Variability in the anatomy and density of Eucalyptus globulus wood: preliminary analysis of the effect of provenance, soil and age

El objetivo del trabajo fue analizar la variabilidad que establecen las procedencias, suelo y edades de cosecha en la anatomía y densidad de la madera de Eucalyptus globulus Labil. implantados comercialmente en el sudeste de la Provincia de Buenos Aires, Argentina. Se seleccionaron 23 árboles de 3 procedencias (Valdivia, Angol y Portuguesa), 4 categorías de suelos (de muy apto a no apto) y 2 rangos de edades de cosecha (10-11 y 14-15 años). Los árboles de la procedencia Portuguesa registraron los mayores valores de altura y diámetro, mientras que los suelos y edad no tuvieron influencia. La calidad de la madera producida en términos de biometría de fibras y vasos, tiende a ser diferente según estos tres factores, mientras que las diferencias en densidad básica de la madera no fueron importantes desde el punto de vista tecnológico en el rango de edad de 14-15 años. La procedencia Portuguesa presentó las fibras más largas (908 ± 230 μm) y el menor espesor de pared (2,05 ± 0,6 μm), los vasos fueron intermedios en número y diámetro (11 ± 4 /mm² y 81 ± 30 μm). El suelo poco apto fue el que registró la mejor combinación de valores de fibras y vasos (mayor longitud de fibras y espesor de pared, con bajo número de vasos de diámetro intermedio). Los árboles muestreados a mayor edad produjeron madera con mayor longitud de fibras, espesor de pared y diámetro de vasos. Tomando la densidad como índice de calidad tecnológica para diferentes industrias (aserrado-papel), la madera producida puede considerarse un material relativamente homogéneo (0,547 ± 0,05 g/cm3).The aim of the work was to analyze the variability established by provenances, soil and harvest ages in the anatomy and density of Eucalyptus globulus Labil. commercially implanted in the southeast of the province of Buenos Aires, Argentina. We selected 23 trees from 3 provenances (Valdivia, Angol and Portuguesa), 4 soil categories (from very suitable to unsuitable) and 2 ranges of harvest ages (10-11 and 14-15 years). The trees of the Portuguese provenance recorded the highest values of height and diameter, while the soils and age had no influence. The quality of the wood produced in terms of fiber and vessel biometrics tends to be different according to these three factors, while the differences in the basic density of the wood were not important from the technological point of view in the age range of 14 -15 years. The Portuguese provenance presented the longest fibers (908 ± 230 μm) and the lowest wall thickness (2.05 ± 0.6 μm), the vessels were intermediate in number and diameter (11 ± 4 / mm2 and 81 ± 30 μm). The least suitable soil was the one that recorded the best combination of fiber and vessel values (greater fiber length and wall thickness, with fewer intermediate diameter vessels). The trees sampled at a older age produced wood with greater fiber length, wall thickness and vessel diameter. The growth of trees (height and diameter) did not correlate with the quality of wood produced. Taking density as an index of technological quality for different industries (sawing-paper), the wood produced can be considered a relatively homogeneous material (0.557 ± 0.05 g / cm³)

Variability in the anatomy and density of Eucalyptus globulus wood: preliminary analysis of the effect of provenance, soil and age

