Ionospheric response to the 2009 sudden stratospheric warming over the equatorial, low, and middle latitudes in the South American sector

The present study investigates the ionospheric total electron content (TEC) and F-layer response in the Southern Hemisphere equatorial, low, and middle latitudes due to major sudden stratospheric warming (SSW) event, which took place during January-February 2009 in the Northern Hemisphere. In this study, using 17 ground-based dual frequency GPS stations and two ionosonde stations spanning latitudes from 2.8°N to 53.8°S, longitudes from 36.7°W to 67.8°W over the South American sector, it is observed that the ionosphere was significantly disturbed by the SSW event from the equator to the midlatitudes. During day of year 26 and 27 at 14:00 UT, the TEC was two times larger than that observed during average quiet days. The vertical TEC at all 17 GPS and two ionosonde stations shows significant deviations lasting for several days after the SSW temperature peak. Using one GPS station located at Rio Grande (53.8°S, 67.8°W, midlatitude South America sector), it is reported for the first time that the midlatitude in the Southern Hemisphere was disturbed by the SSW event in the Northern Hemisphere.Fil: Fagundes, P. R.. Universidade do Vale do Paraíba; BrasilFil: Goncharenko, L. P.. Massachusetts Institute of Technology; Estados UnidosFil: De Abreu, A. J.. Universidade do Vale do Paraíba; BrasilFil: Venkatesh, K.. Universidade do Vale do Paraíba; BrasilFil: Pezzopane, M.. Istituto Nazionale Di Geofisica E Vulcanologia; ItaliaFil: De Jesus, R.. Universidade do Vale do Paraíba; BrasilFil: Gende, Mauricio Alfredo. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Coster, A. J.. Massachusetts Institute of Technology; Estados UnidosFil: Pillat, V. G.. Universidade do Vale do Paraíba; Brasi

The electronic Space Weather upper atmosphere (eSWua) project at INGV: advancements and state of the art

The eSWua project is based on measurements performed by all the instruments installed by the upper atmosphere physics group of the Istituto Nazionale di Geofisica e Vulcanologia, Italy and on all the related studies. The aim is the realization of a hardware-software system to standardize historical and real-time observations for different instruments. <br><br> An interactive Web site, supported by a well organized database, can be a powerful tool for the scientific and technological community in the field of telecommunications and space weather. The most common and useful database type for our purposes is the relational one, in which data are organized in tables for petabytes data archiving and the complete flexibility in data retrieving. <br><br> The project started in June 2005 and will last till August 2007. In the first phase the major effort has been focused on the design of hardware and database architecture. The first two databases related to the DPS4 digisonde and GISTM measurements are complete concerning populating, tests and output procedures. Details on the structure and Web tools concerning these two databases are presented, as well as the general description of the project and technical features

The New AIS-INGV Ionosonde at Italian Antarctic Observatory

The Italian Ionospheric Antarctic Observatory of Terra Nova Bay (74.70S, 164.11E) was recently equipped with the AIS-INGV ionosonde developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, (Italy). This paper aims to describe briefly which are the main characteristics of the instrument and show the good quality and reliability of the recorded ionograms

Ionospheric Observatory Development At Mario Zucchelli Station

Since 1995 Italian Ionospheric Antarctic Observatory at Terra Nova Bay, now “MARIO ZUCCHELLI”, station (geographic coordinates: 74.70°S, 164.11°E) performs continuous and systematic ionospheric vertical soundings. Long time series of continuous and accurate ionospheric observations (more than one solar cycle) are necessary for a deeper understanding of the complex phenomena occurring in the upper atmosphere at high latitude; furthermore high rate soundings (at least four soundings per hour or more) contribute to the short-time prediction of the radiopropagation conditions and to the Space Weather. During 2003–2004 Antarctic campaign a new digital ionosonde, recently developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome, (Italy), has been installed the Ionospheric Observatory and preliminary tests have been carried out. This new Advanced Ionospheric Sounder-INGV, briefly AIS, is integrated in a stand alone system during winter time: the sounding, device settings and data sending to Rome are completely automatic and remote programmable. Ionograms are available on line at the INGV web and ftp server. The new features of the Ionospheric Observatory are presented and preliminary statistics on the reliability and validation of the experimental observation are shown and discussed

