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International audience; For broadband quantum noise reduction of gravitational-wave detectors, a frequency-dependent squeezed vacuum field realized using a filter cavity is the most promising technique and will be implemented in Advanced LIGO and Advanced Virgo in the fourth observing run. To obtain the benefit of frequency-dependent squeezing, the length and alignment of the filter cavity with respect to the squeezed vacuum field must be accurately controlled. To this purpose, a new length and alignment control scheme for a filter cavity, using coherent control sidebands, was suggested [Phys. Rev. D 102, 042003 (2020)]. The coherent control sidebands are already used to control the squeezing angle in squeezed vacuum sources for gravitational-wave detectors. As both the squeezed vacuum field and coherent control sidebands have the same mode-matching conditions and almost the same frequency, the length and alignment of the filter cavity with respect to the squeezed vacuum field can be accurately controlled with this scheme. In this paper, we experimentally demonstrate the new control scheme for a filter cavity with coherent control sidebands. In addition to the conventional filter cavity control with the green field, we succeed in controlling the length of a 300-m filter cavity with coherent control sidebands and reduce the filter cavity length noise (rms) from 6.8 to 2.1 pm.

In high-sensitive laser interferometers, such as the gravitational-wave detector KAGRA, ultra-high quality mirrors are essential. In the case of KAGRA, where cavity-mirrors are cooled down to 20 K, we are using large-size Sapphire crystals as the substrate for the main mirrors to achieve both a good optical quality (i.e., low absorption and uniform refractive index) and optimized thermal behavior under cryogenic temperatures. In order to characterize refractive-index inhomogeneities of large-size uniaxial samples such as the KAGRA Sapphire test-masses, we developed a dedicated setup, allowing to resolve birefringence changes with a sensitivity in the order of ∆n ≈ 10 −10 and a spatial resolution of 0.3 × 0.3 mm 2. In this paper, we will further show how we could draw information of internal stress distributions from the measured birefringence and present for the first time measurements on a KAGRA-sized Sapphire substrate which has been characterized in terms of absorption already in an earlier work. Both birefringence inhomogeneities and absorption distributions will be compared and correlations discussed.

Frequency dependent squeezing is the main upgrade for achieving broadband quantum noise reduction in upcoming observation runs of gravitational wave detectors. The proper frequency dependence of the squeezed quadrature is obtained by reflecting squeezed vacuum from a Fabry-Perot filter cavity detuned by half of its linewidth. However, since the squeezed vacuum contains no classical amplitude, co-propagating auxiliary control beams are required to achieve the filter cavity's length, alignment, and incident beam pointing stability. In our frequency dependent squeezing experiment at the National Astronomical Observatory of Japan, we used a control beam at a harmonic of squeezed vacuum wavelength and found visible detuning variation related to the suspended mirrors angular drift. These variations can degrade interferometer quantum noise reduction. We investigated various mechanisms that can cause the filter cavity detuning variation. The detuning drift is found to be mitigated sufficiently by fixing the incident beam pointing and applying filter cavity automatic alignment. It was also found that there is an optimal position of the beam on the filter cavity mirror that helps to reduce the detuning fluctuations. Here we report a stabilized filter cavity detuning variation of less than 10$\,$Hz compared to the 113$\,$Hz cavity linewidth. Compared to previously published results [Phys. Rev. Lett. 124, 171101 (2020)], such detuning stability would be sufficient to make filter cavity detuning drift induced gravitational wave detector detection range fluctuation reduce from $11\%$ to within $2\%$., Comment: Accepted by PRD

In developing countries, energy is recognized to be essential for promoting equitable growth, fostering social inclusion and preserving the environment. Nevertheless, the current state of the energy sectors of developing countries still represents a major hindrance to the fulfillment of this goal. In this frame, electrical energy storage may allow a cost-effective exploitation of renewable sources in order to cope with the improvement of the power supply service via local national grids, but mainly it may become a building block of rural electrification through integration within off-grid systems. This paper focuses on electrical energy storage in sub-Saharan Africa providing an overview of the main aspects of this theme. Indeed, the specific features of the power sector in sub-Saharan Africa are analyzed about the framework of application of electrical energy storage. The typical technologies implemented in this context and the status of the market as well as of the economic models to support the diffusion of storage together with renewable energy technologies are highlighted. Moreover, an overview of technical aspects such as storage capacity sizing and interface converters for integration with renewables are described. Finally, an experimental application of a hybrid micro-grid in rural Tanzania is presented. With this paper, our aim is to provide an overall view, within the main technical and non-technical aspects, of electrical energy storage in a context – sub-Saharan Africa – which has a huge potential, both in market terms, but also with regards to the possibility to develop and implement alternative technical solutions which may be integrated in the power systems of high income countries as well. © 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ available 1 november 2018

