scholarly journals Statistically Coherent Calibration of X-Ray Fluorescence Spectrometry for Major Elements in Rocks and Minerals

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Surendra P. Verma ◽  
Sanjeet K. Verma ◽  
M. Abdelaly Rivera-Gómez ◽  
Darío Torres-Sánchez ◽  
Lorena Díaz-González ◽  
...  
Keyword(s):  
Linear Regression ◽  
Major Elements ◽  
Chemical Data ◽  
Confidence Limits ◽  
Total Uncertainty ◽  
X Ray ◽  
Analytical Instruments ◽  
Before And After ◽  
The Mean ◽  
Mean Concentration

We applied both the ordinary linear regression (OLR) and the new uncertainty weighted linear regression (UWLR) models for the calibration and comparison of a XRF machine through 59 geochemical reference materials (GRMs) and a procedure blank sample. The mean concentration and uncertainty data for the GRMs used for the calibrations (Supplementary Materials) (available here) filewere achieved from an up-to-date compilation of chemical data and their processing from well-known discordancy and significance tests. The drift-corrected XRF intensity and its uncertainty were determined from mostly duplicate pressed powder pellets. The comparison of the OLR (linear correlation coefficient r∼0.9523–0.9964 and 0.9771–0.9999, respectively, for before and after matrix correction) and UWLR models (r∼0.9772–0.9976 and 0.9970–0.9999, respectively) clearly showed that the latter with generally higher values of r is preferable for routine calibrations of analytical procedures. Both calibrations were successfully applied to rock matrices, and the results were generally consistent with those obtained in other laboratories although the UWLR model showed mostly narrower confidence limits of the mean (slope and intercept) or lower uncertainties than the OLR. Similar sensitivity (∼2.69–46.17 kc·s−1·%−1 for the OLR and ∼2.78–59.69 kc·s−1·%−1 for the UWLR) also indicated that the UWLR could advantageously replace the OLR model. Another novel aspect is that the total uncertainty can be reported for individual chemical data. If the analytical instruments were routinely calibrated from the UWLR model, this action would make the science of geochemistry more quantitative than at present.

Elements concentration analysis in groundwater from the North Serra Geral aquifer in Santa Helena-Brazil using SR-TXRF spectrometer

2012 ◽  
Vol 66 (5) ◽  
pp. 1029-1035 ◽  
Author(s):  
Gisele C. Justen ◽  
Fernando R. Espinoza-Quiñones ◽  
Aparecido Nivaldo Módenes ◽  
Rosangela Bergamasco
Keyword(s):  
Major Element ◽  
Monitoring Program ◽  
Major Elements ◽  
Regional Level ◽  
X Ray ◽  
The North ◽  
Tube Wells ◽  
The Mean ◽  
Mean Concentration ◽  
Groundwater Composition

In this work the analysis of elements concentration in groundwater was performed using the synchrotron radiation total-reflection X-ray fluorescence (SR-TXRF) technique. A set of nine tube-wells with serious risk of contamination was chosen to monitor the mean concentration of elements in groundwater from the North Serra Geral aquifer in Santa Helena, Brazil, during 1 year. Element concentrations were determined applying a SR-TXRF methodology. The accuracy of SR-TXRF technique was validated by analysis of a certified reference material. As the groundwater composition in the North Serra Geral aquifer showed heterogeneity in the spatial distribution of eight major elements, a hierarchical clustering to the data was performed. By a similarity in their compositions, two of the nine wells were grouped in a first cluster, while the other seven were grouped in a second cluster. Calcium was the major element in all wells, with higher Ca concentration in the second cluster than in the first cluster. However, concentrations of Ti, V, Cr in the first cluster are slightly higher than those in the second cluster. The findings of this study within a monitoring program of tube-wells could provide a useful assessment of controls over groundwater composition and support management at regional level.

scholarly journals The Relationship between Inflammation Markers (CRP, IL-6, sCD40L) and Colorectal Cancer Stage, Grade, Size and Location

