Multiwavelength study of quiescent states of MrK 421 with unprecedented hard x-Ray coverage provided by NuStar in 2013

We present coordinated multiwavelength observations of the bright, nearby BL Lacertae object Mrk 421 taken in 2013 January–March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, VERITAS, and other collaborations and instruments, providing data from radio to very high energy (VHE) γ-ray bands. NuSTAR yielded previously unattainable sensitivity in the 3–79 keV range, revealing that the spectrum softens when the source is dimmer until the X-ray spectral shape saturates into a steep G » 3 power law, with no evidence for an exponential cutoff or additional hard components up "aprox" 80keV. For the first time, we observed both the synchrotron and the inverse-Compton peaks of the spectral energy distribution (SED) simultaneously shifted to frequencies below the typical quiescent state by an order of magnitude. The fractional variability as a function of photon energy shows a double-bump structure that relates to the two bumps of the broadband SED. In each bump, the variability increases with energy, which, in the framework of the synchrotron self-Compton model, implies that the electrons with higher energies are more variable. The measured multi band variability, the significant X-ray-toVHE correlation down to some of the lowest fluxes ever observed in both bands, the lack of correlation between optical/UV and X-ray flux, the low degree of polarization and its significant (random) variations, the short estimated electron cooling time, and the significantly longer variability timescale observed in the NuSTAR light curves point toward in situ electron acceleration and suggest that there are multiple compact regions contributing to the broadband emission of Mrk 421 during low-activity states.

Limits to dark matter annihilation cross-section from a combined analysis of MAGIC and Fermi-LAT observations of dwarf satellite galaxies

We present the first joint analysis of gamma-ray data from the MAGIC Cherenkov telescopes and the Fermi Large Area Telescope (LAT) to search for gamma-ray signals from dark matter annihilation in dwarf satellite galaxies. We combine 158 hours of Segue 1 observations with MAGIC with 6-year observations of 15 dwarf satellite galaxies by the Fermi-LAT. We obtain limits on the annihilation cross-section for dark matter particle masses between 10 GeV and 100 TeV – the widest mass range ever explored by a single gamma-ray analysis. These limits improve on previously published Fermi-LAT and MAGIC results by up to a factor of two at certain masses. Our new inclusive analysis approach is completely generic and can be used to perform a global, sensitivity-optimized dark matter search by combining data from present and future gamma-ray and neutrino detectors.

A contribution on modeling methodologies for multibody systems.

Multibody System Dynamics has been responsible for revolutionizing Mechanical Engineering Design by using mathematical models to simulate and optimize the dynamic behavior of a wide range of mechanical systems. These mathematical models not only can provide valuable informations about a system that could otherwise be obtained only by experiments with prototypes, but also have been responsible for the development of many model-based control systems. This work represents a contribution for dynamic modeling of multibody mechanical systems by developing a novel recursive modular methodology that unifies the main contributions of several Classical Mechanics formalisms. The reason for proposing such a methodology is to motivate the implementation of computational routines for modeling complex multibody mechanical systems without being dependent on closed source software and, consequently, to contribute for the teaching of Multibody System Dynamics in undergraduate and graduate levels. All the theoretical developments are based on and motivated by a critical literature review, leading to a general matrix form of the dynamic equations of motion of a multibody mechanical system (that can be expressed in terms of any set of variables adopted for the description of motions performed by the system, even if such a set includes redundant variables) and to a general recursive methodology for obtaining mathematical models of complex systems given a set of equations describing the dynamics of each of its uncoupled subsystems and another set describing the constraints among these subsystems in the assembled system. This work also includes some discussions on the description of motion (using any possible set of motion variables and admitting any kind of constraint that can be expressed by an invariant), and on the conditions for solving forward and inverse dynamics problems given a mathematical model of a multibody system. Finally, some examples of computational packages based on the novel methodology, along with some case studies, are presented, highlighting the contributions that can be achieved by using the proposed methodology.

Avaliação do erro estático da ferramenta de uma máquina fresadora com arquitetura paralela.

Os mecanismos amplamente utilizados em aplicações industriais são de tipo serial, porém há algum tempo vem sendo desenvolvidos estudos sobre as vantagens que os mecanismos de arquitetura paralela oferecem em contraposição com os seriais. Rigidez, precisão, altas frequências naturais e velocidade são algumas características que os mecanismos paralelos atribuem a máquinas já consolidadas na indústria, destinadas principalmente nas operações de manipulação (pick and place). Nesse sentido, é relevante o estudo sobre a funcionalidade em outros tipos de operação como a usinagem e, particularmente o fresamento. Para isto, devem-se ainda explorar e desenvolver as capacidades dos mecanismos paralelos em relação à rigidez e à precisão nas operações mencionadas. Foi desenvolvido previamente o projeto e montagem do protótipo de uma máquina fresadora de arquitetura paralela. Também aracterizado pela redundância na atuação para o posicionamento da ferramenta. Com este intuito, pretende-se no trabalho atual, avaliar o erro estático de posicionamento da ferramenta por métodos experimentais, quantificar os deslocamentos, realizar um mapeamento experimental em diversas configurações dos membros. Por outro lado, pretende-se adaptar um modelo numérico simplificado que possa prever as deformações elásticas em diversas configurações, que contemple o efeito de juntas lineares flexíveis e que de alguma forma ajude a identificar as principais fontes de erro. Para tal, foram elaboradas rotinas de programação que através da cinemática inversa e o uso do método dos elementos finitos tentem prever o que de fato acontece nos experimentos. Foi proposta também uma implementação alternativa para o controle do mecanismo através de um software CNC e a conversão de coordenadas cartesianas em coordenadas dos atuadores, isto ajudaria na geração do código G. Finalmente, foram elaboradas algumas trajetórias que tentam avaliar a exatidão e repetitividade do mecanismo além de descrever outras trajetórias livres.

