1,914 research outputs found
KINEMATIC AND KINETIC STUDIES ON MEASUREMENT OF ROWING TECHNIQUE
China's rowing performance is good when compared with other
Asian countries in Asia (e.g. Chinese athletes took away 7 of the 8 gold medals in the Xth Asian Games in 1986), but compared with world-class teams, there is still a long way to go. In the 1987 World Championships China won only bronze in the women's coxless four, and was only fourth of women's sculling in the World Youth Championships.
In order to solve the problems in rowing technique, training and
athletes-selection, a research group was set up and a series of studies were conducted on the rowing technique of elite Chinese rowers from national and some provincial teams. As a consequence, technical data, pictures and suggestions were provided, which have made contributions to the improvement of China's rowing performance
The phase-dependent Infrared brightness of the extrasolar planet upsilon Andromedae b
The star upsilon Andromeda is orbited by three known planets, the innermost
of which has an orbital period of 4.617 days and a mass at least 0.69 that of
Jupiter. This planet is close enough to its host star that the radiation it
absorbs overwhelms its internal heat losses. Here we present the 24 micron
light curve of this system, obtained with the Spitzer Space Telescope. It shows
a clear variation in phase with the orbital motion of the innermost planet.
This is the first demonstration that such planets possess distinct hot
substellar (day) and cold antistellar (night) faces.Comment: "Director's cut" of paper to appear in Science, 27 October, 200
Application of firefly luciferase assay for adenosine triphosphate (ATP) to antimicrobial drug sensitivity testing
The development of a rapid method for determining microbial susceptibilities to antibiotics using the firefly luciferase assay for adenosine triphosphate (ATP) is documented. The reduction of bacterial ATP by an antimicrobial agent was determined to be a valid measure of drug effect in most cases. The effect of 12 antibiotics on 8 different bacterial species gave a 94 percent correlation with the standard Kirby-Buer-Agar disc diffusion method. A 93 percent correlation was obtained when the ATP assay method was applied directly to 50 urine specimens from patients with urinary tract infections. Urine samples were centrifuged first to that bacterial pellets could be suspended in broth. No primary isolation or subculturing was required. Mixed cultures in which one species was predominant gave accurate results for the most abundant organism. Since the method is based on an increase in bacterial ATP with time, the presence of leukocytes did not interfere with the interpretation of results. Both the incubation procedure and the ATP assays are compatible with automation
Infrared Observations During the Secondary Eclipse of HD 209458b: I. 3.6-Micron Occultation Spectroscopy Using the VLT
We search for an infrared signature of the transiting extrasolar planet HD
209458b during secondary eclipse. Our method, which we call `occultation
spectroscopy,' searches for the disappearance and reappearance of weak spectral
features due to the exoplanet as it passes behind the star and later reappears.
We argue that at the longest infrared wavelengths, this technique becomes
preferable to conventional `transit spectroscopy'. We observed the system in
the wing of the strong nu-3 band of methane near 3.6 microns during two
secondary eclipses, using the VLT/ISAAC spectrometer at a spectral resolution
of 3300. Our analysis, which utilizes a model template spectrum, achieves
sufficient precision to expect detection of the spectral structure predicted by
an irradiated, low-opacity (cloudless), low-albedo, thermochemical equilibrium
model for the exoplanet atmosphere. However, our observations show no evidence
for the presence of this spectrum from the exoplanet, with the statistical
significance of the non-detection depending on the timing of the secondary
eclipse, which depends on the assumed value for the orbital eccentricity. Our
results reject certain specific models of the atmosphere of HD 209458b as
inconsistent with our observations at the 3-sigma level, given assumptions
about the stellar and planetary parameters.Comment: 26 pages, 8 figures Accepted to Astrophysical Journa
Loudness perceptions influence feelings of interpersonal closeness and protect against detrimental psychological effects of social exclusion
We propose that perceptions of auditory loudness and interpersonal closeness are bidirectionally related. Across 12 experiments (total N = 2219; 10 preregistered; with Singaporean, British, U.S. American, Indian, and Australian participants), we demonstrated that louder audio made people feel physically (Study 1a) and socially (Study 1b) closer to others, presumably because of loudness activates interpersonal closeness-related concepts implicitly (Studies 1c, 1d). This loudness-interpersonal closeness effect was observed across diverse samples (Studies 2a, 3a, S1), for longer listening intervals (Study 2b), and in natural settings (Studies 3a, 3b). Conversely, individuals made to feel socially excluded rated their surroundings as quieter (Study 4). Furthermore, following social exclusion, individuals showed a preference for louder volume (Study 5). Finally, exposure to loud stimuli mitigated detrimental psychological effects of social exclusion (Study 6). Theoretical implications for the social cognition of loudness, social exclusion and compensatory strategies, and practical implications for ameliorating loneliness are discussed
C-myc amplification in breast cancer: a meta-analysis of its occurrence and prognostic relevance
Data from basic research suggests that amplification of the proto-oncogene c-myc is important in breast cancer pathogenesis, but its frequency of amplification and prognostic relevance in human studies have been inconsistent. In an effort to clarify the clinical significance of c-myc amplification in breast cancer, we conducted a comprehensive literature search and a meta-analysis in which 29 studies were evaluated. The weighted average frequency of c-myc amplification in breast tumours was 15.7% (95% CI = 12.5–18.8%), although estimates in individual studies exhibited significant heterogeneity, P< 0.0001. C-myc amplification exhibited significant but weak associations with tumour grade (RR = 1.61), lymph-node metastasis (RR = 1.24), negative progesterone receptor status (RR = 1.27), and postmenopausal status (RR = 0.82). Amplification was significantly associated with risk of relapse and death, with pooled estimates RR = 2.05 (95% CI = 1.51–2.78) and RR = 1.74 (95% CI = 1.27–2.39), respectively. This effect did not appear to be merely a surrogate for other prognostic factors. These results suggest that c-myc amplification is relatively common in breast cancer and may provide independent prognostic information. More rigorous studies with consistent methodology are required to validate this association, and to investigate its potential as a molecular predictor of specific therapy response. © 2000 Cancer Research Campaign http://www.bjcancer.co
Evaluation of a recombination-resistant coronavirus as a broadly applicable, rapidly implementable vaccine platform
Emerging and re-emerging zoonotic viral diseases are major threats to global health, economic stability, and national security. Vaccines are key for reducing coronaviral disease burden; however, the utility of live-attenuated vaccines is limited by risks of reversion or repair. Because of their history of emergence events due to their prevalence in zoonotic pools, designing live-attenuated coronavirus vaccines that can be rapidly and broadly implemented is essential for outbreak preparedness. Here, we show that coronaviruses with completely rewired transcription regulatory networks (TRNs) are effective vaccines against SARS-CoV. The TRN-rewired viruses are attenuated and protect against lethal SARS-CoV challenge. While a 3-nt rewired TRN reverts via second-site mutation upon serial passage, a 7-nt rewired TRN is more stable, suggesting that a more extensively rewired TRN might be essential for avoiding growth selection. In summary, rewiring the TRN is a feasible strategy for limiting reversion in an effective live-attenuated coronavirus vaccine candidate that is potentially portable across the Nidovirales order
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