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Houttuynia cordata Thunb., called Yuxingcao in Chinese, is an important medicinal plant and vegetable consumed in the southern regions of China. This review aims to summarize studies on the phyto-physiological chemistry, cytology, molecular biology, and genomics of H. cordata. Studies on the physiology and biochemistry of H. cordata have grown over the past few decades. Phenotypic and agronomic traits, tissue culture, elemental analysis, photosynthetic studies, bioactive compound identification, and antioxidant research have been reported. Molecular biological studies, such as those of molecular markers, microRNAs, DNA variations, protein variations, and transcriptomes have also advanced. Recent studies have focused on the rDNA and chloroplast genome of this plant. This review could serve as a basis to perform the genetic breeding, genomic advance, and cultivation of this valuable diversified plant resource for medicinal applications and vegetable production. [ABSTRACT FROM AUTHOR]

Most topic detection methods mainly focus on the long text and news data set. There have some key characteristics in massive short texts, such as sparse, unstructured and much noise. Traditional topic detection methods are difficult to effectively find the topic. This paper presented a new method, which combined word co-occurrence with the weighted GN algorithm (CW-WGN for short). CW-WGN could be used to rapiily detect topic. This paper described the process of CW-WGN method in detail and specifically gave the implemented algorithms. Two datasets were collected from sina microblogging and main news website. It used the LDA and K-means methods as comparative methods and conducted comprehensive experiments. Experimental results show that CW-WGN can find more than 20% of the correct topics than K-means and LDA, and the purities of found topics are higher. In addition, the running time of CW-WGN is least, which means that CW-WGN can efficiently detect topic from actual massive short texts. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the effects of water stress on the photosynthetic characteristics, biomass accumulation, and principal medicinal compositions of Tribulus terrestri. Water stress changed the diurnal variation of T. terrestri photosynthesis, decreased the net photosynthetic rate and transpiration rate significantly, weakened the plant photosynthetic and assimilative capability, and accordingly, hindered the dry matter accumulation and decreased the biomass. However, water stress promoted the accumulation of gross saponins in T. terrestri. In the treatments with irrigation amounts 150 and 450 mm, the gross saponins content was 13.26 and 12.47 mg· g-1, respectively, being significantly different from that in the treatments with irrigation amounts 250 and 350 mm. The dynamic accumulation of gross flavonoids and gross saponins had an opposite tendency with that of biomass, namely, the contents of these principal medicinal compositions were the lowest when the biomass was the maximal. Correlation analysis showed that the biomass accumulation of T. terrestri was significantly correlated with outside environmental factors, while the contents of secondary metabolism products were affected not only by the outside environmental factors, but also by the inside factors such as biomass accumulation. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the effects of water stress on the photosynthetic characteristics, biomass accumulation, and principal medicinal compositions of Tribulus terrestri. Water stress changed the diurnal variation of T. terrestri photosynthesis, decreased the net photosynthetic rate and transpiration rate significantly, weakened the plant photosynthetic and assimilative capability, and accordingly, hindered the dry matter accumulation and decreased the biomass. However, water stress promoted the accumulation of gross saponins in T. terrestri. In the treatments with irrigation amounts 150 and 450 mm, the gross saponins content was 13.26 and 12.47 mg x g(-1), respectively, being significantly different from that in the treatments with irrigation amounts 250 and 350 mm. The dynamic accumulation of gross flavonoids and gross saponins had an opposite tendency with that of biomass, namely, the contents of these principal medicinal compositions were the lowest when the biomass was the maximal. Correlation analysis showed that the biomass accumulation of T. terrestri was significantly correlated with outside environmental factors, while the contents of secondary metabolism products were affected not only by the outside environmental factors, but also by the inside factors such as biomass accumulation.