JEERP: Energy Aware Enterprise Resource Planning

Ever increasing energy costs, and saving requirements, especially in enterprise contexts, are pushing the limits of Enterprise Resource Planning to better account energy, with component-level asset granularity. Using an application-oriented approach we discuss the different aspects involved in designing Energy Aware ERPs and we show a prototypical open source implementation based on the Dog Domotic Gateway and the Oratio ER

On the Lagrangian formulation of the double copy to cubic order

We investigate the Lagrangian formulation of the double-copy correspondence between gauge theories and gravity, up to the cubic order. Building on the definition of the double-copy field as a convolution of two vectors, we obtain free gravitational Lagrangians as products of two Yang-Mills Lagrangians, in a form amenable to be easily extended to the massive case. We discuss the origin of these results from tensionless strings and show the existence of gauge fixings that mix the two spin-one sectors and lead to an alternative, especially simple, version of the free Lagrangian. We then construct cubic vertices for the full double-copy multiplet, comprising a graviton, a two-form and a scalar particle, by means of the Noether procedure. Both at the free and at the cubic level the result gets uniquely fixed only upon imposing, on top of gauge invariance, a left-right Lorentz symmetry ruling contraction of indices among double-copy fields. Whereas the outcome nicely matches the cubic interactions of $\mathcal{N}=0$ supergravity, including the gauge-invariant coupling between the scalar particle and the two-form, such a twofold Lorentz symmetry seems to conflict with the perturbative reconstruction of space-time geometry.Comment: 28 pages. minor editing, matches published versio

Low-Order Models for Low-Frequency Combustion Instability in Hybrid Rocket Engines

A low-order model for a hybrid rocket engine is proposed to investigate low-frequency combustion instabilities. The present work is based on a one-way coupling between a one-dimensional thermal model to evaluate the unsteady regression rate and a zero-dimensional model which imposes mass conservation inside the rocket chamber. In this way, it is possible to estimate the unsteady pressure level inside the rocket chamber and predict the amplitude of the oscillations. Two different approaches are compared. In the first approach, the Oxidizer-Fuel (OF) ratio is directly computed from the ratio between the fuel and oxidizer mass flow rates. In this way the OF ratio strongly depends on the regression rate oscillations and, as a consequence, the pressure shows large fluctuations. An alternative approach has been investigated by computing the OF ratio from the fuel and oxidizer istantaneous densities. The two approaches are compared on a representative test case

Emission-Driven Hybrid Rocket Engine Optimization for Small Launchers

Hybrid rocket engines are a green alternative to solid rocket motors and may represent a low-cost alternative to kerosene fueled rockets, while granting performance and control features similar to that of typical storable liquid rocket engines. In this work, the design of a three-stage hybrid launcher is optimized by means of a coupled procedure: an evolutionary algorithm optimizes the engine design, whereas an indirect optimization method optimizes the corresponding ascent trajectory. The trajectory integration also provides the vertical emission profiles required for the evaluation of the environmental impact of the launch. The propellants are a paraffin-based wax and liquid oxygen. The vehicle is launched from the ground and uses an electric turbo pump feed system. The initial mass is given (5000 kg) and the insertion of the payload into a 600-km circular, and polar orbit is considered as a reference mission. Clusters of similar hybrid rocket engines, with only few differences, are employed in all stages to reduce the development and operational costs of the launcher. Optimization is carried out with the aim of maximizing the payload mass and then minimizing the overall environmental impact of the launch. The results show that satisfactory performance is achievable also considering rocket polluting emissions: the carbon footprint of the launch can be reduced by one fourth at the cost of a 5-kg payload mass reduction

SERCA is critical to control the Bowditch effect in the heart

The Bowditch effect or staircase phenomenon is the increment or reduction of contractile force when heart rate increases, defined as either a positive or negative staircase. The healthy and failing human heart both show positive or negative staircase, respectively, but the causes of these distinct cardiac responses are unclear. Different experimental approaches indicate that while the level of Ca2+ in the sarcoplasmic reticulum is critical, the molecular mechanisms are unclear. Here, we demonstrate that Drosophila melanogaster shows a negative staircase which is associated to a slight but significant frequency-dependent acceleration of relaxation (FDAR) at the highest stimulation frequencies tested. We further showed that the type of staircase is oppositely modified by two distinct SERCA mutations. The dominant conditional mutation SERCAA617T induced positive staircase and arrhythmia, while SERCAE442K accentuated the negative staircase of wild type. At the stimulation frequencies tested, no significant FDAR could be appreciated in mutant flies. The present results provide evidence that two individual mutations directly modify the type of staircase occurring within the heart and suggest an important role of SERCA in regulating the Bowditch effect.Fil: Balcazar, Dario Emmanuel. Universidad Nacional de La Plata; ArgentinaFil: Regge, María Victoria. Universidad Nacional de La Plata; ArgentinaFil: Santalla, Manuela. Universidad Nacional de La Plata; ArgentinaFil: Behrensmeyer, Anna Kay. Universität Osnabrück;Fil: Achimón, Fernanda. Universität Osnabrück;Fil: Mattiazzi, Ramona Alicia. Universidad Nacional de La Plata; ArgentinaFil: Ferrero, Paola Viviana. Universidad Nacional de La Plata; Argentin

Anemia in the Elderly: not Always what it Seems.

Anemia in the elderly is a common but challenging clinical scenario. Here we the described the case of an elderly women who presented with anemia and elevated inflammation markers. After a complete diagnostic workup a clear etiology of the anemia could not be found and eventually a bone marrow biopsy was performed: she was diagnosed with myelodysplastic syndrome. She responded well to erythropoietin treatment but her inflammation markers remained elevated and a positron emission tomography was eventually performed. It turned out that the patient suffered from giant cell artheritis, and after steroid treatment her anemia completely resolved. Our case outlines that it is necessary to pay particular attention to anemia of chronic inflammation, which could be due to several and often masked conditions. Myelodysplatic syndromes should be considered when other causes have been ruled out, but their diagnosis can be difficult and requires expertise in the field

D3-branes wrapped on a spindle

We construct supersymmetric $AdS_3\times \Sigma$ solutions of minimal gauged supergravity in $D=5$, where $\Sigma$ is a two-dimensional orbifold known as a spindle. Remarkably, these uplift on $S^5$, or more generally on any regular Sasaki-Einstein manifold, to smooth solutions of type IIB supergravity. The solutions are dual to $d=2$, $\mathcal{N}=(0,2)$ SCFTs and we show that the central charge for the gravity solution agrees with a field theory calculation associated with D3-branes wrapped on $\Sigma$. Unlike for smooth $\Sigma$ the superconformal R-symmetry mixes with the $U(1)$ isometry of the spindle.Comment: 6 pages. Minor changes. Matches published versio