Effect of Rainfall and Temperature on Perithecium Production of Botryosphaeria dothidea on Cankered Apple Branches.

Botryosphaeria dothidea is a fungal pathogen causing canker, dieback, and fruit rot of apple trees worldwide. Ascospores are an important source of inoculum of Botryosphaeria canker in China. Experiments were conducted under both controlled and natural conditions to study perithecium formation in relation to environmental conditions. Perithecia of B. dothidea were detected on cankered lesions throughout the apple growing season except in July and in some years including August under natural conditions. On newly formed canker lesions, the first perithecium was detected as early as August, about 1 week after rainfall. Perithecia matured successively, lasting from early August to June of the next year, with a peak in late September or early October. Temperature and rainfall are two key environmental factors affecting perithecium formation. Under controlled conditions, perithecia were produced only on cankered shoots incubated at test temperatures of 20 and 25°C and wetted by >3 days of simulated rainfall per week. The number of perithecia produced on canker lesions increased with the increase in rainfall duration. Perithecia were formed on canker shoots exposed to rainfall only in June, July, and August but not in September. Rainfall of >3 days per week can be used to predict the initial formation of perithecia in the main apple production areas in China to assist disease management.

Universality of flux-fluctuation law in complex dynamical systems.

Recent work has revealed a law governing flux fluctuation and the average flux in complex dynamical systems. We establish the universality of this flux-fluctuation law through the following steps: (i) We derive the law in a more general setting, showing that it depends on a single parameter characterizing the external driving; (ii) we conduct extensive numerical computations using distinct external driving, different network topologies, and multiple traffic routing strategies; and (iii) we analyze data from an actual vehicle traffic system in a major city in China to lend more credence to the universality of the flux-fluctuation law. Additional factors considered include flux fluctuation on links, window size effect, and hidden topological structures such as nodal degree correlation. Besides its fundamental importance in complex systems, the flux-fluctuation law can be used to infer certain intrinsic property of the system for potential applications such as control of complex systems for improved performance.

Enhanced photoluminescence of morin-bovine serum albumin on porous anodized aluminum oxide.

In this paper, the photoluminescence (PL) of porous anodized aluminum oxide (AAO) impregnated with essentially nonfluorescent morin and morin-bovine serum albumin (BSA) was investigated for the first time, respectively. The evident PL bands similar to that of morin-Al3+ complex in solution were observed and the intensity of the latter with morin-BSA was much greater than that of the former with only morin. Moreover, the enhancement increased with the larger pore diameter of the AAO membranes. The appearance of PL bands might be ascribed to the formation of morin-Al complexes in the AAO pores with its inner wall involved. A likely orderly luminescent model was proposed to be responsible for the observed enhancing phenomena of PL due to the coexistence of morin and BSA in the AAO pores.