Silver nanoparticles (AgNPs) exhibit a consistent amount of flexible properties which endorse them for a larger spectrum of applications in biomedicine and related fields. Over the years, silver nanoparticles have been subjected to numerous in vitro and in vivo tests to provide information about their toxic behavior towards living tissues and organisms. Researchers showed that AgNPs have high antimicrobial efficacy against many bacteria species including Escherichia coli, Neisseria gonorrhea, Chlamydia trachomatis and also viruses. Due to their novel properties, the incorporation of silver nanoparticles into different materials like textile fibers and wound dressings can extend their utility on the biomedical field while inhibiting infections and biofilm development. Among the noble metal nanoparticles, AgNPs present a series of features like simple synthesis routes, adequate and tunable morphology, and high surface to volume ratio, intracellular delivery system, a large plasmon field area recommending them as ideal biosensors, catalysts or photo-controlled delivery systems. In bioengineering, silver nanoparticles are considered potentially ideal gene delivery systems for tissue regeneration. The remote triggered detection and release of bioactive compounds of silver nanoparticles has proved their relevance also in forensic sciences. The authors report an up to date review related to the toxicity of AgNPs and their applications in antimicrobial activity and biosensors for gene therapy.
This study systematically investigates the temporal organization of American English onset and coda consonant clusters on the basis of kinematic data. Results from seven speakers suggest that consonants in complex onsets are organized globally with respect to the following vowel, while consonants in complex codas are organized locally relative to the preceding vowel. These results support the competitive coupling model hypothesized for complex onsets, a model according to which consonant gestures in onsets are each coupled in-phase to the vowel, and antiphase with each other. The results are overall also consistent with the noncompetitive coupling relations assumed for codas, by which only the first consonant in a cluster is coupled antiphase with the vowel, and any subsequent consonants are coupled antiphase to each other. However, our data also show that the segmental composition of the cluster affects the timing relationship in codas, particularly /lC/ coda clusters pattern differently from other clusters and do not adhere to the predicted timing relations. The data contribute to our understanding of the interaction of linguistic structure and motor control of the articulators in speech production.
The goal of this paper was the design, development, and characterization of some new composites, based on collagen and dextran as natural polymers and zinc oxide as antimicrobial, to be used in wound healing. Collagen hydrogels with various concentrations of dextran and zinc oxide were investigated in terms of rheological analysis. The spongious composites, obtained by freeze-drying of hydrogels, were evaluated by morphology (SEM), water uptake, and biological (enzymatic biodegradation) analysis. All the results were strongly influenced by the nature and concentration of composite components. Based on the performances of the hydrogels, stationary rheometry, porous structure, morphology, and biological behavior, the antimicrobial spongious composite based on collagen and dextran with 50% ZnO were the most promising for future applications in wound dressing and a biomaterial with high potential in skin regeneration.
An increasing number of studies has linked certain types of articulatory or acoustic variability with speech errors, but no study has yet examined the relationship between such articulatory variability and acoustics. The present study aims to evaluate the acoustic properties of articulatorily errorful /k/ and /t/ stimuli to determine whether these errors are consistently reflected in the acoustics. The most frequent error observed in the articulatory data is the production of /k/ and /t/ with simultaneous tongue tip and tongue dorsum constrictions. Spectral analysis of these stimuli's bursts shows that /k/ and /t/ are differently affected by such co-production errors: co-production of tongue tip and tongue dorsum during intended /k/ results in typical /k/ spectra ͑and hence in tokens robustly classified as /k/͒, while co-productions during intended /t/ result in spectra with roughly equal prominence at both the mid-frequency ͑/k/-like͒ and high-frequency ͑/t/-like͒ ranges ͑and hence in tokens ambiguous between /k/ and /t/͒. This outcome is not due to an articulatory timing difference, but to tongue dorsum constriction having an overall greater effect on the acoustic than a tongue tip constriction when the two are co-produced.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.