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ABSTRACTThe concept of parental support in youth sport has been well studied, however, the measurement of the construct is not as advanced. Existing sport parenting literature has relied on study-designed instruments and/or psychometric instruments not developed or validated for use in the sport-specific context. The present multi-study research programme sought to develop and validate a theory-informed measure of parental support in youth sport. In study one, athletes’ perceptions of parental support were explored to gain an in-depth qualitative understanding of parental support. The findings from study one were subsequently utilised to inform the generation of initial scale items (70 items) which reflected parental support in study two. Content validity was then established during study two, through an expert panel of judges (n = 5) and members of the target population (n = 7). During study three, retained items (33 items) were administered to a sample of youth athletes (n = 318) for further item reduction and to explore the factor structure of the instrument, utilising exploratory factor analysis (EFA). In study four, a 19-item measure was administered to a second independent sample of youth athletes (n = 319), to confirm the factor structure of the instrument utilising confirmatory factor analysis (CFA). Following minor ad-hoc modifications, the final four-factor, 18-item YSPS-Q (autonomy; emotional; instrumental; informational support) demonstrated excellent model fit. Moreover, the 18-item YSPS-Q demonstrated good reliability, alongside convergent, and divergent validity. The YSPS-Q will enable researchers to effectively evaluate future parent-support programmes, and assist researchers in understanding what factors moderate its effectiveness.

The present study investigates the association between subjective wellness symptoms, and categorical point-of-care (POC) blood biomarkers of the free oxygen radical test (FORT), and systemic inflammation through high sensitivity C-reactive protein (Hs-CRP), in English Premier League footballers. Data from 38 male professional elite athletes (Mean Age = 25.8, SD = 4.4) from the English Premier League were included in the study, with a total of 674 individual testing records collected over an entire Premier League season. A player wellness questionnaire, along with fasted and rested point-of-care blood biomarker testing were collected weekly across the season. The wellness questionnaire collected subjective symptoms of illness and fatigue, while FORT and Hs-CRP were assessed through point-of-care analysis to highlight periods of excessive hydroperoxide production and systemic inflammation. Using a chi square goodness of fit model, results showed that there was a significant association between the frequency of symptoms logged and categorical POC blood biomarker data of FORT and HsCRP (P< 0.01). Of the records demonstrating normal levels of Hs-CRP and FORT concentrations, 27% logged symptoms with an average of 1.5 symptoms reported per answered record. Comparatively, excessive biomarker values demonstrated 55% of records having symptoms logged, averaging 2.4 symptoms reported per record.

ABSTRACTMany individuals are passionate for physical activity such as cycling, running, and soccer. Drawing from the dualistic model of passion, the purpose of the present study was to examine the direct and indirect relationships between passion (harmonious and obsessive) for physical activity, life satisfaction, performance, and innovativeness in organisational settings. Survey data were gathered from 272 cyclists who also occupied employment roles beyond their cycling pursuits. Data were analysed using structural equation modelling. Results indicated a direct positive relationship between harmonious passion and both performance and innovativeness at work. Moreover, results indicated that perceived life satisfaction indirectly influenced the relationships between harmonious passion and both performance and innovativeness at work. No significant relationships were found between obsessive passion for cycling and either organisational performance outcome. In sum, these findings suggest that passion for physical activity directly and indirectly (through life satisfaction) enhance organisational performance outcomes but only for harmonious passion.

