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We report on ion emission from plasma produced on thick targets irradiated with nanosecond and femtosecond pulses delivered by mid-ultraviolet and soft x-ray lasers, respectively. To distinguish between different ion acceleration mechanisms, the maximum kinetic energy of ions produced under different interaction conditions is plotted versus laser fluence. The transformation of the time-of-flight detector signal into ion charge density distance-of-flight spectra makes it possible to determine the mean kinetic energy of the fastest ion groups based on the influence of the acoustic velocity of ion expansion. This allows obtaining additional characteristics of the ion production. The final energy of the group of fast ions determined using the ion sound velocity model is an order of magnitude larger in the fs-XFEL interaction than in the ns-UV one. On the contrary, the ablation yield of ions in our experiment is seven orders of magnitude greater when applying ns-UV laser pulses, not only due to higher energies of UV laser pulses, but also due to a significant difference in interaction and ion formation mechanisms.

In this presentation we provide an overview of the commissioning and first user experiment of ReLaX in combination with the XFEL beam. We will introduce the setup and laser parameters. We will show the established standard setup combining small-angle x-ray scattering (SAXS), phase-contrast imaging (PCI) and spectroscopy techniques. Finally we will show examples of the data obtained in the interaction of the ReLaX laser with targets of interested for the short-pulse laser community.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2021-10-21T01:27:01Z No. of bitstreams: 1 2019 - M?rio Tatsuo Makita.pdf: 2187775 bytes, checksum: 7b8cf85e0d95bbcd22202fe1bb5710ed (MD5) Made available in DSpace on 2021-10-21T01:27:01Z (GMT). No. of bitstreams: 1 2019 - M?rio Tatsuo Makita.pdf: 2187775 bytes, checksum: 7b8cf85e0d95bbcd22202fe1bb5710ed (MD5) Previous issue date: 2019-04-25 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior The genus Malassezia currently comprises 18 species of lipophilic and lipiddependent yeasts. Although regarded as a normal part of the skin microbiota of warmblooded vertebrates, including humans, these may also become opportunistic agents in dermatitis and otitis. Fungal otitis in dogs has traditionally been associated with M. pachydermatis, even though lipid-dependent species are commonly found frequently resulting in misdiagnosis. In the veterinary clinical routine, microscopy of otological samples is used as an auxiliary tool towards the implementation of adequate drug therapies. The aim of this work was the isolation of Malassezia spp. from otitis samples from dogs and cats, their respective identification to species level, observe the presence of Malassezia in pure and/or co-infections, in vitro assessment of the main virulence factors being produced, which are inherent to the genus pathogenicity and the establishment of a correlation between the detected virulence factors and the nature of the infection. A total of 170 samples from the external ear canal of 94 dogs and 11 cats with clinical otitis were sent to the Laborat?rio de Leveduras Patog?nicas e Ambientais - UFRRJ, where they were inoculated in Modified Dixon Agar and Sabouraud Dextrose 2% Agar supplemented with chloramphenicol. Classical methods allowed for the phenotypic identification, as recommended by Kurtzman et al. (2011) further corroborated through proteomic analysis by MALDI-TOF MS and biochemical analysis by VITEK? 2. For virulence analysis, protease, phospholipase, lipase, esterase and hemolysin production were tested. Of the 105 animals, 63% (66) individuals were positive for Malassezia spp., as one lipid dependent, and 37% (39) were negative for the genus. The positive and negative predictive values of the direct exam were 75.58% and 67.19%, respectively. The sensitivity of the isolation test was 75.58% and the specificity 67.19%. There was no significant difference between yeast recovery in Sabouraud Dextrose 2% Agar and Modified Dixon Agar. The identification by mass spectrophotometry had an 82% accuracy in the identification of the isolates and remaining isolates did not reach the identification score, whereas VITEK? 