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X-ray based microdensitometry is conventionally used to produce climate-related tree-ring records. Micro X-ray fluorescence (µXRF) applications represent another growing area of interest and opportunities in dendrochronology. This paper demonstrates a method to correctly juxtapose and precisely synchronise the densitometry and µXRF profiles. Among µXRF variables, full fluorescence spectrum (FFS) corresponds distinctly well with the microdensitometry-based wood density variations. Accordingly, the FFS provides the most applicable variable to integrate the µXRF and density profiles. The method proposed here can be used to demonstrate the strength and sign of µXRF variables and wood density relations. Moreover, the µXRF based records can be readily compared to density variables, such as the latewood maximum density, which is demonstrated in this paper. [ABSTRACT FROM AUTHOR]

One of the important properties of industrial radiographic films that determine the clarity of the resulting image is granularity. In the technical specifications for any industrial radiographic film, the manufacturer is obliged to provide information on granularity in addition to other characteristics such as sensitivity to radiation and contrast, and the companies that attest radiographic films must evaluate it. This is required by the international standard ISO 11699-1: 2008. The granularity value (among other characteristics) determines the belonging of the radiographic film to a certain class, and, consequently, the possibility of using the film in X-ray or gamma tetsing of certain objects. To assess the granularity, specific equipment and adherence to the technology of this process, regulated by ISO 11699-1: 2008, is required. The article provides information on the assessment of granularity by means of the developed stand with dummies of the optical system and the data collection system in automatic and manual modes. The developed stand was used to assess the granularity of the D5 (Agfa) radiographic film. The obtained experimental data coincide within the permissible range with the data specified in the certificate of conformity to international standards. [ABSTRACT FROM AUTHOR]

X‐ray microdensitometry on annually resolved tree‐ring samples has gained an exceptional position in last‐millennium paleoclimatology through the maximum latewood density (MXD) parameter, but also increasingly through other density parameters. For 50 years, X‐ray based measurement techniques have been the de facto standard. However, studies report offsets in the mean levels for MXD measurements derived from different laboratories, indicating challenges of accuracy and precision. Moreover, reflected visible light‐based techniques are becoming increasingly popular, and wood anatomical techniques are emerging as a potentially powerful pathway to extract density information at the highest resolution. Here we review the current understanding and merits of wood density for tree‐ring research, associated microdensitometric techniques, and analytical measurement challenges. The review is further complemented with a careful comparison of new measurements derived at 17 laboratories, using several different techniques. The new experiment allowed us to corroborate and refresh "long‐standing wisdom" but also provide new insights. Key outcomes include (i) a demonstration of the need for mass/volume‐based recalibration to accurately estimate average ring density; (ii) a substantiation of systematic differences in MXD measurements that cautions for great care when combining density data sets for climate reconstructions; and (iii) insights into the relevance of analytical measurement resolution in signals derived from tree‐ring density data. Finally, we provide recommendations expected to facilitate futureinter‐comparability and interpretations for global change research. Plain Language Summary: Paleoclimatology, the study of how the climate has changed throughout earth history, is an important component of climate change research. The wood density of tree rings is a widely used parameter to study past temperature changes. Despite wood density being widely used and considered excellent for this type of research, deriving comparable measurements at different laboratories and using a variety of techniques are proving challenging. This review compiles the current understanding and merits of wood density as a proxy in paleoclimate research. We further describe and review prevalent measurement techniques and associated analytical measurement challenges. The review is also complemented with a careful comparison of a set of new measurements derived at 17 laboratories, using several different techniques. We find that there are substantial differences in measurements performed among laboratories. The main challenge is associated with the analytical resolution when measuring small features such as the density of the latewood. We provide recommendations for future work to overcome systematic differences and towards the prospect of combining measurements from different techniques in integrative studies. Key Points: We review the merits and state of the art of tree‐ring wood microdensitometry and its associated analytical challengesWe show that systematic level offsets in mean wood density from different techniques and laboratories require correctionMeasurement resolution—notoriously difficult to control—is identified as the major challenge for future research applications [ABSTRACT FROM AUTHOR]

Reports on the soft x-ray (SXR) emission on the atomic number Z and the laser intensity. Diagram of the experimental setup; Data on the microdensitometer traces of raw spectra from various atomic number laser plasmas from C to Au; Information on the dependence of SXR emission on laser intensity; Use of pinhole transmission grating spectrometer in x-ray laser experiments.

The purpose of this study was to clarify the effects of steroid administration on the osseointegration of pure titanium implants. Twelve female New Zealand white rabbits, 8 weeks of age, were divided into two groups: a prednisolone-treated group (Group P) and a control group (Group C). In each rabbit, two implants were placed into the mandible and two into the tibial metaphyses with bone tapping. The six steroid-treated rabbits received three courses of 4 days of prednisolone injections (10 mg/kg per day) before implant placement, 1 month and 2 months after implant placement. The six control rabbits received no administration of prednisolone. Three months after implant placement, all rabbits were sacrificed. Bone density of the femur and removal torque of the implants placed in the tibia were significantly lower in Group P than in Group C. In addition, there were significant correlations between the bone density of the femur and the removal torque of the implants placed in the tibia. There was no significant difference in removal torque of the implants placed in the mandible between Group P and Group C, and there was no significant correlation between the bone density of the femur and the removal torque of the implants placed in the mandible. These results suggest that steroid administration could have less effect on the osseointegration of titanium implants in the mandible than in the skeletal bone. [ABSTRACT FROM AUTHOR]

