A Two-Channel Picture Coding System: I--Real-Time Implementation

The two-channel system previously reported has been implemented in hardware using system parameters appropriate to consumer television. The basic system divides the spectrum into lowand high-frequency spatial components. The lows are coarsely sampled and finely quantized and the highs finely sampled and coarsely quantized using a companded, randomized quantizer. The purpose of this experiment was to demonstrate the potential of the system for low-cost practical application, to study the effect of the character of the randomizing noise, and to ascertain that there were no deleterious effects due to interlace, motion, or input noise. Theoretical noise calculations were qualitatively confirmed.     

Advanced IC packaging for the future applications

The performance of electronic equipment is improving rapidly. Portable electronic equipment requires smaller and thinner packaging systems for saving space and miniaturization. In addition, highly integrated, high-speed applications demand improved electrical performance to minimize noise effects. As a result of these considerations, the role of IC packaging has expanded from its traditional role of protecting the integrity and performance of an IC, to being a central factor in the development of electronic system concepts. In developing the optimum system, packaging technology must be a prime design consideration to ensure optimum performance, reliability, and cost. Soldering technology and Printed Wiring Board (PWB) routing density are two of the major technological issues facing miniaturized packaging systems today. Chip Scale Package (CSP), which is a new concept in packaging technology has been introduced. This is an ideal technology to enable the design and manufacture of the next generation of electronic equipment, while overcoming many of the technological issues facing system development     

Basic fibroblast growth factor as one of the essential factors regulating lens transdifferentiation of pigmented epithelial cells

In vitro transdifferentiation of retinal pigmented epithelial cells of the chick embryo into lens cells can be markedly enhanced by culture in the presence of testicular hyaluronidase and phenylthiourea. Since the commercial preparations of hyaluronidase that had previously been used were very crude, a search for the actual effective molecule(s) enhancing lens transdifferentiation was conducted. First, we purified the enzyme and tested the effect of the purified hyaluronidase. Highly purified hyaluronidase itself did not enhance lens transdifferentiation. The crude hyaluronidase was then separated according to affinity with heparin, considering the possibility that the fibroblast growth factor (FGF) is contained in the crude hyaluronidase. Transdifferentiation-enhancing activity was detected in the fraction which was bound to heparin and eluted with 2 M NaCl, where no hyaluronate-degrading activity existed. Analysis of the fraction by SDS-PAGE revealed the existence of an 18 kDa protein whose NH2-terminal sequence was identical to that of basic FGF. The basic FGF derived from bovine brain also enhanced lens transdifferentiation of pigmented epithelial cells. These findings suggest that basic FGF must play a major role in enhancing transdifferentiation of pigmented epithelial cells to lens cells.     

Increase in adhesion molecules on CD4+ cells and CD4+ cell subsets in synovial fluid from patients with rheumatoid arthritis

OBJECTIVE: To elucidate the role of adhesion molecules in the pathogenesis of rheumatoid arthritis (RA). METHODS: We evaluated their expression and that of an activation marker on CD4+ cell populations and CD4+ cell subsets in specimens of peripheral blood (PB) and synovial fluid (SF) obtained from 10 patients with RA and 7 with osteoarthritis (OA). A 2 or 3-color immunofluorescent method was used for analysis. RESULTS: The SF from both groups of patients showed a greater density of adhesion molecules including LFA-1 alpha, LFA-1 beta, CD2, VLA-4 alpha and VLA-5 alpha on CD4+ cells, and a higher percentage of CD4+HLA-DR+ cells compared with their PB. IN PB-CD4+ cell subsets from the arthritic and healthy subjects, the CD4+CD45RO+ cell population showed an increased expression of adhesion molecules compared with CD4+CD45RA+ cell population. The expression of adhesion molecules on circulating CD4+ cell population and CD4+ cell subsets from the patients with RA and OA was comparable to that from healthy subjects. SF from both groups of patients showed a higher percentage of CD4+CD45RO+ cells and a lower percentage of CD4+CD45RA+ cells. In SF-CD4+ cell subsets from patients with RA, the CD4+CD45RO+ cell population had an increased expression of VLA-4 alpha compared to the CD4+CD45RA+ cell population; however, there was no significant difference in other adhesion molecule expression and the percentage of HLA-DR+ cells between the 2 cell subsets. Furthermore, the expression of VLA-4 alpha on the CD4+CD45RO+ cell population in SF from patients with RA was significantly higher than that in matched PB. In CD4+CD45RA+ cell population from both groups of patients, SF showed an enhanced expression of adhesion molecules and an increased percentage of HLA-DR+ cells compared with matched PB. CONCLUSION: Our results suggest that increased expression of adhesion molecules and increased percentage of HLA-DR+ cells on CD4+ cells in SF may be responsible for cellular interactions between these cells and synovial cells or extracellular matrix.     

