Selection and Agronomic Characterization of Leucaena spp. Genotypes for Cold Tolerance. I. Dry Matter Yield.

Biotypes of Leucaena spp (56) were evaluated in order to identify those with tolerance to low temperature and with desirable characteristics as a forage crop. Selection was done at two phases. Phase I: 92 days old seedlings (n=2800) were subjected at two temperatures treatments during 14 hours: T1= -8 °C and T2= -3 °C. Selection criteria was established as 50% of live leaves remained after treatments were applied. Phase II: Plants that survived phase I were planted at field conditions and agronomic characteristics were measured. Seventeen plants were selected from eleven different biotypes, resulting one from T1 and the rest from T2. Three plants showed good agronomic adaptation and greater chilling tolerance. Only one plant maintained live stem and meristematic tissue after a -8.8 °C freeze occurrence . Plants N° 2, 3, 5, 6, 8, 9, 10, 11, 12, 13, 15 and 16 were the most productive (Dry matter production)

Nominal Unification of Higher Order Expressions with Recursive Let

A sound and complete algorithm for nominal unification of higher-order expressions with a recursive let is described, and shown to run in non-deterministic polynomial time. We also explore specializations like nominal letrec-matching for plain expressions and for DAGs and determine the complexity of corresponding unification problems.Comment: Pre-proceedings paper presented at the 26th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2016), Edinburgh, Scotland UK, 6-8 September 2016 (arXiv:1608.02534

Response of \u3cem\u3eAxonopus catarinensis\u3c/em\u3e and \u3cem\u3eArachis pintoi\u3c/em\u3e to Shade Conditions

In the north-east of Argentina, there are more than 100,000 hectares of silvopastoral systems where trees, forages and livestock are combined with the goal to diversify income, reduce financial risk, obtain more profit and enhance environmental benefit (Cubbage et al. 2013). The rapid adoption of this production system by farmers has generated high demand for information on shade tolerant grass and legume forage species. Axonopus catarinensis is a native grass from Itajai Vally (Brazil) that was introduced to the north-east of Argentina 10 years ago; whereas Arachis pintoi is a sub-tropical legume (also native to Brazil) adapted to acid soils and tolerant of medium levels of shade (Fisher and Cruz 1994). Visual observation of these species in the field indicated high yields and acceptable tolerance to shade. A trial was subsequently carried out with the aim to quantify dry matter yield and nutritive quality of the species under different levels of shade for silvopastoral use

An AC susceptometer for the characterization of large, bulk superconducting samples

The main purpose of this work was to design, develop and construct a simple, low-cost AC susceptometer to measure large, bulk superconducting samples (up to 32 mm in diameter) in the temperature range 78-120 K. The design incorporates a double heating system that enables a high heating rate (25 K/hour) while maintaining a small temperature gradient (< 0.2 K) across the sample. The apparatus can be calibrated precisely using a copper coil connected in series with the primary coil. The system has been used successfully to measure the temperature dependence of the AC magnetic properties of entire RE-Ba-Cu-O [(RE)BCO] bulk superconducting domains. A typical AC susceptibility measurement run from 78 K to 95 K takes about 2 hours, with excellent temperature resolution (temperature step ~ 4 mK) around the critical temperature, in particular.Comment: 25 pages, 7 figures. Accepted for publication in Measurement Science and Technolog

Report of the LHC Computing Grid Project. RTAG 12: Collaborative Tools

This document is the final report of the LHC Computing Grid (LCG) Project's Requirements and Technical Assessment Group (RTAG 12) on Collaborative Tools. It presents a summary of the requirements of the LHC collaborations for Collaborative Tools, assesses the current status of those tools in common use, discusses likely relevant future development, and provides recommendations for action by the LCG, the collaborations, and CERN for the immediate and long-term future. The requirements and assessments were assembled from formal and informal interactions between members of the RTAG, representatives of the LHC collaborations, CERN IT, and experts in the field of Collaborative Tools

