AFES Miscellaneous Publication 2013-03

Tracking the growth and development of a new industry is critical to the assessment of its success. Growers, industry support groups, government leaders, educational and research organizations and more use basic statistics on crop production, markets, and growth over time to support and fund activities that promote this industry. Annual statistics also provide an indicator of industry health and can be used to develop models of long-term trends in industry growth. Beginning in 2011, the University of Alaska Fairbanks Agricultural and Forestry Experiment Station began compiling industry statistics. We summarize confidential grower information to provide baseline data that the industry can use to obtain funding, make business decisions, and promote their industry

There are No Causality Problems for Fermi's Two Atom System

A repeatedly discussed gedanken experiment, proposed by Fermi to check Einstein causality, is reconsidered. It is shown that, contrary to a recent statement made by Hegerfeldt, there appears no causality paradoxon in a proper theoretical description of the experiment.Comment: 6 pages, latex, DESY 94-02

Stable quantum systems in anti-de Sitter space: Causality, independence and spectral properties

If a state is passive for uniformly accelerated observers in n-dimensional anti-de Sitter space-time (i.e. cannot be used by them to operate a perpetuum mobile), they will (a) register a universal value of the Unruh temperature, (b) discover a PCT symmetry, and (c) find that observables in complementary wedge-shaped regions necessarily commute with each other in this state. The stability properties of such a passive state induce a "geodesic causal structure" on AdS and concommitant locality relations. It is shown that observables in these complementary wedge-shaped regions fulfill strong additional independence conditions. In two-dimensional AdS these even suffice to enable the derivation of a nontrivial, local, covariant net indexed by bounded spacetime regions. All these results are model-independent and hold in any theory which is compatible with a weak notion of space-time localization. Examples are provided of models satisfying the hypotheses of these theorems.Comment: 27 pages, 1 figure: dedicated to Jacques Bros on the occasion of his 70th birthday. Revised version: typos corrected; as to appear in J. Math. Phy

Nuclearity and Thermal States in Conformal Field Theory

We introduce a new type of spectral density condition, that we call L^2-nuclearity. One formulation concerns lowest weight unitary representations of SL(2,R) and turns out to be equivalent to the existence of characters. A second formulation concerns inclusions of local observable von Neumann algebras in Quantum Field Theory. We show the two formulations to agree in chiral Conformal QFT and, starting from the trace class condition for the semigroup generated by the conformal Hamiltonian L_0, we infer and naturally estimate the Buchholz-Wichmann nuclearity condition and the (distal) split property. As a corollary, if L_0 is log-elliptic, the Buchholz-Junglas set up is realized and so there exists a beta-KMS state for the translation dynamics on the net of C*-algebras for every inverse temperature beta>0. We include further discussions on higher dimensional spacetimes. In particular, we verify that L^2-nuclearity is satisfied for the scalar, massless Klein-Gordon field.Comment: 37 pages, minor correction

The shape of the urine stream — from biophysics to diagnostics

We develop a new computational model of capillary-waves in free-jet flows, and apply this to the problem of urological diagnosis in this first ever study of the biophysics behind the characteristic shape of the urine stream as it exits the urethral meatus. The computational fluid dynamics model is used to determine the shape of a liquid jet issuing from a non-axisymmetric orifice as it deforms under the action of surface tension. The computational results are verified with experimental modelling of the urine stream. We find that the shape of the stream can be used as an indicator of both the flow rate and orifice geometry. We performed volunteer trials which showed these fundamental correlations are also observed in vivo for male healthy volunteers and patients undergoing treatment for low flow rate. For healthy volunteers, self estimation of the flow shape provided an accurate estimation of peak flow rate (+-2%). However for the patients, the relationship between shape and flow rate suggested poor meatal opening during voiding. The results show that self measurement of the shape of the urine stream can be a useful diagnostic tool for medical practitioners since it provides a non-invasive method of measuring urine flow rate and urethral dilation

