432 research outputs found
Noise, age and gender effects on speech intelligibility and sentence comprehension for 11- to 13-year-old children in real classrooms.
The present study aimed to investigate the effects of type of noise, age, and gender on children\u2019s speech intelligibility (SI) and sentence comprehension (SC). The experiment was conducted with 171 children between 11 and 13 years old in ecologically-valid conditions (collective presentation in real, reverberating classrooms). Two standardized tests were used to assess SI and SC. The two tasks were presented in three listening conditions: quiet; traffic noise; and classroom noise (non-intelligible noise with the same spectrum and temporal envelope of speech, plus typical classroom sound events). Both task performance accuracy and listening effort were considered in the analyses, the latter tracked by recording the response time (RT) using a single-task paradigm. Classroom noise was found to have the worst effect on both tasks (worsening task performance accuracy and slowing RTs), due to its spectro-temporal characteristics. A developmental effect was seen in the range of ages (11\u201313 years), which depended on the task and listening condition. Gender effects were also seen in both tasks, girls being more accurate and quicker to respond in most listening conditions. A significant interaction emerged between type of noise, age and task, indicating that classroom noise had a greater impact on RTs for SI than for SC. Overall, these results indicate that, for 11- to 13-year-old children, performance in SI and SC tasks is influenced by aspects relating to both the sound environment and the listener (age, gender). The presence of significant interactions between these factors and the type of task suggests that the acoustic conditions that guarantee optimal SI might not be equally adequate for SC. Our findings have implications for the development of standard requirements for the acoustic design of classrooms
The number of orderâpreserving maps of fences and crowns
PreprintWe perform an exact enumeration of the order-preserving maps of fences (zig-zags) and crowns (cycles). From this we derive asymptotic results.NSERCPreprin
Strigolactones affect phosphorus acquisition strategies in tomato plants
Strigolactones (SLs) are plant hormones that modulate morphological, physiological and biochemical changes as part of the acclimation strategies to phosphorus (P) deficiency, but an inâdepth description of their effects on tomato Pâacquisition strategies under P shortage is missing. Therefore, in this study, we investigate how SLs impact on root exudation and P uptake, in qualitative and quantitative terms over time, in wildâtype and SLâdepleted tomato plants grown with or without P. Under P shortage, SLâdepleted plants were unable to efficiently activate most mechanisms associated with the P starvation response (PSR), except for the upâregulation of P transporters and increased activity of Pâsolubilizing enzymes. The reduced SL biosynthesis had negative effects also under normal P provision, because plants overâactivated highâaffinity transporters and enzymatic activities (phytase, acidic phosphatase) to sustain elevated P uptake, at great carbon and nitrogen costs. A shift in the onset of PSR was also highlighted in these plants. We conclude that SLs are master kinetic regulators of the PSR in tomato and that their defective synthesis might lead both to suboptimal nutritional outcomes under P depletion and an unbalanced control of P uptake when P is available
Synthesis and anticancer activity of Pt(0)-olefin complexes bearing 1,3,5-triaza-7-phosphaadamantane and N-heterocyclic carbene ligands
A series of Pt(0)-η2-olefin complexes bearing 1,3,5-triaza-7-phosphaadamantane (PTA) or N-heterocyclic carbenes are prepared following different synthetic strategies depending on the nature of coordinated alkene and spectator ligands. These new platinum(0) derivatives have been tested in vitro as anticancer agents toward three different tumor (human ovarian cancer A2780 and A2780cis and K562 myelogenous leukemia) and one non-tumor (Hacat keratinocytes) cell lines, proving to be in several cases highly and selectively cytotoxic against ovarian cancer cells. Furthermore, this antiproliferative effect is associated with the activation of an apoptosis process. In particular, complexes equipped with PTA as spectator ligand give comparable IC50 values on A2780 (cisplatin sensitive) and A2780cis (cisplatin resistant) cell lines, indirectly proving that these new Pt(0) substrates act with a mechanism of action conceivably different from cisplatin. This hypothesis is also confirmed by the fact that our compounds, in contrast to cisplatin, are not able to promote erythroid-differentiation activity on the K562 myelogenous leukemia cell line
Parental evaluation of a telemonitoring service for children with Type 1 Diabetes
