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У роботі поданий сучасний погляд на застосування різних неінвазивних методик оцінки структурно-функціонального стану кісткової тканини, зокрема рентгенівської денситометрії, у пацієнтів із недосконалим остеогенезом. На підставі застосування рентгенівської денситометрії у 22 пацієнтів із недосконалим остеогенезом встановлено порушення структурно-функціонального стану кісткової тканини та виявлено значну втрату кісткової маси; відмічено, що ступінь втрати кісткової маси залежить від типу захворювання. Автори роботи вважають, що застосування рентгенівської денситометрії в дітей та підлітків є обов’язковим та доцільним при дослідженні пацієнтів із недосконалим остеогенезом, що дає можливість об’єктивно оцінити зміни в кістковій тканині та адекватно підійти до системи ортопедичної реабілітації цієї групи пацієнтів.

Актуальність. Переломи тіл хребців є одним із тяжких ускладнень системного остеопорозу, що призводить до виникнення вираженого больового синдрому в хребті, зниження чи втрати працездатності й збільшення летальності в осіб старших вікових груп. Алгоритм FRAX та рентгенівська денситометрія є важливими методами у визначенні ризику основних остеопоротичних переломів, зокрема переломів тіл хребців. Метою нашого дослідження було визначення показників української моделі FRAX у жінок залежно від наявності вертебральних переломів. Матеріали та методи. В Українському науково-медичному центрі проблем остеопорозу були обстежені 652 жінки віком 40–89 років, які були розподілені на дві групи: перша — 523 пацієнтки без будь-яких переломів в анамнезі, друга — 129 хворих з переломами тіл хребців в анамнезі. Для оцінки показників мінеральної щільності кісткової тканини (МЩКТ) усім обстеженим виконували рентгенівську денситометрію (прилад Prodigy, General Electric). 10-річний ризик основних остеопоротичних переломів (FRAX-ООП) і переломів стегнової кістки (FRAX-СК) визначали за допомогою української моделі згідно з двома методиками (з використанням показників індексу маси тіла (FRAXIМТ) та МЩКТ (FRAXМЩКТ)). Результати. При аналізі розподілу показників FRAXIМТ-ООП у жінок залежно від наявності вертебральних переломів встановлено, що FRAXIМТ-ООП менше від 20 (межа, зазначена як критерій для початку лікування в американських рекомендаціях) зареєстровано в 100 і 100 % обстежених відповідно, а FRAXIМТ-СК менше від 3 (межа для початку лікування) — у 95 і 55 % (відповідно). Продемонстровано вірогідний помірний кореляційний зв’язок між показниками двох методик як у жінок без переломів в анамнезі, так і в пацієнток із вертебральними переломами для обох показників алгоритму — FRAX-ООП та FRAX-СК. Висновки. Вивчення особливостей показників FRAX у жінок залежно від наявності вертебральних переломів засвідчило вірогідне збільшення показників ризику як основних остеопоротичних переломів, так і переломів стегнової кістки з віком незалежно від використаної методики (з урахуванням показників ІМТ чи МЩКТ) у жінок як із вертебральними переломами, так і без будь-яких переломів в анамнезі. Вищезазначене слід враховувати при оцінці ризику остеопоротичних переломів у жінок у постменопаузі й плануванні лікувально-профілактичних заходів.

Wood quality is related to the characteristics and properties of this material. Understanding the factors that can impact the wood formation is fundamental in the indications for use. The aim of this study was to evaluate the influence of different planting densities on the wood quality and the radial profile on some physical and anatomical characteristics of young trees of Tectona grandis. Nine trees were evaluated in three planting densities: 6 x 2 m; 5 x 2 m; and 4 x 2 m. All trees were subjected to analysis of acoustic tomography, X-ray densitometry, and fiber characterization. Multivariate associations between the variables of interest were evaluated according to the planting spacing and the radial profile by principal component analysis. The results indicated that the wood characteristics of young teak trees are influenced, mainly, by the radial variation (pith-bark).

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.

Tectona grandis (teak) is an important commercial tree species that is widely used in tropical dendrochronology due to the formation of climate-sensitive annual growth rings. However, young trees growing in plantation conditions exhibit poor ring visibility during the first years of growth, limiting the dendrochronology application. In the present study, we use x-ray densitometry to determine the wood density profile between and within annual rings and at the sapwood-heartwood boundary in trees from fast-growth plantations. The resulting wood density profiles (WDP) can be categorized as uniform, stable growth, unstable growth, and false. The annual ring boundaries were indistinct in trees less than 8 years old. In mature trees, the annual ring boundaries are more defined. In relation to the sapwood-heartwood boundary, the WDP showed a decrease in the wood density; however, this decrease is influenced by the annual ring boundary when the two boundaries coincide. The identification of annual rings in trees growing in fast-growth plantations should be combined with X-ray densitometry and visual identification if wood density data are necessary for deriving other analysis, as climate change, from annual ring.

Trees that were killed and buried by volcanic eruptions can be used to date an eruption with annual or even sub-annual resolution. The detection and measurement of subfossil tree-ring widths (TRW), however, often remains challenging if the material was carbonized during the eruption. Here, we show that the application of X-ray densitometry can improve the assessment of charcoal. Measuring the wood density of carbonized trees killed by the Laacher See Eruption ~13,000 years ago, facilitates the identification of the outermost rings that were formed just before the eruption. Our results suggest that anatomical techniques should be routinely applied in the assessment of historical, archaeological and subfossil wood.

