V-Shape Liquid Crystal-Based Retromodulator Air to Ground Optical Communications

This paper describes the use of a 2D liquid crystal retro-modulator as a free space, wireless, optical link. The retro-modulator is made up of a retro-reflecting cornercube onto which 2 cascaded V-shape smectics liquid crystal modulators are mounted. The communication link differs with respect to more conventional optical links in not using amplitude (nor frequency) modulation, but instead state-of-polarisation (SOP) modulation known as Polarisation Shift Keying (PolSK). PolSK has the advantage over amplitude modulation, that it is less sensitive to changes in the visibility of the atmosphere, and increases inherently the bandwidth of the link. The implementation of PolSK both in liquid crystal based and in retro-modulated communication are novelties

Asymmetric switching and charge transport in AFLC devices with dissimilar alignment layers

Surface stabilized antiferroelectric liquid crystal (AFLC) devices with dissimilar alignment layers on the two surfaces are characterized by a shift in the electro-optical response [1] so that it is symmetric with respect to a nonzero voltage (figure 1). Because of this shift, the switching state of a pixel which is initially set by applying a short, selection, voltage pulse, may be maintained without applying any holding, bias, voltage. The stability at zero volts, together with the inherent range of grey levels, typical for antiferroelectric liquid crystals, has some potentially very interesting applications. Generally, the magnitude of the voltage shift changes slowly over time, depending on the driving conditions and the materials used. This varying asymmetry is an important obstacle for the implementation of this technology in real devices. Fig. 1. Asymmetric transmission–voltage characteristic of an AFLC cell with dissimilar alignment layers. 2. The influence of charge in asymmetric AFLC devices Charges in AFLCs can considerably influence the switching behavior of the device [2][3]. Measurements of the electric current flowing towards the electrodes of the device when a voltage step is applied can elucidate the nature and the behavior of these charge

External Water Subcooling To Improve The Performance Of A CO2 Heat Pump For Water Heating That Uses Greywater As Heat Source

The use of CO2 heat pumps for water heating combined with energy recovery from greywater is a promising technology that can help to improve the efficiency of both domestic hot water (DHW) generation and space heating. A key aspect to keep in mind during the design of any CO2 refrigeration or heat pump system is the fact that the optimal gas cooler pressure in a transcritical CO2 cycle is mainly dependent on the refrigerant temperature at the gas cooler outlet. In space heating applications as well as DHW generation, operating conditions require high temperatures of refrigerant at the gas cooler outlet. That can lead to very high optimal pressures, in some cases, even higher than the maximum pressure of the system. The use of a subcooler fed by the same greywater used in the evaporator can help to reduce the optimal pressure and improve the efficiency of the system. When the greywater passes first through the subcooler, the evaporation temperature can be increased while the optimal pressure is reduced. When the greywater passes first through the evaporator, the evaporation temperature remains constant, but the refrigerant temperature at the gas cooler outlet can be reduced to a lower value. So, the order in which the water flows through subcooler and evaporator can affect the system’s efficiency and the best control strategy will depend on the operating conditions. First, a numerical model is used to model an experimental facility and model results are compared to some preliminary experimental results. Finally, this contribution analyses the influence that the greywater conditions (temperature, mass flow rate and flow order), as well as the subcooler efficiency have in the system’s efficiency depending on the operating conditions (DHW generation or space heating) in order to stablish the control strategy that optimize the system’s performance

Experimental Evaluation of the Factors That Influence CylindricalWater Projection Devices against IEDs

Terrorists usually employ Improvised Explosive Devices (IEDs) to cause maximum damage with a single action, in asymmetric war scenarios. In the counter-terrorism fight, bomb disposal specialists have to combat these instruments by safeguarding their lives, avoiding fortuitous IED explosion, and preserving evidence of the device that could lead to the capture of the perpetrators. Some very effective deactivation tools that combine these features are high-speed water-explosive projection devices. To understand and quantify the impacts of the many factors that intervene in their operation and effectiveness, extensive experimental tests should be conducted. However, Operations Research techniques allow robust results to be obtained by minimizing experiments. This study focuses on the use of Design of Experiments (DoE), with a factorial experiment plan divided into two levels, to analyze the influence of the amount of explosive, the diameter of the device (that is, the mass of water to be projected), the density of the water, the distance at which the IED is located, and the resistance of the inner tube material. Results show that the mass of explosive, the diameter of the device, the interaction of the mass of explosive and the density of the water, and the interaction between the resistance of the inner tube and the diameter of the container have a strong influence on the speed of projected water.This work was supported by the Cuerpo Nacional de Policía and Centro Universitario de la Defensa de Zaragoza (grant number: CUD2020-21)

Patients' perceptions on shared decision making during prescription of subcutaneous biological drug treatments for inflammatory arthritis: the RHEU-LIFE survey

Short report[Abstract] Objectives: The aim of this study was to explore the preferences of patients with rheumatic diseases and their perceived experience regarding participation in shared decision making (SDM) when they were prescribed a subcutaneous (SC) biological drug. Methods: A printed survey was handed to 1,000 patients with inflammatory rheumatic diseases treated with SC biological drug. The survey included closed questions about preferences regarding decision making and about patients' experience when they were prescribed an SC biological drug. Descriptive statistics were performed with stratification by patient profiles, using chi-square for comparisons between groups. Results: A total of 592 surveys were received (response rate 59.2%, mean age 51.7 years, 57.6% women). Some 28.2% of patients reported preferring to take part in treatment selection, a percentage that was higher in younger patients, in those with higher academic degree and in those who search information in sources different to that of health care professionals. Over half of patients (56.3%) perceived that the rheumatologist considered their opinion when prescribing an SC biological drug, a percentage higher in younger people. Only in 40.8% of cases did the patients' preference match their perception of their participation in the process. No differences were observed by sex, disease or number of biologics. Conclusions: Patients with inflammatory rheumatic diseases want information about their treatments but mostly leave the prescription decision to the rheumatologist. Younger people, or those with higher academic degree, more often want to participate in the SDM. There are discrepancies between patient preferences and perceptions of this process

