Chemical and Behavioral Ecology of the Coastal Giant Salamander (Dicamptodon tenebrosus)

Intraspecific interactions are an important factor in shaping the population structure of terrestrial salamanders. Both physical interactions and scent-marking are vital components to the establishment of territories and influence dispersion of individuals. However, little is known about the terrestrial interactions of many salamander species, particularly that of the Coastal Giant Salamander (Dicamptodon tenebrosus). In this study, I observed the first evidence for the use chemical cues by terrestrial D. tenerosus in regards to shelter selection. I also observed the first accounts of agonistic and display behavior of terrestrial D. tenebrosus. These results suggest that terrestrial D. tenebrosus utilize chemical cues in their selection of refuge sites, and that they also display aggressive, territorial behavior

Exploring the First Year of Teaching Through Focus Group Discussions, Ethno-Mimesis, A/r/tography, and Performance Ethnography

The United States is focusing on the important and worthy goal of no child being left behind and in order to accomplish this goal, we must ensure that no teacher, including the first-year teacher, is left behind. This study explores the experiences of three first-year teachers on a monthly basis and uncovers the successes, challenges, supports, and needs that they encounter. Five research questions guided this study: 1. What are the experiences of a group of first-year teachers and in what ways were these experiences challenging, supportive, or detrimental? 2. What are the benefits for the first-year teachers in meeting monthly with other first-year teachers in a non-evaluative seminar setting to reflect upon and describe their experiences? 3. What is the value in using a descriptive feedback process (Rodger\u27s 2006) in focus group discussions with first-year teachers and what effect does the process have on the reflective practices of the first-year teachers? 4. What effect does the process of creating visual have on the first year teacher\u27s ability to reflect upon and express their experiences in meaningful ways? 5. What are the implications of this study for teacher education programs, schools, districts, and induction and mentoring programs? Focus group discussions, ethno-mimesis, a/r/tography, and performance ethnography are used to explore the first-year teachers experiences. Findings from the study demonstrated that the first-year teachers endured a significant transition from student teaching to teaching and encountered unexpected situations over which they had minimal control. They faced challenges with student behaviors and stressful events such as classroom parties. They encountered varying levels of support from teammates, colleagues, principals, and parents. This study\u27s monthly seminar meetings in a non-evaluative setting were beneficial to the first-year teachers and provided them with the opportunity to focus on the development of reflective practice. This study also demonstrated that a descriptive feedback process (Rodger\u27s 2006) was detrimental rather than beneficial in conducting focus groups, but proved useful during data analysis. This stud `s use of art as a process of discovery led the first-year teachers to take more risks and teach more creatively than they would have otherwise

Exploring Children’s Experiences of Participating in a Mindfulness Intervention

In recent years there has been a rapid growth in mindfulness practices being applied to improve the health and wellbeing of those who participate. As a result mindfulness-based interventions (MBI’s) have been applied in medical and educational settings. The purpose of this piece of research is to explore children’s understanding of mindfulness following their involvement in a 12 week mindfulness based intervention. The research provides an in-depth explorative interpretation of both the pupils and the mindfulness practitioner’s experience of mindfulness. Interpretative phenomenological analysis (IPA) was employed as a method of analysis which resulted in 3 master themes being identified. The themes include ‘physiological activities promote mindfulness’, ‘cognitive elements’ and ‘states of being’. Interpretation of the findings considered participants experiences in relation to the 7 attitudinal foundations as proposed by Kabat–Zinn (1990). A number of similarities between the participants were evident, as represented in the 3 master themes. However the degree to which each individual participant expressed their awareness and understating of mindfulness varied. Therefore the findings indicated that the participants were in the process of developing their understanding of mindfulness which differed between them on a conceptual level. This study is considered of relevance for those in the profession of Educational Psychology and those interested in the application of mindfulness-based interventions to improve the health and wellbeing outcomes for children and young people. The research has made a distinctive contribution within the field of mindfulness in light of the findings. Recommendations are made to inform the practices of Educational Psychology Services with reference to the work of Educational Psychologists. Suggestions for further research have also been made to aid the direction of future research

