scholarly journals Development of Candidate Reference Materials of Endosulfan Sulfate and Bifenthrin in Black Tea

2018 ◽  
Vol 16 (1) ◽  
pp. 72 ◽  
Author(s):  
Nurhani Aryana ◽  
Yosi Aristiawan ◽  
Dillani Putri ◽  
Dyah Styarini
Keyword(s):  
Reference Materials ◽  
Collaborative Study ◽  
Black Tea ◽  
Uncertainty Budget ◽  
Dry Mass ◽  
Endosulfan Sulfate ◽  
Expanded Uncertainty ◽  
Short Term ◽  
Relative Expanded Uncertainty ◽  
Characterization Procedure

The candidate reference materials of endosulfan sulfate and bifenthrin in black tea have been developed according to the requirements of ISO Guide 34 and 35. Preparation of candidate material includes grinding and sieving of the black tea leaves, spiking the black tea powder by both analytes, homogenization, and bottling. Homogeneity and short-term stability test were performed using a GC-µECD instrument. Meanwhile, the characterization was carried out by a collaborative study using both of GC-µECD and GC-MS instruments. The uncertainty budget was evaluated from sample inhomogeneity, short-term instability and variability in the characterization procedure. In a dry mass fraction, endosulfan sulfate was assigned to be 491 µg kg-1 with a relative expanded uncertainty of ± 33.2%, and bifenthrin was assigned to be 937 µg kg-1 with a relative expanded uncertainty of ± 18.5%. The candidate reference materials are aimed to support the need of matrix CRM especially for the measurement of pesticide residue for quality assurance work done by laboratories in Indonesia.

Estimation of uncertainty in olfactometry

2009 ◽  
Vol 59 (7) ◽  
pp. 1409-1413 ◽  
Author(s):  
T. Higuchi
Keyword(s):  
Measurement Uncertainty ◽  
Interlaboratory Comparison ◽  
Collaborative Study ◽  
Estimation Procedure ◽  
Measurement Model ◽  
Standard Uncertainty ◽  
Expanded Uncertainty ◽  
Collaborative Test ◽  
Measurement Results ◽  
Estimation Of Uncertainty

Estimation of uncertainty in odour measurement is essential to the interpretation of the measurement results. The fundamental procedure for the estimation of measurement uncertainty comprises the specification of the measurement process, expression of the measurement model and all influences, evaluation of the standard uncertainty of each component, calculation of the combined standard uncertainty, determination of a coverage factor, calculation of the expanded uncertainty and reporting. Collaborative study such as interlaboratory comparison of olfactometry yields performance indicators of the measurement method including repeatability and reproducibility. Therefore, the use of collaborative test results for measurement uncertainty estimation according to ISO/TS 21748 and ISO 20988 is effective and reasonable. Measurement uncertainty of the triangular odour bag method was estimated using interlaboratory comparison data from 2003 to 2007 on the basis of the simplest model of statistical analysis, and the expanded uncertainty of odour index ranged between 3.1 and 6.7. On the basis of the establishment of the estimation procedure for uncertainty, a coherent interpretation method for the measurement results will be proposed and more effective and practical quality control of olfactometry will be available.

scholarly journals Crop residues on short-term CO2 emissions in sugarcane production areas

2013 ◽  
Vol 33 (4) ◽  
pp. 699-708 ◽  
Author(s):  
Mariana M. Corradi ◽  
Alan R. Panosso ◽  
Marcílio V. Martins Filho ◽  
Newton La Scala Junior
Keyword(s):  
Co2 Emissions ◽  
Field Experiments ◽  
Crop Residues ◽  
Soil Surface ◽  
Dry Mass ◽  
Agricultural Crop ◽  
Short Term ◽  
Sugarcane Production ◽  
Soil Temperatures ◽  
Production Areas

The proper management of agricultural crop residues could produce benefits in a warmer, more drought-prone world. Field experiments were conducted in sugarcane production areas in the Southern Brazil to assess the influence of crop residues on the soil surface in short-term CO2 emissions. The study was carried out over a period of 50 days after establishing 6 plots with and without crop residues applied to the soil surface. The effects of sugarcane residues on CO2 emissions were immediate; the emissions from residue-covered plots with equivalent densities of 3 (D50) and 6 (D100) t ha-1 (dry mass) were less than those from non-covered plots (D0). Additionally, the covered fields had lower soil temperatures and higher soil moisture for most of the studied days, especially during the periods of drought. Total emissions were as high as 553.62 ± 47.20 g CO2 m-2, and as low as 384.69 ± 31.69 g CO2 m-2 in non-covered (D0) and covered plot with an equivalent density of 3 t ha-1 (D50), respectively. Our results indicate a significant reduction in CO2 emissions, indicating conservation of soil carbon over the short-term period following the application of sugarcane residues to the soil surface.

