This paper summarizes the Argentine-Brazilian Fast Reactor Programme and gives reasons for the decision of a binational venture. The work carried out by both countries is described, showing how they complement each other, with the corresponding saving of resources. The main objectives of the Programme and tentative schedules in three progressing integrating stages are given and the present nuclear know-how in each country is identified as a good starting point. The paper also gives some details regarding the economical and human resources involved. (author). 1 graph
Full text: A thermal facility for BNCT experiments is being developed in an Argentine Research Reactor: RA-1 'Enrico Fermi'. RA-1 research nuclear reactor is working at Constituyentes Atomic Center, near Buenos Aires, and started operations in 1958. It worked at several power levels, up to 120 k W. Today, RA-1 is licensed to work at 40 k W. RA-1 was used to produce radioisotopes in the early 60's, and today gives irradiation services to test materials, to calibrate detectors and activation analysis. RA-1 users are CNEA researchers, Nuclear Regulatory Authority staff and private laboratories. Boron Neutron Capture Therapy (BNCT) is a method to fight against cancer. It consists to irradiate cancer tumors using thermal neutrons. The tumor tissue should include a dose of a boron solution. The Boron irradiation produces the following nuclear reactions: n + B10→ α + Li7 + γ. Being the α particle a radiation with short range, but high destructive energy, the tumor cells are destroyed. The neutron flux should be of 109 n/cm2seg, and the gamma dose lower than 0.48 s V/h. This method is oriented to treat brain tumors. Taking in account that the brain tumors usually are several centimeters deep in the head, to get thermal neutrons in the tumor is convenient to irradiate the patient using epithermal neutrons. moderation in the cells of the brain will permit to get more thermal neutrons in the tumor. In CNEA BNCT program there is in construction an epithermal clinical facility in the RA-6, a 500 k W research reactor that is at Bariloche Atomic Center. To perform some experiments for instance to test the boron compounds, RA-1 is used. In this experiments little animals like hamsters or bottles with cultivated cells are used, for that reasons thermal neutrons are used. The project in RA-1 consists in several stages. As the first stage a preliminary thermal facility was built. Irradiation times of 45-60 minutes were estimated, at power operation levels of 40 k W. Several
Polenta, Héctor P.; Bernard, John A.; Ray, Asok
The design and implementation of a redundancy management scheme for the on-line detection and isolation of faulty sensors is presented. Such a device is potentially useful in reactor-powered spacecraft for enhancing the processing capabilities of the main computer. The fault detection device can be used as an integral part of intelligent instrumentation systems. The device has been built using an 8-bit microcontroller and commercially available electronic hardware. The software is completely portable. The operation of this device has been successfully demonstrated for real-time validation of sensor data on Argentina's RA-1 Research Reactor.
The design and implementation of a redundancy management scheme for the on-line detection and isolation of faulty sensors is presented. Such a device is potentially useful in reactor-powered spacecraft for enhancing the processing capabilities of the main computer. The fault detection device can be used as an integral part of intelligent instrumentation systems. The device has been built using an 8-bit microcontroller and commercially available electronic hardware. The software is completely portable. The operation of this device has been successfully demonstrated for real-time validation of sensor data on Argentina's RA-1 Research Reactor
Full text: The determination of the quantities dose equivalent H*(10) and personal dose equivalent Hp(10) in mixed field (n,γ) needs the knowledge of the related spectrum. In order to fulfill this aim spectrometer system has been built based on the combination of polyethylene spheres of different diameters (Bonner Spheres System-BSS) and a He3 proportional counter detector sensitive to thermal neutrons. The detector is located in the geometrical centre of each of the spheres and has an associated electronics with a charge preamplifier, an amplifier and a multichannel system that allows the outgoing spectrum analysis. In order to determine the neutron spectrum a deconvolution method is applied based on the LOUHI82 code. In this work are shown the spectra and the related values of H*(10) that have been got in five places of the reactor and in the command room with the BSS. (author)
It is been considered a proposal in order to define a project oriented to modify and to convert the Argentine's research reactor RA6 of 500 KW of thermal power. Its main guidelines are presented here. This reactor is in operation from 1982 in the Bariloche Atomic Center and was designed and constructed by CNEA and INVAP SE. Original core is composed by 25 old design RA3's fuel elements partially burned, that means containing high enriched uranium (HEU). The strategic objective of the project is to allow the use of this facility to produce radioisotopes as auxiliary alternative to the RA3. For these, it is proposed: - to adapt the facility in order to be able to increase the thermal power or neutron flux to adequate level enough to the mentioned use and regarding the compatibility with the general specifications and requiring a minimum of modifications; - to change the core, this implies: - to convert the reactor from HEU to LEU fuel opening the possibility to return spent fuel elements to USA through the RERTR previsions; to include new high density LEU fuels in developing in the country; - to complete the facilities to handle radioactive material in the RA6 building; No major problems are expected considering our long experience acquired with the RA3. Some preliminary studies are already under way. (author)
Reactor vendors in most countries have had lean pickings for the past decade, and ordering seems unlikely to show much growth until the shock wave from the Chernobyl accident has died away. Paradoxically, however, at least one firm sees a niche in the market. ENACE - the Empresa Nuclear Argentina de Centrales Electricas, or Argentine Nuclear Power Plant Corporation - is stepping out into the market place with a newly-designed 380 MWe nuclear power plant. The plant is equipped with a pressurized heavy-water reactor of the pressure vessel type (PHWR). ENACE has adopted new boundary design conditions and has embodied a number of special features to assure safety and economy in operation. The major shareholder in ENACE is the Argentine National Atomic Energy Commission (CNEA). ENACE is the architect-engineer for the NPP projects of the Argentine nuclear programme. It has a licensing agreement with Siemens AG's Kraftwerk Union AG, which is its minor shareholder. Under this agreement, ENACE has the right to use the Siemens-KWU PHWR technology, which was originally developed for the MZFR reactor in the Federal Republic of Germany, as well as their know-how in pressurized (light-) water reactors (PWRs) design and construction. The CNEA also has agreements with Atomic Energy of Canada Ltd. for the transfer of technology related to CANDU-type PTHWRs. The CNEA and ENACE have acquired considerable practical experience from the construction and operation of the 367 MWe Atucha I PHWR and the 648 MWe Embalse PTHWR; ENACE is currently building Argentina's third nuclear power plant, Atucha II, a 745 MWe PHWR. (author)
The nuclear fuel elements of the RA-3 reactor consist in 19 rectangular fuel plates held in position by two lateral structural plates. The whole assembly is coupled to the lower nozzles that fits in the reactor core grid. The inner plates are 1.5 mm thick, 70.5 mm wide and 655 mm long and the outer plates are 100 mm longer. The fuel plates are formed by a core of an AI-U alloy co-laminated between two plates of Al. Enrichment is 90% 235U. After being extracted from the reactor, the fuel elements have been let to cool down in the reactor storage pool and finally moved to the storage facility. This facility is a grid of vertical underground channels connected by a piping system. The system is filled with processed and controlled water. At the present the storage capacity of the facility is near to be depleted and some indications of deterioration of the fuel elements has been detected. Due to the present status of the facility and the spent fuel stored there, a decision has been taken to proceed to modify the present underwater storage to dry storage. The project consist in: a) Decontamination and conditioning of the storage channels to prepare them for dry storage. b) Disassembly of the fuel elements in hot cells in order to can only the active fuel plates in an adequate tight canister. c) The remnant structural pieces will be treated as low level waste. (author). 10 figs
This is the final work to obtain a Diploma on Specialization in Application of Nuclear Technological Energy, carried out at the Research Reactor RA-6, from March to December 1999. Different work has been realized on the Tangential Tube N of the 500 KW Argentine RA-6 research reactor, in order to add a new technique to the present existing analytical methods. This Prompt Gamma Neutron Activation Analysis technique (PGNAA) requires a beam of collimated thermal neutrons, a lowest possible gamma radiation, and a thermal component of the biggest possible cadmium rate. It also must have a high resolution detection system for the measurement of the gamma radiation emitted after the capture of the neutron produced in the study sample. Continuing with the facility's technical requirements, a collimator was installed inside the N passing tube, in order to concentrate the neutrons coming from the nuclear core and also to compensate possible losses during the path. This collimator is 440mm long and 200 mm in diameter and consists of lead and steel cylinders with different size holes on the inside, so that it can deliver a 50 mm diameter beam of thermal collimated neutrons. Two 100 mm thick bismuth filters are inside the passing tube, to reduce the gamma component inside de beam, coming from the reactor core. This work aims to the characterization of the thermal and epithermal component of the neutron beam in the collimator and at the exit of it , and also to prove experimentally that the collimator achieves the technical specifications for which it was designed and built, specifically by verifying its functioning (degree of convergence of the beam obtained). On the other hand, it is necessary to learn about the PGNAA technique in order to define the technical requirements for its adequate operation. (author)
Two pressurized heavy water reactors are being operated in Argentina: Atucha 1, a Siemens KWU designed and built pressure vessel 345 MWe reactor, started in 1974, and Embalse, a CANDU-600 MWe, started in 1983. Post-irradiation tests have been performed in accordance with the needs of fuel development and control programs for internal parts, such as the coolant channels (CC) where the fuel elements (FE) dwelled. The bays built in both NPP offer a good place to perform a large variety of pool-side inspection and testing activities. During the last 20 years more than 2000 CANDU-type FE, more than 1000 Atucha FE and above 100 Atucha CC, have been inspected in these bays. The usual inspection activities consist of: visual inspection, sipping tests, disassembling of FE, metrology, gamma scanning and eddy current testing. In this paper all of these techniques are briefly described and the obtained experience is shown. (author)
In Argentina, the construction, operation, and use of research and radioisotope production reactors is and has been an important method of personnel preparation for the nuclear power program. Moreover, it is a very suitable means for technology transfer to countries developing their own nuclear programs. At present, the following research reactors are in operation in Argentina: Argentine Reactor 0 (RA-0); Argentine Reactor 1 (RA-1); Argentine Reactor 2 (RA-2); Argentine Reactor 3 (RA-3); Argentine Reactor 4 (RA-4). The Argentine Reactor 6 (RA-6), under construction, should reach criticality in 1981
In order to anticipate the possibilities of future nuclear technology exports, the technological capacities of the organizations and companies that make up the Argentine nuclear sector are analyzed together with the evolution of their possible markets. The main export opportunities are seen in the field of the research reactors, nuclear fuel elements, heavy water and radioisotopes for medical and industrial applications
The Argentine Radiation Protection Society (SAR) is a non profit society, member of IRPA. It was originally launched in 1987 and a formal constitution was adopted in 1983. Presently, SAR has 220 active members, professionals and technicians dedicated to a variety of disciplines related to different radiation protection aspects: medicine, industry, research and teaching. The basic SAR objectives are: to promote research and knowledge exchange on radiation protection topics and related disciplines; to promote the comprehension of radiation protection criteria with regard to existence and handling of radioactive and fissile materials and any other radiation sources; to foster the conception of radiation protection as a professional discipline and to contribute to its permanent improvement; to promote the diffusion of the information related to all radiation protection and nuclear safety aspects, and radiation protection standards and recommendations, not only within the scientific, technical and academic areas, but also to general public
Standards of mandatory application, established by Law No. 22729 of February, 1983, on radiopharmaceuticals and radiosterilization of products for medical use, issued as a supplement to the text of the Argentine National Pharmacopoeia. In particular, the general characteristics, identification and purity tests, radioactivity valuation, top date of utilization, and form of conservation of different radiopharmaceuticals are described. (C.A.K.)
The paper describes Argentina's nuclear program, detailing its objectives, the schedule of construction of nuclear plants and local production of required equipment. The technologies adopted so far, the local industrial and engineering participation, the preliminary study for the construction of the next power station and Argentina's nonproliferation nuclear policy are analyzed. Argentina's point of view on Canadian nonproliferation policy and CANDU reactor export is discussed
This text intends to reflect a coherent and sustained management in the Argentine nucleoelectrical policy. Through individual thematic unities connected between them, the basic structure consists of three principal parts. The first part introduces a broad panorama of atomic energy in the world, in the international treaties and organizations. Also the technical, economic and political aspects which had influence in the Argentine nuclear policies, particularly in the electrical production with nuclear power plants, are considered in this part. The second part describes the historical sequence of the principal achievements of the Argentine National Atomic Energy Commission (CNEA) in the nuclear industry. A mention of particular criteria adopted in each situation and the intention and motivations that guide the decisions are also considered. Finally, an actual balance of the nucleoelectrical technology situation in Argentine and in the world is presented. (Author)
Compilation of 59 papers of different authors, most of whom are personnel from the Argentine National Atomic Energy Commission (CNEA), the others belonging to the firms involved in the development of the Argentine Nuclear Programme. The papers are arranged in 7 sections comprising the following groups of subjects; experimental and power reactors; fuel elements' fabrication study; prospection, extraction, production and study of nuclear materials; radiological and nuclear safety; instrumentation and control; quality assurance, and technological applications. (R.J.S.)
Argentine Nuclear Development started in early fifties. In 1957, it was decided to built the first a research reactor. RA-1 reactor (120 kw, today licensed to work at 40 kW) started operation in January 1958. Originally RA-1 was an Argonaut (American design) reactor. In early sixties, the RA-1 core was changed. Fuel rods (20% enrichment) was introduced instead the old Argonaut core design. For that reason, a critical facility named RA-0 was built. After that, the RA-3 project started, to build a multipurpose 5 MW nuclear reactor MTR pool type, to produce radioisotopes and research. For that reason and to define the characteristics of the RA-3 core, another critical facility was built, RA-2. Initially RA-3 was a 90 % enriched fuel reactor, and started operation in 1967. When Atucha I NPP project started, a German design Power Reactor, a small homogeneous reactor was donated by the German Government to Argentina (1969). This was RA-4 reactor (20% enrichment, 1W). In 1982, RA-6 pool reactor achieved criticality. This is a 500 kW reactor with 90% enriched MTR fuel elements. In 1990, RA-3 started to operate fueled by 20% enriched fuel. In 1997, the RA-8 (multipurpose critical facility located at Pilcaniyeu) started to operate. RA-3 reactor is the most important CNEA reactor for Argentine Research Reactors development. It is the first in a succession of Argentine MTR reactors built by CNEA (and INVAP SE ) in Argentina and other countries: RA-6 (500 kW, Bariloche-Argentina), RP-10 (10MW, Peru), NUR (500 kW, Algeria), MPR (22 MW, Egypt). The experience of Argentinian industry permits to compete with foreign developed countries as supplier of research reactors. Today, CNEA has six research reactors whose activities have a range from education and promotion of nuclear activity, to radioisotope production. For more than forty years, Argentine Research Reactors are working. The experience of Argentine is important, and argentine firms are able to compete in the design and
Vogel, Valerie; Pedersen, Jes Søe; Giraud, Tatiana;
the native range) and secondary introductions (from sites with established invasive supercolonies) were important in the global expansion of the Argentine ant. In combination with the similar social organization of colonies in the native and introduced range, this indicates that invasiveness did not...
The Argentine nuclear programme, as it stands at present, provides for the construction of four nuclear power plants in addition to those of Atucha I and Embalse and for the establishment of such fuel cycle facilities as are required to supply all of these plants. This paper evaluates the radiological impact (collective dose commitment) expected from the management of the radioactive wastes arising in the facilities mentioned above throughout the useful life of the reactors. The maximum individual doses to be expected as a result of the planned high-level-waste repository are also estimated. The evaluations presented are partly specific to the sites under consideration, but they also include estimates of the total collective dose commitments resulting from the management of radioactive waste under the Argentine nuclear programme. (author)
Muzzini, Elisa; Eraso Puig, Beatriz; Anapolsky, Sebastian; Lonnberg, Tara; Mora, Viviana
OVERVIEW. FULL BOOK EXPECTED IN JUNE 2016. Argentina’s path to economic prosperity is through efficient, sustainable and economically thriving cities. Not only are cities a spatial concentration of people, but also they generate agglomeration economies by concentrating ideas, talent, and knowledge. Argentina is one of the most urbanized countries in Latin America, with 90 percent of Argentine people currently living in cities. Argentina’s cities are geographically and economically diverse, an...
The purpose of this work is to introduce the present-day situation of the Libraries of Science in the Argentine Republic, emphasising on there possibilities of access to information. The first division that we can do in this area is: special libraries and academic libraries. This is our starting point. We also point out the Programs or Projects originated in the Ministry of Culture and Education that directly affect the present situation of academic libraries, like the University Interc...
The International Organization for Standardization (ISO) has more than 200 Technical Committees that develop technical standards. During April 2004 took place in Buenos Aires the 14th Plenary of the ISO/TC 85 Nuclear Energy Committee. During this Plenary issues as Nuclear Terminology, Radiation Protection, Nuclear Fuels, Nuclear Reactors and Irradiation Dosimetry was dealt with. 105 International delegates and 45 National delegates (belonging to CNEA, ARN, NASA, INVAP, CONUAR, IONICS and other organizations) attended the meetings. During this meeting ISO/TC 85 changed its scope; the new scope of the Committee is 'Standardization in the fields of peaceful applications of nuclear energy and of the protection of individuals against all sources of ionizing radiations'. This work summarizes the most important advances and resolutions about the development of standards taken during this meeting as well as the main conclusions. (author)
The Argentine development in the nuclear field is analyzed from an anthropological and sociological standpoint. The author has made his 'field work' at the Reactor and Power Plants sector of the National Atomic Energy Commission. She examines the perception that the scientists and other workers of the nuclear field have of the role of its discipline and consequently of its own role in the society. The analysis is carried out into the framework of the situation of nuclear energy in the world and in Argentina in particular
Ninth Argentine congress on biology and nuclear medicine; fourth Southernmost sessions of ALASBIMN (Latin-American Association of Biology and Nuclear Medicine); first Spanish-Argentine congress on nuclear medicine; first Argentine sessions on nuclear cardiology
This work deals with all the papers presented at the 9. Argentine congress on biology and nuclear medicine; IV Southernmost sessions of ALASBIMN; I Spanish-Argentine congress on nuclear medicine and I Sessions Argentine sessions on nuclear cardiology held in Buenos Aires, Argentina, from October 14 - 18, 1991
As part of phase I/II melanoma BNCT clinical trial conducted in Argentina in a cooperative effort of the Argentine Atomic Energy Commission (CNEA) and the Oncology Institute Angel H. Roffo (IOAHR), 7 patients (6 female-1 male) received eight treatment sessions covering ten anatomical areas located in extremities. Mean age of the patients was 64 years (51-74). The treatments were performed between October 2003 and June 2007. All patients presented multiple subcutaneous skin metastases of melanoma and received an infusion containing ∼14 gr/m2 of 10borophenyl-alanine (BPA) followed by the exposition of the area to a mixed thermal-epithermal neutron beam at the RA-6 reactor. The maximum prescribed dose to normal skin ranged from 16.5 to 24 Gy-Eq and normal tissue administered dose varied from 15.8 to 27.5 Gy-Eq. Considering evaluable nodules, 69.3% of overall response and 30.7% of no changes were seen. The toxicity was acceptable, with 3 out of 10 evaluable areas showing ulceration (30% toxicity grade 3).
The different applications of radioisotopes: as sealed sources or tracers, as well as activation analysis have cast a new light on Argentine engineering and industry. The Argentine Atomic Energy Commission is carrying out an active plan for the developement and promotion of these techniques since the 60's. This report describes and analyzes the most outstanding applications, and brings up to date other previous papers on the same subject. It suggests some ideas for achieving a complete penetration of radioisotope techniques into Argentine technology. It also outlines some future perspectives, based on present statistical data. (author)
The document reproduces the texts of the speeches made by the Presidents of Argentina and Brazil at Foz do Iguacu, Brazil, on 28 November 1990, at the signing of the Argentine-Brazilian Declaration on Common Nuclear Policy
Carrizo, Silvina Cecilia
Les réseaux d'hydrocarbures en Argentine ont vécu une restructuration brutale, lors de la réforme de l'Etat des années 1990. La dérégulation des activités et les privatisations des entreprises YPF et Gas del Estado ont induit la re-concentration du secteur, désormais sous l'empire des entreprises étrangères, dont Repsol YPF est le leader. La fédéralisation des ressources au bénéfice des provinces contribue à l'affaiblissent et à la décapitalisation de l'Etat. Ces changements ont entraîné une ...
The Scientific and Technical Support Department of the Argentine National Board of Nuclear Regulation (ENREN) has developed a Remote Monitoring and Surveillance System (RMSS) that provides a media to verify state of variables related to the monitoring and surveillance activities of nuclear facilities, mainly safeguard applications. RMSS includes a variety of on site installed sensors, an authenticated radiofrequency communication link, a receiver processing unit, an active vision set and a user friendly personal computer interface to collect, view and store pertinent histories of events. A real time data base allows consulting, maintenance, updating and checking activities. RMSS could be integrated into a LAN or WAN via modem for use in a remote operation scheme. In this paper a description of the RMSS is provided. Also, an overview of the RMSS operation at one facility under safeguards belonging to the National Commission of Atomic Energy (CNEA) is presented. Results and conclusions of the system associated with this facility are given. (author). 37 figs
INVAP, an Argentine company founded more than three decades ago, is today recognized as one of the leaders within the research reactor industry. INVAP has participated in several projects covering a wide range of facilities, designed in accordance with the requirements of our different clients. For complying with these requirements, INVAP developed special skills and capabilities to deal with different fuel assemblies, different core cooling systems, and different reactor layouts. This paper summarizes the general features and utilization of several INVAP research reactor designs, from subcritical and critical assemblies to high-power reactors IAEA safety
Suckling, D M; Peck, R W; Manning, L M; Stringer, L D; Cappadonna, J; El-Sayed, A M
Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m(2)) to 1- and 4-m(2) plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. PMID:19034574
The technological and economic advantages of radiation as a means of sterilization have led to a steady expansion of its use. With the significant increase in the radiosterilization of medical products, the health authorities have established standards for the use of radiation for that purpose. These standards will be incorporated in the next edition of the Argentine Pharmacopoeia. In general, Argentine legislation in this area is based on the IAEA's Code of Practice for Radiosterilization of Medical Products. The microbiology services of Argentina's National Atomic Energy Commission (CNEA) determine the number of viable microorganisms in each product and package the product before irradiation. The controls are carried out on random samples. At the same time, the chemistry laboratories carry out quality controls on new products which have received sterilizing doses of gamma radiation. The gas sterilization methods employed most widely in the industrial manufacture of thermolabile products involve the use of ethylene oxide or formaldehyde. The cost of this process is influenced considerably by the fact that Argentina has to import ethylene oxide. The low penetrating power of formaldehyde means that the package containing the product must still be open at the time of sterilization if an adequate safety margin is to be ensured; consequently, one needs sterile installations for the post-irradiation sealing of packages. The capital and operating coats of such installations are high. A comparison has been made of the costs of sterilizing 11000 m3 of a product with a density of 0.1 g/cm3 and the following relative values obtained: ethylene oxide, 399.2; formaldehyde, 947.5; gamma radiation, 166.0. Studies of the effects of sterilizing doses on certain pharmaceutical products have demonstrated that the radiosterilization of some drugs is possible. The CNEA has designed an installation for the radiosterilization of medical products; the installation would have a 500000-Ci
Into de framework of the program of research reactors and nuclear power plants, the operating Argentine reactors are described. The uses of the research reactors in Argentina are summarized. The reactors installed by Argentina in other countries (Peru, Algeria, Egypt) are briefly described. The CAREM project for the design and construction of an innovator small power reactor (27 MWe) is also described in some detail. The next biennial research and development program for reactor is briefly outlined
Rowles, Alexei D; Silverman, Jules
The ability of species to invade new habitats is often limited by various biotic and physical factors or interactions between the two. Invasive ants, frequently associated with human activities, flourish in disturbed urban and agricultural environments. However, their ability to invade and establish in natural habitats is more variable. This is particularly so for the invasive Argentine ant (Linepithema humile). While biotic resistance and low soil moisture limits their invasion of natural habitats in some instances, the effect of food availability has been poorly explored. We conducted field experiments to determine if resource availability limits the spread and persistence of Argentine ants in remnant natural forest in North Carolina. Replicated transects paired with and without sucrose solution feeding stations were run from invaded urban edges into forest remnants and compared over time using baits and direct counts at feeding stations. Repeated under different timing regimes in 2006 and 2007, access to sucrose increased local Argentine ant abundances (1.6-2.5 fold) and facilitated their progression into the forest up to 73 +/- 21% of 50-m transects. Resource removal caused an expected decrease in Argentine ant densities in 2006, in conjunction with their retreat to the urban/forest boundary. However, in 2007, Argentine ant numbers unexpectedly continued to increase in the absence of sugar stations, possibly through access to alternative resources or conditions not available the previous year such as honeydew-excreting Hemiptera. Our results showed that supplementing carbohydrate supply facilitates invasion of natural habitat by Argentine ants. This is particularly evident where Argentine ants continued to thrive following sugar station removal. PMID:19452171
Ferradas, Claudia Mónica
This study proposes a definition of Anglo-Argentine literature, a literary corpus that has not been explicitly defined, and provides a reading list of Anglo-Argentine works on the basis of that definition. The research is based on the presupposition that Anglo-Argentine texts can be used to contribute to an intercultural approach to language and literature teaching in the Argentine higher education context. Such texts can encourage reflection on how writing on Argentina in English has co...