El objetivo del trabajo fue analizar la variabilidad que establecen las procedencias, suelo y edades de cosecha en la anatomía y densidad de la madera de Eucalyptus globulus Labil. implantados comercialmente en el sudeste de la Provincia de Buenos Aires, Argentina. Se seleccionaron 23 árboles de 3 procedencias (Valdivia, Angol y Portuguesa), 4 categorías de suelos (de muy apto a no apto) y 2 rangos de edades de cosecha (10-11 y 14-15 años). Los árboles de la procedencia Portuguesa registraron los mayores valores de altura y diámetro, mientras que los suelos y edad no tuvieron influencia. La calidad de la madera producida en términos de biometría de fibras y vasos, tiende a ser diferente según estos tres factores, mientras que las diferencias en densidad básica de la madera no fueron importantes desde el punto de vista tecnológico en el rango de edad de 14-15 años. La procedencia Portuguesa presentó las fibras más largas (908 ± 230 μm) y el menor espesor de pared (2,05 ± 0,6 μm), los vasos fueron intermedios en número y diámetro (11 ± 4 /mm² y 81 ± 30 μm). El suelo poco apto fue el que registró la mejor combinación de valores de fibras y vasos (mayor longitud de fibras y espesor de pared, con bajo número de vasos de diámetro intermedio). Los árboles muestreados a mayor edad produjeron madera con mayor longitud de fibras, espesor de pared y diámetro de vasos. Tomando la densidad como índice de calidad tecnológica para diferentes industrias (aserrado-papel), la madera producida puede considerarse un material relativamente homogéneo (0,547 ± 0,05 g/cm3).The aim of the work was to analyze the variability established by provenances, soil and harvest ages in the anatomy and density of Eucalyptus globulus Labil. commercially implanted in the southeast of the province of Buenos Aires, Argentina. We selected 23 trees from 3 provenances (Valdivia, Angol and Portuguesa), 4 soil categories (from very suitable to unsuitable) and 2 ranges of harvest ages (10-11 and 14-15 years). The trees of the Portuguese provenance recorded the highest values of height and diameter, while the soils and age had no influence. The quality of the wood produced in terms of fiber and vessel biometrics tends to be different according to these three factors, while the differences in the basic density of the wood were not important from the technological point of view in the age range of 14 -15 years. The Portuguese provenance presented the longest fibers (908 ± 230 μm) and the lowest wall thickness (2.05 ± 0.6 μm), the vessels were intermediate in number and diameter (11 ± 4 / mm2 and 81 ± 30 μm). The least suitable soil was the one that recorded the best combination of fiber and vessel values (greater fiber length and wall thickness, with fewer intermediate diameter vessels). The trees sampled at a older age produced wood with greater fiber length, wall thickness and vessel diameter. The growth of trees (height and diameter) did not correlate with the quality of wood produced. Taking density as an index of technological quality for different industries (sawing-paper), the wood produced can be considered a relatively homogeneous material (0.557 ± 0.05 g / cm³).Facultad de Ciencias Agrarias y Forestale

Variability in the anatomy and density of Eucalyptus globulus wood: preliminary analysis of the effect of provenance, soil and age

El objetivo del trabajo fue analizar la variabilidad que establecen las procedencias, suelo y edades de cosecha en la anatomía y densidad de la madera de Eucalyptus globulus Labil. implantados comercialmente en el sudeste de la Provincia de Buenos Aires, Argentina. Se seleccionaron 23 árboles de 3 procedencias (Valdivia, Angol y Portuguesa), 4 categorías de suelos (de muy apto a no apto) y 2 rangos de edades de cosecha (10-11 y 14-15 años). Los árboles de la procedencia Portuguesa registraron los mayores valores de altura y diámetro, mientras que los suelos y edad no tuvieron influencia. La calidad de la madera producida en términos de biometría de fibras y vasos, tiende a ser diferente según estos tres factores, mientras que las diferencias en densidad básica de la madera no fueron importantes desde el punto de vista tecnológico en el rango de edad de 14-15 años. La procedencia Portuguesa presentó las fibras más largas (908 ± 230 μm) y el menor espesor de pared (2,05 ± 0,6 μm), los vasos fueron intermedios en número y diámetro (11 ± 4 /mm² y 81 ± 30 μm). El suelo poco apto fue el que registró la mejor combinación de valores de fibras y vasos (mayor longitud de fibras y espesor de pared, con bajo número de vasos de diámetro intermedio). Los árboles muestreados a mayor edad produjeron madera con mayor longitud de fibras, espesor de pared y diámetro de vasos. Tomando la densidad como índice de calidad tecnológica para diferentes industrias (aserrado-papel), la madera producida puede considerarse un material relativamente homogéneo (0,547 ± 0,05 g/cm3).The aim of the work was to analyze the variability established by provenances, soil and harvest ages in the anatomy and density of Eucalyptus globulus Labil. commercially implanted in the southeast of the province of Buenos Aires, Argentina. We selected 23 trees from 3 provenances (Valdivia, Angol and Portuguesa), 4 soil categories (from very suitable to unsuitable) and 2 ranges of harvest ages (10-11 and 14-15 years). The trees of the Portuguese provenance recorded the highest values of height and diameter, while the soils and age had no influence. The quality of the wood produced in terms of fiber and vessel biometrics tends to be different according to these three factors, while the differences in the basic density of the wood were not important from the technological point of view in the age range of 14 -15 years. The Portuguese provenance presented the longest fibers (908 ± 230 μm) and the lowest wall thickness (2.05 ± 0.6 μm), the vessels were intermediate in number and diameter (11 ± 4 / mm2 and 81 ± 30 μm). The least suitable soil was the one that recorded the best combination of fiber and vessel values (greater fiber length and wall thickness, with fewer intermediate diameter vessels). The trees sampled at a older age produced wood with greater fiber length, wall thickness and vessel diameter. The growth of trees (height and diameter) did not correlate with the quality of wood produced. Taking density as an index of technological quality for different industries (sawing-paper), the wood produced can be considered a relatively homogeneous material (0.557 ± 0.05 g / cm³)

