24,947 research outputs found
Theoretical Guidance on the Determinants of Success in Agricultural Marketing and Production Clubs
Institutional and Behavioral Economics, Marketing,
Nine percent nickel steel heavy forging weld repair study
The feasibility of making weld repairs on heavy section 9% nickel steel forgings such as those being manufactured for the National Transonic Facility fan disk and fan drive shaft components was evaluated. Results indicate that 9% nickel steel in heavy forgings has very good weldability characteristics for the particular weld rod and weld procedures used. A comparison of data for known similar work is included
Forming Disk Galaxies in Lambda CDM Simulations
We used fully cosmological, high resolution N-body + SPH simulations to
follow the formation of disk galaxies with rotational velocities between 135
and 270 km/sec in a Lambda CDM universe. The simulations include gas cooling,
star formation, the effects of a uniform UV background and a physically
motivated description of feedback from supernovae. The host dark matter halos
have a spin and last major merger redshift typical of galaxy sized halos as
measured in recent large scale N--Body simulations. The simulated galaxies form
rotationally supported disks with realistic exponential scale lengths and fall
on both the I-band and baryonic Tully Fisher relations. An extended stellar
disk forms inside the Milky Way sized halo immediately after the last major
merger. The combination of UV background and SN feedback drastically reduces
the number of visible satellites orbiting inside a Milky Way sized halo,
bringing it in fair agreement with observations. Our simulations predict that
the average age of a primary galaxy's stellar population decreases with mass,
because feedback delays star formation in less massive galaxies. Galaxies have
stellar masses and current star formation rates as a function of total mass
that are in good agreement with observational data. We discuss how both high
mass and force resolution and a realistic description of star formation and
feedback are important ingredients to match the observed properties of
galaxies.Comment: Revised version after the referee's comments. Conclusions unchanged.
2 new plots. MNRAS in press. 20 plots. 21 page
Quantum interference and sub-Poissonian statistics for time-modulated driven dissipative nonlinear oscillator
We show that quantum-interference phenomena can be realized for the
dissipative nonlinear systems exhibiting hysteresis-cycle behavior and quantum
chaos. Such results are obtained for a driven dissipative nonlinear oscillator
with time-dependent parameters and take place for the regimes of long time
intervals exceeding dissipation time and for macroscopic levels of oscillatory
excitation numbers. Two schemas of time modulation: (i) periodic variation of
the strength of the {\chi}(3) nonlinearity; (ii) periodic modulation of the
amplitude of the driving force, are considered. These effects are obtained
within the framework of phase-space quantum distributions. It is demonstrated
that the Wigner functions of oscillatory mode in both bistable and chaotic
regimes acquire negative values and interference patterns in parts of
phase-space due to appropriately time-modulation of the oscillatory nonlinear
dynamics. It is also shown that the time-modulation of the oscillatory
parameters essentially improves the degree of sub-Poissonian statistics of
excitation numbers
Magnetoresistance and magnetic breakdown in the quasi-two-dimensional conductors (BEDT-TTF)MHg(SCN)[M=K,Rb,Tl]
The magnetic field dependence of the resistance of
(BEDT-TTF)MHg(SCN)[M=K,Rb,Tl] in the density-wave phase is explained in
terms of a simple model involving magnetic breakdown and a reconstructed Fermi
surface. The theory is compared to measurements in pulsed magnetic fields up to
51 T. The value implied for the scattering time is consistent with independent
determinations. The energy gap associated with the density-wave phase is
deduced from the magnetic breakdown field. Our results have important
implications for the phase diagram.Comment: 5 pages, RevTeX + epsf, 3 figures. To appear in Physical Review B,
Rapid Communications, September 15, 199
Non-symmetric liquid crystal dimer containing a carbohydrate-based moiety
Peer reviewedPublisher PD
The Prognostic Effect of Ethnicity for Gastric and Esophageal Cancer: The Population-Based Experience in British Columbia, Canada
