673 resultados para Pythagoras cup
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We examined the relations between selection for perception and selection for action in a patient FK, with bilateral damage to his temporal and medial frontal cortices. The task required a simple grasp response to a common object (a cup) in the presence of a distractor (another cup). The target was cued by colour or location, and FK made manual responses. We examined the effects on performance of cued and uncued dimensions of both the target and the distractor. FK was impaired at perceptually selecting the target when cued by colour, when the target colour but not its location changed on successive trials. The effect was sensitive to the relative orientations of targets and distractors, indicating an effect of action selection on perceptual selection, when perceptual selection was weakly instantiated. The dimension-specific carry-over effect on reaching was enhanced when there was a temporal delay between a cue and the response, and it disappeared when there was a between-trial delay. The results indicate that perceptual and action selection systems interact to determine the efficiency with which actions are selected to particular objects.
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An intelligent agent, operating in an external world which cannot be fully described in its internal world model, must be able to monitor the success of a previously generated plan and to respond to any errors which may have occurred. The process of error analysis requires the ability to reason in an expert fashion about time and about processes occurring in the world. Reasoning about time is needed to deal with causality. Reasoning about processes is needed since the direct effects of a plan action can be completely specified when the plan is generated, but the indirect effects cannot. For example, the action `open tap' leads with certainty to `tap open', whereas whether there will be a fluid flow and how long it might last is more difficult to predict. The majority of existing planning systems cannot handle these kinds of reasoning, thus limiting their usefulness. This thesis argues that both kinds of reasoning require a complex internal representation of the world. The use of Qualitative Process Theory and an interval-based representation of time are proposed as a representation scheme for such a world model. The planning system which was constructed has been tested on a set of realistic planning scenarios. It is shown that even simple planning problems, such as making a cup of coffee, require extensive reasoning if they are to be carried out successfully. The final Chapter concludes that the planning system described does allow the correct solution of planning problems involving complex side effects, which planners up to now have been unable to solve.
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Loss of optic nerve head (ONH) axons in primary open angle glaucoma (POAG) has been attributed to both mechanical and vascular factors. Confocal scanning laser ophthalmoscopy (cSLO) provides a promising tool for the topographic follow-up of the ONH in glaucoma, while scanning laser Doppler flowmetry (SLDF) facilitates the rapid non-invasive assessment of retinal capillary blood flow. The purposes of these investigations were to optimise the techniques and explore their potential to classify and monitor disease. Preliminary investigations explored the reproducibility and validity of cSLO and SLDF and showed that: For cSLO: In a model eye, measurements are accurate over a range of axial lengths. For best reproducibility, seven images per visit are required, with a contour line located on Elschnig's scleral ring and transferred automatically between images. For SLDF: Three perfusion images are required for optimum reproducibility. Physiological changes induced by gas perturbation can be measured. Cross-sectional comparison of groups of normal subjects and early POAG patients showed that: cSLO parameters differentiate the early POAG group. Blood volume measured by SLDF showed group differences in superior nasal retina only. Longitudinal investigation of ONH topography, haemodynamic and visual field indices in normal subjects and POAG patients showed that: cSLO detects topographical change over time more frequently in the POAG group. Important parameters include: C:D area ratio, cup and rim area, mean depth in contour, volumes above and below reference and surface. Factor analysis identified "cup" and "rim" factors that can be used to detect change over time in individual patients. Blood flow changes were most apparent in the inferior nasal peripapillary retina of the POAG group. Perimetry is of clinical value for the identification of glaucoma but is less sensitive than cSLO for monitoring glaucomatous change.
