Fourth Trial: Society

2018 ◽  
pp. 155-182
Keyword(s):  
1976 ◽  
Vol 54 (6) ◽  
pp. 896-900 ◽  
Author(s):  
S. F. H. Threlkeld ◽  
L. Bentley ◽  
A. Yeung ◽  
K. Henriksen

Starved Drosophila melanogaster were run individually in a T maze in which sucrose was provided as a reward. After three trials, flies were run similarly for a fourth trial in a clean maze lacking sucrose. The time in which the food area was located in the fourth trial compared with the first was significantly decreased. Control experiments rule out the possibility that smell. pheromones, or increased energy levels associated with the ingestion of sucrose are the basis of the highly significant differences. A likely alternative is that the flies to some degree learn the location of the food area.


2005 ◽  
Vol 71 (9) ◽  
pp. 4986-4991 ◽  
Author(s):  
Patrick F. McDermott ◽  
Patti Cullen ◽  
Susannah K. Hubert ◽  
Shawn D. McDermott ◽  
Mary Bartholomew ◽  
...  

ABSTRACT The extent of transfer of antimicrobial resistance from agricultural environments to humans is controversial. To assess the potential hazard posed by streptogramin use in food animals, this study evaluated the effect of virginiamycin exposure on antimicrobial resistance in Enterococcus faecium recovered from treated broilers. Four consecutive broiler feeding trials were conducted using animals raised on common litter. In the first three trials, one group of birds was fed virginiamycin continuously in feed at 20 g/ton, and a second group served as the nontreated control. In the fourth trial, antimicrobial-free feed was given to both groups. Fecal samples were cultured 1 day after chickens hatched and then at 1, 3, 5, and 7 weeks of age. Isolates from each time point were tested for susceptibility to a panel of different antimicrobials. Quinupristin/dalfopristin-resistant E. faecium appeared after 5 weeks of treatment in trial 1 and within 7 days of trials 2 to 4. Following removal of virginiamycin in trial 4, no resistant isolates were detected after 5 weeks. PCR failed to detect vat, vgb, or erm(B) in any of the streptogramin-resistant E. faecium isolates, whereas the msr(C) gene was detected in 97% of resistant isolates. In an experimental setting using broiler chickens, continuous virginiamycin exposure was required to maintain a stable streptogramin-resistant population of E. faecium in the animals. The bases of resistance could not be explained by known genetic determinants.


HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 1062A-1062
Author(s):  
Tory Schmidt ◽  
Don Elfving ◽  
Jim McFerson

In three trials, 2004 crop loads were adjusted at the balloon stage of blossom development on heavily cropped whole apple trees by clipping all flower pedicels within a cluster while leaving the spur intact. Trees were adjusted to 0% crop (all flowers removed), 50% crop (half of all clusters removed), or left as 100% crop (no flowers removed). On `Cameo'/Bud.9, 400 ppm GA4+7 were applied to trees of each crop level at petal fall, 10 mm, 20 mm, or left unsprayed. At each crop load, GA4+7 marginally diminished the 2005 return bloom regardless of application timing, but the 2004 crop level was far more influential in 2005 flowering. In a second `Cameo'/Bud.9 trial, 0, 300, 600, or 900 ppm ethephon were applied to whole trees of each crop level at 45 DAFB. Ethephon generally demonstrated a rate response in improving the 2005 return bloom, but the 2005 flowering was more dramatically influenced by 2004 crop levels. On `Honeycrisp'/M.9, 300 ppm GA4+7 were applied to whole trees of each crop level at 10 mm. GA4+7 diminished 2005 return bloom at the 50% crop load, but spray effects were not as clear at the extreme 2004 crop levels. These results suggest that commercial floral inhibitors and promoters have difficulty overcoming endogenous effects of heavy or light bloom and crop in severely alternating apple trees. In a fourth trial, lightly cropped organic `Fuji'/MM.106 trees were sprayed with 0, 150, 300, or 450 ppm GA4 at petal fall, 10 mm, or 20 mm timings in 2004. The 2005 return bloom was inversely correlated with spray rates, with 10 mm showing more floral inhibition than other timings. Overall, `Cameo' was less sensitive to GA and ethephon than `Honeycrisp' or `Fuji'.


1960 ◽  
Vol 55 (2) ◽  
pp. 261-267 ◽  
Author(s):  
J. M. Holder

1. Three trials are reported in which the grazing behaviour of separate groups of cows, one receiving supplementary food, either as conserved roughage, concentrate or fodder crop, was observed over 24 hr. periods. A fourth trial, assessing the effect of summer temperatures on unshaded milking cows, is briefly described.2. In trials 1 and 2 the stall feeding of either conserved roughage or concentrate reduced grazing as compared with unsupplemented cows by approximately 10%.3. Allowing access to a fresh ‘strip’ of a fodder crop at a set time each day, whilst not altering total grazing time, very markedly altered periodicity of grazing. Cows delayed grazing up to 3 hr. whilst awaiting a fresh ‘strip’.4. Environmental temperatures up to 87° F. did not alter total grazing time as compared with grazing time when temperature reached a maximum of only 70° F.5. The value of supplementary feeding of dairy cattle at pasture, at least where the intake of pasture is sufficient for maintenance and a low level of production, appears to be open to question.