High-quality single crystalline calcium fluoride (CaF2) has been of considerable practical concern as an optical lens to an excimer laser stepper in the deep-ultraviolet region due to its excellent transparency. Highly accurate thermophysical properties of molten CaF2are essential as input data for a numerical simulation of the crystal growth process. The density of molten CaF2has been successfully determined in the stable and undercooled liquid states (1600–1820 K) with an electrostatic levitator. The temperature dependence of the density of molten CaF2is given by $$\rho \hbox{/kg}\cdot \hbox{m}^{-3} = 3580-0.63T(\pm 1.6\% ).$$The coefficient of cubical expansion of molten CaF2has been determined to be $$\beta \hbox{/K}^{-\hbox{1}}=\frac{1}{5683-T}.$$High-quality single crystalline calcium fluoride (CaF2) has been of considerable practical concern as an optical lens to an excimer laser stepper in the deep-ultraviolet region due to its excellent transparency. Highly accurate thermophysical properties of molten CaF2are essential as input data for a numerical simulation of the crystal growth process. The density of molten CaF2has been successfully determined in the stable and undercooled liquid states (1600–1820 K) with an electrostatic levitator. The temperature dependence of the density of molten CaF2is given by $$\rho \hbox{/kg}\cdot \hbox{m}^{-3} = 3580-0.63T(\pm 1.6\% ).$$The coefficient of cubical expansion of molten CaF2has been determined to be $$\beta \hbox{/K}^{-\hbox{1}}=\frac{1}{5683-T}.$$

Abstract This paper reviews the past and present research and development activities in the field of electrostatic levitation at the Japan Aerospace Exploration Agency (JAXA). Particular emphasis is given on the important innovations of sub-millimeter sample handling, launch levitation initiation, aero-electrostatic hybrid levitation, multi-beam heating geometry, electrode design, and ultraviolet (UV) imaging. A summary of the thermophysical properties of refractory materials measured in their liquid states, above and below their melting point, as well as preliminary results of samples solidified from deep supercooled states are also reported.

Abstract Thermophysical properties of equilibrium and supercooled liquid iridium were measured using noncontact diagnostic techniques in an electrostatic levitator. Over the 2300–3000 K temperature range, the density can be expressed as ρ (T)=19.5×103 − 0.85(T− Tm) (kg·m−3) with Tm=2719 K. The volume expansion coefficient is given by 4.4 × 10−5 K−1. In addition, the surface tension can be expressed as γ (T)=2.23 × 103 − 0.17(T−Tm)(10−3N·m−1) over the 2373–2833 K span and the viscosity as η(T)=1.85 exp [3.0× 104/(RT)](10−3Pa·s) over the same temperature range.

The density, the isobaric heat capacity, the surface tension, and the viscosity of liquid rhodium were measured over wide temperature ranges, including the supercooled phase, using an electrostatic levitation furnace. Over the 1820 to 2250 K temperature span, the density can be expressed as ρ(T)=10.82×103−0.76(T−Tm) (kg⋅m−3) with Tm=2236 K, yielding a volume expansion coefficient α(T)=7.0×10−5(K−1). The isobaric heat capacity can be estimated as CP(T)=32.2+1.4×10−3(T−Tm) (J⋅mol−1⋅K−1) if the hemispherical total emissivity of the liquid remains constant at 0.18 over the 1820 to 2250 K interval. The enthalpy and entropy of fusion have also been measured, respectively, as 23.0 kJ⋅mol−1and 10.3 J⋅mol−1⋅K−1. In addition, the surface tension can be expressed as σ(T)=1.94×103−0.30(T−Tm) (mN⋅m−1) and the viscosity as η(T)=0.09 exp[6.4×104(RT)] (mPa⋅s) over the 1860 to 2380 K temperature range.

Here is reported a new scheme to accurately determine the vapor pressure of undercooled, liquid, and high temperature solid materials. The method relies on an imaging technique that measures the time variation of the radius of an electrostatically levitated sample. This scheme, compared to other techniques, offers unique opportunity to explore not only the liquid above the melting point but also the undercooled states of highly reactive materials in a contamination free environment. This was exemplified in this paper with titanium. For the first time, we report the vapor pressure $(V_{\rm p})$ of its liquid phase over a large temperature range, covering the undercooled region. Over the 1700 to 2050 K temperature range, it was measured as Log $V_{\rm p}(T) = 9.154 - 17978\ T^{-1}$ (3%). Similarly, for high temperature solid titanium, the vapor pressure could be expressed as Log $V_{\rm p}(T) = 16.634 - 32960\ T^{-1}$ (6%) over the 1770 to 1940 K temperature interval. From these data, the average latent heats of vaporization and sublimation were calculated respectively as 344.8 kJ/kg (8%) and 632.1 kJ/kg (6%) respectively.