Context Although P. nigra Arnold is one of the most important conifers in Europe, little is known about the wood’s characteristics in the southwest European region. Aims Our aims are to outline a first approach to study the growth and wood quality in P. nigra in Portugal comparing to other European natural stands and other resinous species. Methods Inter- and intra-wood density variation of P. nigra from six Portuguese sites was studied using microdensitometry. Analysis of variance (ANOVA) was performed in three subsets: 50 common rings, core (juvenile wood) and peripheral analysis (mature wood). Results The average ring density was 0.588 g cm−3 , with maximum values in the north and low altitudes. Regarding growth traits, no latitudinal and altitudinal tendencies were detected. Compared to the main timber species in Portugal (P. pinaster Aiton), P. nigra showed similar radial growth, higher density but lower intra-ring density homogeneity. The Sites effect mainly influenced latewood density components, while the Trees/Sites effect primarily influenced earlywood components. The Rings effect was found to be relatively low, with a density decrease in the tree’s first years followed by an increase in the periphery. Growth traits showed a reduction from pith to bark. Conclusion Considering the quality (density) and growth features of the Black pine, this species could be useful for the reforestation of mountainous Southern Europe areas that are not favourable for other species. [ABSTRACT FROM AUTHOR]

The Brazilian plantation forestry is well known for high yields. Such yields are not necessarily linked with acceptable wood quality. Pine plantations are an important source of timber in Brazil, and although pulp and paper production plays a dominant role, there is an increasing need for sawtimber, and even high-quality timber is in demand. The impacts of crown thinning on ring width, ring density and juvenile–mature wood of loblolly pine trees were analysed. The experimental design included no thinning, an extreme release from competition, and two practice-oriented variants with moderate and heavy thinnings. X-ray microdensitometry provided ring width and density for 1197 rings and 44 trees. Mean ring width at 1.3 m height varied from 6 to 9 mm, reaching a maximum of 22 mm during the first 3–6 years regardless of thinning intensity. Only occasional differences were verified in ring densities produced from the different thinning variants. The transition from juvenile to mature wood occurred between 13 and 17 years of age. From the analysis of wood density, extreme and early thinning delayed the production of mature wood in ~ 4 years compared with non-thinned or practice-oriented thinned stands. At the same harvest age, thinning had no effect on wood density. However, harvest age itself was a determinant for obtaining wood of higher density. Altogether, results indicated that regarding current market demands no constraints related to the analysed wood characteristics are to be expected, even if extreme thinning regimes are applied. [ABSTRACT FROM AUTHOR]

Wood density is one of the most important and well documented wood quality attributes. However, studies focusing on the effects of thinning combined with pruning on wood density in Mediterranean areas are scarce, even though both are recommended practices in forests managed for the production of high-quality timber. We assess the effects of both silvicultural interventions on wood density traits (tree-ring, earlywood, and latewood) and on the percentage of latewood, on an annual scale, for the main timber species Pinus sylvestris L. and Pinus nigra Arnold (subsp. nigra and subsp. salzmannii) in Mediterranean mountains. To this end, three trials (one species per trial) were established in monospecific reforestations in the 1990s. Three silvicultural treatments were applied: thinning, thinning combined with pruning, and a control. At the time of installation, stand ages ranged from 26 to 37 years. Small differences were found among treatments in regard to the wood density attributes, with no significant effects of thinning and pruning on the studied wood traits in either timber species. The two subspecies of P. nigra presented comparatively denser wood than P. sylvestris. Our results suggest that thinning and pruning treatments can be applied without causing unfavourable changes to wood density. [ABSTRACT FROM AUTHOR]

Euxylophora paraensis Huber - Rutaceae, popularly known as yellow heart, is a species with a low-density population that has suffered intense exploitation in recent decades. This has led to its inclusion in the IBAMA list of endangered species. This study aimed to evaluate the existence of growth rings and their annuity in five trees of Euxylophora paraensis through the x-ray microdensitometry technique, as well as to compare them using the classical method. Application feasibility of this technique can be deepened through future, broader dendroecological studies, which may better elucidate the understanding of the species population dynamics and promote more sustainable uses. Wood disks were collected from the base of five 29-year-old trees from a planting site in the Curua-Una Experimental Station, located in Prainha, Pará State, Brazil. Samples were polished and sanded for the x-ray microdensitometric analysis. Values of minimum, average, and maximum density (0.581, 0.84, and 1.077gcm-3, respectively) were obtained. There was a significant difference in density between the studied trees. Growth rings boundaries, through densitometric pith-bark profile are demarcated by fibrous zones, with density variation between the early wood and late wood. This study concludes that the growth rings of the studied species are distinct and annual, validating the technique used. [ABSTRACT FROM AUTHOR]

Previous research using microdensitometric scanning and computer graphic image analysis showed that T-banded segments of human metaphase chromosomes usually exhibit an asymmetrical distribution of high density (HD) chromatin between sister chromatids. Here, we employed the same methods to analyze HD chromatin distribution at opposite ends of T-banded human lymphocyte chromosomes. This study revealed that in most chromosomes with an asymmetrical distribution of HD chromatin at both ends, the highest densities of each arm were located in opposite chromatids. The frequency of this configuration was 0.792 per chromosome, indicating that the highest chromatin densities of the terminal segments of T-banded human chromosomes were non-randomly distributed at opposite chromosome arms. The possible relationship of this observation to the mode of replication of the terminal chromosome region is briefly discussed.

