Observações preliminares sôbre a longevidade dos "Seedlings" de feijoeiro - Phaseolus vulgaris : em função das reservas cotiledonares

According previous studies about longevity in maize by ACCORSI e ADÂMOLI DE BARROS, (1961) the authors presents in this paper the results of work on longevity of seedlings of beans. Seeds were separated in three groups according their weight, as followings: small 80-120 mg; medium 130-140 mg and big 150-200 mg. The sowing of the seeds was made in pure sand and the seedlings were distributed in distil. water and in complete solution of Arnon and Hoagland. Each treatment was made in two replications with eight seedlings by treatment. At present time the following conclusions can be related: 1.°) - Eight days after germination, the cotiledones of all the seedlings started to fell down, fourteen days after, all cotiledones had fell down. 2.°) - Fifteen days after germination, the seedlings in nutritive solution showed better development than those in distil. water. Table I e II gives results. 3.°) - All seedlings in distil. water showed symptoms of N, Ca, Fe deficiencies. 4.°) - Twenty nine days after germination the seedlings in distil. water manifested exhaust trace, by falling of the leaves and death of some plants although the aplicai buds keep green. 5.°) - After thirty-one days the plants in nutritives solution was in better condition than those in distil. water, although some alteration aboved mentioned was observed. The causes of this alteration are being studied. 6.°) - In many plants in complet solution the seminal leaves showed clorosis initial and some with necrosis, although apical buds keeps in ativity. 7.°) - Symptoms of clorosis and necrosis in diferents stages were observed in all leaflet; these symptoms were more strong in the groups of little seed and medium seeds.

Dry matter production and nutrient exportation by pruned leaves and branches of apple trees

A trial was conducted on Latossol Vermelho Escuro Orto (Orthox) at Buri, State of São Paulo, Brazil. The material was collected from 'Ohio Beauty¹ and 'Brasil¹ apples trees grafted on 'Doucin'; the trees were 3-4, 4-5 and 6-7 years old. The authors concluded that at the dormant period differen ces were observed on the dry matter production as well on the nutrients exported by the leaves and branches of the two varieties. Branches exported higher amounts of P, Ca, B, Cu and Zn. Larger quantities of N, P and Mn were exported by the 1 eaves.

A comparative analysis of Cobb-Douglas model with additive and multiplicative error

This paper dis cusses the fitting of a Cobb-Doug las response curve Yi = αXβi, with additive error, Yi = αXβi + e i, instead of the usual multiplicative error Yi = αXβi (1 + e i). The estimation of the parameters A and B is discussed. An example is given with use of both types of error.

The importance of dietary calcium consumption in two species of semi-terrestrial grapsoid crabs

Calcium (Ca) is essential for crustaceans, due to calcium carbonate (CaCO3) deposition in the new exoskeleton to harden it. The purpose of this work was to study short term Ca balance in terms of dietary Ca ingestion in two phylogenetically related crabs (Superfamily Grapsoidea) showing different degrees of terrestrial adaptations: Sesarma rectum Randall, 1840 and Neohelice granulata (Dana, 1851). Dietary Ca ingestion was studied using purified diets with different Ca concentrations (0, 2.2 and 6.66 % Ca), together with measurements of Ca excretion and Ca hemolymph levels. The results showed that both crabs had the same response to foods containing different levels of Ca, with both species eating more of the high Ca diet. However, S. rectum consumed more per mg body mass at all Ca concentrations (6 mg.g-1 for S. rectum against 3 mg.g-1 for N. granulata). Both species excreted/egested Ca differently: S. rectum excreted Ca proportionally to ingestion, whereas N. granulata maintained constant faecal Ca output at all dietary Ca levels. Moreover, Ca hemolymph levels for crabs fed the different diets were independent of dietary Ca. In conclusion, both S. rectum and N. granulata seem to regulate the consumption of diets containing more Ca, which suggests a fine balance for Ca intake.

