Application of minimum error entropy unscented Kalman filter in table tennis trajectory prediction.

Table tennis is important and challenging project for robotics research, and table tennis robotics receives a lot of attention from academics. Trajectory tracking and prediction of table tennis is an important technology for table tennis robots, and its estimation accuracy is also disturbed by non-Gaussian noise. In this paper, a novel Kalman filter, called minimum error entropy unscented Kalman filter (MEEUKF), is employed to estimate the motion trajectory of physical model of a table tennis. The simulation results show that the MEEUKF algorithm shows outstanding performance in tracking and predicting the trajectory of table tennis compared to some existing algorithms.

Phycobiliprotein as fluorescent probe and photosensitizer: A systematic review.

Phycobiliprotein is a natural product with many biological activities in various seaweeds. Phycobiliproteins have been widely used for anti-oxidation, anti-tumor, anti-inflammatory and immune-enhancing activities as a functional factor. Phycobiliproteins with high purity are considerably more expensive than common. To provide with a systematic, deep and detailed information about those features of phycobiliproteins, we performed a relatively comprehensive analysis on structural composition, the application of phycobiliproteins in the fields of fluorescent probe and photodynamic therapy in this report.

RNA-seq between asexual archeospores and meiosis-related conchospores in Neopyropia yezoensis using Smart-seq2.

In the life cycle of Neopyropia yezoensis, a potential model system for marine macroalgae, both asexual archeospores and meiosis-related conchospores develop into thalli (gametophyte). To understand this special life phenomenon in macroalgae, we picked out the two kinds of spores (10-30 cells in each sample) and conducted RNA-seq using Smart-seq2. Comparative analysis showed that light capture and carbon fixation associated differentially expressed genes (DEGs) were upregulated in archeospores, thus indicating that archeospores are in a state of rapid vegetative growth. In conchospores, protein synthesis and degradation, especially molecular chaperone, associated DEGs were up-regulated, indicating that complex life activities might be occurring in conchospores. There were 68 genes related to DNA replication and repair expressed in conchospores, showing that active DNA replication might occur in conchospores. Moreover, we found that one conchospore specifically expressed DEG (py04595: DNA helicase) only in diploid stages (conchocelis, sporangial filament) and three archeospores specifically expressed DEGs only in haploid stages (thalli). These molecular level results indicated that conchospores were closer to diploid, and might be the meiotic mother cells of N. yezoensis. In addition, we found that the knotted-like homeobox gene (PyKNOX), which might relate to the transition of gametophyte from sporophyte, was only expressed in sporophyte generation but not expressed in conchospores, archeospores and thalli, indicating the morphogenesis of gametophyte sin N. yezoensis might require the inactivation of PyKNOX.

Synthesis of Abscisic Acid in Neopyropia yezoensis and Its Regulation of Antioxidase Genes Expressions Under Hypersaline Stress.

Abscisic acid (ABA) is regarded as crucial for plant adaptation to water-limited conditions and it functions evolutionarily conserved. Thus, insights into the synthesis of ABA and its regulation on downstream stress-responsive genes in Neopyropia yezoensis, a typical Archaeplastida distributed in intertidal zone, will improve the knowledge about how ABA signaling evolved in plants. Here, the variations in ABA contents, antioxidant enzyme activities and expression of the target genes were determined under the presence of exogenous ABA and two specific inhibitors of the ABA precursor synthesis. ABA content was down-regulated under the treatments of each or the combination of the two inhibitors. Antioxidant enzyme activities like SOD, CAT and APX were decreased slightly with inhibitors, but up-regulated when the addition of exogenous ABA. The quantitative assays using real-time PCR (qRT-PCR) results were consistent with the enzyme activities. All the results suggested that ABA can also alleviate oxidative stress in N. yezoensis as it in terrestrial plant. Combined with the transcriptome assay, it was hypothesized that ABA is synthesized in N. yezoensis via a pathway that is similar to the carotenoid pathway in higher plants, and both the MVA and that the MEP pathways for isoprenyl pyrophosphate (IPP) synthesis likely exist simultaneously. The ABA signaling pathway in N. yezoensis was also analyzed from an evolutionary standpoint and it was illustrated that the emergence of the ABA signaling pathway in this alga is an ancestral one. In addition, the presence of the ABRE motif in the promoter region of antioxidase genes suggested that the antioxidase system is regulated by the ABA signaling pathway.

Regulation of Ferredoxin-NADP+ Oxidoreductase to Cyclic Electron Transport in High Salinity Stressed Pyropia yezoensis.

