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Context: Method engineering approaches are often based on the assumption that method users are able to explicitly express their situational method requirements. Similar to systems requirements, method requirements are often vague ...
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Context: Method engineering approaches are often based on the assumption that method users are able to explicitly express their situational method requirements. Similar to systems requirements, method requirements are often vague and hard to explicate. In this paper we address the issue of involving method users early in method configuration. This is done through borrowing ideas from user-centered design and prototyping, and implementing them on the method engineering layer.Objective: We design a computerized tool, MC Sandbox, to capture method requirements through the use of method-user-centered method configuration, hence bridging the gap between systems developers' and method engineers' understanding of and expectations on a situational method.Method: The research method adopted can be characterized as multi-grounded action research. Our implementation of multi-grounded action research follows the traditional 'canonical' action research method, which has cycles of diagnosing, action planning, action taking, evaluating, and specifying learning. The research project comprised three such action research cycles where 10 action cases were performed. Results: MC Sandbox has proven useful in eliciting and negotiating method requirements in a continuously ongoing dialog between the method users and the method engineers during configuration workshops. The results also show that the method engineer role rotated among the systems developers and that they were indeed committed to the negotiated methods during the systems development projects. Conclusion: It is possible for method users to actively participate and construct suitable situational methods if they are provided with appropriate high-level modelling concepts, such as method components,configuration packages and configuration templates. This way, the project members' understanding of the current development practice develops incrementally, both in terms of understanding the needs and available method support. In addition, both method requirements and commitments are made explicit, which are important aspects when working with method configuration from a collaboration point of vicw.
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Ketorolac tromethamine is a potent nonsteroidal anti-inflammatory drug that is widely used in the treatment of moderate to severe pain. A new method was developed and validated for quantifying ketorolac (the free acid of the trome...
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Ketorolac tromethamine is a potent nonsteroidal anti-inflammatory drug that is widely used in the treatment of moderate to severe pain. A new method was developed and validated for quantifying ketorolac (the free acid of the tromethamine salt) in human plasma by high-performance thin-layer chromatography. The stationary phase was silica gel 60, and the composition of the mobile phase was n-butanol-chloroform-acetic acid-ammonium hydroxide-water (9 + 3 + 5 + 1 + 2, v/v). The densitometric analysis of ketorolac was performed at 323 nm. The method was validated for precision (repeatability and reproducibility), accuracy, and sensitivity. Repeatability was 10.11% [coefficient of variation (CV)] and reproducibility was 12.18% (CV) as the maximum variation. Accuracy was determined at 3 different concentration levels, and results were within +/- 15% of the predetermined range. Data were fitted by a linear mathematical function (linear regression). The calibration graph was linear in the range of 200-2000 ng/mL. Average recovery was 73.67%. The method proved to be accurate, precise, and sensitive for the ketorolac tromethamine quantification.
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A selective, precise, and accurate high-performance thin-layer chromatographic (HPTLC) method has been proposed for the analysis of conessine in Holarrhena antidysenterica. The method involves visible densitometric evaluation of c...
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A selective, precise, and accurate high-performance thin-layer chromatographic (HPTLC) method has been proposed for the analysis of conessine in Holarrhena antidysenterica. The method involves visible densitometric evaluation of conessine resolving it by HPTLC on aluminium-based silica gel plates. For visible densitometric evaluation, peak areas were recorded at 520 nm after the resolved bands were derivatized with Dragendorff's reagent and then sprayed with a 10% solution of aqueous sodium nitrite which resulted in reddish brown color. The correlation between the concentration and area was found to be linear within the range of 10 to 60 ng/spot. The method was validated for precision (interday and intraday), repeatability, and accuracy. Mean recovery for conessine was 98.34-100.25%. The method was applied for the quantitation of conessine in Kurchi. The proposed HPTLC method was found to be precise, specific, sensitive, and accurate and can be used for routine analysis of Kurchi.
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Sibutramine hydrochloride monohydrate, chemically 1-(4-chlorophenyl)-N,N-dimethyl-alpha-(2-methylpropyl) hydrochloride monohydrate (SB center dot HCl center dot H2O), was approved by the U.S. Food and Drug Administration for the t...
