Optical transmitter for time-bin encoding Quantum Key Distribution

We introduce an electro-optical arrangement that is able to produce time-bin encoded symbols with the decoy state method over a standard optical fiber in the C-band telecom window. The device consists of a specifically designed pulse pattern generator for pulse production, a field-programmable gate array that controls timing and synchronization. The electrical pulse output drive a sequence of intensity modulators acting on a continuous laser that deliver bursts of weak optical pulse pairs of discrete intensity values. Such transmitter allows for the generation of all the quantum states needed to implement a discrete variable Quantum Key Distribution protocol over a single-mode fiber channel. Symbols are structured in bursts; the minimum relative delay between pulses is 1.25 ns, and the maximum symbol rate within a burst is 200 MHz. We test the transmitter on simulated optical channels of 7dB and 14dB loss, obtaining maximum extractable secure key rates of 3.0 kb/s and 0.57 kb/s respectively. Time bin state parameters such as symbol rate, pulse separation and intensity ratio between signal and decoy states can be easily accessed and changed, allowing the transmitter to adapt to different experimental conditions and contributing to standardization of QKD implementations.Comment: 8 pages, 4 figure

Somatic evolution and global expansion of an ancient transmissible cancer lineage

Made available in DSpace on 2019-10-06T15:53:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-08-02GPD Charitable TrustLeverhulme TrustThe canine transmissible venereal tumor (CTVT) is a cancer lineage that arose several millennia ago and survives by “metastasizing” between hosts through cell transfer. The somatic mutations in this cancer record its phylogeography and evolutionary history. We constructed a time-resolved phylogeny from 546 CTVT exomes and describe the lineage's worldwide expansion. Examining variation in mutational exposure, we identify a highly context-specific mutational process that operated early in the cancer's evolution but subsequently vanished, correlate ultraviolet-light mutagenesis with tumor latitude, and describe tumors with heritable hyperactivity of an endogenous mutational process. CTVT displays little evidence of ongoing positive selection, and negative selection is detectable only in essential genes. We illustrate how long-lived clonal organisms capture changing mutagenic environments, and reveal that neutral genetic drift is the dominant feature of long-term cancer evolution.Transmissible Cancer Group Department of Veterinary Medicine University of CambridgeAnimal Management in Rural and Remote Indigenous Communities (AMRRIC)World VetsAnimal Shelter Stichting Dierenbescherming SurinameSikkim Anti-Rabies and Animal Health Programme Department of Animal Husbandry Livestock Fisheries and Veterinary Services Government of SikkimRoyal (Dick) School of Veterinary Studies Roslin Institute University of Edinburgh Easter Bush CampusConserLab Animal Preventive Medicine Department Faculty of Animal and Veterinary Sciences University of ChileCorozal Veterinary Hospital University of PanamáSt. George's UniversityNakuru District Veterinary Scheme LtdAnimal Medical CentreInternational Animal Welfare Training Institute UC Davis School of Veterinary MedicineCentro Universitário de Rio Preto (UNIRP)Department of Clinical and Veterinary Surgery São Paulo State University (UNESP)Ladybrand Animal ClinicVeterinary Clinic Sr. Dog'sWorld Vets Latin America Veterinary Training CenterNational Veterinary Research InstituteAnimal ClinicIntermunicipal Stray Animals Care Centre (DIKEPAZ)Animal Protection Society of SamoaFaculty of Veterinary Science University of ZuliaVeterinary Clinic BIOCONTROLFaculty of Veterinary Medicine School of Health Sciences University of ThessalyVeterinary Clinic El Roble Animal Healthcare Network Faculty of Animal and Veterinary Sciences University of ChileOnevetGroup Hospital Veterinário BernaUniversidade Vila VelhaVeterinary Clinic ZoovetservisÉcole Inter-états des Sciences et Médecine Vétérinaires de DakarDepartment of Small Animal Medicine Faculty of Veterinary Medicine Utrecht UniversityVetexpert Veterinary GroupVeterinary Clinic Lopez QuintanaClinique Veterinaire de Grand Fond Saint Gilles les BainsDepartment of Veterinary Sciences University of MessinaFacultad de Medicina Veterinaria y Zootecnia Universidad Autónoma del Estado de MéxicoSchool of Veterinary Medicine Universidad de las AméricasCancer Development and Innate Immune Evasion Lab Champalimaud Center for the UnknownTouray and Meyer Vet ClinicHillside Animal HospitalKampala Veterinary SurgeryAsavet Veterinary CharitiesVets Beyond BordersFaculty of Veterinary Medicine Autonomous University of YucatanLaboratorio de Patología Veterinaria Universidad de CaldasInterdisciplinary Centre of Research in Animal Health (CIISA) Faculty of Veterinary Medicine University of LisbonFour Paws InternationalHelp in SufferingVeterinary Clinic Dr José RojasDepartment of Biotechnology Balochistan University of Information Technology Engineering and Management SciencesCorozal Veterinary ClinicVeterinary Clinic VetmasterState Hospital of Veterinary MedicineJomo Kenyatta University of Agriculture and TechnologyLaboratory of Biomedicine and Regenerative Medicine Department of Clinical Sciences Faculty of Animal and Veterinary Sciences University of ChileFaculty of Veterinary and Agricultural Sciences University of MelbourneAnimal Anti Cruelty LeagueClinical Sciences Department Faculty of Veterinary Medicine BucharestDepartment of Pathology Faculty of Veterinary Medicine Ankara UniversityFaculty of Veterinary Sciences National University of AsuncionLilongwe Society for Protection and Care of Animals (LSPCA)Wellcome Sanger InstituteDepartment of Cellular and Molecular Medicine University of California San DiegoDepartment of Clinical and Veterinary Surgery São Paulo State University (UNESP)Leverhulme Trust: 102942/Z/13/

