5.1 Overview of Measurement System—Relative intensity measurements made by widefield epifluorescence microscopy are used as part of cell-based assays to quantify attributes such as the abundance of probe molecules (see ASTM F2997), fluorescently labeled antibodies, or fluorescence protein reporter molecules. The general procedure for quantifying relative intensities is to acquire digital images, then to perform image analysis to segment objects and compute intensities. The raw digital images acquired by epifluorescence microscopy are not typically amenable to relative intensity quantification because of the factors listed in 4.2. This guide offers a checklist of potential sources of bias that are often present in fluorescent microscopy images and suggests approaches for storing and normalizing raw image data to assure that computations are unbiased.5.2 Areas of Application—Widefield fluorescence microscopy is frequently used to measure the location and abundance of fluorescent probe molecules within or between cells. In instances where RIM comparisons are made between a region of interest (ROI) and another ROI, accurate normalization procedures are essential to the measurement process to minimize biased results. Example use cases where this guidance document may be applicable include:5.2.1 Characterization of cell cycle distribution by quantifying the abundance of DNA in individual cells (1).75.2.2 Measuring the area of positively stained mineralized deposits in cell cultures (ASTM F2997).5.2.3 Quantifying the spread area of fixed cells (ASTM F2998).5.2.4 Determining DNA damage in eukaryotic cells using the comet assay (ASTM E2186).5.2.5 The quantitation of a secondary fluorescent marker that provides information related to the genotype, phenotype, biological activity, or biochemical features of a colony or cell (ASTM F2944).1.1 This guidance document has been developed to facilitate the collection of microscopy images with an epifluorescence microscope that allow quantitative fluorescence measurements to be extracted from the images. The document is tailored to cell biologists that often use fluorescent staining techniques to visualize components of a cell-based experimental system. Quantitative comparison of the intensity data available in these images is only possible if the images are quantitative based on sound experimental design and appropriate operation of the digital array detector, such as a charge coupled device (CCD) or a scientific complementary metal oxide semiconductor (sCMOS) or similar camera. Issues involving the array detector and controller software settings including collection of dark count images to estimate the offset, flat-field correction, background correction, benchmarking of the excitation lamp and the fluorescent collection optics are considered.1.2 This document is developed around epifluorescence microscopy, but it is likely that many of the issues discussed here are applicable to quantitative imaging in other fluorescence microscopy systems such as fluorescence confocal microscopy. This guide is developed around single-color fluorescence microscopy imaging or multi-color imaging where the measured fluorescence is spectrally well separated.1.3 Fluorescence intensity is a relative measurement and does not in itself have an associated SI unit. This document does discuss metrology issues related to relative measurements and experimental designs that may be required to ensure quantitative fluorescence measurements are comparable after changing microscope, sample, and lamp configurations.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1  Zeolites Y and X, particularly for catalyst and adsorbent applications, are a major article of manufacture and commerce. Catalysts and adsorbents comprising these zeolites in various forms plus binder and other components have likewise become important. Y-based catalysts are used for fluid catalytic cracking (FCC) and hydrocracking of petroleum, while X-based adsorbents are used for desiccation, sulfur compound removal, and air separation.4.2 The unit cell dimension of a freshly synthesized faujasite-type zeolite is a sensitive measure of composition which, among other uses, distinguishes between the two synthetic faujasite-type zeolites, X and Y. The presence of a matrix in a Y-containing catalyst precludes determination of the zeolite framework composition by direct elemental analysis.4.3 Users of the test method should be aware that the correlation between framework composition and unit cell dimension is specific to a given cation form of the zeolite. Steam or thermal treatments, for example, may alter both composition and cation form. The user must therefore determine the correlation that pertains to his zeolite containing samples.3 In addition, one may use the test method solely to determine the unit cell dimension, in which case no correlation is needed.4.4 Other crystalline components may be present in the sample whose diffraction pattern may cause interference with the selected faujasite-structure diffraction peaks. If there is reason to suspect the presence of such components, then a full diffractometer scan should be obtained and analyzed to select faujasite-structure peaks free of interference.1.1 This test method covers the determination of the unit cell dimension of zeolites having the faujasite crystal structure, including synthetic Y and X zeolites, their modifications such as the various cation exchange forms, and the dealuminized, decationated, and ultra stable forms of Y. These zeolites have cubic symmetry with a unit cell parameter usually within the limits of 24.2 and 25.0 Å (2.42 and 2.50 nm).1.2 The samples include zeolite preparation in the various forms, and catalysts and adsorbents containing these zeolites. The zeolite may be present in amounts as low as 5 %, such as in a cracking catalyst.