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Finance Without Brownian Motions: An Introduction To Simplified Stochastic Calculus
The paper introduces a simple way of recording and manipulating stochastic processes without explicit reference to a probability measure. In the new calculus, operations traditionally presented in a measure-specific way are instead captured by tracing the behaviour of jumps (also when no jumps are physically present). The new calculus is thus intuitive and compact. The calculus is also fail-safe in that, under minimal assumptions, all formal calculations are guaranteed to yield mathematically well-defined stochastic processes. Several illustrative examples of the new concept are given, among them a novel result on the Margrabe option to exchange one defaultable asset for another
Les difficultés de la replantation : quel avenir pour le cacao en Côte d'Ivoire ?
Despite their name, "perennial crops" are not really perennial. Tree crop systems are rarely sustainable. Massive migrations, which usually accompany commodity booms, make them especially fragile. Replanting is also more difficult, and more costly, than planting. This is an investment issue, which is neither purely technical nor specific to tree crops. Any social and economic entity, one day a another, faces a major problem in renewing its capitol and ideas. Nevertheless, the loss of the fares rent, and the complexity of rural societies built through massive migrations, certainly lead to aggravated risks of non-sustainability and political errors, The local determinants of the replanting decision, and the environment that enables farmers to try to overcome replanting difficulties, are evaluated here through two village case studies in Côte d'Ivoire. Farmers' initiatives show promise, but are insufficient, There is a need for a strong replanting policy. Instead, as happened in the post in other household rural economies, the country is running a high risk of serious conflicts over land. (Résumé d'auteur
Freeze-Dried Human Leukocytes Stabilized with Uranyl Acetate During Low Temperature Embedding or with OsO4 Vapor After Embedding
Two new simple stabilization procedures for freeze-dried biological material are introduced which are compatible with low temperature embedding (LTE) in Lowicryl. The first method uses a Lowicryl K11M/HM20 mixture supplemented with 0.3% uranyl acetate for LTE. For the second method polymerized Lowicryl blocks containing the freeze-dried material are exposed to OsO4 vapor which penetrates into the Lowicryl block and stabilizes the embedded specimen. The quality of structural preservation is demonstrated with human leukocytes
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Pure-jump semimartingales
A taxonomic hierarchy of pure-jump semimartingales is introduced. This hierarchy contains, in particular, the class of sigma-locally finite variation pure-jump processes. The members of this family can be explicitly characterized in terms of the predictable compensators of their jump measures. This family is also closed under stochastic integration and smooth transformations
Quantifying electronic correlation strength in a complex oxide: a combined DMFT and ARPES study of LaNiO
The electronic correlation strength is a basic quantity that characterizes
the physical properties of materials such as transition metal oxides.
Determining correlation strengths requires both precise definitions and a
careful comparison between experiment and theory. In this paper we define the
correlation strength via the magnitude of the electron self-energy near the
Fermi level. For the case of LaNiO, we obtain both the experimental and
theoretical mass enhancements by considering high resolution
angle-resolved photoemission spectroscopy (ARPES) measurements and density
functional + dynamical mean field theory (DFT + DMFT) calculations. We use
valence-band photoemission data to constrain the free parameters in the theory,
and demonstrate a quantitative agreement between the experiment and theory when
both the realistic crystal structure and strong electronic correlations are
taken into account. These results provide a benchmark for the accuracy of the
DFT+DMFT theoretical approach, and can serve as a test case when considering
other complex materials. By establishing the level of accuracy of the theory,
this work also will enable better quantitative predictions when engineering new
emergent properties in nickelate heterostructures.Comment: 10 pages, 5 figure
Pengembagan Lembar Kerja Siswa Berbasis Kontekstual untuk Membentuk Literasi Sains pada Pembelajaran Fisika Materi Listrik Dinamis Kelas IX SMP
