scholarly journals Spacing effect on growth and yeld of fast rotation Eucalyptus at 24 months of age

2020 ◽  
Vol 9 (6) ◽  
pp. e49963404
Author(s):  
Ana Paula Mezoni Correa ◽  
Ana Paula Leite de Lima ◽  
Sebastião Ferreira de Lima ◽  
Wesley Gomes da Silva ◽  
Lorena Stolle ◽  
...  

The objective of this study was to evaluate the growth in height, diameter and volume production of a eucalyptus clone at 24 months of age planted at different spacing. Values of circumference at soil height, circumference at chest height and the heights of all plants in the plots were collected at 6, 12, 18 and 24 months after planting. Using the collected data, the diameter values at ground and chest height and the mean height at each age were calculated. Rigorous cubing of the average tree in each plot was performed 24 months after planting to obtain the wood volume per tree and per hectare. The spacing did not present a clear pattern of influence on the total height of the plants. The final height was not affected by spacing. The effect of planting spacing on growth in diameter at soil height intensified from the first year after planting. Tree mean diameter increased with planting spacing, as well as the wood volume per tree. Wood volume per hectare was higher in the denser spacing.

1986 ◽  
Vol 113 (4_Suppl) ◽  
pp. S157-S163 ◽  
Author(s):  
K.W. KASTRUP ◽  
_ _

Abstract Early therapy with a low dose of estrogen (estradiol-17β) was given to 33 girls with Turner's syndrome (T.s.) for a period of 4 years. The dose (0.25-2 mg/day) was adjusted every 3 months to maintain plasma estradiol in the normal concentration range for bone age. Growth velocity was compared with that of untreated girls with T.s. All girls were above age 10 years. Bone age was below 10 years in 11 girls (group I) and above 10 years in 22 girls (group II). Growth velocity in the first year of treatment in group I 7.5 ± 1.3 cm (SD) with mean SD score (SDS) of +4.3 and in group II 4.9 ± 1.3 with mean SDS of +3.5. Growth velocity decreased in the following years to 1.6 ± 1.0 cm, SDS -1.44 in group I and 0.9 ± 0.6cm, SDS -2.34 in group II during the fourth year. Withdrawal bleeding occurred in 16 girls of group II after the mean of 23 (range 15-33) months and in 3 girls of group I after 15 to 51 months of treatment. The treatment did not cause an inappropriate acceleration of pubertal development. Breast development appeared in most girls by 3 months of treatment. Pubic hair appeared by 12 months of treatment in group I; it was present in most girls in group II at start of treatment. Final height is known for 12 girls of group II; it was 144.2 ± 4.5 cm. The final height as predicted at the start of therapy was 142.2 ± 5.3 cm. Bone age advanced in the first year of treatment by 2 years. Early treatment with small doses of estrogens induces a growth spurt and normalizes the events of puberty. This will presumably decrease the psychological risks associated with abnormally delayed development.


2018 ◽  
Vol 116 (1) ◽  
pp. 110
Author(s):  
Lixiong Shao ◽  
Jiang Diao ◽  
Wang Zhou ◽  
Tao Zhang ◽  
Bing Xie

The growth behaviour of spinel crystals in vanadium slag with high Cr2O3 content was investigated and clarified by statistical analyses based on the Crystal Size Distribution (CSD) theory. The results indicate that low cooling rate and Cr2O3 content benefit the growth of spinel crystals. The chromium spinel crystals firstly precipitated and then acted as the heterogeneous nuclei of vanadium and titanium spinel crystals. The growth mechanisms of the spinel crystals at the cooling rate of 5 K/min consist two regimes: firstly, nucleation control in the temperature range of 1873 to 1773 K, in which the shapes of CSD curves are asymptotic; secondly, surface and supply control within the temperature range of 1773 to 1473 K, in which the shapes of CSD curves are lognormal. The mean diameter of spinel crystals increases from 3.97 to 52.21 µm with the decrease of temperature from 1873 to 1473 K.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Marziyeh Rajabi ◽  
Afshin Ostovar ◽  
Ali Akbari Sari ◽  
Sayed Mahmoud Sajjadi-Jazi ◽  
Noushin Fahimfar ◽  
...  