Stable attached partial cavitation in separated flows can transition to cloud shedding, and the mechanism of transition has been attributed to the presence of a re-entrant liquid jet. Our findings have revealed the presence of propagating bubbly shock waves as an alternative dominant mechanism of shedding when the compressibility of the bubbly mixture is appreciable. In the present paper, we discuss dynamics associated with these bubbly shock waves, interaction of shock waves with obstacles in their path, and means to manipulate their properties to control the shedding process by non-condensable gas injection.

The aim of the research was the determination of indices of mineral density of the spongy substance, mineral density of the cortical layer and also the cortical index according to the data of X-ray densitometry in infants at norm and at hip joint dysplasia. Materials and methods. Using the developed program „OsteoGraf-child”, there was carried out the analysis of x-ray photographs of hip joints of 56 children 0 days - 3 years old, suspected in trauma or HJD. Results of research. „OsteoGraf-child” program for the diagnostics of structural changes of a femur at norm and at hip joint dysplasia in infants allows to determine indices of the femur mineral density, for the spongy and compact substances separately, and to calculate the cortical index. Conclusions. Indices of the age norm of the mineral density of the spongy substance and femur cortical layer were established that allows to estimate objectively the bone tissue status in infants. At the conservative treatment of hip joint dysplasia using the long-term immobilization was detected the reliable decrease of indices of the spongy substance and cortical layer mineral density in infants of 6–12 months that needs a treatment correction

International audience; To maximize utilization of our forest resources, detailed knowledge of wood property variation and the impacts this has on end-product performance is required at multiple scales (within and among trees, regionally). As many wood properties are difficult and time-consuming to measure our knowledge regarding their variation is often inadequate as is our understanding of their responses to genetic and silvicultural manipulation. The emergence of many non-destructive evaluation (NDE) methodologies offers the potential to greatly enhance our understanding of the forest resource; however, it is critical to recognize that any technique has its limitations and it is important to select the appropriate technique for a given application. In this review, we will discuss the following technologies for assessing wood properties both in the field: acoustics, Pilodyn, Resistograph and Rigidimeter and the lab: computer tomography (CT) scanning, DiscBot, near infrared (NIR) spectroscopy, radial sample acoustics and SilviScan. We will discuss these techniques, explore their utilization, and list applications that best suit each methodology. As an end goal, NDE technologies will help researchers worldwide characterize wood properties, develop accurate models for prediction, and utilize field equipment that can validate the predictions. The continued advancement of NDE technologies will also allow researchers to better understand the impact on wood properties on product performance.

Average wood density of 38-year-old Cariniana legalis (Mart.) Kuntze, a Brazilian native forest species, was found to increase with faster growth and lower stocking, while decreasing from pith to bark. A complete randomised block design was planted with five blocks. Ten trees were harvested in each of three spacing treatments. We hypothesised that the stand stemwood production would not significantly differ depending on tree spacing. However, tree growth would be higher in the wider spacing and wood density would be higher in the narrower spacing. The diameter growth of trees was higher at 3 m × 2.5 m than at 3 m × 2 m and 3 m × 1.5 m. Nevertheless, this higher individual tree growth at 3 m × 2.5 m did not compensate for the greater tree stock density at 3 m × 1.5 m with stand stemwood production at 38 years of 530 m3 ha−1 and 649 m3 ha−1, respectively. These results suggest that C. legalis, which can produce up to 17 m3 ha−1 y−1 of medium- to high-density timber – about 800 kg m−3 – is a promising native species for forest plantations in Brazil.Keywords: Brazilian native wood, management of tropical timber, X -ray densitometry

The processing of subfossil wood poses some difficulties in densitometric research. Problems arise because of the physio-chemical changes of wood occurring in the sedimentation environment. Subfossil wood modification can result from the uptake of mineral and organic substances into the wood tissue. It can also occur as the effect of microbiological degradation of wood. The goal of this study was to identify the appropriate method of subfossil wood preparation for the densitometric research. For this purpose the wood of Norway spruce from Lake Schwarzensee was subjected to extraction in deionized water, acetone and diluted acetic acid. The application of acetic acid did not significantly influence the density of the wood and acetone seemed to be too aggressive. The best result was obtained by rinsing the samples in cold de-ionized water. This extraction procedure allowed removal of unwanted water-soluble, organic and inorganic compounds from wood and simultaneously did not lead to the degradation of subfossil samples.

The annual ring density of cross-sections of Japanese cedar stems of different ages has been recorded by X-ray density analyser in order to determine the boundary line between juvenile and mature wood. A particular emphasis was put on the tracheid length in the annual rings. The obtained data was analysed by using Wavelet transformation. It can be assumed that the process of formation of woody tissue is a periodic one and that the characteristic periods include several annual rings. This also indicates that the growth of a tree can be separated into distinct processes that can be identified within the juvenile and mature wood zones. It has been shown that the suggested numerical approach enables a rapid and reliable evaluation of the data.

X-ray densitometry is a technique often used in tree growth and wood quality studies to incrementally measure density (specific gravity) along a radial strip of wood. Protocols for this technique vary between laboratories because of differences in species, equipment, tree age, and other factors. Here, the application of X-ray densitometry is discussed in terms of a case study specific to the southern pines, whereby loblolly (Pinus taeda L), longleaf (Pinus palustris Mill.), and slash (Pinus elliottii Engelm.) pine wood cores were analyzed using an automated system. Objectives of this study included an assessment of the potential impacts on whole-core wood quality data from wood core extraction and use of two different demarcation methods (threshold and inflection point) for the earlywood–latewood transition. Wood core extraction before X-ray densitometry showed minimal impact on the shapes of individual ring profiles, and whole-core wood quality data were essentially unchanged. An assessment of the inflection point method employed for determining the earlywood–latewood transition point in the X-ray densitometry data demonstrated that the growth ring profiles for the southern pines are not amenable to polynomial fitting. Indeed, in the southern pines, the earlywood–latewood transitions are as equally abrupt as the latewood–earlywood transitions. Accordingly, a threshold density deemed appropriate to define the onset of a growth ring would be equally appropriate to define the onset of latewood formation.