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Poster section INTRODUCTION. Retrospective Analysis PURPOSE. To evaluate the morphology and location of optic disc haemorrhages (ODH) identified at diabetic retinopathy (DR) screening to establish whether particular ODH are predictive of ocular disease (e.g. glaucoma). METHODS. Retrospective analysis of 77 patients who presented with ODH at DR screening in the Birmingham and Black Country screening programme between June 2009-March 2010. Mean age was 71 years (range 39-89). Cup/disc ratio (CDR), location and morphology of the haemorrhage were recorded. The outcome of the referral and the status of the ODH were followed up a year later. RESULTS. Of the 77 referred, 34 patients were unassessed for possible glaucoma. Of the 43 patients that were assessed in the hospital eye service for glaucoma, 11 (26%) were diagnosed with glaucoma. These glaucoma patients mostly presented with flame haemorrhages (64%) and blot haemorrhages (36%). Haemorrhages tended to adjoin the margin of the OD (64%), and were more commonly flame shaped (64%). They less commonly occurred in the optic disc itself (36%), and were all blot shaped. The OD Cup/disc ratio (CDR) of the patients with glaucoma (n=11) ranged from 0.33-0.57. It is interesting to note the highest CDR was 0.68 in the 77 patients referred. 32 patients were confirmed as not having glaucoma. 24 (75%) of these patients presented with an ODH adjoining the margin, of which 20 (83%) were flame, and 4 blot (17%) shaped. Only 8 (25%) presented with an ODH in the OD, of which 6 (75%) were blot shaped. One year follow up of the 77 referred cases revealed that the ODH resolved in 45 (57%) patients while 10 (13%) still had an ODH present. 15 (21%) were still under ophthalmology hence digital retinal photos were not available for assessment. Six patients (8%) (age range 71-91 years) died within the year, and one lost to follow up. CONCLUSIONS. The results suggest that a significant number of patients with ODH have glaucoma and that the differing morphology of the haemorrhage is not a major predictor i.e. blot versus flame shaped, adjoining or in the optic disc. The cup/disc ratio did not predict glaucoma either.
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Purpose: To determine whether curve-fitting analysis of the ranked segment distributions of topographic optic nerve head (ONH) parameters, derived using the Heidelberg Retina Tomograph (HRT), provide a more effective statistical descriptor to differentiate the normal from the glaucomatous ONH. Methods: The sample comprised of 22 normal control subjects (mean age 66.9 years; S.D. 7.8) and 22 glaucoma patients (mean age 72.1 years; S.D. 6.9) confirmed by reproducible visual field defects on the Humphrey Field Analyser. Three 10°-images of the ONH were obtained using the HRT. The mean topography image was determined and the HRT software was used to calculate the rim volume, rim area to disc area ratio, normalised rim area to disc area ratio and retinal nerve fibre cross-sectional area for each patient at 10°-sectoral intervals. The values were ranked in descending order, and each ranked-segment curve of ordered values was fitted using the least squares method. Results: There was no difference in disc area between the groups. The group mean cup-disc area ratio was significantly lower in the normal group (0.204 ± 0.16) compared with the glaucoma group (0.533 ± 0.083) (p < 0.001). The visual field indices, mean deviation and corrected pattern S.D., were significantly greater (p < 0.001) in the glaucoma group (-9.09 dB ± 3.3 and 7.91 ± 3.4, respectively) compared with the normal group (-0.15 dB ± 0.9 and 0.95 dB ± 0.8, respectively). Univariate linear regression provided the best overall fit to the ranked segment data. The equation parameters of the regression line manually applied to the normalised rim area-disc area and the rim area-disc area ratio data, correctly classified 100% of normal subjects and glaucoma patients. In this study sample, the regression analysis of ranked segment parameters method was more effective than conventional ranked segment analysis, in which glaucoma patients were misclassified in approximately 50% of cases. Further investigation in larger samples will enable the calculation of confidence intervals for normality. These reference standards will then need to be investigated for an independent sample to fully validate the technique. Conclusions: Using a curve-fitting approach to fit ranked segment curves retains information relating to the topographic nature of neural loss. Such methodology appears to overcome some of the deficiencies of conventional ranked segment analysis, and subject to validation in larger scale studies, may potentially be of clinical utility for detecting and monitoring glaucomatous damage. © 2007 The College of Optometrists.