Introduction In the past years, we developed a telemonitoring service for young patients affected by Type 1 Diabetes. That service provides data to the clinical staff and offers an important tool to the parents, that are able to oversee in real time their children. The aim of this work was to analyze the parents' perceived usefulness of the service. Methods The service was tested by the parents of 31 children enrolled in a seven-day clinical trial during a summer camp. To study the parents' perception we proposed and analyzed two questionnaires. A baseline questionnaire focused on the daily management and implications of their children's diabetes, while a post-study one measured the perceived benefits of telemonitoring. Questionnaires also included free text comment spaces. Results Analysis of the baseline questionnaires underlined the parents' suffering and fatigue: 51% of total responses showed a negative tendency and the mean value of the perceived quality of life was 64.13 in a 0-100 scale. In the post-study questionnaires about half of the parents believed in a possible improvement adopting telemonitoring. Moreover, the foreseen improvement in quality of life was significant, increasing from 64.13 to 78.39 ( p-value\u2009=\u20090.0001). The analysis of free text comments highlighted an improvement in mood, and parents' commitment was also proved by their willingness to pay for the service (median\u2009=\u2009200\u2009euro/year). Discussion A high number of parents appreciated the telemonitoring service and were confident that it could improve communication with physicians as well as the family's own peace of mind
Lipophilicity of amyloid β-peptide 12-28 and 25-35 to unravel their ability to promote hydrophobic and electrostatic interactions
The potential of the synthetic strigolactone analogue GR24 for the maintenance of photosynthesis and yield in winter wheat under drought: Investigations on the mechanisms of action and delivery modes
Palladium(II)-η3-Allyl Complexes Bearing N-Trifluoromethyl N-Heterocyclic Carbenes: A New Generation of Anticancer Agents that Restrain the Growth of High-Grade Serous Ovarian Cancer Tumoroids
The first palladium organometallic compounds bearing N-trifluoromethyl N-heterocyclic carbenes have been synthesized. These η3-allyl complexes are potent antiproliferative agents against different cancer lines (for the most part, IC50 values fall in the range 0.02â0.5 ÎŒm). By choosing 1,3,5-triaza-7-phosphaadamantane (PTA) as co-ligand, we can improve the selectivity toward tumor cells, whereas the introduction of 2-methyl substituents generally reduces the antitumor activity slightly. A series of biochemical assays, aimed at defining the cellular targets of these palladium complexes, has shown that mitochondria are damaged before DNA, thus revealing a behavior substantially different from that of cisplatin and its derivatives. We assume that the specific mechanism of action of these organometallic compounds involves nucleophilic attack on the η3-allyl fragment. The effectiveness of a representative complex, 4 c, was verified on ovarian cancer tumoroids derived from patients. The results are promising: unlike carboplatin, our compound turned out to be very active and showed a low toxicity toward normal liver organoids
Plasma Sphingoid Base Profiles of Patients Diagnosed with Intrinsic or Idiosyncratic Drug-induced Liver Injury
Sphingolipids are exceptionally diverse, comprising hundreds of unique species. The bulk of circulating sphingolipids are synthesized in the liver, thereby plasma sphingolipid profiles represent reliable surrogates of hepatic sphingolipid metabolism and content. As changes in plasma sphingolipid content have been associated to exposure to drugs inducing hepatotoxicity both in vitro and in rodents, in the present study the translatability of the preclinical data was assessed by analyzing the plasma of patients with suspected drug-induced liver injury (DILI) and control subjects. DILI patients, whether intrinsic or idiosyncratic cases, had no alterations in total sphingoid base levels and profile composition compared to controls, whereby cardiovascular disease (CVD) was a confounding factor. Upon exclusion of CVD individuals, elevation of 1-deoxysphingosine (1-deoxySO) in the DILI group emerged. Notably, 1-deoxySO values did not correlate with ALT values. While 1-deoxySO was elevated in all DILI cases, only intrinsic DILI cases concomitantly displayed reduction of select shorter chain sphingoid bases. Significant perturbation of the sphingolipid metabolism observed in this small exploratory clinical study is discussed and put into context, in the consideration that sphingolipids might contribute to the onset and progression of DILI, and that circulating sphingoid bases may function as mechanistic markers to study DILI pathophysiology
Strigolactones as broad-spectrum antivirals against Ă-coronaviruses through targeting the main protease Mpro
- âŠ