Diagnostics ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1382
Author(s):  
Olga Martyna Koper-Lenkiewicz ◽  
Violetta Dymicka-Piekarska ◽  
Anna Justyna Milewska ◽  
Justyna Zińczuk ◽  
Joanna Kamińska
Keyword(s):  
Colorectal Cancer ◽  
Linear Regression ◽  
Tumor Size ◽  
Distal Colon ◽  
Proximal Colon ◽  
Model Parameters ◽  
Grade Group ◽  
Who Grade ◽  
The Mean ◽  
Mean Concentration

The aim of the study was the evaluation whether in primary colorectal cancer (CRC) patients (n = 55): age, sex, TNM classification results, WHO grade, tumor location (proximal colon, distal colon, rectum), tumor size, platelet count (PLT), mean platelet volume (MPV), mean platelet component (MCP), levels of carcinoembryonic antigen (CEA), cancer antigen (CA 19-9), as well as soluble lectin adhesion molecules (L-, E-, and P-selectins) may influence circulating inflammatory biomarkers: IL-6, CRP, and sCD40L. We found that CRP concentration evaluation in routine clinical practice may have an advantage as a prognostic biomarker in CRC patients, as this protein the most comprehensively reflects clinicopathological features of the tumor. Univariate linear regression analysis revealed that in CRC patients: (1) with an increase in PLT by 10 × 103/μL, the mean concentration of CRP increases by 3.4%; (2) with an increase in CA 19-9 of 1 U/mL, the mean concentration of CRP increases by 0.7%; (3) with the WHO 2 grade, the mean CRP concentration increases 3.631 times relative to the WHO 1 grade group; (4) with the WHO 3 grade, the mean CRP concentration increases by 4.916 times relative to the WHO 1 grade group; (5) with metastases (T1-4N+M+) the mean CRP concentration increases 4.183 times compared to non-metastatic patients (T1-4N0M0); (6) with a tumor located in the proximal colon, the mean concentration of CRP increases 2.175 times compared to a tumor located in the distal colon; (7) in patients with tumor size > 3 cm, the CRP concentration is about 2 times higher than in patients with tumor size ≤ 3 cm. In the multivariate linear regression model, the variables that influence the mean CRP value in CRC patients included: WHO grade and tumor localization. R2 for the created model equals 0.50, which indicates that this model explains 50% of the variance in the dependent variable. In CRC subjects: (1) with the WHO 2 grade, the mean CRP concentration rises 3.924 times relative to the WHO 1 grade; (2) with the WHO 3 grade, the mean CRP concentration increases 4.721 times in relation to the WHO 1 grade; (3) with a tumor located in the rectum, the mean CRP concentration rises 2.139 times compared to a tumor located in the distal colon; (4) with a tumor located in the proximal colon, the mean concentration of CRP increases 1.998 times compared to the tumor located in the distal colon; if other model parameters are fixed.

scholarly journals MWCNTs/ZnO Nanofibers Fabrication, Properties and Applications

2019 ◽  
Vol 16 (1) ◽  
pp. 196-211
Author(s):  
Magda Dawy Badry
Keyword(s):  
Food Packaging ◽  
Fiber Diameter ◽  
Aluminum Foil ◽  
Hexagonal Wurtzite Structure ◽  
Organic Precursor ◽  
X Ray ◽  
Before And After ◽  
Zno Nanofibers ◽  
The Mean ◽  
Xrd Patterns

Electrospun MWCNTs nanofibers (CNF1, CNF2 and CNF3) with different concentrations of MWCNTs (0.3, 1.5, 2 wt%), respectively, were deposited on Aluminum foil substrates.  Also,Zinc AcetatedihydrateZn(CH3COO)2.2H2O (ZNF) and MWCNTs/zinc acetate (CZNF)nanofiberswere deposited on Aluminum foil substratesand annealed in the presence of oxygen at 400 oC. The resultant fibers were characterized using X-ray differaction (XRD), scanning electron microscope with energy dispersive X-Ray spectrophotometry (SEM,EDX), Fourier transform infrared (FTIR). SEM,EDX and FTIR exhibited a total decomposition of the organic precursor after calcination and formation of zinc oxide (ZONF and CZONF). The mean fiber diameter was found to be increased with increasing MWCNTs concentration and ranged 490-767 nm. XRD patterns indicated that ZnO was corundum with the hexagonal wurtzite structure. The crystallite size of ZONF and CZONF were determined by shurrer equation to be26 and  29.7  nm, respectively. The optical analysis indicated that the percentage transmittance increased after calcination.The band gap for the electrospun fibers before and after calcination was calculated. CZONF nanofibers have elec­trical properties similar to those of semiconductors. The testedcompounds CNF2, CNF3, CZNF and CZONF exhibited different activities against the bacteriaand yeast pathogen Candidaalbicans. CZNF compound is the most active against the bacteria and yeast pathogen. So, these compounds can be used as food packaging.  

