scholarly journals Some Observations on Glacier Flow

1951 ◽  
Vol 1 (9) ◽  
pp. 496-500 ◽  
Author(s):  
R. Haefeli

AbstractThe excavation of a tunnel by I’Energie Ouest Suisse (EOS) presented inter alia the opportunity to construct a longitudinal profile of the glacier speed and also to observe the speed of the transverse contraction of a circular section. The swift change of shape without fracture was noteworthy. A second tunnel driven from the glacier snout straight up the subglacial stream gave the opportunity to establish a definite connection between the form of the glacier sole and its surface. Finally, measurements of the glacier speeds on the surface and their variations from year to year gave a closer indication of the nature of Forbes’s bands.

1951 ◽  
Vol 1 (09) ◽  
pp. 496-500 ◽  
Author(s):  
R. Haefeli

Abstract The excavation of a tunnel by I’Energie Ouest Suisse (EOS) presented inter alia the opportunity to construct a longitudinal profile of the glacier speed and also to observe the speed of the transverse contraction of a circular section. The swift change of shape without fracture was noteworthy. A second tunnel driven from the glacier snout straight up the subglacial stream gave the opportunity to establish a definite connection between the form of the glacier sole and its surface. Finally, measurements of the glacier speeds on the surface and their variations from year to year gave a closer indication of the nature of Forbes’s bands.


Author(s):  
Gilberto Gonçalves Facco ◽  
Eloty Justina Schleder ◽  
Natalia Yoshioka de Vidis ◽  
Maristela Halverson ◽  
Rosemary Matias ◽  
...  

This study aimed to carry out morphoanatomical, histochemical and phytochemical analysis of leaves and stems of Tetrapterys multiglandulosa Cav. (Malpighiaceae), a native plant responsible for abortion and sudden death in beef cattle. Plant specimens underwent anatomical study, in which leaves and stems were dried and ground with aqueous and ethanol extracts subjected to histochemical and phytochemical analysis. Anatomical observation of vegetative organs detected the presence of simple columnar cells in the adaxial epidermis, palisade mesophyll, parenchyma with a layer of cells and paracitic type stomata. Stem cross-sections presented circular section, single layer (uniseriate) epidermis with thick cuticle and Malpighi’s trichomes, the phelogen was in differentiation. The cortex showed angular collenchyma, parenchyma with exogenous channels and druse shaped calcium oxalate crystals. Phytochemical tests of aqueous and ethanol extracts of leaves and stems indicated the presence of phenolic compounds, tannins, flavonoids, saponins, alkaloids and cardiotonic heterosides. Potentially phytotoxic secondary metabolites evidenced in the leaves and stems, including saponins and cardiotonic heterosides were correlated with clinical signs observed in intoxicated animals.


Parasitology ◽  
1928 ◽  
Vol 20 (1) ◽  
pp. 113-114 ◽  
Author(s):  
W. Rees Wright

Whilst studying the development of Fasciola hepatica, I observed that the “collar” of the redia was rarely so prominent as it was figured and described by Thomas (1883). This observation, and a consideration of the mechanical requirements of the case, led me to suggest (1927) that Thomas was incorrect when he attributed to this structure the function of maintaining the circular section of the redia.


2019 ◽  
Vol 13 ◽  
pp. 04020
Author(s):  
Giovan Battista Mattii ◽  
Eleonora Cataldo ◽  
Linda Salvi ◽  
Sofia Sbraci ◽  
Francesca Paoli ◽  
...  

In the early stages of planting, the shelter can provide for young vines protection against damage of various kinds. Despite their widespread use, few surveys have been devoted to the study of innovative shelter types and the possible influence of these protections on the physiology and development of plants. In the present experiment, which took place in 2017 in a Tuscan winery, the effects of vine protections by the company OSO (Prato) on single leaf gas exchanges and on the shoot growth in the first year of planting were studied. Three types of shelters with a circular section (completely perforated, partially perforated and closed) have been compared with the traditional full-wall shelters with square section. During the growing season, sprout growth measures, leaf area, leaf gas exchanges and water potential were carried out on the young vines. At the end of the season, shoots were sampled to measure the dry matter accumulated during the season. Among the shelters taken into consideration, it emerges that the completely perforated type guarantees the best development, with differences that are almost always significant for most of the measured parameters with traditional shelters. On the contrary, the closed typology has led to a reduction in growth, in gas exchanges and in water potential. In conclusion, the type completely perforated could constitute a valid alternative to the traditional one because, besides being a useful means for the protection of the vine, it could benefit the development of the root system in the early stages of growth.


2012 ◽  
Vol 53 (60) ◽  
pp. 257-266 ◽  
Author(s):  
E. Rignot ◽  
I. Fenty ◽  
D. Menemenlis ◽  
Y. Xu

AbstractWe examine the pattern of spreading of warm subtropical-origin waters around Greenland for the years 1992–2009 using a high-resolution (4km horizontal grid) coupled ocean and sea-ice simulation. The simulation, provided by the Estimating the Circulation and Climate of the Ocean, Phase II (ECCO2) project, qualitatively reproduces the observed warming of subsurface waters in the subpolar gyre associated with changes of the North Atlantic atmospheric state that occurred in the mid-1990s. The modeled subsurface ocean temperature warmed by 1.5˚C in southeast and southwest Greenland during 1994–2005 and subsequently cooled by 0.5˚C; modeled subsurface ocean temperature increased by 2–2.5˚C in central and then northwest Greenland during 1997–2005 and stabilized thereafter, while it increased after 2005 by <0.5˚C in north Greenland. Comparisons with in situ measurements off the continental shelf in the Labrador and Irminger Seas indicate that the model initial conditions were 0.4˚C too warm in the south but the simulated warming is correctly reproduced; while measurements from eastern Baffin Bay reveal that the model initial conditions were 1.0˚C too cold in the northwest but the simulated ocean warming brought modeled temperature closer to observations, i.e. the simulated warming is 1.0˚C too large. At several key locations, the modeled oceanic changes off the shelf and below the seasonal mixed layer were rapidly transmitted to the shelf within troughs towards (model-unresolved) fjords. Unless blocked in the fjords by shallow sills, these warm subsurface waters had potential to propagate down the fjords and melt the glacier fronts. Based on model sensitivity simulations from an independent study (Xu and others, 2012), we show that the oceanic changes have very likely increased the subaqueous melt rates of the glacier fronts, and in turn impacted the rates of glacier flow.


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