Pericyclic reactions in the synthesis of new 5-aryl-5,6-dihydroquinolino[2,1-b]quinazolin-12-ones

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Hydrothermal synthesis,thermal decomposition and optical properties of Fe2F5(H2O)(Htaz)(taz)(Hdma)

Crystal structure of Fe₂F₅(H₂O)(Htaz)(taz)(Hdma) which crystallizes in the triclinic system space group $\text{P}\overline{1}$ with unit cell parameters a = 8.8392(5) Å, b = 9.1948(5) Å, c = 9.5877(5) Å, α = 82.070(3)°, β = 63.699(3)°, γ = 89.202(3)°, Z = 2, and V = 690.91(7) ų, was synthesized under hydrothermal conditions at 393 K for 72 h, by a mixture of FeF₂/FeF₃, 1,2,4-triazole molecule (Htaz), and hydrofluoric acid solution (HF 4%) in dimethylformamide solvent (DMF). The main feature of this material is the coexistence of two oxidation states for iron atoms (Fe²⁺, Fe³⁺) in the unit cell, which associate by opposite fluorine corners of FeF₅N and FeF₂N₄ octahedra, and/or triazole molecule which originates the 2D produces material. The structure determination, performed from single crystal X-ray diffraction data, lead to the R₁/_WR₂ reliability factors 0.031/0.087. Thermal stability studies (TG/DTG/DTA) show that the decomposition provides in the temperature range 473–773 K and no mass loss was detected before 473 K. Mass spectrometry (MS) has been used. The optical absorption of the solid was measured at the corresponding λ_max using UV–vis diffuse-reflectance spectrum.     

Vocal Fatigue—Do Young Speech-Language Pathologists Practice What They Preach?

PurposeSpeech-Language Pathologists can be categorized as Level II professional voice users who play the roles of voice therapist or vocal coach to treat voice problems. SLPs may be at the risk of experiencing vocal fatigue due to vocal loading and other contributing factors. The present study was undertaken to find the percentage of SLPs reporting vocal fatigue, the probable factors resulting in vocal fatigue, the measures that are taken to avoid/reduce the occurrence of vocal fatigue, its effect on their professional and personal life and the measures taken to tackle it.ResultsThe results of this study are based on data collected from 142 SLPs and 50 controls using a questionnaire. 71.13% SLPs reported that they experience vocal fatigue. Some of the contributing factors that are mainly reported are long durations of voice use, voice use for recreational purposes, speaking loudly, frequent throat clearing, lack of adequate hydration and working in noisy or air-conditioned environments. The major symptoms reported were dryness in throat, tightness in neck and shoulder, choking sensation, effortful speech and pain in the throat. 59% SLPs reported that vocal fatigue affected their professional life while 44% SLPs reported that it affects their personal life also to varying degrees. Measures taken to avoid/ reduce the occurrence of vocal fatigue included vocal warm up, break in between sessions, and play activities. Only a few SLPs took intervention measures like ENT consultation, voice therapy, and home remedies.ConclusionSLPs are inevitably at high risk of experiencing vocal fatigue which, if left untreated, will lead to organic voice problems. However, many young SLPs who experience vocal fatigue reported vocal abuse, do not follow vocal hygiene program and do not follow evidence-based preventive or intervention practices to treat vocal fatigue.