An integrated approach to national marine resources development

A review is presented of the various marine resources and their potential, concerning fishing, aquaculture, transportation, pollution, hydrocarbons and solid minerals, renewable energy and ocean thermal energy conversion. Administrative problems confronting their rational management in Sri Lanka are examined, considering coastal area management and development, management issues, and alternatives

Temperature dependence of second-order nonlinear relaxation of a poled chromophore doped sol-gel material

International audienceSecond-order optical nonlinearity relaxations of hybrid inorganic/organic sol-gel films doped with poled Disperse Red 1 chromophores were measured by second harmonic generation at several temperatures. The decay curves were fitted to biexponentials and Ko¨hlrausch, Williams, and Watts ~KWW! stretched exponentials. It can be concluded that the KWW model well describes chromophore thermal reorientation in hybrid sol-gel materials, as is known for all-organic polymers. Using the Arrhenius law, the activation energy of the reorientation process has been determined to be about 50 or 70 kcal mol21. A stability of roughly a decade has been extrapolated at room temperature. Another experiment at room temperature gave an estimation of the stability that was found to be in qualitative agreement. It is shown that poled chromophore-doped sol-gel materials have the potential to be stable enough for applications in telecommunication device

Global Burden Related to Nitrous Oxide Exposure in Medical and Recreational Settings: A Systematic Review and Individual Patient Data Meta-Analysis.

The risk of adverse effects of nitrous oxide (N2O) exposure is insufficiently recognized despite its widespread use. These effects are mainly reported through case reports. We conducted an individual patient data meta-analysis to assess the prevalence of clinical, laboratory, and magnetic resonance findings in association with N2O exposure in medical and recreational settings. We calculated the pooled estimates for the studied outcomes and assessed the potential bias related to population stratification using principal component analysis. Eighty-five publications met the inclusion criteria and reported on 100 patients with a median age of 27 years and 57% of recreational users. The most frequent outcomes were subacute combined degeneration (28%), myelopathy (26%), and generalized demyelinating polyneuropathy (23%). A T2 signal hyperintensity in the spinal cord was reported in 68% (57.2-78.8%) of patients. The most frequent clinical manifestations included paresthesia (80%; 72.0-88.0%), unsteady gait (58%; 48.2-67.8%), and weakness (43%; 33.1-52.9%). At least one hematological abnormality was retrieved in 71.7% (59.9-83.4%) of patients. Most patients had vitamin B12 deficiency: vitamin B12 <150 pmol/L (70.7%; 60.7-80.8%), homocysteine >15 µmol/L (90.3%; 79.3-100%), and methylmalonic acid >0.4 µmol/L (93.8%; 80.4-100%). Consistently, 85% of patients exhibited a possibly or probably deficient vitamin B12 status according to the cB12 scoring system. N2O can produce severe outcomes, with neurological or hematological disorders in almost all published cases. More than half of them are reported in the setting of recreational use. The N2O-related burden is dominated by vitamin B12 deficiency. This highlights the need to evaluate whether correcting B12 deficiency would prevent N2O-related toxicity, particularly in countries with a high prevalence of B12 deficiency

Exploring the Influence of Price and Convenience on Perceived Usefulness of On-line Banking within the TAM Framework: A Cross National (Canada and Spain) Decision Model

Nowadays, the Internet is a powerful mean to complement the traditional marketing channels used by banks. Based on the Technology Acceptance Model, this paper explores the importance of two external latent variables—‘Price’ and ‘Convenience’ —as antecedents of ‘Perceived Usefulness’ and consumer acceptance of on-line banking in a Canadian and Spanish environment; the results highlight the predictive power and accuracy of the model cross-nationally. In fact, the findings were quite similar in the Canadian and Spanish samples, and stress that ‘Perceived Usefulness’ and ‘Attitude’ are the key drivers of the consumers’ on-line banking acceptance. Conclusions and recommendations for future research are also provided

Stable photorefractive memory effect in sol-gel materials

International audienceWe report on the synthesis and the optical characterization of a photorefractive sol-gel material which contains nonlinear azo chromophore and carbazole charge transporting molecules. Both of these functional groups are covalently attached to the silica based backbone. Thin sol-gel films exhibit stable optically nonlinear properties: the electro-optic coefficient r13 measured at 633 nm is found to be 17 pm/V one day after corona poling and 15 pm/V after three weeks and over a period of several months. Photorefractivity is demonstrated by two beam coupling experiments without external applied electric field. Sol-gel films present a stable photorefractive memory effect with a net internal gain of 200 cm-

Full abstraction for sequential languages : The states of the art

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