Buczkowski, Grzegorz; Bennett, Gary W
The Argentine ant (Linepithema humile) is an invasive species that disrupts the balance of natural ecosystems by displacing indigenous ant species throughout its introduced range. Previous studies that examined the mechanisms by which Argentine ants attain ecological dominance showed that superior interference and exploitation competition are key to the successful displacement of native ant species. The objective of this research was to test the hypothesis that effective interference competition by Argentine ants may also be detrimental to the survival of Argentine ant colonies where Argentine ants and native ants compete at toxic baits used to slow the spread of Argentine ants. To study this hypothesis, we examined the competitive interactions between Argentine ants and native odorous house ants, Tapinoma sessile, in the presence and absence of toxic baits. Results showed that Argentine ants aggressively outcompete T. sessile from toxic baits through efficient interference competition and monopolize bait resources. This has severe negative consequences for the survival of Argentine ants as colonies succumb to the toxic effects of the bait. In turn, T. sessile avoid areas occupied by Argentine ants, give up baits, and consequently suffer minimal mortality. Our results provide experimental evidence that highly efficient interference competition may have negative consequences for Argentine ants in areas where toxic baits are used and may provide a basis for designing innovative management programs for Argentine ants. Such programs would have the double benefit of selectively eliminating the invasive species while simultaneously protecting native ants from the toxic effects of baits. PMID:18559180
In 1985, both the Algerian Commissariat of New Energies and the Argentine National Atomic Energy Commission plus the firm INVAP S.E., started a series of mutual visits aimed at defining the mechanisms for cooperation in the nuclear field. Within this framework, a commercial contract was undersigned covering the supply of a low-power reactor (RUN), designed for basic and applied research in the fields of reactor physics and nuclear engineering. The reactor may also be used for performing experiences with neutron beams, for the irradiation of several materials and for the training of technicians, scientists and operators
Advanced fuel cycles, nuclear power reactors, are studied all over the world nowadays, mainly as a way of enhancing the use of nuclear fuel. Such goal is usually decomposed under tree main aspects: environmental, economical and strategic. The Tandem Cycle has demonstrated, under these aspects, to be one of the most promising options among the advanced cycles. This cycle deals, basically, with the reutilization of irradiated ('burned') fuel in PWR type reactors, in CANDU type reactors, as this fuel also contains about 1.5% of fissile material. Brazilian and Argentine nucleoelectric generation options are, coincidentally, in accordance with this option of advanced cycle. This work thus deals with the viability analysis, both technical and economic, of the implementation of a Tandem cycle between the brazilian reactor of Angra-I (PWR) and the argentine reactor of Embalse (CANDU). Tree options of Tandem Cycle have been analysed specifically for the reactors in question. For this analysis, a methodology was developed and a computer program was designed to analyse the technical and economical parts of these options. Besides, countless details have been considered, such as: the influence of actinide elements, test and adjustment of the nuclear data library utilized in the calculations, observation of the safety and control of the CANDU reactor operating on the Tandem Cycle, etc. Given the analyses done, the adoption of the Tandem Cycle-2, in which the fuel irradiated from the PWR is diluted in depleted uranium, was suggested for an occasional implementation of this option of advanced fuel cycle between the reactors of Angra-I and Embalse as a general conclusion of this work. (author)
Full Text Available Objectives: This study aimed to investigate the knowledge and attitudes of Argentine women 65 years of age and older regarding urinary incontinence (UI. Methods: A cross-sectional study of 238 community-dwelling Argentine women 65 years of age and older was conducted in San Justo, Argentina. Data were collected by in-person interviews. Results: Regarding knowledge, 232 (97.5% of the women surveyed were familiar with the term urinary incontinence, but 152 (63.9% falsely believed that UI is a normal part of aging and 163 (68.5% did not know about pelvic exercises or a surgical option to treat UI. A total of 106 (44.5% women reported symptoms of UI. Discussion: Older Argentine women are misinformed about UI. Interventions are necessary to increase their knowledge and healthcare seeking behaviors.
Full text: In 1997 began in Argentine, sponsored by Nuclear Regulatory Authority (ARN) the intercomparison program for personal dosimetry laboratories, on a voluntary basis. Up to know 6 exercises have been done. The program began with a workshop to present the quantities, personal dose equivalent, Hp(10) and extremities dose equivalent, Hs(d). The first aim of this program was to know the true sate of personal dosimetry laboratories in the country, and then introduce the personal dose equivalent, Hp(10) into the dose measurements. The Regional Reference Center for Dosimetry (CCR), belonging to CNEA and the Physical Dosimetry Laboratory of ARN performed the irradiation. Those were done air free and on ICRU phantom, using x-ray, quality ISO: W60, W110 and W200; and 137Cs and 60Co gamma rays. The irradiation was made following ISO 4037 (2) recommendations. There are studied the dose, energy and angular response of the different measuring system. The range of the dose analyzed was from 0.2 mSv up to 80 mSv. The beam incidence was normal and also 20o and 60o. The dosimeters irradiation's were performed kerma in free in air and in phantom in order to study the availability of the service to evaluate the behavior as a function of kerma free in air or Hp(10). At the same time several items have been asked to each participant referring to the action range, the detectors characteristics, the laboratory procedures, the existence of an algorithm and its use for the dosimeter evaluation and the wish to participate in a quality assurance program. The program worked in writing a standard of personal dosimetry laboratories, that was published in 2001. In this work the results of each laboratory and its performance based on the ICRP-60 and ICRP-35 acceptance criteria are shown. Also the laboratory evolution and inquiry analyses have been included. (author)
The status of power reactors and nuclear activity in Argentina for the period 1988-1990 are described. The reactor shutdown at the Central Nuclear Atucha I and repair works are discussed. Joint venture of the Comision Nacional de Energia Atomica and KWU developments are reported, including the conceptual design of an additional heat sink for pressurized water reactors, a feasibility analysis of the Co-60 production in pressure vessel PHWRs and a study of severe postulated accidents for pressure vessel PHWR. 11 refs, 4 figs
The Argentine government is using output-based contracts with the private sector for rehabilitation and maintenance of its nonconcessioned road network. The multiyear lump sum contracts, funded by the government, specify required road service outputs and use incentive-based payment schedules to ensure the quality of the work. After three years of operation the 60 contracts (averaging US$10...
@@ The Sino-Argentine satellite laser ranging (SLR) system ranks second in the pass total of satellites it has observed among the SLR satellite observatories worldwide, according to statistics of the International Laser Ranging Service from October 2007 to September 2008. In addition, it tops the world in observing high orbit satellites, a difficult task to perform.
The paper describes the present situation in the Argentine Republic relating to the treatment of radioactive wastes, the methodology used for siting a radioactive waste repository and the legal problems associated with the provincial jurisdiction on the chosen territory. It also describes related financing and nuclear liability problems (NEA)
To analyze the legal aspects of the cooperation agreement between Australia and Argentina signed in Camberra on August 8, 2001, the authors elaborate upon the following points: 1. The interpretation of the constitutional texts. Its need; 2. Facts: the development of nuclear energy in Argentina. The contract INVAP-ANSTO. The cooperation agreement Argentina-Australia; 3. The great publicity campaign. The appeal to fear; 4. The difference with the case of power reactors. Distinction between power and research reactors; 5. The difference with the Chernobyl case; 6. Shipment safety; 7. Other clarifications; 8. Factual and juridical distinction between spent fuel and radioactive waste concepts; 9. The regulatory framework of the difference; 10. The essence of the adjective 'Immediate'. Its juridical meaning; 11. The concept of 'entry'. The need to overcome an intentional literalness; 12. The harmonious interpretation of the constitution; 13. The engagement with the future generations; 14. The adaptation to the global trends. The Kyoto protocol; 15. The bases of the constitutional doctrine. They conclude that nothing in the agreement is contrary to the Argentine constitution
Purpose: To provide a spray cooling structure wherein the steam phase in a bwr reactor vessel can sufficiently be cooled and the upper cap and flanges in the vessel can be cooled rapidly which kept from direct contaction with cold water. Constitution: An apertured shielding is provided in parallel spaced apart from the inner wall surface at the upper portion of a reactor vessel equipped with a spray nozzle, and the lower end of the shielding and the inner wall of the vessel are closed to each other so as to store the cooling water. Upon spray cooling, cooling water jetting out from the nozzle cools the vapor phase in the vessel and then hits against the shielding. Then the cooling water mostly falls as it is, while partially enters through the apertures to the back of the shielding plate, abuts against stoppers and falls down. The stoppers are formed in an inverted L shape so that the spray water may not in direct contaction with the inner wall of the vessel. (Horiuchi, T.)
Sebastián Senesi; Fabio Ribas Chaddad; Hernán Palau
Argentina is among the four largest producers of soybeans, sunflower, corn, and wheat, among other agricultural products. Institutional and policy changes during the 1990s fostered the development of Argentine agriculture and the introduction of innovative process and product technologies (no-till, agrochemicals, GMO, GPS) and new investments in modern, large-scale sunflower and soybean processing plants. In addition to technological changes, a "quiet revolution" occurred in the way agricultu...
Cooper, Monica L; Daane, Kent M.; Nelson, Erik H; Varela, Lucia G; Battany, Mark; Tsutsui, Neil D.; Rust, M K
Liquid ant baits are an alternative to broad-spectrum insecticide sprays conventionally used to control Argentine ants. We review the development of liquid ant baits, which capitalize on the ants’ sugar-feeding requirements and social structure to deliver small doses of toxicant throughout the colony. The ant bait program described here, developed for commercial vineyards, also has the potential to facilitate the use of biological controls for mealybug and scale pests. The implementation of a...
Other-initiated repair is an essential interactional practice to secure mutual understanding in everyday interaction. This article presents evidence from a large conversational corpus of a sign language, showing that signers of Argentine Sign Language (Lengua de Señas Argentina or ‘LSA’), like users of spoken languages, use a systematic set of linguistic formats and practices to indicate troubles of signing, seeing and understanding. The general aim of this article is to provide a...
Within the framework of the RERTR Program and supported by the technical cooperation work agreed upon between the USA and Argentina in May 1979, the CNEA Nuclear Fuel Department - Low Enriched Fuel Elements Project (ECBE Project) has carried on its own program for developing fuels with low enrichment for research and test reactors. Up to the present, its main objective has been to replace the highly enriched fuel used in its only reactor (RA-3) for research, development and radioisotopes production. The basic stages of the Argentine Program are shown. The densities reached were within the range of 3.12 to 3.58 g/cm3 for U3O8-Al, 2.99 to 3.09 g/cm3 for UAl2-Al and 5.18 to 6.10 g/cm3 for U3Si-Al. If further miniplates can be irradiated, it is the purpose of the program to research uranium densities of 3.5 g/cm3 in UAl2-Al and 6.5 g/cm3 in U3Si-Al
Weijer, W.; Vevier, F.; Gille, S.T.; Dijkstra, H.A.
In this paper the spectrum of barotropic basin modes of the Argentine Basin is shown to be connected to the classical Rossby basin modes of a flat-bottom (constant depth), rectangular basin. First, the spectrum of basin modes is calculated for the Argentine Basin, by performing a normal-mode analysi
The 38th Annual meeting of the Argentine Association of Nuclear Technology was organized by the AATN (Asociacion Argentina de Tecnologia Nuclear) in Buenos Aires, Argentine, between the 14 and 18 November of 2011. In this event 146 papers in 16 Sessions, with 13 Plenary Conferences and 3 Roundtables were presented.
C.D. Golijow; G. Giovambattista; M.V. Rípoli; F.N. Dulout; M.M. Lojo
Many cattle breeds have been subjected to high selection pressure for production traits. Consequently, population genetic structure and allelic distribution could differ in breeds under high selection pressure compared to unselected breeds. Analysis of k-casein, aS1-casein and prolactin gene frequencies was made for Argentine Creole (AC) and Argentine Holstein (AH) cattle herds. The calculated FST values measured the degree of genetic differentiation of subpopulations, depending on the varian...
Within the environmental applications of ionizing radiation, disinfection of wastewaters or sewage sludges is one of the most best known. Argentina based the project of a full scale irradiation plant on the gamma irradiation application, utilizing Argentine made Cobalt-60 sources. The design characteristics, process descriptions and costs are included. The research project developed information about the irradiation effects on the sludges with respect to plant performance. For the purpose of oxi-irradiation experiments, a lab-scale pool irradiator was constructed and is described. (author)
This paper presents a review of the activities performed by the Reactors Chemistry Department of the Argentine National Atomic Energy Commission during 1989-1990. This department provides scientific-technical services and assistance in all chemical problems related to design, construction, commissioning and decommissioning of nuclear power plants
The Argentine RA-3 reactor is described as a model facility for the information to be provided to the IAEA in accordance with the requirements of the Model Additional Protocol. RA-3 reactor was designed as a 5 MW swimming pool reactor, moderated and cooled with light water. Its fuel was 90% enriched uranium. The reactor started its operation in 1967, has been modified and improved in many components, including the core, that now is fueled with moderately enriched uranium
Suckling, David Maxwell; Peck, Robert W; Stringer, Lloyd D; Snook, Kirsten; Banko, Paul C
Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2–3 m s−1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. PMID:20077128
Since its creation in 1967, the Argentine Radiation Protection Society (SAR) promotes all the radiation protection and nuclear safety aspects not only within the scientific, technical and academic areas, but also to general public. To fulfill this objective, SAR organised training and refresher courses, seminars and workshops on RP subjects. During 2002, SAR organised 7 basic and specialized courses regarding the uses of radioactive materials in industrial applications and the course on medical response in radiological accidents, that was attended by Argentine and other Latin American participants. The programmes of the courses are developed in compliance with the legal requirements and also considering specifics needs. In this paper, the characteristics of the courses are enunciated and basic statistics regarding courses and participants are presented. For the 2003 and 2004, SAR foresees the organisation of 18 courses per year and has the capacity to deliver other courses by request. all the courses are delivered in Spanish language. Based on this educational experience SAR consider a priority the inclusion, of a RP module in all the scientific graduate programmes to generate awareness on the importance of RP. Taking into account the migration of professionals to Europe and North America and the Globalization, SAR advocates the harmonization of RP syllabus to attain an international recognition. (Author)
The paper describes studies carried out for siting a repository for high level radioactive wastes originating in the nuclear programme of Argentina. A summary is given of the basic criteria governing the study, as well as a description of the activities involved in the selection of the site, its validation and the derivation of the design basis of the repository, together with conceptual definitions regarding its engineering. At the end of the 1970s the Argentine authorities decided to explore alternatives for disposing of the high level radioactive wastes that would eventually be generated by the country's nuclear programme. This programme involves nuclear power reactors that will generate a time integrated electric energy of about 100 GW·a by the end of the century. The programme also includes the reprocessing of the spent fuel. On the basis of the criteria adopted for the disposal of high level wastes, a site in stable, unfractured granite, near Gastre in the Province of Chubut, was selected for detailed studies out of about 200 potential sites. This site has been thoroughly investigated and its suitability will be validated. Work has also progressed on the design of the repository. (author)
The bases and scope of the projects for heavy water production that are being currently developed by the Argentine National Atomic Energy Commission (CNEA) are described. As an introduction, the following points are presented: a) the fundamentals of heavy water utilization in a nuclear reactor, with a mention of its properties and uses, b) a review of the physicochemical bases of the principal methods for heavy water production: chemical exchange (monothermal and bithermal processes), distillation and electrolysis, with tables summarizing the fundamental characteristics of the first two ones, and an evaluation of the different production methods from the viewpoint of their application in an industrial scale; and c) a synthetic information, in the form of tables, about the world's heavy water production. The subject of heavy water production in Argentina is treated in the principal section, describing the scope, location, main characteristics and chemical processes corresponding to the projects being developed by CNEA, which currently are the installation of an Industrial Plant in Arroyito (Province of Neuquen), purchased on a turnkey basis and using the NH3/H2 isotopic exchange method; the installation of an Experimental Plant in Atucha (Province of Buenos Aires), for the development of the domestic technology of heavy-water production by the SH2/H2O isotopic exchange method, and the development of the engineering of an industrial plant (''Module 80''), based on the Experimental Plant's technology. (M.E.L.)
The first part of the book makes a short description of the nuclear development in the 20th. Century in the international, Latin American and Argentine frameworks. The second part outlines the relationship between the nuclear technology and the international relations in the light of the different theoretical models of international relations. Finally the third part analyzes in the international context the Argentine nuclear policy, from the presidency of J. D. Peron that of C. Menem. The international restraints to the Argentine nuclear policy are also described
Nowhere in Latin America has the privatization process been more aggressively pursued than in Argentina where President Carlos Menem has successfully turned over the bulk of state companies to the private sector. In the energy sector, that meant the divestiture in 1992 of Gas del Estado, the state-owned integrated gas transportation and distribution company. It was split in two transportation companies: Transportadora de Gas del Sur (TGS) and Transportadora de Gas del Norte (TGN), and eight distribution companies. TGS is the largest transporter of natural gas in Argentina, delivering more than 60 percent of that nation's total gas consumption with a capacity of 1.9 Bcf/d. This is the second in a series of Pipeline and Gas Journal special reports that discuss the evolving strategies of the natural gas industry as it continues to restructure amid deregulation. The article focuses on TGS, the Argentine pipeline system in which Enron Corp. is a key participant
We have used Moessbauer spectroscopy to investigate iron-bearing mineral samples of loess and paleosols from a geologic section at La Plata, Argentina, 34 deg. 54' 14'' S and 58 deg. 2' W. Hematite is by far the dominant iron-bearing magnetic component in initial loess and paleosol samples. The samples were also subjected to magnetic separation. The magnetically enriched loess fractions show a remarkable increase in the content of magnetite. The enhancement of non-magnetic Fe3+ and a decrease of Fe2+ mineral phases in the paleosol layer seem to be a consequence of the process of pedogenesis which also caused a dissolution of magnetic iron oxides by weathering. The increase of magnetite in the silt fraction suggests that the wind could have been the main carrier of magnetic minerals, causing the major differences in the magnetic parameters between loess and paleosols in the Argentine loess plateau
Pedersen, Jes Søe; Krieger, Michael J. B.; Vogel, Valérie;
Kinship among group members has long been recognized as a main factor promoting the evolution of sociality and reproductive altruism, yet some ants have an extraordinary social organization, called unicoloniality, whereby individuals mix freely among physically separated nests. This type of social...... organization is not only a key attribute responsible for the ecological dominance of these ants, but also an evolutionary paradox because relatedness between nestmates is effectively zero. Recently, it has been proposed that, in the Argentine ant, unicoloniality is a derived trait that evolved after its...... introduction into new habitats. Here we test this basic assumption by conducting a detailed genetic analysis of four native and six introduced populations with five to 15 microsatellite loci and one mitochondrial gene. In contrast to the assumption that native populations consist of family-based colonies with...
Autin, Julia; Scheck-Wenderoth, Magdalena; Loegering, Markus; Anka, Zahie; Vallejo, Eduardo; Rodriguez, Jorge; Marchal, Denis; Reichert, Christian; di Primio, Rolando
The Argentine margin presents a strong segmentation with considerable strike-slip movements along the fracture zones. We focus on the volcanic segment (between the Salado and Colorado transfer zones), which is characterized by seaward dipping reflectors (SDR) all along the ocean-continent transition [e.g. Franke et al., 2006; Gladczenko et al., 1997; Hinz et al., 1999]. The segment is structured by E-W trending basins, which differs from the South African margin basins and cannot be explained by classical models of rifting. Thus the study of the relationship between the basins and the Argentine margin itself will allow the understanding of their contemporary development. Moreover the comparison of the conjugate margins suggests a particular evolution of rifting and break-up. We firstly focus on the Colorado Basin, which is thought to be the conjugate of the well studied Orange Basin [Hirsch et al., 2009] at the South African margin [e.g. Franke et al., 2006]. This work presents results of a combined approach using seismic interpretation and structural, isostatic and thermal modelling highlighting the structure of the crust. The seismic interpretation shows two rift-related discordances: one intra syn-rift and the break-up unconformity. The overlying sediments of the sag phase are less deformed (no sedimentary wedges) and accumulated before the generation of oceanic crust. The axis of the Colorado Basin trends E-W in the western part, where the deepest pre-rift series are preserved. In contrast, the basin axis turns to a NW-SE direction in its eastern part, where mainly post-rift sediments accumulated. The most distal part reaches the margin slope and opens into the oceanic basin. The general basin direction is almost orthogonal to the present-day margin trend. The most frequent hypothesis explaining this geometry is that the Colorado Basin is an aborted rift resulting from a previous RRR triple junction [e.g. Franke et al., 2002]. The structural interpretation
In 2006, the Argentine Nuclear Regulatory Authority has initiated a regulatory knowledge management process to face the loss of knowledge resulting from retiring experts, the generation gap, and the existing need to train new human resources. A number of projects have been started together with the technical assistance of the National Public Administration Institute to preserve knowledge and render it explicit for the coming generations. These projects include 'The History of the Expert's Learning Process' in which the majority of the most critical experts have been interviewed so far. The results of this project help envision a training structure and prospective projects. An Internet Site has also been created on the Intranet in order to render knowledge explicit and facilitate the tools for knowledge management initiatives. Furthermore, ARN's knowledge map project has also been started. (author)
Brazil has been the most important MERCOSUL's purchaser of fresh onions from Argentina. The increased claim for this fresh product has forced a consensus between the members nations, as regards to phytosanitary restrictions. The radio inhibition is described on National Food Codes in Brazil and Argentina. Methods of food irradiation detection must be performed, since they increase the consumer confidence. Quick and simple screening tests indicate whether a food product has been irradiated or not. This present study verified the DNA fragments of argentine fresh onions, produced during radiation process and 6 months of storage period. The DNA fragments are analyzed for detection of irradiated foods. The irradiated onions presented extensive DNA migrations, as comets, when submitted to agarose gel electrophoresis. They also showed more shelf life compared to the unirradiated onions. The unirradiated samples exhibited only limited DNA migration. This initial screen method showed to be effective for detection of irradiated onions. (author)
This Report describes the actions of the Brazil-Argentine of Accounting and Control of Nuclear Materials (ABACC), during the year of 2003. The developed work allowed to concluded that there is no event indicating that any nuclear material non-accounted for were deviated for non permitted activities by the Agreement for Peaceful Use of Nuclear Energy between Argentine and Brazil and by the Four Parties Agreement among these countries, the ABACC and the International Atomic Energy Agency (IAEA)
Daane, Kent M; Cooper, Monica L; Sime, Karen R; Nelson, Erik H; Battany, Mark C; Rust, Michael K
Liquid baits were evaluated for control of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), and associated mealybug and soft scale pests in California vineyards. In 2003, liquid baits with small doses ofimidacloprid, boric acid, or thiamethoxam dissolved in 25% sucrose water resulted in lower ant and mealybug densities and fruit damage, compared with an untreated control. Similar treatments in a soft scale-infested vineyard showed only a reduction of ant density and fruit infestation in only the boric acid and thiamethoxam treatments. In 2004, commercial and noncommercial formulations of liquid baits reduced ant densities in three separate trials, but they had inconsistent effects on mealybug densities and fruit infestation; granular protein bait had no effect. Using large plots and commercial application methodologies, liquid bait deployed in June resulted in lower ant density and fruit infestation, but it had no effect on mealybug density. Across all trials, liquid bait treatments resulted in lower ant density (12 of 14 trials) and fruit damage (11 of 14 sites), presenting the first report of liquid baits applied using commercial methodologies that resulted in a reduction of ants and their associated hemipteran crop damage. For commercialization of liquid baits, we showed that any of the tested insecticides can suppress Argentine ants when properly delivered in the crop system. For imidacloprid, bait dispensers must be protected from sunlight to reduce photodegradation. Results suggest that incomplete ant suppression can suppress mealybug densities. However, after ant populations are suppressed, there may be a longer period before hemipteran populations are effectively suppressed. Therefore, liquid baits should be considered part of a multiseason program rather than a direct, in-season control of hemipteran pest populations. PMID:18613568
Full Text Available Argentina is among the four largest producers of soybeans, sunflower, corn, and wheat, among other agricultural products. Institutional and policy changes during the 1990s fostered the development of Argentine agriculture and the introduction of innovative process and product technologies (no-till, agrochemicals, GMO, GPS and new investments in modern, large-scale sunflower and soybean processing plants. In addition to technological changes, a "quiet revolution" occurred in the way agricultural production was carried out and organized: from self-production or ownership agriculture to a contract-based agriculture. The objective of this paper is to explore and describe the emergence of networks in the Argentine crop production sector. The paper presents and describes four cases that currently represent about 50% of total grain and oilseed production in Argentina: "informal hybrid form", "agricultural trust fund", "investor-oriented corporate structure", and "network of networks". In all cases, hybrid forms involve a group of actors linked by common objectives, mainly to gain scale, share resources, and improve the profitability of the business. Informal contracts seem to be the most common way of organizing the agriculture process, but using short-term contracts and sequential interfirm collaboration. Networks of networks involve long-term relationships and social development, and reciprocal interfirm collaboration. Agricultural trust fund and investor-oriented corporate structures have combined interfirm collaboration and medium-term relationships. These organizational forms are highly flexible and show a great capacity to adapt to challenges; they are competitive because they enjoy aligned incentives, flexibility, and adaptability.
