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Notes: Model-independent chaos control techniques are inherently well-suited for the control of physiological systems for which quantitative system models are unavailable. The proportional perturbation feedback (PPF) control paradigm, which uses electrical stimulation to perturb directly the controlled system variable (e.g., the interbeat or interspike interval), was developed for excitable physiological systems that do not have an easily accessible system parameter. We develop the stable manifold placement (SMP) technique, a PPF-type technique which is simpler and more robust than the original PPF control algorithm. We use the SMP technique to control a simple geometric model of a chaotic system in the neighborhood of an unstable periodic orbit (UPO). We show that while the SMP technique can control a chaotic system that has UPO dynamics which are characterized by one stable manifold and one unstable manifold, the success of the SMP technique is sensitive to UPO parameter estimation errors. © 1997 American Institute of Physics.

Notes: Antiplatelet therapy may offer an advantage over warfarin in reducing adverse clinical events after intracoronary stem implantation. The mechanism of this effect has not been elucidated but platelet adhesion may play a predominant role in the process of subacute stent thrombosis. This study compared the effect on platelet, neutrophil, and thrombus deposition of three different anticoagulation regimens (aspirin/warfarin vs aspirin/ticlopidine vs aspirin alone) after intracoronary stenting in juvenile swine. Thirty stents were deployed in 15 juvenile farm swine randomized to one of 3 anticoagulation protocols: aspirin 325 mg/day; aspirin 325 mg/day and ticlopidine 500 mg/day; aspirin 325 mg/day and warfarin 0.1 mg/kg/day. Autologous platelets were labeled using 111Indium-oxime and a slotted tube metal stent was deployed using a high pressure balloon. Platelet deposition in the stented segment was determined at 24 hours. Each segment was analyzed by light microscopy to document an injury score; mean and maximum thrombus deposition per strut were measured; and neutrophils were counted on each metal strut and in the vessel wall. Platelet deposition at 24 hours was significantly higher in the aspirin/warfarin group (3.69 ± 1.16 ± 108 plts/cm2) than in the aspirin/ticlopidine (1.74 ± 0.45 ± 108 plts/cm2, P = 0.0009) or aspirin (2.42 ± 2.13 ± 108 plts/cm2, P = 0.03) groups. There was no significant difference between the aspirin and aspirin/ticlopidine groups (P = 0.9). Mean thrombus area per strut was significantly greater in the aspirin/warfarin group (0.027 ± 0.006 mm2) compared to the aspirin/ticlopidine group (0.017 ± 0.002 mm2, P = 0.002). The majority of the thrombus (79%) but minority of neutrophils (24%) were found on the stent struts. In this coronary stent model, warfarin given with aspirin was associated with greater thrombogenicity and more platelet deposition than either aspirin/ticlopidine or aspirin alone.

Notes: The purpose of this review is to discuss the use of new adjunctive pharmacological agents to improve the outcome of patients with obstructive coronary disease treated with stents. The goal of any form of adjunctive therapy is to improve procedural, in-hospital, and long-term outcome. In terms of stenting, this goal may be accomplished by developing strategies to prevent procedural and postprocedural thrombosis and to prevent postprocedural intimai hyperplasia. Recent studies suggest that more potent anticoagulant agents, particularly the new antiplatelet agents, may have an important role in this regard. High risk subsets in whom benefits may be more striking, including both clinical risk factors (acute MI, unstable angina, vein graft disease, and diabetes) and procedural risk factors (visible thrombus, uncovered persistent dissections, overlapping stents, suboptimal deployment, poor distal run-off, and “bail-out” use). Current “standard” anticoagulant therapy for stent placement would include aspirin, heparin, ticlopidine, and possibly (though much less popular now than previously) coumadin. More recent newer adjuncts include low molecular weight heparin, platelet IIb/IIIa antagonists (such as ReoPro), and thrombolylic agents. A number of other potential agents may find their way into clinked usage in the not-too-distant future. Adjunctive therapy can be considered not only for use “prophylactically”, prior to the procedure in high risk cases, but intraprocedurally for clinical situations or complications that may arise. There is increasing experience and an increasing comfort level with ReoPro usage in stent cases. Platelet GP IIb/IIIa-targeted therapy appears to be a useful adjunct to high risk stent procedures, Intraprocedural versus prophylactic administration of IIb/IIIa-targeted therapy in this setting continues to be highly controversial. Its utility in low risk settings is unknown, but will be clarified by ongoing clinical trials. A large number of additional exciting new pharmacological agents will be entering clinical trials in the very near future.〈section xml:id="abs1-1"〉〈title type="main"〉SummaryObviously, we are working at the fringes of our knowledge as we “push the envelope” of stenting and as we begin to incorporate new forms of adjunctive therapy. In the absence of hard data from randomized controlled trials, we make clinical decisions on the best information we have available at the time. What do we know at present?1. Platelet GP IIb/IIIa-targeted therapy does appear to be a useful adjunct for certain high risk stent procedures.2. Intraprocedural versus prophylactic administration of IIb/IIIa-targeted therapy as an adjunct to stent procedures continues to be highly controversial.3. The utility of IIb/IIIa-targeted therapy for low-risk stent procedures is unknown at present, but will be clarified by ongoing clinical trials.4. A large number of exciting new pharmacological agents, including oral and IV thrombin inhibitors, oral and IV IIb/IIIa blockers, tissue factor pathway inhibitor, adhesion molecule blockers, and other new anti-platelet agents will be undergoing clinical trials with stents in the very near future.With this information in hand, we can hopefully apply adjunctive therapy (regardless of the specific agent used) in a rational, efficacious, and cost-effective manner. We have learned a lot in recent years, especially about how much more we need to learn. Empiricism and controlled clinical trials only go so far on their own. By judiciously and critically evaluating the information in hand, we can continue to advance the safety and efficacy of intracoronary stents.

