160 research outputs found
Induced plant-defenses suppress herbivore reproduction but also constrain predation of their offspring
Inducible anti-herbivore defenses in plants are predominantly regulated by jasmonic acid (JA). On tomato plants, most genotypes of the herbivorous generalist spider mite Tetranychus urticae induce JA defenses and perform poorly on it, whereas the Solanaceae specialist Tetranychus evansi, who suppresses JA defenses, performs well on it. We asked to which extent these spider mites and the predatory mite Phytoseiulus longipes preying on these spider mites eggs are affected by induced JA-defenses. By artificially inducing the JA-response of the tomato JA-biosynthesis mutant def-1 using exogenous JA and isoleucine (Ile), we first established the relationship between endogenous JA-Ile-levels and the reproductive performance of spider mites. For both mite species we observed that they produced more eggs when levels of JA-Ile were low. Subsequently, we allowed predatory mites to prey on spider mite-eggs derived from wild-type tomato plants, def-1 and JA-Ile-treated def-1 and observed that they preferred, and consumed more, eggs produced on tomato plants with weak JA defenses. However, predatory mite oviposition was similar across treatments. Our results show that induced JA-responses negatively affect spider mite performance, but positively affect the survival of their offspring by constraining egg-predation
Induced plant-defenses suppress herbivore reproduction but also constrain predation of their offspring
Reconsidering accident causation analysis and evaluating the safety benefits of technologies: final results of the TRACE project
The objectives of the EU-funded project TRACE
(TRaffic Accident Causation in Europe, 2006-2008)
are the up-dating of the etiology of road accidents
and the assessment of the safety benefits of
promising technology-based solutions.
The analyses are based on available, reliable and
accessible existing databases (access to which has
been greatly facilitated by a number of partners
highly experienced in safety analysis, coming from 8
different countries and having access to different
kinds of databases, in-depth or regional or national
statistics in their own country).
Apart from considerable improvements in the
methodologies applicable to accident research in the
field of human factors, statistics and epidemiology, allowing a better understanding of the crash
generating issues, the TRACE project quantified the
expected safety benefits for existing and future safety
applications.
As for existing safety functions or safety packages,
the main striking results show that any increment of a
passive or active safety function selected in this
project produces additional safety benefits. In general,
the safety gains are even higher for higher injury
severity levels. For example, if all cars were Euro
NCAP five stars and fitted with EBA and ESC,
compared to four stars without ESC and EBA, injury
accidents would be reduced by 47%, all injuries
would be mitigated by 68% and severe + fatal
injuries by 70%. As for future advanced safety functions, TRACE
investigated 19 safety systems. The results show that
the greatest additional safety gains potential are
expected from intelligent speed adaptation systems,
automatic crash notification systems, and collision
warning and collision avoidance systems. Their
expected benefits (expected reduction in the total
number of injured persons if the fleet is 100%
equipped) are between 6% and 11%. Safety benefits
of other systems are more often below 5%. Some
systems have a very low expected safety benefit
(around or less than 1%)
Lifetime Differences, direct CP Violation and Partial Widths in D0 Meson Decays to K+K- and pi+pi-
We describe several measurements using the decays D0->K+K- and pi+pi-. We
find the ratio of partial widths, Gamma(D0->K+K-)/Gamma(D0->pi+pi-), to be
2.96+/-0.16+/-0.15, where the first error is statistical and the second is
systematic. We observe no evidence for direct CP violation, obtaining A_CP(KK)
= (0.0+/-2.2+/-0.8)% and A_CP(pipi = (1.9+/-3.2+/-0.8)%. In the limit of no CP
violation we measure the mixing parameter y_CP = -0.012+/-0.025+/-0.014 by
measuring the lifetime difference between D0->K+ K- or pi+pi- and the CP
neutral state, D0->K-pi+. We see no evidence for mixing.Comment: 14 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PRD, Rapid Communicatio
Brucellosis in Sub-Saharan Africa:Current challenges for management, diagnosis and control