Solid Waste Management And Regulations in the Marshall Islands

The Marshall Islands, a small island developing nation, has a significant solid waste problem. The atoll environment of the Majuro, the capital of the Marshall Islands, is one of scarce land and overpopulation. Increasing Western influences has been a major factor in this solid waste problem. This problem has created health issues and is an impediment to the development of a tourism industry, which is essential to the development of economic opportunities. Responsibility for solid waste management in Majuro is divided between several governmental and non-governmental agencies. This system is dysfunctional as there is little or no cooperation between the agencies. Although many consultants have developed recommendations, no action has been taken. Developing an action plan to consolidate solid waste management under one authority is important to solving of this solid waste problem. This project proposes legislation creating a solid waste management authority that will have the power to regulate all aspects of solid waste and help implement education and awareness to the people of the Marshall Islands.

Automatic Fiscal Stabiliser: Make it happen! EPC Discussion Paper, 2 May 2016

The eurozone crisis triggered a whole new series of innovations in EU economic governance in order to make the Union more resilient for the next economic downswing. But one of the more persistent issues are the socio-economic divergences between member states, identified by the Five Presidents’ Report as a major problem in the functioning of the Economic and Monetary Union (EMU). Debates took place in recent years about automatic stabilisers, and more specifically about the possibility of introducing an unemployment insurance within the EMU. While the need for some form of fiscal risk-sharing has become a dominant view in expert circles, there has been much less progress among the main political parties and stakeholders. In this study, Regula Hess and László Andor analyse the political feasibility of the adoption of an automatic fiscal stabiliser (AFS) for the eurozone by evaluating actors’ positions towards three distinctive proposals: 1) cyclical shock insurance, 2) reinsurance, 3) a European basic unemployment insurance; they included an empirical case study of France and Germany as the most relevant players within the intergovernmental bargaining constellation. Although the authors realise the current political context makes the adoption of an AFS improbable, Hess and Andor encourage stakeholders to further pursue the discussion, as windows of opportunities can open at any time, and even give some suggestions on what the parameters of the most feasible proposal might be.

Sulfur isotope rations in oceanic basement samples

Low temperature alteration of oceanic basement rocks is characterized by net gain of sulfur, which commonly yields low d34S values, suggesting involvement of microbial sulfate reduction. In order to test whether secondary sulfide minerals are consistent with a biogenic source, we apply high precision multiple sulfur isotope analysis to bulk rock sulfide and pyrite isolates from two contrasting types of altered oceanic basement rocks, namely serpentinized peridotites and altered basalts. Samples from two peridotite sites (Iberian Margin and Hess Deep) and from a basalt site on the eastern flank of the Juan de Fuca Ridge yield overlapping d34S values ranging from 0 per mil to -44 per mil. In contrast, sulfides in the basalt site are characterized by relatively low D33S values ranging from -0.06 per mil to 0.04 per mil, compared to those from peridotite sites (0.00 per mil to 0.16 per mil). The observed D33S signal is significant considering the analytical precision of 0.014 per mil (2 sigma). We present a batch reaction model that uses observed d34S and D33S relationships to quantify the effect of closed system processes and constrain the isotope enrichment factor intrinsic to sulfate reduction. The estimated enrichment factors as large as 61 per mil and 53 per mil, for peridotite and basalt sites respectively, suggest the involvement of microbial sulfate reduction. The relatively high D33S values in the peridotite sites are due to sulfate reduction in a closed system environment, whereas negative D33S values in the basalt site reflect open system sulfate reduction. A larger extent of sulfate reduction during alteration of peridotite to serpentinite is consistent with its higher H2 production capacity compared to basalt alteration, and further supports in-situ microbial sulfate reduction coupled with H2 production during serpentinization reactions.

(Table 1) Stable-isotopes of mineral separates and whole-rock powders from altered volcanic rocks of DSDP Hole 62-465A

Hess Rise, in the western Pacific Ocean, formed in the mid-Cretaceous south of the equator and moved north with the Pacific Plate (Lancelot and Larson, 1975; Lancelot, 1978; Valuer et al., 1979). Southern Hess Rise was a volcanic archipelago, at least until late Albian time, after which it subsided to become one of the major aseismic rises in the present western Pacific. A second pulse of volcanic activity apparently occurred in the Campanian-Maastrichtian interval, which may be related to tectonic uplift of Hess Rise (Valuer and Jefferson, this volume). Trachytic rocks underlie 412 meters of carbonate sediments at Site 465 on southern Hess Rise. Twenty-four meters of trachyte were recovered from a 64-meter cored interval. The rocks are relatively homogeneous in texture, color, and composition, indicating that the cored sequence was probably part of only one magmatic event (Seifert et al., this volume). Large (> 5-mm) vesicles and oxidized parts of some flows suggest subaerial or shallow-water extrusions. The rocks are high in silica and relatively rich in Na2O, K2O, and light rare-earth elements. The upper part of the volcanic-rock sequence is a breccia, the fragments cemented by calcite, pyrite, and rare barite. Some of the resultant veins are more than 1 cm thick. In addition to the veins, many vesicles are also filled with these minerals. Brecciation and the number and thickness of veins decrease with depth in the hole. The degree of weathering, as indicated by water content, also decreases with depth.