A study of the morphology of Tatenectes laramiensis, a cryptocleidoid plesiosaur from the Sundance Formation (Wyoming, USA)

Tatenectes laramiensis is a cryptocleidoid plesiosaur from the Late Jurassic Sundance Formation. This study primarily concerns a partial skeleton comprised of dorsal vertebrae, ribs, gastralia, and pelvic girdle. Even though the skeleton is incomplete, it is hypothesized that the preserved fossils are sufficient to indicate the overall body shape and also the preferred habitat of Tatenectes. Possibly the most notable of the novel characters is the pachyostotic state of the gastralia. In relation to the ribs and overall size of Tatenectes, in comparison to the gastralia in related taxa, these gastralia are disproportionately robust. The combination of these morphologies suggests a dorso-ventrally compressed body shape. A sub-cylindrical cross-section along with the low center of gravity indicated by the pachyostotic gastralia suggest that Tatenectes laramiensis inhabited shallow coastal regions

X-ray polarimetry with an active-matrix pixel proportional counter

We report the first results from an X-ray polarimeter with a micropattern gas proportional counter using an amorphous silicon active matrix readout. With 100% polarized X-rays at 4.5 keV, we obtain a modulation factor of 0.33 +/- 0.03, confirming previous reports of the high polarization sensitivity of a finely segmented pixel proportional counter. The detector described here has a geometry suitable for the focal plane of an astronomical X-ray telescope. Amorphous silicon readout technology will enable additional extensions and improvements.Comment: 4 pages, 4 figures, 1 tabl

Evidence of pachyostosis in the cryptocleidoid plesiosaur Tatenectes laramiensis from the Sundance Formation of Wyoming

In this paper we present evidence for pachyostosis in the cryptocleidoid plesiosaur Tatenectes laramiensis Knight, 1900 (O\u27Keefe and Wahl, 2003a). Pachyostosis is not common in plesiosaurs and is particularly rare in non-pliosaurian plesiosaurs, although enlarged gastralia were first recognized in Tatenectes by Wahl (1999). This study aims to investigate the nature of the disproportionately large gastralia of Tatenectes m greater depth, based on new material. A recently discovered partial skeleton consisting of a dorsal vertebral series, ribs, gastralia, and a complete pelvic girdle was collected from the Jurassic-aged Sundance Formation of the Bighorn Basin in Wyoming during the summer of 2006. The gastralia of this specimen are disproportionately large considering the small size of the taxon (about 3 meters total length), and we therefore investigated the size of these elements quantitatively. Polished cross-sections were also prepared to explore the histology of the ribs and gastralia. The ribs of Tatenectes are not pachyostotic, whereas the gastralia exhibit a novel condition of pachyostosis while lacking osteosclerosis

The Value of Literacy Practices

The concepts of literacy events and practices have received considerable attention in educational research and policy. In comparison, the question of value, that is, ‘which literacy practices do people most value?’ has been neglected. With the current trend of cross-cultural adult literacy assessment, it is increasingly important to recognise locally valued literacy practices. In this paper we argue that measuring preferences and weighting of literacy practices provides an empirical and democratic basis for decisions in literacy assessment and curriculum development and could inform rapid educational adaptation to changes in the literacy environment. The paper examines the methodological basis for investigating literacy values and its potential to inform cross-cultural literacy assessments. The argument is illustrated with primary data from Mozambique. The correlation between individual values and respondents’ socio-economic and demographic characteristics is explored

Osteology of the cryptocleidoid plesiosaur Tatenectes laramiensis, with comments on the taxonomic status of the Cimoliasauridae

Recent field work in the Bighorn Basin, Wyoming has recovered significant new material of the plesiosaur Tatenectes laramiensis. The majority of cryptocleidoid plesiosaurs have been recovered from Middle and Upper Jurassic units (Oxford and Kimmeridge Clays, respectively) in the United Kingdom, but Tatenectes laramiensis is one of at least two cryptocleidoids known from the Upper Sundance Member of the Sundance Formation (Oxfordian) of North America. Although poorly known, they bear directly on both the phylogeny and biogeography of the cryptocleidoid plesiosaurs. Here we describe new fossil material of Tatenectes, and reevaluate the phylogenetic position of this genus based on all known material. New material includes a partial skeleton comprising cranial elements, axial column, and a partial pectoral girdle, as well as an isolated humerus and vertebrae. The pectoral girdle closely resembles that of Muraenosaurus beloclis from the Oxford Clay, but is even shorter anteriorly. The cervical vertebrae are more compressed antero-posteriorly than in other Jurassic cryptocleidoids. The humerus is less derived, resembling that of Tricleidus seeleyi. Two most parsimonious trees were obtained, and the consensus tree solidifies the phylogenetic position of Tatenectes as being most closely related to the Oxford Clay taxon Kimmerosaurus

