Doses and methods of distribution of potassium chloride on soybean crop (Glycine max (L.) Merrill) in a red latosol, affecting soil salinity, grain production and chemical composition of leaves

The present work deal t wi th an experiment under field conditions and a laboratory test of soil incubation the objectives were as follows: a. to study effects on soybean grain product ion and leaf composition of increasing doses of potassium chloride applied into the soil through two methods of distribution; b. to observe chemical modifications in the soils incubated with increasing doses of potassium chloride; and, c. to correlate field effects with chemical alterations observed in the incubation test, The field experiment was carried out in a Red Latosol (Haplustox) with soybean cultivar UFV - 1. Potassium chloride was distributed through two methods: banded (5 cm below and 5 cm aside of the seed line) and broadcasted and plowed-down. Doses used were: 0; 50; 100 and 200 kg/ha of K2O. Foliar samples were taken at flowering stage. Incubation test were made in plastic bags with 2 kg of air dried fine soil, taken from the arable layer of the field experiment, with the following doses of KC1 p,a. : 0; 50; 100; 200; 400; 800; 1,600; 3.200; 6,400 and 12,800 kg/ha of K(2)0. In the conditions observed during the present work, results allowed the following conclusions: A response by soybean grain production for doses of potassium chloride, applied in both ways, banded or broadcasted, was not observed. Leaf analysis did not show treatment influence over the leaf contents for N, P, K, Ca, Mg, and CI, Potassium chloride salinity effects in both methods of distribution for all the tested closes were not observed.

Effects of tetrodotoxin and ion replacements on the short-circuit current induced by Escherichiacoli heat stable enterotoxin across small intestine of the gerbil (Gerbillus cheesmani)

The effects of mucosally added Escherichia coli heat stable enterotoxin (STa 30 ng ml-1) on the basal short-circuit current (Isc in µA cm-2) across stripped and unstripped sheets of jejuna and ilea taken from fed, starved (4 days, water ad lib) and undernourished (50% control food intake for 21 days) gerbil (Gerbillus cheesmani) were investigated. The effect of neurotoxin tetrodotoxin (TTX 10 µM) and the effects of replacing chloride by gluconate or the effects of removing bicarbonate from bathing buffers on the maximum increase in Isc induced by STa were also investigated. The maximum increase in Isc which resulted from the addition of STa were significantly higher in jejuna and ilea taken from starved and undernourished gerbils when compared with the fed control both using stripped and unstripped sheets. In the two regions of the small intestine taken from fed and starved animals TTX reduced the maximum increase in Isc induced by STa across unstripped sheets only. Moreover in jejuna and ilea taken from undernourished gerbils TTX reduced significantly the maximum increase in Isc induced by STa across stripped and unstripped sheets. Replacing chloride by gluconate decreased the maximum increase in Isc induced by STa across jejuna and ilea taken from undernourished gerbils only. Removing bicarbonates from bathing buffer decreased the maximum increase in Isc across the jejuna and ilea taken from starved and undernourished gerbils.

Potasssium chloride as a nutrient seed primer to enhance salt‑tolerance in maize

The objective of this work was to determine if KCl could be a useful nutrient primer for safe seed germination in maize crop under salt stress conditions. Seed priming was done using 50 mmol L‑1 of muriate of potash, and germination and seedling growth were evaluated after salt stress with NaCl up to 50 mmol L‑1. Another set of seeds was tested under the same salt stress conditions without priming. Under salinity stress, germination percentage, germination rate index, germination coefficient, and seedling vigor indexes were higher in primed seeds. In unprimed seeds, mean germination time increased, while the germination rate index and the fresh and dry matter mass decreased more sharply with salinity stress. The Na/K ratio was higher in unprimed seeds.

Effective diffusivity and convective mass transfer coefficient during the drying of bananas

In this article, a methodology is used for the simultaneous determination of the effective diffusivity and the convective mass transfer coefficient in porous solids, which can be considered as an infinite cylinder during drying. Two models are used for optimization and drying simulation: model 1 (constant volume and diffusivity, with equilibrium boundary condition), and model 2 (constant volume and diffusivity with convective boundary condition). Optimization algorithms based on the inverse method were coupled to the analytical solutions, and these solutions can be adjusted to experimental data of the drying kinetics. An application of optimization methodology was made to describe the drying kinetics of whole bananas, using experimental data available in the literature. The statistical indicators enable to affirm that the solution of diffusion equation with convective boundary condition generates results superior than those with the equilibrium boundary condition.

