Linguistic contributions to speech-on-speech masking for native and non-native listeners: language familiarity and semantic content

This study examined whether speech-on-speech masking is sensitive to variation in the degree of similarity between the target and the masker speech. Three experiments investigated whether speech-in-speech recognition varies across different background speech languages (English vs Dutch) for both English and Dutch targets, as well as across variation in the semantic content of the background speech (meaningful vs semantically anomalous sentences), and across variation in listener status vis-a?-vis the target and masker languages (native, non-native, or unfamiliar). The results showed that the more similar the target speech is to the masker speech (e.g., same vs different language, same vs different levels of semantic content), the greater the interference on speech recognition accuracy. Moreover, the listener's knowledge of the target and the background language modulate the size of the release from masking. These factors had an especially strong effect on masking effectiveness in highly unfavorable listening conditions. Overall this research provided evidence that that the degree of target-masker similarity plays a significant role in speech-in-speech recognition. The results also give insight into how listeners assign their resources differently depending on whether they are listening to their first or second language.     

Persicamidines—Unprecedented Sesquarterpenoids with Potent Antiviral Bioactivity against Coronaviruses

A new family of highly unusual sesquarterpenoids (persicamidines A–E) exhibiting significant antiviral activity was isolated from a newly discovered actinobacterial strain, Kibdelosporangium persicum sp. nov., collected from a hot desert in Iran. Extensive NMR analysis unraveled a hexacyclic terpenoid molecule with a modified sugar moiety on one side and a highly unusual isourea moiety fused to the terpenoid structure. The structures of the five analogues differed only in the aminoalkyl side chain attached to the isourea moiety. Persicamidines A–E showed potent activity against hCoV-229E and SARS-CoV-2 viruses in the nanomolar range together with very good selectivity indices, making persicamidines promising as starting points for drug development.     

Cargo Encapsulation in Photochromic Supramolecular Hydrogels Depends on Specific Guest-Gelator Supramolecular Interactions

Photochromic supramolecular hydrogels are prospective materials for light-triggered drug release and bionanotechnology. Here we present a structural analysis of peptide-derived photochromic supramolecular hydrogels, which were physically loaded with a selection of biologically related compounds, using advanced techniques of nuclear magnetic resonance. The results enable detailed and correct understanding of the loading process and will allow for correct design of pharmacologically relevant systems for phototriggered drug delivery.     

Controlled radical polymerization in the presence of N‐oxyls

Recent development in controlled radical polymerization has provided a tool to combine a relatively robust radical polymerization technique with structural control. This contribution focuses on stable free radical polymerization in the presence of nitroxides. The influence of 2,2,6,6‐tetramethyl‐piperidine‐N‐oxyl (TEMPO) and temperature on the copolymerization of styrene and acrylonitrile will be discussed. In the second part a new class of nitroxide stable free radicals will be presented that shows enhanced performance in styrene polymerizations.     

NO Reactions Inside Crystals

Reactions of chemisorbed reagents inside the crystalline molecular solid state are rare but offer unexploited methods for selective solvent-free chemical synthesis. Here we show that the greenhouse gas precursor, nitric oxide (NO) is chemisorbed by crystals of the hexafluorophosphate salts of complexes containing dicobalt sites. On NO sorption a cascade of reactions results in the in-crystal synthesis of nitrite and other gaseous NO_x. Recrystallization enabled structural elucidation of the mixed valent {[(bpbp)Co₂(μ-(η¹-O : η¹-N)-ONO)]₂(bdc)}⁴⁺ (bpbp=2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato, bdc=1,4-benzenedicarboxylato) cation. Overlapping signals in the solid-state EPR spectra confirm the Co^IICo^III oxidation state and the presence of NO₂ trapped inside the unrecrystallised solid products (br. g=4, triplet g=2 (340 mT), A(N)=73 MHz), despite three cycles of vacuum and N₂ flushing. Consistently, ν_N−O bands appear in the Raman and IR spectra that are due to the coordinated nitrate and the trapped NO₂ that were synthesized in-crystal. The latter is expelled by heating the solid to 160 °C or by recrystallization. Dimetallic cooperativity is proposed for the NO transformations in these rare examples of selective, chemisorptive substrate reactions in the solid-state.