A global climatology of wind–wave interaction

Generally, ocean waves are thought to act as a drag on the surface wind so that momentum is transferred downwards, from the atmosphere into the waves. Recent observations have suggested that when long wavelength waves, characteristic of remotely generated swell, propagate faster than the surface wind momentum can also be transferred upwards. This upward momentum transfer acts to accelerate the near-surface wind, resulting in a low-level wave-driven wind jet. Previous studies have suggested that the sign reversal of the momentum flux is well predicted by the inverse wave age, the ratio of the surface wind speed to the speed of the waves at the peak of the spectrum. ECMWF ERA-40 data has been used here to calculate the global distribution of the inverse wave age to determine whether there are regions of the ocean that are usually in the wind-driven wave regime and others that are generally in the wave-driven wind regime. The wind-driven wave regime is found to occur most often in the mid-latitude storm tracks where wind speeds are generally high. The wave-driven wind regime is found to be prevalent in the tropics where wind speeds are generally light and swell can propagate from storms at higher latitudes. The inverse wave age is also a useful indicator of the degree of coupling between the local wind and wave fields. The climatologies presented emphasise the non-equilibrium that exists between the local wind and wave fields and highlight the importance of swell in the global oceans

An Examination of εαββατισμÓς and κατáπανσις in Hebrews 3:7-4:13 in Light of Their Old Testament Background

This paper will attempt to investigate and further define the two ideas of rest in Hebrews 3:7-4:13

The Use of the Blood Lactate Curve to Develop Training Intensity Guidelines for the Sports of Track and Field and Cross-Country

Int J Exerc Sci 5(2) : 148-159, 2012. The purpose of this study was to develop and field test a standardized system of training intensity guidelines for the sport of track and field/cross country, modeled after the standardized system of training intensity guidelines developed, adopted, and in use by U.S.A. Swimming. This study was quantitative and focused on the development and field-testing of standardized training intensity guidelines, based on the blood lactate curve and energy metabolism. The findings showed that as intensity increased so did participants’ blood lactate concentration, heart rate, and ratings of perceived exertion. A Pearson product-moment correlation analysis between the mean values of blood lactate concentration, heart rate, and ratings of perceived exertion, and the corresponding training intensity ranges revealed significant positive correlations between mean blood lactate values (r = 0.99, p \u3c 0.001), mean heart rate (r = 0.96, p \u3c 0.001); and ratings of perceived exertion (r = 0.99, p \u3c 0.005). Correlation analyses between heart rate and measures of blood lactate were positive (r = 0.70, p \u3e 0.05), as were heart rate and ratings of perceived exertion (r = 0.96, p \u3c 0.005). Measures of blood lactate were positively and significantly correlated to ratings of perceived exertion (r = 0.82, p \u3c 0.05). These findings validated the training intensity guidelines model

Laboratory observation of a nonlinear interaction between shear Alfv\'{e}n waves

An experimental investigation of nonlinear interactions between shear Alfv\'{e}n waves in a laboratory plasma is presented. Two Alfv\'{e}n waves, generated by a resonant cavity, are observed to beat together, driving a low frequency nonlinear psuedo-mode at the beat frequency. The psuedo-mode then scatters the Alfv\'{e}n waves, generating a series of sidebands. The observed interaction is very strong, with the normalized amplitude of the driven psuedo-mode comparable to the normalized magnetic field amplitude ($\delta B/B$) of the interacting Alfv\'{e}n waves.Comment: 10 pages, 4 figures, submitted to Phys. Rev. Let

Evaluation results of a 3D virtual environment for internet-accessible physics experiments

In the science of physics the interrelation of physical theory, model and experiement is hard to comprehend, therefore group learning becomes more important. This fact, combined with the opportunity to work on practical experiences over distance in a collaboratively way, has raised worldwide the interest of creating new learning environments based on 3D virtual worlds.This paper outlines an evaluation that was performed to determine whether the addition of collaborative virtual learning environment (CVLE) to an internet-accessible physics experiment (iLab) would improve learning experience. We wanted to assess if the developed CLVE helps participants to achieve a better understanding of physics phenomena. Within this CLVE avatars represent learners and they are able to communicate and collaborate in a way similar to real life in order to perform physics experiments using the TEAL simulation toolkit. One of the major findings of this evaluation indicates that the reconsideration of design and additional items at the 3D visualization could further improve the learning process in the CLVE in a more effective way

