854 research outputs found
Clinical and serologic responses to human âapathogenic' trypanosomes
We describe a female patient suffering from a benign self-healing febrile disease with strongly positive serology for Trypanosoma brucei. The patient showed a clinical picture with similarities to that of human African trypanosomiasis (HAT). HAT due to T. b. gambiense and T. b. rhodesiense were ruled out. We performed serologic tests because the patient was worried about HAT after receiving tsetse bites. The possibilities of an infection with human âapathogenic' trypanosomes such as T. b. brucei, T. congolense or T. vivax are discusse
Comment on "Probabilistic Quantum Memories"
This is a comment on two wrong Phys. Rev. Letters papers by C.A.
Trugenberger. Trugenberger claimed that quantum registers could be used as
exponentially large "associative" memories. We show that his scheme is no
better than one where the quantum register is replaced with a classical one of
equal size.
We also point out that the Holevo bound and more recent bounds on "quantum
random access codes" pretty much rule out powerful memories (for classical
information) based on quantum states.Comment: REVTeX4, 1 page, published versio
Optimizing the colour and fabric of targets for the control of the tsetse fly Glossina fuscipes fuscipes
Background:
Most cases of human African trypanosomiasis (HAT) start with a bite from one of the subspecies of Glossina fuscipes. Tsetse use a range of olfactory and visual stimuli to locate their hosts and this response can be exploited to lure tsetse to insecticide-treated targets thereby reducing transmission. To provide a rational basis for cost-effective designs of target, we undertook studies to identify the optimal target colour.
Methodology/Principal Findings:
On the Chamaunga islands of Lake Victoria , Kenya, studies were made of the numbers of G. fuscipes fuscipes attracted to targets consisting of a panel (25 cm square) of various coloured fabrics flanked by a panel (also 25 cm square) of fine black netting. Both panels were covered with an electrocuting grid to catch tsetse as they contacted the target. The reflectances of the 37 different-coloured cloth panels utilised in the study were measured spectrophotometrically. Catch was positively correlated with percentage reflectance at the blue (460 nm) wavelength and negatively correlated with reflectance at UV (360 nm) and green (520 nm) wavelengths. The best target was subjectively blue, with percentage reflectances of 3%, 29%, and 20% at 360 nm, 460 nm and 520 nm respectively. The worst target was also, subjectively, blue, but with high reflectances at UV (35% reflectance at 360 nm) wavelengths as well as blue (36% reflectance at 460 nm); the best low UV-reflecting blue caught 3Ă more tsetse than the high UV-reflecting blue.
Conclusions/Significance:
Insecticide-treated targets to control G. f. fuscipes should be blue with low reflectance in both the UV and green bands of the spectrum. Targets that are subjectively blue will perform poorly if they also reflect UV strongly. The selection of fabrics for targets should be guided by spectral analysis of the cloth across both the spectrum visible to humans and the UV region
Double Fe-impurity charge state in the topological insulator BiSe
The influence of individual impurities of Fe on the electronic properties of
topological insulator BiSe is studied by Scanning Tunneling Microscopy.
The microscope tip is used in order to remotely charge/discharge Fe impurities.
The charging process is shown to depend on the impurity location in the
crystallographic unit cell, on the presence of other Fe impurities in the close
vicinity, as well as on the overall doping level of the crystal. We present a
qualitative explanation of the observed phenomena in terms of tip-induced local
band bending. Our observations evidence that the specific impurity neighborhood
and the position of the Fermi energy with respect to the Dirac point and bulk
bands have both to be taken into account when considering the electron
scattering on the disorder in topological insulators.Comment: 10 pages, accepted for publication in Applied Physics Letters, minor
bugs were correcte
On compatibility and improvement of different quantum state assignments
When Alice and Bob have different quantum knowledges or state assignments
(density operators) for one and the same specific individual system, then the
problems of compatibility and pooling arise. The so-called first
Brun-Finkelstein-Mermin (BFM) condition for compatibility is reobtained in
terms of possessed or sharp (i. e., probability one) properties. The second BFM
condition is shown to be generally invalid in an infinite-dimensional state
space. An argument leading to a procedure of improvement of one state
assifnment on account of the other and vice versa is presented.Comment: 8 page
Topological mirror symmetry with fluxes
Motivated by SU(3) structure compactifications, we show explicitly how to
construct half--flat topological mirrors to Calabi--Yau manifolds with NS
fluxes. Units of flux are exchanged with torsion factors in the cohomology of
the mirror; this is the topological complement of previous
differential--geometric mirror rules. The construction modifies explicit SYZ
fibrations for compact Calabi--Yaus. The results are of independent interest
for SU(3) compactifications. For example one can exhibit explicitly which
massive forms should be used for Kaluza--Klein reduction, proving previous
conjectures. Formality shows that these forms carry no topological information;
this is also confirmed by infrared limits and old classification theorems.Comment: 35 pages, 5 figure
MOVES â V. Modelling starâplanet magnetic interactions of HD 189733