Pyropia yezoensis can survive the severe water loss that occurs during low tide, making it an ideal species to investigate the acclimation mechanism of intertidal seaweed to special extreme environments. In this study, we determined the effects of high salinity on photosynthesis using increasing salinity around algal tissues. Both electron transport rates, ETR (I) and ETR (II), showed continuous decreases as the salinity increased. However, the difference between these factors remained relatively stable, similar to the control. Inhibitor experiments illustrated that there were at least three different cyclic electron transport pathways. Under conditions of severe salinity, NAD(P)H could be exploited as an endogenous electron donor to reduce the plastoquinone pool in Py. yezoensis. Based on these findings, we next examined how these different cyclic electron transport (CETs) pathways were coordinated by cloning the gene (HM370553) for ferredoxin-NADP+ oxidoreductase (FNR). A phylogenetic tree was constructed, and the evolutionary relationships among different FNRs were evaluated. The results indicated that the Py. yezoensis FNR showed a closer relationship with cyanobacterial FNR. The results of both real-time polymerase chain reaction and western blotting showed that the enzyme was upregulated under 90-120‰ salinity. Due to the structure-function correlations in organism, Py. yezoensis FNR was proposed to be involved in NAD(P)H-dependent Fd+ reduction under severe salinity conditions. Thus, through the connection between different donors bridged by FNR, electrons were channeled toward distinct routes according to the different metabolic demands. This was expected to make the electron transfer in the chloroplasts become more flexible and to contribute greatly to acclimation of Py. yezoensis to the extreme variable environments in the intertidal zone.

Photorespiration participates in the assimilation of acetate in Chlorella sorokiniana under high light.

The development of microalgae on an industrial scale largely depends on the economic feasibility of mass production. High light induces productive suspensions during cultivation in a tubular photobioreactor. Herein, we report that high light, which inhibited the growth of Chlorella sorokiniana under autotrophic conditions, enhanced the growth of this alga in the presence of acetate. We compared pigments, proteomics and the metabolic flux ratio in C. sorokiniana cultivated under high light (HL) and under low light (LL) in the presence of acetate. Our results showed that high light induced the synthesis of xanthophyll and suppressed the synthesis of chlorophylls. Acetate in the medium was exhausted much more rapidly in HL than in LL. The data obtained from LC-MS/MS indicated that high light enhanced photorespiration, the Calvin cycle and the glyoxylate cycle of mixotrophic C. sorokiniana. The results of metabolic flux ratio analysis showed that the majority of the assimilated carbon derived from supplemented acetate, and photorespiratory glyoxylate could enter the glyoxylate cycle. Based on these data, we conclude that photorespiration provides glyoxylate to speed up the glyoxylate cycle, and releases acetate-derived CO2 for the Calvin cycle. Thus, photorespiration connects the glyoxylate cycle and the Calvin cycle, and participates in the assimilation of supplemented acetate in C. sorokiniana under high light.

Silicon enhances the growth of Phaeodactylum tricornutum Bohlin under green light and low temperature.

Phaeodactylum tricornutum Bohlin is an ideal model diatom; its complete genome is known, and it is an important economic microalgae. Although silicon is not required in laboratory and factory culture of this species, previous studies have shown that silicon starvation can lead to differential expression of miRNAs. The role that silicon plays in P. tricornutum growth in nature is poorly understood. In this study, we compared the growth rate of silicon starved P. tricornutum with that of normal cultured cells under different culture conditions. Pigment analysis, photosynthesis measurement, lipid analysis, and proteomic analysis showed that silicon plays an important role in P. tricornutum growth and that its presence allows the organism to grow well under green light and low temperature.

The physiological links of the increased photosystem II activity in moderately desiccated Porphyra haitanensis (Bangiales, Rhodophyta) to the cyclic electron flow during desiccation and re-hydration.

Photosynthetic electron flow changed considerably during desiccation and re-hydration of the intertidal macroalgae Porphyra haitanensis. Activities of both photosystem (PSI) and photosystem (PSII) increased significantly at moderate desiccation levels. Whereas PSII activity was abolished at an absolute water content (AWC) <24 %, PSI remained active with progressive decreases in AWC to values as low as 16 %. This result suggested that cyclic electron flow around PSI was still active after inactivation of linear electron flow following severe desiccation. Moreover, the PSI activity was restored more rapidly than that of PSII upon re-hydration. Pretreatment of the blades with 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) suppressed PSII activity following desiccation to an AWC of ~16 % AWC. Cyclic electron flow around PSI decreased markedly in blades pretreated with DCMU than in blades without pretreatment of DCMU during re-hydration in seawater containing DCMU. All results suggested that the activity of PSII under desiccation conditions plays an important role in the operation of cyclic electron flow during desiccation and its recovery during re-hydration. Therefore, we proposed the PSII activity during desiccation could eventually lead to the accumulation of NADPH, which could serve as electron donor for P700(+) and promote its recovery during re-hydration, thereby favoring the operation of cyclic electron flow.

