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Here, we report on the dual functionality of tungsten oxide for application as an efficient electron and hole injection/transport layer in organic light-emitting diodes (OLEDs). We demonstrate hybrid polymer light-emitting diodes (Hy-PLEDs), based on a polyfluorene copolymer, by inserting a very thin layer of a partially reduced tungsten oxide, WO2.5, at the polymer/Al cathode interface to serve as an electron injection and transport layer. Significantly improved current densities, luminances, and luminous efficiencies were achieved, primarily as a result of improved electron injection at the interface with Al and transport to the lowest unoccupied molecular orbital (LUMO) of the polymer, with a corresponding lowering of the device driving voltage. Using a combination of optical absorption, ultraviolet spectoscopy, X-ray photoelectron spectroscopy, and photovoltaic open circuit voltage measurements, we demonstrate that partial reduction of the WO3 to WO2.5 results in the appearance of new gap states just below the conduction band edge in the previously forbidden gap. The new gap states are proposed to act as a reservoir of donor electrons for enhanced injection and transport to the polymer LUMO and decrease the effective cathode workfunction. Moreover, when a thin tungsten oxide film in its fully oxidized state (WO3) is inserted at the ITO anode/polymer interface, further improvement in device characteristics was achieved. Since both fully oxidized and partially reduced tungsten oxide layers can be deposited in the same chamber with well controlled morphology, this work paves the way for the facile fabrication of efficient and stable Hy-OLEDs with excellent reproducibility.

The one-bit memory-cell structure of choice for use in digital integrated circuit (IC) applications would be a single field-effect-transistor (FET) that includes a binary information storage element and acts as a memory-cell addressing switch. The storage element can be placed in two readily discernible physical states that modulate the transistor’s channel conductivity enabling data to be read electrically by sensing the current level of the transistor. The data sensing mode of memory transistors renders them robust against read-current distortions to the storage mechanism; an important advantage over their two-terminal counterparts. In the case of organic memory transistors, various combinations of storage elements, in the form of charged electrets or ferroelectric-like gate dielectrics, and organic semiconductor channels have been actively investigated for emerging large-area lowperformance logic circuit applications on flexible substrates. Regarding inorganic Si-based ICs, the polysilicon floating-gate (FG) storage element has been the dominant technology for the implementation of extremely durable nonvolatile memory transistors (currently referred to as FG flash transistors) for the past three decades. With the increasing challenge of scaling flash memory, various storage elements based on novel gate materials and physical storage principles have been proposed as modified flash cells. Significant development efforts have been devoted to storage elements exploiting: (a) the trapping of electrons and/or holes in nitride gate dielectrics or in isolated nanocrystals embedded in FET gate dielectrics (referred as nano-floating gate memory, NFGM); (b) the ferroelectric polarization of gate dielectrics (ferroelectric memory FET, FEMFET); and (c) the motion of protons within the gate dielectrics (proton memory). Apart from the benefits of using a modified flash memory architecture and of being radiation-tolerant, the proton memories also have the advantage, over FEMFETs and NFGMs, of being able to be programmed at much lower voltages, thus offering an attractive alternative for ultradense low-voltage, non-volatile data storage. While promising device results have been obtained, the conventional methods of forming protonmemories still face critical issues towards the development of commercial products. For example, all

We describe a patient in remission from acute lymphoblastic leukemia who developed a painless common peroneal neuropathy. Magnetic resonance imaging (MRI) revealed nerve thickening and enhancement, while a positron emission tomography (PET) scan demonstrated increased fluorodeoxyglucose uptake in a large segment of the neurovascular bundle, suggesting peripheral nerve infiltration. Both findings resolved following treatment with chemotherapy that crossed the blood-nerve barrier. In selected patients presenting with peripheral neuropathy, MRI and PET scan can be helpful in the diagnosis of peripheral nerve infiltration.

Meperidine and its principle metabolite, normeperidine, were given intravenously to four non-human primates prior to cesarean delivery in an equivalent dose for human parturients. The status of the infants regarding neonatal depression was assessed at delivery. Repeated blood samples from both the mother and the neonate were obtained over a period of 4 days. The levels of meperidine and normeperidine were analyzed. The results showed that the metabolism of meperidine and normeperidine in the non-human primate was essentially the same as that observed in the human parturient. In addition, normeperidine appeared to be more toxic than meperidine to the neonate. Finally, there does not appear to be an evidence for neonatal metabolism of meperidine to normeperidine.