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Mid-infrared polarization spectroscopy of C2H2: Non-intrusive spatial-resolved measurements of polyatomic hydrocarbon molecules for combustion diagnostics

Polarization spectroscopy in the mid-infrared (IRPS) has been applied to the detection of acetylene molecules making use of the asymmetric C-H stretching vibration at around 3 μm. The infrared laser pulses were produced through difference frequency generation in a LiNbO3 crystal pumped by a Nd:YAG and dye laser system. By directly probing the ro-vibrational transitions with IRPS, sensitive detecti

Synthesis of novel aggregating comb-shaped polyethers for use as polymer electrolytes

Polyethers having well-defined comb-shaped architectures were prepared by using poly(4-hydroxystyrene) (PHSt) as a multifunctional initiator for graft polymerization of either ethylene oxide (EO) or a mixture of EO and propylene oxide (PO). The grafting process was performed in 1,4-dioxane using NaH as ionizer for the PHSt hydroxyl groups. The precursor PHSt was prepared by first polymerizing 4-te

Treatments with losartan or enalapril are equally sensitive to deterioration in renal function from cyclooxygenase inhibition.

Background: The beneficial effects of angiotensin converting enzyme (ACE)-inhibitors are in part mediated through the inhibition of the degradation of the vasodilator bradykinin. The bradykinin effect is counteracted by cyclooxygenase-inhibitors. Angiotensin receptor blockers (ARBs) do not affect bradykinin. Aims: To test the hypothesis that renal counteraction from a cyclooxygenase-inhibitor, dic

Downregulation of peroxisome proliferator-activated receptors (PPARs) in nasal polyposis

Background: Peroxisome proliferator-activated receptor (PPAR) alpha, beta delta and gamma are nuclear receptors activated by fatty acid metabolites. An anti-inflammatory role for these receptors in airway inflammation has been suggested. Methods: Nasal biopsies were obtained from 10 healthy volunteers and 10 patients with symptomatic allergic rhinitis. Nasal polyps were obtained from 22 patients,

alpha(1)-Antitrypsin Inhibits Epithelial Na+ Transport In Vitro and In Vivo

A variety of studies have shown that Na+ reabsorption across epithelial cells depends on the protease-antiprotease balance. Herein, we investigate the mechanisms by which alpha(1)-antitrypsin (A1AT), a major anti-serine protease in human plasma and lung epithelial fluid and lacking a Kunitz domain, regulates amiloride-sensitive epithelial Na+ channel (ENaC) function in vitro and in vivo. A1AT (0.0

Residues from transmembrane helices 3 and 5 participate in leukotriene B-4 binding to BLT1

Leukotrienes are inflammatory mediators that bind to seven transmembrane, G-protein-coupled receptors (GPCRs). Here we examine residues from transmembrane helices 3 and 5 of the leukotriene B-4 (LTB4) receptor BLT1 to elucidate how these residues are involved in ligand binding. We have selected these residues on the basis of (1) amino acid sequence analysis, (2) receptor binding and activation stu

Nutritional aspects in patients with functional gastrointestinal disorders and motor dysfunction in the gut. Working team report of the Swedish Motility Group (SMoG)

In reviews regarding the management of patients with functional gastrointestinal disorders and motility disturbances within the gut nutritional aspects and dietary advice is often put forward as being of great importance. However, there are relatively few high-quality, interventional studies in the literature supporting an important role for general dietary advice to improve symptoms in these pati

Monitoring of polychlorinated biphenyls in human blood plasma: methodological developments and influence of age, lactation, and fish consumption

Human plasma samples from 50 wives of fishermen have been analyzed with respect to PCBs. The non-ortho-substituted PCB congeners CB-126 and CB-169 were determined by mass spectrometry in negative ion chemical ionization mode, which demonstrated a limit of detection of 30 fg. The recoveries of the internal standards used for determination of ortho-substituted CBs were approximately 95%. Two methods

Acoustic differential extraction for forensic analysis of sexual assault evidence.

Forensic DNA analysis of samples obtained from sexual assault evidence relies on separation of male and female components of the recovered genetic material. The conventional separation method used by crime laboratories, differential extraction (DE), is one of the most time-consuming sample preparation steps, requires extensive sample handling, is difficult to automate, and often results in ineffic

Occupational exposure to organic dust, microorganisms, endotoxin and peptidoglycan among plants processing workers in Poland

The objective of present work was to determine and compare the components of bioaerosol in several sectors of plant processing industries. The Study was conducted in 10 Facilities engaged in herb and grain processing, flax threshing, grain storing, baking, and cereals production. The air samples were taken on glass fibre litters with an AS-50 sampler. We determined the concentrations of airborne m

The potential of isothermal calorimetry in monitoring and predicting quality changes during processing and storage of minimally processed fruits and vegetables

We review the potential of isothermal calorimetry as an analytical tool to provide an integrated view of the effect of different processing steps on the quality and shelf life of minimally processed fruits and vegetables. Variations in processing operations involved in product development in the food industry are studied through a factory scenario to show the versatility of the technique in monito

Theory of the ultrafast nonlinear response of terahertz quantum cascade laser structures

Using density matrix theory, the linear and ultrafast nonlinear optical properties of a recently developed terahertz quantum cascade laser are investigated. All relevant excitation regimes, from coherent Rabi flopping up to the scattering dominated stationary response, are covered by the theory. It is shown that the coherence transfer between different periods is important to describe optical effe

The role of low grade inflammation as measured by C-reactive protein levels in the explanation of socioeconomic differences in carotid atherosclerosis.

Background: The role of inflammation as part of the explanation of socioeconomic differences in carotid atherosclerosis has not been specifically investigated. Methods and Results: The associations between socioeconomic position (SEP), C-reactive protein (CRP), and preclinical carotid atherosclerosis were investigated in a general population sample of 3921 middle-aged Swedish men and women. Common

Ancient bacteria show evidence of DNA repair

Recent claims of cultivable ancient bacteria within sealed environments highlight our limited understanding of the mechanisms behind long-term cell survival. It remains unclear how dormancy, a favored explanation for extended cellular persistence, can cope with spontaneous genomic decay over geological timescales. There has been no direct evidence in ancient microbes for the most likely mechanism,

Papillary secretion. Diagnostic assessment and treatment.

Papillary secretion is a common symptom in the breast clinic with many different underlying causes like intraductal papilloma, mammary duct ectasia, infected cysts and abscesses, breast cancer/carcinoma in situ (CIS) and rarely pituitary adenoma. The association with cancer/CIS is one of the two main concerns of the patient and must always be ruled out. The second item is that spontaneous and ongo