Smernice za tehnike izboljšanja tal v vinogradih

Guidelines for soil restoration in vineyard (in Slovenian language

Heartwood and sapwood variation in Acacia melanoxylon R. Br. trees in Portugal

The development of heartwood and sapwood in blackwood ( Acacia melanoxylon R. Br.) was studied in a total of 20 trees with a 40-cm-diameter class sampled over four stands in northern Portugal at harvest for timber production. Stem discs with 5-cm thickness were taken at different height levels (stem base and 5, 15, 35, 50, 65, 75, 85 and 90 per cent of total height). Crosssectional area and heartwood area were measured by image analysis. Heartwood represented a substantial part of the trees and within the tree it attained on average 81 per cent of total height, and represented 69, 62, 58 and 44 per cent of the stem cross-sectional area, respectively, at 5, 35, 50 and 65 per cent of total tree height. The heartwood followed closely the stem wood profi le both axially and radially. Estimation of heartwood dimensions from external wood diameters (either over or under bark) was possible using a linear model, which had a very high correlation coeffi cient ( R 2 = 0.97). The sapwood radial width showed a very small variation within and between trees and maintained a constant value of 31 mm up to ∼ 65 per cent of tree height. No site infl uence was found for the heartwood development and the between-tree variation was small. The species and the sampled individuals in Portugal showed potential for the diversifi cation of forest production and increasing the industrial supply of a valuable timber hardwoodinfo:eu-repo/semantics/publishedVersio

Natural durability assessment of thermo-modified young wood of Eucalyptus

This study focuses on the effect on wood strength and natural durability of Eucalyptus globulus and Eucalyptus botryoides when subjected to heat treatments with low energy consumption. The objective was to improve the wood durability, without negatively impacting the strength properties. Six-year-old trees from Eucalyptus globulus and Eucalyptus botryoides were used. The samples were heat treated for 4 h conditioned to very low oxygen availability. A field test for assessing the resistance to termites and fungal degradation was conducted according to EN 252:1989/ AC1:1989 Inspections were made every six months for 3 years. All the samples of Eucalyptus globulus showed signs of termite and microorganisms attack, most showing extensive galleries. Eucalyptus botryoides wood showed no sign of termite attack and only few traces of microrganisms presence. The wood bending strength was smaller upon thermal treatment for both species, decreasing 3.8% and 4.8% for Eucalyptus globulus and Eucalyptus botryoides, respectively. Overall the results are promising regarding some common utilizations, mainly floor coverings, decks, doors and door and window frames, fences (only for Eucalyptus botryoides), decorative arbors and pergolas (only for Eucalyptus botryoides) but excluding structural beams for building roofs or bridges due to the fragility of the wood treated thermally towards impactsinfo:eu-repo/semantics/publishedVersio

Computational methods for rational screening and engineering of enzyme properties

2010/2011State of the art computational thechniques were applied to several current research toppics in biocatalysis such as substrate promiscuity, reaction promiscuity and high throughput mutant generation and screening. The studied subjects are of great interest to industrial biocatalysis nowadays and can find large application for rational redesign of inefficient biocatalysts and fast substrate engineering and screening. The overall work can be devided into three principal areas, i.e. understanding catalytic mechanisms, description of enzyme-substrate interactions and integration of available computational methods for the development of a novel authomatized tool for enzyme engineering. In each of these areas, the goal has been to test the existing methodologies as well as the development of new descriptors and ready to use strategies.XXIV Ciclo198

Stem and wood characterization of Acacia melanoxylon as an introduced species in Europe

Stem and wood characterization of Acacia melanoxylon as an introduced species in Europeinfo:eu-repo/semantics/publishedVersio

Within-tree and between-tree variation of wood density components in cork oak trees in two sites in Portugal

