Nondestructive testing of welds on thin-walled tubing

Special ultrasonic search unit, or transducer assembly, reliably inspects the quality of melt-through welds of fusion welded tubing couplers for hydraulic lines. This instrumentation can also be used to detect faulty braze bonds in thin-walled, small diameter joints and wall thickness of thin-walled metal tubing

Morphological heterogeneity of HeLa cell mitochondria visualized by a modified diaminobenzidine staining technique

The diaminobenzidine (DAB) technique for the ultrastructural localization of sites of cytochrome c oxidase activity in animal tissues has been adapted to the visualization of mitochondria in animal cells growing in culture. The modified technique allows the staining of mitochondria in all cells in coverslip preparatins for light microscopy. Electron microscopy of thin sections of material treated by this method has revealed that all mitochondrial profiles within a cell (and only these) are stained and they exhibit a well preserved size and internal structure. Coverslip cultures of synchronized and unsynchronized HeLa (F-315) cells stained with the DAB reaction were examined under oil immersion. In the majority of the cells, mitochondria were recognized as discrete bodies in the thinner peripheral portion of the cytoplasm. This observation indicates that in a large proportion of HeLa F-315 cells, at least under the growth conditions used here, the mitochondrial complement is dividied into distinct organelles. This examination also revealed a considerable morphological heterogeneity of mitochondria, which exhibited an ovoid or short rod-like or, less frequently, long filamentous shape, with some evidence of branching. The variability in mitochondrial morphology appeared to be far more prounced between different cells than within individual cells; this cellular heterogeneity was not related in any obvious way to cell-cycle-dependent changes

The cell cycle program of polypeptide labeling in Chlamydomonas reinhardtii

The cell cycle program of polypeptide labeling in syndhronous cultures of wild-type Chlamydomonas reinhardtii was analyzed by pulse-labeling cells with 35SO4 = or [3H]arginine at different cell cycle stages. Nearly 100 labeled membrane and soluble polypeptides were resolved and studied using one-dimensional sodium dodecyl sulfate (SDS)- polyacrylamide gel electrophoresis. The labeling experiments produced the following results. (a) Total 35SO4 = and [3H]arginine incorporation rates varied independently throughout the cell cycle. 35SO4 = incorporation was highest in the mid-light phase, while [3H]arginine incorporation peaked in the dark phase just before cell division. (b) The relative labeling rate for 20 of 100 polypeptides showed significant fluctuations (3-12 fold) during the cell cycle. The remaining polypeptides were labeled at a rate commensurate with total 35SO4 = or [3H]arginine incorporation. The polypeptides that showed significant fluctuations in relative labeling rates served as markers to identify cell cycle stages. (c) The effects of illumination conditions on the apparent cell cycle stage-specific labeling of polypeptides were tested. Shifting light-grown asynchronous cells to the dark had an immediate and pronounced effect on the pattern of polypeptide labeling, but shifting dark-phase syndhronous cells to the light had little effect. The apparent cell cycle variations in the labeling of ribulose 1,5-biphosphate (RUBP)-carboxylase were strongly influenced by illumination effects. (d) Pulse-chase experiments with light-grown asynchronous cells revealed little turnover or inter- conversion of labeled polypeptides within one cell generation, meaning that major polypeptides, whether labeled in a stage-specific manner or not, do not appear transiently in the cell cycle of actively dividing, light-grown cells. The cell cycle program of labeling was used to analyze effects of a temperature-sensitive cycle blocked (cb) mutant. A synchronous culture of ts10001 was shifted to restrictive temperature before its block point to prevent it from dividing. The mutant continued its cell cycle program of polypeptide labeling for over a cell generation, despite its inability to divide

Near Real Time Ultrasonic Pulse Echo Holographic Imaging System

Nondestructive flaw characterization has keen research interests throughout industry. The nuclear industry is no exception. Identifying the size, shape, orientation, type and position of material flaws in nuclear reactor pressure vessels has a top priority. Under a contract with the Electric Power Research Institute of Palo Alto, California, Battelle-Northwest is developing a demonstration model of a sequentially pulsed phased linear array system for ultrasonic inspection of reactor vessels. This program employs the linear array in both pulse echo and holographic modes and provides near real time images of the weld zone volume. The objectives of the program are to develop a rapid and accurate means for sizing subsurface defects in heavy section steel members. This article outlines the first six months effort on the two year program