scholarly journals The problem of improving the quality of seriously issued certified reference materials of the composition of gas mixtures

2019 ◽  
Vol 15 (3) ◽  
pp. 5-13
Author(s):  
L. A. Konopelko ◽  
A. V. Kolobova ◽  
O. V. Fatina
Keyword(s):  
Reference Material ◽  
Reference Materials ◽  
Certified Reference Materials ◽  
Metrological Traceability ◽  
Gas Mixtures ◽  
Measuring Instruments ◽  
Expanded Uncertainty ◽  
Iso Guide 35 ◽  
The Russian Federation

Currently, in the Russian Federation, the metrological traceability of certified reference materials of the composition of gas mixtures in cylinders under pressure produced by manufacturers of certified reference materials is carried out in accordance with GOST 8.578-2014. Considering that certified reference materials of the composition of gas mixtures in cylinders under pressure are used for testing to approye the type of measuring instruments, verification, calibration, and graduation of gas-analytical measuring instruments used to control explosive gases and vapors, harmful components in the atmospheric air and the air of the working area, emissions from vehicles and enterprises, to control technological processes, the quality of hydrocarbon products, etc., the issue of ensuring the quality of seriously produced certified reference materials (about 100.000 cylinders with gas mixtures per year) is important. To ensure the quality of certified reference materials of gas mixtures in cylinders under pressure, mass-produced by manufacturers of certified reference materials, we offer the following actions:– manufacturers of certified reference materials’ passing of mandatory accreditation for compliance with the requirements of GOST ISO Guide 34–2014 and GOST ISO Guide 35–2015;– manufacturers of certified reference materials’ constant participation in the proficiency testing programs through interlaboratory tests;– actualizing and refining the existing set of standards defining the requirements for the entire life cycle of a certified reference material of a gas mixture in a cylinder under pressure;– improving the method of certification of a reference material by calculating the value of the expanded uncertainty of the reference material and the introducting a new coefficient «technological reserve».

scholarly journals Prospective Zinc Solubilising Bacteria for Enhanced Nutrient Uptake and Growth Promotion in Maize (Zea maysL.)

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Praveen Kumar Goteti ◽  
Leo Daniel Amalraj Emmanuel ◽  
Suseelendra Desai ◽  
Mir Hassan Ahmed Shaik
Keyword(s):  
Plant Growth ◽  
Solid Medium ◽  
Growth Promotion ◽  
Dry Mass ◽  
Short Term ◽  
Culture Experiment ◽  
Zinc Supplement ◽  
Seed Bacterization ◽  
Significant Release ◽  
Pot Culture

Zinc (Zn) is one of the essential micronutrients required for optimum plant growth. Substantial quantity of applied inorganic zinc in soil is converted into unavailable form. Zinc solubilising bacteria are potential alternates for zinc supplement. Among 10 strains screened for Zn solubilisation, P29, P33, and B40 produced 22.0 mm clear haloes on solid medium amended with ZnCO3. Similarly, P17 and B40 showed 31.0 mm zone in ZnO incorporated medium. P29 and B40 showed significant release of Zn in broth amended with ZnCO3(17 and 16.8 ppm) and ZnO (18 and 17 ppm), respectively. The pH of the broth was almost acidic in all the cases ranging from 3.9 to 6.1 in ZnCO3and from 4.1 to 6.4 in ZnO added medium. Short term pot culture experiment with maize revealed that seed bacterization with P29 @ 10 g·kg−1significantly enhanced total dry mass (12.96 g) and uptake of N (2.268%), K (2.0%), Mn (60 ppm), and Zn (278.8 ppm).

Development, validation, and certification by isotope dilution gas chromatography-mass spectrometry of lyophilized human serum reference materials for cortisol (CRM 192 and 193) and progesterone (CRM 347 and 348)

1991 ◽  
Vol 37 (4) ◽  
pp. 540-546 ◽  
Author(s):  
Linda Thienpont ◽  
Lothar Siekmann ◽  
Alexander Lawson ◽  
Elisabeth Colinet ◽  
Andrȳ De Leenheer
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Reference Materials ◽  
Isotope Dilution ◽  
Certified Reference Materials ◽  
Collaborative Study ◽  
Gas Chromatography Mass Spectrometry ◽  
Chromatography Mass Spectrometry ◽  
Coefficients Of Variation