Eucalyptus wood from adult trees is used for several purposes; however, the wood of younger trees has limited use. This study aims to characterize and propose uses of two-year-old eucalyptus wood. Six two-year-old Eucalyptus grandis × Eucalyptus urophylla clones have been selected and their anatomical, ultrastructural, physical and mechanical wood characteristics evaluated. The wood of Clone A shows more robust fibers with better microfibril arrangement, resulting in better mechanical properties, and therefore, a better performance for structural use. Clone F showed a low variation of wood basic density in the radial direction, facilitating its machinability, and with the Clone B, showed a lower anisotropy, and therefore, the wood is recommended for locations with high variations of humidity. The heterogeneity of the wood characteristics of the evaluated clones confirms the need for further studies, to choose those most adequate to each use. RESUMO A madeira de eucalipto de árvores adultas é utilizada para os mais diversos fins, entretanto, a utilização desta madeira de árvores de idade precoce é limitada. O objetivo foi caracterizar e propor utilizações para madeira de eucalipto com dois anos de idade. Seis clones de Eucalyptus grandis × Eucalyptus urophylla, com dois anos de idade, foram selecionados e suas características anatômicas, ultraestruturais, físicas e mecânicas avaliadas. A madeira do clone A apresentou fibras mais robustas e de melhor arranjo microfibrilar, resultando em melhores propriedades mecânicas e, por isto, melhor desempenho para uso estrutural. O clone F apresentou madeira com pouca variação da densidade básica no sentido radial, facilitando sua trabalhabilidade e, com o clone B, apresentou menor coeficiente de anisotropia e, por isto, a madeira é recomendada para locais com alta variação de umidade. A heterogeneidade das características da madeira dos clones avaliados corrobora a necessidade estudos por clone para uma sua melhor utilização.

An accurate, rapid, and convenient method is presented for moisture content (MC) determination of solid wood based on dual-energy X-ray absorptiometry (DXA). Poly(methyl methacrylate)-equivalent thicknesses (PMMA-EThs) of sugi (Cryptomeria japonica D. Don) wood blocks and pure water were measured by means of a wide range of X-ray tube voltages (20–100 kV). The ratio of the PMMA-ETh of pure water to that of wood decreased as X-ray tube voltage was increased, suggesting that an appropriate pair of tube voltages for DXA is 20 and 100 kV. According to this result, X-ray images of 30 wood samples were taken at 20- and 100-kV tube voltages, and their average PMMA-Eths from both images was determined. There was a strong negative correlation between the wet-basis MC of the wood sample and the ratio of its PMMA-Eth at 100 kV to that at 20 kV. A regression equation was developed for estimating the dry-basis MC of wood samples from their PMMA-ETh ratios. The standard error of estimate was 2.2%, which is better than those determined for electric moisture meters. This approach may lead to the development of a practical, nondestructive moisture meter for wood.

Currently, the radiation techniques are dominant in the diagnosis of osteoporosis, among them the dual-energy X-ray absorptiometry (DXA) is the leading. This method is based on the determination of bone mineral density. The article describes a computerized system Standart LS (Russia), which standardizes the parameters of bone mineral density, depending on the type of densitometry equipment and evaluates the results of X-ray densitometry taking into account a regional perspective. The developed program and population database of parameters of bone mineral density were the results of retrospective analysis of the dual-energy X-ray absorptiometry in 1504 women living in Kemerovo region. The dual-energy X-ray absorptiometry was performed with a bone densitometer Lunar-DPX-NT (GE Healthcare, UK). Initially, the bone mineral density of the first-fourth lumbar vertebrae was studied; then, the standardization of other parameters of densitometric systems was carried out (Hologic, Norland). The algorithm of the computer program consists of three phases: the introduction of parameters of bone mineral density, the standardization and the processing according to a type of densitometer and an age of a subject. After data processing, the values of Z-criteria are given out according to the recommendations of the International Society for Clinical Densitometry. The developed computerized system will contribute to a more accurate assessment of bone mineral density in the women, taking into account regional differences.

UNESP - Universidade Estadual Paulista 'Julio de Mesquita' Filho Faculdade de Ciencias Agronomicas, Caixa Postal 237