Variability in the anatomy and density of Eucalyptus globulus wood: preliminary analysis of the effect of provenance, soil and age

El objetivo del trabajo fue analizar la variabilidad que establecen las procedencias, suelo y edades de cosecha en la anatomía y densidad de la madera de Eucalyptus globulus Labil. implantados comercialmente en el sudeste de la Provincia de Buenos Aires, Argentina. Se seleccionaron 23 árboles de 3 procedencias (Valdivia, Angol y Portuguesa), 4 categorías de suelos (de muy apto a no apto) y 2 rangos de edades de cosecha (10-11 y 14-15 años). Los árboles de la procedencia Portuguesa registraron los mayores valores de altura y diámetro, mientras que los suelos y edad no tuvieron influencia. La calidad de la madera producida en términos de biometría de fibras y vasos, tiende a ser diferente según estos tres factores, mientras que las diferencias en densidad básica de la madera no fueron importantes desde el punto de vista tecnológico en el rango de edad de 14-15 años. La procedencia Portuguesa presentó las fibras más largas (908 ± 230 μm) y el menor espesor de pared (2,05 ± 0,6 μm), los vasos fueron intermedios en número y diámetro (11 ± 4 /mm² y 81 ± 30 μm). El suelo poco apto fue el que registró la mejor combinación de valores de fibras y vasos (mayor longitud de fibras y espesor de pared, con bajo número de vasos de diámetro intermedio). Los árboles muestreados a mayor edad produjeron madera con mayor longitud de fibras, espesor de pared y diámetro de vasos. Tomando la densidad como índice de calidad tecnológica para diferentes industrias (aserrado-papel), la madera producida puede considerarse un material relativamente homogéneo (0,547 ± 0,05 g/cm3).The aim of the work was to analyze the variability established by provenances, soil and harvest ages in the anatomy and density of Eucalyptus globulus Labil. commercially implanted in the southeast of the province of Buenos Aires, Argentina. We selected 23 trees from 3 provenances (Valdivia, Angol and Portuguesa), 4 soil categories (from very suitable to unsuitable) and 2 ranges of harvest ages (10-11 and 14-15 years). The trees of the Portuguese provenance recorded the highest values of height and diameter, while the soils and age had no influence. The quality of the wood produced in terms of fiber and vessel biometrics tends to be different according to these three factors, while the differences in the basic density of the wood were not important from the technological point of view in the age range of 14 -15 years. The Portuguese provenance presented the longest fibers (908 ± 230 μm) and the lowest wall thickness (2.05 ± 0.6 μm), the vessels were intermediate in number and diameter (11 ± 4 / mm2 and 81 ± 30 μm). The least suitable soil was the one that recorded the best combination of fiber and vessel values (greater fiber length and wall thickness, with fewer intermediate diameter vessels). The trees sampled at a older age produced wood with greater fiber length, wall thickness and vessel diameter. The growth of trees (height and diameter) did not correlate with the quality of wood produced. Taking density as an index of technological quality for different industries (sawing-paper), the wood produced can be considered a relatively homogeneous material (0.557 ± 0.05 g / cm³).Facultad de Ciencias Agrarias y Forestale

Variability in the anatomy and density of Eucalyptus globulus wood: preliminary analysis of the effect of provenance, soil and age