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This specification covers preformed expansion joint fillers made from closed-cell polyolefin materials having suitable compressibility and nonextruding characteristics.1.1.1 Type I, closed-cell polyethylene or blended polyethylene.1.2 These joint fillers are intended for use in concrete pavements in full-depth joints. There are several variations in size. A typical size measures 0.5 in. (12.7 mm) in thickness, 4.0 in. (101.6 mm) in width, and 10 ft (3.048 m) in length and will relieve stress or avoid potential distress in adjacent structures or pavements.1.3 The values stated in inch-pound units are to be regarded as the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This guide is limited to procedures used solely for the testing of substances to determine their mutagenicity and does not apply to other methods and uses such as exploring mechanisms of mutation.Recent evidence suggests that this assay measures a dual genetic end point; therefore, some discussion of the relationships between mammalian cell mutagenicity testing results and the results observed both in pure gene mutational assays and in cytogenetic assays is necessary. However, it is not the intent of this guide to discuss other relationships between this mammalian cell mutagenicity testing results and the results observed in other tests for mutagenicity and carcinogenicity.1.1 The purpose and scope of this guide is to present background material and to establish criteria by which protocols and procedures for conducting the L5178Y/TK+/−-3.7.2C mouse lymphoma mutagenicity assay (commonly referred to as the mouse lymphoma assay, (MLA)) can be properly understood and evaluated. This guide is also intended to aid researchers and others to gain a better understanding of the critical elements involved with mammalian cell mutagenicity testing. More specifically, this guide is intended to provide for researchers the accomplishment of the following goals:1.1.1 Provide an understanding of the critical procedures (steps) in the performance of this mammalian cell mutagenicity test.1.1.2 Provide generalized criteria by which researchers can evaluate if they are properly performing, utilizing, and interpreting this assay.1.1.3 Provide criteria by which individuals responsible for evaluating MLA data can determine if the experiments have been properly performed and interpreted.1.1.4 Provide a basis from which new procedures and developments in testing procedures can be evaluated.1.1.5 Provide an understanding of the types of genetic damage (that is, gene and chromosome mutation) that may be detected in this mammalian cell mutagenicity test.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

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5.1 There are no reproducible standardized protocols for preparing specimens used to evaluate the microbicidal efficacy of non-chemical treatments such as ultraviolet (UV), highenergy electron beam, or other forms of non-chemical antimicrobial technologies.5.2 Conventional protocols for applying bioburdens to carriers (see Test Method E2197) cause cells to stack upon one another, thereby creating multiple cell layers in which cells in layers closer to the carrier are masked by cells in overlying layers, which makes relative comparison of different non-chemical antimicrobial treatments more difficult.5.3 Steel and other metal carriers have asperities that can shield a percentage of the applied cells from direct exposure to electromagnetic irradiation.5.4 The combined effects of 5.2 and 5.3 confound determination of the microbicidal effect of electromagnetic irradiation on test specimens.5.5 The practice addresses these two confounding factors by:5.5.1 Using glass microscope slides – the surfaces of which are asperity-free – as carriers.5.5.2 Reliably depositing bacterial cells onto the carrier as a monolayer.5.6 The resulting specimen ensures that all microbes deposited onto the carrier are exposed equally to the irradiation source thereby ensuring that the only variables are the controlled ones – starting inoculum concentration, wavelength (λ – in nm), exposure time(s), and resulting energy dose (J).1.1 This practice provides a protocol for creating bacterial cell monolayers on a flat surface.1.2 The cultures used and culture preparation steps in this Practice are similar to AOAC Method 961.02 and US EPA MB-06. However, test bacteria are applied to the carrier using an automated deposition device (6.2) rather than as a suspension droplet.1.3 The carrier inspection protocol is similar to US EPA MB-03 except that carrier surfaces are inspected microscopically rather than visually, unaided.1.4 A monolayer of cells eliminates the confounding effect caused by the shadowing effect of outer layers of bacteria stacked upon other bacteria on test specimens – thereby attenuating directed energy beams (that is, ultraviolet light, high-energy electron beams) before they can reach underlying cells.1.5 An asperity-free surface eliminates the shadowing effect of specimen surface topology that can block direct exposure of target bacteria to non-chemical antimicrobial treatments.1.6 This practice provides a reproducible target microbe and surface specimen to minimize specimen