A review of the FDA draft guidance document for software validation: guidance for industry.

A Draft Guidance Document (Version 1.1) was issued by the United States Food and Drug Administration (FDA) to address the software validation requirement of the Quality System Regulation, 21 CFR Part 820, effective June 1, 1997. The guidance document outlines validation considerations that the FDA regards as applicable to both medical device software and software used to "design, develop or manufacture" medical devices. The Draft Guidance is available at the FDA web site http:@www.fda.gov/cdrh/comps/swareval++ +.html. Presented here is a review of the main features of the FDA document for Quality System Regulation (QSR), and some guidance for its implementation in industry.     

Good clinical laboratory practice (GCLP): the need for a hybrid of good laboratory practice and good clinical practice guidelines/standards for medical testing laboratories conducting clinical trials in developing countries.

There has been a significant increase in the number of clinical drug trials (particularly phase III) being conducted in developing countries for infectious diseases such as HIV, malaria, and tuberculosis. Laboratory results provided by medical testing laboratories in the region are critical to ensuring the safety of patients and the generation of good quality data. A number of well accepted Good Clinical Practice (GCP) and Good Laboratory Practice (GLP) guidelines govern the conduct of clinical trials internationally. Good Clinical Practice guidelines remain too vague with respect to sample analysis to ensure practical implementation in these laboratories. In their strictest sense, Good Laboratory Practice guidelines refer to the analysis of samples from non-clinical studies. A specific set of minimum standards or requirements for practical implementation of clinical trial requirements in medical testing laboratories in the developing world is urgently required.     

A review of US EPA and FDA requirements for electronic records, electronic signatures, and electronic submissions.

Both the United States Environmental Protection Agency (EPA) and the U.S. Food and Drug Administration (FDA) have issued regulatory documents that address the issues and requirements concerning electronic reporting to the Agencies. EPA has published two comprehensive and useful electronic data interchange (EDI) guidelines: 1) the EPA Electronic Data Interchange (EDI) Implementation Guideline, Draft of September 23, 1994 and October 18, 1994 that is available at the following EPA web site address: www.epa.gov/oppeedi1/guidelines/general.pdf and 2) the Interim Final Notice, Filing of Electronic Reports via Electronic Data Interchange, September 4, 1996, Federal Register Notice [FRL-5601-4, Volume 61, Number 172, page 46684], also available at: www.epa.gov/oppeedi1/edipoli.htm. The FDA has published a guidance document titled, "Guidance for Industry, Computerized Systems Used in Clinical Trials, April 1999" that is available at FDA's web site: www.fda.gov/ora/compliance_ref/bimo/ffinalcct.++ +htm. FDA's guidance document addresses a number of issues for electronic records that are applicable to all areas of GLP compliance. Another FDA document presently under development is titled, "Electronic Standards for the Transmission of Regulatory Information (ESTRI) Gateway." The ESTRI document defines strategic plans for electronic submissions to FDA. FDA has published a guidance document in this area titled, "Guidance for Industry: Providing Regulatory Submissions in Electronic Format--General Considerations, January 1999." This guidance document is available at: www.fda.gov/cder/guidance/index.htm. FDA has also published an important final rule applicable to all electronic records and signatures that is part of the U.S. Title 21 Code of Federal Regulations (CFR), Part 11, titled, "FDA's Final Rule, Electronic Records; Electronic Signatures, effective August 20, 1997." This FDA ruling is discussed below and is available at: www.fda.gov/cder/esig/index.htm.     

我国良好实验室规范实施现状及发展

良好实验室规范（GLP）是一种规范的管理性文件。我国GLP的实施起步较晚,与发达国家相比还存在一定的差距。近年来,我国相关部门加大了管理力度,进一步完善了GLP体系。加强GLP实验室的管理,推行GLP检查和认证,有望推进国际安全性资料的互认,减少重复实验和资源浪费,降低研究成本。     

A comparison of the U.S. EPA FIFRA GLP standards with the U.S. FDA GLP standards for nonclinical laboratory studies.