Variation of expression levels of seven housekeeping genes at different life-history stages in Porphyra yezoensis.

In order to identify the optimal internal control for relative real-time PCR when studying target gene expression in the red alga Porphyra yezoensis, we quantified the expression of seven housekeeping genes (18S ribosomal RNA, 30S ribosomal protein S8, Polyubiquitin-2, Glyceraldehyde-3-phosphate dehydrogenase, Elongation factor 1-alpha, Beta-tubulin and Actin 3) at different life-history stages. Absolute quantification was done by normalization to total RNA quantity and by normalization to genomic DNA quantity. We used these two normalization approaches, comparing the differences of expression levels of all candidate housekeeping genes between any two generations and across three life-history stages (filamentous sporophytes, leafy gametophytes and conchospores). We found GAPDH had the best stability in all cases and we recommend that GAPDH be considered as a potential internal control for gene expression studies at different life-history stages in P. yezoensis.

Genetic similarity analysis within Pyropia yezoensis blades developed from both conchospores and blade archeospores using AFLP(1).

Pyropia yezoensis (Ueda) M. S. Hwang et H. G. Choi (previously called Porphyra yezoensis) is an economically important alga. The blades generated from conchospores are genetic chimeras, which are not suitable for genetic similarity analysis. In this study, two types of blades from a single filament of P. yezoensis sporophyte filament were obtained. One type, ConB, consisted of 40 blades that had germinated from conchospores. The other type, ArcB, consisted of 88 blades that had germinated from archeospores released from ConB. Both of them were analyzed by amplified fragment length polymorphism. The low genetic similarity levels for both conchospore-germinated and archeospore-germinated blades demonstrated that the conchcelis we used was cross-fertilized. Furthermore, a higher polymorphic loci ratio (98.6%) was detected in ArcB than in ConB (80.7%), and the average genetic similarity of ArcB (average 0.61) was lower than that of ConB (average 0.71). These differences indicated that genetic analysis using ArcB gives more accurate results.

AFLP and SCAR markers associated with the sex in Gracilaria lemaneiformis (Rhodophyta).

Gracilaria lemaneiformis (Bory de Saint-Vincent) Greville, an important marine alga, has great economic and nutritional value. However, during the nonreproductive period, it is difficult to distinguish the sporophyte, male gametophyte, and female gametophyte from each other by appearance. Amplified fragment length polymorphism (AFLP) is a multilocus marker technique, which was used in this study to identify markers associated with G. lemaneiformis sex type. By applying 80 primer combinations in the screening process, three fragments were found that were specific to male or female forms of the alga. A 173 bp band and an 89 bp band were found in the sporophyte and the male gametophyte by using primer E-AGG/M-CGT. E-ACC/M-CGG was used to amplify a 118 bp specific fragment in the sporophyte and the female gametophyte. Sequence characterized amplified region (SCAR) primers were designed and showed the expected bands at the corresponding stages. This suggested that the SCAR markers that had been developed were successful. The joint use of the three primer pairs allowed us to characterize sex and the G. lemaneiformis developmental phase in the nondescript stages. Rapid gender testing is expected to improve cross-breeding experiments and other genetic research in this economically important seaweed.

Cyclophilin Participates in Responding to Stress Situations in Porphyra haitanensis (Bangiales, Rhodophyta).

Porphyra haitanensis (T. J. Chang & B. F. Zheng) is an important economic alga found off the southern coast of China. It has evolved a strong tolerance against stress, which is an important survival characteristic. Cyclophilin has been shown to be involved in the stress response of plants and algae. To investigate the tolerance against stress in Porphyra, we isolated the cyclophilin PhCYP18 gene (Accession number JQ413239) and measured its expression over different generations and stress conditions. In P. haitanensis, cyclophilin PhCYP18 accumulated more in the filamentous sporophyte generation than in the blade gametophyte generation. This difference was thought to be due to harsh environments and a gene dosage effect. It has been found, however, that PhCYP18 expression was dysregulated in blades under high salt stress, strong irradiance stress and multifactorial stress compared to blades under normal conditions. Moreover, the changes were not linearly related to the degree of stress. It was therefore thought that PhCYP18 actively responded to stress situations and induced strong stress tolerance, which is evident in P. haitanensis.

[Clinical application of tubal reconstruction after laparoscopic tubal pregnancy operation].