Full text: Introduction: In commercial aviation the most important determinants of radiation exposure in humans are the altitude, latitude, flight duration and the solar cycle's period. This study was conducted to address this type of exposure trough radiation dosimetry. Method: The study was performed in the business-class cabin of an Airbus 340-200 aircraft, provided by Argentine Airlines, during 2 flights routes: New York-Miami-Buenos Aires (trans equatorial) and Buenos Aires-Auckland (circumpolar). Measurements addressed the electromagnetic spectrum or low Linear Energy Transfer (LET) and corpuscular radiation (High LET). The instruments used were an Ion Chamber (IC), to measure the ionizing component of radiation (i.e., gamma radiation), the SWENDI, to measure only the neutron component, and the Tissue Equivalent Proportional Counter (TEPC) for measuring all radiation types. Results: The routes' dose rates are presented in the table. TEPC rates agreed with the LET findings. The total dose rates of high latitude flights were higher than those of low latitude flights. The SWENDI (High LET) results for the flights over the equator, at low latitude, represented only 1/3 of the total radiation. The New York-Miami and Buenos Aires-Auckland flights, at high latitude, represented just under 1/2 of the Total radiation (-45%). Conclusion: Based on the results of this study, the annual dose rates of radiation exposure of air crew personnel serving on international flights offered by Argentine Airlines is between 3 and 7 mSv. This rate is higher than the maximum recommended for the general population by the International Commission on Radiological Protection (ICRP), which is 1 milli Sv./y. Therefore, these personnel must be officially considered 'Occupationally Exposed to Radiation' in way to provide the appropriate measures that must be implemented for their protection in accordance to ICRP guidelines. Dose(uSv): Route N Y-Miami, IC 6.07, SWENDI 5.07, TEPC 11.04; Route
Full Text Available The Andean foreland of western Argentina (28°S-33°S corresponds to retroarc deformations associated with the ongoing flat subduction of the Nazca plate beneath the South American lithosphere. This region is characterized by high levels of seismic activity and crustal active faulting. To improve earthquake source identification and characterization in the San Juan region, data from seismology, structural geology and quantitative geomorphology were integrated and combined to provide a seismotectonic model. In this seismotectonic model, the Andean back-arc of western Argentina can be regarded as an obliquely converging foreland where Plio-Quaternary deformations are partitioned between strike-slip and thrust motions that are localized on the E-verging, thin-skinned Argentine Precordillera, and the W-verging thick-skinned Sierras Pampeanas, respectively. In this seismotectonic model, the Sierra Pie de Palo appears to be a key structure playing a major role in the partitioning of the Plio-Quaternary deformations.
Industrial gammagraphy has always been responsible for the highest rates of radiological incidents in almost every part of the world. This is mainly due to the high activities of the radioactive sources used, which are constantly transported in the equipment that contains them between the storage and the areas of work, and is also due to work load pressures which may induce to negligence in following the operational procedures, if a strong Safety Culture does not exist. The purpose of this paper is to present the main aspects of the argentine regulations relating to radiation protection to control this practice and to contribute in this way to reduce the associated risks. In addition, some incidents occurred in Argentina during the latest years, the causes that led to those events and their relation to the in observance of the regulations in force, their consequences and the measures taken to repair them are described. Finally, the importance of the role that education and training has in the strengthening of Safety Culture, key element of all undertaking, is highlighted. (author)
Salomon, Oscar D; Fernandez, Maria S; Santini, María S; Saavedra, Silvina; Montiel, Natalia; Ramos, Marina A; Rosa, Juan R; Szelag, Enrique A; Martinez, Mariela F
The first case of visceral leishmaniasis (VL) in Argentina was reported in 2006 in Posadas, Misiones. During the summer 2008-2009 Lutzomyia longipalpis, the VL vector, and canine VL cases were already spread along the province of Corrientes. In order to know the distribution of VL risk, systematic captures of the vector were performed between February and March 2010, in 18 areas of the provinces of Entre Ríos and Corrientes, and the city of Puerto Iguazú, Misiones, with a total of 313 traps/night. We confirmed the presence of Lu. longipalpis, for the first time in Chajarí (Entre Ríos), Alvear, La Cruz, Curuzú Cuatiá and Bella Vista (Corrientes), and Puerto Iguazú (Misiones). In Santo Tome and Monte Caseros (Corrientes), where the vector had been previously reported, traps with more samples were obtained with 830 and 126 Lu. Longipalpis trap/site/night respectively. These results show that the vector of urban VL continues spreading in the Argentine territory. Simultaneously, the spread of the parasite and the resulting human VL cases are associated with the dispersion of reservoirs, infected dogs, with or without clinical symptoms or signs, due to human transit. PMID:21296716
Industrial gammagraphy has always been responsible for the highest rates of radiological incidents in almost every part of the world. This is mainly due to the high activities of the radioactive sources used, which are constantly transported in the equipment that contains them between the storage and the areas of work, and is also due to workload pressures which may induce to negligence in following the operational procedures, if a strong Safety Culture does not exist. The purpose of this paper is to present the main aspects of the Argentine Regulations relating to radiation protection to control this practice and to contribute in this way to reduce the associated risks. In addition, some incidents occurred in Argentina during the latest years, the causes that led to those events and their relation to the in observance of the regulations in force, their consequences and the measures taken to repair them are described. Finally, the importance of the role that education and training has in the strengthening of Safety Culture, key element of all undertaking, is highlighted. (author)
The Argentine nuclear trade regime. Nuclear Materials. Definitions. Stages. From early times of nuclear development an actual and strict monopoly governed the transfers of nuclear materials. That meant: the Federal State took the control as user, producer, purchaser or seller. This policy was inspired and clearly echoed a similar one developed by countries with important development in the nuclear field. Types of contracts on nuclear commerce. Relation with costs implied with the nuclear industry. Uranium mining. System of supplies. Development of factories of nuclear supplies. Incentives. Nuclear Power. Radioisotopes. Human Resources. Ways of intervention of the State on nuclear Commerce. The right of veto. The ownership of shares in private or public corporations. Export- import controls. Security and Safety standards. National Act of Nuclear Activity. Veto of the Executive Power to the monopoly of the exclusive national supply of uranium. Comparative policies on other fields or products in Argentina. A proposal of lege ferenda. State's right of transformation applicable to purchases and sales of nuclear materials. Exchange and loans. Cosignature of contracts, etc. (author)
Hooper-Bui, L. M.; Kwok, E. S. C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.
Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.
Full Text Available This contribution takes up our doctoral research –Argentine migrationto Spain- to share some theoretical-methodological considerations.We refer to the conceptualization of "transnational social spaces," an approach that allows us to consider migration in its double dimension origin/destination and is particularly useful to thing the relationship between migration and creation of social and cultural ties in the Hispano-Argentine or Argentine-Spanish space. Similarly, the transnational spaces approach allows to put in dialog diverse social groups involved in the phenomenon: the migrants themselves, whose life stories are analysed by using oral sources; the society of origin and the host society, analysing collective image through journal sources; the filmmakers, whose migration stories we discussmigration through various fiction films; and, of course, historians and other social scientists who study these migrations.
Brightwell, R J; Bambara, S B; Silverman, J
The invasive Argentine ant, Linepithema humile (Mayr), has become a worldwide problem capable of inflicting significant ecological and economic injury on urban, agricultural, and natural environments. The mobility of this pest ant has long been noted, rapidly moving nests to new food resources and then away as resources are depleted. This ant, like many pest ant species, has a special affinity for honeydew excreted by phloem-feeding Hemiptera. We investigated the effect of various hemipteran control strategies on terrapin scale densities and measured their indirect effect on local Argentine ant densities and foraging effort. We then determined whether this indirect treatment strategy improved the performance of an ant bait. We predicted that Argentine ants would move nests away from trees treated for Hemiptera and then move nests back when a liquid bait was offered, followed by a decline in ant numbers due to intake of the toxicant. A horticultural oil spray and soil application of the systemic insecticide, imidacloprid, had no effect on terrapin scale numbers. However, trunk-injected dicrotophos caused a reduction in scale and a decline in local Argentine ant nest density and canopy foraging effort. We also recorded a reduction in local Argentine ant ground foraging when large amounts of liquid bait were applied, and we found no evidence that combining dicrotophos with liquid ant bait performed better than each treatment alone. We suggest that a strategy of combined hemipteran control plus application of liquid ant bait can reduce local Argentine ant densities, when both components of this system are highly efficacious. PMID:21061981
Full Text Available BACKGROUND: DNA barcoding has been advanced as a promising tool to aid species identification and discovery through the use of short, standardized gene targets. Despite extensive taxonomic studies, for a variety of reasons the identification of fishes can be problematic, even for experts. DNA barcoding is proving to be a useful tool in this context. However, its broad application is impeded by the need to construct a comprehensive reference sequence library for all fish species. Here, we make a regional contribution to this grand challenge by calibrating the species discrimination efficiency of barcoding among 125 Argentine fish species, representing nearly one third of the known fauna, and examine the utility of these data to address several key taxonomic uncertainties pertaining to species in this region. METHODOLOGY/PRINCIPAL FINDINGS: Specimens were collected and morphologically identified during crusies conducted between 2005 and 2008. The standard BARCODE fragment of COI was amplified and bi-directionally sequenced from 577 specimens (mean of 5 specimens/species, and all specimens and sequence data were archived and interrogated using analytical tools available on the Barcode of Life Data System (BOLD; www.barcodinglife.org. Nearly all species exhibited discrete clusters of closely related haplogroups which permitted the discrimination of 95% of the species (i.e. 119/125 examined while cases of shared haplotypes were detected among just three species-pairs. Notably, barcoding aided the identification of a new species of skate, Dipturus argentinensis, permitted the recognition of Genypterus brasiliensis as a valid species and questions the generic assignment of Paralichthys isosceles. CONCLUSIONS/SIGNIFICANCE: This study constitutes a significant contribution to the global barcode reference sequence library for fishes and demonstrates the utility of barcoding for regional species identification. As an independent assessment of alpha
Mabragaña, Ezequiel; Díaz de Astarloa, Juan Martín; Hanner, Robert; Zhang, Junbin; González Castro, Mariano
Background DNA barcoding has been advanced as a promising tool to aid species identification and discovery through the use of short, standardized gene targets. Despite extensive taxonomic studies, for a variety of reasons the identification of fishes can be problematic, even for experts. DNA barcoding is proving to be a useful tool in this context. However, its broad application is impeded by the need to construct a comprehensive reference sequence library for all fish species. Here, we make a regional contribution to this grand challenge by calibrating the species discrimination efficiency of barcoding among 125 Argentine fish species, representing nearly one third of the known fauna, and examine the utility of these data to address several key taxonomic uncertainties pertaining to species in this region. Methodology/Principal Findings Specimens were collected and morphologically identified during crusies conducted between 2005 and 2008. The standard BARCODE fragment of COI was amplified and bi-directionally sequenced from 577 specimens (mean of 5 specimens/species), and all specimens and sequence data were archived and interrogated using analytical tools available on the Barcode of Life Data System (BOLD; www.barcodinglife.org). Nearly all species exhibited discrete clusters of closely related haplogroups which permitted the discrimination of 95% of the species (i.e. 119/125) examined while cases of shared haplotypes were detected among just three species-pairs. Notably, barcoding aided the identification of a new species of skate, Dipturus argentinensis, permitted the recognition of Genypterus brasiliensis as a valid species and questions the generic assignment of Paralichthys isosceles. Conclusions/Significance This study constitutes a significant contribution to the global barcode reference sequence library for fishes and demonstrates the utility of barcoding for regional species identification. As an independent assessment of alpha taxonomy, barcodes provide
Full Text Available Many cattle breeds have been subjected to high selection pressure for production traits. Consequently, population genetic structure and allelic distribution could differ in breeds under high selection pressure compared to unselected breeds. Analysis of k-casein, aS1-casein and prolactin gene frequencies was made for Argentine Creole (AC and Argentine Holstein (AH cattle herds. The calculated FST values measured the degree of genetic differentiation of subpopulations, depending on the variances of gene frequencies.The AC breed had considerably more variation among herds at the aS1-casein and k-casein loci. Conservation strategies should consider the entire AC population in order to maintain the genetic variability found in this native breed.
Fast Breeder Reactors (FBR) main features are presented in a general form, including their physical principles, the history of their evolution, their relevant technological aspects and the basis for their comparison to other energy sources. This is completed with descriptions of typical reactors and a model of FBR penetration in the Argentine electrical network. It is recommended to form a multidisciplinary board to study which position should be taken with respect to this type of reactors. In the author's opinion a Research activity should be started and gradually increased for passing to Development activities after a short while. (Author)
Daniel O. Brasnarof
Full Text Available A new fuel element (called CARA designed for two different heavy water reactors (HWRs is presented. CARA could match fuel requirements of both (one CANDU and one unique Siemens's design Argentine HW reactors. It keeps the heavier fuel mass density and hydraulic flow restriction in both reactors together with improving both thermomechanic and thermalhydraulic, safety margins of present fuels. In addition, the CARA design could be considered as another design line for the next generation of CANDU fuels intended for higher burnup.
Brightwell, R J; Silverman, J
The Argentine ant is well known for its affinity for honeydew and is often associated with hemipteran outbreaks in agricultural and urban environments. It has been suggested that Argentine ants may be controlled by restricting access to honeydew, thereby forcing the ants to move or by encouraging increased liquid toxicant intake. We tested this possible control strategy by restricting Argentine ant access to the honeydew-producing terrapin scale within the canopy of red maple trees and monitoring ant numbers with pitfall traps and nest counts in the mulch around the tree base. Argentine ant nest numbers fell dramatically in the mulch around ant-excluded trees; however, there was no reduction in Argentine ant numbers caught in pitfalls around trees with or without canopy access. We added 0.5% boric acid bait stations at the base of the red maples and monitored bait consumption. Pitfall and nest counts were not affected by the addition of boric acid, although bait consumption was lower around ant-excluded trees, suggesting that restricting access to honeydew-producing Hemiptera did not enhance bait performance. We attribute this result to the increased distance Argentine ant workers had to trail from nest to bait station when not tending nearby terrapin scale. We suggest an alternative management strategy concentrating direct insecticidal control of Argentine ants around a few host plants infested with honeydew-producing Hemiptera by controlling Hemiptera in nearby host plants. PMID:19610434
Argentina has six operating research reactors that can be divided into two groups. The first group comprises the reactors that operate according to a regular schedule, which includes research reactors RA-1, RA-3 and RA-6. The second group comprises the critical assemblies RA-0, RA-4 and RA-8. Another reactor, RA-2, was shut down in 1983, and currently it is in the process of decommissioning. With the exception of RA-4, all Argentine research reactors use fuel elements fabricated in the country. The fuel elements of RA-4 were donated by Germany. What follows is a brief description of all seven Argentinian research reactors
Wossler Theresa C
Full Text Available Abstract Background The Argentine ant, Linepithema humile, is a widespread invasive ant species that has successfully established in nearly all continents across the globe. Argentine ants are characterised by a social structure known as unicoloniality, where territorial boundaries between nests are absent and intraspecific aggression is rare. This is particularly pronounced in introduced populations and results in the formation of large and spatially expansive supercolonies. Although it is amongst the most well studied of invasive ants, very little work has been done on this ant in South Africa. In this first study, we investigate the population structure of Argentine ants in South Africa. We use behavioural (aggression tests and chemical (CHC approaches to investigate the population structure of Argentine ants within the Western Cape, identify the number of supercolonies and infer number of introductions. Results Both the aggression assays and chemical data revealed that the Western Cape Argentine ant population can be divided into two behaviourally and chemically distinct supercolonies. Intraspecific aggression was evident between the two supercolonies of Argentine ants with ants able to discriminate among conspecific non-nestmates. This discrimination is linked to the divergence in cuticular hydrocarbon profiles of ants originating from the two supercolonies. Conclusions The presence of these two distinct supercolonies is suggestive of at least two independent introductions of this ant within the Western Cape. Moreover, the pattern of colonisation observed in this study, with the two colonies interspersed, is in agreement with global patterns of Argentine ant invasions. Our findings are of interest because recent studies show that Argentine ants from South Africa are different from those identified in other introduced ranges and therefore provide an opportunity to further understand factors that determine the distributional and spread
The consolidation of the Argentine Federal Government by the 1870s aimed to modernise local society, establish state institutions and reach political stabilisation. Building a modern schooling system articulated both utopia and bureaucracy by establishing the use of knowledge as an instrument of social intervention, vindicating and legitimising…
Smith, Christopher D; Zimin, Aleksey; Holt, Carson; Abouheif, Ehab; Benton, Richard; Cash, Elizabeth; Croset, Vincent; Currie, Cameron R; Elhaik, Eran; Elsik, Christine G; Fave, Marie-Julie; Fernandes, Vilaiwan; Gadau, Jürgen; Gibson, Joshua D; Graur, Dan; Grubbs, Kirk J; Hagen, Darren E; Helmkampf, Martin; Holley, Jo-Anne; Hu, Hao; Viniegra, Ana Sofia Ibarraran; Johnson, Brian R; Johnson, Reed M; Khila, Abderrahman; Kim, Jay W; Laird, Joseph; Mathis, Kaitlyn A; Moeller, Joseph A; Muñoz-Torres, Monica C; Murphy, Marguerite C; Nakamura, Rin; Nigam, Surabhi; Overson, Rick P; Placek, Jennifer E; Rajakumar, Rajendhran; Reese, Justin T; Robertson, Hugh M; Smith, Chris R; Suarez, Andrew V; Suen, Garret; Suhr, Elissa L; Tao, Shu; Torres, Candice W; van Wilgenburg, Ellen; Viljakainen, Lumi; Walden, Kimberly K O; Wild, Alexander L; Yandell, Mark; Yorke, James A; Tsutsui, Neil D
Ants are some of the most abundant and familiar animals on Earth, and they play vital roles in most terrestrial ecosystems. Although all ants are eusocial, and display a variety of complex and fascinating behaviors, few genomic resources exist for them. Here, we report the draft genome sequence of a particularly widespread and well-studied species, the invasive Argentine ant (Linepithema humile), which was accomplished using a combination of 454 (Roche) and Illumina sequencing and community-based funding rather than federal grant support. Manual annotation of >1,000 genes from a variety of different gene families and functional classes reveals unique features of the Argentine ant's biology, as well as similarities to Apis mellifera and Nasonia vitripennis. Distinctive features of the Argentine ant genome include remarkable expansions of gustatory (116 genes) and odorant receptors (367 genes), an abundance of cytochrome P450 genes (>110), lineage-specific expansions of yellow/major royal jelly proteins and desaturases, and complete CpG DNA methylation and RNAi toolkits. The Argentine ant genome contains fewer immune genes than Drosophila and Tribolium, which may reflect the prominent role played by behavioral and chemical suppression of pathogens. Analysis of the ratio of observed to expected CpG nucleotides for genes in the reproductive development and apoptosis pathways suggests higher levels of methylation than in the genome overall. The resources provided by this genome sequence will offer an abundance of tools for researchers seeking to illuminate the fascinating biology of this emerging model organism. PMID:21282631
Sial, A.N.; Peralta, S.; Gaucher, C.; Toselli, A.J.; Ferreira, V.P.; Frei, Robert; Parada, M.A.; Pimentel, M.M.; Pereira, Natan Silva
We report the occurrence of important carbon isotope excursions in early Paleozoic formations of the Eastern and Central Argentine Precordillera. The Steptoean positive isotope carbon excursion (SPICE) is known from North America, Kazakhstan, South China, Australia and South America, and the nega...
