Retention data

Analytical information taken from a chromatogram has almost exclusively involved either retention data (retention times, capacity factors, etc.) for peak identification or peak heights and peak areas for quantitative assessment. The width of the peak has been rarely used for analytical purposes, except occasionally to obtain approximate values for peak areas. Nevertheless, as seen from the Rate Theory, the peak width is inversely proportional to the solute diffusivity which, in turn, is a function of the solute molecular weight. It follows that for high molecular weight materials, particularly those that cannot be volatalized in the ionization source of a mass spectrometer, peak width measurement offers an approximate source of molecular weight data for very intractable solutes. 

Data Lockout Data Retention Data Archiving Data Sharing... 

Data collected at each participating site must be stored in a read-only format at that site for future reference. The Institutional Review Board (IRB) at each participating site requires that the site retain its local database after trial closeout. Data retention can be achieved in various ways. However the method should ensure that (1) participating sites are not be able to modify retained data (2) data are presented in a way that allows sites to easily locate any data form for any subject at any trial visit and (3) the site PI is solely responsible for the retained data. 

Abdellatif et al. reported a method for data retention [56] in which collected electronic data forms of each participating site are saved on a read-only CD as PDF files after the site s database has been locked. SAS Output Delivery System (ODS), PROC Template, and PROC Forms were used to construct a read-only CD of the data forms in a PDF format for each site and then sent to the site s PI. 

Abdellatif M, Thakkar B, Motyka D. Constructing data retention CDs for the VA CSP 399 participating sites after trial completion. Hines VA Research Day 2003 P39. 

Conduct of a nonclinical laboratory study Reporting of nonclinical laboratory study results Storage and retrieval of records and data Retention of records Purpose... 

Data Preservation To preserve a complete and accurate set of records by copying electronic data to a removable or remote storage medium and to manage the data retention. The data integrity must not be compromised during the preservation process ... 

Starting in about 1978, the Research Directors Committee of the Association began to address the subject. The membership of the committee was polled regarding their views on data retention. This was largely stimulated by proposed EPA guidelines on this matter. I won t attempt to suitmarize the results of that survey, but emerging from it was a consensus definition on the term "raw data," and a consensus statement on retention of saitples. The definition of "raw data" which the industry preferred was as follows ... 

The words "contribute significantly" and "for purposes of registration were key, and represented an important change in the definition vis-a-vis what was proposed by EPA. It was felt that the inclusion of these words would be a more reasonable definition because it reduced the scope of raw data retention to the very type which was needed for validation and which could be reasonably expected to be retained. 

Retention Data. Retention indices for pesticides in System GA, and relative retention times for pesticides in System GK, are given in Table 1... 

Process step definition Functional performance criteria Functional failure mode analysis Failure mode recovery requirements Informational requirements Information structures Legacy system interfaces Data entry range Data retention requirements Human/machine interface requirements Screen specifications Data entry modes Refresh rates Data migration... 

System failure during read/write operations Data retention following system failure Cyclical file management Prevention of duplicate record creation Referential integrity Impact on existing modules Regression testing... 

Data Historians should be vahdated. Data must be protected from unauthorized and unintentional modification. This might be achieved through locking down data (i.e., no subsequent write permissions given after data created). The requirement for any audit trails needs to be specified. Data retention requirements need to be defined in accordance with company policy and regulatory requirements. Software used to retrieve data should be validated. Any dependencies on storage media need to be understood and managed. Backup and restore are key processes. System interfaces should also be specified and tested. 

The t/-ans-(S, S)-dach complex, [Pt(trans-(S,S)-dach)(ascorbato-C, 0 )], can be prepared by using the method described in Section B. This complex is more soluble in water than the trans-(B, B)-dach complex, and it is necessary to concentrate the solution of the S,S-dach complex to induce crystallization. Yields of up to 45% are typical for this isomer. HPLC data retention time =1.8min (under the conditions reported previously). 

Food and Drug Administration investigators found generally acceptable performance in the archival and record retention areas as well as in the area of the physical facilities associated with animal care and laboratory operations. The lack of findings in these areas is encouraging, as it may be recalled that a major problem that precipitated FDA s concern for the quality and integrity of safety data was in the area of raw data retention. 

An analogous situation can be seen in the requirements for data retention and storage, where the DHHS Guideline stipulates Similarly, research data, including the primary experimental results, should be retained for a sufficient period of time to allow analysis and repetition by others of published findings. .. Retention time may vary under different circumstances. In some fields, five or seven years are specified as the minimum period of retention. A minimum of five years is required. Again, the GLP Principles are more precise in their requirements than just to mention data, including the primary experimental results . They firmly require that not only aU... 

Operating data Retention time Supersaturation Suspension density Volumetric production rate Solution upward velocity... 

The combination of a chromatographic column with the IMS enables multidimensional data analysis, and allows peak identification by the use of chromatographic data (retention times) and also by use of the specific ion mobility data (arrival time at the Faraday plate) of the ions formed... 

Many investigators place value on retentivity data. Retentivity cannot be defined exactly but it refers to the phenomenon that when a char has taken up a vapor to capacity from a relatively strong concentration, a certain proportion of this adsorbed vapor can be removed with ease in a current of air while the remainder is retained more firmly. Data retentivity, as given by different investigators, are comparable only if obtained under corresponding conditions of time, temperature, and velocity of air stream.20,21 Chaney13 describes an accelerated routine procedure. In this,... 

Type of estimated retention data. Retention times are required when the objective is to help in developing a GCxGC method, and resolution or retention patterns must be estimated for different conditions. A promising possibility consists in predicting, instead of specific retention data, parameters that allow their calculation for different columns and conditions. At the time of writing, only a simplified approach based on a solvation parameter model [32] has been presented [33]. 

Where exact peak position matching is not made, then retention indices are an excellent alternative for porting retention data. Retention indices are extremely... 

Append the rebuttal to the driver s information in the carrier s appropriate file, to be included as part of the response for any subsequent investigating prospective employers for the duration of the 3 year data retention requirement. 

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