Comparative analyses of interspecific data in evolutionary biology usually require specific methods to remove the effects of phylogenetic inertia. When phylogenetic inertia is not considered, the Canarian Pimelia species show a positive, and almost significant (Prob. = 0.066) correlation between nuclear genome size and body size. However, after controlling for phylogenetic inertia there was a negative and significant correlation (Prob. = 0.007 to 0.017, depending on the DNA fraction considered). Such a change in the relationship after controlling for phylogenetic inertia is rarely reported. Moreover, the relationship usually reported is positive and thought be a consequence of species having a similar number of cells at the same stage of development. The aim of the present study is to report a case of a negative correlation, but not to explain the causal mechanism involved in genome size variations or propose a formal hypothesis on the specific links between DNA content and body size. However, a common explanation of the change in the relationship, i.e., positive to negative, is suggested. Moreover, the data available on the highly repetitive, non-coding satellite DNA allows us to analyse the specific pattern exhibited by this fraction.

Ionizing irradiation is a well-established therapeutic modality for malignant gliomas. Due to its high cellular uptake, 5-aminolevulinic acid (ALA) is used for fluorescence-guided resection of malignant gliomas. We have previously shown that 5-ALA sensitizes glioma cells to irradiation in vitro. The aim of the present study was to assess whether 5-ALA acts as a radiosensitizer in experimental glioma in vivo. Rats were subcutaneously injected with 9L gliosarcoma cells and administered 5-ALA. The accumulation of 5-ALA-induced protoporphyrin IX was confirmed by high-performance liquid chromatography (HPLC) analysis. Subcutaneous (s.c.) tumors were subsequently irradiated with 2 Gy/day for five consecutive days. In the experimental glioma model, high-performance liquid chromatography analysis revealed a high level of accumulation of 5-ALA-induced protoporphyrin IX in s.c. tumors 3 h after 5-ALA administration. Multi-dose ionizing irradiation induced greater inhibition of tumor growth in rats that were administered 5-ALA than in the non-5-ALA-treated animals. Immunohistochemical analysis of the s.c. tumors revealed that numerous ionized calcium-binding adapter molecule 1 (Iba1)-positive macrophages gathered at the surface of and within the s.c. tumors following multi-dose ionizing irradiation in combination with 5-ALA administration. By contrast, the s.c. tumors in the control group scarcely showed aggregation of Iba1-positive macrophages. These results suggested that multi-dose ionizing irradiation with 5-ALA induced not only a direct cytotoxic effect but also enhanced the host antitumor immune response and thus caused high inhibition of tumor growth in experimental glioma. [ABSTRACT FROM AUTHOR]

X-ray based tree-ring data of maximum latewood densities (MXD) was combined for south-eastern Finland. This data originated from subfossil and modern pine ( Pinus sylvestris L.) materials comprising a continuous dendroclimatic record over the past millennium. Calibrating and verifying the MXD chronologies against the instrumental temperature data showed a promising opportunity to reconstruct warm-season (May through September) temperature variability. A new palaeotemperature record correlated statistically significantly with the long instrumental temperature records in the region and adjacent areas since the 1740s. Comparisons with tree-ring based (MXD and tree-ring width) reconstructions from northern Fennoscandia and northern Finland exhibited consistent summer temperature variations through the Medieval Climate Anomaly, Little Ice Age, and the 20 century warmth. A culmination of the LIA cooling during the early 18 century appeared consistently with the Maunder Minimum, when the solar activity was drastically reduced. A number of coolest reconstructed events between AD 1407 and 1902 were coeval to years of crop failure and famine as documented in the agro-historical chronicles. Results indicate an encouraging possibility of warm-season temperature reconstructions using middle/south boreal tree-ring archives to detail and enhance the understanding of past interactions between humans, ecosystems and the earth. [ABSTRACT FROM AUTHOR]

The wood quality of maritime pine ( Pinus pinaster Ait.) is discussed in view of spatial variability of density, annual growth ring characteristics, and transverse elastic properties within and among five basal logs. X-ray microdensitometry measurements are carried out to assess both average ( Dmean) and local ( DEW, DLW) densities of annual growth rings, as well as the respective dimensions (EWW, LWW) and fractions of earlywood (EW) and latewood (LW) layers. Mechanical tensile tests on a set of specimens with different ring orientation are proposed. Transverse elastic properties are determined by coupling an inverse identification strategy with full-field deformation measurements provided by digital image correlation. For a suitable range of off-axis angles, this method allows the simultaneous characterisation of the four orthotropic elastic properties in the RT plane: ER, ET, νRT, and GRT. These results are found in agreement with reference values. From the sampled specimens among logs, ER and GRT are robustly identified in all cases and therefore are selected for further analysis of structure-properties relationships. Correlations between Dmean and ER and GRT are positive and statistically significant. Furthermore, other parameters also show significant correlations with the elastic constants, especially Dmin, LWW, and DEW. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The radial variation in wood density in Acacia melanoxylon R. Br. was studied using microdensitometry by sampling 20 trees with a 40-cm diameter class at four sites in Portugal. The measurements were taken from pith to bark at breast height. A. melanoxylon had an average ring density of 0.607 g cm, ranging from 0.556 to 0.630 g cm. The mean growth was 6.0 mm year. Latewood corresponded, on average, to 34 % of the ring width. Between-tree variability at each site was the main source of variation in the density components, representing between 30 and 54 % of the total variation. Between-sites variability represented from 0 to 21 % of the total variation in density components. The environmental effects (site related) were more pronounced on latewood, while the genetic effect (tree related) was more evident in earlywood. Ring width, latewood percentage and heterogeneity index were independent from site, trees in site and age effects. The values of wood density and radial growth revealed that A. melanoxylon can be important as a commercial timber species in Portugal. [ABSTRACT FROM AUTHOR]

