Frost hardiness of commercial Eucalyptus species at different elevations

1989 ◽  
Vol 19 (10) ◽  
pp. 1235-1239 ◽  
Author(s):  
P. M. Hallam ◽  
J. B. Reid ◽  
C. L. Beadle

Six Eucalyptus species, E. regnans F. Muell., E. delegatensis R.T. Bak., E. globulus Labill., E. nitens (Deane & Maid.) Maid., E. pauciflora Sieb. ex Spreng, and E. grandis Hill ex Maid., were sampled for determination of frost hardiness in March (late summer) and August (late winter) 1985 from trial plantings at four elevations in southern Tasmania. In March, there was a statistically significant difference between sites, but not between species or provenances. In August, significant differences between species, and for E. delegatensis between provenances, had developed. The species ranked in order of increasing frost hardiness as follows: E. regnans < E. grandis < E. globules = E. delegatensis (Maydena provenance) < E. pauciflora < E. nitens < E. delegatensis (Guildford provenance). Greatest frost hardiness was developed at the 60-m site (elevation), followed by (in decreasing order) the 650-m site, the 440-m site, and the 240- m site. This order corresponded to the minimum temperatures experienced at the sites. Conversely, greatest growth occurred at the 60-and 240-m sites followed by the 440-m site and then the 650-m site, corresponding to decreasing maximum temperatures. It is argued that good growth and productivity are possible on quite frost prone sites, provided suitable provenances are selected for planting.

1988 ◽  
Vol 18 (5) ◽  
pp. 595-600 ◽  
Author(s):  
P. M. Hallam ◽  
W. N. Tibbits

An electrical conductivity method for determining frost hardiness of tissue discs punched from Eucalyptus leaves is described. Samples were exposed to convective heat loss in an air-filled chamber. Rates of cooling and desired frost temperatures were electronically controlled and maintained. Supercooling of tissue was effectively eliminated by addition of small amounts of AgI and water. Conductivity of diffusate was measured as a means of quantifying tissue damage following frost. Relative conductivity was determined with reference to subsequent measurements following heating the discs to 70 °C which resulted in maximum conductivity. Exposure of leaf discs to temperatures below the lethal temperature for these species (<−10 °C) resulted in similar maximum conductivity readings. The technique is evaluated to assess its potential to distinguish small differences in frost hardiness caused by genotype and environment. For both E. delegatensis and E. nitens there was no significant difference in frost hardiness expressed in terms of mean lethal temperature when comparing leaf discs with frosting whole seedlings.


1969 ◽  
Vol 53 (3) ◽  
pp. 177-186 ◽  
Author(s):  
Juan A. Bonnet

Twenty-six young coffee trees grown under shade in an acid upland soil of 2 farms were selected representing 3 varieties and 2 yield-groups. The yield data were recorded for the crop harvested in the fall of 1962 from 15 highyielding and 11 low-yielding trees. Young leaves from each tree were sampled in the late summer of 1961 and in the late winter of 1962. The following 10 essential plant nutrients were determined: N, P, K, Ca, Mg, Mn, Fe, B, Zn, and Cu; as well as 2 nonessential elements, Na and Al. The yield and leaf-composition data were analyzed statistically. The high-yielding trees produced 2.6 times as much coffee as the lowyielding ones, a highly significant difference. There was no significant difference between the mean yields of the varieties. "Highly significant" or "significant" mean differences were obtained in all the essential nutrients except zinc, in the coffee leaves, between varieties; in the nutrients: N, P, K, Ca, Mg, and B, between seasons; and only in Ca and Mg between yield-groups. The acid soil, Alonso clay, is high in exchangeable manganese and in aluminum; the coffee trees used here also contained high Mn and Al in their leaves.


1980 ◽  
Vol 28 (6) ◽  
pp. 499 ◽  
Author(s):  
R Sinclair

Water potential and stomatal conductance were measured for three eucalypt species: Eucalyptus obliqua L'Hérit., E. fasciculosa F. Muell. and E. leucoxylon F. Muell. Field sites were located in the Mt Lofty Ranges, S.A., near the lower altitudinal limits of the E. obliqua population, where this species begins to be replaced by one or other of the other two. Pairs of trees, one pair of each species, were selected at each site growing within a few metres of each other. Measurements were made in late winter 1977 and during the unusually dry summer of 1977-78. In late winter E. obliqua and E. fasciculosa results were similar. Both had dawn water potential maxima of approximately -0.4 MPa, and stomatal conductance was high throughout the day. By mid summer E. obliqua was suffering water stress. Dawn water potential maxima of -1.93 and -4.35 MPa were measured, and stomatal conductance was low, but not zero, throughout the day. Adjacent E. fasciculosa showed few signs of stress; dawn maximum water potential was -0.7 MPa, and stornatal conductances were high. By late summer both water potentials and stornatal conductances of E. obliqua were much lower than those of adjacent trees of either of the other two species. The significance of these differences is discussed in relation to factors affecting eucalypt distribution patterns.


