Bioequivalence Testing Protocols

Durability is the most pressing issue preventing the efficient commercialization of polymer electrolyte membrane fuel cell (PEMFC) stationary and transportation applications. A big barrier to overcoming the durability limitations is gaining a better understanding of failure modes for user profiles. In addition, durability test protocols for determining the lifetime of PEMFCs are important factors in the development of the technology. These methods are designed to gather enough data about the cell/stack to understand its efficiency and durability without causing it to fail. They also provide some indication of the cell/stack’s age in terms of changes in performance over time. Based on a study of the literature, the fundamental factors influencing PEMFC long-term durability and the durability test protocols for both PEMFC stationary and transportation applications were discussed and outlined in depth in this review. This brief analysis should provide engineers and researchers with a fast overview as well as a useful toolbox for investigating PEMFC durability issues.

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A novel metric of reliability in pressure pain threshold measurement

Scientific Reports ◽

10.1038/s41598-021-86344-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bernard Liew ◽

Ho Yin Lee ◽

David Rügamer ◽

Alessandro Marco De Nunzio ◽

Nicola R. Heneghan ◽

...

Keyword(s):

Mixed Models ◽

Variance Components ◽

Pain Threshold ◽

Intraclass Correlation ◽

Pressure Pain Threshold ◽

Total Variance ◽

Lumbar Region ◽

Pressure Pain ◽

Pressure Algometer ◽

Testing Protocols

AbstractThe inter-session Intraclass Correlation Coefficient (ICC) is a commonly investigated and clinically important metric of reliability for pressure pain threshold (PPT) measurement. However, current investigations do not account for inter-repetition variability when calculating inter-session ICC, even though a PPT measurement taken at different sessions must also imply different repetitions. The primary aim was to evaluate and report a novel metric of reliability in PPT measurement: the inter-session-repetition ICC. One rater recorded ten repetitions of PPT measurement over the lumbar region bilaterally at two sessions in twenty healthy adults using a pressure algometer. Variance components were computed using linear mixed-models and used to construct ICCs; most notably inter-session ICC and inter-session-repetition ICC. At 70.1% of the total variance, the source of greatest variability was between subjects ($${\sigma }_{subj}^{2}$$ σ subj 2 = 222.28 N2), whereas the source of least variability (1.5% total variance) was between sessions ($${\sigma }_{sess}^{2}$$ σ sess 2 = 4.83 N2). Derived inter-session and inter-session-repetition ICCs were 0.88 (95%CI: 0.77 to 0.94) and 0.73 (95%CI: 0.53 to 0.84) respectively. Inter-session-repetition ICC provides a more conservative estimate of reliability than inter-session ICC, with the magnitude of difference being clinically meaningful. Quantifying individual sources of variability enables ICC construction to be reflective of individual testing protocols.

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Methods, Protocols, Guidance and Standards for Performance Evaluation for Point-of-Use Water Treatment Technologies: History, Current Status, Future Needs and Directions

Water ◽

10.3390/w13081094 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1094

Author(s):

Emily S. Bailey ◽

Nikki Beetsch ◽

Douglas A. Wait ◽

Hemali H. Oza ◽

Nirmala Ronnie ◽

...

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Enteric Bacteria ◽

Current Status ◽

Household Water Treatment ◽

Produce Water ◽

Point Of Use ◽

Treatment Technologies ◽

Injury And Repair ◽

Testing Protocols

It is estimated that 780 million people do not have access to improved drinking water sources and approximately 2 billion people use fecally contaminated drinking water. Effective point-of-use water treatment systems (POU) can provide water with sufficiently reduced concentrations of pathogenic enteric microorganisms to not pose significant health risks to consumers. Household water treatment (HWT) systems utilize various technologies that physically remove and/or inactivate pathogens. A limited number of governmental and other institutional entities have developed testing protocols to evaluate the performance of POU water treatment systems. Such testing protocols are essential to documenting effective performance because inferior and ineffective POU treatment technologies are thought to be in widespread use. This critical review examines specific practices, procedures and specification of widely available POU system evaluation protocols. Testing protocols should provide standardized and detailed instructions yet be sufficiently flexible to deal with different treatment technologies, test microbe priorities and choices, testing facility capabilities and public health needs. Appropriate infectivity or culture assays should be used to quantify test enteric bacteria, viruses and protozoan parasites, or other appropriate surrogates or substitutes for them, although processes based on physical removal can be tested by methods that detect microbes as particles. Recommendations include further research of stock microbe production and handling methods to consistently yield test microbes in a realistic state of aggregation and, in the case of bacteria, appropriately physiologically stressed. Bacterial quantification methods should address the phenomenon of bacterial injury and repair in order to maximally recover those that are culturable and potentially infectious. It is only with harmonized national and international testing protocols and performance targets that independent and unbiased testing can be done to assure consumers that POU treatment technologies are able to produce water of high microbial quality and low health risk.

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