Tourism competitiveness in the Caribbean

Includes bibliography

Experimental Study on Friction between Saline Ice and Steel

Understanding the interaction of sea ice with offshore structures is of primary importance for the development of technology in cold climate regions. The rheological properties of sea ice (strength, creep, viscosity) as well as the roughness of the contact surface are the main factors influencing the type of interaction with a structure. A device was developed and designed and small scale laboratory experiments were carried out to study sea ice frictional interaction with steel material by means of a uniaxial compression rig. Sea-ice was artificially grown between a stainless steel piston (of circular cross section) and a hollow cylinder of the same material, coaxial to the former and of the same surface roughness. Three different values for the roughness were tested: 1.2, 10 and 30 μm Ry (maximum asperities height), chosen as representative values for typical surface conditions, from smooth to normally corroded steel. Creep tests (0.2, 0.3, 0.4 and 0.6 kN) were conducted at T = -10 ºC. By pushing the piston head towards the cylinder base, three different types of relative movement were observed: 1) the piston slid through the ice, 2) the piston slid through the ice and the ice slid on the surface of the outer cylinder, 3) the ice slid only on the cylinder surface. A cyclic stick-slip motion of the piston was detected with a representative frequency of 0.1 Hz. The ratio of the mean rate of axial displacement to the frequency of the stick-slip oscillations was found to be comparable to the roughness length (Sm). The roughness is the most influential parameter affecting the amplitude of the oscillations, while the load has a relevant influence on the their frequency. Guidelines for further investigations were recommended. Marco Nanetti - seloselo@virgilio.it

Cytochrome P450 inhibitory action of Echinacea preparations differs widely and co-varies with alkylamide content

Echinacea preparations are one of the best selling herbal medicinal products with a well established therapeutic use in the prophylaxis of upper respiratory tract infections. Their consumption is increasing, but information about their ability to inhibit cytochrome P450 enzymes (CYP) is fragmentary. The picture is further complicated by a lack of phytochemical characterization of previously tested preparations. Due to its well characterized immunomodulatory activity, the standardized Swiss registered Echinacea purpurea (L.) Moench Echinaforce extract was selected for detailed study. With the single baculovirus-expressed CYP isoforms 1A2, 2C19, 2D9 and 3A4, inhibitory actions were measured by monitoring fluorescent metabolites derived from enzyme substrates (supersome assay). The Echinaforce extract induced mild inhibition of all these isoforms, with CYP 3A4 being the most, and CYP 2D6 the least sensitive enzyme. To assess whether CYP inhibition might be a general feature of Echinacea preparations, an additional nine commercially available preparations were screened using CYP 3A4. All tested preparations were able to inhibit CYP 3A4, but inhibitory potencies (expressed as median inhibitory concentration, IC50) varied by a factor of 150. The alkylamides are thought to be responsible for the immunomodulatory activity of Echinacea, and so the concentration of 2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and total alkylamide content were determined in all preparations, and the latter was found to be associated with their CYP 3A4 inhibitory potency. The chemically pure alkylamides dodeca-2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and dodeca-2E,4E-dieonoic acid isobutylamide (2) showed inhibitory activity on CYP 2C19, 2D6 and 3A4. However, unlike the Echinaforce extract, the alkylamides did not induce CYP 1A2 inhibition. Thus, other, as yet unidentified constituents also contribute to the overall weak inhibitory effects seen with Echinacea preparations in-vitro.

Cannabinoid receptor ligands as potential anticancer agents--high hopes for new therapies?

OBJECTIVES: The endocannabinoid system is an endogenous lipid signalling network comprising arachidonic-acid-derived ligands, cannabinoid (CB) receptors, transporters and endocannabinoid degrading enzymes. The CB(1) receptor is predominantly expressed in neurons but is also co-expressed with the CB(2) receptor in peripheral tissues. In recent years, CB receptor ligands, including Delta(9)-tetrahydrocannabinol, have been proposed as potential anticancer agents. KEY FINDINGS: This review critically discusses the pharmacology of CB receptor activation as a novel therapeutic anticancer strategy in terms of ligand selectivity, tissue specificity and potency. Intriguingly, antitumour effects mediated by cannabinoids are not confined to inhibition of cancer cell proliferation; cannabinoids also reduce angiogenesis, cell migration and metastasis, inhibit carcinogenesis and attenuate inflammatory processes. In the last decade several new selective CB(1) and CB(2) receptor agents have been described, but most studies in the area of cancer research have used non-selective CB ligands. Moreover, many of these ligands exert prominent CB receptor-independent pharmacological effects, such as activation of the G-protein-coupled receptor GPR55, peroxisome proliferator-activated receptor gamma and the transient receptor potential vanilloid channels. SUMMARY: The role of the endocannabinoid system in tumourigenesis is still poorly understood and the molecular mechanisms of cannabinoid anticancer action need to be elucidated. The development of CB(2)-selective anticancer agents could be advantageous in light of the unwanted central effects exerted by CB(1) receptor ligands. Probably the most interesting question is whether cannabinoids could be useful in chemoprevention or in combination with established chemotherapeutic agents.

High Albania and its customs in 1908 /

Reprinted from the Journal of the Royal Anthropological Institute, vol XL.

Coates's herd book.

Vols. - include the Shorthorn Society's Grading register for beef Shorthorn cattle; v. - include the society's Herd book of poll shorthorns.

Sea-power, and other studies,

Ten of the essays included in this volume first appeared in the Encyclopaedia britannica, the Times, the Morning post, the National review, the Nineteenth century and after, the Cornhill magazine, and the Naval annual ... The paper on "Naval strategy and tactics at the time of Trafalgar" was read at the Institute of naval architects, and that on "The supply and communications of a fleet" at the Hong-Kong United service institution.

Indian antiquary.

Vols. 14-62 called also ser. 2.

The history of the Jews : from the earliest period down to modern times /

Original in the Princeton Theological Seminary.

Transactions.

Numbering for v.56 is supplied. Title page reads: Supplemental volume, containing I. Chapter of incorporation, II. Address of Council, III. Papers read to the society during the sessions 1846-7, 1847-8. London, 1852.

The ecclesiastical and architectural topography of England ...

Diocese of Oxford.--Diocese of Ely.

Lettres sur les peintures, sculptures et gravures de Mrs. de l'Académie royale : exposées au Sallon du Louvre depuis MDCCLXVII jusqu'en MDCCLXXIX /

Cicognara,

Museum rusticum et commerciale; or, Select papers on agriculture, commerce, arts, and manufactures.

Mode of access: Internet.

Memoranda of a residence at the court of London.

A second series was pub. in 1845 by Lea & Blanchard, Philadelphia, under title "Memoranda of a residence at the court of London, comprising incidents official and personal from 1819 to 1825. Including negotiations on the Oregon question, and other unsettled questions between the United States and Great Britain;" also in London by R. Bentley (in 2 vols.) with title slightly changed. The 2d ed. of this series appeared in London, R. Bentley, 1873, under title: The court of London from 1819 to 1825.

Remarks on the Zend language and the Zendavesta. In a letter from the late Professor Emanuel Rask to the Honourable Mountstuart Elphinstone then President of the Literary Society at Bombay.

Signed E. Rask.