1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.


Problems when calculating reinforced concrete structures based on the concrete deformation under compression diagram, which is presented both in Russian and foreign regulatory documents on the design of concrete and reinforced concrete structures are considered. The correctness of their compliance for all classes of concrete remains very approximate, especially a significant difference occurs when using Euronorm due to the different shape and sizes of the samples. At present, there are no methodical recommendations for determining the ultimate relative deformations of concrete under axial compression and the construction of curvilinear deformation diagrams, which leads to limited experimental data and, as a result, does not make it possible to enter more detailed ultimate strain values into domestic standards. The results of experimental studies to determine the ultimate relative deformations of concrete under compression for different classes of concrete, which allowed to make analytical dependences for the evaluation of the ultimate relative deformations and description of curvilinear deformation diagrams, are presented. The article discusses various options for using the deformation model to assess the stress-strain state of the structure, it is concluded that it is necessary to use not only the finite values of the ultimate deformations, but also their intermediate values. This requires reliable diagrams "s–e” for all classes of concrete. The difficulties of measuring deformations in concrete subjected to peak load, corresponding to the prismatic strength, as well as main cracks that appeared under conditions of long-term step loading are highlighted. Variants of more accurate measurements are proposed. Development and implementation of the new standard GOST "Concretes. Methods for determination of complete diagrams" on the basis of the developed method for obtaining complete diagrams of concrete deformation under compression for the evaluation of ultimate deformability of concrete under compression are necessary.


2015 ◽  
Vol 72 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Marko Igic ◽  
Nebojsa Krunic ◽  
Ljiljana Aleksov ◽  
Milena Kostic ◽  
Aleksandra Igic ◽  
...  

Background/Aim. The vertical dimension of occlusion is a very important parameter for proper reconstruction of the relationship between the jaws. The literature describes many methods for its finding, from the simple, easily applicable clinically, to quite complicated, with the use of one or more devices for determination. The aim of this study was to examine the possibility of determining the vertical dimension of occlusion using the vocals ?O? and ?E? with the control of values o btained by applying cognitive functions. Methods. This investigation was performed with the two groups of patients. The first group consisted of 50 females and 50 males, aged 18 to 30 years. In this group the distance between the reference points (on top of the nose and chin) was measured in the position of the mandible in the vertical dimension of occlusion, the vertical dimension at rest and the pronunciation of the words ?OLO? and ?ELE?. Checking the correctness of the particular value for the word ?OLO? was also performed by the phonetic method with the application of cognitive exercises when the patients counted from 89 to 80. The obtained difference in the average values i n determining the vertical dimension of occlusion and the ?OLO? and ?ELE? in the first group was used as the reference for determining the vertical dimension of occlusion in the second group of patients. The second group comprised of 31 edentulous persons (14 females and 17 males), aged from 54 to 85 years who had been made a complete denture. Results. The average value obtained for the vertical dimension of rest for the entire sample was 2.16 mm, for the word ?OLO? for the entire sample was 5.51 mm and for the word ?ELE? for the entire sample was 7.47 mm. There was no statistically significant difference between the genders for the value of the vertical dimension at rest, ?ELE? and ?OLO?. There was a statistically significant difference between the values f or the vertical dimension at rest, ?OLO? and ?ELE? for both genders. There was a statistically significant correlation between the value for the vertical dimension at rest, ?OLO? and ?ELE?, for both groups of subjects. Conclusion. Determining the vertical dimension of occlusion requires 5.5 mm subtraction from the position of the mandible in pronunciation of the word ?OLO? or 7.5 mm in pronunciation of the word ?ELE?.


Author(s):  
Nesma M Fahmy ◽  
Adel M Michael

Abstract Background Modern built-in spectrophotometer software supporting mathematical processes provided a solution for increasing selectivity for multicomponent mixtures. Objective Simultaneous spectrophotometric determination of the three naturally occurring antioxidants—rutin(RUT), hesperidin(HES), and ascorbic acid(ASC)—in bulk forms and combined pharmaceutical formulation. Method This was achieved by factorized zero order method (FZM), factorized derivative method (FD1M), and factorized derivative ratio method (FDRM), coupled with spectrum subtraction(SS). Results Mathematical filtration techniques allowed each component to be obtained separately in either its zero, first, or derivative ratio form, allowing the resolution of spectra typical to the pure components present in Vitamin C Forte® tablets. The proposed methods were applied over a concentration range of 2–50, 2–30, and 10–100 µg/mL for RUT, HES, and ASC, respectively. Conclusions Recent methods for the analysis of binary mixtures, FZM and FD1M, were successfully applied for the analysis of ternary mixtures and compared to the novel FDRM. All were revealed to be specific and sensitive with successful application on pharmaceutical formulations. Validation parameters were evaluated in accordance with the International Conference on Harmonization guidelines. Statistical results were satisfactory, revealing no significant difference regarding accuracy and precision. Highlights Factorized methods enabled the resolution of spectra identical to those of pure drugs present in mixtures. Overlapped spectra of ternary mixtures could be resolved by spectrum subtraction coupled FDRM (SS-FDRM) or by successive application of FZM and FD1M.


