A Danish case: portfolio evaluation and its impact on energy efficiency policy

A political agreement from 2005 stated that an evaluation of the entire Danish energy efficiency policy portfolio must be carried out before the end of 2008, with the aim to assess the following: (1) Is the policy portfolio sufficient to meet the energy efficiency targets? (2) Do the policies enable the national goals to be met in a cost-effective manner? (3) Is the overall design of the policy portfolio appropriate? The evaluation gave recommendations on how to improve and develop the portfolio, mainly using cost-effectiveness as criteria. The evaluation was completed in December 2008, and this paper presents the main findings and the subsequent impact on Danish policy. A key lesson learned is the importance of including all energy efficiency policies in the evaluation. Examining the entire portfolio of policies (as opposed to only selected policies) gave way to findings that would otherwise not have been captured. With its broad perspective, the evaluation found that the policy instruments prioritised the commercial and industrial sectors less than the household and public sectors. The recommendations made by the authors contributed to the implementation of new taxes for the commercial and industrial sectors together with the reform of the Electricity Saving Trust to a Centre for Energy Savings charged with energy savings within all sectors, except transport—both which have been important steps towards a more cost-effective solution.     

Estimation of material functions using system identification techniques

Material properties of an elastic material are characterized by the elastic modulus, which is real-valued and constant. For viscoelastic materials, such as plastics and polymers, the relationship between stress and strain is instead dynamic, and characterized by the complex-valued and frequency-dependent complex modulus. It is in this paper described how system identification techniques can be used to determine the complex modulus using strain data from wave propagation experiments on a test specimen. Modeling, derivation of estimators, and analysis of their numerical and statistical properties are included. Identifiability and experimental design are examined in some detail. Several practical examples are presented using real-world data, and a number of extensions are outlined.     

A comparative study of the electrical and mechanical properties of epoxy nanocomposites reinforced by CVD- and arc-grown multi-wall carbon nanotubes

In this study, three different types of multi-wall carbon nanotubes (MWCNTs) were compared as nanostructured reinforcements in epoxy polymers: commercially available CVD-MWCNTs, synthesised in an industrial process, aligned-CVD-MWCNTs and arc-grown MWCNTs, both obtained from a lab-scale processes. The nanocomposite properties were characterised by means of electron microscopy, rheological, electrical and mechanical methods. Industrial CVD-MWCNTs are favourable for the implication of an electrical conductivity in the epoxy due to their high tendency to form conducting networks. The less entangled structure of aligned-CVD-MWCNTs turns out to be favourable for an easy dispersion and low viscosity in epoxy at similar conductivities compared to the CVD-MWCNTs. Additionally, they provide the highest increase in fracture toughness (∼17%). Arc-grown MWCNTs do not offer any electrical conductivity in epoxy without sufficient purification methods. Their high level of impurities and short length further complicate the transfer of their good electrical and mechanical properties into the nanocomposite.     

Relations between anxiety sensitivity, distress tolerance, and fear reactivity to bodily sensations to coping and conformity marijuana use motives among young adult marijuana users.

The present investigation examines anxiety sensitivity, distress tolerance, and fear reactivity to bodily sensations in relation to Coping and Conformity marijuana use motives among a sample of young adult marijuana users (n = 135; 46.7% women; Mage = 20.45, SD = 5.0). After controlling for current marijuana use frequency (past 30 days), daily cigarette smoking rate, average volume of alcohol used over the past year, negative affectivity, and other marijuana use motives, anxiety sensitivity was significantly and uniquely associated with Coping and Conformity motives for marijuana use. Distress tolerance evidenced significant and unique incremental relations to Coping motives, whereas fear reactivity to bodily sensations was unrelated to any marijuana use motive. These results provide novel information related to the role of emotional sensitivity and tolerance factors as they pertain to specific types of motives for marijuana use among young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Impact of Polyoxyethylene Sorbitan Surfactants in the Microstructure and Rheological Behaviour of Emulsions Made With Melted Fat From Cupuassu (<Emphasis Type="Italic">Theobroma grandiflorum</Emphasis>)

Cupuassu fat is a good candidate for partial substitution of cocoa butter in many products, including emulsions. However, for such use it is necessary to know the characteristics of the products prepared with cupuassu fat. Therefore, the main goal of this work is to characterize emulsions prepared with cupuassu fat using the surfactants Tween^® 60, Tween^® 80 and Tween^® 85 as emulsifiers. The emulsions were prepared at 43 °C with addition of 0.5 or 1.5 % (w/v) of surfactant and compared with an emulsion without surfactant. All emulsions were analysed by conductivity, stability, pH, optical microscopy, rheology and oxidative stability. It was verified that the emulsions prepared with Tween^® 60 and Tween^® 80 have higher stability, smaller droplet size and higher apparent viscosity. Also, these properties are positively influenced by the concentration of the surfactant. On the other hand, emulsions prepared with Tween 85 or without surfactant reached unsatisfactory results. The rheological behaviour of the emulsions was adequately described by both Herschel-Bulkley and Mizhari-Berki models revealing pseudoplastic character. These emulsions also present strong gel behaviour, with storage modulus higher than loss modulus. In conclusion, cupuassu fat can be used as oil phase for emulsions products and this characterization helps to understand their behaviour in order to increase their use in food industry.     