Background: Gastric and esophageal cancers are among the most lethal human malignancies. Their epidemiologyis geographically diverse. This study compares the survival of gastric and esophageal cancer patients amongseveral ethnic groups including Chinese, South Asians, Iranians and Others in British Columbia (BC), Canada.Methods: Data were obtained from the population-based BC Cancer Registry for patients diagnosed with invasiveesophageal and gastric cancer between 1984 and 2006. The ethnicity of patients was estimated according to theirnames and categorized as Chinese, South Asian, Iranian or Other. Cox proportional hazards regression analysis wasused to estimate the effect of ethnicity adjusted for patient sex and age, disease histology, tumor location, diseasestage and treatment.Results: The survival of gastric cancer patients was significantly different among ethnic groups. Chinese patientsshowed better survival compared to others in univariate and multivariate analysis. The survival of esophagealcancer patients was significantly different among ethnic groups when the data was analyzed by a univariate test(p = 0.029), but not in the Cox multivariate model adjusted for other patient and prognostic factors.Conclusions: Ethnicity may represent underlying genetic factors. Such factors could influence host-tumorinteractions by altering the tumor’s etiology and therefore its chance of spreading. Alternatively, genetic factorsmay determine response to treatments. Finally, ethnicity may represent non-genetic factors that affect survival.Differences in survival by ethnicity support the importance of ethnicity as a prognostic factor, and may provideclues for the future identification of genetic or lifestyle factors that underlie these observations
Production, income, and expenditure in commercial sexual activity as a measure of GDP in the UK national accounts
Executive summary: This paper reports the economic activity of sex workers for its inclusion into gross domestic product (GDP) for the UK National Accounts. Markets in consenting but nonetheless illicit activities, including commercial sexual activity and drugs, were incorporated into figures for the UK National Accounts for the first time in 2014. This was to ensure comparability of the Gross National Income (GNI) measurements across EU countries. We evaluate the methods and data used to calculate prostitution in the first ONS (2014) analysis and explore the constraints and limitations in the calculation of prostitution data.
We provide an updated figure for the number of sex workers using monitoring data from NHS specialist services and a using a standard methodology that has been employed by HIV prevention organisations across Europe to supply estimates of the number of sex workers in the UK as well as income and expenditure in various sex work markets in which both parties are voluntary participants. The London and regional markets are sectored separately to take account of the denser market in the capital, and to reflect the composition and differential pricing and working practices of sex workers in different sectors based on location and gender.
Trying to estimate informal covert markets and activities presents an immense methodological challenge. Not surprisingly there have been few attempts to estimate this hidden part of the UK economy in the peer-reviewed literature or from quality sources. To date only Kinnell (1999), and Cusick, Kinnell, Brooks-Gordon and Campbell (2009) have attempted it in the UK. There remain significant limitations and levels of uncertainty, but we provide a model that is based on primary and secondary data from national and regional governmental and NGO services, to develop a model of the non-observed economy (NOE) which is scalable, simple, and with more explanatory power than previous attempts, to create a framework for the future calculation of this activity in the UK National Accounts
KIC 10449976: discovery of an extreme-helium subdwarf in the Kepler field
Optical spectroscopy of the blue star KIC 10449976 shows that it is an
extremely helium-rich subdwarf with effective temperature T=40000+/-300 K and
surface gravity log g=5.3+/-0.1. Radial-velocity measurements over a five-day
timescale show an upper variability limit of ~50+/-20 km/s. Kepler photometry
of KIC 10449976 in both long and short cadence modes shows evidence for a
periodic modulation on a timescale of ~3.9 days. We have examined the
possibility that this modulation is not astrophysical but conclude it is most
likely real. We discuss whether the modulation could be caused by a low-mass
companion, by stellar pulsations, or by spots. The identification of any one of
these as cause has important consequences for understanding the origin of
helium-rich subdwarfs.Comment: Accepted by MNRA
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