Abstract WP436: Sensory Distraction to Help Decrease Agitation in Stroke Patients

Background: Dysphagia is a common complication after stroke. To ensure adequate nutritional intake, nasogastric (NG) or other feeding tubes may be inserted. Post-stroke agitation and aggression can occur in 15 to 35% of stroke survivors as early as 4 days after stroke. At Rush University Medical Center (RUMC), it is common for the Stroke Unit patients to have feeding tubes and any other tubes necessary for treatment. It is a growing concern that agitated stroke patients self-remove feeding and other tubes requiring reinsertion and/or limb restraints. Although historically sensory modulation has not been heavily utilized in stroke patients, sensory based treatment objects in psychiatric inpatient units have been reported to reduce the use of restraints. Purpose: The purpose of this quality improvement project was to decrease agitation in stroke patients using sensory distraction objects (SDO). The goal of this project was to decrease the use of limb restraints and prevent patient self-removal and staff reinsertions of feeding and other tubes during this study period. Method: This project targeted stroke patients in the RUMC 12 West Tower Unit who were agitated, restless, impulsive, or anxious. Each patient was given a SDO, such as a plastic ring toy, glitter ball, activity belt, or a silk handkerchief attached to their gown. A decision tree was used to assign a SDO based on the patient’s cognitive and motor function. The Agitation Behavior Scale (ABS) was used to measure agitation in stroke patients; the scale was used pre- and post-implementation. Post-implementation assessment was done within one hour after the SDO is given. The use of limb restraints and patient self-removal of feeding and other tubes was observed. Conclusion: The project included 15 participants. Eleven out of 15 patients showed a decrease in agitation with a distraction object using the ABS. Only 20% of participants pulled out their feeding or other tube and two patients required restraints during the study period. In conclusion, this project did showcase a decrease in agitation for stroke patients using a SDO and decreased the use of limb restraints. The SDO prevented patient self-removal and staff reinsertion of feeding and other tubes.

Performance of constructed wetlands with different substrates for the treated effluent from municipal sewage plants

Constructed wetlands (CWs) are effective as an advanced treatment process for the treated effluent of municipal wastewater plants. An appropriate substrate, suitable macrophytes, and proper operation are crucial for pollutant abatement. In this research, three subsurface flow CWs with various substrates were investigated. Pollutants abatement efficiency under various operational schemes were analyzed. The results showed that the satisfactory hydraulic loading rate was 0.25 m3/(m2·d). When the C/N ratio of influent was adjusted to 5.87 by adding a carbon source, the denitrification and dephosphorization efficiency would be improved, with 7–8 mg/L for total nitrogen (TN) and 0.4 mg/L for total phosphorus (TP) in the effluent, which can achieve the Class 1A Discharge Standard for discharge to natural waterways in China. A greater depth of submersion for the substrate layer resulted in a more conducive environment for the abatement of nitrogen substances. However, a 40-cm depth of submersion in CWs results in better removal efficiency of TN and TP. A plastic ring substrate (PRS) contains biological enzyme promoter formula, which was conducive to nitrifying and denitrifying bacteria. The biofilm affinity and coordination with plants made the PRS more effective than the other two substrates, especially for NO3–-N and TN abatement efficiency.

Crushing of an Elastic-Plastic Ring Between Rigid Plates With and Without Unloading

Load-deflection curves are computed for an elastic-plastic ring that is slowly crushed between frictionless, rigid plates (platens). The ring is assumed to be inextensional with plane sections remaining plane and to obey a bi-linear stress-strain law with isotropic hardening. These assumptions lead to a local nonlinear moment-curvature relation identical to that developed by Liu et al. When inserted into the exact equation for moment equilibrium, this constitutive relation yields a second-order, nonlinear ordinary differential equation for the angle α between the deformed centerline of the ring and the horizontal. The numerical solution of this equation, which uses a combined penalty-continuation method, along with an auxiliary equation relating the vertical deflection to α, leads to overall load-deflection curves that depend on two dimensionless parameters, λ and μ. The first is the ratio of the plastic modulus to the elastic modulus; the second measures the ratio of plastic to elastic effects. As μ→0, the overall load-deflection curve of Frish-Fay for the elastica is recovered; as μ→∞, that of DeRuntz and Hodge for a rigid-perfectly plastic ring is recovered. Three scenarios are considered: I0, in which an initially straight, stress-free beam is bent elastically into a ring and then crushed; II0, in which an initially stress-free ring is crushed; and III0, in which an initially straight beam is bent first elastically and then elastically-plastically into a ring and then crushed. Results for scenario II0 are shown to agree well with experiments of Reddy and Reid if λ=0.01 and μ=10 and 20 and with experiments of Avalle and Goglio if λ=0.02 and μ=11. In scenarios I0 and II0, the effects of unloading prove to be small, reinforcing a similar conclusion of Liu et al., who considered the large-deflection of an elastic-plastic cantilever under a tip load. If no unloading is assumed, a more analytical treatment is possible, as shown in the second part of the present paper. The model predicts that the ring always remains in full contact with the platens, in agreement with recent experiments by Avalle and Goglio on annealed aluminum tubes. Pull-away from the platens also observed in experiments is ascribed to end effects which cannot be modeled by a one-dimensional beam theory. However, it is argued that, even if there is pull-away, the effect on the overall force-deflection relation must be small because in both cases the forces exerted by the platens are concentrated at the ends of the contact region. Moving pictures of successive stages of deformation of the ring showing the formation of plastic loading and unloading zones in all three scenarios may be found on the web site www.people.virginia.edu/∼jgs/ring.html.