Means and variances of some characters in base populations, with emphasis on grain yield in soybean.

The aim of this study was to evaluate in early generations of self-fertilization the potential of single, double and multiple crosses, as producers of base population for soybean breeding programs. The crosses were made involving eight parents with low coefficient of parentage between them. The experiment with the segregating populations was conducted in a completely randomized design with three replications. The results were subjected to analysis based on plot means and individual plants. For the characters number of days to flowering and to maturity, and plant height at flowering and at maturity, the means obtained with the F3 populations of single crosses, the F3 populations of double crosses and the F2 populations of multiple crosses were similar. The best results for grain yield per plant were obtained with the F3 populations of double crosses. ln general, no change was detected in the values of genetic variance of the segregating populations because of the number of parents used in the crosses

Métodos de inoculação para quantificação de resistência em soja a Fusarium solani f. sp. glycines, em casa-de-vegetação.

A síndrome da morte súbita (SMS), causada por Fusarium solani f. sp. glycines, tem se mostrado uma das mais importantes doenças da soja, devido aos prejuízos provocados e à dificuldade de controle. Este trabalho teve como objetivo selecionar os métodos de inoculação mais eficientes para a avaliação de resistência genética de genótipos de soja à SMS. Foram realizados dois experimentos em delineamento de blocos casualizados, sendo seis tratamentos e 12 repetições, no primeiro experimento, e seis tratamentos e 16 repetições, no segundo. Cada parcela foi constituída por um vaso contendo uma planta de soja da cultivar FT Estrela, altamente suscetível à SMS e outra planta de "Conquista", moderadamente resistente. As plantas foram avaliadas quanto à incidência e à severidade da SMS a cada três dias e durante 15 dias, com início no 15 dia após a emergência. A partir dos resultados, foi estimada a área abaixo da curva de progresso da doença (AACPD) para os tratamentos. As inoculações com grãos de sorgo e milho colonizados pelo patógeno foram mais eficientes em causar doença, no primeiro experimento, e com grãos de milho, no segundo. Entretanto, nos dois experimentos, apenas a inoculação com grãos de milho foi capaz de separar a reação das cultivares quanto à resistência à SMS, de acordo com o teste de Tukey (P<0,05). Desse modo, a inoculação com grãos de milho pode ser indicada para avaliações da reação de genótipos de soja à SMS, em casa-de-vegetação

Analysis of seismically-isolated two-block systems using a multi–rocking-body dynamic model

A novel multibody rocking model is developed to investigate the dynamic response of two stacked rigid blocks placed on a linear base isolation device. The model is used to investigate the dynamic response of a realistic statue-pedestal system subject to pulse-like ground motions. The analysis shows that, in general, base isolation increases the safety level of the rocking system. However, for large period pulses or small size blocks, the isolator can amplify the ground motion, resulting in a lower minimum overturning acceleration than for the nonisolated system. Further, the amplification or shock spectrum of a linear mass-dashpot-spring oscillator, was found to be the reciprocal of the minimum nondimensional overturning acceleration of the investigated rocking system. Novel rocking spectra are obtained by normalizing the frequency of the pulse by the frequency of the isolator. The analysis also demonstrates how the dynamic response of the two stacked blocks is equivalent to that of a single-block configuration coincident with the whole system assumed monolithic or the upper block alone, whichever is more slender

Monitoring DC anode current of a grounded-cathode photomultiplier tube

Abstract The Pierre Auger Observatories (PAO) for the highest energy cosmic rays will make use of both the Cherenkov and Air Fluorescence techniques. Surface Detectors (SD) and Fluorescence Detectors (FD) will have to operate in a desert-type environment during at least 15 years. In order to avoid dust deposition, due to electrostatics, and other practical inconveniences derived from biasing the cathode with a negative potential, the 15 000 PMTs of the FD will operate in the grounded cathode configuration. Despite the fact that the anodes will remain at high voltage with respect to ground, the DC anode current, which varies with background light, will have to be recorded. We have developed a current monitoring system based on a novel optocoupled feedback circuit that allows sensitive, linear, and temperature-independent measurements of the DC anode current. A distinctive feature of this circuit is that it uses optical coupling between passive components at high voltage and active components near the ground potential. This represents a substantial improvement over classical solutions which require the supply of power to an active circuit at high voltage. We report on the first tests performed with both active and passive biasing networks which demonstrate the validity of this new method

Lamination And Microstructuring Technology for a Bio-Cell Multiwell array

Microtechnology becomes a versatile tool for biological and biomedical applications. Microwells have been established long but remained non-intelligent up to now. Merging new fabrication techniques and handling concepts with microelectronics enables to realize intelligent microwells suitable for future improved cancer treatment. The described technology depicts the basis for the fabrication of a elecronically enhanced microwell. Thin aluminium sheets are structured by laser micro machining and laminated successively to obtain registration tolerances of the respective layers of 5..10\^A$\mu$m. The microwells lasermachined into the laminate are with 50..80\^A$\mu$m diameter, allowing to hold individual cells within the well. The individual process steps are described and results on the microstructuring are given.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing

