Extent and severity of periodontal destruction based on partial clinical assessments

OBJECTIVES: To evaluate the postoperative analgesic efficacy, side effects and acceptance by patients and nurses of intravenous "patient-controlled analgesia" (PCA) with morphine, metamizole and buprenorphine. MATERIAL AND METHODS: In this randomized double blind prospective study of 150 patients in three groups receiving morphine (group A), metamizole (group B) or buprenorphine (group C), the patients had undergone low abdominal surgery with the same anesthetic protocol. Pain was recorded during the first 48 h after surgery on an orally-communicated scale of none or slight = 0, moderate = 1 and severe = 2. Upon the first report of moderate pain, patients were administered an intravenous bolus containing 5 mg morphine, 1 g metamizole or 0.15 mg buprenorphine. A perfusion pump was then connected and set with one bolus of 1.2 mg morphine, one of 333 mg metamizole or one of 0.04 buprenorphine. The maximum dose allowed in 24 h was 40 mg morphine, 8 g metamizole or 1.2 mg buprenorphine. The minimum interval between doses was 30 min for all three groups. Side effects reported were respiratory depression, sedation, nausea, vomiting, pruritus, perspiration and pain upon administration. Patients and nurses were asked to evaluate the system when the pump was disconnected and the results were then analyzed statistically. RESULTS: The analgesic effect was satisfactory in all three groups, with no significant differences among them. The percentages of patients reaching the maximum allowed dose on the first day were 2% with morphine, 18% (p < 0.05) with metamizole and 8% with buprenorphine. No respiratory depression was observed. Sedation was greater with morphine and buprenorphine than with metamizole (p = 0.0001). Pruritus was also greater with morphine and buprenorphine than with metamizole (p = 0.02) and pain upon infusion was greater with metamizole (p = 0.0002). CONCLUSIONS: Intravenous postoperative PCA was effective with all three drugs studied. Patient and nurse acceptance was good and side effects were few in the three groups. The lower rate of side effects for metamizole makes it the drug of choice.     

Modern aspects of far-infrared gas lasers

Contents A short survey is presented on the recent development of optically pumped pulsed far-infrared (FIR) or THz gas lasers. This includes the new distributed-feedback (DFB) and helical-feedback (HFB) FIR gas lasers as well as the subnanosecond-single-pulse FIR gas lasers pumped by 50 ns 10 m pulses of hybrid CO₂ lasers truncated within ca. 10 ps at their maximum by a novel ultrafast laser-triggered plasma shutter. These lasers show interesting phenomena such as standard and swept-gain superradiance as well as anticorrelated oscillations of the far-infrared emission and the 10 m pump radiation in the Raman regime. In this context it was discovered that FIR laser gases, e.g., CH₃F, NH₃, D₂O, CH₃CN, can be used successfully as spectral filters in Optical-Free-Induction-Decay 10 m CO₂ laser systems instead of the standard hot CO₂ gas. Finally, the single ultrashort FIR pulses are presently applied to FIR or THz quantumwell detectors and to high-T _c superconductors to gain further information on their exciting and complicated features.

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Aktuelle Aspekte der Ferninfrarot (THz) Gaslaser

Übersicht Aktuelle Probleme und Resultate der Forschung über optisch-gepumpte gepulste Ferninfrarot (FIR)- resp. THz-Gaslaser werden erläutert. Diese betreffen sowohl die neuartigen Distributed Feedback (DFB) und Helical Feedback (HFB) FIR Gaslaser, als auch FIR Gaslaser, die gepumpt werden mit den 50 ns 10 m Pulsen von Hybriden CO₂ Lasern, welche mit neu entwickelten, Lasergesteuerten Plasmaschaltern innerhalb ca. 10 ps im Maximum abgeschnitten werden. Damit erzielt man Subnanosekunden-FIR Einzelpulse. Diese Laser zeigen interessante Phänomene, wie normale und verstärkte Superstrahlung oder antikorrelierte Fluktuationen der FIR Strahlung und 10 m Pumpstrahlung im Raman-Emissionsstadium. In diesem Zusammenhang wurde festgestellt, daß FIR Laser-Gase, z. B. CH₃F, NH₃, D₂O, CH₃CN, erfolgreich als Spektralfilter in Optical-Free-Induction-Decay 10 m CO₂ Lasersystemen das übliche heiße CO₂ Gas ersetzen können. Die einzelnen ultrakurzen FIR-Pulse werden zur Zeit zum Test neuer FIR resp. THz Quantum-Well-Detektoren und zur Untersuchung ihrer Einwirkung auf Hoch-T _c -Supraleiter verwendet.

