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This article explores the values attributed to the new science of bacteriology in five early stories about bacteriologists: H. G. Wells's 'The Stolen Bacillus' (1894), T. Mullett Ellis's Zalma (1895), W. L. Alden's 'The Purple Death' (1895), Algernon Blackwood's 'Max Hensig' (1907), and Arthur Conan Doyle's 'The Adventure of the Dying Detective' (1913). I argue that the new science becomes a vehicle for anxieties about anarchist terrorism and German militarism. Responding to Martin Willis's (2011) account of the microscope's creative function at the fin de siècle, I suggest that the distinctive qualities of bacteriological science inflect the plot and style of these tales, as well as the nature of their fictional antagonists. These qualities include the magnification of an otherwise invisible threat and the ensuing distortion of the scientist's moral judgement, the discrepancy between microbial size and potency, and German dominance in the field. The formal mechanisms of the texts, their patterns of tension and revelation, are also shown to interact with the new dynamics of bacteriological science and its play of visibility and invisibility. Comparing these texts with contemporaneous advertisements, I point out that the bacteriologist was simultaneously portrayed, to the same audiences, as a vector of threat and a trustworthy authority underwriting new commercial products. This divergence suggests the pliancy of bacteriology's cultural significance and the limited influence of fiction on commercial uses of bacteriology. I argue that such fiction exploits limited public knowledge of the bacteriologist to develop an enduring motif of bacteriology as a moral and political danger. [ABSTRACT FROM AUTHOR]

Portuguese forests have changed in recent years. These changes were mainly boosted by the wildfires that affected a significant percentage of the softwood area. Data from 2015, conveyed by the Portuguese Institute for Nature Conservation and Forests, indicates that hardwoods occupy 70% of the Portuguese forest area. This paper presents the Blackwood (Acacia melanoxylon R. Br.) species potential, focusing on construction applications, based on recent studies performed at the University of Coimbra and SerQ—Forest Innovation and Competences Center. The valuation of Blackwood for structural applications has been considered through the non-destructive and destructive assessment of their mechanical properties as sawn wood. Their potential was also assessed for a more technologically engineered wood product, the glulam. The dynamic modulus of elasticity (MOE) was estimated through the Longitudinal Vibration Method (LVM) and the Transformed Section Method (TSM); the static MOE and bending strength were assessed through a four-point bending test. Agreement was obtained between both approaches. Sawn Portuguese Blackwood showed a density of 647 kg/m3, 13,900 MPa of MOE and a bending strength of 65 MPa (mean values). The glulam beams fabricated with this raw material had improved properties relative to sawn wood, most obviously concerning the bending strength, with an improvement of 29%. This proves the significant ability and potential of these species to be used in construction products with structural purposes like sawn wood and glulam.

En el maquinado de madera, el cambio de las condiciones cinemáticas en el proceso de formación de viruta trae por consecuencia un cambio tanto en los esfuerzos de corte, como en el trabajo específico de corte, es decir, finalmente sobre la potencia de corte. Siendo en la práctica difícil hacer mediciones de esfuerzos de corte o de la energía específica en la línea de producción, el control de la potencia eléctrica de los motores es una realidad. El objetivo de esta investigación es evaluar el efecto del espesor medio de viruta sobre la potencia total de corte y la rugosidad resultante, y estimar el trabajo específico de corte en el proceso de cepillado para madera de acacia melanoxylon (aromo) y sequoia sempervirens (sequoia). Los resultados indicaron una buena correlación entre la potencia de corte y el espesor de viruta, requiriéndose mayor potencia de corte al incrementar la velocidad de avance del material. En cuanto a los resultados de rugosidad superficial, estos reflejaron los cambios del espesor de viruta. Además se obtuvo una mejor calidad superficial con la especie de mayor densidad.In wood machining, the chip formation process consequently brings a change in cutting forces, as well in the specific cutting energy, i.e., finally on the cutting power. Being in practice difficult the measure of cutting forces or the specific energy at the production line, monitoring the electrical output of the power unit is a reality. The aim of this research is to evaluate the change of the mean chip thickness over cutting power and the resulting surface roughness, estimating the specific cutting work on planing process for blackwood and redwood samples. The findings lead to conclude a good correlation between cutting power and chip thickness, requiring the cutting process more power when more feed speed is applied. For the surface roughness, the results presented changes with the chip thickness, and a better surface quality was found with the dense blackwood lumber.

