scholarly journals Laboratory studies of homing orientation in the eastern red-spotted newt, Notophthalmus viridescens

1987 ◽  
Vol 131 (1) ◽  
pp. 215-229 ◽  
Author(s):  
J. B. Phillips
Keyword(s):  
Water Temperature ◽  
Laboratory Tests ◽  
Notophthalmus Viridescens ◽  
Magnetic Orientation ◽  
Laboratory Studies ◽  
Navigational System ◽  
South Axis ◽  
Magnetic North ◽  
Migratory Period ◽  
East West

The orientation behaviour of adult male eastern red-spotted newts (Notophthalmus viridescens) was studied in laboratory tests. Newts were collected from ponds located 10–30 km from the laboratory, and housed in water-filled, all-glass aquaria located in a greenhouse or outdoors adjacent to the laboratory building. The aquaria were aligned on the magnetic north-south axis. Newts were tested in a dry, enclosed arena in four magnetic fields: the ambient magnetic field (magnetic north at North) and three altered fields (magnetic north rotated to East, West or South). Newts tested during January-March exhibited weak bimodal magnetic orientation along the axis of the holding tank. However, during the spring migratory period (April until early May), the bimodal response shifted to coincide with the direction of the pond from which the newts had been collected. Much stronger unimodal orientation was elicited by elevating the water temperature to 33–34 degrees C immediately prior to testing. If newts were held in a training tank with an artificial shoreline at one end and exposed to elevation of water temperature after several days of stable water temperatures, they exhibited unimodal shoreward orientation and did not show the seasonal switch to homing behaviour observed in the earlier tests. If, however, the elevation of water temperature followed a period of fluctuating water temperature (over a 20 degrees C range), the newts exhibited strong unimodal orientation in the direction of the pond from which they had been collected. These results suggest that newts possess a navigational system that enables them to home from distances in excess of 20 km. Moreover, these experiments provide the first opportunity to examine the sensory basis of navigational ability in any animal under controlled laboratory conditions.

Results of the experimental bits bench test, equipped with the compound built-up layers

2020 ◽  
pp. 52-56
Author(s):  
V.N. Gadalov ◽  
V. M. Brodsky ◽  
E.A. Filatov ◽  
A.V. Filonovic
Keyword(s):  
Tungsten Carbide ◽  
Laboratory Tests ◽  
Bench Test ◽  
Laboratory Studies ◽  
Induction Method ◽  
Gas Flame ◽  
Flame Method ◽  
Drilling Bit ◽  
Pilot Tests

The article shows the results of performance laboratory studies of compound built-up layers, as well as benches of the pilot tests of the drilling bit rolling cutters, equipped on the bit gage surface of the compound built-up layer; the hardening layers were located along the gage teeth contour. The cast tungsten carbide building-up welding on experimental bits was carried out using a gas-flame method. The induction method of building-up welding was implemented on the rolling cutters of the serial bits. The article shows the results of comparative indicators of serial and experimental bits when their processing on the bench. It was found that experimental bits were more efficient than the serial ones. The estimation of the performance laboratory tests results was confirmed by tests on the bench under pilot conditions of the rolling cutter bits drilling, equipped on the bit gage surface by the compound built-up layer.

LABORATORY TESTS OF DISINFECTANT «MONOCHLORIDE (IODINE CHLORIDE) 2%»

2018 ◽  
Vol 1 (4) ◽  
pp. 27-33
Author(s):  
N. I. Popov ◽  
◽  
A. V. Suvorov ◽  
S. M. Lobanov ◽  
S. A. Michko ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Laboratory Tests ◽  
Consumption Rate ◽  
Laboratory Work ◽  
Laboratory Studies ◽  
E Coli ◽  
Iodine Chloride ◽  
Test Objects ◽  
Test Cultures

The article describes the results of laboratory tests of the effectiveness of the disinfectant Monochloride (Iodine chloride) 2%. Laboratory studies were carried out on test objects and test surfaces contaminated with test cultures of microorganisms, which included museum cultures of E. coli (E. coli 1257), S. aureus 209-P, mycobacteria (pcs. B5), and spores (B. cereus pieces. 96). Disinfection of test objects was carried out by the method of irrigation at a consumption rate of 0,25...0,3 l/ m2 with disinfection of smooth surfaces and 0,5 l/m2, with disinfection of rough surfaces. The treatment was performed twice with an interval of 60 minutes. Our work established that the Monochloride (Iodine chloride) 2% has a high disinfectant activity against Escherichia coli, Staphylococcus aureus, mycobacteria and spores. On the basis of the laboratory work, this tool can be recommended for production tests at veterinary surveillance facilities.

