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2022 ◽  
Vol 2149 (1) ◽  
pp. 012006
Author(s):  
Kinza Maham ◽  
Petri Kärhä ◽  
Farshid Manoocheri ◽  
Erkki Ikonen

Abstract We report realization of scales for optical power of lasers and spectral responsivity of laser power detectors based on a predictable quantum efficient detector (PQED) over the spectral range of 400 nm–800 nm. The PQED is characterized and used to measure optical power of a laser that is further used in calibration of the responsivities of a working standard trap detector at four distinct laser lines, with an expanded uncertainty of about 0.05%. We present a comparison of responsivities calibrated against the PQED at Aalto and the cryogenic radiometer at RISE, Sweden. The measurement results support the concept that the PQED can be used as a primary standard of optical power.



2021 ◽  
Author(s):  
Nico Lelie ◽  
Marco Koppelman ◽  
Harry Van Drimmelen ◽  
Sylvia Bruisten

We prepared severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) working standards and reference panels from a pool of swab fluid samples before and after inactivation by beta-propiolactone and quantified viral load in nucleic acid amplification technology (NAT) detectable RNA copies/mL using limiting dilution analysis. The following 50% lower limits of detection (LOD) were estimated by probit analysis as compared to detection limits of rapid antigen tests on 1.5 fold dilutions of the native material: Roche cobas PCR 1.8 (1.0-3.3), Hologic Aptima TMA 6.6 (4.4-9.9), DRW SAMBA 15 (7-30), Molgen LAMP 23 (13-42), Fluorecare antigen 50,000, Abbott Panbio antigen 75,000 and Roche antigen 100,000 copies/mL. One 50% Tissue Culture Infectious Dose (TCID50)/mL of culture fluid was estimated to be equivalent to approximately 1000 RNA copies/mL (2700- 4300 International Units) in our working standard. When assuming this level as start of contagiousness in a log-linear ramp up viremia model with 10-fold rise of viral load per day for the B.1 (Wuhan) type we estimated relative time points of first detectability of early infection by the different SARS-CoV-2 assays from the LODs mentioned above. The four NAT assays would be able to detect early viremia 40-66 hours earlier than the 1000 copies/mL infectivity threshold, whereas the three antigen tests would become positive 41-48 hours later. Our modeling of analytical sensitivity data was found to be compatible with clinical sensitivity data of rapid antigen tests and confirms that NAT assays are more reliable than antigen assays for identifying early infected asymptomatic individuals who are potentially infectious.



Helminthiasis has been a major public health problem in Southeast Asia, especially in rural areas significant along the Thai national borderline. This research within provincial public health working standard aimed to identify the situation and influent factors along 3 sequential purposes within 3 steps as 1)To explore 5 years situation to get the specific study area, 2)To find out the prevalence of the area, and 3)To excrete the influent factors. The target area of the first step comprised 2 subdistricts, Donrak and Phrai Phattana within 9873 parents who participated in the stool examination program in 2015-2019 under the provincial Public Health Office, of primary school pupils. In the second step specific area were selected via the criteria of 30 percentile of the high border length line which were 2 subdistricts. 469 parents in those did re-examine their stool in the last 3 months in 2019 to compare the 2 sets of the prevalence. In both steps of the analysis, basic data were gender and 6 age ranges (Min = 20 years old, Max > 60 years old).In the final step, influent factors based on the documents and congruence among 6 responsible staffs with an equal number in each, The stool examination was FECT and helminthiasis simple smear in the first 2 steps was in the same standard. In the third one, the excreted factors were supported by theories and 100 percent of the congruence. The results were as 1)In the first step, 15.96% among 9873 subjects were infected. Male (n=893)was statistically significant higher (P<=.05) than female(n=682).The age range mode was 41-50 years old. 2)In the second step, 21 % among 496 subjects were infected. Male(n=37)was statistically significant higher than female(n=13) at .05 level. Age range mode was in 40-50 years old in both subdistricts. 3)In the final step, 3 influent factors were delivered out as the number of water resources and geographical patient location, and fish consuming behavior. The beyond results besides the purposes revealed prevalence of helminthiasis comprised; Opisthorchis viverrini (47.08%), hookworm (28.17%), and Taenia spp (6.91%). This was crucial for further investigation in each type to be able to link into both the public health and helminth professional area.