A tipuana (Tipuana tipu) foi muito utilizada na arborização urbana. De maneira geral, o manejo inadequado expõe o lenho à ação dos fungos e insetos xilófagos, muitas vezes associados à queda da árvore. Portanto, com este trabalho, objetivou-se caracterizar as propriedades físico-mecânicas do lenho sadio e biodeteriorado por fungos apodrecedores em árvores de tipuana da arborização urbana da cidade de São Paulo-SP. Treze árvores com deterioração no lenho foram suprimidas. Da base do tronco foram cortados toretes de 1 m de comprimento para a caracterização das propriedades físico-mecânicas dos lenhos sadio e deteriorado. Os resultados indicaram que, por meio do perfil radial de densidade por densitometria de raios X, foram identificados sete padrões de biodeterioração do lenho, sendo, (EXS) com acúmulo de extrativos e sadio, (ZR) com zona de reação e sadio, (NS) normal e sadio, (PB INC; PB INT) podridão branca incipiente ou intensa e (PM INC; PM INT) podridão mole incipiente ou intensa, com densidades 0,94, 0,92, 0,82, 0,66, 0,41, 0,67 e 0,44 g.cm-3, respectivamente. Os ensaios mecânicos evidenciaram os lenhos (ZR) (EXS) com os maiores valores de resistência e rigidez de 84 e 80 MPa e 6461 e 5826 MPa, respectivamente; o lenho (NS) apresentou valores de 62 e 4642 MPa e os padrões (PB INC) (PM INT) os menores e significativos valores de resistência e rigidez, destacando o (PB INT) com valores de 5 e 571 MPa. A redução dos valores de densidade, resistência e rigidez do lenho esteve relacionada com a biodeterioração da parede celular das células das árvores de tipuana pelos fungos apodrecedores. The tipuana was widely used in urban arborization. In general, inadequate management exposes the wood to the action of wood decaying fungi and insects, often associated with the fall of the trees. The aim of this study was to evaluate the physical and mechanical properties of sound and rotten tipuana wood from São Paulo City´s afforestation. Thirteen old trees with symptoms of wood deterioration were removed. From the basal region of the trunk were cut 1 m-length stem segments, to characterize the physical and mechanical properties of sound and decayed wood. The results indicated that through the radial wood density profile by X-ray densitometry were classified seven pattern of wood biodeterioration, named (EXS) with accumulation of extractives and sound, (ZR) with the reaction zone and sound, (NS) normal and sound, (PB INC; PB INT) incipient and intense white rot (PM INC; PM INT) incipient and intense soft rot, with apparent densities of 0.94, 0.92, 0.82, 0.66, 0.41, 0.67 and 0.44 g.cm-3, respectively. The mechanical tests showed that wood classified as (ZR) (EXS) presented the highest values of strength and stiffness of 84 and 80 MPa and 6461 MPa and 5826, respectively; the (NS) showed values of 62 and 4642 MPa, and the (PB INC) (PM INT)the significant and lowest values of strength and stiffness, enhancing (PB INT) with values of 5 and 571 MPa. The reduction of density, strength and stiffness of wood is related to the biodeterioration of wood cell walls of trees tipuana by decaying fungi.

The relationships between climate and wood density components, i.e., minimum ring density, maximum ring density and mean ring density have been studied mainly in dominant trees. However, the applicability of the findings to trees of other dominance classes is unclear. The aim of this study was to address whether climate differentially influences wood density components among dominance classes. X-ray densitometry data was obtained from 72 black spruce (Picea mariana (Mill.) B.S.P.) trees harvested in Northwestern Ontario, Canada. Dominant, co-dominant and intermediate trees were sampled and the data analysed using mixed-effect modelling techniques. For each density component, models were first fitted to the pooled data using ring width and cambial age as predictors, before monthly climatic variables were integrated into the models. Then, separate models were fitted to the data from each dominance class. In general, the addition of climatic factors led to a small but significant improvement in model performance. The predicted historical trends were well synchronized with the observed data. Our results indicate that trees from all dominance classes in a stand should be sampled in order to fully characterize wood density-climate relationships.

International audience; & Context Wood density variation affects structural timber performance and is correlated with several potentially con-founding factors, such as cambial age, position in the stem and growth rate. To date, these relationships have not been com-prehensively quantified in black spruce (Picea mariana (Mill.) B.S.P.). & Aims The aim of this study was to describe the variation in annual ring density in black spruce as a function of cambial age, stem height and growth rate. & Methods Radial density profiles from 107 black spruce trees were analysed using a two-stage modelling approach. First, the parameters of a nonlinear function were estimated separately for individual samples. Linear regression was then used to model the parameters obtained in the first stage as functions of internal and external tree descriptors. & Results Annual ring density was high near the pith and declined rapidly in the first 15 annual rings before increasing to more stable values between rings 25 and 60. However, just below 25 % of the samples showed a gradual decline towards the bark, typically after ring 60. & Conclusion Describing and quantifying radial density pat-terns, including the decline close to the bark, will help further our understanding of the links between tree growth and ring density over the life of the tree.

The hydrodynamics near the base of a 15 cm i.d. fluidized-bed dryer having perforated, punched, and porous plate distributors have been studied using one-dimensional X-ray densitometry imaging. The time-averaged solids concentration profiles of dry pharmaceutical granule and wet granule undergoing drying were compared. The porous plate creates good gas distribution over the bed cross section with dry granule but results in defluidization at the distributor level when the granule is wet. The perforated and punched plates exhibit different solids concentration profiles with dry granule; however, the presence of moisture results in similar hydrodynamics between the plates during drying. Standard deviation analysis of the high-frequency solids concentration data was used to corroborate the results of the time-averaged solids concentration measurements.