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Early detection of glaucoma relies on a detailed knowledge of how the normal optic nerve (ONH) varies within the population. The purpose of this study focused on two main areas; 1. To explore the optic nerve head appearance in the normal optometric population and compare the south Asian (principally Pakistani) with the European white population, correcting for possible ocular and non-ocular influences in a multiple regression model. The main findings were: • The optic discs of the South Asian (SA) and White European (WE) populations were not statistically different in size. The SA group possessed discs with increased cupping and thinner neuro-retinal rims (NRR) compared with the WE group. The SA group also demonstrated a more vertically oval shape than the WE population. These differences were significant at the p<0.01 level. • The upper limits of inter-eye asymmetry were: ≤0.2 for cup to disc area ratio, and 3mmHg for intra-ocular pressure (IOP) for both ethnic groups and this did not increase with age. IOP asymmetry did not vary with gender, ethnicity or a family history of glaucoma and was independent of ONH asymmetry. ONH and IOP asymmetry are therefore independent risk factors when screening for glaucoma for both ethnic groups. 2. To investigate the validity of the ISNT rule: inferior> superior> nasal> temporal NRR thickness in the optometric population. The main findings were: • As disc size increased the disc become rounder and less vertically oval in shape. Vertically oval discs had thicker superior and inferior NRRs and thinner nasal and temporal NRRs compared with rounder disc shapes due to cup shape being independent of disc shape. Vertically oval discs were therefore more likely to obey the ISNT rule than larger rounder discs. • The ISNT rule has a low adherence in our sample of normal eyes (5.7%). However, by removing the nasal sector to become the IST rule, 74.5% of normal eyes obeyed. SA eyes and female gender were more likely to obey the ISNT rule due to increased disc ovality. The IST rule is independent of disc shape and therefore more suitable for assessing discs from both ethnic backgrounds. Obeying the ISNT rule or IST rule was not related to disc or cup size.
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Oral liquid formulations are ideal dosage forms for paediatric, geriatric and patient with dysphagia. Dysphagia is prominent among patients suffering from stroke, motor neurone disease, advanced Alzheimer’s and Parkinson’s disease. However oral liquid preparations are particularly difficult to formulate for hydrophobic and unstable drugs. Therefore current methods employed in solving this issue include the use of ‘specials’ or extemporaneous preparations. In order to challenge this, the government has encouraged research into the field of oral liquid formulations, with the EMEA and MHRA publishing list of drugs of interest. The current work investigates strategic formulation development and characterisation of select API’s (captopril, gliclazide, melatonin, L-arginine and lansoprazole), each with unique obstacles to overcome during solubilisation, stabilisation and when developing a palatable dosage from. By preparing a validated calibration protocol for each of the drug candidates, the oral liquid formulations were assessed for stability, according to the ICH guidelines along with thorough physiochemical characterisation. The results showed that pH and polarity of the solvent had the greatest influence on the extent of drug solubilisation, with inclusion of antioxidants and molecular steric hindrance influencing the extent of drug stability. Captopril, a hydrophilic ACE inhibitor (160 mg.mL-1), undergoes dimerisation with another captopril molecule. It was found that with the addition of EDTA and HP-β-CD, the drug molecule was stabilised and prevented from initiating a thiol induced first order free radical oxidation. The cyclodextrin provided further steric hindrance (1:1 molar ratio) resulting in complete reduction of the intensity of sulphur like smell associated with captopril. Palatability is a crucial factor in patient compliance, particularly when developing a dosage form targeted towards paediatrics. L-arginine is extremely bitter in solution (148.7 g.L-1). The addition of tartaric acid into the 100 mg.mL-1 formulation was sufficient to mask the bitterness associated with its guanidium ions. The hydrophobicity of gliclazide (55 mg.L-1) was strategically challenged using a binary system of a co-solvent and surfactant to reduce the polarity of the medium and ultimately increase the solubility of the drug. A second simpler method was developed using pH modification with L-arginine. Melatonin has two major obstacles in formulation: solubility (100 μg.mL-1) and photosensitivity, which were both overcome by lowering the dielectric constant of the medium and by reversibly binding the drug within the cyclodextrin cup (1:1 ratio). The cyclodextrin acts by preventing UV rays from reaching the drug molecule and initiated the degradation pathway. Lansoprazole is an acid labile drug that could only be delivered orally via a delivery vehicle. In oral liquid preparations this involved nanoparticulate vesicles. The extent of drug loading was found to be influenced by the type of polymer, concentration of polymer, and the molecular weight. All of the formulations achieved relatively long shelf-lives with good preservative efficacy.
