scholarly journals Physical, chemical and mineralogical attributes of a representative group of soils from the Eastern Amazon, Brazil

2018 ◽  
Author(s):  
Edna Santos de Souza ◽  
Antonio Rodrigues Fernandes ◽  
Anderson Martins de Souza Braz ◽  
Fábio Júnior de Oliveira ◽  
Luís Reynaldo Ferracciú Alleoni ◽  
...  
Keyword(s):  
Descriptive Analysis ◽  
Sustainable Use ◽  
Ammonium Oxalate ◽  
Principal Component ◽  
Sodium Dithionite ◽  
Physical Chemical ◽  
Low Concentrations ◽  
High Concentrations ◽  
And Cluster Analysis ◽  
Al Oxide

Abstract. Amazonian soils are heterogeneous. However, few studies have been carried out in the Amazon, mainly because of its considerable size, which complicates the collection of data and the ability to plan for the sustainable use of natural resources. In this study, the physical, chemical and mineralogical attributes of soils in the state of Pará, Brazil, were characterized by examining particle size, fertility, silicon (Si) extracted by sodium hydroxide (NaOH), and iron (Fe), aluminum (Al), and manganese (Mn) extracted by sulfuric acid (H2SO4), sodium dithionite-citrate-bicarbonate and ammonium oxalate + oxalic acid. Descriptive analysis, multivariate principal component analysis and cluster analysis were carried out. The soils had low concentrations of bioavailable P, Ca2+, Mg2+ and K+ and high concentrations of Al3+ and Si and Al oxide contents were higher in Cambisols. Contents of Fe and Mn oxides were higher in both Cambisols and Nitosols, which are rich in oxidic minerals. Multivariate analysis indicated an association between the content of organic carbon and the pH, P, Ca, Mg and K contents. An additional association was observed between clay, potential acidity and the Fe and Al oxide contents.

scholarly journals Physical, chemical, and mineralogical attributes of a representative group of soils from the eastern Amazon region in Brazil

SOIL ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 195-212 ◽  
Author(s):  
Edna Santos de Souza ◽  
Antonio Rodrigues Fernandes ◽  
Anderson Martins De Souza Braz ◽  
Fábio Júnior de Oliveira ◽  
Luís Reynaldo Ferracciú Alleoni ◽  
...  
Keyword(s):  
Descriptive Analysis ◽  
Sustainable Use ◽  
Ammonium Oxalate ◽  
Principal Component ◽  
Organic Carbon Content ◽  
Physical Chemical ◽  
Low Concentrations ◽  
High Concentrations ◽  
And Cluster Analysis ◽  
Al Oxide

Abstract. Amazonian soils are heterogeneous. However, few studies have been carried out in the Amazon, mainly because of its considerable size, which complicates the collection of data and the ability to plan for the sustainable use of natural resources. In this study, the physical, chemical, and mineralogical attributes of soils in the state of Pará, Brazil, were characterized by examining the particle size, fertility, silicon extracted by sodium hydroxide, iron, and aluminum, and manganese extracted by sulfuric acid, sodium citrate-bicarbonate-dithionite, and ammonium oxalate + oxalic acid. A descriptive analysis, multivariate principal component analysis, and cluster analysis were performed. The soils had low concentrations of bioavailable P, Ca2+, Mg2+, and K and had high concentrations of Al3+, Si, and Al oxide in the Cambisols. Concentrations of Fe and Mn oxides were higher in both the Cambisols and Nitosols, which are rich in oxidic minerals. The multivariate analysis indicated an association between the organic carbon content and pH, P, Ca, Mg, and K concentrations. An additional association was observed between clay, potential acidity, and the Fe and Al oxide concentrations.

