Designing a ‘green’ building: expanding ambitions through social learning

The process of creating a specific building – Miljøbygget in Trondheim, Norway – is analyzed in order to understand how the project team's ambitions expanded to embrace ‘green’ issues and create new targets. The decisions and roles of key actors are investigated regarding these goals and criteria. The analysis draws on two concepts. First, translation theory is used to highlight the potential role of new knowledge or technology that originates outside of the project. Second, the concept of social learning is employed to understand the process of expanding ambitions, developing goals and criteria within the project, and how this is related to the collective exploration, discovery and analysis of new practices. The wider implications are considered with respect to innovation in the construction industry. The project's initial moderate energy efficiency ambition was transformed, first into stricter energy efficiency goals, then into broader environmental aims. The resulting innovation is an ambition-enhancing, experience-based and enthusiasm-driven process of social learning in the project team, marked by interpersonal trust, including trust regarding competence and contractual relations. Translation efforts were also found to be important for bringing new knowledge into the project. The conclusion discusses some policy implications.     

A fast neural net training algorithm and its application to speech classification

This paper describes a fast training algorithm for feedforward neural nets, as applied to a two-layer neural network to classify segments of speech as voiced, unvoiced, or silence. The speech classification method is based on five features computed for each speech segment and used as input to the network. The network weights are trained using a new fast training algorithm which minimizes the total least squares error between the actual output of the network and the corresponding desired output. The iterative training algorithm uses a quasi-Newtonian error-minimization method and employs a positive-definite approximation of the Hessian matrix to quickly converge to a locally optimal set of weights. Convergence is fast, with a local minimum typically reached within ten iterations; in terms of convergence speed, the algorithm compares favorably with other training techniques. When used for voiced-unvoiced-silence classification of speech frames, the network performance compares favorably with current approaches. Moreover, the approach used has the advantage of requiring no assumption of a particular probability distribution for the input features.     

Forecasting models for tourism demand in city dominated and coastal areas

The paper uses Structural time series models to forecast the demand for tourism by nationality in coastal and city-dominated Spanish provinces. Intervention variables are introduced to take account of sudden shocks to tourism demand, such as the bombing of Libya and football's World Cup. The model demonstrates the considerable differences in demand by nationality, and in seasonality, which can occur at the subnational level. The Structural model generally provided more accurate forecasts than Box-Jenkins models. The results indicate that, ceteris paribus, the tourism demand growth rates in the Spanish provinces considered are unlikely to revert to their previous high levels.     

Improved training tolerance by supplementation with alpha-Keto acids in untrained young adults: a randomized, double blind, placebo-controlled trial

ABSTRACT: BACKGROUND: Exercise causes a variety of physiological and metabolic changes that can in turn reduce exercise tolerance. One of the potential mechanisms responsible for fatigue is "exercise-induced hyperammonemia". Previous studies have shown that supplementation with amino acids can increase training tolerance. The alpha-keto acids are biochemical analogs of amino acids and can be converted to amino acids through transamination, thus reducing the cellular ammonia level. This double blind, placebo-controlled study was designed to investigate the effects of alpha-keto acid supplementation (KAS) on training tolerance, training effect, and stress-recovery state. METHODS: Thirty-three untrained young male adults underwent four weeks of training (5 sessions/week; 30 minutes running at the individual anaerobic threshold followed by 3 x 3 minute sprints/each session). Throughout the 4 weeks of training and one week of recovery, subjects took alpha-ketoglutarate (AKG group, 0.2 g/kg/d, n=9), branched-chain keto acids (BCKA group, 0.2 g/kg/d, n=12) or isocaloric placebo (control group, n=12) daily. RESULTS: The 4th week training volume, maximum power output and muscle torque were higher in the AKG group (175+/-42 min, 412+/-49 Watts and 293+/-58 Newton meters, respectively, P<0.05) and the BCKA group (158+/-35, 390+/-29 and 273+/-47, P<0.05) than in the control group (92+/-70, 381+/-67 and 233+/-43). The general stress and emotional exhaustion as assessed by the rest-stress-questionnaire-sport after the 3rd week of training increased significantly in the control group (P<0.05), but not in the KAS groups. CONCLUSIONS: Under KAS, subjects could bear a higher training volume and reach a higher power output and peak muscle torque, accompanied by a better stress-recovery-state. Thus, KAS improves exercise tolerance and training effects along with a better stress-recovery state. Whether the improved training tolerance by KAS is associated with effects on ammonia homeostasis requires further observation.     

