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Numerical simulations are important tools for the assessment of exploiting geothermal energy in heat pump applications. They can be used to evaluate the performance of the system, the long-term production scenarios and the sustainability of the geothermal reservoir. The present work introduces and describes a numerical model, in which a dedicated Matlab script has been realized to allow sequentially coupled simulations of a shallow geothermal reservoir and of a heat pump system. A mathematical model of a dual-source heat pump, working alternatively with the ground or the air as heat source/sink, has been developed in Matlab environment. The heat exchangers of the heat pump have been modelled considering the equations that govern the physical phenomena. The dynamic numerical simulator FEFLOW, based on the finite element method, has been used to simulate the behaviour of the geothermal reservoir, subjected to heat extraction/reinjection by a closed loop vertical heat exchangers field. This methodological approach is useful to evaluate the performance of the coupled system in the long term, and it is important for understanding the advantages and limits of the dual-source heat pump in assuring sustainability over time avoiding the depletion of geothermal resources. The models and their coupling have been calibrated and validated with experimental data from a shallow geothermal plant located in Tribano (Padova, IT). It consists of eight coaxial borehole heat exchangers 30 m deep, connected to a 16 kW dual-source heat pump prototype. The heat pump system provides heating and cooling to an office area. The coupled model has been used to compare the performance of the heat pump when working in air-mode only or in ground-mode only. This allowed the development of a switching control strategy between the two thermal sources. Yearly simulations with the switching strategy have shown that the seasonal performance factor of the dual-source heat pump during the heating mode can be 13.8 % higher compared to the one obtained with a conventional air source heat pump and 3.8 % higher with respect to a ground source heat pump.

Arterial hypertension (AH) represents a major risk factor for cardiovascular disease and is associated to several complications, such as prolonged corrected QT (QTc) interval and impaired heart rate variability (HRV). Secondary causes of AH include autosomal dominant polycystic kidney disease (ADPKD) and atherosclerotic renal artery stenosis (ARAS), both known to be related to arrhythmic risk and autonomic imbalance. The aim of the study is to evaluate whether global autonomic activity and QTc interval differently affect ADPKD and ARAS hypertensive patients.An observational study was performed on 59 patients: 16 ADPKD patients and 19 diagnosed with ARAS, compared to 24 healthy controls (HC). All patients underwent clinical evaluation, biochemical lab tests, 24-hour electrocardiogram (ECG) and renal Doppler ultrasound. HRV was assessed through the analysis of 24-hour ECG to detect standard deviation of normal-to-normal RR intervals (SDNN). QTc interval was defined as prolonged when440 msec.SDNN was significantly lower in ADPKD and ARAS patients than HC (p0.0001) and no significant differences were found between ADPKD and ARAS patients (p0.05). QTc was found significantly higher in ARAS patients than HC (p = 0.001) and in ARAS patients than ADPKD patients (p = 0.004).The pathogenesis of hypertension in ADPKD and ARAS patients is related to the activation of the renin angiotensin aldosterone system (RAAS). In ADPKD, cyst enlargement leads to kidney ischemia and renin release, associated to endothelial dysfunction, low nitric oxide and sympathetic tone activation. Differently, reduction in renal perfusion pressure activates RAAS and renal adrenergic nerves in ARAS patients. We can speculate that prolonged QTc interval is more present in ARAS vs. ADPKD hypertensive patients due to a greater activation of RAAS. We suggest adding 24-hour HRV evaluation in association with traditional risk factors in course of ADPKD and ARAS hypertension to better stratify cardiovascular risk in these groups of patients.

The Mediterranean Large Elasmobranchs Monitoring (MEDLEM) database contains more than 3,000 records (with more than 4,000 individuals) of large elasmobranch species from 21 different countries around the Mediterranean and Black seas, observed from 1666 to 2017. The principal species included in the archive are the devil ray (1,868 individuals), the basking shark (935 individuals), the blue shark (622 individuals), and the great white shark (342 individuals). In the last decades, other species such as the thresher shark (187 individuals), the shortfin mako (180 individuals), and the spiny butterfly ray (138) were reported with increasing frequency. This was possibly due to increased public awareness on the conservation status of sharks, and the consequent development of new monitoring programs. MEDLEM does not have homogeneous reporting coverage throughout the Mediterranean and Black seas and it should be considered as a database of observed species presence. Scientific monitoring efforts in the south-eastern Mediterranean and Black seas are generally lower than in the northern sectors and the absence of some species in our database does not imply their actual absence in these regions. However, the available data allowed us to analyse the frequency and spatial distribution of records, the size frequencies for a few selected the available data allowed us to analyse the frequency and spatial distribution of records, the size frequencies for a few selected species, the overall area coverage, and which species are involved as bycatch by different fishing gears. © 2020 Mediterranean Marine Science.

37th European Photovoltaic Solar Energy Conference and Exhibition; 725-727, In this communication we report on the photovoltaic performances of PATTD, a donor polymer based on the novel anthradithiophene (AT) electron-rich unit and the electron-poor dithiophenedione (TD) unit, connected by two thiophene flanking units. Inverted solar cells with architecture glass/ITO/ZnO/PATTD:X/MoO3/Ag have been fabricated, using different acceptors (X), by typical laboratory-scale techniques, namely spincoating for the electron transport layer and the active layer and vacuum evaporation for the hole transport layer and the anode. Maximum power conversion efficiencies (PCEs) of 10.5% have been achieved with X=ITIC-4F as acceptor, while X=ITIC afforded devices with 8.6 % PCE. Notably, with X=PCBM, PCE values of 6.7% has been obtained, demonstrating that good performances can be obtained also with a relatively cheap acceptor. To prove the potential of this polymer in a roll-to-roll scalable process, the PATTD:ITIC blend was deposited on PET/ITO/ZnO by slot-die coating, leading to PCE values of 4.8% in a R2R system.

Purpose: Madagascar is worldwide recognized as one of the top biodiversity hotspots. Our purpose was to investigate a fungal species found in Madagascar as a sclerotial mass. Methods: A fungal sample consisting of a sclerotium was collected on a Raphia farinifera log in Antsohihy (North Madagascar) and sent to our lab for characterization. Morphological and molecular analyses were carried out and small pieces of sclerotium tissue were inoculated in agar in order to isolate mycelium. Results: light and scanning electron microscope observations of the sclerotium revealed a carpet of thick-walled hyphae whereas light microscope observations of mycelium showed nematode-trapping structures. The nrITS sequence obtained from the sclerotium was compared with the GeneBank database showing high similarity with Pleurotus tuber-regium. A phylogenetic analysis clearly revealed two clades in this species: one of mainly African origin, the other one of Asian and Australasian origin. Whether these two clades should be considered two subspecies of the same species or two distinct species, is questioned, discussed. Conclusion: This study reports the first molecular identification of Pleurotus tuber-regium from Madagascar., Annali di Botanica, Vol 9 (2019)