Kinematic Analysis of Prey Capture in Coastal Giant Salamanders (Dicamptodon tenebrosus)

Salamanders use a variety of techniques to capture prey that involves a combination of lingual and jaw prehension. For example, some plethodontid salamanders often use ballistic tongue projection to capture prey. Salamanders of the family Dicamptodontidae, are the largest sized terrestrial salamanders in the world which feed on a diverse array of prey items (arthropods, annelids, small mammals, and reptiles). Objectives of our study were to describe and quantify the behavior of terrestrial adult coastal giant salamanders (D. tenebrosus). While there has been much research conducted on aquatic phase D. tenebrosus, little is known about their terrestrial counterparts. Feeding bouts of three distinct prey types (e.g., crickets, earthworms, and slugs) were recorded using high-speed video (420-1000 frames/second) recorded with a Casio Exlim EX-ZR100 digital camera. For a feeding trial, salamanders were offered a prey item with forceps. Trials were repeated on separated days with each salamander (N=12) being exposed to equal ratios of prey items. Videos were analyzed for velocity of initial strike, lingual projection, lower and upper jaw prehension, and feeding success. Non-metric multi-dimensional scaling analysis indicated significant differences in feeding patterns among prey types. Lingual prehension was the prominent method of ingestion when a small prey item was offered (crickets) and the use of upper and lower mandible were used in a snapping motion with larger prey items (earthworms). Future work will incorporate different prey items, as well as examine prey preference and foraging behaviors of D. tenebrosus. Additionally some comparative analysis will be conducted using the tiger salamander (Abystoma tigrinum) and the tailed frog (Ascaphus truei) on the mechanics of prey capture in amphibian taxa

A hafted halberd excavated at Trecastell, Powys: from undercurrent to uptake – the emergence and contextualisation of halberds in Wales and North-west Europe

Excavations at Trecastell, Powys, south Wales, in 2007 yielded a copper halberd complete with its haft-grip. This has major implications for the mode of hafting halberds, but the discovery has also prompted a reconsideration of insular halberds in their north-west European context. Understanding the relationships between different types of halberd and different regional groups continues to be hampered by the dearth of good dating evidence, but the creation of better classifications for British and Irish weapons and new radiocarbon dates on two examples, one being Trecastell, have allowed a new developmental scheme to be advanced.The emergence of metal-headed halberds is considered more generally. While it is acknowledged that halberd-like implements pre-existed in other materials in some parts of Europe, it is argued that the appearance of metal-headed halberds depended on the transmission of a particular set of metallurgical and related skills. A new model for the vigorous uptake of halberds on a regional basis helps explain the patchiness and anachronism of halberd hotspots.The Trecastell halberd adds to one of the significant concentrations of the weapon type in Britain and prompts a more general review of the earliest metalwork from Wales and the Marches. For the Chalcolithic, halberds are instrumental in identifying a major contrast in depositional behaviour; this contrast dissolves at the beginning of the Early Bronze Age when a ‘new deposition ground’ is established. The former is attributed to the existence of a regional group across much of the region for whom the halberd served as a cultural icon, while the latter may relate to the demise of this enshrined value for the halberd.</jats:p

Widespread recombination, reassortment, and transmission of unbalanced compound viral genotypes in natural arenavirus infections.

