scholarly journals Influence of spray mixture volume and flight height on herbicide deposition in aerial applications on pastures

2014 ◽  
Vol 32 (1) ◽  
pp. 227-232 ◽  
Author(s):  
M.A.P. Oliveira ◽  
U.R. Antuniassi ◽  
E.D. Velini ◽  
R.B. Oliveira ◽  
J.F. Salvador ◽  
...  

The objective of the present study was to analyze the influence of spray mixture volume and flight height on herbicide deposition in aerial applications on pastures. The experimental plots were arranged in a pasture area in the district of Porto Esperidião (Mato Grosso, Brazil). In all of the treatments, the applications contained the herbicides aminopyralid and fluroxypyr (Dominum) at the dose of 2.5 L c.p. ha-1, including the adjuvant mineral oil (Joint Oil) at the dose of 1.0 L and a tracer to determine the deposition by high-performance liquid chromatography (HPLC) (rhodamine at a concentration of 0.6%). The experiment consisted of nine treatments that comprised the combinations of three spray volumes (20, 30 and 50 L ha-1) and three flight heights (10, 30 and 40 m). The results showed that, on average, there was a tendency for larger deposits for the smallest flight heights, with a significant difference between the heights of 10 and 40 m. There was no significant difference among the deposits obtained with the different spray mixture volumes.

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Li-hua Chen ◽  
Yao Wu ◽  
Yong-mei Guan ◽  
Chen Jin ◽  
Wei-feng Zhu ◽  
...  

Fermented Cordyceps sinensis, the succedaneum of Cordyceps sinensis which is extracted and separated from Cordyceps sinensis by artificial fermentation, is commonly used in eastern Asia in clinical treatments due to its health benefit. In this paper, a new strategy for differentiating and comprehensively evaluating the quality of products of fermented Cordyceps sinensis has been established, based on high-performance liquid chromatography (HPLC) fingerprint analysis combined with similar analysis (SA), hierarchical cluster analysis (HCA), and the quantitative analysis of multicomponents by single marker (QAMS). Ten common peaks were collected and analysed using SA, HCA, and QAMS. These methods indicated that 30 fermented Cordyceps sinensis samples could be categorized into two groups by HCA. Five peaks were identified as uracil, uridine, adenine, guanosine, and adenosine, and according to the results from the diode array detector, which can be used to confirm peak purity, the purities of these compounds were greater than 990. Adenosine was chosen as the internal reference substance. The relative correction factors (RCF) between adenosine and the other four nucleosides were calculated and investigated using the QAMS method. Meanwhile, the accuracy of the QAMS method was confirmed by comparing the results of that method with those of an external standard method with cosines of the angles between the groups. No significant difference between the two methods was observed. In conclusion, the method established herein was efficient, successful in identifying the products of fermented Cordyceps sinensis, and scientifically valid to be applicable in the systematic quality control of fermented Cordyceps sinensis products.


2019 ◽  
Vol 60 (1) ◽  
pp. 19-25
Author(s):  
Kemalettin Acar ◽  
Ayse Kurtulus Dereli ◽  
Esin Avci ◽  
Volkan Zeybek ◽  
Erdi Kutlu ◽  
...  

This study aimed to determine haemoglobin A1c (HbA1c) levels in bloodstains shed on glass and fabric surfaces on specified test dates. Blood samples were taken from 26 patients (13 diabetic and 13 non-diabetic). Initial HbA1c levels were detected by using high-performance liquid chromatography (HPLC), and bloodstains were created on both cotton fabric and glass surfaces. Samples were processed at different ages (0, 7, 14, 28 and 56 days) by diluting distilled water and then measuring HbA1c levels by HPLC again. In all stains, HbA1c levels could be determined by using HPLC, but there was a moderate rise in accordance with the age of the stains. A statistically significant difference was found for bloodstains on clothes compared to those on glass surfaces. Receiver operating curve analysis found a sensitivity of 1.0 and specificity of 0.923 (cut-off 6.55) for glass surfaces on the seventh day; a sensitivity of 1.0, a specificity of 0.846 (cut-off 6.45) for clothes on the seventh day; a sensitivity of 1.0 and a specificity of 0.923 (cut-off 6.85) for clothes on the 56th day; and a sensitivity of 1.0 and a specificity of 0.846 (cut-off 7.55) for glass surfaces on the 56th day. In conclusion, this study found that HbA1c levels could be measured with high reliability from forensic bloodstains by using HPLC. Thus, in cases where DNA data banks cannot identify individuals, it would make sense to turn to those who have a medical history of diabetes among the suspects with the results of high HbA1c levels.