Estructura de comunidades de arañas en hábitats costeros de un delta mediterráneo (delta del Nestos, NE de Grecia)

Dentro de los ecosistemas mediterráneos la zonación según el hábitat y la ecología de las comunidades de arañas han sido poco estudiadas. Se presenta un primer análisis de las comunidades de arañas en hábitats costeros del Mediterráneo oriental. El área de estudio está constituida por los 250 km2 del delta del Nestos, ubicado en Macedonia oriental, en el noreste de Grecia. Las arañas fueron capturadas mediante trampas de caída (pitfall) en 17 localidades durante el período que oscila entre principios de abril y finales de junio del 2004. Se usaron estimadores no paramétricos para determinar la riqueza de especies y la diversidad alfa. El análisis de ordenación (análisis de redundancia) señaló cuatro grupos de especies de arañas (prados salados, dunas, prados y bosques de planicies aluviales), los cuales se discriminaban claramente a lo largo de gradientes de salinidad del suelo y humedad. En base a estos resultados, se discuten las preferencias de hábitat de estas arañas, incluyendo los primeros comentarios ecológicos sobre varias especies. Palabras clave: Araneae, Macedonia oriental, Preferencia de hábitat, Riqueza de especies, Comunidades de arañas.Habitat zonation and ecology of spider assemblages have been poorly studied in Mediterranean ecosystems. A first analysis of spider assemblages in coastal habitats in the east Mediterranean area is presented. The study area is the 250 km² Nestos Delta, located in East Macedonia in the North–East of Greece. Spiders were caught in pitfall traps at 17 sites from the beginning of April to the end of June 2004. Nonparametric estimators were used to determine species richness and alpha diversity. Ordination analysis (redundancy analysis) indicated four clearly separable spider species groups (salt meadows, dunes, meadows and floodplain forests),along a soil salinity and moisture gradient. Based on these results we discuss the habitat preferences of these spiders and include the first ecological data on several species. Key words: Araneae, East Macedonia, Habitat preference, Species richness, Spider assemblages.Dentro de los ecosistemas mediterráneos la zonación según el hábitat y la ecología de las comunidades de arañas han sido poco estudiadas. Se presenta un primer análisis de las comunidades de arañas en hábitats costeros del Mediterráneo oriental. El área de estudio está constituida por los 250 km2 del delta del Nestos, ubicado en Macedonia oriental, en el noreste de Grecia. Las arañas fueron capturadas mediante trampas de caída (pitfall) en 17 localidades durante el período que oscila entre principios de abril y finales de junio del 2004. Se usaron estimadores no paramétricos para determinar la riqueza de especies y la diversidad alfa. El análisis de ordenación (análisis de redundancia) señaló cuatro grupos de especies de arañas (prados salados, dunas, prados y bosques de planicies aluviales), los cuales se discriminaban claramente a lo largo de gradientes de salinidad del suelo y humedad. En base a estos resultados, se discuten las preferencias de hábitat de estas arañas, incluyendo los primeros comentarios ecológicos sobre varias especies. Palabras clave: Araneae, Macedonia oriental, Preferencia de hábitat, Riqueza de especies, Comunidades de arañas

Construction of wedge-local nets of observables through Longo-Witten endomorphisms. II

In the first part, we have constructed several families of interacting wedge-local nets of von Neumann algebras. In particular, there has been discovered a family of models based on the endomorphisms of the U(1)-current algebra of Longo-Witten. In this second part, we further investigate endomorphisms and interacting models. The key ingredient is the free massless fermionic net, which contains the U(1)-current net as the fixed point subnet with respect to the U(1) gauge action. Through the restriction to the subnet, we construct a new family of Longo-Witten endomorphisms on the U(1)-current net and accordingly interacting wedge-local nets in two-dimensional spacetime. The U(1)-current net admits the structure of particle numbers and the S-matrices of the models constructed here do mix the spaces with different particle numbers of the bosonic Fock space.Comment: 33 pages, 1 tikz figure. The final version is available under Open Access. CC-B