Limnology of oligotrophic dune lakes at Cape Flattery, North Queensland

1988 ◽  
Vol 39 (4) ◽  
pp. 535 ◽  
Author(s):  
PR Hawkins ◽  
LE Taplin ◽  
LJ Duivenvoorden ◽  
F Scott
Keyword(s):  
Aquatic Macrophytes ◽  
Principal Component ◽  
Freshwater Turtles ◽  
Clear Water ◽  
Physical Chemical ◽  
Low Concentrations ◽  
Low Diversity ◽  
Dune Lakes ◽  
Crocodylus Porosus ◽  
Local Water

Physical, chemical and biotic attributes of 16 lakes and ponds in the siliceous dunefields of Cape Flattery, in the humid tropics of Australia, have been investigated. The dune lakes are similar to those of dunefields in south-eastern Queensland, with very low to low conductivity (62-338 �S cm-1), low pH (3.9-6.8), and low to high humic content (gilvin 0.0-31.0 g440 m-1). These lakes are apparently not perched above the local water table. The ionic compositions of all lakes were very similar, with NaCl predominating and with very low concentrations of Mg, Ca, K, and SO4. Bicarbonate was absent or negligible in most lakes. The oligotrophic lakes are characterized by a desmid-diatom limnetic plankton of moderate diversity (12-35 species per lake). Of 144 taxa of phytoplankton recognized, 58% were desmids and 15% diatoms. The zooplankton was of low diversity and dominated by Calamoecia ultima. Twenty-nine species of aquatic macrophytes and 11 species of fish were recorded. Freshwater turtles (possibly Chelodina rugosa Ogilby), and the estuarine crocodile, Crocodylus porosus Schneider, were recorded from some lakes. Principal component analysis of chemical data distinguished three groups of lakes: a series of humic-stained ponds and lakes, a group of clear-water lakes with little or no humic staining, and a former barrier lagoon. Cluster analysis of the phytoplankton flora consistently segregated the clear-water lakes from humic-stained lakes but, in general, concordance of chemical, physiographic and biotic characteristics was poor. Existing classification schemes for Australian dune lakes, based on similar sets of physiographic, chemical and biotic data, do not cater well for the Cape Flattery lakes. A more useful classification may derive from consideration of the hydrological processes influencing their water balance and chemical characteristics.

Segmenting the organic food market in Lebanon: an application of k-means cluster analysis

2017 ◽  
Vol 119 (7) ◽  
pp. 1423-1441 ◽  
Author(s):  
Malak Tleis ◽  
Roberta Callieris ◽  
Rocco Roma
Keyword(s):  
Cluster Analysis ◽  
Descriptive Analysis ◽  
Organic Food ◽  
Principal Component ◽  
Marketing Strategies ◽  
Content Type ◽  
Organic Products ◽  
Food Market ◽  
Promotional Strategies ◽  
And Cluster Analysis

Purpose The purpose of this paper is to discover profiles of organic food consumers in Lebanon by performing a market segmentation based on lifestyle and attitude variables and thus be able to propose appropriate marketing strategies for each market segment. Design/methodology/approach A survey, based on the use of closed-ended questionnaire, was addressed to 320 organic food consumers in the capital Beirut, in February and March 2014. Descriptive analysis, principal component analysis and cluster analysis (k-means method) were performed upon collected data. Findings Four clusters were obtained and labelled based on psychographic characteristics and willingness to pay for the most purchased organic products. “Localist” and “Health conscious” clusters were the largest proportion of the selected sample, thus these were the most critical to be addressed by specific marketing strategies, emphasising the combination of local and organic food and the healthy properties of organic products. “Rational” and “Irregular” cluster were relatively small groups, addressed by pricing and promotional strategies. Originality/value This is the first study attempting to segment organic food consumers into different categories in a developing country as Lebanon.

scholarly journals Evaluation of the Water Quality of the Vaca Brava Stream: contributions to Environmental Sciences and Health

2018 ◽  
Vol 45 (1) ◽  
Author(s):  
Patrícia Regina Silva ◽  
Júlio Cezar Rubin de Rubin
Keyword(s):  
Principal Component ◽  
Longitudinal Axis ◽  
Human Occupation ◽  
Land Occupation ◽  
Negative Results ◽  
Physical Chemical ◽  
Microbiological Characteristics ◽  
Sampling Points ◽  
High Concentrations ◽  
Small Industries