Evaluation of Hydrogen Cracking Susceptibility in X120 Girth Welds

2004 ◽  
Author(s):  
M. L. Macia ◽  
D. P. Fairchild ◽  
J. Y. Koo ◽  
N. V. Bangaru
Keyword(s):  
Laboratory Tests ◽  
High Strength ◽  
Test Method ◽  
Laboratory Studies ◽  
Long Distance ◽  
Hydrogen Cracking ◽  
Girth Welding ◽  
Groove Test ◽  
Girth Welds ◽  
The Cost

To reduce the cost of long distance gas transmission, high strength pipeline steels are being developed. Implementation of high strength pipeline materials requires the avoidance of hydrogen cracking during field girth welding. A study of hydrogen cracking in X120 girth welds has been conducted. Cracking resistance of both the weld metal and heat affected zone (HAZ) were investigated. The laboratory tests included the controlled thermal severity (CTS) test, the WIC test and the Y-groove test. In addition, multi-pass plate welds and full pipe welds were completed and examined for the presence of hydrogen cracks. The suitability of each test method for predicting cracking in X120 girth welds is determined. The morphology of hydrogen cracks in X120 girth welds is described, and the conditions necessary to prevent hydrogen cracking are identified. Following the laboratory studies, construction of X120 pipelines without cracking was demonstrated through a 1.6 km field trial.

scholarly journals Effects of Temperature, Concentration, Age, and Algaecides on Phytophthora capsici Zoospore Infectivity

Plant Disease ◽  
2010 ◽  
Vol 94 (1) ◽  
pp. 54-60 ◽  
Author(s):  
L. L. Granke ◽  
M. K. Hausbeck
Keyword(s):  
Water Temperature ◽  
Irrigation Water ◽  
Phytophthora Capsici ◽  
Growing Season ◽  
Laboratory Studies ◽  
Inoculum Concentration ◽  
Pickling Cucumbers ◽  
Effects Of Temperature ◽  
Water Treatments ◽  
Zoospore Suspension

Controlled laboratory studies were undertaken to determine the effects of water temperature (2, 9, 12, 19, 22, and 32°C), inoculum concentration (1 × 102, 1 × 103, 5 × 103, 1 × 104, 2 × 104, and 4 × 104 zoospores/ml), and zoospore suspension age (0, 1, 3, and 5 days old) on infection of pickling cucumbers (Cucumis sativus) by Phytophthora capsici. Zoospore motility and mortality in response to commercial algaecides were also investigated. Cucumbers became infected at all temperatures tested, except 2°C, and the highest infection incidence was observed for cucumbers incubated in suspensions held at ≥19°C. Fewer fruit (<40% at ≥19°C, 0% at ≤12°C) became infected when water contained 1 × 102 zoospores/ml. Almost 100% of fruit were infected when water contained ≥5 × 103 zoospores/ml at temperatures ≥12°C. While the incidence of fruit infection declined with the zoospore suspension age, infection still occurred when 5-day-old suspensions were used. Commercial algaecides inhibited zoospore motility and caused significant zoospore mortality in laboratory assays, and show promise for treatment of infested irrigation water. Avoidance of infested irrigation water throughout the growing season is warranted until effective and economically acceptable water treatments are developed for field use.