Abstract The Community Bureau of Reference of the European Communities has produced four batches of lyophilized serum Certified Reference Materials, two for cortisol (CRM 192 and 193) and two for progesterone (CRM 347 and 348). For cortisol, one of the pools consisted of serum from healthy blood donors, whereas the second batch was supplemented with pure cortisol. The progesterone Reference Materials contained only endogenous hormone concentrations. Assessment of vial-to-vial variability in the cortisol and progesterone concentrations showed no between-sample inhomogeneity, and the materials were stable. The quality of the materials was therefore considered sufficient for certification of the values for the cortisol and progesterone concentrations by a collaborative study involving several laboratories from the European Communities, using isotope dilution gas chromatography-mass spectrometry. Inaccuracy in reconstitution of the lyophilized materials was less than 0.3%; imprecision of sampling was less than 0.2%. For determinations of cortisol and progesterone concentrations, the mean within-laboratory coefficients of variation (CVs) were 1.76% (CRM 192), 1.19% (CRM 193), 1.64% (CRM 347), and 1.75% (CRM 348). The between-laboratory CVs were greater: CRM 192, 1.79%; CRM 193, 1.48%; CRM 347, 2.08%; and CRM 348, 2.16%. The concentrations in the reconstituted Reference Materials were certified to be 273 nmol/L in CRM 192 and 763 nmol/L in CRM 193 for cortisol and 10.13 nmol/L in CRM 347 and 40.3 nmol/L in CRM 348 for progesterone. Uncertainties at the 0.95 confidence level--6 (CRM 192), 14 (CRM 193), 0.21 (CRM 347), and 1.0 nmol/L (CRM 348)--were considered compatible with the intended use of the materials.

Effect of adding milk to black tea on vascular function in healthy men and women: a randomised controlled crossover trial

2018 ◽  
Vol 9 (12) ◽  
pp. 6307-6314 ◽  
Author(s):  
Adilah F. Ahmad ◽  
Lisa Rich ◽  
Henrietta Koch ◽  
Kevin D. Croft ◽  
Mario G. Ferruzzi ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Vascular Function ◽  
Crossover Trial ◽  
Black Tea ◽  
Tea Consumption ◽  
Short Term ◽  
Men And Women ◽  
Healthy Men ◽  
Randomised Controlled ◽  
P Addition

Addition of milk to black tea alters the acute/short-term benefical effect of regular black tea consumption on vascular function and blood pressure.

Characterization of SiGe Films for Use as a National Institute of Standards and Technology Microanalysis Reference Material (RM 8905)

2009 ◽  
Vol 16 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Ryna B. Marinenko ◽  
Shirley Turner ◽  
David S. Simons ◽  
Savelas A. Rabb ◽  
Rolf L. Zeisler ◽  
...  
Keyword(s):  
Reference Materials ◽  
Silicon Germanium ◽  
Mass Fraction ◽  
Thick Films ◽  
Nominal Composition ◽  
Expanded Uncertainty ◽  
Electron Probe Microanalyzer ◽  
Microelectronics Industry ◽  
The Mean

AbstractBulk silicon-germanium (SiGe) alloys and two SiGe thick films (4 and 5 μm) on Si wafers were tested with the electron probe microanalyzer (EPMA) using wavelength dispersive spectrometers (WDS) for heterogeneity and composition for use as reference materials needed by the microelectronics industry. One alloy with a nominal composition of Si0.86Ge0.14 and the two thick films with nominal compositions of Si0.90Ge0.10 and Si0.75Ge0.25 on Si, evaluated for micro- and macroheterogeneity, will make good microanalysis reference materials with an overall expanded heterogeneity uncertainty of 1.1% relative or less for Ge. The bulk Ge composition in the Si0.86Ge0.14 alloy was determined to be 30.228% mass fraction Ge with an expanded uncertainty of the mean of 0.195% mass fraction. The thick films were quantified with WDS-EPMA using both the Si0.86Ge0.14 alloy and element wafers as reference materials. The Ge concentration was determined to be 22.80% mass fraction with an expanded uncertainty of the mean of 0.12% mass fraction for the Si0.90Ge0.10 wafer and 43.66% mass fraction for the Si0.75Ge0.25 wafer with an expanded uncertainty of the mean of 0.25% mass fraction. The two thick SiGe films will be issued as National Institute of Standards and Technology Reference Materials (RM 8905).

scholarly journals Development of certified reference materials for physicochemical analysis. Certified reference solutions for the composition of aqueous aluminum, indium, magnesium, nickel and titanium

2019 ◽  
Vol 15 (3) ◽  
pp. 23-32
Author(s):  
I. I. Ermakova ◽  
A. V. Ivanov ◽  
I. N. Zyablikova ◽  
A. N. Shobina
Keyword(s):  
Reference Materials ◽  
Mass Concentration ◽  
Certified Reference Materials ◽  
Storage Conditions ◽  
Physicochemical Analysis ◽  
Standard Uncertainty ◽  
Expanded Uncertainty ◽  
State Register ◽  
Physical Measurements ◽  
Relative Standard

