Mortars: a complex material in cultural heritage. A multi-analytical procedure to characterize historical mortars.

This thesis deals with the identification of mortars composition in a cultural and historical context. In detail, the main concern was to collect information for proposing an analytical procedure able to define the mortar typology, balancing advantages, drawbacks, time and costs. In addition, several new techniques have been recently introduced in conservation science and the aim of this research is also to consider these new competences too. To understand the interactions between components of mortars, in Chapter 1 a general overview of the subject is given with a description of the materials and of the historical background, based on the review of the large bibliography taken into account. In Chapter 2 the methods used for the preparation of the model samples and the final composition are explained. Moreover, the analytical techniques used in this research (optical microscopy and petrographic analysis, powder X-ray diffraction, infrared spectroscopy, Raman spectroscopy, environmental scanning electron microscopy, thermal analysis, mercury intrusion porosimetry and computed tomography) are described, specifying the setting of the instruments. In Chapter 3 the results of the characterization of the raw materials and of the model samples are shown, the most meaningful results are shown for each technique. The discussion of the experimental data is presented in Chapter 4, and some analytical protocols are proposed, described and explained. In the last chapter, Chapter 5, the conclusions and the future development of this research are underlined

Mortars: a complex material in cultural heritage. A multi-analytical procedure to characterize historical mortars.

This thesis deals with the identification of mortars composition in a cultural and historical context. In detail, the main concern was to collect information for proposing an analytical procedure able to define the mortar typology, balancing advantages, drawbacks, time and costs. In addition, several new techniques have been recently introduced in conservation science and the aim of this research is also to consider these new competences too. To understand the interactions between components of mortars, in Chapter 1 a general overview of the subject is given with a description of the materials and of the historical background, based on the review of the large bibliography taken into account. In Chapter 2 the methods used for the preparation of the model samples and the final composition are explained. Moreover, the analytical techniques used in this research (optical microscopy and petrographic analysis, powder X-ray diffraction, infrared spectroscopy, Raman spectroscopy, environmental scanning electron microscopy, thermal analysis, mercury intrusion porosimetry and computed tomography) are described, specifying the setting of the instruments. In Chapter 3 the results of the characterization of the raw materials and of the model samples are shown, the most meaningful results are shown for each technique. The discussion of the experimental data is presented in Chapter 4, and some analytical protocols are proposed, described and explained. In the last chapter, Chapter 5, the conclusions and the future development of this research are underlined

Parvovirus B19 Infection and Severe Anemia in Renal Transplant Recipients

Kidney transplant (KT) recipients can develop symptomatic Parvovirus (PV) B19 infections, frequently associated with persistent anemia. The aim of this study was to evaluate the prevalence and clinical significance of PV B19 infection in anemic and non-anemic KT patients. Overall, out of 64 patients monitored for the presence of PV B19 by real-time PCR, 2 (3.12%) had an active PV B19 infection, in absence of other viral coinfections. The 2 cases occurred in nonanemic kidney transplant patients group (2/50, 4%), while none of the anemic transplant patients (0/14) was found to suffer from this infection. Moreover, patients affected by active PV B19 infection showed viral loads not exceeding 1 × 105 genome copies/reaction. In conclusion, in this study, PV B19 infection was not common in renal transplant population and wasn't associated with severe anemia

Ancient bread recipes: Archaeometric data on charred findings

This study examines charred bread-like samples found in several archaeological sites across northern Italy and dating from the Early Bronze Age to the Early Middle Ages, some of which are included amongst the UNESCO World Heritage Sites. The aim is to investigate differences and homogeneities in bread production processes in different eras and cultures. Bread was a staple food in many ancient societies, but has rarely been found amongst the materials that survive in archaeological sites. When it is found, it is usually because the bread was charred by accidental combustion (falling into the oven during baking) or deliberate combustion (for ritual purposes). The literature on the issue is not abundant, but has been growing over the past decade. There is, therefore, room to propose new study methodologies at this time. We studied eight samples of charred bread-like products and we used optical and scanning electron microscopy to identify plant tissue remains attributable to cereal caryopses, partly modified by bread-making processes. Energy dispersive X-ray spectroscopy and, for the first time, infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR) were also used to investigate the composition and preparation methods of the different types of bread-like products. In particular, FTIR-ATR analysis can give indications about the presence of starch, gluten and lignin in the sample under investigation and it can, therefore, be used as a screening to guide subsequent SEM analysis in the search for specific cereal residues in the dough. In some cases, the different techniques used also revealed the presence of minerals such as silicates and carbonates, probably due to grinding residues or poor sample cleaning. During SEM observations, phytoliths, diatoms and framboids were also found in some of the samples

Minimum number of myosin motors accounting for shortening velocity under zero load in skeletal muscle