Excessive abdominal fat contributes to the development of chronic nontransmissible diseases. Dual emission X Ray absorptiometry (DXA) is a simple to administer technique that allows abdominal fat percentage (%abdominalFDXA) to be determined. Anthropometric measurements, which have been validated and are of low cost, such as the abdominal circumferences 2.5cm above the umbilical scar (ABC2,5) and level with the umbilical scar (ABCum), are used as indicators of abdominal fat. Skin folds (SF) are little used for this purpose. The objective of this study was to verify which of these anthropometric indicators best correlates with and best explains abdominalFDXA. The sample was made up of 22 women (43.9±11.6 years; 34.7±8.3 %G totalDXA) and 18 men (31.9±11.6 years; 19.0±8.0 %G totalDXA) who were measured for ABC2.5, ABCum, suprailiac SF (SI), midaxillary SF (AM) and abdominal SF (AB), while abdominalF (L1-L4) was measured by DXA. Pearson’s correlation and multivariate linear regression (“enter” method) were employed to verify the anthropometric measurements’ correlations and percentage of explanation with relation to abdominalFDXA. Strong correlations and significant levels of explanation (pResumoO excesso de gordura abdominal contribui no desenvolvimento de doenças crônicas não-transmissíveis. A absortometria de raio-X de dupla energia (AXDE) é uma técnica de simples aplicação, que permite a mensuração do percentual de gordura abdominal (%G abdominalAXDE). As medidas antropométricas, validadas e de baixo custo, como os perímetros abdominal 2,5cm acima da cicatriz umbilical (PAB2,5) e ao nível da cicatriz umbilical (PABum), são empregadas como indicadores de gordura abdominal. As dobras cutâneas (DC) são pouco estudadas nesse sentido. Assim, o objetivo desse estudo foi verificar quais destes indicadores antropométricos mais se correlacionam e explicam o %G abdominalAXDE. A amostra foi composta por 22 mulheres (43,9±11,6 anos; 34,7±8,3 %G totalAXDE) e 18 homens (31,9±11,6 anos; 19,0±8,0 %G totalAXDE) submetidos à mensuração dos PAB2,5, PABum, DC suprailíaca (SI), axilar medial (AM), abdominal (AB), e %G abdominal (L1-L4) por AXDE. Correlação de Pearson e a regressão linear múltipla (método enter) foram empregadas para verificar a correlação e o percentual de explicação das medidas antropométricas em relação ao %G abdominalAXDE. Correlações fortes e explicações significativas (p

Neutron imaging is a new non-destructive testing method in wood science. It is similar to X-ray methods but with differing sensitivities for different elements. In this study, neutron imaging was used to ascertain the density profiles of thin spruce samples and compared with results generated with standard X-ray microdensitometry. Data obtained through neutron imaging were similar to those resulting from the X-ray method. The advantage of neutron imaging is its higher sensitivity to some elements such as hydrogen. Together with the high neutron-sensitivity of the applied detectors (imaging plates) this makes shorter exposure times possible, and yields more detailed information on the inner composition of wood. X-ray film, which is still most commonly used in X-ray densitometry, has the disadvantage that the relationship between the optical density of the film and the density of wood is non-linear. This means that corrections and calibration with step wedges are necessary, whereas with neutron imaging the digital values can be used directly to calculate the density at a certain point of the specimen. Thus neutron imaging appears to be an appropriate method, which can be used as complement to established X-ray methods for fast and straightforward investigations of tree rings, growth zones and wood density.

The genus Larix is exceptional for its high content of extractives in the heartwood, with the dominating component arabinogalactan found abundantly in cell lumens of tracheids. On samples prepared from 100 European larch (Larix decidua Mill.) and hybrid larch (L. decidua × Larix kaempferi (Lamb.) Carr.) trees, extractive contents and wood density were measured using X-ray densitometry. A strong relationship between the amount of hot water extractives and the loss of density owing to the extraction process was found. Prior to extraction, increasing extractive content went hand-in-hand with higher wood density. At the heartwood–sapwood boundary, the density level dropped. After acetone and hot water extraction, the drop was no longer visible. Without proper consideration of the extractives in larch growth sites, comparisons in wood quality studies looking at wood density differences may become faulty, breeding studies could lead to incorrect selection strategies, and tree-ring studies may not deliver the expected climatic signals. Hence, hot water extractions should take place prior to radiation exposure.

Background: We conducted a survey to examine the difference in metacarpal bone mineral density (BMD) associated with the duration of walking and participation in habitual exercise in order to assess the benefits of walking for the prevention of bone loss in Japanese women. Methods: The subjects were 1873 healthy women (premenopausal, n = 1502; postmenopausal, n = 371), aged 18–72 years, who were screened for osteoporosis at health-care centers. They were classified into pre- (n = 1502), early post- (0–5 years since menopause, n = 195) and late post-menopausal (6–20 years since menopause, n = 176) phases. The metacarpal BMD was measured by computer-assisted X-ray densitometry. Subjects completed a questionnaire on lifestyle factors that included habitual exercise and daily walking time. To consider the factors of aging and physical characteristics, the BMD of all subjects was adjusted for age and height using a multiple non-linear model based on the data for premenopausal women. Results: anova indicated significant differences in adjusted BMD (BMDadj) in all menopausal phases according to walking duration and whether or not habitual exercise was engaged in. Premenopausal and early postmenopausal women who walked for over 30 min a day had a significantly greater BMDadj than those walking for less than 30 min (2.743 vs 2.684 mm thickness of an aluminum equivalent [mm Al]; and 2.711 vs 2.597 mm Al, respectively). Late postmenopausal women who walked for over 120 min had a significantly greater BMDadj than those walking under 30 min per day (2.746 vs 2.539 mm Al). Conclusion: These findings suggest that daily walks of more than 30 min also affect the metacarpal BMD, which is a non-weight bearing site, although walking over 120 min seems required to benefit late postmenopausal women. We conclude that such daily walks appeared to be beneficial in maintaining BMD in Japanese women.

Objectives: Although BMI (kilograms per meter squared) is widely used as a surrogate measure of adiposity, it is moderately associated (r ∼ 0.3) with height among children. We examined whether the resulting preferential classification of taller children as overweight, based on a BMI ≥95th percentile, is appropriate. Research Methods and Procedures: We assessed the cross-sectional relation of height among 5- to 18-year-old subjects (n = 1180) to levels of BMI, the sum of 10 skinfold thicknesses, and percentage body fat as determined by DXA. Results: The prevalence of a BMI level ≥95th percentile was substantially higher among 5- to 11-year-old subjects who were relatively tall for their age than among shorter children. Among 5- to 8-year-old boys, for example, each SD increase in height-for-age was associated with a 4.6-fold increase in the prevalence of overweight (p < 0.001). Height not only was associated with BMI but also showed similar correlations with the skinfold sum and with percentage body fat; furthermore, the magnitudes of these associations decreased with age. We also found that the association between percentage body fat and BMI (r = 0.85 to 0.90) was close to the maximum correlation that can be achieved by any weight-height index. Discussion: The use of BMI, which preferentially classifies taller young children as overweight, is appropriate because height and adiposity are correlated before the age of 12 years.

