LOW TEMPERATURE INJURY TO ROOTS OF WHITE ELM

1957 ◽  
Vol 33 (2) ◽  
pp. 156-163 ◽  
Author(s):  
H. H. V. Hord ◽  
H. Van Groenewoud ◽  
C. G. Riley
Keyword(s):  
Growth Rate ◽  
Low Temperature ◽  
Cold Weather ◽  
Ulmus Americana ◽  
Ecological Conditions ◽  
Winter Temperatures ◽  
Introduced Trees ◽  
Climatic Records

White elms (Ulmus americana L.) failed to leaf properly at Saskatoon, Saskatchewan, in the spring of 1950 following unusually cold weather in January. Although precipitation in 1949 and the first six months of 1950 was well above average, the symptoms were characteristic of moisture deficiency. Trees on cultivated ground and trees whose growth rate was below average suffered most. On the basis of symptoms, climatic records, and ecological conditions it is concluded that the above-ground symptoms were a result of the killing of roots by unusually low winter temperatures. The occurrence of this injury provides a good example of difficulties that may be encountered when introduced trees are not completely adapted to the environment.

ФОРМИРОВАНИЕ ПЕРЕХОДНОГО СЛОЯ ALN НА ТЕМПЛЕЙТАХ 3С-SIC/SI(111) МЕТОДОМ АММИАЧНОЙ МОЛЕКУЛЯРНО-ЛУЧЕВОЙ ЭПИТАКСИИ

2020 ◽  
Vol 96 (3s) ◽  
pp. 148-153
Author(s):  
С.Д. Федотов ◽  
А.В. Бабаев ◽  
В.Н. Стаценко ◽  
К.А. Царик ◽  
В.К. Неволин
Keyword(s):  
Crystal Structure ◽  
Growth Rate ◽  
Low Temperature ◽  
Surface Morphology ◽  
Single Crystal ◽  
Root Mean Square Roughness ◽  
Rate Variation ◽  
Mean Square ◽  
Nucleation Layer ◽  
Low Temperature Epitaxy

Представлены результаты изучения морфологии поверхности и структуры слоев AlN, сформированных аммиачной МЛЭ на темплейтах 3C-SiC/Si(111) on-axis- и 4° off-axis-разориентации. Опробован технологический режим низкотемпературной эпитаксии зародышевого слоя AlN на поверхности 3C-SiC(111). Среднеквадратичная шероховатость поверхности (5 х 5 мкм) слоев AlN толщиной 150 ± 50 нм составила 2,5-3,5 нм на темплейтах 3C-SiC/Si(111) on-axis и 3,3-3,5 нм на 4° off-axis. Показано уменьшение шероховатости смачивающего слоя AlN при изменении скорости роста. Получены монокристаллические слои AlN(0002) со значениями FWHM (ω-геометрия) 1,4-1,6°. The paper presents the surface morphology and crystal structure of AlN layers formed by ammonia MBE on 3C-SiC/Si(111) on-axis and 4° off-axis disorientation. It offers the technological approach of low-temperature epitaxy of the AlN nucleation layer on the 3C-SiC (111) surface. Root mean square roughness (5 х 5 |xm) of AlN layers with thickness of 150 ± 50 nm was 2,5-3,5 nm onto on-axis templates and 3.3-3.5 nm onto 4° off-axis. It appears that the RMS roughness of the AlN surface is changing with the growth rate variation. Single-crystal AlN(0002) layers with FWHM values (ω-geometry) of 1.4-1.6° have been obtained.

scholarly journals Reconstructing Late Pleistocene paleoclimate at the scale of human behavior: an example from the Neandertal occupation of La Ferrassie (France)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarah Pederzani ◽  
Vera Aldeias ◽  
Harold L. Dibble ◽  
Paul Goldberg ◽  
Jean-Jacques Hublin ◽  
...  
Keyword(s):  
Human Behavior ◽  
Late Pleistocene ◽  
Tooth Enamel ◽  
Climatic Conditions ◽  
Climatic Data ◽  
Human Scale ◽  
Winter Temperatures ◽  
Archaeological Materials ◽  
Climatic Records