The aim of this research is to produce student worksheet based on contextual to form science literacy that valid. Benefits of this research is the product can be used as teaching material teacher guide, increaseknowledge of science , guiding students in self-development as well as providing literacy skills of science and students\u27 critical thinking skills. The research method used is Research and Development (R & D). Method steps include potentials and problems, literature and information review, product design, validation, and proven design. The result of the research shows the validity of LKS stucture is 100% with High category. In the validity of the contents of the LKS done twice with the results of the first validation of 76, 83% with high category but not valid because there are still indicators Low category. After making the improvement, the second validation result is 80.08% with High category. The Student Worksheet is declared valid and suitable for use by the school as a teaching material and is recommended to continue the research in the form of application as a trial to the school with the manufacture of mass products
Critical sets of nonlinear Sturm-Liouville operators of Ambrosetti-Prodi type
The critical set C of the operator F:H^2_D([0,pi]) -> L^2([0,pi]) defined by
F(u)=-u''+f(u) is studied. Here X:=H^2_D([0,pi]) stands for the set of
functions that satisfy the Dirichlet boundary conditions and whose derivatives
are in L^2([0,pi]). For generic nonlinearities f, C=\cup C_k decomposes into
manifolds of codimension 1 in X. If f''0, the set C_j is shown to be
non-empty if, and only if, -j^2 (the j-th eigenvalue of u -> u'') is in the
range of f'. The critical components C_k are (topological) hyperplanes.Comment: 6 pages, no figure
Spatio-Temporal Differences in Dystrophin Dynamics at mRNA and Protein Levels Revealed by a Novel FlipTrap Line
Dystrophin (Dmd) is a structural protein that links the extracellular matrix to actin filaments in muscle fibers and is required for the maintenance of muscles integrity. Mutations in Dmd lead to muscular dystrophies in humans and other vertebrates. Here, we report the characterization of a zebrafish gene trap line that fluorescently labels the endogenous Dmd protein (Dmd-citrine, Gt(dmd-citrine) ^(ct90a)). We show that the Dmd-citrine line recapitulates endogenous dmd transcript expression and Dmd protein localization. Using this Dmd-citrine line, we follow Dmd localization to the myosepta in real-time using time-lapse microscopy, and find that the accumulation of Dmd protein at the transverse myosepta coincides with the onset of myotome formation, a critical stage in muscle maturation. We observed that Dmd protein localizes specifically to the myosepta prior to dmd mRNA localization. Additionally, we demonstrate that the Dmd-citrine line can be used to assess muscular dystrophy following both genetic and physical disruptions of the muscle
Proposal to Search for Heavy Neutral Leptons at the SPS
A new fixed-target experiment at the CERN SPS accelerator is proposed that
will use decays of charm mesons to search for Heavy Neutral Leptons (HNLs),
which are right-handed partners of the Standard Model neutrinos. The existence
of such particles is strongly motivated by theory, as they can simultaneously
explain the baryon asymmetry of the Universe, account for the pattern of
neutrino masses and oscillations and provide a Dark Matter candidate.
Cosmological constraints on the properties of HNLs now indicate that the
majority of the interesting parameter space for such particles was beyond the
reach of the previous searches at the PS191, BEBC, CHARM, CCFR and NuTeV
experiments. For HNLs with mass below 2 GeV, the proposed experiment will
improve on the sensitivity of previous searches by four orders of magnitude and
will cover a major fraction of the parameter space favoured by theoretical
models.
The experiment requires a 400 GeV proton beam from the SPS with a total of
2x10^20 protons on target, achievable within five years of data taking. The
proposed detector will reconstruct exclusive HNL decays and measure the HNL
mass. The apparatus is based on existing technologies and consists of a target,
a hadron absorber, a muon shield, a decay volume and two magnetic
spectrometers, each of which has a 0.5 Tm magnet, a calorimeter and a muon
detector. The detector has a total length of about 100 m with a 5 m diameter.
The complete experimental set-up could be accommodated in CERN's North Area.
The discovery of a HNL would have a great impact on our understanding of
nature and open a new area for future research
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