Data summary and computer program for axial-flow pump rotor performance

Assembly of noncavitating blade element performance data for axial-flow pump rotor configurations has been collected and organized. Program facilitates handling large amounts of experimental data involved and may be used as data reduction program to process flow and performance measurements from other axial-flow pump configurations

An Experimental Scanning Capacitance Microscope

A fine needle stylus mounted to a three-dimensional piezo system is scanned across the sample in x-and y-direction, while a constant spacing between tip and sample, i.e., constant tip-to-sample capacitance, is maintained in z-direction. This is accomplished by vibrating the tip in z-direction at 1 kHz by typically 0.1 microns and by detecting the capacitance modulation from the shifting of the resonance of a tuned 1 GHz line. The horizontal resolution achieved so far is limited by the tip radius at about 200 nm and the vertical resolution is about 5 nm. The theoretical limits for finer tips are 7 nm and 1 nm for horizontal and vertical resolution, respectively

Associations between cardiorespiratory fitness and the metabolic syndrome in British men

Background Age and body mass index (BMI) are positively associated with the development of the metabolic syndrome (MetS). Cardiorespiratory fitness (CRF) can attenuate BMI-related increases in prevalence of MetS, but the nature of this association across different age strata has not been fully investigated. Aim To identify the association between CRF and MetS prevalence across age strata (20–69 years) and determine whether associations are independent of BMI. Methods CRF was estimated from incremental treadmill exercise in British men attending preventative health screening. Participants were placed in four age strata (20–39, 40–49, 50–59 and 60–69 years) and classified as fit or unfit using age-related cut-offs. The presence of MetS was defined using the National Cholesterol Education Program Adult Treatment Panel III criteria. Results 9666 asymptomatic men (48.7±8.4 years) were enrolled. The prevalence of MetS was 25.5% in all men and ranged from 17.1% in those aged 20–39 years to 30.6% in those aged 60–69 years. Fit men's likelihood of meeting the criteria for MetS was half (OR=0.51, 95% CI 0.46 to 0.57) that of unfit men. The likelihood of MetS was 32–53% lower across age strata in fit, compared with unfit men. Adjustment for BMI attenuated the association, though it remained significant in men aged 20–49 years. Conclusions The cardiometabolic benefits of CRF are independent of BMI particularly in men <50 years. Public health messages should emphasise the important role of CRF alongside weight management for enhancing cardiometabolic health

Intensity of Brillouin light scattering from spin waves in magnetic multilayers with noncollinear spin configurations: Theory and experiment

The scattering of photons from spin waves (Brillouin light scattering -- BLS) is a well-established technique for the study of layered magnetic systems. The information about the magnetic state and properties of the sample is contained in the frequency position, width, and intensity of the BLS peaks. Previously [Phys. Rev. B 67, 184404 (2003)], we have shown that spin wave frequencies can be conveniently calculated within the ultrathin film approach, treating the intralayer exchange as an effective bilinear interlayer coupling between thin virtual sheets of the ferromagnetic layers. Here we give the consequent extension of this approach to the calculation of the Brillouin light scattering (BLS) peak intensities. Given the very close relation of the BLS cross-section to the magneto-optic Kerr effect (MOKE), the depth-resolved longitudinal and polar MOKE coefficients calculated numerically via the usual magneto-optic formalism can be employed in combination with the spin wave precessional amplitudes to calculate full BLS spectra for a given magnetic system. This approach allows an easy calculation of BLS intensities even for noncollinear spin configurations including the exchange modes. The formalism is applied to a Fe/Cr/Fe/Ag/Fe trilayer system with one antiferromagnetically coupling spacer (Cr). Good agreement with the experimental spectra is found for a wide variety of spin configurations.Comment: 19 pages, 5 figure

Effects of exercise-based cardiac rehabilitation on cardiorespiratory fitness: A meta-analysis of UK studies

Background Exercise-based cardiac rehabilitation can promote meaningful improvements in cardiorespiratory fitness (fitness) but the magnitude of such improvements varies according to local characteristics of exercise programmes. We aimed to determine if cardiac rehabilitation (CR), as practised in the United Kingdom (UK), could promote meaningful changes in fitness and to identify programme characteristics which may moderate these changes. Methods Electronic and manual searches to identify UK CR studies reporting fitness at baseline and follow up. Change in fitness (Δfitness) was expressed as mean difference (95% CI) and effect size (ES). A random effects model was used to calculate the mean estimate for change in Δfitness. Between-group heterogeneity was quantified (Q) and investigated using planned sub-group analyses. Results We identified n = 11 studies containing 16 patient groups (n = 1 578) which used the incremental shuttle walking test (ISWT) (distance walked) to assess fitness. The overall mean estimate for Δfitness showed a significant increase in distance walked (ES = 0.48, P  12 exercise sessions compared with those receiving n ≤ 12 sessions. Conclusion We found significant increases in fitness (based on ISWT) in patients attending exercise-based CR in the UK. However, UK studies provide approximately one-third of the exercise “dose”, and produce gains in fitness less than half the magnitude reported in international studies

