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A presença de enteroparasitoses em crianças em idade pré-escolar tem sido motivo de preocupação pelos órgãos de saúde principalmente devido ao impacto negativo sobre o crescimento e desenvolvimento intelectual dessas crianças. As infecções por parasitas intestinais podem levar a quadros de desnutrição e formas de gastroenterite crônica. O presente trabalho analisou crianças em idade pré-escolar frequentadoras de 11 unidades CMEIs (Centros Municipais de Educação Infantil) na cidade de Guarapuava-PR em 11 unidades. Foram estudadas 287 crianças e o índice de positividade para enteroparasitoses foi de 13,9%. A idade média das 287 crianças foi de 2,7 anos e a maioria das crianças analisadas foram domicialiadas em zona urbana 84,3% e somente 15,7% em zona rural, com média de filhos por família de 2,08 membros. A prevalência das parasitoses mostrou que G. duodenalis foi o protozoário mais isolado com 70,4%, seguido de Ascaris lumbricoides 6,8% o único helminto encontrado. Com relação à terapêutica empregada 20% das crianças tratadas com o fármaco albendazol continuaram apresentando exames positivos para os mesmos parasitas. Já com o fármaco benzoilmetronidazol todas as crianças apresentaram resultados negativos para presença de parasitas nas fezes. Os fatores de risco para enteroparasitoses indicaram que a presença da variável água tratada foi menor nos casos positivos. Nossos resultados mostraram que G. duodenalis foi o parasita mais isolado em crianças em idade pré-escolar.

Do governments strategically choose debt maturity to fill supply gaps across maturities? Building on a new panel data set of more than 9,000 individual Eurozone government debt issues between 1999 and 2015, I find that governments increase long-term debt issues following periods of low aggregate Eurozone long-term debt issuance, and vice versa. This gap-filling behavior is more pronounced for (1) less financially constrained and (2) higher rated governments. Using the ECB's three-year LTRO in 2011-2012 as an event study, I find that core governments filled the supply gap of longer maturity debt, which resulted from peripheral governments accommodating banks' short-term debt demand for "carry trades". This gap-filling implies that governments act as macro-liquidity providers across maturities, thereby adding significant risk absorption capacity to government bond markets.

We demonstrate a compact and robust Yb-fiber master-oscillator power-amplifier system operating at 1018 nm with 2.5-nm bandwidth and 1-ns stretched pulse duration. It produces 87-W average power and 4.9-μJ pulse energy, constituting a powerful seed source for cryogenically cooled ultrafast Yb: yttrium lithium fluoride (Yb:YLF) amplifiers.

How does the organizational form of loan syndicates evolve and what are the effects on price collusion? We develop a novel measure of distance in lending expertise among syndicate lenders, and relate this novel measure to the organizational form of loan syndicates and loan pricing. Studying the U.S. syndicated loan market from 1989 to 2017, we find that the organizational form of loan syndicates significantly varies across our lender measure based on similar specializations in lending which we call syndicated distance. Large lead arrangers prefer to form close and concentrated syndicates by letting lenders with similar lending expertise into their syndicates and allocating those lenders higher loan shares. Analyzing loan pricing, we find that concentrated syndicates possess improved screening abilities, but collude on loan pricing. Consistent with Hatfield et al. (2017), we find however that price collusion of concentrated syndicates only occurs during periods of low market concentration. Our findings imply that both the organizational form of loan syndicates and the level of market concentration affect price collusion.

Doppler laser cooling is a technique to reduce the longitudinal momentum spread of an ion beam in a circular accelerator. In the past, the principle was investigated and verified on non-relativistic ion beams. Within the FAIR project, laser cooling will be applied to high intensity and relativistic ion beams for the first time. Laser cooling results in a further increase of the longitudinal ion density and creates exotic longitudinal phase space distributions. In order to ensure stable operation and optimize the cooling process, this dissertation numerically investigates the particle dynamics and the interplay of the laser force and high intensity effects. This work describes the ion-photon interaction and derives the laser force on ions at relativistic energies. The force is calculated for continuous wave and pulsed laser excitations. The pulsed laser excitation results in a broadband force, which interacts with all ions simultaneously, whereas the width of the continuous wave laser force is typically three to four orders of magnitude smaller. In order to interact with all ions, the position of the continuous wave laser force is scanned during the cooling process. The particle dynamics during the cooling processes for both laser forces are analyzed and compared. The impact of heating effects during the laser cooling process is also investigated. Scattering events within the beams limit the maximum ion intensity for the cooling for both a continuous wave or a pulsed laser system. In addition, numerical simulations show two instabilities, that arise during the scan of the continuous wave laser force and are triggered by space charge. This work describes the development of the instabilities and the impact on the laser cooling process. Analytical expressions for the threshold of instabilities and maximum ion intensities are given. The scaling of the cooling process and intensity limitations with beam energy is discussed in order to evaluate the prospects of laser cooling experiments at relativistic energies. The work concludes with the comparison of the cooling process of non-relativistic carbon ions and relativistic titanium ions. The comparison emphasizes the main challenges for laser cooling experiments in the SIS100 synchrotron at FAIR.

