披碱草属3个种的核型研究

首次报道了我国青藏高原3种披碱草局（Elymus）植物的核型，即短芒披减草（E．brachyaristatusA．Love），核型为2n=6x=42=32m＋10sm（4SAT），属2A类型；无芒披碱草（E.submuticus（Keng）Kengf．），核型为2n=6x=42=30m＋12sm（2SAT），属2A类型；硕穗披碱草（E．barystachyus L．B．Cai），核型为2n=6x=42=32m＋10sm（4SAT），属2B类型。

Particle camera and settling chamber measurements at site PC (GeoB11834-3) and SC (GeoB12914-4) off Cape Blanc/Mauritania

Particles sinking out of the euphotic zone are important vehicles of carbon export from the surface ocean. Most of the particles produce heavier aggregates by coagulating with each other before they sink. We implemented an aggregation model into the biogeochemical model of Regional Oceanic Modelling System (ROMS) to simulate the distribution of particles in the water column and their downward transport in the Northwest African upwelling region. Accompanying settling chamber, sediment trap and particle camera measurements provide data for model validation. In situ aggregate settling velocities measured by the settling chamber were around 55 m d**-1. Aggregate sizes recorded by the particle camera hardly exceeded 1 mm. The model is based on a continuous size spectrum of aggregates, characterised by the prognostic aggregate mass and aggregate number concentration. Phytoplankton and detritus make up the aggregation pool, which has an averaged, prognostic and size dependent sinking. Model experiments were performed with dense and porous approximations of aggregates with varying maximum aggregate size and stickiness as well as with the inclusion of a disaggregation term. Similar surface productivity in all experiments has been generated in order to find the best combination of parameters that produce measured deep water fluxes. Although the experiments failed to represent surface particle number spectra, in the deep water some of them gave very similar slope and spectrum range as the particle camera observations. Particle fluxes at the mesotrophic sediment trap site off Cape Blanc (CB) have been successfully reproduced by the porous experiment with disaggregation term when particle remineralisation rate was 0.2 d**-1. The aggregation-disaggregation model improves the prediction capability of the original biogeochemical model significantly by giving much better estimates of fluxes for both upper and lower trap. The results also point to the need for more studies to enhance our knowledge on particle decay and its variation and to the role that stickiness play in the distribution of vertical fluxes.

An integrated approach for earthwork allocation, sequencing and routing

Planning techniques for large scale earthworks have been considered in this article. To improve these activities a “block theoretic” approach was developed that provides an integrated solution consisting of an allocation of cuts to fills and a sequence of cuts and fills over time. It considers the constantly changing terrain by computing haulage routes dynamically. Consequently more realistic haulage costs are used in the decision making process. A digraph is utilised to describe the terrain surface which has been partitioned into uniform grids. It reflects the true state of the terrain, and is altered after each cut and fill. A shortest path algorithm is successively applied to calculate the cost of each haul, and these costs are summed over the entire sequence, to provide a total cost of haulage. To solve this integrated optimisation problem a variety of solution techniques were applied, including constructive algorithms, meta-heuristics and parallel programming. The extensive numerical investigations have successfully shown the applicability of our approach to real sized earthwork problems.

Undamped oscillations of homogeneous collisionless stellar systems

The Lewis (1968) invariant of the time-dependent harmonic oscillator is used to construct exact time-dependent, uniform density solutions of the collisionless Boltzmann equation. The spatially bound solutions are time-periodic.

Estimación del comportamiento productivo y reproductivo de un hato pardo suizo en explotación intensiva en Nicaragua

El presente estudio se realizó basándose en los registros de un hato pardo suizo. Ubicado a 12 grados 15 minutos de latitud, 86 grados 25 minutos de longitud y una elevación de 49 m.s.n.m, con temperatura y humedad relativa promedio en los últimos 12 años de 27 grados Celcius y 70.8% respectivamente y 1250m anuales de precipitación en los últimos 10 años. Las variables en estudio fueron; EPS; EPP; EPPI; PS; IPP: PL;NSC: ML con promedio de 671+/-99 días, 965+/-132 días, 105+/-44dias, 185+/-113 días, 419+/57 días 3445+/-697kg, 1.08+/-1.2ser, 9.6+/-1.6 meses respectivamente. En el ANDEVA para EPS resulto significativo el AM y MN; para la EPP resulto significativo el AN y no significativo el MN; para el IPPI resulto Significativo el AP, no significativo el MP y la variable EP; para el PS e IPP, resulto significativo AP, MP y las variables ML. EP. Las correlaciones lineales entre Ep y NSC; IPPI y ISC, IPPI Y PS, PS y IPPI e IPP, PS e IPP, ML e IPPI, PS IPP, PL y PS, IPP; Il, EP; resultaron significativas con un coeficiente de +0.2815, -067, +0.327, +0.458, +0879, +0.146, +0275, +0.71, +0.247, +0.208, +0.7102, +0.227, respectivamente, las regresiones de NSC con Ep; IPP con EP, PS con IPP con PS; PL con ML y EP; resultaron significativas con valores de coeficiente de +0.327 ser ./año, +5.9 días/año, +0.227 día/días, +0.967 días/días, +430.86 kg/mes de lactancia y +238.3 kg./año respectivamente.

