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The analysis of the accurate topo-bathymetric digital elevation model (DEM), the cartography of the submarine sedimentary cover and the monitoring of short (seasonal) and medium-term (2000-2009) morphological changes have permitted depicting the erosional trend in the short and medium-term of the Maspalomas sedimentary system. Short-term analysis showed intense sedimentary fluxes between the beaches and the inner shelf, and sedimentary exchanges with other sectors of the inner shelf, while the steep slope inner shelf fronting La Bajeta cape was identified as a sink area. In the medium-term the sediment budget showed high erosion of the supratidal and intertidal sectors of the beaches due to storm waves in the 2005-2006 winter, followed by accretion over the next four years, but which did not reach the initial sedimentary state. The inner shelf and subtidal sector of the beaches showed negative budgets in the short and medium-term. Interannual variability of the wave and wind regimes determines decadal beach erosion-accretion cycles, while long-term climatic change, evidenced at the study area by a decrease of trade winds and NE wave intensity in 2005, is expected to produce a possible increase of erosion at the El Inglés inner shelf and consequently a decrease in sediment inputs to the El Inglés beach and Maspalomas dune field. Finally, the influence of the geological heritage is depicted by the Fataga gully's control of the present coastal morphology, and by the island relief control of the wind, waves and current directions in the study area.

Environmental licensing is the regulatory procedure that enforces the environmental impact assessment (EIA) of human activities inside a given country. Despite worldwide acceptance of EIA as a valid tool, its application in coastal environments is still too diverse and limited regarding the specificity of the natural processes influencing the shore. This paper compares the Environmental Licensing Procedure (ELP) of four countries, focusing on the activities that could affect the coastal geomorphology. The acquisition and validation of information were done through interviews with EIA representatives in each country, who signalized the official documents of environmental licensing and coastal management to be considered in the documentary review. The results present those differences and similarities among ELP stages in each country, based on the principles of the International Association of Impact Assessment and the national documents analyzed. In sum, 59 interventions associated with human uses and activities in the coastal zone were compared according to the prescriptive character of the environmental licensing in Italy, Spain, Cuba and Colombia. The natural processes influencing coastal geomorphology were also analyzed within the technical criteria included in the official guidelines for the EIA, finding a generalized weakness in processes associated with geochemical courses on coastal environments. By way of discussion, seven good practices are illustrated, according to their pertinence to the impact assessment of the coastal zone: 1) The integration of screening and scoping; 2) Evaluation focusing on the environment rather than the intervention; 3) Binding the coastal zone delimitation; 4) Institutional articulation; 5) Accreditation of environmental consultancies; 6) Official guidelines by types of environment; 7) The integration of environmental geographic information. Finally, general conclusions to assist EIA practitioners operating in the four countries a

This study evaluated patterns of coastal sediment movement and deposition under different seasonal conditions (warm and cold phases of the El Nino-Southern Oscillation [ENSO] and normal conditions) in Cartagena Bay, Colombia. A calibrated numerical model (MOHID modeling system) was applied to assess the spatial distribution of sediments transported by the Canal del Dique to the bay and studied the spatial distribution and major textural characteristics of 234 surface sediment samples. Currents in the Bay of Cartagena are controlled primarily by the strength and direction of the wind. Model results show major sediment deposition in the southern sector of the bay during the dry season. More homogenous spatial distribution of sediments throughout the Bay of Cartagena occurs with an increase in river inputs from the Canal del Dique. These patterns were enhanced or weakened, respectively, by cold and warm phases of the ENSO. Predominant sediments were medium size (phi = 5.35 +/- 1.2), poorly sorted (sigma = 1.63 +/- 0.8), with notable asymmetry (Sk = -0.052 +/- 0.2) and kurtosis (k = 0.84 +/- 0.4). Sediments with lower sand content (<5%) are located along a latitudinal axis from the Canal del Dique delta to the western end of the island of Tierrabomba. CaCO3 content of the sediments is <10%. Water and sediment flow, controlled by the Canal del Dique, has favored the transport and deposition of poorly sorted, symmetric, and mesokurtic mud in most of the Bay of Cartagena. As a result, autogenous calcareous sediments have been covered by fine terrigenous sediments that were delivered via the Canal del Dique. Thus, the channel plays a more prominent role in sediment transport and deposition in the Bay of Cartagena than thought previously.

Concreting the natural shoreline by use of traditional hard protective structures, as well as by port/harbour developments is commonly known as coastal armouring. Over the recent decades the expanding level of coastline hardening and its adverse impacts on the environment has arisen as one of the most critical problems all over the world. Therefore, our goal in this study was to demonstrate the crucial issue of progressive extent of technogenous coastal occupation by two case studies from different countries in Europe and in South America: Bulgaria and Colombia. To assess direct impact of armouring on the coastline and adjacent areas two case areas were selected for detailed investigation: an 18 km long coastline of the large Varna Bay (Bulgarian Black Sea coast) and 349 km long littoral of the Cartagena municipality (Caribbean coastline of Colombia). An indicative coastal segmentation of the both case sites by geomorphologic and engineering criteria was first implemented in GIS environment. As well as, for quantitative assessment of the influence of all maritime structures (port and coast-protection) on the studied coasts the coefficient of technogenous impact K was explored. A GIS methodology was applied for data processing, mapping the natural landforms/structures and to evaluate the technogenous impact on the both coastlines. The identified high extent of impacts due to built hard defence structures along the selected study areas in Bulgaria and Colombia could be considered as indicative of the large technogenous occupation of the coasts and the increasing level of shoreline armouring as a global issue.