2016 ◽  
Vol 10 (01) ◽  
pp. 092-096 ◽  
Author(s):  
Huma Omurlu ◽  
Hacer Deniz Arisu ◽  
Evrim Eliguzeloglu Dalkilic ◽  
Ugur Tamer ◽  
Hilal Torul

ABSTRACT Objective: The purpose of the current study was to determine the amount of urethane dimethacrylate (UDMA), bisphenol A-glycidyl methacrylate (Bis-GMA), poly (ethylene glycol) dimethacrylate (PEGDMA), bisphenol A ethoxylated dimethacrylate (Bis-EMA), and 2-hydroxyethyl methacrylate (HEMA) eluted from resin-based root canal sealer, epiphany, using high-performance liquid chromatography (HPLC). Materials and Methods: Epiphany was placed into the plastic molds and light-cured with a light emitting diode. After the curing process, each specimen in the first group (n = 12) was immersed in Eppendorf tubes containing a phosphate-buffered saline solution (PBS) and incubated for 45 s. In the second group, each specimen (n = 12) was immersed in Eppendorf tubes containing PBS and incubated for 24 h. Of the specimen extracts, 100 μL were subjected to HPLC. Analysis of data was accomplished with one-way analysis of variance (P < 0.05). Results: All of the samples eluted HEMA, UDMA, Bis-GMA, PEGDMA, and Bis-EMA. A significant difference was determined between the time periods of HEMA, UDMA, PEGDMA, and Bis-EMA (P < 0.05). Conclusion: The results of the current study showed that Epiphany releases HEMA, UDMA, Bis-GMA, PEGDMA, and Bis-EMA in both time periods.


2018 ◽  
Vol 10 (1) ◽  
pp. 148
Author(s):  
Yahdiana Harahap ◽  
Lista Roro Marsudi ◽  
Sunarsih .

Objective: This study aimed to develop and validate an analytical method and to determine the effect of different anticoagulants for analyzingmetformin HCl level in human plasma.Methods: Analysis was performed with high-performance liquid chromatography method using a photodiode array detector set at 234 nm, a C18SunFire™ column (5 μm, 250 mm×4.6 mm), a temperature of 40°C, a mobile phase comprising 10 mM sodium dodecyl sulfate and 10 mM phosphatebuffer in water-acetonitrile (60:40 v/v) at pH 7.0, with a flow rate of 1.0 mL/min, and atorvastatin calcium as the internal standard. Plasmaextraction was performed through protein precipitation using human plasma (300 μL) and acetonitrile (600 μL; 1:2 v/v). The method was linear at aconcentration range of 20.0–5000.0 ng/mL, with r>0.9998.Results: The stability and recovery of metformin HCl in human plasma were not different between citrate with ethylenediaminetetraacetic acid(EDTA) and heparin with EDTA as anticoagulants. However, a significant difference in the peak area response ratio (p<0.05) was observed betweenthe three anticoagulants.Conclusion: The validation results for the three types of plasma anticoagulants met validation requirements based on the European MedicinesAgency bioanalytical guidelines of 2011 for accuracy and precision, selectivity, calibration curve linearity, dilution integrity, carry-over, and stability.