Periodic orbits near a heteroclinic loop formed by one dimensional orbit and a 2-dimensional manifold: application to the charged collinear 3-body problem

The paper is devoted to the study of a type of differential systems which appear usually in the study of some Hamiltonian systems with 2 degrees of freedom. We prove the existence of infinitely many periodic orbits on each negative energy level. All these periodic orbits pass near the total collision. Finally we apply these results to study the existence of periodic orbits in the charged collinear 3–body problem.

Preferential assembly of epithelial sodium channel (ENaC) subunits in Xenopus oocytes: role of furin-mediated endogenous proteolysis.

The epithelial sodium channel (ENaC) is preferentially assembled into heteromeric alphabetagamma complexes. The alpha and gamma (not beta) subunits undergo proteolytic cleavage by endogenous furin-like activity correlating with increased ENaC function. We identified full-length subunits and their fragments at the cell surface, as well as in the intracellular pool, for all homo- and heteromeric combinations (alpha, beta, gamma, alphabeta, alphagamma, betagamma, and alphabetagamma). We assayed corresponding channel function as amiloride-sensitive sodium transport (I(Na)). We varied furin-mediated proteolysis by mutating the P1 site in alpha and/or gamma subunit furin consensus cleavage sites (alpha(mut) and gamma(mut)). Our findings were as follows. (i) The beta subunit alone is not transported to the cell surface nor cleaved upon assembly with the alpha and/or gamma subunits. (ii) The alpha subunit alone (or in combination with beta and/or gamma) is efficiently transported to the cell surface; a surface-expressed 65-kDa alpha ENaC fragment is undetected in alpha(mut)betagamma, and I(Na) is decreased by 60%. (iii) The gamma subunit alone does not appear at the cell surface; gamma co-expressed with alpha reaches the surface but is not detectably cleaved; and gamma in alphabetagamma complexes appears mainly as a 76-kDa species in the surface pool. Although basal I(Na) of alphabetagamma(mut) was similar to alphabetagamma, gamma(mut) was not detectably cleaved at the cell surface. Thus, furin-mediated cleavage is not essential for participation of alpha and gamma in alphabetagamma heteromers. Basal I(Na) is reduced by preventing furin-mediated cleavage of the alpha, but not gamma, subunits. Residual current in the absence of furin-mediated proteolysis may be due to non-furin endogenous proteases.

Tegumental Ca-stimulated adenosine triphosphatase activity in adult Schistosoma mansoni worms

A Ca-stimulated ATPase activity (pH 9.5) associated with the tegumental membrane enriched (TME) fraction of Schistosoma mansoni adults was partially inhibited by NAP-taurine or by increasing concentrations of chlorpromazine; endogenous calmodulin was found associated with the TME fraction. A similar activity (pH 8.6) was histochemically visualized whithin the tegument of fixed worms on the cytoplasmic leaflet of both the doubel surface membrane and the basement membrane; this reaction was inhibited by 1 µM chloropromazine and it was also observed on the inner side of double membrane vesicles present in the TME fraction. No ATPase activity could be seen at alkaline pH with added Mg or Na/K ions. Without ATP, the addition of external Ca to the fixed worms induced the appearance of lead precipitates on the tegumental discoid bodies; this reaction was inhibited by molybdate and not by chlorpromazine. The intrategumentary regulation of calcium by the systems described and the possible use of phenothiazines against schistosimes are discussed.

The clinical application of converting enzyme inhibitors.

Chronic blockade of the renin angiotensin system became possible when orally active inhibitors of angiotensin converting enzyme, the enzyme which catalyzes the transformation of angiotensin I into angiotensin II, were synthetized. Two compounds, captopril and enalapril, have been investigated in clinical studies. The decrease of the pressor response to exogenous angiotensin I and of the circulating levels of angiotensin II following administration of these inhibitors has been demonstrated to be directly related to the degree of suppression of plasma angiotensin converting enzyme activity. These inhibitors have been shown to normalize blood pressure alone in some hypertensive patients whereas in many others, satisfactory blood pressure control can be achieved only after the addition of a diuretic. Captopril and enalapril also markedly improve cardiac function of patients with chronic congestive heart failure. Chronic blockade of the renin angiotensin system has therefore provided an interesting new approach to the treatment of clinical hypertension and heart failure.

