Circumferential variation in the relative density of lodgepole pine

1989 ◽  
Vol 19 (2) ◽  
pp. 276-279
Author(s):  
Josefina S. Gonzalez

The circumferential variation in the wood relative density of lodgepole pine (Pinuscontorta var. latifolia Engelm.) was examined in eight discs taken at breast height. The purpose was to determine if the present method of analyzing two opposite radial strips from pith to bark was sufficient for estimating the mean density of the disc. Results showed that two samples taken opposite each other would give comparable or better approximation of the mean density of the disc than would three or four samples taken at random.

2020 ◽  
Vol 58 (11) ◽  
pp. 1857-1864
Author(s):  
Elisa M. Castells ◽  
Aramis Sánchez ◽  
Amarilys Frómeta ◽  
Yanin Mokdse ◽  
Nelson Ozunas ◽  
...  

AbstractBackgroundIn Cuba, no screening program for cystic fibrosis (CF) has been implemented yet. The ultramicro enzyme-linked immunosorbent assay (UMELISA)® TIR NEONATAL has been developed for the measurement of immunoreactive trypsin (IRT) in dried blood spots on filter paper. The analytical performance of the kit was evaluated in the national network of laboratories.MethodsNewborn dried blood samples (DBS) were evaluated in 16 laboratories. An IRT/IRT/DNA protocol was followed using a cut-off value of 50 ng/mL. The mean, median and percentiles of the distribution were calculated and a two-sample t-test with unequal variance was used for statistical analysis. Influence of perinatal factors on IRT levels was analyzed.ResultsFrom January to June 2018, 6470 newborns were studied, obtaining a mean IRT value of 12.09 ng/mL (ranging 0–358 ng/mL) and a median of 8.99 ng/mL. Fifty-two samples (0.78%) were above the cut-off level and 16 samples (0.24%) were elevated in the re-screening process. One of them was confirmed positive by molecular biology (phe508del/c.3120 + 1G > A), constituting the first newborn screened and diagnosed early in Cuba. Second DBS samples were collected on average at 14 days and processed in the laboratory at 16 days of birth. Significant differences were observed (p < 0.05) when evaluating the influence of gender, birth weight (BW) and gestational age (GA) on the IRT values. Lower IRT concentrations were found in samples processed after 10 days of collection.ConclusionsThe performance of UMELISA® TIR NEONATAL in the laboratories has been satisfactory; hence CF newborn screening (NBS) was extended throughout the country from January 2019.


1990 ◽  
Vol 20 (2) ◽  
pp. 159-165 ◽  
Author(s):  
Brian W. Geils ◽  
William R. Jacobi

The comandra blister rust parasite (Cronartiumcomandrae Pk.) causes a serious canker disease of lodgepole pine (Pinuscontorta Dougl. ex Loud. ssp. latifolia (Engelm.) Critch.) in the central Rocky Mountains. The expansion, longevity, and distribution of comandra blister rust cankers were studied by annual monitoring, reconstructing canker histories, and random sampling. In saplings, infections occur throughout the lower 80% of the crown; and branch cankers expand toward the bole at 2.5 cm•year−1, regardless of temperature, age, position, tree size, vigor, or susceptibility to infection. The proportion of branch cankers that develop into stem cankers decreases logistically both with distance from infection site to bole and with time since infection. Fewer than 50% of branch cankers that are farther than 20 cm from the bole or more than 8 years old are expected to establish stem cankers. The proportion of branch cankers that become stem cankers decreases with distance more rapidly for comandra blister rust than for other stem rusts. The mean height of stem cankers increases with total tree height, but cankers are uncommon at the top of the crown and low on the trunk of larger trees. The number of years for a canker to girdle its host equals the diameter of the stem at the center of the canker measured in centimetres. Because girdling cankers develop infrequently, slowly, and predictably, potential losses from comandra blister rust can be reduced by timely and appropriate removal of damaged trees.


