Effect of extended training on generalization of latent inhibition: an instance of perceptual learning

Four experiments examined generalization of latent inhibition (LI) as a function of the length of preexposure in a conditioned taste aversion procedure with rats. Experiment 1 showed that one or four nonreinforced presentations of a flavor compound (BX) retarded subsequent conditioning to another compound (AX). However, after eight presentations of BX, conditioning to AX occurred at the same rate as with no preexposure. These results indicate that generalization of LI decreased as the length of preexposure to BX increased. Experiment 2 replicated this effect of reducing generalization, as well as demonstrating that LI actually increased as the length of preexposure to AX increased. Experiment 3 extended the generality of the effect to a procedure in which both BX and AX were preexposed. Experiment 4 demonstrated a similar reducing-generalization effect when generalization of LI from BX to X was assessed. All of these data are consistent with the notion that prolonged preexposure to BX enhances its discriminability. Different learning mechanisms that might be responsible for this perceptual learning effect are discussed.     

Young Children’s Nutrition During the COVID-19 Pandemic Lockdown: A Comparative Study

Early Childhood Education Journal - During the COVID-19 pandemic, most countries took precautionary steps to save their citizens by initiating a lockdown and stopping all social activities by...     

Nutrition for travel

The training and competitive programmes of elite athletes incorporate travel schedules, often long journeys, across multiple time zones. In such cases, travel causes both transient fatigue and a malaise known as "jet-lag" that persists for some days. Jet-lag is due to the disturbance of the body's circadian rhythms: diurnal and performance rhythms are displaced, depending on the direction of travel and the number of time zones crossed in flight. Attention to diet and hydration is relevant during the flight and following disembarkation until adjustment to the new meridian is complete. The consequences of jet-lag on rhythms in digestion may be compounded if food preparation and hygiene are inadequate in training camps or competitive venues overseas. The irony of travel is that it often places athletes at a greater risk of failing to meet their specific nutrition goals or succumbing to illness, at a time when the demands or outcomes of performance are of greatest importance. In addition, gastrointestinal infections related to travelling are frequent among athletes. Fastidious planning and organization among the support staff is recommended before the journey to prevent any such problems arising. Equally, athletes often need special education initiatives to assist them to cope with the challenges of a new and unusual food supply, or altered access to food.     

Anatomy "steeplechase" online: necessity sometimes is the catalyst for innovation

In most medical schools, summative practical examination in Anatomy usually takes the format of a “steeplechase” (“spotters” or “bell ringers”) conducted in the gross anatomy laboratory using cadaveric material and prosected specimens. Recently, we have started to administer similar examinations online using the quiz facility in WebCT? and Moodle?. This article chronicles how we conceived and developed this method within the peculiar nature of our medical school setting. Over a five year period, practical summative examinations were organized as “steeplechase” online. The online examinations were administered using WebCT? and later Moodle? learning management software. Assessment “objects” were created from the materials available for anatomy teaching. These were digital images of cadaveric materials, radiological, and prosected specimens. In addition, short video clips of 30 seconds duration demonstrating muscle action were produced. These objects were optimized for online viewing and then uploaded onto the learning management software. A bank of questions (multiple choice or short answer type) was then created and linked to the assessment objects. These were used in place of the steeplechase in the computer laboratory. This method serves a crucial purpose in places like ours where continuous availability of human cadavers is impossible. Although time consuming initially, once questions are setup online, future retrieval, and administration becomes convenient especially where there are large batches of students. In addition, the online environment offers distinct advantages with regards to image quality, psychometric analysis of the examination and reduction of staff preparation time compared to traditional “steeplechase.” Anat Sci Educ 4: 115–118, 2011. © 2010 American Association of Anatomists.     

Experimental archaeology and historical empathy: key tools for learning about our origins / Arqueología experimental y empatía histórica: herramientas clave para la didáctica de nuestros orígenes

We propose a learning methodology based on the development of historical empathy through experimentation. Experimental archaeology is an active methodology which provides dynamism and an active role and entertainment for students, as well as provoking historical empathy in them. This combination helps the students get a better understanding of the target knowledge. This paper presents a practical illustration of historical empathy through the implementation of experimental archaeology activities.     

Acute and subacute oral toxicity of Litsea elliptica Blume essential oil in rats

Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4 000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3 488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification.