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Various lung ultrasound (LUS) scanning modalities have been proposed for the detection of B-lines, also referred to as ultrasound lung comets , which are an important indication of extravascular lung water at rest and after exercise stress echo (ESE). The aim of our study was to assess the lung water spatial distribution ( comet map ) at rest and after ESE. We performed LUS at rest and immediately after semi-supine ESE in 135 patients (45 women, 90 men; age 62 ± 12 y, resting left ventricular ejection fraction = 41 ± 13%) with known or suspected heart failure or coronary artery disease. B-lines were measured by scanning 28 intercostal spaces (ISs) on the antero-lateral chest, 2nd–5th IS, along with the midaxillary (MA), anterior axillary (AA), mid-clavicular (MC) and parasternal (PS) lines. Complete 28-region, 16-region (3rd and 4th IS), 8-region (3rd IS), 4-region (3rd IS, only AA and MA) and 1-region (left 3rd IS, MA) scans were analyzed. In each space, the B-lines were counted from 0 = black lung to 10 = white lung. Interpretable images were obtained in all spaces (feasibility = 100 %). B-lines (>0 in at least 1 space) were present at ESE in 93 patients (69%) and absent in 42. More B-lines were found in the 3rd IS and along AA and MA lines. The B-line cumulative distribution was symmetric at rest (right/left = 1.10) and asymmetric with left lung predominance during stress (right/left = 0.67). The correlation of per-patient B-line number between 28-S and 16-S (R 2 = 0.9478), 8-S (R 2 = 0.9478) and 4-S scan (R 2 = 0.9146) was excellent, but only good with 1-S (R 2 = 0.8101). The average imaging and online analysis time were 5 s per space. In conclusion, during ESE, the comet map of lung water accumulation follows a predictable spatial pattern with wet spots preferentially aligned with the third IS and along the AA and MA lines. The time-saving 4-region scan is especially convenient during stress, simply dismissing dry regions and focusing on wet regions alone.

Geothermal resource evaluation was accomplished for the Baja California Peninsula hydrothermal systems. Numerous geothermal areas were identified along the eastern coast of the Peninsula, which are related with the Gulf of California opening process. The western coast presents hydrothermal activity in the northern part related with regional faults like the Agua Blanca Fault nearby Ensenada. The southern part of the Peninsula also has abundant geothermal resources related with local grabens. The heat in place evaluation was accomplished for five geothermal areas where geophysical data were available to estimate the reservoir volume. The minimum calculated potential is more than 400 MWe. There are still more than six geothermal prospects with calculated temperatures above 200 °C that lack reliable information on the reservoir volume and would increase the geothermal potential of the Peninsula. Surface heat loss from the submarine systems reaches more than 6000 MWt.

A primary aim for sampling of submarine hydrothermal vents is to minimize inclusion of ambient seawater. Here, we compare the results of three different sampling methods (air displacement, two-valve bottle, and syringes) for shallow submarine systems. Mixing of hydrothermal fluid with seawater is unavoidable; however, calculations based on linear mixing models allow estimation of the hydrothermal fluid end-member composition. The results show that sampling with a two-valve bottle and syringes are the best options because they allow collection of samples with a large proportion of hydrothermal fluid. Additionally, we compare the results of in situ and laboratory analyses of the fluid samples, and demonstrate that determination of chemical composition in situ is the best option for some components, as re-equilibration affects some component concentrations (i.e. bicarbonate). Conversely, silica determination in situ usually underestimates the concentration in the fluid, as it does not account for polymeric silica. Other components can be measured either in the field or in the laboratory.

This work investigated the mechanisms involved in the “in vitro” calcification of chitosan films. The calcification process on chitosan films is a phenomenon that has not been sufficiently studied, despite its importance in the understanding of many natural processes, such as bone and shell formation. Three different techniques were used in the present investigation: X-ray fluorescence (XRF), atomic force microscopy (AFM) and X-ray diffraction (XRD). Natural and acetylated chitosan films were used as substrates for calcification. The experiments were carried out by immersing chitosan membranes in simulated body fluid (SBF) or in a modified version of SBF, prepared without phosphate ions, during 30 min, 3 or 12 h. Calcium maps obtained by XRF showed that the initial calcium distribution on the chitosan surface was influenced by the acetylation treatment of chitosan films. AFM indicated the distribution pattern of calcium compound deposits at different times, obtained by film surface morphological analysis. The results suggest that the calcification mechanism is nucleation on membranes followed by the crystal growth of calcium compounds. AFM showed that the deposit formation is a function of immersion time: the deposits became more homogeneous and covered the surface more evenly with longer immersion times. XRD showed that the acetylated membranes produced more organized calcium deposits.