The paper retraces the implementation of a biogas energy programme within the Best Ray project run in Tanzania 2008–2011. The objective of the Best Ray project was to empower rural communities by providing them with modern and renewable energy technologies to better tackle Millennium Development Goals. An important activity of the project was the construction of a biogas system in secondary school solve a sanitation problem and provide the school with a free and reliable energy supply. After a field assessment, the project directed the resources to small domestic biogas installation rather than large institutional ones as future sustainability seemed to be better granted. Best Ray merged the Tanzanian Domestic Biogas Programme. Trainings were organized and 25 biogas plants constructed. The technology is simple and the design effective, but still the cost seems high for a rural context. Final beneficiaries are appreciating the technologies for reasons that were not predictable by those who ideated the project.

Purpose: Assessment on enucleated pig eyes of a novel and minimally invasive method for the continuous monitoring of intraocular pressure (IOP), based on a novel wireless contact lens sensor (CLS). Methods: The wireless CLS is a disposable silicone soft contact lens with a sensor embedded in it, allowing the wireless measurement of changes in corneal curvature induced by IOP variations. A CLS was adapted and tested on enucleated pig eyes. To demonstrate the measurement principle of the device, the enucleated pig eye was cannulated, allowing precise control of IOP. The CLS signal was then compared to the imposed IOP. Results: First, the IOP of enucleated pig eyes was changed between 11 and 14 mmHg, simulating ocular pulsation. Then, IOP was changed with static steps of 1 mmHg between 20 and 30 mmHg to assess the reproducibility and linearity of the CLS. In both cases, measurements from the CLS and IOP showed very good correlation. A calibration graph shows that the CLS is capable of monitoring the IOP of each individual eye with a reproducibility of ± 0.2 mmHg (95% confidence interval). Conclusion: The wireless CLS shows a good functionality to monitor the IOP on enucleated pig eyes. The device is placed in the same way as a soft disposable contact lens. This device would allow a minimally invasive and continuous monitoring of IOP over prolonged periods of up to 24 hr, regardless of patient activity, thus opening up new diagnostic and therapeutic methods to manage glaucoma.

PURPOSE. To present a novel and minimally invasive approach to intraocular pressure (IOP) monitoring based on a sensing contact lens. METHODS. The key element of this measurement method is a soft contact lens with an embedded microfabricated strain gauge allowing the measurement of changes in corneal curvature correlated to variations in IOP. A prototype of this sensing contact lens was adapted and tested on enucleated porcine eyes. To verify the measurement principle of the device, the posterior chamber of the pig eyes was cannulated and connected to a syringe pump and a pressure sensor for precise control of IOP. The measurements of the contact lens were then compared to the ones from the pressure sensor, while pressure variations were induced through the cannula. RESULTS. Enucleated porcine eyes were stimulated with increasing and decreasing ramps of IOP. Measurements from the sensing contact lens and from the pressure sensor showed very good correlation, proving the high potential of this new measurement principle. In this study, a typical signal from the sensing contact lens obtained during the experiments is presented and discussed. CONCLUSIONS. The sensing contact lens shows the potential for continuously monitoring IOP in enucleated porcine eyes. The ultimate step will be the validation of the system and the reproducibility of results in humans. The device is placed in the same way as a corrective contact lens, no anesthesia is required, and vision remains almost unimpaired. This device would allow minimally invasive IOP monitoring over prolonged periods, regardless of the patient's position and activity, thus opening up new diagnostic and therapeutic methods for the management of glaucoma.

Introduction Control of intraocular pressure fluctuation is of critical importance in glaucomatous patients. We present the first measurement of a novel and minimally invasive method to monitor relative intraocular pressure changes (IOP) on the human eye in-vivo by a wireless soft sensing contact lens. Aims and Methods The principle of measurement is based on the tiny changes in corneo-scleral curvature induced by variations in IOP. The measure is done by a soft silicone Contact Lens Sensor (CLS) with an embedded strain Gauge and allows wireless monitoring of IOP changes via an external antenna. The CLS was tested on five healthy volunteers. A decrease of IOP was induced using oculopression. Measurements of the ocular pulsation were also recorded. Results The filtred CLS signal is well correlated with the Goldmann tonometer. The ocular pulsation is well demonstrated and comparable to the signal obtained by a Dynamic Contour Tonometer. Discussion This is the first report of an in-vivo wireless continuous monitoring of the corneo-scleral deformation induced by the IOP changes and ocular pulsation on five human volunteers. Further clinical test are ongoing to characterize the dependence of the CLS signal amplitude on biometric and biomechanical eye properties. Conclusion This device potentially allows minimally invasive continuous measurement of relative changes in IOP, during prolonged periods, regardless of patient activity. It can thus for example replace 24-hour IOP.

