Validity of self-reported duration of work postures obtained by interview

The aim of the study was to validate interview data concerning the duration of four work postures (1) sitting, (2) standing/walking with hands above shoulder level, (3) standing/walking with hands between shoulder and knuckle level, and (4) standing/walking with hands below knuckle level. The self-reported time spent in each posture was tested in relation to observations and technical measurements in 20 subjects during two full working days. The linear relationships between self-reports and observations were strong for the three postures; sitting (r²=0.55), hands above shoulder level (r²=0.58) and hands below knuckle level (r²=0.69). Thus, using this interview technique, self-reports concerning time spent in (1) sitting, (2) standing/walking with hands above shoulder level and, (3) standing/walking with hands below knuckle level may be accurate enough for studying these work postures in epidemiological studies.     

The Amyloid Forming Peptides Islet Amyloid Polypeptide and Amyloid β Interact at the Molecular Level

Epidemiological studies support a connection between the two common disorders, type-2 diabetes and Alzheimer’s disease. Both conditions have local amyloid formation in their pathogenesis, and cross-seeding between islet amyloid polypeptide (IAPP) and amyloid β (Aβ) could constitute the link. The bimolecular fluorescence complementation (BiFC) assay was used to investigate the occurrence of heterologous interactions between IAPP and Aβ and to compare the potential toxic effects of IAPP/Aβ, IAPP/IAPP, and Aβ/Aβ expression in living cells. Microscopy was used to confirm the fluorescence and determine the lysosomal, mitochondrial areas and mitochondrial membrane potential, and a FACS analysis was used to determine ROS production and the role for autophagy. Drosophila melanogaster expressing IAPP and Aβ was used to study their co-deposition and effects on longevity. We showed that the co-expression of IAPP and Aβ resulted in fluorophore reconstitution to the same extent as determined for homologous IAPP/IAPP or Aβ/Aβ expression. The BiFC(+)/BiFC(−) ratio of lysosomal area calculations increased in transfected cells independent of the vector combinations, while only Aβ/Aβ expression increased mitochondrial membrane potential. Expression combinations containing Aβ were necessary for the formation of a congophilic amyloid. In Drosophila melanogaster expressing IAPP/Aβ, co-deposition of the amyloid-forming peptides caused reduced longevity. The BiFC results confirmed a heterologous interaction between IAPP and Aβ, while co-deposits in the brain of Drosophila suggest mixed amyloid aggregates.     

Self-assembled structures of azobenzene amphiphiles: A new photorecording medium

The self-assembly of azobenzene amphiphiles by themselves and in the presence of a nonionic polymer has been studied. The conditions that yield homeotropic and uniaxial films, i.e., the optical properties of a single crystal, by spin-coating were identified. It is shown that these films constitute a very sensitive write and erase recording medium. © 1994 John Wiley & Sons, Inc.     

Intrathecal sufentanil compared with epidural bupivacaine analgesia in labour

Epidural analgesia for pain relief during labour has certain disadvantages including slow onset. However, intrathecal sufentanil provides rapid onset and well-controlled analgesia lasting 1-4 h. The aim of this study was to compare the analgesia and the side effects of intrathecal sufentanil with epidural bupivacaine during labour. In a randomized, double-blind and controlled trial 58 parturient women requesting analgesia during labour were studied. The patients received either intrathecal sufentanil 10 micrograms and epidural saline, or intrathecal saline and epidural bupivacaine 20 mg. Visual analogue scores (VAS) for pain, blood pressure, heart rate, respiratory rate, level of sedation and the incidence of pruritus and nausea were recorded. Pain scores were significantly lower between 5 and 90 min after injection in patients receiving intrathecal sufentanil. Pruritus was significantly more frequent among those receiving intrathecal sufentanil. The rapid onset and effective analgesia of intrathecal sufentanil may in certain situations be advantageous.     

Thin-film electro-acoustic sensors based on AlN and its alloys: possibilities and limitations

Sputter deposited aluminum nitride (AlN) thin films have played a central role for the successful development of the thin film electro-acoustic technology. The development has been primarily driven by one device—the thin film bulk acoustic resonator, with its primary use for high frequency filter applications for the telecom industry. Recently, increased piezoelectric properties in AlN through the alloying with scandium nitride have been identified both experimentally and theoretically. This opens up new possibilities for the thin film electro-acoustic technology. Here expectations and discussions are presented on acoustic FBAR sensor performance when based on AlN as well as on such AlN alloys to identify possible benefits and limitations. Inhere, the distinction is made between direct and in-direct (acoustic) use of the piezoelectric effect for sensor applications. These two approaches are described and compared in view of their advantages and possibilities. Especially, the indirect (or acoustic) use is identified as interesting for its versatility and good exploitation of the thin film technology to obtain highly sensitive sensor transducers. It is pointed out that the indirect approach can well be obtained internally in the piezoelectric material structure. Original calculations are presented to support the discussion.     

