393 research outputs found
Life-cycle of the European compost worm Dendrobaena veneta (Oligochaeta)
The life-cycle of Dendrobaena veneta was studied to assess the potential of this species in vermiculture. The development, growth and reproduction were investigated by rearing worms at 25°C on urine-free cattle manure with a moisture content of 80% over a period of 200 days. It was found that cocoons are produced at a mean rate of 0,28 cocoons per worm per day and production can be sustained for at least 200 days. The mean incubation period of the cocoons is 42,1 days with a very low hatching success. The mean number of hatchlings per cocoon that hatched was 1,1. Sexual maturity may be attained within 20 to 35 days but some worms take up to 130 days. Dendrobaena veneta grew well on cattle manure. This species seems to be less suitable than some other epigeic species for vermiculture, at least in terms of its reproductive capacity in the experimental climatic conditions
Motivated reasoning, political sophistication, and associations between President Obama and Islam
Recent polls reveal that between 20% and 25% of Americans erroneously indicate that President Obama is a Muslim. In this article, we compare individuals' explicit responses on a survey about religion and politics with reaction time data from an Implicit Association Test (IAT) to investigate whether individuals truly associate Obama with Islam or are motivated reasoners who simply express negativity about the president when given the opportunity. Our results suggest that predispositions such as ideology, partisanship, and race affect how citizens feel about Obama, which in turn motivates them to accept misinformation about the president. We also find that these implicit associations increase the probability of stating that Obama is likely a Muslim. Interestingly, political sophistication does not appear to inoculate citizens from exposure to misinformation, as they exhibit the same IAT effect as less knowledgeable individuals
Near Extremal Kerr Entropy from AdS_2 Quantum Gravity
We analyze the asymptotic symmetries of near extremal Kerr black holes in
four dimensions using the AdS_2/CFT_1 correspondence. We find a Virasoro
algebra with central charge c_R=12J that is independent from the Virasoro
algebra (with the same central charge) that acts on the degenerate ground
state. The energy of the excitations is computed as well, and we can use
Cardy's formula to determine the near extremal entropy. Our result is
consistent with the Bekenstein-Hawking area law for near extremal Kerr black
holes.Comment: 28 pages. v2: references added, typos correcte
Discovery and Measurement of Sleptons, Binos, and Winos with a Z'
Extensions of the MSSM could significantly alter its phenomenology at the
LHC. We study the case in which the MSSM is extended by an additional U(1)
gauge symmetry, which is spontaneously broken at a few TeV. The production
cross-section of sleptons is enhanced over that of the MSSM by the process
, so the discovery potential for
sleptons is greatly increased. The flavor and charge information in the
resulting decay, , provides a useful handle on
the identity of the LSP. With the help of the additional kinematical constraint
of an on-shell Z', we implement a novel method to measure all of the
superpartner masses involved in this channel. For certain final states with two
invisible particles, one can construct kinematic observables bounded above by
parent particle masses. We demonstrate how output from one such observable,
m_T2, can become input to a second, increasing the number of measurements one
can make with a single decay chain. The method presented here represents a new
class of observables which could have a much wider range of applicability.Comment: 20 pages, 15 figures; v2 references added and minor change
MeV-mass dark matter and primordial nucleosynthesis
The annihilation of new dark matter candidates with masses in the MeV
range may account for the galactic positrons that are required to explain the
511 keV -ray flux from the galactic bulge. We study the impact of
MeV-mass thermal relic particles on the primordial synthesis of H, He,
and Li. If the new particles are in thermal equilibrium with neutrinos
during the nucleosynthesis epoch they increase the helium mass fraction for
m_X\alt 10 MeV and are thus disfavored. If they couple primarily to the
electromagnetic plasma they can have the opposite effect of lowering both
helium and deuterium. For --10 MeV they can even improve the overall
agreement between the predicted and observed H and He abundances.Comment: 11 pages, 10 figures, references and two appendices added,
conclusions unchanged; accepted for publication in Phys.Rev.
