Do graphical overviews facilitate or hinder comprehension in hypertext?

Educational hypertexts usually include graphical overviews, conveying the structure of the text schematically with the aim of fostering comprehension. Despite the claims about their relevance, there is currently no consensus on the impact that hypertext overviews have on the reader’s comprehension. In the present paper we have explored how hypertext overviews might affect comprehension with regard to (a) the time at which students read the overview and (b) the hypertext difficulty. The results from two eye-tracking studies revealed that reading a graphical overview at the beginning of the hypertext is related to an improvement in the participant’s comprehension of quite difficult hypertexts, whereas reading an overview at the end of the hypertext is linked to a decrease in the student’s comprehension of easier hypertexts. These findings are interpreted in light of the Assimilation Theory and the Active Processing model. Finally, the key educational and hypertext design implications of the results are discussed.     

Mature <Emphasis Type="Italic">versus</Emphasis> emerging technologies for CO<Subscript>2</Subscript> capture in power plants: Key open issues in post-combustion amine scrubbing and in chemical looping combustion

Carbon capture and storage (CCS) have acquired an increasing importance in the debate on global warming as a mean to decrease the environmental impact of energy conversion technologies, by capturing the CO₂ produced from the use of fossil fuels in electricity generation and industrial processes. In this respect, post-combustion systems have received great attention as a possible near-term CO₂ capture technology that can be retrofitted to existing power plants. This capture technology is, however, energy-intensive and results in large equipment sizes because of the large volumes of the flue gas to be treated. To cope with the demerits of other CCS technologies, the chemical looping combustion (CLC) process has been recently considered as a solution for CO₂ separation. It is typically referred to as a technology without energy penalty. Indeed, in CLC the fuel and the combustion air are never mixed and the gases from the oxidation of the fuel (i.e., CO₂ and H₂O) leave the system as a separate stream and can be separated by condensation of H₂O without any loss of energy. The key issue for the CLC process is to find a suitable oxygen carrier, which provides the fuel with the activated oxygen needed for combustion. The aim of this work is to explore the feasibility of using perovskites as oxygen carriers in CLC and to consider the possible advantages with respect to the scrubbing process with amines, a mature post-combustion technology for CO₂ separation.

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Unpicking PLAID: a cryptographic analysis of an ISO-standards-track authentication protocol

The Protocol for Lightweight Authentication of Identity (PLAID) aims at secure and private authentication between a smart card and a terminal. Originally developed by a unit of the Australian Department of Human Services for physical and logical access control, PLAID has now been standardized as an Australian standard AS-5185-2010 and is currently in the fast-track standardization process for ISO/IEC 25185-1. We present a cryptographic evaluation of PLAID. As well as reporting a number of undesirable cryptographic features of the protocol, we show that the privacy properties of PLAID are significantly weaker than claimed: using a variety of techniques, we can fingerprint and then later identify cards. These techniques involve a novel application of standard statistical and data analysis techniques in cryptography. We discuss potential countermeasures to our attacks and comment on our experiences with the standardization process of PLAID.     

Measuring offence-specific forgiveness in marriage: The Marital Offence-Specific Forgiveness Scale (MOFS).

Three studies involving 328 married couples were conducted to validate the Marital Offence-Specific Forgiveness Scale, a new measure assessing offence-specific forgiveness for marital transgressions. The studies examined the dimensionality; internal consistency; and discriminant, concurrent, and predictive validity of the new measure. The final scale comprised 2 distinct correlated dimensions, 1 positive (Benevolence) and 1 negative (Resentment–Avoidance), both of which had adequate internal consistency. The 2 dimensions discriminated marital forgiveness from affective empathy, rumination, attributions, and marital quality. Convergent validity of the new scale was indicated by significant relationships between its underlying dimensions and a host of predicted sociocognitive, relationship, trait, and well-being correlates of forgiveness. Providing evidence for predictive validity, forgiveness dimensions accounted for variability in relationship variables over a 6-month period. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High content of biogenic amines in Pecorino cheeses

Pecorino refers to Italian cheeses made exclusively from raw or pasteurized ewes' milk, characterized by a high content of fat matter and it is mainly produced in the Middle and South of Italy by traditional procedures. The autochthonous microbiota plays an important role in the organoleptic traits of Pecorino cheese and it can influence biogenic amines (BA) content.     