Colloidal thiophosphorus calcium salt as antiwear additive

This paper describes the synthesis of an oil-soluble colloidal calcium thiophosphate by a direct route. It consists of the reaction of calcium oxide or hydroxide with tetraphosphorus decasulphide and water in the presence of a surfactant such as a calcium alkylaryl sulphonate in an organic medium. Reaction and micellisation occurred simultaneously according to a one-step process. The product is characterised by a high calcium, phosphorus and sulphur content. The colloidal nature of the product has been confirmed by dialysis. The ³¹P-NMR spectrum showed signals characteristic of a blend of different calcium thiophosphates, plus calcium phosphate. The product could be defined as a core of different calcium (thio)phosphates surrounded by a calcium alkylaryl sulphonate shell, according to a reverse micelle type association in oil. This compound was evaluated as an antiwear additive in a 130 Neutral Solvent mineral oil by anti-wear and extreme-pressure four-ball tests. The extreme-pressure characteristics depend on the concentration of mineral colloidal core in oil. The antiwear properties are a function not only of the concentration, but also of the colloidal core/surfactant shell ratio. Thermogravimetric analysis of these colloidal species shows a weight loss in the 350°C to 450°C range, due to surfactant degradation. The further evolution of weight loss up to 900°C demonstrates the high thermal stability of the colloidal calcium (thio)phosphate core.     

Antibiotic susceptibility of Bifidobacterium thermophilum and Bifidobacterium pseudolongum isolates from animal sources

The widespread use of antimicrobial substances has led to resistant populations of microorganisms in several ecosystems. In animal husbandry, the application of antibiotics has contributed to resistance development in pathogenic and commensal bacteria. These strains or their resistance genes can be spread along several ecological routes, including the food chain. Antibiotic resistance is important in terms of the safety of industrial strains, such as probiotics for food and feed. Bifidobacterium thermophilum and Bifidobacterium pseudolongum are known to comprise the major part of the bifidobacterial microbiota in the gut and feces of cattle and pigs. In this study, the antimicrobial susceptibility in bifidobacterial isolates of these species was investigated. Isolates from the beef and pork production chain were identified and typed to strain level, and the antimicrobial susceptibility level was tested to a set of antibiotics. Isolates with low susceptibility levels were screened by PCR for already described resistance genes. Strains atypically resistant to clindamycin, erythromycin, and tetracycline were determined. The resistance genes tet(O), tet(W), and erm(X) were detected in the bifidobacterial species that were examined.     

Development of a selective broth medium for the detection of injured Campylobacter jejuni by capacitance monitoring

The purpose of these studies was to develop a conductimetric method for the rapid detection of Campylobacter jejuni. Numerous basal medium components were analyzed to develop a growth-enhancing broth medium for detection of freeze-injured Campylobacter cells using a conductimetric system. The final medium was composed of a modified Campy-Line agar from which the agar and triphenyltetrazolium chloride were removed and the amino acid, L-arginine was added. Pure isolates of C. jejuni. (frozen and thawed to produce stressed cells) were utilized to test the detection methodology. Monitoring of significant changes in the capacitance signal was found suitable for detection of Campylobacter proliferation. Using stressed pure cultures, Campylobacter growth was repeatedly detected at very low inoculum levels (about one cell per well). There was a direct linear relationship between detection times (DTs) and the initial inoculum level. For example, using a single strain, the mean DT (n = 20) at the 10 CFU/ml inoculum level was 28.6 h, with 100% of the inoculated wells detecting. The mean DTs at the 100, 1,000, and 10,000 CFU/ml inoculum levels were 24.9, 21.4, and 17.0 h, respectively. This study demonstrates that conductimetric methods can be utilized for the rapid detection of C. jejuni.     

Transcriptome Analyses of Adipose Tissue Samples Identify EGFL6 as a Candidate Gene Involved in Obesity-Related Adipose Tissue Dysfunction in Children

Obesity develops early in childhood and is accompanied by early signs of adipose tissue (AT) dysfunction and metabolic disease in children. In order to analyse the molecular processes during obesity-related AT accumulation in children, we investigated genome-wide expression profiles in AT samples, isolated adipocytes, and stromal vascular fraction (SVF) cells and assessed their relation to obesity as well as biological and functional AT parameters. We detected alterations in gene expression associated with obesity and related parameters, i.e., BMI SDS, adipocyte size, macrophage infiltration, adiponectin, and/or leptin. While differential gene expression in AT and adipocytes shared an enrichment in metabolic pathways and pathways related to extracellular structural organisation, SVF cells showed an overrepresentation in inflammatory pathways. In adipocytes, we found the strongest positive association for epidermal growth factor-like protein 6 (EGFL6) with adipocyte hypertrophy. EGFL6 was also upregulated during in vitro adipocyte differentiation. In children, EGFL6 expression was positively correlated to parameters of AT dysfunction and metabolic disease such as macrophage infiltration into AT, hs-CRP, leptin levels, and HOMA-IR. In conclusion, we provide evidence for early alterations in AT gene expression related to AT dysfunction in children and identified EGFL6 as potentially being involved in processes underlying the pathogenesis of metabolic disease.