This paper presents information on the development and certification of reference materials (CRM) for the composition of aqueous aluminium, indium, magnesium, nickel, and titanium solutions.CRMs are represented by aqueous solutions containing aluminium, indium, magnesium, nickel, and titanium ions. CRMs have been packed into 5, 10 and 25 cm3 glass ampoules, as well as into 50 and 250 cm3 polypropylene vessels. The certified values of metal mass concentrations were established according to the preparation method.The certified value of the mass concentration of metal ions in the CRMs under study is found to vary within the range of 0.95–1.06 g/dm3. Both the relative expanded uncertainty (under k= 2) of the certified mass concentration and the relative standard uncertainty due to instability do not exceed the values of 0.8 % and 0.069 %, respectively. The developed CRMs are shown to have the shelf life of 3 years provided that standard storage conditions are ensured. The developed CRMs are included into the RF State Register of Certified Reference Materials under the following numbers: CRM 11122–2018, CRM 11123–2018, CRM 11124–2018, CRM 11125–2018, and CRM 11126–2018. The CRMs produced by the All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI) are characterized by the values of expanded uncertainty comparable to those of world leaders in the production of similar materials.

scholarly journals Short-Term Tea Consumption Is Not Associated with a Reduction in Blood Lipids or Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

2020 ◽  
Vol 150 (12) ◽  
pp. 3269-3279
Author(s):  
Ebuwa Igho-Osagie ◽  
Kelly Cara ◽  
Deena Wang ◽  
Qisi Yao ◽  
Laura P Penkert ◽  
...  
Keyword(s):  
Systematic Review ◽  
Blood Pressure ◽  
At Risk ◽  
Ldl Cholesterol ◽  
Meta Analysis ◽  
Hdl Cholesterol ◽  
Black Tea ◽  
Tea Consumption ◽  
Short Term ◽  
High Quality

ABSTRACT Background A recent systematic review of epidemiological evidence suggests that higher amounts of tea intake are associated with lower risks of cardiovascular disease (CVD) incidence and mortality. Objectives Our study objective was to assess mechanisms by which tea consumption may influence CVD risks. Methods A systematic review and meta-analysis was conducted to investigate the effects of green and/or black tea consumption (≥4 wk) on systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride (TG) in healthy populations and among at-risk adults (analyzed separately) with metabolic syndrome, prediabetes, and hypercholesterolemia. The Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the strength of evidence (SoE). Results A total of 14 unique RCTs which randomly assigned 798 participants to either green tea, black tea, or placebo controls were included in our analyses. Intervention durations ranged from 4 to 24 wk (mean: 7.4 wk). Individual studies were judged as moderate to high quality based on risk of bias assessments. SoE was low to moderate owing to low sample sizes and insufficient power for most included studies to observe changes in the measured CVD biomarkers. Meta-analyses showed no significant effects of tea consumption on SBP, DBP, total cholesterol, LDL cholesterol, HDL cholesterol, and TG in healthy and at-risk adults (i.e., adults with obesity, prediabetes, borderline hypercholesterolemia, and metabolic syndrome). Conclusions Short-term (4–24 wk) tea consumption does not appear to significantly affect blood pressure or lipids in healthy or at-risk adults, although the evidence is limited by insufficient power to detect changes in these CVD biomarkers. High-quality RCTs with longer durations and sufficient sample sizes are needed to fully elucidate the effects of tea. This systematic review was registered at www.crd.york.ac.uk/prospero/ as CRD42020134513.

scholarly journals Global Citizenship through Global Health

2019 ◽  
Vol 31 (1) ◽  
pp. 131-147
Author(s):  
Lee Stoner ◽  
Michael A. Tarrant ◽  
Lane Perry ◽  
Mikell Gleason ◽  
Daniel Wadsworth ◽  
...  
Keyword(s):  
Global Health ◽  
Study Abroad ◽  
Global Citizenship ◽  
Collaborative Study ◽  
Health Study ◽  
Lifestyle Behaviors ◽  
Short Term ◽  
Socially Responsible ◽  
Global Issues ◽  
Study Abroad Program

A collaborative study abroad program (between one New Zealand and one U.S. university) on the theme of global health has been offered three times in Australia with 59 students registered to date. The course was developed because it is believed that higher education can play a role in improving global health through the fostering of global citizenship A global citizen is one who is aware of global issues, socially responsible, and civica lly engaged. From this perspective, personal health is not solely an individual , self serving act; rather, the consequences of an individual’s lifestyle behaviors have deep and wide consequences extending to the community, national, and global contexts. Our paper provides a narrative on the framework used to develop the aforementioned global health study abroad course, including 1 ) an initial discussion on the intricate relationship between global citizenship and global health; 2 ) previous evidence demonstrating that short term study abroad has the potential to foster global citizenship; and 3 ) the specific process used to develop the current short term, faculty led, interdisciplinary, experiential study abroad course.

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