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In the bodybuilding and fitness communities, anecdotal evidence suggests that some take ‘steroid holidays’, traveling to and living in foreign countries so as to have greater access to performance ...

When used to pollinate flowers of diploid Actinidia chinensis ‘Hort16A’, pollen from tetraploid A. chinensis or hexaploid A. deliciosa males produced fruit with higher fresh weight than did pollen from a diploid A. chinensis male. The dry matter content of the fruit was also increased once differences in the dry matter content of the seed were taken into account. These increases occurred despite slightly delayed harvest maturity and fewer well-formed seed in fruit following pollination by the higher ploidy males. Variation in seed development following different pollen treatments could be explained largely by the genomic ratios expected in the endosperm, and the tendency of ‘Hort16A’ to produce a proportion of 2n gametes. The results suggest that, in contrast to many other diploid A. chinensis genotypes, pollination of ‘Hort16A’ by males of higher ploidy may be beneficial in terms of fresh fruit weight.

Flowers of diploid Actinidia chinensis (kiwifruit) were hand-pollinated with pollen from either hexaploid A. deliciosa or diploid A. chinensis males and the subsequent fruit were evaluated. Following pollination with A. deliciosa pollen, fruit set, fresh weight, dry matter content, and seed weight and number were reduced. However, the most striking effect was on fruit flesh colour: the proportion of seedlings expressing red pigmentation, the intensity of pigmentation and the anthocyanin concentration were greatly reduced. The effects on maternal fruit tissues were probably indirect consequences of a reduction in the number of fertilized ovules due to partial pollen incompatibility. Effects on seed development could be explained largely by the ploidy difference between the seed and pollen parents. Growers should be cautious about using A. deliciosa pollen to pollinate diploid A. chinensis females, especially red-fleshed cultivars.

The aim of this study was to compare the somersaulting techniques used in the 16 highest-scoring and 16 lowest-scoring Roche vaults. Our hypothesis was that the gymnasts performing the highest-scoring Roche vaults would demonstrate a better technique than those performing the lowest-scoring Roche vaults while on the horse (pushing off the horse more effectively), somersaulting (executing most of the required somersaults higher in flight), and landing (showing a greater control). A 16-mm motion picture camera, operating at 100 Hz, recorded the vaults during the official competition. The two-dimensional direct linear transformation was used for spatial reconstruction. The results of t-tests (P0.05) indicated that, compared with the low-scoring gymnasts, the high-scoring gymnasts had: (1) greater height of body centre of mass and a more fully extended body position at the horse take-off; (2) greater height of body centre of mass at the peak of post-flight, knee release, and touchdown on the mat; (3) greater horizontal and vertical displacements of body centre of mass, greater somersaulting rotation, and longer time from the knee release to mat touchdown; and (d) markedly smaller landing point deductions. In conclusion, a successful Roche vault is likely when the focus is on: (a) leaving the horse with a large vertical velocity in an extended body position to achieve a high trajectory of centre of mass by first extending the legs, then immediately pushing off the horse vigorously, using the muscles of the upper extremity; (b) grasping the knees immediately after the take-off from the horse, achieving the tightly tucked body position early during the ascent to the peak, and completing two-thirds of the required somersaults at a great height; (c) releasing the knees and extending the body above the top level of the horse; and (d) contacting the mat with a high body centre of mass position.

The 16 highest-scored Roche vaults (G1) performed during the 2000 Olympic Games were compared with those receiving the 16 lowest-scores (G2). A 16-mm motion picture camera operating at 100 Hz recorded the vaults during the competition. The results of t tests (p < .05) indicated G1, compared to G2, had (a) shorter time of board support, greater normalised average upward vertical force and backward horizontal force exerted by the board, greater change in the vertical velocity while on the board, and greater vertical velocity at board take-off, (b) comparable linear and angular motions in pre-flight, (c) smaller backward horizontal impulse exerted by the horse, smaller loss of the horizontal velocity while on the horse, and greater horizontal and vertical velocities at horse take-off, (d) greater height and larger horizontal distance of post-flight, (e) higher body mass centre at knee release, and (f) higher mass centre, greater normalised moment of inertia, and smaller vertical velocity at mat touchdown. Therefore, gymnasts and coaches should focus on sprinting the approach; blocking and pushing-off the take-off board rapidly and vigorously; departing the board with a large vertical velocity; exerting large downward vertical force and small forward horizontal force from the hand-stand position while on the horse; departing the horse with large horizontal and vertical velocities; and completing the majority of the double salto forward near the peak of trajectory and releasing the knees above the top of the horse to prepare for a controlled landing.

