Indoor environment quality contracts in building projects

The scientific literature is replete with examples that indicate that poor indoor conditions at workplaces reduce work performance and increase short-term sick leave. To address good indoor environment quality (IEQ), strategic and practical design decisions are needed in the early phase of the building process to ensure successful implementation. However, current procurement practices are hampered by fragmentation, long subcontract chains and vague performance requirements. A preliminary study is undertaken that focuses on developing a method of contracting that enables the attainment and verification of the desired IEQ. Using a review of international research and practices, existing commissioning methods and contract procedures are identified for their attention to IEQ. A contract procedure is proposed that fosters agreement on indoor environment between building owners and tenants, and which directs a building project to give users the guarantee of indoor condition. To make a pre-lease contract agreement that includes IEQ, the factors having an influence on the IEQ chain must be included in all building contracts such as those of design, purchase, and operation and maintenance. Thus, the requirements of IEQ require their incorporation into every phase of the building project. The main elements in these contracts, in addition to the requirements of IEQ, are those verifying quality, bonuses and sanctions.

La littérature scientifique est riche en exemples qui montrent que la médiocrité des conditions intérieures sur le lieu de travail réduit les performances opérationnelles et augmente les absences de courte durée pour raisons de santé. Pour obtenir un environnement intérieur de bonne qualité (IEQ), il faut, dès le début du processus de construction, prendre des décisions d'ordre stratégique et pratique en vue d'une mise en ?uvre réussie. Or, la fragmentation, les longues chaînes de contrats de sous-traitance et le manque de précision des impératifs de performance sont autant d'obstacles aux pratiques d'approvisionnement actuelles. Une étude préliminaire est entreprise qui porte, pour l'essentiel, sur le développement d'un mode de réalisation permettant de satisfaire et de vérifier la qualité de l'environnement intérieur recherchée. S'appuyant sur une analyse des pratiques et de la recherche au niveau international, l'auteur recense les méthodes de mise en service et les procédures contractuelles existantes en fonction de l'intérêt porté à l'IEQ. Il est proposé une procédure contractuelle qui encourage les accords en matière d'environnement intérieur entre propriétaires de bâtiments et occupants et qui prescrit un projet de construction offrant aux utilisateurs la garantie d'un environnement intérieur satisfaisant. Pour conclure une convention contractuelle, préalablement au bail de location, qui prévoit l'IEQ, il faut inclure les facteurs ayant une influence sur la chaîne IEQ dans tous les contrats de bâtiments, comme la conception, l'approvisionnement, l'exploitation et la maintenance. Les exigences en matière d'IEQ nécessitent donc qu'elles soient intégrées à toutes les phases d'un projet de bâtiment. Les principaux éléments dans ces contrats, outre les exigences d'IEQ, sont ceux qui vérifient la qualité, les primes et les sanctions.     

Interpretation of doping phenomena in high-T c superconductors

On the basis of an indirect-exchange pairing mechanism of superconductivity we present a consistent interpretation of doping phenomena in both hole-doped as well as electron-doped high-T _c superconductors. We argue that in all these materials the unifying feature is the existence of a correlated narrow band of electron states formed due to doping. Numerous experimental evidences for the occurrence of such a band (reflectivity, thermoelectric power, electrical resistivity, X-ray absorption, point-contact tunneling etc.) now exist. Assuming the existence of such a band it was earlier shown that the indirect-exchange (superexchange) coupling between electrons in this band via closed-shell oxygen anions is attractive in the s-wave channel and leads to high-T _c superconductivity. Within the framework of this pairing mechanism, recent doping experiments (for both types of doping) can be given a unified interpretation. In addition, definitive predictions of the doping conditions under which critical temperatures are expected to enhance, are made.     

Fibre mortar composites in fire conditions

A small-scale test series was carried out using the heating system (radiant exposure) of a cone calorimeter to detect any differences in the way different fibres affect the thermal properties of a standard mortar. The fibres were different polypropylene, polyacrylonitrile, aramide, carbon or steel. Fibres affect the release of moisture from the fibre mortar material. Local pressures caused by water vaporization due to rapid heating can be decreased by incorporating fibres. Fibres have a weak insulating effect. However, use of polyacrylonitrile fibres in mortar may increase the risk to spalling under rapid thermal exposure such as fire. The moisture level in specimens is highly significant for their thermal properties and hence their fire behavior.     

Approximate Boyer-Moore String Matching for Small Alphabets

Recently a new variation of approximate Boyer-Moore string matching was presented for the k-mismatch problem. The variation, called FAAST, is specifically tuned for small alphabets. We further improve this algorithm gaining speedups in both preprocessing and searching. We also present three variations of the algorithm for the k-difference problem. We show that the searching time of the algorithms is average-optimal and the preprocessing also has a lower time complexity than FAAST. Our experiments show that our algorithm for the k-mismatch problem is about 30% faster than FAAST and the new algorithms compare well against other state-of-the-art algorithms for approximate string matching.     

