Aerosol direct radiative effect in the Po Valley region derived from AERONET measurements

International audienceThe aerosol direct radiative effect (ADRE) affecting the Po Valley and the adjacent North Adriatic Sea is studied using 10-year series of measurements collected at two AERONET sites located in the western part of the Valley (Ispra), and on a platform (AAOT) offshore Venice. This region is characterized by a high, mostly continental, aerosol load with comparable average aerosol optical thickness ?a at both locations (0.21 at 500 nm) and more absorbing aerosols at Ispra. A dynamic aerosol model accounting for the changes in scattering phase function with ?a is used for radiative transfer calculations, together with boundary conditions representative of terrestrial and marine surfaces. A sensitivity analysis allows the construction of an error budget for the daily ADRE estimates, found to be of the order of 20% and mostly due to uncertainties on aerosol single scattering albedo and ?a. The daily radiative efficiencies, normalized by ?a at 500 nm, increase from December to June, from ?17 to ?24 W m?2 ?a?1 at top-of-atmosphere (TOA) and ?33 to ?72 W m?2 ?a?1 at surface for the Po Valley, and from ?15 to ?32 (TOA) and ?35 to ?65 W m?2 ?a?1 (surface) for the AAOT site. The average of log-transformed ADRE for TOA, surface and atmosphere are ?5.2, ?12.2 and +6.8 W m?2 for the Po Valley case, and ?6.5, ?13.0 and +6.5 W m?2 for the AAOT site but these values can be much higher for individual days. Concurrent clear-sky days give indications on the regional atmospheric heating spatial gradients. Differences between the atmospheric ADRE at the two locations average 6.3 W m?2 with a gradient positive towards the inner valley in 65% of the cases. This study confirms the importance of duly considering the radiative impact of aerosols on the regional climate

Experimental characterization of lithium-ion cell strain using laser sensors

The characterization of thickness change during operation of LFP/Graphite prismatic batteries is presented in this work. In this regard, current rate dependence, hysteresis behaviour between charge and discharge and correlation with phase changes are deepened. Experimental tests are carried out with a battery testing equipment correlated with optical laser sensors to evaluate swelling. Furthermore, thickness change is computed analytically with a mathematical model based on lattice parameters of the crystal structures of active materials. The results of the model are validated with experimental data. Thickness change is able to capture variations of the internal structure of the battery, referred to as phase change, characteristic of a certain state of charge. Furthermore, phase change shift is a characteristic of battery ageing. Being able to capture these properties with sensors mounted on the external surface the cell is a key feature for improving state of charge and state of health estimation in battery management system

Phase-Insensitive Scattering of Terahertz Radiation

The nonlinear interaction between Near-Infrared (NIR) and Terahertz pulses is principally investigated as a means for the detection of radiation in the hardly accessible THz spectral region. Most studies have targeted second-order nonlinear processes, given their higher efficiencies, and only a limited number have addressed third-order nonlinear interactions, mainly investigating four-wave mixing in air for broadband THz detection. We have studied the nonlinear interaction between THz and NIR pulses in solid-state media (specifically diamond), and we show how the former can be frequency-shifted up to UV frequencies by the scattering from the nonlinear polarisation induced by the latter. Such UV emission differs from the well-known electric-field-induced second harmonic (EFISH) one, as it is generated via a phase-insensitive scattering, rather than a sum- or difference-frequency four-wave-mixing process

Synthesis, Conformation and Antiproliferative Activity of Isothiazoloisoxazole 1,1-dioxides

Sixteen new isothiazoloisoxazole 1,1-dioxides, one new isothiazolotriazole and one new isothiazolopyrazole have been synthesised by using 1,3-dipolar cycloadditions to isothiazole 1,1-dioxides. One sub-set of these isothiazoloisoxazoles showed low μM activity against a human breast carcinoma cell line, whilst a second sub-set plus the isothiazolotriazole demonstrated an interesting restricted rotation of sterically hindered bridgehead substituents. A thiazete 1,1-dioxide produced from one of the isothiazole 1,1-dioxides underwent conversion into an unknown 1,2,3-oxathiazolin-2-oxide upon treatment with Lewis acids, but was inert towards 1,3-dipoles and cyclopropenones. Six supporting crystal structures are included