Frequency domain identification of continuous-time output error models, Part I: Uniformly sampled data and frequency function approximation

This paper treats several aspects relevant to identification of continuous-time output error (OE) models based on sampled data. The exact method for doing this is well known both for data given in the time and frequency domains. This approach becomes somewhat complex, especially for non-uniformly sampled data. We study various ways to approximate the exact method for reasonably fast sampling. While an objective is to gain insights into the non-uniform sampling case, this paper only gives explicit results for uniform sampling.     

Significance of fat supplemented diets on pork quality - Connections between specific fatty acids and sensory attributes of pork

The influence of two diets with different fatty acid compositions has been studied with regard to overall pork quality and significance of specific fatty acids on sensory attributes in fried chops and oven roasts. Twenty castrates and 20 females were in a balanced experimental set-up fed with a standard diet supplemented with α-tocopherol (200mg/kg feed) where the fat source was either 3% of palm oil or 3% rapeseed oil. After slaughter, despite differences in lipid composition and sensory attributes, no significant difference in overall meat quality parameters and flavour precursors was found. Comparison of the two diets showed that supplementation with rapeseed oil resulted in a significantly higher content of C18:3n-3 (polar lipid (PL), neutral lipid (NL)), C18:2n-6c (NL) and C20:2 (NL) in LD and C18:1n-9c, C18:2n-6c, C18:3n-3, C20:3n-3, C22:5n-3 in backfat, while supplementation with palm oil resulted in a higher content of C16:0 (NL), C16:1 (PL), C18:1n-9t (NL) in LD and C16:0, C17:0, C18:0, C16:1, C20:4n-6 in backfat. A positive and significant correlation between the contents of C18:2n-6c, C20:3n-6 in the PL fraction and the sensory attributes fried meat odour and sweet odour were found in fried pork chops from female pigs. Likewise, positive correlations were seen between the content of C18:1n-9c in the PL fraction and sensory attributes such as sourish odour, piggy odour and piggy flavour in whole oven roasts. These data substantiate the view that specific fatty acids in the PL fraction influences flavour attributes in pork.     

Nasal Mucosal Swelling in Relation to Low Air Exchange Rate in Schools

Abstract Acoustic rhinometry and hygienic measurements of indoor air pollutants were applied in a field study on nasal congestion among 27 subjects working in two primary schools. One school had natural ventilation only and a low air exchange rate (0.6 ac/h); the other had balanced mechanical ventilation and a high air exchange rate (5.2 ac/h). The minimal cross-sectional area and volume of the nasal cavity were estimated with acoustic rhinometry. The degree of swelling of the nasal mucosa was measured as the increase of the cross-sectional area after standardized application of nasal spray containing a decongestive adrenergic substance. Reports on weekly symptoms of nasal congestion were similar (33%) in both schools. A significantly increased decongestive effect was noticed for the minimal cross-sectional area (MCA2) among personnel in the school with a low air exchange rate. The difference between the schools in decongestive effect on MCA2 was 23%, corresponding to a 3% increase of MCA2 for a difference in personal outdoor airflow of one litre. Indoor concentration of volatile organic compounds (VOC), respirable dust, bacteria, moulds and VOCs of possible microbial origin (MVOC) were 2–8 times higher in the naturally ventilated school. In conclusion, inadequate outdoor air supply in schools may lead to raised levels of indoor air pollutants, causing a sub-clinical swelling of the nasal mucosa. Our results indicate that acoustic rhinometry could be applied in field studies, and that objective measurement of nasal decongestion might be a more sensitive measure of biological effects of indoor air pollution than symptom reporting.     

Method for multiresidue determination of halogenated aromatics and PAHs in combustion-related samples

Flue gas and fly ash samples have a complex composition. Thus, thorough extraction and selective cleanup prior to analysis are essential. This paper presents an evaluated method for determining halogenated dibenzo-p-dioxins (PXDD), halogenated dibenzofurans (PXDF), chlorinated biphenyls (PCB), chlorobenzenes (CBz), -phenols (CPh), dibenzo-p-dioxins (DD), dibenzofurans (DF), and polycyclic aromatic hydrocarbons (PAH) in a single sample. Since these combustion byproducts are ubiquitous, harmful environmental contaminants it is very important to obtain reliable assessments of them: especially specific PCDD/F and PCB congeners with Ah-receptor mediated toxicity. The reported method for this purpose includes techniques such as solid-phase extraction, Soxhlet-Dean-Stark extraction, cleanup using open liquid chromatographic columns, and finally GC/MS analysis/determination with quantification by the isotope dilution technique. The validation results presented here show good reproducibility for PXDD/F and PCB and are satisfactory for CPh, CBz, and PAH. An extraction efficiency test revealed that a nonpolar solvent did not completely extract a few analytes, i.e., diCPh and fluorene, which appear to require a more polar extraction agent. To pinpoint and minimize the loss of analytes, specific studies on reductions of their amounts during sample concentration were performed, showing that traditional rotary evaporation and nitrogen blow-down produce equally good results as a novel technique.