Parasitic plants are defined as vascular plants that have developed specialized organs for the penetration of the tissues of other vascular plants (hosts) and the establishment of connections to the vascular strands of the host for the absorption of nutrients by the parasite. Parasitic plants are commonly divided into holoparasites that lack chlorophyll, do not carry out photosynthesis, and absorb organic matter from the hosts, and hemiparasites that are green, capable of photosynthesis, and absorb mainly inorganic nutrients from hosts. From ancient times, a number of parasitic plants have been widely used as traditional medicines in China. For the purpose of understanding the unusual secondary metabolism in parasitic plants and elucidating the pharmacologically active constituents of traditional Chinese medicines derived from parasitic plants, we initiated studies of the chemical constituents of Cynomorium songaricum RUPR. (Cynomoriaceae). C. songaricum belongs is an achlorophyllous holoparasite that is distributed in the northwestern part of China. Its stems are used as tonics and for the treatment of kidney disorders. 1)Among its chemical constituents, steroids, triterpenes, 2) fructosides, 3) flavanoids, and condensed tannins 4) have been reported previously. This paper deals with the structural elucidation of two new phenolic compounds (1 and 2) isolated from the stems of C. songaricum and their chemotaxonomic significance. Results and DiscussionMeOH extracts and 70% aqueous acetone extracts of the stems of C. songaricum were combined and subjected to partition between the EtOAc and H 2 O layers. The H 2 O layer and EtOAc layer were individually fractionated and purified by a combination of column chromatographies as described in the Experimental Methods section. Compounds 1 and 2, together with nicoloside, 5) gallic acid, phloridzin, 4) and rutin were isolated from the H 2 O layer. Methyl protocatechuicate, p-hydroxy benzoic acid, and (Ϫ) catechin were obtained from the EtOAc layer. The known compounds were identified by comparison with authentic samples or reported spectral and physical data.Compound , confirmed that 1 is a glucopyranoside of 1a. When downfield shifts of C-1 and C-4 of 1 were compared with those of 1a (Table 1), they indicated a glycosidic linkage at the C-4 hydroxyl group. The anomeric configuration of glucopyranose was determined to be b from the 3 J H1,H2 value (7 Hz). The absolute configuration of C-7Ј of 1 was further established to be R, since a positive Cotton effect at 291 nm 7) was observed in the CD spectrum. Thus compound 1 was determined to be (Ϫ)-isolariciresinol 4-O-b-D-glucopyranoside. Eight phenolic compounds including two new lignan glucopyranosides together with a known alkaloid were isolated from the stems of Cynomorium songaricum RUPR. (Cynomoriaceae). Their chemical structures were elucidated on the basis of spectral and chemical evidence. The chemotaxonomic significance of these metabolites is discussed.

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Radio Frequency Identification (RFID) is widely used to track and trace objects in traceability supply chains. However, massive uncertain data produced by RFID readers are not effective and efficient to be used in RFID application systems. Following the analysis of key features of RFID objects, this paper proposes a new framework for effectively and efficiently processing uncertain RFID data, and supporting a variety of queries for tracking and tracing RFID objects. We adjust different smoothing windows according to different rates of uncertain data, employ different strategies to process uncertain readings, and distinguish ghost, missing, and incomplete data according to their apparent positions. We propose a comprehensive data model which is suitable for different application scenarios. In addition, a path coding scheme is proposed to significantly compress massive data by aggregating the path sequence, the position, and the time intervals. The scheme is suitable for cyclic or long paths. Moreover, we further propose a processing algorithm for group and independent objects. Experimental evaluations show that our approach is effective and efficient in terms of the compression and traceability queries.

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