237 research outputs found
Application Of A Decision Support System For The SustainablePlanning Of Rio Pojuca Basin (Bahia, Brazil) Water Resources
The paper presents the structure and the application of a Decision Support System (DSS) to Pojuca
River watershed placed in the Northeast Region of Brazil (Bahia State).
It is composed of surface-water quality models (total phosphorus, BOD, dissolved oxygen
concentration and thermo-tolerant coliform bacteria pollution). A model evaluates the riverine
microhabitat applying autochthonous fish species habitat suitability indexes (water depth, velocity,
substrate and dissolved oxygen) valuated by local ichthyologists. Surface-water quality and
microhabitat models are based on a hydrologic and hydraulic model. Models have been calibrated
and validated using discharge and water quality measurements collected during a 1.5-year period
of monitoring. Output data are available on a spreadsheet and ready to be spatially analyzed in a
GIS software.
We show how DSS can help the decision-making process to achieve the sustainable development
of the basin, considering population growth, economic activities, climate change, management of
sewage and wastewater treatment systems. The DSS is also applied to a challenging scenario: the
building of an in series reservoir for supplying the Capital (Salvador) of drinking water.
The experience has been characterized also by a large involvement of local specialists, with the
aim to emphasize the existing qualifications and to consider local culture
Snow Accumulation in the Talos Dome Area: Preliminary Results
Determining snow accumulation is one of the principal challenges in mass balance studies and in the interpretation of ice core records. Accurate knowledge of the spatial distribution of snow accumulation is fundamental for understanding the present mass balance and its implication on sea level change, for reliable numerical simulation of past and future ice sheet dynamics, and for creating atmospheric climate models. Depth-age models for deep ice cores require knowledge of the temporal variability of snow accumulation. Accumulation of snow principally results from precipitation of snow and its redistribution/ablation by wind at the surface (Frezzotti et al., 2004a). Chemical and isotopic analysis of ice cores reveals seasonal and annual signals. However, these signals may not be representative of
annual snow accumulation or of the annual chemical/isotopic composition of snow.
Talos Dome (TD, 72°48’S; 159°06’E, 2316 m, T -41.0 °C) is an ice dome on the edge of the East Antarctic plateau, about 290 km from the Southern Ocean and 250 km from the Ross Sea (Fig. 1). An ice core is currently being drilled at this site (Frezzotti et al., 2004b) within the framework of the Talos Dome Ice Core Project (TALDICE). In order to provide detailed information on the temporal and spatial variability of snow accumulation, research was conducted at Talos Dome and
along a North-South transect (GV7-GV5-TD-31DPT) in the framework of the ITASE programme. The 400 km-long transect follows the ice divide from the Southern
Ocean to Talos Dome, and then continues in a southward direction towards Taylor Dome. Stake network measurements, ice core analysis and snow radar surveys along the transect have provided detailed information for reconstructing the temporal (annual) and spatial (meter scale) variability of snow accumulation over the last 200 years at the km scale
TALOS Dome Migration: Preliminary Results
Ice divide-dome migration is a key parameter in mass balance studies and in the interpretation of ice cores. The stability of the dome and position of the ice divide must be known to accurately interpret ice core records and to complete mass balance studies. Models of depth-age relationships for deep ice cores are sensitive to migration of the dome position (Anandakrishnan et al., 1994). The evolution of an ice divide is driven by the accumulation-rate history, its spatial pattern and conditions at ice-sheet boundaries (e.g. Frezzotti et al., 2004; Hindmarsh, 1996; Nereson et al., 1998). Ice divide migration is also important in determining the input parameter of large Antarctic drainage basins. Due to the very low slope (less than a decimetre per km) of East Antarctic domes and to surface morphology (e.g. sastrugi), it is very difficult to determine the summit point of a dome and its migration in time. In 2004 a new ice coring project, TALDICE (Talos Dome Ice
Core Project), started at TD to recover 1550 m of ice spanning the last 120 000 years (Frezzotti et al., 2004). This paper discusses preliminary findings on the present and past morphology of Talos Dome based on detailed snow accumulation data, radar-derived isochrons and ice velocity measurements in the last 10 years
Fast geophysical prospecting applied to archaeology: results at «Villa ai Cavallacci» (Albano Laziale, Rome) site
The present essay is the result of a cooperative work between geophysicists and archaeologists in which the authors
carried out an integrated geophysical prospecting in an archaeological site near Rome. This paper describes the
methodology and the results of a geophysical survey carried out on Villa ai Cavallacci, an ancient roman building in
Albano Laziale (Rome) discovered in the late seventies. It is often possible to obtain very important results planning
a fast geophysical survey opportunely; within this framework (due to the fact that an archaeological excavation was
planned in a short time), an integrated geophysical techniques survey (GPR, magnetic, and geoelectric tomography)
has been carried out on the areas indicated by the archaeologists. Even if the described geophysical survey should be
considered only a first step analysis, the data pointed out some very interesting features confirmed by the excavation
Assessment of biological kinetics in a conventional municipal WWTP by means of the oxygen uptake rate method
Pollution control of surface water bodies requires stringent checks on wastewater treatment plants performances. The satisfactory operation of biological treatment, commonly performed by means of activated sludge processes, requires a number of controlling and monitoring procedures. Suitable respirometric techniques for the determination of the kinetic parameters that regulate biological processes have been implemented in order to achieve this aim. This paper describes the results of an experimental research carried out in a conventional Italian municipal wastewater treatment plant. Particularly, the research has been finalized to both evaluate the biological process for the removal of biodegradable pollutants, such as carbonaceous substrates and ammonia nitrogen, and to collect data in order to evaluate a possible plant upgrade. Heterotrophic and autotrophic biomass kinetic parameters have been examined using respirometric techniques based on oxygen uptake measurements. The research performed makes a valuable contribution toward verifying the reliability of the values proposed in the literature for some kinetic parameters, which have been commonly used for a long time
Recovery of different waste vegetable oils for biodiesel production: a pilot experience in Bahia State, Brazil
In Brazil, and mainly in the State of Bahia, crude vegetable oils are widely used in the preparation of food. Street stalls, restaurants and canteens make a great use of palm oil and soybean oil. There is also some use of castor oil, which is widely cultivated in the Sert\ue3o Region (within the State of Bahia), and widely applied in industry. This massive use in food preparation leads to a huge amount of waste oil of different types, which needs either to be properly disposed of, or recovered. At the Laboratorio Energia e Gas-LEN (Energy & Gas lab.) of the Universidade Federal da Bahia, a cycle of experiments were carried out to evaluate the recovery of waste oils for biodiesel production. The experiences were carried out on a laboratory scale and, in a semi-industrial pilot plant using waste oils of different qualities. In the transesterification process, applied waste vegetable oils were reacted with methanol with the support of a basic catalyst, such as NaOH or KOH. The conversion rate settled at between 81-85% (in weight). The most suitable molar ratio of waste oils to alcohol was 1:6, and the amount of catalyst required was 0.5% (of the weight of the incoming oil), in the case of NaOH, and 1%, in case of KOH.