Mitochondrial growth and division during the cell cycle in HeLa cells

The growth and division of mitochondria during the cell cycle was investigated by a morphometric analysis of electron micrographs of synchronized HeLa cells. The ratio of total outer membrane contour length to cytoplasmic area did not vary significantly during the cell cycle, implying a continuous growth of the mitochondrial outer membrane. The mean fraction of cytoplasmic area occupied by mitochondrial profiles was likewise found to remain constant, indicating that the increase in total mitochondrial volume per cell occurs continuously during interphase, in such a way that the mitochondrial complement occupies a constant fraction( approximately 10-11(percent)) of the volume of the cytoplasm. The mean area, outer membrane contour length, and axis ratio of the mitochondrial profiles also did not vary appreciably during the cell cycle; furthermore, the close similarity of the frequency distributions of these parameters for the six experimental time-points suggested a stable mitochondrial shape distribution. The constancy of both the mean mitochondrial profile area and the number of mitochondrial profiles per unit of cytoplasmic area was interpreted to indicate the continuous division of mitochondria at the level of the cell population. Furthermore, no evidence was found for the occurrence of synchronous mitochondrial growth and division within individual cells. Thus, it appears that, in HeLa cells, there is no fixed temporal relationship between the growth and division of mitochondria and the events of the cell cycle. A number of statistical methods were developed for the purpose of making numerical estimates of certain three-dimensional cellular and mitochondrial parameters. Mean cellular and cytoplasmic volumes were calculated for the six time-points; both exhibited a nonlinear, approx. twofold increase. A comparison of the axis ratio distributions of the mitochondrial profiles with theoretical distributions expected from random sectioning of bodies of various three-dimensional shapes allowed the derivation of an "average" mitochondrial shape. This, in turn, permitted calculations to be made which expressed the two-dimensional results in three-dimensional terms. Thus, the estimated values for the number of mitochondria per unit of cytoplasmic volume and for the mean mitochondrial volume were found to remain constant during the cell cycle, while the estimated number of mitochondria per cell increase approx. twofold in an essentially continuous manner

Development of Advanced NDE Ultrasonic Equipment

Recent studies to determine the probability of detection of nondestructive examination methods by the Air Force indicate that these capabilities are severely limited. One of the factors contributing to the insufficiency of ultrasonic testing is related to a general lack of versatility and capability of commercial ultrasonic equipment. Inadequate instrument reliability, inconsistent components including transducers, and uncertain calibration standards further compromise the potential utility of this method. Battelle Pacific Northwest Laboratories, under the sponsorship of the manufacturing Technology Division of the Air Force Materials Laboratory, is developing an advanced ultrasonic nondestructive testing system directed at resolving these defficiencies. As a result, this program will establish a modular ultrasonic system specification that will prevent near term obsolescence by permitting the addition of new technology such as ARPA developments in the form of additional or replacement modules. This paper will describe the Phase I and II tasks and objectives which are planned to establish an equipment specification, demonstrate initial prototype systems, and provide a procurement specification and technical manuals. Progress to date will be summarized

Overview of Planned Ultrasonic Imaging System with Automatic ALN Data Interpretation

This presentation discusses a new program designed to investigate the effectiveness with which adaptive learning network (ALNJ analysis can be combined with linear array, phase steered, ultrasonic imaging techniques to provide an enhanced means for automatic data interpretations. The DARPA-sponsored program is being performed as a team effort between Adaptronics, Inc. and Battelle-Northwest. Battelle, under a subcontract from Adaptronics, is adapting the linear array imaging system being developed for the Electric Power Research Institute of Palo Alto, California, for use on this project. A special ultrasonic array will be developed to operate with the high-speed imaging system to acquire and record both specular and nonspecular signal information in both the time and frequency domains. Signal information from a multitude of simple and complex reflectors and defects wilI be recorded on the PDP 11 disk pack incorporated into the ultrasonic imaging system. Adaptronics will utilize the time·domain and frequency spectral data recorded from several thousand data points to develop algorithms and train networks which may describe uniquely the pattern of the reflections. The objective of the program is to provide a high-speed and automatic means for detecting, locating, sizing and displaying flaws in solid materials