KEY POINTS: Myosin filament mechanosensing determines the efficiency of the contraction by adapting the number of switched ON motors to the load. Accordingly, the unloaded shortening velocity (V (0)) is already set at the end of latency relaxation (LR), ∼10 ms after the start of stimulation, when the myosin filament is still in the OFF state. Here the number of actin‐attached motors per half‐myosin filament (n) during V (0) shortening imposed either at the end of LR or at the plateau of the isometric contraction is estimated from the relation between half‐sarcomere compliance and force during the force redevelopment after shortening. The value of n decreases progressively with shortening and, during V (0) shortening starting at the end of LR, is 1–4. Reduction of n is accounted for by a constant duty ratio of 0.05 and a parallel switching OFF of motors, explaining the very low rate of ATP utilization found during unloaded shortening. ABSTRACT: The maximum velocity at which a skeletal muscle can shorten (i.e. the velocity of sliding between the myosin filament and the actin filament under zero load, V (0)) is already set at the end of the latency relaxation (LR) preceding isometric force generation, ∼10 ms after the start of electrical stimulation in frog muscle fibres at 4°C. At this time, Ca(2+)‐induced activation of the actin filament is maximal, while the myosin filament is in the OFF state characterized by most of the myosin motors lying on helical tracks on the filament surface, making them unavailable for actin binding and ATP hydrolysis. Here, the number of actin‐attached motors per half‐thick filament during V (0) shortening (n) is estimated by imposing, on tetanized single fibres from Rana esculenta (at 4°C and sarcomere length 2.15 μm), small 4 kHz oscillations and determining the relation between half‐sarcomere (hs) compliance and force during the force development following V (0) shortening. When V (0) shortening is superimposed on the maximum isometric force T (0), n decreases progressively with the increase of shortening (range 30–80 nm per hs) and, when V (0) shortening is imposed at the end of LR, n can be as low as 1–4. Reduction of n is accounted for by a constant duty ratio of the myosin motor of ∼0.05 and a parallel switching OFF of the thick filament, providing an explanation for the very low rate of ATP utilization during extended V (0) shortening

Supernormal functional reserve of apical segments in elite soccer players: an ultrasound speckle tracking handgrip stress study

<p>Abstract</p> <p>Background</p> <p>Ultrasound speckle tracking from grey scale images allows the assessment of regional strain derived from 2D regardless of angle intonation, and it is highly reproducible. The study aimed to evaluate regional left ventricular functional reserve in elite soccer players.</p> <p>Methods</p> <p>50 subjects (25 elite athletes and 25 sedentary controls), aged 26 ± 3.5, were submitted to an echo exam, at rest and after the Hand Grip (HG) test. Both standard echo parameters and strain were evaluated.</p> <p>Results</p> <p>Ejection fraction was similar in athletes and controls both at rest (athletes 58 ± 2 vs controls 57 ± 4 p ns) and after HG (athletes 60 ± 2 vs controls 58 ± 3 p ns). Basal (septal and anterior) segments showed similar strain values in athletes and controls both at rest (athletes S% -19.9 ± 4.2; controls S% -18.8 ± 4.9 p = ns) and after HG (athletes S% -20.99 ± 2.8; controls S% -19.46 ± 4.4 p = ns). Medium-apical segments showed similar strain values at rest (athletes S% -17.31 ± 2.3; controls S% -20.00 ± 5.3 p = ns), but higher values in athletes after HG (athletes S% -24.47 ± 2.8; controls S% -20.47 ± 5.4 p < 0.05)</p> <p>Conclusion</p> <p>In athletes with physiological myocardial hypertrophy, a brief isometric effort produces enhancement of the strain in medium-apical left ventricular segments, suggesting the presence of a higher regional function reserve which can be elicited with an inotropic challenge and suitable methods of radial function quantification such as 2D-derived strain.</p

Information and Willingness to Pay in a Contingent Valuation Study: The Value of S. Erasmo in the Lagoon of Venice

This paper reports on a contingent valuation study eliciting willingness to pay for a public program for the preservation of lagoon, beach and infrastructure in the island of S. Erasmo in the Lagoon of Venice. A referendum dichotomous choice approach with a follow-up question is used to obtain information about willingness to pay from a sample of residents of the Veneto Region in Italy. We use split samples to investigate the effect of providing different levels of information to respondents before asking the payment questions. Our experimental treatment is a reminder of possible reasons for voting in favor or against the proposed program before the referendum question. We find that reminding respondents of the reasons for voting for or against the public works increases WTP among less highly educated respondents, and decreases WTP among more highly educated respondents

Order Flow and the Formation of Dealer Bids: An Analysis of Information and Strategic Behavior in the Government of Canada Securities Auctions

Using data on Government of Canada securities auctions, this paper shows that in countries where direct access to primary issuance is restricted to government securities dealers, Order-flow" information is a key source of private information for these security dealers. Order-flow information is revealed to a security dealer through his interactions with customers, who can place bids in the auctions only through the security dealer. Since each dealer interacts with a different set of customers, they, in effect, see different portions of the market demand and supply curves, leading to differing private inferences of where the equilibrium price might

Participation in and Compliance with Public Voluntary Environmental Programs: An Evolutionary Approach

The joint evolution of participating and complying firms in a public VA, along with the evolution of the pollution stock is examined. Replicator dynamics modeling participation and compliance are combined with pollution stock dynamics. Fast-slow selection dynamics are used to capture the fact that decisions to participate in and further comply with the public VA evolve in different time scales. Evolutionary stable (ES) equilibria depend on the structure of the legislation and auditing probability. Partial participation and partial compliance can be ES equilibria, with possible multiplicities, in addition to the monomorphic equilibria of full (non) compliance. Convergence to these equilibria could be monotonic or oscillating. Full participation and compliance can be attained if the regulator is pre-committed to certain legislation and inspection probabilities, or by appropriate choices of the legislatively set emission level and the non-compliance fine