2021 ◽  
Author(s):  
Andrew C.H. Au ◽  
◽  
Brenda H.S. Lam ◽  
Y.C. Kwan ◽  
Angus K.K. Tung

The Standards and Calibration Laboratory (SCL) in Hong Kong has developed a system for calibration of quarter-inch working standard (WS3) microphones which automates the measurement process and generates digital calibration certificates (DCC) to meet the growing demand for microphone calibration services in Hong Kong. This paper describes (i) the method of determining the pressure sensitivity of a microphone combination unit from 20 Hz to 20 kHz by the comparison technique in accordance with the International Standard IEC 61094-5, (ii) the measurement model and uncertainty evaluation, and (iii) the automatic system which facilitates the calibration process and generation of a digital calibration certificate.



2021 ◽  
Vol 14 (9) ◽  
pp. 69
Author(s):  
Songsak Phusee-orn

The purposes of this research are to compare the practice between working standard and personal working standard of teachers who are certified by attending professional teacher knowledge standard workshop held by the teachers&rsquo; council who are different in gender, age, ways of knowledge certified and teaching according to/not according to educational certificate background. The samples are 246 research participants certified by attending professional teacher knowledge standard workshop of the teacher&rsquo;s council: Developmental division of the Faculty of Education, Mahasarakham University. Sampling operated by using Multi-Stage Random Sampling. Teachers&rsquo; data collection are self-evaluation and with school directors also as informers. Research instrument are piloted quality inspected questionnaire indicated by Item Total Correlation and Reliability of Cronbach. Data are analyzed by using X, s.d., t-test: independent samples, One way ANOVA, and multiple comparison of Scheffe. The research found that: 1) Overall, the female teachers who have been certified by attending professional teacher knowledge standard workshop of the teacher&rsquo;s council follow teaching standard in the academic activities facets on professional teacher&rsquo;s development and self-practice standard and ethic is higher than male teachers with statistically significant at the .05 level. 2) Teachers who with age differences follow the standard of being a good role model for the students. They work cooperatively with others in the community creatively. Personal practice standard about ethic to society is different with statistically significant at the .05 level. 3) Teachers who have been certified by attending professional teacher knowledge standard workshop of the teacher&rsquo;s council foster on teacher professional development and immensely develop the students to their full potential more than transferring method with statistically significant at the .05 level. 4) Teachers who teach according to educational certificate background practice according to the standard professional teacher on designing learning activities with the students in mind. They thrive so as to make every opportunity to be for learning. They also have higher ethic than teachers who are not teaching according to their educational certificate background with statistically significant at the .05 level.



2021 ◽  
Vol 2 ◽  
Author(s):  
Mykhailo Rozhnov ◽  
Dmytro Melnyk ◽  
Ovsiy Levbarg

The characteristics of the primary measurement standards of the volume gas flow rate at high pressure developed in various countries are considered. A hierarchical scheme for gas flow measuring instruments and a corresponding metrological traceability chain are presented. Described is a PVTt method, on which the primary standards of gas flow rate used in the USA, France, Japan, and Taiwan are based. The need to create in Ukraine primary measurement standards of gas flow rate at high pressure covering different parts of the total flow rate interval from 0,3 m3/h to 1800 m3/h at a pressure of 1 MPa to 5 MPa is substantiated. Metrological traceability of gas flow measurements is realized through a sequence of critical flow Venturi nozzles, which play a role of the reference flow rate material measures. The standards might be used to calibrate the primary reference Venturi nozzles of the most common 0,1 mm to 8 mm diameters. The characteristics and parameters of the standards are determined. By their metrological and technical characteristics, the standards will correspond to the state-of-the-art level. According to the programme of developing the measurement-standard facilities in Ukraine, in 2019 the primary standard PVTt-65 was created and work had started on the development of the primary standard PVTt-1800 and the working standard PE-5400. A detailed study of the metrological characteristics of the measurement standards will be the topic of further work.