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Full text: It seems a long time ago now since we were at the BCLA conference. The excellent FIFA World Cup in Brazil kept us occupied over the summer as well as Formula 1, Wimbledon, Tour de France, Commonwealth Games and of course exam paper marking! The BCLA conference this year was held in Birmingham at the International Convention Centre which again proved to be a great venue. The number of attendees overall was up on previous years, and at a record high of 1500 people. Amongst the highlights at this year's annual conference was the live surgery link where Professor Sunil Shah demonstrated the differences in technique between traditional phacoemulsification cataract surgery and femtosecond assisted phacoemulsification cataract surgery. Dr. Raquel Gil Cazorla, a research optometrist at Aston University, assisted in the procedure including calibrating the femtosecond laser. Another highlight for me was the session that I chaired, which was the international session organised by IACLE (International Association of CL Educators). There was a talk by Mirjam van Tilborg about dry eye prevalence in the Netherlands and how it was managed by medical general practitioners (GPs) or optometrists. It was interesting to know that there are only 2 schools of optometry there and currently under 1000 registered optometrists there. It also seems that GPs were more likely to blame CL as the cause for dry eye whereas optometrists who had a fuller range of tests were better at solving the issue. The next part of the session included the presentation of 5 selected posters from around the world. The posters were also displayed in the main poster area but were selected to be presented here as they had international relevance. The posters were: 1. Motivators and Barriers for Contact Lens Recommendation and Wear by Nilesh Thite (India) 2. Contact lens hygiene among Saudi wearers by Dr. Ali Masmaly (Saudi) 3. Trends of contact lens prescribing and patterns of contact lens practice in Jordan by Dr. Mera Haddad (Jordan) 4. Contact Lens Behaviour in Greece by Dr. Dimitra Makrynioti (Greece) 5. How practitioners inform ametropes about the benefits of contact lenses and overcome the potential barriers: an Italian survey, by Dr. Fabrizio Zeri (Italy) It was interesting to learn about CL practice in different parts, for example the CL wearing population ration in Saudi Arabia is around 1:2 Male:Female (similar to other parts of the world) and although the sale of CL is restricted to registered practitioners there are many unregistered outlets, like clothing stores, that flout the rules. In Jordan some older practitioners will still advise patients to use tap water or even saliva! But thankfully the newer generation of practitioners have been educated not to advise this. In Greece one of the concerns was that some practitioners may advise patients to use disposable lenses for longer than they should and again it seems to be the practitioners with inadequate education that would do this. In India it was found that cost was one barrier to using contact lenses but also some practitioners felt that they shouldn’t offer CLs due to cost too. In Italy sensitive eyes and CL care and maintenance were the barriers to CL wear but the motivators were vision and comfort and aesthetics. Finally the international session ended with the IACLE travel award and educator awards presented by IACLE president Shehzad Naroo and BCLA President Andrew Yorke. The travel award went to Wang Ling, Jinling Institute of Technology, Nanjing, China. There were 3 regional Contact Lens Educator of the Year Awards sponsored by Coopervision and presented by Dr. J.C. Aragorn of Coopervision. 1. Asia Pacific Region – Dr. Rajeswari Mahadevan of Sankara Nethralaya Medical Research Foundation, Chennai, India 2. Americas Region – Dr. Sergio Garcia of University of La Salle, Bogotá and the University Santo Tomás, Bucaramanga, Colombia 3. Europe/Africa – Middle East Region: Dr. Eef van der Worp, affiliated with the University of Maastricht, the Netherlands The posters above were just a small selection of those displayed at this year's BCLA conference. If you missed the BCLA conference then you can see the abstracts for all posters and talks in a virtual issue of CLAE very soon. The poster competition was kindly sponsored by Elsevier. The poster winner this year was: Joan Gispets – Corneal and Anterior Chamber Parameters in Keratoconus The 3 runners up were: Debby Yeung – Scleral Lens Central Corneal Clearance Assessment with Biomicroscopy Sarah L. Smith – Subjective Grading of Lid Margin Staining Heiko Pult – Impact of Soft Contact Lenses on Lid Parallel Conjunctival Folds My final two highlights are a little more personal. Firstly, I was awarded Honorary Life Fellowship of the BCLA for my work with the Journal, and I would like to thank the BCLA, Elsevier, the editorial board of CLAE, the reviewers and the authors for their support of my role. My final highlight from the BCLA conference this year was the final presentation of the conference – the BCLA Gold Medal award. The recipient this year was Professor Philip Morgan with his talk ‘Changing the world with contact lenses’. Phil was the person who advised me to go to my first BCLA conference in 1994 (funnily he didn’t attend himself as he was busy getting married!) and now 20 years later he was being honoured with the accolade of being the BCLA Gold Medallist. The date of his BCLA medal addressed was shared with his father's birthday so a double celebration for Phil. Well done to outgoing BCLA President Andy Yorke and his team at the BCLA (including Nick Rumney, Cheryl Donnelly, Sarah Greenwood and Amir Khan) on an excellent conference. And finally welcome to new President Susan Bowers. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
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2000 Mathematics Subject Classification: Primary 46E15, 54C55; Secondary 28B20.
