Resumen de tesis. Development of ultra-stable characterization techniques for ultrashort laser beams

[EN]The dramatic evolution that the laser Science has undergone in the last six decades, and particularly in the field of ultrashort pulses, has been accompanied by breakthrough advances in the development of techniques for their characterization. Despite the large number of characterization techniques developed in the last two decades, it is still necessary to Implement simpler and more robust techniques that can also operate in multiple spectral ranges. This Thesis is devoted to the study and development of temporal and spatiotemporal characterization techniques with compact and stable configurations, which are versatile, e.g., to analyze ultrashort laser beams with different temporal durations and in various spectral regions. The structure of this Thesis is made up of four main blocks. Firstly, a brief introduction to ultrafast optical metrology and the state of the art of spatial, temporal and spatiotemporal characterization techniques is presented in Part I. Then, Part II is focused on the review and extension of the capabilities of the amplitude swing temporal characterization technique, demonstrating three key advances: operation in different spectral regions from visible to near-infrared, with a tunability range spanning of more than one octave; Characterization of ultrashort pulses in the few-cycle regime; or study of the implementation with different amplitude modulation schemes. In addition, a new retrieval algorithm is developed to analyze the amplitude swing traces based on differential evolution strategies. Thirdly, the fundamentals, operation range and experimental demonstration of a spatiotemporal characterization technique based on bulk lateral shearing interferometry are depicted in Part III. Furthermore, the technique is applied to characterize complex spatiotemporal couplings, like constant and time-varying optical vortices or the aberrations when focusing with astigmatic lenses. Finally, the main conclusions of the work and future perspectives are discussed in Part IV[ES]La drástica evolución que ha experimentado la ciencia láser en las últimas seis décadas, y en particular en el campo de los pulsos ultracortos, ha ido acompañada de grandes avances en el desarrollo de técnicas para su caracterización. A pesar de la gran cantidad de métodos de caracterización desarrollados en las últimas dos décadas, aún es necesario implementar sistemas más simples y robustos que también puedan operar en múltiples rangos espectrales. Esta Tesis está dedicada al estudio y desarrollo de técnicas de caracterización temporal y espaciotemporal con configuraciones compactas y estables, que sean versátiles para, por ejemplo, analizar haces láser ultracortos con diferentes duraciones temporales y en diversas regiones espectrales. La estructura de la Tesis está dividida en cuatro bloques principales. En primer lugar, en la Parte I se presenta una breve introducción a la metrología óptica ultrarrápida y los avances de las técnicas de caracterización espacial, temporal y espaciotemporal a lo largo de los últimos años. Después, la Parte II se enfoca en la revisión y extensión de las capacidades de la técnica de caracterización temporal amplitude swing, demostrando tres avances clave: operación en diferentes regiones espectrales desde visible hasta infrarrojo cercano, con un rango de sintonizabilidad que abarca más de una octava; caracterización de pulsos ultracortos en régimen de pocos ciclos; o estudio de diferentes esquemas de modulación de amplitud. Además, se implementa un nuevo algoritmo de reconstrucción para analizar las trazas del sistema amplitude swing basado en las estrategias Differential Evolution. En tercer lugar, en la Parte III se describen los fundamentos, el rango de operación y la demostración experimental de una técnica de caracterización espaciotemporal basada en la interferometría lateral compacta (bulk lateral shearing interferometry). Además, la técnica se emplea para caracterizar acoplamientos espaciotemporales complejos, como son los vórtices ópticos constantes y variables en el tiempo o las aberraciones introducidas al focalizar haces láser con lentes astigmáticas. Finalmente, en la Parte IV se resumen las principales conclusiones y futuras líneas de trabajo.Thesis memory and supplementary material folder: Vídeo 1 ("VideoThesis_GeneralizingAswing_Noise.avi"), Noise analysis amplitude swing configurations video. Vídeo 2 ("VideoThesis_Vortices_ProofOfConcept.avi"), Proof of concept spatiotemporal technique video. Vídeo 3 ("VideoThesis_Vortex_NIR_Lneg1.avi"), Near-infrared vortex video: orbital angular momentum of −1. Vídeo 4 ("VideoThesis_Vortex_NIR_L1.avi"), Near-infrared vortex video: orbital angular momentum of +1. Vídeo 5 ("VideoThesis_Vortex_NIR_L3.avi"), Near-infrared vortex video: orbital angular momentum of +3. Vídeo 6 ("VideoThesis_Vortex_VIS_Lneg2.avi"), Visible vortex video: orbital angular momentum of -2. Vídeo 7 ("VideoThesis_Vortex_VIS_L2.avi"), Visible vortex video: orbital angular momentum of +2. Vídeo 8 ("VideoThesis_Vortex_VIS_L4.avi"), Visible vortex video: orbital angular momentum of +4. Vídeo 9 ("VideoThesis_TimeVaryingVortex_Exp.avi"), Time varying vortex video: Experiment. Vídeo 10 ("VideoThesis_TimeVaryingVortex_Sim.avi"), Time varying vortex video: Simulation. Vídeo 11 ("VideoThesis_Astigmatic_Biconvergent.avi"), Astigmatic beam video: z = da = 49 cm. Vídeo 12 ("VideoThesis_Astigmatic_ConvDiv.avi"), Astigmatic beam video: z = db = 137 cm