variability within and between testing facilities. This facilitates direct data comparisons among various non-chemical antimicrobial technologies.1.6.1 Antimicrobial pesticides used in clinical and industrial applications are expected to overcome shadowing effects. However, this practice meets a need for a protocol that facilitates relative comparisons among non-chemical antimicrobial treatments.1.6.2 This practice is not intended to satisfy or replace existing test requirements for liquid chemical antimicrobial treatments (for example Test Methods E1153 and E2197) or established regulatory agency performance standards such as US EPA MB-06.1.7 This practice was validated using Staphylococcus aureus (ATCC 6538) and Pseudomonas aeruginosa (ATCC 15442) using a protocol based on AOAC Method 961.02. If other cultures are used, the suitability of this practice must be confirmed by inspecting prepared surfaces, by using scanning electron microscopy (SEM) or comparable high-resolution microscopy.1.8 The specimens prepared in accordance with this practice are not meant to simulate end-use conditions.1.8.1 Non-chemical technologies are only to be used on visibly clean, non-porous surfaces. Consequently, a soil load is not used.1.9 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The number and distribution of viable and non-viable cells within, or on the surface of, a biomaterial scaffold is one of several important characteristics that may determine in vivo product performance of cell/biomaterial constructs (see 5.7); therefore, there is a need for standardized test methods to quantify cell viability.5.2 There are a variety of static and dynamic methods to seed cells on scaffolds, each with different cell seeding efficiencies. In general, static methods such as direct pipetting of cells onto scaffold surfaces have been shown to have lower cell seeding efficiencies than dynamic methods that push cells into the scaffold interior. Dynamic methods include: injection of cells into the scaffold, cell seeding on biomaterials contained in spinner flasks or perfusion chambers, or seeding that is enhanced by the application of centrifugal forces. The methods described in this guide can assist in establishing cell seeding efficiencies as a function of seeding method and for standardizing viable cell numbers within a given methodology.5.3 As described in Guide F2315, thick scaffolds or scaffolds highly loaded with cells lead to diffusion limitations during culture or implantation that can result in cell death in the center of the construct, leaving only an outer rim of viable cells. Spatial variations of viable cells such as this may be quantified using the tests within this guide. The effectiveness of the culturing method or bioreactor conditions on the viability of the cells throughout the scaffold can also be evaluated with the methods described in this guide.5.4 These test methods can be used to quantify cells on non-porous or within porous hard or soft 3-D synthetic or natural-based biomaterials, such as ceramics, polymers, hydrogels, and decellularized extracellular matrices. The test methods also apply to cells seeded on porous coatings.5.5 Test methods described in this guide may also be used to distinguish between proliferating and non-proliferating viable cells. Proliferating cells proceed through the DNA synthesis (S) phase and the mitosis (M) phase to produce two daughter cells. Non-proliferating viable cells are in some phase of the cell cycle, but are not necessarily proceeding through the cell cycle culminating in proliferation.5.6 Viable cells may be under stress or undergoing apoptosis. Assays for evaluating cell stress or apoptosis are not addressed in this guide.5.7 While cell viability is an important characteristic of a TEMP, the biological performance of a TEMP is dependent on additional parameters. Additional tests to evaluate and confirm the cell identity, protein expression, genetic profile, lineage progression, extent of differentiation, activation status, and morphology are recommended.5.8 The main focus of this document is not scaffold toxicity or the toxicity of the scaffold raw materials. This document is meant to address the situation where a scaffold that is thought to be cytocompatible is cultured with cells and the user desires to assess the viability of cells within the construct. Prior to conducting the tests described herein, the raw materials used to make the scaffold should be assessed as described in Practice F748. This testing may include assessment of the release of toxic leachables from the raw materials.5.9 Methods that remove the cells from a 3-D scaffold may reduce the cell number and viability due to the manipulation required.5.10 Some scaffold constructs may prevent reliable measurements of cell viability within the scaffolds using the methods described herein. Scaffolds may limit diffusion of assay components into and out of the scaffolds. This is especially problematic for methods that require dyes to penetrate into the scaffold, that require detergents or other cell-lysing agents to diffuse into the construct, that require lysed-cell components to diffuse out of the constructs, or that require assay reactants to diffuse into or out of the scaffold. Diffusion in scaffolds and assay results may also be affected by dense cell populations in scaffolds, the generation of tissue-like structures by the cells within the scaffold, and the presence of cell-generated extracellular matrix (ECM) in the scaffold. The formation of tight junctions between cells and cell-ECM