Eucalyptus plantations have been considered for bioenergy production and hence their biological characteristics that make them amenable to intensive short-rotation forestry. Wood density is an important parameter that directly affects fuel production. This study focuses on the early assessment of density features for 19 Eucalyptus species using X-ray microdensitometry in a perspective of potential biomass production. Average ring density, earlywood density, latewood density, latewood percentage and the heterogeneity index were studied. E. polyanthemos registered the highest mean wood density value (0.84 g cm), and E. viminalis showed the lowest value (0.53 g cm). An indicator for the potential wood biomass (PWB) was calculated, with E. maculata displaying the highest biomass production index (13.4 kg). Comparison of radial growth of these species showed appreciable differences. The PWB indicator points to the prospective good aptitude for short-rotation cycle for biomass production of E. maculata, E. botryoides, E. globulus, E. nitens and E. sideroxylon. [ABSTRACT FROM AUTHOR]

Studying structure and chemistry of wood and wood-based materials is the backbone of all wood research and many techniques are at hand to do so. A very valuable modality is X-ray computed tomography (CT), able to non-destructively probe the three-dimensional (3D) structure and composition. In this paper, we elaborate on the use of Nanowood, a flexible multi-resolution X-ray CT set-up developed at UGCT, the Ghent University Centre for X-ray Tomography. The technique has been used successfully in many different fields of wood science. It is illustrated how 3D structural and microdensitometrical data can be obtained using different scan set-ups and protocols. Its potential for the analysis of modified wood is exemplified, e.g. for the assessment of wood treated with hydrophobing agents, localisation of modification agents, pathway analysis related to functional tissues, dimensional changes due to thermal treatment, etc. Furthermore, monitoring of transient processes is a promising field of activity too. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hyperspectral imaging allows measuring wood density at 79μm spatial resolution. [•] Partial least squares or neural networks transform hyperspectral data to density. [•] Neural networks provide better results than partial least squares. [•] The mean absolute percentage error for neural networks is 6.49%. [•] Our method may substitute X-ray microdensitometry measurements. [Copyright &y& Elsevier]

This paper reports a novel application of hyperspectral imaging (a spectroscopic technique) for measuring wood density profiles at the growth ring scale. The measurements were performed with a spatial resolution of 79 µm. In the present case, hyperspectral imaging was used to measure wood sample reflectance for light in the wavelength range between 380 and 1028 nm, with a resolution of approximately 0.6 nm. The work was performed with 34 samples collected from 34 trees of Pinus pinea. A total of 34,093 density points were used to create and validate a partial least-squares (PLS) regression that converts spectroscopic reflectance data into density values. The coefficient of determination value between the present method and X-ray microdensitometry is 0.810 with a root mean squared error of 6.54×10-2 g.cm-3. [ABSTRACT FROM AUTHOR]

Prall F, Maletzki C & Linnebacher M (2012) Histopathology 61, 823-832 Microdensitometry of osteopontin as an immunohistochemical prognostic biomarker in colorectal carcinoma tissue microarrays: potential and limitations of the method in 'biomarker pathology' Aims: To explore the potential and limitations of 'biomarker pathology' with quantitative immunohistochemistry on tissue microarrays, taking osteopontin and colorectal carcinoma as a model system. Methods and results: Microdensitometry for quantitative evaluation of osteopontin immunohistochemistry (clone OP3N) on digital microphotographs using the public domain software ImageJ was observed to be straightforward to perform and reliable. However, using colorectal carcinoma cell lines ( n = 11) the correlation between densitometric evaluations of Western blots and microdensitometry of immunocytochemistry of slide cultures was only moderate. A virtual resampling method to simulate tissue microarrays showed that, due to heterogeneity of immunostaining, tumours were misclassified in nearly 20% of the arrays, even if four punches were used. With regard to prognosis, microdensitometric evaluation of a tissue microarray made of a clinicopathologically well-characterized series of colorectal carcinomas with long-term follow-up (222 cases evaluable in the tissue microarray, UICC Stages I-III/R0) showed a moderate survival advantage of patients with high osteopontin expression by microdensitometry. Conclusions: These results challenge the basic assumption that microdensitometry is a precise technique for the quantification of proteins detected by immunohistochemistry and delineate drawbacks encountered when working with tissue microarrays in clinicopathological studies. [ABSTRACT FROM AUTHOR]

