422 research outputs found
Oriented Birkhoff sections of Anosov flows
This paper gives 3 different proofs (independently obtained by the 3 authors)
of the following fact: given an Anosov flow on an oriented 3 manifold, the
existence of a positive Birkhoff section is equivalent to the fact that the
flow is -covered positively twisted.Comment: 40 pages, 6 figure
„Anti-Intellektualismus“: Auch eine Antwort Theodor W. Adornos auf die Frage: Was ist deutsch?
Theodor W. Adorno gilt als Denker, der ein sehr positives Verhältnis zur deutschen Geisteskultur hatte: Hegel, Marx, Nietzsche – das waren ihm Vorbilder, welche gezeigt hatten, wie sich über die verwaltete Welt nachdenken lässt. Insofern überrascht es nicht, dass Adornos Kritik an der deutschen Universitätskultur selbst in der Adornoforschung für gewöhnlich entweder gar nicht oder nur am Rande besprochen wird. Das ist im Folgenden anders. In drei Schritten (und unter Bezugnahme auf grosse Hauptwerke, auf kleine Nebenarbeiten und auf einen Briefwechsel) wird nachgezeichnet, wie die deutsche Universitätskultur im Adorno’schen Werk einerseits thematisiert, andererseits attackiert wird. Für Adorno ist diese Kultur, so viel sei vorweggenommen, auch durch „Anti-Intellektualismus“ geprägt.
Im ersten Schritt wird aufgezeigt, dass Adorno in vielen Texten – so unter anderem in Minima Moralia – die deutsche Universitätswelt thematisierte. Im zweiten Schritt wird dargelegt, wie Adorno in etlichen Beiträgen – so zum Beispiel in Jargon der Eigentlichkeit – die deutsche Universitätsmilieu attackierte. Schliesslich geht es im dritten Schritt darum, aus einer soziologiegeschichtlichen Perspektive auf die Thematisierung von beziehungsweise auf die Kritik an deutschen Universitätsvertretern zu blicken: Dabei wird thesenhaft illustriert, dass respektive inwiefern der Philosoph, Soziologe und Musiktheoretiker seine harsche Polemik gegenüber der deutschen Universitätskultur im Anschluss an deutsche Universitätsgrössen tätigte, so nicht zuletzt im Anschluss an Max Weber
Special issue: recent advances in Cambrian to modern cephalopod research I
In September 2014, the 9th International Symposium Cephalopods—Present and Past was held at the Universitz of Zurich in combination with the 5th International Coleoid Symposium. Here, give a short account of these two events
Observation of Entangled States of a Fully Controlled 20-Qubit System
We generate and characterise entangled states of a register of 20
individually controlled qubits, where each qubit is encoded into the electronic
state of a trapped atomic ion. Entanglement is generated amongst the qubits
during the out-of-equilibrium dynamics of an Ising-type Hamiltonian, engineered
via laser fields. Since the qubit-qubit interactions decay with distance,
entanglement is generated at early times predominantly between neighbouring
groups of qubits. We characterise entanglement between these groups by
designing and applying witnesses for genuine multipartite entanglement. Our
results show that, during the dynamical evolution, all neighbouring qubit
pairs, triplets, most quadruplets, and some quintuplets simultaneously develop
genuine multipartite entanglement. Witnessing genuine multipartite entanglement
in larger groups of qubits in our system remains an open challenge.Comment: 20 pages, 4 figure
Mosquito repellents for malaria prevention
Background
Malaria is an important cause of illness and death across endemic regions. Considerable success against malaria has been achieved within the past decade mainly through long-lasting insecticide-treated nets (LLINs). However, elimination of the disease is proving difficult as current control methods do not protect against mosquitoes biting outdoors and when people are active. Repellents may provide a personal protection solution during these times.
Objectives
To assess the impact of topical repellents, insecticide-treated clothing, and spatial repellents on malaria transmission.
Search methods
We searched the following databases up to 26 June 2017: the Cochrane Infectious Diseases Group Specialized Register; the Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE; Embase; US AFPMB; CAB Abstracts; and LILACS. We also searched trial registration platforms and conference proceedings; and contacted organizations and companies for ongoing and unpublished trials.