interactions may also limit diffusion, especially in the case of hard tissues such as bone.5.11 Assay results may be affected by interactions between assay components and the scaffold. Assay components may adsorb to the surface of the scaffold which would affect their participation in the assay and the resulting assay signal. Biochemical interactions between the scaffold and assay components may cause activation or inhibition of the assay chemistries.5.12 Different cell viability tests may measure different things and may not agree with one another. A large variety of cell viability assays have been developed to measure different aspects of the cell death process. Some of the common measurements include penetration of dyes into the cell, cell metabolic activity, cellular ATP, and leakage of intracellular components out of the cell. Each of these phenomena are related to the state of cell viability in different ways, and may represent different attributes of the cell death process. The mechanism of cell death will also affect the results for these different types of viability measurements. Necrosis, oxygen depravation, starvation, chemical toxicity, apoptosis, anoikis, and mechanical damage represent some of the causes of cell death. Each of these mechanisms may have different effects on the different aspects of cell death that are measured by cell viability assays.1.1 This guide is a resource of cell viability test methods that can be used to assess the number and distribution of viable and non-viable cells within porous and non-porous, hard or soft biomaterial scaffolds, such as those used in tissue-engineered medical products (TEMPs).1.2 In addition to providing a compendium of available techniques, this guide describes materials-specific interactions with the cell assays that can interfere with accurate cell viability analysis, and includes guidance on how to avoid or account for, or both, scaffold material/cell viability assay interactions.1.3 These methods can be used for 3-D scaffolds containing cells that have been cultured in vitro or for scaffold/cell constructs that are retrieved after implantation in living organisms.1.4 This guide does not propose acceptance criteria based on the application of cell viability test methods.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice is useful for assessing cytotoxic potential both when evaluating new materials or formulations for possible use in medical applications, and as part of a quality control program for established medical materials and medical devices.4.2 This practice assumes that assessment of cytotoxicity potential provides one method for predicting the potential for cytotoxic or necrotic reactions to medical materials and devices during clinical applications to humans. In general, cell culture testing methods have shown good correlation with animal assays when only chemical toxicities are being considered.NOTE 1: The results obtained using this method may not predict in vivo behavior which can be influenced by multiple factors such as those arising from site of application or physical properties that may result from design and fabrication.4.3 This cell culture test method is suitable for adoption in specifications and standards for materials for use in the construction of medical devices that are intended to have direct contact with tissue, tissue fluids, or blood. However, care should be taken when testing materials that are absorbable, include an eluting or degradable coating, are liquid or gelatinous in nature, are irregularly shaped solid materials, or have a high density or mass, to make sure that the method is applicable. If leachables from the test sample are capable of diffusing through the agar layer, agarose-based methods such as Test Method F895 may be considered as an alternate method, depending on sample characteristics, or in cases where investigators wish to further evaluate the cytotoxic response of cells underlying the test sample.1.1 This practice covers a reference method of direct contact cell culture testing which may be used in evaluating the cytotoxic potential of materials for use in the construction of medical materials and devices.1.2 This practice may be used either directly to evaluate materials or as a reference against which other cytotoxicity test methods may be compared.1.3 This is one of a series of reference test methods for the assessment of cytotoxic potential, employing different techniques.1.4 Assessment of cytotoxicity is one of several tests employed in determining the biological response to a material, as recommended in Practice F748.1.5 The L-929 cell line was chosen because it has a significant history of use in assays of this type. This is not intended to imply that its use is preferred; only that the L-929 is a well characterized, readily available, established cell line that has demonstrated reproducible results in several laboratories.