The study forms the first part of the development of an immunoassay to detect storage mite infestations in cereals and their derived products. This was achieved by examining the suitability of an existing monoclonal antibody (MAb) raised against the cosmopolitan food mite, Lepidoglyphus destructor (Schrank). The results demonstrate that in the absence of grain the MAb could detect and quantify unknown numbers of L. destructor, ranging between 0 and 100 adult mites. However, in the presence of grain the sensitivity of the assay decreased. This was probably because the existing antibody had not been raised for this purpose. To overcome this, an additional polyclonal antibody was used which gave satisfactory detection of 0 to 100 adult mites seeded in 5 g of grain. The work has shown the excellent potential of an immunoassay method for the rapid detection of storage mites in unmilled cereals.

Twenty-six subjects were selected from 25 American and 28 Japanese gymnasts filmed during their respective 1990 national championships. The 13 highest (Group 1) and 13 lowest (Group 2) scored basket-to-handstand mounts on the parallel bars were compared. It was hypothesized that there would be significant differences between the kinematics demonstrated by the gymnasts from the two groups and that differences in the early preparatory phases would account for most of the differences in the resulting movements. The results revealed significant differences (P0.005) between the two groups, with Group 1 achieving greater vertical displacement of the centre of mass during the upward inverted swing and larger vertical velocity at bar release; greater backward horizontal motion of the centre of mass and forward body rotation in the flight phase; and a higher body centre of mass at bar regrasp with greater fluency of upward body motion into the handstand position. There were no significant differences between the two groups in the performance of the jump to end of backward swing and forward swing to maximum body pike that could be attributed to the differences in the last three phases. Based on the findings of this study, successful performance is likely when the arm pull is sustained with maximum effort until the body centre of mass and the trunk are well above the bars to enable the bar release with high body centre of mass, high body angle, large vertical velocity, backward horizontal velocity and forward angular momentum. This brings about (1) the desired direction of linear motion of centre of mass and (2) high body centre of mass and high body angle close to the handstand position at bar regrasp, which together ensure the fluency of upward body motion into the final position.

Charles Henry Gilbert (1859–1928) was a pioneering ichthyologist and an early fishery biologist of particular significance to the fisheries of the west coast of the U.S. As chairman of the Zoology Department of Leland Stanford Junior, University in Palo Alto, CA, from 1891 to 1925, Gilbert became increasingly interested in the biology of Pacific salmon (Oncorhynchus spp.). His studies of the use of scales to age salmon (ca. 1909 to 1912) led to his research on these fishes for the British Columbia Provincial Fisheries Department (1912 to 1924) and for the U.S. Bureau of Fisheries, mainly in Alaska, from about 1917 to 1927. He pioneered racial studies on salmon using the scale method, was instrumental in establishing sound tagging programs on salmon in Alaska to define their migratory patterns, and was one of the very first scientists to consider the population dynamics of northwest stocks of Pacific salmon. Above all, Gilbert was an ardent conservationist who warned both the salmon‐canning indust...

Bacteriophage T7 RNA polymerase and derivatives that contain the nuclear localization signal (NLS) from simian virus 40 T antigen (J. J. Dunn, B. Krippl, K. Bernstein, H. Westphal, and F. W. Studier, Gene 68:259-266, 1988) were expressed in Saccharomyces cerevisiae under the control of the inducible GAL1 promoter. As determined by indirect immunofluorescence, T7 RNA polymerase lacking the NLS remained mostly in the cytoplasm, whereas the protein containing the NLS localized to the nucleus. T7 RNA polymerase containing a mutated NLS remained mostly cytoplasmic. Hybrid proteins containing the NLS near the amino terminus were enzymatically active in the yeast cell, initiating transcription selectively at a T7 promoter placed in yeast chromosomal or plasmid DNA and stopping at a specific T7 terminator. At limiting enzyme concentrations, 5 to 10 times as much target RNA was produced when the polymerase contained the NLS, presumably because more enzyme reached the nucleus. Although substantial amounts of intact mRNA accumulated, no translation of target mRNAs in yeast cells was detected.

Microwave dielectric heating is finding greater acceptance in industrial processing. In particular, the parallel plate waveguide applicator is useful in the heating of thin films or webs. However, for materials which have a very small dielectric loss factor and thickness product, the parallel plate applicator does not provide sufficiently efficient coupling of microwave energy to the web. The present invention provides an applicator of improved efficiency and allows flexibility of choice of coupling along the length of the applicator. This is accomplished by inserting inductive elements of predetermined dimensions such as metallic rods or plates, at predetermined positions within the waveguide, providing for multiple electric reflections of the excitation field between the elements. Also by varying the susceptance of these elements, which includes varying the size and/or locations and the spacing of the elements or by inserting dielectric material into the guide, the coupling of microwave energy to the web may be varied and thus controlled over the length of the applicator.