In the early 1980's both the Environmental Protection Agency and the Food and Drug Administration were receiving studies on the products that they regulate that were unscientifically sound, some even being fraudulent. Studies were being submitted that had not been done under sound scientific practice; data were missing; necessary documentation to reconstruct the study, also known as an audit trail, was not in place, it was this evidence that lead to the Good Laboratory Practice Standards (GLPs) being codified and becoming regulation. The GLPs were meant to assure that studies submitted to the agencies for the registration of products for which they were responsible would protect the environment, and, the safety and health of the public.     

Principles and practice of grc. A review

The theory of fibre reinforcement is reviewed and requirements for effective reinforcement identified. These requirements are then related to the stress/strain and ageing behaviour of typical sprayed grc to identify relevant and important factors. Finally an attempt has been made to explain certain design, production and control practices in the light of reinforcement theory and material properties.     

Current practice and open issues in strengthening historical buildings with composites

Modern techniques and innovative materials are often quite rapidly proposed and allowed in current practice, even for restoration of historical constructions, in which essential preservation criteria must be taken into account. The considerable variability and complexity of masonry structures and types means that choosing the most appropriate structural models and interventions is particularly difficult, since they must be based on suitable knowledge of both existing and new materials, and on their interactions in environmental and loading conditions. This paper discusses the potentials and limitations of externally bonded composite materials in masonry structures and components, in the light of knowledge acquired from research in the field, together with the requirements and recommendations of codes and restoration documents. The analysis of some case studies is presented, to highlight the advantages and constraints in the use of composites for strengthening historical buildings.     

FDA Regulation of Implantable Sensors: Demonstrating Safety and Effectiveness for Marketing in the U.S.

Implantable sensors are gaining considerable attention in the research and medical communities due to their potential to enhance the detection and monitoring of medical conditions such as cancer, diabetes, and heart disease. The use of implantable sensors for these exciting applications bring them under the regulatory oversight of the United States Food and Drug Administration (FDA). As medical devices intended for long-term implantation that inherently involve some risk, the FDA will carefully evaluate these products prior to allowing them to enter the U.S. market. This paper provides a brief overview of the FDA medical device regulatory framework under which implantable sensors for medical purposes are regulated. It also addresses particular concerns the FDA may raise with respect to these products including, potential sensor breakage and migration in vivo, biocompatibility, electromagnetic compatibility, electromagnetic interference, wireless telemetry, risk/benefit, and clinical utility.     

Using corrosion meters of polarization resistance in laboratory and industrial practice

Translated from Fiziko-Khimicheskaya Mekhanika Materialov, No. 5, pp. 95–97, September–October, 1988.     

Theoretical and experimental validation of a simple method to reproduce representative DEF-prone conditions in laboratory

Delayed Ettringite Formation (DEF) is a possible autogenous expansive reaction of concrete. It can affect materials that have experienced temperatures higher than about 65 °C at early age. This temperature increase can be the result of the cement heat of hydration in massive structures where the heat transfers are particularly low. To understand the effects of DEF, it is necessary to be able to reproduce thermal DEF-prone conditions in laboratory. This paper proposes a method developed during an extensive experimental programme that aimed at studying the mechanical effects of DEF on structures built with different concretes. The objective was to design a single heat treatment profile to generate homogeneous and similar temperature fields in specimens of various geometries, concrete constituents and mix proportions. It has been demonstrated that quasi-adiabatic conditions were to be realized at early age, whatever the samples size, to simulate the curing conditions in massive structures. The experimental method developed is described in details: the design of the temperature profile, the experimental device and its operation are presented. Both a numeric and an experimental validation are proposed. They emphasize the good accuracy of the process and demonstrate the possibility to trigger similar DEF potential expansions due to the thermal history for all the specimens of the programme.     

Forward calculation for interferometers: method and validation

An approach to approximating the instrument response for an unapodized interferometer is presented. The approach comprises functions that are local enough in frequency space (no more than five wave numbers) that one can use the Planck function at a single frequency to calculate the radiance at a given frequency and atmospheric pressure level, and it is well behaved (transmittances change monotonically from 1.0 to 0.0), so existing transmittance calculation procedures can be used. It is faster than calculating radiances at a high resolution, doing a Fourier transform, and then doing a second transform, and it produces brightness temperatures that agree with exact values to better than the 0.01 K that is due to errors in the approximation. The approach is accurate enough and fast enough to be used for calculating unapodized radiances from an interferometer. It also can be used to calculate transmittances as well as radiances.     