Magnesium chloride alone or in combination with diazepam fails to prevent hippocampal damage following transient forebrain ischemia

In the central nervous system, magnesium ion (Mg2+) acts as an endogenous modulator of N-methyl-D-aspartate (NMDA)-coupled calcium channels, and may play a major role in the pathomechanisms of ischemic brain damage. In the present study, we investigated the effects of magnesium chloride (MgCl2, 2.5, 5.0 or 7.5 mmol/kg), either alone or in combination with diazepam (DZ), on ischemia-induced hippocampal cell death. Male Wistar rats (250-300 g) were subjected to transient forebrain ischemia for 15 min using the 4-vessel occlusion model. MgCl2 was applied systemically (sc) in single (1x, 2 h post-ischemia) or multiple doses (4x, 1, 2, 24 and 48 h post-ischemia). DZ was always given twice, at 1 and 2 h post-ischemia. Thus, ischemia-subjected rats were assigned to one of the following treatments: vehicle (0.1 ml/kg, N = 34), DZ (10 mg/kg, N = 24), MgCl2 (2.5 mmol/kg, N = 10), MgCl2 (5.0 mmol/kg, N = 17), MgCl2 (7.5 mmol/kg, N = 9) or MgCl2 (5 mmol/kg) + DZ (10 mg/kg, N = 14). Seven days after ischemia the brains were analyzed histologically. Fifteen minutes of ischemia caused massive pyramidal cell loss in the subiculum (90.3%) and CA1 (88.4%) sectors of the hippocampus (P<0.0001, vehicle vs sham). Compared to the vehicle-treated group, all pharmacological treatments failed to attenuate the ischemia-induced death of both subiculum (lesion: 86.7-93.4%) and CA1 (lesion: 85.5-91.2%) pyramidal cells (P>0.05). Both DZ alone and DZ + MgCl2 reduced rectal temperature significantly (P<0.05). No animal death was observed after drug treatment. These data indicate that exogenous magnesium, when administered systemically post-ischemia even in different multiple dose schedules, alone or with diazepam, is not useful against the histopathological effects of transient global cerebral ischemia in rats.

Effects of hypertonic sodium chloride solution on the electrophysiologic alterations caused by bupivacaine in the dog heart

The effects of various hypertonic solutions on the intraventricular conduction, ventricular repolarization and the arrhythmias caused by the intravenous (iv) injection of bupivacaine (6.5 mg/kg) were studied in sodium pentobarbital-anesthetized mongrel dogs. Hypertonic solutions, given iv 5 min before bupivacaine, were 7.5% (w/v) NaCl, 5.4% (w/v) LiCl, 50% (w/v) glucose (2,400 mOsm/l, 5 ml/kg), or 20% (w/v) mannitol (1,200 mOsm/l, 10 ml/kg). Bupivacaine induced severe arrhythmias and ventricular conduction and repolarization disturbances, as reflected by significant increases in QRS complex duration, HV interval, IV interval and monophasic action potential duration, as well as severe hemodynamic impairment. Significant prevention against ventricular electrophysiologic and hemodynamic disturbances and ventricular arrhythmias was observed with 7.5% NaCl (percent increase in QRS complex duration: 164.4 ± 21.8% in the non-pretreated group vs 74.7 ± 14.1% in the pretreated group, P<0.05; percent increase in HV interval: 131.4 ± 16.1% in the non-pretreated group vs 58.2 ± 7.5% in the pretreated group, P<0.05; percent increase in monophasic action potential duration: 22.7 ± 6.8% in the non-pretreated group vs 9.8 ± 6.3% in the pretreated group, P<0.05; percent decrease in cardiac index: -46 ± 6% in the non-pretreated group vs -28 ± 5% in the pretreated group, P<0.05). The other three hypertonic solutions were ineffective. These findings suggest an involvement of sodium ions in the mechanism of hypertonic protection.