The Impacts of Temporary and Anticipated Tourism Spending.

Part of the local economic impact of a major sporting event comes from the associated temporary tourism expenditures. Typically demand-driven Input-Output (IO) methods are used to quantify the impacts of such expenditures. However, IO modelling has specific weaknesses when measuring temporary tourism impacts; particular problems lie in its treatment of factor supplies and its lack of dynamics. Recent work argues that Computable General Equilibrium (CGE) analysis is more appropriate and this has been widely applied. Neglected in this literature however is an understanding of the role that behavioural characteristics and factor supply assumptions play in determining the economic impact of tourist expenditures, particularly where expenditures are temporary (i.e. of limited duration) and anticipated (i.e. known in advance). This paper uses a CGE model for Scotland in which agents can have myopic- or forward-looking behaviours and shows how these alternative specifications affect the timing and scale of the economic impacts from anticipated and temporary tourism expenditure. The tourism shock analysed is of a scale expected for the Commonwealth Games to be held in Glasgow in 2014. The model shows how “pre-shock” and “legacy” effects – impacts before and after the shock – arise and their quantitative importance. Using the forward-looking model the paper calculates the optimal degree of pre-announcement.

Tracking of Stepwise Ablation of Persistent Atrial Fibrillation using Synchronization of nearby Electrogams

Intracardiac organization indices such as atrial fibril- lation (AF) cycle length (AFCL) have been used to track the efficiency of stepwise catheter ablation (step-CA) of long-standing persistent AF (pers-AF), however, with lim- ited success. The timing between nearby bipolar intracar- diac electrograms (EGMs) reflects the spatial dynamics of wavelets during AF. The extent of synchronization between EGMs is an indirect measure of AF spatial organization. The synchronization between nearby EGMs during step- CA of pers-AF was evaluated using new indices based on the cross-correlation. The first one (spar(W)) quantifies the sparseness of the cross-correlation of local activation times. The second one (OI(W)) reflects the local concen- tration around the largest peak of the cross-correlation. By computing their relative evolution during step-CA until AF termination (AF-term), we found that OI(W) appeared su- perior to AFCL and spar(W) to track the effect of step-CA "en route" to AF-term.

Geochemistry of highly acidic mine water following disposal into a natural lake with carbonate bedrock

