A Proposal for New Microclimate Indexes for the Evaluation of Indoor Air Quality in Museums

A correct artwork preservation requires strict values of several microclimate parameters, in particular temperature, humidity, and light. In existing museums, the evaluation of the effectiveness of current building plant systems and management is essential to avoid artwork deterioration. In this work, we propose the use of five simple performance indexes that use monitored data to estimate the suitability of the whole museum system in the maintenance of benchmark values of temperature, humidity, and light. The new indexes also take into account microclimate daily span and spatial homogeneity, which can represent a criticality in the preservative process. We apply these new indexes to the results of a monitoring campaign in Palazzo Blu, a museum in Pisa, which lasted for almost four months during a temporary exhibition on Toulouse-Lautrec works. The indexes show a mainly acceptable instantaneous microclimate, but HVAC (Heating, Ventilating and Air Conditioning) system improvement is necessary to avoid high thermo-hygrometric daily span. This methodology is useful for the identification of microclimate criticalities and can help the cooperation between conservation experts and professionals giving hints to improve museum internal microclimate. In case ofalready optimal microclimate, these indexes can be useful in more complex analyses, including simulations of possible retrofit actions, keeping microclimate suitability as a constraint

Control of natural circulation loops by electrohydrodynamic pumping

The paper analyses the effect of electrohydrodynamic (EHD) pumping on the control of natural circulation loops (NCLs). The two major objectives of the investigation are: finding the optimal configuration of an EHD pump and demonstrating that the NCL flow direction can be inverted by exploiting the EHD phenomena. In the initial experimental set-up, we measured the static pressure rise given by an EHD pump made of three consecutive modules of point-ring electrodes for different dielectric fluids and electrode materials. When reversing the polarity of the applied DC voltage, we observed opposite pumping directions, suggesting the presence of two distinct EHD phenomena, inducing motion on opposite directions: ion-drag pumping and conduction pumping. The former was identified as a more efficient process compared to the latter. Based on these preliminary experiments, we built a NCL, operating with the fluid HFE-7100. Two oppositely mounted optimised pumping sections could be alternately activated, to promote clockwise or anticlockwise motion. In the first series of tests, alternately, the pumping sections were triggered prior to the heat input. In any case, the circulation followed the EHD pumping direction. In other tests, the electric field was applied when natural circulation was already present and the flow was reversed by means of opposite EHD pumping, at both polarities. Simply inverting the polarity of the applied voltage, we could alternate ion-drag and conduction pumping; in this way, we easily controlled the direction of motion by means of a single EHD pumping device

On Sustainable and Efficient Design of Ground-Source Heat Pump Systems

This paper is mainly aimed at stressing some fundamental features of the GSHP design and is based on a broad research we are performing at the University of Pisa. In particular, we focus the discussion on an environmentally sustainable approach, based on performance optimization during the entire operational life. The proposed methodology aims at investigating design and management strategies to find the optimal level of exploitation of the ground source and refer to other technical means to cover the remaining energy requirements and modulate the power peaks. The method is holistic, considering the system as a whole, rather than focusing only on some components, usually considered as the most important ones. Each subsystem is modeled and coupled to the others in a full set of equations, which is used within an optimization routine to reproduce the operative performances of the overall GSHP system. As a matter of fact, the recommended methodology is a 4-in-1 activity, including sizing of components, lifecycle performance evaluation, optimization process, and feasibility analysis. The paper reviews also some previous works concerning possible applications of the proposed methodology. In conclusion, we describe undergoing research activities and objectives of future works

Validation of SEAS, a Quasi-Steady-State Tool for Building Energy Audits

SEAS is an energy auditing software that can simulate residential, office, school, and hospital buildings, providing energy requirements for heating, domestic hot water production, ventilation, lighting, and other electrical uses. In order to validate this quasi-steady-state tool, we simulated in SEAS several reference cases (based on EN 15265 benchmark room) and a residential dwelling. We also used the dynamic simulation software TRNSYS and compared the results of the two software in terms of seasonal energy requirements for space heating and energy fluxes through the elements of the building envelope. Most of SEAS results are in good agreement with EN 15265 and with TRNSYS. Nonetheless, we pointed out that SEAS lacks in accuracy when it simulates high thermal inertia buildings with intermittent heating: for these particular cases, new correlations for dynamic parameters and reduction factors should be developed

Laparoscopia vs. laparotomia nelle resezioni per cancro colorettale. Metanalisi dei principali trial

The objective of this study is in the critical analysis of the results of the lap and open surgery in the colorectal carcinoma, through the meta-analysis of the principal trials. Patients and methods. A systematic search of the comparative studies has been made among lap and open surgery in the colorectal carcinoma, using PubMed and Cochrane Library. Among these, have been selected perspective studies containing the description of the surgical techniques, the perioperative results and the oncological long term results. Statistic analysis has been performed with the program NCSS (Kaysville 2006, Utah). Results. From the revision of the literature, 7 perspective studies have checked fit to a meta-analysis, for a total of 3580 patients. Among the operative outcomes, has been observed, with statistically significant, a reduction of the blood loss and of the morbidity, an earlier resumption to passing flatus and to normal diet, a reduction of the postoperative hospitalization for the lap; shorter operative time is releaved for the open surgery. Statistically significant differences have emerged neither on the other surgical outcomes (included mortality) nor on relapset of illness (regional or metastasis), crab-correlated mortality, long term survival. Conclusions. The laparoscopic can be considered a valid alternative to the traditional open surgery in the therapy of the colorectal carcinoma: the advantages consist in smaller trauma and reduction of morbidity and postoperative stay. The oncological results are the same of the open surgery