Abstract Background Osteoporotic fractures impose significant costs on society. The objective of this study was to estimate the direct costs of the hip, vertebral, and forearm fractures in the first year after fracture incidence in Iran. Methods We surveyed a sample of 300 patients aged over 50 years with osteoporotic fractures (hip, vertebral, and forearm) admitted to four hospitals affiliated to Tehran University of Medical Sciences, Iran, during 2017 and were alive six months after the fracture. Inpatient cost data were obtained from the hospital patient records. Using a questionnaire, the data regarding outpatient costs were collected through a phone interview with patients at least six months after the fracture incidence. Direct medical and non-medical costs were estimated from a societal perspective. All costs were converted to the US dollar using the average exchange rate in 2017 (1USD = IRR 34,214) Results The mean ± standard deviation (SD) age of the patient was 69.83 ± 11.25 years, and 68% were female. One hundred and seventeen (39%) patients had hip fractures, 56 (18.67%) patients had vertebral fractures, and 127 (42.33%) ones had forearm fractures. The mean direct cost (medical and non-medical) during the year after hip, vertebral and forearm fractures were estimated at USD5,381, USD2,981, and USD1,209, respectively. Conclusion The direct cost of osteoporotic fracture in Iran is high. Our findings might be useful for the economic evaluation of preventive and treatment interventions for osteoporotic fractures as well as estimating the economic burden of osteoporotic fractures in Iran.


Author(s):  
Ferréol Berendt ◽  
Erik Pegel ◽  
Lubomir Blasko ◽  
Tobias Cremer

AbstractBark characteristics are not only used in the forest-wood supply chain, for example to calculate standing volumes, but also to transform wood volumes and masses. In this study, bark thickness, bark volume and bark mass were analyzed on the basis of 150 Scots pine discs, with a mean diameter of 13 cm. The mean double bark thickness was 3.02 mm, the mean bark volume proportion was 5.6% and mean bark mass proportion was 3.3%. Bark proportions were significantly affected by the log-specific variables ‘diameter over bark’, ‘proportion of bark damage’ and ‘double bark thickness’.


1971 ◽  
Vol 16 (3) ◽  
pp. 173-182 ◽  
Author(s):  
Gavin Shaw ◽  
Bernard Groden ◽  
Evelyn Hastings

The establishment, staffing and structure and observations made in the first year of the existence of coronary care in an intensive care unit in a general hospital are recorded. Two hundred and twenty eight patients were admitted during the year in whom the diagnosis of myocardial infarction was confirmed. There were 29 deaths in the unit and 14 deaths occurred in the wards of the hospital after discharge from the unit. 49.1 per cent of the patients were admitted within 4 hours of the onset of symptoms and the mean duration of stay in the unit was 86.5 hours. The type of arrhythmia detected in the unit, and the treatment given to the patients both before and after admission to the intensive care unit are described.


2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Rahim Foroughbakhch ◽  
Artemio Carrillo Parra ◽  
Jorge Luis Hernández Piñero ◽  
Marco Antonio Alvarado Vázquez ◽  
Alejandra Rocha Estrada ◽  
...  

A research strategy was established to analyze the structure of timber trees in terms of forest productivity (volume and wood density) of 10 species. The native speciesAcacia farnesiana, Acacia schaffneri,Bumelia celastrina,Cercidium macrun,Condalia hookeri,Ebenopsis ebano,Helietta parvifolia, andProsopis laevigataand the exotic speciesEucalyptus camaldulensisandLeucaena leucocephalawere chosen due to their ecological and economic importance to the rural villages of northeastern Mexico. Measurements of different growth parameters and volume of trees were evaluated. The introduced speciesE. camaldulensisandL. leucocephalashowed the best performance in wood volume production per tree and per hectare when compared to the native species. Likewise, among the native species,E. ebano,P. laevigata,C. hookeri, andA. farnesianatended to show better characteristics in terms of wood volume production in comparison toH. parvifolia,A. schaffneri,C. macrum, andB. celastrina. Results showed a high diversity on the properties studied. The high biomass produced by most of the species considered in this study revealed their great energetic potential when used as wood and firewood or vegetal charcoal.


NANO ◽  
2012 ◽  
Vol 07 (06) ◽  
pp. 1250045 ◽  
Author(s):  
YUN SUN ◽  
RYO KITAURA ◽  
TAKUYA NAKAYAMA ◽  
YASUMITSU MIYATA ◽  
HISANORI SHINOHARA

The influences of synthesis parameters on the mean diameter and diameter distribution of as-grown single-wall carbon nanotubes (SWCNTs) with chemical vapor deposition (CVD) using the mist flow method have been investigated in detail with Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We found that CVD reaction temperature and flow rate play an essential role in controlling the mean diameter and the quality of as-grown SWCNTs. Furthermore, we found that the carbon supply kinetics can be a dominant factor to determine the diameter of as-grown SWCNTs in the present mist flow method. Under a different combination of various parameters, the mean diameter of SWCNTs can be varied from 0.9 nm to 1.5 nm controllably.