Early history of the Midcontinent Rift inferred from geochemistry and sedimentology of the Mesoproterozoic Osler Group, northwestern Ontario

2007 ◽  
Vol 44 (3) ◽  
pp. 389-412 ◽  
Author(s):  
Pete Hollings ◽  
Philip Fralick ◽  
Brian Cousens
Keyword(s):  
Alluvial Fan ◽  
Midcontinent Rift ◽  
Fluvial Systems ◽  
The North ◽  
Northwestern Ontario ◽  
History Of ◽  
Group A ◽  
South Axis ◽  
Island Basalt ◽  
East West

The Mesoproterozoic 1108–1105 Ma Osler Group, a 3 km thick succession of basaltic flows and sedimentary units on the north shore of Lake Superior, is among the oldest expressions of the Midcontinent Rift. Basal sediments of the Simpson Island Formation (new name) deposited by braided fluvial systems record westward transport of debris eroded from local Archean and Proterozoic rock units. Strata deposited by this fluvial system are intercalated with, and overlain by, ocean-island basalt (OIB)-like basalts, which become increasingly contaminated up section (εNd(1100Ma) = +0.3 to –5.3). The light rare-earth element (LREE) enriched (La/Smn = 1.5–3.9) and heavy REE (HREE) fractionated (Gd/Ybn = 1.5–3.7) subaerial flows are divisible into two units that correlate with other sections of the Osler Group to the east, but simple correlations with more distant sequences are difficult. The volcanic rock dominated portion of the succession is overlain by a thin (25 m thick) conglomerate–sandstone assemblage representing southeast progradation of an alluvial fan in a semi-arid climatic setting. Clast lithologies and geochemistry indicate no extra-rift detritus was delivered from the hinterland of the fan. Various lines of evidence in both volcanic and sedimentary rocks support a scenario where early, pre-1108 Ma, subsidence along a north–south axis from the western arm of the rift to the Nipigon Embayment was replaced by subsidence along the east–west rift axis between 1108 and 1105 Ma.

scholarly journals Laboratory studies of the flow rates of debris-laden ice

2003 ◽  
Vol 37 ◽  
pp. 108-112 ◽  
Author(s):  
Tim H. Jacka ◽  
Shavawn Donoghue ◽  
Jun Li ◽  
William F. Budd ◽  
Ross M. Anderson
Keyword(s):  
Laboratory Tests ◽  
Ice Sheets ◽  
Ice Sheet ◽  
Laboratory Studies ◽  
Polar Ice ◽  
Flow Rates ◽  
Basal Ice ◽  
Ice Flows ◽  
Polar Ice Sheets ◽  
Deformation Tests

AbstractIce-sheet basal ice is warmer than that above because of the heat from the Earth’s interior. The stresses acting on the basal ice are greatest. In addition, the basal ice often contains debris consisting of silt and small stones picked up from the rock over which the ice flows. Because the base is the warmest part of an ice sheet and the stress there is greatest, flow rates in the basal ice are large and often contribute most of the ice movement. It is therefore important, for accurate modelling of the ice sheets, to know whether the debris within the basal ice enhances or retards the flow of the ice. In this paper, we describe laboratory deformation tests in uniaxial compression and in simple shear, on sand-laden ice. We find no significant dependence of flow rate on sand content (up to 15% volume) in the stress range 0.13–0.5 MPa and temperature range –0.02 to –18.0°C. Further work needs to include laboratory tests on debris-laden ice extracted from the polar ice sheets. This work is underway.

Laboratory Studies on the Food of Some Coccinellids (Coleoptera) Found in Ontario Peach Orchards

1957 ◽  
Vol 89 (12) ◽  
pp. 572-579 ◽  
Author(s):  
Wm. L. Putman
Keyword(s):  
Biological Control ◽  
Food Habits ◽  
Laboratory Tests ◽  
Economic Importance ◽  
Laboratory Studies ◽  
Present Account ◽  
Stethorus Punctillum

Food habits and occurrence of the commoner species of coccinellids in peach orchards of the Niagara Peninsula, Ontario, are being investigated in connection with a study of the effects of pesticides on biological control agencies. Results of a study of Stethorus punctillum Weise have already been published (Putman, 1955). The present account deals with laboratory tests of feeding, mostly during June and July from 1952 to 1955, with prey of special economic importance in peach orchards.