Acid mine drainage (AMD) from the Zn-Pb(-Ag-Bi-Cu) deposit of Cerro de Pasco (Central Peru) and waste water from a Cu-extraction plant has been discharged since 1981 into Lake Yanamate, a natural lake with carbonate bedrock. The lake has developed a highly acidic pH of similar to 1. Mean lake water chemistry was characterized by 16,775 mg/L acidity as CaCO(3), 4330 mg/L Fe and 29,250 mg/L SO(4). Mean trace element concentrations were 86.8 mg/L Cu, 493 mg/L Zn, 2.9 mg/L Pb and 48 mg/L As, which did not differ greatly from the discharged AMD. Most elements showed increasing concentrations from the surface to the lake bottom at a maximal depth of 41 m (e.g. from 3581 to 5433 mg/L Fe and 25,609 to 35,959 mg/L SO(4)). The variations in the H and 0 isotope compositions and the element concentrations within the upper 10 m of the water column suggest mixing with recently discharged AMD, shallow groundwater and precipitation waters. Below 15 m a stagnant zone had developed. Gypsum (saturation index, SI similar to 0.25) and anglesite (SI similar to 0.1) were in equilibrium with lake water. Jarosite was oversaturated (SI similar to 1.7) in the upper part of the water column, resulting in downward settling and re-dissolution in the lower part of the water column (SI similar to -0.7). Accordingly, jarosite was only found in sediments from less than 7 m water depth. At the lake bottom, a layer of gel-like material (similar to 90 wt.% water) of pH similar to 1 with a total organic C content of up to 4.40 wet wt.% originated from the kerosene discharge of the Cu-extraction plant and had contaminant element concentrations similar to the lake water. Below the organic layer followed a layer of gypsum with pH 1.5, which overlaid the dissolving carbonate sediments of pH 5.3-7. In these two layers the contaminant elements were enriched compared to lake water in the sequence As < Pb approximate to Cu < Cd < Zn = Mn with increasing depth. This sequence of enrichment was explained by the following processes: (i) adsorption of As on Fe-hydroxides coating plant roots at low pH (up to 3326 mg/kg As), (ii) adsorption at increasing pH near the gypsum/calcite boundary (up to 1812 mg/kg Pb, 2531 mg/kg Cu. and 36 mg/kg Cd), and (iii) precipitation of carbonates (up to 5177 mg/kg Zn and 810 mg/kg Mn: all data corrected to a wet base). The infiltration rate was approximately equal to the discharge rate, thus gypsum and hydroxide precipitation had not resulted in complete clogging of the lake bedrocks. (C) 2010 Elsevier Ltd. All rights reserved.

Prospective validation of the Pulmonary Embolism Severity Index. A clinical prognostic model for pulmonary embolism

Practice guidelines recommend outpatient care for selected patients with non-massive pulmonary embolism (PE), but fail to specify how these low-risk patients should be identified. Using data from U.S. patients, we previously derived the Pulmonary Embolism Severity Index (PESI), a prediction rule that risk stratifies patients with PE. We sought to validate the PESI in a European patient cohort. We prospectively validated the PESI in patients with PE diagnosed at six emergency departments in three European countries. We used baseline data for the rule's 11 prognostic variables to stratify patients into five risk classes (I-V) of increasing probability of mortality. The outcome was overall mortality at 90 days after presentation. To assess the accuracy of the PESI to predict mortality, we estimated the sensitivity, specificity, and predictive values for low- (risk classes I/II) versus higher-risk patients (risk classes III-V), and the discriminatory power using the area under the receiver operating characteristic (ROC) curve. Among 357 patients with PE, overall mortality was 5.9%, ranging from 0% in class I to 17.9% in class V. The 186 (52%) low-risk patients had an overall mortality of 1.1% (95% confidence interval [CI]: 0.1-3.8%) compared to 11.1% (95% CI: 6.8-16.8%) in the 171 (48%) higher-risk patients. The PESI had a high sensitivity (91%, 95% CI: 71-97%) and a negative predictive value (99%, 95% CI: 96-100%) for predicting mortality. The area under the ROC curve was 0.78 (95% CI: 0.70-0.86). The PESI reliably identifies patients with PE who are at low risk of death and who are potential candidates for outpatient care. The PESI may help physicians make more rational decisions about hospitalization for patients with PE.

