Mobilization of hepatic cadmium in pregnant rats

Mobilization of hepatic cadmium (Cd) in pregnant rats was investigated. Female Sprague-Dawley rats (200-250 g) were injected subcutaneously, daily with 1.0 mg Cd/kg body weight as CdCl2 for 8 days. A group of these rats was made pregnant. Copper (Cu), zinc (Zn), Cd, and metallothionein (MT) concentrations in the liver, kidney, and plasma of the control and Cd-injected, pregnant and nonpregnant rats, were compared. The hepatic Cd concentration of the Cd-injected rats decreased by 40% during pregnancy and became significantly lower than that of the nonpregnant Cd-injected rats. On the other hand, there was a concomitant increase (60%) of Cd concentrations in the kidney of the Cd-injected pregnant rats. MT in the Cd-injected rats also showed a similar pattern of decrease in hepatic concentrations and increase in renal concentrations during pregnancy. Both Cd and MT contents in the placenta of the Cd-injected rats were higher than those of the control and there was a significant increase over the gestational period. Plasma Cd and MT concentrations of the Cd-injected pregnant rats were higher than those of Cd-injected nonpregnant rats. These results suggest that pregnancy can mobilize the hepatic Cd which can be transferred to the kidney and placenta through the blood plasma. Moreover, the blood urea nitrogen levels of the pregnant Cd-injected rats were increased on Gestation Day 21 and 7 days after delivery, indicating signs of Cd nephropathy. The hepatic Cd, Cu, Zn, and MT concentrations of the newborn rats, however, were unaltered by Cd injections. Therefore, it is possible that pregnancy may induce a high risk of Cd nephrotoxicity in women with chronic Cd exposure.     

Clearance of mercury (HG-197, HG-203) vapor inhaled by human subjects

Five human subjects inhaled a mixture of stable and radioactive mercury vapor for periods of 14 to 24 minutes. The subjects retained an average of 74% of that inhaled. Evidence is submitted to show that the retention occurred almost entirely in the alveoli. For 3 days after exposure, the exhaled breath was passed at intervals through activated charcoal traps for sampling periods of 10 to 35 minutes. The data indicated that an average of 7% of the retained mercury was lost in the expired breath, with a half time of 18 hours. Examination of the subjects in a whole body counter yielded average half times for mercury clearance from different parts of the body as follows: lung, 1.7 days; head, 21 days; kidney region, 64 days; chest, 43 days; and whole body, 58 days.     

Quality enhancement in fresh and frozen lingcod (Ophiodon elongates) fillets by employment of fish oil incorporated chitosan coatings

The 3% chitosan solutions incorporating 10% fish oil (w/w chitosan, containing 91.2% EPA and DHA) with or without the addition of 0.8% vitamin E were prepared. Fresh lingcod (Ophiodon elongates) fillets were vacuum-impregnated in coating solution at 100 mm Hg for 10 min followed by atmospheric restoration for 15 min, dried, and then stored at 2 °C or −20 °C for 3-weeks and 3-months, respectively, for physicochemical and microbial quality evaluation. Chitosan–fish oil coating increased total lipid and omega-3 fatty acid contents of fish by about 3-fold, reduced TBARS values in both fresh and frozen samples, and also decreased drip loss of frozen samples by 14.1–27.6%. Chitosan coatings resulted in 0.37–1.19 and 0.27–1.55 log CFU/g reductions in total plate and psychrotrophic counts in cold stored and frozen stored samples, respectively. Chitosan–fish oil coatings may be used to extend shelf-life and fortify omega-3 fatty acid in lean fish.     

Effects of adhesive type and polystyrene concentration on the shear strength of bonded polystyrene/high-density polyethylene blends

The lap-shear strengths of adhesively bonded polystyrene (PS), high-density polyethylene (HDPE), and their blends, were studied as a function of adhesive type and blend composition. The performance of virgin and recycled polymer systems was examined. The lap-shear strength depended strongly on the amount of PS in the blend and the type of adhesive, and the acrylic adhesives demonstrated the best performance for all compositions. Bonded strengths of HDPE increased by approximately 50% when HDPE was blended with 34% PS, the co-continuous composition. The results indicate that structural elements made from PS/HDPE immiscible blends may be effectively bonded with adhesives without expensive surface treatments.     

