Frequency-division-multiplex-based quantum efficiency determination of solar cells

Quantum efficiency (QE) is an important measurand that contains extensive information about the electrical and optical properties of photovoltaic devices. During device characterization, the measurement is, therefore, mandatory and necessary for, e.g., spectral mismatch correction of subsequent examinations. In this paper, a new real-time characterization method is presented, which allows accelerating QE measurements by a factor of more than 500 times without significantly degrading measurement accuracy, optical bandwidth, and resolution. The increased measurement speed is achieved by a frequency-division multiplexing approach using a spatial light modulating element, which allows it to illuminate the cell under test simultaneously with all wavelengths of interest. Feasibility and reproducibility are demonstrated in experimental measurements and validated by comparison with Fraunhofer ISE CalLab instruments

The morphology and evolution of the female postabdomen of Holometabola (Insecta)

In the present article homology issues, character evolution and phylogenetic implications related to the female postabdomen of the holometabolan insects are discussed, based on an earlier analysis of a comprehensive morphological data set. Hymenoptera, the sistergroup of the remaining Holometabola, are the only group where the females have retained a fully developed primary ovipositor of the lepismatid type. There are no characters of the female abdomen supporting a clade Coleopterida + Neuropterida. The invagination of the terminal segments is an autapomorphy of Coleoptera. The ovipositor is substantially modified in Raphidioptera and distinctly reduced in Megaloptera and Neuroptera. The entire female abdomen is extremely simplified in Strepsiptera. The postabdomen is tapering posteriorly in Mecopterida and retractile in a telescopic manner (oviscapt). The paired ventral sclerites of segments VIII and IX are preserved, but valvifers and valvulae are not distinguishable. In Amphiesmenoptera sclerotizations derived from the ventral appendages VIII are fused ventromedially, forming a solid plate, and the appendages IX are reduced. The terminal segments are fused and form a terminal unit which bears the genital opening subapically. The presence of two pairs of apophyses and the related protraction of the terminal unit by muscle force are additional autapomorphies, as is the fusion of the rectum with the posterior part of the genital chamber (cloaca). Antliophora are supported by the presence of a transverse muscle between the ventral sclerites of segment VIII. Secondary egg laying tubes have evolved independently within Boreidae (absent in Caurinus) and in Tipulomorpha. The loss of two muscle associated with the genital chamber are likely autapomorphies of Diptera. The secondary loss of the telescopic retractability of the postabdomen is one of many autapomorphies of Siphonaptera

Kombinierte Schwerhörigkeit bei Warfarin-Embryopathie - eine Fallvorstellung

Bei der seltenen Warfarin-Embryopathie können die betroffenen Kinder laut Literatur an einer Hörstörung leiden. Es handelte sich um einen 8 7/12 Jahre alten Jungen mit den typischen fazialen Stigmata sowie einer Brachytelephalangie. In der Anamnese besteht ein Zustand nach Sprachentwicklungsstörung bei geistiger Retardierung sowie rezidivierenden Schallleitungsschwerhörigkeiten beidseits, so dass bereits 3-malig eine Paukendrainageeinlage erfolgte. Des Weiteren liegt eine bekannte Marcumar-Einnahme der Mutter während der gesamten Schwangerschaft vor. Im Reintonaudiogramm ohne Vertäubung zeigte sich eine kombinierte Schwerhörigkeit bis 60 dB cochleobasal mit Schallleitungsanteil von 10-30 dB bei unauffälliger Tympanometrie. Es konnten weder TEOAE noch DPOAE gemessen werden. Bei der Schwellen-BERA war die Welle V beidseits bis 30 dB nachweisbar. Im CT/MRT des Schädels war weder eine Innen- noch Mittelohrmissbildung sichtbar. Aus pädaudiologischer Sicht erfolgten zunächst Kontrolluntersuchungen. Die Pädiater leiteten eine Beschulung in einer Förderschule ein. Bei vorliegenden fazialen Stigmata sollte an das seltene Krankheitsbild der Warfarin-Embryopathie gedacht werden. Wir beschreiben erstmalig exakt die dabei aufgetretene Hörstörung