Amino acid sequences of hemoglobin beta chains of five species of pinnipeds: Neophoca cinerea, Otaria byronia, Eumetopias jubatus, Pusa hispida, and Pagophilus groenlandica

Pinnipeds (Otariidae, Odobenidae, and Phocidae) in the order Carnivora have one or two types (Hb I and Hb II) of hemoglobin components. These hemoglobins consist of identical beta chains and different alpha chains. We determined the complete amino acid sequences of the hemoglobin beta chain of three species of Otariidae (Australian sea lion, South American sea lion, and northern sea lion) and two species of Phocidae (ringed seal and harp seal) from intact beta chain and chemical cleavage fragments. The sequences are similar to beta chains of the already known sequences of pinnipeds. These sequences were compared with those of other carnivores (Mustelidae, Ursidae, Canidae, and Felidae) and adult human hemoglobin beta chain. Using Artiodactyla (pig) as an outgroup, we find that the tree constructed by means of phylogenetic analysis shows that Odobenidae is closest to Otariidae, and that Otariidae and Odobenidae are closer to Mustelidae than to Phocidae.     

Comparison of routine and selective endoscopic retrograde cholangiography before laparoscopic cholecystectomy

To evaluate the role of endoscopic retrograde cholangiography (ERC) before laparoscopic cholecystectomy, we compared the frequency of concomitant common bile duct stones, their clinical outcome, and the frequency of bile duct injury between a group of 128 patients with routine preoperative ERC (group A) and 1010 patients with selective ERC (group B). Overall, 48 patients (4.2%) had duct stones, but the predictive signs were absent in six of them (12.5%). The stones were demonstrated by ERC and removed by sphincterotomy in all 11 patients in group A. Of 37 patients in group B, 22 were diagnosed by selective ERC and underwent endoscopic removal. Of four patients whose stones were found by operative cholangiography, one had immediate open surgery, another passed a stone spontaneously, and the other two underwent postoperative sphincterotomy, which failed in one. The stones were not recognized until pain recurred in the remaining 11 patients. Sphincterotomy was successful in nine patients but failed in the other two. Thus postoperative sphincterotomy failed in 3 of 13 patients (23%), necessitating open surgery. Forty-two patients overall (3.7%) had aberrant biliary tract anatomy, which did not lead to bile duct injury in any of the patients. Morbidity of routine ERC (3.1%) was lower than that of selective ERC (7.4%) (p < 0.05). It should be noted that a certain proportion of duct stones may be missed by selective ERC, necessitating laparotomy when sphincterotomy fails. The routine use of preoperative ERC may be justified at institutions where the expertise is available, at least until laparoscopic lithotomy becomes easy.     

Performance of Micro-fabricated Magnetic Calorimeters Arrays for X-Ray Spectroscopy

We have been developing array technology for fabricating magnetic calorimeters for X-ray astronomy. The magnetization change in each pixel of the paramagnetic sensor material due to the heat input of an absorbed X-ray is sensed by a meander shaped coil. With this geometry it is possible to obtain excellent energy sensitivity, low magnetic cross-talk and large format arrays fabricated on wafers that are separate from the SQUID read-out. A magnetic bias field for each pixel is generated by the use of a persistent current that is stored. We report on the results from our prototype arrays, which are coupled to low noise DC-SQUIDs. The first test results are presented and the sensitivity is compared with calculations.