Promoting the stability of the financial system is considered to be a key objective by politicians, policy makers and regulators to support worldwide economic development (e.g., ECB (2007), World Bank (2013)). Understanding that the portfolio choice of financial intermediaries and sovereigns plays an important role resulted in various pieces of regulation and guidelines with the aim to promote the stability of individual institutions and the financial system as a whole (e.g. BIS (2010), IMF and World Bank (2014)). However, the global financial crisis of 2007-2009 and the European sovereign debt crisis of 2010-2012 demonstrated that it still eludes us how this objective can be achieved. The global financial crisis demonstrated how quickly risks can spread across highly interconnected financial institutions causing a global systemic crisis and worldwide economic downturn. One important factor of these risk spillovers among financial institutions is commonality in asset holdings (e.g., Shleifer and Vishny (1992, 2011), Kiyotaki and Moore (1997)). In addition, the European sovereign debt crisis highlighted that the health of financial institutions and sovereigns are intertwined and that sovereign instability can be an important source of risk to the financial system (e.g., Laeven (forthcoming)). One important factor of sovereign instability is the maturity structure of sovereign debt, which affects sovereigns’ exposure to rising funding costs and exclusions from financial markets.

The coastal marine ecosystem near the Elwha River was altered by a massive sediment influx-over 10 million tonnes-during the staged three-year removal of two hydropower dams. We used time series of bathymetry, substrate grain size, remotely sensed turbidity, scuba dive surveys, and towed video observations collected before and during dam removal to assess responses of the nearshore subtidal community (3 m to 17 m depth). Biological changes were primarily driven by sediment deposition and elevated suspended sediment concentrations. Macroalgae, predominantly kelp and foliose red algae, were abundant before dam removal with combined cover levels greater than 50%. Where persistent sediment deposits formed, macroalgae decreased greatly or were eliminated. In areas lacking deposition, macroalgae cover decreased inversely to suspended sediment concentration, suggesting impacts from light reduction or scour. Densities of most invertebrate and fish taxa decreased in areas with persistent sediment deposition; however, bivalve densities increased where mud deposited over sand, and flatfish and Pacific sand lance densities increased where sand deposited over gravel. In areas without sediment deposition, most invertebrate and fish taxa were unaffected by increased suspended sediment or the loss of algae cover associated with it; however, densities of tubeworms and flatfish, and primary cover of sessile invertebrates increased suggesting benefits of increased particulate matter or relaxed competition with macroalgae for space. As dam removal neared completion, we saw evidence of macroalgal recovery that likely owed to water column clearing, indicating that long-term recovery from dam removal effects may be starting. Our results are relevant to future dam removal projects in coastal areas and more generally to understanding effects of increased sedimentation on nearshore subtidal benthic communities.

Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of mud, sand, and gravel since 1927, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams, initiated in September 2011, induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the geomorphic response of a coastal delta to these increases. Detailed measurements of beach topography and nearshore bathymetry show that ~ 2.5 million m3 of sediment was deposited during the first two years of dam removal, which is ~ 100 times greater than deposition rates measured prior to dam removal. The majority of the deposit was located in the intertidal and shallow subtidal region immediately offshore of the river mouth and was composed of sand and gravel. Additional areas of deposition include a secondary sandy deposit to the east of the river mouth and a muddy deposit west of the mouth. A comparison with fluvial sediment fluxes suggests that ~ 70% of the sand and gravel and ~ 6% of the mud supplied by the river was found in the survey area (within about 2 km of the mouth). A hydrodynamic and sediment transport model, validated with in-situ measurements, shows that tidal currents interacting with the larger relict submarine delta help disperse fine sediment large distances east and west of the river mouth. The model also suggests that waves and currents erode the primary deposit located near the river mouth and transport sandy sediment eastward to form the secondary deposit. Though most of the substrate of the larger relict submarine delta was unchanged during the first two years of dam removal, portions of the seafloor close to the river mouth became finer, modifying habitats for biological communities. These results show that river restoration, like natural changes in river sediment supply, can result in rapid and substantial coastal geomorphological responses.

