Ten thousand times faster: Classifying multidimensional data on a spiking neuromorphic hardware system.

Discrimination of sensory inputs is a computational task that biological neuronal systems perform very efficiently. Assessing the principles in those systems is a promising approach to develop technical solutions for many problems, such as data classification. A particular problem here is to train a classifier in a supervised fashion to discriminate classes in multidimensional data. We implemented a network of spiking neurons that solves this task using a neuromorphic hardware system, that is, analog neuronal circuits on a silicon substrate. This system enables us to do high-performance computation in a biologically inspired way, with spiking neurons as computational units. In this contribution, we illustrate solutions to technical challenges that occur when implementing a classifier on neuromorphic hardware. 

The network topology of the insect olfactory system provides a well suited template for a neuronal architecture processing multidimensional data. In our classifier network, the value of each dimension of a data vector determines the rate of a stochastically generated spike train. The spike trains are fed into non-overlapping populations of neurons. Those populations project onto an association layer with winner-take-all properties representing the output of the classifier. During classifier training, the weights in this projection are adjusted according to a firing-rate based learning rule. 

The values in multidimensional data sets are typically real numbers, but neuronal firing rates are restricted to values between zero and some maximal value. Hence, the data must be transformed into a positive, bounded representation. We achieved this by representing each data point as a vector of distances to a number of points in data space (“virtual receptors” [1]). The representation by virtual receptors inevitably introduces correlation between input dimensions. We reduced this correlation using lateral inhibition in the first neuronal layer, leading to a significant increase in classifier performance. We found that decorrelation was most efficient when we scaled the inhibitory weights according to the correlation between the connected populations. 

We ran our classifier network on a neuromorphic hardware system that runs at ten thousand times the speed of biological neurons, thus suited for high performance computing [2]. However, the considerable variance of rate-response sensitivity across hardware neurons decreased classification performance. We therefore developed a calibration routine to counteract the neuronal variance.

References

[1] Schmuker, M. and Schneider, G. (2007). Processing and classification of chemical data inspired by insect olfaction. Proc. Natl. Acad. Sci. U S A 104, 20285-20289. 
[2] Brüderle, D., Bill, J., Kaplan, B., Kremkow, J., Meier, K., Müller, E. and Schemmel, J. (2010). Simulator-like exploration of cortical network architectures with a mixed-signal VLSi system. In Proc. of IEEE Intern. Symp. on Circuits and Systems (ISCAS), 2784–8787

The Israeli-Palestinian conflict and the politics of the Quartet

The 'Quartet' is an informal diplomatic mechanism designed to coordinate the efforts of major actors within the context of the Israeli-Palestinian conflict. Formed in 2001, the grouping is composed of representatives from the United States, the European Union, Russia and the Office of the UN Secretary General. Existing analysis of the Quartet, especially concerning the capacity of the grouping to facilitate both individual and collective outcomes for its members, is in some respects misleading. This thesis establishes the historical precedents to the formation of the Quartet, and examines the outputs and outcomes of the grouping within the politico-strategic context of the Middle East peace process from 2001-2011. It presents each of the Quartet members as actors, who, while working in support of a peace process between the Israelis and Palestinians, also hoped to advance their national or organisational objectives through the association itself. By examining the interplay between the complimentary and competing agendas and capabilities of the Quartet members, the thesis aims to provide enhanced insight into the role of external parties in the Israeli-Palestinian peace process. Accordingly, it examines the key factors that motivated individual governments and institutions to form the Quartet, and analyses the extent to which the Quartet members had both collective and individual objectives for the grouping. In examining whether these objectives were achieved during the period, the thesis argues that the outcomes of the Quartet were shaped by its internal decision-making processes, the exclusivity of the US-Israel relationship, the nature of the Israeli-Palestinian conflict and the regional contexts in which its members sought collective influence. It argues that the Quartet demonstrated potential as a diplomatic tool, although in practice it had greater utility as a forum for coordination among its members than for influencing the behaviour of the parties to the conflict

Analysis of environmental influences in nuclear half-life measurements exhibiting time-dependent decay rates

In a recent series of papers evidence has been presented for correlations between solar activity and nuclear decay rates. This includes an apparent correlation between Earth-Sun distance and data taken at Brookhaven National Laboratory (BNL), and at the Physikalisch-Technische Bundesanstalt (PTB). Although these correlations could arise from a direct interaction between the decaying nuclei and some particles or fields emanating from the Sun, they could also represent an "environmental" effect arising from a seasonal variation of the sensitivities of the BNL and PTB detectors due to changes in temperature, relative humidity, background radiation, etc. In this paper, we present a detailed analysis of the responses of the detectors actually used in the BNL and PTB experiments, and show that sensitivities to seasonal variations in the respective detectors are likely too small to produce the observed fluctuations