The axial and radial variation of wood density was studied using microdensitometry in cork oaks ( Quercus suber ) in two sites in Portugal. The observations were made in mature trees under cork production and in juvenile trees before the fi rst cork extraction, at three height levels (stem base, 1.3 m and before stem bifurcation). The cork oak wood revealed a very high mean density (0.884 – 1.068 g cm 3 ). Differences between earlywood and latewood were small (0.866 and 1.061 g cm 3 , respectively). Latewood corresponded on average to 61 per cent of the total. The variation of density between trees was statistically highly signifi cant, but no differences were found between the two sites. The within-tree axial variation was negligible but the radial direction within a cross-section was one of the main origins of variation of the density components (18 per cent of the total variation). The density decreased from pith to cambium and this radial variation corresponded to 19 – 24 per cent of the total variation of wood density. Overall, the magnitude of density variations between and within cork oaks was small and an advantageous factor for their use for quality wood productsinfo:eu-repo/semantics/publishedVersio

Improved Video Advertising Inventory Tracking and New Opportunity Definition

This disclosure provides for a method for tracking and reporting streams and pods in video advertising inventory sharing. The present disclosure can provide for enhanced visibility into inventory allocation. The enhanced visibility can include populating data structures with various dimensions associated with video content streams. The data structures can be obtained by an inventory share pipeline. The inventory share pipeline can aggregate data associated with various advertisement slots to generate an output data structure comprising an inventory share report. The inventory share report can include a stream count and a pod count associated with the respective party of the inventory share agreement. For instance, the partner and the host can visualize a number of streams (e.g., continuous video content stream) or pod count (e.g., a number of advertisement pods within a stream) that were allocated to the respective party. Thus, the parties are provided with a more granular view of how the percentage of content slots were distributed (e.g., by stream or pod opposed to a percentage of the entire available content slots). Additionally, the present disclosure provides for a new definition of inventory share opportunity. Unlike existing methods that determine a rough estimate of inventory share opportunities based on measured advertisement impressions, the present disclosure provides for a temporally based measure of inventory shares. For instance, the present disclosure utilizes a predetermined standard duration of an opportunity and divides pods based on the temporal duration to determine a number of inventory share opportunities

Cerne e borne - factores de variação da qualidade tecnológica das árvores

Congresso Florestal Nacional: A floresta e as gentes - Actas das ComunicaçõesO lenho do tronco das árvores inclui duas zonas com características diferentes: o cerne e o borne, respectivamente no interior e exterior. A partir de uma certa idade ocorre a formação de cerne por transformação do borne. Neste processo as células de parênquima do borne morrem, ocorre acumulação de extractivos e deixa de haver condução. Como consequência, o cerne apresenta maior durabilidade natural, menor permeabilidade e, em geral, uma cor mais escura, ao contrário do borne. Para a produção de pasta para papel, a presença de cerne constitui uma desvantagem, enquanto que para produtos de madeira maciça, o cerne é um factor de valorização, especialmente em aplicações de exterior ou com alto valor estético. Em Portugal, o eucalipto e o pinheiro bravo são duas espécies importantes, respectivamente como matéria-prima para pasta para papel e para serração e nas quais o cerne constitui uma parte importante do tronco na idade de abate das árvores

Variação das componentes da densidade entre e dentro das árvores de Quercus faginea

Utilizando a técnica de microdensitometria por raios-x, foram estudados padrões de variação axial e radial da densidade, e suas componentes, da madeira de Quercus faginea. O trabalho foi efectuado com base em amostras de madeira colhidas em 4 níveis de altura no tronco (Base, Dap, 3,4m e 5,5m), de 10 árvores adultas localizadas no Nordeste Transmontano. A madeira de Quercus faginea revelou-se muito densa (densidade média do anel = 0,859 g.cm-3), com uma considerável variabilidade dentro dos anéis (densidade média lenho inicial = 0,698 g.cm-3; densidade média lenho final = 0,927 g.cm-3) em que o lenho final representa quase 70% do total do anel de crescimento. A variação entre árvores foi sempre estatisticamente altamente significativa, representando entre 8,2% e 12,9% da variação total. Relativamente aos padrões de variação dentro das árvores, verificou-se que a variação radial (sentido medula/câmbio) é considerável, e bastante superior à axial (sentido base/topo), sendo a primeira responsável por 19,2% a 30,4% da variação total e traduzida por uma tendência de decréscimo da densidade da medula para o câmbio. No que refere à variação axial, a tendência é para um ligeiro decréscimo da densidade da base para o topo, explicando entre 5,8% a 6,8% da variação total