Novel insight into bronze disease gained by synchrotron-based photoelectron spectro-microscopy,in support of electrochemical treatment strategies

A recent assessment (Giovannelli, G., D'Urzo, L., Maggiulli, G., Natali, S., Pagliara, C., Sgura, I. & Bozzini, B. 2010. Journal of Solid State Electrochemistry, 14: 479–94.) of the corrosion state of a late Bronze Age artefact (ca. 1100 BCE) exposed to a coastal environment, based on optical and scanning electron microscopies, X-ray fluorescence mapping, and X-ray diffractometry, led to recognition of bronze disease conditions essentially related to the presence of nantokite locked inside mesoscopic subsurface pits. The object was then treated successfully with a novel electrochemical approach specifically designed to allow penetration of the electric field into deep, screened pits. In order to further develop and optimize this promising approach by fine-tuning the capabilities of electrochemical control, more insight is required on the specific morphochemistry of the corrosion product scenario. To this end, here we report a space-dependent compositional and chemical-state analysis, performed with synchrotron-based scanning photoelectron microspectroscopy. The investigated object consists of a segregated cast bronze. The prevailing corrosion form is preferential attack of Sn-rich phases, accompanied by a synergistic type of Sn and Cu attack triggered by the peculiar type of decuprification taking place in a bronze disease framework and characterized by the formation of Sn(OH)Cl as a result of local HCl generation in the Cu corrosion process.     

Insect-Infested Wood Remediation by Microwave Heating and Its Effects on Wood Dehydration: A Case Study of Hylotrupes bajulus Larva

Wood artefacts are subject to damage by biologic infestations due to bacteria, insects, and fungal species. One of the worst feared attacks is due to the xylophagous insects whose larvae feed on wood by boring galleries, at the expense of building timbers and worked woods. These beetles are responsible for daily destruction of the world’s wooden cultural heritage, and their elimination has been always a big problem for conservation of wood. The need to avoid the use of chemical methods in conservation for pest control has led to the development of various non-chemical, non-toxic treatments. Among these, heating with microwaves (MW) seems to be one of the most promising, since it has already shown its high efficacy in destroying pests. Insect-infested wood remediation by MW heating in conservation is based on the larger thermal increment induced in larvae than in wood, due to their different dielectric permittivity in the GHz frequency range. However, the side effects that may occur due to MW heating of wood, such as dehydration, have never been discussed so far. Here we study the possible application of microwave heating as a remediation method for wood samples infested by the larvae of the insect Hylotrupes bajulus. We show that it is possible to set up exposure conditions able to achieve 100% of larvae death and that are sufficiently mild not to induce significant dehydration of the exposed wood from which shrinkage effects may derive. Indeed, under these conditions, MW-induced wood dehydration on cubic and parallelepiped sweetgum samples can be kept under control and to percentages as low as 0.4% (w/w).     

Reliability based multiobjective optimization for design of structures subject to random vibrations

Based on a multiobjective approach whose objective function （OF） vector collects stochastic reliability performance and structural cost indices, a structural optimization criterion for mechanical systems subject to random vibrations is presented for supporting engineer＇s design. This criterion differs from the most commonly used conventional optimum design criterion for random vibrating structure, which is based on minimizing displacement or acceleration variance of main structure responses, without considering explicitly required performances against failure. The proposed criterion can properly take into account the design-reliability required performances, and it becomes a more efficient support for structural engineering decision making. The multiobjective optimum （MOO） design of a tuned mass damper （TMD） has been developed in a typical seismic design problem, to control structural vibration induced on a multi-storey building structure excited by nonstationary base acceleration random process A numerical example for a three-storey building is developed and a sensitivity analysis is carried out. The results are shown in a useful manner for TMD design decision support.     

Unusual coin from the Parabita hoard: combined use of surface and micro-analytical techniques for its characterisation

Out of the staters collection of the National Archaeological Museum of Taranto, during the full examination of about one hundred coins minted by the Greek colony of Taras between the V century BC and the III century BC, our attention has been devoted to a lead coin, which has been regarded for many years as a genuine silver coin. This artifact, entry number 13 in the inventory list for the Parabita hoard, has been studied with the combined use of surface and micro-analytical techniques (SEM, EDX, PIXE, XRD). The joint use of different analytical techniques allowed us to obtain information about the morphology, the structure and the chemical composition of the analysed coin, that revealed a lead core coated with a bi-layer of copper and silver.     