El objetivo del trabajo fue analizar la variabilidad que establecen las procedencias, suelo y edades de cosecha en la anatomía y densidad de la madera de Eucalyptus globulus Labil. implantados comercialmente en el sudeste de la Provincia de Buenos Aires, Argentina. Se seleccionaron 23 árboles de 3 procedencias (Valdivia, Angol y Portuguesa), 4 categorías de suelos (de muy apto a no apto) y 2 rangos de edades de cosecha (10-11 y 14-15 años). Los árboles de la procedencia Portuguesa registraron los mayores valores de altura y diámetro, mientras que los suelos y edad no tuvieron influencia. La calidad de la madera producida en términos de biometría de fibras y vasos, tiende a ser diferente según estos tres factores, mientras que las diferencias en densidad básica de la madera no fueron importantes desde el punto de vista tecnológico en el rango de edad de 14-15 años. La procedencia Portuguesa presentó las fibras más largas (908 ± 230 μm) y el menor espesor de pared (2,05 ± 0,6 μm), los vasos fueron intermedios en número y diámetro (11 ± 4 /mm² y 81 ± 30 μm). El suelo poco apto fue el que registró la mejor combinación de valores de fibras y vasos (mayor longitud de fibras y espesor de pared, con bajo número de vasos de diámetro intermedio). Los árboles muestreados a mayor edad produjeron madera con mayor longitud de fibras, espesor de pared y diámetro de vasos. Tomando la densidad como índice de calidad tecnológica para diferentes industrias (aserrado-papel), la madera producida puede considerarse un material relativamente homogéneo (0,547 ± 0,05 g/cm3).The aim of the work was to analyze the variability established by provenances, soil and harvest ages in the anatomy and density of Eucalyptus globulus Labil. commercially implanted in the southeast of the province of Buenos Aires, Argentina. We selected 23 trees from 3 provenances (Valdivia, Angol and Portuguesa), 4 soil categories (from very suitable to unsuitable) and 2 ranges of harvest ages (10-11 and 14-15 years). The trees of the Portuguese provenance recorded the highest values of height and diameter, while the soils and age had no influence. The quality of the wood produced in terms of fiber and vessel biometrics tends to be different according to these three factors, while the differences in the basic density of the wood were not important from the technological point of view in the age range of 14 -15 years. The Portuguese provenance presented the longest fibers (908 ± 230 μm) and the lowest wall thickness (2.05 ± 0.6 μm), the vessels were intermediate in number and diameter (11 ± 4 / mm2 and 81 ± 30 μm). The least suitable soil was the one that recorded the best combination of fiber and vessel values (greater fiber length and wall thickness, with fewer intermediate diameter vessels). The trees sampled at a older age produced wood with greater fiber length, wall thickness and vessel diameter. The growth of trees (height and diameter) did not correlate with the quality of wood produced. Taking density as an index of technological quality for different industries (sawing-paper), the wood produced can be considered a relatively homogeneous material (0.557 ± 0.05 g / cm³).Facultad de Ciencias Agrarias y Forestale

Electrical Properties and Electromagnetic Interference Shielding Effectiveness of Interlayered Systems Composed by Carbon Nanotube Filled Carbon Nanofiber Mats and Polymer Composites

The demand for multifunctional requirements in aerospace, military, automobile, sports, and energy applications has encouraged the investigation of new composite materials. This study focuses on the development of multiwall carbon nanotube (MWCNT) filled polypropylene composites and carbon nanofiber composite mats. The developed systems were then used to prepare interlayered composites that exhibited improved electrical conductivity and electromagnetic interference (EMI) shielding efficiency. MWCNT-carbon nanofiber composite mats were developed by centrifugally spinning mixtures of MWCNT suspended in aqueous poly(vinyl alcohol) solutions. The developed nanofibers were then dehydrated under sulfuric acid vapors and then heat treated. Interlayered samples were fabricated using a nanoreinforced polypropylene composite as a matrix and then filled with carbon fiber composite mats. The in-plane and through-plane electrical conductivity of an eight-layered flexible carbon composite (0.65 mm thick) were shown to be 6.1 and 3.0 × 10−2 S·cm−1, respectively. The EMI shielding effectiveness at 900 MHz increased from 17 dB for the one-layered composite to 52 dB for the eight-layered composite. It was found that the reflection of the electromagnetic waves was the dominating mechanism for EMI shielding in the developed materials. This study opens up new opportunities for the fabrication of novel lightweight materials that are to be used in communication systems

Wood density and anatomy of three Eucalyptus species: implications for hydraulic conductivity

Aim of the study: To characterize wood anatomical traits of three Eucalyptus species that differ in wood density and ecological requirements, and to examine the relationships between some anatomical features, wood density, and theoretical xylem hydraulic conductivity (Ks). Area of study: We analyzed 86 trees from three sites of Argentina (Entre Ríos and Buenos Aires Provinces). Methods: The sampled trees were Eucalyptus globulus, E. grandis and E. viminalis ranging from 11 to 15 years old. One stem disc was cut from each tree to determine wood density and identify quantitative anatomical features of vessels and fibers. Vessel composition (S, size - to-number ratio, a measure of vessel size distribution) and lumen fraction (F, the total sapwood area available for water transport) were estimated. Results: E. grandis, the species with the highest growth rates, presented the highest theoretical Ks. This was associated with anatomical features such as a high density of wide vessels resulting in high F. On the other hand, E. viminalis, the species with the lowest growth rates and highest resistance to environmental stress, showed lower Ks as a result of a low density of wide vessels. These two species differed not only greatly in wood density but also in fiber characteristics. In the case of E. globulus, vessels were relatively narrow, which resulted in the lowest theoretical Ks, fibers were small, and wood density intermediate. Research highlights: F had greater influence on Ks than S. The anatomical characteristics and wood density could only partly explain the differential growth or resistance to stress of the studied species.Facultad de Ciencias Agrarias y Forestale