Circulation ◽  
2021 ◽  
Vol 143 (Suppl_1) ◽  
Author(s):  
Tia S Lal ◽  
Sadie H Conway ◽  
Ruosha Li ◽  
William B Perkison ◽  
Feng Zhang ◽  
...  

Introduction: Evidence shows a positive correlation between work hour (WH) duration and incident diabetes (DM). However, little is known about the association between longitudinal WH patterns and the risk of incident DM. Hypothesis: We hypothesized that the greatest risk of DM would be observed in consistently long WH patterns and that age, sex, and ethnicity would modify the relationship between WH patterns and incident DM. Methods: We utilized a representative sample of 15,843 U.S. adults from the Panel Study of Income Dynamics who reported weekly WH for a minimum of five years between 1985-2017 and did not have a history of DM prior to reporting five years of WH data. Latent class linear mixed modeling was used to identify distinct longitudinal WH trajectory patterns. Multivariable logistic regression analyses were then used to examine the association between WH patterns and incident DM, with initial adjustments made for sex, age, ethnicity, education, income-to-needs ratio, and occupation. We also tested for statistical interactions between WH patterns and baseline age, sex, and ethnicity. Results: Over a mean follow-up of 17.5 years, four WH trends were identified: standard, full-time (61.1%), increasing (11.5%), quickly decreasing (11.3%), and gradually decreasing (16.1%). Age (interaction p=0.013), but not ethnicity nor sex, modified the association between WH patterns and incident DM. In age stratified analyses, adults aged 18-29 showed no significant association between WH patterns and DM. In adults aged 30-39, a gradually decreasing WH trend showed lower DM risk compared to those working standard hours (OR=0.59; 95% CI: 0.45 - 0.77). Among those ≥40 years, both quickly decreasing (OR=0.66; 95% CI: 0.50 - 0.87) and gradually decreasing (OR=0.45; 95% CI: 0.34 - 0.60) WH patterns were associated with lower risk of DM compared to those working standard hours. Conclusion: Compared to individuals working standard WH over many years, decreasing WH patterns were associated with a lower risk of incident DM.



2021 ◽  
Vol 12 (2) ◽  
pp. 1478-1483
Author(s):  
Elavarasi E ◽  
Binoy Varghese Cherian ◽  
Shanmugasundaram P ◽  
Vijey Aanandhi M

The work aims to develop an appropriate method for mexiletine with 35-65% recovery by the LPE method with efficient and selective efficacy of the IS and analyte for the analysis under Liquid Chromatography-Mass Spectrometry/ Mass Spectrometry. This method also reveals the bio-availability and bio-equivalence report for Internal Standard & working standard. At first, the selection of proper IS. The Internal standard should be structurally more similar to mexiletine. The selection of method plays a major role in which extraction procedure is done either by LPE or SPE. The selection of separation procedure should be either isocratic or gradient. Selection of column on bases separation principle of the compound. Since separation is the major principle for chromatography. Argon and Nitrogen Gas is used as carries with a flow-rate of 2L min. Temperature at 20°C, the pressure at 20psi. If the instrument doesn't show any peak or response in after loading sample, check the columns is an aqueous or reverse-phase and then submit the sample. Check all the solution and column and temperature and system stability before loading the sample. After loading the sample, must form calibration curve it must form linearity. The method found should possess the following parameters Specific & Selectivity, Precision & Accuracy. The work aims to develop a simple, elegant way for quantification of a molecule and the method determined will have recovery of 35-65% worldwide. This quantification will be further utilized in Full-Method Validation.