Brucellosis is a highly contagious zoonosis caused by bacteria of the genus Brucella and affecting domestic and wild mammals. In this paper, the bacteriological and serological evidence of brucellosis in Sub-Saharan Africa (SSA) and its epidemiological characteristics are discussed. The tools available for the diagnosis and treatment of human brucellosis and for the diagnosis and control of animal brucellosis and their applicability in the context of SSA are presented and gaps identified. These gaps concern mostly the need for simpler and more affordable antimicrobial treatments against human brucellosis, the development of a B. melitensis vaccine that could circumvent the drawbacks of the currently available Rev 1 vaccine, and the investigation of serological diagnostic tests for camel brucellosis and wildlife. Strategies for the implementation of animal vaccination are also discussed.Publishe
Cabibbo-Suppressed Decays of D^+ \to \pi^+\pi^0, K^+\bar{K}^0, K^+\pi^0
Using a 13.7 fb-1 data sample collected with the CLEO II and II.V detectors,
we report new branching fraction measurements for two Cabibbo-suppressed decay
modes of the D+ meson: BR(D+ -> pi+ pi0) = (1.31 +/- 0.17 +/- 0.09 +/- 0.09) x
10^(-3)and BR(D+ -> K+ K0bar) = (5.24 +/- 0.43 +/- 0.20 +/- 0.34) x 10^(-3)
which are significant improvements over past measurements. The errors reflect
statistical and systematical uncertainties as well as the uncertainty in the
absolute D+ branching fraction scale. We also set the first 90% confidence
level upper limit on the branching fraction of the doubly Cabibbo-suppressed
decay mode BR(D+ -> K+ pi0) < 4.2 x 10^(-4).Comment: 8 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Study of ttbar Production in ppbar Collisions Using Total Transverse Energy
We analyze a sample of W + jet events collected with the Collider Detector at
Fermilab (CDF) in ppbar collisions at sqrt(s) = 1.8 TeV to study ttbar
production. We employ a simple kinematical variable "H", defined as the scalar
sum of the transverse energies of the lepton, neutrino and jets. For events
with a W boson and four or more jets, the shape of the "H" distribution
deviates by 3.8 standard deviations from that expected from known backgrounds
to ttbar production. However this distribution agrees well with a linear
combination of background and ttbar events, the agreement being best for a top
mass of 180 GeV/c^2.Comment: Postscript file (gzip+uuencode). 5-page, two-column PRL format
(RevTex). Submitted to Phys. Rev. Lett. 09 June 199
Riociguat treatment in patients with chronic thromboembolic pulmonary hypertension: Final safety data from the EXPERT registry
Objective: The soluble guanylate cyclase stimulator riociguat is approved for the treatment of adult patients with pulmonary arterial hypertension (PAH) and inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH) following Phase
Search for gravitational-wave transients associated with magnetar bursts in advanced LIGO and advanced Virgo data from the third observing run
Gravitational waves are expected to be produced from neutron star oscillations associated with magnetar giant f lares and short bursts. We present the results of a search for short-duration (milliseconds to seconds) and longduration (∼100 s) transient gravitational waves from 13 magnetar short bursts observed during Advanced LIGO, Advanced Virgo, and KAGRA’s third observation run. These 13 bursts come from two magnetars, SGR1935 +2154 and SwiftJ1818.0−1607. We also include three other electromagnetic burst events detected by FermiGBM which were identified as likely coming from one or more magnetars, but they have no association with a known magnetar. No magnetar giant flares were detected during the analysis period. We find no evidence of gravitational waves associated with any of these 16 bursts. We place upper limits on the rms of the integrated incident gravitational-wave strain that reach 3.6 × 10−²³ Hz at 100 Hz for the short-duration search and 1.1 ×10−²² Hz at 450 Hz for the long-duration search. For a ringdown signal at 1590 Hz targeted by the short-duration search the limit is set to 2.3 × 10−²² Hz. Using the estimated distance to each magnetar, we derive upper limits upper limits on the emitted gravitational-wave energy of 1.5 × 1044 erg (1.0 × 1044 erg) for SGR 1935+2154 and 9.4 × 10^43 erg (1.3 × 1044 erg) for Swift J1818.0−1607, for the short-duration (long-duration) search. Assuming isotropic emission of electromagnetic radiation of the burst fluences, we constrain the ratio of gravitational-wave energy to electromagnetic energy for bursts from SGR 1935+2154 with the available fluence information. The lowest of these ratios is 4.5 × 103
Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO
The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages
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