functions as a precursor of vitamin A in mammals (G. A. J. Pitt, in I. Osler, H. Gutmonn, and U. Solms, ed., Carotenoids-1971Carotenoids- , 1971). The enzymes and genes which mediate the biosynthesis of cyclic carotenoids such as 13-carotene are virtually unknown. We have elucidated for the first time the pathway for biosynthesis of these carotenoids at the level of enzyme-catalyzed reactions, using bacterial carotenoid biosynthesis genes. These genes were cloned from a phytopathogenic bacterium, Erwinia uredevora 20D3 (ATCC 19321)
AbstractsObjective-For the treatment of elderly patients with asymptomatic meningiomas, it is important to determine their natural history. Based on results of follow up examinations, the natural history of such patients was clarified and prognostic factors concerning the potential of tumour growth in the aged were identified. Methods-The clinical records and imaging studies of 40 elderly (over 70 years) patients with asymptomatic meningiomas were analysed. The patients were followed up with repeated imaging studies, and changes in tumour size, clinical signs, and outcomes were evaluated. Results-There were 32 women and eight men with a mean age of 76.1 years. The mean follow up period was 38.4 months, ranging from 6 to 97 months. Six patients died during the follow up period from disorders other than the tumours, and one patient died as a result of the tumour. Twenty six patients (mean follow up period 41.8 months, range 10-97 months) showed no tumour growth. Fourteen patients showed tumour growth (mean follow up period 32.1 months, range 6-88 months). Five (four men and one woman) of these patients became symptomatic. Based on imaging analysis (1) calcification of the tumour was associated with no tumour growth (p=0.036), and (2) the tumour size at the initial diagnosis was related to subsequent tumour growth (p=0.016). Other possible factors related to tumour growth included sex and hyperintensity on MRI T2 weighted images. Conclusion-In elderly patients with asymptomatic meningiomas, careful clinical follow up with imaging studies is important. The imaging features mentioned may contribute to prediction of tumour growth. (J Neurol Neurosurg Psychiatry 2000;68:25-28)
The computerized scheme has the potential to improve the diagnostic accuracy of radiologists in the distinction of benign and malignant solitary pulmonary nodules.
CoO is a promising hole-extracting layer (HEL) for inverted planar perovskite solar cells with device configuration ITO/CoO/CHNHPbI/PCBM/Ag. The devices fabricated according to a simple solution procedure showed the best photovoltaic performance attaining power conversion efficiency (PCE) of 14.5% under AM 1.5 G 1 sun irradiation, which is significantly superior to those of materials fabricated with a traditional HEL such as PEDOT:PSS (12.2%), NiO (10.2%), and CuO (9.4%) under the same experimental conditions. We characterized the chemical compositions with XPS, crystal structures with XRD, and film morphology with SEM/AFM techniques. Photoluminescence (PL) spectra and the corresponding PL decays for perovskite deposited on varied HEL films were recorded to obtain the hole-extracting characteristics, for which the hole-extracting times show the order CoO (2.8 ns) < PEDOT:PSS (17.5 ns) < NiO (22.8 ns) < CuO (208.5 ns), consistent with the trend of their photovoltaic performances. The reproducibility and enduring stability of those devices were examined to show the outstanding long-term stability of the devices made of metal oxide HEL, for which the CoO device retained PCE ≈ 12% for over 1000 h.
A novel class of bit-flipping (BF) algorithms for decoding low-density parity-check (LDPC) codes is presented. The proposed algorithms, which are called gradient descent bit flipping (GDBF) algorithms, can be regarded as simplified gradient descent algorithms. Based on gradient descent formulation, the proposed algorithms are naturally derived from a simple non-linear objective function. †: Nagoya Institute of Technology, † †: Meijo University.
Our computerized scheme using the artificial neural network can improve the diagnostic accuracy of radiologists who are differentiating benign from malignant pulmonary nodules on high-resolution CT.
Non-enzymatic proteins including antibodies function as biomarkers and are used as biopharmaceuticals in several diseases. Protein-responsive soft materials capable of the controlled release of drugs and proteins have potential for use in next-generation diagnosis and therapies. Here, we describe a supramolecular/agarose hydrogel composite that can release a protein in response to a non-enzymatic protein. A non-enzymatic protein-responsive system is developed by hybridization of an enzyme-sensitive supramolecular hydrogel with a protein-triggered enzyme activation set. In situ imaging shows that the supramolecular/ agarose hydrogel composite consists of orthogonal domains of supramolecular fibers and agarose, which play distinct roles in protein entrapment and mechanical stiffness, respectively. Integrating the enzyme activation set with the composite allows for controlled release of the embedded RNase in response to an antibody. Such composite hydrogels would be promising as a matrix embedded in a body, which can autonomously release biopharmaceuticals by sensing biomarker proteins.
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