1974 ◽  
Vol 34 (1) ◽  
pp. 335-338 ◽  
Author(s):  
Kerm Henriksen ◽  
John P. Fleming ◽  
Donna L. Pilichowski

Previous studies have reported acoustic factors to be of little importance in the release from proactive-inhibition methodology. 96 Ss were run to investigate whether words are encoded acoustically in the release from proactive-inhibition paradigm. Half of the Ss experienced acoustically similar triads for 4 trials; the other half were shifted to an acoustically different triad on the fourth trial. Proactive inhibition increased for both groups during the first 3 trials. Release from proactive inhibition was obtained on the fourth trial for the shifted group. The changes in proactive inhibition were interpreted as encoding along the acoustic dimension.


2016 ◽  
Vol 44 (3) ◽  
pp. 650-676 ◽  
Author(s):  
JOHN P. BUNCE ◽  
ROSE M. SCOTT

AbstractWhile recent studies suggest children can use cross-situational information to learn words, these studies involved minimal referential ambiguity, and the cross-situational evidence overwhelmingly favored a single referent for each word. Here we asked whether 2·5-year-olds could identify a noun's referent when the scene and cross-situational evidence were more ambiguous. Children saw four trials in which a novel word occurred with four novel objects; only one object consistently co-occurred with the word across trials. The frequency of distracter objects varied across conditions. When all distracter referents occurred only once (no-competition), children successfully identified the noun's referent. When a high-probability competitor referent occurred on three trials, children identified the target referent if the competitor was absent on the third trial (short-competition) but not if it was present until the fourth trial (long-competition). This suggests that although 2·5-year-olds’ cross-situational learning scales up to more ambiguous scenes, it is disrupted by high-probability competitor referents.


1984 ◽  
Vol 38 (3) ◽  
pp. 469-475 ◽  
Author(s):  
A. E. Carden ◽  
A. J. Webb

ABSTRACTThe effect of age on incidence of susceptibility to halothane anaesthesia in pigs was studied on animals that were repeatedly exposed to the anaesthetic. In three trials, 232 Piétrain/Hampshire and 201 Landrace pigs were given three 3-min halothane tests, at 19, 35 and 54 days of age. In a fourth trial 253 Landrace pigs received four 5-min tests, at 21, 35, 49 and 63 days. All pigs were offspring of positive × positive matings. Maximum-likelihood estimates of the probability of positive reactions were 0·47, 0·73 and 0·88 at the three ages in Pietrain/Hampshire; 0·20, 0·63 and 0·60 in the first Landrance trial; and 0·64, 0·86, 0·84 and 0·90 in the second Landrace trial. Thus, in all trials, the incidence of halothane positive reactions increased with age. In both breeds and at all ages, the incidence was lower in males than in females.


1982 ◽  
Vol 51 (2) ◽  
pp. 463-470
Author(s):  
Pierre-Philippe Morin ◽  
Raymond Ducharme ◽  
Harold Flash

40 subjects were required to memorize different word lists. Each list contained three words, and each list corresponded to one trial. The Brown-Peterson paradigm was employed to induce proactive memory interference. For the experimental group the first three lists belonged to a negative affective encoding category, while the fourth belonged to a different encoding category. The control subjects memorized words from mixed encoding categories. In the experimental group proactive interference built up over trials with the same encoding category of words, resulting in a poorer performance at recall, during the second and third trials, and progressive decrease in heart rate. On the fourth trial of the Brown-Peterson task, proactive interference ceased, resulting in better recall than the previous interference trials, concomitantly with an increase in heart rate. These results are discussed within the context of Lacey's hypothesis, according to which, heart rate should increase with cognitive activity requiring rejection of environmental stimuli.


2007 ◽  
Vol 16 (2) ◽  
pp. 85-92 ◽  
Author(s):  
Ulrike H. Mitchell ◽  
J. William Myrer ◽  
J. Ty Hopkins ◽  
Iain Hunter ◽  
J. Brent Feland ◽  
...  

Context:Some researchers have suggested that an alteration of stretch perception could be responsible for the success of the contract-relax (CR) stretch, a stretch technique derived from proprioceptive neuromuscular facilitation (PNF).Objective:This study was conducted to determine if the alteration of the stretch perception is a possible explanation for the range of motion (ROM) gains of the CR stretch.Participants:Eighteen subjects performed two stretches in randomized order: the slow stretch and the CR stretch.Main Outcome Measure:The stretch intensity was controlled. The stretch force was measured and compared between the slow stretch and CR stretch.Results:There was a significant difference between the stretch force that could be applied in the PNF stretch (126.0 N) and the slow stretch (108.4 N); P = 0.00086. The average stretch tolerance progressively increased with successive trials from 120.6 N in the first trial to 132.4 N in the fourth trial.Conclusion:The alteration of stretch perception plays a role in the success of the CR form of PNF stretching. At least four repetitions of the CR stretch are recommended to get the greatest ROM gain.


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