Correlates of variability in killer whale stereotyped call repertoires.

Killer whales vocalisations include repertoires of stereotyped call types (Ford 1984). There is strong evidence that these vocalisations are learnt (Hoelzel and Osborne 1986; Bain 1989; Deecke et al. 2000; Yurk et al. 2002). Call types can be group specific or shared amongst a number of groups, depending upon the social structure of the population or the call type (Ford 1991; Deecke 2003). It is thought that these call types function in the group cohesion and coordination (Hoelzel and Osborne 1986; Ford 1989 1991; Miller 2000, 2002). Some call types contain two overlapping, independently modulated, components each having different transmission properties (Miller 2002), these call types have a higher estimated active space than single- component call types (Miller 2006).This thesis investigates the evolution of these call type repertoires, focusing on call type usage and structure of the Southern Resident population over a period of 27 years, but including comparisons with other populations. I present evidence of hetero-specific mimicry and further evidence for vocal production and usage learning in killer whales. I compared the relative frequency of use of call types between two time periods (1977-81 & 2001-2003) and between contexts, such as direction changes with directional travel and multi-pod aggregations with single pods. I found a strong correlation of relative call type usage for each pod between the two time periods and each pod was easily acoustically distinguishable from the other two pods in both periods. The implications of these results for a role of call type repertoires in kin recognition are discussed. The least cohesive pod produced a significantly higher proportion of two-component call types than the other two more cohesive pods. Lone whales separated from their pod also used a rare subset of two-component call types rather than their pod's main call types. In recordings of multi-pod aggregations I recorded a high proportion of the same subset of two-component call types not commonly produced by any of the three pods individually, these call types were used in significantly higher proportions when all three pods were converging or socialising rather than travelling. These contextual correlates suggest that call types are selectively used and shared between groups based on their transmission properties. Each of the Southern Resident pods, J к and L, were found to increase the duration of their primary call type 10-15% in the presence of vessel noise in recordings made between 2001 & 2003. This response was not detected in recording from two earlier time periods, (1977 or 1989-1992). This change in behaviour correlated with an increase over the past decade in vessel presence around this population and may be an anti-masking strategy. I also compared the range and mean minimum and maximum fundamental frequency of the call types within the repertoires of six North Pacific killer whale populations. There was a degree of homogeneity in the range of call type fundamental frequencies within the repertoires of populations of the same ecotype, but differences between ecotypes. Offshore call types generally had a higher pitch fundamental frequency than transient or resident call types. All three resident populations had call types in their repertoires that had a maximum fundamental frequency 3 kHz higher than found in any transient call type

Fourier Analysis and Optimization of Inductive Wireless Power Transfer for Electric Vehicle Charging

With the growth of electric vehicle (EV) popularity, different charging options to increase user convenience and reduce charging time such as high power wireless charging are increasingly being developed and researched. Inductive wireless power transfer (WPT) systems for EVs must meet specifications such as stray field, battery power and voltage operating range, efficiency, and ground clearance. The coil geometry and design have a large impact in meeting these constraints. Typical design approaches include iterative analysis of predetermined coil geometries to identify candidates that meet these constraints. This work instead directly generates WPT coil shapes and magnetic fields to meet specifications and constraints through the optimization of Fourier basis function coefficients and that can be used to predict system efficiency and performance. The proposed Fourier Analysis Method (FAM) applies to arbitrary planar coil geometries and does not rely on iterative finite-element analysis (FEA) simulations. This flexibility allows for rapid design evaluation across a larger range of coil geometries and specifications. The method is used to consider the trade-off of coil current and stray field for given power levels to illustrate the flexibility and generality of the method. A 6.6 kW proof-of-concept demonstrator WPT system is built from the optimization result to compare model efficiency, stray fields, and performance to experimental measurements. The methodology is then used in the optimization, design, analysis, and testing of two 120 kW demonstrators, including thermal modeling and integration

