The feasibility of using wind energy for rural populations lacking electric power in Brazil

In the wake of current global image involving environmental impacts, the use of wind power has had a remarkable growth in recent years as a technique for generating electricity. In fact, it is a source featuring strong dissemination of technology which provides decrease in costs and a greater access to low-income electricity. PROINFA (Incentive Program for Alternative Energy Sources) promotes a greater diffusion of new technologies for power generation, in particular wind-produced. Due to such a scenario on the exploitation of such energy source, current analysis discusses strategies for the development of domestic wind technology and the implications for electricity-lacking rural areas. Analysis shows a similar behavior between rural populations lacking electricity and the amount of potential energy available in the region. It is expected that this assay will contribute towards the establishment of public policies for wind-energy parks on rural farms in the North and Northeast regions of Brazil.

Electric consumption in SHSs in rural communities of brazil and Peru and recommendations for sizing

The lack of data records of electric power consumption of smallphotovoltaic home systems, independently of the method used for sizing them, drives to consider the demand as a constant. However, the existing data reveal the variability of the consumption due to the influences of some social, cultural and psychosocial aspects of the human groups. This paper presents records of consumption data obtainedfrom several solar home systems (SHSs) in Brazil and Peru, and it discusses about the Gamma distribution function that can express to a great extent the behaviour of the demand. By this analysis it was verified that `a lot of people consume little and few people consume a lot`. In that sense, a few recommendations for sizing procedures that can be useful in the implantation of extensive programmes of rural electrification by SHSs are presented. Copyright (c) 2007 John Wiley & Sons, Ltd.

Glandular trichomes on aerial and underground organs in Chrysolaena species (Vernonieae - Asteraceae): Structure, ultrastructure and chemical composition

Although the occurrence of glandular trichomes is frequently reported for aerial vegetative organs, many questions still remain opened about the presence of such trichomes in underground systems. Here, we present, for the first time, a comparative study concerning the structure, ultrastructure and chemical aspects of both, the aerial and underground glandular trichomes of two different Chrysolaena species, C obovata and C platensis. Glandular trichomes (GTs) were examined using LM, SEM, and TEM and also analyzed by GC-MS and HPLC coupled to UV/DAD and HR-ESI-MS (HPLC-UV-MS). In both aerial (leaf and bud) and underground (rhizophore) organs, the GTs are multicellular, biseriate and formed by five pairs of cells: a pair of support cells, a pair of basal cells, and three pairs of secreting cells. These secreting cells have, at the beginning of secretory process, abundance of smooth ER. The same classes of secondary metabolites are biosynthesized and stored in both aerial and underground GTs of C platensis and C obovata. These GTs from aerial and underground organs have similar cellular and sub-cellular anatomy, however the belowground trichomes show a higher diversity of compounds when compared to those from the leaves. We also demonstrate by means of HPLC-UV-DAD that the sesquiterpene lactones are located inside the trichomes and that hirsutinolides are not artifacts. (C) 2012 Elsevier GmbH. All rights reserved.

Anatomy and essential oils from aerial organs in three species of Aldama (Asteraceae-Heliantheae) that have a difficult delimitation

Recently, molecular analysis caused the South American Viguiera Kunth species to be transferred to Aldama La Llave. However, the circumscription has not been established for certain of the South American species, including Aldama filifolia (Sch. Bip. ex Baker) E. E. Schill. & Panero, A. linearifolia (Chodat) E. E. Schill. & Panero and A. trichophylla (Dusen) Magenta (comb. nov.), which had previously been treated as synonyms because of their high similarity. Therefore, the present study aimed to evaluate the anatomy of the aerial organs, and the yield and chemical composition of the essential oils from these three species, to determine the differences among them and thereby assist in species distinction. The anatomical analysis identified characteristics unique to each species, which are primarily related to the position and occurrence of secretory structures. Histochemical analysis demonstrated that the glandular trichomes and the canals secrete lipophilic substances, which are characterised by the presence of essential oils. The analysis of these essential oils identified monoterpenes as their major constituent and allowed for the recognition of chemical markers for each species. The anatomical and chemical characteristics identified by the present study confirmed that the studied samples belong to three distinct taxa.

