Effects of HearFones on speaking and singing voice quality

HearFones (HF) have been designed to enhance auditory feedback during phonation. This study investigated the effects of HF (1) on sound perceivable by the subject, (2) on voice quality in reading and singing, and (3) on voice production in speech and singing at the same pitch and sound level.

Test 1: Text reading was recorded with two identical microphones in the ears of a subject. One ear was covered with HF, and the other was free. Four subjects attended this test. Tests 2 and 3: A reading sample was recorded from 13 subjects and a song from 12 subjects without and with HF on. Test 4: Six females repeated [pa:p:a] in speaking and singing modes without and with HF on same pitch and sound level.

Long-term average spectra were made (Tests 1–3), and formant frequencies, fundamental frequency, and sound level were measured (Tests 2 and 3). Subglottic pressure was estimated from oral pressure in [p], and simultaneously electroglottography (EGG) was registered during voicing on [a:] (Test 4). Voice quality in speech and singing was evaluated by three professional voice trainers (Tests 2–4).

HF seemed to enhance sound perceivable at the whole range studied (0–8 kHz), with the greatest enhancement (up to ca 25 dB) being at 1–3 kHz and at 4–7 kHz. The subjects tended to decrease loudness with HF (when sound level was not being monitored). In more than half of the cases, voice quality was evaluated “less strained” and “better controlled” with HF. When pitch and loudness were constant, no clear differences were heard but closed quotient of the EGG signal was higher and the signal more skewed, suggesting a better glottal closure and/or diminished activity of the thyroarytenoid muscle.     

Validation of the microbiological methods hygicult dipslide, contact plate, and swabbing in surface hygiene control: a Nordic collaborative study

A collaborative study on total aerobic bacterial count was conducted to validate the Hygicult TPC dipslide against contact plates and swabbing, using stainless-steel surfaces artificially contaminated with different microbes at various levels. Twelve laboratories took part in the validation procedure. The total number of collaborative samples was 108. The microbial level in each sample was assessed in triplicate using the 3 above-mentioned methods under 3 different incubation conditions (at 25 +/- 1 degrees C for 48 and 72 h and at 30 +/- 1 degrees C for 48 h). Surface sampling methods detached 25-30% at the lowest (theoretical yield, 1.4 cfu/cm2), 18-20% at the middle (theoretical yield, 10.7 cfu/cm2), and 16-21% at the highest (theoretical yield, 43.6 cfu/cm2) levels of microbes from the test surfaces. The percentage of acceptable results after removing outliers was 89%. Repeatability standard deviations ranged from 27.2 to 74.6% and reproducibility standard deviations ranged from 42.1 to 97.5%. There were no significant differences between results obtained at different incubation temperatures (25 and 30 degrees C) or incubation times (48 and 72 h) for all 3 methods. The Hygicult TPC dipslide, contact plate, and swabbing methods gave similar results at all 3 microbial levels tested: 0.35-0.43 cfu/cm2 at the lowest level, 1.9-2.2 cfu/cm2 at the middle level, and 7.1-9.1 cfu/cm2 at the highest level.     

On the Synthesis of Chloro Derivatives of Five-Membered Heterocyclics via the Lithium Derivatives

In connection with our ¹³C NMR investigations we were interested in obtaining pure samples of 2- and 3-chlorofuran and 2- and 3-chloroselenophene. While direct chlorination with molecular chlorine or other chlorinating agents can successfully be used for the preparation of 2-chlorothiophene,¹ we could not reproduce either yields or isomeric purity in the corresponding chlorination of selenophene.^2,3     

Sensitivity Analysis of Wave-equation Tomography: A Multi-scale Approach

Earthquakes, viewed as passive sources, or controlled sources, like explosions, excite seismic body waves in the earth. One detects these waves at seismic stations distributed over the earth’s surface. Wave-equation tomography is derived from cross correlating, at each station, data simulated in a reference model with the observed data, for a (large) set of seismic events. The times corresponding with the maxima of these cross correlations replace the notion of residual travel times used as data in traditional tomography. Using first-order perturbation, we develop an analysis of the mapping from a wavespeed contrast (between the “true” and reference models) to these maxima. We develop a construction using curvelets, while establishing a connection with the geodesic X-ray transform. We then introduce the adjoint mapping, which defines the imaging of wavespeed variations from “finite-frequency travel time” residuals. The key underlying component is the construction of the Fréchet derivative of the solution to the seismic Cauchy initial value problem in wavespeed models of limited smoothness. The construction developed in this paper essentially clarifies how a wavespeed model is probed by the method of wave-equation tomography.     

Robust portfolio modeling with incomplete cost information and project interdependencies

Robust portfolio modeling (RPM) [Liesiö, J., Mild, P., Salo, A., 2007. Preference programming for robust portfolio modeling and project selection. European Journal of Operational Research 181, 1488–1505] supports project portfolio selection in the presence of multiple evaluation criteria and incomplete information. In this paper, we extend RPM to account for project interdependencies, incomplete cost information and variable budget levels. These extensions lead to a multi-objective zero-one linear programming problem with interval-valued objective function coefficients for which all non-dominated solutions are determined by a tailored algorithm. The extended RPM framework permits more comprehensive modeling of portfolio problems and provides support for advanced benefit–cost analyses. It retains the key features of RPM by providing robust project and portfolio recommendations and by identifying projects on which further attention should be focused. The extended framework is illustrated with an example on product release planning.     