Author(s):  
Karolyne Gramlich De Melo ◽  
Siomara Regina Ferreira Jacobucci ◽  
Celia Regina Garlipp ◽  
Ângelo Zanaga Trape ◽  
Paulo César Pires Rosa

This study was conducted based on the evaluation of glyphosate levels present in rural workers in the region of Nova Mutum-MT. We analyzed 90 urine samples from farmers between 2017 and 2018. The samples were analyzed based on the development of the high-performance liquid chromatography (HPLC-FL) method. The results showed that 12% of the farmers presented glyphosate levels, but that the highest concentration determined by the method used was not above the limits allowed by Brazilian regulators. The HPLC-FL method proved to be practical and accurate for the determination of glyphosate in urine samples with limits of detection and quantification of 0.34 and 1.15ng/mL, respectively. These data show the importance of evaluating the occupational exposure of farmers to adopt strategies for the biomonitoring of this region, considering that casual exposures to pesticides can generate health risks, as well as cases of intoxication.


2019 ◽  
Vol 58 (4) ◽  
pp. 294-302
Author(s):  
Liangyuan Chen ◽  
Xiaomin Tang ◽  
Quan Yang ◽  
Xuanxuan Cheng

Abstract In this study, a valid and comprehensive evaluation method for assessing the quality of Desmodium styracifolium (Osb.) Merr has been established, based on analysis of high-performance liquid chromatography fingerprint combined with the similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA), discriminant analysis (DA) and the quantitative analysis multi-components by single marker (QAMS) method. Eleven peaks of the common model were obtained and analyzed using SA, HCA, PCA and DA analysis. These methods indicated a similar conclusion that 31 batches of D. styracifolium samples were categorized into two clusters basically coincident with their geographical regions of origin. Four peaks were identified as schaftoside, isoorientin, isoschaftoside and isovitexin. Schaftoside was selected as the internal standard, and the relative correction factors between schaftoside and the other three flavonoids were calculated using the QAMS method. The accuracy of the QAMS method was verified by comparing with the results calculated by the external standard method. No significant difference between the two methods was found. In conclusion, the established methods were scientifically applied in the quality evaluation of D. styracifolium.


2012 ◽  
Vol 32 (3) ◽  
pp. 568-572 ◽  
Author(s):  
José Masson ◽  
Maria das Graças Cardoso ◽  
Lidiany Mendonça Zacaroni ◽  
Jeancarlo Pereira dos Anjos ◽  
Adelir Aparecida Sackz ◽  
...  

Seventy-one samples of sugarcane spirits from small and average size stills produced in the northern and southern Minas Gerais (Brazil) were analyzed for acrolein using HPLC (High Performance Liquid Chromatography). Ethanol and copper concentrations and volatile acidity were also determined according to methods established by the Ministry of Agriculture, Livestock and Supply (MAPA). A total of 9.85% of the samples tested showed levels of acrolein above the legal limits, while the copper concentrations of 21.00% of the samples and the volatile acidity of 8.85% of the samples were higher than the limits established by the Brazilian legislation. The concentration of acrolein varied from 0 to 21.97 mg.100 mL-1 of ethanol. However, no significant difference at 5% of significance was observed between the samples produced in the northern and southern Minas Gerais. The method used for determination of acrolein in sugarcane spirits involved the formation of a derivative with 2,4-dinitrophenylhydrazine (2,4-DNPH) and subsequent analysis by HPLC.


Scientifica ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Vani Chandrashekar

Hb A1c measurement is subject to interference by hemoglobin traits and this is dependent on the method used for determination. In this paper we studied the difference between Hb A1c measured by HPLC in hemoglobin traits and normal chromatograms. We also studied the correlation of Hb A1c with age. Hemoglobin analysis was carried out by high performance liquid chromatography. Spearman’s rank correlation was used to study correlation between A1c levels and age. Mann-WhitneyUtest was used to study the difference in Hb A1c between patients with normal hemoglobin and hemoglobin traits. A total of 431 patients were studied. There was positive correlation with age in patients with normal chromatograms only. No correlation was seen in Hb E trait or beta thalassemia trait. No significant difference in Hb A1c of patients with normal chromatograms and patients with hemoglobin traits was seen. There is no interference by abnormal hemoglobin in the detection of A1c by high performance liquid chromatography. This method cannot be used for detection of A1c in compound heterozygous and homozygous disorders.


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