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Mixed systems of hydrophobically modified polyelectrolytes: Controlling rheology by charge and hydrophobe stoichiometry and interaction strength

Rheology and phase separation were investigated for aqueous mixtures of two oppositely charged hydrophobically modified polyelectrolytes. The typical phase separation, normally seen for oppositely charged polymer mixtures, is dramatically reduced by the presence of hydrophobic modification, and phase separation is only detected close to the point of charge neutralization. While the two polyelectro

Wave characteristics distributions for Gaussian waves - wave-length, amplitude and steepness

In as tationary stochastic process the wave-length and amplitude are defined as the difference in time and height between a crest and the following trough. The distributions of these quantities are of great practical importance, but no closed form expressions are known at present. In previous papers we have presented an approximation which gives correct upper and lower bounds, regardless of the co

Five-Year Outcome of Cholinergic Treatment of Alzheimer's Disease: Early Response Predicts Prolonged Time until Nursing Home Placement, but Does Not Alter Life Expectancy.

Fifty consecutive outpatients with Alzheimer’s disease (AD) received treatment with the cholinesterase inhibitor tacrine in an open longitudinal study. Assessments using Mini-Mental State Examination, Alzheimer’s Disease Assessment Scale – cognitive subscale, and a global rating were made at baseline and at 6, 12, 24, 36, 48 and 60 months. Three outcome groups were characterized: responders, uncha

A longitudinal population study of climacteric symptoms and their treatment in a random sample of Swedish women

Objectives To assess, first, the prevalence and severity of symptoms associated with the climacteric period and their treatment and, second, the prevalence of exercise, smoking and body weight in a population-based sample of Swedish women. Material and methods Prospective, longitudinal cohort study, initiated in 1992, in women aged 46, 50, 54, 58 and 62 years with a follow-up 6 years later. Inform

Best leads in the standard electrocardiogram for the emergency detection of acute coronary syndrome.

Background and Purpose: The purpose of this study was to determine which leads in the standard 12-lead electrocardiogram (ECG) are the best for detecting acute coronary syndrome (ACS) among chest pain patients in the emergency department. Methods: Neural network classifiers were used to determine the predictive capability of individual leads and combinations of leads from 862 ECCs from chest pain

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The study extends a previous investigation on the use of oral decongestants during pregnancy with another 1 000 women (1 017 infants) who reported the use of such drugs in early pregnancy and 1 125 women (1 145 infants) who had such drugs prescribed later in pregnancy. The results on the beneficial delivery outcome after late use of the drugs with a reduced rate of preterm birth and low birth weig

The Grain family of stream ciphers

Abstract in UndeterminedA new family of stream ciphers, Grain, is proposed. Two variants, a 80-bit and a 128-bit variant are specified, denoted Grain and Grain-128 respectively. The designs target hardware environments where gate count, power consumption and memory are very limited. Both variants are based on two shift registers and a nonlinear output function. The ciphers also have the additional

Catching Up In Pharmaceuticals: Government Policies and the Rise of Genomics

Genomics — the sequencing of the human genome and the identification of the genetic mechanisms of development and disease — is driving a restructuring of the global pharmaceutical industry. Many policy initiatives in biomedicine are based on the assumption that strength in genomics research will be translated into economic success, that is, that investments in genomics will be a way to catch up in

Tau and Abeta42 in cerebrospinal fluid from healthy adults 21-93 years of age: establishment of reference values

BACKGROUND: Tau protein and the 42-amino acid form of beta-amyloid (Abeta42) measured in cerebrospinal fluid (CSF) have been proposed as potential biochemical diagnostic markers for Alzheimer disease. For the introduction of these assays in clinical practice, adequate reference values are of importance. METHODS: CSF samples were obtained from 231 neurologically and psychiatrically healthy individu

The application of green purchasing tools in the corporate sector

Abstract in UndeterminedAll types of organizations are under increasing pressure to integrate green considerations in their purchasing practices. A number of tools aimed for the practitioners have been developed in response to their new challenges. However, the application of such tools among private firms is not well known, and one important question is how well the tools correspond with practiti

