model

Simulations with the Explicit Microphysics Model (EMM) of a case of lightly precipitating, glaciated stratiform cloud are presented. This frontal cloud was observed by the UK Met Office C-130 aircraft and the dual-polarization radar at Chilbolton in southern England. The Hallett-Mossop (H-M) process was found to cause extremely high number concentrations of crystal columns of up to almost 1000 1(-