scholarly journals Imaging in the Evaluation of Endoscopic or Surgical Treatment for Achalasia

2016 ◽  
Vol 2016 ◽  
pp. 1-4
Author(s):  
Diego Palladino ◽  
Andrea Mardighian ◽  
Marilina D’Amora ◽  
Luca Roberto ◽  
Francesco Lassandro ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Digestive Tract ◽  
Endoscopic Treatment ◽  
Heller Myotomy ◽  
Esophageal Achalasia ◽  
Pneumatic Dilation ◽  
X Ray ◽  
Before And After ◽  
High Operative Risk ◽  
The Mean

Purpose.Aim of the study is to evaluate the efficacy of the endoscopic (pneumatic dilation) versus surgical (Heller myotomy) treatment in patients affected by esophageal achalasia using barium X-ray examination of the digestive tract performed before and after the treatment.Materials and Methods.19 patients (10 males and 9 females) were enrolled in this study; each patient underwent a barium X-ray examination to evaluate the esophageal diameter and the height of the barium column before and after endoscopic or surgical treatment.Results.The mean variation of oesophageal diameter before and after treatment is −2.1 mm for surgery and 1.74 mm for pneumatic dilation (OR 0.167, CI 95% 0.02–1.419, andP: 0.10). The variations of all variables, with the exception of the oesophageal diameter variation, are strongly related to the treatment performed.Conclusions.The barium X-ray study of the digestive tract, performed before and after different treatment approaches, demonstrates that the surgical treatment has to be considered as the treatment of choice of achalasia, reserving endoscopic treatment to patients with high operative risk and refusing surgery.

scholarly journals Foliar Micromorphology and Histochemical Localization of Specific Metabolites in the Leaves of Celosia argentea L.

2019 ◽  
Vol 47 (4) ◽  
pp. 1128-1135
Author(s):  
Oluwafunmilayo Dorcas ADEGBAJU ◽  
Gloria Aderonke OTUNOLA ◽  
Anthony Jide AFOLAYAN
Keyword(s):  
Glandular Trichomes ◽  
Major Elements ◽  
Digital Object Identifier ◽  
Abaxial Surface ◽  
X Ray ◽  
Sodium Calcium ◽  
Celosia Argentea ◽  
Histochemical Tests ◽  
The Mean ◽  
Information Database

Celosia argentea is an essential vegetable that is cultivated in the western part of Africa. This species has a growing reputation for its role in alleviating nutritional challenges and has found great application as herb of therapeutic importance in many regions of the world. This study investigated the foliar micromorphology and the histochemistry of Celosia argentea. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectrometry and staining agents were used to evaluate the micromorphology of the plant. The result revealed sunken amphistomatic stomata distribution on both surfaces of the leaf. Anomocytic and anisocytic stomata complexes were also observed on both epidermal surfaces. A definitive protuberance was observed on the polar end of the adaxial stomata. Stomata apparatus was ellipsoidal with a mean length of 19.60 ± 0.56 µm, while the mean stomata densities on the adaxial and abaxial surfaces were 83.5 ± 2.12 mm‑2 and 194.18 ± 3.70 mm‑2 respectively. Trichomes (with a length of 100.94 ± 9.44 µm) were sparsely distributed on both surfaces; glandular trichomes were observed only on the abaxial surface. The EDX spectrometry revealed the presence of iron, oxygen, sodium, calcium, potassium and sulphur as the major elements on the leaf, while histochemical tests revealed the presence of polyphenols, starch and lipids. Our results could be used to support and validate the information database on the anatomy of Celosia argentea.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Effect of iodide treatment on iodine concentration and volume of endemic non-toxic goitre in childhood