Exploring the Ion Channel TRPV2 and Testicular Macrophages in Mouse Testis

The cation channel TRPV2 is known to be expressed by murine macrophages and is crucially involved in their functionality. Macrophages are frequent cells of the mouse testis, an immune-privileged and steroid-producing organ. TRPV2 expression by testicular macrophages and possible changes associated with age or inflammation have not been investigated yet. Therefore, we studied testes of young adult and old wild-type (WT) and AROM⁺ mice, i.e., transgenic mice overexpressing aromatase. In these animals, inflammatory changes are described in the testis, involving active macrophages, which increase with age. This is associated with impaired spermatogenesis and therefore AROM⁺ mice are a model for male infertility associated with sterile inflammation. In WT animals, testicular TRPV2 expression was mapped to interstitial CD206⁺ and peritubular MHC II⁺ macrophages, with higher levels in CD206⁺ cells. Expression levels of TRPV2 and most macrophage markers did not increase significantly in old mice, with the exception of CD206. As the number of TRPV2⁺ testicular macrophages was relatively small, their possible involvement in testicular functions and in aging in WT mice remains to be further studied. In AROM⁺ testis, TRPV2 was readily detected and levels increased significantly with age, together with macrophage markers and TNF-α. TRPV2 co-localized with F4/80 in macrophages and further studies showed that TRPV2 is mainly expressed by unusual CD206⁺MHC II⁺ macrophages, arising in the testis of these animals. Rescue experiments (aromatase inhibitor treatment and crossing with ERαKO mice) restored the testicular phenotype and also abolished the elevated expression of TRPV2, macrophage and inflammation markers. This suggests that TRPV2⁺ macrophages of the testis are part of an inflammatory cascade initiated by an altered sex hormone balance in AROM⁺ mice. The changes in testis are distinct from the described alterations in other organs of AROM⁺, such as prostate and spleen. When we monitored TRPV2 levels in another immune-privileged organ, namely the brain, we found that levels of TRPV2 were not elevated in AROM⁺ and remained stable during aging. In the adrenal, which similar to the testis produces steroids, we found slight, albeit not significant increases in TRPV2 in both AROM⁺ and WT mice, which were associated with age. Thus, the changes in the testis are specific for this organ.     

Endotoxins associated with cyanobacteria and their removal during drinking water treatment

The aim of this study was to investigate endotoxin concentrations in cyanobacterial water blooms and strains, and to assess the removal of endotoxins during drinking water treatment. Endotoxin concentrations were measured from 151 hepatotoxic, neurotoxic and non-toxic cyanobacterial water blooms by using Limulus amebocyte lysate (LAL) assay, and the results were compared to bacterial data. Endotoxin activities ranged from 20 to 3.8 x 10(4) endotoxin units (EU) per ml. Endotoxicity of the samples correlated with phycobiliprotein concentration that was used to assess cyanobacterial abundance, heterotrophic plate count, and Aeromonas spp. but it did not correlate with the number of coliforms or streptococci. The high endotoxin concentrations occasionally detected in the water bloom samples were probably due to Gram negative bacteria that existed together with cyanobacteria since the 26 axenic cyanobacterial strains from different genera that were studied showed very low endotoxin activity. No differences in endotoxin activity were detected between hepatotoxic, neurotoxic and non-toxic strains. Removal of endotoxins during drinking water treatment was studied at nine waterworks that previously had been associated with high numbers of cyanobacteria and that used different processes for water purification. Endotoxin concentration in raw waters ranged from 18 to 356 EU ml(-1). The treatment processes reduced 59-97% of the endotoxin activity; in the treated water the concentration ranged from 3 to 15 EU ml(-1). The most significant reduction occurred at the early stages of water treatment, during coagulation, settling and sand filtration. Activated carbon filtration either increased or had no effect on endotoxin concentration. Ozonation and chlorination had little effect on the endotoxin concentrations.     

Nanofibre-based bilayer biopolymer films: enhancement of antioxidant activity and potential for food packaging application

This study aimed to enhance the antioxidant property of biopolymer film without the incorporation of external agents. The active bilayer film with improved antioxidant activity has been developed by electrospinning zein, a prolamine of corn as nanofibre (average diameter of 286 nm) on solvent cast chitosan film. Zein nanofibres exhibited a slight increase in antioxidant activity as compared to solvent cast zein film. But, zein nanofibre coating on chitosan films significantly improved its antioxidant activity from 12.41% to 44.17%. The developed bilayer films were evaluated for its ability to prevent browning in minimally processed apple slices and compared with those of chitosan and zein films plasticised with polyethylene glycol. Higher surface to volume ratio and better affinity of zein nanofibres in the bilayer film helped enhance its anti-browning ability. Thus, zein nanofibre-coated chitosan bilayer films can be used as an effective anti-browning packaging material for the packing of minimally processed fruits.     

Detection of gaseous species during KCl-induced high-temperature corrosion by the means of CPFAAS and CI-APi-TOF

Two different analytical approaches—collinear photofragmentation and atomic absorption spectroscopy (CPFAAS) and chemical ionization atmospheric pressure interface time-of-flight mass spectrometer (CI-APi-TOF)—were applied to detect and identify the online gaseous KOH and HCl formed in the addressed high-temperature reactions. Samples of pure KCl, KCl+Cr, KCl+Fe, and KCl+316 L were studied at 550°C under dry and humid conditions with varying oxygen concentrations. The goal was to shed more light on the gas-phase chemistry during KCl-induced corrosion under conditions relevant to biomass combustion. CI-APi-TOF proved to be a valuable tool for high-temperature corrosion studies: HCl was identified to have formed during the reactions under humid conditions. On the contrary, despite the known sensitivity of CPFAAS, the formation of KOH could not be verified in any of the performed measurements.