3,533 research outputs found
Listening to MEMS: An acoustic vibrometer
new way to characterize vibrating MEMS devices is presented. Using an acoustic particle velocity sensor the coupled sound field is measured, which is a measure for the movement of the MEMS device. We present several possible applications of this measurement method. It can be used as a read-out system for a mass flow sensor, and for characterization of in- and out-of-plane movements of MEMS devices. The method is an interesting alternative to laser scanning vibrometry due to its small size and low complexity; furthermore, it allows the user to `listen' directly to MEMS devices
Ultrafast electron diffraction using an ultracold source
We present diffraction patterns from micron-sized areas of mono-crystalline
graphite obtained with an ultracold and ultrafast electron source. We show that
high spatial coherence is manifest in the visibility of the patterns even for
picosecond bunches of appreciable charge, enabled by the extremely low source
temperature (~ 10 K). For a larger, ~ 100 um spot size on the sample, spatial
coherence lengths > 10 nm result, sufficient to resolve diffraction patterns of
complex protein crystals. This makes the source ideal for ultrafast electron
diffraction of complex macromolecular structures such as membrane proteins, in
a regime unattainable by conventional photocathode sources. By further reducing
the source size, sub-um spot sizes on the sample become possible with spatial
coherence lengths exceeding 1 nm, enabling ultrafast nano-diffraction for
material science.Comment: 5 pages, 4 figure
A genome-wide investigation of the worldwide invader Sargassum muticum shows high success albeit (almost) no genetic diversity
Twenty years of genetic studies of marine invaders have shown that successful invaders are often characterized by native and introduced populations displaying similar levels of genetic diversity. This pattern is presumably due to high propagule pressure and repeated introductions. The opposite pattern is reported in this study of the brown seaweed, Sargassum muticum, an emblematic species for circumglobal invasions. Albeit demonstrating polymorphism in the native range, microsatellites failed to detect any genetic variation over 1,269 individuals sampled from 46 locations over the Pacific-Atlantic introduction range. Single-nucleotide polymorphisms (SNPs) obtained from ddRAD sequencing revealed some genetic variation, but confirmed severe founder events in both the Pacific and Atlantic introduction ranges. Our study thus exemplifies the need for extreme caution in interpreting neutral genetic diversity as a proxy for invasive potential. Our results confirm a previously hypothesized transoceanic secondary introduction from NE Pacific to Europe. However, the SNP panel unexpectedly revealed two additional distinct genetic origins of introductions. Also, conversely to scenarios based on historical records, southern rather than northern NE Pacific populations could have seeded most of the European populations. Finally, the most recently introduced populations showed the lowest selfing rates, suggesting higher levels of recombination might be beneficial at the early stage of the introduction process (i.e., facilitating evolutionary novelties), whereas uniparental reproduction might be favored later in sustainably established populations (i.e., sustaining local adaptation).Agence Nationale de la Recherche - ANR-10-BTBR-04; European Regional Development Fund; Fundacao para a Ciencia e a Tecnologia - SFRH/BPD/107878/2015, UID/Multi/04326/2016, UID/Multi/04326/2019; Brittany Region;info:eu-repo/semantics/publishedVersio
Інтернет-скрипт як новітній різновид спортивного репортажу
Стаття присвячена жанровим ознакам Інтернет-скриптів. Розкривається проблема термінологічної ідентифікації текстів електронного спортивного репортажу, з’ясовується співвідношення Інтернет-скрипта з жанровими ознаками традиційного радіо- і телерепортажу, вивчаються можливості використання в Інтернет-скриптах аудіо- та відеоряду, паравербальних засобів, а також аналізується проблема позиції коментатора у репортажі.Статья посвещена жанровым признакам Интернет-скриптов. Раскрываются проблемы терминологической идентификации текстов электронного спортивного репортажа, рассматривается соотношение Интернет-скрипта с жанровыми признаками традиционного радио- и телерепортажа, изучаются возможности использования в Интернет-скриптах аудио- и видеоряда, паравербальных средств, а также анализируется проблема позиции коментатора в репортаже.The article deals with the genre features of Internet-scripts. The focus is on the problems of the terminological identification of the texts of electronic sport reports, the correlation of Internetscripts with genre features of traditional radio- and TV-reports, the usage of nonverbal means and the means of audio and video signals in Internet-scripts. The position of a commentator in sport report is regarded
Characterization and comparison of bacterial communities of an invasive and two native Caribbean seagrass species sheds light on the possible influence of the microbiome on invasive mechanisms
Invasive plants, including marine macrophytes, are one of the most important threats to biodiversity by displacing native species and organisms depending on them. Invasion success is dependent on interactions among living organisms, but their study has been mostly limited to negative interactions while positive interactions are mostly underlooked.
