The fragmentation of expanding shells II: Thickness matters

We study analytically the development of gravitational instability in an expanding shell having finite thickness. We consider three models for the radial density profile of the shell: (i) an analytic uniform-density model, (ii) a semi-analytic model obtained by numerical solution of the hydrostatic equilibrium equation, and (iii) a 3D hydrodynamic simulation. We show that all three profiles are in close agreement, and this allows us to use the first model to describe fragments in the radial direction of the shell. We then use non-linear equations describing the time-evolution of a uniform oblate spheroid to derive the growth rates of shell fragments having different sizes. This yields a dispersion relation which depends on the shell thickness, and hence on the pressure confining the shell. We compare this dispersion relation with the dispersion relation obtained using the standard thin-shell analysis, and show that, if the confining pressure is low, only large fragments are unstable. On the other hand, if the confining pressure is high, fragments smaller than predicted by the thin-shell analysis become unstable. Finally, we compare the new dispersion relation with the results of 3D hydrodynamic simulations, and show that the two are in good agreement.Comment: 9 pages, 9 figures, accepted by MNRA

THz-range free-electron laser ESR spectroscopy: techniques and applications in high magnetic fields

The successful use of picosecond-pulse free-electron-laser (FEL) radiation for the continuous-wave THz-range electron spin resonance (ESR) spectroscopy has been demonstrated. The combination of two linac-based FELs (covering the wavelength range of 4 - 250 $\mu$m) with pulsed magnetic fields up to 70 T allows for multi-frequency ESR spectroscopy in a frequency range of 1.2 - 75 THz with a spectral resolution better than 1%. The performance of the spectrometer is illustrated with ESR spectra obtained in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the low-dimensional organic material (C$_6$H$_9$N$_2$)CuCl$_3$.Comment: 9 pages, 9 figures. Rev. Sci. Instrum., accepte

Weak continuous monitoring of a flux qubit using coplanar waveguide resonator

We study a flux qubit in a coplanar waveguide resonator by measuring transmission through the system. In our system with the flux qubit decoupled galvanically from the resonator, the intermediate coupling regime is achieved. In this regime dispersive readout is possible with weak backaction on the qubit. The detailed theoretical analysis and simulations give a good agreement with the experimental data and allow to make the qubit characterization.Comment: 4 pages, 3 figures, to be published in Phys. Rev.

Annual Report 2005 - Institute of Nuclear and Hadron Physics

Preface The Forschungszentrum Rossendorf (FZR) at Dresden is a multidisciplinary research center within the Wissenschafts-Gemeinschaft G. W. Leibniz (WGL), one of the German agencies for extra-university research. The center is active in investigations on the structure of matter as well as in the life sciences and in environmental research. The Institute of Nuclear and Hadron Physics (IKH) within the FZR avails for its research the coupling of radiation to matter in subatomic dimensions as well as to tissue, to cells, and to their components. Its research in the field of Subatomic Physics is part of the FZR-program Structure of Matter and its investigations concerning the interaction of Biostructures and Radiation contribute to the bf Life Science program of the FZR. In this field the IKH exploits possibilities for transfer and introduction of experimental and theoretical techniques from particle and nuclear physics to projects in radiobiology and biophysics. Much of this kind of interdisciplinary transfer is connected to the Radiation Source ELBE at the FZR. With its superconducting accelerator for relativistic electrons this large installation provides photons in the wide wavelength range from fm to mm - i.e. bremsstrahlung for the investigation of photonuclear processes, hard X-rays for radiobiological and other studies and infrared light for research on the structural dynamics of biomolecules. The investigation of radiation-induced processes not only dominates the projects in nuclear astrophysics as pursued at ELBE, it also is a central theme of the experimental and theoretical research performed by the IKH in close connection to the heavy ion synchrotron SIS and the upcoming FAIR facility at Darmstadt. ELBE also will deliver compact bunches of secondary neutrons and fission fragments; both offer new possibilities in laboratory studies related to the cosmic breeding of the chemical elements thus complementing the astrophysics-motivated studies with bremsstrahlung photons..

Recent changes in trends of mortality from cervical cancer in Southeastern Brazil