Arenaviruses are one of the largest families of human hemorrhagic fever viruses and are known to infect both mammals and snakes. Arenaviruses package a large (L) and small (S) genome segment in their virions. For segmented RNA viruses like these, novel genotypes can be generated through mutation, recombination, and reassortment. Although it is believed that an ancient recombination event led to the emergence of a new lineage of mammalian arenaviruses, neither recombination nor reassortment has been definitively documented in natural arenavirus infections. Here, we used metagenomic sequencing to survey the viral diversity present in captive arenavirus-infected snakes. From 48 infected animals, we determined the complete or near complete sequence of 210 genome segments that grouped into 23 L and 11 S genotypes. The majority of snakes were multiply infected, with up to 4 distinct S and 11 distinct L segment genotypes in individual animals. This S/L imbalance was typical: in all cases intrahost L segment genotypes outnumbered S genotypes, and a particular S segment genotype dominated in individual animals and at a population level. We corroborated sequencing results by qRT-PCR and virus isolation, and isolates replicated as ensembles in culture. Numerous instances of recombination and reassortment were detected, including recombinant segments with unusual organizations featuring 2 intergenic regions and superfluous content, which were capable of stable replication and transmission despite their atypical structures. Overall, this represents intrahost diversity of an extent and form that goes well beyond what has been observed for arenaviruses or for viruses in general. This diversity can be plausibly attributed to the captive intermingling of sub-clinically infected wild-caught snakes. Thus, beyond providing a unique opportunity to study arenavirus evolution and adaptation, these findings allow the investigation of unintended anthropogenic impacts on viral ecology, diversity, and disease potential

Properties of the Soluble and Membrane-Bound Forms of Acetylcholinesterase Present in Pig Brain

Approximately 150/o of the total acetylcholinesterase (AChE) activity of pig brain cortex can be extracted in dilute buffer solution and the properties of this »soluble« form of the enzyme have been compared with the membrane bound enzyme which was brought into solution by extraction with 1-0/o Triton X-100 or 1 mM EDTA. The activity of the »soluble« enzyme against a range of ·substrates is identical to the membrane enzyme. The variation of activity with pH and substrate concentration are similar for the two phyisical forms of the AChE. Gradient polyacrylamide gel electrophoresis demonstrated the similarities of the »soluble« and detergent solubilized enzyme preparations. Three molecular weight species were common to both preparations: 353 000, 262 000, and 68 000 and in addition the »soluble« enzyme had a band of mol. wt. 135 000 while the Triton X - 100 extract contained species of mol. wt. 181 000 and 83 000. The membrane AChE showed a break in the Arrhenius plot with a transition temperature of 27 °c and this was abolished with detergent. In contrast the »soluble« enzyime showed no break in the Arrhenius plot suggesting the absence of associated membrane material. There are however more similarities than differences between the two physical forms of the enzyme which appear to be closely related

Effect of cytisine on some brain and hepatic biochemical parameters in spontaneously hypertensive rats

Tobacco smoking is a risk factor for variety of cardio-vascular diseases, such as hypertension, myocardial infarction, stroke and many others. It is of great importance for hypertensive patients to stop smoking. One of the medicines widely used for smoking cessation in Bulgaria is the original Bulgarian product Tabex®, which is developed on the basis of natural plant alkaloid cytisine. The aim of the following study was to ivestigate the effects of cytisine on some brain and hepatic biochemical parameters in spontaneously hypertensive rats (SHR), an widely used rodent model for human essential hypertension, and to compare the obtained results with their age-matched normotensive controls Wistar Kyoto (WKY). Multiple cytisine administration did not affect the activity of ethylmorphine-N-demethylase (EMND) and anylinehydroxylase (AH), as well as the quantity of cytochrome P 450, nor in WKY neither in SHR In the liver cytisine increased the MDA quantity both in SHR and in WKY, by 25% (p<0.05) and by 29% (p<0.05) respectively, while the GSH level was not significantly changed by the compound in both strains. In contrast, on the brain level, cytisine administration to SHR caused more prominent toxicity, resulted in GSH depletion and increased MDA quantity, while in WKY strain did not exert any toxicity. Cytisine did not significantly affect ALAT and ASAT activity in both strains. In conclusion, the results of our study suggest higher brain toxicity of cytisine in spontaneously hypertensive rats, that might be due to their pathophysiological characteristics