Here is reported a new scheme to accurately determine the vapor pressure of undercooled, liquid, and high temperature solid materials. The method relies on an imaging technique that measures the time variation of the radius of an electrostatically levitated sample. This scheme, compared to other techniques, offers unique opportunity to explore not only the liquid above the melting point but also the undercooled states of highly reactive materials in a contamination free environment. This was exemplified in this paper with titanium. For the first time, we report the vapor pressure $(V_{\rm p})$of its liquid phase over a large temperature range, covering the undercooled region. Over the 1700 to 2050 K temperature range, it was measured as Log $V_{\rm p}(T) = 9.154 - 17978\ T^{-1}$(3%). Similarly, for high temperature solid titanium, the vapor pressure could be expressed as Log $V_{\rm p}(T) = 16.634 - 32960\ T^{-1}$(6%) over the 1770 to 1940 K temperature interval. From these data, the average latent heats of vaporization and sublimation were calculated respectively as 344.8 kJ/kg (8%) and 632.1 kJ/kg (6%) respectively.

Several thermophysical properties of hafnium-3 mass % zirconium, namely the density, the thermal expansion coefficient, the constant pressure heat capacity, the hemispherical total emissivity, the surface tension and the viscosity are reported. These properties were measured over wide temperature ranges, including overheated and undercooled states, using an electrostatic levitation furnace developed by the National Space Development Agency of Japan. Over the 2220 to 2875 K temperature span, the density of the liquid can be expressed as ρL(T)=1.20×104−0.44(T−Tm) (kg⋅m−3) with Tm=2504 K, yielding a volume expansion coefficient αL(T)=3.7×10−5(K−1). Similarly, over the 1950 to 2500 K span, the density of the high temperature and undercooled solid β-phase can be fitted as ρS(T)=1.22×104−0.41(T−Tm), giving a volume expansion coefficient αS(T)=3.4×10−5. The constant pressure heat capacity of the liquid phase can be estimated as CPL(T)=33.47+7.92×10−4(T−Tm) (J⋅mol−1⋅K−1) if the hemispherical total emissivity of the liquid phase remains constant at 0.25 over the 2250 K to 2650 K temperature interval. Over the 1850 to 2500 K temperature span, the hemispherical total emissivity of the solid β-phase can be represented as εTS(T)=0.32+4.79×10−5(T−Tm). The latent heat of fusion has also been measured as 15.1 kJ⋅mol−1. In addition, the surface tension can be expressed as σ(T)=1.614×103−0.100(T−Tm) (mN⋅m−1) and the viscosity as h(T)=0.495 exp [48.65×103/(RT)] (mPa⋅s) over the 2220 to 2675 K temperature range.

The surface tension and viscosity of liquid niobium, zirconium, and titanium have been determined by the oscillation drop technique using a vacuum electrostatic levitation furnace. These properties are reported over wide temperature ranges, covering both superheated and undercooled liquid. For niobium, the surface tension can be expressed as σ(T)=1.937×103−0.199(T−Tm) (mN·m−1) with Tm=2742 K and the viscosity as η(T)=4.50−5.62×10−3(T−Tm) (mPa·s), over the 2320 to 2915 K temperature range. Similarly, over the 1800 to 2400 K temperature range, the surface tension of zirconium is represented as σ(T)=1.500×103−0.111(T−Tm) (mN·m−1) and the viscosity as η(T)=4.74−4.97 ×10−3(T−Tm) (mPa·s) where Tm=2128 K. For titanium (Tm=1943 K), these properties can be expressed, respectively, as σ(T)=1.557×103−0.156(T−Tm) (mN·m−1) and η(T)=4.42−6.67×10−3(T−Tm) (mPa·s) over the temperature range of 1750 to 2050 K.