Abstracts are presented at the 81 Annual meeting of the Argentine Physics Association (AFA). The papers can be grouped under the following main topics: teaching, history and philosophy of physics; classical and quantum physics: particles and fields; statistical physics and thermodynamics; nuclear physics; atomic and molecular physics; optic; fluid dynamics and plasmas; condensed matter; instrumentation; geophysics and astrophysics. refs., ills
This document reports activities during the year 2007 related to: technical activities as application of safeguards; management of the Quadripartite Agreement and the SCCC - Common System for Accounting and Control of Nuclear Materials; training; technical cooperation; outlook for 2008 and; institutional, administrative and financial activities; technical glossary; list of brazilian facilities; list of argentine facilities and a list of institution of nuclear area
The privatization of the Argentine oil industry has been described as an unprecedented transfer of property, capital and control from the state to the corporate sphere, but this study demonstrates that the privatization process is better understood as a transformation of the historical configurations of oil-fueled development, political communities and human subjectivities. This dissertation probes the development of the state-led oil industry, and the shift to a corporate-led one, through an ethnography of Argentines differently positioned in relation to the global oil industry. The ethnography explores the lives of middle class oil workers and their families in Northwest Patagonia, impoverished residents of the shanty neighborhoods near the refineries in metropolitan Buenos Aires, and affluent employees of the translocal corporations operating in the Argentine oil fields. After the Introduction delineates this study's four principal interventions into anthropological scholarship, each subsequent chapter engages a particular problem that cuts across the Argentine oil fields and the anthropological theoretical fields. Chapter Two scrutinizes the historical construction of the Argentine subterritory as a "natural" space of value. Chapters Three and Four investigate the articulation of capitalist production and filial reproduction. These chapters argue that sentiment is a crucial generative force that has shaped the oil industry, company towns and worker families from the founding of the state-owned oil company in beginning of the twentieth century to its conversion into a corporate-owned one at the century's close. Chapters Five and Six examine the emergence of consumer citizenship and corporate citizenship out of Argentine neoliberalismo and its transformation of the oil industry. They argue that consumer and corporate citizenship are both reformulations of the older traditions of liberalism and Peronism. All the chapters of this dissertation illustrate that the
Menke, Sean B; Holway, David A
1. A prominent and unresolved question in ecology concerns why communities differ in their susceptibility to invasion. While studies often emphasize biotic resistance, it is less widely appreciated how the physical environment affects community vulnerability to invasion. 2. In this study we performed field experiments to test how abiotic variation directly and indirectly influences the extent to which Linepithema humile Mayr (Argentine ants) invade seasonally dry environments in southern California. 3. In controlled and replicated experiments involving drip irrigation, we demonstrate (i) that elevated levels of soil moisture increased both the abundance of Argentine ants and their ability to invade native ant communities and (ii) that cessation of irrigation caused declines in the abundance of Argentine ants and led to their withdrawal from previously occupied areas. 4. Because drip irrigation stimulated plant growth, in an additional experiment we manipulated both soil moisture and plant cover to assess the direct vs. indirect effects of added water on the abundance of L. humile. 5. Local abundance of Argentine ants increased in irrigated plots but was 38% higher in irrigated plots with plants compared to irrigated plots where plant growth was suppressed. The results of this experiment thus argue for a direct role of soil moisture in influencing Argentine ant abundance but suggest that that the indirect effects of added water may also be important. 6. Our study illustrates more generally that fine-scale variation in the physical environment can control whether communities become invaded by non-native species and suggests that an understanding of community susceptibility to invasion will be improved by a better appreciation of interactions between the biotic and abiotic environment. PMID:16637990
Silverman, Jules; Roulston, T'ai H
Argentine ants, Linepithema humile (Mayr), use mass recruitment foraging, with clumped prey items being retrieved more efficiently than dispersed prey. However, in prior field experiments, granular baits, whether dispensed in containers or broadly scattered, had a similar impact on Argentine ant populations. In laboratory experiments, granular insecticide bait was encountered faster by Argentine ant workers and more granules were initially returned to the colony when the granules were scattered versus clumped. After 2 h, granules from both dispersion patterns were retrieved equally. Our results suggest that Argentine ant colonies adjust their foraging patterns to resources of different quality (prey versus bait). Also, foraging activity patterns for bait in the laboratory are consistent with prior field results demonstrating no efficacy advantages to discrete granular bait placements. PMID:12852629
Silvina Lilian Danesi; Carleton University; Ludovic Rheault; University of Montreal
Latin American legislatures have gone largely unstudied, with the functioning of the Argentine Chamber of Deputies prior to the 1980s being an entirely unexplored subject. This paper fills that gap by examining the organization of the Chamber, with particular focus on its standing committee system from 1946 to 2001. We assess the portability of two U.S.-based theoretical approaches to legislative organization by applying them to committee assignments. An original data set of Argentine deputie...
Kizner, Michelle Cara
In San Diego County, a major economic impact of the Argentine ant occurs in citrus agroecosystems, where ants interfere with biological control of key insect pests, especially California red scale. Ant control is considered a critical component of integrated pest management (IPM) of several citrus pests, but IPM recommendations fail to consider quantitative relationships between levels of Argentine ant abundance and those of the economic pests. This serious gap in understanding impedes develo...
Rowles, Alexei D; Silverman, Jules
Invasive ants are notorious for directly displacing native ant species. Although such impacts are associated with Argentine ant invasions (Linepithema humile) worldwide, impacts within natural habitat are less widely reported, particularly those affecting arboreal ant communities. Argentine ants were detected in North Carolina mixed pine-hardwood forest for the first time but were localized on and around loblolly pines (Pinus taeda), probably because of association with honeydew-producing Hemiptera. We explored the potential impacts of L. humile on arboreal and ground-foraging native ant species by comparing interspersed loblolly pines invaded and uninvaded by Argentine ants. Impacts on native ants were assessed monthly over 1 yr by counting ants in foraging trails on pine trunks and in surrounding plots using a concentric arrangement of pitfall traps at 1, 2, and 3 m from the base of each tree. Of floristics and habitat variables, higher soil moisture in invaded plots was the only difference between plot types, increasing confidence that any ant community differences were caused by Argentine ants. Overall patterns of impact were weak. Composition differed significantly between Argentine ant invaded and uninvaded trunks and pitfalls but was driven only by the presence of Argentine ants rather than any resulting compositional change in native ant species. Native ant abundance and richness were similarly unaffected by L. humile. However, the abundance of individual ant species was more variable. Although numbers of the arboreal Crematogaster ashmeadi (Myrmicinae) declined on and around invaded pines, epigeic Aphaenogaster rudis (Myrmicinae) remained the most abundant species in all plots. Argentine ant densities peaked in late summer and fall, therefore overlapping with most native ants. Unexpected was their continued presence during even the coldest months. We provide evidence that Argentine ants can invade and persist in native North Carolina forests, probably
Nishisue, K; Sunamura, E; Tanaka, Y; Sakamoto, H; Suzuki, S; Fukumoto, T; Terayama, M; Tatsuki, S
Previous short-term experiments showed that trail following behavior of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), can be disrupted by a high concentration of synthetic trail pheromone component (Z)-9-hexadecenal. In this study, a long-term field trial was conducted in 100-m2 plots of house gardens in an urban area of Japan to see whether the control effect on Argentine ants can be obtained by permeating synthetic trail pheromone from dispensers. The dispensers were placed in the experimental plots during the ant's active season (April-November) for 2 yr with monthly renewal. To estimate Argentine ant population density, foraging activity of Argentine ants in the study plots was monitored by monthly bait surveys. Throughout the study period, Argentine ant foraging activity was suppressed in the presence of the dispensers, presumably via trail forming inhibition. In contrast, the level of foraging activity was not different between treatment and no-treatment plots when the dispensers were temporarily removed, suggesting that treatment with pheromone dispensers did not suppress Argentine ant density in the treatment plots. Population decline may be expected with larger-scale treatment that covers a significant portion of the ant colony or with improvement in the potency of the disruptant. PMID:21061980
The two main features of beef from the Argentine Pampas are its quality and geographical origin. In addition to the normal aspects of meat quality detected by sensory panels or measured by scientific instruments, the quality of Pampean beef includes the powerful symbolic quality of pampas life - the immensity of the green grasslands and the culture of the gaucho, living on horseback or sipping mate while making an asado (barbecue). This review defines the qualities and geographical origin of Pampean beef, and explains their interrelationships in terms of animal breed, nutrition and production systems. The objective is to help secure Pampean beef against unfair encroachment from competing products which lack the true authenticity of beef from the Argentine Pampas. PMID:22062914
The 6th Argentine Congress on Radiation Protection and Nuclear Safety was organized by the Radioprotection Argentine Society, in Buenos Aires, between the 22 and 24 of september of 1998. In this event, were presented almost 66 papers in the following sessions, about these subjects: 1.- Safety in nuclear installations. 2.- Control of nuclear material and physical protection of nuclear installations. 3.- Programs of quality assurance. 4.- Training, technical information and public information. 5.- Physical dosimetry. 6.- Physical dosimetry and occupational radiation protection. 7.- Exposure of the natural radiation. 8.- Environmental radiological safety. 9.- Biological effects of the ionizing radiations and biological dosimetry. 10.- Radiological protection of the medical practice and the radiological emergencies. 11.- Radioactive wastes management. 12.- Transport of radioactive materials
In the early 1990's, the Argentine government promoted a framework for productivity-based negotiations between firms and unions at low levels of organization. The policy weakened the industry-wide collective bargaining system, which sets working conditions for all firms in an industry. This paper employs newly developed quantile regression approaches to investigate the effect of union practices on productivity within the context of the reform. The findings show that (i) industry-wide practice...
The aim of this paper is to look for evidence of financial contagion suffered by several countries as a result of the latest Argentine crisis. I focus my attention on a set of countries: Brazil, Mexico, Russia, Turkey, Uruguay, and Venezuela. I also focus exclusively on three financial markets: foreign exchange, stock exchange, and sovereign debt. In order to test the hypothesis of contagion, Vector Autoregression (VAR) models and instantaneous correlation coefficients corrected for het...
Sidney Jard da Silva
Full Text Available This article analyzes the interaction between organized labor and government during reform of the pension system in Argentina. The purpose is to investigate the political and institutional conditions favorable to the inclusion of trade unions in a negotiated pension reform process. The Argentine pattern of union-government interaction was shown to be shaped more by the peculiarities of the decision-making process than by the demands and power of union organizations.
Gallacher, Marcos; Goetz, Stephan J.; Debertin, David L.
In agriculture, studies dealing with the separation of ownership from control have focused on sharecropping, paying little attention to the impact of management and ownership on efficiency. Using Argentine data, this study tests the hypothesis that efficiency is a function of type of management, concentration of ownership, and mechanisms for monitoring managers. Results show that management, ownership and monitoring have a greater impact on marketing efficiency than either on technical or cos...
Smith, Christopher D.; Zimin, Aleksey; Holt, Carson; Abouheif, Ehab; Benton, Richard; Cash, Elizabeth; Croset, Vincent; Currie, Cameron R; Elhaik, Eran; Elsik, Christine G.; Fave, Marie-Julie; Fernandes, Vilaiwan; Gadau, Jürgen; Gibson, Joshua D.; Graur, Dan
Ants are some of the most abundant and familiar animals on Earth, and they play vital roles in most terrestrial ecosystems. Although all ants are eusocial, and display a variety of complex and fascinating behaviors, few genomic resources exist for them. Here, we report the draft genome sequence of a particularly widespread and well-studied species, the invasive Argentine ant (Linepithema humile), which was accomplished using a combination of 454 (Roche) and Illumina sequencing and community-b...
Rodriguez-Cabal, Mariano A.; Stuble, Katharine L.; Nuñez, Martin A.; Sanders, Nathan J.
Although it is increasingly clear that exotic invasive species affect seed-dispersal mutualisms, a synthetic examination of the effect of exotic invasive species on seed-dispersal mutualisms is lacking. Here, we review the impacts of the invasive Argentine ant (Linepithema humile) on seed dispersal. We found that sites with L. humile had 92 per cent fewer native ant seed dispersers than did sites where L. humile was absent. In addition, L. humile did not replace native seed dispersers, as rat...
Ceballos, L. A.; Piccinali, R. V.; BERKUNSKY, I.; Kitron, U.; Gürtler, R. E.
Triatoma infestans (Klug), the most important vector of Chagas disease in southern South America, is a highly domiciliated species with well-known sylvatic foci only in the Bolivian Andean valleys and in the Bolivian Chaco, where melanic insects designated as “dark morphs” were found. After the tentative identification of two melanic bugs collected from parrot nests in a forest reserve in the Argentine Chaco as T. infestans, we conducted an intensive search there using mouse-baited sticky tra...
Filomeno, Felipe Amin
"Since the 1980s, governments and transnational corporations from core countries led by the United States have driven a global upward ratchet of intellectual property protection. In agriculture, this has meant strengthening the rights of seed companies over the plant varieties they develop and curtailing the rights of farmers over the seeds they cultivate. Exceptionally, from the 1990s to 2013, Argentine soy growers overcame the pressures from the seed industry, guaranteeing the right to free...
Donázar, José A.; Travaini, Alejandro; Ceballos, Olga; Delibes, M.; Hiraldo, F.
—Pellets of adult and nestling Great Horned Owls (Bitho tirginianus) were collected at 12 owl territories nearJunin de los Andes (Neuquen, Argentine Patagonia) during the breeding seasons of 1991— 92 and 1994—95. Mammals represented 69% of the total prey items (N = 1324) identified and Reithrodon auritus (16%), Lepuseuwpaeus (12%) and Ctenomys haigi (12%) were the most common species. Anhropods aecounted for 27% of the total prey by numbers. The two main prey items b...
Menke, Sean B.; Holway, D. A.
A prominent and unresolved question in ecology concerns why communities differ in their susceptibility to invasion. While studies often emphasize biotic resistance, it is less widely appreciated how the physical environment affects community vulnerability to invasion. In this study we performed field experiments to test how abiotic variation directly and indirectly influences the extent to which Linepithema humile Mayr (Argentine ants) invade seasonally dry environments in southern California...
Works are presented at the 76 Annual meeting of the Argentine Physics Association. The papers can be grouped under the following main topics: teaching, history and philosophy of physics, mathematical methods, classical and quantum physics, mechanics and fields, statistical physics and thermodynamics, elementary particle physics and fields, nuclear physics, and molecular physics, atomic collisions, optics, fluid dynamics and plasmas, condensed matter, instrumentation, geophysics, astronomy and astrophysics. refs., ills
Martino, Gabriela P.; Quintana, Ingrid M.; Espariz, Martín; Blancato, Victor S.; Gallina Nizo, Gabriel; Esteban, Luis
We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production. PMID:26847907
The incorporation of indigenous territories into the Argentine Republic must be considered as a complex process of colonization which encompassed space, the word and the body. It enabled the dominant settler society to establish socioeconomic and sociocultural hegemony. The example of the Toba community in Clorinda elucidates the extent to which hegemonic worldviews have infiltrated their self-perception and produced the barrio (urban district) and the campo (rural area), as...
Within the frame of the tasks developed by the Argentine-Brazilian Contractors Coordination Committee in the nuclear area, which was at the beginning promoted by the Contractor Committee of the Argentine Association of Nuclear Technology, a working team was created between both countries in order to analyze the existing regulations and the Quality Assurance systems applied in Brazil and Argentina for their nuclear projects. This paper describes the steps to be followed so as to fulfill the compatibility of the rules, quality assurance and firm certification, laboratories, personnel and materials, and the applicable quality assurance programmes. At first, the methodology applied was the collection of the information and the existing regulations in each one of the countries, to exchange them, analyze them and arrange joint meetings and organize a seminar with experts from both countries to develop and discuss the objectives of this working team. As a result of these activities, the criteria adopted will allow, together with another actions, that both Argentine and Brazilian firms make exchanges and integrations in the nuclear field to supply Atucha II and Angra II. (Author)
This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.
Marino, Armando Carlos; Pérez, Edmundo; Adelfang, Pablo
The irradiation of the first Argentine prototypes of pressurized heavy water reactor (PHWR) (U,Pu)O 2 MOX fuels began in 1986. These experiments were carried out in the High Flux Reactor (HFR)-Petten, Holland. The rods were prepared and controlled in the CNEA's α Facility. The postirradiation examinations were performed in the Kernforschungszentrum, Karlsruhe, Germany and in the Joint Research Center (JRC), Petten. The first rod has been used for destructive pre-irradiation analysis. The second one as a pathfinder to adjust systems in the HFR. Two additional rods including iodine doped pellets were intended to simulate 15 000 MWd/T(M) burnup. The remaining two rods were irradiated until 15 000 MWd/T(M). One of them underwent a final ramp with the aim of verifying fabrication processes and studying the behaviour under power transients. BACO (BArra COmbustible) code was used to define the power histories and to analyse the experiments. This paper presents a description of the different experiments and a comparison between the results of the postirradiation examinations and the BACO outputs.
Within the framework of the RERTR Program and supported by the technical cooperation work agreed upon between the U.S.A. and Argentina in May 1979, the CNEA Nuclear Fuel Department - Low Enriched Fuel Elements Project (ECBE Project), has carried on its own program for developing fuels with low enrichment for research and test reactors. Up to the present, its main objective has been to replace the highly enriched fuel used in its only reactor (RA-3) for research, development and radioisotopes production. The basic stages of the Argentine Program are shown in Table 1. At a meeting held in Vienna in March, 1980, the CNEA stated that its development of fuels with low enrichment would be in two fuel lines: UAlx-Al and U3O8-Al, and that its aim would be to reach uranium densities of 18-2.2 g/cm3 for the UAIx-Al line and 2.4-3.0 g/cm3 for the U3O8 line. At the international meeting held at ANL in November, 1980, and after having received depleted uranium and uranium with 20% and 45% enrichment (purchased from the U.S.A. for manufacturing miniplates and possible standard fuels) to carry on the proposed development, CNEA anticipated -- after its first tests -- that the conditions were satisfactory for reaching uranium densities of 2.4-3.0 g/cm3 in U3O8-Al fuel and of 2.4 g/cm3 in UAIx-Al fuel. In February 1981, after Argentina accepted the obligation of paying for the irradiation service, authorization was obtained for irradiating miniplates in the Oak Ridge Reactor within the RERTR Program. In June 1981, the first set of miniplates was sent to Oak Ridge National Laboratory (ORNL). The maximum actual densities reached at that time were 3.12 g/cm3 with U3O8-Al and 2.52 g/cm3 with UAlx-Al. During a visit of the CNEA Project Technical Manager to the Argonne National Laboratory (ANL) in July 1981, and after exchanging ideas with ANL professional staff, the CNEA decided to incorporate a new line of development, that of U3Si-Al. Three months later, in October 1981 a second set of
A model for the evolution of Argentine's installed nuclear power for the next 40 years is presented. The consequences of fast breeder reactors' introduction are studied in both autarchic Pu cycle and a limited reprocessing system. The passage of a reactor park like the national, of natural U - heavy water to one of fast breeder reactors, can only be obtained in a very long term due, fundamentally, to the need of Pu produced for those to feed the last ones. (M.E.L.)
González Paula LM
Full Text Available Abstract Background Oligoryzomys longicaudatus (colilargo is the rodent responsible for hantavirus pulmonary syndrome (HPS in Argentine Patagonia. In past decades (1967–1998, trends of precipitation reduction and surface air temperature increase have been observed in western Patagonia. We explore how the potential distribution of the hantavirus reservoir would change under different climate change scenarios based on the observed trends. Methods Four scenarios of potential climate change were constructed using temperature and precipitation changes observed in Argentine Patagonia between 1967 and 1998: Scenario 1 assumed no change in precipitation but a temperature trend as observed; scenario 2 assumed no changes in temperature but a precipitation trend as observed; Scenario 3 included changes in both temperature and precipitation trends as observed; Scenario 4 assumed changes in both temperature and precipitation trends as observed but doubled. We used a validated spatial distribution model of O. longicaudatus as a function of temperature and precipitation. From the model probability of the rodent presence was calculated for each scenario. Results If changes in precipitation follow previous trends, the probability of the colilargo presence would fall in the HPS transmission zone of northern Patagonia. If temperature and precipitation trends remain at current levels for 60 years or double in the future 30 years, the probability of the rodent presence and the associated total area of potential distribution would diminish throughout Patagonia; the areas of potential distribution for colilargos would shift eastwards. These results suggest that future changes in Patagonia climate may lower transmission risk through a reduction in the potential distribution of the rodent reservoir. Conclusion According to our model the rates of temperature and precipitation changes observed between 1967 and 1998 may produce significant changes in the rodent
The CAREM 25 reactor project is a small PWR nuclear power plant of 27 MWe, based on advanced concepts: a self-pressurized integral primary with natural convection of the coolant and a more simple and reliable general design. The CAREM concept has many advantages as a power generator in small electrical grids. Besides, there are some non-electrical applications under consideration, since a co-generation scheme seems very interesting from the economical point of view. In this category two alternatives have been considered: a standard desalination facility and a process plant in the mining industry. In this paper, a conceptual analysis of the second alternative is presented. Mining is a branch of the domestic industry that has shown a remarkable growth in the past three years mainly due to a steady inflow of foreign investments (about two billion dollars for that period). And one of the most attractive markets is in the extraction and manufacturing of non-ferrous minerals, coming from deposits in the northwest of Argentina: sodium sulfate, lithium salts, and boron compounds. Nevertheless it faces an unsolved problem in the energy high prices due to the fact that the production sites are located in remote areas where the only achievable energy source is the transportation of fuel oil. In this scenario, a small NPP may be a competitive source of process heat and electricity, with enough autonomy to uncouple fuel requirements from production strategies. The present study analyses the possible application of the CAREM concept in the non-ferrous mining industry of the Northwest of Argentina, considering a co-generation scheme. The main results of this analysis and the inherent advantages of the approach, show that the alternative may be feasible both from the technical and the economical points of view. (author)
Manrique, Elizabeth; Enfield, N. J.
Practices of other-initiated repair deal with problems of hearing or understanding what another person has said in the fast-moving turn-by-turn flow of conversation. As such, other-initiated repair plays a fundamental role in the maintenance of intersubjectivity in social interaction. This study finds and analyses a special type of other-initiated repair that is used in turn-by-turn conversation in a sign language: Argentine Sign Language (Lengua de Señas Argentina or LSA). We describe a type...
Montiel, Marta Soler
L’agriculture urbaine prétend répondre efficacement aux défis de la crise globale actuelle en apportant des emplois et des revenus à ceux qui travaillent la terre, des aliments sains et durables à ceux qui mangent les produits, et des services environnementaux à l’ensemble des citoyens. Dans la ville argentine de Rosario (province de Santa Fe), pour faire face à la crise de 2001, l’agriculture urbaine est passée du stade d’alternative agronomique et socioéconomique proposée par l’agroécologie...
ANA MARÍA ROMERO MARTÍNEZ
Full Text Available In this paper we analyze the intentions in creating a business on the part of a group of Argentine students in Strategic Human Resources Management in the University of Buenos Aires. The results of the study show that these students want to create their own business, but their possibilities depend on several factors. Among all of them, self-effi cacy stands out; those students who show more self-effi cacy are those who demonstrate more intention for creating a business. This intention is minor for the students who possess more social support. Neither family charges nor previous experience in entrepreneurship have a signifi cant effect.
Travaini, Alejandro; Donázar, José A.; Ceballos, Olga; Rodríguez, Alejandro; Hiraldo, F.; Delibes, M.
We evaluated the diet of Common Barn-owls (Tyto alba) along an elevational gradient in Argentine Patagonia. Small mammals (mainly rodents) were the main prey accounting for 93.2% of total prey items. Consumption of rodents appeared to be dependent on their availability. Sizes of mam malian prey were variable but most ranged from 10—100 g in body mass. We concluded that the diet of these barn owls could be used as an index of cricetid rodent populations along ...
Walter C.Sweet; Guillermo L.Albanesi
@@ Present work demonstrates that a level equivalent to the proposed Whiterockian basal GSSP can be located graphically in a composite section anchored by the Niquivil section of the Argentine Precordillera. The FAD of Cooperignathus aranda in the Niquivil composite section, a candidate for GSSP of the Lower/Middle Ordovician boundary, projects to a level very close to the FAD of Tripodus laevis in the Whiterockian reference section. The conodont-based framework reported here includes the potential for recognition of the proposed Whiterock Canyon-based GSSP, the Cooperignathus aranda-based GSSP, and, possibly, the Baltoniodus triangularisbased GSSP, recently proposed.