Displacement-based design procedures for rigid block isolation

When subjected to earthquakes, many objects or structural elements behave like rocking rigid blocks. Computer servers, medical shelves, art objects, statues, and electrical transformers are frequently included in this category. Protection of these objects is an important task, considering that their value could be inestimable or their operation crucial during earthquakes; base isolation technology has been proven to be a viable option for this purpose. Initially, the dynamic model of a rocking rigid block placed on a base isolation device is reviewed. Then, two equivalent-static displacement-based procedures for designing the isolators for these types of objects are proposed, and the main steps are illustrated. The first procedure aims to determine isolator characteristics to prevent the initiation of rocking motion during the code-level earthquake event. The second procedure is aimed at designing isolators that allow a specified maximum rotation of the block during seismic events. The proposed procedures are validated by means of time-history analyses for a suite of spectrum-compatible accelerograms. The first displacement-based procedure appears particularly suitable for objects of small to medium size. The validation of the second procedure demonstrates that the equal displacement rule can be applied for this kind of systems, despite their softening. The results also indicate that the approach is particularly effective for medium to large structures/objects, if small oscillations are acceptable. The controlled rocking procedure offers a significant advantage by allowing for a reduction in the maximum displacement and period of the isolator, compared to situations where rocking motion must be prevented entirely

Solventless synthesis of quaterphenyls and terphenyls from chalcones and allylsulfones under Phase Transfer Catalysis conditions

Easily available chalcones and allyl sulfones along with cheap solid NaOH and polyethyleneglycol (PEG) 1000 have been used to directly generate the meta-terphenyl or quaterphenyl motifs under Phase Transfer Catalysis solventless conditions. The new approach provides an economic and environmentally friendly solution to removal of hazardous bases as well as organic solvents

Reaction of soybean cultivars to sudden death syndrome and disease scoring methods for screening resistance.

Soybean sudden death syndrome (SDS), caused by Fusarium solani f. sp. glycines, is found in more than 2.0 million hectares of soybean fields in Brazil. Identified for the first time during the 1981/82 crop season, in São Gotardo, Minas Gerais; it had already spread to 99 counties in Central and South Brazil by the 1999/2000 crop season, causing an estimated yield loss of US$ 53 million. Since no efficient control measure is yet available , it has been carried out through resistant cultivars. One of the difficulties in selecting resistant cultivars lies on the lack of a reliable source of resistance and of a screening method to distinguish the reactions among cultivars. The objective of this study was to define a criterium for differentiating soybean cultivars reaction to SDS and to find sources of resistance to the disease, based on leaf symptoms. The study included eight soybean cultivars in four replication and were carried out in a greenhouse in two experiments. Plants were inoculated by the colonized toothpick method and assessed 21 days after inoculation , using five different assessment criteria. Results showed that during the determination of the AP % (affected plants percentile ), which revealed the different reactions to SDS among soybean cultivars, the levels of chlorosis were not significantly different from those which took into consideration the incidence of leaf chlorosis or necrosis, regardless of the severity of leaf symptoms. The %AP and the scoring method using a scale of 1 to 5 were the best procedures to assess the reaction of soybean cultivars to SDS through leaf symptoms. Cultivar FT Estrela was used as a highly susceptible standard SDS (%AP = 96.32%). Genotypes PI 567734, PI 520733 and MG/BR 46 (Conquista) were the most resistant to SDS with AP % of 30.79%, 31.30% and 35.34%, respectively. They could be used as a source of SDS resistance in crosses in breeding programs

Acute anterior myocardial infarction: Streptokinase prevents ventricular thrombosis independently of its effect on infarct size

Left ventricular thrombosis (LVT) is a frequent complication after acute anterior myocardial infarction (AMI). The purpose of this study is to evaluate whether streptokinase (SK) therapy prevents LVT, and whether this effect is due to the preservation of left ventricular function or to the fibrinolytic action of the drug. Sixty-five patients who underwent a left ventricular angiography within 2 months after a first AMI were studied. Twenty-eight patients (SK group) received SK 1,500,000 U i.v. administered over 60 min within 6 h from the onset of symptoms. A lower incidence of LVT was found in the SK group (p = 0.0003). We divided patients into two classes according to the value of akinetic-dyskinetic area (AD): the first group with a lower value of AD, the second group with a higher value of AD. In both groups, a reduced incidence of LVT was associated with SK therapy (p = 0.014, p = 0.015, respectively). Early infusion of SK during AMI seems to prevent the development of LVT, with an effect partly independent from its action on infarct size for small to large myocardial infarction

Photoperiodism and genetic control of the long juvenile period in soybean: a review.

Soybean (Glycine max (L.) Merrill)is a short day plant that flowers when days are shorter than the maximum critical value, and this period is specific for each genotype. Soybean sensitivity to photoperiodism determines the limits of the sowing period for a latitude and hinders adaptation to wider ranges of latitude. The long juvenile period (LJP), which delays flowering under short day condictions, has been identified in soybean cultivars. The introduction of the LJP characteristic in soybean has made its cultivation possible in regions with latitudes lower than 15 o . Knowledge of the controlling genetic mechanisms of this characteristic can help in the development of soybean genotypes for lower latitudes with greater adaptation to sowing periods within the same latitude. Some conclusions about the genetic LJP control in soybean were reached from the present review: a) plants with LJP have a lower development rate for flowering, resulting in the lengthening of the vegetative period; b) the LJP characteristic has a direct influence on plant photoreceptivity and flowering induction; c) the genetic control of flowering time in short days is determined by a different and independent genetic system from that which determines long day flowering time; d) late flowering under short day conditions is a quantitative characteristic controlled by recessive genes, and it is believed that one to five main genes control flowering. Genotypes with a single pair of recessive alleles did not have LJP