Italy is one of the major users of cherry wood (Prunus avium L.), and its cultivation has been increasing since the early nineties, together with studies aimed at improving genotypes, with a selection usually based on growth, stem form, vigor, and tree adaptation. Here, the phenotypic correlations between growth rate and the physical and mechanical properties of wood are investigated in two wild cherry plantations. X-ray microdensitometry was also applied to analyze the age-age correlations of wood density. It was shown that growth rate did not affect wood properties, and density was confirmed to be the trait that best represents the main properties of wood. The absence of relationships between wood density and growth rate was confirmed by densitometric analysis, although an increase of wood density with an increase of ring width was detected for very narrow rings (less than 3 mm wide). The average density at age 7 to 8 was observed to be highly correlated (r > 0.90) to the average density of a 19-year-old tree, allowing reliable estimation of the wood properties of older trees by early investigation of young trees. [ABSTRACT FROM AUTHOR]

Abstract: We analyzed how the pretreatment method of Scots pine (Pinus sylvestris L.) wood specimens together with X-ray methodology applied for density analyses affect resulting tree-ring data and derived proxy-based climate information. We also evaluated whether these results from two contrasting laboratory circumstances could be homogenized by applying dendroclimatic statistical methods. For this study, we measured a pair of X-ray based microdensitometry datasets using double samples of subfossil and recent wood specimens. Dendrochronological information of earlywood and latewood series was examined to determine for alterations in the resulting data. We found that the level of overall density, its trend over cambial ages and the growth amplitude altered due to the sample pretreatment/density measuring exercise, which means that comparisons of heterogeneous datasets should be, in general, regarded cautiously. Dendrochronological standardization did, however, even out several potentially biasing influences from the differing overall densities and their trends. The two latewood (maximum) density chronologies yielded paleoclimatic reconstructions which both calibrated and verified satisfactorily with the instrumental warm-season (March–September) mean temperatures. The transfer functions were found to further equalize the differences between the two proxy records. We recommend (if no strictly homogenous data are available) reconciling similar data assemblages through transfer functions with multiple independent variables. [Copyright &y& Elsevier]

• Context: Teak ( Tectona grandis L.f.) is a tropical timber which is appreciated worldwide and has been planted into many regions of the tropics. It is essential to obtain information about provenance variation of basic wood properties in order to preserve the wood quality of end-products derived from future plantations. Figuring is one of the wood characteristics valued for panelling and furniture and it is an important parameter to evaluate the quality of teak wood. The ring structure affects within-ring and between-ring colour variation and, therefore, the figure of wood and the related aesthetical aspects. • Methods: By means of microdensity profiles, we constructed a segmented linear model that depicts the anatomical structure of the rings. It effectively distinguished ring porous and diffuse porous rings, leading to the development of an efficient ring porosity index, further used to study the provenance variation of the ring structure. • Results: A significant provenance effect was detected for both wood density variables and ring anatomical structure. Although no correlation was detected between the ring structure and the precipitation level at the provenance origin, the two provenances from very wet climates were distinguished by low values of ring porosity index (diffuse porous ring). • Conclusion: The progenies in our study, collected from origins with various climates, planted in a new climate, seem to maintain to some extent the wood characteristics typical of their mother trees, suggesting that these ring characteristics may be inherited. [ABSTRACT FROM AUTHOR]

The wood of Lam. was studied regarding its density variation within and between trees using microdensitometry techniques in 10 trees growing in northern Portugal. The observations were made in mature trees at several height levels (stem base and 1.3, 3.4, 5.5, 7.6, and 9.7 m). Variance analysis was done considering the core cylinder (first 15 rings) and the sheath (last 10 rings) in relation to tree, height level, and ring effects and their interactions. The wood revealed a high mean density of 0.848 g·cm-3 with small differences between earlywood and latewood (0.717 and 0.908 g·cm-3, respectively). Latewood corresponded on average to 66% of the total ring width, which averaged 2.4 mm. Wood density decreased with height and radially from pith to cambium. However, within-tree variation was of very moderate magnitude although higher for juvenile wood. Variation between trees was also small (6% coefficient of variation of the mean) and higher for the mature wood. Quercus faginea wood compares favourably with other oak species with regard to density characteristics and may be considered for production of quality solid wood products. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the possibility to apply high-speed rotation-induced wood-dowel welding technique to two Canadian hardwood species commonly used for furniture and structural applications, sugar maple (Acer saccharum) and yellow birch (Betula alleghaniensis). Different factors have been evaluated such as the wood species, the grain orientation, the rotation rate, as well as the receiver hole diameter. The results indicate that high-speed rotation-induced wood-dowel welding can be suitable for these two wood species with average tensile strength values comparable to their respective PVAc-glued joints. Additionally, wood-welded joints presented higher water resistance than their glued-joint counterparts. The results of the temperature measurements confirm that the softening and degradation temperatures of wood components have been reached during the welding process. The X-ray microdensitometry analyses show an increase of density for the interfacial material between the wood substrate and the dowel, the profile of which is more uniform for sugar maple than for birch. The scanning electron micrographs of the interfacial contact zone confirm the different extents of wood-to-wood welding. [ABSTRACT FROM AUTHOR]

High density panels obtained by pressing wood veneers together in plywood or laminated veneer lumber (LVL) assembly configurations, at temperatures of 225°C to 250°C, high pressure and long press times, as long as 60 min or longer, have been shown by tensile tests, X-ray microdensitometry and scanning electron microscopy to present interphases where wood has welded just by application of the press heat alone. Short press times under the same conditions of pressure and temperature yield poor welding, or no welding at all, in the veneers interphases. [ABSTRACT FROM AUTHOR]