1969 ◽  
Vol 1 (3) ◽  
pp. 247-271 ◽  
Author(s):  
James Maxwell

In 1932 all 11-year-old children in Scottish schools were given a group intelligence test, and a sample of 1000 was individually tested. The future careers of this sample were followed till 1939. In 1968, 709 of the original sample could be traced, and data about education, employment, and family were obtained. In 1947, a parallel survey was conducted in Scotland, and a sample of 1208 children was individually tested, and followed up for 16 years. The same data about education, employment and family are available for the 1947 Sample.A comparison between length of school education indicates a greater proportion completing a full secondary education in the 1947 than in the 1932 Sample. Proportionally, more of the 1947 Sample graduated from university. In marriage, it is possible to cut across the 1932 Sample at the age of 27 years, to make direct comparison with the 1947 Sample at the same age. The greatest incidence of marriage is in the middle range of IQ, but later records for the 1932 Sample show a relative uniformity of marriage over the IQ range. The pattern for occupational class is similar. There is a slight tendency to later marriage in the 1932 Sample. Two measures of differential fertility for IQ are used. For both samples, there is a negative relationship between the mean IQs of the sample members and the number of their sibs, more marked for the 1947 Sample. The number of children born to members of the two samples before the age of 27 years shows a similar relationship, but in the following 20 years the pattern for the 1932 Sample changes to one with a peak of mean IQ at two children. It is suggested that linear differential fertility for IQ may be a function of the age of the parent.


2019 ◽  
Vol 10 (2) ◽  
pp. 125-135
Author(s):  
Jusuf Musić ◽  
Velid Halilović ◽  
Jelena Knežević ◽  
Admir Avdagić ◽  
Aida Ibrahimspahić ◽  
...  

Background and Purpose: Bark thickness and its share in the volume of roundwood are the most important characteristics of the bark, particularly in the process of timber harvesting, and during scaling of processed logs. Therefore it is very important to have at disposal relatively accurate data regarding these characteristics of bark for particular tree species. The main goal of this paper is to investigate the thickness of the bark and its share in the volume of roundwood of Norway spruce. Materials and Methods: The research was carried out in the area of the Canton 10 of the Federation of Bosnia and Herzegovina and it encompassed 393 trees of Norway spruce from 10 cm to 115 cm of thickness at breast height. Measuring of the mean diameter and double thickness of bark was conducted by section method. In total, 4,647 diameters and bark thicknesses were measured in different relative lengths of stems or in average 10.6 measurements per one stem. Results: As an optimal model for the evaluation of double thickness of the bark of Norway spruce depending on mean diameter of roundwood the function with designated determination coefficient of 0.7142 was selected. The obtained results have confirmed the previously defined relations of investigate characteristics, which are as following: a) with the increase of mean diameter of roundwood (section) double bark thickness is increased from 9.26 mm (thickness class 12.5 cm) to 31.65 mm (thickness class 92.5 cm); b) with the increase of mean diameter of roundwood the share of bark in its volume decreased from 14.26% (thickness class 12.5 cm) to 6.73% (thickness class 92.5 cm). Conclusions: By the actual method of estimating bark thickness or the share of bark in the volume of roundwood of Norway spruce in the forestry of the Federation of Bosnia and Herzegovina a significant error was created which increases with the increase of mean diameter. The obtained results point to the necessity of investigation of these bark characteristics in Bosnia and Herzegovina and represent an inevitable starting point for making adequate tables of bark thickness and its percentage share in the volume of roundwood of Norway spruce.


2014 ◽  
pp. 9-31
Author(s):  
Sinisa Andrasev ◽  
Savo Roncevic ◽  
Petar Ivanisevic ◽  
Sasa Pekec ◽  
Martin Bobinac

This paper presents the elements of growth of black locust trees and stands in 15 sample plots in Vojvodina, at the age of 21-68 years. In each sample plot, based on soil profile horizons the determined soil type was chernozem as well as its lower systematic units (subtype, variety and form), according to the Skoric et al. (1985) classification. On the basis of the mean stand heights (hL), the stands on the subtype of chernozem on loess and loesslike sediments belong to height classes I-IV, and stands on calcareous aeolian sand to classes II-V (according to R e d e i et al. 2014), which indicates their considerable variability with respect to productivity within the determined subtypes of chernozem. Significant differences at the level of chernozem subtypes were found between the mean heights (p = 0.032), but not between the mean diameters (p = 0.083). The mean diameters at breast height in the studied black locust stands were on average lower than the models of diameter growth for the appropriate height classes and determined by a larger number of trees per hectare than in the tables (R e d e i et al, 2014). The volume per hectare is higher than in the tables also being conditioned by the large number of trees per hectare.


