Nightly Home Hemodialysis: Fifteen Months of Experience in Lynchburg,Virginia

What constitutes adequate dialysis has been debated in the nephrology literature over the past eight years. The mortality rate of patients on dialysis in the United States is about 20% per year. We believed that short and infrequent dialysis sessions contributed to poor outcomes. To improve the results, Lynchburg Nephrology started the nightly home hemodialysis (NHHD) program in September 1997. Ten patients were trained in the first 15 months of the program. Patients dialyzed 7 – 9 hours, 6 nights/week, using the Fresenius 2008H machine. A standard dialysis solution with 2.0 mEq/L potassium, calcium concentration of 3.0 – 3.5 mEq/L was used. Dialysis solution flow rates were 200 – 300 mL/min. Serum phosphate levels were maintained above 2.5 mg/dL by adding 0 – 45 mL Fleet's Phosphosoda to the bicarbonate bath. Patients had marked improvement in quality of life as measured with the SF-36. Blood pressure was better controlled with fewer medications. All phosphate binders were eliminated. Caloric intake and protein intake increased to normal levels as measured by three-day dietary histories pre-NHHD, and at 3, 6, and 12 months on NHHD. Epoetin alfa dosages were reduced by about 50%. Nightly home hemodialysis should be considered as a valuable modality option for end-stage renal disease patients; it is potentially superior to conventional thrice-weekly hemodialysis.     

Artificial Agent Action in Markets

We summarise our experiences of a number of demonstrators and simulation experiments designed to test the feasibility of using artificial decision making agents in real-time domains, and comment on the significance of our results to autonomous artificial agent action patterns in markets. Our main hypothesis is that the use of norms can extend the capability of artificial decision makers beyond what is obtained from implementing individual utility maximizers in keeping with rational choice theory.     

Optical and Flame-Retardant Properties of a Series of Polyimides Containing Side Chained Bulky Phosphaphenanthrene Units

Among the multitude of polymers with carbon-based macromolecular architectures that easily ignite in certain applications where short circuits may occur, polyimide has evolved as a class of polymers with high thermal stability while exhibiting intrinsic flame retardancy at elevated temperatures via a char-forming mechanism. However, high amounts of aromatic rings in the macromolecular backbone are required for these results, which may affect other properties such as film-forming capacity or mechanical properties; thus, much work has been done to structurally derivatize or make hybrid polyimide systems. In this respect, flexible polyimide films (PI(1–4)) containing bulky 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) units have been developed starting from commercial dianhydrides and an aromatic diamine containing two side chain bulky DOPO groups. The chemical structure of PI(1–4)) was characterized by ¹H NMR, ¹³C NMR and ³¹P NMR spectroscopy. The optical properties, including absorption and luminescence spectra of these polymers, were analyzed. All polyimides containing DOPO derivatives emitted blue light with an emission maxima in the range of 340–445 nm, in solvents such as N,N-dimethylformamide, N-methyl-2-pyrrolidone, chloroform, and N,N-dimethylacetamide, while green light emission (λ_em = 487 nm for PI-4) was evidenced in a thin-film state. The thermal decomposition mechanism and flame-retardant behavior of the resulting materials were investigated by pyrolysis-gas-chromatography spectrometry (Py-GC), scanning electron microscopy (SEM), EDX maps and FTIR spectroscopy. The residues resulting from the TGA experiments were examined by SEM microscopy images and FTIR spectra to understand the pyrolysis mechanism.     

Digital Light-Processing (DLP) 3D Printing of Magnesium Phosphate Minerals and Cements

Digital light processing (DLP) enables the fabrication of complex 3D structures based on a photopolymerizable resin usually containing a photo initiator and an UV or photo absorber. The resin and thus the final properties of the printed structures can be adjusted by adding fillers like bioceramic powders relevant for bone-regeneration applications. Herein, a water-based and biocompatible poly(ethylene glycol diacrylate) (PEGDA) resin containing the photo initiator lithium-phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) enables the production of 3D structures via DLP. The addition of calcium magnesium phosphate cement (CMPC) powder, acting as photo absorber, leads to higher accuracy of the final structures. After curing the printed construct in a diammonium–hydrogen phosphate (DAHP) bath for hardening, the resulting mechanical properties can be adjusted without post-process sintering. Solid loading of up to 40 wt% CMPC powder is possible, and the resins are investigated regarding their rheological behavior and printability. The resulting constructs are analyzed in respect to their surface morphology using scanning electron microscope (SEM), porosity, phase composition using X-ray diffraction (XRD) methods, as well as mechanical properties influenced by the hardening process using DAHP for different durations.     

Surface/Thickness Translated: Design-Build as Vehicle

The Building-Design Workshop at the Taubman College of Architecture and Urban Planning pursues the integration of teaching, design research, and the design-build process. The program brings University-sponsored projects into the teaching context, offering a unique forum for testing pedagogies about making. Collaborating with faculty on both architectural and constructional aspects of a project, students are given a valuable occasion to realize a design in built form. The project shown here is a renovation of the College's Faculty Resource Room (FRR), a support facility for the research and teaching of the Architecture and Planning faculty.     

Actor networks and the construction of applicable knowledge: the case of the Timbre Brownfield Prioritization Tool

This article deals with experiences acquired during the process of developing the Timbre Brownfield Prioritization Tool (TBPT). Developing a decision support tool that takes into account the expectations and experiences of its potential users is similar to creating applicable knowledge by the joint action of scientists and heterogeneous actors. Actor network theory is used to explore the construction of this form of applicable knowledge as a process of actor network creation. Following the French sociologist Callon, networks are seen to be initiated and carried out by a group of scientists (tool developers) via four moments of translation, called problematization, interessement, enrolment and mobilization. Each step in the construction of the TBPT—from the initial research question to the final model—can be linked in retrospect to changing configurations of actor networks. Based on the experiences of the tool developers in the Czech Republic, Poland, Germany and Romania, we illustrate how these configurations varied across space and time. This contribution emphasizes the ability to correlate gains in knowledge with the more visible changes in the scope of actor networks in order to highlight achievements but also limitations in acquiring applicable knowledge.