The Theories of the Origin of the Antarctic Faunas and Floras

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Molecular spectroscopy in a solid-state device

The quantification of the electronic transport energy gap of a molecular semiconductor is essential for pursuing any challenge in molecular optoelectronics. However, this remains largely elusive because of the difficulties in its determination by conventional spectroscopic methods. This communication presents an in-device molecular spectroscopy (i-MOS) technique, which permits measuring this gap seamlessly, in real device operative conditions, at room temperature and without any previous knowledge of the material's parameters. This result is achieved by determining the occupied and unoccupied molecular orbitals of an organic semiconductor thin-film by using a single three terminal solid-state device

Tuning the charge flow between Marcus regimes in an organic thin-film device

Marcus’s theory of electron transfer, initially formulated six decades ago for redox reactionsin solution, is now of great importance for very diverse scientific communities. The molecularscale tunability of electronic properties renders organic semiconductor materials in principlean ideal platform to test this theory. However, the demonstration of charge transfer indifferent Marcus regions requires a precise control over the driving force acting on the chargecarriers. Here, we make use of a three-terminal hot-electron molecular transistor, which letsus access unconventional transport regimes. Thanks to the control of the injection energy ofhot carriers in the molecular thinfilm we induce an effective negative differential resistancestate that is a direct consequence of the Marcus Inverted Region

Diet-Independent Remodeling of Cellular Membranes Precedes Seasonally Changing Body Temperature in a Hibernator

Polyunsaturated fatty acids (PUFA) have a multitude of health effects. Their incorporation into membrane phospholipids (PL) is generally believed to depend directly on dietary influx. PL influence transmembrane protein activity and thus can compensate temperature effects; e.g. PL n-6 PUFA are thought to stabilize heart function at low body temperature (Tb), whereas long chain (>C18) n-3 PUFA may boost oxidative capacity. We found substantial remodeling of membranes in free-living alpine marmots which was largely independent of direct dietary supply. Organ PL n-6 PUFA and n-6 to n-3 ratios were highest at onset and end of hibernation after rapid increases during a brief transitional period prior to hibernation. In contrast, longer chain PL n-3 PUFA content was low at end of summer but maximal at end of hibernation. After termination of hibernation in spring, these changes in PL composition were rapidly reversed. Our results demonstrate selective trafficking of PUFA within the body, probably governed by a circannual endogenous rhythm, as hibernating marmots were in winter burrows isolated for seven months from food and external cues signaling the approaching spring. High concentrations of PL n-6 PUFA throughout hibernation are in line with their hypothesized function of boosting SERCA 2a activity at low Tb. Furthermore, we found increasing rate of rewarming from torpor during winter indicating increasing oxidative capacity that could be explained by the accumulation of long-chain PL n-3 PUFA. It may serve to minimize the time necessary for rewarming despite the increasing temperature range to be covered, because rewarming is a period of highest metabolic rate and hence production of reactive oxygen species. Considering the importance of PUFA for health our results may have important biomedical implications, as seasonal changes of Tb and associated remodeling of membranes are not restricted to hibernators but presumably common among endothermic organisms

A monograph of the Najades of Pennsylvania

Volume: 4Start Page: 279End Page: 34

Schizopod crustaceans in the U. S. National Museum. The families Lophogastridae and Eucopiidae

Volume: 31Start Page: 23End Page: 5

A Study of the Systematic and Geographic Distribution of the Decapod Family Crangonid\ue6 Bate

Volume: 47Start Page: 173End Page: 19

A monograph of the naiades of Pennsylvania. Part III. Systematic account of the genera and species

Volume: 8Start Page: 1End Page: 38