During the last decades femtosecond lasers have proven their vast benefit in both scientific and technological tasks. Nevertheless, one laser feature bearing the tremendous potential for high-field applications, delivering extremely high peak and average powers simultaneously, is still not accessible. This is the performance regime several upcoming applications such as laser particle acceleration require, and therefore, challenge laser technology to the fullest. On the one hand, some state-of-the-art canonical bulk amplifier systems provide pulse peak powers in the range of multi-terawatt to petawatt. On the other hand, concepts for advanced solid-state-lasers, specifically thin disk, slab or fiber systems have shown their capability of emitting high average powers in the kilowatt range with a high wall-plug-efficiency while maintaining an excellent spatial and temporal quality of the output beam. In this article, a brief introduction to a concept for a compact laser system capable of simultaneously providing high peak and average powers all along with a high wall-plug efficiency will be given. The concept relies on the stacking of a pulse train emitted from a high-repetitive femtosecond laser system in a passive enhancement cavity, also referred to as temporal coherent combining. In this manner, the repetition rate is decreased in favor of a pulse energy enhancement by the same factor while the average power is almost preserved. The key challenge of this concept is a fast, purely reflective switching element that allows for the dumping of the enhanced pulse out of the cavity. Addressing this challenge could, for the first time, allow for the highly efficient extraction of joule-class pulses at megawatt average power levels and thus lead to a whole new area of applications for ultra-fast laser systems.

The coherent combination of ultra short laser pulses is a promising approach for scaling the average and peak power of ultrafast lasers. Fiber lasers and amplifiers are especially suited for this technique due to their simple singe-pass setups that can be easily parallelized. Here we propose the combination of the well-known approach of spatially separated amplification with the technique of divided-pulse amplification, i.e. an additionally performed temporally separated amplification. With the help of this multidimensional pulse stacking, laser systems come into reach capable of emitting 10’s of joules of energy at multi-kW average powers that simultaneously employ a manageable number of fibers.

2015 stand der Marburger Grundschule nicht mehr genug Geld zur Verfugung, um ihre Projektwoche zum Thema Gesundheit mit „fertigen Physios“ auf die Beine zu stellen. Da kam die Grundschulleiterin auf die Idee, mit Physioschulern zusammenzuarbeiten. Ein genialer Einfall, wie sich herausstellte.

The ability of laser cooling for relativistic ion beams is investigated. For this purpose, the excitation of relativistic ions with a continuous wave and a pulsed laser is analyzed, utilizing the optical Bloch equations. The laser cooling force is derived in detail and its scaling with the relativistic factor γ is discussed. The cooling processes with a continuous wave and a pulsed laser system are investigated. Optimized cooling scenarios and times are obtained in order to determine the required properties of the laser and the ion beam for the planed experiments. The impact of beam intensity effects, like intrabeam scattering and space charge are analyzed. Predictions from simplified models are compared to particle-in-cell simulations and are found to be in good agreement. Finally two realistic example cases of Carbon ions in the ESR and relativistic Titanium ions in SIS100 are compared in order to discuss prospects for future laser cooling experiments.

In a survey-based study including 42 companies of the chemical B2B industry, the sage and dissemination of Open Innovation (OI) initiatives are investigated. The article focuses on strategies and the motivation to implement OI tools. By summarizing the empirical evidence of OI, the success of projects and perceived satisfaction with the chosen approach is assessed using qualitative comparative analysis (QCA). The results show a very diverse picture of OI approaches in the chemical B2B industry, as only 52% of the participants’ state to use OI at all. However, the potential to use OI for exploration and exploitation purposes is revealed, which is especially of interest for a productive and successful implementation. In addition, the need of top management support to successful implement an OI approach is shown.