AbstractExploring the role of changing climates in human evolution is currently impeded by a scarcity of climatic information at the same temporal scale as the human behaviors documented in archaeological sites. This is mainly caused by high uncertainties in the chronometric dates used to correlate long-term climatic records with archaeological deposits. One solution is to generate climatic data directly from archaeological materials representing human behavior. Here we use oxygen isotope measurements of Bos/Bison tooth enamel to reconstruct summer and winter temperatures in the Late Pleistocene when Neandertals were using the site of La Ferrassie. Our results indicate that, despite the generally cold conditions of the broader period and despite direct evidence for cold features in certain sediments at the site, Neandertals used the site predominantly when climatic conditions were mild, similar to conditions in modern day France. We suggest that due to millennial scale climate variability, the periods of human activity and their climatic characteristics may not be representative of average conditions inferred from chronological correlations with long-term climatic records. These results highlight the importance of using direct routes, such as the high-resolution archives in tooth enamel from anthropogenically accumulated faunal assemblages, to establish climatic conditions at a human scale.

scholarly journals Age and growth of the white croaker Micropogonias furnieri (Perciformes: Sciaenidae) in a coastal area of Southeastern Brazilian Bight

2017 ◽  
Vol 15 (1) ◽  
Author(s):  
Rosa S. Santos ◽  
Marcus R. da Costa ◽  
Francisco G. Araújo
Keyword(s):  
Growth Rate ◽  
Low Temperature ◽  
Growth Parameters ◽  
Direct Application ◽  
Age And Growth ◽  
Fish Populations ◽  
Edge Type ◽  
White Croaker ◽  
Micropogonias Furnieri ◽  
Available Information

ABSTRACT Studies on age and growth of fish populations have direct application in fisheries and contribute for policies of conservation. Our aim was update information on the Micropogonias furnieri growth parameters based on sagittae otoliths annulis readings, and we expected that the studied population from Southeast Brazil can reach more longevity than the reported in the available literature. We examined 286 individuals between August-2010 and July-2011 from Ubatuba Bay, SP. The Total Length ranged 200-480 mm. The determined growth parameters were: Males, L∞ =523.4mm, k = 0.05×year-1, t0 = -8.78 year; Females L∞ = 573.5mm, k = 0.06 × year-1, t0 = -7.49 year. The MI and % of edge type evidenced the formation of one ring per year during autumn/winter, coinciding with low temperature and low growth rate. These results differed from those reported for the Vazzoler’s Population I (summer), and we detected higher longevity (45-48 years) as compared with the recorded in the available information.

scholarly journals Low temperature mixed-mode debond fracture and fatigue characterisation of foam core sandwich

2018 ◽  
Vol 22 (4) ◽  
pp. 1039-1054 ◽  
Author(s):  
Arash Farshidi ◽  
Christian Berggreen ◽  
Leif A Carlsson
Keyword(s):  
Fracture Toughness ◽  
Growth Rate ◽  
Low Temperature ◽  
Mixed Mode ◽  
Room Temperature ◽  
Sliding Mode ◽  
Fatigue Tests ◽  
Mode I ◽  
Foam Core ◽  
Climatic Chamber

This paper experimentally investigates the effects of low temperature on fracture toughness and fatigue debond growth rate in foam core sandwich composites. Mixed-mode bending specimens were statically and cyclically tested inside a climatic chamber at a low temperature (−20°C) and at room temperature (23°C) as a reference. Testing was conducted in mode I (opening) and mixed-mode I/II (opening-sliding) mode mixities. The fatigue tests results are presented according to the modified Paris–Erdogan relation. Results showed substantial fracture toughness reduction due to low temperature. Low temperature furthermore elevated the cyclic crack growth rate.

scholarly journals High growth rate hydride vapor phase epitaxy at low temperature through use of uncracked hydrides

2018 ◽  
Vol 112 (4) ◽  
pp. 042101 ◽  
Author(s):  
Kevin L. Schulte ◽  
Anna Braun ◽  
John Simon ◽  
Aaron J. Ptak
Keyword(s):  
Growth Rate ◽  
Low Temperature ◽  
Vapor Phase ◽  
High Growth ◽  
High Growth Rate ◽  
Vapor Phase Epitaxy ◽  
Hydride Vapor Phase Epitaxy

scholarly journals Different Transcriptional Responses from Slow and Fast Growth Rate Strains of Listeria monocytogenes Adapted to Low Temperature

2016 ◽  
Vol 7 ◽  
Author(s):  
Ninoska Cordero ◽  
Felipe Maza ◽  
Helen Navea-Perez ◽  
Andrés Aravena ◽  
Bárbara Marquez-Fontt ◽  
...  
Keyword(s):  
Growth Rate ◽  
Listeria Monocytogenes ◽  
Low Temperature ◽  
Fast Growth ◽  
Transcriptional Responses ◽  
Fast Growth Rate
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