Author(s):  
Marwa B. Hannouf ◽  
Getachew Assefa ◽  
Malek B. Hannouf ◽  
Ian Gates

Abstract Purpose This study has two aims: first, propose the use of the driver-pressure-state-impact-response (DPSIR) framework to expand the normal focus of impact pathways in social life cycle assessment (S-LCA) on endpoint impacts to a systematic analysis to find links between the main sources of social issues and impacts; second, develop a new impact assessment method to quantify the lifetime health and economic outcomes associated with social subcategories, for the first time, using decision analytic models. Methods The DPSIR framework is mapped to the corresponding elements of the S-LCA context in relation to the social subcategories defined in the UNEP/SETAC methodological sheets. Next, a more robust approach is developed for cause-impact chains between social subcategories and impacts on human well-being based on decision-analytic models (decision trees and Markov models) using healthcare approaches and data. Finally, the health and economic consequences associated with social subcategories are quantified by using Quality Adjusted Life Years (QALYs) and costs based on medical literature and healthcare studies. Results and discussion The method was applied to the “working hours” social subcategory in Canada. The cause-effect chain is built using DPSIR framework in relation to the current social issue in Canada of working more than standard hours. Results of the decision analytic model show that working standard hours is more effective and cost-saving than working more than standard hours from the Canadian healthcare perspective. Working standard hours compared to more than standard hours led to an increase of 0.73 QALY and decrease in cost of $6702 per worker. Based on an estimated 2.4 million Canadian workers working more than standard hours, this resulted in a total gain of 1.7 million QALYs and saving of $16 billion overall. Using cost-effectiveness analysis, possible interventions at multiple entry points of the cause-effect chain within DPSIR framework are proposed to reduce the negative health impacts and associated costs of working more than standard hours in Canada. Conclusions Applying the method on other subcategories could help decision-makers establish the cause-effect aspects of the social performance of their product systems using a quantitative systematic analysis from a life cycle perspective. This approach supports corporate decision-makers to quantify social impacts associated with their product supply chains by calculating QALYs and healthcare costs of their socio-economic conditions enabling them to identify possible interventions to improve the social performance.



2021 ◽  
Author(s):  
Grzegorz Skrzypek ◽  
Philip Dunn

&lt;p&gt;The stable HCNOS isotope compositions can be reported in various ways depending on scientific domain and needs. The most common notations are 1) the isotope ratio of two stable isotopes; 2) isotope delta value, and 3) atom fraction of one or more of the isotopes. Frequently recalculations between these notations are required for certain applications, particularly when merging different data sets. All these recalculations require using the absolute isotope ratio for the zero points of the stable isotope delta scales (&lt;em&gt;R&lt;sub&gt;std&lt;/sub&gt;&lt;/em&gt;). However, several &lt;em&gt;R&lt;sub&gt;std&lt;/sub&gt;&lt;/em&gt; with very contrasting values have been proposed over time and there is no common agreement on which values should be used word-wide (Skrzypek and Dunn, 2020a).&lt;/p&gt;&lt;p&gt;Differences in the selection of &lt;em&gt;R&lt;sub&gt;std&lt;/sub&gt;&lt;/em&gt;value may lead to significant differences between different data sets recalculated from delta value to other notations. These differences in R&lt;sub&gt;std&lt;/sub&gt; have a significant influence also on the normalization of raw values but only when the normalization is conducted versus the working standard gas value. We proposed a user-friendly EasyIsoCalculator (http://easyisocalculator.gskrzypek.com) that allows recalculation between the main expressions of isotope compositions using various &lt;em&gt;R&lt;sub&gt;std&lt;/sub&gt;&lt;/em&gt; and aids for identification of potential inconsistencies in recalculations (Skrzypek and Dunn, 2020b).&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;Skrzypek G., Dunn P. 2020a. Absolute isotope ratios defining isotope scales used in isotope ratio mass spectrometers and optical isotope instruments. Rapid Communications in Mass Spectrometry 34: e8890.&lt;/p&gt;&lt;p&gt;Skrzypek G., Dunn P., 2020b. The recalculation of the stable isotope expressions for HCNOS &amp;#8211; EasyIsoCalculator. Rapid Communications in Mass Spectrometry 34: e8892.&lt;/p&gt;



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