High harmonic generation (HHG) of ultrashort laser pulses is a key process for the generation of coherent extreme ultraviolet to soft X-ray radiation, which is routinely employed in a wide variety of applications [1]. Amongst the large variety photoelectron spectroscopy and microscopy particularly demands for high repetition rate and high photon flux sources [2, 3]. As such, fiber laser driven HHG has emerged as a powerful source to provide the highest photon fluxes in combination with unprecedented repetition rates [4].

Sapium belongs to Euphorbiaceae family and comprises 23 species. Sapium glandulosum (L.) Morong is popularly known in Brazil as “pau-leiteiro” and “leitosinha” and it is used in traditional medicine to cicatrisation. Its leaf extracts have shown analgesic, anti-inflammatory and antibacterial activities. The preliminary set of pharmacognostic tools used for quality assessment of medicinal plant parts is macro- and micro-anatomy and S. glandulosum has not anatomical and histochemical description. Thus the aim of this study was to investigate the anatomical and histochemical characteristics of the leaf and stem of S. glandulosum as a means of providing information for quality assessment of herbal industry. The leaves and stems were investigated by employing field emission scanning electron microscopy, light microscopy, and histochemistry techniques. The analysis showed that S. glandulosum had the following anatomical features: dorsiventral and amphistomatic leaves; paracytic stomata; tabular crystal druses; non-articulated and branched laticifers; midrib's biconvex shape with vascular systems in open arc with invaginated ends; petiole with a round shape and slight concavity on the adaxial side; six collateral vascular bundles in U-shaped organisation; a circular stem shape and a sclerenchymatous ring. In the histochemical tests lipophilic components were found in cuticle and in the latex; phenolic compounds were met in the mesophyll and in the latex; starch grains were found in the parenchymatous sheath; lignified elements were met in the sclerenchymatous ring in the cortex and in the perivascular sclerenchymatous caps, beyond in the vessel elements. These features are helpful when conducting a quality control process. Keywords: Druses, Euphorbiaceae, Pau-leiteiro, Pharmacobotanical study, Latex, Quality control

Among other modern imaging techniques, stimulated Raman scattering (SRS) requires an extremely quiet, widely wavelength tunable laser [1], which, up to now, is unheard of in fiber laser systems. Here we present a compact all-fiber laser system, which features an optical parametric oscillator (OPO) based on degenerate four-wave mixing (FWM) in an endlessly single-mode photonic-crystal fiber [2]. We employ pulses from an all-fiber frequency and repetition rate tunable laser, which after amplification and subsequent conversion in the linear OPO cavity arrangement are converted to wavelength ranges of 764–960 nm and 1164–1552 nm at a repetition rate of 9.5 MHz. Thus, all biochemically relevant Raman shifts from 922 to 3322 cm−1 may be addressed in combination with an additional output, which is tunable from 1024 to 1052 nm. This ultra-low-noise output emits synchronized pulses with twice the repetition rate to enable SRS imaging.

Among other modern imaging techniques, stimulated Raman Scattering (SRS) requires an extremely quiet, widely wavelength tunable laser, which, up to now, is unheard of in fiber laser systems. We present a compact all-fiber laser system, which features an optical parametric oscillator (OPO) based on degenerate four-wave mixing (FWM) in an endlessly single-mode photonic-crystal fiber. We employ an all-fiber frequency and repetition rate tunable laser in order to enable wideband conversion in the linear OPO cavity arrangement, the signal and idler radiation can be tuned between 764 and 960 nm and 1164 and 1552 nm at 9.5 MHz. Thus, all biochemically relevant Raman shifts between 922 and 3322 cm-1 may be addressed in combination with a secondary output, which is tunable between 1024 and 1052 nm. This ultra-low noise output emits synchronized pulses with twice the repetition rate to enable SRS imaging. We measure the relative intensity noise of this output beam at 9.5 MHz to be between -145 and -148 dBc, which is low enough to enable high-speed SRS imaging with a good signal-to-noise ratio. The laser system is computer controlled to access a certain energy differences within one second. Combining FWM based conversion, with all-fiber Yb-based fiber lasers enables the construction of the first automated, turn-key and widely tunable fiber laser. This laser concept could be the missing piece to establish CRS imaging as a reliable guiding tool for clinical diagnostics and surgical guidance.