Histidine-containing dipeptides (HCDs) are abundantly expressed in striated muscles. Although important properties have been ascribed to HCDs, including H+ buffering, regulation of Ca2+ transients and protection against oxidative stress, it remains unknown whether they play relevant functions in vivo. To investigate the in vivo roles of HCDs, we developed the first carnosine synthase knockout (CARNS1−/−) rat strain to investigate the impact of an absence of HCDs on skeletal and cardiac muscle function. Male wild-type (WT) and knockout rats (4 months-old) were used. Skeletal muscle function was assessed by an exercise tolerance test, contractile function in situ and muscle buffering capacity in vitro. Cardiac function was assessed in vivo by echocardiography and cardiac electrical activity by electrocardiography. Cardiomyocyte contractile function was assessed in isolated cardiomyocytes by measuring sarcomere contractility, along with the determination of Ca2+ transient. Markers of oxidative stress, mitochondrial function and expression of proteins were also evaluated in cardiac muscle. Animals were supplemented with carnosine (1.8% in drinking water for 12 weeks) in an attempt to rescue tissue HCDs levels and function. CARNS1−/− resulted in the complete absence of carnosine and anserine, but it did not affect exercise capacity, skeletal muscle force production, fatigability or buffering capacity in vitro, indicating that these are not essential for pH regulation and function in skeletal muscle. In cardiac muscle, however, CARNS1−/− resulted in a significant impairment of contractile function, which was confirmed both in vivo and ex vivo in isolated sarcomeres. Impaired systolic and diastolic dysfunction were accompanied by reduced intracellular Ca2+ peaks and slowed Ca2+ removal, but not by increased markers of oxidative stress or impaired mitochondrial respiration. No relevant increases in muscle carnosine content were observed after carnosine supplementation. Resu

Tourism is one of the fastest growing activities in Colombia; the coast represents the favourite destination for both national and foreign visitors. However, coastal erosion is an actual problem, with high erosive rates in some areas. This chapter shows a general overview of the coastal erosion problem in Colombia and emphasizes the institutional framework used in monitoring. Four study cases are included to present a wide diagnosis of relevant erosive processes, both on Caribbean and Pacific coasts. Findings show erosive rates due to human interventions in all coastal departments on the Caribbean Sea; highest values were recorded in Cordoba (3.3 m/yr), Magdalena (5.3 m/yr) and La Guajira (3.2 m/yr). In addition, monitoring of barrier islands indicated that erosive processes on the Pacific coast are essentially due to natural phenomena, i.e. tsunami and El Niño events. In conclusion, long-term coastal erosion monitoring is urgently required in order to make adequate decisions and assess their effectiveness, with special concern to the correct location of coastal infrastructure and the management of coastal risks.

This study provides the coastal scenery assessment of 135 sites along the Colombian Caribbean littoral by analysing 26 physical and human factors. Sites were categorised into five classes from Class 1, top grade scenery, to Class 5, poor scenery. Fifty five percent of the investigated coastal areas were included in Classes 1 and 2, 18% belonged to Class 3 and 47% of the sites fall into Classes 4 and 5. Classification of analysed sites depends on the geological setting and the degree of human occupation. Classes 1 and 2 sites are located in natural protected areas in La Guajira and Magdalena departments. Low classification recorded at Classes 3, 4 and 5 corresponds to a progressive decrease of both natural and (especially) human parameters. Concerning coastal management issues, emphasis should be given to the upgrading of human parameters eliminating litter and sewage evidences, vegetation debris and enhancing beach nourishment works

Los planes de desarrollo planteados para el litoral pacífico colombiano consideran, entre otro aspectos, la constucción de puertos, vias ferreas, carreteras de penetración, complejos industriales y turísticos, y aprovechamientos intensivos de acuicultura y pesca.

Los planes de desarrollo planteados para el litoral pacífico colombiano consideran, entre otro aspectos, la constucción de puertos, vias ferreas, carreteras de penetración, complejos industriales y turísticos, y aprovechamientos intensivos de acuicultura y pesca.

Four antigenic sites of the E2 glycoprotein of transmissible gastroenteritis virus were defined by competitive radioimmunoassays of monoclonal antibodies (MAbs). Here, we describe the localization of these sites by testing the antigenicity of protein fragments and prokaryotic expression products of E2 gene fragments, and by sequencing of MAb-resistant (mar) mutants. Partial proteolysis of purified E2 protein allowed the isolation of a 28K fragment recognized by both site A- and site C-specific MAbs. An antiserum against this fragment bound to a synthetic peptide containing residues 1 to 18 and to an expression product containing residues 1 to 325. The same expression product was recognized by site C-specific MAbs. These data indicate that residues within the sequence 1 to 325 contribute to site C and possibly also to site A. Sequencing of mar mutants that escaped neutralization by site A-specific MAbs indicated that residues 538 and 543 also belong to site A. The binding of site-specific MAbs to expression products led directly to the localization of sites B and D, between residues 1 to 325 and 379 to 529, respectively. The first 37% of the polypeptide chain of E2 appears to be more immunogenic than the rest of the sequence.

The antigenic homology of 26 coronavirus isolates, of which 22 were antigenically related to transmissible gastroenteritis virus (TGEV), was determined with 42 monoclonal antibodies. Type, group, and interspecies specific epitopes were defined. Two group specific MAbs distinguished the enteric TGEV isolates from the respiratory variants. An antigenic subsite involved in neutralization was conserved in porcine, feline, and canine coronavirus. The classification of the human coronavirus 229E in a taxonomic cluster distinct from TGEV group is suggested. © 1990.