Author(s):  
J. Caranqui ◽  
M. Ortíz

This research study contributes to the knowledge of the diversity and similarity of vegetation more than 5 cm diameter at breast height (DBH); the study was carried out in the montane forest located in Tungurahua, Pillaro, Baquerizo Moreno, Indiviso (01°18’S, 78°30’W), at an altitude of 30,400 m. A transect of 1000 m² was made, divided into 5 plots of 50×4 m. The species were identified by the ESPOCH Herbarium, and the values calculated were relative density (DR) and relative dominance (DMR) to obtain the Importance Index (IV). 18 families, 29 genera, and 33 species were found, corresponding to 249 individuals, in which the largest number of individuals were accounted for by Escallonia myrtilloides (8.03%), Macleania rupestris (7.63%), Vaccinium floribundum (6.02%), Gynoxis buxifolia and Miconia bracteolata with 5.62%, Bacharis teindalensis and Blechnum loxensis with 4.82%, and Maytenus vertillata, Hypericum laricifolium, Tibouchina lepidota, Brachyotum ledifolium, Sympoccos with 4.02%; the remaining species had lower values. The reason for finding both species of shrub paramo and high montane forest is not so clear, since physiognomically the area under study was a high montane forest. Furthermore, no studies have been conducted in other transition zones, but for this reason, a high number of species of two types of vegetation is found. Keywords: analogue flowering, shrub paramo, high montane forest, indiviso. Resumen El presente trabajo contribuye al conocimiento de la diversidad y similitud de la vegetación mayor de 5 cm de diámetro a la altura del pecho (DAP); el estudio se realizó en el bosque montano localizados en provincia de Tungurahua, cantón Pillaro, parroquia Baquerizo Moreno, sector Indiviso, en las ccordenadas 01°18’S; 78°30’W, altitud 30.400 m.s.n.m. Se realizó un transecto de 1000 m², divididos en 5 subtransectos de 50×4 m. Las especies se identificaron el Herbario ESPOCH, los datos calculados fueron Densidad relativa (DR), dominancia relativa (DMR) para obtener Indice de Importancia (IV). se encontraron 18 familias, 29 géneros, 33 especies que corresponden a 249 individuos, en las cuales el mayor número de individuos cuenta Escallonia myrtilloides (8,03%), Macleania rupestris (7,63%), Vaccinium floribundum (6,02%), Gynoxis buxifolia y Miconia bracteolata con 5,62%, Bacharis teindalensis y Blechnum loxensis con 4,82%, Maytenus vertillata, Hypericum laricifolium, Tibouchina lepidota, Brachyotum ledifolium, Sympoccos quítense con 4,02%; el resto con valores inferiores. La explicación de tanto especies de páramo arbustivo y bosque montano alto no están tan claros, ya que fisionomicamente fue un bosque montano alto esta zona en estudio. Además no se han encontrado estudios en otras zonas de transición, pero por ello se encuentra un número alto de especies de dos tipos de vegetación. Palabras clave: vegetación análoga, páramo arbustivo, bosque montano, indiviso.


Author(s):  
Priscila Lie Tobouti ◽  
Juliana Seo ◽  
Michella Bezerra Lima ◽  
Bruno Tavares Sedassari ◽  
Norberto Nobuo Sugaya ◽  
...  

<p><strong>Objective: </strong>To compare the diagnostic accuracy of immunohistochemistry compared to real-time PCR (using a simple phenol-chloroform DNA extraction protocol) in the detection of HHV8 in small oral biopsies of Kaposi sarcoma. Also to validate the use of this DNA extraction protocol to extract HHV8 DNA.</p><p><strong>Material and methods:</strong> Seventeen cases of oral KS were examined. Data including gender, age, and anatomic location were obtained from patient´s records and histological sections stained with hematoxylin and eosin (H&amp;E) were reviewed. Immunohistochemistry was used to detect HHV8 in lesions of interest, as well as real-time PCR.</p><p><strong>Results: </strong>All the patients were HIV positive, the mean age was 35.5 years old, and the affected oral sites were palate (47%), gingiva (29.4%), tongue (11.8%), lip (5.9%), and oral floor (5.9%). Fifteen samples showed positive staining for HHV8 and only two samples were negative. The same results were observed using real-time PCR HHV8-DNA detection.</p><p><strong>Relevance: </strong>Our findings suggest that immunohistochemistry is faster and cheaper to perform than real-time PCR and was shown to have similar levels of sensitivity and accuracy for detection of HHV8 even in small biopsies. Additionally DNA extraction using a non-commercial kit, as done in this study can further reduce the costs to a pathology service.</p>