X-ray microdensitometry was applied to a set of Scots pinewood (i.e. low extractive content). Earlywood and latewood properties were determined as minimum and maximum densities of each tree ring and the potential influence of acetone-soluble extractives (i.e. non-structural and secondary constituents of wood) was estimated using tree-ring statistics. The occurrence of extractives in different portions of wood was determined using dendrochronological methods, by comparing the densities of unextracted and extracted wood. It was not only found that unextracted samples exhibited inflated earlywood and latewood density values, but the growth trends were also altered. Extractives flattened the inter-annual growth variability, both in earlywood and latewood, and influenced the estimation of intra-annual radial growth variations. Characterizing the varying amount of extractives is of inter-disciplinary importance. The results in this study describe their occurrence and show that the radial variations in extractives could be highly detailed by simply using densitometry-based dendrochronology. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate that artificial neural network modeling is a viable tool to predict the processing dependence of gravure printed light-emitting polymer layers for flexible OLED lighting applications. The (local) thickness of gravure printed light-emitting polymer (LEP) layers was analyzed using microdensitometry, after which the data was used to train a multi-layer neural network using error back propagation. Cell engraving depth, printing speed, and polymer concentration were used as input parameters of the neural network. Mean printed layer thickness, relative RMS roughness and feature anisotropy were defined as output parameters. The inhomogeneity of the gravure printed LEP layers was defined by two parameters, being the normalized standard deviation from the mean layer thickness, as well as the anisotropy or ‘directionality’ of the roughness features. Despite the limited number of input parameters, a fair prediction accuracy was obtained once new input data was fed into the trained network. The prediction error for the three output parameters was of the order: anisotropy>roughness>mean layer thickness. Calculating the magnitude of the output parameters as a function of the total space determined by the input parameters can be used as a way to find optimal printing conditions. These ‘landscape’ plots also reveal qualitative information on the rheological behavior of the inks during the printing process. [Copyright &y& Elsevier]

Copyright of Collegium Antropologicum is the property of Croatian Anthropological Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A change in linear welding conditions, namely higher vibration frequency (150 Hz) and lower displacement (2 mm) during welding, produced a quicker rise in temperature of the weldline. This allowed a much shorter welding time (1.5 s). X-ray microdensitometry mapping showed a progressive increase in broadening and average density of the weldline as the welding time lengthens. As the welding time lengthens the maximum temperature reached at the end of welding is progressively higher. This causes increasingly greater degradation. This effect was confirmed also by CP-MAS 13C NMR and it was found that the lower is the degree of deterioration of the weldline of the wood joint the shorter is the welding time. Monitoring of the temperature of the weldline showed that the temperature reached in wood joints during welding was inversely correlated to its water resistance. Furthermore, the increase in weldline temperature is markedly quicker at a vibration frequency of 150 Hz than at 100 Hz. Thus, the shorter is the welding time the lower is the degree of deterioration of the weldline of the wood joint. This appears to be due to welding occuring when water vapour is still present in the joint, hence providing a less damaging welding environment. [ABSTRACT FROM AUTHOR]

Neuropeptide Y (NPY) is an important neuromodulator found in central and peripheral neurons. NPY was investigated in the peripheral auditory pathway of conventional housed rats and after nontraumatic sound stimulation in order to localize the molecule and also to describe its response to sound stimulus. Rats from the stimulation experiment were housed in monitored sound-proofed rooms. Stimulated animals received sound stimuli (pure tone bursts of 8 kHz, 50 ms duration presented at a rate of 2 per second) at an intensity of 80 dB sound pressure level for 1 hr per day during 7 days. After euthanizing, rat cochleae were processed for one-color immunohistochemistry. The NPY immunoreactivity was detected in inner hair cells (IHC) and also in pillar and Deiters' cells of organ of Corti, and in the spiral ganglion putative type I (≥1,009 μm3) and type II (≤225 μm3) neurons. Outer hair cells (OHC) showed light immunoreaction product. Quantitative microdensitometry showed strong and moderate immunoreactions in IHC and spiral ganglion neurons, respectively, without differences among cochlear turns. One week of acoustic stimulation was not able to induce changes in the NPY immunoreactivity intensity in the IHC of cochlea. However, stimulated rats showed an overall increase in the number of putative type I and type II NPY immunoreactive spiral ganglion neurons with strong, moderate, and weak immunolabeling. Localization and responses of NPY to acoustic stimulus suggest an involvement of the neuropeptide in the neuromodulation of afferent transmission in the rat peripheral auditory pathway. [ABSTRACT FROM AUTHOR]

The authors have investigated the dependency of radiation quality and absorbed dose on radiation field size in therapeutic carbon beams. The field size of the broad beam, formed using the passive technique, was controlled from 20 to 100 mm per side with a multileaf collimator. The absorbed dose and radiation quality on the beam center were evaluated at several depths in a water phantom using microdosimetric technique in experiments and Monte Carlo simulations. With an increase in the field size, the radiation quality was reduced, although the absorbed dose grew at the center of the field. This indicates that the dose and radiation quality at the center of the broad beam are influenced by particles from the off-center region via large-angle scattering and that such particles have relatively low radiation quality and mainly consist of fragment particles. Because such a tendency appeared to be more remarkable in the deeper region of the water phantom, it is likely that fragment particles that are born in a water phantom have a marked role in determining the field size effect. [ABSTRACT FROM AUTHOR]