Recurrent horizontal transfer identifies mitochondrial positive selection in a transmissible cancer

Abstract: Autonomous replication and segregation of mitochondrial DNA (mtDNA) creates the potential for evolutionary conflict driven by emergence of haplotypes under positive selection for ‘selfish’ traits, such as replicative advantage. However, few cases of this phenomenon arising within natural populations have been described. Here, we survey the frequency of mtDNA horizontal transfer within the canine transmissible venereal tumour (CTVT), a contagious cancer clone that occasionally acquires mtDNA from its hosts. Remarkably, one canine mtDNA haplotype, A1d1a, has repeatedly and recently colonised CTVT cells, recurrently replacing incumbent CTVT haplotypes. An A1d1a control region polymorphism predicted to influence transcription is fixed in the products of an A1d1a recombination event and occurs somatically on other CTVT mtDNA backgrounds. We present a model whereby ‘selfish’ positive selection acting on a regulatory variant drives repeated fixation of A1d1a within CTVT cells

Microstructural study of nanocrystalline pure and doped tin dioxide to be used for resistive gas sensors

Nanocrystalline pure and doped SnO2 have been intensively studied for a long time to build resistive gas sensors. However, it is still useful to synthesize nanopowders with the smallest crystallite size to build devices. A modified gel-combustion method and a novel reactive oxidation process are proposed for nanopowders synthesis and results are compared. Materials have been characterized by XRD, Scherrer equation to evaluate the crystallite size; BET absorption to determine specific area and HRTEM to observe the crystallites (evaluating their mean size and distribution); defects and effect of calcination treatments are also considered. Previous studies have shown that if nano-SnO2 replaces the conventional microcrystalline-SnO2 to build resistive gas sensors, sensitivity increases (>30%) and the operation temperature considerably decreases. A heating and measuring system has been designed for achieving low power consumption and uses pulsed heating operation. This method of electrical control and measurement is operated intermittently, with "heating" and "readout" cycles (readout: signal of sensitive film).Fil: Bianchetti, Mario Fidel. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Arrieta, Cristian L.. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; ArgentinaFil: Walsoe, Noemi Elizabeth. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; Argentin