Two studies are presented which deal with the reliability and validity of self-reports of aerobic activity. The first study compared two forms of self-report data obtained as part of a study of intervention strategy. The two forms were daily self-report and weekly retrospective report. Analyses covering the overlapping time period revealed differences in mean minutes engaged in activity, but modest and statistically significant correlations between the two forms among adults participating in the intervention group. No meaningful results were obtained among adults in the control group, nor among children in either group. The need for the development and testing of self-report forms among children was noted, and was the subject of the second study. In Study II, six different forms on which third to sixth grade children recorded their aerobic activity were compared against two days of continuous observations of their behavior. The six forms varied along two dimensions. The first dimension varied the...

The relationship between the research into creativity and the changes in school mathematics is investigated. Problems arising from this relationship and the research which attempts to solve them are considered. These include teaching styles such as the discovery methods, the measurement of creativity and the definition and measurement of mathematics creativity. Finally there is an attempt to look at tests which purport to measure creativity.

Gnanadesikan 1977 illustrates the utility of the power transformations considered by Moore and Tukey (1954) Box and Cox (1964), and Andrews, Gnanadesikan, and Warner (1971). These transformations have been used to obtain and assess both the marginal and joint normality of the underlying distributions. This paper investigates the utility of this procedure in defining homoscedastic transformations in multivariate populations.

We compared the sequence and properties of the chicken mos homolog with the previously characterized mouse and human c-mos genes. Sequence analysis revealed one major open reading frame of 1,047 base pairs encoding a protein of 349 amino acids. Both the nucleotide sequence and the deduced amino acid sequence showed 62% overall homology to mouse and human c-mos, but regions of higher conservation (approximately 70%) occurred in the putative ATP-binding and kinase domains. We detected mos transcripts by Northern (RNA) analyses in RNA prepared from chicken and quail ovaries and testes. Evidence for low levels of mos RNA expression in adult chicken heart, kidney, and spleen and in the entire embryo was obtained by S1 nuclease protection experiments. In contrast to the low transforming efficiency of human c-mos when linked to a mouse retroviral long terminal repeat element, chicken c-mos transformed NIH 3T3 cells as efficiently as mouse c-mos did. We also show that chicken primary embryo fibroblasts were morphologically altered when infected with an avian retroviral vector containing the chicken c-mos coding region.

We compared the sequence and properties of the chicken mos homolog with the previously characterized mouse and human c-mos genes. Sequence analysis revealed one major open reading frame of 1,047 base pairs encoding a protein of 349 amino acids. Both the nucleotide sequence and the deduced amino acid sequence showed 62% overall homology to mouse and human c-mos, but regions of higher conservation (approximately 70%) occurred in the putative ATP-binding and kinase domains. We detected mos transcripts by Northern (RNA) analyses in RNA prepared from chicken and quail ovaries and testes. Evidence for low levels of mos RNA expression in adult chicken heart, kidney, and spleen and in the entire embryo was obtained by S1 nuclease protection experiments. In contrast to the low transforming efficiency of human c-mos when linked to a mouse retroviral long terminal repeat element, chicken c-mos transformed NIH 3T3 cells as efficiently as mouse c-mos did. We also show that chicken primary embryo fibroblasts were morphologically altered when infected with an avian retroviral vector containing the chicken c-mos coding region.

Two separation indices are considered for partitions P = {X1, …, Xk} of a finite data set X in a general inner product space. Both indices increase as the pairwise distances between the subsets Xi become large compared to the diameters of Xi Maximally separated partitions p' are defined and it is shown that as the indices of p' increase without bound, the characteristic functions of Xi' in P' are approximated more and more closely by the membership functions in fuzzy partitions which minimize certain fuzzy extensions of the k-means squared error criterion function.

The applied electric field at the onset of polarization reversal during switching of a triglycine sulphate single crystal with a sinusoidal applied field has been measured as a function of crystal thickness. In contrast to the sinusoidal coercive field measurements of Pulvari and Kuebler (1958), this field is frequency independent and thickness dependent according to the relation En α (thickness)−2/3. The results are discussed as a nucleation phenomenon on the basis of a simple model and lead to an estimate of the domain wall surface energy of triglycine sulphate as being of the order of 1 erg/cm2. Finally a criticism of the theory is discussed.

A new radiotracer technique for determining wear rates of selected automotive engine parts is described and demonstrated for piston rings. The technique uses Fe55 instead of Fe59 as the radiotracer...

The use of doubly corrugated reactive chokes to reduce leakage from micro-wave systems for heating continuous webs is examined. It is demonstrated that such chokes provide substantial leakage reduction in a compact geometry, which allows ready access to the web.

(1974). Review of :“ Simulators for Skill. ” By ERIC O. WHEATCROFT. (London: McGraw-Hill, 1973.) [Pp. xi + 216.] £4 75. Ergonomics: Vol. 17, No. 4, pp. 549-551.