OBJECTIVE: To investigate the effectiveness of the tubal reconstruction after laparoscopic tubal pregnancy operation by comparing with simple laparoscopic tubal pregnancy operation. METHODS: Between May 2007 and May 2010, 63 patients with tubal pregnancy underwent laparoscopic tubal pregnancy operation and tubal reconstruction in 30 cases (trial group) or simple laparoscopic tubal pregnancy operation in 33 cases (control group). There was no significant difference in age, pregnancy time, and position between 2 groups (P > 0.05). The tube patency test and hysterosalpingography (HSG) were carried out to evaluate the efficacy. RESULTS: The operation was successfully completed in 29 cases of trial group; 1 case had too severe adhesion to receive re-anastomosis and was excluded. The tube patency test showed that the tube was patency in 26 cases of trial group and in 2 cases of control group during operation, showing significant difference (Z = 5.86, P = 0.00); it was patency in 25 cases of trial group and in 26 cases of control group at 1 month after operation, showing no significant difference (Z = 0.48, P = 0.63). HSG examination showed tube was patency in 25 cases of trial group and in 2 cases of control group at 2 months after operation, showing significant difference (Z = 5.35, P = 0.00). After 24 months, intrauterine pregnancy of trial group (n = 25, 86.20%) was significantly higher than that of control group (n = 19, 57.58%) (chi2 = 7.72, P = 0.01). CONCLUSION: The reconstruction after laparoscopic tubal pregnancy operation can significantly increase the intrauterine pregnancy rate, and it is better than simple laparoscopic tubal pregnancy operation.

Comparative Analysis of MicroRNAs between Sporophyte and Gametophyte of Porphyra yezoensis.

Porphyra yezoensis Ueda is an intertidal marine red algae that has received increasing attention as a model organism owing to its important role in biological research and the agronomic industry. The two generations of Porphyra yezoensis, the sporophyte and the gametophyte, have the same genome but show great differences in many aspects, including structural features, habitat, and gene expression. To identify miRNAs and their probable roles in P. yezoensis development, we constructed and sequenced libraries of small RNA from P. yezoensis sporophytes and gametophytes. The sequencing data were analyzed, and 14 miRNAs were identified, with only one common to these two samples. Our results show that P. yezoensis has a complex small RNA processing system containing novel miRNAs that have no identifiable homolog in other organisms. These miRNAs might have important regulatory roles in development of the different generations of P. yezoensis.

SELECTION OF INTERNAL CONTROL GENE FOR EXPRESSION STUDIES IN PORPHYRA HAITANENSIS (RHODOPHYTA) AT DIFFERENT LIFE-HISTORY STAGES(1).

Accurate gene quantification depends on the use of an appropriate internal control gene, which should be verified before its use for normalizing data. Housekeeping genes, which are expressed at relatively constant levels, are generally regarded as candidate internal control genes. To determine the ideal internal control for gene expression profiles for Porphyra haitanensis T. J. Chang et B. F. Zheng (Bangiales, Rhodophyta) at different life-history stages, we used absolute quantification to assess the expression levels of six housekeeping genes (18S ribosomal RNA, 30S ribosomal protein, glyceraldehyde-3-phosphate dehydrogenase, elongation factor 3, alpha-tubulin, and beta-tubulin) at the sporophyte and gametophyte stages. Housekeeping genes were selected by comparing the differences of observed copy numbers in sporophytes and in gametophytes. TubB (beta-tubulin) was found to be the optimal internal control gene, because it showed the smallest difference of gene expression. Compared with TubB, other housekeeping genes had greater variation of expression to different degrees.

PSI-driven cyclic electron flow allows intertidal macro-algae Ulva sp. (Chlorophyta) to survive in desiccated conditions.

Ulva sp. (Chlorophyta) is a representative species of the intertidal macro-algae responsible for the green tides that occurred along the shores of Qingdao in 2008 and had detrimental effects on the preparation for the 2008 Beijing Olympic Games sailing competition. In view of its significance, we have investigated the photosynthetic performance of the photosystems and the changes in photosynthetic electron transport that occur during desiccation and rehydration of Ulva sp. The PSII activity in Ulva sp. declined gradually during the course of desiccation, which was reflected by the decreased maximum quantum yield and effective quantum yield, whereas the PSI activity fluctuated significantly. In contrast, the electron transport rates of PSII approached zero at severe levels of desiccation, but the electron transport of PSI, which still operated, could be suppressed effectively by a specific inhibitor. Furthermore, the electron transport of PSI during rehydration of desiccated thalli was recovered faster than that of PSII. All these results implied that the linear electron flow was abolished in desiccated Ulva sp., whereas the cyclic PSI activity was significantly elevated, was still active at severe levels of desiccation and could be restored faster than PSII activity. Based on these results, we concluded the PSI-driven cyclic electron flow might provide desiccation tolerance and additional flexibility for the cell physiology of Ulva sp. under desiccation conditions, which might be one of the most important factors that make Ulva sp. well suited to experience daily cycles of desiccation at low tide and rehydration at high tide.

