338 research outputs found
Fluctuations of company yearly profits versus scaled revenue: Fat tail distribution of Levy type
We analyze annual revenues and earnings data for the 500 largest-revenue U.S.
companies during the period 1954-2007. We find that mean year profits are
proportional to mean year revenues, exception made for few anomalous years,
from which we postulate a linear relation between company expected mean profit
and revenue. Mean annual revenues are used to scale both company profits and
revenues. Annual profit fluctuations are obtained as difference between actual
annual profit and its expected mean value, scaled by a power of the revenue to
get a stationary behavior as a function of revenue. We find that profit
fluctuations are broadly distributed having approximate power-law tails with a
Levy-type exponent , from which we derive the associated
break-even probability distribution. The predictions are compared with
empirical data.Comment: 6 pages, 6 figure
Ordering variable for parton showers
The parton splittings in a parton shower are ordered according to an ordering
variable, for example the transverse momentum of the daughter partons relative
to the direction of the mother, the virtuality of the splitting, or the angle
between the daughter partons. We analyze the choice of the ordering variable
and conclude that one particular choice has the advantage of factoring softer
splittings from harder splittings graph by graph in a physical gauge.Comment: 28 pages, 5 figure
Solving integral equations in
A dispersive analysis of decays has been performed in the past
by many authors. The numerical analysis of the pertinent integral equations is
hampered by two technical difficulties: i) The angular averages of the
amplitudes need to be performed along a complicated path in the complex plane.
ii) The averaged amplitudes develop singularities along the path of integration
in the dispersive representation of the full amplitudes. It is a delicate
affair to handle these singularities properly, and independent checks of the
obtained solutions are demanding and time consuming. In the present article, we
propose a solution method that avoids these difficulties. It is based on a
simple deformation of the path of integration in the dispersive representation
(not in the angular average). Numerical solutions are then obtained rather
straightforwardly. We expect that the method also works for .Comment: 11 pages, 10 Figures. Version accepted for publication in EPJC. The
ancillary files contain an updated set of fundamental solutions. The
numerical differences to the former set are tiny, see the READMEv2 file for
detail
Accelerated Antigen Instability Testing Reveals Quantitative Mass Spectrometry Analysis Overcomes Specimen Limitations Associated with Diagnostic PD-L1 Testing
Dark Matter from Minimal Flavor Violation
We consider theories of flavored dark matter, in which the dark matter
particle is part of a multiplet transforming nontrivially under the flavor
group of the Standard Model in a manner consistent with the principle of
Minimal Flavor Violation (MFV). MFV automatically leads to the stability of the
lightest state for a large number of flavor multiplets. If neutral, this
particle is an excellent dark matter candidate. Furthermore, MFV implies
specific patterns of mass splittings among the flavors of dark matter and
governs the structure of the couplings between dark matter and ordinary
particles, leading to a rich and predictive cosmology and phenomenology. We
present an illustrative phenomenological study of an effective theory of a
flavor SU(3)_Q triplet, gauge singlet scalar.Comment: 10 pages, 2 figures; v2: references added, minor changes to collider
analysis, conclusions unchange
UV activation of polymeric high aspect ratio microstructures: Ramifications in antibody surface loading for circulating tumor cell selection
The need to activate thermoplastic surfaces using robust and efficient methods has been driven by the fact that replication techniques can be used to produce microfluidic devices in a high production mode and at low cost, making polymer microfluidics invaluable for in vitro diagnostics, such as circulating tumor cell (CTC) analysis, where device disposability is critical to mitigate artifacts associated with sample carryover. Modifying the surface chemistry of thermoplastic devices through activation techniques can be used to increase the wettability of the surface or to produce functional scaffolds to allow for the covalent attachment of biologics, such as antibodies for CTC recognition. Extensive surface characterization tools were used to investigate UV activation of various surfaces to produce uniform and high surface coverage of functional groups, such as carboxylic acids in microchannels of different aspect ratios. We found that the efficiency of the UV activation process is highly dependent on the microchannel aspect ratio and the identity of the thermoplastic substrate. Colorimetric assays and fluorescence imaging of UV-activated microchannels following EDC/NHS coupling of Cy3-labeled oligonucleotides indicated that UV-activation of a PMMA microchannel with an aspect ratio of ???3 was significantly less efficient toward the bottom of the channel compared to the upper sections. This effect was a consequence of the bulk polymer's damping of the modifying UV radiation due to absorption artifacts. In contrast, this effect was less pronounced for COC. Moreover, we observed that after thermal fusion bonding of the device's cover plate to the substrate, many of the generated functional groups buried into the bulk rendering them inaccessible. The propensity of this surface reorganization was found to be higher for PMMA compared to COC. As an example of the effects of material and microchannel aspect ratios on device functionality, thermoplastic devices for the selection of CTCs from whole blood were evaluated, which required the immobilization of monoclonal antibodies to channel walls. From our results, we concluded the CTC yield and purity of isolated CTCs were dependent on the substrate material with COC producing the highest clinical yields for CTCs as well as better purities compared to PMMA.close9
Recent Advances in Graph Partitioning
We survey recent trends in practical algorithms for balanced graph
partitioning together with applications and future research directions
Low-risk persistent gestational trophoblastic disease treated with low-dose methotrexate: efficacy, acute and long-term effects
The aim of this study was to evaluate the efficacy and toxicity of low-dose methotrexate with folinic acid rescue in a large series of consecutively treated patients with low-risk persistent gestational trophoblastic disease. Between January 1987 and December 2000, 250 patients were treated with intramuscular methotrexate (50âmg on alternate days 1, 3, 5, 7) with folinic acid (7.5âmg orally on alternate days 2, 4, 6, 8) rescue. The overall complete response rate without recurrence was 72% for first-line treatment and 95% for those who required second-line chemotherapy. Eight women (3.2%) had recurrence following remission and two (0.8%) had new moles. Two women (0.8%) died of their disease giving an overall cure of 99%. Only 10 women (4%) experienced grade III/IV toxicity during the first course of treatment and 13 women (5.2%) subsequently. Toxicity included mucositis and stomatitis, pleuritic chest pain, thrombocytopenia, uterine bleeding, abdominal pain, liver function changes, rash and pericardial effusion. A total of 59 women (23.6%) required second-line chemotherapy; 48 women had methotrexate resistance, eight had methotrexate toxicity and an empirical decision to change therapy was made in three. In all, 11 women (4.4%) had a hysterectomy before, during or after treatment; 141 women (56.4%) became pregnant following treatment: in 128 (90.7%), the outcome was successful. Methotrexate with folinic acid rescue is an effective treatment for low-risk persistent trophoblastic disease. It has minimal severe toxicity, excellent cure rates and does not appear to affect fertility
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