Coastal submarine hydrothermal venting occurs on the west shore of the fault-bounded bay of Bahia Concepcion, along a stretch of about 700 m of rocky shoreline. Diffuse hydrothermal seepage of water and continuous gas bubbling (mainly CO2 and N2) take place through the sediment-covered seafloor at shallow depth (5 to 15 m). In addition, at about 500 m SE, a cluster of hot springs occurs within the intertidal zone. The temperature and pH of the hydrothermal fluids varies from 72 to 87 °C and 5.95 to 6.02 in the submarine diffuse venting area and reaches 62 °C and pH of 6.68 in the intertidal hot springs. Mn–Ba–Hg mineralization is presently forming as a result of the hydrothermal venting. At the intertidal hot springs, moss-like crusts of manganese oxides and structureless detrital aggregates cemented by opal-A, barite and calcite occur around the main discharge conduits. These aggregates are overlaid by silica-carbonate fine-layered stromatolitic aggregates that extend some meters from the hot springs forming crusts and coalescing rims over volcanic pebbles and boulders. Manganese crusts are made up of barium rich, X-ray-amorphous todorokite-like and romanechite phases, and represent a rare example of a manganese deposit formed in a shallow submarine hydrothermal environment. In the submarine diffuse venting area the hydrothermal precipitates are less conspicuous and consist in millimeter-thick iron oxyhydroxide coatings on volcanic cobbles and boulders. These coatings are composed of poorly crystallized six-line ferrihydrite, accompanied by minor cinnabar and fine-grained colloform pyrite. Textures and fabrics of the mineral assemblages suggest microbial mediation for mineral deposition. The vent precipitates display a significant enrichment of Hg, As and Sb. Arsenic is probably adsorbed onto Mn- and Fe-oxide substrates. The NASC (North American Shale Composite)-normalized REE patterns of the vent precipitates show a pronounced positive Eu anomaly that is probably inherited from the hydrothermal fluid.

An investigation has been made of the response of the Los Azufres geothermal reservoir to 20 years of development, beginning in 1982. The simulator WELFLO was used to characterize the thermodynamic conditions of the reservoir fluids. The first response to exploitation consisted of a decrease in pressure and an increase in enthalpy. Small decreases in reservoir pressure associated with large increases in fluid enthalpy characterize the long-term response in the northern production area. In the southern production area, long-term changes include decreases in pressure and mass flow rate, increases in steam production and, in wells affected by injection, increases in both pressure and total mass flow rate. These changes reflect the effects of boiling, cooling and fluid mixing, processes resulting from large-scale fluid production.

Chitosan membranes with self-organized lines on surface were obtained. SEM and laser diffraction techniques showed that structures with peak-valley periods of about 5 ± 2 μm were observed in both porous and dense chitosan membranes. These unique patterns may be of special interest for applications where micro-mechanical interactions are important such as for biomaterials. The procedure used to produce these membranes consisted of casting, drying of a 2.5% chitosan solution, followed by coagulation using 1.0 M NaOH solution. The analyses indicate that the drying step is the most important to shape the organized surface pattern. This is in agreement with literature that cites that when layers of polymer solutions undergo solvent evaporation and/or heating from below, the interface can become unstable, generating patterns, depending on the surface tension differences and density effects, fluid motion can be generated and amplified, through the known Marangoni effect.