BCGA Code of practice for liquid oxygen storage at user premises: a review

The British Compressed Gases Association (BCGA) has identified the need for a comprehensive Code of Practice giving recommendations for the safe storage and handling of liquid oxygen (LOX) at user's premises. The Code of Practice is presently in the course of preparation and identifies the factors which should be taken into account in the design of the installation and in the testing, commissioning, operation and maintenance of the system. Particular reference is made to the hazards of oxygen and the precautions required and to the safety/separation distances which are recommended. The Health and Safety Executive has had a significant input into the draft Code of Practice. This Paper discusses the main points covered by the Code.     

Multiwalled carbon nanotubes in alfalfa and wheat: toxicology and uptake

Data on the bioavailability and toxicity of carbon nanotubes (CNTs) in the environment, and, in particular, on their interactions with vascular plants, are limited. We investigated the effects of industrial-grade multiwalled CNTs (75 wt% CNTs) and their impurities on alfalfa and wheat. Phytotoxicity assays were performed during both seed germination and seedling growth. The germinations of both species were tolerant of up to 2560 mg l⁻¹ CNTs, and root elongation was enhanced in alfalfa and wheat seedlings exposed to CNTs. Remarkably, catalyst impurities also enhanced root elongation in alfalfa seedlings as well as wheat germination. Thus the impurities, not solely the CNTs, impacted the plants. CNT internalization by plants was investigated using electron microscopy and two-dimensional Raman mapping. The latter showed that CNTs were adsorbed onto the root surfaces of alfalfa and wheat without significant uptake or translocation. Electron microscopy investigations of internalization were inconclusive owing to poor contrast, so Fe₃O₄-functionalized CNTs were prepared and studied using energy-filter mapping of Fe₃O₄. CNTs bearing Fe₃O₄ nanoparticles were detected in the epidermis of one wheat root tip only, suggesting that internalization was possible but unusual. Thus, alfalfa and wheat tolerated high concentrations of industrial-grade multiwalled CNTs, which adsorbed onto their roots but were rarely taken up.     

Biomimetics: its practice and theory.

Biomimetics, a name coined by Otto Schmitt in the 1950s for the transfer of ideas and analogues from biology to technology, has produced some significant and successful devices and concepts in the past 50 years, but is still empirical. We show that TRIZ, the Russian system of problem solving, can be adapted to illuminate and manipulate this process of transfer. Analysis using TRIZ shows that there is only 12% similarity between biology and technology in the principles which solutions to problems illustrate, and while technology solves problems largely by manipulating usage of energy, biology uses information and structure, two factors largely ignored by technology.     

Multispectral method for skin imaging: development and validation

A visible wide field multispectral system for comprehensive imaging of skin chromophores and blood vessels has been implemented, and an inhomogeneous Monte Carlo model of photon migration with randomly distributed blood vessels embedded in dermis has been developed. Predetermined nonlinear transforms have been obtained to address the nonlinear interdependent relationship among diffusive reflectance spectra, skin physiology properties, and geometry. For validation, in addition to real skin experiments and phantoms experiments, two alternative methods for blood vessel imaging have been used on the same set of subjects to compensate for the lack of ground truth for skin subsurface imaging.     

Annual recertification program for audit standards used in the EPA PM2.5 Performance Evaluation Program.

This paper describes procedures used to perform 152 annual recertifications of temperature, pressure, and flow rate audit standards. It discusses the metrology laboratories and the uncertainty of their recertifications. It describes the data base for the standards that tracks their recertifications and shipments. Finally, it presents some illustrative recertification results and describes what these results reveal about the audit standards and the recertifications.     

Power in top management teams: dimensions, measurement, and validation.

Top managers' power plays a key role in strategic decision making. However, although numerous scholars have recognized its importance, very few have attempted to measure the phenomenon. In this article, I present a set of dimensions measuring top managers' power and suggest a measurement methodology to facilitate empirical inquiry. Data from a group of 1,763 top managers in three industries were used to assess the validity and reliability of the power dimensions in three studies. Results demonstrate strong support for the proposed power dimensions.