EFFECT OF ERGOT ALKALOIDS ON BOVINE FOREGUT VASCULATURE, NUTRIENT ABSORPTION, AND EPITHELIAL BARRIER FUNCTION

Ergot alkaloids present in endophyte-infected (E+) tall fescue are thought to be the causative agent of fescue toxicosis, a syndrome affecting cattle in the eastern United States. Many of the observed signs of fescue toxicosis are thought to be attributed to peripheral vasoconstriction; however, there are data indicating that ergot alkaloids can alter blood flow to the gut. An experiment was conducted using right ruminal artery and vein collected from heifers shortly after slaughter. Vessels were mounted in a multi-myograph to determine the vasoconstrictive potentials of ergot alkaloids present in E+ tall fescue. Results indicated ergot alkaloids have the potential to induce vasoconstriction of foregut vasculature. A second experiment was conducted to determine if the additional ergot alkaloids present in E+ tall fescue increase the vasoconstrictive response above that of ergovaline. Results indicated that ergovaline is the main alkaloid responsible for vasoconstriction in bovine vessels. A third study was performed to determine the effect of ergot alkaloids on ruminal epithelial blood flow in the washed rumen of steers exposed to E+ or endophyte-free (E-) tall fescue seed. Steers were dosed with seed followed by a washed rumen experiment with differing levels of ergovaline incubated in the rumen. Results indicated that E+ tall fescue seed treatment reduced ruminal epithelial blood flow. Additionally, incubating ergovaline in the rumen during the washed rumen further decreased epithelial blood flow and volatile fatty acid (VFA) absorption. A final study was conducted to determine the acute effects of ergot alkaloids on isolated rumen epithelial absorptive and barrier functions and the potential for ruminal ergovaline absorption. Results indicate that acute exposure to ergot alkaloids does not alter the absorptive or barrier function of rumen epithelium and ergovaline is absorbed from the rumen. Data from this series of experiments have shown that ergot alkaloids from E+ tall fescue can induce vasoconstriction of blood vessels in the foregut of cattle, reduce blood flow to the rumen epithelium, and decrease VFA absorption. The decrease in nutrient absorption could contribute to the observed symptoms of fescue toxicosis, including depressed growth rates and general unthriftiness

Effect of Urea and Distillers Inclusion in Dry- Rolled Corn Based Diets on Heifer Performance and Carcass Characteristics

Crossbred heifers (n=96, BW = 810 ± 20) were utilized to evaluate the effects of increasing wet distillers grains plus solubles and urea inclusion in a dry rolled corn based finishing diet on performance and carcass characteristics. Heifers were individually fed using a calan gate system with a 2 × 2 factorial arrangement of treatments. Factors included distillers inclusion at either 10 or 20% of diet DM and urea inclusion at either 0.2 or 1.4% of diet DM. Th ere was no difference for final body weight, average daily gain, and feed conversion on a live or carcass adjusted basis for either urea or distillers inclusion in the diet. Dry matter intake was reduced with increased urea inclusion; however, distillers inclusion did not influence intake. Added distillers and urea in the diet had minimal impact on performance suggesting supplemental urea in a dry rolled corn based finishing diets is of minimal benefit when feeding at least 10% distillers grains

Admixture between ancient lineages, selection, and the formation of sympatric stickleback species-pairs

Ecological speciation has become a popular model for the development and maintenance of reproductive isolation in closely related sympatric pairs of species or ecotypes. An implicit assumption has been that such pairs originate (possibly with gene flow) from a recent, genetically homogeneous ancestor. However, recent genomic data have revealed that currently sympatric taxa are often a result of secondary contact between ancestrally allopatric lineages. This has sparked an interest in the importance of initial hybridization upon secondary contact, with genomic reanalysis of classic examples of ecological speciation often implicating admixture in speciation. We describe a novel occurrence of unusually well-developed reproductive isolation in a model system for ecological speciation: the three-spined stickleback (Gasterosteus aculeatus), breeding sympatrically in multiple lagoons on the Scottish island of North Uist. Using morphological data, targeted genotyping, and genome-wide single-nucleotide polymorphism data, we show that lagoon resident and anadromous ecotypes are strongly reproductively isolated with an estimated hybridization rate of only ∼1%. We use palaeoecological and genetic data to test three hypotheses to explain the existence of these species-pairs. Our results suggest that recent, purely ecological speciation from a genetically homogeneous ancestor is probably not solely responsible for the evolution of species-pairs. Instead, we reveal a complex colonization history with multiple ancestral lineages contributing to the genetic composition of species-pairs, alongside strong disruptive selection. Our results imply a role for admixture upon secondary contact and are consistent with the recent suggestion that the genomic underpinning of ecological speciation often has an older, allopatric origin