2003 ◽  
Vol 10 (5) ◽  
pp. 987-993 ◽  
Author(s):  
Thomas Zeller ◽  
Ulrich Frank ◽  
Karlheinz Bürgelin ◽  
Uwe Schwarzwälder ◽  
Peter-Christian Flügel ◽  
...  

Purpose: To evaluate the efficacy and safety of a new atherectomy device for the treatment of infragenicular lesions in arteries with a reference diameter of at least 2.5 mm. Methods: Twenty-seven below-the-knee lesions in 17 patients (12 men; mean age 69±12 years) with chronic peripheral arterial occlusive disease were treated with directional atherectomy. The target lesion was in the popliteal artery (segment 3) in 2 (7%) cases, the tibioperoneal trunk in 12 (44%), the peroneal artery in 8 (30%), the anterior tibial artery in 2 (7%), and the posterior tibial artery in 3 (11%). Six (22%) of the lesions were in-stent stenoses. The mean diameter stenosis was 87%±9%, and the mean lesion length was 34±24 mm. Results: All but 2 (7%) of the lesions could be treated successfully (residual stenosis <30%) with the atherectomy catheter (93% technical success) using an average of 5±2 (range 1–10) passes of the device. Six lesions (22%) were treated after predilation and 21 (78%) with primary atherectomy. In 8 (30%) lesions, additional balloon angioplasty was performed. The 2 failures were in heavily calcified lesions through which the device could not pass despite predilation. The mean diameter stenosis after atherectomy was 14%±22% (range 0%–90%); after additional balloon angioplasty, the mean residual stenoses reduced to 12%±21% (range 0%–100%). One (6%) of the 2 patients who failed atherectomy sustained a thrombotic occlusion of the target vessel. This complication was treated successfully with local lysis, but the vessel reoccluded 3 days later; a stent was implanted. The mean ankle-brachial index increased from 0.50±0.27 to 0.86±0.40 before discharge. Conclusions: Below-the-knee native vessel lesions and in-stent restenoses with a diameter of at least 2.5 mm can be treated successfully and safely with this new atherectomy catheter. Additional balloon angioplasty was necessary in only a few cases.


1976 ◽  
Vol 98 (2) ◽  
pp. 297-302 ◽  
Author(s):  
K. G. T. Hollands ◽  
K. C. Goel

The general concept of the mean diameter of the disperse phase of an aerosol system, first introduced by Mugele and Evans in 1951, has proven to be a very useful one. In this concept, the proper mean diameter, xp,q, is characterized by a single pair of indices, p and q, which are dependent on the actual type of aerosol system under consideration. This paper re-examines the validity of this concept of mean diameter in heat and mass transfer aerosol systems. The concept is found to be applicable only under a very narrow range of conditions. Attention is then given to a more general definition of a mean diameter, applicable to aerosol heat or mass exchangers. Analyses of these devices shows that the more general mean diameter is a function of the capacity rate ratio, R, and effectiveness of the heat exchanger, ε. Solutions to the governing equations have permitted the mean diameter to be presented graphically as a function of these variables. These solutions are given for two types of particle size distributions, the Rosin-Rammler and the log-probability, and for both parallel-flow and counter-flow heat exchangers. The solutions are, however, restricted to cases where the resistance to heat or mass transfer lies exclusively in the continuous phase.


1957 ◽  
Vol 35 (4) ◽  
pp. 527-572 ◽  
Author(s):  
G. H. Duff ◽  
Norah J. Nolan

Two measures are needed to describe numerically the activity of the internodal cambium in terms of annual increment. These are "specific wood volume increment", a measure of additive growth and "specific increment of cambial area", a measure of multiplicative growth. The mean area of the internodal cambium is the basis of reference for both since it is the measure of that which is active in growth. The former measure of specific growth is numerically equal to ring width and the manner of its factorial control has already been considered. Data for the latter are new.The geometry of the apical meristem and its products is too complex for the ready computation of specific terminal growth, but it can be shown empirically that internode length is a valid measure of apical activity. Analysis of internodal wood volume growth into its three linear components leads to the conclusion that the determinants in control of wood growth act mainly through their effect upon apical activity and upon specific increment of cambial area.


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