Hawkmoths evaluate scenting flowers with the tip of their proboscis

Pollination by insects is essential to many ecosystems. Previously, we have shown that floral scent is important to mediate pollen transfer between plants (Kessler et al., 2015). Yet, the mechanisms by which pollinators evaluate volatiles of single flowers remained unclear. Here, Nicotiana attenuata plants, in which floral volatiles have been genetically silenced and its hawkmoth pollinator, Manduca sexta, were used in semi-natural tent and wind-tunnel assays to explore the function of floral scent. We found that floral scent functions to increase the fitness of individual flowers not only by increasing detectability but also by enhancing the pollinator's foraging efforts. Combining proboscis choice tests with neurophysiological, anatomical and molecular analyses we show that this effect is governed by newly discovered olfactory neurons on the tip of the moth's proboscis. With the tip of their tongue, pollinators assess the advertisement of individual flowers, an ability essential for maintaining this important ecosystem service. DOI: http://dx.doi.org/10.7554/eLife.15039.00

Transcriptome surveys in silverfish suggest a multistep origin of the insect odorant receptor gene family

The insect odorant receptor (Or) gene family is among the largest multigene families in insect genomes, but its evolutionary origin and mode of expansion is still a matter of debate. We performed transcriptomic surveys of two wingless insect species, the silverfish Lepisma saccharina and Tricholepidion gertschi, and identified multiple Or gene family members in both species. A phylogenetic analysis suggests that the silverfish Ors do not fall into the clade comprised of more derived flying insect ligand-binding Ors, but, along with bristletail, firebrat and some mayfly Ors, are consistently resolved as a distinct set of genes that may constitute an evolutionary intermediate between gustatory receptors and the more derived Ors of flying insects. We propose to consider these “primitive Ors” separately from higher insect Ors until their cellular expression patterns and function are resolved and suggest a multistep evolutionary scenario ultimately leading to the highly sensitive, rapidly evolving and physiologically diverse Or gene family observed in higher insects

Variant ionotropic receptors are expressed in olfactory sensory neurons of coeloconic sensilla on the antenna of the desert locust (Schistocerca gregaria)

The behaviour of the desert locust, Schistocera gregaria, is largely directed by volatile olfactory cues. The relevant odorants are detected by specialized antennal sensory neurons which project their sensory dendrites into hair-like structures, the sensilla. Generally, the responsiveness of the antennal chemosensory cells is determined by specific receptors which may be either odorant receptors (ORs) or variant ionotropic receptors (IRs). Previously, we demonstrated that in locust the co-receptor for ORs (ORco) is only expressed in cells of sensilla basiconica and sensilla trichodea, suggesting that cells in sensilla coeloconica may express different types of chemosensory receptors. In this study, we have identified the genes of S. gregaria which encode homologues of co-receptors for the variant ionotropic receptors, the subtypes IR8a and IR25a. It was found that both subtypes, SgreIR8a and SgreIR25a, are expressed in the antennae of all five nymphal stages and in adults. Attempts to assign the relevant cell types by means of in situ hybridization revealed that SgreIR8a and SgreIR25a are expressed in cells of sensilla coeloconica. Double fluorescence in situ hybridization experiments disclosed that the two IR-subtypes are co-expressed in some cells of this sensillum type. Expression of SgreIR25a was also found in some of the sensilla chaetica, however, neither SgreIR25a nor SgreIR8a was found to be expressed in sensilla basiconica and sensilla trichodea. This observation was substantiated by the results of double FISH experiments demonstrating that cells expressing SgreIR8a or SgreIR25a do not express ORco. These results support the notion that the antenna of the desert locust employs two different populations of OSNs to sense odors; cells which express IRs in sensilla coeloconica and cells which express ORs in sensilla basiconica and sensilla trichodea