Se estudia el maquinado paralelo a la fibra (dirección 90-0) de aromo australiano, utilizando transductor piezo-eléctrico para monitorear los niveles de emisión acústica (EA) generados durante el corte, considerando el tipo de madera (albura y duramen), y además la relación con la rugosidad superficial (Rz) obtenida. Como resultados se encontró una adecuada relación entre la modificación de las condiciones de maquinado con la emisión acústica, en la cual un incremento de los espesores promedio de viruta se traducen en un mayor consumo energético durante el corte. Asimismo, se encontraron niveles superiores de emisión acústica al cambiar el tipo de madera de albura a duramen. Finalmente, entre rugosidad superficial y emisión acústica se encontró una correlación muy buenaWood machining parallel to the grain (90-0 direction) of Blackwood was performed using piezo-electrical transducer to record the acoustic emission (AE) signals generated during the cut process, considering the type of wood (heartwood and sapwood), and the relationship with surface roughness (Rz). A good relationship it was found between cutting conditions and acoustic emission signals, where an increase of the chip thickness results in a major consumption of cutting energy. Also, it was detected an increase of AE signals with the change of wood type, passing from sapwood to heartwood (increase of density). Finally, a good relationship it was found between surface roughness (Rz) and acoustic emission (AE)

En el maquinado de madera, el cambio de las condiciones cinemáticas en el proceso de formación de viruta trae por consecuencia un cambio tanto en los esfuerzos de corte, como en el trabajo específico de corte, es decir, finalmente sobre la potencia de corte. Siendo en la práctica difícil hacer mediciones de esfuerzos de corte o de la energía específica en la línea de producción, el control de la potencia eléctrica de los motores es una realidad. El objetivo de esta investigación es evaluar el efecto del espesor medio de viruta sobre la potencia total de corte y la rugosidad resultante, y estimar el trabajo específico de corte en el proceso de cepillado para madera de Acacia melanoxylon (aromo) y Sequoia sempervirens (sequoia). Los resultados indicaron una buena correlación entre la potencia de corte y el espesor de viruta, requiriéndose mayor potencia de corte al incrementar la velocidad de avance del material. En cuanto a los resultados de rugosidad superficial, estos reflejaron los cambios del espesor de viruta. Además se obtuvo una mejor calidad superficial con la especie de mayor densidad. Abstract In wood machining, the chip formation process consequently brings a change in cutting forces, as well in the specific cutting energy, i.e., finally on the cutting power. Being in practice difficult the measure of cutting forces or the specific energy at the production line, monitoring the electrical output of the power unit is a reality. The aim of this research is to evaluate the change of the mean chip thickness over cutting power and the resulting surface roughness, estimating the specific cutting work on planing process for blackwood and redwood samples. The findings lead to conclude a good correlation between cutting power and chip thickness, requiring the cutting process more power when more feed speed is applied. For the surface roughness, the results presented changes with the chip thickness, and a better surface quality was found with the dense blackwood lumber.

An essay is presented on the role of religion, romanticism, and evangelicalism in the late eighteenth and early nineteenth century, which was reflected in the works of Scottish writers. An analysis of the peom "The Course of Time" by Robert Pollok is presented. Pollok's works were influenced by religious environment, Calvinism, and talks about his connection with Covenanters. Scottish romanticism has portrayed the connection between religion and Scottish writing.

Context: Australian blackwood ( Acacia melanoxylon), is a fast-growing, high-quality, appearance-grade timber species native to eastern Australia. Some of its key wood properties are percentage heartwood, heartwood colour, basic density, wood stiffness and green moisture content. Variation in these properties affects log value, processing and marketing. Aims: This study aims to understand how genetics and environment affect these wood properties. Methods: Stem cores were taken from 16 open-pollinated blackwood families from the island of Tasmania, Australia, which were planted across three 18-year-old progeny trials. Results: Significant effects of genetics, environment and their interaction (GxE) were found for many of the wood properties examined. Both broad-scale and local environmental effects were apparent, with local effects associated with competition and/or allelopathy from a Eucalyptus globulus nurse crop present in one trial. No significant correlation of growth rate (i.e. stem diameter) with wood properties was detected at the family level apart from a positive relationship with heartwood width. At the phenotypic level, there were many significant correlations including growth rate with heartwood width, but not with basic density, or wood stiffness measured as standing tree time of flight. Faster growing trees had yellower heartwood while trees with higher basic and green densities tended to have darker, redder and less yellow heartwood. Conclusion: Both genetic and environment factors affect key wood properties of Australian blackwood, but in most cases these effects were independent of growth rate. [ABSTRACT FROM AUTHOR]