LABORATORY RESEARCH RESULTS OF ONION SEPARATION ON A BAR ELEVATOR WITH AN ADJUSTABLE TILT ANGLE

2020 ◽  
Keyword(s):  
Quality Indicators ◽  
Laboratory Tests ◽  
Separation Process ◽  
Laboratory Research ◽  
Laboratory Studies ◽  
Blade Angle ◽  
Quality Performance ◽  
Root Crops ◽  
Optimal Values ◽  
Translational Speed

Existing machines for harvesting root crops and onions do not provide qualitative indicators of root crops pile separation, which leads to a violation of agrotechnical requirements when harvesting them [1, 2]. It is necessary to search for new solutions to increase the quality indicators of root crop separation, namely to increase the completeness of separation and reduce damage. The article presents the design of the onion set harvesting machine, equipped with a bar elevator with an asymmetric arrangement of shakers. We described the methodology and results of laboratory studies to determine the quality indicators of heap onion sets separation on an experimental bar elevator. The results of laboratory tests of the onion set harvesting machine equipped with a bar elevator with an adjustable blade angle showed a high-quality performance of separation process at optimal values of parameters: translational speed of the bar elevator blade vEL = 1.55 ... 1.68 m s, the supply of onions heap Qb?- 19.7 ... 27.1 kg s and inclination angle of the blade bar elevator is in the range аг= 15.1... 21.9 degrees. The use of a bar elevator with an adjustable angle of inclination of the blade allows to increase the completeness of onion sets separation by 20%, and reduce damage to the bulbs by 11%.

Guillain-Barré Syndrome in Children

1986 ◽  
Vol 8 (3) ◽  
pp. 69-74
Author(s):  
Owen B. Evans
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Laboratory Tests ◽  
Routine Laboratory ◽  
Laboratory Studies ◽  
Intensive Care Therapy ◽  
Autoimmune Attack ◽  
Peripheral Nervous System Myelin ◽  
Progressive Weakness ◽  
Careful History

The Guillain-Barré syndrome is an acquired, monophasic illness of the peripheral nervous system. The etiology is an autoimmune attack directed against peripheral nervous system myelin, although the exact mechanism of the immunologic injury is unknown. The major clinical features are rapidly progressive weakness and hyporeflexia, and the most serious complications during the acute phase of the disease are respiratory failure and autonomic cardiovascular disturbances. A careful history, physical examination, and routine laboratory tests are necessary to make a clinical diagnosis and to exclude other disorders that cause acute weakness. Results of laboratory studies that aid in the diagnosis, CSF protein and electrodiagnostic studies, are usually normal during the first week of the illness. The prognosis for children with Guillian-Barré syndrome is excellent for full recovery using modern intensive care therapy for respiratory support and management of other complications.

An assessment of leaf-litter and epigaeic ants (Hymenoptera: Formicidae) living in different landscapes of the Atlantic Forest Biome in the State of Bahia, Brazil

2017 ◽  
Vol 5 (19) ◽  
pp. 1 ◽  
Author(s):  
Roberta De Jesus Santos ◽  
Elmo Borges Azevedo Koch ◽  
Clarissa Machado Pinto Leite ◽  
Tiago Jordão Porto ◽  
Jacques Hubert Charles Delabie
Keyword(s):  
Leaf Litter ◽  
Atlantic Forest ◽  
The State ◽  
Brazilian Atlantic Forest ◽  
The North ◽  
Forest Remnants ◽  
Axis Parallel ◽  
Leaf Litter Ants ◽  
South Axis ◽  
East West

The Brazilian Atlantic Forest has a rich biodiversity increasingly threatened by human activities. Since the colonial period, the coast of the state of Bahia is among the most affected regions of Brazil by anthropic pressure. Bahia encloses Atlantic Forest remnants distributed in an area reaching 100-200 km along the east-west axis, by 1,000 km along the north-south axis, parallel to the coast of the Atlantic Ocean. We report hereafter the results of an intensive field survey of leaf litter and epigaeic ants realized in forest remnants of the Atlantic Forest landscapes within the original extension of the biome in 11 localities distributed along four degrees of latitude in the state of Bahia. In each site, 16 plots were collected using pitfall and eight using Winkler traps. We identified 391 ant species belonging to 71 genera and nine subfamilies. Among all species recorded, 21 were common to the whole 11 localities, while 98 species were recorded in a single locality. This study highlights the richness and diversity of epigaeic and leaf-litter ants living in the northern part of the Brazilian Atlantic Forest, and is one of the most representative soil ants’ inventories ever done in this biome for a single state of Brazil.

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