Frost formation and condensation in stone–wool insulations

This paper reports on a laboratory experiment concerning frost formation and moisture condensation in fibrous insulation based on stone–wool. Frost formation in samples of stone–wool open to air was noted in cases when temperature field over the specimen was between +20 and ?20 °C and air on the warm side was saturated with moisture.Frost accumulated with time in the part of the specimen facing the cold air. In the part of the specimen facing the warm humid air condense formation occurred. In this part the material had moisture content considerably higher than what could be anticipated from data such as moisture isotherms.Border between frost and liquid condensate was quite sharp in the specimens of higher density. Moisture content mass by mass has an upward trend with decreasing density of the material sample. Moisture resistance factor was found to be quite high at these circumstances. Reason for this is not clear.     

The social bookmark and publication management system bibsonomy

Social resource sharing systems are central elements of the Web 2.0 and use the same kind of lightweight knowledge representation, called folksonomy. Their large user communities and ever-growing networks of user-generated content have made them an attractive object of investigation for researchers from different disciplines like Social Network Analysis, Data Mining, Information Retrieval or Knowledge Discovery. In this paper, we summarize and extend our work on different aspects of this branch of Web 2.0 research, demonstrated and evaluated within our own social bookmark and publication sharing system BibSonomy, which is currently among the three most popular systems of its kind. We structure this presentation along the different interaction phases of a user with our system, coupling the relevant research questions of each phase with the corresponding implementation issues. This approach reveals in a systematic fashion important aspects and results of the broad bandwidth of folksonomy research like capturing of emergent semantics, spam detection, ranking algorithms, analogies to search engine log data, personalized tag recommendations and information extraction techniques. We conclude that when integrating a real-life application like BibSonomy into research, certain constraints have to be considered; but in general, the tight interplay between our scientific work and the running system has made BibSonomy a valuable platform for demonstrating and evaluating Web 2.0 research.     

Cyclic voltammetric studies on a monocrystalline antimony electrode

Monocrystalline antimony electrodes have been studied by cyclic voltammetry in solutions containing sodium nitrate and one of the following complexing agents: TRIS [Tris (hydroxymethyl) amino methane], orthophosphate, EDTA (ethylenedinitrilo tetraacetic acid) or tartrate at an ionic strength of 0.16 The results have been compared to results obtained in a solution containing only sodium nitrate, which has been shown previously to have no effect on the Sb-electrode potential in the pH range 2–10 which was studied.The results indicate formation of soluble complexes with the ligands studied. Competing reactions seem to take place in the solutions containing orthophosphate (and presumably EDTA). The reactions between Sb(III) and TRIS or orthophosphate seem to be reversible for all practical purposes.The complex formation between Sb(III) and TRIS seems to be weak since the behaviour of the electrode is very similar in TRIS and in pure nitrate solution. TRIS is therefore suitable as a buffer for calibrating antimony electrodes.     

Acute segmental gastro-intestinal gangrene probably of clostridial origin. Report of a case

A 29-year-old female suffering from acute terminal ileitis was subjected to laparotomy undertaken on the tentative diagnosis of acute appendicitis. The appendix was found to be normal and was removed. The course was complicated with segmental gastro-intestinal gangrene with fatal outcome. The involvement of histotoxic clostridial infection as a causative factor is discussed.     

Evaluation of a Large Ge(Li) Detector for Low-Level Radionuclide Analysis

An evaluation of a 26.3% relative efficiency Ge(Li) detector for low-level radionuclide analysis has been made. The detector performance for sources mounted at the detector end cap was compared with the other smaller Ge(Li) detectors and with an opposed Ge(Li) two detector system. Factors studied included resolution, peak-to-Compton ratios, background, detection efficiency at the end cap, source geometry, and relative sensitivity. The 26.3% relative efficiency detector was found to give superior end cap efficiencies, peak-to-Compton ratios, and relative sensitivities without sacrificing performance in the other factors studied.     

