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Thin‐film field‐effect transistors showing n‐ and p‐type conduction under different bias conditions are produced from solution‐processable ambipolar blends of thieno[2,3‐b]thiophene terthiophene polymer and phenyl C61 butyric acid methyl ester (see Figure). Balanced charge transport in this blend is achieved by treating the insulator interface with alkyl‐chain silanes. Complementary‐like inverters have been fabricated on a single substrate, showing a maximum gain of 65.

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Mammary hamartomas were reported in 0.7% of all benign tumors of the female breast. Histologically breast hamartomas contain lobular breast tissue with various degrees of fibrous, fibrocystic, and adipose tissue. Rare types include muscular (myoid) and cartilage (chondroid) hamartomas. We report a case of muscular hamartoma in a man. A 36year-old man was admitted to the psychiatric unit with the diagnosis of schizophrenia. The patient complained of a slowly growing mass in his left breast. He denied any discharge from the nipple, but he complained of itching. A 2 cm ϫ 3 cm nontender mass was palpable. There was no evidence of axillary lymphadenopathy. A needle aspiration was nondiagnostic. The excisional biopsy specimen revealed fatty tissue which was edematous and hemorrhagic. Microscopically it showed multiple bundles of muscles organized randomly. Myoid hamartoma was the diagnosis. Mammary hamartoma is considered a female tumor exclusively. Myoid hamartoma has been reported previously in 25 women. We report a myoid hamartoma in a man and, to our knowledge, it is the first and only such case to be reported.

We have studied the effectiveness of beta heating on driving a deuterium–tritium (DT) ice layer toward uniformity within spherical inertial fusion targets. Beta heating results from the deposition of energy from the beta particles from the tritium decay in these targets. These targets are enclosed in a constant temperature environment. This study first considered a one-dimensional heat transfer model of an idealized target, geometry, and environment. We concluded that beta energy deposition can drive a nonuniform DT ice layer towards uniformity. The maximum rate at which this redistribution can occur is given by dδ/dt=δ̇=−δ/θTC, where δ=DT ice thickness in excess of that for a uniform layer and θTC=a time constant ≊1500 s. This translates to a factor of 10 reduction in nonuniformity every hour. We also evaluated, and continue to do so, the consequences of deviations from the idealized case assumptions and the selection of certain experimental parameters, on the actual behavior of DT ice in such cryogenic targets. The status of this work is such that we have confidence in the use of beta heating to drive the DT ice toward uniformity for reactor-size targets (∼1 mm and larger in diameter).

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Current collapse in AlGaN/GaN high electron mobility transistors was investigated using time-resolved Raman thermography. The virtual-gate mechanism was visualized by changes in the device temperature distribution, illustrating an effective gate lengthening up to 0.6 um. Two devices with different levels of current collapse are compared, demonstrating that the effective gate length increases for greater current collapse. A comparison of two-dimensional drift diffusion simulations with experimental data was used to estimate a lower limit for the charge trapping density in the virtual-gate region. This was found to be of the order of 2×1013 cm−2 for a device exhibiting relatively little current collapse.