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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
Vulnerability to natural disasters in a rapidly growing, affluent society, British Columbia, Canada
British Columbia is a province that experienced rapid demographic, urban and economic growth in the past few decades. It is a modern and technologically sophisticated society. Although the province possesses the knowledge and resources to combat most dangers that threaten its people and communities, these dangers continue to outstrip the precautions and safety measures in place. The reasons for this seem to lie less in the characteristics of dangers or hazards, but rather relate to socioeconomic processes and organisations that disadvantage particular people, groups and sectors of the population, or make them more vulnerable to dangers than others. This thesis is directed towards exploring this phenomenon. The main objectives of this thesis are to: (1) examine the vulnerability to natural disasters of British Columbia’s people and communities, and (2) demonstrate how socioeconomic order and processes can create or exacerbate different forms of vulnerability in some groups. These objectives are met mainly by applying existing vulnerability theories to British Columbia, including how we describe vulnerable individuals, groups and sectors, the forms of vulnerability that affect them, and the forces that contribute to them. British Columbia’s recent prosperity and growth marginalised some individuals, groups and communities, pushing them closer to the edge of the province’s social, economic and political systems. They widened social gaps and regional differentiation between Vancouver and the rest of the province, leaving some groups disadvantaged, powerless, unprotected, and/or exposed to dangers. Issues of vulnerability that pertain to peripheral resource communities include: (1) dependency on industries that are mobile, and controlled by unstable world market prices and availability of the remaining resources that they extract, (2) little to no influence on policies and organisations that affect their own interests and govern public resources, and (3) deterioration of physical landscape from resource extraction. In Vancouver, rising living costs sent people seeking accommodation elsewhere, resulting in some people living in more vulnerable locations or situations. These include: (1) homelessness and involvement in illegal activities such as prostitution and drug trafficking and use, (2) those who migrated further from work, placing them in vehicles for longer periods of time, and thus increasing exposure to road risks, (3) those who migrated to satellite and peripheral communities which in themselves are often more vulnerable, and (4) those who remained in Vancouver where higher living costs meant less resources available for other “non-essential” expenditures. Other issues contributing to vulnerability in some individuals, groups or sectors include: (1) dependencies, (2) tenancy, (3) poverty, and (4) tourists and other visitors
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 () 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
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