The Influence of Body Temperature on Motion Patterns on Anolis Lizard Visual Display

Anolis sagrei has a display in the form of bobbing its head up and down. In order to more accurately understand the communication and honesty of the display two experiments were done. Honesty, in reference to it being an honest signal; meaning that this form of communication is correlated with the condition of the animal. The first experiment examined the lizards in a recreated environment. By controlling the temperature of the setting and recording the interaction we were able to determine how changing the temperature could cause a difference in display. The second experiment examined the lizard\u27s ability to see rapid and sharp movements. By watching lizards\u27 reactions to different frequency dot movements we could determine if changes in speed of a display would be visible to the lizard. In the first experiment, we found that the cold temperature caused the display to be significantly slower than in warmer temperature. In the second experiment, we found that the lizard responded most positively to the faster, more abrupt movements and therefore would be able to notice different speeds of the display. The connection of temperature to the display, as well as the knowledge that it is visible to the lizard, allowed us to conclude that the lizard\u27s display is an honest signal

The Summer Resident Birds of Polk County, Iowa - A Guide to Local Study

This paper consists of notes on the more common summer-resident birds of Polk County, Iowa. Its purpose is not to give an exhaustive treatment of the subject, but merely to include those birds which the true, faithful student can expect to find nesting in this county every summer

Cranial sutures work collectively to distribute strain throughout the reptile skull

The skull is composed of many bones that come together at sutures. These sutures are important sites of growth, and as growth ceases some become fused while others remain patent. Their mechanical behaviour and how they interact with changing form and loadings to ensure balanced craniofacial development is still poorly understood. Early suture fusion often leads to disfiguring syndromes, thus is it imperative that we understand the function of sutures more clearly. By applying advanced engineering modelling techniques, we reveal for the first time that patent sutures generate a more widely distributed, high level of strain throughout the reptile skull. Without patent sutures, large regions of the skull are only subjected to infrequent low-level strains that could weaken the bone and result in abnormal development. Sutures are therefore not only sites of bone growth, but could also be essential for the modulation of strains necessary for normal growth and development in reptiles

Impurity segregation in graphene nanoribbons

The electronic properties of low-dimensional materials can be engineered by doping, but in the case of graphene nanoribbons (GNR) the proximity of two symmetry-breaking edges introduces an additional dependence on the location of an impurity across the width of the ribbon. This introduces energetically favorable locations for impurities, leading to a degree of spatial segregation in the impurity concentration. We develop a simple model to calculate the change in energy of a GNR system with an arbitrary impurity as that impurity is moved across the ribbon and validate its findings by comparison with ab initio calculations. Although our results agree with previous works predicting the dominance of edge disorder in GNR, we argue that the distribution of adsorbed impurities across a ribbon may be controllable by external factors, namely an applied electric field. We propose that this control over impurity segregation may allow manipulation and fine-tuning of the magnetic and transport properties of GNRs.Comment: 5 pages, 4 figures, submitte

Tonsillectomy rates in the South African private healthcare sector

Background. Adeno-/tonsillectomy is a commonly performed procedure with internationally standardised and recognised indications.Despite this, there exists considerable international (190 - 850/100 000 people ≤19 years of age) and regional variation in rates. This cannotbe accounted for by differences in clinical need or regional morbidity.Objectives. To describe the adeno-/tonsillectomy rate in the South African (SA) private healthcare sector and regional variations thereof. Tocompare local rates with international rates and assess trends in adeno-/tonsillectomy practice.Methods. Analysis of 2012 and 2013 adeno-/tonsillectomy data provided by the largest SA private healthcare funder, accounting for 30% ofthe medical scheme market. Rates are expressed per 100 000 people ≤19 years of age.Results. The tonsillectomy rate in the SA private healthcare sector was 1 888/100 000 people ≤19 years of age in 2012. In 2013, the ratedropped significantly (p<0.001) to 1 755/100 000. This is more than double the highest national tonsillectomy rate reported in the literature.There was also considerable regional variation in this rate within SA.Discussion. The SA tonsillectomy rate is very high when compared with international trends and varies regionally within the country. Theliterature does not support an increased burden of disease as the reason behind this. Rather, it is differences in training and clinical practiceof clinicians, as well as social and family factors, that have been implicated.Conclusion. The adeno-/tonsillectomy rate in the SA private healthcare sector is substantially higher than international norms. The reasonsfor this discrepancy require further consideration

Quinsy tonsillectomy or interval tonsillectomy - a prospective randomised trial

Fifty-one patients with peritonsillar abscesses were randomised to undergo either quinsy tonsillectomy (aT) or interval tonsillectomy (IT), and the two groups were compared. The QT group lost fewer (10,3 v. 17,9) working days and less blood during the operation (158,6 ml v. 205,7 ml); haemostasis was easier and the operation was technically simpler in this group. There was no significant difference in length of hospital stay and neither group had intra- or postoperative complications. Only 64% of the IT group returned for tonsillectomy. In this study QT had distinct advantages over drainage and IT in the management of peritonsillar abscesses