Starch distribution in pear tree organs in relation to training systems, rootstocks and fruit quality

Starch is the main form in which plants store carbohydrates reserves, both in terms of amounts and distribution among different plant species. Carbohydrates are direct products of photosynthetic activity, and it is well know that yield efficiency and production are directly correlated to the amount of carbohydrates synthesized and how these are distributed among vegetative and reproductive organs. Nowadays, in pear trees, due to the modernization of orchards, through the introduction of new rootstocks and the development of new training systems, the understanding and the development of new approaches regarding the distribution and storage of carbohydrates, are required. The objective of this research work was to study the behavior of carbohydrate reserves, mainly starch, in different pear tree organs and tissues: i.e., fruits, leaves, woody organs, roots and flower buds, at different physiological stages during the season. Starch in fruit is accumulated at early stages, and reached a maximum concentration during the middle phase of fruit development; after that, its degradation begins with a rise in soluble carbohydrates. Moreover, relationships between fruit starch degradation and different fruit traits, soluble sugars and organic acids were established. In woody organs and roots, an interconversion between starch and soluble carbohydrates was observed during the dormancy period that confirms its main function in supporting the growth and development of new tissues during the following spring. Factors as training systems, rootstocks, types of bearing wood, and their position on the canopy, influenced the concentrations of starch and soluble carbohydrates at different sampling dates. Also, environmental conditions and cultural practices must be considered to better explain these results. Thus, a deeper understanding of the dynamics of carbohydrates reserves within the plant could provide relevant information to improve several management practices to increase crop yield efficiency.

[Radiation burden of organs in fluoroscopic studies]

Various conventional and modern fluoroscope units had been examined with an anthropomorphic phantom to determine the applied average organ doses. The aim of our investigation was to compare these doses with those normally delivered to the patients during a conventional X-ray examination of the thorax. As was to be expected, the doses resulting from conventional fluoroscopic units are much higher than the doses from modern units. As shown by means of our measurements, the efforts of advanced technology permit to reduce the dose rate up to a factor of 30. I.e., the doses resulting from modern fluoroscopic units are even smaller than the doses received during a conventional thoracic X-ray examination, what means a great improvement for this examination technic.

Three linked enzyme loci in fishes: implications in the evolution of vertebrate chromosomes.

A three-point linkage group comprised of loci coding for adenosine deaminase (ADA), glucose-6-phosphate dehydrogenase (G6PDH), and 6-phospho-gluconate dehydrogenase (6PGD) is described in fish of the genus Xiphophorus (Poeciliidae). The alleles at loci in this group were shown to assort independently from the alleles at three other loci--isocitrate dehydrogenase 1 and 2, and glyceraldehyde-3-phosphate dehydrogenase 1. Alleles at the latter three loci also assort independently from each other. Data were obtained by observing the segregation of electrophoretically variant alleles in reciprocal backcross hybrids derived from crosses between either X. helleri guentheri or X. h. strigatus and X. maculatus. The linkage component of chi2 was significant (less than 0.01) in all crosses, indicating that the linkage group is conserved in all populations of both species of Xiphophorus examined. While data from X. h. guentheri backcrosses indicate the linkage relationship ADA--6%--G6PDH--24%--6PGD, and ADA--29%--6PGD (30% when corrected for double crossovers), data from backcrosses involving strigatus, while supporting the same gene order, yielded significantly different recombination frequencies. The likelihood of the difference being due to an inversion could not be separated from the possibility of a sex effect on recombination in the present data. The linkage of 6PGD and G6PDH has been shown to exist in species of at least three classes of vertebrates, indicating the possibility of evolutionary conservation of this linkage.

LINKAGE RELATIONSHIPS AMONG PROTEIN-CODING LOCI IN FISHES OF THE GENUS XIPHOPHORUS

Inbred strains of three species of fishes of the genus Xiphophorus (platyfish and swordtails) were crossed to produce intra- and interspecific F(,1) hybrids, which were then backcrossed to one or both parental stocks. Backcross hybrids were used for the analysis of segregation and linkage of 33 protein-coding loci (whose products were visualized by starch gel electrophoresis) and a sex-linked pigment pattern gene. Segregation was Mendelian for all loci with the exception of one instance of segregation distortion. Six linkage groups of enzyme-coding loci were established: LG I, ADA --6%-- G(,6)PD --24%-- 6PGD; LG II, Est-2 --27%-- Est-3 --0%-- Est-5 --23%-- LDH-1 --16%-- MPI; LG III, AcPh --38%-- G(,3)PD-1 (GUK-2 --14%-- G(,3)PD-1 is also in LG III, but the position of GUK-2 with respect to AcPh has not yet been determined); LG IV, GPI-1 --41%-- IDH-1; LG V, Est-1 --38%-- MDH-2; and LG VI, P1P --7%-- UMPK-1 (P1P is a plasma protein, very probably transferrin).^ Sex-specific recombination appeared absent in LG II and LG IV locus pairs; significantly higher male recombination was demonstrated in LG I but significantly higher female recombination was detected in LG V. Only one significant population-specific difference in recombination was detected, in the G(,6)PD - 6PGD region of LG I; the notable absence of such effects implies close correspondence of the genomes of the species used in the study. Two cases of possible evolutionary conservation of linkage groups in fishes and mammals were described, involving the G(,6)PD - 6PGD linkage in LG I and the cluster of esterase loci in LG II. One clear case of divergence was observed, that of the linkage of ADA in LG I. It was estimated that a minimum of (TURN)50% of the Xiphophorus genome was marked by the loci studied. Therefore, the prior probability that a new locus will assort independently from the markers already established is estimated to be less than 0.5. A maximum of 21 of the 24 pairs of chromosomes could be marked with at least one locus.^ Only the two LG V loci showed a significant association with a postulated gene controlling the severity of a genetically controlled melanoma caused by abnormal proliferation of macromelanophore pigment pattern cells. The independence of melanotic severity from all other informative markers implies that one or at most a few major genes are involved in control of melanotic severity in this system. ^