Selection criteria
We included randomized controlled trials (RCTs) and cluster-randomized controlled trials of topical repellents proven to repel mosquitoes; permethrin-treated clothing; and spatial repellents such as mosquito coils. We included trials that investigated the use of repellents with or without LLINs, referred to as insecticide-treated nets.
Data collection and analysis
Two review authors independently reviewed trials for inclusion, extracted the data, and assessed the risk of bias. A third review author resolved any discrepancies. We analysed data by conducting meta-analysis and stratified by whether the trials had included LLINs. We combined results from cRCTs with individually RCTs by adjusting for clustering and presented results using forest plots. We used GRADE to assess the certainty of the evidence.
Main results
Eight cRCTs and two RCTs met the inclusion criteria. Six trials investigated topical repellents, two trials investigated insecticide-treated clothing, and two trials investigated spatial repellents.
Topical repellents
Six RCTS, five of them cluster-randomized, investigated topical repellents involving residents of malaria-endemic regions. Four trials used topical repellents in combination with nets, but two trials undertaken in displaced populations used topical repellents alone. It is unclear if topical repellents can prevent clinical malaria (RR 0.65, 95% CI 0.4 to 1.07, very low certainty evidence) or malaria infection (RR 0.84, 95% CI 0.64 to 1.12, low-certainty evidence) caused by P. falciparum. It is also unclear if there is any protection against clinical cases of P. vivax (RR 1.32, 95% CI 0.99 to 1.76, low-certainty evidence) or incidence of infections (RR 1.07, 95% CI 0.80 to 1.41, low-certainty evidence). Subgroup analysis of trials including insecticide-treated nets did not show a protective effect of topical repellents against malaria. Only two studies did not include insecticide-treated nets, and they measured different outcomes; one reported a protective effect against clinical cases of P. falciparum (RR 0.40, 95% CI 0.23 to 0.71); but the other study measured no protective effect against malaria infection incidence caused by either P. falciparum or P. vivax.
Insecticide-treated clothing
Insecticide-treated clothing were investigated in trials conducted in refugee camps in Pakistan and amongst military based in the Colombian Amazon. Neither study provided participants with insecticide-treated nets. In the absence of nets, treated clothing may reduce the incidence of clinical malaria caused by P. falciparum by approximately 50% (RR 0.49, 95% CI 0.29 to 0.83, low-certainty evidence) and P. vivax (RR 0.64, 95% CI 0.40 to 1.01, low-certainty evidence).
Spatial repellents
Two cluster-randomized RCTs investigated mosquito coils for malaria prevention. We do not know the effect of spatial repellents on malaria prevention (RR 0.24, 95% CI 0.03 to 1.72, very low certainty evidence). There was large heterogeneity between studies and one study had high risk of bias.
Authors' conclusions
There is insufficient evidence to conclude topical or spatial repellents can prevent malaria. There is a need for better designed trials to generate higher certainty of evidence before well-informed recommendations can be made. Adherence to daily compliance remains a major limitation. Insecticide-treated clothing may reduce risk of malaria infection in the absence of insecticide-treated nets; further studies on insecticide-treated clothing in the general population should be done to broaden the applicability of the results
Ghost in the Ising machine
Coupled nonlinear systems have promise for parallel computing architectures.
En route to realizing complex networks for Ising machines, we report an
experimental and theoretical study of two coupled parametric resonators
(parametrons). The coupling severely impacts the bifurcation topology and the
number of available solutions of the system; in part of the stability diagram,
we can access fewer solutions than expected. When applying noise to probe the
stability of the states, we find that the switching rates and the phase-space
trajectories of the system depend on the detuning in surprising ways. We
present a theoretical framework that heralds the existence of 'ghost
bifurcations'. These bifurcations involve only unstable solutions and lead to
avoided zones in phase space. The emergence of such ghost bifurcations is an
important feature of parametron networks that can influence their application
for parallel logic operations
Manipulating and squeezing the photon local density of states with plasmonic nanoparticle networks
International audienceIn this Brief Report, we show that when interconnected networks of gold particles are deposited onto a clean planar surface, they strongly modify the photonic local density of states LDOS in the immediate proximity of the self-assembled nanoparticles. They represent unique architectures for the subwavelength patterning of initially flat photonic LDOS. Moreover, we show that their local spectral signatures are well suited for the generation of sites able to enhance molecular fluorescence intensity
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