Differences in cyclists and car drivers exposure to air pollution from traffic in the city of Copenhagen.

It has frequently been claimed that cycling in heavy traffic is unhealthy, more so than driving a car. To test this hypothesis, teams of two cyclists and two car drivers in two cars were equipped with personal air samplers while driving for 4 h on 2 different days in the morning traffic of Copenhagen. The air sample charcoal tubes were analysed for their benzene, toluene, ethylbenzene and xylene (BTEX) content and the air filters for particles (total dust). The concentrations of particles and BTEX in the cabin of the cars were 2-4 times greater than in the cyclists' breathing zone, the greatest difference being for BTEX. Therefore, even after taking the increased respiration rate of cyclists into consideration, car drivers seem to be more exposed to airborne pollution than cyclists.     

Alpha-Synuclein Autoimmune Decline in Prodromal Multiple System Atrophy and Parkinson’s Disease

Multiple-system trophy (MSA) and Parkinson’s Disease (PD) are both progressive, neurodegenerative diseases characterized by neuropathological deposition of aggregated alpha-synuclein (αSyn). The causes behind this aggregation are still unknown. We have reported aberrancies in MSA and PD patients in naturally occurring autoantibodies (nAbs) against αSyn (anti-αSyn-nAbs), which are important partakers in anti-aggregatory processes, immune-mediated clearance, and anti-inflammatory functions. To elaborate further on the timeline of autoimmune aberrancies towards αSyn, we investigated here the Immunoglobulin (Ig) affinity profile and subclass composition (IgG-total, IgG1-4 and IgM) of anti-αSyn-nAbs in serum samples from prodromal (p) phases of MSA and PD. Using an electrochemiluminescence competition immunoassay, we confirmed that the repertoire of high-affinity anti-αSyn-nAbs is significantly reduced in pMSA and pPD. Further, we demonstrated that pPD had increased anti-αSyn IgG-total levels compared to pMSA and controls, concordant with increased anti-αSyn IgG1 levels in pPD. Anti-αSyn IgG2 and IgG4 levels were reduced in pMSA and pPD compared with controls, whereas anti-αSyn IgG3 levels were reduced in pMSA compared to pPD and controls. The results indicate that the impaired reactivity towards αSyn occurs prior to disease onset. The apparent lack of high-affinity anti-αSyn nAbs may result in reduced clearance of αSyn, leading to aggregation of the protein. Thus, this study provides novel insights into possible causes behind the pathogenesis in synucleinopathies such as MSA and PD.     

Welding methods with reduced fire hazard for single-ply polymer-modified bituminous roofing materials

Fire accidents caused by the use of open gas torching during roof-installation work have led to considerable costs, and between 1985 and 1990 such costs reached 249 Million SKr. The Swedish Fire Protection Association together with the roofing contractors association reached agreement on the education and certification of roofers. Meanwhile, the insurance companies started to demand welding methods with lower temperatures and less fire hazard. This resulted in a marked decrease in fires and in a sharp decrease in the amounts paid out by insurance companies (187 million SKr in 1989, 25 million SKr in 1990 and 2.4 million SKr in 1991). This paper summarises the results of a study of the new welding methods, replacing conventional gas torching, for the installation of polymer-modified bituminous roof-coverings on flat roofs. In all eight different welding methods were evaluated in Stockholm during the installation in October 1992. Four different products of single-ply roof-coverings, namely one of atactic polypropylene (APP)-modified bitumen and three of styrene–butadiene–styrene copolymer (SBS)-modified bitumen, were studied. The study comprises temperature measurements during welding jobs on-site to evaluate fire hazard, and laboratory measurements of T-peel strength of the seams in order to evaluate the quality of the seam samples prepared on-site. The results showed that by these new welding methods a remarkable decrease in temperatures by weld was made without any significant change in the quality of the seams. However, the mechanical strength of the seam was related to welding speed, which should be limited to form sufficiently strong seams using heat welding.