1985 ◽  
Vol 108 (1) ◽  
pp. 44-50 ◽  
Author(s):  
B. Leisner ◽  
B. Henrich ◽  
D. Knorr ◽  
R. Kantlehner
Keyword(s):  
Thyroid Volume ◽  
Iodine Concentration ◽  
Thyroxine Binding Globulin ◽  
X Ray ◽  
Thyroxine Therapy ◽  
Iodine Supplementation ◽  
Before And After ◽  
The Mean ◽  
Young Subjects ◽  
Normal Controls

Abstract. In a total of 195 children and adolescents of both sex (mean age 12.9, range 5–17 years) with endemic non-toxic goitre the thyroidal iodine concentration (IC) was determined using X-ray fluorescent scanning on admission and during iodine (100 μg daily) and l-thyroxine (3 μg/kg body weight daily) treatment respectively. Additionally the thyroid volume was measured sonographically in a longitudinal study including 46 patients before and after 4–8 months of iodine supplementation (100 μg daily). The IC was 305 ± 144 μg/g. It compared well with that of adult goitre patients (288 ± 109 μg/g) and was significantly inferior to the value of normal controls (389 ± 170 μg/g). Under l-thyroxine therapy the IC further decreased (243 ± 144 μg/g), whereas patients receiving iodide showed an increase of the IC (570 ± 197 μg/g). The mean TSH level fell from 2.3 ± 0.9 μU/ml to 1.4 ± 0.6 μU/ml. The average T4/TBG (thyroxine binding globulin) ratio showed a slight increase which, however, was not significant. The mean goitre volume decreased by 40%. It was evidenced that iodide is useful not only in the prophylaxis of non-toxic goitre but also as a more physiologic treatment than thyroid hormones, at least for young subjects with simple diffuse goitres.

Dry Effect of Cementitious Materials on Testing Results of X-Ray CT

2012 ◽  
Vol 450-451 ◽  
pp. 187-192 ◽  
Author(s):  
Jian De Han ◽  
Wei Sun ◽  
Gang Hua Pan
Keyword(s):  
Cement Paste ◽  
Three Dimensional ◽  
Cementitious Materials ◽  
Drying Process ◽  
X Ray ◽  
Before And After ◽  
X Ray Computed ◽  
The Mean ◽  
The Impact ◽  
Gray Values

In this study three-dimensional X-ray computed tomography (X-ray CT) is used to investigate the testing results differences of cement paste and mortar before and after drying. It can be found that the mean gray values of paste and mortar before drying are bigger than after drying, and the impact of drying on cement paste is more serious than mortar. In addition, the porosity of non-drying cement paste and mortar is 1.10% and 0.43%, while that of drying cement paste and mortar is 1.55% and 0.70%, respectively. So, the porosity of paste and mortar markedly increases after drying process. The numbers of pores of paste and mortar sharply increase after drying process in particular between 0.01mm3 and 0.1mm3. The impact of drying on smaller pores is more serious than bigger pores.

scholarly journals Plasma and ovarian oestradiol and the variability in the LH surge induced in ewes by the ram effect

Reproduction ◽  
2015 ◽  
Vol 149 (5) ◽  
pp. 511-521 ◽  
Author(s):  
Claude Fabre-Nys ◽  
Audrey Chanvallon ◽  
Nathalie Debus ◽  
Dominique François ◽  
Frédéric Bouvier ◽  
...  
Keyword(s):  
Granulosa Cells ◽  
Plasma Concentrations ◽  
Feedback Signal ◽  
Sexually Active ◽  
Lh Surge ◽  
Before And After ◽  
Ram Effect ◽  
The Mean ◽  
Mean Concentration