The process of land occupation in Goiânia demonstrates that, owing to its accelerated populational growth, the city reproduced all the socioenvironmental contradictions of a big metropolis. This study reports an evaluation of the physical, chemical and microbiological characteristics of the Vaca Brava Stream, with a temporal and spatial analyses of its limnological characteristics. The samples collecting was carried out in eight points along the longitudinal axis of the Vaca Brava Stream between June 2015 and May 2016, encompassing the rainy and dry seasons. Twenty-seven physical-chemical and biological parameters were monitored. For the results a principal component analysis (PCA) was performed, with the t-test to verify differences between the collecting periods (dry and rainy). In a general manner, the results indicated waters with low values of turbidity, nutrients, DBO5 and Chlorophyll-a. However, there were exceptions, as the high concentrations of total phosphor, orthophosphate, total nitrogen (Kjeldahl), and ammoniacal nitrogen, recorded in some places during the dry season. Low concentrations of dissolved oxygen were also frequent in the study area. The results point to an expected seasonality which may be related to a larger contribution of polluting sources. The protection of the Vaca Brava Stream headwaters contributes to better values in the sampling points located upstream, most probably owing to the fact of the VBMP. The disorderly human occupation is reflected in the higher housing concentration (especially vertical) in the intermediary parts of the Vaca Brava Stream, being coherent with the more negative results expressed in this stretch of the stream. Among all sampling points, the most relevant for the majority of alterations is the Point 5, which might be reflecting the effluent loads coming from sewers, commerce, and small industries as channeled form or surface runoff in the rainy season. Avaliação da Qualidade da Água do Córrego Vaca Brava: contribuições para Ciências Ambientais e Saúde O processo de ocupação do solo em Goiânia demostra que, devido ao seu acelerado crescimento populacional, a cidade reproduziu todas as contradições socioambientais de uma grande metrópole. Esse estudo relata uma avaliação das características físicas, químicas e microbiológicas do córrego Vaca Brava, com uma análise da variação temporal e espacial das suas características limnológicas. A coleta das amostras foi realizada em oito pontos no eixo longitudinal do córrego Vaca Brava, entre junho de 2015 e maio de 2016, abrangendo as estações de chuva e seca. Foram monitorados 27 parâmetros físico-químicos e biológicos. Para os resultados foi realizada uma análise de componentes principais (PCA), com o teste t para verificar a existência de diferença entre os períodos de coleta (seca e chuva). De maneira geral, os resultados indicaram águas com baixos valores de turbidez, nutrientes, DBO5 e Clorofila-a. No entanto, ocorreram exceções, como as elevadas concentrações de fósforo total, ortofosfato, nitrogênio total (Kjeldahl) e nitrogênio amoniacal registradas em alguns locais no período de seca. Baixas concentrações de oxigênio dissolvido também foram frequentes na área de estudo. Os resultados apontam para uma sazonalidade esperada, que podem estar correlacionados a uma maior contribuição de fontes poluentes. A proteção das cabeceiras do córrego Vaca Brava contribui para valores amenos nos pontos amostrais mais à jusante, muito provavelmente devido ao fato da criação do PMVB. A ocupação humana desordenada se reflete na maior concentração de residências (especialmente verticais) nas partes intermediárias do córrego Vaca Brava, sendo coerente com os resultados mais negativamente expressivos nesse trecho do córrego. Dentre todos os pontos amostrais, o de maior relevância para a maioria das alterações é o Ponto 5, que pode estar refletindo cargas de efluentes advindas de esgotos, comércio e pequenas indústrias, seja de forma canalizada ou por enxurradas na estação chuvosa.