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The purpose of this guide is to provide general guidelines for the design and operation of hot cell equipment to ensure longevity and reliability throughout the period of service.4.2 It is intended that this guide record the general conditions and practices that experience has shown is necessary to minimize equipment failures and maximize the effectiveness and utility of hot cell equipment. It is also intended to alert designers to those features that are highly desirable for the selection of equipment that has proven reliable in high radiation environments.4.3 This guide is intended as a supplement to other standards, and to federal and state regulations, codes, and criteria applicable to the design of equipment intended for hot cell use.4.4 This guide is intended to be generic and to apply to a wide range of types and configurations of hot cell equipment.1.1 Intent: 1.1.1 The intent of this guide is to provide general design and operating considerations for the safe and dependable operation of remotely operated hot cell equipment. Hot cell equipment is hardware used to handle, process, or analyze nuclear or radioactive material in a shielded room. The equipment is placed behind radiation shield walls and cannot be directly accessed by the operators or by maintenance personnel because of the radiation exposure hazards. Therefore, the equipment is operated remotely, either with or without the aid of viewing.1.1.2 This guide may apply to equipment in other radioactive remotely operated facilities such as suited entry repair areas, canyons or caves, but does not apply to equipment used in commercial power reactors.1.1.3 This guide does not apply to equipment used in gloveboxes.1.2 Applicability: 1.2.1 This guide is intended for persons who are tasked with the planning, design, procurement, fabrication, installation, or testing of equipment used in remote hot cell environments.1.2.2 The equipment will generally be used over a long-term life cycle (for example, in excess of two years), but equipment intended for use over a shorter life cycle is not excluded.1.2.3 The system of units employed in this standard is the metric unit, also known as SI Units, which are commonly used for International Systems, and defined by IEEE/ASTM SI 10: American National Standard for Use of the International System of Units (SI): The Modern Metric System.1.3 Caveats: 1.3.1 This guide does not address considerations relating to the design, construction, operation, or safety of hot cells, caves, canyons, or other similar remote facilities. This guide deals only with equipment intended for use in hot cells.1.3.2 Specific design and operating considerations are found in other ASTM documents.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Although the test method can be used for assessment of the bioactivity of crude preparations of rhBMP-2, it has only been validated for use with highly pure (>98 % by weight protein purity) preparations of rhBMP-2.1.1 This test method describes the method used and the calculation of results for the determination of the in-vitro biological activity of rhBMP-2 using the mouse stromal cell line W-20 clone 17 (W-20-17). This clone was derived from bone marrow stromal cells of the W++ mouse strain.21.2 This test method (assay) has been qualified and validated based upon the International Committee on Harmonization assay validation guidelines3 (with the exception of interlaboratory precision) for the assessment of the biological activity of rhBMP-2. The relevance of this in-vitro test method to in-vivo bone formation has also been studied. The measured response in the W-20 bioassay, alkaline phosphatase induction, has been correlated with the ectopic bone-forming capacity of rhBMP-2 in the in-vivo Use Test (UT). rhBMP-2 that was partially or fully inactivated by targeted peracetic acid oxidation of the two methionines was used as a tool to compare the activities. Oxidation of rhBMP-2 with peracetic acid was shown to be specifically targeted to the methionines by peptide mapping and mass spectrometry. These methionines reside in a hydrophobic receptor binding pocket on rhBMP-2. Oxidized samples were compared alongside an incubation control and a native control. The 62, 87, 98, and 100 % oxidized samples had W-20 activity levels of 62, 20, 7, and 5 %, respectively. The incubation and native control samples maintained 100 % activity. Samples were evaluated in the UT and showed a similar effect of inactivation on bone-forming activity. The samples with 62 % and 20 % activity in the W-20 assay demonstrated reduced levels of bone formation, similar in level with the reduction in W-20 specific activity, relative to the incubation control. Little or no ectopic bone was formed in the 7 and 5 % active rhBMP-2 implants.1.3 Thus, modifications to the rhBMP-2 molecule in the receptor binding site decrease the activity in both the W-20 and UT assays. These data suggest that a single receptor binding domain on rhBMP-2 is responsible for both in-vitro and in-vivo activity and that the W-20 bioassay is a relevant predictor of the bone-forming activity of rhBMP-2.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification covers the general and design requirements for two types of cell-type ovens based on their rates of ventilation, for determining loss in weight or changes in properties of materials on heating at elevated temperatures. This specification takes into account the fact that chamber geometry, rate of ventilation, and temperature each affect the rate of loss of volatile constituents from a material, or the rate of change in other properties. Hence, this oven is recommended whenever the results are dependent on the time and temperature of heating, the amount of ventilation, or both.1.1 This specification covers the general requirements of a cell-type oven with controlled rates of ventilation for determining loss in weight or changes in properties of materials on heating at elevated temperatures. These specifications take into account the fact that chamber geometry, rate of ventilation, and temperature each affect the rate of loss of volatile constituents from a material, or the rate of change in other properties. This oven is recommended whenever the results are dependent on the time and temperature of heating, the amount of ventilation, or both. It is assumed that specific requirements such as specimen shape and dimensions, rate of ventilation, time, and temperature will be included in the applicable material specifications or test methods.NOTE 1: Ovens meeting these specifications have been found useful for determination of plasticizer loss in plastics, and for controlled aging of elastomers and plastics.1.2 The values stated in inch-pound units are to be regarded as the standard.