1,587 research outputs found
Reintroduction of native cotton (Gossypium Barbadian) on the North coast of Peru: analysis of economic feasibility for small producers
In Peru the agro-export boom has determined a major shift of large farmers from traditional agro-industrial crops (coffee and cotton) to new agribusinesses (asparagus, oranges, avocados, apples). These dynamics have left room for the small farmers to enter the traditional agro-industrial sector, or into new niche markets as in the case of native cotton. On the North coast of Peru the cultivation of the native and naturally coloured cotton (Gossypium Barbadense spp. locally called algod\uf3n El Pa\ueds) is part of the Moche indigenous culture (a local pre-Inca population). Since 1949 the Peruvian legal prohibition to produce native cotton, linked to the risk of genetic contamination of the industrial white cotton cultivations, made the keeping of these traditional varieties very difficult. Nevertheless the situation has totally changed since 2008 due to Regulation n\ub0 29224 declaring native cotton as a genetic, ethnic and cultural heritage of the country. This study analyses the economic feasibility of re-inserting the native cotton as part of the agricultural production of 50 farmers on the North coast of Peru, proposing a farm economic data analysis, scenario analysis and sensitivity analysis based on OFAT (One Factor at A Time) methodology: the results attest that in all the productive scenarios proposed (10%, 25% and 50% of the farm agricultural surface growing native cotton) the average farm incomes are going to increase. Moreover the sensitivity analysis attests that also in the worst conditions of a 10% decrease in the native cotton price, the average farm incomes with native cotton are higher compared to the business as usual scenario in all three productive scenarios proposed
Lepton Flavor Violation, Neutralino Dark Matter and the Reach of the LHC
We revisit the phenomenology of the Constrained MSSM with right-handed
neutrinos (CMSSMRN). A supersymmetric seesaw mechanism, generating neutrino
masses and sizable lepton flavour violating (LFV) entries is assumed to be
operative. In this scheme, we study the complementarity between the `observable
ranges' of various paths leading to the possible discovery of low energy SUSY:
the reach of the Cern Large Hadron Collider (LHC), the quest for neutralino
dark matter signals and indirect searches through LFV processes. Within the
regions of the CMSSMRN parameter space compatible with all
cosmo-phenomenological requirements, those which are expected to be probed at
the LHC will be typically also accessible to upcoming LFV experiments.
Moreover, parameter space portions featuring a heavy SUSY particle spectrum
could be well beyond LHC reach while leaving LFV searches as the only key to
get a glimpse on SUSY.Comment: 31 pages, 12 figures, LateX; v2: one reference and one comment added;
matches with published versio
Grand Unification of Quark and Lepton FCNCs
In the context of Supersymmetric Grand Unified theories with soft breaking
terms arising at the Planck scale, it is generally possible to link flavor
changing neutral current and CP violating processes occurring in the leptonic
and hadronic sectors. We study the correlation between flavor changing squark
and slepton mass insertions in models \`a la SU(5). We show that the
constraints coming from lepton flavor violation exhibit a strong impact on
CP-violating B decays.Comment: 4 pages, 1 figur
The Dark Sequential Z' Portal: Collider and Direct Detection Experiments
We revisit the status of a Majorana fermion as a dark matter candidate when a
sequential Z' gauge boson dictates the dark matter phenomenology. Direct dark
matter detection signatures rise from dark matter-nucleus scatterings at bubble
chamber and liquid xenon detectors, and from the flux of neutrinos from the Sun
measured by the IceCube experiment, which is governed by the spin-dependent
dark matter-nucleus scattering. On the collider side, LHC searches for dilepton
and mono-jet + missing energy signals play an important role. The relic density
and perturbativity requirements are also addressed. By exploiting the dark
matter complementarity we outline the region of parameter space where one can
successfully have a Majorana dark matter particle in light of current and
planned experimental sensitivities.Comment: 22 pages, 6 figure
The Rafita asteroid family
The Rafita asteroid family is an S-type group located in the middle main
belt, on the right side of the 3J:-1A mean-motion resonance. The proximity of
this resonance to the family left side in semi-major axis caused many former
family members to be lost. As a consequence, the family shape in the
domain is quite asymmetrical, with a preponderance of objects on the right side
of the distribution. The Rafita family is also characterized by a leptokurtic
distribution in inclination, which allows the use of methods of family age
estimation recently introduced for other leptokurtic families such as Astrid,
Hansa, Gallia, and Barcelona. In this work we propose a new method based on the
behavior of an asymmetry coefficient function of the distribution in the
plane to date incomplete asteroid families such as Rafita. By
monitoring the time behavior of this coefficient for asteroids simulating the
initial conditions at the time of the family formation, we were able to
estimate that the Rafita family should have an age of Myr, in good
agreement with results from independent methods such as Monte Carlo simulations
of Yarkovsky and Yorp dynamical induced evolution and the time behaviour of the
kurtosis of the distribution. Asteroids from the Rafita family can
reach orbits similar to 8\% of the currently known near Earth objects.