Neutrophil Elastase Potentiates Cathepsin G-lnduced Platelet Activation

1992 ◽  
Vol 68 (05) ◽  
pp. 570-576 ◽  
Author(s):  
Mary A Selak
Keyword(s):  
Neutrophil Elastase ◽  
Cell Activation ◽  
Thromboxane A2 ◽  
Creatine Phosphate ◽  
Dense Granule ◽  
Cathepsin G ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Low Concentrations ◽  
High Concentrations

SummaryWe have previously demonstrated that human neutrophil cathepsin G is a strong platelet agonist that binds to a specific receptor. This work describes the effect of neutrophil elastase on cathepsin G-induced platelet responses. While platelets were not activated by high concentrations of neutrophil elastase by itself, elastase enhanced aggregation, secretion and calcium mobilization induced by low concentrations of cathepsin G. Platelet aggregation and secretion were potentiated in a concentration-dependent manner by neutrophil elastase with maximal responses observable at 200 nM. Enhancement was observed when elastase was preincubated with platelets for time intervals of 10–60 s prior to addition of a low concentration of cathepsin G and required catalytically-active elastase since phenylmethanesulphonyl fluoride-inhibited enzyme failed to potentiate cell activation. Neutrophil elastase potentiation of platelet responses induced by low concentrations of cathepsin G was markedly inhibited by creatine phosphate/creatine phosphokinase and/or indomethacin, indicating that the synergism between elastase and cathepsin G required the participation of ADP and thromboxane A2. On the other hand, platelet responses were not attenuated by the PAF antagonist BN 52021, signifying that PAF-acether did not play a role in elastase potentiation. At higher concentrations porcine pancreatic elastase exhibits similar effects to neutrophil elastase, demonstrating that the effect of elastase was not unique to the neutrophil protease. While neutrophil elastase failed to alter the ability of cathepsin G to hydrolyze a synthetic chromogenic substrate, preincubation of platelets with elastase increased the apparent affinity of cathepsin G binding to platelets. In contrast to their effect on cathepsin G-induced platelet responses, neither neutrophil nor pancreatic elasatse potentiated aggregation or dense granule release initiated by ADP, PAF-acether, arachidonic acid or U46619, a thromboxane A2 mimetic. Moreover, unlike its effect on cathepsin G, neutrophil elastase inhibited thrombin-induced responses. The current observations demonstrate that elastase can potentiate platelet responses mediated by low concentrations of cathepsin G, suggesting that both enzymes may function synergistically to activate platelets under conditions where neutrophil degranulation occurs.

In Vitro Effects of Ethanol on Rabbit Platelet Aggregation, Secretion of Granule Contents, and Cyclic AMP Levels in the Presence of Prostacyclin

1989 ◽  
Vol 61 (02) ◽  
pp. 254-258 ◽  
Author(s):  
Margaret L Rand ◽  
Peter L Gross ◽  
Donna M Jakowec ◽  
Marian A Packham ◽  
J Fraser Mustard
Keyword(s):  
Cyclic Amp ◽  
Inhibitory Effect ◽  
Rabbit Platelet ◽  
Inhibitory Effects ◽  
Low Concentrations ◽  
Rabbit Platelets ◽  
High Concentrations ◽  
In Vitro Effects ◽  
Aggregation Of Platelets

SummaryEthanol, at physiologically tolerable concentrations, inhibits platelet responses to low concentrations of collagen or thrombin, but does not inhibit responses of washed rabbit platelets stimulated with high concentrations of ADP, collagen, or thrombin. However, when platelet responses to high concentrations of collagen or thrombin had been partially inhibited by prostacyclin (PGI2), ethanol had additional inhibitory effects on aggregation and secretion. These effects were also observed with aspirin- treated platelets stimulated with thrombin. Ethanol had no further inhibitory effect on aggregation of platelets stimulated with ADP, or the combination of ADP and epinephrine. Thus, the inhibitory effects of ethanol on platelet responses in the presence of PGI2 were very similar to its inhibitory effects in the absence of PGI2, when platelets were stimulated with lower concentrations of collagen or thrombin. Ethanol did not appear to exert its inhibitory effects by increasing cyclic AMP above basal levels and the additional inhibitory effects of ethanol in the presence of PGI2 did not appear to be brought about by further increases in platelet cyclic AMP levels.

