8,585 research outputs found
A REVIEW OF THE COMMON AGRICULTURAL POLICY AND THE IMPLICATIONS OF MODIFIED SYSTEMS FOR IRELAND. ESRI BROADSHEET No. 21, October 1983
The first chapter of this paper discusses the reasons for heavy
government involvement in agricultural production and trade
throughout the world and concludes that the answer is basically
related to what farmers produce -- food. Food is a basic primary
want and rightly or wrongly there seems to be an innate feat" that
without market intervention supplies will be erratic and so
sometimes scarce
Logarithmic behavior of degradation dynamics in metal--oxide semiconductor devices
In this paper the authors describe a theoretical simple statistical modelling
of relaxation process in metal-oxide semiconductor devices that governs its
degradation. Basically, starting from an initial state where a given number of
traps are occupied, the dynamics of the relaxation process is measured
calculating the density of occupied traps and its fluctuations (second moment)
as function of time. Our theoretical results show a universal logarithmic law
for the density of occupied traps , i.e., the degradation is logarithmic and its amplitude depends on the
temperature and Fermi Level of device. Our approach reduces the work to the
averages determined by simple binomial sums that are corroborated by our Monte
Carlo simulations and by experimental results from literature, which bear in
mind enlightening elucidations about the physics of degradation of
semiconductor devices of our modern life
Capacities of Grassmann channels
A new class of quantum channels called Grassmann channels is introduced and
their classical and quantum capacity is calculated. The channel class appears
in a study of the two-mode squeezing operator constructed from operators
satisfying the fermionic algebra. We compare Grassmann channels with the
channels induced by the bosonic two-mode squeezing operator. Among other
results, we challenge the relevance of calculating entanglement measures to
assess or compare the ability of bosonic and fermionic states to send quantum
information to uniformly accelerated frames.Comment: 33 pages, Accepted in Journal of Mathematical Physics; The role of
the (fermionic) braided tensor product for quantum Shannon theory, namely
capacity formulas, elucidated; The conclusion on the equivalence of Unruh
effect for bosons and fermions for quantum communication purposes made clear
and even more precis
Phosphorus Fertilizer and Stocking Rate Effects on Soil Microbial Biomass of a Long-Term Dairy Farmlet Experiment
The effects of a range of P fertilizer rates and dairy cow stocking rates on microbial biomass carbon and phosphorus were compared in a long-term farmlet trial in southeastern Australia. Pastures were stocked at 2, 3, or 4 cows/ha and received fertilizer at rates of 0, 35, 70 or 140 kgP/ha. There was no effect of either P fertilizer rate or stocking rate on microbial biomass C from 1995 to 1998. Increasing P application rate significantly increased the chloroform-released microbial P flush measured, but stocking rate had no effect on microbial P. There were significant temporal changes, with the seasonal effects of soil temperature and moisture overriding treatment effects on these microbial measurements
Atomistic modeling of amorphous silicon carbide: An approximate first-principles study in constrained solution space
Localized basis ab initio molecular dynamics simulation within the density
functional framework has been used to generate realistic configurations of
amorphous silicon carbide (a-SiC). Our approach consists of constructing a set
of smart initial configurations that conform essential geometrical and
structural aspects of the materials obtained from experimental data, which is
subsequently driven via first-principles force-field to obtain the best
solution in a reduced solution space. A combination of a priori information
(primarily structural and topological) along with the ab-initio optimization of
the total energy makes it possible to model large system size (1000 atoms)
without compromising the quantum mechanical accuracy of the force-field to
describe the complex bonding chemistry of Si and C. The structural, electronic
and the vibrational properties of the models have been studied and compared to
existing theoretical models and available data from experiments. We demonstrate
that the approach is capable of producing large, realistic configurations of
a-SiC from first-principles simulation that display excellent structural and
electronic properties of a-SiC. Our study reveals the presence of predominant
short-range order in the material originating from heteronuclear Si-C bonds
with coordination defect concentration as small as 5% and the chemical disorder
parameter of about 8%.Comment: 16 pages, 7 figure
The Random Walk in Generalized Quantum Theory
One can view quantum mechanics as a generalization of classical probability
theory that provides for pairwise interference among alternatives. Adopting