Shallow submarine hydrothermal activity has been observed in the Bahia Concepcion bay, located at the Gulf coast of the Baja California Peninsula, along faults probably related to the extensional tectonics of the Gulf of California region. Diffuse and focused venting of hydrothermal water and gas occurs in the intertidal and shallow subtidal areas down to 15 m along a NW–SE-trending onshore–offshore fault. Temperatures in the fluid discharge area vary from 50 °C at the sea bottom up to 87 °C at a depth of 10 cm in the sediments. Chemical analyses revealed that thermal water is enriched in Ca, As, Hg, Mn, Ba, HCO3, Li, Sr, B, I, Cs, Fe and Si, and it has lower concentrations of Cl, Na, SO4 and Br than seawater. The chemical characteristics of the water samples indicate the occurrence of mixing between seawater and a thermal end-member. Stable isotopic oxygen and hydrogen composition of thermal samples plot close to the Local Meteoric Water Line on a mixing trend between a thermal end-member and seawater. The composition of the thermal end-member was calculated from the chemistry of the submarine samples data by assuming a negligible amount of Mg for the thermal end-member. The results of the mixing model based on the chemical and isotopic composition indicate a maximum of 40% of the thermal end-member in the submarine vent fluid. Chemical geothermometers (Na/Li, Na–K–Ca and Si) were applied to the thermal end-member concentration and indicate a reservoir temperature of approximately 200 °C. The application of K–Mg and Na/Li geothermometers for vent fluids points to a shallow equilibrium temperature of about 120 °C. Results were integrated in a hydrogeological conceptual model that describes formation of thermal fluids by infiltration and subsequent heating of meteoric water. Vent fluid is generated by further mixing with seawater.

The term vulnerability is used as a measure of the damage suffered by a structure due to seismic activity. Vulnerability to ground movement is determined by the structure itself; therefore, the vulnerability of a system does not depend on the local seismic risk. This definition of vulnerability indicates that a structure may be vulnerable in spite of being located in a seismically safe area. Lifeline is an earthquake engineering term denoting those systems necessary for human life and urban function, without which large urban regions cannot exist. Lifelines basically convey food, water, fuel, energy, information, and other materials necessary for human existence from the production areas to the consuming urban areas. Prolonged disruption of lifelines such as the water supply or electric power for a city or urbanized region would inevitably lead to major economic losses, deteriorated public healt, and eventually population migration. Earthquakes are probably the most likely natural disaster that would lead to major lifeline disruption. The adequate operation of lifelines is vital for the economic development of regions under moderate to high seismic activity. After an earthquake, the proper operation of all vital systems is necessary, for instance hospitals for medical attention of the wounded and highways for communication and assistance for victims. In this work we apply the knowledge of pipeline vulnerability to the water supply system, telephone, gas, electricity, sanitary sewer pipelines (waste water), subway, and galleries systems in Barcelona.

A novel algorithm for generating minimal perfect hash tables for large amounts of data is presented. Functions considered are of the form h(key) = g(f1(key)) + f2(key), where g is retrieved from a lookup table, and fi are bit strings contained in the key itself. Since keys are considered as binary strings, and only a few bits from the key itself are used to produce the address in the hash table, search time is independent of the length of the keys and the size of the character set.

Two-dimensional echocardiography was applied experimentally in a closed chest dog model with intact pericardium to determine the location, magnitude and extent of contractile response during pacing from discrete ventricular sites. Mid ventricular short-axis tomographic images obtained during regular sinus rhythm and subsequent premature ventricular beats provided comparative measurements of global and segmental systolic changes of cross-sectional luminal areas and myocardial wall thickness. Computer-assisted standardized analysis of segmental systolic fractional area change and wall thickening was used to map left ventricular contraction during normal rhythm and premature beats of 70% coupling interval, induced alternately from anterior and lateral aspects of the mid-left ventricular short-axis cross-sectional plane. A characteristic pattern consisting of early systolic contraction and wall thickening was followed by paradoxical motion and wall thinning in late systole in segments corresponding to the region of direct electrical stimulation. Statistical analysis of segment by segment function indicated a maximal amount of premature beat contractile derangement at the site of the stimuli. Pacing from a right ventricular wall site in the midventricular plane caused a similar premature beat response at the anterior aspect of the interventricular septum. It is concluded that two-dimensional echographic analysis of segmental ventricular function can identify the location of electrical stimuli, and thus might non-invasively characterize regional patterns of contraction associated with ectopic foci during arrhythmias.