Aggregation of Cat Platelets in Vitro

1970 ◽  
Vol 23 (03) ◽  
pp. 601-620 ◽  
Author(s):  
Th. B Tschopp
Keyword(s):  
Adenosine Monophosphate ◽  
Blood Collection ◽  
Base Line ◽  
Reversible Aggregation ◽  
Low Concentrations ◽  
Irreversible Aggregation ◽  
High Concentrations ◽  
Two Phases ◽  
Improved Technique

SummaryAggregation of cat platelets in the citrated plasma is examined by means of Born’s absorptiometer. A marked tendency of the platelets of this species to spontaneous aggregation necessitated first of all the development of an improved technique of blood collection.A hypothesis according to which 5-HT is released from the platelets, explains the absence of oscillations on the base line of the absorptiometer, the absence of platelet swelling, when ADP is added, and the effect of stirring on the aggregation curves in cat PRP. The average volume of cat platelets amounts to 10.46 μ3 when directly fixed in the blood, when fixed from PRP to 12.17 μ3, when fixed from stirred PRP to 13.51 μ3.In low concentrations (0.3-2 μM) ADP produce reversible aggregation; in narrowly restricted, individually dissimilar mean concentrations irreversible aggregation in two phases and in high concentrations, irreversible aggregation in one phase. Like ADP serotonin produces 2 phase irreversible aggregation in concentrations of 3-10 μM, but unlike ADP, the aggregation velocity decreases again with high 5-HT concentrations (>100 μM). Adrenaline does not produce aggregation and it is likely that adenosine and adenosine monophosphate inhibit the aggregation by serotonin but not by ADP. Species differences in the aggregation of human, rabbit and cat platelets are discussed.

The Action of an Aniline Derivative (AN 162) on Blood Coagulation and on Platelets

1971 ◽  
Vol 26 (01) ◽  
pp. 145-166
Author(s):  
E Deutsch ◽  
K Lechner ◽  
K Moser ◽  
L Stockinger
Keyword(s):  
Blood Coagulation ◽  
Citric Acid Cycle ◽  
Second Phase ◽  
Aniline Derivative ◽  
Acid Cycle ◽  
Enhancing Effect ◽  
Low Concentrations ◽  
Dual Action ◽  
High Concentrations ◽  
Induced Aggregation

Summary1. The aniline derivative AN 162, Donau Pharmazie, Linz, Austria, has a dual action on the blood coagulation: an anticoagulant and an coagulation enhancing effect.2. The anticoagulant action may only be demonstrated with high concentrations (over 1 X 10”3 M related to plasma) preferentially in PPP. It is partially caused by an inhibition of the endogenous way of generation of the prothrombin converting principle. In addition it is suggested that it interferes with the fibrinogen-fibrin reaction in a manner not yet understood.3. The coagulant action is caused by a greater availability of platelet constituents at low concentrations of AN 162 (over 1 × 10-4 M) and by the induction of a release reaction at higher concentrations. The platelet factors 3 and 4, serotonin, adenine, and acid phosphatase are released.4. AN 162 inhibits platelet aggregation. This inhibition can be demonstrated by the PAT of Breddin and in the stirred aggregation test of Born. It is more effective to inhibit the collagen-induced and the second phase of the adrenaline-induced aggregation than the ADP induced one. The platelet retention (test of Hellem) is also reduced.5. The action of AN 162 on the platelets is caused by a damage of the platelet membrane which becomes permeabel for both, soluble platelet constitutents and granula.6. AN 162 interferes with the energy metabolism of the platelets. It causes a loss of ATP, and inhibits the key-enzymes of glycolysis, citric acid cycle, fatty acid oxydation and glutathione reduction.7. AN 162 inhibits the growth of fibroblasts without influence on mitosis.