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Neste ensaio pretendemos problematizar algumas lógicas sociais não explícitas que se articulam ao domínio de realização da Copa do Mundo FIFA. Para tanto, privilegiamos como recorte analítico a edição de 2010 deste evento, de modo a desvelarmos algumas das retóricas e ações estratégicas que permearam o contexto de sua realização na África do Sul. Com base em dados obtidos na literatura acadêmica e mídia, buscamos apresentar que as motivações para o evento se baseavam em discursos desenvolvimentistas por parte tanto da FIFA quanto das elites locais sul-africanas visando o convencimento e apoio por parte de diferentes grupos sociais. Entretanto, as consequências não foram necessariamente aquelas prometidas, sendo essas instituições as reais beneficiadas em seus interesses econômicos e políticos. Nesse ponto, argumentamos que a sociedade brasileira pode e deve aprender com essa experiência para avaliar de forma crítica os motivos menos aparentes de sediar eventos desse porte. In this essay, we intend to discuss some social logics not explicit that articulate the domain of the FIFA World Cup. Therefore, the 2010 edition of this event is used as analytical approach to reveal some of the rhetoric and strategic actions that permeated the context of its realization. Based on data obtained in the academic literature and media, we present that the motivations for the event were based on developmental discourses by both FIFA as well as local elites South African aiming to convince different social groups and conquer their support. However, the consequences are not necessarily those promised, and these institutions were the real beneficiaries in their economic and political mutual interests. At this point, we argue that Brazilian society can and should learn from the experience of South Africa to assess critically the motives less apparent to host such events.
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Georgi Dimkov - Looking at the performance of a violonist we perceive that the four strings of the instrument produces tones different pitches. It is clear that the artist presses the strings on special places and that changes the pitch. These places are determined practically by the musicians. Is it possible to determine these places theoretically, from some abstract point of view? After the legend the first successive investigations in this field were done by Pythagoras. The development of the ideas for improvement and enlargement of the results of Pythagoras is the mane topic of the present paper.
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The penalty kick in football is a seemingly simplistic play; however, it has increased in complexity since 1997 when the rules changed allowing goalkeepers to move laterally along their goal line before the ball was kicked. Prior to 1997 goalkeepers were required to remain still until the ball was struck. The objective of this study was to determine the importance of the penalty kick in the modern game of football. A retrospective study of the 2002, 2006 and 2010 World Cup and the 2000, 2004 and 2008 European Championship tournaments was carried out, assessing the importance of the penalty kick in match play and shootouts and the effect of the time of the game on the shooter's success rate. This study demonstrated the conversion rate of penalties was 73% in shootouts and 68% in match play. Significantly more penalties were awarded late in the game: twice as many penalties in the second half than the first and close to four times as many in the fourth quarter vs. the first. Teams awarded penalty kicks during match play won 52%, drew 30% and lost 18% of the time; chances of winning increased to 61% if the penalty was scored, but decreased to 29% if missed. Teams participating in either the World Cup or European Championship final match had roughly a 50% chance of being involved in a penalty shootout during the tournament. Penalty shots and their outcome significantly impact match results in post 1997 football.
