Real-time analysis of large-scale neuronal imaging enables closed-loop investigation of neural dynamics.

Large-scale imaging of neuronal activities is crucial for understanding brain functions. However, it is challenging to analyze large-scale imaging data in real time, preventing closed-loop investigation of neural circuitry. Here we develop a real-time analysis system with a field programmable gate array-graphics processing unit design for an up to 500-megabyte-per-second image stream. Adapted to whole-brain imaging of awake larval zebrafish, the system timely extracts activity from up to 100,000 neurons and enables closed-loop perturbations of neural dynamics.

[Genetic diversity and population structure of germplasm resources of Amomum villosum based on SSR markers].

Amomum villosum, serving as an important medicinal material, is complex in the genetic background of germplasm resources. Exploring the genetic diversity and genetic relationship of germplasm resources is conducive to clarifying the germplasm source and genetic background of A. villosum, so as to improve the efficiency of parent selection and variety breeding of A. villosum. Seventy-one pairs of SSR primers were used for PCR amplification of 84 A. villosum samples by polyacrylamide gel electrophoresis. Fifty-four pairs of SSR primers with high polymorphism were screened out for the analysis of genetic diversity. The results showed that 293 alleles were detected from 84 germplasm resources by 54 pairs of SSR primers, with an average of 5.32 alleles for each pair of primers, and a variation range of 3-8, and the primer AVL12 marked the highest number of alleles. The PIC value of each locus varied from 0.068 7 to 0.828 9, with an average of 0.529 9, and the highest was marked by AVL24. The genetic diversity of A. villosum was the highest in Yunnan, followed by Guangxi, and the lowest was found in Guangdong. The population structure analysis and cluster analysis showed that the samples were classified into two groups. In terms of origin, samples from Yunnan and Guangxi had a close genetic relationship, and there was no obvious differentiation of A, villosum resources from different origins. In this study, 54 pairs of SSR markers were used to analyze the genetic diversity and population structure of 84 germplasm resources, which can reflect the genetic relationship between A. villosum samples from different germplasm sources and different populations, thus providing a theoretical basis for the collection, research, and breeding of A. villosum resources.

Effects of Periodically Repeated Heat Events on Reproduction and Ovary Development of Agasicles hygrophila (Coleoptera: Chrysomelidae).

Insect development occurs within a specific temperature range. Constant temperature studies may produce misleading information on the eco-physiological impacts of temperature on the population dynamics of an insect species, as in most natural environments, temperature usually undergoes daily variation. In China, field surveys showed that the decline in the Agasicles hygrophila (Selman & Vogt) (Coleoptera: Chrysomelidae) population from early August to late September in summer resulted in difficulties in effectively controlling the population of Alternanthera philoxeroides (Mart.) Griseb (Amaranthaceae). Previous studies have largely ignored more natural, fluctuating conditions. In our study, we first investigated the impacts of different temperature conditions (25°C constant temperature for 20 h with a 4-h period of a high temperature of either 30°C, 33°C, 36°C, or 39°C) on adult reproduction and longevity, egg development time, egg hatch rate, female ovarian development, and oogenesis of A. hygrophila. Our results indicated that high temperatures of 30°C and 33°C did not affect the female ovarian development and oogenesis of A. hygrophila Contrarily, high temperatures of 36°C and 39°C negatively affected the population development of A. hygrophila. At 36°C and 39°C, the egg hatch rates were very low, and the egg development times significantly lengthened. The frequency of abnormal ovaries significantly rose at 39°C. We concluded that the decline in the A. hygrophila population during August and September may be related to the extreme high temperatures that frequently occur in summer. These results help provide a better understanding of A. hygrophila population dynamics under natural conditions.