IFOAM Training Manual: Training Manual for Organic Agriculture in the Humid Tropics

The first IFOAM Training Manual for Organic Agriculture in the Tropics (the Basic Manual) was published in 2004. The Research Institute of Organic Agriculture (FiBL) together with partners of the organic movement in the Tropics were commissioned by IFOAM to complete two new training manuals that build on the Basic Manual. The new IFOAM training manuals address the two basic climatic zones of the Tropics, the Arid and Semi-Arid Tropics, and the Humid Tropics. For both new manuals, already existing material was collected, screened and condensed into comprehensive training manuals. Additionally, a large number of farmers, trainers and scientists were asked for their experience. Partner institutions from the Tropics actively collaborated in the development of the manuals. The partners of the manual for the Arid and Semi-Arid Tropics are from Asia (India), Africa (Senegal and Tunisia) and Latin America (Chile). The training manuals contain case studies of organic farming systems, describe successful organic marketing initiatives and offer guidelines for the main crops of the Tropics. With the informative text, transparencies and didactical recommendations the training manuals offer a resource basis for trainers with the idea of encouraging individual adaptation and further development of the material according to need. The training manuals are available on separate CDs in English, French and Spanish. The training manuals were commissioned by IFOAM and funded through its program IFOAM-GROWING ORGANIC II (I-GO II). The Research Institute of Organic Agriculture (FiBL) and the Swiss Import Promotion Programme (SIPPO) provided co-funding

Properties of pedestrians walking in line: Stepping behavior

In human crowds, interactions among individuals give rise to a variety of self-organized collective motions that help the group to effectively solve the problem of coordination. However, it is still not known exactly how humans adjust their behavior locally, nor what are the direct consequences on the emergent organization. One of the underlying mechanisms of adjusting individual motions is the stepping dynamics. In this paper, we present first quantitative analysis on the stepping behavior in a one-dimensional pedestrian flow studied under controlled laboratory conditions. We find that the step length is proportional to the velocity of the pedestrian, and is directly related to the space available in front of him, while the variations of the step duration are much smaller. This is in contrast with locomotion studies performed on isolated pedestrians and shows that the local density has a direct influence on the stepping characteristics. Furthermore, we study the phenomena of synchronization -walking in lockstep- and show its dependence on flow densities. We show that the synchronization of steps is particularly important at high densities, which has direct impact on the studies of optimizing pedestrians flow in congested situations. However, small synchronization and antisynchronization effects are found also at very low densities, for which no steric constraints exist between successive pedestrians, showing the natural tendency to synchronize according to perceived visual signals.Comment: 8 pages, 5 figure

Studying the ω\omega properties in pA collisions via the ω→π0γ\omega{\to}\pi^0\gamma decay

Within transport calculations we study the production and decay of $\omega$-mesons in $pA$ reactions at COSY energies including elastic and inelastic ${\omega}N$ rescattering, the $\omega{\to}\pi^0\gamma$ Dalitz decay as well as $\pi^0 N$ rescattering. The resulting invariant $\pi^0 \gamma$ mass distributions indicate that in-medium modifications of the $\omega$-meson may be observed experimentally.Comment: 5 pages, espcrc2-style, including 5 ps-figure

The Berry-Keating operator on L^2(\rz_>, x) and on compact quantum graphs with general self-adjoint realizations

The Berry-Keating operator H_{\mathrm{BK}}:= -\ui\hbar(x\frac{ \phantom{x}}{ x}+{1/2}) [M. V. Berry and J. P. Keating, SIAM Rev. 41 (1999) 236] governing the Schr\"odinger dynamics is discussed in the Hilbert space L^2(\rz_>, x) and on compact quantum graphs. It is proved that the spectrum of $H_{\mathrm{BK}}$ defined on L^2(\rz_>, x) is purely continuous and thus this quantization of $H_{\mathrm{BK}}$ cannot yield the hypothetical Hilbert-Polya operator possessing as eigenvalues the nontrivial zeros of the Riemann zeta function. A complete classification of all self-adjoint extensions of $H_{\mathrm{BK}}$ acting on compact quantum graphs is given together with the corresponding secular equation in form of a determinant whose zeros determine the discrete spectrum of $H_{\mathrm{BK}}$. In addition, an exact trace formula and the Weyl asymptotics of the eigenvalue counting function are derived. Furthermore, we introduce the "squared" Berry-Keating operator $H_{\mathrm{BK}}^2:= -x^2\frac{ ^2\phantom{x}}{ x^2}-2x\frac{ \phantom{x}}{ x}-{1/4}$ which is a special case of the Black-Scholes operator used in financial theory of option pricing. Again, all self-adjoint extensions, the corresponding secular equation, the trace formula and the Weyl asymptotics are derived for $H_{\mathrm{BK}}^2$ on compact quantum graphs. While the spectra of both $H_{\mathrm{BK}}$ and $H_{\mathrm{BK}}^2$ on any compact quantum graph are discrete, their Weyl asymptotics demonstrate that neither $H_{\mathrm{BK}}$ nor $H_{\mathrm{BK}}^2$ can yield as eigenvalues the nontrivial Riemann zeros. Some simple examples are worked out in detail.Comment: 33p

