Estimating the active space of male koala bellows: propagation of cues to size and identity in a Eucalyptus forest

Examining how increasing distance affects the information content of vocal signals is fundamental for determining the active space of a given species’ vocal communication system. In the current study we played back male koala bellows in a Eucalyptus forest to determine the extent that individual classification of male koala bellows becomes less accurate over distance, and also to quantify how individually distinctive acoustic features of bellows and size-related information degrade over distance. Our results show that the formant frequencies of bellows derived from Linear Predictive Coding can be used to classify calls to male koalas over distances of 1–50 m. Further analysis revealed that the upper formant frequencies and formant frequency spacing were the most stable acoustic features of male bellows as they propagated through the Eucalyptus canopy. Taken together these findings suggest that koalas could recognise known individuals at distances of up to 50 m and indicate that they should attend to variation in the upper formant frequencies and formant frequency spacing when assessing the identity of callers. Furthermore, since the formant frequency spacing is also a cue to male body size in this species and its variation over distance remained very low compared to documented inter-individual variation, we suggest that male koalas would still be reliably classified as small, medium or large by receivers at distances of up to 150 m

Exploring Early College Credit Implications for Engineering

In the past decade, increasing numbers of students are taking college credit courses while still in high school, through programs such as Advanced Placement or through agreements with the local community colleges. Recognizing this trend, an Iowa State University task force researched the impact that this early college credit (ECC) was having on both the student experience and the university. The study methodology included both quantitative and qualitative analyses, using student academic records, student surveys and focus groups, faculty focus groups, and review of institutional materials. This paper disaggregates institutional findings to compare the experiences of engineering and non-engineering students. Similar to nonengineering students, engineering students with ECC had higher one-year retention rates, took fewer credits their first semester of enrollment, graduated after eight semesters of enrollment and graduated in fewer semesters overall than did engineering students without ECC. However, there were differences in the experiences between engineering students and non-engineering students. Engineering students did not see an increase in GPA or graduation rates; and, they were more likely to repeat courses taken as ECC and to have their ECC courses not count toward their degree programs. Strategies to increase the effectiveness of ECC for engineering students could include offering of key entry-level engineering courses to students in high school, a review of the engineering curriculum for sequencing and flexibility, increased attention on issues of mathematics curriculum alignment with feeder institutions, and improved communication with high school students, parents and counselors

Substrate Effect on the High Temperature Oxidation Behavior of a Pt-modified Aluminide Coating. Part II: Long-term Cyclic-oxidation Tests at 1,050 C

This second part of a two-part study is devoted to the effect of the substrate on the long-term, cyclic-oxidation behavior at 1,050 C of RT22 industrial coating deposited on three Ni-base superalloys (CMSX-4, SCB, and IN792). Cyclicoxidation tests at 1,050 C were performed for up to 58 cycles of 300 h (i.e., 17,400 h of heating at 1,050 C). For such test conditions, interdiffusion between the coating and its substrate plays a larger role in the damage process of the system than during isothermal tests at 900, 1,050, and 1,150 C for 100 h and cyclicoxidation tests at 900 C which were reported in part I [N. Vialas and D. Monceau, Oxidation of Metals 66, 155 (2006)]. The results reported in the present paper show that interdiffusion has an important effect on long-term, cyclic-oxidation resistance, so that clear differences can be observed between different superalloys protected with the same aluminide coating. Net-mass-change (NMC) curves show the better cyclic-oxidation behavior of the RT22/IN792 system whereas uncoated CMSX-4 has the best cyclic-oxidation resistance among the three superalloys studied. The importance of the interactions between the superalloy substrate and its coating is then demonstrated. The effect of the substrate on cyclic-oxidation behavior is related to the extent of oxide scale spalling and to the evolution of microstructural features of the coatings tested. SEM examinations of coating surfaces and cross sections show that spalling on RT22/CMSX-4 and RT22/SCB was favored by the presence of deep voids localized at the coating/oxide interface. Some of these voids can act as nucleation sites for scale spallation. The formation of such interfacial voids was always observed when the b to c0 transformation leads to the formation of a two-phase b/c0 layer in contact with the alumina scale. On the contrary, no voids were observed in RT22/IN792, since this b to c0 transformation occurs gradually by an inward transformation of b leading to the formation of a continuous layer of c0 phase, parallel to the metal/scale interface

Effects of dalcetrapib in patients with a recent acute coronary syndrome

In observational analyses, higher levels of high-density lipoprotein (HDL) cholesterol have been associated with a lower risk of coronary heart disease events. However, whether raising HDL cholesterol levels therapeutically reduces cardiovascular risk remains uncertain. Inhibition of cholesteryl ester transfer protein (CETP) raises HDL cholesterol levels and might therefore improve cardiovascular outcomes