Toward a European Eco-label brand for residential buildings: Holistic or by-components approaches?

The Eco-label scheme is becoming ever more important in the environmental certification of products and services, especially in light of the recent ambitious aim of containing greenhouse emissions and improving the efficiency of utilizing energy sources. A recently introduced hypothesis concerns the European Eco-label scheme relating to buildings, in the awareness that the construction industry is of primary importance to the whole economic and social life of states. This scheme should adopt an integrated approach to environmental problems and include construction, day-to-day management, and the possible disposal of building materials, throughout the life cycle of the building. In addition, in consideration of the particular scope of buildings, the main aim of this new scheme should also be to ensure enhanced conditions of comfort to the occupants of these buildings. In sight of this challenge, the building can be regarded as a summation of components (each of them characterized by a given level of environmental quality) or as a unique physical entity aimed at delivering suitable indoor condition to occupants with an assigned amount of primary energy and with a limited impact on the natural environment. In the paper, both approaches will be investigated, keeping also in mind the initiatives that are currently on the ground in the aim of establishing ecological criteria for the award of the Community Eco-label for buildings.     

A Generalized Nash Equilibrium Model of Market Coupling in the European Power System

??Market Coupling?? is currently seen as the most advanced market design in the restructuring of the European electricity market. Market Coupling, by construction, introduces what is generally referred to as an incomplete market: it leaves several constraints out of the market and hence avoids pricing them. This may or may not have important consequences in practice depending on the case on hand. Quasi-Variational Inequality problems and the associated Generalized Nash Equilibrium can be used for representing incomplete markets. Recent papers propose methods for finding a set of solutions of Quasi-Variational Inequality problems. We apply one of these methods to a subproblem of market coupling namely the coordination of counter-trading. This problem is an illustration of a more general question encountered, for instance, in hierarchical planning in production management. We first discuss the economic interpretation of the Quasi-Variational Inequality problem. We then apply the algorithmic approach to a set of stylized case studies in order to illustrate the impact of different organizations of counter-trading. The paper emphasizes the structuring of the problem. A companion paper considers the full problem of Market Coupling and counter-trading and presents a more extensive numerical analysis.     

Meeting Interactivity Requirements in Mobile E-Witness: An Experimental Study

This paper describes the design and development of a session-layer load balancing mechanism and its deployment in a mobile surveillance system named Mobile E-Witness (MEW), which we have developed (Ghini et al., Multimedia Tools and Applications, 37(3), 293–318, 2008). The load balancing mechanism proposed in this paper allows MEW to effectively meet interactivity requirements and it is based on an “early retransmission” technique that exploits the overall bandwidth provided by a number of heterogeneous (broadband and metropolitan area) wireless adapters incorporated in MEW. This technique anticipates a suspected unavailability of the adapters in order to avoid the effects of network congestion and guarantee continuity of the communication service and support for multimedia services such as IP telephony. We have carried out an experimental evaluation of the MEW prototype in order to assess its effectiveness in meeting interactivity and responsiveness requirements. This paper summarizes our design and the principal results we have obtained from the evaluation mentioned above.     

Early use of PEPA dialyzer for light chains removal and for the recovery from myeloma cast nephropathy: A case report

Chemotherapy and extracorporeal treatment reduce serum free light chains (FLCs) allowing the recovery of acute kidney injury (AKI) caused by myeloma cast nephropathy (MCN). We report the first case of recovery from AKI in a patient with MCN who underwent the removal of FLCs using the PEPA filter, with an undisclosed cut‐off, combined with chemotherapy for multiple myeloma (MM).