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In molecular programming, the Chemical Reaction Network model is often used to describe real or hypothetical systems. Often, an interesting computational task can be done with a known hypothetical Chemical Reaction Network, but often such networks have no known physical implementation. One of the important breakthroughs in the field was that any Chemical Reaction Network can be physically implemented, approximately, using DNA strand displacement mechanisms. This allows us to treat the Chemical Reaction Network model as a programming language and the implementation schemes as its compiler. This also suggests that it would be useful to optimize the result of such a compilation, and in general to find effective ways to design better DNA strand displacement systems. We discuss DNA strand displacement systems in terms of "motifs", short sequences of elementary DNA strand displacement reactions. We argue that describing such motifs in terms of their inputs and outputs, then building larger systems out of the abstracted motifs, can be an efficient way of designing DNA strand displacement systems. We discuss four previously studied motifs in this abstracted way, and present a new motif based on cooperative 4-way strand exchange. We then show how Chemical Reaction Network implementations can be built out of abstracted motifs, discussing existing implementations as well as presenting two new implementations based on 4-way strand exchange, one of which uses the new cooperative motif. The new implementations both have two desirable properties not found in existing implementations, namely both use only at most 2-stranded DNA complexes for signal and fuel complexes and both are physically reversible. There are reasons to believe that those properties may make them more robust and energy-efficient, but at the expense of using more fuel complexes than existing implementation schemes.

Japanese traditional rice production technique features “sparse seeding, long cultivation, scattered planting and limited transplanting”, and scientific rice production methods of deep plowing, fertilization, weeding, irrigation and drainage are employed. This technique has reversed the common practice of “dense seeding and planting” in rice paddies and changed the history of growing rice spikes purely out of stems, thus enabling stable and high yields of several tillering grain crops including rice. The technique can provide a useful reference for developing modern rice production in warm areas.

Compared to conventional imaging spectrometry,computational imaging spectrometry has the advantages of high throughput snapshot imaging etc.But because of the presence of the dispersive element,computational imaging spectrometry suffers the effect of spectral line bending.To study the effect of spectral line bending on signal acquisition,spatial-spectral aliasing and reconstructed result in computational imaging spectrometry,combined with the principle of computational imaging spectrometry and reconstruction algorithm,the relative peak signal-to-noise ratio of the reconstructed image and the maximal error of the reconstructed spectral curve with different spectral offset were calculated and analyzed.The experimental result showed that spectral offset of the signal acquired by the detector will change the degree of spatialspectral aliasing.The reconstructed results with spectral line bending exhibit distinct errors compared with no spectral line bending.And both sides of the reconstructed spectral curve tend to smooth.In order to reconstruct the object scene with high accuracy,spectral offset should be no more than half a pixel for computational imaging spectrometry with 10nm resolution.

The rural commodity economy in the Edo period developed by leaps and bounds under the influence of institution, policy, technology and other factors. From the mid-17th century, the specific area of cash crops gradually took shape in Japan and the large-scale cultivation of cash crops greatly promoted the development of rural handicrafts, thereby creating the conditions for the initiation of the capitalist relations of production. The development of rural commodity economy not only changed the traditional mode of operation and production of Japanese farmers, but also accelerated the class differentiation, shook and disintegrated the economic foundation and class basis of Bakuhan society, and created the preconditions for the later Meiji Restoration.

Coded aperture snapshot spectral imaging (CASSI) has been discussed in recent years. It has the remarkable advantages of high optical throughput, snapshot imaging, etc. The entire spatial-spectral data-cube can be reconstructed with just a single two-dimensional (2D) compressive sensing measurement. On the other hand, for less spectrally sparse scenes, the insufficiency of sparse sampling and aliasing in spatial-spectral images reduce the accuracy of reconstructed three-dimensional (3D) spectral cube. To solve this problem, this paper extends the improved CASSI. A band-pass filter array is mounted on the coded mask, and then the first image plane is divided into some continuous spectral sub-band areas. The entire 3D spectral cube could be captured by the relative movement between the object and the instrument. The principle analysis and imaging simulation are presented. Compared with peak signal-to-noise ratio (PSNR) and the information entropy of the reconstructed images at different numbers of spectral sub-band areas, the reconstructed 3D spectral cube reveals an observable improvement in the reconstruction fidelity, with an increase in the number of the sub-bands and a simultaneous decrease in the number of spectral channels of each sub-band.