Author(s):  
Heba M El-Sayed ◽  
Laila E Abdel Fattah ◽  
Hisham E Abdellatef ◽  
Maha A Hegazy ◽  
Mai M Abd El-Aziz

Abstract Background Entecavir (ENT) is an antiretroviral agent prescribed for treatment of HBV and HIV. Objective Development and validation of three simple, sensitive, selective, and precise methods for determination of ENT in presence of its oxidative degradation product (ENT deg.). Methods The first method was based on second derivative (D2) spectrophotometry through measuring the peak amplitude of D2 spectra at 293.6 nm. The second one is mean centering of the ratio spectra (MCR), which allowed measuring the peak amplitude at 280.0 nm. While the third method was HPLC; where ENT was separated from ENT deg. using Zobrax C18column and methanol: water (30:70, v/v), pH 3 as a mobile phase. The three developed methods were validated according to ICH guidelines. Results Linearity range of ENT was 5.00–50.00 μg/mL for both D2and MCR. However, higher sensitivity was achieved using HPLC (1.00–50.00 μg/mL). Accuracy of ENT were 100.60%±0.547, 101.55%±1.2071 and 100.61%±1.207 for D2, MCR and HPLC methods, respectively, and precision was within 1.280. Conclusions The developed methods were successfully applied for the determination of ENT in Tecavir® tablets without interference from ENT deg. They showed no significant difference compared with the official method as well as they could be applied in the quality analysis of ENT with high selectivity, accuracy, and precision. Highlights ENT was quantified using two spectrophotometric (D2 and MCR) methods and an HPLC method in presence of ENT deg. The proposed methods were applied to analysis of ENT tablets with high selectivity, sensitivity, and accuracy.


2021 ◽  
Vol 44 (1) ◽  
pp. 194-202
Author(s):  
Funda Demir ◽  
Meral Yildirim Ozen ◽  
Emek Moroydor Derun

Abstract In this study, essential (Ca, Cr, Cu, Fe, K, Mg, Na, P, Zn), and non-essential (Al, Ni, Pb) element contents of the drinking and baby water samples which are sold in the local market and tap water samples in Istanbul were examined. It was determined that elements of Cr, Cu, Fe, P, Zn, Al, and Ni were below detection limits in all water samples. Among the non-essential elements analyzed in water samples, Pb was the only detected element. At the same time, the percentages that meet the daily element requirements of infants were also calculated. As a result of the evaluations made, there is no significant difference in infant nutrition between baby waters and other drinking waters in terms of the element content.


Healthcare ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 936
Author(s):  
Milan Kojić ◽  
Branka Protić Gava ◽  
Milan Bajin ◽  
Marko Vasiljević ◽  
Jasmina Bašić ◽  
...  

Background: The research objective of the study is to determine the differences in the manifestation of the motor status of normally fed preschool test subjects, classified into groups according to foot status. Methods: This is a simple, comparative observational study. Preschool children included in this study have been subjected to anthropometric measurements in order to determine BMI, tests for motor skills assessment (running at 20 m from a high start, standing broad jump, backwards polygon, rectangular seated forward bend, plate tapping, sit-ups for 60 s, and bent arm hang), and a determination of foot status. The total sample was comprised of 202 test subjects who attended a regular sports program, aged 3.9 to 6.5 years of decimal age (M = 141; Age = 5.3 ± 0.74; Height = 117.3 ± 7.1; Weight = 22 ± 3.7; F = 61; Age = 5.1 ± 0.73; Height = 114.9 ± 7.4; Weight = 21.2 ± 3.8), of which 153 (75.7%) were normally fed, 6 (3%) were undernourished, 30 were overweight (14.9%), and 13 were obese (6.4%). Results: In the total sample, 30 (14.9%) subjects had normal arch feet, 90 (44.6%) high arched feet, and 41 (20.3%) flat feet. We found 41 (20.3%) subjects who had different left and right foot statuses within this sample. The data were processed by means of nonparametric tests (the Kruskal–Wallis and Mann–Whitney U tests) at a significance level p ≤ 0.05. Conclusion: The results show that there is a statistically significant difference between groups of subjects with different foot statuses in the manifestation of motor status in most tests, with a significance level of p ≤ 0.01, and in tests of sit-ups for 60 s and the bent arm hang, there is a statistically significant difference, the level of which is p ≤ 0.05. It is only in the inclination test of rectangular seated forward bend that no statistically significant difference was displayed.


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