Multiple minimum coverings of Kn with copies of K4 - e

This paper is the last of a trilogy completely solving the maximum packing and minimum covering problems for the complete graph on n vertices, Kn, with copies of K4 - e, that is, the complete graph on four vertices with one edge missing

Student Repayment Crisis and the Value of Higher Education and the Economy in California’s Kern County

The cost of post-secondary education (PE) continues to increase, which has contributed to elevating federal loan demand, and as of the fourth quarter of 2020, equaling a debt of $1.56 trillion in the US. The purpose of this research was to compare two post-secondary institutions for specific alignment with the local labor market, examine institutional economic benefits and costs, and impact of loan default. Bakersfield College (BC) and California State University, Bakersfield (CSUB) are both public, Hispanic Serving Institutions, in central California. Despite similarities, loan default rates of each institution differ; six-year mean rates, 24.6% at BC, 7.7% at CSUB. The analysis revealed that although the top degrees at BC and CSUB did not align well with local labor market demands, the individual and institutional economic benefit exceeds the costs. Importantly, both the individual and institutional economic benefits are highly dependent on completing the degree, the time to graduation, and then entering the labor market. The value of this research, specifically a cost-benefit analysis to examine recent trends in local wages, tuition fees, defaults rates, poverty, and alignment with the local labor market, provides insight on the impact of local PE on the individual and the community, providing both educational and economic policy direction

Intrinsic hole mobility and trapping in a regio-regular poly(thiophene)

The transport properties of high-performance thin-film transistors (TFT) made with a regio-regular poly(thiophene) semiconductor (PQT-12) are reported. The room-temperature field-effect mobility of the devices varied between 0.004 cm2/V s and 0.1 cm2/V s and was controlled through thermal processing of the material, which modified the structural order. The transport properties of TFTs were studied as a function of temperature. The field-effect mobility is thermally activated in all films at T<200 K and the activation energy depends on the charge density in the channel. The experimental data is compared to theoretical models for transport, and we argue that a model based on the existence of a mobility edge and an exponential distribution of traps provides the best interpretation of the data. The differences in room-temperature mobility are attributed to different widths of the shallow localized state distribution at the edge of the valence band due to structural disorder in the film. The free carrier mobility of the mobile states in the ordered regions of the film is the same in all structural modifications and is estimated to be between 1 and 4 cm2/V s.Comment: 20 pages, 8 figure

Recombination in polymer-fullerene bulk heterojunction solar cells

Recombination of photogenerated charge carriers in polymer bulk heterojunction (BHJ) solar cells reduces the short circuit current (Jsc) and the fill factor (FF). Identifying the mechanism of recombination is, therefore, fundamentally important for increasing the power conversion efficiency. Light intensity and temperature dependent current-voltage measurements on polymer BHJ cells made from a variety of different semiconducting polymers and fullerenes show that the recombination kinetics are voltage dependent and evolve from first order recombination at short circuit to bimolecular recombination at open circuit as a result of increasing the voltage-dependent charge carrier density in the cell. The "missing 0.3V" inferred from comparison of the band gaps of the bulk heterojunction materials and the measured open circuit voltage at room temperature results from the temperature dependence of the quasi-Fermi-levels in the polymer and fullerene domains - a conclusion based upon the fundamental statistics of Fermions.Comment: Accepted for publication in Physical Review B. http://prb.aps.org/accepted/B/6b07cO3aHe71bd1b149e1425e58bf2868cda2384d?ajax=1&height=500&width=50

Training and orthotic effects related to functional electrical stimulation of the peroneal nerve in stroke.

OBJECTIVE: To examine the evidence for a training effect on the lower limb of functional electrical stimulation. DESIGN: Cohort study. PATIENTS: A total of 133 patients >6 months post-stroke. METHODS: Training and orthotic effects were determined from walking speed over 10 m, associated minimal and substantial clinically important differences (i.e. >0.05 and >0.10 m/s), and Functional Ambulation Category (FAC), ranging from household walking to independent walking in the community. RESULTS: An overall significant (p < 0.01) training effect was found that was not a clinically important difference (0.02 m/s); however, "community" FAC (≥ 0.8 m/s) and "most limited community walkers" FAC (0.4-0.58 m/s), but not "household walkers" (< 0.4 m/s), benefitted from a clinically important difference. A highly significant (p< 0.001), substantial clinically important orthotic effect (0.10 m/s) was found. In terms of overall improvement of one or more FACs, 23% achieved this due to a training effect, compared with 43% due to an orthotic effect. CONCLUSION: The findings suggest that functional electrical stimulation provides a training effect in those who are less impaired. Further work, which optimizes the use of the device for restoration of function, rather than as an orthotic device, will provide greater clarity on the effectiveness of functional electrical stimulation for eliciting a training effect