Four thermophysical properties of both solid and liquid molybdenum, namely, the density, the thermal expansion coefficient, the constant-pressure heat capacity, and the hemispherical total emissivity, are reported. These thermophysical properties were measured over a wide temperature range, including the undercooled state, using an electrostatic levitation furnace developed by the National Space Development Agency of Japan. Over the 2500 to 3000 K temperature span, the density of the liquid can be expressed as ρL(T)=9.10×103−0.60(T−Tm) (kg·m−3), with Tm=2896 K, yielding a volume expansion coefficient αL(T)=6.6×10−5(K−1). Similarly, over the 2170 to 2890 K temperature range, the density of the solid can be expressed as ρS(T)=9.49×103−0.50(T−Tm), giving a volume expansion coefficient αS(T)=5.3×10−5. The constant pressure heat capacity of the liquid phase could be estimated as CPL(T)=34.2+1.13×10−3(T−Tm) (J·mol−1·K−1) if the hemispherical total emissivity of the liquid phase remained constant at 0.21 over the temperature interval. Over the 2050 to 2890 K temperature span, the hemispherical total emissivity of the solid phase could be expressed as εTS(T)=0.29+9.86×10−5(T−Tm). The latent heat of fusion has also been measured as 33.6 kJ·mol−1.

Resistance to macrolides among group A streptococci is an increasing problem worldwide. We examined 496 strains phenotypically and genotypically for resistance to erythromycin and clindamycin. Strains were isolated in five different geographical areas representing about 45% of the total Quebec population. The overall resistance rate was 4.6% but varied from 0% in rural areas to 9.4% in Montreal. Of the 23 strains showing resistance to erythromycin, 15 (65%) had an identical pulsed-field gel electrophoresis pattern, were of serotype M28T28 and harboured the erm(TR) gene, suggesting the spread of a single clone. Of the remaining eight strains, two strains had the erm(B) gene, five had the mef gene and one with a different serotype also had the erm(TR) gene.

Forty-five depressed elderly patients were closely monitored in a research setting during treatment with nortriptyline and interpersonal psychotherapy for 7 consecutive months of acute and continuation treatment. Overall, nortriptyline was efficacious and well tolerated in this group. The frequency of somatic complaints measured by the Rating Scale for Side Effects declined by 50% during the acute phase of treatment, suggesting that many somatic complaints that may be attributed to side effects of nortriptyline are actually somatic symptoms of depression. The authors discuss the implications of these findings and offer practical advice for the treating clinician. (J Geriatr Psychiatry Neurol1991;4:226-230).

We report on the first observations, to our knowledge, of the ^4F_3/2?^4I_11/2 (1060-nm) induced fluorescence in a Nd-doped CaO–Al_2O_3 glass pumped by an 810-nm diode laser. This new doped glass is produced as a 3-mm-diameter sphere by heating and melting in an aerodynamic containerless trap and is rapidly solidified by radiative cooling (>350 K/s). This glass has an interesting Nd^3+ emission maximum at 1067 nm (not many doped glasses have their emission maxima close to 1067 nm). The measured fluorescence decay time of the ^4F_3/2 level is short (0.3 ms) when the ion is excited by a narrow-band pulsed dye laser.

Ninety-nine intravascular catheters were evaluated by a semiquantitative culture and Gram and acridine orange direct stains. A diagnosis of catheter-related infection was determined by a retrospective review of clinical records. Compared with the culture method, direct examination of catheters lacked sensitivity. Surprisingly, for some patients, a positive stain for yeasts not recovered by culture was considered significant. The culture correlated with bacteremia but failed to predict infection in 42% of patients.