On the syntheses of 8-Heteroaryl-substituted 9-(β-D-Ribofuranosyl)-2,6-diaminopurines through Pd-catalyzed coupling in the presence of cupric oxide

Convenient methods for the preparation of 9-(β-D-ribofuranosyl) derivatives of 8-(2- and 3-thienyl)-2,6-diaminopurine and of 8-(2- and 3-furyl)-2,6-diaminopurine, which are potential antiviral agents has been worked out. The key step was a Pd(0)-catalyzed Stille coupling between 2- and 3-tributylstannylthiophene and 2- and 3-tributylstannylfuran and trimethylsilyl protected 9-(β-D-ribofuranosyl)-2,6-diamino-8-bro-mopurine. The use of N,N-dimethylformamide as solvent at 110° and dichloro(diphenylphosphine-propane)palladium(II) [PdC1₂(dppp)] with cupric oxide as co-reagent was essential in order to obtain a fast reaction and high yields.     

Synthesis, Properties, and Reactions of 5-Substituted Derivatives of 2,3-Diphenylquinoxaline [1]

Catalytic hydrogenation of 5-nitro-2,3-diphenylquinoxaline led to the corresponding amine which, in turn, afforded products of nucleophilic substitution on reaction with alkoxymethylene derivatives. Thermal cyclization of selected alkoxymethylene derivatives yielded substituted pyridoquinoxalines. The conditions for successful hydrolysis of ester, decarboxylation of the acid, following chlorination of pyridone and reductive removal of the chlorine atom from it to produce parental heterocycle 2,3-diphenyl-pyrido[2,3-f]quinoxaline were found. All of the tested products of the nucleophilic substitution showed no antibacterial activity.     

Effects of short- and long-term ultraviolet B irradiation on the immune system of the common carp (Cyprinus carpio)

Carp (Cyprinus carpio) were repeatedly exposed to 0, 60, 120 and 240 mJ/cm2 ultraviolet B (UVB) radiation three times in 1 week (short-term exposure) or 12 times in 4 weeks (long-term exposure). The effect of UVB on the functioning of the carp immune system was studied on day 2 after the final irradiation. After short-term UVB exposure, the whole-blood respiratory burst and cytotoxic activity were markedly enhanced, with parallel responses in both the number of circulating granulocytes and in the plasma cortisol concentration of the fish. These changes were not detectable after long-term exposure. The respiratory burst by head kidney granulocytes was suppressed dose dependently after both exposures, but cytotoxic activity was not affected. Exposure to UVB also modulated lymphocyte functions: nonstimulated and PHA-stimulated proliferation of head kidney lymphocytes in vitro was enhanced by both short-term and long-term exposure. LPS-stimulated proliferation was not affected by exposure nor was the number of immunoglobulin-secreting cells in the head kidney. In long-term exposure, the highest dose reduced the level of plasma IgM. This study indicates that UVB irradiation induces immunomodulation in the blood and head kidney of the carp and that the effects of short- and long-term exposure differ from each other. The results emphasize the potentially harmful impact of increased solar UVB radiation on fish immune functions.     

Introduction of Amino Alcohols in the Ring-Opening Reaction of 3-bromo-2,5-dimethylthiophene 1,1-dioxide. A short diastereoselective synthesis of substituted ‘tetrahydrobenzo[a]pyrrolizidines’ (= octahydro-1H-pyrrolo[2,1-a]isoindoles) using L-prolinol

Tetrahydrobenzo[a]pyrrolizidines (= octahydro-1H-pyrrolo[2,1-a]isoindoles) and tetrahydrobenzo[a]indo-lizidines, (= decahydropyrido[2,1-a]isoindoles) were prepared stereoselectively in four steps through an amineinduced ring-opening of 3-bromo-2,5-dimethylthiophene 1,1-dioxide ( 1 ) with L -prolinol ( 9 ), piperidine-2-methanol ( 10 ), and piperidine-2-ethanol ( 11 ), yielding the dienes (2S)-1-[(2E,4Z)-4-bromohexa-2,4-dienyl]pyrrolidine-2-methanol ( 12 ), 1-[(2E,4Z)-4-bromohexa-2,4-dienyl]piperidine-2-methanol ( 13 ), and 1-[(2E,4Z)-4-bromo-hexa-2,4-dienyl]piperidine-2-ethanol ( 14 ; Scheme2), which, after conversion into their α,β-unsaturated esters, cyclized in a TiCl₄-catalyzed intramolecular Diets-Alder reaction (Scheme3). A discussion on the mechanism of the ring opening reaction including semiempirical and ab initio calculations is also presented.