Morbidity and Quality of Life in Bladder Cancer Patients following Cystectomy and Urinary Diversion: A Single-Institution Comparison of Ileal Conduit versus Orthotopic Neobladder

Objective. To evaluate and compare noncontinent and continent urinary diversion after radical cystectomy in patients with bladder cancer. Methods. A total of 301 patients submitted to radical cystectomy at the Charité-University Hospital Berlin from 1993 to 2007 including 146 with an ileal conduit and 115 with an ileal neobladder. Clinical and pathological data as well as oncological outcome were retrospectively analyzed and compared. Quality of life was analyzed using the EORTC QLQ-C30 and BLM30 questionnaires. Results. 69.1% and 69.6% of all patients who received an ileal conduit and ileal neobladder, respectively, developed early complications. The two groups differed significantly concerning the occurrence of postoperative ileus (P = 0.02) favoring patients who received an ileal conduit but not with regard to any other early-onset complication evaluated. Patients with ileal neobladder had a significantly better global health status and quality of life (P = 0.02), better physical functioning (P = 0.02), but also a higher rate of diarrhoea (P = 0.004). Conclusion. Cystectomy with any type of diversion remains a complication-prone surgery. Even if the patient groups are not homogeneous in all respects, there are many arguments in favor of the ileal neobladder as the urinary diversion of choice

Characterization of the amidoxime reducing components ARC1 and ARC2 from Arabidopsis thaliana

Five molybdenum-dependent enzymes are known in eukaryotes. While four of them are under investigation since decades, the most recently discovered, (mitochondrial) amidoxime reducing component ((m)ARC), has only been characterized in mammals and the green algae Chlamydomonas reinhardtii. While mammalian mARCs have been shown to be involved in various signaling pathways, Chlamydomonas ARC was shown to be a nitric oxide (NO)-forming nitrite reductase. Similar to mammals, higher plants possess two ARC proteins. In order to test whether plant ARCs have a similar function in NO production to the function they have in C. reinhardtii, we analyzed the enzymes from the model plant Arabidopsis thaliana. Both ARC1 and ARC2 from Arabidopsis could reduce N-hydroxylated compounds, while nitrite reduction to form NO could only be demonstrated for ARC2. Searching for physiological electron donors we found that both ARC enzymes accept electrons from NADH via cytochrome b5 reductase and cytochrome b5, but only ARC2 is able to accept electrons from nitrate reductase. Furthermore, arc-deficient mutant plants were similar to wildtype plants regarding growth and also nitrite-dependent NO-formation. Altogether, our results did not confirm the hypothesis that either ARC1 or ARC2 are involved in physiologically relevant nitrite-dependent NO-formation. In contrast, our data suggest that ARC1 and ARC2 have distinct, yet unknown physiological roles in higher plants

Mindfulness Training at School: A Way to Engage Adolescents with Sustainable Consumption?

A central challenge in research on education for sustainable consumption (ESC) is to develop new approaches to engage adolescents with sustainable consumption (SC) in a way that addresses not only the cognitive but also the socio-emotional and behavioral levels. Mindfulness-based interventions (MBIs) that foster awareness, (self-)reflection, and ethical values could potentially leverage learning processes in ESC. The present study was the first one to investigate the potential effects of a consumption-specific MBI on sustainable consumption behavior (SCB) in the areas of nutrition and clothing. The eight-week long intervention was carried out with 15-year old adolescents (N = 85) directly at school. A randomized pre-post waitlist control group design with mixed methods was applied. The study revealed the strong effects of the adapted MBI on precursors of SCB and further effects not directly related to but potentially conducive for SCB. Actual behavioral effects were minor. Substantial inter-individual differences and inconsistencies between qualitative and quantitative results imply case-related effects that do not allow generalizable conclusions to be drawn. Nevertheless, the results of this pilot study indicate that combining mindfulness training with ESC formats appears to be a feasible and fruitful approach to engage adolescents with SC. Future practice and research should consider more diverse target groups, other consumption areas, and longer periods for interventions and their evaluation.BMBF, 01UT1416A, Bildung für Nachhaltigen Konsum durch Achtsamkeitstraining - Teilprojekt 1 der TU Berlin: Achtsamkeitsforschung und Nachhaltiger KonsumBMBF, 01UT1416B, Bildung für Nachhaltigen Konsum durch Achtsamkeitstraining - Teilprojekt 2 der Leuphana Universität Lüneburg: Bildung für Nachhaltigen Konsu

Características dos Sistemas de Controle em Fazendas de Soja no Norte de Mato Grosso