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Sibutramine hydrochloride monohydrate, chemically 1-(4-chlorophenyl)-N,N-dimethyl-alpha-(2-methylpropyl) hydrochloride monohydrate (SB center dot HCl center dot H2O), was approved by the U.S. Food and Drug Administration for the treatment of obesity. The objective of this study was to develop, validate, and compare methods using UV-derivative spectrophotometry (UVDS) and reversed-phase high-performance liquid chromatography (HPLC) for the determination of SB center dot HCl center dot H2O in pharmaceutical drug products. The UVDS and HPLC methods were found to be rapid, precise, and accurate. Statistically, there was no significant difference between the proposed UVDS and HPLC methods. The enantiomeric separation of SB was obtained on an alpha-1 acid glycoprotein column. The R- and S-sibutramine were eluted in < 5 min with baseline separation of the chromatographic peaks (alpha = 1.9 and resolution = 1.9).
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A simple, precise, and accurate isocratic reversed-phase (RP) stability-indicating column high-performance liquid chromatographic (HPLC) assay method was developed and validated for determination of nebivolol in solid pharmaceutic...
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A simple, precise, and accurate isocratic reversed-phase (RP) stability-indicating column high-performance liquid chromatographic (HPLC) assay method was developed and validated for determination of nebivolol in solid pharmaceutical dosage forms. Isocratic RP-HPLC separation was achieved on a Phenomenex Luna C8 (2) column (250 mm x 4.6 mm id, 5 pm particle size) using mobile phase composed of acetonitrile-pH 3.5 phosphate buffer (35 + 65, v/v) at a flow rate of 1.0 mL/min, and detection was performed at 280 nm using a photodiode array detector. The drug was subjected to oxidation, hydrolysis, photolysis, and heat to apply stress conditions. The method was validated for specificity, linearity, precision, accuracy, robustness, and solution stability. The method was linear in the drug concentration range of 40-160 mu g/mL with a correlation coefficient of 0.9999. The repeatability relative standard deviation (RSD) for 6 samples was 0.69%, and the intermediate precision (RSD) for 6 samples was 1.39%. The accuracy (recovery) was between 98.57 and 99.55%. Degradation products produced as a result of stress studies did not interfere with detection of nebivolol, and the assay can thus be considered stability-indicating.
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Purpose - After the initial life (which coincides with the origins of social research in the 1850s, and lasts until 1940s), mixed methods revive at the beginning of 1970s. However, this second life (or renaissance) receives the de...
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Purpose - After the initial life (which coincides with the origins of social research in the 1850s, and lasts until 1940s), mixed methods revive at the beginning of 1970s. However, this second life (or renaissance) receives the deleterious imprinting of quantitative methods. In fact, some of the old positivist assumptions are still reproduced and active in most of mixed methods research. This imprinting is traceable in the ambiguity (and purposive semantic stretching) of the term "qualitative": from the 1990s, it encompasses almost everything (even approaches considered positivistic in the 1950s!). Whereby the semantical extension of the term "qualitative" has become a sort of Trojan horse for a new legitimation of many quantitative and positivist researchers: a great swindle. Today "qualitative" is nonsense and acts as a bug, which muddies the qualitative-quantitative debate. For this reason, it would be better to remove the bug (i.e. to discharge the term "qualitative" from the language of social research and methodology), reset and start over from the level of specific research methods, considering carefully and balancing their diversity before mixing them The purpose of this paper is to outline two (complementary) ways of integration of methods ("mixed" and "merged"), arguing that "merged" methods realize a higher integration than "mixed" methods, because the former overcome some weaknesses of the latter. Design/methodology/approach - A semantic and pragmatic analysis of the term "qualitative." Findings - In social and behavioral sciences, the second life of mixed methods has been heavily affected by old positivist and quantitative assumptions. Research limitations/implications - The term "qualitative" should be discharged from the language of social research and methodology. Practical implications - The coveted integration in "mixed" methods, could be better pursed through "merged" methods. Social implications - Disentangling the strands of a debate (the qualitative-quantitative one) become muddy. Originality/value - An alternative framework, to interpret the mixed methods history and their recent developments, has been proposed.
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An analysis of numerical methods for solving algebraic and transcendental equations in terms of speed is performed. In contrast to the reliable bisection method, the well-known parabolic methods by Muller, Brent, and Ridders have ...