Silverman, J; Roulston, T H
Liquids and gels are common delivery forms used in commercial ant baits, but the relative effectiveness of each is unknown. We compared the feeding responses of the Argentine ant, Linepithema humile (Mayr), to liquid and gel compositions of sucrose. In choice assays, more workers were counted on gel than liquid; however, substantially more liquid was consumed. Because workers could stand on the gel, more workers could feed simultaneously on the gel. The feeding bouts of individual workers, however, were much less efficient at extracting sucrose in gel form. Workers fed eightfold longer on the gel, yet removed fivefold less sucrose than workers feeding on liquid. This potential bias should be considered during attraction and palatability studies that use physically different bait compositions. When the toxicant fipronil was added to the compositions, a greater proportion of the colony died after workers had fed on liquid than gel baits. This finding suggests that liquid formulations may provide more effective control of Argentine ants due to the greater speed and abundance in which it is ingested. PMID:11332847
Nelson, Erik H; Daane, Kent M
Argentine ants, Linepithema humile (Mayr), have a positive effect on populations of mealybugs (Pseudococcus spp.) in California vineyards. Previous studies have shown reductions in both ant activity and mealybug numbers after liquid ant baits were deployed in vineyards at densities of 85-620 bait stations/ha. However, bait station densities may need to be bait stations/ha before bait-based strategies for ant control are economically comparable to spray-based insecticide treatments-a condition that, if met, will encourage the commercial adoption of liquid baits for ant control. This research assessed the effectiveness of baits deployed at lower densities. Two field experiments were conducted in commercial vineyards. In experiment 1, baits were deployed at 54-225 bait stations/ha in 2005 and 2006. In experiment 2, baits were deployed at 34-205 bait stations/ha in 2006 only. In both experiments, ant activity and the density of mealybugs in grape fruit clusters at harvest time declined with increasing bait station density. In 2005 only, European fruit lecanium scale [Parthenolecanium corni (Bouché)] were also present in fruit clusters, and scale densities were negatively related to bait station density. The results indicate that the amount of ant and mealybug control achieved by an incremental increase in the number of bait stations per hectare is constant across a broad range of bait station densities. The results are discussed in the context of commercializing liquid ant baits to provide a more sustainable Argentine ant control strategy. PMID:18284776
Full Text Available The therapeutic effects of Argentine propolis ear drop formulation on canine otitis externa were evaluated. Forty-eight dogs with symptoms of otitis externa were randomly assigned to double-blinded, controlled clinical trial to evaluate the efficacy of topical formulation with propolis versus a topical placebo in the treatment of otitis externa. The propolis preparation and placebo were administrated into both external ear canals, twice daily for 14 days. Throughout the study, clinical examination and microbiological analysis of dogs ear exudates were made. The most frequent microorganisms isolated in culture media were: Malassezia pachydermatis (54.2%, Staphylococcus aureus (43.8%, coagulase-negative Staphylococcus (25.0%, Pseudomonas aeruginosa (20.8%, Candida albicans (18.8%, Proteus mirabilis (16.7%, Streptococcus spp. (16.7%, Enteroccocus faecalis (12.5%, Escherichia coli (12.5%, Staphylococcus intermedius (6.3%, Klebsiella spp. (4.2%, andCandida glabrata (2.1%. Whereas the control group did not recover from the infectious ear disease, the propolis preparation exhibited antimicrobial activity against most of the microorganisms isolated from samples of the treated group. In addition, no propolis-adverse effects were observed. This allowed propolis-treated patients to show a significant improvement of the clinical parameters. Thus, this new Argentine propolis ear drop formulation may be used for topical treatment of otitis externa in dogs.
Peter J Ross
Full Text Available This paper examines the liberal grounded provincial societies of Argentina from 1890 to 1940. A close examination of provincial government expenditures reveals that these states spent most of their revenues on law and order and education with little being directed to social welfare and to health. This form of government was extremely limited, therefore, in providing for the welfare of most of its citizens, and left many of them excluded from full participation in the political, economic and social life of the nation. The type of liberalism espoused by the Argentine elites effectively undermined the very project of state building that they espoused and resulted in the Peronist revolution of the 1940s when the state, under the slogan of social justice, became much more interventionist in the areas of welfare, health and housing, and much more inclusionist with regard to the Argentine people as a whole. The liberal state, and this includes the provinces, became a victim of its own chosen limitations.
Full Text Available Truth-finding trials (juicios por la verdad constitute a novel solution devised by the Argentine judicial system to cope with crimes committed by the past military dictatorship. This mechanism uses criminal courts as well as criminal procedure in order to investigate the truth about the dictatorship's crimes; however, the trials allow judges neither to establish criminal responsibility nor to punish the perpetrators of crimes. This limitation is due to the inability, imposed by the Full Stop and Due Obedience Laws, to prosecute the perpetrators of crimes.From the perspective of criminal law, truth-finding trials present two problematic features: firstly, their creation and regulation are set by judges, which has caused the development of many non-homogeneous local solutions and, secondly, their hybrid nature, which entails a possible subversion of conventional forms and goals in the context of the criminal trial.The paper also describes the current situation, since the Argentine impunity laws were declared unconstitutional and criminal proceedings reopened. The new framework provokes questions about the relationship between the reopened criminal trials and the truth-finding investigations, not only with regard to evidentiary issues but also with respect to the reason why the truth-finding investigations are still held.Finally, the shift from a non-punitive approach to the current full criminal accountability seems to suggest that truth-finding trials were merely a temporary solution, while the notion of the full prosecution and punishment of State crimes was never really set aside.
Ordóñez, R M; Zampini, I C; Moreno, M I Nieva; Isla, M I
The antimicrobial activity of samples of Northern Argentine propolis (Tucumán, Santiago del Estero and Chaco) against phytopathogenic bacteria was assessed and the most active samples were identified. Minimal inhibitory concentration (MIC) values were determined by agar macrodilution and broth microdilution assays. Strong antibacterial activity was detected against Erwinia carotovora spp carotovora CECT 225, Pseudomonas syringae pvar tomato CECT 126, Pseudomonas corrugata CECT 124 and Xanthomonas campestris pvar vesicatoria CECT 792. The most active propolis extract (Tucumán, T1) was selected to bioguide isolation and identified for antimicrobial compound (2',4'-dihydroxychalcone). The antibacterial chalcone was more active than the propolis ethanolic extract (MIC values of 0.5-1 μg ml(-1) and 9.5-15 μg ml(-1), respectively). Phytotoxicity assays were realized and the propolis extracts did not retard germination of lettuce seeds or the growth of onion roots. Propolis solutions applied as sprays on tomato fruits infected with P. syringae reduced the severity of disease. Application of the Argentine propolis extracts diluted with water may be promising for the management of post harvest diseases of fruits. PMID:21237629
Abdala, Manuel A. [LECG, LLC, 1725 Eye St NW - Suite 800, Washington, DC 20006 (United States)
The Argentine electricity reform of 1992 offers an interesting example of decentralized transmission pricing arrangements within a competitive system. This paper is a shortened version of an original analysis made in 1994 of the regulation of the Argentine transmission system, with emphasis on investment cost allocation rules. To make up for the limitation of short-run marginal cost (SRMC) pricing, incentives on service quality were put in place, including penalties for lack of line availability. The mechanism for capacity expansion, based on ad-hoc rules for allocations of investment costs, had the potential to produce non-optimal investment outcomes, as such rules ignored beneficiaries on the demand side. For fine tuning of this system, I proposed an alternative rule based on traditional welfare analysis that broadens the universe of identified beneficiaries, and thus can be expected to produce a fairer outcome on investment cost allocation, reducing the potential risks of non-optimal investment. A brief postscript comments on the paper from the perspective of 2007. (author)
The Argentine electricity reform of 1992 offers an interesting example of decentralized transmission pricing arrangements within a competitive system. This paper is a shortened version of an original analysis made in 1994 of the regulation of the Argentine transmission system, with emphasis on investment cost allocation rules. To make up for the limitation of short-run marginal cost (SRMC) pricing, incentives on service quality were put in place, including penalties for lack of line availability. The mechanism for capacity expansion, based on ad-hoc rules for allocations of investment costs, had the potential to produce non-optimal investment outcomes, as such rules ignored beneficiaries on the demand side. For fine tuning of this system, I proposed an alternative rule based on traditional welfare analysis that broadens the universe of identified beneficiaries, and thus can be expected to produce a fairer outcome on investment cost allocation, reducing the potential risks of non-optimal investment. A brief postscript comments on the paper from the perspective of 2007. (author)
Full Text Available La question des autochtones est devenue, durant les deux dernières décennies, une préoccupation majeure dans différents pays du monde, comme en Argentine où environ 600 000 individus se reconnaissent comme tels, soit 1,5 % de sa population totale. Toutefois, ces populations sont encore trop souvent marginalisées à l’échelle de certaines régions, comme c’est le cas pour les Mapuche du Parc National Nahuel Huapi, situé dans les provinces du Rio Negro et de Neuquén. Si les textes internationaux et parfois nationaux réhabilitent certains droits humains essentiels de ces populations, les réalités locales sont plus contrastées, du fait d’intérêts souvent divergents des acteurs régionaux. Dans le contexte particulier d’une Argentine marquée par des difficultés d’accès à la propriété foncière pour une large part de la population, les parcs nationaux se révèlent être des outils pertinents, pour les populations autochtones, de recouvrement de leurs terres ancestrales, grâce en particulier aux processus de co-gestion participative mise en place sur ces territoires.
Blanco, Gabriela S.; Quintana, Flavio
To study habitat use and at-sea movements of southern giant petrels (SGP) during non-breeding period, we deployed 15 satellite transmitters (six adults, nine juveniles) at Isla Arce and Isla Gran Robredo colonies in Patagonia, Argentina. Birds were instrumented during 81.4 ± 37 days. Adult birds used 74% of the Argentine shelf concentrating mainly at the shelf break, middle shelf waters, and the surroundings of the colony. After fledging, juveniles spread to the Argentine, Uruguayan and Brazilian shelves within the South Atlantic. Adults alternated at-sea excursions (12 ± 5 days) with periods at the colony of 3 ± 0.3 days. Contrarily, juveniles moved first to the shelf break and then traveled northwards reaching the south of Brazil. There was some spatial overlap between age classes, but only during the first 30 days after juveniles had fledged; thereafter there was not overlap between the areas used by both age classes. The Argentine shelf is widely used by different species offering a suitable environment for foraging; this may be why adults SGP from Patagonian colonies spend all year-round within the Argentine shelf. The identification of used areas of non-breeding SGP fills a gap in the species knowledge contributing not only to the preservation the species, but also to the management of marine areas globally recognized as important for many other Procellariiformes.
Full Text Available Data from five protein-coding loci related to dairy production were used to study the genetic diversity and population structure of Argentine and Bolivian Creole cattle breeds. Genomic DNA was extracted from blood samples of six Creole cattle breeds: Argentine (n = 230, Patagonian (n = 25; "Saavedreño" (n = 140, "Chaqueño Boliviano" (n = 30, "Yacumeño" (n = 27, and "Chusco" (n = 11. kappa-casein, beta-lactoglobulin, growth hormone and prolactin were measured by PCR-RFLP, while alphaS1-casein was typed by PCR-ASO. The results are discussed, focusing on: historical origin, recent differentiation and selection events, Zebu gene introgression, and population structure. This work shows that: (i For the studied genes, the observed gene frequency profiles of Argentine and Bolivian Creole cattle breeds were close to the data reported for Iberian breeds and for other South-American Creole cattle breeds which are historically related; (ii although Zebu gene introgression has been reported at the studied loci, these breeds seem to be far from the Zebu gene frequency profiles; and (iii the Argentine and Bolivian Creole cattle showed significant levels of subdivision, but each population has maintained its degree of genetic variability.
To study the properties of the materials under irradiation, devices and facilities were designed to work at experimental reactors of National Atomic Energy Commission. The radiological protection of the operators and the influence of the irradiated materials on the radiological inventory of the reactors were the most important aspects considered during the design stage. In the present work devices to operate in the argentine reactor 'Reactor Argentino (RA)', RA1 and RA3 experimental reactors are shown. These devices are dedicated to the study of the radiation damage by measuring property changes related to dimensional integrity and embrittlement of materials in zirconium alloys, steels and other materials used in nuclear reactors. The emphasis is on the previsions adopted to minimize the activation of their components and the criteria applied to guarantee the safety of the operators during their performance and after their subsequent dismantling. (author)
Ledesma, Rubén D; Sánchez, Roberto; Díaz-Lázaro, Carlos M
The aim of this work was to develop an adjective checklist to assess the Big Five personality factors in the Argentine population. The new instrument was administered to pilot (n= 112), validation (n= 372), and replication (n= 309) samples. The final version of the checklist included 67 adjectives encompassing its 5 dimensions. Factor analysis results were consistent with the Five-factor model. Internal consistency of scales was very good and convergent correlations with the Big Five Inventory (BFI; John, Donahue, & Kentle, 1991) were substantial. Face validity, as evaluated by 2 independent raters, was good. Preliminary evidence of validity for the checklist is presented. Finally, the Adjective Checklist for Personality Assessment and BFI are compared, taking into consideration their psychometric properties in our cultural context. Study limitations and future research are discussed. PMID:21184330
Vogel, Valérie; Pedersen, Jes S; d'Ettorre, Patrizia;
analyses revealed the presence of 11 supercolonies (width 1 to 515 m) over a 3-km transect. As in the introduced range, there was always strong aggression between but never within supercolonies. The genetic data were in perfect agreement with the behavioral tests, all nests being assigned to identical......Some introduced ant populations have an extraordinary social organization, called unicoloniality, whereby individuals mix freely within large supercolonies. We investigated whether this mode of social organization also exists in native populations of the Argentine ant Linepithema humile. Behavioral...... units. Genetic and chemical distances between supercolonies were positively correlated, but there were no other significant associations between geographic, genetic, chemical, and behavioral distances. A comparison of supercolonies sampled in 1999 and 2005 revealed a very high turnover, with about one...
Latimori, N J; Kloster, A M; García, P T; Carduza, F J; Grigioni, G; Pensel, N A
Steers of varying genotypes (Aberdeen Angus, Charolais x AA and Argentine Holstein) in four feeding systems were evaluated. Feeding systems were: S1=a diet based on pastures only; S2=a similar forage base as S1 plus a daily supplementation with cracked corn, at 0.7% of l.w./head/day; S3=a similar forage base as S1 plus a daily supplementation with cracked corn, at 1.0% of l.w./head/day; and S4=a regular feedlot diet. Tenderness and marbling were not affected by the feeding system. Feedlot meat showed an n-6/n-3 ratio significantly higher than meat produced with the diets based on pastures (S1=2.1; S2=3.1; S3=4.5; S4=14.2) (Pmeat with better nutritional characteristics than other productive alternatives, without significant effects of the biotypes. PMID:22062907
Wernick, Morena B; Novo-Matos, José; Ebling, Alessia; Kühn, Karolin; Ruetten, Maja; Hilbe, Monika; Howard, Judith; Chang, Rita; Prohaska, Sarah; Hatt, Jean-Michel
An Argentine boa (Boa constrictor occidentalis) of 5 yr 7 mo of age was presented for respiratory problems and regurgitation. Radiographs revealed evidence of cardiomegaly and pneumonia. Blood smear examination revealed the presence of intracytoplasmic inclusion bodies in peripheral lymphocytes, consistent with inclusion body disease. Cultures of a tracheal wash sample resulted in growth of Ochrobactrum intermedium and Pseudomonas putida. Echocardiographic examination revealed a large vegetative lesion on the right atrioventricular valve with valvular insufficiency, a mildly dilated right atrium, and pulmonary hypertension. Postmortem examination confirmed the presence of pneumonia and bacterial endocarditis with dystrophic mineralization of the right atrioventricular valve, associated with different bacteria than those cultured from the tracheal wash. The present case is the first report of endocarditis in a boa constrictor and contributes to the rare reports of cardiac disease in snakes. PMID:25831585
The growth of telemedical applications and electronic transactions in health environments is paced by the constant technology evolution. This implies a big cultural change in traditional medicine and in hospital information systems' users which arrival is delayed, basically, by the lack of solid laws and a well defined role-based infrastructure. The use of digital signature as a mean of identification, authentication, confidentiality and non-repudiation is the most suitable tool for assuring the electronic transactions and patient's data protection. The implementation of a Public Key Infrastructure (PKI) in health environment allows for authentication, encryption and use of digital signature for assuring confidentiality and control of the movement of sensitive information. This work defines the minimum technological, legal and procedural basis for a successful PKI implementation and establishes the roles for the different actors in the chain of confidence in the public health environment of Argentine
C’est en 1968 que Copi (Raúl Damonte Botana, 1939-1987) publie sa première pièce, La journée d’une rêveuse puis, un an plus tard, la très iconoclaste Eva Peron. Par son milieu familial, Copi a baigné dès l’enfance dans la vie théâtrale internationale et a été fortement influencé par sa grand-mère, la dramaturge anarcho-féministe Salvadora Medina Onrubia de Botana. Mais, vivant en exil avec sa famille, Copi est coupé de la réalité de la scène argentine et il écrit d’ailleurs ses premières pièc...
Suremain, Charles-Édouard de
L’étude anthropologique des pratiques alimentaires de migrants boliviens de retour ayant longuement séjourné en Argentine permet d’aborder la problématique de la migration et de l’identité : la construction sociale, réelle et imaginaire, de la migration ne passe-t-elle pas aussi par l’alimentation ? Ce que l’on mange ici et là-bas éclaire, en creux, le succès ou l’échec donné à la migration par les migrants et aide à comprendre plus finement les significations locales données à la pauvreté et...
Cretton, M.; Rost, E.; Mazzuca Sobczuk, T.; Mazzuca, M.
The fish processing operations in Patagonia produce large amounts of waste. The main fishery resource in Argentina is the Argentine hake (Merluccius hubbsi). The ports of the province of Chubut (the most important of which are Puerto Madryn, Rawson and Comodoro Rivadavia), together with Caleta Paula Port (province of Santa Cruz), in the Argentine Patagonia, capture more than 82,000 tons of hake annualy, 80% of which are of M. hubbsi, which is mostly converted into fillets. From this capture, ...
Choe, Dong-Hwan; Vetter, Richard S; Rust, Michael K
A novel bait station referred to as a virtual bait station was developed and tested against field populations of the invasive Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), at White Beach, Camp Pendleton, in Oceanside, CA. White Beach is a nesting habitat for an endangered seabird, the California least tern (Sterna antillarum browni Mearns). The beach is heavily infested with Argentine ants, one of the threats for the California least tern chicks. Conventional pest control strategies are prohibited because of the existence of the protected bird species and the site's proximity to the ocean. The bait station consisted of a polyvinyl chloride pipe that was treated on the inside with fipronil insecticide at low concentrations to obtain delayed toxicity against ants. The pipe was provisioned with an inverted bottle of 25% sucrose solution, then capped, and buried in the sand. Foraging ants crossed the treated surface to consume the sucrose solution. The delayed toxicity of fipronil deposits allowed the ants to continue foraging on the sucrose solution and to interact with their nestmates, killing them within 3-5 d after exposure. Further modification of the bait station design minimized the accumulation of dead ants in the sucrose solution, significantly improving the longevity and efficacy of the bait station. The virtual bait station exploits the foraging behavior of the ants and provides a low impact approach to control ants in environmentally sensitive habitats. It excluded all insects except ants, required only milligram quantities of toxicant, and eliminated the problem of formulating toxicants into aqueous sugar baits. PMID:21061977
We studied the effect of estimated PM10 on respiratory infections in children from Cordoba, Argentine as well as the influence of weather factors, socio-economic conditions and education. We analyzed upper and lower respiratory infections and applied a time-series analysis with a quasi-Poisson distribution link function. To control for seasonally varying factors we fitted cubic smoothing splines of date. We also examined community-specific parameters and differences in susceptibility by sex. We found a significant association between particles and respiratory infections. This relationship was affected by mean temperature, atmospheric pressure and wind speed. These effects were stronger in fall, winter and spring for upper respiratory infections while for lower respiratory infections the association was significant only during spring. Low socio-economic conditions and low education levels increased the risk of respiratory infections. These findings add useful information to understand the influence of airborne particles on children health in developing countries. - Highlights: ► Few information is available on children respiratory health from developing countries. ► We modeled the association between PM10 and children's respiratory infections. ► We checked the influence of weather factors, socio-economic conditions, education and sex. ► Temperature, pressure and wind speed modified the effect of particles. ► Low socio-economic conditions and low education levels increased the risk of infections. - The concentration of airborne particles as well as low socio-economic conditions and low education levels are significant risk factors for upper and lower respiratory infections in children from Cordoba, Argentine.
Laura M Blandy
Full Text Available Background: Individuals living with Parkinson’s disease (PD can experience a range of movement disorders. Therapeutic dance is enjoyable and thought to improve mobility, balance and well being in some people with PD. The primary objective of this study was to evaluate the feasibility and safety of a 4 week Argentine tango dance program for people with PD. Methods: Six community dwelling individuals with mild-moderate PD were recruited from Parkinson’s support groups, movement disorder clinics and the Parkinson’s disease Association in Australia. To minimise falls risk, participants were required to be less than 75 years of age and physically independent (Hoehn and Yahr stages I-III. They were also required to speak English. Participants attended a 1 hour dance class at a dance studio twice per week for 4 weeks. A professional dance instructor led and choreographed the classes. Physiotherapists were present to assist participants during the class and served as dance partners as necessary. The primary outcome was feasibility which was determined by measures of recruitment, adherence, attrition, safety (falls, near misses and adverse events and resource requirements. Secondary measures included the Beck Depression Inventory and the Euroqol-5D, administered at baseline and post intervention. Therapy outcomes pre and post-intervention were analysed descriptively as medians and inter-quartile ranges and using Wilcoxon matched pair signed-rank tests.Results: The Argentine tango dance intervention was shown to be safe, with no adverse events. Adherence to the dance program was 89%. Depression scores improved after intervention (p=0.04. Some challenges were associated with the need to quickly recruitment participants and supplying physiotherapists to act as dance partners. Conclusion: The program was shown to be feasible and safe for people with mild to moderately severe PD.
Hanna, Cause; Naughton, Ida; Boser, Christina; Alarcón, Ruben; Hung, Keng-Lou James; Holway, David
Ants often visit flowers, but have only seldom been documented to provide effective pollination services. Floral visitation by ants can also compromise plant reproduction in situations where ants interfere with more effective pollinators. Introduced ants may be especially likely to reduce plant reproductive success through floral visitation, but existing experimental studies have found little support for this hypothesis. Here, we combine experimental and observational approaches to examine the importance of floral visitation by the nonnative Argentine ant (Linepithema humile) on plant species native to Santa Cruz Island, California, USA. First, we determine how L. humile affects floral visitor diversity, bee visitation rates, and levels of pollen limitation for the common, focal plant species island morning glory (Calystegia macrostegia ssp. macrostegia). Second, we assess the broader ecological consequences of floral visitation by L. humile by comparing floral visitation networks between invaded and uninvaded sites. The Argentine ant and native ants both visited island morning glory flowers, but L. humile was much more likely to behave aggressively towards other floral visitors and to be the sole floral occupant. The presence of L. humile in morning glory flowers reduced floral visitor diversity, decreased rates of bee visitation, and increased levels of pollen limitation. Network comparisons between invaded and uninvaded. sites revealed differences in both network structure and species-level attributes. In. invaded sites, floral visitors were observed on fewer plant species, ants had a higher per-plant interaction strength relative to that of other visitors, and interaction strengths between bees and plants were weaker. These results illustrate that introduced ants can negatively affect plant reproduction and potentially disrupt pollination services at an ecosystem scale. PMID:26236907
Full Text Available La fin de la Seconde Guerre Mondiale et la condamnation internationale de l’Espagne plongent le régime franquiste dans une situation très délicate. Cependant, le gouvernement argentin du général Peron devient un véritable gilet de sauvetage pour la dictature espagnole. Le régime du Caudillo profite de ce contexte pour développer une propagande très intense dans le Rio de la Plata. Pour mener à bien les différentes actions de propagande, les représentants espagnols en Argentine devront lutter contre les activités antifranquistes des exilés.La conclusión de la Segunda Guerra Mundial y la condena internacional de España sumen al régimen franquista en una muy delicada coyuntura. Sin embargo, el gobierno argentino del general Perón se convierte en un auténtico chaleco salvavidas para la dictadura española. El régimen del Caudillo aprovecha este contexto para desarrollar una intensa propaganda en el Río de la Plata. Para llevar a cabo las distintas acciones propagandísticas, los representantes españoles en Argentina tendrán que luchar contra las actividades antifranquistas de los exiliados.The end of World War II and the international condemnation of Spain put Franco’s regime in a very delicate situation. However, the Argentinian government of the general Peron appeared as a “life jacket” for the Spanish dictatorship. The government of the Caudillo used this context to develop a very intense propaganda in the Rio de la Plata. Still, to conclude their various propagandist actions, the Spanish representatives in Argentina had to fight against the activities of antifranquist people in exile.