Toward a global description of the nucleus-nucleus interaction

Extensive systematization of theoretical and experimental nuclear densities and of optical potential strengths exctracted from heavy-ion elastic scattering data analyses at low and intermediate energies are presented.The energy-dependence of the nuclear potential is accounted for within a model based on the nonlocal nature of the interaction.The systematics indicate that the heavy-ion nuclear potential can be described in a simple global way through a double-folding shape,which basically depends only on the density of nucleons of the partners in the collision.The poissibility of extracting information about the nucleon-nucleon interaction from the heavy-ion potential is investigated.Comment: 12 pages,12 figure

Efecto del fuego sobre la fauna de invertebrados de un pastizal al noroeste de Corrientes

Con el fin de evaluar el efecto del fuego sobre la fauna de invertebrados en un pastizal con predominio de Andropogon lateris y Sorghastrum agrostoides, en el Noroeste de la provincia de Corrientes, Argentina, se realizaron relevamientos y descripción de su comportamiento pre y post quema en el área de estudio. Entre 1998 y 2000, se aplicaron al pastizal diferentes frecuencias de quema, en un diseño en bloques al azar con tres repeticiones, evaluándose periódicamente la cantidad y diversidad de la fauna de invertebrados. Se realizó análisis multivariante de conglomerados jerárquicos, con distancia euclídea, para evaluar el comportamiento de la fauna estudiada por oportunidad de muestreo. Se realizó análisis de la variancia por grupo taxonómico y posteriormente la prueba de Tukey para separación de medias. Tanto en los muestreos de prequema como los de postquema los grupos de invertebrados presentes fueron en su mayoría de las clases: Insecta, Arachnida (Aranea y Acarina), Crustacea, Miriápoda, Annelida, Nemátoda y Molusca

An MPEG-7 scheme for semantic content modelling and filtering of digital video

Abstract Part 5 of the MPEG-7 standard specifies Multimedia Description Schemes (MDS); that is, the format multimedia content models should conform to in order to ensure interoperability across multiple platforms and applications. However, the standard does not specify how the content or the associated model may be filtered. This paper proposes an MPEG-7 scheme which can be deployed for digital video content modelling and filtering. The proposed scheme, COSMOS-7, produces rich and multi-faceted semantic content models and supports a content-based filtering approach that only analyses content relating directly to the preferred content requirements of the user. We present details of the scheme, front-end systems used for content modelling and filtering and experiences with a number of users

Study of coupling loss on bi-columnar BSCCO/Ag tapes by a.c. susceptibility measurements

Coupling losses were studied in composite tapes containing superconducting material in the form of two separate stacks of densely packed filaments embedded in a metallic matrix of Ag or Ag alloy. This kind of sample geometry is quite favorable for studying the coupling currents and in particular the role of superconducting bridges between filaments. By using a.c. susceptibility technique, the electromagnetic losses as function of a.c. magnetic field amplitude and frequency were measured at the temperature T = 77 K for two tapes with different matrix composition. The length of samples was varied by subsequent cutting in order to investigate its influence on the dynamics of magnetic flux penetration. The geometrical factor $\chi_0$ which takes into account the demagnetizing effects was established from a.c. susceptibility data at low amplitudes. Losses vs frequency dependencies have been found to agree nicely with the theoretical model developed for round multifilamentary wires. Applying this model, the effective resistivity of the matrix was determined for each tape, by using only measured quantities. For the tape with pure silver matrix its value was found to be larger than what predicted by the theory for given metal resistivity and filamentary architecture. On the contrary, in the sample with a Ag/Mg alloy matrix, an effective resistivity much lower than expected was determined. We explain these discrepancies by taking into account the properties of the electrical contact of the interface between the superconducting filaments and the normal matrix. In the case of soft matrix of pure Ag, this is of poor quality, while the properties of alloy matrix seem to provoke an extensive creation of intergrowths which can be actually observed in this kind of samples.Comment: 20 pages 11 figure, submitted to Superconductor Science and Technolog