Abstract  A collection of subfossil wood of Pinus sylvestris (Scots pine) was exposed to X-ray densitometry. The collection of 64 samples from the southern boreal forest zone was dendrochronologically cross-dated to a.d. 673-1788. Growth characteristics were determined by performing density profiles including the following parameters: minimum density, earlywood and latewood boundary density, maximum density, earlywood width, earlywood density, latewood width, latewood density, annual ring width and annual ring density. Seven out of the nine parameters were found to contain non-climatic growth trends and six were found to be heteroscedastic in their variance. Tree-specific records were indexed, to remove the non-climatic growth trends and stabilize the variance, and combined into nine parameter-specific tree-ring chronologies. Growth characteristics of the pines changed in parallel with the generally agreed climatic cooling from the Medieval Warm Period to the Little Ice Age: pine tree-rings showed decreasing maximum densities from the period a.d. 975-1150 to a.d. 1450–1625. A concomitant change in the intra-annual growth characteristics was detected between these periods. The findings indicate that not only the trees growing near the species’ distributional limits are sensitive to large-scale climatic variations but also the trees growing in habitats remote from the timberline have noticeably responded to past climate changes. [ABSTRACT FROM AUTHOR]

Vanilla planifolia accessions cultivated in Reunion Island display important phenotypic variation, but little genetic diversity is demonstrated by AFLP and SSR markers. This study, based on analyses of flow cytometry data, Feulgen microdensitometry data, chromosome counts, and stomatal length measurements, was performed to determine whether polyploidy could be responsible for some of the intraspecific phenotypic variation observed. Vanilla planifolia exhibited an important variation in somatic chromosome number in root cells, as well as endoreplication as revealed by flow cytometry. Nevertheless, the 2C-values of the 50 accessions studied segregated into three distinct groups averaging 5.03 pg (for most accessions), 7.67 pg (for the ‘Stérile’ phenotypes), and 10.00 pg (for the ‘Grosse Vanille’ phenotypes). For the three groups, chromosome numbers varied from 16 to 32, 16 to 38, and 22 to 54 chromosomes per cell, respectively. The stomatal length showed a significant variation from 37.75 µm to 48.25 µm. Given that 2C-values, mean chromosome numbers, and stomatal lengths were positively correlated and that ‘Stérile’ and ‘Grosse Vanille’ accessions were indistinguishable from ‘Classique’ accessions using molecular markers, the occurrence of recent autotriploid and autotetraploid types in Reunion Island is supported. This is the first report showing evidence of a recent autopolyploidy in V. planifolia contributing to the phenotypic variation observed in this species. [ABSTRACT FROM AUTHOR]

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 first 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 (0.8 84-1.068 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 significant, 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 products. [ABSTRACT FROM AUTHOR]

The nuclear DNA content (2C value) was determined in the commercial fish Galaxias maculatus (Galaxiidae) was determined by microdensitometry of erythrocyte nuclei after Feulgen staining; rainbow trout erythrocytes with a known 2C value were used as a standard. The 2C value of G. maculatus was 2.21 ± 0.12 pg and its C value was equivalent to 1.105 pg (1,082.9 Mbp). This C value is within the range recorded for other osmeriform species (0.62-3.2 pg). The average sperm head diameter of G. maculatus is lower than the average sperm head diameter of rainbow trout (used as a standard), which coincides with the differences observed in the nuclear DNA content of both species. This information increases the genome data available for G. maculatus and might be useful in future programs dealing with its genetic manipulation. [ABSTRACT FROM AUTHOR]

Abstract: This study monitored the effects of sub-lethal ischemia (post-conditioning) applied after a previous ischemic attack by way of the MnSOD immune-reactivity examined in CA1 and dentate gyrus of the rat hippocampus. The experimental 10min transient cerebral ischemia was followed by 2days of reperfusion, the rats then underwent a second ischemia (4 or 6min post-conditioning). MnSOD immune-reactivity was evaluated after 5h, 1 and 2days. Results obtained by computer microdensitometric image analysis indicated that 4min of ischemic post-conditioning caused higher MnSOD immune-reactivity than 6min. However, higher viability of CA1 neurons after stronger (6min) post-conditioning when production of MnSOD is lower, as well as differences between MnSOD in CA1 and dentate gyrus indicates another mechanism switching pro-apoptotic destination of CA1 neurons to anti-apoptotic. [Copyright &y& Elsevier]

This work proposes a novel approach to describing intraring wood density characteristics as functions of annual weather events. This approach was tested using three different maritime pine clonal experiments, in which X-ray microdensitometry has revealed conspicuous within-ring patterns affecting most of the trees in 1996. This pattern has been interpreted as the variation of tree response to weather-controlled changes of water balance during the 1996 growing season. The level of tree response was estimated using an original norm of reaction obtained from the microdensity profiles. A 1996 site drought index profile was synchronized with the 1996 microdensity profile by pairing conspicuous points of abrupt change in both profiles (breakpoints). Regression of density breakpoints on drought breakpoints describes the norm of reaction of radial increment to water availability, and the plasticity of radial increment to changes in soil moisture is described by the slope of the regression. The slope showed moderate levels of genetic control that depended on the site and could potentially be used as criteria for the evaluation of tree adaptation to weather. [ABSTRACT FROM AUTHOR]