Wood machining parallel to the grain (90-0 direction) of Blackwood was performed using piezo-electrical transducer to record the acoustic emission (AE) signals generated during the cut process, considering the type of wood (heartwood and sapwood), and the relationship with surface roughness (Rz). A good relationship it was found between cutting conditions and acoustic emission signals, where an increase of the chip thickness results in a major consumption of cutting energy. Also, it was detected an increase of AE signals with the change of wood type, passing from sapwood to heartwood (increase of density). Finally, a good relationship it was found between surface roughness (Rz) and acoustic emission (AE). [ABSTRACT FROM AUTHOR]

This study investigated the feasibility of silvicultural intervention in Acacia melanoxylon (R. Br.) plantations grown with Pinus radiata (D. Don) nurse crops, to improve stem form and growth rate. The objective of the study was to evaluate silvicultural options for managing a nurse-crop to avoid suppression but improve stem form of A. melanoxylon. Using a 5-year-old A. melanoxylon–P. radiata plantation, various levels of form pruning of the A. melanoxylon were tested by removing prescribed proportions of leaf area from treatment trees. In addition, a range of thinning treatments was imposed on the nurse-crop. The effects of these treatments on A. melanoxylon growth rate, stem form, rate of crown development, and canopy light environment were assessed.Altering the canopy structure of the plantations by thinning the P. radiata nurse-crop had a positive effect on A. melanoxylon diameter growth. However, less desirable changes were also evident following thinning of the P. radiata, such as reduced height increment, loss of dominance and a greater incidence of large branches in A. melanoxylon trees. Appreciable changes in the light environment of the A. melanoxylon crowns occurred only after more than 50% of P. radiata trees were removed. Crowns of A. melanoxylon trees pruned of 50% of their foliage area took 12 months to recover to pre-pruning foliage area levels. Form pruning A. melanoxylon significantly reduced growth when 50% of foliage area was removed.Improvements in form by pruning were transient in nature, highlighting the need for on-going, low-intensity form pruning treatment to establish good stem form. The rapid deterioration in form after heavy thinning of the nurse-crop indicated the need to establish form before reducing nurse-crop competition. [Copyright &y& Elsevier]

Saplings of blackwood (Acacia melanoxylon) responded positively to release from competing young Eucalyptus obliqua in native forests of north-west Tasmania. In the treated area, 6 years after establishment of the regrowth forest on a cleared and burned seedbed, the young emergent eucalypts were culled by stem injection of herbicide. The dense sub-canopy (principally Pomaderris apetala) was also removed in two gap treatments (3.6 and 7.2 m diameter); each treatment applied to 27 single tree plots.During the 6 years following silvicultural treatment, periodic annual increment (PAI) of blackwood stem diameter increased from 0.8 cm per year in the untreated area to 1.4 cm per year where eucalypts (only) had been removed. The additional removal of the sub-canopy increased blackwood PAI (diameter) to 1.6 cm per year in the small gaps and 2.1 cm per year in the larger gaps. These are statistically significant increases of 75, 100 and 160%, respectively.However, the larger sub-canopy gaps produced heavier, broader blackwood crowns, increased branch size and retention and reduced the length of branch-free bole. Maximum blackwood diameter and volume gains were therefore achieved at the expense of tree form and future log quality. In contrast, the removal of competing eucalypts (only) produced a smaller stem diameter response, but the remaining dense sub-canopy maintained excellent stem form and clear bole. [Copyright &y& Elsevier]

Portuguese forests have changed in recent years. These changes were mainly boosted by the wildfires that affected a significant percentage of the softwood area. Data from 2015, conveyed by the Portuguese Institute for Nature Conservation and Forests, indicates that hardwoods occupy 70% of the Portuguese forest area. This paper presents the Blackwood (Acacia melanoxylon R. Br.) species potential, focusing on construction applications, based on recent studies performed at the University of Coimbra and SerQ—Forest Innovation and Competences Center. The valuation of Blackwood for structural applications has been considered through the non-destructive and destructive assessment of their mechanical properties as sawn wood. Their potential was also assessed for a more technologically engineered wood product, the glulam. The dynamic modulus of elasticity (MOE) was estimated through the Longitudinal Vibration Method (LVM) and the Transformed Section Method (TSM); the static MOE and bending strength were assessed through a four-point bending test. Agreement was obtained between both approaches. Sawn Portuguese Blackwood showed a density of 647 kg/m3, 13,900 MPa of MOE and a bending strength of 65 MPa (mean values). The glulam beams fabricated with this raw material had improved properties relative to sawn wood, most obviously concerning the bending strength, with an improvement of 29%. This proves the significant ability and potential of these species to be used in construction products with structural purposes like sawn wood and glulam. [ABSTRACT FROM AUTHOR]