Experimental study of electric breakdowns in liquid argon at centimeter scale

In this paper we present results on measurements of the dielectric strength of liquid argon near its boiling point and cathode-anode distances in the range of 0.1 mm to 40 mm with spherical cathode and plane anode. We show that at such distances the applied electric field at which breakdowns occur is as low as 40 kV/cm. Flash-overs across the ribbed dielectric of the high voltage feed-through are observed for a length of 300 mm starting from a voltage of 55 kV. These results contribute to set reference for the breakdown-free design of ionization detectors, such as Liquid Argon Time Projection Chambers (LAr TPC).

[Lung and pleural lesions before and after implementation of a national eradication program against enzootic pneumonia and actinobacillosis as well as changes of slaughter carcass organs in slaughter pigs in Switzerland].

In a representative cross-sectional study during 12 months of the years 2008/2009 in four abattoirs in Switzerland, lung and pleura lesions as well as lesions of slaughter carcasses and organs of 34 706 pigs were studied for frequency and type of macroscopic lesions. Of the 24276 examined pigs, 91.2% of the lungs, 94.4% of the heart and 95.5% of the livers showed no macroscopically visible lesions. Pigs that were produced for a label program had significantly less bronchopneumonia and pneumonia residuals, pleuritis and liver lesions due to echinococcosis. Pigs supervised by the Swiss Pig Health Service (SGD), showed significantly less bronchopneumonia and pneumonia residuals, diffuse pleuritis, pleuritis/pericarditis and milkspots compared to the non-SGD supervised farms. Thanks to the national eradication program for enzootic pneumonia (EP) and actinobacillosis, the health-status of lungs has been considerably improved and the prevalence of pleurisy decreased considerably. The results of this study indicate a good herd health in Swiss pig production.

Atmospheric electric measurement in the troposphere and stratosphere on the Atlantic Ocean during 1965 and 1969

One main point of the air electric investigations at the atlantic 1965 and 1969 was the record of the potential gradient in the troposphere with free and captive balloon ascents. The course of the field vs. altitude above the sea differs from that over land. A remarkable enlargement of the field strength occurs at the altitude of the passat inversion. The electric voltage between ionosphere and earth could be obtained by integrating the potential gradient over the altitude. Such computations have been made by balloon ascents simultaneous over the ocean and at Weissenau (South Germany), From 15 simultaneous measurements the average value of the potential of the ionosphere over the ocean is 214 kV and over South Germany 216 kV, that means very close together. Because of the small differences also between the single values it can be concluded that in generally the ionosphere potential has an equal value over these both places at one moment. From the potential of the ionosphere VI, the field strength E0 and the conductivity lamda o, both measured at the sea surface, the columnar resistance R could be derived to 2.4 x 10**17 Ohm x m**2. By correlation of the single values of the ionosphere potential with the potential gradient measured simultaneously at the surface of the sea a linear proportional relationship exists; it follows from this result, that R is nearly constant. The mean value of the air-earth current density over the ocean could be calculated by using the measured values of the small ion density with respect to the electrode effect prooved at the equator station. The current density was only 0.9 x 10**-12 A/m**2, which means, a three and a half times smaller value than estimated by Carnegie and accepted up to now. Therefore it seems to be necessary to correct the former calculations of the global current balance.

On the Electric Breakdown in Liquid Argon at Centimeter Scale

We present a study on the dependence of electric breakdown discharge properties on electrode geometry and the breakdown field in liquid argon near its boiling point. The measurements were performed with a spherical cathode and a planar anode at distances ranging from 0.1 mm to 10.0 mm. A detailed study of the time evolution of the breakdown volt-ampere characteristics was performed for the first time. It revealed a slow streamer development phase in the discharge. The results of a spectroscopic study of the visible light emission of the breakdowns complement the measurements. The light emission from the initial phase of the discharge is attributed to electro-luminescence of liquid argon following a current of drifting electrons. These results contribute to set benchmarks for breakdown-safe design of ionization detectors, such as Liquid Argon Time Projection Chambers (LAr TPC).