A high-speed gateable image pipeline

We present the performance of a high-speed gateable vacuum image pipeline, which permits individual images to be delayed and selected from continuous non-repetitive image stream. This device is composed of a vacuum tube equipped with a photocathode at one end, a phosphor screen at the other end, and a system of metal grids in between. Photoelectrons produced by the images focused on the photocathode, are guided by a uniform magnetic field, parallel to the tube axis. By changing the grid potentials, the drift time of the photoelectrons inside the tube can be varied from 0.35 to 1.5 μs. An image can then be selected by an external trigger with a time resolution in the range of 4–30 ns, depending on the delay time. The selected photoelectrons are finally accelerated onto the phosphor screen, set at 10 kV, where they reproduce the desired image. With a magnetic field of 0.1 T, a spatial resolution of 33 lp/mm was obtained. The high spatial and time resolution make this device an interesting tool for high-energy physics and astrophysics experiments, and for high-speed photography.     

An integrated approach to the optimum utilization of national tungsten resources: Technology gaps

A critical review of the current status of tungsten resources, of state-of-the-art processing technology and of product development in India vis-a-vis the world scenario is presented. An attempt has been made to identify technology gap areas requiring attention.     

The specific antibacterial proliferation of reactive arthritis synovial T cells is not due to their higher proportion of CD45RO+ cells compared to peripheral blood

OBJECTIVE: To determine the role of synovial fluid (SF) compared to peripheral blood (PB) CD45RO+ T cells in patients with reactive arthritis (ReA) and undifferentiated oligoarthritis. METHODS: We examined SF and PB of 8 patients with a specific lymphocyte proliferation to Yersinia enterocolitica (n = 5) and Chlamydia trachomatis (n = 3). After depletion of the CD45RA+ T cell subset by dynabeads, the remaining T cells (> 95% CD45RO+) from PB and SF of these patients were again stimulated with these bacterial antigens. RESULTS: The mean stimulation index (SI) of these 8 patients with ReA (n = 5) and undifferentiated oligoarthritis (n = 3) was 30.3 +/- 21.86 in SF compared to 1.36 +/- 0.75 in PB. The enrichment of CD45RO+ cells influenced the antigen specific proliferative response of T cells neither in PB (SI = 1.75 +/- 1.35) nor in SF (26.1 +/- 24.05); the initial difference remained unchanged. CONCLUSION: Our findings suggest that the antigen specific lymphocyte proliferation obtained with SF cells is not due to abundance of nonspecific CD45RO+ T cells but can rather be taken as an indication of specific recognition of local bacterial antigens in ReA.     

Sonographic detection of clinically unsuspected swallowed toothpicks and their gastrointestinal complications

We retrospectively analyzed the clinical presentation and imaging investigation in 4 cases of surgically (2 cases) or endoscopically (2 cases) proven toothpick-related gastrointestinal perforation. The toothpick perforated the stomach (2 cases), the sigmoid (1 case), and the ileum (1 case). Sonographic appearance of the toothpick was a linear, hyperechoic (3 cases) or hypoechoic (1 case) image of variable length (mean: 2.5 cm) with inconsistent posterior shadowing in the longitudinal axis. In transverse section a hyperechoic dot (4 cases) with clear, thin, sharp, posterior shadowing (3 cases) was seen. Following sonography (4 cases), CT scan (2 cases), and upper GI study (2 cases), the preoperative diagnosis of GI perforation by foreign body compatible with toothpick was made in all cases, although none of the patients was aware of having swallowed a toothpick. This information will be of help in making early sonographic diagnosis of toothpick-related GI perforation in patients with or without symptoms.     

Topical laryngo-tracheal anesthesia and intraocular pressure in anesthesia for ophthalmic surgery

OBJECTIVE: The reflex response to orotracheal intubation provokes an increase of arterial pressure accompanied by an increase of chorioides volume and a consequent ocular hypertone. There are several methods to reduce the reflex response due to intubation. One of the most effective is topical anaesthesia of larynx and trachea. Experiments were directed to evaluate the efficacy of topical anaesthesia to reduce the intraocular hypertone due to orotracheal intubation. DESIGN: A prospective randomized mask study was conduct on patients undergoing ophthalmologic (anterior segment) surgery at the Eye Clinic of Florence University. METHODS: Intraocular pressure was measured by a Goldman tonometer at four times: T0 = basal, T1 = 2' minutes after induction of general anaesthesia, T2 = 2' minutes after laryngoscopy, T3 = 2' minutes after orotracheal intubation. At the same moments, systolic blood pressure, heart rate, rate pressure pro duct were measured. Patients were randomly divided in two groups: Group L (n = 10) in which was evaluated the efficacy of laryngotracheal topical spray of lidocaine 4% (2 ml) and Group F (n = 10) in which saline was used instead of anesthetic. The filling of the LTA kit (Abbott) was made by a person not involved in the experiments. DATA ANALYSIS: Student's t test for unpaired data. RESULTS: Topical anaesthesia reduces the increase of intraocular pressure, hypertension and rate pressure product due to intubation. The intraocular pressure reduces to 13% less than basal value in Group L and increase to 50% more than basal value in Group F. CONCLUSION: The topical anaesthesia of larynx and trachea is effective to reduce the intraocular hypertension due to the reflex response evoked by orotracheal intubation.     

Major abdominal surgery and the clearance of lipid emulsions

Reaction of bacterial adhesins with complementary receptors on the surfaces of mucosal respiratory, gastrointestinal and genitourinary cells leads to bacterial adhesion to the human body. This is the first step in the sequence of events leading to infection. It has been observed that subinhibitory concentrations (sub-MICs) of some antibiotics are able to reduce bacterial adhesion. The pharmacokinetic curves of antibiotics show that these sub-MICs are present in tissues during a typical course of therapy. This study investigated the ability of sub-MICs of seven macrolides and four fluoroquinolones to reduce adhesiveness of Staphylococcus aureus to human buccal cells. The literature generally reports data for only one antibiotic at a time. To obtain an overall view of the findings of eleven antibiotics together, the data have been normalized according to the molecular weight of each antibiotic and the dose-effect curves determined.     

Calculation of electrodynamic properties of a biconical resonator

Translated from Izmeritel'naya Tekhnika, No. 3, pp. 57–58, March, 1993.     

Some scientist-practitioners do.

Comments on the argument of L. T. Hoshmand and D. E. Polkinghorn (see record 1992-21300-001) that psychological practice should inform science to the same degree that science informs practice. Based on a survey of 121 faculty members in programs accredited by the American Psychological Association, 65% reported practice activity. The authors agree that the problem involves a much more complex integrative task that goes beyond simply recognizing knowledge gained in practice settings as valid. (PsycINFO Database Record (c) 2010 APA, all rights reserved)