Measurement of Fog Oil Penetration into Model Underground Burrow and Hollow Tree Nest Cavities

2007 ◽  
Author(s):  
Mark A. Guelta ◽  
Harold E. Balbach
2005 ◽  
Vol 38 (5) ◽  
pp. 410-415 ◽  
Author(s):  
Maria Hismênia H.M. Garcia ◽  
Lindemberg Souza ◽  
Rita de Cássia M. de Souza ◽  
Alexandre S. Paula ◽  
Érika C. Borges ◽  
...  

Panstrongylus lutzi is generally restricted to the "caatinga" areas of north-eastern Brazil. Adult insects are frequently found in local houses, but colonies have not previously been registered in the statistics of the Control Programme of Chagas Disease. In Ceará State, our study revealed increasing occurrence of this species, usually with high infection rates for Trypanosoma cruzi, and always represented by adults that invaded the artificial environment. We also found nymphs in the peridomicile and inside the houses. In silvatic habitats we collected two adult females from hollow tree trunks, which may represent an alternative natural ecotope for the species in this state. Panstrongylus lutzi entomological collections from Sobral and Crateús, studied by morphology and morphometrics, showed great variability; those from Crateús were larger smaller and paler in colour, with individuals showing genital features consistent with those described for Panstrongylus lutzi or Panstrongylus sherlocki, whereas those from Sobral were darker and with genitalia compatible with P. sherlocki, nevertheless, all were considered to be Panstrongylus lutzi.


The author had already stated, in a former communication to the Royal Society, his having noticed that for several days previous to the settling of a swarm of bees in the cavity of a hollow tree adapted to their reception, a considerable number of these insects were incessantly employed in examining the state of the tree, and particularly of every dead knot above the cavity which appeared likely to admit water. He has since had an opportunity of observing that the bees who performed this task of inspection, instead of being the same individuals as he had formerly supposed, were in fact a continual succession of different bees; the whole number in the course of three days being such as to warrant the inference that not a single labouring bee ever emigrates in a swarm without having seen its proposed future habitation. He finds that the same applies not only to the place of permanent settlement, but also to that where the bees rest temporarily, soon after swarming, in order to collect their numbers. The swarms, which were the subjects of Mr. Knight’s experiments, showed a remarkable disposition to unite under the same queen. On one occasion a swarm, which had arisen from one of his hives, settled upon a bush at a distance of about twenty-five yards; but instead of collecting together into a compact mass, as they usually do, they remained thinly dispersed for nearly half an hour; after which, as if tired of waiting, they singly, one after the other, and not in obedience to any signal, arose and returned home. The next morning a swarm issued from a neighbouring hive, and proceeded to the same bush upon which the other bees had settled on the preceding day; collecting themselves into a mass, as they usually do when their queen is present. In a few minutes afterwards a very large assemblage of bees rushed from the hive from which the former swarm had issued, and proceeded directly to the one which had just settled, and instantly united with them. The author is led from these and other facts to conclude that such unions of swarms are generally, if not always, the result of previous concert and arrangement.


Author(s):  
Kenneth Grahame

The front door of the hollow tree faced eastwards, so Toad was called at an early hour; partly by the bright sunlight streaming in on him, partly by the exceeding coldness of his toes, which made him dream that he was at home in...


2018 ◽  
Vol 24 (1) ◽  
pp. 62
Author(s):  
Nyoman Suaryana ◽  
Iwan Susanto ◽  
Yohannes Ronny ◽  
Ida Rumkita Sembayang

Asbuton is a natural rock asphalt that can be found on the island of Buton in Southeast Sulawesi province, has a large deposits but not yet well utilized. This research aims to find out the performance of asphalt mixtures AC-WC (Asphaltic Concrete Wearing Course) and HRS-WC (Hot Rolled Sheet Wearing Course) using bitumen results from full extraction of asbuton. The research was done by experimental methods through laboratory tests then its performance was compared to convensional mixtures using asphalt oil with penetration grade of 60. The results obtained showed that the bitumen of asbuton did not meet the specification of bitumen based on penetration grade. Characteristics of hot mixture asphalt using bitumen of asbuton showed better performance in terms of the Marshall stability namely 1871 kg higher than the convensional hotmixture of asphalt, with 1100 kg for AC-WC and 1241.9 kg compared with 1094 kg for HRS-WC. In addition, the results of deformation resistance tests showed asphalt mix with pure asbuton  more resistant to rutting shown by higher dynamic stability value namely 4200 track/mm compared with 492 track/mm for AC-WC and 2739 track/mm compared with 325 track/mm. The modulus resilient value of mix with pure asbuton is also higher at temperature of 25°C and relatively the sameat temperatures of 35°C and 45°C. While the resistance of  fatigue for AC-WC and HRS-WC on the test tensile strain of 150 µs were relatively the same as hotmix asphalt using asphalt oil penetration grade of 60, but on test of  a larger tensile strain has worse fatigue resistance, especially for AC-WC.


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