Protection of plasmid DNA by a Ginkgo biloba extract from the effects of stannous chloride and the action on the labeling of blood elements with technetium-99m

Ginkgo biloba extract (EGb) is a phytotherapeutic agent used for the treatment of ischemic and neurological disorders. Because the action of this important extract is not fully known, assays using different biological systems need to be performed. Red blood cells (RBC) are labeled with technetium-99m (Tc-99m) and used in nuclear medicine. The labeling depends on a reducing agent, usually stannous chloride (SnCl2). We assessed the effect of different concentrations of EGb on the labeling of blood constituents with Tc-99m, as sodium pertechnetate (3.7 MBq), and on the mobility of a plasmid DNA treated with SnCl2 (1.2 µg/ml) at room temperature. Blood was incubated with EGb before the addition of SnCl2 and Tc-99m. Plasma (P) and RBC were separated and precipitated with trichloroacetic acid, and soluble (SF-P and SF-RBC) and insoluble (IF-P and IF-RBC) fractions were isolated. The plasmid was incubated with Egb, SnCl2 or EGb plus SnCl2 and agarose gel electrophoresis was performed. The gel was stained with ethidium bromide and the DNA bands were visualized by fluorescence in an ultraviolet transilluminator system. EGb decreased the labeling of RBC, IF-P and IF-RBC. The supercoiled form of the plasmid was modified by treatment with SnCl2 and protected by 40 mg/ml EGb. The effect of EGb on the tested systems may be due to its chelating action with the stannous ions and/or pertechnetate or to the capability to generate reactive oxygen species that could oxidize the stannous ion.

Effect of chloride dialysate concentration on metabolic acidosis in aintenance hemodialysis patients

Hyperchloremia is one of the multiple etiologies of metabolic acidosis in hemodialysis (HD) patients. The aim of the present study was to determine the influence of chloride dialysate on metabolic acidosis control in this population. We enrolled 30 patients in maintenance HD program with a standard base excess (SBE) ≤2 mEq/L and urine output of less than 100 mL/24 h. The patients underwent dialysis three times per week with a chloride dialysate concentration of 111 mEq/L for 4 weeks, and thereafter with a chloride dialysate concentration of 107 mEq/L for the next 4 weeks. Arterial blood was drawn immediately before the second dialysis session of the week at the end of each phase, and the Stewart physicochemical approach was applied. The strong ion gap (SIG) decreased (from 7.5 ± 2.0 to 6.2 ± 1.9 mEq/L, P = 0.006) and the standard base excess (SBE) increased after the use of 107 mEq/L chloride dialysate (from -6.64 ± 1.7 to -4.73 ± 1.9 mEq/L, P < 0.0001). ∆SBE was inversely correlated with ∆SIG during the phases of the study (Pearson r = -0.684, P < 0.0001) and there was no correlation with ∆chloride. When we applied the Stewart model, we demonstrated that the lower concentration of chloride dialysate interfered with the control of metabolic acidosis in HD patients, surprisingly, through the effect on unmeasured anions.

Chloride concentration in red wines: influence of terroir and grape type

Red wines from different countries have been assessed in order to determine the influence of terroir and grape variety in their concentration of chloride. Chloride analysis was carried out by Laboratório de Bebidas de Origem Vegetal do Espírito Santo (Labeves), using the potentiometric method, in which the dosing is directly applied to the sample with an Ag/AgCl electrode. Data were collected to establish the level of chloride, as presented in the analysis reports issued by Labeves, and to serve as a wine categorization database, according to grape variety and country of origin. Australia and Argentina presented the highest levels of chloride and the wines made from the Syrah variety presented the highest concentration of such ion. We have, therefore, found that terroir and grape variety do have an influence over the concentration of chloride in red wines.

Comparison of methods for classification of the coefficient of variation in papaya

ABSTRACT The objective of this work was to study the distribution of values of the coefficient of variation (CV) in the experiments of papaya crop (Carica papaya L.) by proposing ranges to guide researchers in their evaluation for different characters in the field. The data used in this study were obtained by bibliographical review in Brazilian journals, dissertations and thesis. This study considered the following characters: diameter of the stalk, insertion height of the first fruit, plant height, number of fruits per plant, fruit biomass, fruit length, equatorial diameter of the fruit, pulp thickness, fruit firmness, soluble solids and internal cavity diameter, from which, value ranges were obtained for the CV values for each character, based on the methodology proposed by Garcia, Costa and by the standard classification of Pimentel-Gomes. The results obtained in this study indicated that ranges of CV values were different among various characters, presenting a large variation, which justifies the necessity of using specific evaluation range for each character. In addition, the use of classification ranges obtained from methodology of Costa is recommended.