Laser-assisted guiding of electric discharges around objects

Electric breakdown in air occurs for electric fields exceeding 34 kV/cm and results in a large current surge that propagates along unpredictable trajectories. Guiding such currents across specific paths in a controllable manner could allow protection against lightning strikes and high-voltage capacitor discharges. Such capabilities can be used for delivering charge to specific targets, for electronic jamming, or for applications associated with electric welding and machining. We show that judiciously shaped laser radiation can be effectively used to manipulate the discharge along a complex path and to produce electric discharges that unfold along a predefined trajectory. Remarkably, such laser-induced arcing can even circumvent an object that completely occludes the line of sight

Reply to Comment on: Hawking radiation from ultrashort laser pulse filaments

A comment by R. Schutzhold et al. raises possible concerns and questions regarding recent measurements of analogue Hawking radiation. We briefly reply to the opinions expressed in the comment and sustain that the origin of the radiation may be understood in terms of Hawking emission

Robot therapy for functional recovery of the upper limbs: a pilot study on patients after stroke.

Objective: To verify the possibility of administering robotaided therapy for the upper limbs in patients after stroke; to evaluate patients' degree of acceptance and compliance with the treatment; to establish if the treatment has an effect on motor impairment and functional outcome. Design: Quasi-experimental, uncontrolled study. Subjects: Fourteen patients with chronic hemiparesis after stroke. Methods: Patients were treated with a robotic system for the upper limbs (ReoGo TM ; Motorika Medical Ltd, Israel). Subjects performed the following assessment, at the start (T0), at the end of treatment (T1), and at the follow-up performed one month after the end of treatment (T2): Fugl-Meyer test (FM) for upper limbs; strength evaluation; Ashworth scale; visual analogue scale (VAS) for pain; Frenchay Arm test (FAT); Box and Block test (BB Functional Independence Measure (FIM TM ); ABILHAND Questionnaire; Timed Up and Go test (TUG); Euro-Quality of Life questionnaire and; a VAS for treatment satisfaction were administered to the subjects. Results: Total scores of FM, B&B, FAT and FIM TM showed a statistically significant improvement from T0 and T1 (FM p < 0.002, B&B p < 0.012, FAT p < 0.023, FIM TM p < 0.007) and from T0 and T2 (FM p < 0.003, B&B p < 0.011, FAT p < 0.024, FIM p < 0.027). No statistically significant differences were found between evaluations at T1 and T2 (FM p < 0.595, B&B p < 0.491, FAT p < 0.317, FIM p < 0.180). Conclusion: The sample was capable of completing the treatment and demonstrated good participant satisfaction. This pilot study led to the finding of a clinical improvement and excellent patient compliance. It can be hypothesized that the results are robot-dependent and that they were learned and then maintained. However, the study is limited in that a control group was not used. As such, it is desirable to continue this study with a control group, as well as by designing a prospective longitudinal randomized controlled trial study

Identification of the first enantiopure Rac1&#8211;Tiam1 protein&#8211;protein interaction inhibitor and its optimized synthesis via phosphine free remote group directed hydroarylation

A phospine free hydroarylation reaction applied to norbornene derivatives is described for the first time and was exploited for the regioselective gram scale synthesis of AR-148, a known Rac1\u2013Tiam1 PPI inhibitor. Umpolung conversion of the nitro group into free amine allowed the regiocontrol of the key arylation step via a long range effect. The effect of AR-148 in comparison with its enantiomers on Rac1 activation of has been evaluated and ( 12)AR-148 has been identified as the first enantiomerically pure inhibitor of Rac1\u2013Tiam1 PPI

Spatiotemporal Amplitude and Phase Retrieval of Bessel-X pulses using a Hartmann-Shack Sensor

We propose a new experimental technique, which allows for a complete characterization of ultrashort optical pulses both in space and in time. Combining the well-known Frequency-Resolved-Optical-Gating technique for the retrieval of the temporal profile of the pulse with a measurement of the near-field made with an Hartmann-Shack sensor, we are able to retrieve the spatiotemporal amplitude and phase profile of a Bessel-X pulse. By following the pulse evolution along the propagation direction we highlight the superluminal propagation of the pulse peak