Utilidad de la resonancia magnética en el diagnóstico de apendicitis aguda

Comparar el resultado de la resonancia magnética en el diagnóstico de apendicitis aguda con el patrón de oro (estudio histopatológico o seguimiento clínico del paciente) con el fin de establecer la utilidad de ésta como prueba diagnóstica y poder incluirla dentro del algoritmo de estudio de esta patología cuando hay sospecha clínica y un resultado negativo o dudoso de la ecografía abdominal

Dynamics at infinity and other global dynamical aspects of Shimizu-Morioka equations

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effects of age at first calving, gestation length and dry period on milk yield in a Gyr herd

Relationships of several reproductve traits and milk yield were studied in 716 Gyr cows at Sant'Ana da Serra farm, Mococa, State of São Paulo, a humid tropical climate region. Mean age at first calving was 49.8 +/- 0.4 months, with a coeficient of cariation (C. V.) of 20.8%. Only year of parturition significantly affected age at first calving (P < 0.01). Heritability, estimated from paternal half-sib correlations, was 0.91 +/- 0.20, a value considered unrealistically high. Overall mean gestation length was 287.7 +/- 0.5 days (C. V. = 3.3%) for 419 observations, with month and year of parturition having significant effects. Heritability estimate was 0.30 +/- 0.14. Overall mean dry period for 1.276 observations was 238 +/- 3 days (C. V. = 48%); repeatability estimate was 0.19 +/- 0.06. Estimated annual genetic trend for dry period was -0.6 days, phenotypic trend was 11.5 days, and environmental trend, 12.1 days. Month and year of parturition and cow age had no significant effect on dry period. Highest milk yield was obtained at fourth lactation. The gross correlation between milk yield and gestation period was 0.11, and between previous dry period and subsequent milk yield, 0.16. Normal gestations of 285 to 290 days were associated with higher milk yields. Milk yield increased as dry period advanced from 30 to 390 days, and declined as dry period continued beyond 390 days. Delays in first mating and a more extensive dry period decreased reproductive efficiency in the herd studied.

Comparison of oral administration of lomustine and prednisolone or prednisolone alone as treatment for granulomatous meningoencephalomyelitis or necrotizing encephalitis in dogs

OBJECTIVE: To compare oral administration of lomustine and prednisolone with oral administration of prednisolone alone as treatment for granulomatous meningoencephalomyelitis (GME) or necrotizing encephalitis (NE) in dogs. DESIGN: Retrospective cohort study. ANIMALS: 25 dogs with GME and 18 dogs with NE (diagnosis confirmed in 8 and 5 dogs, respectively). PROCEDURES: Records of dogs with GME or NE were reviewed for results of initial neurologic assessments and clinicopathologic findings, treatment, follow-up clinicopathologic findings (for lomustine-treated dogs), and survival time. Dogs with GME or NE treated with lomustine and prednisolone were assigned to groups 1 (n = 14) and 3 (10), respectively; those treated with prednisolone alone were assigned to groups 2 (11) and 4 (8), respectively. RESULTS: Prednisolone was administered orally every 12 hours to all dogs. In groups 1 and 3, mean lomustine dosage was 60.3 mg/m(2), PO, every 6 weeks. Median survival times in groups 1 through 4 were 457, 329, 323, and 91 days, respectively (no significant difference between groups 1 and 2 or between groups 3 and 4). Within the initial 12 months of treatment, median prednisolone dosage was reduced in all groups; dosage reduction in group 1 was significantly larger than that in group 2 at 6, 9, and 12 months. Combination treatment most frequently caused leukopenia, but had no significant effect on liver enzyme activities. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs with GME and NE, oral administration of lomustine and prednisolone or prednisolone alone had similar efficacy. Inclusion of lomustine in the treatment regimen was generally tolerated well.