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Rigid gas-filled closed-cell foam insulations include all cellular plastic insulations which rely on a blowing agent (or gas), other than air, for thermal resistance values. At the time of manufacture, the cells of the foam usually contain their highest percentage of blowing agent and the lowest percentage of atmospheric gases. As time passes, the relative concentrations of these gases change due primarily to diffusion. This results in a general reduction of the thermal resistance of the foam due to an increase in the thermal conductivity of the resultant cell gas mixture. These phenomena are typically referred to as foam aging.5.1.1 For some rigid gas-filled closed-cell foam insulation products produced using blowing agent gases that diffuse very rapidly out of the full-thickness foam product, such as expanded polystyrene, there is no need to accelerate the aging process.5.1.2 Physical gas diffusion phenomena occur in three dimensions. The one-dimensional form of the diffusion equations used in the development of this practice are valid only for planar geometries, that is, for specimens that have parallel faces and where the thickness is much smaller than the width and much smaller than the length.NOTE 3: Please see Appendix X3 for a discussion of the theory of accelerated aging via thin slicing.NOTE 4: Theoretical and experimental evaluations of the aging of insulation in radial forms, such as pipe insulation, have been made. (6) However, these practices have not evolved to the point of inclusion in the test standard.5.2 The change in thermal resistance due to the phenomena described in 5.1 usually occurs over an extended period of time. Information regarding changes in the thermal resistance of these materials as a function of time is required in a shorter period of time so that decisions regarding formulations, production, and comparisons with other materials can be made.5.3 Specifications C578, C591, C1029, C1126 and C1289 on rigid closed-cell foams measure thermal resistance after conditioning at 23 ± 1°C [73 ± 2°F] for 180 ± 5 days from the time of manufacture or at 60 ± 1°C [140 ± 2°F] for 90 days. This conditioning can be used for comparative purposes, but is not sufficient to describe long-term thermal resistance. This requirement demonstrates the importance of the aging phenomena within this class of products.5.4 The Prescriptive Method in Part A provides long-term thermal resistance values on a consistent basis for a variety of purposes, including product evaluation, specifications, or product comparisons. The consistent basis for these purposes is provided by a series of specific procedural constraints, which are not required in the Research Method described in Part B. The values produced by the Prescriptive Method correspond to the thermal resistance at an age of five years, which corresponds closely to the average thermal resistance over a 15-year service life (7, 8).5.4.1 It is recommended that any material standard that refers to C1303 to provide a product rating for long-term thermal resistance specify the Part A Test Method of C1303.5.5 The Research Method in Part B provides a relationship between thermal conductivity, age, and product thickness. The calculation methods given in Part B can be used to predict the resistance at any specific point in time as well as the average resistance over a specific time period.NOTE 5: The 5-year aged values produced in Part A can be derived from the Part B data only if all other Part A requirements are met.5.6 This test method addresses three separate elements relating to the aging of rigid closed-cell plastic foams.5.6.1 Specimen Preparation—Techniques for the preparation of thin flat specimens, including their extraction from the “as manufactured” product, and the measurement of specimen thickness are discussed.5.6.2 Measurement of the Thermal Resistance—Thermal resistance measurements, taken at scheduled times, are an integral part of the test method.5.6.3 Interpretation of Data—Procedures are included to properly apply the theory and techniques to achieve the desired goals.1.1 This test method covers a procedure for predicting the long-term thermal resistance (LTTR) of unfaced or permeably faced rigid gas-filled closed-cell foam insulations by reducing the specimen thickness to accelerate aging under controlled laboratory conditions (1-5) .2NOTE 1: See Terminology, 3.2.1, for the meaning of the word aging within this standard.1.2 Rigid gas-filled closed-cell foam insulation includes all cellular plastic insulations manufactured with the intent to retain a blowing agent other than air.1.3 This test method is limited to unfaced or permeably faced, homogeneous materials. This method is applied to a wide range of rigid closed-cell foam insulation types, including but not limited to: extruded polystyrene, polyurethane, polyisocyanurate, and phenolic. This test method does not