High Precision Gas Sensors Built With Ceramic Nanofilms

Semiconductores como el SnO2 (puros o dopados), han sido intensamente utilizados para construir sensores de gases de película gruesa de tipo resistivo que permitan detectar gases tóxicos o combustibles: NOx, SO2, CO, H2, CH4 o VOCs (Volatile Organic Compounds). Los sensores convencionales basados en SnO2 microcristalino resultan interesantes debido a su alta sensibilidad y a su temperatura de operación (Top) relativamente baja (350-450) oC. Los autores han probado que la sensibilidad de varios de los sensores, construidos en el DEINSO-CITEDEF, aumenta en (30-35)% y la Top disminuye de (350-450)ºC a un rango de (180-220)ºC si el SnO2 microcristalino convencional es reemplazado por SnO2 nanocristalino para la construcción de los dispositivos. En consecuencia, en los últimos años, se han sintetizado polvos nanocristalinos, con una alta relación [superficie/volumen] y se han empleado con mejoras considerables en los dispositivos. Los sensores de tipo resistivo operan en presencia de oxígeno y se han estudiado los mecanismos de sensado para los casos de SnO2 micro- y nanocristalino. El objetivo de este trabajo fue construir un sensor de película fina con SnO2 puro nanocristalino para obtener un dispositivo para detectar ppm de hidrógeno en aire y optimizar su comportamiento. Se eligió construir el sensor de H2 para poner a punto las técnicas de película fina multicapas que luego se usarán en la construcción de un sensor fabricado con SnO2 dopado con Cu2O para medir ppm de SH2 (g) en aire. El SnO2 nanocristalino puro para medir H2 fue sintetizado por tres técnicas de película fina cuyos resultados se compararon y caracterizaron por DRX, determinando el tamaño de cristalita (ecuación de Scherrer) y estudiando las tensiones generadas por cada film. Las películas delgadas debido a su espesor, a su depósito en capas múltiples y a los tratamientos térmicos a los cuales son sometidas, producen tensiones las que, a su vez, causan defectos tales como dislocaciones, bordes de grano, interfaces o intercaras, aglomeraciones de vacancias, etc. que aceleran los procesos difusionales de los gases en los materiales sensibles y, en consecuencia, mejoran la performance del sensor. También se caracterizaron los films por la técnica de absorción BET y se observó la morfología por HRTEM. Estas dos últimas técnicas se efectuaron en los primeros crecimientos. Técnicas de. SEM se emplearon para medir espesores de los films y la rugosidad o relieve de las superficies. Se realizaron las mediciones de la sensibilidad del sensor de H2 y se compararon con datos dereferencia propia de los autores. Se describe también el circuito electrónico de control del sensor (de doble meandro obtenido por MEMS) que se ha mejorado mediante un nuevo circuito de medición microcontrolado, modular y transportable, que permite programar la temperatura de trabajo, los modos de operación del sensado, la calefacción y los tiempos de conmutación entre ellos.The semiconductor metallic oxides, like pure or doped SnO2, have been intensively used for resistive thick film gas sensors to detect toxic, fuel or explosive gases: NOx, SO2, CO, H2, CH4 or VOCs (Volatile Organic Compounds) using thick film techniques. For many years, SnO2, gas sensors (as based on microcrystalline materials) have been considered by its high sensitivity and relatively low operation temperature Top=350oC-450oC for many years. If conventional microcrystalline SnO2 is substituted by nanocrystalline SnO2 to build the sensors, the authors have proved that sensor sensitivity increases from 30% to 35% and that the Top decreases from (350-450)ºC to a range (180-220)ºC. In the last decade, nanocrystalline powders with high [surface/volume] ratio have been synthesized and applied reaching a considerable improvement of devices. As sensors work in oxygen atmosphere, the sensing mechanisms have been carefully studied for micro- and nanocrystalline SnO2. In this case, a H2 (g) sensor built with pure SnO2 was chosen to carry out the multi-layered thin film techniques which will be used in a future experience to build a doped with Cu2O - SnO2 sensor to measure SH2 (g) ppm in air. At first, H2 (g) sensors were built at DEINSO with thick films. Techniques to build the layered nanocrystalline pure SnO2 thin films were performed and they are going to be optimized. The nanocrystalline pure SnO2 has been synthesized by three thin film techniques to compare results. Nanomateriales were characterized by DRX: crystallite size was measured by Scherrer equation and lattice stresses as produced by the different synthesis methods were also studied by X-rays diffraction. The thin films due to their thickness, to their deposit in multiple layers and to the thermal treatments to which they are subjected, produce stresses causing defects, such as: dislocations, grain boundaries, interfaces, vacancies clusters, etc. These defects accelerate the gases diffusional processes in the sensor, improving, in consequence, the device performance. Adsorption BET techniques and HRTEM morphology studies were performed on films. SEM was used to measure the films thickness and the surface relief or rugosity. The double meander electronic circuit (built by MEMS) to control sensors (already patented by the authors) was also improved by a new controlled, modular and portable circuit, being able to program the working temperature, the sensing operation modes, the heating and the commutation time between themFil: Poiasina, Mariana Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Bianchetti, Mario Fidel. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentina. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; ArgentinaFil: Wittemberg, Víctor. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; ArgentinaFil: Arrieta, Cristian L.. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; ArgentinaFil: Lacomi, Héctor Alberto. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; ArgentinaFil: Walsoe, Noemi Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentin

Gas Sensors Built with Nanomaterials and Provided with a Heating Double Purpose Hot-plate

Pure or doped SnO2, has been used to build resistive type gas sensors from several decades. This subject has been retaken using pure or doped nanocrystalline SnO2 to build the sensors, finding considerable advantages in devices performance. The sensors working temperature (Tw) decreases from (350-450) 0C to (180-200) 0C in comparison with that of devices built with microcrystalline conventional material. Sensitivity of sensors built with nanocrystalline material in comparison with that of devices built with conventional microcrystalline material, increases from 30 % to 37 %. In this work, SnO2 is synthesized using two different modified techniques based on gel-combustion and reactive oxidation and results of both syntheses are compared. Nanomaterials are characterised with X-ray diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and Field Emission Electron Scanning Microscopy (FESEM) and absorption techniques (BET). An electronic system, already patented by the authors, enables to alternatively measure the sensor resistivity (which is proportional to the adsorbed gas concentration) and set a constant working temperature, thus contributing to considerably save energy