An economic assessment of astaxanthin production by large scale cultivation of Haematococcus pluvialis.

Although natural sources have long been exploited for astaxanthin production, it is still uncertain if natural astaxanthin can be produced at lower cost than that of synthetic astaxanthin or not. In order to give a comprehensive cost analysis of astaxanthin production from Haematococcus, a pilot plant with two large scale outdoor photobioreactors and a raceway pond was established and operated for 2 years to develop processes for astaxanthin production from Haematococcus. The developed processes were scaled up to a hypothetical plant with a production capacity about 900 kg astaxanthin per year, and the process economics was preliminarily assessed. Based on the analysis, the production cost of astaxanthin and microalgae biomass can be as low as $718/kg and $18/kg respectively. The results are very encouraging because the estimated cost might be lower than that of chemically synthesized astaxanthin.

Differential expression of rubisco in sporophytes and gametophytes of some marine macroalgae.

Rubisco (ribulose-1, 5-bisphosphate carboxylase/oxygenase), a key enzyme of photosynthetic CO(2) fixation, is one of the most abundant proteins in both higher plants and algae. In this study, the differential expression of Rubisco in sporophytes and gametophytes of four seaweed species--Porphyra yezoensis, P. haitanensis, Bangia fuscopurpurea (Rhodophyte) and Laminaria japonica (Phaeophyceae)--was studied in terms of the levels of transcription, translation and enzyme activity. Results indicated that both the Rubisco content and the initial carboxylase activity were notably higher in algal gametophytes than in the sporophytes, which suggested that the Rubisco content and the initial carboxylase activity were related to the ploidy of the generations of the four algal species.

Comparison of chlorophyll and photosynthesis parameters of floating and attached Ulva prolifera.

In mid-May 2008 a serious green tide caused mainly by floating Ulva prolifera (Müller) J. Agardh (Chlorophyta, Ulvales) thalli struck the coastal area of Qingdao, China. To understand the present physiological conditions of the floating alga, in this work both laboratory and field investigations were conducted on the floating U. prolifera thalli in comparison with the attached U. prolifera thalli collected from the area. The floating thalli of three distinctively different colors and attached thalli at three different stages of sporangium formation process were characterized under a microscope, while their photosynthetic parameters were determined with chlorophyll fluorescence technology. On the other hand, the sporangium formation status of the floating U. prolifera thalli was surveyed both in the laboratory and in the field. Comparisons showed that both of the paired morphological characteristics and the paired physiological parameters of the floating and attached U. prolifera thalli were consistent. Furthermore, some spores were confirmed in the field and some motile particles were found within the floating thalli. These results suggest that the floating U. prolifera thalli with different colors could be at different stages of sporangium formation. However, our results also showed that the floating alga thalli have only a limited reproductive potential. This might limit the duration and the further geographic expansion of the green algal bloom.

Large-scale recovery of C-phycocyanin from Spirulina platensis using expanded bed adsorption chromatography.

C-phycocyanin was purified on a large scale by a combination of expanded bed adsorption, anion-exchange chromatography and hydroxyapatite chromatography from inferior Spirulina platensis that cannot be used for human consumption. First, phycobiliproteins were extracted by a simple, scaleable method and then were recovered by Phenyl-Sepharose chromatography in an expanded bed column. The purity (the A(620)/A(280) ratio) of C-phycocyanin isolated with STREAMLINE column was up to 2.87, and the yield was as high as 31 mg/g of dried S. platensis. After the first step, we used conventional anion-exchange chromatography for the purification steps, with a yield of 7.7 mg/g of dried S. platensis at a purity greater than 3.2 and with an A(620)/A(650) index higher than 5.0. The fractions from anion-exchange chromatography with a level of purity that did not conform to the above standard were subjected to hydroxyapatite chromatography, with a C-PC yield of 4.45 mg/g of dried S. platensis with a purity greater than 3.2. The protein from both purification methods showed one absolute absorption peak at 620 nm and a fluorescence maximum at 650 nm, which is consistent with the typical spectrum of C-phycocyanin. SDS-PAGE gave two bands corresponding to 21 and 18 kDa. In-gel digestion and LC-ESI-MS showed that the protein is C-phycocyanin.