Archaefructaceae is proposed as a new basal angiosperm family of herbaceous aquatic plants. This family consists of the fossils Archaefructus liaoningensis and A. sinensis sp. nov. Complete plants from roots to fertile shoots are known. Their age is a minimum of 124.6 million years from the Yixian Formation, Liaoning, China. They are a sister clade to all angiosperms when their characters are included in a combined three-gene molecular and morphological analysis. Their reproductive axes lack petals and sepals and bear stamens in pairs below conduplicate carpels.

The original English Morningness-Eveningness Questionnaire (MEQ) was translated into Chinese, and the circadian rhythmicity of 188 healthy Chinese subjects was tested using this version of the MEQ. We assessed the reliability and validity of the Chinese version and determined the cut-off points. In the Chinese version, 19 items were divided into two dimensions (i.e., sleep phase and time of greatest efficiency), and the cut-off points were determined to be the following: definitely evening type (14-46), moderately evening type (47-52), neither type (53-64), moderately morning type (65-69), and definitely morning type (70-86). Additionally, the Cronbach a coefficient was determined to be 0.769, which is satisfactory. The Chinese version of the MEQ has good psychometric properties, and its cut-off points can effectively differentiate between morningness and eveningness.

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Aluminum foams were fabricated by an infiltration process. The foams possess spherical cells with a fixed porosity of 65% and varied pore sizes which ranged from 1.3 to 1.9 mm. The spherical cells are interconnected by small pores or pore openings on the cell walls that cause the foams show a characteristic of open cell structures. The sound absorption coefficient of the aluminum foams was measured by a standing wave tube and calculated by a transfer function method. It is shown that the sound absorption coefficient increases with an increase in the number of pore openings in the unit area or with a decrease of the diameter of the pore openings in the range of 0.3 to 0.4 mm. If backed with an air cavity, the resonant absorption peaks in the sound absorption coefficient versus frequency curves will be shifted toward lower frequencies as the cavity depth is increased. The samples with the same pore opening size but different pore size show almost the same absorption behavior, especially in the low frequency range. The present results are in good agreement with some theoretical predictions based on the acoustic impedance measurements of metal foams with circular apertures and cylindrical cavities and the principle of electroacoustic analogy.