INTELLIGENT BEHAVIOR IN MACHINES EMERGING FROM A COLLECTION OF INTERACTIVE CONTROL STRUCTURES

Control strategies that decompose the competence of an agent into independent, task-achieving control structures are emerging as viable alternatives to the notion that a robot is an explicit symbol processing device with input and output extensions in the form of sensors and actuators. This approach draws inspiration from ethology and the cognitive sciences, where the competence of biological creatures is seen to be a result of the successful combination of several distinct behavior patterns that enable them to interact effectively with their environments. The distinction between classical approaches that view intelligent behavior as the outcome of symbolic manipulations and an alternate approach that asserts that it is the careful integration of distributed, goal-competent control structures that lead to intelligent behavior is analyzed in detail. It is found that this dichotomy can be said to arise from the paradigm that is chosen to represent the knowledge at the disposal of the agent. Structurally encoded knowledge requiring an active interpreter for the knowledge to be exhibited in action leads to the symbol processing paradigm for intelligent behavior, whereas the interactive model for knowledge representation assumes that the knowledge at the disposal of an active agent resides within goal-competent, interactive control structures. A formalism is developed for representing the goal-directed nature of these interactive control structures with clear control-module boundaries. An implementation is then presented to demonstrate some of the basic features of this methodology.     

Local wound infiltration with bupivacaine in lumbar laminectomy

BACKGROUND: Parenteral administration of narcotics has been the mainstay for postoperative pain relief in patients undergoing lumbar laminectomy. However, this may lead to respiratory depression and nausea, which may be hazardous in these patients. METHODS: We evaluated the efficacy of wound infiltration with bupivacaine in 45 consecutive patients undergoing elective single-level lumbar laminectomy for intervertebral disc prolapse in a prospective, double-blind, randomized controlled trial. Prior to wound closure, the muscle and subcutaneous tissues were infiltrated with bupivacaine 0.375% or sterile physiologic saline. Postoperatively, the patients were assessed hourly for pain and an analgesic administered if the patient had moderate or severe pain. RESULTS: All the 21 placebo recipients required analgesics in the first 9 hours postoperatively, compared to only 11 of 24 patients who received bupivacaine (p < 0.001). The mean (standard deviation) time before administration of the first dose of analgesic postoperatively in the bupivacaine and placebo recipients was 807.7 (567.6) minutes and 181.4 (110.1) minutes, respectively (p < 0.001). No adverse effects of local wound infiltration were noted. CONCLUSIONS: Local wound infiltration with bupivacaine is a safe and effective method for providing postoperative pain relief and reducing narcotic use in patients undergoing lumbar laminectomy.     

Higher Quality Requirements: Supporting Joint Application Development with the Nominal Group Technique

Miscommunication among systems developers and users has plagued systems requirements determination under conventional approaches and has contributed to several systems failures. Joint Application Development (JAD) was introduced to alleviate this problem by bringing together developers, users, and managers in face-to-face workshops designed to produce higher quality requirements. However, JAD sessions are conducted under the freely interacting group structure, which makes them susceptible to many of the classical problems commonly encountered during group deliberations. In this paper we present a case for integrating JAD and the nominal group technique (NGT), a group protocol that was designed to solve problems similar to those encountered in JAD. We tested our proposition in a laboratory experiment consisting of 24 group sessions, in which professional JAD facilitators led a diverse group of business professionals, managers, and advanced business students in specifying high-level requirements (under JAD and with the integrated techniques) for a simulated IS problem. The neutral and objective measures of their effects on the quality of the resulting requirements indicate that the combination of these group process structures seems to neutralize the negative impacts of group dynamics often experienced in JAD sessions, and contributes to improvements in the quality of the requirements.