Resume Objectif. – La corticotherapie diminue la masse osseuse et altere la qualite de l’os. Ce travail a eu pour but d’evaluer l’atteinte osseuse cortico-induite par les techniques d’absorptiometrie biphotonique a rayons X (Dexa) et d’ultrasons, dans une population de patients traites par corticoides, avec ou sans fractures, en comparaison avec une population temoin. Methodes. – Nous avons evalue 34 patientes, âgees de 58 ± 14 ans (moyenne ± deviation standard), traitees par de faibles doses de prednisone depuis au moins 6 mois et qui n’avaient jamais recu de traitement anti-osteoporotique. La densite minerale osseuse (DMO) a ete mesuree par Dexa aux sites suivants : corps entier, rachis lombaire, col du femur. La morphometrie vertebrale a ete evaluee par la Dexa. Les parametres etudies par ultrasons (appareil Achilles Plus System) au calcaneum ont ete : la vitesse du faisceau ultrasonore (SOS), l’attenuation des ultrasons (BUA) et l’index de resistance. Quarante-deux femmes indemnes de toute pathologie osseuse ont servi de sujets temoins. Resultats. – Les parametres osseux, tant densitometriques qu’ultrasonores, etaient significativement diminues chez les patientes en comparaison aux temoins : DMO du corps entier (p Conclusion. – Dans notre etude, la mesure ultrasonore du BUA au calcaneum a ete la plus performante pour detecter les alterations du tissu osseux et pour evaluer le risque fracturaire chez des patients recevant une corticotherapie prolongee.

The ring width–wood density relationship (RW–WDR) is somewhat controversial. Most of the literature reports negative, but weak relationships, while others found no significant relationships at all. This study analyses the RW–WDR using a dataset of twenty even-aged Norway spruce trees grown at two different levels of air pollution in the Eastern Ore Mountains, Germany. Ring width, latewood proportion and wood density were measured in each tree ring. The year-to-year (temporal) variability of the RW–WDR was calculated by sequentially taking the rings grown in the same calendar year in trees within a site. In addition, RW–WDR was also calculated across tree rings (pith to bark) of given trees. During the observed period, the temporal RW–WDR fluctuated between negative and positive correlations with certain climatic patterns, as well as forest operations, playing a prominent role. It was shown that increased late-season rainfall favoured a more positive relationship. The temporal RW–WDR illustrated, for given trees of a site, that smaller rings formed in certain years might be related to higher wood density while other years may result to lower wood density. This finding is useful for an improved understanding regarding the effect of ring width on wood density.

Defining the transition from earlywood to latewood in annual rings is an important task since the accuracy of measuring wood densi- ty and ring width components depends on the definition. Mork's index has long been used as an anatomical definition of the transition from ear- lywood to latewood. This definition is arbitrary and extremely difficult to apply to X-ray densitometry. For X-ray densitometry, a threshold density of between 0.40 to 0.55 g cm -3 , depending on species, has been chosen to differentiate between earlywood and latewood density, but this method has shortfall. Therefore, new methods need to be developed and integrated into the computational programs used to generate X-ray den- sitometry data. In this study, we presented a mathematical method. We modelled the intra-ring wood density profiles in 100 plantation-grown black spruce (Picea mariana (Mill.) B.S.P.) trees using high order polynomials. The correlation between the predicted and the measured densi- ties is very high and highly significant. Based on this model, we define the transition from earlywood to latewood as the inflexion point. Results indicate that wood density at the earlywood-latewood transition point varies from juvenile to mature wood. This method could be easily integra- ted into any X-ray densitometry program and allows to compare individual rings in a consistent manner. transition / earlywood / latewood / X-ray densitometry / wood density / black spruce / modelling

The evaluation of regional myocardial blood flow (RMBF) during cardiac catheterization is of particular diagnostic interest. The purpose of this investigation was to validate x-ray densitometric parameters for the evaluation of RMBF. In five anesthetized dogs, arterial flow in the circumflex coronary artery was measured continuously with an electromagnetic flowmeter, and RMBF was determined by colored microspheres. Five different perfusion levels were created by mechanical obstruction of the coronary artery or by intravenous infusion of adenosine. At each steady-state perfusion level, digital subtraction coronary angiograms were obtained for densitometric analysis. Results documented a close correlation between the related time parameters 1/Mean Transit Time (1/MTT, r2 = 0.969), and 1/Rise Time (1/RT, r2 = 0.965) and RMBF over a wide range between 0.36 ml/(min x g) and 11.16 ml/(min x g). Maximum myocardial contrast density (Imax) also showed a good, but inverse correlation (r2 = 0.889) with RMBF and, therefore, did not reflect vascular volume. Contrast medium Appearance Time (AT) showed no correlation to RMBF (r2 = 0.017). Repeat densitometric measurements for different perfusion levels revealed a good reproducibility for MTT (accuracy: 0.001 s; precision: 0.447 s or 6.7 %) and RT (accuracy: 0.014 s; precision: 0.202 s or 10.4 %), while AT (accuracy: 0.072 s; precision: 0.420 s or 68.5%) and Imax (accuracy: 0.022 GL; precision: 1.197 GL or 44.5%) showed substantial variation. Myocardial perfusion reserve (MPR) calculated from RT (r2 = 0.90) or MTT (r2 = 0.94) showed better correlations to RMBF reserve than MPR calculated from AT (r2 = 0.04). In conclusion, only 1/MTT and 1/RT showed a good reproducibility and a close correlation to RMBF. Therefore, only these parameters can be recommended for calculations of RMBF and its reserve under clinical conditions.

