Staircase test

Studies on the cognitive effects of areca are scarce, but its known cholinergic mechansims have led some researchers to formally investigate the effects. Arecoline improves memory on a staircase test in rats, but effects were dose dependent (Molinengo et al. 1995). A low dose (0.5 mg/kg) improves performance, but a large dose (3.5-8 mg/kg) causes impair-... 

The sedative and anxiolytic effects of passionflower were examined in two other animal behavioral assays (staircase test, light/dark box choice test). Both anxiolytic and sedative effects occur, as well as potentiation... 

Abrous DN, Dunnett SB (1994) Skilled paw reaching in rats the staircase test. Neurosci Prof 5 1-11. 

Whishaw IQ, Woodward NC, Miklyaeva E, Pellis SM (1997b) Analysis of limb use by control rats and unilateral DA-depleted rats in the Montoya staircase test movements, impairments and compensatory strategies. Behav Brain Res 89 167-177. 

Pan W, Kashn AJ, Pick CG (2005) The staircase test in mice after spinal cord injury, hit J Neuroprotect Neuroregen 1 32—37. 

Always with the material of the previous sample problems, it has been run another experimental campaign to assess the fatigue limit of the carbon steel by the staircase test method. On the base of the S-N curves of Fig. 5.21 it has been chosen an initial stress amplimde of 225 MPa at a run out of 1,000,000 cycles and a step size d = 10 MPa. Twenty-six button hourglass specimens of 8 mm minimum diameter have been used aU having the same surface finish of the real work pieces to be built. The results of the testing campaign are shown in Fig. 5.24. Fourteen specimens failed and 12 run out at 1,000,000 cycles. Therefore, the low frequency event of run out has been selected for calculations. The characteristic quantities are iV = 12, A = 19 and B = 37 (see Eq. 5.37). 

Fig. 5.25 Fatigue limit at 10° cycles inferred by staircase test method, shown on the previously determined S-N diagrams...

T.W. Anderson et al, NAVORD Rept 65-46 (1946) described seven varieties of staircase method including the Bruceton test. Natrella (Ref 42a) also gives several References to other discussions of the up-and-down or staircase method of testing... 

Run-Down Method. A statistical testing procedure developed at Frankford Arsenal, Philadelphia (Ref 1) which produces a more complete frequency and probability of reaction curve than the Bruceton, up-and-down, or staircase methods (see under Impact, Initiation of Explosion by in Vol 7, 136-R to I37-L). Although a larger number of tests is used than in the latter procedures, the method makes possible a better evaluation of the distribution of the population. Starting at a level expected to be between 0%... 

Figure 2. The "Spiral Staircase" geometry used in the original DECO test calculations...

Figure 6 Current densities showing the behavior of two catalysts (Pt-Ru and Pt-Ru-Mo) toward the oxidation of 1 M methanol in 0.1 M HCIO4 measured at 400 mV versus RHE after 5 minutes, following different staircase potential to test the stability of the ternary electrode.

The up-and-down method, also called the Bruceton or staircase method, is a widely used statistical procedure for the determination of the height at which 50% of the samples detonate or react and its standard deviation [17,18]. The advantages and disadvantages of the method are described elsewhere [18-20] basically the test gives a reliable 50% value but not a reliable standard deviation. The number of tests required at each height also has been investigated [21]. 

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