A fossil byblidaceae seed from eocene South Australia

Copyright © 2004 by The University of ChicagoA single mummified angiosperm seed is described from a middle Eocene clay lens deposit at the Monier East Yatala Sand Pit, Golden Grove, South Australia. The seed is small (0.7 mm long and 0.45 mm wide), elliptical, black, and shows complex raised reticulate honeycomb sculpturing with deeply excavated cell floors and verrucate sculpturing on the anticlinal ridges. The fossil was compared against extant species of Byblis and the Droseraceae, especially the Drosera indica L. complex, common annual carnivorous plants that grow in seasonally damp environments in northern Australia and that have similarly small sculptured seeds. The combination of deep reticulately honeycombed cells and the verrucate anticlinal walls places the seed close to extant taxa in the Byblis liniflora Salisb. complex. However, in the absence of a larger sample and/or of definitive features to assign the fossil unequivocally to an extant species, as well as nomenclatural restrictions preventing the typification of a fossil by an illustration, the specimen is described as a parataxon and placed in Byblidaceae but without a formal name.Conran, John G., and David C. Christophe

Leveling the Playing Field: Disability, Title IX, and High School Sports

The Americans with Disabilities Act requires that covered entities provide a substantially equivalent experience to that of able-bodied persons. However, the Seventh Circuit, recently applied a but for test for a para-ambulatory high school athlete’s reasonable accommodation request, and denied this request. This Note argues that the Seventh Circuit should have used a two-part meaningful access test, which should be informed by past legislation based on discrimination as a result of physiological differences. To ensure that para-ambulatory student athletes have the opportunity to participate in high school sports, a separate division or qualifying times must be created

The Importance of Usability for Learning with Digital Media

Im Rahmen einer quantitativen Feldstudie wurde der Zusammenhang zwischen der System Usability eines digitalen Lernmediums und dem erzielten Lernerfolg in einem computerbasierten Unterrichtssetting untersucht. 31 Schülerinnen und Schüler zweier gymnasialer Biologie-Leistungskurse absolvierten dazu eine webbasierte Lerneinheit zu einem Thema der Zellbiologie. Es zeigte sich eine mittlere Korrelation zwischen der Usabilitybewertung und dem Ergebnis eines Leistungstests (r(28) = .384, p < .05). Der Zusammenhang erwies sich auch unter Kontrolle lernerfolgsrelevanter Personenmerkmale mittels multipler Regression als stabil. Gemeinsam erklären Vorwissen, numerische Verarbeitungskapazität, Aktualmotivation und System Usability 52.9% der beobachteten Leistungstestvarianz. Ferner zeigte sich ebenso eine mittlere Korrelation zwischen System Usability und dem Interesse der Schüler an der Lernaufgabe (r(28) = .396, p < .05). Usability erscheint damit als bedeutsames Interaktionsmerkmal für das Lernen mit digitalen Medien. In der durchgeführten Studie erklärte sie substantiell interindividuelle Unterschiede bei der computergestützten Wissensaneignung und stellt damit möglicherweise eine wesentliche Gelingensbedingung für die Digitalisierung des Lehrens und Lernens dar.In a field study we examined the relationship between the system usability of a digital learning medium and the learning success of computer-assisted instruction quantitatively. 31 students from two advanced biology courses at a German secondary school took a web-based lesson on cell biology. We found a medium correlation between subjective usability ratings and test scores (r(28) = .384, p < .05). The relationship remained stable even after controlling for personality traits and states relevant to learning success by using multiple regression. Prior knowledge, numerical reasoning, current motivation, and system usability accounted for 52.9% of the observed test score variance. Furthermore, we found a medium correlation between system usability and students interest in the learning task (r(28) = .396, p < .05). We therefore conclude that usability seems to be a significant attribute of interaction when students learn with digital media. The results of our study revealed that usability explained substantial individual differences in computer assisted knowledge acquisition and appears to be an essential success factor for the digital transformation of teaching and learning

Mise en ligne d'un microscope digitalisé et télécommandé

On décrit la mise en ligne avec un calculateur d'un microscope digitalisé en x, y, z, et télécommandé, pour les mesures dans l'émulsion ionographique

Extremizers of the JJ functional with respect to the d1d_1 metric

In previous work, Darvas-George-Smith obtained inequalities between the large scale asymptotic of the $J$ functional with respect to the $d_1$ metric on the space of toric K\"ahler metrics/rays. In this work we prove sharpness of these inequalities on all toric K\"ahler manifolds, and study the extremizing potentials/rays. On general K\"ahler manifolds we show that existence of radial extremizers is equivalent with the existence of plurisupported currents, as introduced and studied by McCleerey.Comment: Results from an REU project. arXiv admin note: text overlap with arXiv:2101.0258