The electronic Space Weather upper atmosphere (eSWua) project at INGV: advancements and state of the art

The eSWua project is based on measurements performed by all the instruments installed by the upper atmosphere physics group of the Istituto Nazionale di Geofisica e Vulcanologia, Italy and on all the related studies. The aim is the realization of a hardware-software system to standardize historical and real-time observations for different instruments. An interactive Web site, supported by a well organized database, can be a powerful tool for the scientific and technological community in the field of telecommunications and space weather. The most common and useful database type for our purposes is the relational one, in which data are organized in tables for petabytes data archiving and the complete flexibility in data retrieving. The project started in June 2005 and will last till August 2007. In the first phase the major effort has been focused on the design of hardware and database architecture. The first two databases related to the DPS4 digisonde and GISTM measurements are complete concerning populating, tests and output procedures. Details on the structure and Web tools concerning these two databases are presented, as well as the general description of the project and technical features

New low power pulse compressed ionosonde at Gibilmanna Ionospheric Observatory

A digital low power pulse compressed ionosonde was developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy. The aim of this Advanced Ionospheric Sounder, AIS-INGV, is to reduce the transmitted power and, consequently, weight, size, power consumption and hardware complexity. To compensate the power reduction the most advanced HF radar techniques such as the pulse compression and a phase coherent integration are used. The ionosonde is completely programmable and a PC supports the data acquisition, control, storage and on-line processing. The first prototype was installed at Gibilmanna Ionospheric Observatory (Sicily), an interesting location in the center of Mediterranean area. The new ionosonde will contribute to ionospheric database and real time knowledge of South European ionospheric conditions for space weather applications. In this work the first results (ionograms and autoscaled characteristics) are presented and briefly discussed

Avaliação da tolerância de acesso do gênero Paspalum ao sombreamento.

Editado por Ana Rita de Araújo Nogueira, Simone Cristina Meo Niciura

Growth of native trees in two agroforestry systems.

Agroforestry systems with eucalyptus prevail in Central and Southeast Brazil, and little information is available about systems using native trees. The aim of the present study was to evaluate the development of seven native tree species grown under two agroforestry systems. The experiment was conducted starting in 2007 in 12-hectare area in the municipality of São Carlos, São Paulo state, Brazil. The tree species planted in the two systems (a silvopastoral system and an agrisilvicultural system) were: 'capixingui' (Croton floribundus) and 'mutambo' (Guazuma ulmifolia) (tutors), 'jequitibá-branco' (Cariniana estrellensis), 'canafistula' (Peltophorum dubium) and 'ipê felpudo' (Zeyheria tuberculosa) (timber trees), and 'angico-branco' (Anadenanthera colubrina) and 'pau-jacaré' (Piptadenia gonoacantha) (N-fixing trees). Data were collected for 48 months. The results show differences among tree development, which was evaluated as growth in height and diameter, as well as sensitivity to insect and disease damage. The overall results show that the agrisilvicultural system allowed better tree development. The species with best performance in the two systems were capixingui, mutambo and canafístula. Ipê-felpudo and jequitibá-branco showed the worst results. The high variability among individuals of the same species indicates the possibility of high production advances with selective breeding of these species

Ação antioxidante de Coffea arabica cultivar mundo novo IAC 388-17 em diferentes graus de torra.

O café é uma das bebidas mais consumidas no Brasil e no mundo, e sua produção agrícola está intimamente ligada com a economia global. Neste caso, é fundamental o conhecimento profundo da sua relação com a saúde, bem-estar e a fisiologia dos seres humanos. Dentre as várias propriedades que o café pode apresentar, este trabalho visa estudar as propriedades antioxidantes em relação ao grau de torra. Utilizamos técnicas bioquímicas para investigar a proteção de amostras de café contra o dano oxidativo causado por espécies reativas de oxigênio às moléculas de DNA e lipídios in vitro. Foi investigada a ação protetora do café do cultivar Mundo Novo IAC 388-17. Os resultados de dano ao DNA e a proteção à peroxidação lipídica demonstraram que as amostras de café testadas apresentam propriedades antioxidantes semelhantes levando-se em consideração diferentes escalas de torra. Amostras de café classificadas de acordo com suas propriedades antioxidantes devem ser muito úteis para investigações sobre os possíveis benefícios à saúde dos antioxidantes presentes na bebid