Discovery of a [WO] central star in the planetary nebula Th 2-A

% context About 2500 planetary nebulae are known in our Galaxy but only 224 have central stars with reported spectral types in the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (Acker et al. 1992; Acker et al. 1996) % aims We have started an observational program aiming to increase the number of PN central stars with spectral classification. % methods By means of spectroscopy and high resolution imaging, we identify the position and true nature of the central star. We carried out low resolution spectroscopic observations at CASLEO telescope, complemented with medium resolution spectroscopy performed at Gemini South and Magellan telescopes. % results As a first outcome of this survey, we present for the first time the spectra of the central star of the PN Th 2-A. These spectra show emission lines of ionized C and O, typical in Wolf-Rayet stars. % conclusions We identify the position of that central star, which is not the brightest one of the visual central pair. We classify it as of type [WO 3]pec, which is consistent with the high excitation and dynamical age of the nebula.Comment: 3 pages and 2 figures. Paper recommended for publication in A&

Inverse Eigenvalue Problems for Perturbed Spherical Schroedinger Operators

We investigate the eigenvalues of perturbed spherical Schr\"odinger operators under the assumption that the perturbation $q(x)$ satisfies $x q(x) \in L^1(0,1)$. We show that the square roots of eigenvalues are given by the square roots of the unperturbed eigenvalues up to an decaying error depending on the behavior of $q(x)$ near $x=0$. Furthermore, we provide sets of spectral data which uniquely determine $q(x)$.Comment: 14 page

Bound states in point-interaction star-graphs

We discuss the discrete spectrum of the Hamiltonian describing a two-dimensional quantum particle interacting with an infinite family of point interactions. We suppose that the latter are arranged into a star-shaped graph with N arms and a fixed spacing between the interaction sites. We prove that the essential spectrum of this system is the same as that of the infinite straight "polymer", but in addition there are isolated eigenvalues unless N=2 and the graph is a straight line. We also show that the system has many strongly bound states if at least one of the angles between the star arms is small enough. Examples of eigenfunctions and eigenvalues are computed numerically.Comment: 17 pages, LaTeX 2e with 9 eps figure

Quantum Effects for the Dirac Field in Reissner-Nordstrom-AdS Black Hole Background

The behavior of a charged massive Dirac field on a Reissner-Nordstrom-AdS black hole background is investigated. The essential self-adjointness of the Dirac Hamiltonian is studied. Then, an analysis of the discharge problem is carried out in analogy with the standard Reissner-Nordstrom black hole case.Comment: 18 pages, 5 figures, Iop styl

Essential self-adjointness in one-loop quantum cosmology

The quantization of closed cosmologies makes it necessary to study squared Dirac operators on closed intervals and the corresponding quantum amplitudes. This paper proves self-adjointness of these second-order elliptic operators.Comment: 14 pages, plain Tex. An Erratum has been added to the end, which corrects section

Comparison of Chlamydia antigen and AD-like pathology in the brains of BALB/c mice following intranasal infection with Chlamydia muridarum or Chlamydia pneumoniae

Previous research indicates BALB/c mice inoculated with Chlamydia pneumoniae (Cpn) demonstrated AD-like pathology which suggests that this mouse model is valid for studying the pathogenesis implicated in Alzheimer’s disease (AD). Studies have demonstrated that Chlamydia trachomatis (Ctr) can disseminate from its primary site of infection and plays a major role in the induction of reactive arthritis. The objectives of this lab are: (1) to identify and localize Chlamydia antigens in the brains of BALB/c mice infected with C. muridarum and (2) to determine if infection with C. muridarum induces AD-like pathology comparable to Cpn. Using mouse adapted respiratory isolates of C. muridarum, we investigated whether C. muridarum disseminated from the respiratory tract to the brain. Mice were intranasally infected with plaqued C small Weiss (CSW) or plaqued mouse pneumonitis Weiss (MoPn Weiss). Brain tissue was isolated at 2 months post-infection. Serial sections from brains infected mice were analyzed for amyloid or Chlamydia antigens. Preliminary analysis of brain tissue demonstrated no detectable difference in C. muridarum antigen between mice receiving 1 x105 IFU and mice receiving 1 x101 IFU, whereas a small but detectable difference was identified in amyloid-specific labeling between these two experimental groups. In contrast, prominent Chlamydia-specific labeling was identified in the brains of Cpn-infected mice as well as substantial amyloid deposition at 2 months p.i.. These data suggest that, relative to Cpn AR-39 infection, C. muridarum infection is a weaker stimulus for inflammation, resulting in decreased amyloid deposition in the brains of BALB/c mice