Este trabalho investigou os sistemas de controle utilizados nas fazendas de soja no norte de Mato Grosso, a partir da perspectiva dos gestores. Aceitou-se, com base na literatura, que organizações dessa natureza tentem a ser empresas familiares que assumem a configuração de estruturas organizacionais simples. A partir dessa definição, e com base no que a literatura aponta como variáveis estratégicas críticas que agem sobre o agronegócio da soja, foi desenvolvido um questionário de entrevistas que buscou mensurar a medida com que os fazendeiros se preocupam com as mesmas, e mensurar a medida com que eles se preocupam em formalizar procedimentos de controle. As entrevistas foram realizadas por telefone, com 33 fazendeiros de soja em oito municípios da região, durante o mês de maio de 2015. Os dados obtidos apontaram que os fazendeiros tendem a se preocupar consideravelmente com todas as variáveis críticas, sem que haja consenso relevante sobre uma escala de prioridades. Quanto aos processos de formalização, confirmou-se o que a literatura prevê, com os dados apontando que o controle tende a ser centralizado e pouco ou insignificantemente formalizado. Mas os dados ofereceram também a possibilidade de reflexões sobre os respondentes, confrontados com a literatura de antropologia e sociologia disponíveis sobre as comunidades de migrantes da região. Como contribuições, o trabalho aponta caminhos possíveis para investigação de sistemas de controle e de contabilidade em organizações familiares, e estruturas organizacionais simples em geral

Tierschutzindikatoren für die betriebliche Eigenkontrolle – Impulse für die Ökologische Landwirtschaft

Gemäß Tierschutzgesetz müssen Nutztierhalter*innen seit 2014 im Rahmen einer betrieblichen Eigenkontrolle überprüfen, ob sie ihre Herden tiergerecht halten. Eine Möglichkeit dieser Pflicht beizukommen ist die Verwendung der KTBL-Tierschutzindikatoren für Rinder, Geflügel und Schweine. In dem Forschungsvorhaben „EiKoTiGer – Eigenkontrolle Tiergerechtheit“ („Praxistauglichkeit von Tierschutzindikatoren bei der betrieblichen Eigenkontrolle, Erarbeitung eines Orientierungsrahmens sowie technische Umsetzung in digitalen Anwendungen“) wird derzeit bundesweit auf insgesamt 120 Praxisbetrieben (Rind, Schwein und Geflügel) untersucht, ob die ausgewählten und in den KTBL-Leitfäden vorgeschlagenen Tierschutzindikatoren für die betrieblichen Eigenkontrollen praktikabel und sinnvoll einsetzbar sind. Das Ziel des Workshops ist es, mit Vertreter*innen aus Beratung, Praxis und Wissenschaft in einen Dialog zu treten, um gemeinsam den Nutzen und die Verwendbarkeit der Ergebnisse/Erkenntnisse aus dem „EiKoTiGer“-Projekt für die Ökologische Landwirtschaft zu diskutieren. In einem Impulsvortrag werden die Hintergründe, wie z.B. die Entstehungsgeschichte der KTBL-Tierschutzindikatoren-Leitfäden erläutert. Außerdem wird ein kurzer Einblick gegeben, wie tierbezogene Indikatoren bereits von den Anbauverbänden für die Tierwohl-Kontrolle in der Ökologischen Landwirtschaft eingesetzt werden. Anschließend werden mit den Workshopteilnehmer*innen in kleinen Gruppen drei Themenbereiche betrachtet und diskutiert (Auswahlprozedere der Indikatoren, praktische Anwendung der Indikatoren, Schulungskonzepte). Am Ende der Diskussionsrunden werden die Ergebnisse für alle Teilnehmer*innen zusammengefasst

The Generalized Lyapunov Theorem and its Application to Quantum Channels

We give a simple and physically intuitive necessary and sufficient condition for a map acting on a compact metric space to be mixing (i.e. infinitely many applications of the map transfer any input into a fixed convergency point). This is a generalization of the "Lyapunov direct method". First we prove this theorem in topological spaces and for arbitrary continuous maps. Finally we apply our theorem to maps which are relevant in Open Quantum Systems and Quantum Information, namely Quantum Channels. In this context we also discuss the relations between mixing and ergodicity (i.e. the property that there exist only a single input state which is left invariant by a single application of the map) showing that the two are equivalent when the invariant point of the ergodic map is pure.Comment: 13 pages, 3 figure

Chirality Sensing of Terpenes, Steroids, Amino Acids, Peptides and Drugs with Acyclic Cucurbit[n]urils and Molecular Tweezers

Achiral chromophoric hosts, i.e. acyclic cucurbit[ n ]urils and molecular tweezers, were found to respond with characteristic Circular Dichroism (CD) spectra to the presence of micromolar concentrations of chiral hydrocarbons, terpenes, steroids, amino acids and their derivates, and drugs in water. In favourable cases, this allows for analyte identification or for reaction monitoring