Andrea Loi

Flexible, organic, ion-sensitive field-effect transistor

Organic ion-sensitive field-effect transistors assembled on flexible plastic films have been fabricated. A thin Mylar™ foil acts both as substrate and gate dielectric. The active layer is vacuum-sublimed on one side of the foil, prepatterned with bottom-contact Au source and drain electrodes. The opposite side of the insulating film is in contact with an electrolytic solution that together with a reference electrode forms an ionic gate. A sensitivity of the device to the pH of the electrolyte solution has been observed. Thanks to the flexibility of the substrate and the low cost of the employed technology, this device opens the way for flexible sensors that can be employed in a variety of innovative applications.

The Tian-Yau-Zelditch asymptotic expansion for real analytic Kahler metrics

Let M be a compact Kahler manifold endowed with a real analytic and polarized Kahler metric g and let Tmω(x) be the corresponding Kempfs distortion function. In this paper we compute the coefficients of Tian–Yau–Zelditch asymptotic expansion of Tmω(x) using quantization techniques alternative to Lus computations in [10].

Berezin quantization of homogeneous bounded domains

We prove that a homogeneous bounded domain admits a Berezin quantization.

Kähler–Einstein submanifolds of the infinite dimensional projective space

This paper consists of two main results. In the first one we describe all Kähler immersions of a bounded symmetric domain into the infinite dimensional complex projective space in terms of the Wallach set of the domain. In the second one we exhibit an example of complete and non-homogeneous Kähler–Einstein metric with negative scalar curvature which admits a Kähler immersion into the infinite dimensional complex projective space.

Balanced metrics on Cartan and Cartan–Hartogs domains

This paper consists of two results dealing with balanced metrics (in Donaldson terminology) on noncompact complex manifolds. In the first one we describe all balanced metrics on Cartan domains. In the second one we show that the only Cartan–Hartogs domain which admits a balanced metric is the complex hyperbolic space. By combining these results with those obtained in Loi and Zedda (Mathematische Annalen, 2011, to appear) we also provide the first example of complete, Kähler-Einstein and projectively induced metric g such that αg is not balanced for all α > 0.

Effect of Beetroot Juice Supplementation on Aerobic Response during Swimming

The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO2), carbon dioxide production (VCO2), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol of NO3−). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.

Does sensorimotor training improve the static balance of young volleyball players

The aim of this investigation is to assess the effectiveness of a 6-week balance training (BT) protocol, integrated in regular training sessions, on postural sway of young female volleyball players (n = 26, age 13.0 ± 0.2 years) divided into two groups (intervention and control; 13 per group). Trials were performed for bipedal and unipedal stance conditions before and after the BT protocol, using a pressure platform to collect center-of-pressure (COP) time series that were processed to calculate sway area, COP path length, and maximum displacement range in anteroposterior and mediolateral directions. The intervention group exhibited smaller sway areas in eyes closed conditions (intervention = 42.76 mm2, control = 67.60 mm2; p < 0.05) and Romberg quotients (intervention = 1.11 mm, control = 1.82 mm) in bipedal stance, while all the other parameters were unaffected. BT also reduced sway area (intervention = 122.70 mm2, control = 187.18 mm2) and anteroposterior COP displacements (intervention = 20.18 mm, control = 22.38 mm) of the non-dominant limb for single-leg stance. No significant change was found for the dominant limb. Although it is possible to hypothesize a beneficial effect of BT on young athletes, further investigations are required to clarify its actual effect on balance performance with respect to normal volleyball training.

Assessment of the specificity of cardiopulmonary response during tethered swimming using a new snorkel device

This study aimed at comparing maximal oxygen uptake (VO2max), maximal heart rate (HRmax), and anaerobic threshold (AT) obtained from tethered swimming (SW) and three other testing procedures: cycling (CY), running (RU), and arm cranking (AC). Variables were assessed in 12 trained male swimmers by a portable gas analyzer connected to a modified snorkel system to allow expired gases collection during swimming. Athletes exhibited a higher VO2max during the SW test as compared to the CY and the AC tests. There was no significant difference in VO2max between the SW and the RU test, but the Bland and Altman plot highlighted a poor agreement between results. Moreover, AT occurred at higher workloads during SW in comparison to the other tests. These results do not support the use of any unspecific testing procedures to estimate VO2max, HRmax, and AT for swimming.

The diastatic exponential of a symmetric space

AbstractLet (M, g) be a real analytic Kähler manifold. We say that a smooth map Expp : W → M from a neighbourhood W of the origin of TpM into M is a diastatic exponential at p if it satisfies