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Pair-instability supernovae (PISNe) are thermonuclear explosions of very massive stars. The stellar core needs to be heavier than about 60 Msun for stars to be PISNe. Mass loss prevents massive stars from making large enough cores to be PISNe, and PISNe are presumed to exist in metal-free or metal-poor environment where radiation-driven mass loss is small. Stellar evolution models show that such PISN progenitors evolve to red supergiants (RSGs) shortly before their explosions. However, RSGs are suggested to be pulsationally unstable, and they can experience huge mass loss driven by the pulsation. We investigate the effect of the pulsation-driven mass loss on PISN progenitors. We find that hydrogen-rich layers of PISN progenitors are significantly reduced by the pulsation-driven mass loss, even if they are initially metal-free. Because the pulsation-driven mass loss terminates when the hydrogen-rich envelope is lost, the core mass is not affected by the pulsation-driven mass loss and they still explode as PISNe. However, the large pulsation-driven mass loss can significantly alter observational properties of PISNe.

The question of whether or not the neutrino is a Majorana particle and, if so, what is its average mass remains one of the most fundamental problems in physics today.
The average neutrino mass can be obtained from neutrinoless double beta decay.
The inverse half-life for this process is given by the product of a phase space factor (PSF), a nuclear matrix element (NME) and whatever physics there is beyond the standard model. In this talk, the theory of double beta decay, both with and without the emission of neutrinos, will be rviewed, and recent calculations of the PSF and NME will be presented. From these and from experimental limits on the half-life of neutrinoless double beta decay, one can extract limits on the neutrino mass, both for the exchange of light (m>1MeV) and heavy (m

Alexander Borst aims at understanding the foundations of information processing at the level of small neural circuits, focusing on the visual course control system in Drosophila. Borst’s lab uses a comprehensive approach , combining electron microscopy-aided anatomical reconstructions of the circuit, physiological characterization by both imaging and whole cell patch recordings, genetic circuit manipulation in behaving flies, computational modeling and last but not least, engineering of fly-inspired robots that implement the theoretical principles and test their functionality.
Borst’s outstanding research has yielded a very precise and detailed description of the circuit at the single cell resolution as well as a thorough understanding of the computations it performs.
Several of his major scientific contributions include the discovery that the direction of visually perceived motion is calculated following the Reichardt Model (Single & Borst, Science 1998), the separation of visual information in the fly brain into ON- and OFF-channels, similar to bipolar cells in the retina of vertebrate eyes (Jösch, Schnell, Raghu, Reiff & Borst, Nature 2010) and the existence of four types of neurons in each channel, tuned to one of the four cardinal directions (right, left, up, down) that project into four separate neuronal layers based on their preferred direction (Maisak et al, Nature 2013).

https://www.neuro.mpg.de/borst

An instance of the E2-Lin(2) problem is a system of equations of the form "x_i x_j = b (mod 2)". Given such a system in which it is possible to satisfy all but an epsilon fraction of the equations, we would like to find an assignment that violates as few equations as possible. In this paper, we show that it is NP-hard to satisfy all but a C*epsilon fraction of the equations, for any C < 11/8 and 0 < epsilon

Alexander Borst aims at understanding the foundations of information processing at the level of small neural circuits, focusing on the visual course control system in Drosophila. Borst&#8217;s lab uses a comprehensive approach , combining electron microscopy-aided anatomical reconstructions of the circuit, physiological characterization by both imaging and whole cell patch recordings, genetic circuit manipulation in behaving flies, computational modeling and last but not least, engineering of fly-inspired robots that implement the theoretical principles and test their functionality.
Borst&#8217;s outstanding research has yielded a very precise and detailed description of the circuit at the single cell resolution as well as a thorough understanding of the computations it performs.
Several of his major scientific contributions include the discovery that the direction of visually perceived motion is calculated following the Reichardt Model (Single & Borst, Science 1998), the separation of visual information in the fly brain into ON- and OFF-channels, similar to bipolar cells in the retina of vertebrate eyes (J&ouml;sch, Schnell, Raghu, Reiff & Borst, Nature 2010) and the existence of four types of neurons in each channel, tuned to one of the four cardinal directions (right, left, up, down) that project into four separate neuronal layers based on their preferred direction (Maisak et al, Nature 2013).

https://www.neuro.mpg.de/borst