apply to impermeably faced rigid closed-cell foams or to rigid closed-cell bun stock foams.NOTE 2: See Note 8 for more details regarding the applicability of this test method to rigid closed-cell bun stock foams.1.4 This test method utilizes referenced standard test procedures for measuring thermal resistance. Periodic measurements are performed on specimens to observe the effects of aging. Specimens of reduced thickness (that is, thin slices) are used to shorten the time required for these observations. The results of these measurements are used to predict the long-term thermal resistance of the material.1.5 The test method is given in two parts. The Prescriptive Method in Part A provides long-term thermal resistance values on a consistent basis that can be used for a variety of purposes, including product evaluation, specifications, or product comparisons. The Research Method in part B provides a general relationship between thermal conductivity, age, and product thickness.1.5.1 To use the Prescriptive Method, the date of manufacture must be known, which usually involves the cooperation of the manufacturer.1.6 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 Table of Contents:   Section 1Reference Documents 2Terminology 3Summary of Test Method 4 5Part A: The Prescriptive Method 6  Applicability 6.1    Qualification Requirements 6.1.1    Facing Permeability 6.1.2  Apparatus 6.2  Sampling 6.3    Schedule 6.3.1  Specimen Preparation 6.4    Goal 6.4.1    Schedule 6.4.2    Replicate Test Specimen Sets 6.4.3    Specimen Extraction 6.4.4    Slice Flatness 6.4.5    Slice Thickness 6.4.6    Stack Composition 6.4.7  Storage Conditioning 6.5  Test Procedure 6.6    Thermal Resistance Measurement Schedule 6.6.1    Thermal Resistance Measurements 6.6.2    Product Density 6.6.3  Calculations 6.7Part B: The Research Method 7  Background 7.1  TDSL Apparatus 7.2  Sampling Schedule 7.3  Specimen Preparation 7.4  Storage Conditioning 7.5  Test Procedure 7.6  Calculations 7.7Reporting 8 Reporting for Part A, the Prescriptive Method 8.1 Reporting for Part B, the Research Method 8.2Precision and Bias 9Keywords 10Mandatory Information – Qualification Annex A1 Specimen Preparation A1.1 Homogeneity Qualification A1.2Thermal Conductivity Equivalence Test Procedure A1.3 Alternate Product Thickness Qualification A1.4Example Calculations A1.5Mandatory Information-Preparation of Test Specimens for Spray-Foam Products Annex A2Effect Of TDSL Appendix X1History of the Standard Appendix X2Theory of Foam Aging Appendix X3References  1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This test method uses specific starting point conditions for the froth flotation response to accomplish the following:4.1.1 Assess responses of one or more coals or blends of coal, and4.1.2 Evaluate and determine froth flotation circuit performance.1.1 This test method covers a laboratory procedure for conducting a single froth flotation test on fine coal (that is, nominal top size of 600 μm (No. 30 U.S.A. Standard Sieve Series) or finer) using a defined set of starting point conditions for the operating variables.1.2 This test method does not completely cover specific procedures for the investigation of flotation kinetics. Such a test is specialized and highly dependent upon the objective of the data.1.3 Since optimum conditions for flotation are usually not found at the specified starting points, suggestions for development of grade/recovery curves are given in Appendix X1. Such a procedure is very case-specific and involves running a series of flotation tests in which some of the operating variables are changed in order to optimize conditions for either yield or grade.1.4 Laboratory flotation results need not be representative of the flotation response of coal in full-scale situations, but a consistent baseline can be established against which full-scale performance can be compared.1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.6 Material Safety Data Sheets (MSDS) for reagents used are to be obtained from suppliers who are to be consulted before work with any chemicals used in this test method.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice describes a cell adhesion method that can be used to provide a detachment percent at a given RCF for cells that have adhered to a substrate, typically for a short time. The information generated by this practice can be used to obtain a semi-quantitative measurement of the adhesion of cells to either an uncoated or pre-coated substrate, when compared to a reference (adherent) cell type on the same substrate. As described in Reyes and Garcia (2003), it is recommended that the 50 % point be used for either ligand concentration or RCF for the most robust measurement of adhesion strength. The adhesion may vary due to changes in the phenotype of the cells or as a result of the specific properties of the surface. The substrate may include tissue culture-treated polystyrene, biomaterials, or bioactive surfaces. If the substrate is a hydrogel, care must be taken to avoid cohesive failure in the hydrogel (that is, detached cells have pulled away fragments of gel). The coating may consist of (but is not limited to) the following: natural or synthetic biomaterials, hydrogels, components of extracellular matrix (ECM), ligands, adhesion or bioactive molecules, genes, or gene products. Cell concentration is also critical, as use of too high a concentration of cells may result in cells detaching as a sheet, rather than as individual cells. This centrifugation approach, once validated, may be applicable