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In this paper, we consider a class of polynomial mappings on Rmor Cmwhich is defined by the assumption that the delay equations induced by the mappings have leading monomials in a single variable. We show that for any mapping from this class, the nonwandering set is bounded while for all unbounded orbits, some kind of monotonicity takes place. The class under consideration is proved to contain, in particular, the generalized Hénon mappings and the Arneodo–Coullet–Tresser mappings.

Abstract: By the method of the optical spectrsocopy of diffuse reflection in the region 0.5–5.0 eV, accelerated aging of pigment compositions with synthetic materials used in restoration of paint layers of paintings is investigated. Composition containing pigments zinc and titanium oxides (white pigments), chromium oxide and copper carbonate (green pigments), and iron oxide (brown pigment) and reinforcing materials vinyl acetate-ethylene copolymer, fluorolon F-42L, and polyvinyl alcohol are investigated. It is established that the appearance of color in pigment impregnation and subsequent heating is observed only in the compositions of reinforcing materials with white pigments and occurs as a result of heterogeneous reactions that lead to the formation in the pigment of color centers bonded by oxygen vacancies.

Morphine-6-glucuronide (M-6-G) is an active metabolite that may contribute to the clinical effects produced by systemic administration of morphine. To help clarify the extent to which M-6-G may cross the blood-brain barrier and exert effects, we employed high-performance liquid chromatography with electrochemical detection to measure the concentrations of M-6-G and morphine in the plasma and either ventricular (three patients) or lumbar (eight patients) CSF of cancer patients receiving chronic morphine therapy. The mean ratio of morphine in ventricular CSF: morphine in plasma was 0.71; the same ratio for M-6-G was only 0.077. The average molar ratio of M-6-G: morphine in ventricular CSF was 0.207, and the average molar ratio in plasma was 1.89. Although sampling problems render the lumbar CSF results less reliable, they were very similar. Thus, plasma contained approximately twice as much M-6-G as morphine, whereas CSF contained only one-fifth to one- third as much. These data confirm that M-6-G in plasma is distributed into CSF, but to a far lesser extent than morphine. They help explain animal data demonstrating much higher potency of M-6-G on administration into CSF than systemic administration and indicate that the degree to which M-6-G contributes to morphine effects in humans remains an unresolved question.

A modification to the f-Chart method has been developed to predict monthly and annual performance of thermosyphon solar domestic hot water systems. Stratification in the storage tank is accounted for through use of a modified collector loss coefficient. The varying flow rate throughout the day and year in a thermosyphon system is accounted for through use of a fixed monthly “equivalent average” flow rate. The “equivalent average” flow rate is that which balances the thermosyphon buoyancy driving force with the frictional losses in the flow circuit on a monthly average basis. Comparison between the annual solar fraction predited by the modified design method and TRNSYS simulations for a wide range of thermosyphon systems shows an RMS error of 2.6 percent.

The hypothesis that intracranial energy deposition from handheld cellular telephones causes acoustic neuroma was tested in an epidemiologic study of 90 patients and 86 control subjects. The relative risk was 0.9 (p0.07) and did not vary significantly by the frequency, duration, and lifetime hours of use. In patients who used cellular telephones, the tumor occurred more often on the contralateral than ipsilateral side of the head. Further efforts should focus on potentially longer induction periods.

ARTHUR MEYER firmly believed that the layering of starch granules corresponded to the alternation of day and night, and this belief is still shared by the authors of modern text-books. If this were true, then layers should disappear when starch granules develop under constant outer conditions of illumination, temperature and moisture. The only positive result of such an experiment was reported by van de Sande-Bakhuyzen for wheat. All other results appear to be negative. Salter found layers when starch granules grew in darkness, Fischer observed them after constant illumination, and according to Küster more than two layers could be deposited during one day.