News and Notes

If the first bit of news is Hamilton College\u27s effort to showcase one of its special collections and to serve as a connector for researchers interested in all aspects of communitarian endeavors, the second is the reporting of events and activities which promote learning about the contributions of these communities to society at large. Serving as correspondent for several recent gatherings dealing with matters Shaker and Harmonist, I submit the following report

News and Notes

The Synanon community site, now the Marconi Conference Center outside of Marshall, California, was the setting for the thirty-third (2006) annual meeting of the Communal Studies Association

News and Notes

News and notes related to: the Communal Studies Association annual meeting in Kirtland, Ohio; the Shelburne Museum’s exhibition: Out of this World: Shaker Design, Past, Present, and Future ; an interview of ninety-one year old Owen Edgington (a direct descendant of West Union Shakers William Edgington and Jane Johnson) by Dorothy Jones and Carol Medlicottin; a report on the signing of preservation and conservation easements by Shakers at Sabbathday Lake, Maine, to preserve nineteen community buildings and prevent future development of the property; an update on Koinonia Farm

Putting Sodus Shaker Village On The Map

The interplay of historical evidence with the researcher’s skill at historical reconstruction is what is at stake in this study of the formation of the Shaker settlement on the southern shore of the Great Sodus Bay. Although the Shaker settlement there lasted for a decade, from 1826 until 1837, attention here is on the years 1825-1827, which were the formative years of the community. Through the use of maps, and with the corroboration of Shaker journals and other writings, I will demonstrate that the Sodus Shakers did not purchase virgin land but rather a deserted, previously- settled town. This is the “what” of the article. In this case, however, the “how” — i.e., the process of discovery, the role of chance and serendipity, the need to address my own “hidden” assumptions, the mysteries created by incongruent facts and the detective work required to solve them — is perhaps of equal interest, and shapes how I will present my findings. Any historical inquiry is dependent upon artifacts from the past, which for the most part are written documents. All too often maps are not extensively used. For this study, however, I found them invaluable. When used in comparative research, maps raise some unique issues, and these will be highlighted as they apply to specific maps under discussion. Additionally, like all artifacts of human creation, maps may be flawed. Detecting errors and erroneous conclusions drawn from them is as necessary as it is a challenge. Attention, therefore, will be paid to the quality of the data gathered, and, as in all empirical research, while singular findings are important, it is when they are substantiated by other sources, i.e., independently verified, that they achieve their greatest significance

Intra- and inter-individual genetic differences in gene expression

Genetic variation is known to influence the amount of mRNA produced by a gene. Given that the molecular machines control mRNA levels of multiple genes, we expect genetic variation in the components of these machines would influence multiple genes in a similar fashion. In this study we show that this assumption is correct by using correlation of mRNA levels measured independently in the brain, kidney or liver of multiple, genetically typed, mice strains to detect shared genetic influences. These correlating groups of genes (CGG) have collective properties that account for 40-90% of the variability of their constituent genes and in some cases, but not all, contain genes encoding functionally related proteins. Critically, we show that the genetic influences are essentially tissue specific and consequently the same genetic variations in the one animal may up-regulate a CGG in one tissue but down-regulate the same CGG in a second tissue. We further show similarly paradoxical behaviour of CGGs within the same tissues of different individuals. The implication of this study is that this class of genetic variation can result in complex inter- and intra-individual and tissue differences and that this will create substantial challenges to the investigation of phenotypic outcomes, particularly in humans where multiple tissues are not readily available.

&#xa

Roaring high and low: composition and possible functions of the Iberian stag's vocal repertoire

We provide a detailed description of the rutting vocalisations of free-ranging male Iberian deer (Cervus elaphus hispanicus, Hilzheimer 1909), a geographically isolated and morphologically differentiated subspecies of red deer Cervus elaphus. We combine spectrographic examinations, spectral analyses and automated classifications to identify different call types, and compare the composition of the vocal repertoire with that of other red deer subspecies. Iberian stags give bouts of roars (and more rarely, short series of barks) that are typically composed of two different types of calls. Long Common Roars are mostly given at the beginning or at the end of the bout, and are characterised by a high fundamental frequency (F0) resulting in poorly defined formant frequencies but a relatively high amplitude. In contrast, Short Common Roars are typically given in the middle or at the end of the bout, and are characterised by a lower F0 resulting in relatively well defined vocal tract resonances, but low amplitude. While we did not identify entirely Harsh Roars (as described in the Scottish red deer subspecies (Cervus elaphus scoticus), a small percentage of Long Common Roars contained segments of deterministic chaos. We suggest that the evolution of two clearly distinct types of Common Roars may reflect divergent selection pressures favouring either vocal efficiency in high pitched roars or the communication of body size in low-pitched, high spectral density roars highlighting vocal tract resonances. The clear divergence of the Iberian red deer vocal repertoire from those of other documented European red deer populations reinforces the status of this geographical variant as a distinct subspecies