Cymantrene–Triazole "Click" Products: Structural Characterization and Electrochemical Properties

We report the first known examples of triazole-derivatized cymantrene complexes (η5-[4-substituted triazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I), obtained via a “click” chemical synthesis, bearing a phenyl, 3-aminophenyl, or 4-aminophenyl moiety at the 4-position of the triazole ring. Structural characterization data using multinuclear NMR, UV–vis, ATR-IR, and mass spectrometric methods are provided, as well as crystallographic data for (η5-[4-phenyltriazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I) and (η5-[4-(3-aminophenyl)triazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I). Cyclic voltammetric characterization of the redox behavior of each of the three cymantrene–triazole complexes is presented together with digital simulations, in situ infrared spectroelectrochemistry, and DFT calculations to extract the associated kinetic and thermodynamic parameters. The trypanocidal activity of each cymantrene–triazole complex is also examined, and these complexes are found to be more active than cymantrene alone

Electrooptic characterization of tunable cylindrical liquid crystal lenses

In this work, one-dimensional arrays of cylindrical adaptive liquid crystal lenses were manufactured and characterized; and test devices were filled with nematic liquid crystal. Comb interdigitated electrodes were designed as a mask pattern for the control electrode on the top glass substrates. A radial graded refractive index along each microsized lens was achieved by fabricating a layer of high resistance sheet deposited as a control electrode. These tunable lenses were switched by applying amplitude and frequency optimized waveforms on the control electrode. Phase profiles generated by the radial electric field distribution on each lens were measured by a convectional interferometric technique

The chaperonin CCT controls T cell receptor-driven 3D configuration of centrioles

T lymphocyte activation requires the formation of immune synapses (IS) with antigen-presenting cells. The dynamics of membrane receptors, signaling scaffolds, microfilaments, and microtubules at the IS determine the potency of T cell activation and subsequent immune response. Here, we show that the cytosolic chaperonin CCT (chaperonin-containing TCP1) controls the changes in reciprocal orientation of the centrioles and polarization of the tubulin dynamics induced by T cell receptor in T lymphocytes forming an IS. CCT also controls the mitochondrial ultrastructure and the metabolic status of T cells, regulating the de novo synthesis of tubulin as well as posttranslational modifications (poly-glutamylation, acetylation, ?1 and ?2) of ??-tubulin heterodimers, fine-tuning tubulin dynamics. These changes ultimately determine the function and organization of the centrioles, as shown by three-dimensional reconstruction of resting and stimulated primary T cells using cryo-soft x-ray tomography. Through this mechanism, CCT governs T cell activation and polarity.Cryo-SXT work was supported by ALBA Synchrotron standard proposals 2015021148 and 2016021638 to F.J.C., N.B.M.-C., and J.M.V. This study was supported by grants SAF2017-82886-R (to F.S.-M.), PID2019-105872GB-I00/AEI/10.13039/501100011033 (AEI/FEDER, UE), BFU2016-75984 (to J.M.V.), and BIO2015-67580-P and PGC2018-097019-B-I00 (to J.V.) from the Spanish Ministry of Economy and Competitiveness (MINECO), grants INFLAMUNE-S2017/BMD-23671 (to F.S.-M.) and P2018/NMT-4389 (to J.M.V.) from the Comunidad de Madrid, ERC-2011-AdG 294340-GENTRIS (to F.S.-M.), a 2019 grant from the Ramón Areces Foundation “Ciencias de la Vida y la Salud” and a 2018 grant from Ayudas Fundación BBVA a Equipos de Investigación Científica (to F.S.-M.), and grants PRB3 (IPT17/0019-ISCIII-SGEFI/ERDF), the Fundació Marató TV3 (grant 122/C/2015), and “La Caixa” Banking Foundation (HR17-00016 to FSM and HR17-00247 to J.V.). D.T. is supported by a PhD fellowship from La Caixa Foundation. Work in the Vernos lab was supported by the grant CSD2006-00023 from the Spanish Ministry of Science and Innovation and grants BFU2012-37163 and BFU2015-68726-P from the Spanish Ministry of Economy and Competitiveness. The CRG acknowledges support of the Spanish Ministry of Science and Innovation to the EMBL partnership, the Centro de Excelencia Severo Ochoa, and the CERCA Programme/Generalitat de Catalunya. CIBER Cardiovascular (Fondo de Investigación Sanitaria del Instituto de Salud Carlos III and co-funding by Fondo Europeo de Desarrollo Regional FEDER). The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Spanish Ministry of Economy and Competitiveness (MINECO) and the Pro-CNIC Foundation and is a Severo Ochoa Center of Excellence (MINECO award SEV-2015- 0505). The Centro Nacional de Biotecnología (CNB) is a Severo Ochoa Center of Excellence (MINECO award SEV 2017-0712). Funding agencies have not intervened in the design of the studies, with no copyright over the stud

Validation of electrodeposited 241Am alpha-particle sources for use in liquified gas detectors at cryogenic temperatures

This paper describes a procedure for the validation of alpha-particle sources (exempt unsealed sources) to be used in experimental setups with liquefied gases at cryogenic temperatures (down to -196 C) and high vacuum. These setups are of interest for the development and characterization of neutrino and dark matter detectors based on liquid argon, among others. Due to the high purity requirements, the sources have to withstand high vacuum and cryogenic temperatures for extended periods. The validation procedure has been applied to 241Am sources produced by electrodeposition.Comment: 5 page