Projecte pilot d'innovació docent de l'assignatura Estructura de Computadors I

L'objectiu del projecte ha estat la millora de la qualitat docent de l'assignatura Estructura de Computadors I, impartida a la Facultat d'Informàtica de Barcelona (UPC) dins els estudis d'Enginyeria Informàtica, Enginyeria Tècnica en Informàtica de Sistemes i Enginyeria Tècnica en Informàtica de Gestió. S'ha treballat en quatre línies d'actuació: (i) aplicació de tècniques d'aprenentatge actiu a les classes; (ii) aplicació de tècniques d'aprenentage cooperatiu no presencials; (iii) implantació de noves TIC i adaptació de les ja emprades per tal d'habilitar mecanismes d'autoavaluació i de realimentació de la informació referent a l'avaluació; i (iv) difusió de les experiències derivades de les diferents actuacions. Referent a les dues primeres mesures s'avalua l'impacte de metodologies docents que afavoreixen l'aprenentatge actiu tant de forma presencial com no presencial, obtenint-se clares millores en el rendiment respecte a altres metodologies utilitzades anteriorment enfocades a la realització de classes del tipus magistral, en què únicament es posa a l'abast dels alumnes la documentació de l'assignatura per a què puguin treballar de forma responsable. Les noves metodologies fan especial èmfasi en el treball en grup a classe i la compartició de les experiències fora de classe a través de fòrums de participació. La mesura que ha requerit més esforç en aquest projecte és la tercera, amb el desenvolupament d'un entorn d'interfície web orientat a la correcció automàtica de programes escrits en llenguatge assemblador. Aquest entorn permet l'autoavaluació per part dels alumnes dels exercicis realitzats a l'assignatura, amb obtenció d'informació detallada sobre les errades comeses. El treball realitzat dins d'aquest projecte s'ha publicat en congressos rellevants en l'àrea docent tant a nivell estatal com internacional. El codi font de l'entorn esmentat anteriorment es posa a disposició pública a través d'un enllaç a la web.

The fou2 mutation in the major vacuolar cation channel TPC1 confers tolerance to inhibitory luminal calcium.

The SV channel encoded by the TPC1 gene represents a Ca(2+)- and voltage-dependent vacuolar cation channel. Point mutation D454N within TPC1, named fou2 for fatty acid oxygenation upregulated 2, results in increased synthesis of the stress hormone jasmonate. As wounding causes Ca2+ signals and cytosolic Ca2+ is required for SV channel function, we here studied the Ca(2+)-dependent properties of this major vacuolar cation channel with Arabidopsis thaliana mesophyll vacuoles. In patch clamp measurements, wild-type and fou2 SV channels did not exhibit differences in cytosolic Ca2+ sensitivity and Ca2+ impermeability. K+ fluxes through wild-type TPC1 were reduced or even completely faded away when vacuolar Ca2+ reached the 0.1-mm level. The fou2 protein under these conditions, however, remained active. Thus, D454N seems to be part of a luminal Ca2+ recognition site. Thereby the SV channel mutant gains tolerance towards elevated luminal Ca2+. A three-fold higher vacuolar Ca/K ratio in the fou2 mutant relative to wild-type plants seems to indicate that fou2 can accumulate higher levels of vacuolar Ca(2+) before SV channel activity vanishes and K(+) homeostasis is impaired. In response to wounding fou2 plants might thus elicit strong vacuole-derived cytosolic Ca2+ signals resulting in overproduction of jasmonate.

Epidemiology of Chagas disease in Ecuador. A brief review

Chagas disease is a complex public health problem that has been underestimated in Ecuador. Here we review the relevant published information, and present unpublished and new data that help to understand the current Chagas disease epidemiological situation and its evolution in the country. Three main characteristics have been identified: (i) persistence of Trypanosoma cruzi transmission in already known foci; (ii) a marked endemicity in some urban areas of Guayaquil; and (iii) the transformation of new Amazon foci into truly endemic areas. The situation in other suspect areas remains uncertain. Five Triatominae species have been implicated in the transmission of T. cruzi to people in Ecuador (Triatoma dimidiata, Rhodnius ecuadoriensis, R. pictipes, R. robustus and Panstrongylus geniculatus), but some others may also play a role in some areas (P. rufotuberculatus, P. howardi, T. carrioni and P. chinai). Other Triatominae reported seem to have little or no epidemiological relevance (T. venosa, T. dispar, Eratyrus mucronatus, E. cuspidatus, P. lignarius and Cavernicola pilosa). High frequency of acute cases and severe chronic disease has been observed. Although cardiomyopathy is more frequent, serious digestive disease is also present. It is estimated that around 120,000-200,000 people may be infected. 2.2 to 3.8 million people are estimated to live under transmission risk conditions.