Future wave climate over the west-European shelf seas

In this paper, we investigate changes in the wave climate of the west-European shelf seas under global warming scenarios. In particular, climate change wind fields corresponding to the present (control) time-slice 1961–2000 and the future (scenario) time-slice 2061–2100 are used to drive a wave generation model to produce equivalent control and scenario wave climate. Yearly and seasonal statistics of the scenario wave climates are compared individually to the corresponding control wave climate to identify relative changes of statistical significance between present and future extreme and prevailing wave heights. Using global, regional and linked global–regional wind forcing over a set of nested computational domains, this paper further demonstrates the sensitivity of the results to the resolution and coverage of the forcing. It suggests that the use of combined forcing from linked global and regional climate models of typical resolution and coverage is a good option for the investigation of relative wave changes in the region of interest of this study. Coarse resolution global forcing alone leads to very similar results over regions that are highly exposed to the Atlantic Ocean. In contrast, fine resolution regional forcing alone is shown to be insufficient for exploring wave climate changes over the western European waters because of its limited coverage. Results obtained with the combined global–regional wind forcing showed some consistency between scenarios. In general, it was shown that mean and extreme wave heights will increase in the future only in winter and only in the southwest of UK and west of France, north of about 44–45° N. Otherwise, wave heights are projected to decrease, especially in summer. Nevertheless, this decrease is dominated by local wind waves whilst swell is found to increase. Only in spring do both swell and local wind waves decrease in average height

Accounting for multivariate probabilities of failure in vertical seawall reliability assessments

The aim of this paper is to appraise the current knowledge on seawall performance and reliability, and to make the case for improved reliability assessments of vertical seawalls, which are used here as a representative for coastal flood defences. In order to achieve this aim, a brief introduction to flood risk management is first given. Then, vertical seawalls are introduced, and their most prominent failure modes are discussed. Reliability analysis is introduced within the context of flood risk management. More specifically, the fragility curve approach that is currently in use in industry is described, and its limitations are discussed. Finally, it is argued that recent advances in multivariate extreme value models would enable improvements to the approaches currently applied in practice. It is stressed that future risk assessment models of coastal flood defences ought to include multiple failure modes and their interactions, a thorough analysis of the model uncertainties, and potential computational costs, in view of providing practitioners with an improved and functional risk assessment tool. Carter, Magar, Simm, Gouldby & Walli

70 Years of Human Rights in Global Health: Drawing on a Contentious Past to Secure a Hopeful Future

The Universal Declaration of Human Rights, adopted on Dec 10, 1948, established a modern human rights foundation that has become a cornerstone of global health, central to public health policies, programmes, and practices. To commemorate the 70th anniversary of this seminal declaration, we trace the evolution of human rights in global health, linking the past, present, and future of health as a human right. This future remains uncertain. As contemporary challenges imperil continuing advancements, threatening both human rights protections and global health governance, the future will depend, as it has in the past, on sustained political engagement to realise human rights in global health

A study of comparing single dose granisetron with combination of granisetron with dexamethasone in preventing postoperative nausea vomiting in laparoscopic cholecystectomies

Background: Postoperative nausea and vomiting (PONV) remains a vexing problem despite of advances in anaesthesia care. PONV is distressing adverse effect after anaesthesia and surgery, resulting in significant morbidity due to acute discomfort associated with emetic symptoms and longer stays in the recovery room or unexpected hospital admission in ambulatory settings.Methods: A prospective, randomized, double blind comparative study was conducted to compare the efficacy and adverse effects of injection granisetron 40µg/kg as a single dose and injection granisetron in two different doses (20µg/kg and 40µg/kg) in combination with dexamethasone 160µg/kg for prevention of postoperative nausea and vomiting in patients undergoing general anaesthesia for elective laparoscopic cholecystectomy.Results: Nausea and vomiting were observed postoperatively at 0, 1, 2, 4, 8, and 24 consecutive hours after patient responded to verbal commands. Intensity of nausea graded verbally with an eleven point score (0-10) with those patients who scored their nausea as zero were termed nausea free, and 10 being most severe. Nausea scores when patient complains of nausea & if patient demand rescue antiemetic for nausea was noted down along with adverse effects if any. The data was analysed by ANOVA followed by unpaired‘t’ test, Chi-square/Fischer exact test or Kruskal Wallis Test.Conclusions: Granisetron as a single agent in dose 40µg/kg is effective as prophylactic antiemetic in preventing PONV in laparoscopic cholecystectomy whereas addition of dexamethasone 160µg/kg to granisetron significantly increases antiemetic efficacy of the granisetron in both the doses i.e. 20µg/kg and 40µg/kg without increasing any side effect. Granisetron 40µg//kg+injection dexamethasone 160µg/kg is best for antiemetic prophylaxis in highly emetogenic surgeries like laparoscopic cholecystectomy.  Granisetron 20µg/kg + injection dexamethasone can be cost effective alternative for routine antiemetic prophylaxis compared to granisetron 40µg//kg and granisetron 40µg//kg+ injection dexamethasone for all patients undergoing laparoscopic cholecystectomy.

Adaptive Disturbance Tracking Theory with State Estimation and State Feedback for Region II Control of Large Wind Turbines

A theory called Adaptive Disturbance Tracking Control (ADTC) is introduced and used to track the Tip Speed Ratio (TSR) of 5 MW Horizontal Axis Wind Turbine (HAWT). Since ADTC theory requires wind speed information, a wind disturbance generator model is combined with lower order plant model to estimate the wind speed as well as partial states of the wind turbine. In this paper, we present a proof of stability and convergence of ADTC theory with lower order estimator and show that the state feedback can be adaptive

Rogue Waves: From Nonlinear Schrödinger Breather Solutions to Sea-Keeping Test

Under suitable assumptions, the nonlinear dynamics of surface gravity waves can be modeled by the one-dimensional nonlinear Schrödinger equation. Besides traveling wave solutions like solitons, this model admits also breather solutions that are now considered as prototypes of rogue waves in ocean. We propose a novel technique to study the interaction between waves and ships/structures during extreme ocean conditions using such breather solutions. In particular, we discuss a state of the art sea-keeping test in a 90-meter long wave tank by creating a Peregrine breather solution hitting a scaled chemical tanker and we discuss its potential devastating effects on the ship

Experimental and numerical investigation of the effect of different shapes of collars on the reduction of scour around a single bridge pier

The scour phenomenon around bridge piers causes great quantities of damages annually all over the world. Collars are considered as one of the substantial methods for reducing the depth and volume of scour around bridge piers. In this study, the experimental and numerical methods are used to investigate two different shapes of collars, i.e, rectangular and circular, in terms of reducing scour around a single bridge pier. The experiments were conducted in hydraulic laboratory at university of Malaya. The scour around the bridge pier and collars was simulated numerically using a three-dimensional, CFD model namely SSIIM 2.0, to verify the application of the model. The results indicated that although, both types of collars provides a considerable decrease in the depth of the scour, the rectangular collar, decreases scour depth around the pier by 79 percent, and has better performance compared to the circular collar. Furthermore, it was observed that using collars under the stream's bed, resulted in the most reduction in the scour depth around the pier. The results also show the SSIIM 2.0 model could simulate the scour phenomenon around a single bridge pier and collars with sufficient accuracy. Using the experimental and numerical results, two new equations were developed to predict the scour depth around a bridge pier exposed to circular and rectangular collars