Illness perceptions of gout patients and the use of allopurinol in primary care: baseline findings from a prospective cohort study

Background Patients’ perceptions of their illness are dynamic and can directly influence aspects of management. Our aim was to examine the illness perceptions of gout patients in UK primary care and associations with allopurinol use. Methods A health questionnaire was sent to 1805 people with gout aged ≥18 years identified by a gout diagnosis or prescriptions for allopurinol or colchicine in their primary care medical records in the preceding 2 years. The questionnaire included selected items from the revised illness perception questionnaire (IPQ-R). Associations between illness perceptions and use of allopurinol were calculated using multinomial logistic regression adjusted for age, gender, deprivation status, body mass index, alcohol consumption, comorbidities and gout characteristics. Results One thousand one hundred eighty-four participants responded to the baseline questionnaire (65.6 %). Approximately half of responders perceived that they were able to control (51.2 %) or affect their gout through their own actions (44.8 %). Three quarters perceived treatments to be effective (76.4 %) and agreed that gout is a serious condition (76.4 %). Patients who agreed that they could control their gout (Relative Risk Ratio, 95 % confidence interval 1.66 (1.12 to 2.45)) and that treatments were effective (2.24 (1.32 to 3.81)) were more likely to currently be using allopurinol than not using allopurinol. However, this significance was attenuated after adjustment for self-reported gout characteristics (1.39 (0.89 to 2.17) & 1.78 (0.96 to 3.29) respectively). Conclusions Patients who perceive that they can control their gout and that treatments are effective are more likely to be using allopurinol, this suggests that better information is needed for the patient from GPs and rheumatologist to reassure and support their use of UL

Ambitious partnership needed for reliable climate prediction.

Current global climate models struggle to represent precipitation and related extreme events, with serious implications for the physical evidence base to support climate actions. A leap to kilometre-scale models could overcome this shortcoming but requires collaboration on an unprecedented scale

Carbohydrate reserves in grapevine (Vitis vinifera L. 'Chasselas'): the influence of the leaf to fruit ratio

Seasonal dynamics of total non-structural carbohydrates (TNC) in relation to the leaf-fruit ratio were measured over five years at different grapevine phenological stages in one- and two-year-old canes, trunks and roots of the cultivar 'Chasselas' (Vitis vinifera L.). Carbohydrates were mainly stored as starch in different parts of the grapevine during the growing season. Soluble carbohydrates represented only a small part (< 7 % of dry weight, DW) of the TNC. In the roots and trunks, the starch content fluctuated during the growing season, reaching the lowest values between budbreak and flowering depending on the year, and the highest values between harvest and leaf fall. The soluble sugar content increased in the trunks and the two-year-old canes during the winter period with the decrease in temperatures. A negative correlation was established between the average air temperature recorded during the seven days before sample collection for carbohydrate analysis, and soluble carbohydrate content in the trunks and two-year-old canes. The leaffruit ratio (source-sink), expressed by the “light-exposed leaf area∙kg-1 fruit”, not only substantially influenced the soluble sugar content in berries but also the starch and TNC concentrations in the trunks and roots at harvest. Higher leaf-fruit ratios resulted in increased starch and TNC concentrations in the trunks and roots, which attained the maximum values when the leaf-fruit ratio neared 2.0 m2 of light-exposed leaf area∙kg-1 fruit. Canopy height and leaf area had no predominant influence on the soluble sugars, starch contents, or TNC in the permanent vine parts. 

Mercury Orbiter: Report of the Science Working Team

The results are presented of the Mercury Orbiter Science Working Team which held three workshops in 1988 to 1989 under the auspices of the Space Physics and Planetary Exploration Divisions of NASA Headquarters. Spacecraft engineering and mission design studies at the Jet Propulsion Lab were conducted in parallel with this effort and are detailed elsewhere. The findings of the engineering study, summarized herein, indicate that spin stabilized spacecraft carrying comprehensive particles and fields experiments and key planetology instruments in high elliptical orbits can survive and function in Mercury orbit without costly sun shields and active cooling systems