Recent studies suggested that microorganisms associated with eukaryotic hosts may play a determinant role in the invasion process. Along with the knowledge of their structure, taxonomic composition, and potential functional profile, understanding how bacterial communities are associated with the invasive species and the threatened natives (species-specific/environmentally shaped/tissue-specific) can give us a holistic insight into the invasion mechanisms. Here, we aimed to compare the bacterial communities associated with leaves and roots of two native Caribbean seagrasses (Halodule wrightii and Thalassia testudinum) with those of the successful invader Halophila stipulacea, in the Caribbean island Curaçao, using 16S rRNA gene amplicon
sequencing and functional prediction. Invasive seagrass microbiomes were more diverse and included three times more species-specific core OTUs than the natives. Associated bacterial communities were seagrass-specific, with higher similarities between natives than between invasive and native seagrasses for both communities associated with leaves and roots, despite their strong tissue differentiation. However, with a higher
number of OTUs in common, the core community (i.e., OTUs occurring in at least 80% of the samples) of the native H. wrightii was more similar to that of the invader H. stipulacea than T. testudinum, which could reflect more similar essential needs (e.g., nutritional, adaptive, and physiological) between native and invasive, in contrast to the two natives that might share more environment-related OTUs. Relative to native seagrass species, the invasive H. stipulacea was enriched in halotolerant bacterial genera with plant growth-promoting properties (like Halomonas sp. and Lysinibacillus sp.) and other potential beneficial effects for hosts (e.g., heavy metal detoxifiers and quorum sensing inhibitors). Predicted functional profiles also revealed some advantageous traits on the invasive species such as detoxification pathways, protection against pathogens,
and stress tolerance. Despite the predictive nature of our findings concerning the functional potential of the bacteria, this investigation provides novel and important insights into native vs. invasive seagrasses microbiome. We demonstrated that the bacterial community associated with the invasive seagrass H. stipulacea is different from native seagrasses, including some potentially beneficial bacteria, suggesting the
importance of considering the microbiome dynamics as a possible and important influencing factor in the colonization of non-indigenous species. We suggest further comparison of H. stipulacea microbiome from its native range with that from both the Mediterranean and Caribbean habitats where this species has a contrasting invasion success. Also, our new findings open doors to a more in-depth investigation combining
meta-omics with bacterial manipulation experiments in order to confirm any functional advantage in the microbiome of this invasive seagrass.CEECINST/00114/2018info:eu-repo/semantics/publishedVersio
A Multi Criteria Decision Analytic (MCDA) approach to combining evidence and patient preferences for cancer prevention and treatment: an application to prostate cancer screening
A 72-year-old man, edentulous in the maxilla for 20 years, presented himself at his dentist in 2006 with complaints concerning retention of his upper denture. The placement of implants was only possible if bone augmentation was undertaken; this was definitively rejected by the man. As an alternative, Muchor anchors were placed, but these did not provide an adequate solution to the retention problem. In the end, 2 palatal implants were placed, with magnetic anchoring. One year later, the man was very satisfied with this solution
Scalar leptoquark production at TESLA and CLIC based e-gamma colliders
We study scalar leptoquark production at TESLA and CLIC based e-gamma
colliders. Both direct and resolved contributions to the cross section are
examined. We find that the masses of scalar leptoquarks can be probed up to
about 0.9 TeV at TESLA and 2.6 TeV at CLIC.Comment: Misprints in equations are corrected. A careful spell check has been
done.17 pages, 8 figure
PMD5 VALUATION OF NEW DRUG APPLICATIONS OF PHARMACEUTICAL COMPANIES USING COMPOUND OPTION MODELS
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