CLAIRE: A combinatorial visual analytics system for information retrieval evaluation

Information Retrieval (IR) develops complex systems, constituted of several components, which aim at returning and optimally ranking the most relevant documents in response to user queries. In this context, experimental evaluation plays a central role, since it allows for measuring IR systems effectiveness, increasing the understanding of their functioning, and better directing the efforts for improving them. Current evaluation methodologies are limited by two major factors: (i) IR systems are evaluated as “black boxes”, since it is not possible to decompose the contributions of the different components, e.g., stop lists, stemmers, and IR models; (ii) given that it is not possible to predict the effectiveness of an IR system, both academia and industry need to explore huge numbers of systems, originated by large combinatorial compositions of their components, to understand how they perform and how these components interact together.We propose a Combinatorial visuaL Analytics system for Information Retrieval Evaluation (CLAIRE) which allows for exploring and making sense of the performances of a large amount of IR systems, in order to quickly and intuitively grasp which system configurations are preferred, what are the contributions of the different components and how these components interact together.The CLAIRE system is then validated against use cases based on several test collections using a wide set of systems, generated by a combinatorial composition of several off-the-shelf components, representing the most common denominator almost always present in English IR systems. In particular, we validate the findings enabled by CLAIRE with respect to consolidated deep statistical analyses and we show that the CLAIRE system allows the generation of new insights, which were not detectable with traditional approaches.     

The value of neurosurgical and intraoperative magnetic resonance imaging and diffusion tensor imaging tractography in clinically integrated neuroanatomy modules: A cross‐sectional study

Neuroanatomy is considered to be one of the most difficult anatomical subjects for students. To provide motivation and improve learning outcomes in this area, clinical cases and neurosurgical images from diffusion tensor imaging (DTI) tractographies produced using an intraoperative magnetic resonance imaging apparatus (MRI/DTI) were presented and discussed during integrated second‐year neuroanatomy, neuroradiology, and neurosurgery lectures over the 2008–2011 period. Anonymous questionnaires, evaluated according to the Likert scale, demonstrated that students appreciated this teaching procedure. Academic performance (examination grades for neuroanatomy) of the students who attended all integrated lectures of neuroanatomy, was slightly though significantly higher compared to that of students who attended these lectures only occasionally or not at all (P=0.04). Significantly better results were obtained during the national progress test (focusing on morphology) by students who attended the MRI/DTI‐assisted lectures, compared to those who did so only in part or not at all, compared to the average student participating in the national test. These results were obtained by students attending the second, third and, in particular, the fourth year (P≤0.0001) courses during the three academic years mentioned earlier. This integrated neuroanatomy model can positively direct students in the direction of their future professional careers without any extra expense to the university. In conclusion, interactive learning tools, such as lectures integrated with intraoperative MRI/DTI images, motivate students to study and enhance their neuroanatomy education. Anat Sci Educ 6: 294–306. © 2013 American Association of Anatomists.     

Assessment of aerobic endurance: a comparison between CD-ROM and laboratory-based instruction

Traditional approaches to teaching exercise physiology are costly in terms of staff time and consumable expenses. Ethical considerations, large student numbers and availability of technical expertise magnify the delivery problems. In an attempt to overcome these problems, a CD-ROM version of a basic course in exercise physiology was designed and delivered to a group of undergraduate sport and exercise science students. It simulated five tests of aerobic endurance which are traditionally taught using laboratory methods. A controlled experiment was conducted to compare the two delivery methods, as part of an independent, formative evaluation. Although there were equal knowledge gains and the CD-ROM design and content were well rated by students who used it, this approach has engendered less student interaction, commitment to wider reading and in-depth understanding. Tutorials and other approaches designed to promote more active learning are now being introduced to accompany the use of the CD-ROM.     