2 misidentified all the samples. For the enzymatic tests, 100% (96) of the samples were positive for the production of proteases and lipases. Only one sample did not produce neither phospholipase nor esterase. 89% (86) samples were hemolysin producers. It was possible to conclude that the use of Modified Dixon Agar is important in the laboratory routine for microbiological diagnosis of canine and feline otitis, extending the range of Malassezia species diagnosed. Direct microscopic examination proved to be a good indicator of the presence of yeast, but not enlightening regarding its involvement in the infection. In addition, these yeasts have high enzymatic activity in vitro which may be relevant to the pathogenesis of microbial otitis, even when the yeast is not the main pathological agent, as in co-infection otitis, even with low isolation counts. O g?nero Malassezia compreende 18 esp?cies de leveduras lipof?licas e lipodependentes, componentes naturais da microbiota da pele dos animais endot?rmicos, incluindo humanos, e conhecido agente oportunista em dermatites e otites. A maior parte da casu?stica de otite f?ngica em c?es ? atribu?da a M. pachydermatis, mas esp?cies lipodependentes tamb?m podem ser agentes desta afec??o, sendo poss?vel a ocorr?ncia de subdiagn?sticos. Na rotina cl?nica veterin?ria, ? comum o uso do exame direto de amostras otol?gicas como ferramenta auxiliar para direcionar uma melhor conduta terap?utica. Tendo os pontos mencionados em vista, o trabalho objetiva realizar isolamento de Malassezia spp. a partir de amostras de cer?men de c?es e gatos com otite, identificando-as a n?vel de esp?cie, observar a presen?a da Malassezia em infec??es otol?gicas mistas ou puras, verificar in vitro a produ??o dos principais fatores de virul?ncia inerentes ? patogenicidade e correlacionar esses resultados com a natureza da infec??o. Foram utilizadas 170 amostras oriundas dos condutos auditivos externos de 94 c?es e 11 gatos com otite cl?nica, encaminhadas ao Laborat?rio de Leveduras Patog?nicas e Ambientais da UFRRJ, onde foram semeadas nos meios Agar Dixon Modificado e Agar Sabouraud Dextrose 2% com Cloranfenicol. Foram realizados testes cl?ssicos para identifica??o fenot?pica, como preconizado por Kurtzman et al. (2011), an?lise prote?mica por MALDI-TOF MS e bioqu?mico por VITEK? 2 para confirma??o da identifica??o. Para an?lise da virul?ncia foram testadas as produ??es de proteases, fosfolipase, lipases, esterases e hemolisina. Dos 105 animais, 63% (66) animais possuiam Malassezia spp. nas suas amostras, sendo uma delas lipodependente, e 37% (39) n?o tinham a levedura. O valor preditivo positivo e negativo do exame direto foi de 75,58 e 67,19%, respectivamente. A sensibilidade do exame em rela??o ao isolamento foi de 75,58% e 67,19% de especificidade. N?o houve diferen?a significativa entre a recupera??o das leveduras no diagn?stico em Agar Sabouraud Dextrose 2% e Agar Dixon Modificado. Na identifica??o por espectrofotometria de massa obteve-se 82% de acur?cia na identifica??o dos isolados, n?o havendo scores m?nimos de identifica??o para as restantes. O VITEK? 2, identificou erroneamente as amostras analis?das. Para os testes enzim?ticos, 100% (96) das amostras foram positivas para a produ??o de proteases e lipases. Apenas uma amostra n?o foi produtora de fosfolipase e esterase. 89% (86) das amostras foram positivas para a produ??o de hemolisina. Percebe-se que a utiliza??o do Agar Dixon Modificado ? importante na rotina laboratorial de diagn?stico microbiol?gico de otites canina e felina, para ampliar a gama de esp?cies de Malassezia diagnosticadas. O exame direto, realizado no laborat?rio, mostrou ser um bom indicador para a presen?a da levedura, mas n?o necessariamente para indicar seu envolvimento na infec??o. Conclui-se que n?o h? diferen?a entre o uso de ASD e ADM no diagn?stico laboratorial da Malassezia. Al?m disso, essas leveduras possuem alta atividade enzim?tica in vitro, possivelmente integrando a patog?nese da otite microbiana, mesmo quando n?o aparentam ser o principal agente envolvido, como nos casos de otites mistas, incluindo os casos comb baixas contagens no isolamento.