Despite the electrical energy scenarios are quite different between industrialized countries and emerging and developing ones, for both contexts, energy storage systems could play a key role in the next future. Specifically, in emerging and developing countries, energy storage systems may allow a cost-effective exploitation of renewable sources in order to cope with energy security for centralized energy systems, but mainly to become a building block of rural electrification by off-grid power systems. In this paper a short overview of energy storage systems within the emerging and developing countries scenarios is reported. Specifically the paper provides a description of the typical configuration for batteries within off-grid systems and an overview of the typical economic models for batteries applications and the regulatory frameworks when off-grid applications are introduced. Finally the description of an experimental project in rural area of Tanzania points out the peculiar characteristics of batteries application in off-grid applications.

KAGRA is a new gravitational wave detector which aims to begin joint observation with Advanced LIGO and Advanced Virgo from late 2019. Here, we present KAGRA's possible upgrade plans to improve the sensitivity in the decade ahead. Unlike other state-of-the-art detectors, KAGRA requires different investigations for the upgrade since it is the only detector which employs cryogenic cooling of the test mass mirrors. In this paper, investigations on the upgrade plans which can be realized by changing the input laser power, increasing the mirror mass, and injecting frequency dependent squeezed vacuum are presented. We show how each upgrade affects to the detector frequency bands and also discuss impacts on gravitational-wave science. We then propose an effective progression of upgrades based on technical feasibility and scientific scenarios., Comment: 7 pages, 3 figures, Proceedings for the Fifteenth Marcel Grossmann Meeting, Rome, July 1-7, 2018

International audience; In more recent scholarship, beside the image of Iacopone da Todi as a genuine, learned poet, who is aware of all the challenges of poetic discourse associated with the transmission of a spiritual message, another image has emerged — that of an intellectual of his day who pondered not only the matter and form he was creating, but also the place he could find in literary history. This notion of Iacopone Todi as involved in political, stylistic, and literary concerns helps to highlight the authorial dignity of the poet and to extend the definition of the intellectual through that of the author in the literary and modern sense of the word. The creative project of the Laude resides in an attempt to combine love of literature and love of God ; literary innovation is part of his spiritual quest. The Laude demonstrate an intellectual journey based on the permanent oscillation between presence in the world and absence from it. The relation to the world which, somewhat ironically, lies somewhere between involvement and detachment. Within this opposition, the prophetic Laude certainly are the « literary demonstration » of Iacopone’s involvement in the religious and civil society of his day. From a similar point of view, in terms of readership and reception, the laudario acquires important pedagogical and didactic relevance that need to be emphasized. According to Iacopone, an individual’s perfection is not merely achieved by the relation of the inner self to itself, but also by the ability to face worldly realities. This perfection is not the outcome of pure instinct, but rather of an enlightening intellectual process. Thus, the poet considers the Laude as the site of the development of a pedagogic action, or even of a pedagogic project, which is integral to genuine « spiritual guidance ».; Il ne fait plus aucun doute qu’à côté de la figure de Jacopone da Todi, vrai poète, cultivé, connaissant les enjeux du discours poétique associé à la transmission du message spirituel, s’est dessinée celle d’un intellectuel de son temps, réfléchissant à la matière et à la forme qu’il est en train de créer, et à la place qu’il peut trouver dans la diachronie littéraire. Cette image de Jacopone, intellectuel engagé aussi bien dans les questions politiques que dans les réflexions littéraires et stylistiques, permet de mettre en avant la dignité auctoriale du poète et de prolonger la définition de l’intellectuel par celle de l’auteur, au sens moderne et littéraire du terme.Le programme et la créativité des Laude se situent dans la tentative de concilier le désir des Lettres et l’amour de Dieu : les conquêtes littéraires s’inscrivent dans la quête spirituelle. Les laude démontrent un parcours intellectuel fondé sur une oscillation permanente entre présence et absence au monde : le rapport au monde que suppose l’ironie se situe entre engagement et détachement. A l’intérieur de cette opposition, les laude prophétiques sont assurément une manifestation « littéraire » de l’intervention de Jacopone dans les problèmes de la société religieuse et civile contemporaines. Et c’est dans une perspective analogue que l’on peut relever une très forte indexation pédagogique et didactique replaçant le laudario dans la réalité de l’existence d’un public et de la réception de l’œuvre.Selon Jacopone, la perfection de l’individu ne se réalise pas seulement dans le rapport intérieur de soi à soi mais aussi dans la confrontation avec les réalités terrestres ; cette perfection n’est pas le fruit du pur instinct mais d’une intellectualisation éclairante. Aussi, le poète considère-t-il les Laude comme le lieu de développement d’une action pédagogique, voire d’un programme, s’inscrivant dans l’activité plus large d’une véritable « direction spirituelle ».