Ceballos, L A; Piccinali, R V; Berkunsky, I; Kitron, U; Gürtler, R E
Triatoma infestans (Klug), the most important vector of Chagas disease in southern South America, is a highly domiciliated species with well-known sylvatic foci only in the Bolivian Andean valleys and in the Bolivian Chaco, where melanic insects designated as "dark morphs" were found. After the tentative identification of two melanic bugs collected from parrot nests in a forest reserve in the Argentine Chaco as T. infestans, we conducted an intensive search there using mouse-baited sticky traps in summer 2006 and 2007. Four live T. infestans bugs were collected in trees without parrot nests in 288 trap-nights, whereas no bug was collected from inside trees with active parrot nests in 51 trap-nights. To increase bug captures, hollow tree trunks that recently had had Amazona aestiva (Berlepsch) and Aratinga acuticaudata (Vieillot) parrot nests were treated with insecticide fumigant canisters exhibiting strong knockdown power. Four (22%) of 18 trees were positive for T. infestans with a dark phenotype. A fragment of the mitochondrial gene COI of 8 of the 14 triatomine bugs collected was successfully sequenced and confirmed as T. infestans. Most of the bugs were captured from Aspidosperma quebracho-blanco (Schlechter) hollow tree trunks harboring parrot nests. All of the T. infestans collected from the nearest house located at 10 km from the sylvatic foci displayed normal chromatic characters. The repeated finding of T. infestans in sylvatic habitats, albeit at very low density, shows that this species is capable of maintaining viable sylvatic foci in the absence of human hosts and immigration from domestic populations. These are the first confirmed findings of sylvatic T. infestans colonies in Argentina and of dark morphs in the Argentine Chaco. PMID:19769054
CEBALLOS, L. A.; PICCINALI, R. V.; BERKUNSKY, I.; KITRON, U.; GÜRTLER, R. E.
Triatoma infestans (Klug), the most important vector of Chagas disease in southern South America, is a highly domiciliated species with well-known sylvatic foci only in the Bolivian Andean valleys and in the Bolivian Chaco, where melanic insects designated as “dark morphs” were found. After the tentative identification of two melanic bugs collected from parrot nests in a forest reserve in the Argentine Chaco as T. infestans, we conducted an intensive search there using mouse-baited sticky traps in summer 2006 and 2007. Four live T. infestans bugs were collected in trees without parrot nests in 288 trap-nights, whereas no bug was collected from inside trees with active parrot nests in 51 trap-nights. To increase bug captures, hollow tree trunks that recently had had Amazona aestiva (Berlepsch) and Aratinga acuticaudata (Vieillot) parrot nests were treated with insecticide fumigant canisters exhibiting strong knockdown power. Four (22%) of 18 trees were positive for T. infestans with a dark phenotype. A fragment of the mitochondrial gene COI of 8 of the 14 triatomine bugs collected was successfully sequenced and confirmed as T. infestans. Most of the bugs were captured from Aspidosperma quebracho-blanco (Schlechter) hollow tree trunks harboring parrot nests. All of the T. infestans collected from the nearest house located at 10 km from the sylvatic foci displayed normal chromatic characters. The repeated finding of T. infestans in sylvatic habitats, albeit at very low density, shows that this species is capable of maintaining viable sylvatic foci in the absence of human hosts and immigration from domestic populations. These are the first confirmed findings of sylvatic T. infestans colonies in Argentina and of dark morphs in the Argentine Chaco. PMID:19769054
Alemany, Daniela; Acha, Eduardo M.; Iribarne, Oscar O.
The high primary and secondary production associated with frontal systems attract a diversity of organisms due to high prey availability; this is why a strong relationship between fronts and pelagic fisheries has been shown worldwide. In the Argentine Sea, demersal resources are the most important, both in economical and in ecological sense; so we hypothesize that fronts are also preferred fishing areas for demersal resources. We evaluated the relationship between spatial distribution of fishing effort and oceanographic fronts, analyzing three of the most important frontal systems located in the Argentine Sea: the shelf-break front, the southern Patagonia front and the mid-shelf front. Individual vessel satellite monitoring system data (VMS; grouped by fleet type: ice-trawlers, freezer-trawlers and jigging fleet) were studied and fishing events were identified. Fishing events per area were used as a proxy of fishing effort and its spatial distribution by fleet type was visualized and analyzed with Geographic Information Systems. Oceanographic fronts were defined using polygons based on satellite chlorophyll amplitude values, and the percentage of fishing events within each polygon was calculated. Results showed a positive association between fronts and fishing activities of the different fleets, which suggests the aggregation of target species in these zones. The coupling of the freezer-trawler and jigging fleets (that operate on lower trophic level species; Macruronus magellanicus and Illex argentinus respectively) with fronts was higher than the ice-trawler fleet, targeting species of higher trophic level (Merluccius hubbsi). Marine fronts represent important fishing areas, even for demersal resources, as the distribution of fishing fleets and fishing effort are positively associated with frontal zones.
This economical study summarizes the energy situation of Argentina: energy institutions and policy, energy companies (oil, electricity, gas, coal), energy supplies (resources, power production, petroleum, natural gas), prices and tariffs, consumption, economical stakes and perspectives (investments, agreements, projects). Energy data for the 1971-1999 period are summarized in graphs and tables. (J.S.)
The Argentine Atomic Energy Commission started in 1978 the Reduced Enrichment Research and Test Reactors in the field of reactor engineering; engineering, development and manufacturing of fuel elements and research reactors operators. This program was initiated with the conviction that it would contribute to the international efforts to reduce risks of nuclear weapons proliferation owing to an uncontrolled use of highly enriched uranium. It was intended to convert RA-3 reactor to make possible its operation with low enriched fuel (LEU), instead of high enriched fuel (HEU) and to develop manufacturing techniques for said LEU. Afterwards, this program was adapted to assist other countries in reactors conversion, development of the corresponding fuel elements and supply of fuel elements to other countries. (Author)
Ce texte est un extrait du quatrième chapitre de la thèse « Néstor Kirchner (2003-2007) : Rupture ou continuité du péronisme. Les mutations du populisme en Argentine ». Le 25 mai 2003, le peuple argentin assistait à l’investiture présidentielle du candidat du Frente Para la Victoria, Néstor Kirchner. Suite à la défection de Carlos Menem pendant l’entre-deux tours, il est élu avec 22% des suffrages. Malgré cette faible légitimité, il réussit à insuffler un changement certain dans la politique ...
Gerald A. McDermott; Rafael A Corredoira
What types of relational and institutional mechanisms shape knowledge flows and the upgrading capabilities of emerging-market firms in the face of economic liberalization? We analyze the Argentine autoparts sector to distinguish the relative impact of different types of network relationships on a firm's process and product upgrading. A few social ties to international assemblers appear to be most beneficial for local suppliers, although they may be insufficient to compensate fully for the neg...
Barrett, Eoin George
This cultural history of Argentine crime fiction involves a comprehensive analysis of the literary and critical traditions within the genre, paying particular attention to the series of ‘aesthetic campaigns’ waged by Jorge Luis Borges and others during the period between 1933 and 1977. The methodological approach described in the introductory chapter builds upon the critical insight that in Argentina, generic discourse has consistently been the domain, not only of literary critics in the trad...
This thesis aims to elaborate a case study of self-managed factories, which has been emerging in Argentina after the economic crisis in 2001. Mainly the conflictive origin, organization, role of the state and the dynamics of the movement of self-managed factories is discussed. This paper is based on European tradition of social movements' analysis and seeks to characterize movement of Argentine self-managed factories as so called old or new social movement. This dividing line will ultimately ...
Edwards-Schachter, Mónica; Anlló, Guillermo; Castro-Martínez, Elena; Sánchez-Barrioluengo, Mabel; Fernández de Lucio, Ignacio
Motives and determinants supporting inter-firm technological cooperation have been extensively investigated in developed countries but scarcely addressed in developing countries. This paper addresses these issues, investigating empirically several factors influencing the likelihood to cooperate on R&D and innovation between Argentine and Spanish firms, their strategic motives and firms characteristics which influence cooperation. We draw upon data collected through a survey of 104 firms and c...
Carballal, G; Oubiña, J. R.; Rondinone, S N; Elsner, B; Frigerio, M J
Guinea pigs infected with the XJ prototype strain of Junín virus reproduce the main features of Argentine hemorrhagic fever, showing hemorrhages, leukothrombocytopenia, and focal lymphoid tissue necrosis. Viral lymphotropism is shown by the presence of viral antigens, severe cytopathic effect, and high virus titers in lymphoid organs. A pronounced depression of humoral immune response to sheep erythrocytes as well as to the virus is described. This study was carried out to determine whether c...
The document reproduces the text of a letter dated 31 March 2000 from the Resident Representative of the Argentine Republic, including as attachment the declaration of the Advisory and Political Harmonisation Forum of MERCOSUR (Argentina, Brazil, Paraguay, Uruguay), Bolivia and Chile, issued on 27 March 2000, with regard to the 30th Anniversary of the entry into force of the Treaty on the Non-Proliferation of Nuclear Weapons
Internationalization is not a simple decision but rather a complex strategy that requires the presence of tangible and intangible resources that, in the case of a family firm, call for careful analysis. To understand this process, the present study reconstructs the historical trajectories of two important Argentine laboratories, Bagó and Sidus, in historical perspective, using the stage approach of the Uppsala school (U-model) and the perspective of resources and capacities (resource-based vi...
Gruetzner, Jens; Uenzelmann-Neben, Gabriele; Franke, Dieter; Arndt, Jan Erik
Geochemical evidence from boreholes suggests enhanced transport of Northern Component Water (NCW) to southern latitudes from about 6 Ma onwards. However, information on how this change in transport influenced the intensity and position of current systems is sparse. Here we use seismic reflection profiles interpreted together with bathymetric data to investigate current derived deposits at the central Argentine Margin. Upslope migrating mudwaves overlying a late Miocene erosional unconformity ...
LeVan, Katherine E; Hung, Keng-Lou James; McCann, Kyle R; Ludka, John T; Holway, David A
Mounting evidence indicates that trade-offs between plant defense and reproduction arise not only from resource allocation but also from interactions among mutualists. Indirect costs of plant defense by ants, for example, can outweigh benefits if ants deter pollinators. Plants can dissuade ants from occupying flowers, but such arrangements may break down when novel ant partners infiltrate mutualisms. Here, we examine how floral visitation by ants affects pollination services when the invasive Argentine ant (Linepithema humile) replaces a native ant species in a food-for-protection mutualism with the coast barrel cactus (Ferocactus viridescens), which, like certain other barrel cacti, produces extrafloral nectar. We compared the effects of floral visitation by the Argentine ant with those of the most prevalent native ant species (Crematogaster californica). Compared to C. californica, the Argentine ant was present in higher numbers in flowers. Cactus bees (Diadasia spp.), the key pollinators in this system, spent less time in flowers when cacti were occupied by the Argentine ant compared to when cacti were occupied by C. californica. Presumably as a consequence of decreased duration of floral visits by Diadasia, cacti occupied by L. humile set fewer seeds per fruit and produced fewer seeds overall compared to cacti occupied by C. californica. These data illustrate the importance of mutualist identity in cases where plants balance multiple mutualisms. Moreover, as habitats become increasingly infiltrated by introduced species, the loss of native mutualists and their replacement by non-native species may alter the shape of trade-offs between plant defense and reproduction. PMID:23892582
Grau Olive, Juan Bautista; Antón Corrales, José Manuel; Cisneros, J.M.; Andina de la Fuente, Diego; Tarquis Alfonso, Ana Maria; Prada, M.; A. Degioanni; Cantero, A.
The erosion-sedimentation-flooding processes in large zones of Argentine are a critical problem that involve complex relationships with technological, economic, social and environmental cause-effect. The increasing of agricultural activities in new areas previously with forestry or pasture could produce irreversible environmental impacts. It is necessary to prepare a spatial plan taking into consideration, economic development, social cohesion, environmental quality and progressive desertific...
This paper proposes to analyze the “woman question” in relation to tropes of schizophrenia in post-dictatorial queer Argentine fiction. Gilles Deleuze and Felix Guttari’s claim in Anti-Oedipus: Capitalism and Schizophrenia states: “schizoanalysis must devote itself with all its strength to the necessary destructions….. Destroying beliefs and representations, theatrical scenes. And when engaged in this task no activity will be too malevolent.” Similarly, Manuel Puig’s El Beso de la mujer ...
Mathieson, Melissa; Toft, Richard; Lester, Philip J
The efficacy of toxic baits should be judged by their ability to kill entire ant colonies, including the colony queen or queens. We studied the efficacy of four toxic baits to the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae). These baits were Xstinguish that has the toxicant fipronil, Exterm-an-Ant that contains both boric acid and sodium borate, and Advion ant gel and Advion ant bait arena that both have indoxacarb. Experimental nests contained 300 workers and 10 queen ants that were starved for either 24 or 48 h before toxic bait exposure. The efficacy of the toxic baits was strongly influenced by starvation. In no treatment with 24-h starvation did we observe 100% worker death. After 24-h starvation three of the baits did not result in any queen deaths, with only Exterm-an-Ant producing an average of 25% mortality. In contrast, 100% queen and worker mortality was observed in colonies starved for 48 h and given Xstinguish or Exterm-an-Ant. The baits Advion ant gel and Advion ant bait arena were not effective against Argentine ants in these trials, resulting in bait uptake, control efficacy may be maximized by applying bait when ants are likely to be starved. Our results suggest queen mortality must be assessed in tests for toxic bait efficacy. Our data indicate that of these four baits, Xstinguish and Exterm-an-Ant are the best options for control of Argentine ants in New Zealand. PMID:22928290
The regimes of accountability, the organizations of global governance and institutional arrangements of global governance of nuclear non-proliferation and of Mutual Vigilance Brazilian-Argentine of Nuclear Safeguards are the subject of research. The starting point is the importance of the institutional model of global governance for the effective control of non-proliferation of nuclear weapons. In this context, the research investigates how to structure the current arrangements of the international nuclear non-proliferation and what is the performance of model Mutual Vigilance Brazilian-Argentine of Nuclear Safeguards in relation to accountability regimes of global governance. For that, was searched the current literature of three theoretical dimensions: accountability, global governance and global governance organizations. In relation to the research method was used the case study and the treatment technique of data the analysis of content. The results allowed: to establish an evaluation model based on accountability mechanisms; to assess how behaves the model Mutual Vigilance Brazilian-Argentine Nuclear Safeguards front of the proposed accountability regime; and to measure the degree to which regional arrangements that work with systems of global governance can strengthen these international systems. (author)
Federal Laboratory Consortium — The last of Hanfordqaodmasdkwaspemas7ajkqlsmdqpakldnzsdflss nine plutonium production reactors to be built was the N Reactor.This reactor was called a dual purpose...
The Argentine RA-3 research reactor (5 MW) is presently operated with LEU fuel by the National Atomic Energy Commission (CNEA). It belongs to the group of nuclear installations controlled, from the radiological and nuclear safety point of view, by the Nuclear Regulatory Authority (ARN). A new type of fuel elements containing burnable absorbers, with similar enrichment as the standard fuel elements but greater fissile contents, has recently been proposed for a new Argentine reactor design (RRR). In this framework the ARN considers interesting, if technically possible, the performance of an experiment in the RA-3 reactor. The experiment might enable, for such fuel element containing burnable poison, the verification of its neutronic behaviour under irradiation as well as a validation of the calculation line by comparison to measured values. It should be desirable that such experiment could reproduce as much as possible those conditions estimated for the RRR reactor, still under design in Argentina, having Silicide fuel elements with burnable poison, in the shape of cadmium wires in their structure. We here analyse a possible experiment consisting in the loading of a prototype fuel element with burnable poison in a normally loaded RA-3 core configuration. It would essentially be a standard RA-3 fuel element, having cadmium wires in its frame. This experiment would enable the verification of the prototype behaviour under irradiation, its operation limits and conditions, and particularly, the reactivity safety margins established in Argentine Standards, both calculated and measured. The main part of the experiment would imply some 200 full power days of operation at 5 MW, which would be drastically reduced if the reactor power is increased to 10 MW, as foreseen. We also show that under the proposed conditions, the experiment would not represent a significant penalty to the reactor normal operation. (author)
'American foulbrood' is a disease that seriously affects bees. Honey may be contaminated with spores of the related bacteria, Paenibacillus larvae larvae, which is a great drawback for trade. The scientific literature reports that these spores, resistant to heat and chemicals, are inactivated in honey when it is irradiated al 10 kGy, being this treatment mandatory in the Republic of Southafrica. Irradiated food wholesomeness is endorsed by the World Health Organization. Considering that Argentina is an important honey producer and exporter, the aim of this work was to evaluate the effect of ionizing radiation on some of its commercial chemical parameters along storage time. Honeys with different characteristics, coming from five different regions of the country: Middle, Patagonia, North, Litoral, Humid Pampa, were provided by producers from a commission called 'Packaged honey' of the National Food, Fishery and Agriculture Ministry. Fifteen kg of each honey variety were packaged in 500 g polypropylene recipes with polyethylene lids, and irradiated at the semi industrial cobalt-60 facility of the Ezeiza Atomic Center, 500,000 Ci of activity, with doses of 0, 10 and 20 kilo Grays. Control and irradiated samples were stored at room temperature for 10 months. Some standardized chemical analysis required by the Argentine Food Code (AFC) were performed on the first, fourth and tenth storage months: water content, acidity, diastase content, reducing sugars, and hydroxymethylfurfural. Reducing sugars and diastase activity slightly diminished, and acidity slightly increased, along storage which is typical in this product; no significant differences were found between control and irradiated samples. Hydroxymethylfurfural values, related to aging or thermal abuse, diminished slightly though significantly due to irradiation, which would not affect the product quality as regulations require not to surpass a maximum value, 40 mg/kg in the AFC. So ionizing
Edward C. Epstein
Full Text Available This article examines the recent behaviour in Argentina of two national protest groups of socalled ‘piqueteros’ or picketers (impoverished unemployed individuals who used the blockage of strategic roads and bridges to force government concessions that emerged politically in the buildup to the crisis of 2001-2002. Using theoretical concepts developed by McAdam, Tarrow, and Tilly in understanding social movements, the author analyses what he calls the ‘survival strategy’ adopted by their leaders as the political opportunities that produced their initial growth gave way to a more hostile environment with the normalization of Argentine politics under the Kirchner administration. While the two piquetero groups studied differ considerably in terms of their politics and ideology, both ended up depending on the same traditional tactic of utilizing important government contacts to obtain the resources necessary for organizational maintenance, despite their nominal identity as radical protesters against the present political system.Resumen: Perpetuando movimientos sociales y oportunidades decrecientes: las estrategias de sobrevivencia de dos grupos de piqueteros argentinesEste artículo examina el comportamiento reciente de dos grupos nacionales de protesta argentinos llamados ‘piqueteros’ (desempleados empobrecidos que usaron el bloqueo de calles y puentes estratégicos para forzar concesiones gubernamentales que aparecieron durante la crisis de 2001- 2002. Utilizando conceptos teóricos creados por McAdam, Tarrow, y Tilly en su discusión sobre los movimientos sociales, el autor analiza lo que describe como ‘estrategias de sobrevivencia’ adoptadas por sus dirigentes cuando las oportunidades que ocasionaron su crecimiento inicial cedieron ante un ambiente más hostil en el contexto de la normalización de la política argentina durante la administración de Kirchner. Aunque los dos grupos piqueteros estudiados se diferencian mucho en t
A. Lo Vecchio
Full Text Available The object of this study aims to evaluate and analyze digital image processing techniques applied to the Enhanced Thematic Mapper Plus (ETM+, in order to demark and characterize the outcropping lithologies on the Upsala Glacier basin, Santa Cruz, Argentine Republic. The prolific technological and spatial development experienced in the last decades has given place to the generation, without precedents, of multiple remote sensors capable of capturing information of the terrestrial surface and also the improvement of digital image processing techniques and software; amongst them, the amazing possibilities in the detection and differentiation of diverse covers present on the terrestrial surface can be highlighted, such as glaciers, volcanoes, vegetation, soils, water, types of rock outcrops, etc. This situation improves mapping and monitoring of natural phenomenon in the Earth Sciences field. The proposed methodology includes radiometric corrections, elimination of unwanted covers, statistical evaluation in the combination of the most appropriate bands, application of the Z index, discretization of the statistical series, entailing tasks of spectral classification with field samples and a later validation. Valuable results were obtained by means of digital processing of images, that were validated yielding a 82% of accuracy in the proposed classification, which are good results taking into account the diversity of covers present and the lithological heterogeneity that makes up each pixel (30m. These results were also validated with existing geological maps, obtaining a good agreement.
Greenberg, L; Klotz, J H
We investigated whether the Argentine ant, Linepithema humile (Mayr), trail pheromone, Z9-16:Ald, could enhance recruitment to and consumption of liquid sucrose solutions. All tests were done as paired comparisons with a 10% sucrose solution as food. In the laboratory, mixing 20 microl of a 10-microg/ml solution of the pheromone with 50 microl of the 10% sucrose solution increased the number of ants feeding by >150%. In a field test, we combined the trail pheromone with a 10% sucrose solution in 50-ml vials. These vials were covered with a plastic membrane that has 1.5-mm-diameter holes punched uniformly across its surface. Ants could drink from the holes after the vials were inverted. For half of the vials, 1 microg of the pheromone was put onto the plastic membrane before the vials were filled with a 10% sucrose solution. The remaining vials had no pheromone on the plastic membrane. After 4 h we measured the consumption in each vial. Bait consumption with the pheromone was enhanced by 29%. In a 2nd series of tests, vials were left outside for 24 h. The consumption rate was 33% higher with the pheromone compared with the controls that didn't have pheromone. PMID:14658521
María Gabriela Merín
Full Text Available Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL. This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce β-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking.
Merín, María Gabriela; Martín, María Carolina; Rantsiou, Kalliopi; Cocolin, Luca; de Ambrosini, Vilma Inés Morata
Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL). This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce β-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking. PMID:26413065
Teaching and the training are indispensable for the development of the human resources in all disciplines and occupations of the man in the world scale. About the applications of the radionuclides in the nuclear industry, in Argentina, during the last years, the efforts have been intensified. The necessity of improving the capacity of answer in radiation protection and nuclear safety demands an focus integrated in the teaching and the training. The radiological protection and the nuclear safety presents elements of the applied physics, the chemistry, the biology, the nuclear technology and other specialized subjects. However, in relation with the development of the human resources, specially those that belong to regulatory bodies and perform inspection functions, have important differences, necessities and specific problems. Some differences and problems emerge of the wide diversity and reach of the radiological and nuclear applications. Nowadays, in the world, the applications of the radiation and radioactive sources are being diversified in the medicine (diagnosis, radiotherapy, nuclear medicine, the industry, the agricultures, and the investigation and teaching), that involve a permanent knowledge and actualization of the personnel of the regulatory bodies. For that exposed this work describe training program for the personnel with regulatory functions (inspectors) of the Nuclear Regulatory Authority in the Argentine Republic. Also, this document includes the description of the basic formation and specialized in each case and it reach. (author)
Argentina has given recently a new start to its nuclear power activities. Looking for background and experiences that can be useful under the new reality, the paper is a survey of the past development of local suppliers for the national nuclear industry. Based on the intention to answer the questions: Why so early it was decided to build a nuclear power plant? Why it was decided to buy it under a turnkey basis rather than developing an indigenous design? and what was the meaning of the 'opening of the technology package' at that time?, the paper describes the actions that led to the purchase of the Atucha I, Embalse and Atucha II nuclear power plants and how these decisions were implemented in order to maximize local participation and the technology transfer. It also analyzes the influence of the Argentine Nuclear Plan of the late seventies on the development of endogenous technology and describes the facts that helped to preserve until now the technological nuclear capabilities of the country in spite of the stopping of the Atucha II construction, and to create positive expectations regarding the revival of the local industry as a supplier of nuclear goods and services. (author)
Full Text Available El gobierno argentino del general Perón reveló ser un verdadero chaleco salvavidas para la dictadura española. Esta política de cooperación provoca una viva oposición en Argentina. Este trabajo propone un análisis de las reacciones de los intelectuales españoles exiliados en Argentina. Observaremos de que manera los intelectuales españoles lucharon contra la dictadura franquista durante el idilio hispano-argentino y analizaremos el “modus operandi” adoptado por el gobierno peronista para obstaculizar las actividades anti-franquistas en el exilio.__________________ABSTRACT:The Argentine government of general Perón becomes an authentic life jacket for the Spanish dictatorship. This policy of cooperation triggers ample dispproval in Argentina. We propose an analysis of the reactions of the spanish intellectuals exiled in Argentina. We will see how the Spanish intellectuals fight against the Franco dictatorship during the honeymoon Hispanic-Argentinean. Also we will analyze the modus operandi adopted by the Peronist government to prevent the antifrancoist activities of the exiliados.