View-Independent Working Memory Representations of Artificial Shapes in Prefrontal and Posterior Regions of the Human Brain

Traditional views of visual working memory postulate that memorized contents are stored in dorsolateral prefrontal cortex using an adaptive and flexible code. In contrast, recent studies proposed that contents are maintained by posterior brain areas using codes akin to perceptual representations. An important question is whether this reflects a difference in the level of abstraction between posterior and prefrontal representations. Here we investigated whether neural representations of visual working memory contents are view-independent, as indicated by rotation-invariance. Using fMRI and multivariate pattern analyses, we show that when subjects memorize complex shapes, both posterior and frontal brain regions maintain the memorized contents using a rotation-invariant code. Importantly, we found the representations in frontal cortex to be localized to the frontal eye fields rather than dorsolateral prefrontal cortices. Thus, our results give evidence for the view-independent storage of complex shapes in distributed representations across posterior and frontal brain regions

Understanding and Mitigating Tip Leakage and Endwall Losses in High Pressure Ratio Cores

Reducing endwall and tip secondary flow losses will be a key enabler for the next generation of commercial and military air transport and will be an improvement on the state-of-the-art in turbine loss reduction strategies. The objective of this research is three-fold: 1) To improve understanding of endwall secondary flow and tip clearance losses 2) To develop novel technologies to mitigate these losses and test them in low-speed cascade and rig environments 3) To validate predictive tools To accomplish these objectives, Pratt & Whitney (P&W) has teamed with Pennsylvania State University (PSU) to experimentally test new features designed by P&W. P&W will create new rim-cavity features to reduce secondary flow loss and improve purge flow cooling effectiveness and new blade tip features to manage leakage flows and reduce tip leakage secondary flow loss. P&W is currently developing technologies in these two areas that expect to be assimilated in the N+2/N+3 generation of commercial engines

PERANCANGAN DAN IMPLEMENTASI SISTEM KENDALI LAMPU PENERANGAN DENGAN METODE LOGIKA FUZZY

ABSTRAK Dewasa ini kebutuhan cahaya untuk penerangan aktivitas manusia dalam suatu ruang tertentu tak lepas dari pencahayaan oleh lampu listrik. Lampu listrik dalam kinerjanya pasti memanfaatkan energi listrik. Terkadang dalam kehidupan sehari-hari kita lalai dalam mengatur atau mematikan lampu yang menyala, meskipun pencahayaan di sekitar sudah cukup untuk menerangi aktivitas kita. Sehingga membuat energi listrik terbuang percuma begitu saja. Dengan melihat keadaan ini, maka dibuatlah suatu alat pengaturan intensitas cahaya agar kita tidak lagi repot untuk menyalakan dan mematikan lampu. Karena lampu akan hidup secara otomatis dan pencahayaan lampu juga dapat diatur secara otomatis, tergantung pada intensitas cahaya dan keberadaan manusia pada ruangan tersebut. Berdasarkan masalah tadi, maka penulis ingin menciptakan sebuah sistem pengontrolan intensitas cahaya menggunakan kamera untuk mendeteksi keberadaan manusia dalam suatu ruangan dan sensor LDR (Light Dependent Resistor) sebagai pendeteksi intensitas cahaya, yang nantinya bekerja secara terintegrasi untuk menghidupkan atau menyalakan lampu serta mengontrol intensitas pencahayaan lampu secara efektif dan efisien sehingga dapat menghemat energi. Secara keseluruhan, sistem ini bekerja dengan mendeteksi objek berupa keberadaan manusia dalam suatu ruangan. Pendeteksian objek manusia ini menggunakan sensor kamera yang kemudian dilakukan pengolahan terhadap citra yang dihasilkan oleh kamera tersebut untuk menentukan sistem pengontrolan aktif atau tidak. Ketika sistem aktif, sensor LDR berfungsi untuk mendeteksi besar intensitas cahaya dalam ruangan tersebut yang kemudian data tersebut diolah oleh mikrokontroler Raspberry Pi dengan metode fuzzy logic untuk menentukan kondisi driver relay. Kemudian driver relay menentukan besar intensitas pencahayaan lampu. Kata kunci : Lampu, Sensor LDR (Light Dependent Resistor), Kamera, Raspberry Pi, Fuzzy Logic, Cahay