Functional Involvement of Thrombospondin in Platelet Aggregation Induced by Low Versus High Concentrations of Thrombin

1986 ◽  
Vol 55 (01) ◽  
pp. 136-142 ◽  
Author(s):  
K J Kao ◽  
David M Shaut ◽  
Paul A Klein
Keyword(s):  
Platelet Aggregation ◽  
Binding Sites ◽  
Inhibitory Effect ◽  
Activated Platelets ◽  
Low Concentrations ◽  
Platelet Binding ◽  
Functional Involvement ◽  
Thrombin Activation ◽  
Platelet Aggregates ◽  
High Concentrations

SummaryThrombospondin (TSP) is a major platelet secretory glycoprotein. Earlier studies of various investigators demonstrated that TSP is the endogenous platelet lectin and is responsible for the hemagglutinating activity expressed on formaldehyde-fixed thrombin-treated platelets. The direct effect of highly purified TSP on thrombin-induced platelet aggregation was studied. It was observed that aggregation of gel-filtered platelets induced by low concentrations of thrombin (≤0.05 U/ml) was progressively inhibited by increasing concentrations of exogenous TSP (≥60 μg/ml). However, inhibition of platelet aggregation by TSP was not observed when higher than 0.1 U/ml thrombin was used to activate platelets. To exclude the possibility that TSP inhibits platelet aggregation by affecting thrombin activation of platelets, three different approaches were utilized. First, by using a chromogenic substrate assay it was shown that TSP does not inhibit the proteolytic activity of thrombin. Second, thromboxane B2 synthesis by thrombin-stimulated platelets was not affected by exogenous TSP. Finally, electron microscopy of thrombin-induced platelet aggregates showed that platelets were activated by thrombin regardless of the presence or absence of exogenous TSP. The results indicate that high concentrations of exogenous TSP (≥60 μg/ml) directly interfere with interplatelet recognition among thrombin-activated platelets. This inhibitory effect of TSP can be neutralized by anti-TSP Fab. In addition, anti-TSP Fab directly inhibits platelet aggregation induced by a low (0.02 U/ml) but not by a high (0.1 U/ml) concentration of thrombin. In conclusion, our findings demonstrate that TSP is functionally important for platelet aggregation induced by low (≤0.05 U/ml) but not high (≥0.1 U/ml) concentrations of thrombin. High concentrations of exogenous TSP may univalently saturate all its platelet binding sites consequently interfering with TSP-crosslinking of thrombin-activated platelets.

The Utilization of Ftir (Fourier Transform Infra-Red) Method Combined with Chemometrics For Authentication of Indonesian Coffee Powder

2017 ◽  
Vol 9 (3) ◽  
Author(s):  
Firmansyah A. ◽  
Winingsih W. ◽  
Soebara Y S
Keyword(s):  
Fourier Transform ◽  
Natural Product ◽  
High Performance ◽  
Principal Component ◽  
Raw Material ◽  
Attenuated Total Reflectance ◽  
Coffee Bean ◽  
Product Analysis ◽  
Total Reflectance ◽  
And Cluster Analysis

Analysis of natural product remain challenging issues for analytical chemist, since natural products are complicated system of mixture. The most popular methods of choice used for quality control of raw material and finished product are high performance liquid chromatography (HPLC), gas chromatography (GC) and mass spectrometry (MS). The utilization of FTIR-ATR (Fourier Transform Infrared-Attenuated Total Reflectance) method in natural product analysis is still limited. This study attempts to expand the use of FTIR spectroscopy in authenticating Indonesian coffee powder.The coffee samples studied were taken from nine regions in Indonesia, namely Aceh Gayo, Flores, Kintamani, Mandheling, Papua, Sidikalang, Toraja, Kerinci and Lampung.The samples in the form of coffee bean from various regions were powdered . The next step conducted was to determine the spectrum using the FTIR-ATR (Attenuated Total Reflectance) using ZnSe crystal of 8000 resolution. Spectrum samples, then, were analyzed using chemometrics. The utilized chemometric model was the principal component analysis (PCA) and cluster analysis (CA). Based on the chemometric analysis, there are similarities between Aceh Gayo coffee with Toraja coffee, Mandailing coffee, Kintamani coffee and Flores coffee. Sidikalang coffee has a similarity to Flores coffee; Papua coffee has a similarity to Sidikalang coffee; Lampung coffee has a similarity to Sidikalang coffee, while Kerinci coffee has a similarity to Papua coffee.

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