Design of nonaxisymmetrical image intensifiers

The concept of a nonaxisymmetrical X-ray image intensifier is presented in this paper. Instead of cylindrical electrodes, as in the conventional device, this intensifier is equipped with planar electrodes. Each one consists of some number of elementary quadrilateral patches, which are mutually insulated from each other and supplied with the proper voltages. The algorithm for determining potentials which must be supplied to the elementary electrodes is described in the paper. The algorithm has been validated by comparing the electric field distributions in both configurations. Details of the electric field distribution are also helpful in evaluating the optical characteristics of the intensifier     

Healon GV versus Healon in demanding cataract surgery

Spontaneous nasal tumors are rare in mice, and only one adenocarcinoma and two more primary neoplasms of the nose have been observed in our files of long-term feeding studies, which are composed of 3,419 male and 3,521 female CD-1 (Crl:CD-1 (ICR)BR) mice. This adenocarcinoma was a 1-cm-diameter mass observed grossly in the right nasal cavity of a 454-day-old, male CD-1 mouse from a treated group in a bioassay study conducted with 340 males and 340 females. The neoplastic epithelial cells affected the normal nasal architecture on the right side of the nose. Roughly, tumor neoplastic cells of the outer, lateral portion occurred as cuboidal to low columnar cells with basilarily located nuclei and eosinophilic cytoplasm. These cells were arranged in cylindrical profiles and frequently entrapped acini of the glands of the maxillary sinus. Neoplastic epithelial cells of the inner, medial portion appeared as serous acinar or ductular structures circumscribed by multiple lagers of myoepithelial-like cells. Staining failed to demonstrate mucous secretion. The site of origin of this neoplasm appeared to be the serous glands of the maxillary sinus. The adenocarcinoma was believed to be spontaneous.     

Study of 18-cm long single-sided AC-coupled silicon microstripdetectors

The SSC GEM silicon Central Tracker design incorporated 18-cm long single-sided AC-coupled silicon microstrip ladders. Compared to the 12-cm long ladders considered in the preliminary stages of the tracker design, the 18-cm long ladders have the advantage of reduced cost, channel count and overall power consumption, and led to a simplified tracker assembly. However, such long ships also present the challenge of maintaining satisfactory performance. The increased capacitance and series resistance contribute to lower signal-to-noise ratios, longer time walk, higher power consumption per channel and increased probability of crosstalk to neighboring channels. In this paper, an accurate method to calculate the geometric capacitance of the AC-coupled microstrips is presented and the calculated results are compared with measurements, SPICE simulations are performed to predict the noise, the extent of interstrip capacitive coupling and the dispersion of the detector signal due to the finite series resistance of the metal strips and the long length of the detector. The influence of the preamplifier current and the shaping time on the signal and noise levels is also presented. The study concludes that the 18-cm long ladders can successfully satisfy the performance goals of the GEM silicon Central Tracker     

Forensic implications of the difficulties of defining delusions

Delusions are evasive to define: (1) Within the process of defining, one uses part of the final conclusion, which should derive from the basic definition (in other words, Circular reasoning); (2) Many, if not most, of so-called normal persons, hold delusion-like ideas; (3) Delusion becomes, usually, more understandable and less bizarre when investigated; (4) Delusions are not unique by remaining resistible to reason; (5) For every delusional content, as bizarre and remote as it may be, there is at least one cultural niche, in which the same content is considered legitimate and reasonable, (if no important and dignified). The forensic implications of these difficulties (to define delusions), will be discussed and elaborated.     

Reactions and early-age properties inin-situ polymerized gypsum-acryl amide composites

The development of the reactions and early-age properties of a system consisting of calcium sulfate hemihydrate and acrylamide monomer was studied. The hydration of the hemi-hydrate and the polymerization of the acrylamide were determined at various time intervals, and the expansion and rise in temperature were continuously recorded. Setting times and flow were determined using standard test methods. It was shown that acrylamide and hemi-hydrate could react simultaneously to form gypsum and polyacrylamide composite in which the reactions to form both components advanced almost until completion, for mixes containing up to 10% acrylamide. Increase in the content of acrylamide improved the flow properties of the mix, but delayed the setting. At contents of 2% acrylamide, the hemi-hydrate reaction occurred prior to the polymerization process. Above 6% acrylamide, the polymerization reaction preceded the hemi-hydrate reaction. This sequence of reactions can account for the observations that above 6% acrylamide two peaks in the heat liberation curves could be detected as well as that expansion was smaller at the higher acrylamide content, due probably to separation between gypsum crystals forming when the polymer is already present.     

Evidence for distinct signaling mechanisms in two mammalian olfactory sense organs

In mammals, olfactory stimuli are detected by sensory neurons at two distinct sites: the olfactory epithelium (OE) of the nasal cavity and the neuroepithelium of the vomeronasal organ (VNO). While the OE can detect volatile chemicals released from numerous sources, the VNO appears to be specialized to detect pheromones that are emitted by other animals and that convey information of behavioral or physiological importance. The mechanisms underlying sensory transduction in the OE have been well studied and a number of components of the transduction cascade have been cloned. Here, we investigated sensory transduction in the VNO by asking whether VNO neurons express molecules that have been implicated in sensory transduction in the OE. Using in situ hybridization and Northern blot analyses, we found that most of the olfactory transduction components examined, including the guanine nucleotide binding protein alpha subunit (G-alpha-olf), adenylyl cyclase type III, and an olfactory cyclic nucleotide-gated (CNG) channel subunit (oCNC1), are not expressed by VNO sensory neurons. In contrast, VNO neurons do express a second olfactory CNG channel subunit (oCNC2). These results indicate that VNO sensory transduction is distinct from that in the OE but raise the possibility that, like OE sensory transduction, sensory transduction in the VNO might involve cyclic nucleotide-gated ion channels.     

Inhibition of G1 cyclin expression in normal rat kidney cells by inostamycin, a phosphatidylinositol synthesis inhibitor

We previously reported that inostamycin, an inhibitor of CDP-DG: inositol transferase, inhibited cell proliferation in normal rat kidney (NRK) cells by blocking cell cycle progression at the G1 phase. In the present paper, we report the effect of inostamycin on the serum-induced activation of Ser/Thr protein kinases that are involved in G1 progression. In quiescent NRK cells mitogen-activated protein kinase (MAP kinase) and casein kinase II were activated within 15 min after serum addition. Neither activation was affected by the treatment with inostamycin. However, in the inostamycin-treated cell, cyclin-dependent kinase 2 (CDK2) failed to be activated after serum stimulation. Since serum-induced expression of cyclin E was also suppressed by inostamycin, this inhibitor would appear to block CDK2 activation by inhibiting cyclin E expression. Furthermore, inostamycin also inhibited cyclin D1 expression induced by serum; and consequently, hyperphosphorylation of retinoblastoma protein (pRB) by RB-kinases such as CDK4 and CDK2 was abolished, which would result in elimination of functional inactivation of pRB. Thus, early G1 arrest in NRK cells by inostamycin is due to the inhibition of cyclin D1 and E expressions.