WISE/NEOWISE observations of Active Bodies in the Main Belt

We report results based on mid-infrared photometry of 5 active main belt objects (AMBOs) detected by the Wide-field Infrared Survey Explorer (WISE) spacecraft. Four of these bodies, P/2010 R2 (La Sagra), 133P/Elst-Pizarro, (596) Scheila, and 176P/LINEAR, showed no signs of activity at the time of the observations, allowing the WISE detections to place firm constraints on their diameters and albedos. Geometric albedos were in the range of a few percent, and on the order of other measured comet nuclei. P/2010 A2 was observed on April 2-3, 2010, three months after its peak activity. Photometry of the coma at 12 and 22 {\mu}m combined with ground-based visible-wavelength measurements provides constraints on the dust particle mass distribution (PMD), dlogn/dlogm, yielding power-law slope values of {\alpha} = -0.5 +/- 0.1. This PMD is considerably more shallow than that found for other comets, in particular inbound particle fluence during the Stardust encounter of comet 81P/Wild 2. It is similar to the PMD seen for 9P/Tempel 1 in the immediate aftermath of the Deep Impact experiment. Upper limits for CO2 & CO production are also provided for each AMBO and compared with revised production numbers for WISE observations of 103P/Hartley 2.Comment: 32 Pages, including 5 Figure

Wood density and anatomy of three Eucalyptus species: implications for hydraulic conductivity

Aim of the study: To characterize wood anatomical traits of three Eucalyptus species that differ in wood density and ecological requirements, and to examine the relationships between some anatomical features, wood density, and theoretical xylem hydraulic conductivity (Ks). Area of study: We analyzed 86 trees from three sites of Argentina (Entre Ríos and Buenos Aires Provinces). Methods: The sampled trees were Eucalyptus globulus, E. grandis and E. viminalis ranging from 11 to 15 years old. One stem disc was cut from each tree to determine wood density and identify quantitative anatomical features of vessels and fibers. Vessel composition (S, size - to-number ratio, a measure of vessel size distribution) and lumen fraction (F, the total sapwood area available for water transport) were estimated. Results: E. grandis, the species with the highest growth rates, presented the highest theoretical Ks. This was associated with anatomical features such as a high density of wide vessels resulting in high F. On the other hand, E. viminalis, the species with the lowest growth rates and highest resistance to environmental stress, showed lower Ks as a result of a low density of wide vessels. These two species differed not only greatly in wood density but also in fiber characteristics. In the case of E. globulus, vessels were relatively narrow, which resulted in the lowest theoretical Ks, fibers were small, and wood density intermediate. Research highlights: F had greater influence on Ks than S. The anatomical characteristics and wood density could only partly explain the differential growth or resistance to stress of the studied species.Facultad de Ciencias Agrarias y Forestale

Role of whole brain radiotherapy in the management of infratentorial metastases from lung and breast cancer

BACKGROUND: Brain metastases (BM) occur in almost one third of patients with systemic malignancies. Only a small number of studies focus on infratentorial location and whole brain radiotherapy (WBRT) as the main non-surgical management. The aim of the study was to compare the prognosis of patients treated with WBRT among patients with supra- or infratentorial lesions. MATERIALS AND METHODS: At a single center, 263 patients with either breast (BC) or lung (LC) cancer, that had developed BM and received treatment with WBRT, were analyzed during an 8-year period. RESULTS: A total of 152 patients with BC and 111 with LC were analyzed, median age at the time of BM was 50.7 years, systemic activity other than BM was detected in 91%. Newly diagnosed BM were supratentorial in 40%, infratentorial in 10% and 51% in both locations. Median overall survival was 13 months (95% CI: 11.1–14.8 months), without significant difference between supra- or infratentorial location. WBRT alone was administered in 79% of patients, whereas WBRT with chemtoreapy was provided for 21%. CONCLUSION: In patients with BM from LC or BC that were not candidates for surgical resection, palliative WBRT appears to be equally effective in those with supra- or infratentorial locations