Seasonal reproductive patterns of female Gambusia holbrooki from two Florida lakes

Lake Apopka in central Florida (USA) is significantly contaminated with a variety of chemicals including anthropogenic nutrients, organochlorine pesticides like dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethylene (DDE), and multiple congeners of polychlorinated biphenyls (PCBs). Our laboratory has previously documented a number of reproductive abnormalities in alligators from Lake Apopka, compared with alligators captured from Lake Woodruff, a nearby reference lake. We conducted the present study to investigate if another native vertebrate, Gambusia holbrooki (eastern mosquitofish), is similarly affected. Adult female mosquitofish were collected from Lake Apopka and Lake Woodruff monthly for 16 months to document seasonal and lake-associated variation in reproductive patterns. In contrast to fish from Lake Woodruff (reference), females from Lake Apopka exhibited earlier and more synchronized spring ovarian recrudescence, increased body size, increased fecundity, increased adjusted hepatic weight, and more extreme fluctuations in muscle estradiol concentrations in most months. Endocrine disruption, consistent with other studies and Lake Apopka's pollution profile, is one explanation for these findings. Other environmental and physiological factors are also addressed. However, the higher fecundity among Apopka females suggests that, unlike Apopka alligators, Apopka mosquitofish are not impacted at the population level.     

Optoelectronic properties of a perylene substituted (cholesteryl)benzoateethynylene co-polymer

A perylene cholesteryl-benzoateethynylene co-polymer was synthesized by Sonogashira reaction and characterized by NMR, UV–Vis, static and dynamic fluorescence spectroscopy and cyclic voltammetry. The optical and electrochemical properties in solution are consistent with photoinduced energy transfer from the electron donor conjugated backbone to the electron acceptor perylene substituent. Photovoltaic properties are indeed found, even if the performance of the solar cells is quite low due to the formation of aggregates. The incorporation of (6,6)-phenyl C61–butyric acid methyl ester (PCBM), however, increases by an order of magnitude the efficiency of the prototype (from 10⁻⁴ to 10⁻³%) due to both better phase mixing and improved electrical continuity as supported by Atomic Force Microscopy (AFM) and Electrical Force Microscopy (EFM) studies.     

Self-assessed and actual Internet skills of people with visual impairments

The Internet can make available to people with a visual impairment information and services that are otherwise inaccessible. But do visually impaired users actually use common Internet applications and do they have the necessary skills? This article reports a two-part study addressing these questions. The first part was an interview study in which 73 young and 69 older Dutch people with a visual impairment were questioned about usage of applications such as e-mail, chat, and web forms, and their self-perceived competence. The young participants reported more frequent use of Internet applications and mentioned multiple goals (i.e., social and educational), compared to the older. Both groups considered themselves reasonably competent, with the young rating themselves higher. The second part was a case study with 20 young and 20 older participants from the first study, who performed common Internet tasks, using websites or applications that complied with accessibility guidelines. Task performance was analyzed in detail for demonstrated skills. Actual performance proved to be unrelated to self-rated competence. Moreover, the competence of both young and older participants fell far short of what active participation in society requires, especially for the more complex information and strategic skills. The success rate on the performance tasks was low. People with a visual impairment should receive extensive support for the acquisition of higher-level skills that are called upon when using Internet information and services in order to participate in society.     

A New Class of Fluorinated A2A Adenosine Receptor Agonist with Application to Last-Step Enzymatic [18F]Fluorination for PET Imaging

The A_2A adenosine receptor belongs to a family of G-coupled protein receptors that have been subjected to extensive investigation over the last few decades. Due to their prominent role in the biological functions of the heart, lungs, CNS and brain, they have become a target for the treatment of illnesses ranging from cancer immunotherapy to Parkinson's disease. The imaging of such receptors by using positron emission tomography (PET) has also been of interest, potentially providing a valuable tool for analysing and diagnosing various myocardial and neurodegenerative disorders, as well as offering support to drug discovery trials. Reported herein are the design, synthesis and evaluation of two new 5′-fluorodeoxy-adenosine (FDA)-based receptor agonists (FDA-PP1 and FDA-PP2), each substituted at the C-2 position with a terminally functionalised ethynyl unit. The structures enable a synthesis of ¹⁸F-labelled analogues by direct, last-step radiosynthesis from chlorinated precursors using the fluorinase enzyme (5′-fluoro-5′-deoxyadenosine synthase), which catalyses a transhalogenation reaction. This delivers a new class of A_2A adenosine receptor agonist that can be directly radiolabelled for exploration in PET studies.