Building Energy Simulation by an In-House Full Transient Model for Radiant Systems Coupled to a Modulating Heat Pump

Radiant heating coupled to a heat pump is a particularly energy-efficient system, recommended in new constructions. However, the potential energy savings associated with this high thermal inertia system can only be achieved with appropriate control laws, to be tested in a full building–plant simulation environment. The developed transient code concurrently solves three tailored dynamic models of each involved sub-system, namely: building envelope (a benchmark room defined by ISO 13791), radiant floor (designed in accordance with EN 1264-2), and heat pump (an air-to-water electrically-driven modulating unit). Different control strategies were implemented, such as variation of internal temperature set-point dead band, supply temperature to radiant panels, and heating modes. Among the examined variables, we found that the higher energy savings (up to 15%) can be obtained by a proper choice of the supply temperature: in particular, fixed supply temperature should be preferred to climate-based control for this case study. The developed model can be used for optimal design of new systems and associated controls and for accurate energy audits of existing buildings employing these technological solutions

Can patients with epilepsy become bone marrow donors? A case report of allogeneic hematopoietic stem transplantation from child with seizures

Hematopoietic stem cell (HSC) transplantation is an important treatment option for malignant and non-malignant hematopoietic disorder in adults and children. For long time epilepsy was temporary exclusion condition to voluntary donation, and donors had to be medication or seizure free. It is still unclear if people with history of epilepsy are indeed potential eligible donors, even if a significant increased risk of adverse events in these donors has not been demonstrated. We studied a 10-year-old boy with symptomatic focal epilepsy who was the only available donor for his monozycote twin, suffering from acute lymphoblastic leukemia. A total of 3.39 x 108/kg HSCs were collected and reinfused to the leukemic brother after conditioning treatment. At the end of follow-up, our epilepsy patient had no consequences and his brother is in complete remission of the disease at 3 years from the transplant procedure. Our observation confirms that a patient with epilepsy can be a donor, without consequences for himself and for the recipient

Energy and geotechnical behaviour of energy piles for different design solutions

Energy piles are heat capacity systems that have been increasingly exploited to provide both supplies of energy and structural support to civil structures. The energy and geotechnical behaviours of such foundations, which are governed by their response to thermo-mechanical loads, is currently not fully understood, especially considering the different design solutions for ground-coupled heat exchangers. This paper summarises the results of numerical sensitivity analyses that were performed to investigate the thermo-mechanical response of a full-scale energy pile for different (i) pipe configurations, (ii) foundation aspect ratios, (iii) mass flow rates of the fluid circulating in the pipes and (iv) fluid mixture compositions. This study outlines the impacts of the different solutions on the energy and geotechnical behaviour of the energy piles along with important forethoughts that engineers might consider in the design of such foundations. It was observed that the pipe configuration strongly influenced both the energy and the geotechnical performance of the energy piles. The foundation aspect ratio also played an important role in this context. The mass flow rate of the fluid circulating in the pipes remarkably influenced only the energy performance of the foundation. Usual mixtures of a water-antifreeze liquid circulating in the pipes did not markedly affect both the energy and the geotechnical performance of the pile

Population and dynamical state of the eta Chamaeleontis sparse young open cluster

We report new results in our continuing study of the unique compact (1 pc extent), nearby (d = 97 pc), young (t = 9 Myr) stellar cluster dominated by the B9 star eta Chamaeleontis. An optical photometric survey spanning 1.3 x 1.3 pc adds two M5-M5.5 weak-lined T Tauri (WTT) stars to the cluster inventory which is likely to be significantly complete for primaries with masses > 0.15 M_sun. The cluster now consists of 17 primaries and approximately 9 secondaries lying within 100 AU of their primaries. The apparent distribution of 9:7:1 single:binary:triple systems shows 2-4 x higher multiplicity than in the field main sequence stars, and is comparable to that seen in other pre-main sequence (PMS) populations. The initial mass function (IMF) is consistent with that of rich young clusters and field stars. By extending the cluster IMF to lower masses, we predict 10-14 additional low mass stars with 0.08 < M < 0.15 M-sun and 10-15 brown dwarfs with 0.025 < M < 0.08 M_sun remain to be discovered. The eta Cha cluster extends the established stellar density and richness relationship for young open clusters. The radial distribution of stars is consistent with an isothermal sphere, but mass segregation is present with > 50 percent of the stellar mass residing in the inner 6 arcmin (0.17 pc). Considering that the eta Cha cluster is sparse, diffuse and young, the cluster may be an ideal laboratory for distinguishing between mass segregation that is primordial in nature, or arising from dynamical interaction processes.Comment: 10 pages, 7 figures, 2 tables, accepted for MNRA