OBJECTIVE: To analyze the trends of cervical cancer mortality in Brazilian Southeastern states, and to compare them to Brazil and other regions between 1980 and 2020. METHODS: Time series study based on data from the Sistema de Informações de Mortalidade (Brazilian Mortality Information System). Death data were corrected by proportional redistribution of deaths from ill-defined causes and cervical cancer of unspecified portion. Age-standardized and age-specific rates were calculated by screening target (25–39 years; 40–64 years) and non-target (65 years or older) age groups. Annual percentage changes (APC) were estimated by linear regression model with breakpoints. The coverage of Pap Smear exam in the Unified Health System (SUS) was evaluated between 2009 and 2020 according to age group and locality. RESULTS: There were increases in corrected mortality rates both in 1980 and in 2020 in all regions, with most evident increments at the beginning of the series. There was a decrease in mortality nationwide between 1980-2020; however, the state of São Paulo showed a discrete upward trend in 2014-2020 (APC=1.237; 95%CI 0.046-2.443). Noteworthy is the trend increment in the 25–39 year-old group in all study localities, being sharper in the Southeast region in 2013-2020 (APC=5.072; 95%CI 3.971-6.185). Screening coverage rates were highest in São Paulo and lowest in Rio de Janeiro, with a consistent decline from 2012 onwards at all ages. CONCLUSIONS: São Paulo is the first Brazilian state to show a reversal trend in mortality from cervical cancer. The changes in mortality patterns identified in this study point to the need for reorganization of the current screening program, which should be improved to ensure high coverage, quality, and adequate follow-up of all women with altered test results.OBJETIVO: Analisar as tendências da mortalidade por câncer de colo de útero nos estados da região Sudeste e compará-las com o Brasil e demais regiões entre 1980 e 2020. MÉTODOS: Estudo de série temporal com base nos dados do Sistema de Informações de Mortalidade. Os dados de óbito foram corrigidos por redistribuição proporcional das mortes por causas mal definidas e por câncer de útero de porção não especificada. Foram calculadas taxas padronizadas por idade e específicas por faixas etárias alvo de rastreamento (25–39 anos; 40–64 anos) e não alvo (65 anos ou mais). Variações percentuais anuais foram estimadas por modelo de regressão linear com pontos de quebra. A cobertura do exame Papanicolau no Sistema Único de Saúde (SUS) foi avaliada entre 2009 e 2020 segundo faixa etária e localidade. RESULTADOS: Foram verificados aumentos das taxas de mortalidade corrigidas tanto em 1980 como em 2020 em todas as regiões, com incrementos mais evidentes no início da série. Houve queda da mortalidade em todo o país entre 1980-2020, entretanto, o estado de São Paulo apresentou discreta tendência de aumento em 2014-2020 (APC=1,237; IC95% 0,046–2,443). Destaca-se o incremento da tendência no grupo de 25–39 anos em todas as localidades de estudo, mostrando-se mais acentuado na região Sudeste em 2013–2020 (APC=5,072; IC95% 3,971–6,185). As taxas de cobertura de rastreamento foram mais elevadas em São Paulo e mais baixas no Rio de Janeiro, com queda consistente a partir de 2012 em todas as idades. CONCLUSÕES: São Paulo é o primeiro estado brasileiro a apresentar inversão de tendência da mortalidade por câncer de colo do útero. As mudanças nos padrões de mortalidade identificadas neste estudo apontam para a necessidade de reorganização do atual programa de rastreamento, que deve ser aperfeiçoado para garantir alta cobertura, qualidade e seguimento adequado de todas as mulheres com exames alterados

Ionisation-induced star formation III: Effects of external triggering on the IMF in clusters

We report on Smoothed Particle Hydrodynamics (SPH) simulations of the impact on a turbulent $\sim2\times10^{3}$ M$_{\odot}$ star--forming molecular cloud of irradiation by an external source of ionizing photons. We find that the ionizing radiation has a significant effect on the gas morphology, but a less important role in triggering stars. The rate and morphology of star formation are largely governed by the structure in the gas generated by the turbulent velocity field, and feedback has no discernible effect on the stellar initial mass function. Although many young stars are to be found in dense gas located near an ionization front, most of these objects also form when feedback is absent. Ionization has a stronger effect in diffuse regions of the cloud by sweeping up low--density gas that would not otherwise form stars into gravitationally--unstable clumps. However, even in these regions, dynamical interactions between the stars rapidly erase the correlations between their positions and velocities and that of the ionization front.Comment: 12 pages, 16 figures (some downgraded to fit on astro-ph), accepted for publication in MNRA

Performance and quality of service of data and video movement over a 100 Gbps testbed

AbstractDigital instruments and simulations are creating an ever-increasing amount of data. The need for institutions to acquire these data and transfer them for analysis, visualization, and archiving is growing as well. In parallel, networking technology is evolving, but at a much slower rate than our ability to create and store data. Single fiber 100 Gbps networking solutions have recently been deployed as national infrastructure. This article describes our experiences with data movement and video conferencing across a networking testbed, using the first commercially available single fiber 100 Gbps technology. The testbed is unique in its ability to be configured for a total length of 60, 200, or 400 km, allowing for tests with varying network latency. We performed low-level TCP tests and were able to use more than 99.9% of the theoretical available bandwidth with minimal tuning efforts. We used the Lustre file system to simulate how end users would interact with a remote file system over such a high performance link. We were able to use 94.4% of the theoretical available bandwidth with a standard file system benchmark, essentially saturating the wide area network. Finally, we performed tests with H.323 video conferencing hardware and quality of service (QoS) settings, showing that the link can reliably carry a full high-definition stream. Overall, we demonstrated the practicality of 100 Gbps networking and Lustre as excellent tools for data management

Análisis de QTLs para azúcares simples en cerezo

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