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Brazilians greeted the long-awaited decision of making Rio de Janeiro the host of the 2016 Olympic Games with tremendous exhilaration. Although Rio’s fantastic natural beauty certainly added to its attraction in hosting the games, its alarming rates of urban crime and violence largely associated with drug trafficking immediately triggered worldwide criticism, and put at issue its ability to guarantee the security for the games. Brazilians have been vying for a position as an emerging global economy and understand the importance of the Games for international prestige. This makes the stakes very high when hosting the Olympic Games in the wake of the 2014 Soccer World Cup, which will also be held in Brazil. This paper explores these criticisms and assesses Rio’s ability to prepare for this important event. The paper further explores the consensus that Brazilians will be more equipped to address actions taken by organized crime capable of affecting the Olympic Games than to face a terrorist attack. Brazil – and Rio – does not figure in the “terrorism map” as a region particularly linked to terrorism. Aside from uncorroborated suspicions of activities by terrorist organizations on the Tri-Border region (Argentina, Brazil, and Paraguay), Brazil does not elicit many concerns regarding terrorism.1 Yet, there is no way to guarantee that terrorist organizations will not try to make use of the 2016 Rio Olympic Games to advance their agenda. This being in mind, Rio and Brazil in general face a long road ahead to prepare, prevent, protect and respond to a possible terrorist attack during the 2016 Olympics. It is clear that prevention and preparation towards potential threats to the Games must necessarily include cooperation and exchange of best practices with other countries. 1 U.S. Department of State has confirmed that this area may have been used to transport weapons and conduct financial affairs in the past. This type of activity has been made more difficult with the fortification of border controls in more recent times.
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Small states that lack capacity and act on their own may fall victim to international and domestic terrorism, transnational organized crime or criminal gangs. The critical issue is not whether small Caribbean states should cooperate in meeting security challenges, but it is rather in what manner, and by which mechanisms can they overcome obstacles in the way of cooperation. The remit of the Regional Security System (RSS) has expanded dramatically, but its capabilities have improved very slowly. The member governments of the RSS are reluctant to develop military capacity beyond current levels since they see economic and social development and disaster relief as priorities, requiring little investment in military hardware. The RSS depends on international donors such as the USA, Canada, Great Britain, and increasingly China to fund training programs, maintain equipment and acquire material. In the view of most analysts, an expanded regional arrangement based on an RSS nucleus is not likely in the foreseeable future. Regional political consensus remains elusive and the predominance of national interests over regional considerations continues to serve as an obstacle to any CARICOM wide regional defense mechanism. Countries in the Caribbean, including the members of the RSS, have to become more responsible for their own security from their own resources. While larger CARICOM economies can do this, it would be difficult for most OECS members of the RSS to do the same. The CARICOM region including the RSS member countries, have undertaken direct regional initiatives in security collaboration. Implementation of the recommendations of the Regional Task Force on Crime and Security (RTFCS) and the structure and mechanisms created for the staging of the Cricket World Cup (CWC 2007) resulted in unprecedented levels of cooperation and permanent legacy institutions for the regional security toolbox. The most important tier of security relationships for the region is the United States and particularly USSOUTHCOM. The Caribbean Basin Security Initiative [CBSI] in which the countries of the RSS participate is a useful U.S. sponsored tool to strengthen the capabilities of the Caribbean countries and promote regional ownership of security initiatives. Future developments under discussion by policy makers in the Caribbean security environment include the granting of law enforcement authority to the military, the formation of a single OECS Police Force, and the creation of a single judicial and law enforcement space. The RSS must continue to work with its CARICOM partners, as well as with the traditional “Atlantic Powers” particularly Canada, the United States and the United Kingdom to implement a general framework for regional security collaboration. Regional security cooperation should embrace wider traditional and non-traditional elements of security appropriate to the 21st century. Security cooperation must utilize to the maximum the best available institutions, mechanisms, techniques and procedures already available in the region. The objective should not be the creation of new agencies but rather the generation of new resources to take effective operations to higher cumulative levels. Security and non-security tools should be combined for both strategic and operational purposes. Regional, hemispheric, and global implications of tactical and operational actions must be understood and appreciated by the forces of the RSS member states. The structure and mechanisms, created for the staging of Cricket World Cup 2007 should remain as legacy institutions and a toolbox for improving regional security cooperation in the Caribbean. RSS collaboration should build on the process of operational level synergies with traditional military partners. In this context, the United States must be a true partner with shared interests, and with the ability to work unobtrusively in a nationalistic environment. Withdrawal of U.S. support for the RSS is not an option.