1\% of the simulated objects are present in NEO-space during the final
10 Myr of the simulation, and thus would be comparable to objects in the
present-day NEO population.Comment: Accepted 2017 January 19. Received 2017 January 17; in original form
2016 September
Fermion Virtual Effects in Cross Section
We analyse the contribution of new heavy virtual fermions to the cross section. We find that there exists a relevant
interplay between trilinear and bilinear oblique corrections. The result
strongly depends on the chiral or vector--like nature of the new fermions. As
for the chiral case we consider sequential fermions: one obtains substantial
deviation from the Standard model prediction, making the effect possibly
detectable at or GeV linear colliders. As an example for
the vector--like case we take a SUSY extension with heavy charginos and
neutralinos: due to cancellation, the final effect turns out to be negligible.Comment: uuencoded, gz-compressed, tar-ed file. 8 pages, 4 EPS figures, uses
EPSFIG.ST
Hamilton Jacobi Bellman equations in infinite dimensions with quadratic and superquadratic Hamiltonian
We consider Hamilton Jacobi Bellman equations in an inifinite dimensional
Hilbert space, with quadratic (respectively superquadratic) hamiltonian and
with continuous (respectively lipschitz continuous) final conditions. This
allows to study stochastic optimal control problems for suitable controlled
Ornstein Uhlenbeck process with unbounded control processes
Systematic evaluation of software product line architectures
The architecture of a software product line is one of its most important artifacts as it represents an abstraction of the products that can be generated. It is crucial to evaluate the quality attributes of a product line architecture in order to: increase the productivity of the product line process and the quality of the products; provide a means to understand the potential behavior of the products and, consequently, decrease their time to market; and, improve the handling of the product line variability. The evaluation of product line architecture can serve as a basis to analyze the managerial and economical values of a product line for software managers and architects. Most of the current research on the evaluation of product line architecture does not take into account metrics directly obtained from UML models and their variabilities; the metrics used instead are difficult to be applied in general and to be used for quantitative analysis. This paper presents a Systematic Evaluation Method for UML-based Software Product Line Architecture, the SystEM-PLA. SystEM-PLA differs from current research as it provides stakeholders with a means to: (i) estimate and analyze potential products; (ii) use predefined basic UML-based metrics to compose quality attribute metrics; (iii) perform feasibility and trade-off analysis of a product line architecture with respect to its quality attributes; and, (iv) make the evaluation of product line architecture more flexible. An example using the SEI’s Arcade Game Maker (AGM) product line is presented as a proof of concept, illustrating SystEM-PLA activities. Metrics for complexity and extensibility quality attributes are defined and used to
perform a trade-off analysis
INCOMPOSITA: a MADS-box gene controlling prophyll development and floral meristem identity in Antirrhinum
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