It’s a Hard-Knock Life: Child Labor Practices and Compliance with IMF Agreements

How does IMF lending impact child labor? We argue that, as compliance with IMF reforms increases, child labor increases. IMF loans can help governments avoid bankruptcy, prevent debt defaults, and credibly signal a commitment to pro-market reforms which should generate trade and investment. However, IMF policies associated with revenue and social policies can have negative impacts on child labor. Education reforms undermine the quality of schooling, making child labor more likely. Healthcare reforms undermine the quality of healthcare; when parents are ill or injured, their children are more likely to enter the workforce to make up for lost income. Similarly, social safety net reforms reduce the ability of families to access a safety net during times of hardship and make it more likely that children are pushed into the labor market to keep families afloat. To test our argument, we use a control function selection model on a sample of 70 IMF borrowers between 2002 and 2016. Using new datasets on IMF compliance and child labor, we find that increased compliance with IMF reforms worsens child labor practices. Revenue and social policy compliance in particular are associated with an increase in child labor

Connexin 43 plays a role in pulmonary vascular reactivity in mice

Pulmonary arterial hypertension (PAH) is a chronic condition characterized by vascular remodeling and increased vaso-reactivity. PAH is more common in females than in males (~3:1). Connexin (Cx)43 has been shown to be involved in cellular communication within the pulmonary vasculature. Therefore, we investigated the role of Cx43 in pulmonary vascular reactivity using Cx43 heterozygous (Cx43+/−) mice and 37,43Gap27, which is a pharmacological inhibitor of Cx37 and Cx43. Contraction and relaxation responses were studied in intra-lobar pulmonary arteries (IPAs) derived from normoxic mice and hypoxic mice using wire myography. IPAs from male Cx43+/− mice displayed a small but significant increase in the contractile response to endothelin-1 (but not 5-hydroxytryptamine) under both normoxic and hypoxic conditions. There was no difference in the contractile response to endothelin-1 (ET-1) or 5-hydroxytryptamine (5-HT) in IPAs derived from female Cx43+/−mice compared to wildtype mice. Relaxation responses to methacholine (MCh) were attenuated in IPAs from male and female Cx43+/− mice or by pre-incubation of IPAs with 37,43Gap27. Nω-Nitro-L-arginine methyl ester (l-NAME) fully inhibited MCh-induced relaxation. In conclusion, Cx43 is involved in nitric oxide (NO)-induced pulmonary vascular relaxation and plays a gender-specific and agonist-specific role in pulmonary vascular contractility. Therefore, reduced Cx43 signaling may contribute to pulmonary vascular dysfunction

Vocal behaviour and feeding ecology of killer whales Orcinus orca around Shetland, UK

Killer whales Orcinus orca are sighted regularly off Shetland, UK, but little is known about their numbers, diet and population identity. We aimed to relate vocal behaviour to diet of killer whales around Shetland in order to investigate population structure and differences in feeding strategies. Fieldwork was conducted in the summers of 2008 and 2009. We located killer whales through a sightings network and shore-based scans and collected photo-ID data, behavioural information, feeding data and acoustic recordings from a small boat. The majority of encounters (n = 14) were of small groups (1 to 15 individuals) travelling close to shore and feeding on marine mammals. Two encounters were with large groups (20+ individuals) feeding on herring Clupea harengus farther offshore. Seal-hunting groups vocalised rarely, producing pulsed calls, echolocation clicks and whistles almost exclusively when surface-active or milling after a kill. Herring-eating groups were largely silent during one encounter, but very vocal during the other. Analysis of pulsed calls identified 6 stereotyped call types for seal-hunting groups and 7 for herring-eating groups. No call types were shared between both kinds of groups. The vocal behaviour of seal-hunting groups showed striking parallels to that of Pacific marine mammal specialists and presumably evolved to decrease detection by acoustically sensitive prey. One call type produced by Shetland herring-eating killer whales matched a vocalisation that a previous study had described from Iceland and identified as a possible herding call that may function to concentrate herring during feeding. These findings point to behavioural and dietary specialisation among Shetland killer whales, which should be taken into account when making management decisions affecting these animals