安定期血液透析患者53名 (男性20名, 女性33名, 平均年齢53歳, 平均透析期間9.3年) を対象にPTHで二群に分け, CXD法により橈骨骨塩量, ΣGS/Dを, DXA法により橈骨, 腰椎正面, 頭部骨塩量を12か月間隔で2年間経時的に測定した. さらに研究開始時のCXD法で測定した橈骨骨塩量とDXAで測定した各種骨塩量との相関を算出し, これからCXD法による橈骨骨塩量のもつ透析患者骨塩量評価上の意義を検討した.CXD法による橈骨骨塩量は男女とも12か月以降有意に低下し, 低下は主としてPTH高値群に認められた. DXA法による橈骨骨塩量やΣGS/Dは, 女性ではCXD法による橈骨骨塩量と同様の変化を示したが, 男性ではPTHにかかわらず両群いずれも有意な骨量低下を検出できなかった. また, 骨塩量の年間減少率は男女いずれもCXD法による橈骨骨塩量がDXA法による橈骨骨塩量に比較して有意に高値であった. CXD法による橈骨骨塩量にはDXA法で測定した骨塩量のうち, 橈骨, 上肢, 全身骨塩量などの皮質骨塩量と高い相関が認められた. 腰椎正面骨塩量との相関は男性に比して女性で高く, 女性ではPTHにかかわらず高い相関を認めた. 今回測定した各種骨塩量と年齢との相関は認めなかったが, CXD, DXA法による橈骨骨塩量は透析期間と負の相関を示した. 以上の成績から, CXD法による橈骨骨塩量は他の骨塩量測定法に比し皮質骨塩量のみならず海綿骨塩量の変化をも鋭敏に反映し, 透析患者の骨塩量評価において皮質骨, 海綿骨両者の変化を総合的に評価する有用な検査法と考えられた.

We studied the relation between performance of activities of daily living and X-ray findings of osteoarthritis of the knee in aged persons. We made Covariance Structure Analysis models of knee pain, X-ray findings and bone mineral density as measured by computed X-ray densitometry. The subjects were 257 women aged from 47 to 88 years who were outpatients at an orthopedic clinic. The best-fit model indicated that loss of bone mineral density in metacarpals was associated with X-ray findings of knee-joint degeneration, as well as with knee pain. No relationship was found between knee-joint degeneration and knee pain. These results suggest that bone mineral density should be taken into consideration when interpreting X-ray findings of knee pain. This model incorporates the effects of degeneration of the subchondral bone. In summary, we should use measurements of bone mineral density along with X-ray findings for the diagnosis and treatment of knee osteoarthritis. We may be able to precisely predict knee pain caused by osteoarthritis, by analysis of a model that includes a lesion in joint cartilage.

To measure the void fraction distribution in gas-liquid flows, a two-dimensional x-ray densitometry system was developed. This system is capable of acquiring a two-dimensional projection with a 225 cm2 area of measurement through 21 cm of water. The images can be acquired at rates on the order of 1 kHz. Common sources of error in x-ray imaging, such as x-ray scatter, image distortion, veiling glare, and beam hardening were considered, and mitigated. The measured average void fraction was compared success fully to that of a phantom target and found to be within 1%. To evaluate the performance of the new system, the flow in and downstream of a ventilated nominally two-dimensional partial cavity was investigated and compared to measurements from dual tip fiber optical probes and high speed video. The measurements were found to have satisfactory agreement for void fractions above 5% of the selected void fraction measurement range. Office of Naval Research under grant N00014-10-1-0974

Introduction of X-ray densitometry had revolutionized the diagnostics of osteoporosis. Majority of scientists believed that it was a diagnostic instrument close to almost ideal one capable evaluation of both: bone mineral density and likelihood of future fractures. Experiences accumulated during the previous years have slightly shaken this belief. It is more frequently heard that DEXA is not an ideal diagnostic instrument, but no better instrument has been created yet, which is also proved by our 12 years of experience. Materials and Methods. X-ray densitometry research evaluated 5200 patients aged 40-70. 4100 women and 1100 men. Medical History of 825 patients showed that they had bone fractures, 136 out of them were high energy ( pressure), the rest of them low trauma or no-trauma fractures. BMD index was low in 2736 patients (T score> -2.5). 48 patients had fractures in earlier lives registered in their medical records. Results. Low BMD index was identified in 2736 patients with osteoporosis only during the DXA lateral scans. It is arguable thatx-ray densitometry and BMD evaluation is the only criteria for the standards of diagnostics and the predictor of progressive bone loss and fractures. Discussion. While analyzing the results, diagnostic problems emerged at diagnostic process were taken into account, namely spine deformation, osteoporosis, osteochondrosis that camouflage real mineral density of the bones. At the same time, each patients with existing fractures in their record filled in special questionnaires describing clinical symptoms of the disease and risk-factors influencing the likelihood of the disease. Results of the work were processed through the analysis of variance (Fisher). Reliable correlation was not identified between DXA results and fracture risk index. This last one encourages routine use of FRAX in diagnostics of osteoporosis and prognosis of fractures before morphological evaluation of bones will be readily available to use as an additional diagnostic tool.