One of the main aims in the study of the complexes of humic substances and plant mineral nutrients in the soil is to obtain thermodynamic data which, compared with known systems, can give the necessary information to calculate the element activity in solution. This information is essential for predicting the dynamics of such nutrients in the soil solution, since the latter is one of the main locations of fundamental reactions related to soil genesis and fertility. The distribution of radioactive 65Zn and non-radioactive Cu between a cation exchange resin and the humic systems was used to calculate the stability constants of these elements and the humic acids (HA) extracted from various Argentine soils. On the basis of these stability constants, the following conclusions were obtained: (1) Copper was more strongly complexed than zinc by the humic acid of a Solod soil. Copper had also almost the same value of the logarithm of the stability constant for several soils (8.1 to 9.1); (2) The value of the stability constant of the Zn-HA complex was higher for a Chestnut soil (Petrocalcic Paleustoll) than for the other soils studied; (3) Since HA is an important insoluble fraction in normal soil conditions, it is suggested that the mobility of Cu is low in the soil solution of these soils. Therefore, a Cu deficiency may be predicted or expected. (author)
Full Text Available Infestations of buildings by Argentine ants, Linepithema humile (Mayr, were monitored on the campus of the University of California, Los Angeles. Foraging ant activity peaked during the hotter months of the year. The mean monthly maximum temperature, but not rainfall, positively correlated with indoor infestation frequency. Neither garden size nor the predominant groundcover vegetation correlated with the number of foraging ants at baits within gardens. Although the number of foraging ants outside a building varied over 40-fold, ant density in gardens did not predict the likelihood of infestation within the building. Also, the type of vegetative groundcover employed did not predict infestation frequency. There was, however, a significant negative relationship between the size of the garden outside of a building and the number of infestations. Given the large foraging area of L. humile workers, buildings next to small gardens may be infested simply because they lie within the “normal” foraging area of a colony. The best predictor of which rooms were infested within buildings was the presence of a water source. Thus providing water for ant colonies outside and away from buildings may be one method of integrated pest management to reduce the proclivity of ants to infest structures.
Felipe M Carvalho
Full Text Available The Argentine anchovy (Engraulis anchoita is an essential species in the pelagic ecosystem of the southwest Atlantic Ocean, and a potentially important fishery resource. Exploitation has recently started in southern Brazil, so it requires a better understanding of their structure and population dynamics. This work aims to update the information on the population identification of E. anchoita. Parameters such as age and size composition, length-at-age data and other parameters using sagittae otoliths were used to compare anchovy of the continental shelf between 20° and 32°S. The results indicate the existence of different populations in the southeastern and southern regions of Brazil: the bonaerense stock in southern Brazil is shared with Argentina and Uruguay and exhibits migratory behavior, while in the southeast there is a population confined to this region and shows different population characteristics. This has implications for the management of this species and should be taken into account by the institutions responsible for the assessment and management of fisheries in Brazil.
A. D. Danilov
Full Text Available The ionospheric sounding data at two southern hemisphere stations, the Argentine Islands and Port Stanley, are analyzed using a method previously developed by the authors. Negative trends of the critical frequency foF2 are found for both stations. The magnitudes of the trends are close to those at the corresponding (close geomagnetic latitude stations of the northern hemisphere, as considered previously by the authors. The values of the F2 layer height hmF2 absolute trends ΔhmF2 are considered. The effect of ΔhmF2 dependence on hmF2 found by Jarvis et al. (1998 is reproduced. A concept is considered that long-term changes of the geomagnetic activity may be an important (if not the only cause of all the trends of foF2 and hmF2 derived by several groups of authors. The dependence of both parameters on the geomagnetic index Ap corresponds to a smooth scheme of the ionospheric storm physics and morphology; thus, a principal cause of the foF2 and hmF2 geomagnetic trends is most probably a trend found in several publications in the number and intensity of ionospheric storms.
Key words. Ionosphere (ionosphere-atmosphere interaction; ionospheric disturbances
This paper is a review of the current status about the remaining problems that are found in the investigation of the Quaternary Argentine soils and loessic sediments, and the way that Moessbauer studies can assist in solving them. There are two main types of investigations that make use of the magnetic response of the samples to correlate them with information gathered by other methods. On the one hand, there is the stratigraphic and chronological research, which is of importance from the geological and paleontological points of view. On the other hand, the paleoclimatic records, of significance toward a possible model of the past climate, are also studied because of their close relation to the sediments history. However, there is not yet a model that can tell the difference between the modifications due to the climatic conditions at the time when the soils were buried from processes that occurred after burial. Some examples are given that show that Moessbauer studies can be applied with a certain degree of success when cross-checked with magnetic measurements toward understanding the processes that occurred in alluvial B (paleosols) and C horizons (loess) from the eastern part of Buenos Aires Province. Although the application of Moessbauer studies to hydromorphic processes in soils is not straightforward, there are cases in which Moessbauer spectroscopy, if applied properly and correlated with other techniques, is able to characterize the type of iron oxides existing in the materials and thus assist theories about its origin and history.
The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised
SCK-CEN's Reactor Physics and MYRRHA Department offers expertise in various areas of reactor physics, in particular in neutron and gamma calculations, reactor dosimetry, reactor operation and control, reactor code benchmarking and reactor safety calculations. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 materials testing reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2001 are summarised
Ait Abderrahim, A
The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.
Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp
Russell, Charles R
Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor
The present work pretends to evaluate the benefits that may be obtained from changing the natural uranium cycle that is presently used instead of that of Pu spiking which consists in changing a few elements with mixed oxides fuel with the plutonium reprocessed from all the fuel elements on the periphery of the reactor, maintaining the actual reactor's operating conditions. (Author)
CAREM-25 is an Argentine project to achieve the development, design, and construction of an innovative simple and small NPP, which is jointly developed by CNEA (National Atomic Energy Commission) and INVAP. This nuclear plant has an indirect cycle reactor with some distinctive and characteristic features that greatly simplify the design, and contributes to a higher safety level. Some of the high level design characteristics of the plant are: integrated primary cooling system, self-pressurized primary system and safety systems relying on passive features
Tirage 1:President of the Argentine Nation, C. Fernández and Minister of Science, Technology and Innovative Production,L. Barañao Tirage 2-8:Arrival greetings Tirage 9-12:Introduction to CERN's activities by Director-General, R. Heuer Tirage 13-15:Signature of the guest book Tirage 16-25:M. Benedetti,R. Heuer and L.Barañao sit for the signature of the Agreement Tirage 26-33: Meeting with Argentinian scientists at CERN
Ushuaia et Punta Arenas sont les villes les plus australes de leurs pays d’appartenance, l’Argentine et le Chili. Elles ont joué le rôle de ville frontière au service de la consolidation et la légitimation de ces territoires nationaux austraux localisés en position de bout du monde. Depuis cinquante ans, ces deux villes portuaires s’affirment comme les deux portes d’entrée internationales principales des relations avec le continent Antarctique, et en particulier avec la Péninsule Antarctique...
L'Argentine a mené entre 1991 et 2001 une des expériences de currency board les plus remarquables de la période moderne. Comment rendre compte de cette expérience, prise dans son ensemble ? Qu'apprend-elle sur les avantages et les inconvénients des currency board ? Comment expliquer son échec final et quelles conclusions plus générales en tirer ? Telles sont les questions auxquelles cet article souhaite apporter des éléments de réponse. Pour cela, l'auteur commence par rappeler les principaux...
Full Text Available Abstract Background The occurrence of variations in the spectrum of cardiovascular disease between different regions of the world and ethnic groups have been the subject of great interest. This study report the 24-h variation of myocardial infarction (MI occurrence in patients recruited from CCU located in Argentina and Uruguay. Methods A cohort of 1063 patients admitted to the CCU within 24 h of the onset of symptoms of an acute MI was examined. MI incidence along the day was computed in 1 h-intervals. Results A minimal MI incidence between 03:00 and 07:00 h and the occurrence of a first maximum between 08:00 and 12:00 h and a second maximum between 15:00 and 22:00 h were verified. The best fit curve was a 24 h cosinor (acrophase ~ 19:00 h, accounting for 63 % of variance together with a symmetrical gaussian bell (maximum at ~ 10:00 h, accounting for 37 % of variance. A similar picture was observed for MI frequencies among different excluding subgroups (older or younger than 70 years; with or without previous symptoms; diabetics or non diabetics; Q wave- or non-Q wave-type MI; anterior or inferior MI location. Proportion between cosinor and gaussian probabilities was maintained among most subgroups except for older patients who had more MI at the afternoon and patients with previous symptoms who were equally distributed among the morning and afternoon maxima. Conclusion The results support the existence of two maxima (at morning and afternoon hours in MI incidence in the Argentine and Uruguayan population.
Gruetzner, Jens; Uenzelmann-Neben, Gabriele; Franke, Dieter
The construction of the sedimentary cover at most passive continental margins includes gravitational downslope transport and along-slope contourite deposition, which are controlled by tectonics, climate and oceanography. At the eastern continental margin of Argentina the history of deposition and erosion is intimately linked to the evolution of the South Atlantic and its water masses. Here we present a detailed seismic investigation of the mixed depositional system located between 41°S and 45°S. The study provides a northward complement to prior investigations from the southern Argentine margin and together with these may be used as background information for future ocean drilling in the region. Prominent features in our seismic cross sections are submarine canyons, mass wasting deposits, contourite channels, and sediment drifts. Four major seismic units above regional reflector PLe (˜65 Ma) are separated by distinct unconformities of regional extent. Using a dense grid of reflection seismic profiles, we mapped the depocenter geometries of the seismic units and derived a chronology of the depositional processes during the Cenozoic. While the Paleocene/Eocene (˜65-34 Ma) is characterized by hemipelagic sedimentation under relatively sluggish bottom water conditions, strong Antarctic bottom water (AABW) circulation led to widespread erosion on the slope and growth of a detached sediment drift during the Oligocene and early Miocene (˜34-17 Ma). After deposition of an aggradational seismic unit interpreted to represent the Mid-Miocene climatic optimum (˜17-14 Ma), gravitational downslope sediment transport increased during the middle to late Miocene (˜14-6 Ma) possibly related to tectonic uplift in South America. The Pliocene to Holocene unit (<˜6 Ma) is very heterogeneous and formed by interactions of downslope and along-slope sediment transport processes as indicated by the evolution of canyons, slope plastered drifts and channels.
Full Text Available Practices of other-initiated repair deal with problems of hearing or understanding what another person has said in the fast-moving turn-by-turn flow of conversation. As such, other-initiated repair plays a fundamental role in the maintenance of intersubjectivity in social interaction. This study finds and analyses a special type of other-initiated repair that is used in turn-by-turn conversation in a sign language: Argentine Sign Language (Lengua de Señas Argentina or LSA. We describe a type of response termed a ‘freeze-look’, which occurs when a person has just been asked a direct question: instead of answering the question in the next turn position, the person holds still while looking directly at the questioner. In these cases it is clear that the person is aware of having just been addressed and is not otherwise accounting for their delay in responding (e.g., by displaying a ‘thinking’ face or hesitation, etc.. We find that this behavior functions as a way for an addressee to initiate repair by the person who asked the question. The ‘freeze-look’ results in the questioner ‘re-doing’ their action of asking a question, for example by repeating or rephrasing it. Thus we argue that the ‘freeze-look’ is a practice for other-initiation of repair. In addition, we argue that it is an ‘off-record’ practice, thus contrasting with known on-record practices such as saying ‘Huh?’ or equivalents. The findings aim to contribute to research on human understanding in everyday turn-by-turn conversation by looking at an understudied sign language, with possible implications for our understanding of visual bodily communication in spoken languages as well.
Seipt, E. C.; Easterling, W. E.
A distinct El Niño - Southern Oscillation (ENSO) signal and its impacts have been confirmed in the Argentine Pampas, and precipitation variability is currently recognized as the region's most marked ENSO-driven influence. In the Pampas, precipitation is also a major limiting factor for agricultural production given spatial differences in soil water storage capacities and the region's relatively minimal use of irrigation. Seasonal climate forecasts that provide advanced knowledge of expected ENSO-driven precipitation anomalies may benefit farm management decision-making by helping to either mitigate potentially negative consequences or to take advantage of potentially positive influences. To be useful and applicable, however, these forecasts must suit the decisions that they are meant to inform. In this research, a case study is presented that investigates how farmers in the Pampas prioritize and trade off specific attributes of a seasonal climate forecast (i.e., mode of distribution, spatial resolution, lead time, and forecast performance) when judging its utility. A conjoint analysis evaluation decomposes holistic evaluations of forecasts into the part-worth utilities associated with their different attributes. Part-worth utilities combine to reveal the structure of farmers' forecast utility preferences - a model of the decision-making process. Utility preference structures are analyzed to compute the importance value of each attribute and to determine the trade-offs that farmers find acceptable between different attributes. Analysis indicates that, on average, spatial resolution is the most influential attribute in determining climate forecast utility. Attribute trade-off values suggest that advances in spatial resolution, forecast performance, and/or product dissemination via the Internet offer the greatest potential for increasing the utility of future seasonal climate forecasts for farmers in the Pampas.
In the framework of the Argentine Boron Neutron Capture Therapy (BNCT) project for treating metastatic cutaneous melanoma, we have initiated a research and development program aimed at obtaining a noninvasive methodology for following-up the treated patients. The technique is called Dynamic Infrared Imaging (DIRI) and comprises the acquisition of infrared images as a function of time of the anatomical part under study, when the region is subjected to a mild cold stress. Vascular, metabolic and regulating differences between normal and tumor tissues appear as differences in the pattern of temperature evolution, which can be correlated with the anatomical and functional aspects of both. Two patients enrolled in the BNCT protocol were studied with DIRI. A good spatial correlation between dose, temperature recovery velocity and skin reaction distributions was observed at the time of maximum expression of the erythematous reaction. Melanoma nodules appear as highly localized hyperthermic regions, surrounded and interconnected by elevated temperature areas. Their temperature recovery velocity after the thermal cold stress was substantially faster than that of normal skin with an appreciably large temperature difference (6 degreesC to 10 degreesC). These tissue differences can be related with the thermal conductivity and metabolic rate as explained by a simple one-directional heat transport model. Compared with other imaging modalities (CT and Doppler ultrasound) DIRI has had a similar ability for confirming the already diagnosed nodules. Together with the clinical observation, DIRI provides a potentially useful amount of information, at a competitive cost-benefit relationship suitable for performing a non-invasive functional assessment of this kind of cutaneous lesions and the evaluation of the acute skin reaction following irradiation. (author)
Manrique, Elizabeth; Enfield, N J
Practices of other-initiated repair deal with problems of hearing or understanding what another person has said in the fast-moving turn-by-turn flow of conversation. As such, other-initiated repair plays a fundamental role in the maintenance of intersubjectivity in social interaction. This study finds and analyses a special type of other-initiated repair that is used in turn-by-turn conversation in a sign language: Argentine Sign Language (Lengua de Señas Argentina or LSA). We describe a type of response termed a "freeze-look," which occurs when a person has just been asked a direct question: instead of answering the question in the next turn position, the person holds still while looking directly at the questioner. In these cases it is clear that the person is aware of having just been addressed and is not otherwise accounting for their delay in responding (e.g., by displaying a "thinking" face or hesitation, etc.). We find that this behavior functions as a way for an addressee to initiate repair by the person who asked the question. The "freeze-look" results in the questioner "re-doing" their action of asking a question, for example by repeating or rephrasing it. Thus, we argue that the "freeze-look" is a practice for other-initiation of repair. In addition, we argue that it is an "off-record" practice, thus contrasting with known on-record practices such as saying "Huh?" or equivalents. The findings aim to contribute to research on human understanding in everyday turn-by-turn conversation by looking at an understudied sign language, with possible implications for our understanding of visual bodily communication in spoken languages as well. PMID:26441710
Freyre, M R; Baigorria, C M; Rozycki, V R; Bernardi, C M; Charpentier, M
The nutritional value of wild underexploited vegetable samples collected in the Argentine Chaco was investigated. Leaves from Hipochaeris sp.-, Coronopus didimus and Portulaca olearacea; fruits from Zyziphus sativa, Brumelia obtusifolia and Eugenia uniflora; and roots of Canna coccinea were included in this work; several separate samples being taken at least during two consecutive harvesting seasons. Values for moisture, protein, total lipids, crude fiber, ash, reducing and total sugars, starch, total pectins and energy are given. Mineral micronutrient contents are reported for calcium, potassium, magnesium, iron and phosphorus, as well as vitamin values (ascorbic acid and beta-carotene). Higher concentrations of macronutrients were found in the leafy vegetables (32-50 Kcal/100 g) than in commercially exploited cultivars (14-30 Kcal/100 g), as shown by an increased energy value, the protein content of Portulaca olearacea (3.74 g/100 g) being highly remarkable. Unusually high micronutrient figures were also determined in Coronopus didimus, with 172.3; 3.98, and 46.7 mg/100 g, for calcium, iron and magnesium, respectively. In general, fruits also showed higher macronutrient contents, with the exception of proteins, with less but constant values (1.58 to 1.74 g/100 g), although contributing more energy than commercial cultivars (70 to 147 Kcal/100 g). Equally important proved to be the provitamin A content in Eugenia uniflora (11.98 mg/100 g). Roots of Canna coccinea revealed the lowest energy value (34 Kcal/100 g) but surprisingly, the highest content of phosphorus of all the species under study. PMID:11464672
Huff, W.D.; Bergstrom, Stig M.; Kolata, Dennis R.; Cingolani, C.A.; Astini, R.A.
This paper is included in the Special Publication entitled 'The proto- Andean margin of Gondwana', edited by R.J. Pankhurst and C.W. Rapela. Ordovician K-bentonites have now been recorded from >20 localities in the vicinity of the Argentine Precordillera. Most occur in the eastern thrust belts, in the San Juan Limestone and the overlying the Gualcamayo Formation, but a few ash beds are known also from the central thrust belts. The oldest occur in the middle Arenig I, victoriae lunatus graptolite (Oe. evae conodont) Zone, and the youngest in the middle Llanvirn P. elegans (P. suecicus) Zone. Mineralogical characteristics, typical of other Ordovician K-bentonites, include a matrix of illite/smectite mixed-layer clay and a typical felsic volcanic phenocryst assemblage: biotite, beta-form quartz, alkali and plagioclase feldspar, apatite, and zircon, with lesser amounts of hornblende, clinopyroxene, titanite and Fe-Ti oxides. The proportions of the mineral phases and variations in their crystal chemistry are commonly unique to individual (or small groups of) K-bentonite beds. Glass melt inclusions preserved in quartz are rhyolitic in composition. The sequence is unique in its abundance of K-bentonite beds, but a close association between the Precordillera and other Ordovician sedimentary basins cannot be established. The ash distribution is most consistent with palaeogeographical reconstructions in which early Ordovician drifting of the Precordillera occurred in proximity to one or more volcanic arcs, and with eventual collision along the Andean margin of Gondwana during the mid-Ordovician Ocloyic event of the Famatinian orogeny. The Puna-Famatina terrane northeast of the Precordillera might have served as the source of the K-bentonite ashes, possibly in concert with active arc magmatism on the Gondwana plate itself.
Pedraza De Marchi, A. C.; Ghidella, M. E.; Tocho, C.
The segment of Argentine continental margin located between 39°S and the Malvinas platform (~49°S) is of passive type and volcanic characteristics revealed by seaward-dipping seismic reflectors sequences (SDRs). The free air gravity edge-effect associated with passive continental margins is one of the most distinctive characteristics of gravity in marine regions. This effect is in large part due to the transition between continental and oceanic crusts, because of their different thicknesses. In this presentation we investigate the Airy type isostatic compensation scheme by using three interfaces in a forward calculation with different approximations of Parker's expression to obtain the isostatic anomaly. After that we perform the inversion of the anomaly thus obtained in order to find the Moho's deflection necessary to compensate it (or minimize it) by using the same scheme of interfaces and the iterative Parker-Oldenburg method (Oldenburg, D., 1974) with more terms in the inversion. The crust-mantle interface (Moho) thus calculated represents a more realistic surface than the one calculated using one term in the inversion and the surface estimated with topographic data and sediment thickness. Even considering that the experiment constitutes a schematic assumption just to test the numerical methods involved, we find that in the comparison with the only available digitized refraction profile, the inverted Moho interface reproduces fairly well the Moho that the seismic profile yields, for the case of the iterative method. This suggests that the inverse calculation with the iterative method is sensible to the presence of the SDRS, at least for this sole profile. Keywords: isostatic anomaly, Moho, passive continental margins Oldenburg, D., 1974. The inversion and interpretation of gravity anomalíes, Geophysics, vol. 39, no. 4, p. 526-536.
Martens, Frederick H. [Argonne National Laboratory; Jacobson, Norman H.
This booklet discusses research reactors - reactors designed to provide a source of neutrons and/or gamma radiation for research, or to aid in the investigation of the effects of radiation on any type of material.
This article proposes an overview of research reactors, i.e. nuclear reactors of less than 100 MW. Generally, these reactors are used as neutron generators for basic research in matter sciences and for technological research as a support to power reactors. The author proposes an overview of the general design of research reactors in terms of core size, of number of fissions, of neutron flow, of neutron space distribution. He outlines that this design is a compromise between a compact enough core, a sufficient experiment volume, and high enough power densities without affecting neutron performance or its experimental use. The author evokes the safety framework (same regulations as for power reactors, more constraining measures after Fukushima, international bodies). He presents the main characteristics and operation of the two families which represent almost all research reactors; firstly, heavy water reactors (photos, drawings and figures illustrate different examples); and secondly light water moderated and cooled reactors with a distinction between open core pool reactors like Melusine and Triton, pool reactors with containment, experimental fast breeder reactors (Rapsodie, the Russian BOR 60, the Chinese CEFR). The author describes the main uses of research reactors: basic research, applied and technological research, safety tests, production of radio-isotopes for medicine and industry, analysis of elements present under the form of traces at very low concentrations, non destructive testing, doping of silicon mono-crystalline ingots. The author then discusses the relationship between research reactors and non proliferation, and finally evokes perspectives (decrease of the number of research reactors in the world, the Jules Horowitz project)
Mathematical methods and computer calculations for nuclear and thermonuclear reactor kinetics, reactor physics, neutron transport theory, core lattice parameters, waste treatment by transmutation, breeding, nuclear and thermonuclear fuels are the main interests of the conference
There are currently 284 research reactors in operation, and 12 under construction around the world. Of the operating reactors, nearly two-thirds are used exclusively for research, and the rest for a variety of purposes, including training, testing, and critical assembly. For more than 50 years, research reactor programs have contributed greatly to the scientific and educational communities. Today, six of the world's research reactors are being shut down, three of which are in the USA. With government budget constraints and the growing proliferation concerns surrounding the use of highly enriched uranium in some of these reactors, the future of nuclear research could be impacted
Object: To provide a jet and missile protective wall of a configuration being inflated toward the center of a reactor container on the inside of a body of the reactor container disposed within a biological shield wall to thereby increase safety of the reactor container. Structure: A jet and missile protective wall comprised of curved surfaces internally formed with a plurality of arch inflations filled with concrete between inner and outer iron plates and shape steel beam is provided between a reactor container surrounded by a biological shield wall and a thermal shield wall surrounding the reactor pressure vessel, and an adiabatic heat insulating material is filled in space therebetween. (Yoshino, Y.)