     

The influence of cooling rate during alloy casting on the oxidation behaviour of TiAl-based intermetallics

The oxidation behaviour of the intermetallic phase Ti-50 at% Al at 900 °C was studied. It was found that the oxidation behaviour strongly depends on the composition and distribution of the and ₂-phases in the alloy microstructure. As this microstructure strongly depends on the alloy cooling rate, the oxidation behaviour of TiAl-based intermetallics is significantly affected by the casting procedure and subsequent heat treatment. Rapid cooling from high temperature (T 1400 °C) has a beneficial effect on oxidation behaviour.On leave from the Academy of Mining and Metallurgy, Krakow, Poland.     

A study on the yield stress of perlite-filled high-density polyethylenes

Four different types of high-density polyethylenes were blended with expanded perlite at different compositions. -aminopropyltriethoxysilane was applied to perlite (2 wt%) from ether and water solutions to enhance the interfacial adhesion between the polymer and the filler. It was shown that silane treatment advances the yield stress with improving dispersion and increasing the interfacial adhesion of the filler with the polymer matrix. The experimental results were then checked with the expression of Turcsanyiet al.'s.     

Assessing two new wearable input paradigms: The Finger-Joint-Gesture palm-keypad glove and the invisible phone clock

Text and digit entry speed of two wearable one-handed input paradigms, the Finger-Joint-Gesture palm-keypad glove and the Invisible Phone Clock, were benchmarked against traditional one-handed cellular phone keypad input in a repeated-measurement design employing 18 subjects using a 9-word sentence. No significant difference in error-corrected text entry speed (5.3 ec-wpm) was found. Digit entry speed was significantly faster (8.3 ec-wpm) and differed significantly between input paradigms. Furthermore, digit entry was fastest for the traditional cellular phone keypad and slowest for the Invisible Clock keypad. A prediction model based on Fitts' law slightly overestimated text entry speed for novice users. Another prediction model, where each movement time between successive keys was corrected for key repeat time for each specific input paradigm, predicted the experimental results more accurately. Thirteen of the subjects ranked the Invisible Phone Clock as 1^st choice. The subjects' mapping of the Ericsson cellular phone functions (YES, CLR, NO, <,> and Address Book) was not according to the designer's model, partly due to functional fixedness. The input paradigms could be suitable candidates for new fragmentised interfaces where wearability is the key issue.     

The metabolism of fenazox in tomato plants

Results from investigations on the metabolism of 14C-Fenazox show that in 6-8 weeks old tomato-plants (sort "Harzfeuer") the agent undergoes a biotransformation. After chromatographic separation the structure of the biotransformation products was elucidated by comparison to authentic test substances, by derivatization as well as by means of physico-chemical methods. With that, the following metabolites were identified: non-transformed Fenazox, o-hydroxyazobenzene, o-hydroxyaniline, and p-hydroxyaniline. Probably, the agent is first transformed enzymatically or non-enzymatically into o-hydroxyazobenzene, then follows a reductive cleavage into o-hydroxyaniline and aniline. In its turn, the latter is transformed into o-hydroxy- and p-hydroxyaniline. Experiments in the field of transformation kinetics indicated that the concentration of the applied Fenazox rapidly decreases and that the first transformation product o-hydroxyazobenzene in the beginning increases and then again decreases in its concentration. With increasing application time it comes to an increase of the non-extractable residues.     

Some remarks on the application of a two-surface model in plasticity

Summary An internal variable theory of rate-independent plasticity is presented incorporating a combination of classical models of kinematic hardening as well as isotropic hardening. In addition to the yield surface a second bounding surface has been introduced to accommodate to problems with non-radial loading paths. The behaviour of this model unter uniaxial and complex loading has been tested and compared with experimental results and other theoretical predictions.With 10 Figures