Brillouin scattering studies in Fe3_3O4_4 across the Verwey transition

Brillouin scattering studies have been carried out on high quality single crystals of Fe$_3$O$_4$ with [100] and [110] faces in the temperature range of 300 to 30 K. The room temperature spectrum shows a surface Rayleigh wave (SRW) mode at 8 GHz and a longitudinal acoustic (LA) mode at 60 GHz. The SRW mode frequency shows a minimum at the Verwey transition temperature $T_V$ of 123 K. The softening of the SRW mode frequency from about 250 K to $T_V$ can be quantitatively understood as a result of a decrease in the shear elastic constant C$_{44}$, arising from the coupling of shear strain to charge fluctuations. On the other hand, the LA mode frequency does not show any significant change around $T_V$, but shows a large change in its intensity. The latter shows a maximum at around 120 K in the cooling run and at 165 K in the heating run, exhibiting a large hysteresis of 45 K. This significant change in intensity may be related to the presence of stress-induced ordering of Fe$^{3+}$ and Fe$^{2+}$ at the octahedral sites, as well as to stress-induced domain wall motion.Comment: 14 pages, 3 figures, accepted in Physical Review B 200

Six-year changes in body mass index and cardiorespiratory fitness of English schoolchildren from an affluent area

We compared values of body mass index (BMI) and cardiorespiratory fitness (20 m shuttle-run test) of n=157 boys and n=150 girls aged 10-11 measured in 2014 with measures from 2008 and 1998. Boys' fitness was lower (d=0.68) in 2014 than 2008, despite a small (d=0.37) decline in BMI. Girl's BMI changed trivially (d=0.08) but cardiorespiratory fitness was lower (d=0.47) in 2014 than 2008. This study suggests fitness is declining at 0.95% per year, which exceeds the 0.8% rate of decline we reported between 1998 and 2008 and is double the global average of 0.43%. Declines in fitness were independent of changes in BMI suggesting continued reductions in English children's habitual physical activity levels

Simultaneous existence of two spin-wave modes in ultrathin Fe/GaAs(001) films studied by Brillouin Light Scattering: experiment and theory

A double-peaked structure was observed in the {\it in-situ} Brillouin Light Scattering (BLS) spectra of a 6 \AA$$ thick epitaxial Fe/GaAs(001) film for values of an external magnetic field $H$, applied along the hard in plane direction, lower than a critical value $H_c\simeq 0.9$ kOe. This experimental finding is theoretically interpreted in terms of a model which assumes a non-homogeneous magnetic ground state characterized by the presence of perperpendicular up/down stripe domains. For such a ground state, two spin-wave modes, namely an acoustic and an optic mode, can exist. Upon increasing the field the magnetization tilts in the film plane, and for $H \ge H_{c}$ the ground state is homogeneous, thus allowing the existence of just a single spin-wave mode. The frequencies of the two spin-wave modes were calculated and successfully compared with the experimental data. The field dependence of the intensities of the corresponding two peaks that are present in the BLS spectra was also estimated, providing further support to the above-mentioned interpretation.Comment: Shortened version (7 pages). Accepted for publication in Physical Review

Effect of Temperature on Plant Resistance to Arthropod Pests

Temperature has a strong influence on the development, survival, and fecundity of herbivorous arthropods, and it plays a key role in regulating the growth and development of their host plants. In addition, temperature affects the production of plant secondary chemicals as well as structural characteristics used for defense against herbivores. Thus, temperature has potentially important implications for host plant resistance. Because temperature directly impacts arthropod pests, both positively and negatively, distinguishing direct effects from indirect effects mediated through host plants poses a challenge for researchers and practitioners. A more comprehensive understanding of how temperature affects plant resistance specifically, and arthropod pests in general, would lead to better predictions of pest populations, and more effective use of plant resistance as a management tactic. Therefore, the goals of this paper are to 1) review and update knowledge about temperature effects on plant resistance, 2) evaluate alternative experimental approaches for separating direct from plant-mediated indirect effects of temperature on pests, including benefits and limitations of each approach, and 3) offer recommendations for future research