Quantification of low-velocity motion using a navigator-echo supported MR velocity-mapping technique: application to intracranial dynamics in volunteers and patients with brain tumours

Gradient-echo pulse sequences with velocity-encoding gradients of 22.5-25 mT/m, were used for brain-motion and CSF-flow studies. To reduce motion artifacts, a phase-correction technique based on navigator echoes was evaluated. Three patients with right-sided parietal tumours were investigated; one astrocytoma grade III-IV, one astrocytoma grade I-II and one benign meningioma. In healthy volunteers

Phosphorylation of PDE3B by phosphatidylinositol 3-kinase associated with the insulin receptor

Phosphatidylinositol 3-kinase mediates several actions of insulin including its antilipolytic effect. This effect is elicited by the insulin-stimulated serine phosphorylation and activation of cGMP-inhibited phosphodiesterase (PDE3B). In human adipocytes, we found that insulin differentially stimulated phosphatidylinositol 3-kinase activity; the lipid kinase activity was associated with IRS-1, whe

Aromatic Allylation via Diazotization, Variation of the Allylic Moiety and a Short Route to a Benzazepine Derivative.

A continued study of the recently discovered diazotizative allylation (DiazAll) reaction of aniline derivatives is reported. Several allyl reagents, commonly used in radical allylation reactions, were evaluated, and some of these reagents resulted in allylation when used in the DiazAll reaction. The best result was obtained with allyl bromide. Substituted allylic bromides gave the corresponding al

Interannual and interspecific variation in intensity of the parasitic fly, Philornis downsi, in Darwin’s finches

An integrative approach to managing host–parasite interactions that threaten species communities will benefit from identifying variation in parasite impact across host species, and host–parasite responses to annual climatic variation. We examine interannual, inter- and intraspecific variation in Philornis downsi intensity – an introduced blood sucking fly that causes high fitness costs in Darwin’s

Below-ground responses of silver birch trees exposed to elevated CO2 and O-3 levels during three growing seasons

Field-growing silver birch (Betula pendula Roth) clones (clone 4 and 80) were exposed to elevated CO2 and O-3 in open-top chambers for three consecutive growing seasons (1999-2001). At the beginning of the OTC experiment, all trees were 7 years old. We studied the single and interaction effects of CO2 and O-3 on silver birch below-ground carbon pools (i.e. effects on fine roots and mycorrhizas, so

Characterization of pyrrhotite in Cu-Ni-ore bodies from mines in Botswana by Mossbauer spectroscopy, X-ray diffraction, and thermomagnetometry

Cu-Ni ore bodies from five Botswana mines were investigated, using a combination of X-ray diffraction, thermomagnetic measurements, Mossbauer spectroscopy, and Inductively Coupled Plasma-Atomic Absorption Electro-optic Spectroscopy (ICP-AES). The four dominant phases in the ores were found to be pyrrhotite, magnetite, pentlandite, and chalcopyrite. Mossbauer spectroscopy shows that pyrrhotite is t

High-relaxivity supramolecular aggregates containing peptides and Gd complexes as contrast agents in MRI

Mixed supramolecular aggregates, obtained by assembling together two amphiphilic monomers (C18H37)2NCO(CH2)2CO(AdOO)5-G-CCK8 (AdOO is 8-amino-3,6-dioxaoctanoic acid, CCK8 is C-terminal octapeptide of cholecystokinin) and (C18H37)2NCO(CH2)2COLys(DTPAGlu)CONH2 (DTPAGlu is N,N-bis[2-[bis(carboxyethyl)amino]ethyl]-l-glutamic acid), are characterized for their structural parameters by dynamic light sca

Fouling of electrodialysis membranes by organic substances

In this investigation, the influence of various kinds of organic solutes on the fouling of an anion and a cation selective ED membrane was studied. Fouling by adsorption of organic matter onto the membrane was measured as an increase in the membrane resistance with time. Experiments were performed with a fatty acid (octanoic acid), two anionic surfactants (sodium octanoate and sodium dodecylbenzen