Author(s):  
Cas W Weykamp ◽  
Theo J Penders ◽  
Frits A J Muskiet ◽  
Willem van der Slik

Stable lyophilized ethylenediaminetetra-acetic acid (EDTA)-blood haemolysates were applied in an external quality assurance programme (SKZL, The Netherlands) for glycohaemoglobin assays in 101 laboratories using 12 methods. The mean intralaboratory day-to-day coefficient of variation (CV), calculated from the assay of 12 unidentified pairs over a period of 1 year, was 5·2% (range: 0·2–28·7). Forty-seven per cent of laboratories did not meet the criterion of CV < 5%, whereas 68% did not meet the clinically more desirable 3·3–3·6%. Linearity, as derived from the analysis of five combinations of two haemolysates with low and high glycohaemoglobin percentages over 6 months, was excellent (mean correlation coefficient 0·9953; range: 0·9188–0·9999). Analysis of two samples with high and low glycohaemoglobin percentages gave mean interlaboratory coefficients of variation of 10% for one method performed by several laboratories and 22% for all methods performed by all laboratories. It is concluded that the majority of laboratories do not meet the clinically desirable intralaboratory precision and that an unacceptably high interlaboratory precision exists.


2008 ◽  
Vol 54 (No. 7) ◽  
pp. 321-332 ◽  
Author(s):  
P. Kantor

: The study evaluates production parameters (height, diameter at breast height, volume) of Douglas fir (<I>Pseudotsuga menziesii</I> [Mirb.] Franco) at mesotrophic sites of the Křtiny Training Forest Enterprise in mature stands. In total, 29 mixed stands were assessed with the registered proportion of Douglas fir at an age of 85 to 136 years. Comparing the 10 largest Douglas firs with the 10 largest spruces or larches higher, and as a rule markedly higher, production potential of introduced Douglas fir was found in all assessed stands. There were also groups of trees where the volume of Douglas fir was twice to 3 times higher than the volume of spruce or larch (see Tabs. 5 to 10). For example, in stand 177B11, the mean volume of 9.12 m<sup>3</sup> was recorded in the 10 largest Douglas fir trees but the volume of spruce reached only 3.17 m<sup>3</sup> and the volume of larch was 3.70 m<sup>3</sup>. Differences in mensurational parameters of Douglas fir found on the one hand and of Norway spruce (<I>Picea abies</I> [L.] Karst.) or European larch (<I>Larix decidua</I> Mill.) on the other hand compared by ANOVA tests were statistically highly significant. Annual ring analyses have shown that at present the volume increment of particular Douglas fir trees ranges from 0.12 to 0.16 m<sup>3</sup> per year in mature stands (i.e. about 1.5 m<sup>3</sup> every 10 years).


1973 ◽  
Vol 56 (5) ◽  
pp. 1164-1172
Author(s):  
Milan Ihnat ◽  
Robert J Westerby ◽  
Israel Hoffman

Abstract The distillation-spectrophotometric method of Hoffman for determining maleic hydrazide has been modified to include a double distillation and was applied to the determination of 1–30 ppm maleic hydrazide residues in tobacco and vegetables. Recoveries of 1–23 μg added maleic hydrazide were independent of weight of maleic hydrazide, but did depend on sample and sample weight. The following recoveries were obtained from 0.5 g sample: pipe tobacco, 84%; commercially dehydrated potato, 83%; cigar tobacco, 81%; dried potato, 76%; fluecured tobacco, 73%; dried carrot, 71%. In the absence of sample, the recovery was 82%. When appropriate standard curves were used, maleic hydrazide levels determined in tobacco samples were essentially independent of sample weight in the range 0.1–3 g. The mean relative standard deviation for a variety of field-treated and fortified tobacco samples containing 1–28 ppm maleic hydrazide was 3%. The precision and sensitivity of this procedure seem to be substantial improvements over official method 29.111–29.117. It is recommended that the present method be subjected to a collaborative study.


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