The proportion of anoestrous ewes ovulating after exposure to a sexually active ram is variable mainly due to whether an LH surge is induced. The aim of this study was to determine the role of oestradiol (E2) in the ram-induced LH surge. In one study, we measured the plasma concentrations of E2 in ewes of different breeds before and after the ‘ram effect’ and related these patterns to the presence and latency of the LH surge, while another compared ovarian responses with the ‘ram effect’ following exposure to rams for 2 or 12 h. In all ewes, the concentration of E2 increased 2–4 h after rams were introduced and remained elevated for 14.5±0.86 h. The quantity of E2 secreted before the LH surge varied among breeds as did the mean concentration of E2. The granulosa cells of IF ewes collected after 12 h exposure to rams secreted more E2 and progesterone and had higher levels of StAR than the 2 h group but in MV ewes there was no differences between these groups for any of these parameters. These results demonstrate that the LH surge induced by the rams is a result of increased E2 secretion associated with increased levels of STAR in granulosa cells and that these responses varied among breeds. The results suggest that the variable occurrence of a LH surge and ovulation may be the result of variable ovarian responses to the ‘ram effect’ and insensitivity of the hypothalamus to the E2-positive feedback signal.Free French abstract: A French translation of this abstract is freely available at http://www.reproduction-online.org/content/149/5/511/suppl/DC1.

scholarly journals HUBUNGAN RENANG DENGAN KONSENTRASI PADA ANAK

2017 ◽  
Vol 8 (1) ◽  
pp. 602
Author(s):  
Ainul Mardliyah ◽  
Susiana Candrawati ◽  
Dewi Nilamsari
Keyword(s):  
Experimental Study ◽  
Sampling Method ◽  
Wilcoxon Test ◽  
Control Group ◽  
Significant Relation ◽  
Control Group Design ◽  
Group Design ◽  
Before And After ◽  
The Mean ◽  
Mean Concentration

Background. The ability to sustain attention over period of time is called concentration. Concentration is one of the important factor for studying, especially for school children. Swimming as an exercise expected to be improving concentration.Objective. The aim of this study was to know the relation between swimming and concentration in childrens.Method. This study was experimental study with pre-posttest without control group design. Subjects were 8 children within 6-12 years old (age 8,50 + 1,41) by total sampling method. Swimming had been done 2 times a week in mild intensity with 60 minutes duration for 8 weeks at Bina Taruna swimming club, Purwokerto. Concentration score before and after the intervention was measured with army-alpha test by pshycologist. Wilcoxon test was performed to determine the relation between swimming and concentration.Results. There was significant relation between swimming and concentration (p= 0,042). The mean concentration score had increased after the 8-weeks swimming intervention (76,25+ 13,30 to 83,13 + 9,98.)Conclusion. There was relation between swimming and concentration in children

scholarly journals Plasma PGFM and progesterone concentrations, luteolysis moment and estrous cycle length in Nelore cows submitted to uterine biopsies

2015 ◽  
Vol 67 (5) ◽  
pp. 1210-1216
Author(s):  
I. Martin ◽  
C. M. B. Membrive ◽  
L. F. Vettorato ◽  
M. Binelli ◽  
E. Oba ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Estrous Cycle ◽  
Mean Value ◽  
Endometrial Biopsy ◽  
Control Group ◽  
Minimum Concentration ◽  
Before And After ◽  
The Mean ◽  
And Control ◽  
Mean Concentration

ABSTRACTIn this study, endometrial samples were collected in 14 Nelore cows on days zero (ovulation), five, nine, thirteen and nineteen of the estrous cycle (biopsy group), and in 15 females these collections weren't performed (control group). Biopsies were done on the uterine horn endometrium contralateral to the ovary with corpus luteum. Blood samples were taken at -24, -16, -8, 0 +8, +16 and +24 hours in relation to progesterone drop (<1ng/mL, zero moment) and evaluated for 13, 14-dihydro-15-keto prostaglandin F2-alpha (PGFM) by radioimmunoassay (RIA). Plasma progesterone concentration was determined by RIA every 24 hours. Data were analyzed by ANOVA using the PROC GLM and MIXED of the SAS. The mean value for PGFM during the entire period evaluated was greater in the biopsy group. The mean concentration of PGFM at moment zero was not different between the groups; the mean concentration of PGFM was higher in the biopsy group before and after the drop in progesterone level. The maximum mean concentration observed was not different between the groups; however, the mean minimum concentration was different with high values in the biopsy group. Although the PGFM concentrations were higher in the biopsy group, the biopsy and control groups had similar length of estrous cycle showing that repeated endometrial biopsy on the side contralateral to the ovary with corpus luteum does not affect luteolysis and the length of the estrous cycle.

Sign in / Sign up

Export Citation Format

Share Document