The quality of the biodiesel produced was tested to determine the final product quality. The parameters analyzed were the acid value, kinematic viscosity, monoglycerides, diglycerides, triglycerides, free glycerine, total glycerine, clearness; the conversion yield of the process was also evaluated
Location of a new ice core site at Talos Dome (East Antarctica)
In the frame of glaciology and palaeoclimate research, Talos Dome (72°48lS; 159°06lE), an ice dome on the East
Antarctic plateau, represents the new selected site for a new deep ice core drilling. The increasing interest in this region
is due to the fact that the ice accumulation is higher here than in other domes in East Antarctica. A new deep
drilling in this site could give important information about the climate changes near the coast. Previous papers
showed that the dome summit is situated above a sloped bedrock. A new position on a relatively flat bedrock 5-6 km
far from here in the SE direction was defined as a possible new ice core site for an European (Italy, France, Swiss
and United Kingdom) drilling project named as TALDICE (TALos Dome Ice Core Project). This point, named as
ID1 (159°11l00mE; 72°49l40mS), became the centre of the Radio Echo Sounding (RES) flight plan during the 2003
Italian Antarctic expedition, with the aim of confirming the new drilling site choice. In this paper 2001 and 2003 RES
data sets have been used to draw a better resolution of ice thickness, bottom morphology and internal layering of a
restricted area around the dome. Based on the final results, point ID1 has been confirmed as the new coring site. Finally,
the preliminary operations about the installation of the summer ice core camp (TALDICE) at ID1 site carried
out during the XX Italian Antarctic expedition (November 2004-December 2005) are briefly described
18F-FDG-PET/CT imaging in cardiac tumors: illustrative clinical cases and review of the literature.
Cardiac tumors are a very rare condition. Mostly, they are benign tumors (75%), with myxomas being the most frequent. The remaining 25% are malignant; either primary malignant sarcoma or secondary metastases. Given the small number of cases reported and the lack of prospective and randomized clinical trials, the level of evidence for the optimal multimodal treatment of primary cardiac sarcomas is very low and the optimal imaging diagnostic workup is not well established. In particular, 18F-FDG-PET/CT is not yet included in routine diagnosis of cardiac masses. Here, we report four illustrative clinical cases and a review of the literature on the current available data on the role of 18F-fluorodeoxyglucose PET/CT imaging in cardiac tumors
A synthesis of the Antarctic surface mass balance during the last 800 yr
Global climate models suggest that Antarctic snowfall should increase in a warming climate and mitigate rises in the sea level. Several processes affect surface mass balance (SMB), introducing large uncertainties in past, present and future ice sheet mass balance. To provide an extended perspective on the past SMB of Antarctica, we used 67 firn/ice core records to reconstruct the temporal variability in the SMB over the past 800 yr and, in greater detail, over the last 200 yr. <br><br> Our SMB reconstructions indicate that the SMB changes over most of Antarctica are statistically negligible and that the current SMB is not exceptionally high compared to the last 800 yr. High-accumulation periods have occurred in the past, specifically during the 1370s and 1610s. However, a clear increase in accumulation of more than 10% has occurred in high SMB coastal regions and over the highest part of the East Antarctic ice divide since the 1960s. To explain the differences in behaviour between the coastal/ice divide sites and the rest of Antarctica, we suggest that a higher frequency of blocking anticyclones increases the precipitation at coastal sites, leading to the advection of moist air in the highest areas, whereas blowing snow and/or erosion have significant negative impacts on the SMB at windy sites. Eight hundred years of stacked records of the SMB mimic the total solar irradiance during the 13th and 18th centuries. The link between those two variables is probably indirect and linked to a teleconnection in atmospheric circulation that forces complex feedback between the tropical Pacific and Antarctica via the generation and propagation of a large-scale atmospheric wave train
Geomagnetic field observations at a new Antarctic site, within the AIMNet project
During the 2007-2008 antarctic campaign, the Italian PNRA installed a Low Power Magnetometer within the
framework of the AIMNet (Antarctic International Magnetometer Network) project, proposed and coordinated
by BAS. The magnetometer is situated at Talos Dome, around 300 km geographically North-West from Mario
Zucchelli Station (MZS), and approximately at the same geomagnetic latitude as MZS. In this work we present a
preliminary analysis of the geomagnetic field 1-min data, and a comparison with simultaneous data from different
Antarctic stations
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