this perspective, we ``quantize'' the classical random walk by finding, subject
to a certain condition of ``strong positivity'', the most general Markovian,
translationally invariant ``decoherence functional'' with nearest neighbor
transitions.Comment: 25 pages, no figure
Social media engagement and organic post effectiveness: A roadmap for increasing the effectiveness of social media use in hospitality industry
The present study assessed the social media use behavior of luxury hospitality facilities and offers suggestions to improve organic post effectiveness. All five-star tourism facilities operating in Turkey were incorporated into the study and publicly available post data on Facebook accounts of 441 facilities (out of a total of 612) were examined in the high tourist season (August) for one month. Data on 2,012 Facebook posts were obtained manually and filtered down to 1,847. The collected post data were subsequently coded using a content analysis form and analyzed via ordinal regression. The results highlighted the positive effects of interactive content and vivid content as well as the significance of the content type in achieving higher interaction among followers. The facility location and category (hotel, holiday village, thermal hotel) also emerged as significant factors affecting follower interactions
The EULARâOMERACT rheumatoid arthritis MRI reference image atlas: the metacarpophalangeal joints
This paper presents the metacarpophalangeal (MCP) joint magnetic resonance images of the EULARâOMERACT rheumatoid arthritis MRI reference image atlas. The illustrations include synovitis in the MCP joints (OMERACT RA magnetic resonance imaging scoring system (RAMRIS), grades 0â3), bone oedema in the metacarpal head and the phalangeal base (grades 0â3), and bone erosion in the metacarpal head and the phalangeal base (grades 0â3, and examples of higher grades). The presented reference images can be used to guide scoring of MCP joints according to the OMERACT RA MRI scoring system
Pairing Neutral Cues with Alcohol Intoxication: New Findings in Executive and Attention Networks
Rationale:
Alcohol-associated stimuli capture attention, yet drinkers differ in the precise stimuli that become paired with intoxication.
Objectives:
Extending our prior work to examine the influence of alcoholism risk factors, we paired abstract visual stimuli with intravenous alcohol delivered covertly and examined brain responses to these Pavlovian conditioned stimuli in fMRI when subjects were not intoxicated.
Methods:
Sixty healthy drinkers performed task-irrelevant alcohol conditioning that presented geometric shapes as conditioned stimuli. Shapes were paired with a rapidly rising alcohol limb (CS+) using intravenous alcohol infusion targeting a final peak breath alcohol concentration of 0.045 g/dL or saline (CSâ) infusion at matched rates. On day two, subjects performed monetary delay discounting outside the scanner to assess delay tolerance and then underwent event-related fMRI while performing the same task with CS+, CSâ, and an irrelevant symbol.
Results:
CS+ elicited stronger activation than CSâ in frontoparietal executive/attention and orbitofrontal reward-associated networks. Risk factors including family history, recent drinking, sex, and age of drinking onset did not relate to the [CS+ > CSâ] activation. Delay-tolerant choice and [CS+ > CSâ] activation in right inferior parietal cortex were positively related.
Conclusions:
Networks governing executive attention and reward showed enhanced responses to stimuli experimentally paired with intoxication, with the right parietal cortex implicated in both alcohol cue pairing and intertemporal choice. While different from our previous study results in 14 men, we believe this paradigm in a large sample of male and female drinkers offers novel insights into Pavlovian processes less affected by idiosyncratic drug associations
Recognition without identification, erroneous familiarity, and déjà vu
Déjà vu is characterized by the recognition of a situation concurrent with the awareness that this recognition is inappropriate. Although forms of déjà vu resolve in favor of the inappropriate recognition and therefore have behavioral consequences, typical déjà vu experiences resolve in favor of the awareness that the sensation of recognition is inappropriate. The resultant lack of behavioral modification associated with typical déjà vu means that clinicians and experimenters rely heavily on self-report when observing the experience. In this review, we focus on recent déjà vu research. We consider issues facing neuropsychological, neuroscientific, and cognitive experimental frameworks attempting to explore and experimentally generate the experience. In doing this, we suggest the need for more experimentation and amore cautious interpretation of research findings, particularly as many techniques being used to explore déjà vu are in the early stages of development.PostprintPeer reviewe
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