From M-ary Query to Bit Query: a new strategy for efficient large-scale RFID identification
The tag collision avoidance has been viewed as one of the most important research problems in RFID communications and bit tracking technology has been widely embedded in query tree (QT) based algorithms to tackle such challenge. Existing solutions show further opportunity to greatly improve the reading performance because collision queries and empty queries are not fully explored. In this paper, a bit query (BQ) strategy based Mary query tree protocol (BQMT) is presented, which can not only eliminate idle queries but also separate collided tags into many small subsets and make full use of the collided bits. To further optimize the reading performance, a modified dual prefixes matching (MDPM) mechanism is presented to allow multiple tags to respond in the same slot and thus significantly reduce the number of queries. Theoretical analysis and simulations are supplemented to validate the effectiveness of the proposed BQMT and MDPM, which outperform the existing QT-based algorithms. Also, the BQMT and MDPM can be combined to BQMDPM to improve the reading performance in system efficiency, total identification time, communication complexity and average energy cost
No Dynamics in the Extremal Kerr Throat
Motivated by the Kerr/CFT conjecture, we explore solutions of vacuum general
relativity whose asymptotic behavior agrees with that of the extremal Kerr
throat, sometimes called the Near-Horizon Extreme Kerr (NHEK) geometry. We
argue that all such solutions are diffeomorphic to the NHEK geometry itself.
The logic proceeds in two steps. We first argue that certain charges must
vanish at all times for any solution with NHEK asymptotics. We then analyze
these charges in detail for linearized solutions. Though one can choose the
relevant charges to vanish at any initial time, these charges are not
conserved. As a result, requiring the charges to vanish at all times is a much
stronger condition. We argue that all solutions satisfying this condition are
diffeomorphic to the NHEK metric.Comment: 42 pages, 3 figures. v3: minor clarifications and correction
Towards a population of HMXB/NS microquasars as counterparts of low-latitude unidentified EGRET sources
The discovery of the microquasar LS 5039 well within the 95% conficence
contour of the Unidentified EGRET Source (UES) 3EG J1824-1514 was a major step
towards the possible association between microquasars (MQs) and UESs. The
recent discovery of precessing relativistic radio jets in LS I +61 303, a
source associated for long time with 2CG 135+01 and with the UES 3EG
J0241+6103, has given further support to this idea. Finally, the very recently
proposed association between the microquasar candidate AX J1639.0-4642 and the
UES 3EG J1639-4702 points towards a population of High Mass X-ray Binary
(HMXB)/Neutron Star (NS) microquasars as counterparts of low-latitude
unidentified EGRET sources.Comment: 12 pages, 7 figures. Proceedings of the Conference "The
Multiwavelength Approach to Unidentified Gamma-ray Sources", to appear in the
journal Astrophysics and Space Scienc
Phase I and pharmacokinetic study of brostallicin (PNU-166196), a new DNA minor-groove binder, administered intravenously every 3 weeks to adult patients with metastatic cancer
PURPOSE: Brostallicin (PNU-166196) is a cytotoxic agent that binds to the
minor groove of DNA with significant antitumor activity in preclinical
studies. This trial was designed to determine the maximum tolerated dose,
the toxicity profile, and the pharmacokinetics of Brostallicin in cancer
patients. Experimental Design: Patients were treated with escalating doses
of Brostallicin ranging from 0.85 to 15 mg/m(2) administered as a 10-min
i.v. infusion every 3 weeks. Blood samples for pharmacokinetic analysis
were collected during the first and second course, and analyzed by
liquid-chromatography with tandem-mass spectrometric detection. RESULTS:
Twenty-seven evaluable patients received a total of 73 courses. Grade 4
neutropenia was the only dose-limiting toxicity at 12.5 mg/m(2), whereas
grade 4 thrombocytopenia (1 patient) and grade 4 neutropenia (2 patients)
were the dose-limiting toxicities at 15 mg/m(2). Other side effects,
including thrombocytopenia and nausea, were generally mild. The maximum
tolerated dose was defined at 10 mg/m(2). The clearance and terminal
half-life of Brostallicin were dose-independent, with mean (+/-SD) values
of 9.33 +/- 2.38 liters/h/m(2) and 4.69 +/- 1.88 h, respectively. There
was no significant accumulation of Brostallicin with repeated
administration. Significant relationships were observed between systemic
exposure to Brostallicin and neutrophil counts at nadir. One partial
response was observed in a patient with a gastrointestinal stromal tumor.
CONCLUSION: Brostallicin was found to be well tolerated, with neutropenia
being the principal toxicity. The recommended dose for additional
evaluation in this schedule is 10 mg/m(2)
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