Facebook Intrusion is positively related to distress and negatively with satisfaction with relation. The relation between Facebook Intrusion and flourishing was fully mediated by satisfaction with relation and distress. Moreover, age and sex moderated this mediation. In persons under 20 years of age, Facebook intrusion does not affect satisfaction with relation, but the negative relationship between these variables increased with age. Gender was the moderator of the relationship (a) between satisfaction with relation and flourishing, and (b) between distress and flourishing, namely in men the influence of Facebook intrusion on flourishing was stronger through satisfaction with relation than in women, while in women this influence is stronger through distress than in men.

High energy density physics 32, 63 - 69 (2019). doi:10.1016/j.hedp.2019.05.002, We present results from the SPring-8 Angstrom Compact free electron LAser (SACLA) X-ray free electron laser (XFEL) facility, using an X-ray pump, X-ray probe scheme to observe ultrafast changes in the structure of heated graphite. The 9.8 keV XFEL beam was focused to give an intensity on the order of ∼ 10$^{19}$ W/cm$^2$, and the evolution of the diffraction pattern observed up to delays of 300 fs. The interplanar diffraction peaks weaken significantly within 10s of femtoseconds, but in-plane diffraction orders i.e. those with Miller Index $(hk0)$, persist up to 300 fs, with the observed signal increasing. We interpret this as nonthermal damage through the breaking of interplanar bonds, which at longer timescales leads to ablation by removal of intact graphite sheets. Post-experiment examination of the graphite samples shows damage which is comparable in size to the range of the excited photoelectrons. These results highlight the challenges of accurately modelling X-ray driven heating, as it becomes a routine approach to generating high energy density states., Published by Elsevier, Amsterdam [u.a.]

High intensity X-ray Free Electron Lasers (XFEL) are an ideal tool to heat materials directly and isochorically, which can cause them to be modified and damaged irreversibly. During XFEL-matter interactions, the energy of an XFEL beam will be mainly absorbed by photoionization, creating numerous high-energy photo- and Auger electrons. Modelling this process is quite complex since both atomic physics and plasma physics are involved. Atomic collisional-radiative (CR) codes such as FLYCHK are widely used to simulate such processes. However, the CR codes typically assume local thermodynamic equilibrium (LTE) and are limited to zero dimension. In order to understand the sample damaging mechanisms, we performed two-dimensional kinetic particle-in-cell simulations with radiation transport (PIC-RT) to retrieve the temporal processes of XFEL-matter interactions. The dynamics of XFEL-Matter interactions can roughly divide into three different time scales: 1) electron heating and photoionization by XFEL in ~ 10 fs ; 2) collisional heating and ionization by high-energy photo- and Auger electrons with several keV energy in tens of fs to sub-ps; and 3) collective hydrodynamic explosion driven by ~ TPa thermal pressure from ~100 fs to nanoseconds. The simulation results are compared to our recent experiment that a variety of samples were irradiated by Japanese XFEL SACLA with intensities on the order of 10^20 W/cm^2. The post-analysis of the irradiated samples showed that large holes with radius sizes more than one order of magnitude higher than the XFEL spot were created for metallic samples. The hole size is also much larger than the stopping range of high energy electrons. According to our PIC-RT simulations, we attribute the generation of such large holes to the micro-explosion process. Kinect simulation of the hole generation with multiple time scales is also useful and complementary to understand the change of X-Ray diffraction pattern in the experiment that infers significant material structural change on femtosecond timescales.

SwissFEL requires the monitoring of the photon spectral distribution at a repetition rate of 100 Hz for machine optimization and experiment online diagnostics. The Photon Single Shot Spectrometer has been designed for the photon energy range of 4 keV to 12 keV provided by the Aramis beamline. It is capable of measuring the spectrum in a non-destructive manner, with an energy resolution of Δ E/E = (2-5) × 10-5 over a bandwidth of 0.5% on a shot-to-shot basis. This article gives a detailed description about the technical challenges, structures, and considerations when building such a device, and to further enhance the performance of the spectrometer.