for quality control (QC) and product development. However, until the method is correlated to other measures of cell attachment, the current method should be run in parallel with other known measures of cell adhesion.4.2 This practice does not cover methods to quantitate changes in gene expression, or changes in biomarkers, as identified by immunostaining. This practice additionally does not cover quantitative image analysis techniques. In some cases, the change in adhesive properties may reflect on the degree of differentiation or de-differentiation of the cells. However, it is worth noting that adhesive interactions do not necessarily reflect the differentiation state of a particular cell type, although in many instances they do. (See X1.3 for application to the adhesion of chondrocytes.)1.1 This practice covers a centrifugation cell adhesion assay that can be used to detect changes in adhesive characteristics of cells with passage or treatments. This approach measures the force required to detach cells from a substrate. Adhesion, among many variables, may vary due to changes in the phenotype of the cells.1.2 This practice does not cover methods to verify the uniformity of coating of surfaces, nor does it cover methods for characterizing surfaces.1.3 The cells may include adult, progenitor, or stem cells from any species. The types of cells may include chondrocytes, fibroblasts, osteoblast, islet cells, or other relevant adherent cell types.1.4 This practice does not cover methods for isolating or harvesting of cells. This practice does not cover methods to quantitate changes in gene expression, or changes in biomarker type or concentration, as identified by immunostaining. Nor does this practice cover quantitative image analysis techniques.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Cell Therapy Products may be used to treat clinical conditions, for example in regenerative medicine (e.g. type I diabetes, acute myocardial infarction, pediatric congenital heart disease, chronic ischemic heart failure, cancer, Crohn’s disease, chronic wound repair, nerve and spinal cord injury, musculoskeletal repair), and may be used for immunotherapy (e.g. graft versus host disease, CAR-T therapy).5.2 Autologous, allogeneic, and xenogeneic cells may be used to make a product.5.3 A product may be cells only, cells combined with an inert carrier, cells within an extracellular matrix, or cells within a synthetic scaffold, and will include tissue engineered medical products containing cells.5.4 Cells may be gene-modified cells.5.5 Cells may be adult or embryonic stem cells.5.6 Cells may be minimally manipulated.1.1 This guide is intended as a resource for individuals and organizations involved in the development, production, delivery, and regulation of cellular therapy products (CTPs) including genetically modified cells, tissue engineered medical products (TEMPs) and combination products where cell activity is a functional component of the final product.1.2 This Guide was developed to include input derived from several previously published guidance documents and standards (section 2.4). It is the intent of this Guide is to reflect the current perspectives for CTP potency assays.1.3 CTPs can provide therapy by localized or systemic treatment of a disease or pathology.1.4 The products may provide a relatively short therapy, may be transient, or may be permanent and provide long-term therapy.1.5 The products may be cells alone, cells combined with a carrier that is transient, or cells combined with a scaffold or other components that function in the overall therapy.1.6 Potency assays may be in-vitro or in-vivo assays designed to determine the potency of a specific product. In-vivo assays are likely to be particularly useful to study the mechanism of action (MOA) of the therapy, but may not be desirable for final product quality control where they may be time-consuming and expensive, and where in-vitro assays may be preferable.1.7 It is likely that multiple assays, and possibly both in-vitro and in-vivo assays, will be required to provide a broad measure of potency. However, in-vitro assays are likely to be preferred as release assays for products, and so studies to identify potency assays should emphasize in-vitro assays that are correlative or predictive of preclinical or clinical results.1.8 Potency assays should be developed during the product development cycle and therefore are likely to be more comprehensive at the end of that cycle compared to the beginning of product development and testing. It is recommended that potency assays be developed as early as possible in the product development cycle (Figs. 1 and 2).FIG. 1 Progressive Implementation of Potency AssaysFIG. 2 Flow Chart for Stages in Product Development Showing When Potency Assays Will Be Developed and Introduced1.9 Potency measurements are used as part of the testing for cell and cell-based products to demonstrate that product lots meet defined specifications when released for clinical use.1.10 Shelf life specifications should be developed during the product development process to include potency measurements.1.11 This standard guide is not intended to apply to drug or gene therapy products. However, genetically modified cell therapies, for example the chimeric antigen receptor-T (CAR-T) cell therapy, which the United States FDA classifies as gene therapy, are applicable.1.12 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.13 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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