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An analysis of numerical methods for solving algebraic and transcendental equations in terms of speed is performed. In contrast to the reliable bisection method, the well-known parabolic methods by Muller, Brent, and Ridders have been determined to have higher speed, but do not always ensure the specified accuracy of the solution. Based on the data obtained, an improved parabolic method that guarantees accuracy confirmed by computational experiment is developed. This proposed method combines the quadratic speed of parabolic approaches and the ability to provide stable convergence to the solution for slowly varying functions inherent to the bisection method. (C) 2021 Elsevier Inc. All rights reserved.
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Bovine blood, cell, tissue, and organ are used as raw materials for manufacturing biologics Such Lis biopharmaceuticals, tissue-engineered products, and cell therapy. Manufacturing processes for the biologics have the risk of vira...
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Bovine blood, cell, tissue, and organ are used as raw materials for manufacturing biologics Such Lis biopharmaceuticals, tissue-engineered products, and cell therapy. Manufacturing processes for the biologics have the risk of viral contamination. Therefore viral validation is essential in ensuring the safety of the products. Bovine parvovirus (BPV) is one of the common bovine pathogens and has widely been known as a possible contaminant of biologics. In order to establish the validation system for the BPV safety of biologics, a real-time PCR method was developed for quantitative detection of BPV contamination in raw materials, manufacturing processes, and final products. Specific primers for amplification of BPV DNA were selected, and BPV DNA was quantified by use of SYBR Green 1. The sensitivity of the assay was caculated to be 1.3 x 10(-1) TCID50/mL. The real-time PCR method was validated to be reproducible and very specific to BPV. The established real-time PCR assay was Successfully applied to the validation of Chinese hamster ovary (CHO) cell artificially infected with BPV. BPV DNA could be quantified in CHO cell as well as culture supernatant. Also the real-time PCR assay Could detect 1.3 x 10(0) TCID50/mL of BPV artificially contaminated in bovine collagen. The overall results indicated that this rapid, specific, sensitive, and robust assay can be reliably used for quantitative detection of BPV contamination during manufacture of biologics.
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A simple, sensitive, and rapid liquid chromatographic/tandem mass spectrometric (LC/MS/MS) method, using electrospray ionization, was developed and validated to quantify trimetazidine in human plasma using propranolol hydrochlorid...
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A simple, sensitive, and rapid liquid chromatographic/tandem mass spectrometric (LC/MS/MS) method, using electrospray ionization, was developed and validated to quantify trimetazidine in human plasma using propranolol hydrochloride as an internal standard (IS). Samples were prepared by solid-phase extraction and analyzed without drying and reconstitution. The analyte and IS were chromatographed on a C18 reversed-phase column under isocratic conditions using 2 mM ammonium acetate (pH 3.5) -acetonitrile (40 + 60, v/v) as the mobile phase with a run time of 2.0 min. Quantitation was done on a triple-quadrupole mass analyzer API-3000, equipped with turbo ion spray interface and operating in multiple reaction monitoring mode to detect parent -> product ion (mlz 267.2 -> 181.4) transition. The method was validated for sensitivity, accuracy and precision, linearity, recovery, matrix effect, and stability. Linearity in plasma was observed over the concentration range of 1.5-300 ng/mL. Lower limit of quantification achieved was 1.5 ng/mL with precision < 10% using 10 mu L injection volume. The mean relative recovery of analyte (97.36%) and IS (99.93%) was consistent and reproducible. Interbatch and intrabatch precision was < 8.0% and the accuracy determined was within +/- 8% in terms of relative error.
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Telescopes are much more expensive than astronomers, so it is essential to minimize required sample sizes by using the most data-efficient statistical methods possible. However, the most commonly used model-independent techniques ...
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Telescopes are much more expensive than astronomers, so it is essential to minimize required sample sizes by using the most data-efficient statistical methods possible. However, the most commonly used model-independent techniques for finding the relationship between two variables in astronomy are flawed. In the worst case they can lead without warning to subtly yet catastrophically wrong results, and even in the best case they require more data than necessary. Unfortunately, there is no single best technique for nonparametric regression. Instead, we provide a guide for how astronomers can choose the best method for their specific problem and provide a python library with both wrappers for the most useful existing algorithms and implementations of two new algorithms developed here.
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