Background Low bone mass at metacarpal (MC) diaphysis measured by radiogrammetry (DXR) has been described as a poor prognostic factor in rheumatoid arthritis (RA). However, this technique is not available in our environment. Our group has previously described the measurement of bone mineral density (BMD) at metacarpophalangeal joints (MCP) by dual X-ray absorptiometry (DXA). This measurement showed an acceptable correlation with the DXR at MC bones. However, DXR at MC bones mainly assesses cortical bone, whereas DXA at MCP mainly analyzes trabecular bone. Therefore, we have developed a procedure to evaluate MC9s (2nd to 4th) bone mass of the nondominant hand through DXA. Objectives To study the correlation between BMD at 2nd to 4th MC of the nondominant hand measured by DXA with data obtained by DXR. Methods We studied 171 patients belonging to the Princesa Early Arthritis Register Longitudinal (PEARL) Study (84% women, 55.4 years at symptoms onset; 56.7% fulfilled RA 2010 criteria; 52% RF+ and 43.5% ACPA+). Demographic, clinical and laboratory data were collected per protocol. Hand X-rays were performed at baseline and after one year of follow-up, as well as nondominant hand BMD assessment by DXA (Hologic © QDR4500, Elite). The standard Hologic © software allows to design regions of interest (ROI) tailored to the researcher needs. In order to develop ROIs in DXA similar to that in DXR, the ROI generator was placed on every MC mid third of the diaphysis (aprox 17x17 mm). The ROI was rotated to be aligned to the MC longitudinal axis, avoiding overlap between adjacent ROIs. The BMD by DXA was the average of 3 successive measurements. The BMD by DXR was measured with standardized software Sectra (Linkoping, Sweden) on hand digital X-ray (GE © DX Definium 8000). Statistical analysis was performed using Stata 12 for Windows, including linear correlations according to the Spearman test between the BMD values of MC by DXA and DXR and BMD by DXA at global hand and MCP joints. In addition, a multivariate analysis was performed to determine which variables accounted for the differences between MC bone mass measured by DXR and DXA. Results 248 BMD measurements (154 at baseline and 94 at second visit) of the 3 regions described whose values are shown in Table 1. Conclusions As shown in table 1, MC bone mass measured by DXA shows the lowest absolute difference and the best correlation with MC bone mass by DXR. Female gender (beta coefficient =0.013; p=0.039), patients older than 65 years (beta coefficient =0.014; p=0.019) and patients with higher body mass index (beta coefficient =0.002 by kg/m 2 ; p=0.019) were significantly associated with lower differences between the values of MC by DXA and DXR. Acknowledgement FIS PI12/01578 y PI14/00442, Fondo Europeo de Desarrollo Regional (FEDER) and PFIZER Spain. Disclosure of Interest I. Llorente Grant/research support from: Pfizer Spain, L. Merino: None declared, A. M. Ortiz: None declared, S. Gonzalez: None declared, E. Escolano: None declared, J. A. Garcia Vadillo: None declared, E. F. Vicente: None declared, R. Garcia Vicuna: None declared, I. Gonzalez Grant/research support from: Pfizer Spain, S. Castaneda Grant/research support from: Pfizer Spain

MD法を改良したCXD法を男性血液透析患者125名の骨塩量評価に適用し, 同一患者のDXA法骨塩密度成績, 骨代謝関連臨床成績との関連について検討し, 同法の腎性骨異栄養症における臨床的有用性を検討した. 1年間の経過が観察された63名, 2年間の経過が観察された32名では経年変化も比較した.その結果, 1) CXD法ΣGS/D, MCI値はDXA法骨塩密度値と相関した. 相関係数は, 身体部位別には上肢との間で最も高かった. 2) CXD法ΣGS/D値と透析期間, Al値, ALP値, ALP3値, TRACP値との間に負の相関が認められた. 3) CXD法ΣGS/D値の1年間および2年間変化率はいずれもDXA法上肢骨塩密度値の同変化率に極めて類似していた. 4) 1年観察群のCXD法ΣGS/D値年間変化率はDXA法全身骨塩密度年間変化率と相関した. 5) 2年観察群の患者を二次性副甲状腺機能亢進症の重症度別にPTH-c値5ng/ml未満の18名 (A群) と同値以上の14名 (B群) に分けCXD法ΣGS/D値の推移を比較すると, B群のΣGS/D値は観察開始時よりA群より有意に低値であり, B群では経年的に低下し2年目で有意差に達した. 一方, A群では, このような低下はみられなかった.以上の成績から, CXD法のΣGS/D値はDXA法の上肢骨塩密度に類似した特性を持っており腎性骨異栄養症の骨塩量評価に有用で, 経過観察にも適した方法であると考えられた.

A method of making a visual display of subchondral mineralization in the major synovial joints is described. Unlike existing procedures, it can be used on the living subject. A modified application of computed tomography-densitometry, computed tomography-osteoabsorptiometry makes it possible to explore the mechanical adaptability to the prevailing mechanical force. This claim is based upon the comparison of information obtained from 20 anatomical specimens with CT-osteoabsorptiometry and x-ray densitometry of sections; both methods yielding virtually identical results. The distribution of the subchondral density was then expressed as a map of the articular surface with the aid of an image analyser. This method can make a useful contribution to basic clinical research, as well as providing a diagnostic technique which can also be used for observing progress after a corrective osteotomy or any other procedure causing a change in mechanical function. Examples of its use on living patients are given.

The results of dual x-ray bone densitometry in a patient with bilateral gluteal implants are presented. The patient underwent three measurements of the spine and hips, and one of them was before surgery. A baseline study showed mild osteopenia. After surgery, bone mineral density increased in both femoral necks, because of the superimposition of the implants. A spine phantom with and without a similar implant reproduced the findings in the patient. It is important to consider this type of surgery as a cause of potential bone mineral density artifact.