In this paper, we extract from concurrence its variable part, denoted Λ, a function of density matrix ρ, either positive or negative. We use it to investigate entanglement dynamics of two isolated but initially entangled qubits, each coupled to its own environment. In particular, we show that it can signal whether the disentanglement of an entangled state occurs in a finite time. [ABSTRACT FROM AUTHOR]

Abstract: After Golgi–Cajal mapped neural circuits, the discovery and mapping of the central monoamine neurons opened up for a new understanding of interneuronal communication by indicating that another form of communication exists. For instance, it was found that dopamine may be released as a prolactin inhibitory factor from the median eminence, indicating an alternative mode of dopamine communication in the brain. Subsequently, the analysis of the locus coeruleus noradrenaline neurons demonstrated a novel type of lower brainstem neuron that monosynaptically and globally innervated the entire CNS. Furthermore, the ascending raphe serotonin neuron systems were found to globally innervate the forebrain with few synapses, and where deficits in serotonergic function appeared to play a major role in depression. We propose that serotonin reuptake inhibitors may produce antidepressant effects through increasing serotonergic neurotrophism in serotonin nerve cells and their targets by transactivation of receptor tyrosine kinases (RTK), involving direct or indirect receptor/RTK interactions. Early chemical neuroanatomical work on the monoamine neurons, involving primitive nervous systems and analysis of peptide neurons, indicated the existence of alternative modes of communication apart from synaptic transmission. In 1986, Agnati and Fuxe introduced the theory of two main types of intercellular communication in the brain: wiring and volume transmission (WT and VT). Synchronization of phasic activity in the monoamine cell clusters through electrotonic coupling and synaptic transmission (WT) enables optimal VT of monoamines in the target regions. Experimental work suggests an integration of WT and VT signals via receptor–receptor interactions, and a new theory of receptor–connexin interactions in electrical and mixed synapses is introduced. Consequently, a new model of brain function must be built, in which communication includes both WT and VT and receptor–receptor interactions in the integration of signals. This will lead to the unified execution of information handling and trophism for optimal brain function and survival. [Copyright &y& Elsevier]

A zig-zag pattern of rotationally welded dowels across the interface of a butt joint between two wood planks was shown to yield strong joints without any adhesive. Tests after 2 h in boiling water showed that the joints were able to resist both 2 h immersion in boiling water, as well as the subsequent oven drying. Some unusual densification patterns were observed by X-ray microdensitometry. X-ray microdensitometry analysis of densification patterns in the dowel and at the dowel/substrate interface indicate that further improvement and optimisation of this process should consider minimizing the compression rate at the end of dowel rotation as well as minimization of the insertion impact of the dowel to avoid interfacial microfissures that can sometimes develop. [ABSTRACT FROM AUTHOR]

Abstract  In this work, we present a fast and promising method to evaluate the natural durability of wood based on X-ray microdensitometry. Tested on beech and Scots pine wood samples, our findings show that this methodology and the traditional EN standards methodology based on mass loss are strongly correlated. X-ray methodology is less time consuming (we can detect the effectiveness of the attack within 5–6 weeks) and less expensive (very cheap plastic Petri dishes instead of the expensive glass Kolle flasks); moreover, the proposed method allows to thoroughly examine the phases and the kinetics of the fungal attack, and to investigate the spatial repartition of the attack within the samples due to the low thickness of the sample. [ABSTRACT FROM AUTHOR]

Background: Retinal abnormalities, particularly arteriolar narrowing, are powerful predictors of cardiovascular events. The precision of internists and ophthalmologists in the assessment of retinal vessels widths has been disputed but not evaluated against a technology of edge detection. Methods: Fifty-two patients with hypertension had optic fundi examination done by an internist and an ophthalmologist, and had retinographies taken and digitized to determine vessel diameters by a new technology of edge detection (microdensitometric method). Physicians asserted the presence of arteriolar narrowing (≤0.67) through direct ophthalmoscopy and projected retinography. The microdensitometric method measures automatically the vessel widths based on the subpixel resolution of the edge of vessel walls. Sensitivity (SE), specificity (SP), positive (PPV) and negative predictive values (NPV), and kappa statistics were calculated, taken the microdensitometric method as reference. Results: The performance of the direct examination by the internist to detect arteriolar narrowing was SE: 68.7 (67.0–70.4); SP: 72.7 (68.0–77.4); PPV: 88.0 (85.9–90.0); and NPV: 44.4 (41.5–47.4). For the ophthalmologist the figures were: SE: 74.4 (72.9–75.7); SP: 53.8 (49.8–57.8); PPV: 82.9 (81.3–84.4); and NPV: 41.2 (38.0–44.3). Kappa statistics were 0.34 (0.07–0.62) for the internist, and 0.26 (−0.03–0.53) for the ophthalmologist. Conclusions: The performance of internists and ophthalmologists to detect hypertensive microangiopathy based on low arteriolar venous ratio is low and casts doubt about the usefulness of this examination in clinical practice. [Copyright &y& Elsevier]

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