Vega, S Y; Rust, M K
The foraging range and distribution of Argentine ant, Linepithema humile (Mayr), colonies in urban areas of southern California extended at least 61 m (200 feet) from feeding stations and structures. Ants were fed at 25% sucrose feeding stations containing 0.01% fluorescent brighter (FB28). Within 14 d, from 77-90% of the ants sampled next to the feeding stations were positive for FB28. The percentage of ants with FB28 declined gradually to approximately 55% 61 m away from the feeding station. The percentage of marked ants in the controls didn't change over the 4-wk-test period. There were approximately 290,000 ants visiting the monitored stations each night before treatments. The 0.0001% fipronil baits and 0.06% fipronil SC sprays provided significant reductions in at least 4 wk. The percentage of ants marked with FB28 decreased significantly in both bait and spray treatments over 4 wk suggesting that the resurgence of ants in treated areas were because of immigration from untreated areas. It is likely that much larger areas will need to be treated to control Argentine ants in urban settings, especially if baits are being used. PMID:12852625
Hydroacoustical evidence of the expansion of pelagic swarms of Munida gregaria (Decapoda, Munididae) in the Beagle Channel and the Argentine Patagonian Shelf, and its relationship with habitat features
Diez, Mariano J.; Cabreira, Ariel G.; Madirolas, Adrián; Lovrich, Gustavo A.
Squat lobsters are highly diversified and widespread decapods, of which only three species form pelagic swarms. Here we infer the expansion of Munida gregaria populations in the Beagle Channel and the Argentine Patagonian Shelf by means of acoustic surveys of pelagic swarms. We also describe the habitat characteristics in which these swarms occur. Acoustic data was collected during three multidisciplinary scientific cruises on board of the R/V Puerto Deseado during 2009, 2012 and 2014. Despite differences in the environmental conditions between the two surveyed areas, between 2009 and 2014 pelagic swarms increased their occurrence and abundance both in the Beagle Channel and on the Argentine Patagonian Shelf. Towards the end of the studied period, pelagic swarms of M. gregaria occurred in new locations, supporting the notion of a population expansion. Within the Beagle Channel swarm expansions were more marked than on the Patagonian Shelf. We here postulate that M. gregaria expansions occur in association with productive areas of the Argentine continental shelf, such as frontal zones, favoured by the squat lobster phenotypic plasticity that permit to exploit resources in both the neritic and benthic environments. At a regional scale on the Patagonian Shelf, three main groups of pelagic swarms of M. gregaria were clearly associated to respective frontal zones. The information presented here is necessary to understand fluctuations in both distribution and abundance patterns of a key species on the Argentine continental shelf. These fluctuations could be direct or indirect indicators of changes in the ecosystem.
From its creation in 1967, the Argentine Radioprotection Society (SAR) has as basic purpose promoting all the aspects related with the radiological protection and the nuclear safety. Due to the great increment in the use of radioactive sources in diverse areas, soon it was evident for the SAR the importance and necessity to promote the knowledge of the radioprotection approaches between the users of radioactive sources and ionizing radiations in all its application fields, be these industrial, academic or doctors. From the year 2000, the SAR comes organizing in regular and periodical form basic and specialized courses about radiological safety of radioactive sources for industrial use and profile of oil wells, among others. In this work, the characteristics of the different dictated courses are described whose programs have been developed keeping in mind the requirements of the competent authorities of Argentina. Also, statistical information on the dictated courses and its participants is presented. The number of dictated courses was incremented from 6 (year 2000) up to 16 (year 2005), being also increased significantly the number of participants for course. The dictated courses are theoretical-practical, with a duration average of 20 hs. The educational body is constituted by specialists in the different topics with recognized experience. Its given to the participants notes and support material, as well as copies of the material presented to develop the course. When concluding the courses, its deliver to the participants certifies of attendance and/or approval, as it corresponds. In their headquarters the SAR has didactic facilities and specific equipment for the dictation of the courses. Also accounts with the easiness of dictating those courses outside of their headquarters. This is particularly advantageous for companies or organizations that are seated in points far from the main cities and they should qualify in radiological safety to the personnel but, by
The Argentine Republic has extensive antecedents in education and training in radiological protection. From the beginning of the nuclear activity in the country was given preponderance to the aspects related with the radiological protection and the personnel's training involved in the employment of ionizing radiations. At the present time these educational activities already overcome the 50 years, there being accumulated a rich and important experience in the matter. In the country the organisms that have assigned by law the responsibility of the regulation and the control of practice them with ionizing radiations are the Nuclear Regulatory Authority and the Ministry of Health and Atmosphere of the Nation. The first one has the mission of protecting people of the noxious effects of the ionizing radiations derived of nuclear activities, the second is in charge of the control of the equipment dedicated specifically to generate X-rays. This includes the responsibility of elaborating, to emit and to make complete the regulations, standards and other corresponding requirements, in particular - in the mark of the present work - regarding to establish demands and to promote education activities and training in radiological protection. The sure use of the benefits that offers the nuclear development in its diverse applications implies to overturn resources, experience and dedication for the personnel's training. In that sense the Argentina has committed recently to undertake the necessary actions to constitute a Regional Center of Education and Training for Latin America and the Caribbean, taking advantage of the important experience obtained in more of 25 years of imparting graduate degree courses in radiological protection and nuclear safety with inter regional and regional character. With that purpose a process of self evaluation has begun (self appraisal), following the limits settled down by the International Atomic Energy Agency in the document 'Education and
José Camilo Bedano
Full Text Available Soil is the most basic resource for sustainable agricultural production; it promotes water quality, is a key component of the biogeochemical cycles and hosts a huge diversity of organisms. However, we are not paying enough attention to soil degradation produced by land use. Modern agriculture has been successful in increasing yields but has also caused extensive environmental damage, particularly soil degradation. In the Argentine Pampas, agriculturization reached a peak with the generalized use of the no-till technological package: genetically modified soybeans tolerant to glyphosate, no-till, glyphosate, and inorganic fertilizers. This phenomenon has been widely spread in the country; the no-till package has been applied in large areas and has been used by tenants in a 60%–70% of cultivated lands. Thus, those who were involved in developing management practices may not be the same as those who will face degradation issues related to those practices. Indeed, most evidence reviewed in this paper suggests that the most widely distributed practices in the Pampas region are actually producing severe soil degradation. Biological degradation is particularly important because soil biota is involved in numerous soil processes on which soil functioning relies, affecting soil fertility and productivity. For example, soil meso- and macrofauna are especially important in nutrient cycling and in soil structure formation and maintenance, and they are key components of the network that links microbial process to the scale of fields and landscapes where ecosystem services are produced. However, the knowledge of the impact of different agricultural managements on soil meso- and macrofauna in Pampas agroecosystems is far from conclusive at this stage. The reason for this lack of definite conclusions is that this area has been given less attention than in other parts of the world; the response of soil fauna to agricultural practices is complex and taxa
This paper is addressed particularly to the scientific community users and, as a whole, to any individual in society, whichever his profession or working environment, who is interested in getting acquainted of improving his/her knowledge in the areas of radiological protection and nuclear safety, as well as in other related areas of medicine, biology, engineering, mathematics and physics. The purpose of this paper is the diffusion of the broad spectrum of bibliography and the introduction of the technological-computerized media utilized as tools by the Argentine National Board of Nuclear Regulation in providing responses to a huge number of both internal and external requests for information. There is a large number of professionals and/or researchers who visit the facilities of our Information Center or who get in touch - through the post service, e-mail or telephone - consulting on the available material, either in paper (books, periodical publications, etc.) or in the form of microfilms, video, tapes, CD-ROM, etc. This paper is both descriptive and explanatory; a description is provided of the bibliographical material managed by the Information Center and a brief explanation is given on the techniques and methods used in providing the information requested by the users. Fundamentally, the Center's bibliographical material includes: periodical publications, books, reports, microfilms, etc., all of them related to radiological protection and nuclear safety. Data bases are available in CD-ROM, the most important one being the International Nuclear Information System (INIS) developed by the International Atomic Energy Agency (IAEA). The Center has also its own data bases, such as the GPRS (primary documents) and standards (both domestic and international), UNESCO's MicroIsis software is used for the Center's data bases: PERSIS (periodical publications), DOCSIS (books) and ARCAL (magazines from the Latin American territory). This paper will definitely serve as a safe
The whole reactor building is accommodated in a shaft and is sealed level with the earth's surface by a building ceiling, which provides protection against penetration due to external effects. The building ceiling is supported on walls of the reactor building, which line the shaft and transfer the vertical components of forces to the foundations. The thickness of the walls is designed to withstand horizontal pressure waves in the floor. The building ceiling has an opening above the reactor, which must be closed by cover plates. Operating equipment for the reactor can be situated above the building ceiling. (orig./HP)
The microscopic study of a cell is meant for the determination of the infinite multiplication factor of the cell, which is given by the four factor formula: K(infinite) = n(epsilon)pf. The analysis of an homogeneous reactor is similar to that of an heterogeneous reactor, but each factor of the four factor formula can not be calculated by the formulas developed in the case of an homogeneous reactor. A great number of methods was developed for the calculation of heterogeneous reactors and some of them are discussed. (Author)
Recently there has arisen a significant interest in small and modular reactors (SMRs) in the U.S. the Obama Administration has initiated a program to support the development of such reactors and at least one U.S. utility - the Tennessee Valley Authority (TVA) seems willing to commit to the commercialization of one promising U.S. SMR design. In parallel other international programs for the development of SMRs have gathered further momentum. Among them are the SMR programs in Russia, Argentina and India. These national programs were coordinated through the INPRO program of the International Atomic Energy Agency (IAEA). Within the INPRO program the currently operating Indian 220 MWe Pressurize Heavy Water Reactors (PHWRs) and the newly developed Advanced Heavy Water Reactor (AHWR) can be considered SMRs. The AHWR has already figured prominently in the work of the IAEA. Some of the more interesting SMR designs now being developed are described. Among them are the U.S. mPower and Nuscale designs, the Russian KLT-40 design, the Argentine CAREM and Korean SMART designs, and the India AHWR design. In all cases the unique and salient points of each design and its specific application is described
During the last quarter of 2000, in the Radioactive Waste Management Area of the Argentine National Commission of Atomic Energy (CNEA), located at Ezeiza Atomic Center (CAE), activities associated to the shipment of 207 MTR spent fuels containing high enrichment uranium were carried out within the Foreign Research Reactor/Domestic Research Reactor Receipt Program launched by the US Department of Energy (DOE). The MTR spent fuel shipped to Savannah River Site (SRS) was fabricated in Argentina with 90% enriched uranium of US origin and it was utilized in the operation of the research and radioisotope production reactor RA-3 from 1968 until 1987. After a cooling period at the reactor, the spent fuel was transferred to the Central Storage Facility (CSF) located in the waste management area of CAE for interim storage. The spent fuel (SF) inventory consisted of 166 standard assemblies (SA) and 41 control assemblies (CA). Basically, the activities performed were the fuel conditioning operations inside the storage facility (remote transference of the assemblies to the operation pool, fuel cropping, fuel re-identification, loading in transport baskets, etc.) conducted by CNEA. The loading of the filled baskets in the transport casks (NAC-LWT) by means of intermediate transfer systems and loaded casks final preparations were conducted by NAC personnel (DOE's contractor) with the support of CNEA personnel. (author)
David W. Nigg; Amanda E. Schwint; John K. Hartwell; Elisa M. Heber; Veronica Trivillin; Jorge Castillo; Luis Wentzeis; Patrick Sloan; Charles A. Wemple
Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.
Nigg, D.W.; Schwint, A.E.; Hartwell, J.K.; Heber, E.M.; Trivillin, V.; Castillo, J.; Wentzeis, L.; Sloan, P.; Wemple, C.A.
Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.
The document reproduces the text of the Protocol of 30 August 1996 suspending the application of safeguards under the Agreement between the Agency and the Government of Argentina and the Federal Republic of Germany concerning the Agency's assistance for the establishment of a training reactor project in Argentina, which entered into force on 13 March 1970, in light of the provisions for the application of safeguards pursuant to the quadripartite safeguards agreement between Argentina, Brazil, the Brazilian-Argentine Agency for the Accounting and Control of Nuclear Materials and the IAEA
The document reproduces the text of the Co-operation Agreement between the International Atomic Energy Agency and the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials which entered into force on 25 May 1998
Molina Mansilla, Ricardo; Erra Serrabasa, Pilar; Bertrán Serra, Enric
[EN] A plasma reactor that can operate in a wide pressure range, from vacuum and low pressures to atmospheric pressure and higher pressures. The plasma reactor is also able to regulate other important settings and can be used for processing a wide range of different samples, such as relatively large samples or samples with rough surfaces.
Progress in research on reactor physics in 1997 at the Belgian Nuclear Research Centre SCK/CEN is described. Activities in the following four domains are discussed: core physics, ex-core neutron transport, experiments in Materials Testing Reactors, international benchmarks
The application of biotechnology principles to metals recuperation from minerals or industrial wastes is a recent technology. It essentially consists in the utilization of bacteria which act as catalysts of metallic sulfur oxidation. This oxidation directly or indirectly produces soluble products from compounds present in the insoluble minerals in the lixiviating fluids media, as copper, cobalt, nickel sulfurs, uranium (IV) oxide and manganese (IV) oxide. The results obtained using Thiobacillus ferrooxidans and Thiobacillus thiooxidans bacteria permitted to establish the application of this technique to the Argentine minerals. The main advantages of the bacterian lixiviation lie upon its application to low content minerals, at low installation and operating costs and at important effects absence of environmental contamination. (Author)
Mémoires de Géosciences Rennes, n° 92, 381 p., ISBN: 2-905532-91-2 Les Andes Centrales sont l'exemple type d'une chaîne se développant le long d'une marge active en contexte non collisionel et résultent de la subduction légèrement oblique (-N75°E) de la plaque océanique Nazca sous le continent sud-américain. Elles sont caractérisées par la présence du haut plateau de l'Altiplano-Puna s'étendant depuis le Pérou au Nord jusqu'en Argentine au Sud et présentant une altitude moyenne avoisinant ...
La gestion des déchets à Buenos Aires, métropole argentine de 14,5 millions d’habitants, a connu des reconfigurations importantes depuis les années 2000. Les revendications citoyennes en faveur d’une gestion plus respectueuse de l’environnement émergent en pleine crise de 2001, et ne sont pas sans rappeler les débuts du système sociotechnique instauré en 1977. Au lendemain du coup d’État militaire, le gouvernement de facto lançait l’un des projets d’aménagement du territoire métropolitain des...
The need to create in the Argentine public opinion new positives symbols and images on nuclear energy and on the benefits of its peaceful applications, is al present so important as the development of new technical tools to improve the nuclear industry. These positives symbols and imagines on nuclear energy must be created in the framework of a joint strategy of all the country's nuclear institutions as well as other public organizations, in view of the new nuclear plan recently announced. This joint strategy will permit to create not only the new positives symbols and images in the public opinion, but also to obtain the support of the mass media and new spaces for negotiation in the national, provincial and municipal levels. (author)
Silvia R Tandeciarz
Full Text Available Since the end of the last Argentine Dictatorship (1976-1983, a number of feature-length films have engaged in the public debate over the legacies of state terrorism. El secreto de sus ojos (2009, Argentina's most recent Oscar winner, is the latest to do so, exploring the effects of more than a decade of impunity on those who lost their loved ones. Suggesting that restoration of a justice system that works can lead to the restoration of full civic engagement in a healthy body politic, the film raises important questions about citizenship and belonging in a post-national era. This essay explores the film's phenomenal success in the global memory market to illuminate what remains at stake in contemporary narratives of reconciliation.
The Argentine RA-3 research reactor (with U3O8-Al LEU MTR fuel type elements and in the process to increase its power from 5 MW to 10 MW since October 2002) is operated by the National Atomic Energy Commission (CNEA). After evaluating the safety studies submitted by CNEA, the Argentine Nuclear Regulatory Authority (ARN) authorised the irradiation of two U3Si2-Al prototype fuel elements named P-06 and P-07, in the RA-3, in September 2000 and September 2001 respectively. These irradiations are part of the qualification programme as manufacturer (CNEA). This report contains a brief description of the regulatory process the ARN carries out in order to approve major modifications or new experiments in research reactors; it also summarises conditions in force for operable core configurations, considers a definition of prototype fuel element and lists the main characteristics of the RA-3 research reactor. Then, the process involved in the authorisation to irradiate the prototypes P-06 and P-07 is particularly analysed. Finally, and in case an authorisation to irradiate a prototype fuel element of a non-qualified material (such as U-Mo) in the RA-3 is requested, the regulatory aspects that should be taken into consideration are analysed. This would be the first time a question of this nature is submitted to the ARN. (author)
its emergence with general social and economic processes?; How can we extract the incidents of this idea?; How can we characterize and classify its main expressions?; How can we think about the global meaning of this ideological and political process? The general exposition of the research is focused on showing that the topic of the failure acquired its decisive attributes during the first half of the 20th century, through a complex dynamic, comprised of diverse channels which should be captured in their specificity, although without losing sight of the more general movement of which they form a part: seen globally, this movement contributed to the erosion of an entire ideological-cultural configuration, which I call "argentine illusion". The backdrop of the process was none other than the growing social complexity, the greater and more dissonant discursive diversification (Tulio Halperín and the profound hegemony crisis which the country experienced throughout the period.
Full Text Available High-field Nuclear Magnetic Resonance (NMR spectroscopy and Gas Chromatography (GC were used to analyze 16 monovarietal olive oils obtained from few matched Mediterranean cultivars grown in experimental fields located in Italy and in the Catamarca region of Argentina. The Catamarca region is characterized by extreme pedoclimatic conditions and by a wild spontaneous vegetation. The proposed sampling allows to study the effect of different pedoclimatic conditions on olive oil composition. GC gives the fatty acid profile of olive oil samples. 1H and 13C NMR techniques provide different information: the 1H NMR spectrum allows the measurement of minor components of olive oils such as b-sytosterol, hexanal, trans-2-hexenal, formaldehyde, squalene, cycloartenol and linolenic acid; the 1C NMR spectrum allows to obtain information about glycerol tri-esters of olive oils, i.e., about their acyl composition and positional distribution on glycerol moiety. All the NMR and GC results have been submitted to Linear Discriminant Analysis (LDA and Tree Cluster Analysis (TCA. A careful analysis of the statistical results allows to select the Mediterranean cultivars less affected by the climatic conditions present in the Catamarca region. The selected cultivars produce olive oils which keep their Mediterranean characteristics and which can be proposed as colonizing plants in this wild Argentine region.La espectroscopía de Resonancia Magnética Nuclear de alta resolución (RMN y Cromatografía Gaseosa (CG fueron utilizadas para analizar 16 monovariedades de aceites de oliva, obtenidas de algunos olivares Mediterráneos cultivados contemporáneamente en campos experimentales localizados en Italia y en la región de Catamarca en Argentina. Estas muestras permiten estudiar diferentes condiciones pedoclimáticas en la composición de los aceite de oliva. La CG proporciona el perfil en ácidos grasos de los aceites de oliva y las técnicas RMN 1H y RMN 13C suministran
Full Text Available Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no-tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional
Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date
The RA-6 reactor at the Bariloche Atomic Centre was designed mainly as a teaching tool. During its almost 21 years, after the first criticality, it was used as a support for several graduate and post graduate careers at the Balseiro Institute, depending on the Argentine National Atomic Energy Commission and the Cuyo National University. Besides these tasks, a big work was done in research and development using the synergy produced by the close relationship between the students and researchers. Main characteristics of the reactor are described. An outline of use for teaching and training is given. Research activities resulting from appropriate personnel management and students' cooperation that allowed achieving different grades of development are described. (author)
A design requirement aimed at limiting the discharge of globally dispersed long-lived radionuclides released by nuclear power reactors was in force in Argentine since 1979 till recently. The practical results of such regulatory measure was the need to retain C-14 in the PHWR under construction, as well as in furniture heavy water reactors to be built in the country. This paper explains the basis of such requirement, which was formulated as a collective dose constraint per unit of energy generated, and the main assumptions that triggered it. The differences between the assumptions made at the time and the reality of nuclear power generation at the beginning of the 21st century, as well as their implications in relation to the requirement are described, including the Suess effect and its impact in the total dose due to C-14. Finally, the facts that made no longer reasonable to keep in force the above mentioned requirement are presented. (author)
A nuclear reactor is described comprising fissionable material dispersed in graphite blocks, helium filling the voids of the blocks and the spaces therebetween, and means other than the helium in thermal conductive contact with the graphite for removing heat.
Miller, H.I.; Smith, R.C.
This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.
This draft chart contains graphical symbols from which the type of (nuclear) reactor can be seen. They will serve as illustrations for graphical sketches. Important features of the individual reactor types are marked out graphically. The user can combine these symbols to characterize a specific reactor type. The basic graphical symbol is a square with a point in the centre. Functional groups can be depicted for closer specification. If two functional groups are not clearly separated, this is symbolized by a dotted line or a channel. Supply and discharge lines for coolant, moderator and fuel are specified in accordance with DIN 2481 and can be further specified by additional symbols if necessary. The examples in the paper show several different reactor types. (orig./AK)
The Argentine electric market indicative planning. The transport systems reference guides; Planificacion indicativa del mercado electrico argentino. Las guias de referencia de los sistemas de transporte
Nizovoy, Jorge Alberto; Puleri, Cesar Anibal [Transener S.A., Buenos Aires (Argentina)]. E-mail: Jorge.Nizovoy@transx.com.ar
This work describes the foreseen tool in the Argentine electric market to guide the users regarding transport systems probable evolution, whereas they have to make inversion decisions in order to enlarge the power transportation networks. The Transportation System Reference Guides constitute such tools. Besides referring to its contents and experiences that have guided to improvements on its edition process, the work approaches aspects of the Argentine electric system development, which illustrate the challenger context on which they have been accomplishing and the obtained knowledge from comparison between what has been really accomplished and what has been proposed by the guides. For this, it is used the Transener S.A. company private experience by means of real examples from its seven published Reference Guides.
Multifunctional reactors are single pieces of equipment in which, besides the reaction, other functions are carried out simultaneously. The other functions can be a heat, mass or momentum transfer operation and even another reaction. Multifunctional reactors are not new, but they have received much emphasis in research in the last decade. A survey is given of modern developments and the first successful applications on a large scale. It is explained why their application in many instances is ...
A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)
In order to reduce neutron embrittlement of the pressue vessel of an LWR, blanked off elements are fitted at the edge of the reactor core, with the same dimensions as the fuel elements. They are parallel to each other, and to the edge of the reactor taking the place of fuel rods, and are plates of neutron-absorbing material (stainless steel, boron steel, borated Al). (HP)
The reasons for the development of fast reactors are briefly reviewed (a propitious neutron balance oriented towards a maximum uranium burnup) and its special requirements (cooling, fissile material density and reprocessing) discussed. The three stages in the French program of fast reactor development are outlined with Rapsodie at Cadarache, Phenix at Marcoule, and Super Phenix at Creys-Malville. The more specific features of the program of research and development are emphasized: kinetics and the core, the fuel and the components
On 11 May 1994, the Director General received a note verbale from the Permanent Mission of Argentina to the International Atomic Energy Agency relating to the export of nuclear material, equipment and technology. The purpose of this note verbale is to provide further information on nuclear export policies and practices of the Government of the Argentine Republic. In the light of the wish expressed at the end of the note verbale, the text of the note verbale is annexed hereto
González, Andrea; Hallak, Juan Carlos; Schott, Peter; Genta, Tatiana Soria
This paper describes experiences of international insertion of Argentine producers of manufactured goods not oriented to the mass market. Based on these experiences, we develop a typology of potential alternatives of international insertion for this type of goods centered on the role of local agents in design activities. Our analysis follows the global value chain (GVC) approach and emphasizes the links between local producers and buyers in developed countries. First, we analyze experiences o...
G. D. Wells; Rodger, A. S.; Moffett, R. J.; G. J. Bailey; Fuller-Rowell, T. J.
In the past the global, fully coupled, time-dependent mathematical model of the Earth's thermosphere/ionosphere/plasmasphere (CTIP) has been unable to reproduce accurately observed values of the maximum plasma frequency, foF2, at extreme geophysical locations such as the Argentine Islands during the summer solstice where the ionosphere remains in sunlight throughout the day. This is probably because the seasonal dependence of thermospheric cooling by 5.3 µm nitric oxid...