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Proton-conducting aromatic polymers carrying hypersulfonated side chains for fuel cell applications

Polysulfone main chains have been functionalized with hypersulfonated aromatic side chains where the sulfonic acid groups were highly concentrated on a local scale, with two acid groups placed on the same aromatic ring. This molecular design was implemented to promote the nanophase separation that takes place in proton-exchange membranes between the hydrophobic polymer main chain and the hydrophil

Structure and Dynamics for LiBH4-LiCl Solid Solutions

A Surprisingly high degree of structural and compositional dynamics is observed in the system LiBH4-LiCl as a function of temperature and time. Rietveld refinement of synchrotron radiation powder X-ray diffraction (SR-PXD) data reveals that Cl- readily substitutes for BH4- in the Structure of LiBH4. Prolonged heating a sample of LiBH4-LiCl (1:1 molar ratio) above the phase transition temperature a

Lipid management in cardiovascular disease prevention guidelines: Strategies and tactics for implementation.

Despite the widespread dissemination of clinical practice guidelines on the prevention and treatment of cardiovascular disease (CVD), CVD causes one third of deaths worldwide and almost half of all deaths in the developed world. It is therefore likely that, although some aspects of CVD management have improved, there is still a significant shortfall between what is known about CVD prevention and w

Towards a 'nano-traffic' system powered by molecular motors

In this work, we reconstructed in vitro the behavior of two motor proteins-myosin and actin-responsible for the mechanical action of muscle cells. By transferring this in vivo system to an artificial environment, we were able to study the interaction between the proteins in more detail, as well as investigating the central mechanism of force production. Nm-patterning by e-beam lithography (EBL) co

Variability in muscle fibre areas in whole human quadriceps muscle: how to reduce sampling errors in biopsy techniques

A single biopsy is a poor estimator of the muscle fibre cross-sectional area (CSA) for a whole human muscle because of the large variability in the fibre area within a muscle. To determine how the sampling errors in biopsy techniques can be reduced, data on the CSA of type 1 and type 2 fibres obtained from cross-sections of whole vastus lateralis muscle of young men, have been analysed statistical

High-speed biomarker identification utilizing porous silicon nanovial arrays and MALDI-TOF mass spectrometry

Speed and accuracy are crucial prerequisites in the application of proteomic methods to clinical medicine. We describe a microfluidic-based nanovial array for rapid proteolytic processing linked to MALDI-TOF MS. This microscale format consumes only minute amounts of sample, and it is compatible with rapid bioanalytical protocols and high-sensitivity readouts. Arrays of vials (300 mu m in diameter

Many-body polarization, a cause of asymmetric solvation of ions and quadrupoles

Three models are used to study the effect of many-body polarization in the solvation of non-dipolar molecules and ions in water. Two of the models are very simplified and are used to show a number of basic principles of correlation of solvent degrees of freedom and asymmetric solvent structures. These principles are used to interpret results from the third model: an accurate simulation of para-ben

Electronic speckle pattern interferometry: A novel non-invasive tool for studying drug transport rate through free films

In this work, Electronic Speckle Pattern Interferometry (ESPI) is presented as a non-invasive tool to study drug transport in controlled release systems. ESPI is shown to be a feasible tool to measure drug film permeability via comparison with an ordinary diaphragm cell. A specially designed cuvette was used in the release study: the polymeric film separated the donor and the receiving chambers of

A clinical evaluation of postoperative peritoneal lavage in the treatment of perforated appendicitis

In a comparative investigation, 369 patients operated upon for perforated appendicitis were studied retrospectively. During the period 1973-1979 181 patients with perforated appendicitis, treated at Sundsvall Hospital, were all given postoperative peritoneal lavage, whereas 188 patients with the same diagnosis treated at Skovde Hospital received no such treatment. Appendicectomy was performed in a

Development and evaluation of spherical molecularly imprinted polymer beads.

The majority of studies on molecularly imprinted polymers has until now been carried out on irregularly shaped particles prepared by grinding of polymer monoliths. The preparation procedures are time- and labor-consuming and produce particles of wide size distributions. To answer the need for fast and straightforward routes to spherical molecularly imprinted polymer beads, we have developed a meth

Temperature and concentration effects on supramolecular aggregation and phase behavior for poly(propylene oxide)-b-poly(ethylene oxide)-b-poly(propylene oxide) copolymers of different composition in aqueous mixtures, 1

The phase behavior (temperature vs composition) and microstructure for the two binary systems Pluronic 25R4 [(PO)(19)(EO)33(PO)(19)]-water and Pluronic 25R2 [PO)(21)(EO)(14)(PO)(21)]-water have been studied by a combined experimental approach in the whole concentration range and from 5 to 80 degreesC. The general phase behavior has been identified by inspection under polarized light. Precise phase

Detailed definition and interobserver agreement for the electrocardiographic Sclarovsky-Birnbaum ischemia grading system

A generally implementable method for predicting salvageability on the presenting electrocardiogram (ECG) in patients with acute myocardial infarction (AMI) would be of great clinical importance. ECG-derived Grades of Ischemia (1) have been proven useful in predicting the extent and severity of left ventricular dysfunction after anterior MI, estimating short and long-term prognosis, final infarct s

How best to fight that nasty itch - from new insights into the neuroimmunological, neuroendocrine, and neurophysiological bases of pruritus to novel therapeutic approaches

While the enormous clinical and psychosocial importance of pruritus in many areas of medicine and the detrimental effects of chronic 'itch' on the quality of life of an affected individual are widely appreciated, the complexity of this sensation is still often grossly underestimated. The current Controversies feature highlights this complexity by portraying pruritus as a truly interdisciplinary pr

Uterus and endometrium: Flow cytometric DNA analysis in endometriotic tissue compared to normal uterine endometrium

Endometriotic tissue sometimes shows an invasive pattern. but the growth regulation of the tissue is insufficiently characterized. In a research programme on factors regulating endometriotic growth, the DNA ploidy status and S-phase fraction (SPF) were studied. Fresh-frozen endometriotic tissue from 14 women and endometrium from 11 of them were studied using flow cytometry. A clear diploid pattern

Use of k-space segmentation in MR velocity mapping for rapid quantification of CSF flow

In this work, a k-space segmentation technique for quantitative studies of pulsatile cerebrospinal fluid (CSF) flow is suggested. Three k-space lines are sampled for each of two interleaved gradient-echo sequences (velocity-compensated and velocity-encoded) within each repetition interval. Nine cardiac phases are obtained at a heart rate of 60 bpm with maintained nominal resolution and a factor of

Interlaboratory evaluation of endotoxin analyses in agricultural dusts - comparison of LAL assay and mass spectrometry

Endotoxin exposure is associated with wheeze and asthma morbidity, while early life exposure may reduce risk of allergy and asthma. Unfortunately, it is difficult to compare endotoxin results from different laboratories and environments. We undertook this study to determine if lipopolysaccharide ( LPS) extraction efficiency could account for differences among laboratories. We generated and collect

Stem cell factor promotes mast cell survival via inactivation of FOXO3a-mediated transcriptional induction and MEK-regulated phosphorylation of the proapoptotic protein Bim

Mast cells are found in tissues throughout the body where they play important roles in the regulation of inflammatory responses. One characteristic feature of mast cells is their longevity. Although it is well established that mast cell survival is dependent on stem cell factor (SCF), it has not been described how this process is regulated. Herein, we report that SCF promotes mast cell survival th