Flares in IIMs and the timeline following COVID-19 vaccination: a combined analysis of the COVAD-1 and -2 surveys

Objectives: Disease flares in the post-coronavirus disease 2019 (COVID-19) vaccination period represent a prominent concern, though risk factors are poorly understood. We studied these flares among patients with idiopathic inflammatory myopathies (IIMs) and other autoimmune rheumatic diseases (AIRDs). Methods: The COVAD-1 and -2 global surveys were circulated in early 2021 and 2022, respectively, and we captured demographics, comorbidities, AIRDs details, COVID-19 infection history and vaccination details. Flares of IIMs were defined as (a) patient self-reported, (b) immunosuppression (IS) denoted, (c) clinical sign directed and (d) with >7.9-point minimal clinically significant improvement difference worsening of Patient-Reported Outcomes Measurement Information System (PROMIS) PROMISPF10a score. Risk factors of flares were analysed using regression models. Results: Of 15 165 total respondents, 1278 IIMs (age 63 years, 70.3% female, 80.8% Caucasians) and 3453 AIRDs were included. Flares of IIM were seen in 9.6%, 12.7%, 8.7% and 19.6% patients by definitions (a) to (d), respectively, with a median time to flare of 71.5 (10.7-235) days, similar to AIRDs. Patients with active IIMs pre-vaccination (OR 1.2; 95% CI 1.03, 1.6, P = 0.025) were prone to flares, while those receiving rituximab (OR 0.3; 95% CI 0.1, 0.7, P = 0.010) and AZA (OR 0.3, 95% CI 0.1, 0.8, P = 0.016) were at lower risk. Female gender and comorbidities predisposed to flares requiring changes in IS. Asthma (OR 1.62; 95% CI 1.05, 2.50, P = 0.028) and higher pain visual analogue score (OR 1.19; 95% CI 1.11, 1.27, P < 0.001) were associated with disparity between self-reported and IS-denoted flares. Conclusion: A diagnosis of IIMs confers an equal risk of flares in the post-COVID-19 vaccination period to AIRDs, with active disease, female gender and comorbidities conferring a higher risk. Disparity between patient- and physician-reported outcomes represents a future avenue for exploration

Vaccine hesitancy decreases in rheumatic diseases, long-term concerns remain in myositis: A comparative analysis of the COVAD surveys

Objective: COVID-19 vaccines have a favorable safety profile in patients with autoimmune rheumatic diseases (AIRDs) such as idiopathic inflammatory myopathies (IIMs); however, hesitancy continues to persist among these patients. Therefore, we studied the prevalence, predictors and reasons for hesitancy in patients with IIMs, other AIRDs, non-rheumatic autoimmune diseases (nrAIDs) and healthy controls (HCs), using data from the two international COVID-19 Vaccination in Autoimmune Diseases (COVAD) e-surveys. Methods: The first and second COVAD patient self-reported e-surveys were circulated from March to December 2021, and February to June 2022 (ongoing). We collected data on demographics, comorbidities, COVID-19 infection and vaccination history, reasons for hesitancy, and patient reported outcomes. Predictors of hesitancy were analysed using regression models in different groups. Results: We analysed data from 18 882 (COVAD-1) and 7666 (COVAD-2) respondents. Reassuringly, hesitancy decreased from 2021 (16.5%) to 2022 (5.1%) (OR: 0.26; 95% CI: 0.24, 0.30, P < 0.001). However, concerns/fear over long-term safety had increased (OR: 3.6; 95% CI: 2.9, 4.6, P < 0.01). We noted with concern greater skepticism over vaccine science among patients with IIMs than AIRDs (OR: 1.8; 95% CI: 1.08, 3.2, P = 0.023) and HCs (OR: 4; 95% CI: 1.9, 8.1, P < 0.001), as well as more long-term safety concerns/fear (IIMs vs AIRDs - OR: 1.9; 95% CI: 1.2, 2.9, P = 0.001; IIMs vs HCs - OR: 5.4 95% CI: 3, 9.6, P < 0.001). Caucasians [OR 4.2 (1.7-10.3)] were likely to be more hesitant, while those with better PROMIS physical health score were less hesitant [OR 0.9 (0.8-0.97)]. Conclusion: Vaccine hesitancy has decreased from 2021 to 2022, long-term safety concerns remain among patients with IIMs, particularly in Caucasians and those with poor physical function