Biological constraints on literacy acquisition

This paper investigates some of the biological constraints that shape the process of literacy acquisition. It explores the possibility of isolating processing components of reading which correspond to computational units of equivalent size in the neural architecture. After reviewing and evaluating the current approaches to the biology of literacy acquisition, the paper considers three interconnected topics: (a) developmental dissociations, (b) early stages of literacy acquisition (in a transparent orthography), and (c) effects of remedial intervention for children with reading disorders. Developmental dissociations between reading and severe mental retardation, motor impairment, congenital anarthria and inaccuracy in phonemic awareness tasks reveal the functional independence of the reading processes. The early stages of literacy acquisition in a transparent orthography show a very steep increase in word and non-word reading accuracy; a speed that could hardly be accounted for by unconstrained learning. Finally, rehabilitation treatments of reading disorders either produce no specific effects, or marginal improvements in reading accuracy, which fade away in the long term. Concurrently, these data suggest that the process of literacy acquisition is largely constrained by a specific biological architecture which mimics the functional properties of a modular system. It is speculated that the core component of reading is a metaphonological parser, designed to perform automatic cross-modal associations between visual and sublexical units, according to the paradigms set up by any orthographic system. The phylogenetic implications of the specificity hypothesis are discussed.     

Pulling and Pushing Forces for ICT Use in Initial Teacher Preparation for Secondary Schools

The transformative use of ICT （information and communication technology） in the educational setting is demanding continually assessing bottlenecks and conducive conditions with the aim of consolidating the pre-conditions and to dry the drawbacks from their root. As a result, this qualitative research approach employed to explore enablers and barriers of using ICT in initial teacher preparation in the context of JU （Jimma University）, Ethiopia. The study employed in-depth interviews with student teachers and teacher educators. Participants＇ perception of ICT as a vehicle for quality learning and multiple access to ICT use pointed as supportive conditions. Whereas, mismatch of methodologies being used in teacher education and schools, resource constraints, marginalizing teacher education program, unsuccessful experience of learning via ICT, and lack of clear directive and expertise on the use of ICT were some of the major issues forwarded by the participants. Redesigning of the teacher education program in the way of using ICT is clearly indicated, the system that forces and reinforces the use of ICT in place is among the recommendations forwarded.     

Cardiac indexes, cardiac damage biomarkers and energy expenditure in professional cyclists during the Giro d'Italia 3-weeks stage race

Introduction

The study of cardiac response to strenuous and continuous exercise is crucial to understanding the physiology of endurance. N-terminal proB-type natriuretic peptide (NT-proBNP) is a potential marker for monitoring myocardial wall stress, and troponins (TnT and TnI) are widely used in the diagnosis of cardiac ischemia and infarction. Strenuous exercise may generate transitory ischemia, myocardial stress, and diastolic left ventricular dysfunction, inducing the increased production of both these biomarkers. We measured changes in NT-proBNP and TnT in elite cyclists during a 3-week stage race, a model of strenuous exercise.

Materials and methods:

The study population was 9 professional cyclists participating in the 2011 Giro d’Italia. Pre-analytical and analytical phases scrupulously followed official recommendations. Anthropometric data, net energy expenditure and cardiac indexes (rate, diastolic and systolic blood pressure) were recorded. Blood samples were drawn pre-race (day −1) and at days 12 and 22; NT-proBNP and highly sensitive-troponin (Hs-TnT) concentrations were assayed and corrected for plasma volume changes.

Results:

Body-mass index decreased and energy expenditure increased by 52% during the race. NT-proBNP concentrations increased [day −1: 23.52 ng/L (9.67–34.33); day 12: 63.46 ng/L (22.15–93.31); P = 0.039; day 22: 89.26 ng/L (34.66–129.78) vs. day −1; P < 0.001] and correlated with heart rate (r = −0.51; P = 0.006), systolic pressure (r = 0.39; P = 0.046) and energy expenditure (r = 0.70; P < 0.001). TnT concentrations did not vary, but a widened TnT amplitude distribution was observed.

Conclusions:

Increases in NT-proBNP correlated with higher energy expenditure over a 3-week cycling stage race, possibly indicating myocardial stress.