Clinical features and outcomes of Streptococcus anginosus group infective Endocarditis: a multicenter matched cohort study

[EN] Background. Although Streptococcus anginosus group (SAG) endocarditis is considered a severe disease associated with abscess formation and embolic events, there is limited evidence to support this assumption. Methods. We performed a retrospective analysis of prospectively collected data from consecutive patients with definite SAG endocarditis in 28 centers in Spain and Italy. A comparison between cases due to SAG endocarditis and viridans group streptococci (VGS) or Streptococcus gallolyticus group (SGG) was performed in a 1:2 matched analysis. Results. Of 5336 consecutive cases of definite endocarditis, 72 (1.4%) were due to SAG and matched with 144 cases due to VGS/ SGG. SAG endocarditis was community acquired in 64 (88.9%) cases and affected aortic native valve in 29 (40.3%). When comparing SAG and VGS/SGG endocarditis, no significant differences were found in septic shock (8.3% vs 3.5%, P = .116); valve disorder, including perforation (22.2% vs 18.1%, P = .584), pseudoaneurysm (16.7% vs 8.3%, P = .108), or prosthesis dehiscence (1.4% vs 6.3%, P = .170); paravalvular complications, including abscess (25% vs 18.8%, P = .264) and intracardiac fistula (5.6% vs 3.5%, P = .485); heart failure (34.7% vs 38.9%, P = .655); or embolic events (41.7% vs 32.6%, P = .248). Indications for surgery (70.8% vs 70.8%; P = 1) and mortality (13.9% vs 16.7%; P = .741) were similar between groups. Conclusions. SAG endocarditis is an infrequent but serious condition that presents a prognosis similar to that of VGS/SGG.This work was supported by Plan Nacional de I+D+i 2013‐2016 and Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades, Spanish Network for Research in Infectious Diseases (REIPI RD16/0016/0005), co‐financed by the European Development Regional Fund “A way to achieve Europe,” Operative Program Intelligent Growth 2014–2020. We thank CERCA Programme/Generalitat de Catalunya for institutional support. J. M. M. received a personal 80:20 research grant from Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain, during 2017–2021

A Brucella melitensis H38ΔwbkF rough mutant protects against Brucella ovis in rams

Brucella melitensis and Brucella ovis are gram-negative pathogens of sheep that cause severe economic losses and, although B. ovis is non-zoonotic, B. melitensis is the main cause of human brucellosis. B. melitensis carries a smooth (S) lipopolysaccharide (LPS) with an N-formyl-perosamine O-polysaccharide (O-PS) that is absent in the rough LPS of B. ovis. Their control and eradication require vaccination, but B. melitensis Rev 1, the only vaccine available, triggers anti-O-PS antibodies that interfere in the S-brucellae serodiagnosis. Since eradication and serological surveillance of the zoonotic species are priorities, Rev 1 is banned once B. melitensis is eradicated or where it never existed, hampering B. ovis control and eradication. To develop a B. ovis specific vaccine, we investigated three Brucella live vaccine candidates lacking N-formyl-perosamine O-PS: Bov::CAΔwadB (CO2-independent B. ovis with truncated LPS core oligosaccharide); Rev1::wbdRΔwbkC (carrying N-acetylated O-PS); and H38ΔwbkF (B. melitensis rough mutant with intact LPS core). After confirming their attenuation and protection against B. ovis in mice, were tested in rams for efficacy. H38ΔwbkF yielded similar protection to Rev 1 against B. ovis but Bov::CAΔwadB and Rev1::wbdRΔwbkC conferred no or poor protection, respectively. All H38ΔwbkF vaccinated rams developed a protracted antibody response in ELISA and immunoprecipitation B. ovis diagnostic tests. In contrast, all remained negative in Rose Bengal and complement fixation tests used routinely for B. melitensis diagnosis, though some became positive in S-LPS ELISA owing to LPS core epitope reactivity. Thus, H38ΔwbkF is an interesting candidate for the immunoprophylaxis of B. ovis in B. melitensis-free areas.Publishe

Roadmap on spatiotemporal light fields

Spatiotemporal sculpturing of light pulse with ultimately sophisticated structures represents the holy grail of the human everlasting pursue of ultrafast information transmission and processing as well as ultra-intense energy concentration and extraction. It also holds the key to unlock new extraordinary fundamental physical effects. Traditionally, spatiotemporal light pulses are always treated as spatiotemporally separable wave packet as solution of the Maxwell's equations. In the past decade, however, more generalized forms of spatiotemporally nonseparable solution started to emerge with growing importance for their striking physical effects. This roadmap intends to highlight the recent advances in the creation and control of increasingly complex spatiotemporally sculptured pulses, from spatiotemporally separable to complex nonseparable states, with diverse geometric and topological structures, presenting a bird's eye viewpoint on the zoology of spatiotemporal light fields and the outlook of future trends and open challenges.Comment: This is the version of the article before peer review or editing, as submitted by an author to Journal of Optics. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from i

Nueva metodología y recursos online para la adaptación de las prácticas de laboratorio de Óptica a escenarios docentes con diferente grado de presencialidad

Memoria ID-040 Ayudas de la Universidad de Salamanca para la innovación docente, curso 2020-2021