Notes: . Sequences of the small subunit rRNA genes of Amblyospora californica and an Amblyospora sp. from Culex salinarius were determined. These sequences were compared phylogenetically with 16 other microsporidia. The results suggest Amblyospora forms a sister taxon to the rest of the microsporidia examined. The basal position of Amblyospora is discussed with respect to the evolution of microsporidian life cycles. These sequences represent the longest microsporidian small subunit rRNA genes sequenced to date, 1,359 and 1,358 bp, respectively. Structural features and GC content (49% for both) are comparable to those of other microsporidia which have been sequenced.

Notes: Abstract: This study used the rat hippocampal slice preparation and the monocarboxylate transporter inhibitor, α-cyano-4-hydroxycinnamate (4-CIN), to assess the obligatory role that lactate plays in fueling the recovery of synaptic function after hypoxia upon reoxygenation. At a concentration of 500 µM, 4-CIN blocked lactate-supported synaptic function in hippocampal slices under normoxic conditions in 15 min. The inhibitor had no effect on glucose-supported synaptic function. Of control hippocampal slices exposed to 10-min hypoxia, 77.8 ± 6.8% recovered synaptic function after 30-min reoxygenation. Of slices supplemented with 500 µM 4-CIN, only 15 ± 10.9% recovered synaptic function despite the large amount of lactate formed during the hypoxic period and the abundance of glucose present before, during, and after hypoxia. These results indicate that 4-CIN, when present during hypoxia and reoxygenation, blocks lactate transport from astrocytes, where the bulk of anaerobic lactate is formed, to neurons, where lactate is being utilized aerobically to support recovery of function after hypoxia. These results unequivocally validate that brain lactate is an obligatory aerobic energy substrate for posthypoxia recovery of function.

Notes: A method of providing asymmetric feedback in the triangular ring laser structure was devised through the simple alterations of the waveguide shape. Two kinds of alterations were designed and implemented, one being the "optical diode," the other being the tapered waveguide. Unidirectional operation was achieved for the ring lasers, with a single-beam slope efficiency of 0.23 W/A, which was the highest single-beam slope efficiency reported for semiconductor ring lasers. © 1997 American Institute of Physics.

Notes: Recent studies of police response to violence in which men attack women with whom they have a history of shared intimacy have not addressed the issue that inspired research in the first place: the “leniency thesis” that police treat men who beat their spouses less punitively than other violent offenders. In addition, research examining the deterrent effects of various police treatments of misdemeanor domestic violence is not responsive to complaints that abused women are denied protection of law when they have been victims of serious, felony-grade, abuse by their spouses. This research analyzes the response of the Chester, Pennsylvania, police to 392 consecutively reported felony-grade assaults by persons whose identities were known to victims and police. Results confirm the leniency thesis. Tabular analysis demonstrates that arrests occurred in 13% of male-on-female spousal assaults and 28% of other assaults. Logit analysis indicates that this difference in police response is not attributable to other variables that might be expected to result in differential treatment. We conclude that the practices and results reported by research conducted in progressive police jurisdictions that volunteer to participate in studies of police response to violence against women may not be generalizable to the great majority of U.S. police agencies that have not welcomed such study.

Notes: Examines differences in discount store selection factors among both male and female members of the "baby busters" generation. Results indicate that significant differences in discount store selection factors do exist between male and female members of the baby busters generation. These findings suggest that the current practice of dual-gender positioning by discount stores may be less effective than the more traditional female-oriented approach.

Notes: In order to capitalize on the various technical and behavioural skills needed for a project, system development activities frequently are performed by teams. By surveying 239 information systems (IS) professionals, reports how IS managers, project leaders, and system analysts evaluate the importance of six criteria for determining the effectiveness of an IS team project. Results show that there is a significant difference among the IS professionals. IS managers give more weight to the amount of work a team produced, adherence to schedule, and adherence to budget than do project leaders and system analysts. Results indicate that all IS professionals report that they regard the quality of work produced by the team as the most critical criterion.

Notes: [Auszug] Kaposi's sarcoma-associated herpesvirus (KSHV) is a newly discovered herpesvirus etiologically associated with Kaposi's sarcoma (KS) and two lymphoproliferative disorders. We describe a KSHV vbcl-2 gene with homology to the proto-oncogene bcl-2. It is expressed in KS lesions and in cell lines ...