Funding: AS acknowledges funding from the European Unionâs Horizon-2020 research and innovation programme (grant agreement no. 776403 ExoplANETS-A), the PLATO/CNES grant at CEA/IRFU/DAp, and the Programme National de PlanĂ©tologie (PNP). AS and ASB acknowledge funding from the ERC Synergy grant WholeSun 810218. RF acknowledges funding from UAEU startup grant number G00003269. This work has been carried out in the frame of the National Centre for Competence in Research PlanetS supported by the Swiss National Science Foundation (SNSF). The authors acknowledge the financial support of the SNSF. This project has received funding from the European Research Council (ERC) under the European Unionâs Horizon 2020 research and innovation programme (project Spice Dune, grant agreement no. 947634). ChH acknowledges funding from the European Union H2020-MSCA-ITN-2019 under grant agreement no. 860470 (CHAMELEON). PJW acknowledges support from STFC through consolidated grants ST/L000733/1 and ST/P000495/1. AAV acknowledges funding from the ERC under the European Unionâs Horizon 2020 research and innovation programme (grant agreement no. 817540, ASTROFLOW). PZ acknowledges funding from the ERC under the European Unionâs Horizon 2020 research and innovation programme (grant agreement no. 101020459 - Exoradio).Magnetic interactions between stars and close-in planets may lead to a detectable signal on the stellar disc. HD 189733 is one of the key exosystems thought to harbour magnetic interactions, which may have been detected in 2013 August. We present a set of 12 wind models at that period, covering the possible coronal states and coronal topologies of HD 189733 at that time. We assess the power available for the magnetic interaction and predict its temporal modulation. By comparing the predicted signal with the observed signal, we find that some models could be compatible with an interpretation based on starâplanet magnetic interactions. We also find that the observed signal can be explained only with a stretch-and-break interaction mechanism, while that the AlfvĂ©n wings scenario cannot deliver enough power. We finally demonstrate that the past observational cadence of HD 189733 leads to a detection rate of only between 12 and 23 per cent, which could explain why starâplanet interactions have been hard to detect in past campaigns. We conclude that the firm confirmation of their detection will require dedicated spectroscopic observations covering densely the orbital and rotation period, combined with scarcer spectropolarimetric observations to assess the concomitant large-scale magnetic topology of the star.Publisher PDFPeer reviewe
Nucleon-induced reactions at intermediate energies: New data at 96 MeV and theoretical status
Double-differential cross sections for light charged particle production (up
to A=4) were measured in 96 MeV neutron-induced reactions, at TSL laboratory
cyclotron in Uppsala (Sweden). Measurements for three targets, Fe, Pb, and U,
were performed using two independent devices, SCANDAL and MEDLEY. The data were
recorded with low energy thresholds and for a wide angular range (20-160
degrees). The normalization procedure used to extract the cross sections is
based on the np elastic scattering reaction that we measured and for which we
present experimental results. A good control of the systematic uncertainties
affecting the results is achieved. Calculations using the exciton model are
reported. Two different theoretical approches proposed to improve its
predictive power regarding the complex particle emission are tested. The
capabilities of each approach is illustrated by comparison with the 96 MeV data
that we measured, and with other experimental results available in the
literature.Comment: 21 pages, 28 figure
What parameters affect left ventricular diastolic flow propagation velocity? in vitro studies using color m-mode doppler echocardiography
BACKGROUND: Insufficient data describe the relationship of hemodynamic parameters to left ventricular (LV) diastolic flow propagation velocity (Vp) measured using color M-mode Doppler echocardiography. METHODS: An in vitro LV model used to simulate LV diastolic inflow with Vp measured under conditions of varying: 1) Stroke volume, 2) heart rate (HR), 3) LV volume, 4) LV compliance, and 5) transmitral flow (TMF) waveforms (Type 1: constant low diastasis flow and Type 2: no diastasis flow). RESULTS: Univariate analysis revealed excellent correlations of Vp with stroke volume (r = 0.98), LV compliance (r = 0.94), and HR with Type 1 TMF (r = 0.97). However, with Type 2 TMF, HR was not associated with Vp. LV volume was not related to Vp under low compliance, but inversely related to Vp under high compliance conditions (r = -0.56). CONCLUSION: These in vitro findings may help elucidate the relationship of hemodynamic parameters to early diastolic LV filling
D* Production in Deep Inelastic Scattering at HERA
This paper presents measurements of D^{*\pm} production in deep inelastic
scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The
data have been taken with the ZEUS detector at HERA. The decay channel
(+ c.c.) has been used in the study. The
cross section for inclusive D^{*\pm} production with
and is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region
{ GeV and }. Differential cross
sections as functions of p_T(D^{*\pm}), and are
compared with next-to-leading order QCD calculations based on the photon-gluon
fusion production mechanism. After an extrapolation of the cross section to the
full kinematic region in p_T(D^{*\pm}) and (D^{*\pm}), the charm
contribution to the proton structure function is
determined for Bjorken between 2 10 and 5 10.Comment: 17 pages including 4 figure
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